Discovering a new NAD+ precursor

A 2025 rodent study investigated dynamics of organ and circulating nicotinamide:

“Liver-derived circulating nicotinamide from nicotinamide adenine dinucleotide (NAD+) catabolism primarily feeds systemic organs for NAD+ synthesis. We surprisingly found that, despite blunted hepatic NAD+ and nicotinamide production in liver-specific nicotinamide nucleotide adenylyltransferase 1 (NMNAT1) deletion mice (liver-specific knockout [LKO]), circulating nicotinamide and extra-hepatic organs’ NAD+ are unaffected.

Metabolomics reveals a massive accumulation of a novel molecule in the LKO liver, which we identify as nicotinic acid riboside (NaR). The liver releases NaR to the bloodstream, and kidneys take up NaR to synthesize NAD+ through nicotinamide riboside kinase 1 (NRK1) and replenish circulating nicotinamide.

Serum NaR levels decline with aging, whereas oral NaR supplementation in aged mice boosts serum nicotinamide and multi-organ NAD+, including kidneys, and reduces kidney inflammation and albuminuria. The liver-kidney axis maintains systemic NAD+ homeostasis via circulating NaR, and NaR supplement ameliorates aging-associated NAD+ decline and kidney dysfunction.

While this study provides evidence of hepatic production and renal consumption of NaR for NAD+ homeostasis in mice, future human works are warranted to confirm these findings. In addition, genetic studies will be necessary to fully understand NaR metabolism at cellular and organismal levels.

While this study shows the oral availability of NaR and its effect on systemic NAD+ metabolism in mice, human studies testing NaR safety, oral availability, pharmacokinetics, and pharmacodynamics should be performed to test potential clinical usage of NaR supplements. Additionally, future studies are needed to investigate physiological significance of NT5C2-mediated hepatic production of NaR in healthy mice and identify NaR transporter(s).”

https://www.cell.com/cell-metabolism/abstract/S1550-4131(25)00217-7 “Nicotinic acid riboside maintains NAD+ homeostasis and ameliorates aging-associated NAD+ decline” (not freely available) Thanks to Dr. Dorota Skowronska-Krawczyk for providing a copy.


An elaborating commentary was published along with this study:

“Nicotinamide (NAM), nicotinamide riboside (NR), nicotinic acid (NA), and NAR are the salvageable precursors that feed into production of nicotinamide mononucleotide (NMN) and nicotinic acid mononucleotide (NAMN) to regenerate NAD coenzymes. NAMN is at an interesting juncture in NAD metabolism because it is formed in de novo synthesis and in salvage synthesis from both NA and NAR.

Song and coworkers did not specifically set out to determine endogenous sources of NR and/or NAR. Rather, they wanted to see what would happen when they deleted the major Nmnat isozyme, Nmnat1, in liver.

With depression of hepatic NAD+, they saw elevation of liver NMN and NAMN and discovered a huge increase in hepatic and circulating NAR. By viral knockdown, the step of conversion of accumulated NAMN to NAR was found to be catalyzed by a 5′ – nucleotidase encoded by the Nt5c2 gene, and the major tissue receiving the NAR was found to be the kidney.

Further, they showed that levels of NAR decline in aging while provision of supplementary NAR supports a newfound ability of the mouse kidney to circulate NAM. Of potential translational significance, supplementary NAR also supported mouse kidney function in aging.”

https://www.brennerlab.net/curriculumvitae/ “The NARly side of whole-body NAD homeostasis” (*pdf at page bottom)

A Nrf2 treatment for ALS?

A 2025 rodent in vivo / human cell ex vivo study investigated effects of a Nrf2 activator on ALS rodent models and ALS human nervous system cells:

“M102 is a central nervous system (CNS) penetrant small molecule electrophile which activates in vivo the NF-E2 p45-related factor 2-antioxidant response element (NRF2-ARE) pathway, as well as transcription of heat-shock element (HSE) associated genes. Apart from the recent promising emergence of tofersen as a disease modifying therapy for the 2% of ALS patients who harbor mutations in the SOD1 gene, other approved drugs have only marginal effects on life expectancy (riluzole) or indices of disease progression (edaravone).

Data from disease model systems and from human biosamples provide strong evidence for a role of redox imbalance, inflammation, mitochondrial dysfunction, and altered proteostasis, including autophagy and mitophagy, as four key drivers in the pathobiology of ALS. We demonstrate that M102 is a dual activator of NRF2 and HSF1 transcription factor pathways, two upstream master regulators of neuroprotective mechanisms, with the potential to modulate all four of these key drivers of neurodegeneration and with excellent penetration across the blood brain barrier.

Stress response of the KEAP1-Nrf2-ARE system is stronger in astrocytes compared to neurons. A body of evidence from in vitro and in vivo model systems and from post-mortem CNS tissue from ALS patients has indicated that the NRF2 response is impaired in ALS, and has also been shown to decline with age.

HSF1 is a stress-inducible transcription factor that is the key driver for expression of multiple heat shock proteins which act as chaperones responsible for correct folding of newly synthesized proteins, refolding of denatured proteins, and prevention of aggregation of misfolded proteins. However, to date, many small molecule activators of HSF-1 have shown undesirable properties e.g. by acting as Hsp90 inhibitors or by exerting direct proteotoxic effects.

M102 (S-apomorphine hydrochloride hemihydrate) is a proprietary new chemical entity (NCE) and the S-enantiomer of the marketed R-apomorphine (Apokyn®; pure R-enantiomer). The R-enantiomer is a dopamine agonist administered subcutaneously for management of advanced Parkinson’s disease. M102 is a very weak dopamine antagonist and does not show the adverse effects associated with dopamine agonism.

M102 treatment rescues motor neuron (MN) survival in co-cultures with C9, SOD1 and sporadic ALS patient-derived astrocytes. Other NRF2 activators have been investigated in clinical trials or have been approved for medical use. These include dimethylfumarate (DMF) (Tecfidera®, Biogen) and omaveloxolone (Reata, Biogen).

  • DMF was originally approved for the treatment of psoriasis (Fumaderm®) and was later repurposed for the treatment of relapsing-remitting multiple sclerosis (Tecfidera®). A phase 2 trial of DMF in ALS provided Class 1 evidence of safety at a dose of 480 mg/day and lack of disease-modifying efficacy. DMF treatment is associated with dose-limiting lymphopenia and flushing (Tecfidera® Prescribing Information).
  • Omaveloxolone (Skyclarys®) is a potent NRF2 activator that has been approved by the FDA and EMA for the treatment of Friedreich’s ataxia. By activating the NRF2 pathway, omaveloxolone ameliorates oxidative stress and improves mitochondrial function. As a potent NRF2 activator, omaveloxolone exhibited significant liver toxicity with elevated AST/ALT levels in 37% of patients exposed to a dose of 150 mg.
  • Toxicity has also been reported with other potent NRF2 activators, such as bardoxolone methyl (EC50: 53 nM) which showed significant heart, liver, and renal toxicity in humans.

In contrast, our preclinical toxicological studies indicate that M102 has a much higher safety margin in relation to liver toxicity. M102 has the potential to modulate multiple key drivers of neurodegeneration, increasing the chances of achieving impactful neuroprotection and disease modifying effects in ALS.

This comprehensive package of preclinical efficacy data across two mouse models as well as patient-derived astrocyte toxicity assays, provides a strong rationale for clinical evaluation of M102 in ALS patients. Combined with the development of target engagement biomarkers and the completed preclinical toxicology package, a clear translational pathway to testing in ALS patients has been developed.”

https://molecularneurodegeneration.biomedcentral.com/articles/10.1186/s13024-025-00908-y “M102 activates both NRF2 and HSF1 transcription factor pathways and is neuroprotective in cell and animal models of amyotrophic lateral sclerosis”


Combining exercise with sulforaphane

A 2025 clinical trial with old people compared NRF2 effects of acute exercise with pre- and post-exercise sulforaphane treatment:

“This study tested the hypothesis that combining acute exercise (in vivo stimulus) with ex vivo sulforaphane (SFN) treatment would induce greater NRF2 activation and signaling in older adults compared to either treatment alone. This approach was used to bypass the potential issue of inter-individual variability in metabolism and bioavailability of SFN supplementation through oral consumption and thereby provide more rigorous biological control to establish mechanistic feasibility.

Twenty-five older adults (12 men, 13 women; mean age: 67 ± 5 years) performed 30-min cycling exercise. Blood was drawn before and immediately after exercise to isolate peripheral blood mononuclear cells (PBMCs) and incubate with and without SFN (5 μM) treatment.

Acute exercise induced modest transcriptional changes across the four tested transcripts compared to the robust upregulation elicited by SFN. This disparity was notable given the comparable NRF2/ARE binding activity observed between EX and SFN.

Near-significant trends were observed for EX in heme oxygenase-1 (HO-1), NAD(P)H quinone oxidoreductase 1 (NQO1), and glutathione reductase (GR) (after Bonferroni correction), while glutamate-cysteine ligase catalytic subunit (GCLC) was not induced by EX. In contrast, SFN alone robustly induced expression of NQO1, HO-1, GR, and GCLC.

We had chosen 5 μM as the dose based on pilot data from our laboratory and existing literature from in vitro experiments. However, typically, SFN is not combined with another stimulus.

To test this speculation, we ran a post hoc dose–response experiment where we stimulated PBMCs (n = 5) at six different SFN concentrations ranging from 0 to 20 μM (incubated for 5 h) and analyzed responses across the four genes used in the present study. The dose responses displayed hormetic curves for NQO1, GR, and GCLC, with 5 μM eliciting the peak response, suggesting that the lack of difference between SFN and the combined treatment was due to a ceiling effect of the SFN dose. Interestingly, HO-1 displayed a linear/curvilinear response with the maximal observed response at 20 μM.

In future ex vivo studies, a sulforaphane concentration of 1–2 μM in combination with acute exercise is predicted to enhance the expression of these antioxidant genes in the PBMCs of older adults to a greater extent than either treatment alone. Furthermore, lower SFN plasma concentrations are more likely to be achievable with oral supplementation.

To our knowledge, this is the first trial to measure responses to acute exercise combined with sulforaphane stimulation on NRF2 signaling in older men and women. We did not observe any statistically significant differences in any of our outcome variables between men and women.

Our results demonstrate that combining acute exercise with a sulforaphane stimulus elicits a greater response in nuclear NRF2 activity in older adults. While the response in gene expression did not completely mirror the response in NRF2 activation, it is important to note that NRF2 induces hundreds of cytoprotective genes. The four transcripts we measured are among those most commonly used to represent NRF2 signaling but do not capture the full picture. Full transcriptomics in future studies would address this question.”

https://link.springer.com/article/10.1007/s11357-025-01939-5 “Sulforaphane improves exercise-induced NRF2 signaling in older adults: an in vivo-ex vivo approach” (not freely available) Thanks to Dr. Tinna Traustadóttir for providing a copy.


I asked two questions, and will follow up with replies:

  1. Did a second experiment test effects of these subjects eating broccoli sprouts prior to acute exercise? The clinical trial’s NCT04848792 Study Overview section indicated that was the researchers’ intent.
  2. What studies have the data that produced this study’s graphical abstract’s younger vs. older NRF2 response graph?

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.


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.


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.”

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.


Nrf2 activator rankings

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.

PXL_20241223_185836159

Brain restoration with plasmalogens, Part 2

This September 2024 presentation adds data points and concepts to Part 1:

supplementation

  1. “Your brain is dynamically connected to and adaptively responsive to its environment.
  2. You are in control of this environment (nutrition, stimulation, adversity).
  3. Need to measure the environment (lab testing, physiology) and adaptive response to the environment (MRI) to optimize your environment (nutrition, lifestyle) to achieve optimal brain structure, function, health, and longevity.

neurovascular

From a global cortical volume and thickness perspective, 17 months of high dose plasmalogens reversed about 15 years of predicted brain deterioration. 31 months reversed almost 20 years. So you can get more out of life.”

https://drgoodenowe.com/immortal-neurology-building-maintaining-an-immortal-brain/


Dr. Goodenowe also added case studies of two patients:

1. A 50-year-old woman with MS who had been legally blind in one eye for 32 years who regained sight in that eye after eight months of supplementation.

“This is the adaptability of the human brain. Her eye is not actually impaired. What’s impaired is the ability, the adaptability of the brain to the signal of light, to actually start interpreting what that light signal is.”

2. A 61-year-old man with dementia from firefighting work for the U.S. Navy in a toxic environment with head injuries after nine months of supplementation.

“The brain can heal itself is the point of the story. His executive function skills in everyday life are getting better.”

Get a little stress into your life

Two reviews on beneficial effects of mild stress, starting with a 2024 paper coauthored by the lead researcher of Sulforaphane in the Goldilocks zone:

“This paper addresses how long lifespan can be extended via multiple interventions, such as dietary supplements, pharmaceutical agents, caloric restriction, intermittent fasting, exercise, and other activities. This evaluation was framed within the context of hormesis, a biphasic dose response with specific quantitative features describing the limits of biological/phenotypic plasticity for integrative biological endpoints.

Human maximum longevity has remained relatively constant in the 110–120 year time period. Yet, research with C. elegans indicates that hormetic processes increase both average (median/mean) and maximum lifespans. These observations were consistently shown by different research teams using highly diverse stressors but with generally similar experimental methods. Thus, lifespan can be increased in an overall average manner but also within the context of the maximum lifespan potential via hormetic processes, which has not been shown to occur in human population studies.

In multiple experimental and epidemiological contexts, antioxidants have prevented lifespan extension of numerous hormetic agents and blocked human health benefits (e.g., exercise), supporting the hypothesis that oxidative stress is necessary for healthspan improvements and lifespan extension.

Maximum lifespan may be prolonged by extending the lifespan of healthy subjects. Median lifespan would be enhanced by protecting those who are susceptible to genetic/environmental diseases.

Most experimental studies indicate that maximum hormetic lifespan benefits are in the 15 – 25% range when responses are optimized. Human-based benefits could be expected to be less than this maximum range. The issue of hormetic synergies is important to consider, but the available data to date indicates that these benefits are also constrained by limits of biological plasticity.”

https://www.sciencedirect.com/science/article/abs/pii/S1568163723003409 “Hormesis determines lifespan” (not freely available) Thanks to Dr. Evgenios Agathokleous for providing a copy.


A 2023 review of nematode studies was cited three times:

“While stress response pathways are important in allowing organisms to survive acute and chronic stresses, these pathways also contribute to longevity under unstressed conditions. Multiple stress response pathways are required for normal lifespan in wild-type worms, and all of the stress response pathways discussed in this review contribute to the longevity of long-lived mutants.

Four stress response pathways were consistently required for longevity:

  1. The FOXO transcription factor DAF-16-mediated stress response;
  2. The Nrf2 homolog SKN-1-mediated oxidative stress response;
  3. The cytoplasmic unfolded protein response (cyto-UPR); and
  4. The endoplasmic reticulum unfolded protein response (ER-UPR)

are required for normal lifespan, and may contribute to the extended lifespan of long-lived mutants. Developing strategies to activate these pathways, at the right time(s) and in the right tissue(s), may help to promote healthy aging and ameliorate age-onset disease.”

https://www.sciencedirect.com/science/article/pii/S1568163723001009 “Biological resilience and aging: Activation of stress response pathways contributes to lifespan extension”


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Brain restoration with plasmalogens

In this 2023 presentation for a professional audience, Dr. Dayan Goodenowe showed an example of what could be done (in the form of what he personally did at ages 53-54) to restore and augment brain structure and function over a 17-month period by taking plasmalogens and supporting supplements:

https://drgoodenowe.com/recording-of-dr-goodenowes-presentation-from-the-peptide-world-congress-2023-is-now-available/

Follow the video along with its interactive transcript. Restorative / augmentative supplements included:

1. Nutritional Supplementation Strategy

Forms of MRI used to document brain structure and function changes were:

2. Advanced MRI Technologies

Brain volume decreases are the rule for humans beginning at age 40. Dr. Goodenowe documented brain volume increases, which aren’t supposed to happen, but did per the below slide of overall results:

3. Reversing Brain Shrinkage

“From a global cortical volume and thickness perspective, 17 months of high-dose plasmalogens reversed ~15 years of predicted brain deterioration.”


Specific increased adaptations in brain measurements over 17 months included:

  1. Cortical thickness .07/2.51 = +3%.
  2. White matter microstructure fractional anisotropy +8%.
  3. Nucleus accumbens volume +30%.
  4. Dopaminergic striatal terminal fields’ volume +18%.
  5. Cholinergic cortical terminal fields’ volume +10%.
  6. Occipital cortex volume +10%.
  7. Optic chiasm volume +225%.
  8. Nucleus basalis connectivity.
  9. Neurovascular coupling signal controlled by noradrenaline integrity.
  10. Amygdala volume +4% and its connectivity to the insula, indicating ongoing anxiety and emotional stress response.
  11. Parahippocampus volume +7%.
  12. Hippocampus fractional anisotropy +5%.

No changes:

  1. Amygdala connectivity to the ventral lateral prefrontal cortex, the same part of the brain that relates to placebo effect.
  2. Hippocampus connectivity.

Decreased adaptations in brain measurements included:

  1. White matter microstructure radial diffusivity -10%.
  2. Amygdala connectivity to the anterior cingulate cortex to suppress / ignore / deny anxiety response.
  3. Amygdala connectivity to the dorsal lateral prefrontal cortex.
  4. Entorhinal cortex volume -14%.
  5. Hippocampus volume -6%.
  6. Hippocampus mean diffusivity (white matter improved, with more and tighter myelin) -4%.

The other half of this video was a lively and wide-ranging Q&A session.


The referenced 2023 study of 653 adults followed over ten years showed what brain deterioration could be expected with no interventions. Consider these annual volume decrease rates to be a sample of a control group:

etable 3

https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2806488 “Characterization of Brain Volume Changes in Aging Individuals With Normal Cognition Using Serial Magnetic Resonance Imaging”

Also see a different population’s brain shrinkage data in Prevent your brain from shrinking.


The daily plasmalogen precursor doses Dr. Goodenowe took were equivalent to 100 mg softgel/kg, double the maximum dose of 50 mg softgel/kg provided during the 2022 clinical trial of cognitively impaired old people referenced in Plasmalogens Parts 1, 2, and 3.

He mentions taking 5 ml in the morning and 5 ml at night because he used the Prodrome oil products. 1 ml of a Prodrome oil plasmalogen precursor product equals 900 mg of their softgel product.


“My brain is trying to minimize long-term effects of pain/stress by suppressing my memory of it. But this can only go on for so long before it becomes an entrenched state.

I have solved the sustenance side of the equation. I need to work harder to solve the environmental side.”

While I agree that we each have a responsibility to ourselves to create an environment that’s conducive to our health, the above phenomenon isn’t necessarily resolvable by changing an individual’s current environment. My understanding is that long-term effects of pain, stress, and related human experiences are usually symptoms of causes that started much earlier in our lives.

Adjusting one’s present environment may have immediate results, but probably won’t have much therapeutic impact on long-term issues. Early life memories and experiences are where we have to gradually go in order to stop being driven by what happened back then.

See Dr. Arthur Janov’s Primal Therapy for its principles and explanations. I started Primal Therapy at a similar age, 53, and continued for three years.


Continued with Part 2.

Plasmalogens, Part 1

The person who knows the most about this subject is Dayan Goodenowe, PhD. Some recent publications include:

https://www.frontiersin.org/articles/10.3389/fcell.2022.864842/full “Targeted Plasmalogen Supplementation: Effects on Blood Plasmalogens, Oxidative Stress Biomarkers, Cognition, and Mobility in Cognitively Impaired Persons”

https://www.frontiersin.org/articles/10.3389/fcell.2022.866156/full “Brain ethanolamine phospholipids, neuropathology and cognition: A comparative post-mortem analysis of structurally specific plasmalogen and phosphatidyl species”

plasmalogens and cognition


A sample of links freely available at https://drgoodenowe.com/.

1. Presentations to professional groups. Have your mouse ready to click the pause button.

https://drgoodenowe.com/dr-goodenowe-presents-at-the-iagg2023-in-yokohama-japan/ “A rare children’s disease that may be the key to reversing neurological decline in aging”

Includes videos of a treatment’s effects on a child.

https://neomarkgroup.wistia.com/medias/0qln0wy93t “The most influential biomarkers for aging and disease”

Despite the title, a considerable number of studies were presented on prenatal, infant, and early childhood development. He misspoke a few times, so read the slides.

Phenotype is reality. Genotype is possibility. Communications links between different fields are very poorly connected in science.

Peroxisomes are islands. They don’t have DNA like your mitochondria do. Peroxisomal transport issues are important things to understand.

All aging-related cross-sectional analyses are on the rate of decline. You’re declining from a previous well state. Age-matched controls are the most ridiculous thing to do.”


2. I’ll highlight the longest of several interviews because there was plenty of room to expand on points. Maybe the best detailed explanations came as responses to that interviewer challenging with contrasting AD, traumatic brain injury, and cholesterol paradigms. Its transcript is more accurate than a usual YouTube interpretation, but there are still mistakes such as “fossil lipid” vs. phospholipid.

https://www.betterhealthguy.com/episode186 “Plasmalogens with Dr. Dayan Goodenowe, PhD”

“Science is how do you push things to its failure, until you can’t fail it again. We’ve lost that. It’s become more hypothesis proving.

Plasmalogens levels go up for a different reason than people think. The reason why it peaks in our 40s and 50s is because we’ve been myelinating. The white matter of our brain is still increasing. It’s not because we’re making more plasmalogens. It’s because the lake, the reservoir, gets full. What you’re measuring in blood is overflow from the lake. The lower plasmalogens start trickling down in your blood, the bigger drain that’s occurring on that system.

Low plasmalogens don’t just predict dementia in the elderly population. It predicts the rate of decline of that dementia. It predicts the rate of death.

The biggest drivers of plasmalogen manufacturing and the biggest reasons why they decrease with age, or in other circumstances is two things. One, the failure to maintain a fasting state of the human body. The second one is muscle atrophy.

Amyloid has absolutely nothing to do with Alzheimer’s, or dementia. It’s just a bystander on the road watching an accident happen.

Age-related cognitive decline is clearly where plasmalogens have the greatest impact. You’re always going to have mixed pathologies in the brain.

Nutritional availability of plasmalogens is virtually non-existent. As soon as they hit the hydrochloric acid of your stomach, they’re gone. They don’t make it past the stomach, or the upper intestine.”


I came across Dr. Goodenowe’s work last month from clicking a comment on this blog that linked back to her blog. Always be curious.

Continued in Part 2.

Eat broccoli sprouts for your high intensity interval training

This 2023 human study investigated broccoli sprouts and HIIT:

“In the present study we applied a program of 7 consecutive days of exercise with High intensity interval training (HIIT) and twice daily administration of a glucosinolate rich sprout drink (GRS) or a placebo drink (PLA) in a double-blinded, placebo controlled, cross-over fashion. The intent was to challenge subjects’ adaptive capacity and antioxidative defence, and determine if administration of GRS in combination with exercise could activate Nrf2, enhance physical performance, and protect against potential negative effects of excessive exercise.

Broccoli raab sprouts and alfalfa sprouts (placebo) were grown in a commercial sprout growing facility, and harvested on day 5. Sprouts were homogenized in water with a ratio of 75 g of sprouts to 180 mL of water, then immediately frozen to −80° C.

Upon consumption, drinks were quickly thawed, and 50 mL apple juice concentrate was added for improved taste and masking, together with 0.75 g brown mustard seed powder containing myrosinase to facilitate conversion of glucosinolates to isothiocyanates. Broccoli sprouts contained 1.145 ± 0.035 mmol of total glucosinolates per 75 g fresh weight.

hypoglycemia

  • Markedly reduced hypoglycemia suggests that factors beyond carbohydrate intake and energy balance, such as oxidative stress, might play a pivotal role in glucose regulation. This highlights the complexity of metabolic responses to strenuous exercise, and indicates the need for further investigations.
  • Overall adaptations to acute oxidative stress induced by exercise and GRS were towards diminished oxidative stress and improved physical performance.
  • An unexpected finding in this study was that blood lactate concentrations during submaximal exercise were lower after GRS compared to PLA. Lower lactate accumulation seen after a period of training is often attributed to either an increased oxygen delivery or improved mitochondrial capacity. We did not find any significant differences in either VO2max or mitochondrial function or capacity, indicating that other, unknown mechanisms were at play.

We showed that incorporating supplementation with GRS-rich broccoli sprouts into a 7-day intense training regimen in a cohort of healthy subjects:

  1. Mitigates several markers of oxidative stress;
  2. Improves blood glucose profile; and
  3. Enhances exercise-induced adaptations.”

https://www.sciencedirect.com/science/article/pii/S2213231723002744 “Glucosinolate-rich broccoli sprouts protect against oxidative stress and improve adaptations to intense exercise training”


This study was excellent. Other human studies it cited were less so.

Reference 17 was cited for 30 mg sulforaphane. It was actually 30 mg glucoraphanin per Eat broccoli sprouts for your workouts.

Reference 18 was also cited for 30 mg sulforaphane. That study’s Materials and methods section wasn’t forthcoming on how the sulforaphane was manufactured or obtained, though, which created reproducibility issues.

PXL_20230907_105152720

Part 2 of Harnessing endogenous defenses with broccoli sprouts

The author of this 2023 paper expanded Part 1 to include further clinical evidence and four human case studies. I’ll highlight just a few items because it’s quite detailed:

“Accumulating evidence for the crucifer-derived bioactive molecule sulforaphane (SFN) in upstream cellular defence mechanisms highlights its potential as a therapeutic candidate in targeting functional gastrointestinal conditions, as well as systemic disorders. This article catalogues evolution of and rationale for a hypothesis that multifunctional sulforaphane can be utilised as the initial step in restoring ecology of the gut ecosystem.

It can do this primarily by targeting functions of intestinal epithelial cells. In many cases where primary presenting symptoms are related to aberrant intestinal function, complete or partial resolution also occurred in seemingly unrelated conditions such as inflammatory skin diseases, multiple food intolerances, histamine-like allergic reactions, and neuro-psychological disorders.

Although SFN was the primary and initial intervention, clinicians recommended that their patients consume a mixed diet of minimally processed foods rich in vegetables and other sources of phytochemicals. It was also clear that dietary recommendations alone were not capable of making changes that occurred when SFN was added.

ijms-24-13448-g004

In seeking an effective gateway for addressing digestive, immune, cardiometabolic and other chronic disease, this hypothesis proposes an approach that harnesses the endogenous processes of human cells. These processes focus on restoring homeostasis to the gut, its underlying immune network, and the companion microbiota, with the collective potential to beneficially impact all gut–organ axes.”

https://www.mdpi.com/1422-0067/24/17/13448 “The Rationale for Sulforaphane Favourably Influencing Gut Homeostasis and Gut–Organ Dysfunction: A Clinician’s Hypothesis”


The author proposed this paper as a working hypothesis to be scientifically correct. Would a null hypothesis be along the lines of “I’ll eat a clinically relevant dose of broccoli sprouts every day for twelve weeks, and nothing will change”?

Case study #1 had a timing parallel with my experiences per:

“She was able to tolerate 20 mg SFN daily after several weeks; the dose was increased to 40 mg daily by 6 weeks.”

I doubled my dose at Week 6. All case studies documented transformative experiences, but they weren’t the same types that shortly followed for me.