Ancient DNA fragments enable adult neurogenesis

A 2025 rodent study investigated mechanisms by which erythropoietin (EPO) enables adult neurogenesis and cognitive function:

“We mapped epigenomic and transcriptional landscapes of adult mouse hippocampus under recombinant human EPO (rhEPO) treatment. We discovered significant lineage-specific remodelling of chromatin accessibility predominantly in newly formed pyramidal neurons, highlighting a robust EPO-driven neurogenic response. Notably, transposable elements (TEs), particularly ancient LINEs and SINEs, emerged as critical cis-regulatory elements (cCREs).

EPO is known to be upregulated in the brain under hypoxic or injury conditions, and it has been considered a natural neuroprotective agent. We demonstrated that EPO, a traditionally hematopoietic hormone, can profoundly reprogram the adult neural epigenome to drive neurogenesis.

EPO may activate a specific subclass of dormant regulatory elements to drive nearby genes. Such a mechanism would represent a previously unappreciated mode of gene regulation: the de novo recruitment of ancient genomic elements to drive a contemporary cellular response.

Our data support the model that EPO drives differentiation of progenitors rather than inducing widespread cell division. The net effect is an enrichment of pyramidal neurons at the cost of interneurons. Pyramidal neurons integrate in the hippocampal circuitry, leading to potential implications for mood, memory, cognitive enhancement, and recovery from brain injury.

We propose a conserved evolutionary mechanism at play: ancient TEs embedded in the genome have been repurposed as cCREs in neural cells, and during an EPO-induced neurogenic stimulus, the brain taps into this reservoir of regulatory elements to rapidly reshape gene expression. In evolutionary terms, this represents an efficient strategy.”

https://www.biorxiv.org/content/10.1101/2025.10.13.682070v1.full “Transposable Element-Mediated Epigenomic Remodeling Drives Erythropoietin-Induced Neurogenesis in the Adult Hippocampus”


Activating Nrf2 pathways with sunlight

A 2025 review subject was non-electrophilic Nrf2 activators:

“NRF2 can be induced via:

  1. Non-specific electrophile/ROS generation,
  2. Disruption of the NRF2–KEAP1 protein–protein interaction,
  3. Autophagy-mediated KEAP1 degradation,
  4. Direct modulation of NRF2 protein stability, and
  5. Post-transcriptional/post-translational modifications.

Except for a single intervention, therapeutic hypothermia, every non-pharmacological strategy with defined mechanisms employs more than one of these routes, most frequently pairing post-translational modification with either protein-stability regulation or limited electrophile production. This combinatorial activation elevates both NRF2 abundance and transcriptional competence while minimizing the liabilities of purely electrophilic agents and circumventing the efficacy limitations.

Classical electrophilic NRF2 activators, despite potent activation potential, exhibit paradoxically reduced therapeutic efficacy relative to single antioxidants, attributable to concurrent oxidative stress generation, glutathione depletion, mitochondrial impairment, and systemic toxicity. Although emerging non-electrophilic pharmacological activators offer therapeutic potential, their utility remains limited by bioavailability and suboptimal potency.”

https://www.mdpi.com/2076-3921/14/9/1047 “Non-Electrophilic Activation of NRF2 in Neurological Disorders: Therapeutic Promise of Non-Pharmacological Strategies”


These researchers exaggerated problems of electrophilic Nrf2 activators such as “mitochondrial impairment, and systemic toxicity” so they could have something to write about. Just like every intervention, the dose determines the response. I can’t imagine not eating broccoli sprouts in favor of brain zapping with electroconvulsive therapy or transcranial magnetic stimulation just to avoid sulforaphane’s temporary mild oxidative stress that activates Nrf2 for 15-20 minutes.

But there are limitations to how an unwell person can benefit from Nrf2 activation. For example, I haven’t curated many cancer papers because healthy body functioning can’t be assumed.

I walk the beach at sunrise, weather permitting, because it makes me feel good, and I’m always happy afterwards that I made the effort to get outside. That doing so combines two of the above non-electrophilic Nrf2 activators, physical exercise and photobiomodulation, hasn’t been a consideration.

These reviewers didn’t include human studies of sunlight’s effects. Nevermind that hospitals used to have sundecks for patients, and John Ott published relevant human and animal studies over fifty years ago.


Many studies have an undisclosed limitation in that they were performed without controlling for light. For example, knowing that mitochondria are light-activated, I don’t trust those studies’ in vivo, ex vivo, or in vitro results.

None of the 100 most recent 2025 photobiomodulation papers examined natural sunlight. Maybe it wouldn’t sell red light, green light, and blue light lasers and other products to show that people could produce the same effects themselves with sunlight at different times of the day? Would researchers damage their reputations to study a freely-available intervention, one where they don’t “do something”?

Glucosinolate and isothiocyanate human interventions

A 2025 review covered human evidence from glucosinolate and isothiocyanate research through April 2025:

“Glucosinolates (GSLs) and their breakdown products, isothiocyanates (ITCs), are biogenesis compounds with anti-inflammatory, antioxidant, and anticancer properties, mediated through key pathways such as Nrf2, NF‐κB, and epigenetic regulation. However, their limited and variable bioavailability remains a key challenge. This review summarises the current clinical evidence on GSLs and ITCs, with a focus on their health effects and metabolic fate in humans.”

https://www.mdpi.com/2304-8158/14/16/2876 “Bioavailability, Human Metabolism, and Dietary Interventions of Glucosinolates and Isothiocyanates: Critical Insights and Future Perspectives”


In the above graphic, notice how the inactive myrosinase column has no small intestine participation, but the active myrosinase column does. This point wasn’t adequately emphasized, that for complete effects, an individual has to do whatever they can to thoroughly chew or otherwise activate myrosinase to hydrolyze glucosinolates before swallowing.

Researchers don’t rely on individuals taking responsibility for their own health, of course. Just swallow these pills, we’ll do it for you, as if humans are lab rats. This lack of emphasis is understandable, if not optimal.

This review provided longish coverage of studies, which is preferable to the usual treatment of citing a reference without much explanation. Compare, for example, my longish curation of the 2023 Eat broccoli sprouts for your high intensity interval training with its reference 68 summary below:

“Another study investigated the effects of consuming GSL-rich broccoli sprout (GRS) supplements on oxidative stress and physiological adaptations to intense exercise training. In a randomised, double-blind, crossover design, nine healthy participants consumed either a GRS supplement (75 g of sprouts) or a placebo twice daily over a 7-day high-intensity interval training period. The findings revealed that GRS supplementation significantly reduced markers of oxidative stress, including carbonylated proteins in skeletal muscle and plasma myeloperoxidase levels, compared to the placebo condition. Furthermore, GRS intake led to reduced lactate accumulation during submaximal exercise and enhanced exercise performance, as indicated by a longer time to exhaustion during maximal exercise tests. At the molecular level, supplementation with GRS was associated with elevated Nrf2 protein levels in muscle tissue, suggesting activation of endogenous antioxidant defence mechanisms. In addition, GRS intake mitigated nocturnal hypoglycaemic episodes and lowered average blood glucose levels, indicating improved glucose regulation during intense training. Collectively, these results suggest that GRS supplementation may enhance physiological adaptations to high-intensity exercise by reducing oxidative stress and supporting metabolic homeostasis.”


Get a little stress into your life, Part 2

A 2025 reply to a letter to the editor cited 56 references to elaborate on Part 1 and related topics:

“A positive effect does not necessarily mean benefit, and positive effects on individual organisms may mean adverse effects on other coexisting organisms. However, a vast literature shows that hormetic stimulation can result in benefits depending on the context, for instance, clear growth, yield, and survival improvement.

There is some energetic cost to support hormetic stimulation, with a likely positive energy budget, which might also have negative consequences if there is insufficient energy substrate, especially under concurrent severe environmental challenges. Moreover, hormetic preconditioning could be particularly costly when there is a mismatch between the predicted environment and the actual environment the same individuals or their offspring might face in the future.

Hormesis should not be unilaterally linked to positive and beneficial effects without considering dose levels. For any research to answer the question of whether a stimulation represents hormesis and whether it is beneficial, robust dose–response evaluations are needed, which should be designed a priori for this purpose, meeting the requirements of the proper number, increment, and range of doses.

Both additivity and synergism are possible in the hormetic stimulatory zone, depending also on the duration of exposure and the relative ratio of different components. This might happen, for example, when a chemical primes stress pathways (e.g., heat shock proteins and antioxidants), thus enabling another chemical to trigger hormesis (defense cross-activation) and/or because combined low subtoxicity may modulate receptors (e.g., aryl hydrocarbon receptor and nuclear factor erythroid 2-related factor 2) differently than individual exposures (receptor binding synergy).

Moreover, even when stimulation occurs in the presence of individual components, stimulation may no longer be present when combined, and therefore, effects of mixtures cannot be accurately predicted based on the effects of individual components. There may be hormesis trade-offs; hormesis should be judged based on fitness-critical end points.

While often modeled mathematically, hormesis is fundamentally a dynamic biological process and should not be seen as a purely mathematical function, certainly not a linear one. Much remains to be learned about the role of hormesis in global environmental change, and an open mind is needed to not miss the forest for the trees.”

https://pubs.acs.org/doi/10.1021/acs.est.5c05892 “Correspondence on ‘Hormesis as a Hidden Hand in Global Environmental Change?’ A Reply”


Reference 38 was a 2024 paper cited for:

“Hormetic-based interventions, particularly priming (or preconditioning), do not weaken organisms but strengthen them, enhancing their performance and health under different environmental challenges, which are often more massive than the priming exposure.

The catabolic aspect of hormesis is primarily protective whereas the anabolic aspect promotes growth, and their integration could optimize performance and health. The concept of preconditioning has also gained widespread attention in biomedical sciences.”

https://www.sciencedirect.com/science/article/abs/pii/S1568163724004069 “The catabolic – anabolic cycling hormesis model of health and resilience” (not freely available)


Reference 40 was a 2021 review that characterized hormesis as a hallmark of health:

“Health is usually defined as the absence of pathology. Here, we endeavor to define health as a compendium of organizational and dynamic features that maintain physiology.

Biological causes or hallmarks of health include features of:

  • Spatial compartmentalization (integrity of barriers and containment of local perturbations),
  • Maintenance of homeostasis over time (recycling and turnover, integration of circuitries, and rhythmic oscillations), and
  • An array of adequate responses to stress (homeostatic resilience, hormetic regulation, and repair and regeneration).

Disruption of any of these interlocked features is broadly pathogenic, causing an acute or progressive derailment of the system.

A future ‘medicine of health’ might detect perilous trajectories to intercept them by targeted interventions well before the traditional ‘medicine of disease’ comes into action.”

https://www.sciencedirect.com/science/article/pii/S0092867420316068 “Hallmarks of Health”


Betaine as an exercise mimetic

A 2025 human study investigated effects of long-term exercise:

“Exercise has well-established health benefits, yet its molecular underpinnings remain incompletely understood. We conducted an integrated multi-omics analysis to compare effects of acute vs. long-term exercise in healthy males.

Acute exercise induced transient responses, whereas repeated exercise triggered adaptive changes, notably reducing cellular senescence and inflammation and enhancing betaine metabolism. Exercise-driven betaine enrichment, partly mediated by renal biosynthesis, exerts geroprotective effects and rescues age-related health decline in mice.

Betaine binds to and inhibits TANK-binding kinase 1 (TBK1), retarding the kinetics of aging.

Betaine effectively alleviated senescence phenotypes by reduced senescence-associated β-galactosidase (SA-β-Gal)-positive cells, decreased p21 expression, lowered DNA damage indicator γ-H2A.X, and elevated heterochromatin mark H3K9me3. Betaine treatment also enhanced cellular antioxidant capacity, as evidenced by increased NRF2 phosphorylation and reduced ROS accumulation.

These findings systematically elucidate the molecular benefits of exercise, and position betaine as an exercise mimetic for healthy aging.”

https://doi.org/10.1016/j.cell.2025.06.001 “Systematic profiling reveals betaine as an exercise mimetic for geroprotection” (not freely available) Thanks to Dr. Weimin Ci for providing a copy.


Eat broccoli sprouts for your eyes, Part 3

Two 2025 papers cited Precondition your defenses with broccoli sprouts, starting with a review of age-related macular degeneration:

“AMD progression from intermediate to late AMD leads to a point of irreversible retinal pigmented epithelium (RPE) degeneration where treatment becomes worthless. Treating patients at the early/intermediate stages presents a better therapeutic window opportunity for AMD as the disease could potentially be prevented or slowed down.

Strong evidence points to RPE dysfunction at these stages, mainly through redox imbalance and lysosomal dysfunction in RPE oxidative injury. Restoring oxidative balance and lysosomal function may act as preventive and therapeutic measures against RPE dysfunction and degeneration.

Due to interaction with KEAP1, NRF2 is a ubiquitously expressed protein with a high turnover and half-life of about 20 minutes. Because the turnover of NRF2 is faster than KEAP1, newly synthesized NRF2 does not have free KEAP1 to bind and is translocated into the nucleus. Once in the nucleus, NRF2 dimerizes with sMAF and the complex binds to antioxidant response element (ARE) sequences, promoting the expression of ARE genes.

There is NRF2 involvement in most of the hallmarks of aging. Key transcriptional regulatory factors of related pathways, such as transcription factor EB (TFEB) and NRF2, may be targeted to restore homeostasis and/or prevent further RPE degeneration.”

https://www.mdpi.com/2076-3921/14/5/596 “Targeting Lysosomal Dysfunction and Oxidative Stress in Age-Related Macular Degeneration”

There were other informative tidbits throughout this review, such as:

  • “Anti-inflammatory effects of most electrophilic NRF2 activators are thought to be at least partly NRF2-independent, suggesting that these compounds lacking specificity may be advantageous for multitargeted pathologies.
  • TFEB can activate NRF2 under conditions devoid of oxidative stress.”

This paper also cited Bridging Nrf2 and autophagy when discussing the above graphic.


In this human cell and rodent study, several coauthors of the original 2020 study tested sulforaphane and TFEB interactions for ameliorating effects of a rare disease:

“Mutations in genes encoding lysosomal proteins could result in more than approximately 70 different lysosomal storage disorders. Niemann–Pick disease type C (NPC) is a rare lysosomal storage disorder caused by mutation in either NPC1 or NPC2 gene. Deficiency in NPC1 or NPC2 protein results in late endosomal/lysosomal accumulation of unesterified cholesterol.

Clinical symptoms of NPC include hepatosplenomegaly, progressive neurodegeneration, and central nervous system dysfunction, that is, seizure, motor impairment, and decline of intellectual function. So far there is no FDA-approved specific therapy for NPC.

Under stress conditions, that is, starvation or oxidative stress, TFEB is dephosphorylated and actively translocates into the nucleus, promoting expression of genes associated with lysosome and autophagy. TFEB overexpression or activation results in increased number of lysosomes, autophagy flux, and exocytosis.

Pharmacological activation of TFEB by sulforaphane (SFN), a previously identified TFEB agonist, significantly promoted cholesterol clearance in human and mouse NPC cells, while genetic inhibition (KO) of TFEB blocked SFN-induced cholesterol clearance. This clearance effect exerted by SFN was associated with upregulated lysosomal exocytosis and biogenesis. SFN treatment has no effect on the liver and spleen enlargement of Npc1 mice.

SFN is reportedly BBB-permeable, assuring a good candidate for efficient delivery to the brain, which is essential for targeting neurodegenerative phenotypes in neurological diseases including NPC. This is the first time that SFN was shown to directly activate TFEB in the brain.

Collectively, our results demonstrated that pharmacological activation of TFEB by a small-molecule agonist can mitigate NPC neuropathological symptoms in vivo. TFEB may be a putative target for NPC treatment, and manipulating lysosomal function via small-molecule TFEB agonists may have broad therapeutic potential for NPC.”

https://elifesciences.org/articles/103137 “Small-molecule activation of TFEB alleviates Niemann–Pick disease type C via promoting lysosomal exocytosis and biogenesis”


Eat broccoli sprouts to alleviate diabetic heart disease

A 2025 rodent study investigated sulforaphane’s effects on diabetic cardiomyopathy:

“The protective effect of cruciferae-derived sulforaphane (SFN) on diabetic cardiomyopathy (DCM) has garnered increasing attention. However, no studies have specifically explored its mechanistic involvement in cardiac substrate metabolism and mitochondrial function.

To address this gap, Type 2 diabetes mellitus (T2DM) db/db mice were orally gavaged with vehicle or 10 mg/kg body weight SFN every other day for 16 weeks, with vehicle-treated wild-type mice as controls. SFN intervention (SFN-I) alleviated hyperglycemia, dyslipidemia, HOMA-IR, serum MDA levels, and liver inflammation. SFN-I improved the lipotoxicity-related phenotype of T2DM cardiomyopathy, manifested as attenuation of diastolic dysfunction, cardiac injury, fibrosis, lipid accumulation and peroxidation, ROS generation, and decreased mitochondrial complex I and II activities and ATP content.

Although not fully understood, multiple systemic and cardiac-local mechanisms contribute to DCM, encompassing hyperglycemia, dyslipidemia, insulin resistance (IR), disturbances in cardiac substrate metabolism, lipotoxicity, glucotoxicity, mitochondrial dysfunction, oxidative stress, inflammation, and endoplasmic reticulum (ER) stress. Nrf2 and its downstream metallothionein also mediated the preventive effect of SFN on DCM, and may underlie the synergistic effect of SFN and zinc in DCM.

These results suggest that chronic oral SFN-I protects against DCM by mitigating overall metabolic dysregulation and inhibiting cardiolipotoxicity. The latter might involve controlling cardiac fatty acid metabolism and improving mitochondrial function, rather than promoting glucose metabolism.”

https://www.mdpi.com/2076-3921/14/5/603 “Oral Sulforaphane Intervention Protects Against Diabetic Cardiomyopathy in db/db Mice: Focus on Cardiac Lipotoxicity and Substrate Metabolism”


This study had numerous charts like the above showing it was better to not have a deviation from health (Ctrl) rather than incur injury (DCM) then try to fix it with sulforaphane (DCM + SFN). But the control group was wild-type mice, not mice genetically inclined to diabetes like the treatment groups.

The subjects’ starting points were at nine-weeks-old (equivalent to 18-25 year-old humans), and duration was 16 weeks. Grok 3 said: “A 25-week-old db/db mouse is roughly equivalent to a human aged 30–35 years chronologically, though its metabolic condition may mimic older human physiological states in diabetes and obesity research.”

A human equivalent of a 10 mg/kg sulforaphane dose is (.081 x 10 mg) = 56 mg orally administered every other day. That’s about how much total sulforaphane I estimated I took every day (52 mg) from Week 6 through Week 56 by eating microwaved broccoli sprouts twice daily.

No rationale was provided for the sulforaphane dose or the every-other-day dosing regimen. Since I took ~52 mg every day for almost a year, I’ll guess that this study may have had more definitive results with daily dosing. Or maybe add zinc per Zinc and broccoli sprouts – a winning combination.

Nrf2 activators and transcriptomic clocks

Two preprint studies looked at making transcriptional aging clocks using Nrf2 activators. Let’s start with a 2025 nematode study that used constant exposure to sulforaphane at different concentrations:

“To explore the potential of sulforaphane as a candidate natural compound for promoting longevity more generally, we tested the dose and age-specific effects of sulforaphane on C. elegans longevity, finding that it can extend lifespan by more than 50% at the most efficacious doses, but that treatment must be initiated early in life to be effective. We then created a novel, gene-specific, transcriptional aging clock, which demonstrated that sulforaphane-treated individuals exhibited a “transcriptional age” that was approximately four days younger than age-matched controls, representing a nearly 20% reduction in biological age.

The clearest transcriptional responses were detoxification pathways, which, together with the shape of the dose-response curve, indicates a likely hormetic response to sulforaphane. The hormetic, stress-pathway inducing properties of sulforaphane may indicate that many beneficial dietary supplements work in a fairly generic fashion as mild toxins rather than being driven by the biochemical properties of the compounds themselves (e.g., as antioxidants).

These results support the idea that robust longevity-extending interventions can act via global effects across the organism, as revealed by systems level changes in gene expression.”

https://www.biorxiv.org/content/10.1101/2025.05.11.653363v1 “The broccoli derivative sulforaphane extends lifespan by slowing the transcriptional aging clock”

There are difficulties in researchers translating nematode studies to mammals and humans. Nematodes lack a homolog to the Keap1 protein, which is sulforaphane’s main mammalian target to activate Nrf2.


A 2024 study developed various mammalian epigenetic clocks:

“A unified transcriptomic model of mortality that encompasses both aging and various models of lifespan-shortening and longevity interventions (i.e., mortality clocks) has been lacking. We conducted an RNA-seq analysis of mice subjected to 20 compound treatments in the Interventions Testing Program (ITP).

We sequenced the transcriptomes of a large cohort of ITP mice subjected to various neutral and longevity interventions, expanded the dataset with publicly available gene expression data representing organs of mice and rats across various strains and lifespan-regulating interventions, connected these models with survival data, and performed a meta-analysis of aggregated 4,539 rodent samples, which allowed us to identify multi-tissue transcriptomic signatures of aging, mortality rate, and maximum lifespan.

Aging and mortality were characterized by upregulation of genes involved in inflammation, complement cascade, apoptosis, and p53 pathway, while oxidative phosphorylation, fatty acid metabolism, and mitochondrial translation were negatively associated with mortality, both before and after adjustment for age.

Utilizing the aggregated dataset, we developed rodent multi-tissue transcriptomic clocks of chronological age, lifespan-adjusted age, and mortality. While the chronological clock could distinguish the effect of detrimental genetic and dietary models, it did not show a decrease in biological age in response to longevity interventions. In contrast, clocks of lifespan-adjusted age and mortality both captured aging-associated dynamics and correctly predicted the effect of lifespan-shortening and extending interventions.

Transcriptomic biomarkers developed in this study provide an opportunity to identify interventions promoting or counteracting molecular mechanisms of mortality, and characterize specific targets associated with their effects at the level of cell types, intracellular functional components, and individual genes. Our study underscores the complexity of aging and mortality mechanisms, the interplay between various processes involved, and the clear potential for developing therapies to extend healthspan and lifespan.”

https://www.biorxiv.org/content/10.1101/2024.07.04.601982v1.full “Transcriptomic Hallmarks of Mortality Reveal Universal and Specific Mechanisms of Aging, Chronic Disease, and Rejuvenation”


This second study’s references included an ITP study curated in Astaxanthin and aging, which stated:

“Despite the fact that the average diet contained 1840 ppm astaxanthin (only 46% of the target), median lifespans of male UM-HET3 mice were significantly improved. Amounts of dimethyl fumarate (DMF) in the diet averaged 35% of the target dose, which may explain the absence of lifespan effects.”

So screw-ups in making both astaxanthin and DMF mouse chows ended up with study data that didn’t measure the full lifespan impacts of activating transcription factor Nrf2. I’ll assert that such faulty data may have deviated this second study by downplaying Nrf2 activation’s impact on aging, chronic disease, and rejuvenation.

Sponsors may be less likely to be presented sulforaphane and other Nrf2 activator candidates for future aging and chronic disease studies as this first study suggests, thinking that these have already been studied in mammals. Well, maybe these compounds haven’t been accurately studied. There’s no effective way to fix a rodent study’s missing DMF Nrf2 data and faulty astaxanthin Nrf2 data to train an epigenetic clock in this second study.

I could be wrong about this second study using faulty astaxanthin Nrf2 data. It was cited as Reference 27 in the Introduction as an ITP study, but not specifically cited in the Method section. I don’t know how findings such as one of Nrf2’s target genes (“Remarkably, one of the top genes positively associated with maximum lifespan and negatively associated with chronological age and expected mortality was Gpx1, encoding the selenoprotein glutathione peroxidase 1″) and a Nrf2 specific pathway (Phase II) (“Pathways positively associated with lifespan and negatively with mortality, both before and after adjustment for age, included..xenobiotic metabolism..”) were made without Reference 27. Neither of the above studies has been peer reviewed yet.


The third phase of reversing aging and immunosenescent trends

Here’s a 2025 interview with Dr. Greg Fahy:

“We found that we could statistically demonstrate thymic regeneration morphologically on single individuals at single time points. MRI changes really are detecting shifts from the fatty tissue infiltration state of the involuted thymus to the regenerated thymus with functional thymic epithelial cells.

When you go through puberty your thymus involutes so you don’t have much left even when you’re 40. Essentially the process consists of loss of functional thymic mass and replacement of that functional thymic mass with adipose tissue, that’s what thymic involution is. It continues throughout life, but you retain a small amount of functional thymic mass all the way out to the age of 107.

The function of the thymus is to essentially manufacture half of your immune system. You have precursor cells arise from the bone marrow. They either go into the meiotic lineage and turn into the innate immune system, or you have the lymphocytic cells for what turns into T cells that enter the thymus and are educated in the thymus to grow up into newborn T cells and they’re released into the bloodstream.

The thymus has two jobs. It manufactures these lovely T cells without which you die but it also has a secondary finishing school. In the thymus cortex you manufacture all these lovely T cells but in the thymus medulla the T cells go to the medulla and if they don’t pass the second examination that they have to pass before they release into the body they’re all killed off. That second examination is: Do you reject self? As we get older, the thymus weakens in both the functions of making the T cells and screening out the ones that attack self. It stands to reason as we get older and the thymus’ influence wanes, we’re going to get more autoimmune disorders.

It took people a while to catch on to the fact that this involution problem is really a significant issue because the T cells that you made when you were 12, and even 20 and 40, they’re probably lasting until you’re 60. But at some point they don’t get replaced as fast as they’re going out of existence, and then your immune system goes off the cliff. Between the ages of 62 and 78 you lose 98% of your ability to recognize foreign antigens, and you still have a lot of capacity left.

We had nine guys in the first trial. Second trial we had 18 men 6 women and 2 controls that happen to be contemporaneous with that group. We have some more controls now that are either finished or or nearing completion. The second population was older than the first population by about nine years, but based on the epigenetic clocks that we looked at, they were starting off biologically younger.

On this last data analysis for Triim XA we looked at 21 different aging clocks. One aspect of the noise that we’re talking about is that biological aging as measured by some of these clocks is circadian. If you measure your age at 4:00 a.m. versus 11:00 a.m. you’re going to get a different result. It’s dynamic and there’s a trend and over time you change in a certain direction, but over any short period of time you can bounce around a little bit. The clocks predict your probability of cognitive dysfunction, they predict your probability of having impairments in your daily life, and they also predict your mortality.

We’re pretty much wrapping up that second clinical trial and going into the third. As we look at more data we understand more and more things and we see more and more things that we previously were not aware of. We began to look at a phenomena that may be responsible for limiting the magnitude of responses that we’re seeing limiting the aging reversal.

Triim-XD which is the next flavor of Triim-X is going to be looking at shifting biochemical pathways in such a way that it optimizes effects of these three medications that we’re giving people [human growth hormone, DHEA, and metformin] and prevents contradictions between them and prevents side effects of each one of these things. That’s about all I can tell you right now.”


Charts regarding the discussed item of how long effects may last are covered in The next phase of reversing aging and immunosenescent trends which was the last time I curated this research effort.


Practice what you preach, or shut up

A 2025 review subject was sulforaphane and brain health. This paper was the latest in a sequence where the retired lead author self-aggrandized his career by citing previous research.

He apparently doesn’t personally do what these research findings suggest people do. The lead author is a few weeks older than I am, and has completely white hair per an interview (Week 34 comments). I’ve had dark hair growing in (last week a barber said my dark hair was 90%) since Week 8 of eating broccoli sprouts every day, which is a side effect of ameliorating system-wide inflammation and oxidative stress.

If the lead author followed up with what his research investigated, he’d have dark hair, too. Unpigmented white hair and colored hair are both results of epigenetics.

Contrast this lack of personal follow-through of research findings with Dr. Goodenowe’s protocol where he compared extremely detailed personal brain measurements at 17 months and again at 31 months. He believes enough in his research findings to personally act on them, and demonstrate to others how personal agency can enhance a person’s life.

It’s every human’s choice whether or not we take responsibility for our own one precious life. I’ve read and curated on this blog many of this paper’s references. Five years ago for example:

So do more with their information than just read.

https://www.mdpi.com/2072-6643/17/8/1353 “Sulforaphane and Brain Health: From Pathways of Action to Effects on Specific Disorders”

2025 α-ketoglutarate research

I haven’t mentioned α-ketoglutarate for a while, although I’ve taken it twice a day for several years. Here are four 2025 papers on α-ketoglutarate, starting with a review of its role in bone health:

“α-Ketoglutarate (α-KG) serves as a pivotal intermediate in various metabolic pathways in mammals, significantly contributing to cellular energy metabolism, amino acid metabolism, and other physiological processes. α-KG may be a therapeutic target for a variety of bone-related diseases, such as osteoporosis, osteoarthritis, and rheumatoid arthritis, because of its role in maintaining metabolic balance of bone.

α-KG, as a rate-determining mitochondrial intermediate, is crucial in cell energy metabolism because it connects intracellular carbon and nitrogen metabolism between isocitrate and succinyl coenzyme A. Additionally, α-KG is closely involved in the amino acid cycle. As a precursor of amino acids such as glutamine and glutamic acid, α-KG plays a direct role in energy production and a wide range of cellular chemical reactions. α-KG provides an energy source, stimulating protein synthesis, inhibiting protein degradation in muscle, and serving as a significant metabolic fuel for gastrointestinal cells.

α-KG promotes osteogenic differentiation of stem cells, increases activity of osteoblasts to promote osteogenesis, and inhibits bone resorption activity of osteoclasts. α-KG in articular cartilage promotes differentiation and maturation of chondrocytes and formation of a cartilage matrix. The protective effect of α-KG on bone has practical value in treatment of abnormal bone loss symptoms in various bone tissue diseases.”

https://www.sciengine.com/ABBS/doi/10.3724/abbs.2025020 “Essential role of the metabolite α-ketoglutarate in bone tissue and bone-related diseases”


A rodent study explored adding α-KG to osteoarthritis treatment:

“Mesenchymal stem cell (MSC) therapy represents a promising treatment strategy for osteoarthritis (OA). Nevertheless, the therapeutic efficacy of MSCs may be attenuated under conditions of cellular senescence or when the available clinical quantity is insufficient. α-Ketoglutarate (AKG) exerts beneficial effects on skeletal tissues and activity of stem cells. The present study was designed to explore the potential of AKG in augmenting viability of MSCs and the potential of their combined utilization in treatment of OA.

AKG plays a crucial role in multiple biological processes. It is involved in regulating stem cell differentiation, exerts anti-apoptotic effects, modulates the body’s immune and inflammatory responses, contributes to muscle and bone development, and is essential for maintaining stability of the cartilage matrix.

Platelet-rich plasma (PRP) has been demonstrated to have protective effects on chondrocytes and can effectively repair damaged cartilage in OA. However, PRP has intractable problems in terms of product quality control and allogeneic application, and its long-term therapeutic effect gradually weakens.

Combining AKG’s regulation of cellular metabolism with the multi-directional differentiation and immunomodulatory functions of MSCs is likely to generate a synergistic effect. This combined treatment modality targets the complex pathological processes of OA, including cartilage damage, inflammatory responses, and extracellular matrix imbalance, in a more comprehensive manner than a single therapy.”

https://www.sciencedirect.com/science/article/pii/S2707368825000032 “The repair effect of α-ketoglutarate combined with mesenchymal stem cells on osteoarthritis via the hedgehog protein pathway”


A rodent study investigated whether α-KG has a role in determining frailty:

“Frailty is an age-related geriatric syndrome, for which the mechanisms remain largely unknown. We performed a longitudinal study of aging female (n = 40) and male (n = 47) C57BL/6NIA mice, measured frailty index, and derived metabolomics data from plasma samples.

We find that frailty related metabolites are enriched for amino acid metabolism and metabolism of cofactors and vitamins, include ergothioneine, tryptophan, and alpha-ketoglutarate, and present sex dimorphism. We identify B vitamin metabolism related flavin adenine dinucleotide and pyridoxate as female-specific frailty biomarkers, and lipid metabolism related sphingomyelins, glycerophosphoethanolamine and glycerophosphocholine as male-specific frailty biomarkers.

We were interested to observe whether metabolite abundance at any specific timepoint was associated with frailty at a future timepoint. Unfortunately, we didn’t observe any metabolites that showed an overall significant association with future FI (FIf) or future devFI (devFIf). When focusing only on the abundance of metabolites at the baseline time point (∼400 days), we found a single metabolite, alpha-ketoglutarate, was negatively associated with both FIf and devFIf.”

https://www.biorxiv.org/content/10.1101/2025.01.22.634160v1.full “Metabolomics biomarkers of frailty: a longitudinal study of aging female and male mice”


Wrapping up with a rodent study adding α-KG to exercise for its effects on depression and learning:

“aKG acts as a prophylactic and antidepressant to effectively counteract social avoidance behaviors by modulating BDNF levels in the hippocampus and nucleus accumbens. Exercise increases aKG levels in the circulation.

In mice, aKG supplementation prolongs lifespan and reduces aging-associated frailty. aKG supplementation also reverses aging in humans as measured by DNA methylation patterns.

aKG functions as a co-factor for epigenetic enzymes. Changes in the intracellular αKG/succinate ratio regulates chromatin modifications, including H3K27me3 and ten-eleven translocation (Tet)-dependent DNA demethylation. The ability of aKG to influence epigenetic status of cells may explain both its prophylactic and anti-depressant effects since transcriptional dysregulation and aberrant epigenetic regulation are unifying themes in psychiatric disorders. This may also explain its ability to differentially regulate BDNF expression in the hippocampus and NAc.

If exercise mediates its effects through aKG, aKG may be a pivotal component of an exercise pill along with lactate and BHB that can serve as both a prophylactic and antidepressant treatment for depression.”

https://www.sciencedirect.com/science/article/pii/S266717432500031X “α-ketoglutarate (aKG) is a circulatory exercise factor that promotes learning and memory recall and has antidepressant properties


Vitamin K2 and your brain

A 2025 review linked Vitamin K2‘s effects on vascular health with cognitive function:

“Cardiovascular disease (CVD) is negatively correlated with cognitive health. Arterial stiffness, in particular, appears to be a critical factor in the functional and structural brain changes associated with aging. We review the association between vitamin K and cerebral function, discussing novel developments regarding its therapeutic role in arterial stiffness and cognitive health.

Among the non-invasive measures of vascular stiffness, pulse wave velocity (PWV) is considered the gold standard. PWV measures arterial stiffness along the entire aortic pathway, providing a reliable, feasible, and accurate assessment of vascular health. Arterial stiffness, as measured by PWV, is negatively associated with total brain volume, brain atrophy, and cognitive function. Pathogenic mechanisms responsible for vascular stiffness recently shifted from collagen and elastin to the differentiation of vascular smooth muscle cells to osteoblastic phenotype, which is triggered by oxidative stress and inflammation, membrane mechanotransduction, lipid metabolism, genetic factors, and epigenetics.

Vitamin K-dependent proteins (VKDPs) rely on vitamin K to undergo γ-glutamylcarboxylation, a modification essential for their biological activity. This family of proteins includes hepatic VKDPs such as prothrombin, FVII, FIX, and FX, protein S and protein C as well as extrahepatic VKDPs such as matrix Gla-protein (MGP), which is involved in inhibiting vascular calcification, and osteocalcin, which plays a role in bone mineralization.

Structural differences between K1 and K2 influence their bioavailability, absorption, bioactivity, and distribution within tissues. Compared to vitamin K1, the K2 subtype menaquinone-7 (MK-7) has a significantly longer half-life, accumulates more effectively in blood, and exhibits greater biological activity, particularly in facilitating the carboxylation of extrahepatic VKDPs. Circulating dephosphorylated, uncarboxylated Matrix Gla protein (dp-ucMGP), a marker of extrahepatic vitamin K deficiency, could represent a novel therapeutic target for mitigating both arterial stiffness and cognitive decline.

Vascular calcification and arterial stiffness may represent pathophysiological mechanisms underlying the onset and progression of cognitive decline. Vitamin K deficiency is a key determinant of arterial health and, by extension, may influence cognitive function in the elderly.

To elucidate potential therapeutic benefits of MK-7 supplementation on cognitive function, future randomized controlled trials (RCTs) are needed. These trials should focus on using optimal dosages (>500 μg/day), ensuring long follow-up periods, and utilizing the most bioactive form of vitamin K (MK-7).”

https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2024.1527535/full “The role of vitamin K2 in cognitive impairment: linking vascular health to brain health”


A coauthor Dr. Katarzyna Maresz took time on her weekend to answer a few questions:

1. Regarding the second paper of Part 2 of Vitamin K2 – What can it do?:

Hello Dr. Maresz. Did this trial ever happen? “Effects of Combined Vitamin K2 and Vitamin D3 Supplementation on Na[18F]F PET/MRI in Patients with Carotid Artery Disease: The INTRICATE Rationale and Trial Design” I haven’t seen a followup mention of it since 2021.

“Hello. The study never started. The capsules were produced for the study, but the research center experienced delays. Unfortunately, I’m afraid it won’t proceed. Regarding studies on aortic stenosis and vitamin K2, BASIC II has been completed, and the data from this pilot study are currently under analysis. (https://pubmed.ncbi.nlm.nih.gov/29561783/). There is also published study with K1: https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.116.027011

2. Thank you! In your recent review of cognitive function and K2 (above), what influenced the heuristic that a >500 mcg K2 dose should be pursued in future RCTs?

“The optimal vitamin K dosage depends on the target population. Research in kidney patients has shown that 460 mcg daily was insufficient, that is why have hypothesis that at least 500 mcg should be used. The ongoing VIKIPEDIA study is using 1,000 mcg daily in peritoneal dialysis patients. In healthy young individuals, 180-360 mcg was effective in improving vitamin K status (British Journal of Nutrition (2012), 108, 1652–1657) . However, a one-year clinical study found that 180 mcg daily was sufficient for women but not for men. Additionally, older adults and individuals with metabolic disorders may require higher doses for optimal benefits. So it is pretty complicated situation. We do not have good marker of extrahepatic K status. dp-ucMGP seems to be valuable from CV perspective.”

3. Regarding Fat-soluble vitamin competition:

Thank you again Dr. Maresz! Would any consideration be given to dosing K2 separately from dosing another fat-soluble vitamin? A 2015 in vitro study found that vitamins D, A, and E outcompeted K1 intake when simultaneously dosed. I inferred from the one capsule of D3-K2 produced for the canceled trial that isn’t that much of a problem with K2?

“You are right, the key findings suggest that vitamin D, E, and K share common absorption pathways, leading to competitive interactions during uptake. However, I’m afraid we do not have human data. The majority of studies have focused on vitamin K2 alone. Recent research combining K2 and D3 showed an improvement in vitamin K status. Example: https://pubmed.ncbi.nlm.nih.gov/35465686/ or increase in D level: https://pubmed.ncbi.nlm.nih.gov/39861434/. We do not know if VKDP activation or absorption of D would be more effective if K2 were not supplemented with D3 at the same time. Unfortunately, I doubt anyone will fund such a study, as clinical trials are very expensive. In vitro data will always raise questions regarding their relevance to human physiology. In my opinion, for patients to fully benefit from optimal vitamin K status, vitamin D levels should also be optimized, as both have synergistic effects.”

Epigenetic clock analysis of a clinical trial

A 2025 paper performed post-hoc epigenetic clock analyses of a supplement and exercise clinical trial completed earlier this decade:

“We report results of a post hoc analysis among 777 participants of the DO-HEALTH trial on the effect of vitamin D (2,000 IU per day) and/or omega-3 (1 g (330 mg EPA plus 660 mg DHA from marine algae) per day) and/or a home exercise program (a strength-training exercise program performed for 30 min three times per week) on four next-generation DNA methylation (DNAm) measures of biological aging (PhenoAge, GrimAge, GrimAge2 and DunedinPACE) over 3 years. Omega-3 alone slowed the DNAm clocks PhenoAge, GrimAge2 and DunedinPACE, and all three treatments had additive benefits on PhenoAge.

Inclusion criteria were age 70 years and older, living at home, having no major health events (no cancer or myocardial infarction) in the 5 years before enrollment, having sufficient mobility to visit the study centers without help and having good cognitive function with a Mini-Mental State Examination score of at least 24. 777 provided consent for these analyses and had samples available after the application of the exclusion criteria. This group of individuals formed our analysis sample, which had the following characteristics: 59% were women; the mean age at baseline was 75 years; 30% had 25-hydroxyvitamin D (25(OH)D) levels of <20 ng ml−1; 53% were healthy agers as defined in the Nurses’ Health Study (free of major chronic diseases, disabilities, cognitive impairments and mental health limitations); and 88% were physically active (29% were active one to three times per week, and 59% were active more than three times per week). The Swiss participant subgroup represents a healthier and more active subgroup within the total DO-HEALTH population.

Overall, from baseline to year 3, standardized effects ranged from 0.16 to 0.32 units (2.9–3.8 months). In summary, our trial indicates a small protective effect of omega-3 treatment on slowing biological aging over 3 years across several clocks, with an additive protective effect of omega-3, vitamin D, and exercise based on PhenoAge.”

https://www.nature.com/articles/s43587-024-00793-y “Individual and additive effects of vitamin D, omega-3 and exercise on DNA methylation clocks of biological aging in older adults from the DO-HEALTH trial”

These epigenetic clock measurements of a subset of trial subjects was interesting, although I didn’t find it particularly relevant to what I do. I take twice as much Vitamin D and omega-3s everyday, do resistance exercises once or twice a week whenever I’ve recovered from the previous session, walk a few miles on the beach if the weather is nice, and other things.

I don’t bother with epigenetic clock measurements anymore because the free one (PhenoAge) is too variable to be personally accurate. For other clocks, it would be meaningless if all I got was a 2-3 month improvement over a three year period like this trial. Studies usually find that the most deficient subjects at the beginning are the ones that show the greatest improvements with effective treatments. Unhealthiness on any epigenetic clock parameter probably wouldn’t be my starting point, so I may not show even a one-month improvement over three years.


Dr. Goodenowe offered his opinion on the paper:

“DHA is a polyunsaturated fatty acid that is essential for maintaining youthful fluidity of the body’s membranes. While our bodies can make DHA from the essential omega-3 dietary fatty acid, as we get older, our ability to make DHA decreases and oxidative stress on our bodies increases. These two factors contribute to our membranes becoming stiffer and less pliable as we age, in other words, ‘older.’

Because getting older and losing function appear to go hand in hand, we equate aging with a loss of function. As such, we think that aging causes this loss of function, like a disease. Instead, the opposite is true, and it’s the loss of function that causes aging. To slow aging you need to focus on maintaining function.”

https://www.prevention.com/health/a63850396/vitamin-exercise-boost-longeivty-study/ “Scientists Find Taking This Vitamin Boosts Longevity, Add Years to Your Life”

Prevention magazine’s editors need to better proof their writers’ work before it gets published. Unlike the headline, the trial had nothing to do with adding years to human lifespan.

Coffee compound effects

Three papers continue Polyphenol Nrf2 activators themes starting with a 2025 review of chlorogenic acid:

“Chlorogenic acid may comprise between 70 and 350 mg per cup of coffee. Chlorogenic acid can reduce reactive oxygen species (ROS) levels via the upregulation of antioxidant enzymes, decreasing oxidative stress/damage due to the action of adaptive hormetic mechanisms. There is also a substantial literature of hormetic dose responses for metabolites of chlorogenic acid, such as caffeic acid and ferulic acid.

Chlorogenic acid-induced hormetic biphasic dose responses in a spectrum of experimental designs:

  1. Responses to direct exposures in a range of cell types;
  2. Preconditioning experiments in which a prior dose of chlorogenic acid protected against a subsequent stressor agent;
  3. Studies that included direct exposure, showing hormesis dose responses and then selecting the optimal hormetic dosage as a preconditioning treatment to protect against a subsequent exposure to a toxic agent; and
  4. A mixed group of experiments in which preconditioning was conducted, including several neuronal cellular models, all showing protection against the subsequent exposure to the toxic agent.

However, in the context of translating experimental data to clinical relevance, the concentrations employed in the majority of the in vitro studies with chlorogenic acid far exceeded transitory peak levels, even in heavy coffee drinkers (i.e., approximately 3 μM). In addition to the use of unrealistically high chlorogenic acid concentrations, exposures were prolonged, ranging from 1 to 3 days. These studies are of limited relevance to humans, a similar concern raised by other researchers involved with polyphenol research.


The present paper has framed the hypothesis that key coffee constituents, such as chlorogenic acid, show hormetic effects in a range of cell types and endpoints. Chlorogenic acid may affect some of the health benefits of coffee drinking via its role in GI tract health and beneficial brain-gut interaction.”

https://www.sciencedirect.com/science/article/abs/pii/S0009279724004897 “Do the hormetic effects of chlorogenic acid mediate some of the beneficial effects of coffee?” (not freely available) Thanks to Dr. Evgenios Agathokleous for providing copies of this and the following paper.


A 2024 review by the same research group was on hormetic effects of caffeic acid:

“Caffeic acid is a polyphenol present in numerous fruits and vegetables, especially in coffee. Diets contain about 5–10 to 50 milligrams per day of caffeic acid while coffee ingestion provides about another 250–600 milligrams per day. For the moderate to heavy coffee drinker this would result in an ingestion of about 600–1000 milligrams of caffeic acid from food and coffee consumption.

The present paper evaluates whether caffeic acid may act as an hormetic agent, mediating its chemoprotective effects as has been shown for related agents, such as rosmarinic acid, ferulic acid, and chlorogenic acid. Caffeic acid protective effects were mediated via the upregulation of a series of antioxidant enzymes related to activation of Nrf2.

Caffeic acid enhanced the lifespan of C. elegans along with similar observations for rosmarinic acid that can be hydrolyzed to caffeic acid. Several hundred plant-based agents can enhance lifespan in experimental models such as C. elegans, and there is a competition to find the most effective agents with potential commercial applications.

Hormetic effects typically show a 30 to 60% stimulation above control. This is far below the 2 to 3-fold greater than control detection limit for statistical significance based on human variability/bioplasticity and are often reported as false negatives.

A weight-of-evidence approach was proposed based on multiple in vivo and in vitro test results to derive a study design strategy to increase detection of hormetic effects within the clinical trial framework. Such research should explore hormetic based interactions linking protective catabolic-based adaptive responses with activation and regulation of anabolic mediated hormetic growth effects.”

https://www.tandfonline.com/doi/full/10.1080/19390211.2024.2410776 “Caffeic Acid: Numerous Chemoprotective Effects are Mediated via Hormesis” (not freely available)


A 2024 review provided an overall picture of coffee compounds’ cardiometabolic effects:

“This review provides a comprehensive synthesis of longitudinal observational and interventional studies on the cardiometabolic effects of coffee consumption.

  • Findings indicate that while coffee may cause short-term increases in blood pressure, it does not contribute to long-term hypertension risk.
  • There is limited evidence indicating that coffee intake might reduce the risk of metabolic syndrome and non-alcoholic fatty liver disease.
  • Coffee consumption is consistently linked with reduced risks of type 2 diabetes (T2D) and chronic kidney disease (CKD), showing dose-response relationships.
  • The relationship between coffee and cardiovascular disease is complex, showing potential stroke prevention benefits but ambiguous effects on coronary heart disease.
  • Moderate coffee consumption, typically ranging from 1 to 5 cups per day, is linked to a reduced risk of heart failure, while its impact on atrial fibrillation remains inconclusive. Coffee consumption is associated with a lower risk of all-cause mortality, following a U-shaped pattern, with the largest risk reduction observed at moderate consumption levels.
  • Except for T2D and CKD, Mendelian randomization studies do not robustly support a causal link between coffee consumption and adverse cardiometabolic outcomes.

Potential beneficial effects of coffee on cardiometabolic health are consistent across age, sex, geographical regions, and coffee subtypes and are multi-dimensional, involving antioxidative, anti-inflammatory, lipid-modulating, insulin-sensitizing, and thermogenic effects. Based on its beneficial effects on cardiometabolic health and fundamental biological processes involved in aging, moderate coffee consumption has the potential to contribute to extending healthspan and increasing longevity.”

https://pmc.ncbi.nlm.nih.gov/articles/PMC11493900 “Coffee consumption and cardiometabolic health: a comprehensive review of the evidence”


Nrf2 regulation

This 2025 review explored what’s known so far about Nrf2 post-translational regulators:

“Nrf2 is controlled at multiple levels, including epigenetic, transcriptional, translational, and post-translational. The focus of this review is on proteins that control Nrf2 at the post-translational level because in normal cells they are of preeminent importance.

We outline mechanisms by which multiple E3 ubiquitin ligases act to repress Nrf2 expression, how derepression of Nrf2 (and induction of its target genes) by oxidative stressors occurs, and why tissue injury and endoplasmic reticulum stress downregulate Nrf2. This update also explains how Nrf2 is embedded in thiol biochemistry, and outlines signaling pathways and endogenous signaling molecules that control its activity.

Nrf2 not only positively controls the basal and/or inducible expression of a substantial number of genes in all tissues but also downregulates many genes. Estimates of the number of antioxidant/electrophile-responsive element (ARE/EpRE)-driven genes that are positively regulated by Nrf2 vary from several hundred to >2000 depending on the experimental method, species, cell type, physiology, age, sex, diet, and the magnitude of the change that is deemed to be significant.

Induction of ARE/EpRE-driven genes allows adaptation to oxidative, electrophilic, and inflammatory stress. Nrf2 positively regulates clusters of genes encoding proteins classed broadly as antioxidant, drug-, heme-, and iron-metabolizing, pentose phosphate pathway, NADPH-generating, and autophagy-related, as well as fatty acid oxidation enzymes, lipases, transcription factors, and Keap1.

Genes that are negatively regulated by Nrf2 include those encoding the cytokines IL-1β and IL-6, myosin light-chain kinase (MYLK), and NADPH oxidase 4 (NOX4). Nrf2 also regulates some microRNAs, which represents another mechanism by which Nrf2 can downregulate the expression of genes such as those encoding collagens 1A2, 3A1, and 5A1, heat shock protein 47, fibronectin, and elastin. In addition, several lipogenesis-related genes such as fatty acid synthase 1 (FASN1) and acetyl-CoA carboxylase 1 (ACC1), stearoyl-CoA desaturase (SCD1), and fatty acid elongase 6 (ELOVL6) are downregulated upon Nrf2 activation, particularly under conditions of lipid overload. Given that lipogenesis is a highly NADPH-consuming process, it seems that Nrf2 activation redirects NADPH consumption from lipid synthesis towards redox reactions, although the mechanisms underlying the negative regulation of these genes are incompletely understood.

de novo synthesized Nrf2 upon Keap1 inactivation enables a rapid increase of levels of the transcription factor in response to metabolic changes and environmental challenges, allowing cells to adapt and restore homeostasis.”

https://www.cell.com/trends/biochemical-sciences/fulltext/S0968-0004(24)00282-2 “Regulating Nrf2 activity: ubiquitin ligases and signaling molecules in redox homeostasis”

This review’s primary audience is other researchers, and it ended with 15 outstanding items that Nrf2 research hasn’t yet adequately addressed.