Fructose and survival

This 2023 paper provided mechanistic evidence, evolutionary theory, and testable scenarios for fructose metabolism differences from other nutrients:

“The fructose survival hypothesis proposes that obesity and metabolic disorders may have developed from over-stimulation of an evolutionary-based biologic response (survival switch) that aims to protect animals in advance of crisis. The response is characterized by hunger, thirst, foraging, weight gain, fat accumulation, insulin resistance, systemic inflammation, and increased blood pressure.

Unlike other nutrients, fructose reduces the active energy (adenosine triphosphate) in the cell, while blocking its regeneration from fat stores. This is mediated by intracellular uric acid, mitochondrial oxidative stress, inhibition of AMP kinase, and stimulation of vasopressin.

rstb20220230f04

Fructose metabolism is associated with oxidative stress, mitochondrial dysfunction, loss of cytoprotective transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2), and a reduction in sirtuins that characterize the ageing process. Fructose also induces generation of advanced glycation end products much more effectively than glucose.

The fructose pathway is almost inevitably strongest in early disease states, for over time there is often fibrosis, inflammation, or mitochondrial loss that results in persistence of the disease process. The best time for intervention may turn out to be in early disease before conditions become less reversible.”

https://royalsocietypublishing.org/doi/10.1098/rstb.2022.0230 “The fructose survival hypothesis for obesity”


Time to exit fructose survival mode.

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Acetyl-L-carnitine dosing

Haven’t curated acetyl-L-carnitine papers recently. Here are three 2023 studies, beginning with a human case report:

“It is believed that 75% of the required amount of carnitine is taken from diet and the remaining 25% is synthesized in the body. Long-term use of a carnitine-free diet is thought to increase the risk of carnitine deficiency.

Dosage for long-term tube-fed patients with disorders of consciousness and convulsive seizures, such as in the present cases, is not specified. Instructions accompanying the medication list gastrointestinal symptoms such as nausea, vomiting, and diarrhea as side effects of L-carnitine. They indicate a maximum dosage of 3 g/day, and a maximum single dose of 1 g.

L-Carnitine is efficiently absorbed in the gastrointestinal tract when taken in small amounts, but when taken in large amounts, the transporter is saturated and bioavailability is only about 10%–20%. Although safety of oral L-carnitine administration is considered high because there is an upper limit to the amount that can be absorbed, clinicians should remain aware of side effects noted above.

To the best of our knowledge, this is the first report in which L-carnitine was administered to a patient with impaired consciousness after stroke with the result that symptoms improved. It is possible that carnitine deficiency is overlooked in some patients in rehabilitation wards, and measurement of ammonia may be useful in its detection. Because carnitine deficiency might interfere with active rehabilitation, nutritional management with attention to carnitine deficiency is important in rehabilitation wards.”

https://www.jstage.jst.go.jp/article/prm/8/0/8_20230019/_html/-char/en “Disorders of Consciousness after Subacute Stroke Might Partly be Caused by Carnitine Deficiency: Two Case Reports”

I currently take one gram of acetyl-L-carnitine three times a day.


Next is a clinical trial with amyotrophic lateral sclerosis (ALS) patients that used two different doses of acetyl-L-carnitine:

“Our findings did not confirm an effect of ALCAR 3 g/day on survival in ALS subjects at 24 months. An effect was observed in those treated with ALCAR 1.5 g/day.

In addition, we did not detect an effect on self-sufficiency at 12 months as previously seen in the pilot trial. These differences could be explained by:

  • The study design (retrospective observational study vs prospective randomized trial);
  • Selection bias (subjects from the real-world clinical practice are less selected than those included in a clinical trial); and
  • Drug compliance (subjects enrolled in a clinical trial perform several onsite evaluations in which compliance is verified by tablets accounting, while in clinical practice this is not done).

Our hypothesis is that the presence of residual confounding might explain our unexpected results. Residual confounding refers to the presence of an unmeasured or uncontrolled variable that could affect the relationship between treatment (ALCAR) and outcome.

This study provided additional information on the potential effect of ALCAR on disease progression and survival, and adds evidence to justify the use of ALCAR in ALS subjects.”

https://link.springer.com/article/10.1007/s00415-023-11844-6 “Retrospective observational study on the use of acetyl-L-carnitine in ALS”

This study’s dosing method wasn’t clear on exactly how doses were administered every day. I’ll guess that if both 1.5 and 3 grams were given all at once, they might have been roughly equivalent doses per the first paper’s cited bioavailability saturation effect.


Next is a rodent aging study:

“The aim of this study was to examine effects of long-term L-Carnitine (β-hydroxy-γ-trimethylaminobutyric acid, LC) administration on cardiomyocyte contraction and intracellular Ca2+ transients in aging rats. LC (50 mg/kg body weight/day) was dissolved in distilled water and orally administered for a period of 7 months.

LC increased cardiomyocyte cell shortening and resting sarcomere length. LC supplementation led to a reduction in resting [Ca2+]i level and an increase in the amplitude of [Ca2+]i transients, indicative of enhanced contraction. Consistent with these results, decay time of Ca2+ transients also decreased significantly in the LC-treated group.

Long-term administration of LC may help restore Ca2+ homeostasis altered during aging, and could be used as a cardioprotective medication in cases where myocyte contractility is diminished.”

https://link.springer.com/article/10.1007/s00418-023-02215-3 “L-Carnitine improves mechanical responses of cardiomyocytes and restores Ca2+ homeostasis during aging” (not freely available)

A human equivalent of this study’s daily dose is (50 mg x .162) x 70 kg = 567 mg. A human equivalent of this study’s duration using the maximum lifespan method is (7 months x 32.2) = 225.4 months. The subjects began at 11 months old (human equivalent age 29.5 years) and ended at 18 months old (human equivalent age 48.3 years).

This study illustrated how heart dysfunctions with subclinical symptoms advance with aging, and that starting to do something preventative before human equivalent age 30 may work.


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Take Vitamin K2 to protect against aluminum toxicity

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

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.”

36 holes in your roof

An August 2023 interview with Dr. Dale Bredesen, who has reversed Alheizmer’s disease in many people, which will never be acknowledged by the corrupt paradigm:

“How much do you want me to go into things that are relatively controversial and how much do you want me to stick with kind of the more standard line?

For Alzheimer’s we noticed initially there are 36 different potential contributors. You need to patch as many as possible to have an effect.

All of these things, your estradiol level, your progesterone level, pregnenolone, free T3, TSH, Vitamin D, testosterone, these things are all critical. They all feed into the equation.

You have over a hundred trillion contacts in your brain. Will you be able to keep them? Or do you not have what it takes to keep them, and you have to downsize?

The reality is Alzheimer’s disease should be a rare disease. If everybody would get on appropriate prevention or early reversal, we could make it a rare disease.”

https://brokenscience.org/podcasts-ep-5/ “Dale Bredesen – Reversing Alzheimer’s Fate”


See A therapy to reverse cognitive decline for previous curation of Dr. Bredesen’s work.

The era of following wise old men ended a long time ago

I try to stay away from papers that waste resources or detract from science. This 2023 lab study irked me by emphasizing risks of home sprouting without also pointing out the many benefits.

These researchers, who obviously don’t home sprout, used the supplier I get organic broccoli seeds from as a punching bag. They consulted a broccoli sprouts expert to recommend bleaching seeds before sprouting.

Fine. Do these people ever eat a salad without also bleaching those ingredients? Do they risk eating at restaurants? How do they get motivated to take the risk of leaving their dwelling/dormitory?

What did our ancestors eat? Was it luck that they didn’t exterminate themselves with their food hygiene? Or have humans adapted to dealing with all types of pathogens?

The expert is a few weeks older than I am, and has completely white hair. I’ve had dark hair since Week 8 of eating broccoli sprouts every day, which reflects ameliorating system-wide inflammation and oxidative stress. Next month will be three and a half years of this daily practice.

If the expert followed what their research investigated, they’d have dark hair, too. White hair and dark hair are both epigenetic. It’s every human’s choice whether or not we take responsibility for our own one precious life.

https://www.mdpi.com/2304-8158/12/4/747 “Seed Disinfestation Practices to Control Seed-Borne Fungi and Bacteria in Home Production of Sprouts”


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Neuritogenesis

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”

Adverse Childhood Experiences, Part 2

A request was made to present studies that investigated epigenetic impacts of corporal punishments or physical trauma to children or adolescents. Here’s a follow-on of the 2015 Grokking an Adverse Childhood Experiences (ACE) score, since physical abuse is one factor of an ACE score.

1. The largest problem is that a person filling out an ACE questionnaire or Childhood Trauma Questionnaire can’t provide first-hand answers of their own experiences during womb life, infancy, and early childhood. These critical development periods are more impacted by adversity than are later life windows.

Human brains aren’t developed enough before age 3 to provide retrospective answers using cerebral memories. A self-reported ACE score can’t possibly address what happened during the times when we were most vulnerable to disrupted neurodevelopment. And good luck with parents providing factual histories of whether they physically or emotionally neglected, physically or emotionally abused, or otherwise adversely treated their fetus, infant, and young child.

2. Another problem is researchers can pretty much choose whatever questions they want as input criteria. I’ve seen pliable ACE scores developed from 5- to 25-item questionnaires.

Do these questionnaires cover all relevant adverse childhood experiences? For example, are researchers permitted to use as inputs societal-created adversities a child may have lived through such as the Khmer Rouge or Cultural Revolution? Studies are just starting to investigate adverse childhood experiences created by worldwide abuses of authority since 2020.

3. Other problems were discussed in a 2023 paper https://www.sciencedirect.com/science/article/abs/pii/S0145213423003162 “Adverse childhood experiences and adult outcomes using a causal framework perspective: Challenges and opportunities” (not freely available), two of which were:

  • Adding up ACE factors to a cumulative score ignores the impact of synergistic sets. For example, although both cumulative ACE scores are 2, a child who was physically and sexually abused would probably be more adversely affected than a child whose parents divorced or separated, and also had a family member incarcerated.
  • At any given time point, and especially with older people, there’s a potential selection bias against those most affected by adverse childhood experiences, such as those who died.

Using flawed, squishy, cumulative ACE scores as inputs, here are two 2023 studies that found epigenetic associations:

“We tested the following pre-registered hypotheses: Mothers’ adverse childhood experiences are correlated with DNA methylation (DNAm) in peripheral blood during pregnancy (hypothesis 1) and in cord blood samples from newborn infants (hypothesis 2), and women’s depression and anxiety symptoms during pregnancy mediate the association between mothers’ ACE exposure and prenatal/neonatal DNA methylation (hypothesis 3).

  1. Hypothesis 1: In 896 mother−infant pairs with available methylation and ACE exposure data, there were no significant associations between mothers’ ACE score and DNAm from antenatal peripheral blood, after controlling for covariates.
  2. Hypothesis 2: In infant cord blood, there were 5 CpG sites significantly differentially methylated in relation to mothers’ ACEs (false discovery rate < .05), but only in male offspring. Effect sizes were medium. CpG sites were in genes related to mitochondrial function and neuronal development in the cerebellum.
  3. Hypothesis 3: There was no mediation by maternal anxiety/depression symptoms found between mothers’ ACEs score and DNAm in the significant CpG sites in male cord blood.”

https://www.jaacap.org/article/S0890-8567(23)00313-1/fulltext “Epigenetic Intergenerational Transmission: Mothers’ Adverse Childhood Experiences and DNA Methylation”


“In this study, the effect of cumulative ACEs experienced on human maternal DNAm was estimated while accounting for interaction with domains of ACEs in prenatal peripheral blood mononuclear cell samples. Intergenerational transmission of ACE-associated DNAm was explored used paired maternal and neonatal cord blood samples. Replication in buccal samples was also explored.

We used a four-level categorical indicator variable for ACEs exposure: none (0 ACEs), low (1–3 ACEs), moderate (4–6 ACEs), and high (> 6 ACEs). 🙄

125a4c3cacfe4b922e5b864c

https://www.researchsquare.com/article/rs-2977515/v1 “Effect of Parental Adverse Childhood Experiences on Intergenerational DNA Methylation Signatures”

Natural ways to modify GDF11

Three 2023 studies to follow up mention of GDF11 in the Brain endothelial cells post. Two are selected for non-pharmaceutical interventions people can do on their own. Let’s start with a human exercise study:

“We explored the exercise-related regulation of Growth Differentiation Factor 11 (GDF11) in cerebrospinal fluid (CSF) and blood. Samples of serum, plasma, and CSF were obtained before and 60 min after acute exercise (90 min run) from twenty healthy young individuals. Additional serum and plasma samples were collected immediately after run. GDF11 protein content, body composition, physical fitness, and cognitive functions were evaluated.

Controversies regarding the role of GDF11 in aging originate mainly from the absence of a reliable, validated and widely accepted method of GDF11 detection. To support the reliability of our findings as well as to distinguish GDF11 from its close homologue GDF8, we determined GDF11 in CSF, serum, and plasma, by immunoblotting, using two different GDF11-specific antibodies, as well as GDF11/GDF8 non-specific antibody. These antibodies have been previously successfully used by others. Reliability of our findings is further supported by correlations between GDF11 in serum and plasma, as well as between GDF11 and serum GDF11/GDF8.

We report an association between levels of GDF11 and adiponectin in CSF as well as in serum after acute endurance exercise. These observations support potentially synergic effects of GDF11 and adiponectin on the brain. The experimental design we implement seems to represent a reliable model to study regulation of bioactive molecules, potential mediators of neuroprotective effects of exercise in the human brain.

We show for the first time a direct link between endurance exercise and GDF11 levels in human cerebrospinal fluid. This study provided the first albeit indirect (correlative) evidence on the putative role of GDF11 in promoting healthy aging in humans, by demonstrating a tight relationship between serum GDF11 and peak power output. We extend this observation by showing that the level of physical fitness is an important determinant of regulation of GDF11 by acute exercise.

In this work, we confirm in a bigger cohort our previous finding that blood-brain barrier permeability, as assessed by CSF/serum albumin ratio, is decreased after an acute bout of endurance exercise. We observed a modest positive correlation between CSF/serum albumin ratio and CSF/serum GDF11/GDF8 ratio, with a trend also for GDF11. However, exercise-induced changes of CSF/serum albumin ratio and that of GDF11 or GDF11/GDF8 did not correlate, indicating that there are other factors that could modulate levels of this growth factor rather than blood-brain barrier permeability.”

https://www.frontiersin.org/articles/10.3389/fendo.2023.1137048/full “Acute endurance exercise modulates growth differentiation factor 11 in cerebrospinal fluid of healthy young adults”


Next is a rodent study of intermittent fasting before and after cerebral ischemia:

“The present study focused on the cerebral angiogenesis effect of intermittent fasting (IF) on ischemic rats. Rats were fed within strict time periods for 8 h out of every 24 h, with free access to food between 0800 and 1600 h.

In the first step, we designed different time schedules (10 d, 1 month, and 3 months) of IF before middle cerebral artery occlusion (MCAO). We monitored whether IF accelerated neurobehavioral recovery and induced expression of endothelial cells after MCAO. Then we explored whether GDF11 and downstream signals mediated angiogenesis in the peri-infarct area.

journal.pone.0282338.g006

We found that 3 months (p < 0.01) and 1 month (p < 0.05) of IF conditioning, respectively, markedly increased GDF11-positive cells in the peri-infarct area 3 d after MCAO compared with ad libitum dietary regimen. There were no significant differences between the cerebral ischemia (CI) + ad libitum group and the CI + IF 10-day group.

We also assayed plasma expression pattern of GDF11 protein. Plasma level of GDF11 protein was significantly upregulated in the IF dietary groups compared with the ad libitum dietary group 3 d after MCAO, which was consistent with the brain level. However, short-term CI + IF 10-day group results were not statistically different from CI + ad libitum group.

Taken together, our results strongly indicated that pretreatment of long-term IF might promote circulation of GDF11 and cerebral GDF11 protein during the post-ischemic, recovery period. Preoperative long-term IF might be beneficial for inducing cerebral angiogenesis in acute cerebral infarction.

These findings suggested that the longer the period of IF before MCAO, the better the protective effects after surgery.”

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0282338 “Long-term intermittent fasting improves neurological function by promoting angiogenesis after cerebral ischemia via growth differentiation factor 11 signaling activation”

Per Week 28 of Changing to a youthful phenotype with broccoli sprouts, using species maximum lifespan to estimate a human-equivalent multiplication factor that can be applied to a rat post-development time period is 122.5 years / 3.8 years = 32.2. Applying it to this study’s findings:

  • 10 rat days (322 human days) of intermittent fasting provided little protection from cerebral ischemia;
  • 1 rat month (32.2 human months) of intermittent fasting had better protection; and
  • 3 rat months (a little over 8 human years) of intermittent fasting had even stronger protection.

Is it worth the hassle of intermittently fasting every day for years to prevent a future stroke, or better recover from one, or keep other subclinical / clinical diseases from accelerating, or keep aging from accelerating? This study also cited more immediate benefits of intermittent fasting.


Might be too late for a gradual approach for people who are already diseased or close, though, like subjects in this human study:

“We aimed to explore the correlation among serum GDF11, the severity of coronary artery lesions, and the prognosis of patients with ST-segment elevation myocardial infarction (STEMI). A total of 367 patients were enrolled and divided into control (n = 172) and STEMI (n = 195) groups. Control group fulfilled the following criteria:

  1. Presented with typical chest tightness, chest pain, or other discomfort symptoms on admission;
  2. Electrocardiogram examination suggested ST-T changes;
  3. Levels of myocardial injury markers did not suggest abnormalities; and
  4. The diagnosis of unstable angina was considered clinically valid.

14 variables that were significant in univariate logistic regression analysis were included in the subsequent multivariate logistic regression analysis. Multivariate analysis indicated that smoking, diabetes, C-reactive protein, homocysteine, and lipoprotein (a) were positively correlated with STEMI occurrence, whereas serum GDF11 and the Apolipoprotein A1-to-Apolipoprotein B ratio were negatively correlated with STEMI occurrence.

Serum GDF11 was negatively correlated with severity of coronary lesions, and was also an independent prognostic indicator of major adverse cardiovascular events in patients with STEMI.”

https://link.springer.com/article/10.1007/s12265-023-10358-w “Correlation Between GDF11 Serum Levels, Severity of Coronary Artery Lesions, and the Prognosis of Patients with ST-segment Elevation Myocardial Infarction” (not freely available)

Brain endothelial cells

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”

Taurine’s effects on healthspan and lifespan

A 2023 human / primate / rodent / worm study with 56 coauthors exhaustively investigated taurine effects:

“We measured the blood concentration of taurine during aging and investigated the effect of taurine supplementation on healthspan and lifespan in several species.

  • In C57Bl/6J wild-type (WT) mice, serum taurine concentrations declined from 132.3 ± 14.2 ng/ml at 4 weeks to 40.2 ± 7.1 ng/ml at 56 weeks.
  • In 15-year-old monkeys, serum taurine concentrations were 85% lower than in 5-year-old monkeys.
  • Taurine concentrations in elderly humans were decreased by more than 80% compared with concentration in serum of younger individuals.

Regardless of their sex, taurine-fed mice survived longer than control mice. The median lifespan increase was 10 to 12%, and life expectancy at 28 months increased by 18 to 25%.

Improved survival of taurine-fed mice was not a consequence of low survival of control animals or differences in diet. Taurine deficiency is a driver of aging in mice because its reversal increases lifespan.

lifespan extension starting taurine in middle age

We investigated the health of taurine-fed middle-aged mice and found an improved functioning of bone, muscle, pancreas, brain, fat, gut, and immune system, indicating an overall increase in healthspan. Taurine reduced cellular senescence, protected against telomerase deficiency, suppressed mitochondrial dysfunction, decreased DNA damage, and attenuated inflammation.

An association analysis of metabolite clinical risk factors in humans showed that lower taurine, hypotaurine, and N-acetyltaurine concentrations were associated with adverse health, such as increased abdominal obesity, hypertension, inflammation, and prevalence of type 2 diabetes. We found that a bout of exercise increased concentrations of taurine metabolites in blood, which might partially underlie antiaging effects of exercise.

Taurine abundance decreases during aging. A reversal of this decline through taurine supplementation increases healthspan and lifespan in mice and worms, and healthspan in monkeys.”

https://www.science.org/doi/10.1126/science.abn9257 “Taurine deficiency as a driver of aging”


One area curiously not investigated in this study was that taurine supplementation freed up cysteine to do things other than synthesize taurine, like synthesize glutathione, an idea in Treating psychopathological symptoms will somehow resolve causes? An introductory article brought up this point:

“One of the most studied mechanisms of action for taurine is an increase in antioxidant capacity. Although oxidative damage is not clearly linked to mammalian lifespan, it plays a role in many age-associated pathologies.

Taurine is a poor scavenger of reactive oxygen species, with the exception of hypochlorite, which it detoxifies to N-chlorotaurine. N-Chlorotaurine is anti-inflammatory and induces expression of antioxidant enzymes in mice and humans.

Taurine supplementation might also cause an increase in levels of its precursors, including the antioxidants hypotaurine and cysteine. An interesting corollary is that up-regulating endogenous taurine synthesis would have the opposite result—consuming hypotaurine and cysteine.”

https://www.science.org/doi/10.1126/science.adi3025 “Taurine linked with healthy aging”


A human equivalent taurine dose is (1 g x .081) x 70 kg = 5.67 grams. Dose tests from supplementary data were:

“Dose and frequency of taurine administration was selected based on a pilot study, which showed that when given once daily to middle-aged WT mice, this regimen increased peak blood taurine concentrations to baseline concentrations in young (4-week-old) mice.”

taurine dose

I’ve taken 2 grams every day for the past three years, and will now bump that up to 5 grams. My diet doesn’t regularly include any foods high in taurine.

I recommend reading the study rather than commentaries. Its publisher did a very good job of linking figures so that images can be viewed, then the reader returned to the right context.

Gatekeepers are out in full force on this study, and their viewpoints are probably what you’ll see first, to include unevidenced statements like “the study’s main authors cautioned the public not to self-dose with the supplement” and the above introductory article’s unreferenced “equivalent doses used in the study by Singh et al. would be very high in humans.” Pretty pathetic that such ‘authorities’ are even publicized after recent years of deliberately misleading the world about science and medicine.

This study and all commentaries called for clinical trials that are NOT going to happen:

  • Drug companies can’t make money from a research area that’s cheap, not patentable, and readily accessible.
  • Government sponsors are likewise not incentivized to act in the public’s interest per their recent behavior.

Take responsibility for your own one precious life. See Part 2 for a sample of citing papers.

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Nrf2 Week #6: Phytochemicals

This 2023 review explored Nrf2 relationships with plant chemicals:

“This review focuses on possible mechanisms of Nrf2 activation by natural phytochemicals in preventing or treating chronic diseases, and regulating oxidative stress. Excess oxidative stress is closely related to many kinds of chronic diseases, such as cardiovascular diseases, cancer, neurodegenerative diseases, diabetes, obesity, and other inflammatory diseases.

Mitochondrial dysfunction and hyperglycemia lead to the massive production of ROS, which triggers molecular damage, inflammation, ferroptosis, insulin resistance, and β-cell dysfunction.

antioxidants-12-00236-g001

Crosstalk between Keap1-Nrf2-ARE pathway and other signaling pathways endows it with high complexity and significance in the multi-function of phytochemicals. Limited human data makes an urgent need to open the new field of phytochemical-original supplement application in human chronic disease prevention.”

https://www.mdpi.com/2076-3921/12/2/236 “The Regulatory Effect of Phytochemicals on Chronic Diseases by Targeting Nrf2-ARE Signaling Pathway”


Top ten mentions, not including references:

  • 21 Sulforaphane
  • 16 Broccoli
  • 9 Curcumin
  • 5 Resveratrol
  • 5 Green tea catechins
  • 4 Luteolin
  • 3 Garlic
  • 3 Soy isoflavones
  • 3 Lycopene
  • 3 Quercetin

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Nrf2 Week #3: Epigenetics

To follow the Nrf2 Week #2 finding that chromatin accessibility parallels Nrf2 expression, this 2023 cell study explored how Nrf2 influences other epigenetic processes:

“We identified antioxidant response element sequences in promoter regions of genes encoding several epigenetic regulatory factors, such as histone deacetylases (HDACs), DNA methyltransferases (DNMTs), and proteins involved in microRNA biogenesis.

  • We treated cells with dimethyl fumarate (DMF), an activator of the NRF2 pathway through both the KEAP1 and GSK-3 pathways. NRF2 is able to modulate expression of HDAC1, HDAC2, HDAC3, and SIRT1 in different cell types.
  • DMF treatment induced DNMT1 and DNMT3b at both mRNA and protein levels. For DNMT3a, there was a slight induction of mRNA levels but not at the protein level.

antioxidants-12-00641-g007

  • Our data indicate that of all miRNAs analyzed, only miR-27a-3p, miR-27b-3p, miR-128-3p, and miR-155-5p associate with Nfe2l2 mRNA. NRF2 causes degradation of miR-155-5p, which is implicated in neuroinflammation and other pathologies, and is the main miRNA induced by LPS treatment in microglia. miR-155 alters expression of genes that regulate axon growth, supporting the bioinformatic prediction that miR-155 can regulate expression of genes involved in central nervous system development and neurogenesis.

Todate we only understand how epigenetic modifications affect expression and function of the NRF2 pathway. The fact that NRF2 can promote expression of type I HDACs, DNMTs, and proteins involved in miRNA biogenesis opens new perspectives on the spectrum of actions of NRF2 and its epigenetic influences.”

https://www.mdpi.com/2076-3921/12/3/641 “The Transcription Factor NRF2 Has Epigenetic Regulatory Functions Modulating HDACs, DNMTs, and miRNA Biogenesis”


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Nrf2 Week #2: Neurons

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”


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Eat broccoli sprouts for depression, Part 3

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”


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