Cow milk causes disease

This 2021 review followed up Epigenetic effects of cow’s milk and many papers since then:

“Epidemiological studies associate intake of cow milk with an increased risk of diseases, which are associated with overactivated mechanistic target of rapamycin complex 1 (mTORC1) signaling. Milk’s physiological function to maintain high mTORC1 signaling at the beginning of mammalian life turns into adverse health effects when this postnatal endocrine and epigenetic system is not discontinued as designated by physiological processing of the lactation genome.

Milk is a signaling interface between the maternal lactation genome and the infant’s cellular mTORC1 system that orchestrates growth, anabolism, metabolic, immunological, and neurological programming. Pasteurization combined with refrigeration exposed human milk consumers to bioactive milk exosome (MEX)-derived micro-ribonucleic acids (miRs), augmenting milk’s mTORC1 activity compared to boiled, ultra-heat-treated, or fermented milk.

milk-mediated mTORC1 signaling

Milk consumption activates five major pathways stimulating mTORC1 via:

  1. Growth factors, including growth hormone, insulin, and insulin-like growth factor 1;
  2. Amino acids, especially branched-chain amino acids;
  3. Milk fat-derived palmitic acid;
  4. Milk sugar lactose; and
  5. Epigenetic modifiers, especially MEX-derived miRs.

Understanding milk’s interaction with the central hub of metabolic regulation, mTORC1, will open new avenues for prevention of common diseases.”

https://www.mdpi.com/2218-273X/11/3/404/htm “Lifetime Impact of Cow’s Milk on Overactivation of mTORC1: From Fetal to Childhood Overgrowth, Acne, Diabetes, Cancers, and Neurodegeneration”


This reviewer is somewhat of a zealot. Still, he cited 555 references.

His genotype may tolerate lactose, but he didn’t argue for it:

“After breast feeding, mucosal expression of lactase, an intestinal enzyme hydrolyzing lactose into glucose and galactose, is downregulated in all mammals with the exception of Neolithic humans, who developed LCT [lactase gene] mutations allowing persistent lactase expression.

Lactose content of milk makes up around 2–8% by weight. Lactose hydrolysis provides glucose and galactose, which both activate mTORC1:

  • During glucose abundance and glycolysis, sufficient cellular energy is produced in the form of ATP, which suppresses AMPK activity. Aldolase operates as a sensor for glucose availability that directly links glucose shortage to activation of AMPK.
  • Galactose via induction of oxidative stress activates mTORC1. Galactose-induced overactivation of mTORC1 promotes senescence of neural stem cells and aging of mesenchymal stem cells.

Lactobacilli used in food and dairy fermentation increase NRF2 activation, resulting in NRF2-induced sestrin expression, which attenuates mTORC1 activation.”

Eat broccoli sprouts for your hearing

Two 2021 papers, both of which I found by each citing a 2009 Molecular mechanisms underlying cochlear degeneration in the tubby mouse and the therapeutic effect of sulforaphane (not freely available). First was a review:

“Hair cell damage and loss mediated by oxidative stress are important causes of hearing loss. Sensorineural hearing loss is the most common type of hearing loss, including noise induced hearing loss (NIHL), age-related hearing loss (ARHL), and ototoxic hearing loss.

Nrf2 reduces cell damage caused by oxidative stress, and maintains the dynamic balance of systematic redox by inducing and regulating expression of various antioxidant factors. This review summarizes correlation studies of Nrf2 in hearing loss, providing ideas for prevention and treatment of hearing loss with Nrf2 as the target.

fphar-12-620921-g002

There is positive feedback between p62-mediated autophagy and Nrf2. p62 promotes accumulation of Nrf2 and nuclear translocation. Concurrently, increased Nrf2 promotes p62 expression.

How Nrf2 regulates ROS changes in hair cells, and the upstream and downstream regulatory network of Nrf2 in hair cells, are still not fully understood. Studies on early prevention and treatment of hearing loss through the Keap1-Nrf2-ARE [antioxidant response element] signaling axis are still at the exploratory stage.”

https://www.frontiersin.org/articles/10.3389/fphar.2021.620921/full “The Role of Nrf2 in Hearing Loss”


Second paper was a rodent study:

“We examined oxidative stress and antioxidant response of the p62-Keap1-Nrf2 pathway in cochleae during age-related hearing loss (ARHL) and noise-induced hearing loss (NIHL). We elucidated the function of full-length and variant p62/Sqstm1 (referred to here as p62) in regulation of Nrf2 activation.

Cochlear damage was assessed by analyzing auditory brainstem response (ABR) and by counting hair cells (HCs). Malondialdehyde (MDA, a lipid peroxidation product) levels were measured in young and old mice to determine whether oxidative stress contributed to ARHL.

auditory brainstem response

  • (A) Audiometric threshold (dB) determined from click and pure tone evoked ABRs. Thresholds were each significantly different (P < 0.001) between young mice and old mice.
  • (B) HC loss percentage in basal cochlear turns. Significant differences (P < 0.001) were observed between young and old mice.
  • (C) MDA levels in the cochleae of old mice were significantly higher (P = 0.034) than those of young mice.

ROS accumulation is closely related to ARHL and NIHL. The inability of ROS accumulation to activate the Nrf2 antioxidant stress pathway under physiological conditions may be related to alternative splicing of p62 mRNA in cochleae.

However, the agonist of the Nrf2 pathway enhanced Nrf2 nuclear translocation. This suggests a mechanism in which the antioxidant pathway was difficult to be activated in the context of accumulation of ROS.”

https://www.researchsquare.com/article/rs-535219/v1 “New Target of Oxidative Stress Regulation in Cochleae:Alternative Splicing of the p62/Sqstm1 gene”


The study’s two-month-old mice were equivalent to a 20-year-old human. Its 13-to-14-month-old mice were equivalent to humans in their 60s to 70s.

I expected preconditioning to be mentioned in both papers. Maybe these researchers thought it was too obvious and didn’t need to be stated that:

  • Repeated use of a Nrf2 activator produces transient mild stress;
  • Which elicits a stronger response; and
  • Preconditions cells for future stress?

Sulforaphane in the Goldilocks zone and its cited papers exhaustively emphasized preconditioning’s importance. The main thing I’m trying to do with isothiocyanates is to send a weak pro-inflammatory signal to my endogenous ARE system to exercise natural defenses.

Twice-daily drills make me more proficient at responding to actual emergencies. Post-drill, my body recycles material to be ready to respond the next time.

I do the same thing once a day with β-glucan 1,3/1,6 to train my innate immune system. Microphages in my gut are the first responders. Like the very reactive isothiocyanates, I don’t take anything with, or an hour before or after β-glucan 1,3/1,6.

Why tolerate “the antioxidant pathway was difficult to be activated in the context of accumulation of ROS” when a sulforaphane “agonist of the Nrf2 pathway enhanced Nrf2 nuclear translocation”? For all we know, diminished natural defenses and hearing loss may exist to turn old mammals into prey.

Continued in Part 2.

The amino acid ergothioneine

A trio of papers on ergothioneine starts with a 2019 human study. 3,236 people without cardiovascular disease and diabetes mellitus ages 57.4±6.0 were measured for 112 metabolites, then followed-up after 20+ years:

“We identified that higher ergothioneine was an independent marker of lower risk of cardiometabolic disease and mortality, which potentially can be induced by a specific healthy dietary intake.

overall mortality and ergothioneine

Ergothioneine exists in many dietary sources and has especially high levels in mushrooms, tempeh, and garlic. Ergothioneine has previously been associated with a higher intake of vegetables, seafood and with a lower intake of solid fats and added sugar as well as associated with healthy food patterns.”

https://heart.bmj.com/content/106/9/691 “Ergothioneine is associated with reduced mortality and decreased risk of cardiovascular disease”


I came across this study by its citation in a 2021 review:

“The body has evolved to rely on highly abundant low molecular weight thiols such as glutathione to maintain redox homeostasis but also play other important roles including xenobiotic detoxification and signalling. Some of these thiols may also be derived from diet, such as the trimethyl-betaine derivative of histidine, ergothioneine (ET).

image description

ET can be found in most (if not all) tissues, with differential rates of accumulation, owing to differing expression of the transporter. High expression of the transporter, and hence high levels of ET, is observed in certain cells (e.g. blood cells, bone marrow, ocular tissues, brain) that are likely predisposed to oxidative stress, although other tissues can accumulate high levels of ET with sustained administration. This has been suggested to be an adaptive physiological response to elevate ET in the damaged tissue and thereby limit further injury.”

https://www.sciencedirect.com/science/article/pii/S2213231721000161 “Ergothioneine, recent developments”


The coauthors of this review were also coauthors of a 2018 review:

“Ergothioneine is avidly taken up from the diet by humans and other animals through a transporter, OCTN1. Ergothioneine is not rapidly metabolised, or excreted in urine, and has powerful antioxidant and cytoprotective properties.

ergothioneine in foods

Effects of dietary ET supplementation on oxidative damage in young healthy adults found a trend to a decrease in oxidative damage, as detected in plasma and urine using several established biomarkers of oxidative damage, but no major decreases. This could arguably be a useful property of ET: not interfering with important roles of ROS/RNS in healthy tissues, but coming into play when oxidative damage becomes excessive due to tissue injury, toxin exposure or disease, and ET is then accumulated.”

https://febs.onlinelibrary.wiley.com/doi/full/10.1002/1873-3468.13123 “Ergothioneine – a diet-derived antioxidant with therapeutic potential”


I’m upping a half-pound of mushrooms every day to 3/4 lb. (340 g). Don’t think I could eat more garlic than the current six cloves.

PXL_20210606_095517049

I came across this subject in today’s video:

Foods for your vision

This 2021 review by five ophthalmologists and two researchers characterized findings of food effects on human vision:

“The most challenging ocular disorders are uncorrected / under-corrected refractive errors, ocular surface dysfunction / dry eye disease, cataracts, glaucoma, diabetic retinopathy (DR), and age-related macular degeneration (AMD):

  • Severe visual impairment and blindness due to cataract or refractive error constitutes half of all global cases;
  • Glaucoma is the most common cause of irreversible blindness;
  • DR is the first cause of visual disability in working-age adults; and
  • AMD is the first cause of blindness in the elderly.

We identify directions for further research on:

  • The role of diet and nutrition in eyes and vision;
  • Potential antioxidant, anti-inflammatory, and neuroprotective effects of natural food (broccoli, saffron, tigernuts and walnuts);
  • The Mediterranean Diet; and
  • Nutraceutic supplements that may supply a promising and highly affordable scenario for patients at risk of vision loss.

We improve understanding of natural food nutritional hallmarks, benefits of the MedDiet, and appropriate oral supplements with vitamins, carotenoids and PUFAs for better eye and vision care.”

https://www.mdpi.com/2304-8158/10/6/1231/htm “Searching for the Antioxidant, Anti-Inflammatory, and Neuroprotective Potential of Natural Food and Nutritional Supplements for Ocular Health in the Mediterranean Population”


eyes

🙂

The next phase of reversing aging and immunosenescent trends

Dr. Greg Fahy earlier this week provided an update on the November 2020 TRIIM-X follow-on to the September 2019 TRIIM curated in Reversal of aging and immunosenescent trends. Emphasis was on reproducibility:

23:45 Dr. Steve Horvath reanalyzed TRIIM for the plasma portion of Levine’s PhenoAge epigenetic clock. Results were congruent with four other epigenetic clocks showing a 2.5 year reduction of biological age.

39:20 TRIIM-X preliminary results started with C-Reactive protein.

43:05 No backsliding in epigenetic age deceleration between TRIIM and TRIIM-X!

continued epigenetic age deceleration

55:07 Q & A session starts with how TRIIM-X controls for supplements. Answers for resveratrol and calorie restriction, emphasizing that CR doesn’t reverse aging.

1:10 TRIIM-X took photos of subjects’ hair at baseline!


Great update! The last 20 minutes emphasized a need for capital in aging research. TRIIM-X has another 1.5 years to go, and other aging research projects needing funding were mentioned.

Don’t know what happened to the unmentioned 3000 IU vitamin D and 50 mg zinc recommendations of TRIIM. So I asked. Dr. Fahy replied:

“They are still there! Just not mentioned!”

Thought briefly about enrolling in TRIIM-X, but there’s no way anyone but me gets to experiment with my body.

Vitamin K2 – What can it do?

A trio of papers on Vitamin K2, the first being a 2021 review that emphasized dual effects:

“Osteoporosis (OP) is the most common bone disease that affects elderly men and women. It is a metabolic skeletal disorder caused by an imbalance between bone formation and resorption, leading to a loss of bone mass and quality, skeletal structure deterioration, and an increased risk of fractures.

Vascular calcification is defined as ectopic deposition of mineral matrix in vessel wall. It occurs prevalently in aging and primary chronic conditions (hypertension, diabetes mellitus, and chronic kidney disease), representing an important risk factor for cardiovascular morbidity and mortality.

Studies have provided support for a close link between bone and vascular health. Findings suggest that bone loss in OP may promote and increase the risk of cardiovascular events and vascular atherosclerosis.

Vitamin K2 is involved in a phenomenon in which a low calcium deposition in bone tends to be associated with a parallel increase of calcium deposition in vessel wall as a consequence of impaired calcium metabolism. Most production of Vitamin K2 in humans takes place in intestines. However, the amount derived from intestinal bacteria is poorly absorbed, and is not able to reach concentrations required to exert physiological functions.

Vitamin K2‘s ability to reduce loss of bone mineral density and fracture risk, as well as to improve bone quality, has been described by several clinical studies, which have confirmed that osteocalcin (OC) γ-carboxylation is the main mechanism of action through which this natural compound is able to improve bone health. Clinical evidence suggests an analogous protective role of Vitamin K2 at the vascular level, emphasizing a strict association between:

  • Vitamin serum level;
  • Matrix gla protein (MGP) γ-carboxylation levels;
  • Reduction of vascular smooth muscle cells osteogenic trans-differentiation; and
  • Possible risk of cardiovascular events.”

https://www.mdpi.com/2072-6643/13/4/1222/htm “The Dual Role of Vitamin K2 in ‘Bone-Vascular Crosstalk’: Opposite Effects on Bone Loss and Vascular Calcification”


A second 2021 review emphasized aging:

“Vitamin K can:

  • Carboxylate OC (a protein capable of transporting and fixing calcium in bone);
  • Activate MGP (an inhibitor of vascular calcification and cardiovascular events); and
  • Carboxylate Gas6 protein (involved in brain physiology and a cognitive decline and neurodegenerative disease inhibitor).

By improving insulin sensitivity, Vitamin K lowers diabetes risk. It also exerts antiproliferative, proapoptotic, autophagic effects, and has been associated with a reduced risk of cancer.

The most common [Vitamin K2] subtypes in humans are the short-chain MK[menaquinone]-4, which is the only MK produced by systemic conversion of phylloquinone [Vitamin K1] to menaquinone, and MK-7 through MK-10, which are synthesized by bacteria. The main sources of Vitamin K2 are fermented foods, cheeses, eggs, and meats.”

https://www.mdpi.com/2076-3921/10/4/566/htm “The Role of Vitamin K in Humans: Implication in Aging and Age-Associated Diseases”


The third paper – somehow not cited by these two reviews – was a 2006 human study that performed four experiments:

“The synthetic short-chain vitamin K1 is commonly used in food supplements, but recently the natural long-chain MK-7 has also become available as an over-the-counter supplement. The purpose of this paper was to compare in healthy volunteers absorption and efficacy of K1 and MK-7.

Serum vitamin K species were used as a marker for absorption and OC carboxylation as a marker for activity. Both K1 and MK-7 were absorbed well, with peak serum concentrations at 4 hours after intake.

A major difference was:

  • Very long half-life time of MK-7, resulting in much more stable serum levels; and
  • Accumulation of MK-7 to higher levels (7- to 8-fold) during prolonged intake.

MK-7 induced more complete carboxylation of OC.

Vitamin K2 vs K1

Accumulation and efficacy of K vitamins during long-term daily administration. Participants received in a crossover design either K1 (○) or MK-7 (•) or placebo; in the latter case only K1 (▴) could be detected.

  • (A) Circulating levels of vitamin K; baseline levels for K1 were subtracted; no MK-7 could be detected at baseline.
  • (B) Ratio between circulating carboxylated and undercarboxylated osteocalcin (cOC/ucOC); at baseline the ratio was 1.74 for MK-7, 1.8 for K1, and 1.7 for the placebo group.

MK-7 accumulated during the first 2 weeks until it reached a plateau level of about 10 nM (6 μg/L), whereas K1 remained slightly above placebo values during the entire study period. Efficacy of both K vitamins for OC carboxylation was monitored using the ratio between circulating cOC and ucOC, and it turned out that within 3 days both vitamins had induced increased cOC.

But only by taking MK-7 did the effect continue to increase during the entire study period.

Taken together, these data demonstrate considerable differences between MK-7 and K1:

  • Higher and more stable serum levels are reached with MK-7; and
  • MK-7 has a higher efficacy in both hepatic and extrahepatic protein carboxylation.”

https://ashpublications.org/blood/article/109/8/3279/23729/Vitamin-K-containing-dietary-supplements “Vitamin K–containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7″


I’ve tried various things over the years to address hypertension. I stopped high blood pressure medications briefly to see if each intervention worked. They all haven’t, presumably because I didn’t address causes.

More recently, I broke my left big toe on furniture while walking around in the dark last month, and haven’t recovered. No pictures from walking on the beach at sunrise because it still isn’t possible. 😦

A link between these two health conditions could be Vitamin K2. I don’t eat fermented foods because of their high sodium, or dairy products, and haven’t supplemented Vitamin K2.

Next week I’ll start a 300 μg MK-7 daily dose. Current Vitamin D3 dose is 3800 IU, compared to the second paper of Part 2 of Vitamin K2 – What can it do? which is 400 μg MK-7 and 3200 Vitamin D3.

Astaxanthin bioavailability

By request, research on astaxanthin bioavailability. I used a “astaxanthin” “bioavailability” “quinone reductase” 2021 search term, and read citing papers.

“The bioaccessibility, bioavailability, and antioxidative activities of three astaxanthin geometric isomers were investigated using an in vitro digestion model.

  • 13Z-Astaxanthin showed higher bioaccessibility than 9Z- and all-E-astaxanthins during in vitro digestion, and
  • 9Z-astaxanthin exhibited higher transport efficiency than all-E- and 13Z-astaxanthins.

These might explain why 13Z- and 9Z-astaxanthins are found at higher concentrations in human plasma than all-E-astaxanthin.

9Z- and 13Z- astaxanthins exhibited a higher protective effect than all-E-astaxanthin against oxidative stress.”

https://pubs.acs.org/doi/10.1021/acs.jafc.7b04254 “Bioaccessibility, Cellular Uptake, and Transport of Astaxanthin Isomers and their Antioxidative Effects in Human Intestinal Epithelial Caco-2 Cells” (2017, not freely available)


jf1c00087_0005

“Astaxanthin with a high proportion of Z-isomer (especially rich in 9Z- and 13Z-isomers) was prepared from (all-E)-astaxanthin by thermal treatment and solid–liquid separation. Z-isomer-rich astaxanthin diet resulted in higher levels of astaxanthin in blood and many tissues (in particular, skin, lung, prostate, and eye) compared to all-E-isomer-rich diet.

Z-isomer-rich diet enhanced the level of 13Z-isomer in blood and tissues rather than that of 9Z-isomer. (13Z)-astaxanthin would have higher bioavailability and tissue accumulation than other isomers.”

https://pubs.acs.org/doi/10.1021/acs.jafc.1c00087Z-Isomers of Astaxanthin Exhibit Greater Bioavailability and Tissue Accumulation Efficiency than the All-E-Isomer” (2021, not freely available)


“Astaxanthin is highly susceptible to light, oxygen, and heat stress degradation. In addition, poor water solubility and bioavailability limit its efficacy in vivo. Investigating novel astaxanthin delivery systems is necessary in order to solve these drawbacks.”

https://www.mdpi.com/1420-3049/24/14/2640/htm “The Neuroprotective Effects of Astaxanthin: Therapeutic Targets and Clinical Perspective” (2019)


“Astaxanthin Z-isomers potentially have greater bioavailability and biological activity than (all-E)-astaxanthin. However, stability of Z-isomers is lower than all-E-isomer, which is a serious problem affecting its practical use.

In this study, we investigated impacts of different suspension media (oils and fats) and additives on astaxanthin isomer stability.

  • Z-isomers of astaxanthin isomerized to all-E-isomer during storage.
  • When soybean and sunflower oils were used as the suspension medium, astaxanthin isomers were hardly degraded. However the total Z-isomer ratio decreased from ~80% to ~50% during 6-week storage at 30 °C.
  • (9Z)-astaxanthin showed higher stability than 13Z- and 15Z-isomers.”

https://www.sciencedirect.com/science/article/abs/pii/S0308814621003770 “Evaluation and improvement of storage stability of astaxanthin isomers in oils and fats” (2021, not freely available)


I looked for but didn’t find a graph similar to this one that comparatively plotted astaxanthin:

OMCL2019-2716870.006

I also didn’t find recent human studies.

It seems that a special delivery system is required for taking astaxanthin as a supplement. It would require investigating manufacturers’ claims about isomer content and stability.

Eating colorful seafood is another way to get astaxanthin. Don’t know about eating raw or dried algae.

Ride the waves of gene expression with betaine

This 2021 cell study investigated a dietary supplement’s role in preventing nerve disease:

“A loss of epigenetic control has been implicated in development of neurodegenerative diseases. Previous studies have implicated aberrant DNA and histone methylation in multiple sclerosis (MS) disease pathogenesis.

We have previously reported that methyl donor betaine is depleted in MS and is linked to changes in histone H3 trimethylation (H3K4me3) in neurons. We have also shown that betaine increases histone methyltransferase activity by activating chromatin bound betaine homocysteine S-methyltransferase (BHMT).

A hallmark of MS is the death of oligodendrocytes, the cells responsible for wrapping axons in myelin in the central nervous system and maintaining a healthy sheath. In demyelinating diseases like MS, oligodendrocyte progenitor cells (OPCs) fail to differentiate and make more myelin, resulting in sclerotic lesions.

Promoting differentiation of OPCs and generation of myelin is of great interest as a novel MS therapy. Waves of gene regulation (repression and activation) need to occur to promote myelination.

This BHMT-betaine methylation pathway ensures availability of S-adenosylmethionine (SAM) for a variety of DNA and histone methylation processes. OPC survival and differentiation are dependent upon DNA and histone methylation, and both processes require SAM.

journal.pone.0250486.g001

BHMT uses betaine to remethylate homocysteine to methionine. Betaine can be taken in through the diet or synthesized through the oxidation of choline in mitochondria.

We demonstrated that oligodendrocyte gene expression can be modulated by betaine supplementation through the BHMT-betaine methylation pathway. Our study suggests that dietary betaine supplementation may prove to be a therapeutic agent for MS and other demyelinating disorders.”

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0250486 “The BHMT-betaine methylation pathway epigenetically modulates oligodendrocyte maturation”


I started taking betaine 16 years ago. Didn’t know of these effects until reading this study.

Treating psychopathological symptoms will somehow resolve causes? had more on betaine (aka trimethyl glycine). Current dose is 1.5 grams twice daily.

Are rodent models of human neurodegenerative diseases realistic?

This 2020 stem cell review argued against rodent models of human neurodegenerative diseases:

“Neuronal loss is not caused solely by intrinsic degenerative processes but rather via impaired interactions with surrounding glia and other brain cells. Dysfunctional astrocytes do not provide sufficient nutrients and antioxidants to neurons, while dysfunctional microglia cannot efficiently clear pathogens and cell debris from extracellular space, resulting in chronic inflammatory processes in the brain.

Human glia, especially astrocytes, differ significantly in morphology and function from their mouse counterparts. Recent advances in stem cell technology make it possible to reprogram human patients’ somatic cells to induced pluripotent stem cells (iPSC) and differentiate them further into patient‐specific glia and neurons, thus providing a source of human brain cells.

stem3309-fig-0002-m

Astrocytes do not efficiently utilize energy resources and cannot provide adequate metabolic support to neurons. A coculture of healthy human neurons with diseased astrocytes impaired neuronal calcium responses to glutamate and γ‐aminobutyric acid (GABA) as compared to coculture with healthy human astrocytes.

Treatment with sulforaphane:

  • Normalized basal level glycolysis;
  • Decreased basal level Aβ42 secretion; as well as
  • Ameliorated inflammatory response to pro‐inflammatory cytokines TNF-α and IL1-β in PSEN1 mutant iPSC astrocytes.

It is essential to make sure that what we see in the dish is the real patient‐specific phenotype. Transplantation of human brain organoids containing microglia into mice could provide a novel tool for drug screening in vivo.”

https://stemcellsjournals.onlinelibrary.wiley.com/doi/full/10.1002/stem.3309 “Metabolic and immune dysfunction of glia in neurodegenerative disorders: Focus on iPSC models”


This review’s thesis seems plausible. However, one problem with in vitro stem cell studies is that they often don’t have a control group.

Red cabbage pigments and the brain

This 2020 sheep study measured red cabbage anthocyanin concentrations:

“Study aim was to determine whether strongly bioactive hydrophilic red cabbage anthocyanins cross the blood-cerebrospinal fluid barrier (blood-CSF barrier) and whether there is a selectivity of this barrier towards these compounds.

The blood-CSF barrier, apart from the vascular blood-brain barrier, is the second important barrier. Despite very tight connections between endothelial cells of blood vessels of the choroid plexus, blood-CSF barrier allows selective passing of substances from blood to CSF, which is considered as a medium actively involved in transport of information to nerve cells.

Uncharged, lipophilic, and small-sized substances (≤ 600 Da) can cross the brain barriers without major obstacles thanks to diffusion. The rate of these substances’ penetration into brain tissue is directly proportional to their lipid solubility, and inversely proportional to particle size. Hydrophilic substances require special carriers.

The average percentage level of native anthocyanins over the whole experiment was almost 39.5%, while their metabolites constituted just over 60.5%. However, the proportion of native forms vs. metabolites did not develop identically:

  1. Early term (0.5-4 hrs) was distinguished by native derivatives (> 76%).
  2. Second period (4.5 h) had a similar contribution of native anthocyanins (49.85%) and their metabolites (50.15%).
  3. Third interval (5.0-10 h) more than 87% of anthocyanins were metabolites.

For comparison, a human experiment showed only one period with maximum blood plasma anthocyanins concentration (2 h) after red cabbage consumption.

Only one of 17 native anthocyanins found in blood plasma was detected in CSF. Eleven of 17 metabolites found in blood were identified in CSF.

sheep csf cyanins

Due to their hydrophilic nature and considerable size (≥ 611 Da), there seems to be no possibility to use diffusion for permeation of red cabbage anthocyanins through the blood-CSF barrier. These pigments may pass through this barrier only by the use of special carriers. Other mechanisms of anthocyanins permeation through blood-CSF barrier cannot be eliminated.

Two maximal values of total anthocyanins concentration appeared in both blood and CSF. When the pool of cyanidin compounds available in blood became depleted, the decline of total anthocyanin concentration in CSF was also noted.

Nonacylated cyanidin derivatives penetrated the blood-CSF barrier, but acylated cyanidin derivatives did not. A significantly higher proportion of cyanidin sulfate forms in CSF (31%) compared to blood plasma (9%).

Further targeted studies are needed to determine which paths of permeation via blood-CSF barrier are actually responsible for anthocyanins passing, as well as what mechanisms are present during these processes. In addition, it is worth remembering that low molecular weight compounds formed mainly by colonic microbiota are very important metabolites of anthocyanins, and could be relevant in the context of permeation through brain barriers.”

https://pubs.acs.org/doi/10.1021/acs.jafc.0c03170 “The Blood–Cerebrospinal Fluid Barrier Is Selective for Red Cabbage Anthocyanins and Their Metabolites” (not freely available)


Don’t understand why this study hasn’t been cited even once. These researchers’ methods could be performed with broccoli and other red cabbage compounds.

Chew it!

This 2020 human study examined associations between food consumption and chewing difficulty:

“Masticatory function influences not only control of chewing frequency and pressure, but also quality of life through food intake. Reduced food intake caused by chewing difficulty results in loss of eating pleasure and nutritional imbalance.

Chewing difficulty (DC) has been related to brain-related diseases such as cognitive impairment, cerebrovascular disorder, and Parkinson’s disease, increase in occurrence of diseases such as muscular dystrophy, aging acceleration, stomach, and kidney dysfunction due to reduced digestive enzyme secretion, and depression.

Subjects were divided into not difficult in chewing (NDC) and DC groups, with 24.17% being classified into DC. Average age of all subjects (n = 20,959 adult subjects aged between 19 and 64 yrs plus older) was 50.67 yrs. Average age of DC (60.5 yrs) was about 13 yrs older than NDC (47.5 yrs old).

Males and females consumed 35 and 37 items less frequently than the other sex, respectively:

nrp-14-637-g001

Subjects over 65 yrs who had chewing difficulty were 45.4% whereas that of adults was 24.3%. Items known to contain relatively high dietary fiber content or a high content of connective tissues were considered as foods to avoid by those with chewing difficulty due to strong or hard texture.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7683204/ “Food consumption frequency of Korean adults based on whether or not having chewing difficulty using 2013–2016 KNHANES by sex-stratified comparative analysis”


I’d like to know more about subjects who had unresolved dental problems. This study focused on age and sex, but I’ve known twenty-somethings who had problems such as false teeth and dentures.

I go to a dentist twice a year. Don’t think I’d make my gut microbiota happy with Avena nuda oats, broccoli and oat sprouts, and AGE-less chicken vegetable soup if I had dental problems.

Every hand’s a winner, and every hand’s a loser

Another great blog post Know When To Fold ‘Em by Dr. Paul Clayton:

“Newly formed proteins entering the endoplasmic reticulum must be correctly folded to achieve their final form and function. This is a complex procedure with a failure rate of over 80%.

When metabolism is sufficiently skewed, accuracy of protein folding in the endoplasmic reticulum falls below an already low baseline of 20%. Accumulation of misfolded or unfolded proteins in the endoplasmic reticulum then triggers stress.

Integrated Stress Response (ISR) is something that cells do when they are affected by major stressors:

  • ISR turns down global protein synthesis, which is designed to kill virally infected or cancerous cells. If it kills the cancer cell or virally infected cell, that is the end of it.
  • If the stressor is in the heat / hypoxia / nutrient group, however, ISR effectively puts a cell into dark mode until hard times are over. Once the stressor has passed, a cell can then start to recover and return to homeostatic health.
  • But if the stressor is sustained, a low-grade ISR continues to smolder away, causing long-term impairment locally and ultimately systemically. Accumulation of misfolded or unfolded proteins activates ISR, leading to a down-regulation of protein synthesis, and increasing protein folding and degradation of unfolded proteins.

This is analogous to inflammation. Acute inflammatory responses to a pathogen or to tissue damage are entirely adaptive, and essential. Chronic inflammation, on the other hand, causes local and eventually systemic damage if left unchecked for long enough.”


A 2020 rodent study was cited for “reversing age-related cognitive decline”:

“This suggests that the aged brain has not permanently lost cognitive capacities. Rather, cognitive resources are still there, but have been somehow blocked, trapped by a vicious cycle of cellular stress.

Our work with ISR inhibition demonstrates a way to break that cycle, and restore cognitive abilities that had become walled off over time.

stress response inhibitor effects

If these findings in mice translate into human physiology, they offer hope and a tangible strategy to sustain cognitive ability as we age.”

https://elifesciences.org/articles/62048 “Small molecule cognitive enhancer reverses age-related memory decline in mice”


I’m curious as to why sulforaphane hasn’t been mentioned even once in Dr. Paul Clayton’s blog, which started three years ago. Do hundreds of sulforaphane studies performed in this century not contribute to his perspective? Polyphenols are mentioned a dozen times, yet they are 1% bioavailable compared with 80% “small molecule” sulforaphane.

Advice from the song depends on your definition of money:

“Know when to walk away
Know when to run
Never count your money
When you’re sitting at the table”

Gut microbiota topics

Here are thirty 2019 and 2020 papers related to Switch on your Nrf2 signaling pathway topics. Started gathering research on this particular theme three months ago.

There are more researchers alive today than in the sum of all history, and they’re publishing. I can’t keep up with the torrent of interesting papers.

on

2020 A prebiotic fructo-oligosaccharide promotes tight junction assembly in intestinal epithelial cells via an AMPK-dependent pathway

2019 Polyphenols and Intestinal Permeability: Rationale and Future Perspectives

2020 Prebiotic effect of dietary polyphenols: A systematic review

2019 Protease‐activated receptor signaling in intestinal permeability regulation

2020 Intestinal vitamin D receptor signaling ameliorates dextran sulfate sodium‐induced colitis by suppressing necroptosis of intestinal epithelial cells

2019 Intestinal epithelial cells: at the interface of the microbiota and mucosal immunity

2020 The Immature Gut Barrier and Its Importance in Establishing Immunity in Newborn Mammals

2019 Prebiotics and the Modulation on the Microbiota-GALT-Brain Axis

2019 Prebiotics, Probiotics, and Bacterial Infections

2020 Vitamin D Modulates Intestinal Microbiota in Inflammatory Bowel Diseases

2020 Microbial tryptophan metabolites regulate gut barrier function via the aryl hydrocarbon receptor

2019 Involvement of Astrocytes in the Process of Metabolic Syndrome

2020 Intestinal Bacteria Maintain Adult Enteric Nervous System and Nitrergic Neurons via Toll-like Receptor 2-induced Neurogenesis in Mice (not freely available)

2019 Akkermansia muciniphila ameliorates the age-related decline in colonic mucus thickness and attenuates immune activation in accelerated aging Ercc1−/Δ7 mice

2020 Plasticity of Paneth cells and their ability to regulate intestinal stem cells

2020 Coagulopathy associated with COVID-19 – Perspectives & Preventive strategies using a biological response modifier Glucan

2020 Synergy between Cell Surface Glycosidases and Glycan-Binding Proteins Dictates the Utilization of Specific Beta(1,3)-Glucans by Human Gut Bacteroides

2020 Shaping the Innate Immune Response by Dietary Glucans: Any Role in the Control of Cancer?

2020 Systemic microbial TLR2 agonists induce neurodegeneration in Alzheimer’s disease mice

2019 Prebiotic supplementation in frail older people affects specific gut microbiota taxa but not global diversity

2020 Effectiveness of probiotics, prebiotics, and prebiotic‐like components in common functional foods

2020 Postbiotics-A Step Beyond Pre- and Probiotics

2019 Pain regulation by gut microbiota: molecular mechanisms and therapeutic potential

2020 Postbiotics: Metabolites and mechanisms involved in microbiota-host interactions

2020 Postbiotics against Pathogens Commonly Involved in Pediatric Infectious Diseases

2019 Glutamatergic Signaling Along The Microbiota-Gut-Brain Axis

2019 Lipoteichoic acid from the cell wall of a heat killed Lactobacillus paracasei D3-5 ameliorates aging-related leaky gut, inflammation and improves physical and cognitive functions: from C. elegans to mice

2020 Live and heat-killed cells of Lactobacillus plantarum Zhang-LL ease symptoms of chronic ulcerative colitis induced by dextran sulfate sodium in rats

2019 Health Benefits of Heat-Killed (Tyndallized) Probiotics: An Overview

2020 New Horizons in Microbiota and Metabolic Health Research (not freely available)

Go with the Alzheimer’s Disease evidence

This 2021 study investigated gut microbiota differences between 100 AD patients and 71 age- and gender-matched controls:

“Structural changes in fecal microbiota were evident in Chinese AD patients, with decreased alpha-diversity indices and altered beta-diversity ones, evidence of structurally dysbiotic AD microbiota.

Interestingly, traditionally beneficial bacteria, such as Bifidobacterium and Akkermansia, increase in these AD patients while Faecalibacterium and Roseburia decrease significantly. Different species of Bifidobacterium may have different effects that can explain why Bifidobacterium spp. are commonly associated with healthy and diverse microbiota but sometimes also isolated in other conditions. We needed to re-examine the therapeutic potential of Bifidobacterium in terms of maintaining cognitive function and treating dementia.

Surprisingly, our data indicate that Akkermansia was among the most abundant genera in AD-associated fecal microbiota. Similar to Bifidobacterium, Akkermansia was negatively correlated with clinical indicators of AD, such as MMSE, WAIS, and Barthel, and anti-inflammatory cytokines such as IFN-γ.

Based on our present observations, Akkermansia cannot always be considered a potentially beneficial bacterium. It might be harmful for the gut–brain axis in the context of AD development in the elderly.

Aging is associated with an over-stimulation of both innate and adaptive immune systems, resulting in a low-grade, chronic state of inflammation defined as inflammaging. This can increase gut permeability and bacterial translocation.

Characteristics of AD microbial profiles changed from butyrate producers, such as Faecalibacterium, into lactate producers, such as Bifidobacterium. These alterations contributed to shifts in metabolic pathways from butyrate to lactate, which might have participated in pathogenesis of AD. Specific roles of AD-associated signatures and their functions should be explored in further studies.”

https://www.frontiersin.org/articles/10.3389/fcell.2020.634069/full “Structural and Functional Dysbiosis of Fecal Microbiota in Chinese Patients With Alzheimer’s Disease”


The control group’s 73-year-olds were better off than AD patients. How were they compared with their previous life stages?

Since we’re all aging, how do we each prepare ourselves? I’ll return to evidence including 2020 A rejuvenation therapy and sulforaphane, recently amplified in Part 2 of Switch on your Nrf2 signaling pathway:

“A link between inflammation and aging is the finding that inflammatory and stress responses activate NF-κB in the hypothalamus and induce a signaling pathway that reduces production of gonadotropin-releasing hormone (GnRH) by neurons.

The case is particularly interesting when we realize that the aging phenotype can only be maintained by continuous activation of NF-κB. So here we have a multi-level interaction:

  1. Activation of NF-κB leads to
  2. Cellular aging, leading to
  3. Diminished production of GnRH, which then
  4. Acts (through cells with a receptor for it, or indirectly as a result of changes to GnRH-receptor-possessing cells) to decrease lifespan.

Cell energetics is not the solution, and will never lead to a solution because it makes the assumption that cells age. Cells take on the age-phenotype the body gives them.

Aging is not a defect – it’s a programmed progressive process, a continuation of development with the body doing more to kill itself with advancing years. Progressive life-states where each succeeding life-stage has a higher mortality (there are rare exceptions).

Cellular aging is externally controlled (cell non-autonomous). None of those remedies that slow ‘cell aging’ (basically all anti-aging medicines) can significantly extend anything but old age.

For change at the epigenomic/cellular level to travel up the biological hierarchy from cells to organ systems seems to take time. But the process can be repeated indefinitely (so far as we know).”

We may express concern about others. But each of us should also take responsibility for our own one precious life.

Gut microbiota and aging

This 2020 review explored the title subject:

“The human body contains 1013 human cells and 1014 commensal microbiota. Gut microbiota play vital roles in human development, physiology, immunity, and nutrition.

Human lifespan was thought to be determined by the combined influence of genetic, epigenetic, and environmental factors including lifestyle-associated factors such as exercise or diet. The role of symbiotic microorganisms has been ignored.

Age-associated alterations in composition, diversity, and functional features of gut microbiota are closely correlated with an age-related decline in immune system functioning (immunosenescence) and low-grade chronic inflammation (inflammaging). Immunosenescence and inflammaging do not have a unidirectional relationship. They exist in a mutually maintained state where immunosenescence is induced by inflammaging and vice versa.

Immunosenescence changes result in both quantitative and qualitative modifications of specific cellular subpopulations such as T cells, macrophages and natural killer cells as opposed to a global deterioration of the immune system. Neutrophils and macrophages from aged hosts are less active with diminished phagocytosing capability.

Gut microbiota transform environmental signals and dietary molecules into signaling metabolites to communicate with different organs and tissues in the host, mediating inflammation. Gut microbiota modulations via dietary or probiotics are useful anti-inflammaging and immunosenescence interventions.

The presence of microbiomic clocks in the human body makes noninvasive, accurate lifespan prediction possible. Prior to occurrence of aging-related diseases [shown above], bidirectional interactions between the gut and extraenteric tissue will change.

Correction of accelerated aging-associated gut dysbiosis is beneficial, suggesting a link between aging and gut microbiota that provides a rationale for microbiota-targeted interventions against age-related diseases. However, it is still unclear whether gut microbiota alterations are the cause or consequence of aging, and when and how to modulate gut microbiota to have anti-aging effects remain to be determined.”

https://www.tandfonline.com/doi/abs/10.1080/10408398.2020.1867054 “Gut microbiota and aging” (not freely available; thanks to Dr. Zongxin Ling for providing a copy)


1. The “Stable phase” predecessor to this review’s subject deserved its own paper:

“After initial exposure and critical transitional windows within 3 years after birth, it is generally agreed that human gut microbiota develops into the typical adult structure and composition that is relatively stable in adults.

gut microbiota by age phenotype

However, the Human Microbiome Project revealed that various factors such as food modernization, vaccines, antibiotics, and taking extreme hygiene measures will reduce human exposure to microbial symbionts and led to shrinkage of the core microbiome, while the reduction in microbiome biodiversity can compromise the human immune system and predispose individuals to several modern diseases.”

2. I looked for the ten germ-free references in the “How germ-free animals help elucidate the mechanisms” section of The gut microbiome: its role in brain health in this review, but didn’t find them cited. Likewise, the five germ-free references in this review weren’t cited in that paper. Good to see a variety of relevant research.

There were a few overlapping research groups with this review’s “Gut-brain axis aging” section, although it covered only AD and PD research.

3. Inflammaging is well-documented, but is chronic inflammation a condition of chronological age?

A twenty-something today who ate highly-processed food all their life could have gut microbiota roughly equivalent to their great-great grandparents’ at advanced ages. Except their ancestors’ conditions may have been byproducts of “an unintended consequence of both developmental programmes and maintenance programmes.

Would gut microbiota be a measure of such a twenty-something’s biological age? Do we wait until they’re 60, and explain their conditions by demographics? What could they do to reset themself back to a chronological-age-appropriate phenotype?