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?


The future of your brain is in your gut right now

A 2020 paper by the author of Sulforaphane: Its “Coming of Age” as a Clinically Relevant Nutraceutical in the Prevention and Treatment of Chronic Disease:

“The gut and brain communicate bidirectionally via several pathways which include:

  1. Neural via the vagus nerve;
  2. Endocrine via the HPA axis;
  3. Neurotransmitters, some of which are synthesized by microbes;
  4. Immune via cytokines; and
  5. Metabolic via microbially generated short-chain fatty acids.

How does nature maintain the gut-microbiome-brain axis? Mechanisms to maintain homeostasis of intestinal epithelial cells and their underlying cells are a key consideration.

The symbiotic relationship that exists between microbiota and the human host is evident when considering nutrient requirements of each. The host provides food for microbes, which consume that food to produce metabolites necessary for health of the host.

Consider function of the human nervous system, not in isolation but in integration with the gastrointestinal ecosystem of the host, in expectation of a favorable impact on human health and behavior.”

https://www.sciencedirect.com/science/article/pii/B9780128205938000148 “Chapter 14 – The gut microbiome: its role in brain health” (not freely available)


Always more questions:

  • What did you put into your gut today?
  • What type of internal environment did it support?
  • What “favorable impact on human health and behavior” do you expect from today’s intake?
  • How will you feel?
  • Will you let evidence guide feeding your gut environment?

See Switch on your Nrf2 signaling pathway for an interview with the author.

How will you feel?

Consider this a partial repost of Moral Fiber:

“We are all self-reproducing bioreactors. We provide an environment for trillions of microbes, most of which cannot survive for long without the food, shelter and a place to breed that we provide.

They inhabit us so thoroughly that not a single tissue in our body is sterile. Our microbiome affects our development, character, mood and health, and we affect it via our diet, medications and mood states.

The microbiome:

  • Affects our thinking and our mood;
  • Influences how we develop;
  • Molds our personalities;
  • Our sociability;
  • Our responses to fear and pain;
  • Our proneness to brain disease; and
  • May be as or more important in these respects than our genetic makeup.

Dysbiosis has become prevalent due to removal of prebiotic fibers from today’s ultra-processed foods. I believe that dietary shift has created a generation of humans less able to sustain or receive love.

They suffer from reduced motivation and lower impulse control. They are more anxious, more depressed, more selfish, more polarized, and therefore more susceptible to the corrosive politics of identity.


Other recent blog posts by Dr. Paul Clayton and team include Skin in The Game and Kenosha Kids.

Image from Thomas Cole : The Consummation, The Course of the Empire (1836) Canvas Gallery Wrapped Giclee Wall Art Print (D4060)

A case for carnitine supplementation

This 2020 review subject was carnitine, acetyl-L-carnitine, and its other molecular forms:

“Carnitine is necessary to deliver long-chain fatty acids from cytosol into mitochondria. Carnitine homeostasis is maintained by diet and renal absorption, as only a small amount (about 25%) is obtained by endogenous biosynthesis.

Defective fatty acid oxidation occurs with reduced intracellular levels of carnitine, leading to glucose consumption instead of lipid consumption, resulting in hypoglycemia. Non-metabolized lipids accumulate in tissues such as heart, skeletal muscle, and liver, resulting in myopathy and hepatic steatosis.

2000 mg/day is unlikely to provoke unwanted side effects and is safe for humans. In-depth studies are needed to identify a unique method of analysis which can guarantee efficient monitoring of supplement active component amounts.”

https://www.mdpi.com/1420-3049/25/9/2127/htm “The Nutraceutical Value of Carnitine and Its Use in Dietary Supplements”


The review listed animal studies of L-carnitine alone and in combination with:

  • Vitamin D3;
  • Coenzyme Q10;
  • Nicotinamide riboside;
  • Selenium;
  • L-arginine;
  • Anti-histamine drugs cetirizine hydrochloride and chlorpheniramine maleate; and
  • Hypertension drug olmesartan.

Human studies of its effects included:

  • Muscle soreness, damage biomarkers, and cramps;
  • Osteoarthritis knee pain and inflammation markers;
  • Ischemic cerebrovascular injury;
  • Peripheral neuropathy;
  • Nonalcoholic fatty liver disease;
  • Insulin resistance and Type 2 diabetes;
  • Kidney diseases;
  • Inherited diseases phenylketonuria and maple syrup urine;
  • Stress, depression, and anxiety;
  • Male infertility; and
  • Hepatitis C.

A broccoli sprouts study that lacked evidence for human applicability

A 2020 study Combined Broccoli Sprouts and Green Tea Polyphenols Contribute to the Prevention of Estrogen Receptor–Negative Mammary Cancer via Cell Cycle Arrest and Inducing Apoptosis in HER2/neu Mice (not freely available) conclusion was:

“Lifelong BSp [broccoli sprouts] and GTP [green tea polyphenol] administration can prevent estrogen receptor–negative mammary tumorigenesis through cell cycle arrest and inducing apoptosis in HER2/neu mice.”

These researchers had unaddressed insufficiencies in this study that were also in their 2018 study as curated below. The largest item that required translation into human applicability was rodent diet content of 26% “broccoli sprout seeds.”

You may be surprised to read the below previous study’s unevidenced advice to eat double the weight of broccoli sprouts that I eat every day. You won’t be surprised that it’s not going to happen. Especially when no alternatives were presented because rodent diet details weren’t analyzed and published.

Sulforaphane is an evolved defense mechanism to ward off predators, and eating it is evolutionarily unpleasant. Will people in general and pregnant women in particular eat a diet equivalent to 26% “broccoli sprout seeds?”

Where were peer reviewer comments and researcher responses? Are these not public as they are by all Open Access journals hosted on https://www.mdpi.com/?

Sponsors and researchers become locked into paradigms that permit human-inapplicable animal research year after year. What keeps them from developing sufficient human-applicable evidence to support their hypotheses?


This 2018 Alabama rodent study investigated the epigenetic effects on developing breast cancer of timing a sulforaphane-based broccoli sprouts diet. Timing of the diet was as follows:

  1. Conception through weaning (postnatal day 28), named the Prenatal/maternal BSp (broccoli sprouts) treatment (what the mothers ate starting when they were adults at 12 weeks until their pups were weaned; the pups were never on a broccoli sprouts diet);
  2. Postnatal day 28 through the termination of the experiment, named the Postnatal early-life BSp treatment (what the offspring ate starting at 4 weeks; the mothers were never on a broccoli sprouts diet); and
  3. Postnatal day 56 through the termination of the experiment, named the Postnatal adult BSp treatment (what the offspring ate starting when they were adults at 8 weeks; the mothers were never on a broccoli sprouts diet).

“The experiment was terminated when the mean tumor diameter in the control mice exceeded 1.0 cm.

Our study indicates a prenatal/maternal BSp dietary treatment exhibited maximal preventive effects in inhibiting breast cancer development compared to postnatal early-life and adult BSp treatments in two transgenic mouse models that can develop breast cancer.

Postnatal early-life BSp treatment starting prior to puberty onset showed protective effects in prevention of breast cancer but was not as effective as the prenatal/maternal BSp treatment. However, adulthood-administered BSp diet did not reduce mammary tumorigenesis.

The prenatal/maternal BSp diet may:

  • Primarily influence histone modification processes rather than DNA methylation processes that may contribute to its early breast cancer prevention effects;
  • Exert its transplacental breast cancer chemoprevention effects through enhanced histone acetylation activator markers due to reduced HDAC1 expression and enzymatic activity.

This may be also due to the importance of a dietary intervention window that occurs during a critical oncogenic transition period, which is in early life for these two tested transgenic mouse models. Determination of a critical oncogenic transition period could be complicated in humans, which may partially explain the controversial findings of the adult BSp treatment on breast cancer development in the tested mouse models as compared the previous studies. Thus long-term consumption of BSp diet is recommended to prevent cancers in humans.”

“The dietary concentration for BSp used in the mouse studies was 26% BSp in formulated diet, which is equivalent to 266 g (~4 cups) BSp/per day for human consumption. The concentration of BSp in this diet is physiological available and represents a practical consumption level in the human diet.

Prior to the experiment, we tested the potential influences of this prenatal/maternal BSp regimen on maternal and offspring health as well as mammary gland development in the offspring. Our results showed there was no negative effect of this dietary regimen on the above mentioned factors (data not shown) suggesting this diet is safe to use during pregnancy.”


I didn’t see where the above-labelled “Broccoli Sprout Seeds” diet content was defined. It’s one thing to state:

“SFN as the most abundant and bioactive compound in the BSp diet has been identified as a potent HDAC inhibitor that preferably influences histone acetylation processes.”

and describe how sulforaphane may do this and may do that, and include it in the study’s title. It’s another thing to quantify an animal study into findings that can help humans.

The study’s food manufacturer offers dietary products to the public without quantifying all contents. Good for them if they can stay in business by serving customers who can’t be bothered with scientific evidence.

Any difference between the above-labelled “Broccoli Sprout Seeds” and broccoli seeds? Where was any evidence that “Broccoli Sprout Seeds” and SPROUTED “Broccoli Sprout Seeds” were equivalent per this claim:

“Equivalent to 266 g (~4 cups) BSp/per day for human consumption. The concentration of BSp in this diet is physiological available and represents a practical consumption level in the human diet.”

To help humans, this animal study had to have more details than the food manufacturer provided. These researchers should have either tasked the manufacturer to specify “Broccoli Sprout Seeds” content, or contracted out analysis if they weren’t going to do it themselves.

Regarding timing of a broccoli sprouts diet for humans, this study didn’t provide evidence for recommending:

“Long-term consumption of BSp diet is recommended to prevent cancers in humans.”

http://cancerpreventionresearch.aacrjournals.org/content/early/2018/05/15/1940-6207.CAPR-17-0423.full-text.pdf “Temporal efficacy of a sulforaphane-based broccoli sprout diet in prevention of breast cancer through modulation of epigenetic mechanisms”

Clearing out the 2020 queue of interesting papers

I’ve partially read these 39 studies and reviews, but haven’t taken time to curate them.

Early Life

  1. Intergenerational Transmission of Cortical Sulcal Patterns from Mothers to their Children (not freely available)
  2. Differences in DNA Methylation Reprogramming Underlie the Sexual Dimorphism of Behavioral Disorder Caused by Prenatal Stress in Rats
  3. Maternal Diabetes Induces Immune Dysfunction in Autistic Offspring Through Oxidative Stress in Hematopoietic Stem Cells
  4. Maternal prenatal depression and epigenetic age deceleration: testing potentially confounding effects of prenatal stress and SSRI use
  5. Maternal trauma and fear history predict BDNF methylation and gene expression in newborns
  6. Adverse childhood experiences, posttraumatic stress, and FKBP5 methylation patterns in postpartum women and their newborn infants (not freely available)
  7. Maternal choline supplementation during the third trimester of pregnancy improves infant information processing speed: a randomized, double‐blind, controlled feeding study
  8. Preterm birth is associated with epigenetic programming of transgenerational hypertension in mice
  9. Epigenetic mechanisms activated by childhood adversity (not freely available)

Epigenetic clocks

  1. GrimAge outperforms other epigenetic clocks in the prediction of age-related clinical phenotypes and all-cause mortality (not freely available)
  2. Epigenetic age is a cell‐intrinsic property in transplanted human hematopoietic cells
  3. An epigenetic clock for human skeletal muscle
  4. Immune epigenetic age in pregnancy and 1 year after birth: Associations with weight change (not freely available)
  5. Vasomotor Symptoms and Accelerated Epigenetic Aging in the Women’s Health Initiative (WHI) (not freely available)
  6. Estimating breast tissue-specific DNA methylation age using next-generation sequencing data

Epigenetics

  1. The Intersection of Epigenetics and Metabolism in Trained Immunity (not freely available)
  2. Leptin regulates exon-specific transcription of the Bdnf gene via epigenetic modifications mediated by an AKT/p300 HAT cascade
  3. Transcriptional Regulation of Inflammasomes
  4. Adipose-derived mesenchymal stem cells protect against CMS-induced depression-like behaviors in mice via regulating the Nrf2/HO-1 and TLR4/NF-κB signaling pathways
  5. Serotonin Modulates AhR Activation by Interfering with CYP1A1-Mediated Clearance of AhR Ligands
  6. Repeated stress exposure in mid-adolescence attenuates behavioral, noradrenergic, and epigenetic effects of trauma-like stress in early adult male rats
  7. Double-edged sword: The evolutionary consequences of the epigenetic silencing of transposable elements
  8. Blueprint of human thymopoiesis reveals molecular mechanisms of stage-specific TCR enhancer activation
  9. Statin Treatment-Induced Development of Type 2 Diabetes: From Clinical Evidence to Mechanistic Insights
  10. Rewiring of glucose metabolism defines trained immunity induced by oxidized low-density lipoprotein
  11. Chronic Mild Stress Modified Epigenetic Mechanisms Leading to Accelerated Senescence and Impaired Cognitive Performance in Mice
  12. FKBP5-associated miRNA signature as a putative biomarker for PTSD in recently traumatized individuals
  13. Metabolic and epigenetic regulation of T-cell exhaustion (not freely available)

Aging

  1. Molecular and cellular mechanisms of aging in hematopoietic stem cells and their niches
  2. Epigenetic regulation of bone remodeling by natural compounds
  3. Microglial Corpse Clearance: Lessons From Macrophages
  4. Plasma proteomic biomarker signature of age predicts health and life span
  5. Ancestral stress programs sex-specific biological aging trajectories and non-communicable disease risk

Broccoli sprouts

  1. Dietary Indole-3-Carbinol Alleviated Spleen Enlargement, Enhanced IgG Response in C3H/HeN Mice Infected with Citrobacter rodentium
  2. Effects of caffeic acid on epigenetics in the brain of rats with chronic unpredictable mild stress
  3. Effects of sulforaphane in the central nervous system
  4. Thiol antioxidant thioredoxin reductase: A prospective biochemical crossroads between anticancer and antiparasitic treatments of the modern era (not freely available)
  5. Quantification of dicarbonyl compounds in commonly consumed foods and drinks; presentation of a food composition database for dicarbonyls (not freely available)
  6. Sulforaphane Reverses the Amyloid-β Oligomers Induced Depressive-Like Behavior (not freely available)

Nano-sulforaphane vs. barbecue chemicals

This 2020 chicken study investigated the capability of nano-sulforaphane to protect embryonic survival and neurogenesis from a barbecued meat chemical:

“Common teratogenic [of, relating to, or causing malformations of an embryo or a fetus] factors related to the development of the nervous system, such as alcohol consumption and smoking, have attracted wide attention. Teratogenic factors such as PhIP, the most abundant amine produced in common cooking procedures, can affect early embryonic development, leading to abnormal development of the nervous system.

Nano-sized medicine, in comparison with conventional medicine, leads to increased active concentrations and bioavailability. Both PhIP and nanoparticles can cross the placental barrier and enter the fetus from the external environment.

Chick embryos (100 per group) were incubated with 0.1% DMSO (Control); 20μM, 100μM, 200μM, or 300μM PhIP; or 200μM PhIP + 5μM Nano-SFN [sulforaphane] for 36 h:

  • Mortality rates were 0% for the Control, 8% with 20μM PhIP, 20% with 100μM PhIP, 53% with 200μM PhIP, 85% with 300μM PhIP, and 7% with 200μM PhIP + 5μM Nano-SFN.
  • Neural tube malformation rates [for the remaining live embryos] were 0% for the Control, 5% with 20μM PhIP, 14% with 100μM PhIP, 36% with 200μM PhIP, 14% with 300μM PhIP, and 6% with 200μM PhIP + 5μM Nano-SFN.

Women at the early stage of pregnancy should avoid barbecue. Instead, increase intake amount of cruciferous vegetables, which benefits fetal neural development.”

https://www.sciencedirect.com/science/article/abs/pii/S0940960220301618 “Nano-sulforaphane attenuates PhIP-induced early abnormal embryonic neuro-development” (not freely available)


PXL_20201022_225011002.NIGHT

Eat broccoli sprouts to pivot your internal environment’s signals

Two 2020 reviews covered some aspects of a broccoli sprouts primary action – NRF2 signaling pathway activation:

“Full understanding of the properties of drug candidates rely partly on the identification, validation, and use of biomarkers to optimize clinical applications. This review focuses on results from clinical trials with four agents known to target NRF2 signaling in preclinical studies, and evaluates the successes and limitations of biomarkers focused on:

  • Expression of NRF2 target genes [AKR1, GCL, GST, HMOX1, NQO1] and others [HDAC, HSP];
  • Inflammation [COX-2, CRP, IL-1β, IL-6, IP-10, MCP-1, MIG, NF-κB, TNF-α] and oxidative stress [8-OHdG, Cys/CySS, GSH/GSSG] biomarkers;
  • Carcinogen metabolism and adduct biomarkers in unavoidably exposed populations; and
  • Targeted and untargeted metabolomics [HDL, LDL, TG].

No biomarkers excel at defining pharmacodynamic actions in this setting.

SFN [sulforaphane] seems to affect multiple downstream pathways associated with anti-inflammatory actions. NRF2 signaling may be but one pivotal pathway.

SFN is generally considered to be the most potent natural product inducer of Nrf2 signaling. Studies in which these actions are diminished or abrogated in parallel experiments in Nrf2-disrupted mice provide the strongest lines of evidence for a key role of this transcription factor in its actions.

It is equally evident that other modes of action contribute to the molecular responses to SFN in animals and humans. Such polypharmacy may well contribute to the efficacy of the agent in disease prevention and mitigation, but obfuscates the value of specific pharmacodynamic biomarkers in the clinical development and evaluation of SFN.”

https://www.mdpi.com/2076-3921/9/8/716/htm “Current Landscape of NRF2 Biomarkers in Clinical Trials”


Why do researchers still not use epigenetic clocks in sulforaphane clinical trials? Forty mentions of disease in this review, but no consideration of aging?

This was another example of how researchers – even when stuck in a paradigm they know doesn’t sufficiently explain their area (“No biomarkers excel”) – don’t investigate other associated research areas. Why not?

Here’s what Part 2 of Rejuvenation therapy and sulforaphane had to say to those stuck on biomarkers:

“While clinical biomarkers have obvious advantages (being indicative of organ dysfunction or disease), they are neither sufficiently mechanistic nor proximal to fundamental mechanisms of aging to serve as indicators of them. It has long been recognized that epigenetic changes are one of several primary hallmarks of aging.

DNA methylation epigenetic clocks capture aspects of biological age.”


The second review Epigenetic Regulation of NRF2/KEAP1 by Phytochemicals also completely whiffed on epigenetic clocks. One mention of aging in this review, but it wasn’t of:

  • Citation 104 from Archives of Gerontology and Geriatrics; nor of
  • Citation 108 from the March 31, 2020, Aging journal; nor of
  • Citation 131 “Dietary epigenetics in cancer and aging.”

But epigenetic clock and aging associations were certainly in this review’s scope. For example, Citation 119 said:

“Nrf2 transcriptional activity declines with age, leading to age-related GSH loss among other losses associated with Nrf2-activated genes. This effect has implications, too, for decline in vascular function with age. Some of the age-related decline in function can be restored with Nrf2 activation by SFN.”

Why would people bother with phytochemicals (buzzword “compounds produced by plants”) unless to either ameliorate symptoms or address causes?

“Epigenetic Regulation of NRF2/KEAP1 by Phytochemicals” doesn’t occur in just laboratory situations. It’s also part of daily life.

These reviewers were straight-forward with side effects for two of the first review’s four items:

“The best known NRF2 activator that has obtained clinical approval is dimethyl fumarate for the treatment of multiple sclerosis. However, it has several side effects, including allergic reactions and gastrointestinal disturbance. There are a few related agents in clinical trials, such as Bardoxolone and SFX-01, a synthetic derivative of sulforaphane, which also exhibit less than desirable outcomes.”


Treating psychopathological symptoms will somehow resolve causes?

This 2020 Swiss review subject was potential glutathione therapies for stress:

“We examine the available data supporting a role for GSH levels and antioxidant function in the brain in relation to anxiety and stress-related psychopathologies. Several promising compounds could raise GSH levels in the brain by either increasing the availability of its precursors or the expression of GSH-regulating enzymes through activation of Nrf2.

GSH is the main cellular antioxidant found in all mammalian tissues. In the brain, GSH homeostasis has an additional level of complexity in that the expression of GSH and GSH-related enzymes are not evenly distributed across all cell types, requiring the coordination between neurons and astrocytes to neutralize oxidative insults.

Increased energy demand in situations of chronic stress leads to mitochondrial ROS overproduction, oxidative damage and exhaustion of GSH pools in the brain.

Several compounds can function as precursors of GSH by acting as cysteine (Cys) donors such as taurine or glutamate (Glu) donors such as glutamine (Gln). Other compounds stimulate the synthesis and recycling of GSH through the activation of the Nrf2 pathway including sulforaphane and melatonin. Compounds such as acetyl-L-carnitine can increase GSH levels.”

https://www.sciencedirect.com/science/article/abs/pii/S0149763419311133 “Therapeutic potential of glutathione-enhancers in stress-related psychopathologies” (not freely available)


Many animal studies of “stress-related psychopathologies” were cited without noting applicability to humans. The reviewers instead had curious none-of-this-means-anything disclaimers like:

“Comparisons between studies investigating brain disorders of such different nature such as psychiatric disorders or neurodegenerative diseases, or even between brain or non-brain related disorders should be made with caution.”

Regardless, this paper had informative sections for my 27th week of eating broccoli sprouts every day.

1. I forgot to mention in Broccoli sprout synergies that I’ve taken 500 mg of trimethyl glycine (aka betaine) twice a day for over 15 years. Section 3.1.2 highlighted the amino acid glycine:

“Endogenous synthesis is insufficient to meet metabolic demands for most mammals (including humans) and additional glycine must be obtained from the diet. While most research has focused on increasing cysteine levels in the brain in order to drive GSH synthesis, glycine supplementation alone or in combination with cysteine-enhancing compounds are gaining attention for their ability to enhance GSH.”

2. The amino acid taurine dropped off my supplement regimen last year after taking 500 mg twice a day for years. It’s back on now after reading Section 3.1.3:

“Most studies that reported enhanced GSH in the brain following taurine treatment were performed under a chronic regimen and used in age-related disease models. Such positive effects of taurine on GSH levels may be explained by the fact that cysteine is the essential precursor to both metabolites, whereby taurine supplementation may drive the metabolism of cysteine towards GSH synthesis.

3. A study in Upgrade your brain’s switchboard with broccoli sprouts was cited for its potential:

“Thalamic GSH values significantly correlated with blood GSH levels, suggesting that peripheral GSH levels may be a marker of brain GSH content. Studies point to the capacity of sulforaphane to function both as a prophylactic against stress-induced behavioral changes and as a positive modulator in healthy animals.”


Sunrise minus 5 minutes

Unraveling oxytocin – is it nature’s medicine?

This 2020 review attempted to consolidate thousands of research papers on oxytocin:

“Chemical properties of oxytocin make this molecule difficult to work with and to measure. Effects of oxytocin are context-dependent, sexually dimorphic, and altered by experience. Its relationship to a related hormone, vasopressin, have created challenges for its use as a therapeutic drug.

Widely used medical interventions i.e.:

  • Exogenous oxytocin, such as Pitocin given to facilitate labor;
  • Opioid medications that block the oxytocin system; or
  • Cesarean sections that alter exposure to endogenous oxytocin

have lasting consequences for the offspring and/or mother.

Such exposures hold the potential to have epigenetic effects on the oxytocin systems, including changes in DNA methylation. These changes in turn would have lasting effects on the expression of receptors for oxytocin, leaving individuals differentially able to respond to oxytocin and also possibly to the effects of vasopressin.

Regions with especially high levels of OXTR [oxytocin receptor gene] are:

  • Various parts of the amygdala;
  • Bed nucleus of the stria terminalis;
  • Nucleus accumbens;
  • Brainstem source nuclei for the autonomic nervous system;
  • Systems that regulate the HPA axis; as well as
  • Brainstem tissues involved in pain and social attention.

Oxytocin protects neural cells against hypoxic-ischemic conditions by:

  • Preserving mitochondrial function;
  • Reducing oxidative stress; and
  • Decreasing a chromatin protein that is released during inflammation

which can activate microglia through the receptor for advanced glycation end products (RAGE). RAGE acts as an oxytocin-binding protein facilitating the transport of oxytocin across the blood-brain barrier and through other tissues.

Directionality of this transport is 5–10 times higher from the blood to the brain, in comparison with brain to blood transport. Individual differences in RAGE could help to predict cellular access to oxytocin and might also facilitate access to oxytocin under conditions of stress or illness.

Oxytocin and vasopressin and their receptors are genetically variable, epigenetically regulated, and sensitive to stressors and diet across the lifespan. As one example, salt releases vasopressin and also oxytocin.

Nicotine is a potent regulator of vasopressin. Smoking, including prenatal exposure of a fetus, holds the potential to adjust this system with effects that likely differ between males and females and that may be transgenerational.

Relative concentrations of endogenous oxytocin and vasopressin in plasma were associated with:

These studies support the usefulness of measurements of both oxytocin and vasopressin but leave many empirical questions unresolved.

The vast majority of oxytocin in biosamples evades detection using conventional approaches to measurement.”

https://pharmrev.aspetjournals.org/content/pharmrev/72/4/829.full.pdf “Is Oxytocin Nature’s Medicine?”


I appreciated efforts to extract worthwhile oxytocin research from countless poorly performed studies, research that wasted resources, and research that actually detracted from science.

I was disappointed that at least one of the reviewers didn’t take this review as an opportunity to confess their previous wastes like three flimsy studies discussed in Using oxytocin receptor gene methylation to pursue an agenda.

Frank interpretations of one’s own study findings to acknowledge limitations is one way researchers can address items upfront that will be questioned anyway. Such analyses also indicate a goal to advance science.

Although these reviewers didn’t provide concrete answers to many questions, they highlighted promising research areas, such as:

  • Improved approaches to oxytocin measurements;
  • Prenatal epigenetic experience associations with oxytocin and OXTR; and
  • Possible transgenerational transmission of these prenatal epigenetic experiences.

Take responsibility for your one precious life – DHEA

This 2020 meta-analysis subject was DHEA:

“Twenty-four qualified trials were included in this meta-analysis. Statistically significant increases in serum IGF-1 levels were found only in participants who were:

  1. Women; or
  2. Supplementing 50 mg/d; or
  3. Undergoing intervention for > 12 weeks; or
  4. Without an underlying comorbidity; or
  5. Over the age of 60 years.

DHEA supplementation led to an overall increase of ~16 ng/ml in serum IGF-1 levels, as well as increases of ~23 [women] and ~20 ng/ml [age > 60]. Diseased and healthy subjects ages ranged from 20 to 72 years old.”

Discussion section explanations of the above:

  1. “Women are more susceptible to biochemical and clinical shifts caused by DHEA supplementation.
  2. The majority of investigations tested DHEA at a dose of 50 mg/d.
  3. The majority of studies were performed for > 12 weeks.
  4. Participants with no comorbidities were also older in many studies.
  5. Older patients have a natural decline in the production of IGF-1 and DHEA.

Additional rigorous RCTs are warranted to better define whether and to what extent changes in IGF-1 levels caused by DHEA supplementation are relevant for health benefits.”

https://www.sciencedirect.com/science/article/abs/pii/S0531556520302977Impact of dehydroepian[d]rosterone (DHEA) supplementation on serum levels of insulin-like growth factor 1 (IGF-1): A dose-response meta-analysis of randomized controlled trials” (not freely available)


More on IGF-1 from The influence of zinc supplementation on IGF-1 levels in humans: A systematic review and meta-analysis which was cited for “Previous studies have demonstrated that IGF-1 levels can be affected by several factors.”

“IGF-1 is a growth factor synthesized in the liver, and elicits a myriad of effects on health due to its participation in the GH-IGF-1 axis, where it:

  • Is involved in tissue homeostasis;
  • Has anti-apoptotic, mitogenic, anti-inflammatory, antioxidant and metabolic actions;
  • Contributes to skeletal muscle plasticity, maintenance of muscle strength and muscle mass;
  • Neural and cardiovascular protection;
  • Development of the skeleton;
  • Possesses insulin-like effects, and
  • Is a key factor in brain, eye and lung development during fetal development.

IGF-1 plays important roles in both growth and development, and its levels vary depending on age, with peaks generally observed in the postnatal period and at puberty. IGF-1 levels influence the release of GH [growth hormone] from the hypophysis [pituitary gland] via a negative feedback loop.

A rapid decrease in IGF-1 levels is registered during the third decade of life. Levels gradually decrease between the third and the eighth decade of life.”


The Group 3 “> 12 weeks” finding was reinforced by perspectives such as:

Group 4 “with no comorbidities” was narrowly defined. All of us have degrees of diseases in progress. Consider aging effects:

  • Aging as a normal disease “Aging and its diseases are inseparable, as these diseases are manifestations of aging. Instead of healthy aging, we could use the terms pre-disease aging or decelerated aging.”
  • Aging as an unintended consequence “Epigenetic ageing begins from very early moments after the embryonic stem cell stage and continues uninterrupted through the entire lifespan. Ageing is an unintended consequence of processes that are necessary for development of the organism and tissue homeostasis thereafter.”
  • Organismal aging and cellular senescence “If we assume that aging already starts before birth, it can be considered simply a developmental stage, required to complete the evolutionary program associated with species-intrinsic biological functions such as reproduction, survival, and selection.”
  • An environmental signaling paradigm of aging “The age-phenotype of a cell or organ depends on its environment and not its history. Organisms, organs, and their cells can be reset to different age-phenotypes depending on their environment.”

These perspectives are less important than what each of us choose to do about our own problems. Take responsibility for your one precious life.

Get serious about advanced glycation end products (AGEs)

Ever heard about AGEs? Here are three papers that describe how AGEs affect humans.

First is a 2020 Italian review Common Protective Strategies in Neurodegenerative Disease: Focusing on Risk Factors to Target the Cellular Redox System:

“Neurodegenerative disease is an umbrella term for different conditions which primarily affect the neurons in the human brain. Currently, neurodegenerative diseases are incurable, and the treatments available only control the symptoms or delay the progression of the disease.

Neurotoxicity can be induced by glycation reactions. Since glycation is a nonenzymatic process, proteins characterized by a slow turnover are those that more easily accumulate AGEs.

Methylglyoxal (MG) can occur as glycolysis by-product, but it is also present in foods (especially cooked and baked), beverages (mainly those fermented), and cigarette smoke, and it is considered the most potent precursor of AGE formation. More than 20 different AGEs have been identified in foods and in human tissues.

AGE accumulation, oxidative stress, and inflammation are related to AGE ability to bind specific receptors called RAGE. RAGE expression increases during aging, cancer, cardiovascular diseases, AD [Alzheimer’s], PD [Parkinson’s], and other neurodegenerative diseases.”


A 2015 study by some of the same authors Antiglycative activity of sulforaphane: a new avenue to counteract neurodegeneration? was cited for a treatment in addition to changing one’s diet to be AGE-less.

“When MG production is increased by high glucose or oxidative stress, glycated proteins accumulate in the brain and lead to glycative stress, playing a fundamental role in the establishment of different neurodegenerative disorders.

Our results indicated that SF [sulforaphane] counteracts ROS by two possible mechanisms of action: an increase of intracellular GSH [glutathione] levels and an enhancement of MG-detoxification through the up-regulation of the glyoxalase (GLO1) systems. GLO1 up-regulation is mediated by the transcription factor Nrf2. SF has been demonstrated to activate Nrf2.

Another mechanism by which SF exerts its neuroprotective activity against MG-induced glycative damage is the modulation of mitogen-activated protein kinase (MAPK) signaling pathways involved in apoptotic cell death. All MAPK signaling pathways are activated in AD.

Brain-derived neurotrophic factor (BDNF) is associated with neuronal survival through its interactions with the tyrosine receptor kinase B (TrkB) and p75 cellular receptors. BDNF expression levels are reduced in the brain of AD patients. SF pre-treatment, before MG addition, not only further increased BDNF levels, but also significantly induced TrkB protein levels reverting MG negative effect on this receptor.

SF totally reverts the reduction of glucose uptake caused by MG exposure. SF can be defined as a multitarget agent modulating different cellular functions leading to a pro-survival frame of particular importance in the prevention / counteraction of multifactorial neurodegenerative diseases.”


A 2020 review Non-enzymatic covalent modifications: a new link between metabolism and epigenetics investigated glycation:

“Non-enzymatic covalent modifications (NECMs) by chemically reactive metabolites have been reported to manipulate chromatin architecture and gene transcription. Unlike canonical post-translational modifications (PTMs), NECMs accumulate over time and are much more dependent on the cellular microenvironment.

A. Guanine residues in DNA and RNA can undergo methylglyoxal glycation, thereby inducing DNA and RNA damage. This DNA damage has few corresponding repair pathways.

B. Histones are primary glycation substrates because of their long half-lives and abundant lysine and arginine residues. Histone glycation was found to induce epigenetic dysregulation through three distinct mechanisms:

  1. Competition with essential enzymatic PTMs for sites (e.g., glycation adducts replace H3K4me3 and H3R8me2);
  2. Changing the charge states of histone tails and subsequently affecting the compaction state of the fiber; and
  3. Altering three-dimensional chromatin architecture by inducing both histone-histone and histone-DNA crosslinking.

Epigenetic impacts of histone glycation were shown to be dependent on sugar concentration and exposure time. Histone and DNA glycation may lead to long term epigenetic impacts on immune responses.

C. Glycation of multiple lysine residues of NRF2 inhibits its oncogenic function. Sugar molecules can influence epigenetic events through glycation of transcription factors and/or their associated regulatory proteins.”

The Transcription factor glycation section referenced a 2011 paper Regulation of the Keap1/Nrf2 system by chemopreventive sulforaphane: implications of posttranslational modifications:

“Nrf2 mRNA level is unaffected by treatment with sulforaphane, suggesting that cellular expression of Nrf2 protein is posttranscriptionally regulated. Posttranslational modifications of Keap1 and Nrf2 proteins seem to play an important role in the regulation of ARE‐dependent gene expression.”


“Neurodegenerative diseases are incurable?” Take responsibility for your own one precious life.

Other curated AGEs papers include:

Aging as a normal disease

This 2018 review explained:

“Aging is the sum of all age-related diseases. Aging and its diseases are inseparable, as these diseases are manifestations of aging.

An aged appearance (e.g., grey hair, wrinkles, cushingoid body types and loss of muscles) are manifestations of pre-diseases. For example, an aged appearance may reflect hypercortisolism, sarcopenia, osteoporosis, skin pre-diseases.

Instead of healthy aging, we could use the terms pre-disease aging or decelerated aging. Treatments are generally more effective at pre-disease stages, associated with hyper-function, than at disease stages, associated with functional decline.

The decision to treat or not to treat is often determined by whether it is possible to treat.

A treatment that slows aging increases both healthspan (subclinical period) and lifespan, whereas a treatment that increases lifespan (e.g., coronary bypass, defibrillation) is not necessarily increase healthspan. The goal of both anti-aging therapies and preventive medicine is to extend healthspan (by preventing diseases), thus extending total lifespan.

The fact that aging is an obligatory part of the life of all organisms is not important. Aging can be treated as a pre-disease to prevent its progression to diseases. Aging does not need to be defined as a disease to be treated.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6286826/ “Disease or not, aging is easily treatable”




Take responsibility for your one precious life – Vitamin D3

Where to start among 6,489 studies and reviews published during the past five years, results from a PubMed search of “dihydroxyvitamin D3.” How about:

“Vitamin D plays a fundamental role in body calcium and phosphorous homeostasis, ensuring proper functioning of the skeletomuscular system. Pleiotropic activities include:

  • Anti-inflammatory and immunomodulatory properties (predominantly downregulation of adaptive and upregulation of innate immunity);
  • An important role in reproduction, pregnancy, placental functions and fetal and child development;
  • Important in neurodevelopment as well as in the functioning of the adult central and peripheral nervous system;
  • Regulation of global metabolic and endocrine homeostasis and the functions of different endocrine organs, as well as in the functioning of the cardiovascular system;
  • Inhibits malignant transformation, tumor progression and has anti-cancer properties on a variety of tumors;
  • Formation of the epidermal barrier and hair cycling; and
  • Ameliorating effects on skin cancer and on proliferative and inflammatory cutaneous diseases.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6342654/ “The serum vitamin D metabolome: What we know and what is still to discover”


Or maybe:

“A study in 6,275 American children and adolescents aged 1–21 years showed that 61% were 25-(OH)D3 insufficient and 9% deficient. In adults, up to 40% are 25-(OH)D3 insufficient and 6% deficient.

Once adequate vitamin D values are reached, to further preserve adequate vitamin D levels in adults, the IOM [Institute of Medicine] recommends a daily dose of 600 IU per day, while the Endocrine Society recommends a dose of 600–2000 IU per day (according to the amount of sunlight the individual is exposed to). There seems to be no additional health benefit in doses higher than 4000 IU/day.

Vitamin D supplementation was protective against acute respiratory tract infections in a 25-(OH)D3 deficient population, especially in those receiving daily or weekly supplementation. However, in children this protective effect could not be reproduced.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7281985/ “Vitamin D’s Effect on Immune Function”


Not to forget Advanced glycation end products alter steroidogenic gene expression by granulosa cells: an effect partially reversible by vitamin D:

“This study suggests that there is a relationship between AGEs (advanced glycation end products) and their receptors (RAGE and sRAGE) with vitamin D. Understanding the interaction between AGEs and vitamin D in ovarian physiology could lead to a more targeted therapy for the treatment of ovarian dysfunction.”


Or similarities to broccoli sprouts’ main effect of Nrf2 signaling pathway activation:

“1,25(OH)2D3 plays a role in delaying aging by upregulating Nrf2, inhibiting oxidative stress and DNA damage, inactivating p53‐p21 and p16‐Rb signaling pathways, and inhibiting cell senescence and SASP.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6516172/ “1,25‐Dihydroxyvitamin D exerts an antiaging role by activation of Nrf2‐antioxidant signaling and inactivation of p16/p53‐senescence signaling”


Why do we insist on giving ourselves non-communicable diseases?

I recently paid $22.53 after tax for a nearly two-year supply:

A better use of one’s money would be..?

My June 2020 serum 25-OH Vitamin D measurement was 76 on a scale of 0 to 100 from taking a total of 3,400 IU daily. It’s fat-soluble, so I take it along with 1 gram flax oil each time.

Take responsibility for your own one precious life.

Autism biomarkers and sulforaphane

This 2020 US human study investigated autism improvements with sulforaphane:

“Autism Spectrum Disorder (ASD) is one of the most common neurodevelopmental disorders that, in the United States, is currently estimated to affect 1 out of 59 children who are 8 years old. Despite decades of research and advances in our knowledge of the etiologies of ASD, treatments and biomarkers for ASD remain limited.

The primary diagnosis of ASD still relies on observational tools that are by nature subjective. There are currently no drugs approved to treat the core symptoms of ASD, nor are there any studies using SF [sulforaphane] in genetic mouse models of ASD.

In our previous placebo-controlled, double-blinded, randomized clinical trial, daily administration of SF for 4-18 weeks substantially improved the behavioral abnormalities of the majority of 26 young males with moderate to severe ASD without significant toxicity. The multi-functional phytochemical sulforaphane affects many of the biochemical abnormalities associated with ASD.

We investigated potential molecular markers from three ASD-associated physiological pathways that can be affected by sulforaphane:

  1. Redox metabolism / oxidative stress;
  2. Heat shock response; and
  3. Immune dysregulation / inflammation

in peripheral blood mononuclear cells (PBMCs) from healthy donors and patients with ASD.

Three representative Nrf2 [nuclear factor erythroid 2-related factor 2]-dependent enzymes:

  1. AKR1C1 [aldo-keto reductase family 1 member C1];
  2. NQO1 [dehydrogenase quinone 1]; and
  3. HO-1 [heme oxygenase]

were significantly induced by 6 h of 2 μM or 5 μM SF ex vivo treatments in PBMCs from healthy donors. This time point was chosen based on our earlier observations of the kinetics of upregulation of Nrf2-dependent genes by SF, and was expected to capture the increased mRNA production of both very fast (HO-1) and relatively slow (NQO1) responders.

There was no concentration-dependence in the induction of any of the genes examined, with the higher (5 μM) concentration of SF even showing a slightly diminished effect for the induction of AKR1C1 and NQO1. Although this concentration is achievable in vivo, more typical peak concentrations of SF (and its metabolites) in human plasma are 1-2 μM.

SF ex vivo pre-treatment significantly decreased the LPS [lipopolysaccharides]-stimulated inflammatory gene (

  • COX-2,
  • TNF-α,
  • IL-6 and
  • IL-1β

) expression levels in PBMCs from healthy donors.

As a pilot study for a clinical trial of SF in children with ASD, we evaluated the same biomarkers from the ex vivo studies in 10 young males with ASD, 6-12 years of age, who received SF (in the form of a dietary supplement containing GR [glucoraphanin] and myrosinase), 2.2 μmol/kg/d for 14 days. Grouping by broad functionality (e.g. cytoprotective or pro-inflammatory), differences from baseline were highly significant.

asd gene expression

Individually none is sufficiently specific or sensitive, but when grouped by function as two panels, these biomarkers show promise for monitoring pharmacodynamic responses to sulforaphane in both healthy and autistic humans, and providing guidance for biomedical interventions. We conducted this study in the context of ASD, however our findings have broader implications and suggest that these biomarkers can be used in any study involving an intervention with SF.

Major signaling pathways for protective mechanisms against ASD by SF:

  • (a) Keap1/Nrf2/ARE pathway,
  • (b) NF-κB inflammatory pathway,
  • (c) Heat-shock responses.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7118069/ “Biomarker Exploration in Human Peripheral Blood Mononuclear Cells for Monitoring Sulforaphane Treatment Responses in Autism Spectrum Disorder”


Broccoli sprouts and sulforaphane aren’t panaceas. Their research is becoming more intensive and focused, though.