Month: December 2024

Nrf2 activator rankings

gettingwell4 5+ stars Premium, Epigenetics, Stress ,

A 2024 cell study compared and contrasted findings of previous plant compound Nrf2 inducer studies with a newer assay type:

“Various plants have been reported to contain compounds that promote transcriptional activity of Nuclear factor erythroid 2-related factor 2 (Nrf2) to induce a set of xenobiotic detoxifying enzymes, such as NAD(P)H-quinone acceptor oxidoreductase 1 (NQO1), via the antioxidant response element (ARE). An ARE luciferase reporter assay was recently developed to specifically assess Nrf2 induction potency of compounds.

33 compounds were sorted in the order of their transcriptional activity of Nrf2. CD value is the concentration of a compound required to double the basal activities of individual enzymes or luciferase activity.

nrf2 induction

This study is the first to examine consistency of the transcriptional activity of Nrf2 evaluated using ARE reporter and NQO1 assays for multiple compounds. Future comparisons of CD values by each assay across cell types may be used to demonstrate consistency between the assays, as well as to reveal the factors that influence Nrf2 induction potency.”

https://bmcresnotes.biomedcentral.com/articles/10.1186/s13104-024-07038-6 “Nrf2 induction potency of plant-derived compounds determined using an antioxidant response element luciferase reporter and conventional NAD(P)H-quinone acceptor oxidoreductase 1 activity assay”

A 2019 ranking of sulforaphane with 18 other Nrf2 activators was curated in Part 2 of Rejuvenation therapy and sulforaphane, and pointed out bioavailability differences:
OMCL2019-2716870.006

It [sulforaphane] is not only a potent Nrf2 inducer but also highly bioavailable [around 80%], so that modest practical doses can produce significant clinical responses. Other Nrf2 activators [shown in the above image] not only lack potency, but also lack the bioavailability to be considered as significant intracellular Nrf2 activators.”

This study attempted to explain differences in the two assay findings with numerous “may” and “could” statements. Okay.

But if you want to activate your body’s endogenous detoxification and antioxidant systems with a natural plant compound, sulforaphane remains the number one choice.

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Too dangerous to investigate?

gettingwell4 0-1 star Wasted resources, Hippocampus, Immune system, Limbic system, Memory , ,

This blog’s 1100th curation is a clinical trial of ergothioneine’s effects on cognitive decline:

“We recruited participants aged between 60–90 years of age, from three study cohorts diagnosed with mild cognitive impairment (MCI) and provided them with ergothioneine (ET)  (25 mg capsules administered orally three times a week) or placebo in a double-blinded and randomized manner. Blood samples were collected at baseline and quarterly (visits 1, 4, 7, 10, 14) for clinical safety assessment and biomarker analyses). Neuro-cognitive assessments were conducted biannually (visits 7 and 14).

Following ET intake, an increase in Z-scores was observed in the Rey Auditory Verbal Learning Test (RAVLT) (immediate and delayed recalls), which evaluates learning ability and memory.

ravlt

wbc

Participants in both ET and placebo groups recorded a lower total white blood cell count compared to baseline at visit 7, both of which recovered subsequently. The reasons for this anomaly are unclear but values were all still within the expected range for their age.”

https://journals.sagepub.com/doi/epub/10.1177/13872877241291253 “Investigating the efficacy of ergothioneine to delay cognitive decline in mild cognitively impaired subjects: A pilot study”

I rated this study a waste of time and money for the researchers’ incurious lack of following where their data led. Significant WBC signals of both treatment and placebo subjects’ immune system responses were shrugged off with an “expected range” non-explanation.

What can’t white tea do?

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An effusive 2024 review of white tea’s beneficial effects:

“This comprehensive examination contributes nuanced perspectives, paving the way for continued research, innovation, and integration of white tea into diverse consumer preferences. Overall, white tea emerges as a multifaceted beverage with far-reaching implications for health, wellness, and the future landscape of the tea industry.”

white tea

https://www.sciopen.com/article/10.26599/FSHW.2024.9250424 “New insights into chemical compositions and health benefits of white tea and development of new products derived from white tea” (click pdf link)

I didn’t see a mention of white tea drinkers’ ability to levitate and fly the astral plane like the Red Bull commercials. Maybe it’s just obvious?

TFEB and autophagy

gettingwell4 2-3 stars Required further work, Stress ,

Two 2024 papers that cited Precondition your defenses with broccoli sprouts, starting with an in vitro study of influences on auditory cell function:

“Although various studies have focused on the effect of oxidative stress on the inner ear as an inducer of age-related hearing loss (ARHL), there are no effective preventive approaches for ARHL.

We focused on the function of TFEB and the impact of intracellular ROS as a potential target for ARHL treatment in a NaAsO2-induced auditory premature senescence model. Our results suggested that short exposure to NaAsO2 leads to DNA damage, lysosomal damage and mitochondrial damage in auditory cells, triggering temporary signals for TFEB transport into the nucleus and, as a result, causing insufficient autophagic flux and declines in lysosomal function and biogenesis and mitochondrial quality.

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This is the first report to indicate that the inactivation of TFEB directly causes oxidative stress (NaAsO2)-induced premature auditory senescence and SASP induction via decreases in autophagic flux and lysosomal dysfunction, with a lowered pH at the transcriptional level and, as a consequence, ROS production with decreasing mitochondrial quality in auditory cells. The activator of TFEB might have a pivotal antiaging effect in the inner ear.”

https://www.nature.com/articles/s41420-024-02139-4 “Premature senescence is regulated by crosstalk among TFEB, the autophagy lysosomal pathway and ROS derived from damaged mitochondria in NaAsO2-exposed auditory cells”

These researchers used exposure concentrations and durations that had no relevance to humans. Human irrelevance made it difficult to assess the above graphic that shows both TFEB activation and inactivation as stress-related. “No effective preventive approaches for ARHL” was asserted as a given, although “TFEB activation via transport into the nucleus contributes to anti-senescence activity in auditory cells and represents a new therapeutic target for ARHL” was also stated.

Just like the two papers in Eat broccoli sprouts for your hearing, preconditioning’s importance wasn’t investigated. So this study didn’t have findings about how mild TFEB activation or inactivation might precondition auditory cells for other stress that might damage hearing.

Next is a review of muscle regeneration and autophagy:

“Satellite cells, also known as muscle stem cells when activated, are essential for muscle repair. These adult stem cells typically remain in a dormant state. In response to tissue injury, these cells are rapidly activated and divided to generate new stem cells, which proliferate to form myoblasts, which further differentiate into myocytes to repair damaged muscle tissue. However, muscle regeneration can be significantly impaired under various conditions due to dysfunctional satellite cell activity.

mTORC1 activity is suppressed during amino acid starvation, leading to autophagy activation. Under these conditions, TFEB, TFE3, and MITF translocate to the nucleus, where they enhance the transcription of genes involved in autophagy and lysosomal function. When nutrients are abundant, mTORC1 suppresses autophagy. This inhibition ensures that resources are directed toward growth and proliferation rather than cellular recycling.

Chronic injuries are typically associated with sustained metabolic or oxidative stress, leading to prolonged or impaired autophagy. While autophagy serves a compensatory and beneficial role in acute injuries, its role in chronic muscle diseases is more complex. On the one hand, autophagy alleviates oxidative stress and mitigates aging. On the other hand, dysregulated autophagy may contribute to muscle fibrosis and loss of muscle mass.

The function of autophagy varies across different stages of satellite cell activity. Autophagy:

  1. Maintains cellular homeostasis by clearing damaged organelles.
  2. Preserves the number of satellite cells by antagonizing apoptosis.
  3. Sustains the quiescence of satellite cells by reducing reactive oxygen species (ROS).
  4. Promotes the activation of satellite cells by supplying energy.
  5. Facilitates the differentiation of satellite cells by mitochondrial remodeling.”

ijms-25-11901-g003-550

https://www.mdpi.com/1422-0067/25/22/11901 “Autophagy in Muscle Regeneration: Mechanisms, Targets, and Therapeutic Perspective”

I’ve curated a few other of the 110 papers that cited the 2020 “Sulforaphane activates a lysosome-dependent transcriptional program to mitigate oxidative stress” over the years, to include:

Sulforaphane’s effects on autism and liver disease;

Bridging Nrf2 and autophagy; and

Eat broccoli sprouts to maintain your cells.

Polyphenol Nrf2 activators

gettingwell4 2-3 stars Required further work, Acetylcholine, Amygdala, Cerebrum, Cortisol, Dopamine, Epigenetics, Glutamate, Hippocampus, Hypothalamus, Immune system, Limbic system, Memory, Neurochemicals, Oxytocin, Serotonin, Stress, Vasopressin , , , , ,

Two 2024 reviews by the same group that published Sulforaphane in the Goldilocks zone investigated dietary polyphenols’ effects as “hormetic nutrients”:

“Polyphenols display biphasic dose–response effects by activating at a low dose the Nrf2 pathway resulting in the upregulation of antioxidant vitagenes [see diagram]. We aimed to discuss hormetic nutrients, including polyphenols and/or probiotics, targeting the Nrf2 pathway and vitagenes for the development of promising neuroprotective and therapeutic strategies to suppress oxidative stress, inflammation and microbiota deregulation, and consequently improve cognitive performance and brain health.

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Hormetic nutrition through polyphenols and/or probiotics targeting the antioxidant Nrf2 pathway and stress resilient vitagenes to inhibit oxidative stress and inflammatory pathways, as well as ferroptosis, could represent an effective therapy to manipulate alterations in the gut microbiome leading to brain dysfunction in order to prevent or slow the onset of major cognitive disorders. Notably, hormetic nutrients can stimulate the vagus nerve as a means of directly modulating microbiota-brain interactions for therapeutic purposes to mitigate or reverse the pathophysiological process, restoring gut and brain homeostasis, as reported by extensive preclinical and clinical studies.”

https://www.mdpi.com/2076-3921/13/4/484 “Hormetic Nutrition and Redox Regulation in Gut–Brain Axis Disorders”

I’m not onboard with this study’s probiotic assertions because most of the cited studies contained unacknowledged measurement errors. Measuring gut microbiota, Part 2 found:

“The fecal microbiome does not represent the overall composition of the gut microbiome. Despite significant roles of gut microbiome in various phenotypes and diseases of its host, causative microbes for such characteristics identified by one research fail to be reproduced in others.

Since fecal microbiome is a result of the gut microbiome rather than the representative microbiome of the GI tract of the host, there is a limitation in identifying causative intestinal microbes related to these phenotypes and diseases by studying fecal microbiome.”

These researchers also erroneously equated isothiocyanate sulforaphane’s Nrf2-activating mechanisms with polyphenols activating Nrf2.

This research group did better in clarifying polyphenols’ mechanisms in a review of hormetic dose-response effects of the polyphenol rosmarinic acid:

“This article evaluates whether rosmarinic acid may act as a hormetic agent, mediating its chemoprotective effects as has been shown for similar agents, such as caffeic acid, a derivative of rosmarinic acid.

Rosmarinic acid enhanced memory in institute of cancer research male mice in the Morris water maze (escape latency).

untitled

Of importance in the evaluation of rosmarinic acid are its bioavailability, metabolism, and tissue distribution (including the capacity to affect and/or cross the BBB and its distribution and half-life within the brain). In the case of polyphenols, including rosmarinic acid, they are typically delivered at low doses in the diet and, in most instances, they do not escape first-pass metabolism, with the prominent chemical forms being conjugates of glucuronides and sulfates, with or without methylation.

These conjugated metabolites are chemically distinct from the parent compound, showing considerable differences in size, polarity, and ionic form. Their biological actions are quite different from the parent compound.

Bioavailability studies reveal that maximum concentrations in plasma typically do not exceed 1 µM following consumption of 10–100 mg of a single phenolic compound, with the maximum concentration occurring typically less than 2 h after ingestion, then dropping quickly thereafter. In the case of the in vitro studies assessed herein, and with few exceptions, most of the studies employed concentrations >10 µM with some studies involving concentrations in the several hundred µM range, with the duration of exposure typically in the range of 24–72 h, far longer duration than the very short time interval of a few minutes to several hours in human in vivo situations.

We strongly recommend that all experiments using in vitro models to study biological responses to dietary polyphenols use only physiologically relevant flavonoids and their conjugates at appropriate concentrations, provide evidence to support their use, and justify any conclusions generated. When authors fail to do this, referees and editors must act to ensure that data obtained in vitro are relevant to what might occur in vivo.”

https://www.degruyter.com/document/doi/10.1515/med-2024-1065/html “The chemoprotective hormetic effects of rosmarinic acid”

Failed aging paradigms

gettingwell4 2-3 stars Required further work, Brain development, Epigenetics, Memory , , , ,

A 2024 paper with 81 coauthors presented different views of aging:

“This article highlights the lack of consensus among aging researchers on fundamental questions such as the definition, causes, and onset of aging as well as the nature of rejuvenation. Our survey revealed broad disagreement and no majority opinion on these issues.

We obtained 103 responses (∼20% of which were submitted anonymously). The respondents included 29.8% professors, 25% postdoctoral fellows, 22.1% graduate students, 13.5% industry professionals, and 9.6% representing other categories (a total of eight additional groups).

When does aging begin? At 20 years (22%), gastrulation (18%), conception (16.5%), gametogenesis (13%), 25 years (11%), birth (8%), 13 years (5%), and 9 years (4%). Nobody chose the only remaining option (30 years).

m_pgae499f3

It is clear from responses that aging remains an unsolved problem in biology. While most scientists think they understand the nature of aging, apparently their understanding differs. Where some may stress the importance of targeting underlying mechanisms, others focus on ameliorating the phenotypes.”

https://academic.oup.com/pnasnexus/article/3/12/pgae499/7913315?login=false “Disagreement on foundational principles of biological aging”

I’ll assert that these researchers were unable to incorporate information outside of their chosen paradigm. This would explain why only 18% understood the embryonic stage of gastrulation as aging’s start, although the 2022 paper Epigenetic profiling and incidence of disrupted development point to gastrulation as aging ground zero in Xenopus laevis provided epigenetic clock evidence that:

“It is not birth, marriage, or death, but gastrulation which is truly the most important time in your life.”

I’ve cited Josh Mitteldorf’s work about aging a few times. His paradigm of aging is in his 2017 book Cracking the Aging Code: The New Science of Growing Old – And What It Means for Staying Young that:

“Aging has an evolutionary purpose: to stabilize populations and ecosystems.”

However, there isn’t evidence of such causal inheritance mechanisms that would begin an organism’s aging during embryogenesis, i.e., that an embryo’s development of aging elements at gastrulation is causally affected by population and ecosystem factors.

Dr. Goodenowe recently had a casual conversation Episode 8 – Perpetual Health, Exploring The Science Behind Immortality where he asserted items such as:

“What we’re all fighting is entropy. Entropy is the tendency of all things to reach a level of randomness. Aging is not a disease. It’s just apathy and entropy. The body just doesn’t care – people don’t pay attention.

This notion that we are programmed for death is wrong. We’re not programmed to die. We actually teach ourselves to die. The body learns how to die, so as your function decreases, it adjusts. It appears to be programmed because of the association with chronological age.”

I haven’t seen any of his papers that put these and his other assertions up for review. For example, I doubt the entropy-caused randomness assertion would survive peer review per Stochastic methylation clocks?:

“Entropic theories of aging have never been coherent, but they are nevertheless experiencing a resurgence in recent years, primarily because neo-Darwinist theories of aging are all failing. I find this ironic, because the neo-Darwinist theories arose precisely because scientists realized that the Second Law of Thermodynamics does not apply to living systems.”

The funny thing about failed aging paradigms is that quite a few of their treatments improve healthspan, but not lifespan. If they don’t “target aging underlying mechanisms” they “ameliorate aging phenotypes.” None so far have positively affected both human healthspan and lifespan.

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