Prefrontal cortex

Maintaining your myelin, Part 1

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Three papers on myelin and oligodendrocytes, starting with a 2023 review:

“Myelin is the spiral ensheathment of axons by a lipid and cholesterol-rich glial cell membrane that reduces capacitance and increases resistance of the axonal membrane. Axonal myelination speeds up nerve conduction velocity as a function of axon diameter.

While myelination proceeds rapidly after birth in the peripheral nervous system, central myelination is a spatially and temporally more regulated process. Ongoing myelination of the human brain has been documented at up to 40 years of age. This late myelination in the adult cortex is followed by exhaustion of oligodendrocyte precursor cells (OPC) with senescence and a gradual loss of myelin integrity in the aging brain.

The brain is well known for its high energy demands, specifically in gray matter areas. In white matter tracts, energy consumption is lower. Myelination poses a unique challenge for axonal energy generation where myelin sheaths cover more than 95% of the axonal surface areas.

Oligodendrocytes help support axonal integrity. Oligodendrocytes survive well in the absence of mitochondrial oxidative phosphorylation, and without signs of myelin loss, cell death, neurodegeneration or secondary inflammation.

Glycolysis products of oligodendroglial origin are readily metabolized in axonal mitochondria. Oligodendroglial metabolic support is critical for larger and faster-spiking myelinated axons that also have a higher density of mitochondria. An essential requirement for the direct transfer of energy-rich metabolites from oligodendrocytes to the myelinated axonal compartment is ‘myelinic channels’ within the myelin sheath.

Interactions of oligodendrocytes and myelin with the underlying axon are complex and exceed the transfer of energy-rich metabolites. Continuous turnover of myelin membranes by lipid degradation and fatty acid beta-oxidation in mitochondria and peroxisomes leads to recycling of acetate residues by fatty acid synthesis and membrane biogenesis.

1-s2.0-S0959438823001071-gr2_lrg

In human multiple sclerosis (MS) and its animal model myelin oligodendrocyte glycoprotein-experimental autoimmune encephalomyelitis (MOG-EAE), acute inflammatory demyelination is followed by axonal degeneration in lesion sites that is mechanistically not fully understood. It is widely thought that demyelination and the lack of an axon-protective myelin sheath in the presence of numerous inflammatory mediators are the main causes of axon loss.

But unprotected axons improve rather than worsen the overall clinical phenotype of EAE mice which exhibited the same degree of autoimmunity. Thus, ‘bad myelin is worse than no myelin’ because MS-relevant myelin injuries perturb the integrity of myelinic channels and metabolic support.

Dysfunctional or injured oligodendrocytes that do not allow for compensation by any other cell types turn the affected myelin ensheathment into a burden of the underlying axonal energy metabolism, which causes irreversible axon loss. Any loss of myelin integrity, as seen acutely in demyelinating disorders or more gradually in the aging brain, becomes a risk factor for irreversible neurodegeneration.”

https://www.sciencedirect.com/science/article/pii/S0959438823001071 “Expanding the function of oligodendrocytes to brain energy metabolism”

A 2024 review focused on myelin and oligodendrocyte plasticity:

“This review summarizes our current understanding of how myelin is generated, how its function is dynamically regulated, and how oligodendrocytes support the long-term integrity of myelinated axons.

Apart from its unique ultrastructure, there are several other exceptional features of myelin. One is certainly its molecular composition. Another is its extraordinary stability. This was compellingly illustrated when 5000-year-old myelin with almost intact ultrastructure was dissected from a Tyrolean Ice Man.

Myelin is a stable system in contrast to most membranes. However, myelin is compartmentalized into structurally and biochemically distinct domains. Noncompacted regions are much more dynamic and metabolically active than tightly compacted regions that lack direct access to the membrane trafficking machinery of oligodendrocytes.

The underlying molecular basis for stability of myelin is likely its lipid composition with high levels of saturated, long chain fatty acids, together with an enrichment of glycosphingolipids (∼20% molar percentage of total lipids) and cholesterol (∼40% of molar percentage of total lipids). In addition, myelin comprises a high proportion of plasmalogens (ether lipids) with saturated long-chain fatty acids. In fact, ∼20% of the fatty acids in myelin have hydrocarbon chains longer than 18 carbon atoms (∼1% in the gray matter) and only ∼6% of the fatty acids are polyunsaturated (∼20% in gray matter).

With maturation of oligodendrocytes, the plasma membrane undergoes major transformations of its structure. Whereas OPCs are covered by a dense layer of large and negatively charged self-repulsive oligosaccharides, compacted myelin of fully matured oligodendrocytes lacks most of these glycoprotein and complex glycolipids.

Schematic depiction of an oligodendrocyte that takes up blood-derived glucose and delivers glycolysis products (pyruvate/lactate) via monocarboxylate transporters (MCT1 and MCT2) to myelinated axons. Oligodendrocytes and myelin membranes are also coupled by gap junctions to astrocytes, and thus indirectly to the blood–brain barrier.

oligodendrocyte

Adaptive myelination refers to dynamic events in oligodendroglia driven by extrinsic factors such as experience or neuronal activity, which subsequently induces changes in circuit structure and function. Understanding how these adaptive changes in neuron-oligodendroglia interactions impact brain function remains a pressing question for the field.

Transient social isolation during adulthood results in chromatin and myelin changes, but does not induce consequent behavioral alterations. When mice undergo a social isolation paradigm during early life development, they similarly exhibit deficits in prefrontal cortex function and myelination, but these deficiencies do not recover with social reintroduction. This implicates a critical period for social deprivation effects on myelin dynamics. Experience-dependent changes in myelin dynamics may depend on not only the age, brain region, and cell type studied, but also the specific myelin structural change assessed.

Local synaptic neurotransmitter release along an axon not only affects the number of OPCs and oligodendrocytes associated with that axon and local synthesis of myelin proteins, but also drives preferential selection of active axons for myelination over the ensheathment of electrically silenced neighboring axons. Neuronal activity–induced plasticity may preferentially impact brain regions that remain incompletely myelinated compared to more fully myelinated tracts.

Whereas the myelin sheath has been regarded for a long time as an inert insulating structure, it has now become clear that myelin is metabolically active with cytoplasmic-rich pathways, myelinic channels, for movement of macromolecules into the periaxonal space. The myelin sheath and its subjacent axon need to be regarded as one functional unit, which are not only morphological but also metabolically coupled.”

https://cshperspectives.cshlp.org/content/early/2024/04/15/cshperspect.a041359 “Oligodendrocytes: Myelination, Plasticity, and Axonal Support” (not freely available) Thanks to Dr. Klaus-Armin Nave for providing a copy.

A 2024 rodent study investigated oligodendrocyte precursor cell transcriptional and epigenetic changes:

“We used single-cell RNA sequencing (scRNA-seq), single-cell ATAC sequencing (scATAC-seq), and single-cell spatial transcriptomics to characterize murine cortical OPCs throughout postnatal life. One group (active, or actOPCs) is metabolically active and enriched in white matter. The second (homeostatic, or hOPCs) is less active, enriched in gray matter, and predicted to derive from actOPCs. Relative to developing OPCs, both actOPCs and hOPCs are less active metabolically and have less open chromatin.

In adulthood, these two groups are transcriptionally but not epigenetically distinct, indicating that they may represent different states of the same OPC population. If that is the case, then one model is that the parenchymal environment maintains adult OPCs within an hOPC state, whereas those OPCs recruited into white matter or exposed to demyelinated axons may transition toward an actOPC state in preparation for making new oligodendrocytes. We do not yet know the functional ramifications of these differences, but this finding has clear implications for the development of therapeutic strategies for adult remyelination.

opcs

Another finding is that developing but not adult actOPC chromatin is preferentially open for binding motifs associated with neural stem cells, transit-amplifying precursors, and neurogenesis. Although this may simply reflect their origin as the immediate progeny of neonatal neural precursor cells, it may also explain why developing but not adult OPCs have the capacity to make neurons in culture.

If we could, at least in part, reverse the global chromatin shutdown that occurs between development and adulthood, then perhaps adult OPCs may reacquire the ability to make neurons or become better able to generate new oligodendrocytes for remyelination.”

https://www.cell.com/stem-cell-reports/fulltext/S2213-6711(24)00077-8 “Single-cell approaches define two groups of mammalian oligodendrocyte precursor cells and their evolution over developmental time”

Continued in Part 2.

PXL_20240414_103442372

A good activity for bad weather days

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A free educational series recorded in 2021-2022 available at https://drgoodenowe.com/dr-goodenowes-educational-seminars/ takes the viewer through underlying research and principles of Dr. Goodenowe’s approach to health. It’s advertised as lasting four hours, but took me two days to view.

The series’ discussions and references are background material to better understand later presentations and interviews. Points of interest included:

  • Seminar B100 shows that the metabolomic profile of people who regularly eat broccoli is different than others.
  • B109 clarifies how peroxisomal function is improved through resistance exercise and intermittent fasting.
  • C103 and C104 show how plasmalogens act against neurodegeneration (Parkinson’s disease and multiple sclerosis).

Texts below videos are additional information, not transcripts. C101 text is historically informative.

The B200 ProdromeScan tutorial will take more study. But unlike Labcorp tests, ordering a ProdromeScan requires using a practitioner in Dr. Goodenowe’s network.

I sent the following to Prodrome customer service earlier this month:

Please add me to your approved list for ProdromeScan.

Customer service replied:

“We only add health professionals to an approved list, not individuals.”

I responded:

Good morning. I looked at the websites of doctors who are associated with Dr. Goodenowe who are near me. All of them are too compromised for me to establish a doctor / patient relationship. But I’m glad they left up their blog posts from earlier this decade so I could see who they really were before I reached out to them.

I request an exception to the policy.

Customer service replied:

“There is no exception that can be made to this policy. You need to be a patient of a certified practitioner.”

I’ll escalate my request before my 90-day trial of Prodrome Glia and Neuro products ends so I can get an appropriate metabolomic status. Right now, I won’t involve someone I can’t trust just to know my ProdromeScan information that’s additional to next week’s Labcorp tests.

My treatment-result metabolomic data is probably not mature today on Day 29 of ProdromeGlia and ProdromeNeuro supplementation, resistance exercise, and intermittent fasting. I otherwise wouldn’t have experienced these two events:

I have a quibble with the series’ recommendations for taking N-acetyl cysteine. Relevant views and research:

Switch on your Nrf2 signaling pathway pointed out:

“We use NAC in the lab all the time because it stops an Nrf2 activation. So that weak pro-oxidant signal that activates Nrf2, you switch it off by giving a dose of NAC. It’s a potent antioxidant in that right, but it’s blocking signalling. And that’s what I don’t like about its broad use.”

If someone bombs themself everyday with antioxidants, they’re doing nothing to improve training of their endogenous systems’ defensive functions. What happens when they stop bombing? One example was a 2022 human study that found GlyNAC-induced improvements dissolved back to baseline after supplements stopped.

Also, Precondition your defenses with broccoli sprouts highlighted NAC’s deleterious effects on autophagy and lysosome functions:

“TFEB activity is required for sulforaphane (SFN)-induced protection against both acute oxidant bursts and chronic oxidative stress. SFN-induced TFEB nuclear accumulation was completely blocked by pretreatment of cells by N-acetyl-cysteine (NAC), or by other commonly used antioxidants. NAC also blocked SFN-induced mRNA expression of TFEB target genes, as well as SFN-induced autophagosome formation.”

If a secondary goal of taking NAC per is also necessary for the formation of glutathione, taurine can do that without an antioxidant bomb. Taurine supplementation will free up cysteine to do things other than synthesize taurine, like synthesize glutathione.

PXL_20231123_194849211.MP

Brain restoration with plasmalogens

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In this 2023 presentation for a professional audience, Dr. Dayan Goodenowe showed an example of what could be done (in the form of what he personally did at ages 53-54) to restore and augment brain structure and function over a 17-month period by taking plasmalogens and supporting supplements:

https://drgoodenowe.com/recording-of-dr-goodenowes-presentation-from-the-peptide-world-congress-2023-is-now-available/

Follow the video along with its interactive transcript. Restorative / augmentative supplements included:

1. Nutritional Supplementation Strategy

Forms of MRI used to document brain structure and function changes were:

2. Advanced MRI Technologies

Brain volume decreases are the rule for humans beginning at age 40. Dr. Goodenowe documented brain volume increases, which aren’t supposed to happen, but did per the below slide of overall results:

3. Reversing Brain Shrinkage

“From a global cortical volume and thickness perspective, 17 months of high-dose plasmalogens reversed ~15 years of predicted brain deterioration.”

Specific increased adaptations in brain measurements over 17 months included:

  1. Cortical thickness .07/2.51 = +3%.
  2. White matter microstructure fractional anisotropy +8%.
  3. Nucleus accumbens volume +30%.
  4. Dopaminergic striatal terminal fields’ volume +18%.
  5. Cholinergic cortical terminal fields’ volume +10%.
  6. Occipital cortex volume +10%.
  7. Optic chiasm volume +225%.
  8. Nucleus basalis connectivity.
  9. Neurovascular coupling signal controlled by noradrenaline integrity.
  10. Amygdala volume +4% and its connectivity to the insula, indicating ongoing anxiety and emotional stress response.
  11. Parahippocampus volume +7%.
  12. Hippocampus fractional anisotropy +5%.

No changes:

  1. Amygdala connectivity to the ventral lateral prefrontal cortex, the same part of the brain that relates to placebo effect.
  2. Hippocampus connectivity.

Decreased adaptations in brain measurements included:

  1. White matter microstructure radial diffusivity -10%.
  2. Amygdala connectivity to the anterior cingulate cortex to suppress / ignore / deny anxiety response.
  3. Amygdala connectivity to the dorsal lateral prefrontal cortex.
  4. Entorhinal cortex volume -14%.
  5. Hippocampus volume -6%.
  6. Hippocampus mean diffusivity (white matter improved, with more and tighter myelin) -4%.

The other half of this video was a lively and wide-ranging Q&A session.

The referenced 2023 study of 653 adults followed over ten years showed what brain deterioration could be expected with no interventions. Consider these annual volume decrease rates to be a sample of a control group:

etable 3

https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2806488 “Characterization of Brain Volume Changes in Aging Individuals With Normal Cognition Using Serial Magnetic Resonance Imaging”

Also see a different population’s brain shrinkage data in Prevent your brain from shrinking.

The daily plasmalogen precursor doses Dr. Goodenowe took were equivalent to 100 mg softgel/kg, double the maximum dose of 50 mg softgel/kg provided during the 2022 clinical trial of cognitively impaired old people referenced in Plasmalogens Parts 1, 2, and 3.

He mentions taking 5 ml in the morning and 5 ml at night because he used the Prodrome oil products. 1 ml of a Prodrome oil plasmalogen precursor product equals 900 mg of their softgel product.

“My brain is trying to minimize long-term effects of pain/stress by suppressing my memory of it. But this can only go on for so long before it becomes an entrenched state.

I have solved the sustenance side of the equation. I need to work harder to solve the environmental side.”

While I agree that we each have a responsibility to ourselves to create an environment that’s conducive to our health, the above phenomenon isn’t necessarily resolvable by changing an individual’s current environment. My understanding is that long-term effects of pain, stress, and related human experiences are usually symptoms of causes that started much earlier in our lives.

Adjusting one’s present environment may have immediate results, but probably won’t have much therapeutic impact on long-term issues. Early life memories and experiences are where we have to gradually go in order to stop being driven by what happened back then.

See Dr. Arthur Janov’s Primal Therapy for its principles and explanations. I started Primal Therapy at a similar age, 53, and continued for three years.

Plasmalogens, Part 3

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The 2022 plasmalogen clinical trial mentioned in Parts 1 and 2 bypassed peroxisome metabolism of cognitively impaired people per discussion of the below diagram:

fcell-10-864842-g003

Increasing the body’s fasting state with time-restricted eating, and preventing muscle atrophy with resistance exercise, were offered as the two most important ways to improve peroxisomal function.

I didn’t find any relevant 2023 human studies (where I could access the full study) on different non-drug treatments that I was willing to do. A 2023 review outlined aspects of peroxisomes, to include a few older human studies:

“Peroxisomes are small, single-membrane-bound organelles, which are dynamic and ubiquitous. Peroxisomes directly interact with other organelles, such as endoplasmic reticulum, mitochondria, or lysosomes. Peroxisomes exert different functions in various cells through both catabolic and anabolic pathways.

The main functions of peroxisomes can be categorized as reactive oxygen species (ROS) metabolism, lipid metabolism, and ether-phospholipid biosynthesis. Peroxisomes also play important roles in inflammatory signaling and the innate immune response.”

1-s2.0-S2667325823001425-gr3_lrg

https://www.sciencedirect.com/science/article/pii/S2667325823001425 “Peroxisome and pexophagy in neurological diseases”

1. Since I haven’t recently tried the two main ways to improve peroxisomal function, I’ll give them a go over the next three months:

  • Expect to get my feeding timeframe to within eight hours. Don’t know about making it short like 6 hours, because my first meal of the day is 35 calories of microwaved cruciferous sprouts, then I wait an hour before eating anything else.
  • Resistance exercise progress should be measurable, as I recorded exercises during the first ten weeks of eating broccoli sprouts every day 3.5+ years ago.

2. Don’t know that I’ll recognize any cognitive improvements to the extent I did during Week 9.

  • I don’t have a young brain anymore, and I’m sure some decline could be measured in memory tests. But I’m not going to become a lab rat.
  • There’s an occasional annoyance that’s been going on for some time, especially when I’m distracted. It happens when I think of something to do, and it somehow becomes a short-term memory that I did it, instead of going into a Things To Do queue. It’s largely self-correcting. For example, regardless of what I paid, I’ll drive back to the grocery store self-checkout to retrieve a third bag that didn’t make it home. A pink-haired employee said young people leave their paid-for groceries behind all the time. It’s usually more of a reality disconnect for me than forgetfulness, because I have a memory that I performed the action. Definitely room for improvement.

3. Don’t know that I’d see biochemical changes such as some described in Part 1. Maybe I’ll move up an annual physical to compare it with the last one in May?

  • I already have very little oxidative stress, very little inflammation, low triglycerides, high HDL, and no major improvements are indicated on CBC / CMP / lipid panels.
  • Take supplements to ensure other things like acetylcholine neurotransmitter availability, one-carbon / methylation metabolism, vitamin / mineral adequacy.

4. I started the two Prodrome plasmalogen precursor supplements (ProdromeGlia and ProdromeNeuro) a week ago, and take their standard doses. My thought is that resultant plasmalogens won’t degrade very much if their primary use isn’t to immediately address oxidative stress and inflammation. That could give these extra plasmalogens a chance to make larger homeostatic contributions in myelin and membrane areas.

I don’t expect any particular effects to manifest. But I’m interested to see if these two areas would be affected:

  • My left ulnar nerve has been giving me problems for over five years, and several resistance exercises aggravate it. I’ve had two nerve continuity tests during that time to confirm. Numbness and pain are intermittent, though.
  • I still take acetaminophen several times a day for other pain.

None of the above treatments are specifically indicated. But if time-restricted feeding and/or extra plasmalogens have an effect on left ulnar or other pain, maybe I’ll be able to make better progress on resistance exercise.

Update #1 11/13/2023

Update #2 11/22/2023

Update #3 12/13/2023 comments

Update #4 1/30/2024

Update #5 3/31/2024

Ergothioneine dosing

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Four 2023 papers that outlined or used different ergothioneine doses, starting with a human/rodent study:

“We found that cognitive function and hippocampal neurogenesis were lower in mice fed an ERGO-free diet than in those fed the control diet. Mice fed an ERGO-free diet were orally administered ERGO (0, 2, and 20 mg/kg) for two weeks which reversed these effects.

trkb ratio

Phosphorylated brain-derived neurotrophic factor receptor TrkB, the activated form of TrkB, was also detected in extracellular vesicles (EVs) derived from serum samples of 52 volunteers who had been orally administered ERGO-containing tablets (5 mg/day for 12 weeks). The ratio of serum EV-derived phosphorylated TrkB was significantly higher in the ERGO-treated group than in the placebo-treated group and was positively correlated with both serum ERGO concentrations and several cognitive domain scores from Cognitrax.

cognitrax

The ratio of p-TrkB to TrkB in serum EVs was proposed as a quantitative diagnostic marker of long-term ERGO-induced cognitive improvement.”

https://www.researchsquare.com/article/rs-2626422/v1 “TrkB phosphorylation in serum extracellular vesicles correlates with cognitive function enhanced by ergothioneine in humans”

Human equivalents of all rodent ergothioneine doses were higher than the 5 mg/day for 12 weeks 2020 human study, cited as Reference 21. I couldn’t access that paper, so here’s its Abstract:

Effect of ergothioneine on the cognitive function improvement in healthy volunteers and mild cognitive impairment subjects – a randomized, double-blind, parallel-group comparison study

“These results indicate that continuous intake of ergothioneine improves cognitive function in healthy subjects.”

A rodent study compared effects of a fermented product with 0.1 and 1.0 mg/g (human equivalent 6 mg (1 mg x .081) x  70 kg) ergothioneine doses:

“Our present study demonstrated for the first time the preventive effect of Rice-koji fermented extracts made by Aspergillus oryzae on anxiety, impaired recognition, and nociception using a psychophysically stressed model. Our results also demonstrated preventive effects of ergothioneine (EGT) on stress-induced anxiety- and pain-like behaviors.

Daily administration of High dose Rice-koji or 0.1 mg/kg EGT decreased anxiety- and pain-like behaviors. These findings suggest that inhibitory effects of Rice-koji on psychological stress might be mediated through the actions of EGT.”

https://www.mdpi.com/2072-6643/15/18/3989 “Preventive Roles of Rice-koji Extracts and Ergothioneine on Anxiety- and Pain-like Responses under Psychophysical Stress Conditions in Male Mice”

Here’s one of several reviews that cited a 2017 clinical trial (duplicately Reference 39 and 61 for some reason) of 5 and 25 mg ergothioneine doses:

“In this pharmacokinetic study, forty-five healthy humans received placebo, 5, or 25 mg encapsulated ergothioneine/d for 7 d and were followed up for an additional 4 weeks. Ergothioneine was rapidly absorbed and largely retained by the body, with large increases in plasma ergothioneine levels and only minimal increases (<4 %) in urinary excretion observed. While plasma levels of ergothioneine decreased when supplementation was withdrawn, levels in whole blood continued to increase in a dose–response fashion, reaching maximal levels 3 weeks after withdrawal of supplement, which were sustained at 4 weeks follow-up.

A large difference in basal concentrations of ergothioneine in whole blood was observed. Participants with the highest basal levels of ergothioneine also appeared to take up more of supplemented ergothioneine.”

https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/ergothioneine-an-underrecognised-dietary-micronutrient-required-for-healthy-ageing/92CED7FF201A9FB23BEAFF0D3EAD7316 “Ergothioneine: an underrecognised dietary micronutrient required for healthy ageing?”

Wrapping up with a deep dive into seven mushroom varieties’ compounds:

“Mushrooms contain multiple essential nutrients and health-promoting bioactive compounds, including amino acid L-ergothioneine. We compared metabolomes of fresh raw white button, crimini, portabella, lion’s mane, maitake, oyster, and shiitake mushrooms using untargeted liquid chromatography mass spectrometry (LC/MS)-based metabolomics.

Results indicate significantly higher concentrations of L-ergothioneine in lion’s mane and oyster mushrooms compared to the remaining five mushroom varieties, which had concentrations ranging from 1.94 ± 0.55 to 5.26 ± 1.23 mg/100 g wet weight (mean ± SD). There was also variability in concentration of L-ergothioneine between mushroom varieties of the same farm. Different numbers denote significance (p < 0.05).

foods-12-02985-g008

Mushrooms and their bioactive extracts are considered functional foods. Mushrooms have several bioactive compounds, including polysaccharides, lectins, terpenoids, sterols, and alkaloids, among others, which may positively impact health.

Cell walls of mushrooms contain polysaccharides, including β-glucans and chitin, which positively affect health, through modulating the immune system and protecting the cardiovascular system through improvements in glucose and lipid metabolism. Effects on the cardiovascular system are also attributable to lovastatin and polyphenols, known for their lipid-lowering and antioxidant properties, respectively.

While the 1344 compounds in common among the seven mushroom varieties support some level of similarity, detection of hundreds of unique-to-mushroom-variety compounds and differences in amino acid profiles indicate that not all mushrooms are chemically comparable. Given detection of >400 unique-to-mushroom-variety compounds in lion’s mane, maitake, oyster, and shiitake mushrooms, we suggest further targeted investigations on compounds detected and potential health benefits.”

https://www.mdpi.com/2304-8158/12/16/2985 “Metabolomics Profiling of White Button, Crimini, Portabella, Lion’s Mane, Maitake, Oyster, and Shiitake Mushrooms Using Untargeted Metabolomics and Targeted Amino Acid Analysis”

I eat around 200 grams of mushrooms daily, having temporarily overridden the boredom of eating AGE-less chicken vegetable soup every day. I prep all the top package’s frozen umami bomb (283 grams) and half of the bottom’s fresh mushrooms (340 grams) into the soup:

PXL_20230921_193708552

It makes servings for three days, including one for prep day dinner. I’d guess from “concentrations ranging from 1.94 ± 0.55 to 5.26 ± 1.23 mg/100 g (mean ± SD)” that my daily mushroom ergothioneine dose is around 7 mg ((1.94 mg + 5.26 mg) / 2) = 3.6 mg per 100 grams x 2 (for 200 grams).

Continued in Part 2.

Take Vitamin K2 to protect against aluminum toxicity

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This 2023 rodent study investigated relationships of MK-7 menaquinone, aluminum trichloride, and brain health:

“A variety of endogenous and exogenous agents, such as metals and environmental toxins (aluminum, mercury, etc.), can contribute to neurodegeneration, which is of multifactorial clinical occurrence.

The current study showed that Alzheimer’s Disease (AD)-like condition was induced in mice by AlCl3 treatment affecting spatial and recognition memory. Neuropathological alterations included neuroinflammation, oxidative stress, an increase in brain amyloid β levels, and loss of hippocampal neurons.

Aluminium chloride (AlCl3; 100 mg/kg for 3 weeks orally) was administered to Swiss albino mice to induce neurodegeneration and Vitamin K2 (100 mcg/kg for 3 weeks orally) was applied as treatment. This was followed by behavioral studies to determine memory changes.

Antioxidants like glutathione and SOD were low compared to the control group, while oxidative stress marker MDA was elevated. BDNF levels increased in the Vitamin K2 treated animals, suggesting its neuroprotective functions.

k2 abstract

vitamin K2 BDNF

Vitamin K2 could partially reverse AlCl3-mediated cognitive decline. It increased hippocampal acetylcholine and BDNF levels while reducing oxidative stress, neuroinflammation, and β-amyloid deposition, protecting hippocampal neurons from AlCl3-mediated damage.“

https://link.springer.com/article/10.1007/s10787-023-01290-1 “Vitamin K2 protects against aluminium chloride-mediated neurodegeneration” (not freely available)

This study’s human equivalent Vitamin K2 dose is (100 mcg x .081) x 70 kg = 567 mcg. I’ve taken 600 mcg MK-7 every day for the past two years.

Found out last week that I’ve also been inadvertently dosing myself with aluminum every day. This is the underside of my former 3-year-old drip coffee maker with its cover removed:

PXL_20230813_172709641

I’m certain its aluminum tubing that heats reservoir water started to corrode a long time ago. Currently trying out methods of making aluminum-free coffee.

Reversing biological age in rats

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This 2023 rodent study wrapped together findings of the original study curated in A rejuvenation therapy and sulforaphane, and the second follow-on study mentioned in Signaling pathways and aging. I’ll start by highlighting specifics of the later study:

“Pronounced rejuvenation effects in male rats prompted us to conduct further confirmatory experiments. A particularly important consideration is the effectiveness of E5 with regards to sex, as sex-dependent rejuvenation by some interventions have previously been reported.

To assess E5’s applicability to both male and female Sprague Dawley rats, we studied 12 males (6 treated with E5, 6 with saline) and 12 females (6 treated with E5, 6 with saline). These rats were treated every 45 days with an injection of E5 or saline. Rats were monitored for 165 days, and blood was drawn at six time points: 0, 15, 30, 60, 150 and 165 days from the first injection.

We observed highly significant improvements in TNF alpha and IL-6 levels for both males and females in the blood of E5-injected rats over that of saline controls. We also observed a substantial improvement in grip strength.

Our study shows age reversal effects in both male and female rats, but E5 is more effective in males.”

Another experimental group was started with old rats of both sexes. Using the human / rat relative clock developed in the original study, a human equivalent age to these rats at 26 months old was ((112.7 weeks / 197.6 weeks maximum rat lifespan) x 122.5 years maximum human lifespan) = 69.8 years:

“To validate our epigenetic clock results, we conducted a second set of E5 experiments with Sprague Dawley rats of both sexes. When these rats turned 26 months old, half (9 rats) received the E5 treatment while the other half (8 rats) received only the control treatment (saline injection). We analyzed methylation data from two blood draws: blood draw before treatment (baseline) and a follow up sample (15 days after the E5/saline treatment).”

Treatment measurements were affected by one female control group outlier. Panels F through J were recalculated after removing the outlier to show significant effects in both sexes:

second follow-on results

“A) Final version of the rat clock for blood. Baseline measurement (x-axis) versus follow up measurement (15 days after treatment, y-axis). Points (rats) are colored by treatment: red=treated by E5, black=treated with saline only. Rotated grey numbers underneath each bar reports the group sizes. Each bar plot reports the mean value and one standard error.

B,D,E) Difference between follow up measurement and baseline measurement (y-axis) versus treatment status in B) all rats, D) female rats only, E) male rats only. C) is analogous to B) but uses the pan tissue clock for rats.

Panels in the second row (F,G,H,I,J) are analogous to those in the first row but the analysis omitted one control rat (corresponding to the black dot in the lower right of panel A).”

https://www.biorxiv.org/content/10.1101/2023.08.06.552148v1 “Reversal of Biological Age in Multiple Rat Organs by Young Porcine Plasma Fraction”

A description of how E5 plasma fraction was made starts on page 16 of the *.pdf file. The next E5 study will be done with dogs per July 2023 updates in blog post comments:

“On E5 our entire team is working hard towards the launch of an old Beagle dogs trial this month. We want to make them really young, healthy, happy, and jumping around like 1 and 2 year olds.

Primary endpoint is safety and toxicology to test various dose strengths and frequencies. Secondary endpoints are more than 20.

As you know, we like to test exhaustively to get a sharper perspective of what’s happening. In rat studies we tested 30 biomarkers, including functional. We are especially keen to check kidney markers.

There are two clocks for dogs we are interested in to get third party confirmation of age reversal. Horvath dog clock is ready and GlycanAge dog clock is under construction.

We are requesting all organizations that support pets and aging to financially support their project of building an accurate dog clock. Not only will it help veterinary aging research like ours, but also all the dog owners that may want to know how much improvement their dog received from treatment. Dr. Matt Kaeberlain is an advisor on their project.”

Neuritogenesis

gettingwell4 4-5 stars Advanced knowledge, Acetylcholine, Amygdala, Brain development, Brainstem, Cerebellum, Cerebrum, Dopamine, Epigenetics, Glutamate, Hippocampus, Hypothalamus, Immune system, Limbic system, Lower brain, Memory, Neurochemicals, Stress, Thalamus , , , , , ,

Three 2023 papers on the initial stage of neuronal differentiation, starting with a rodent study of taurine’s effects:

“We aimed to assess the role of taurine (TAU) in axonal sprouting against cerebral ischemic injury, clarify the function of mitochondria in TAU-induced axonal sprouting, and further determine the underlying potential molecular mechanism.

experiment design

We determined that TAU improved motor function recovery and restored neurogenesis in ischemic stroke. This possibly occurred via improvements in mitochondrial function.

We investigated that the Sonic hedgehog (Shh) pathway exerted an important role in these effects. Our study findings highlighted the novel viewpoint that TAU promoted axonal sprouting by improving Shh-mediated mitochondrial function in cerebral ischemic stroke.”

https://www.scielo.br/j/acb/a/nxKvGXGk9g6gRkHxybMfbYJ/?lang=en “Taurine promotes axonal sprouting via Shh-mediated mitochondrial improvement in stroke”

A rodent study investigated effects of a soy isoflavone gut microbiota metabolite:

“Perinatally-infected adolescents living with HIV-1 (pALHIV) appear uniquely vulnerable to developing substance use disorders (SUD). Medium spiny neurons (MSNs) in the nucleus accumbens core (NAcc), an integrator of cortical and thalamic input, have been implicated as a key structural locus for the pathogenesis of SUD.

Treatment with estrogenic compounds (e.g., 17β-estradiol) induces prominent alterations to neuronal and dendritic spine structure in the NAcc supporting an innovative means to remodel neuronal circuitry. The carcinogenic nature of 17β-estradiol, however, limits its translational utility.

Plant-derived polycyclic phenols, or phytoestrogens, whose chemical structure resembles 17β-estradiol may afford an alternative strategy to target estrogen receptors. The phytoestrogen S-Equol (SE), permeates the blood-brain barrier, exhibits selective affinity for estrogen receptor β (ERβ), and serves as a neuroprotective and/or neurorestorative therapeutic for HIV-1-associated neurocognitive and affective alterations.

Beginning at approximately postnatal day (PD) 28, HIV-1 transgenic (Tg) animals were treated with a daily oral dose of 0.2 mg of SE. The SE dose of 0.2 mg was selected for two primary reasons, including:

  1. A dose-response experimental paradigm established 0.2 mg of SE as the most effective dose for mitigating neurocognitive deficits in sustained attention in the HIV-1 Tg rat; and
  2. The dose, which yielded a daily amount of 0.25–1.0 mg/kg/SE (i.e., approximately 2.5–10 mg in a 60 kg human), is translationally relevant (i.e., well below the daily isoflavone intake of most elderly Japanese.

Daily oral treatment continued through PD 90.

j_nipt-2023-0008_fig_002

HIV-1 Tg animals exhibited an initial increase in dendrite length (A) and the number of dendritic spines (B) early in development; parameters which subsequently decreased across time. In sharp contrast, dendrite length and the number of dendritic spines were stable across development in control animals.

Targeting these alterations with the selective ERβ agonist SE during the formative period induces long-term modifications to synaptodendritic structure, whereby MSNs in the NAcc in HIV-1 Tg animals treated with SE resemble control animals at PD 180.”

https://www.degruyter.com/document/doi/10.1515/nipt-2023-0008/html “Constitutive expression of HIV-1 viral proteins induces progressive synaptodendritic alterations in medium spiny neurons: implications for substance use disorders”

A rodent brain cell study investigated soy isoflavones’ effects on a different estrogen receptor:

“We evaluated effects of isoflavones using mouse primary cerebellar culture, astrocyte-enriched culture, Neuro-2A clonal cells, and co-culture with neurons and astrocytes. Soybean isoflavone-augmented estradiol mediated dendrite arborization in Purkinje cells.

These results indicate that ERα plays an essential role in isoflavone-induced neuritogenesis. However, G-protein-coupled ER (GPER1) signaling is also necessary for astrocyte proliferation and astrocyte–neuron communication, which may lead to isoflavone-induced neuritogenesis.

We highlight the novel possibility that isoflavones enhance dendritogenesis and neuritogenesis, indicating that they can be a useful supplementary compound during brain development or in the injured brain.”

https://www.mdpi.com/1422-0067/24/10/9011 “Isoflavones Mediate Dendritogenesis Mainly through Estrogen Receptor α”

Brain endothelial cells

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Six 2023 papers on the subject, starting with a rodent study:

“One of the primary discoveries of our study is that the endothelial cell (EC) transcriptome is dynamically regulated by both aging and heterochronic parabiosis. We found that ECs, when compared with other brain cell types, exhibited one of the highest fractions of aging-related genes that were rescued after heterochronic parabiosis in the old brain, and similarly, the highest fraction of aging-related genes that were disrupted after heterochronic parabiosis in the young brain. This finding supports our previous research that vasculature is strongly affected by aging and disease, and is capable of regrowth after heterochronic parabiosis or systemic GDF11 treatment.

parabiosis

We observed that a subset of ECs was classified as mitogenic. It is reasonable to speculate that the growth of these cells, which is probably prevented or suspended by the inflammatory environment of the aged brain, may be among the cell populations that respond to these interventions.

Although proteostasis in brain ECs has not been thoroughly investigated, they are apparently long-lived cells and, like neurons, might therefore accumulate protein aggregates with age, potentially compromising their function. ECs become senescent with age, but parabiosis may reverse that phenotype as well.

These findings underline the strong susceptibility and malleability of ECs, which are directly exposed to secreted factors in both brain parenchyma and blood, to adapt to changes in their microenvironment. ECs, despite comprising <5% of the total number of brain cells, are a promising and accessible target for treatment of aging and its associated diseases.”

https://www.nature.com/articles/s43587-023-00373-6 “Heterochronic parabiosis reprograms the mouse brain transcriptome by shifting aging signatures in multiple cell types”

A review elaborated on endothelial cell senescence:

“ECs form highly dynamic and differentiated monolayers arranged in a vascular network. Within brain tissue, the ECs of arteries, capillaries, and veins present different molecular characteristics. The main functions of ECs as a major cellular component of the blood-brain barrier (BBB) are to express cell membrane transport proteins, produce inflammatory mediators, deliver nutrients to brain tissue, and prevent drugs and toxins from entering the central nervous system.

ECs are the first echelons of cells affected at the onset of senescence due to their special structural position in the vascular network. Senescent ECs produce reactive oxygen species (ROS), which directly inhibit smooth muscle potassium channels and cause vasoconstriction.

The vascular endothelium is in a constant process of damage and repair, and once damage occurs, ECs replenish themselves to remove damaged cells. EC senescence makes the endothelium less capable of self-repair. With the decline in endothelial function, excess accumulated senescent cells express senescence-associated secretory phenotypes (SASPs), which result in senescence of adjacent cells, and eventually degeneration of vascular function.”

https://www.aginganddisease.org/EN/10.14336/AD.2023.0226-1 “Endothelial Senescence in Neurological Diseases”

A human study investigated above-mentioned differences in brain endothelial cells:

“We performed single nucleus RNAseq on tissue from 32 Alzheimer’s Disease (AD) and non-AD donors each with five cortical regions: entorhinal cortex, inferior temporal gyrus, prefrontal cortex, visual association cortex, and primary visual cortex. Analysis of 51,586 endothelial cells revealed unique gene expression patterns across the five regions in non-AD donors.

Visual cortex areas, which are affected late in AD progression and experience less neurodegeneration, expressed more genes related to vasculogenesis and angiogenesis. Highly vulnerable areas such as the entorhinal cortex expressed more oxidative stress-related genes in normal aged brain, suggesting endothelial dysfunction in this region even in the absence of severe AD pathology.

The present work shows that senescence-related gene signatures are increased across several brain regions, and confirms these changes in endothelial cells in the absence of other vascular cell types. While endothelial cells are not typically associated with protein aggregation, upregulated protein folding pathways suggest that proteostatic stress is a key pathway in this cell type.”

https://www.biorxiv.org/content/10.1101/2023.02.16.528825v1.full “Endothelial Cells are Heterogeneous in Different Brain Regions and are Dramatically Altered in Alzheimer’s Disease”

A human cell study abstract on above-mentioned blood-brain barrier endothelial cells:

“The BBB is a semi-permeable and protective barrier of the brain, primarily composed of endothelial cells interconnected by tight junction proteins, that regulates movement of ions and molecules between blood and neural matter. In pathological conditions such as traumatic brain injury (TBI), disruption of the BBB contributes to leakage of solutes and fluids into brain parenchyma, resulting in onset of cerebral edema and elevation of intracranial pressure.

The objective of this study was to determine upstream regulators of NLRP3 signaling and BBB hyperpermeability, particularly to determine if extracellular adenosine triphosphate (ATP) via P2X7R, a purinergic receptor, promotes NLRP3 inflammasome activation. Extracellular ATP is a major contributor of secondary injuries following TBI.

Our results suggest that extracellular ATP promotes NLRP3 inflammasome activation. Subsequent caspase-1 and MMP-9-mediated tight junction disorganization are major pathways that lead to BBB dysfunction and hyperpermeability following conditions such as TBI.”

https://journals.physiology.org/doi/abs/10.1152/physiol.2023.38.S1.5732827 “Regulation of Blood-Brain Barrier Endothelial Cell Hyperpermeability by NLRP3 Inflammasome Inhibition”

A human study further investigated effects of traumatic brain injury on brain endothelial cells:

“We previously demonstrated that extracellular vesicles (EVs) released from injured brains led to endothelial barrier disruption and vascular leakage. Here, we enriched plasma EVs from TBI patients (TEVs), detected high mobility group box 1 (HMGB1) exposure to 50.33 ± 10.17% of TEVs, and found the number of HMGB1+TEVs correlated with injury severity. We then investigated for the first time the impact of TEVs on endothelial function using adoptive transfer models.

HMGB1 is secreted by activated cells or passively released by necrotic or injured cells. After post-translational modifications, it interacts with receptors such as toll-like receptors (TLRs; e.g., TLRs 2, 4, and 9) and the receptor for advanced glycation end products (RAGE) to trigger multiple signaling pathways and mediate inflammatory and immune responses. Extracellular HMGB1 promotes endothelial dysfunction, leukocyte activation and recruitment, as well as thrombosis.

These results suggest that circulating EVs isolated from patients with TBI alone are sufficient to induce endothelial dysfunction. They contribute to secondary brain injury that are dependent on immunologically active HMGB1 exposed on their surface. This finding provided new insight for development of potential therapeutic targets and diagnostic biomarkers for TBI.”

https://www.sciencedirect.com/science/article/pii/S1043661823001470 “Circulating extracellular vesicles from patients with traumatic brain injury induce cerebrovascular endothelial dysfunction”

To wrap up, eat mushrooms to protect your brain endothelial cells!

“Natural compound ergothioneine (ET), which is synthesised by certain fungi and bacteria, has considerable cytoprotective potential. We previously demonstrated anti-inflammatory effects of ET on 7-ketocholesterol (7KC)-induced endothelial injury in human blood-brain barrier endothelial cells (hCMEC/D3). 7KC is an oxidised form of cholesterol present in atheromatous plaques and sera of patients with hypercholesterolaemia and diabetes mellitus. The aim of this study was to elucidate the protective effect of ET on 7KC-induced mitochondrial damage.

Protective effects of ET were diminished when endothelial cells were coincubated with verapamil hydrochloride (VHCL), a nonspecific inhibitor of the ET transporter OCTN1 (SLC22A4). This outcome demonstrates that ET-mediated protection against 7KC-induced mitochondrial damage occurred intracellularly and not through direct interaction with 7KC.

OCTN1 mRNA expression itself was significantly increased in endothelial cells after 7KC treatment, consistent with the notion that stress and injury may increase ET uptake. Our results indicate that ET can protect against 7KC-induced mitochondrial injury in brain endothelial cells.”

https://www.mdpi.com/1422-0067/24/6/5498 “Protective Effect of Ergothioneine against 7-Ketocholesterol-Induced Mitochondrial Damage in hCMEC/D3 Human Brain Endothelial Cells”

A biomarker for impaired cognitive function?

gettingwell4 4-5 stars Advanced knowledge, Acetylcholine, Dopamine, Epigenetics, Glutamate, Hippocampus, Immune system, Limbic system, Memory, Neurochemicals, Serotonin, Stress , , , ,

This 2023 rodent study investigated associations between a drug, a gut microbiota species, cognitive function, and proinflammatory cytokine interleukin-6:

“We show that gut microbiota is altered by metformin, which is necessary for protection against ageing-associated cognitive function declines in aged mice.

  • Mice treated with antibiotics did not exhibit metformin-mediated cognitive function protection.
  • Treatment with Akkermansia muciniphila improved cognitive function in aged mice.
  • A. muciniphila decreased proinflammatory-associated pathways, particularly that of proinflammatory cytokine interleukin (IL)-6, in both peripheral blood and hippocampal profiles, which was correlated with cognitive function improvement.
  • An IL-6 antibody protected cognitive function, and an IL-6 recombinant protein abolished the protective effect of A. muciniphila on cognitive function in aged mice.

40168_2023_1567_Figa_HTML

A. muciniphila, which is mediated in gut microbiota by metformin, modulates inflammation-related pathways in the host and improves cognitive function in aged mice by reducing proinflammatory cytokine IL-6 both systemically and in the hippocampus. This is direct evidence to validate that gut microbiota mediate the effect of metformin on cognitive improvement.”

https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-023-01567-1 “Akkermansia muciniphila, which is enriched in the gut microbiota by metformin, improves cognitive function in aged mice by reducing the proinflammatory cytokine interleukin-6″

IL-6 may be useful with other biomarkers of impaired cognitive function. It’s too coarse to track improved cognitive function past a certain point, though. Maybe the current IL-6 blood test can be refined as high-specificity CRP and regular CRP blood tests were done?

We don’t need to take this drug or be concerned about this gut bacteria species in order to lower inflammation. Click the IL-6 link above and see blog posts such as Part 2 of Rejuvenation therapy and sulforaphane for other methods.

PXL_20230630_092833465

Nrf2 Week #2: Neurons

gettingwell4 4-5 stars Advanced knowledge, Anterior cingulate cortex, Brain development, Cerebrum, Epigenetics, Hippocampus, Limbic system, Memory, Stress , , , , ,

To follow the Nrf2 Week #1 suggestion that Nrf2 target neurological disorders, this 2023 cell study investigated Nrf2 expression in neurons:

“Oxidative metabolism is inextricably linked to production of reactive oxygen species (ROS), which have the potential to damage all classes of macromolecules. Yet ROS are not invariably detrimental. Several properties make ROS useful signaling molecules, including their potential for rapid modification of proteins and close ties to cellular metabolism.

We used multiple single cell genomic datasets to explore Nrf2 expression and regulation in hundreds of neuronal and non-neuronal cell types in mouse and human. With few exceptions, Nrf2 is expressed at far lower levels in neurons than in non-neuronal support cells in both species.

This pattern is maintained in multiple disease states, and the chromatin accessibility landscape at the Nrf2 locus parallels these expression differences. These results imply that Nrf2 activity is limited in almost all neurons of the mouse and human central nervous system (CNS).

nrf2 expression

We separated cell types into neuron or non-neuronal ‘support’ cell categories. The general ‘support’ term is not meant to minimize the functional relevance of non-neuronal cells in the CNS, but is an umbrella term meant to cover everything from glial cell types (astrocytes, microglia, oligodendrocytes) to endothelial cells.

It is not clear why an important, near ubiquitous cytoprotective transcription factor like Nrf2 remains off in mature neurons, especially considering oxidative stress is a driver of many diseases. The simplest explanation is that Nrf2 activity also disrupts normal function of mature neurons.

ROS play a key role in controlling synaptic plasticity in mature neurons. These activity-dependent changes in synaptic transmission, which are important for learning and memory, are disrupted by antioxidants.

A subset of important Nrf2-targeted antioxidant genes (e.g., Slc3a2, Slc7a11, Nqo1, Prdx1) are also low in neurons. So it is likely that these and/or other Nrf2 targets must remain low or non-ROS-responsive in mature neurons. Future work exploring why this expression pattern persists in mature neurons will inform our models on roles of antioxidant genes in normal neuronal physiology and in neurological disorders.“

https://www.biorxiv.org/content/10.1101/2023.05.09.540014v1.full “Limited Expression of Nrf2 in Neurons Across the Central Nervous System”

PXL_20230520_182827767

Don’t eat yourself into disease, Part 2

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This blog’s 1000th curation is a 2023 rodent study associating gut microbiota, behavior, memory, and food reward:

“Energy intake and energy expenditure is regulated by the hypothalamus, and is referred to as homeostatic regulation of food intake. The reward system is the non-homeostatic regulation of food intake – pleasure-related consumption of foods enriched in fat and sugar. The pleasure is encoded by dopamine release from dopaminergic neurons projecting from the ventral tegmental area to the striatum, the nucleus accumbens, and the prefrontal cortex.

Food reward can be divided into three components – liking, wanting, and learning:

  • Liking refers to food hedonic value;
  • Wanting to the motivational process to seek out and consume certain foods; and
  • Learning to reinforcing conditioning behavior associated with food intake stimulus.

We confirmed that obese mice have a dysregulation of the learning and the wanting components of  food reward. Our previous data showed that the liking component was transferable through fecal material transplantation.

We demonstrated that gut microbes play a role in the regulation of food reward, and could be responsible for compulsive behavior and excessive motivation to obtain sucrose pellets. Moreover, obese gut microbes affected dopaminergic and opioid markers involved in reward system.

We identified 33HPP (produced exclusively by gut bacteria) as particularly increased in mice recipients of gut microbes from obese mice. We were able to demonstrate its effects as key mediator of the gut-brain axis controlling the reward response to palatable food.”

https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-023-01526-w “Obese-associated gut microbes and derived phenolic metabolite as mediators of excessive motivation for food reward”

PXL_20230415_195202937

Eat broccoli sprouts for depression, Part 3

gettingwell4 4-5 stars Advanced knowledge, Cerebrum, Epigenetics, Hippocampus, Hypothalamus, Limbic system, Memory, Stress , , , , ,

Here are two papers published after Part 2 that cited the Part 1 rodent study, starting with a 2023 rodent study performed by several Part 1 coauthors:

“We used a low-dose LPS-induced endotoxaemia model to mimic clinical characteristics of sepsis. We found that adolescent LPS treatment was sufficient to increase levels of inflammatory factor TNF-α in both the medial prefrontal cortex (mPFC) and hippocampus at post-natal day P22.

P21 LPS-treated mice were injected with sulforaphane (SFN) or saline intraperitoneally at P49 and then subjected to subthreshold social defeat stress (SSDS). We found that SFN preventative treatment significantly:

  • Decreased the social avoidance, anhedonia, and behavioural despair detected by the social interaction test, sucrose preference test, tail suspension test, and forced swim test, respectively.
  • Decreased anxiety-like behaviours without affecting locomotor activities.
  • Increased Nrf2 and brain-derived neurotrophic factor (BDNF) levels in the mPFC of P21 LPS-treated mice after SSDS compared with saline control mice.

The above results suggest that activation of the Nrf2-BDNF signalling pathway prevents the effect of adolescent LPS-induced endotoxaemia on stress vulnerability during adulthood.

sulforaphane and stress vulnerability

These results suggest that early adolescence is a critical period during which inflammation can promote stress vulnerability during adulthood. This might be due to increased inflammatory response in the mPFC, and mediated by decreased levels of Nrf2 and BDNF. These findings may shed light on the potential use of SFN as an alternative preventative intervention for inflammation-induced stress vulnerability.”

https://link.springer.com/article/10.1007/s00213-022-06285-4 “Lipopolysaccharide-induced endotoxaemia during adolescence promotes stress vulnerability in adult mice via deregulation of nuclear factor erythroid 2-related factor 2 in the medial prefrontal cortex” (not freely available)

This study demonstrated that adolescent diseases and stresses don’t necessarily develop into adult social problems. A timely intervention may even prevent future adult problems.

The one-time 10 mg/kg sulforaphane dose was the same as Part 1’s dose, a human equivalent of which is (10 mg x .081) x 70 kg = 57 mg.

I’d like to know more about how subjects’ memories of adverse events were retained, and subsequently affected their biology and behavior. Pretty sure limbic structures like the hypothalamus as well as lower brain structures played a part.

A 2022 review summarized what was known up to that time regarding Nrf2 and depression:

“Sulforaphane, an organosulfur compound isolated from Brassicaceae plants, is a potent natural NRF2 activator. Sulforaphane:

  • Exerts antidepressant- and anxiolytic-like activities and inhibits HPA axis and inflammatory response.
  • Has both therapeutic and prophylactic effects on inflammation-related depression.
  • Confers stress resilience.
  • Protects neurons via autophagy and promotes mitochondrial biogenesis by activating Nrf2.”

https://www.sciencedirect.com/science/article/pii/S2213231722002944 “Nrf2: An all-rounder in depression”

PXL_20230306_202857493

Peripheral vs. brain epigenetic measurements

gettingwell4 2-3 stars Required further work, Epigenetics, Immune system , , ,

This 2023 human study investigated associations of peripheral and brain epigenetic measurements:

“Evaluating DNA methylation of brain tissue is challenging owing to the issue of tissue specificity. Consequently, peripheral surrogate tissues are used, resulting in limited progress compared with other epigenetic studies.

Averaging data for each CpG across individuals, saliva–brain correlation (r = 0.90) was higher than that for blood–brain (r = 0.87) and buccal–brain (r = 0.88) comparisons. Among individual CpGs, blood had the highest proportion of CpGs correlated to the brain at nominally significant levels (19.0%), followed by saliva (14.4%) and buccal (9.8%). However, cross-database correlations of correlation coefficients revealed relatively low brain vs. blood: r = 0.27, saliva: r = 0.18, and buccal: r = 0.24.

The majority of methylation in the brain is most likely not synchronized with methylation in the periphery. Despite this, variable CpGs that correlate in the brain and periphery, although in small numbers, may have biological relevance, and could be useful for inferring brain methylation from peripheral tissues.

This study has six major limitations.”

https://www.nature.com/articles/s41398-023-02370-0 “Cross-tissue correlations of genome-wide DNA methylation in Japanese live human brain and blood, saliva, and buccal epithelial tissues”

Real science is messy. Hypotheses are experimentally reevaluated many, many times under varying conditions. I skip over studies where researchers don’t provide meaningful limitation clauses.

PXL_20230305_195313042

Broccoli sprouts activate the AMPK pathway, Part 4

gettingwell4 4-5 stars Advanced knowledge, Cerebrum, Dopamine, Epigenetics, Hippocampus, Immune system, Limbic system, Memory, Neurochemicals, Stress , , , , ,

Today someone viewed the 2020 Part 3 of Broccoli sprouts activate the AMPK pathway which lacked citations at the time. Checking again, here are three citing 2022 papers, starting with a review:

“Nrf2 is an important transcription factor that regulates expression of a large number of genes in healthy and disease states. Nrf2 regulates expression of several key components of oxidative stress, mitochondrial biogenesis, mitophagy, autophagy, and mitochondrial function in all organs of the human body, and in the peripheral and central nervous systems.

Overall, therapeutic drugs including sulforaphane that target Nrf2 expression and Nrf2/ARE pathway are promising. This article proposes additional research in Nrf2’s role within Parkinson’s disease, Huntington’s disease, and ischemic stroke in preclinical mouse models and humans with age-related neurodegenerative diseases.”

https://www.sciencedirect.com/science/article/pii/S1568163722001982 “Role of Nrf2 in aging, Alzheimer’s and other neurodegenerative diseases” (not freely available) Thanks to Dr. P. Hemachandra Reddy for providing a copy.

One of the Part 3 study’s coauthors contributed to this very detailed review:

“Due to observed overlapping cellular responses upon AMPK or NRF2 activation and common stressors impinging on both AMPK and NRF2 signaling, it is plausible to assume that AMPK and NRF2 signaling may interdepend and cooperate to readjust cellular homeostasis.

1-s2.0-S089158492200497X-gr3_lrg

The outcome and underlying signaling events of AMPK-NRF2 crosstalk may diverge between:

  1. in vitro and in vivo studies (one cell type in isolation vs inter-organ crosstalk in living organisms);
  2. Different cell types/organs/organisms of different cultivation conditions, genetic background, age or sex;
  3. Different stress-regimens (chronic vs acute, nature of stress (lipotoxicity, redox stress, xenobiotic, starvation, etc));
  4. Different modes of Nrf2 or AMPK activation and inhibition (genetic vs pharmacological, constitutive vs transient/intermittent, systemic vs organ-specific, electrophilic vs PPI, allosteric vs covalent, or pan vs subtype-specific);
  5. Different target genes with distinct promoter and enhancer structure; or
  6. Different timing of activation.

The latter should deserve increased attention as Nrf2 is one of the most cycling genes under control of the circadian clock. Feeding behavior, metabolism and hence AMPK activity follow and substantiate the biological clock, indicating an entangled circadian regulation of metabolic and redox homeostasis.”

https://www.sciencedirect.com/science/article/pii/S089158492200497X “AMPK and NRF2: Interactive players in the same team for cellular homeostasis?”

A third citing paper was a study of lens cells that provided an example of similar metformin effects noted in Part 2 of Broccoli sprouts activate the AMPK pathway:

“Loss of Nrf2 and Nrf2 antioxidant genes expression and activity in aging cells leads to an array of oxidative-induced deleterious responses, impaired function, and aging pathologies. This deterioration is proposed to be the primary risk factor for age-related diseases such as cataracts.

AMPK regulates energy at physiological levels during metabolic imbalance and stress. AMPK is a redox sensing molecule, and can be activated under cellular accumulation of reactive oxygen species, which are endogenously produced due to loss of antioxidant enzymes.

The therapeutic potential of AMPK activation has context-dependent beneficial effects, from cell survival to cell death. AMPK activation was a requisite for Bmal1/Nrf2-antioxidants-mediated defense, as pharmacologically inactivating AMPK impeded metformin’s effect.

Using lens epithelial cell lines (LECs) of human or mouse aging primary LECs along with lenses as model systems, we demonstrated that metformin could correct deteriorated Bmal1/Nrf2/ARE pathway by reviving AMPK-activation and transcriptional activities of Bmal1/Nrf2, resulting in increased antioxidants enzymatic activity and expression of Phase II enzymes. Results uncovered crosstalk between AMPK and Bmal1/Nrf2/antioxidants mediated by metformin for blunting oxidative/aging-linked pathobiology.”

https://www.mdpi.com/2073-4409/11/19/3021/htm “Obligatory Role of AMPK Activation and Antioxidant Defense Pathway in the Regulatory Effects of Metformin on Cellular Protection and Prevention of Lens Opacity”

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