Month: January 2024

Improving peroxisomal function

gettingwell4 4-5 stars Advanced knowledge, Brain development, Brainstem, Cerebellum, Cerebrum, Epigenetics, Immune system, Lower brain, Memory, Stress , , , ,

A 2024 review provided details about “mysteries” in peroxisome research:

“Peroxisomes are key metabolic organelles with essential functions in cellular lipid metabolism (e.g., β-oxidation of fatty acids and synthesis of ether phospholipids, which contribute to myelin sheath formation), and metabolism of reactive oxygen species (ROS), particularly hydrogen peroxide. Loss of peroxisomal function causes severe metabolic disorders in humans.

Additional non-metabolic roles of peroxisomes have been revealed in cellular stress responses, regulation of cellular redox balance and healthy ageing, pathogen and antiviral defence, and as cellular signalling platforms. New findings also point to a role in regulation of immune responses.

In our previous reviews, we addressed the role of peroxisomes in the brain, in neurological disorders, in development of cancer, and in antiviral defence. To avoid repetition, we refer to those articles where appropriate, and to more specialised recent reviews on peroxisome biology.

418_2023_2259_Fig5

Proper functioning of peroxisomes in metabolism requires the concerted interaction with other subcellular organelles, including the endoplasmic reticulum (ER), mitochondria, lipid droplets, lysosomes, and the cytosol. A striking example of peroxisome-ER metabolic cooperation is de novo biosynthesis of ether phospholipids.

Metabolic activities of peroxisomes, such as ɑ- and β-oxidation of fatty acids, plasmalogen synthesis, and ROS/reactive nitrogen species metabolism, have been linked to numerous immune-related pathways. Roles for peroxisomes in immune and defence mechanisms have opened a new field of peroxisome research, and highlight once more how important peroxisomes are for human health and disease.

It is still not fully understood how peroxisomal functions and abundance are regulated, what kinases/phosphatases are involved, or how peroxisomes are linked to cellular signalling pathways and how they act as signalling platforms.”

https://link.springer.com/article/10.1007/s00418-023-02259-5 “The peroxisome: an update on mysteries 3.0”

Last Friday was Day 90 of a 90-day trial of plasmalogens coincident with improving peroxisomal function via resistance exercise and time-restricted eating. A sticking point has been leg resistance exercises. Ankle issues are interfering with progress, although beach walks aren’t similarly affected. I’m almost back to an upper body exercise routine of five years ago, and I’ve added a half-dozen abs exercises.

I’ll continue taking the two Prodrome plasmalogen precursor supplements (ProdromeGlia and ProdromeNeuro) and with efforts to improve peroxisomal function. Since achieving effective resistance exercise levels is taking longer than expected, and my crystal ball is out-of-commission, I don’t have a realistic end time estimate for stopping the supplements.

Get a little stress into your life

gettingwell4 4-5 stars Advanced knowledge, Epigenetics, Immune system, Stress , , ,

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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Eat broccoli sprouts for your liver, Part 2

gettingwell4 2-3 stars Required further work, Epigenetics, Immune system, Stress , ,

A 2023 review cited Part 1 and caught up other relevant research on sulforaphane effects through early 2023:

“A growing number of studies have reported that sulforaphane (SFN) could significantly ameliorate hepatic steatosis and prevent development of fatty liver, improve insulin sensitivity, attenuate oxidative damage and liver injury, induce apoptosis, and inhibit proliferation of hepatoma cells through multiple signaling pathways.

SFN inhibits lipogenesis and oxidative stress while enhancing lipid droplet degradation through modulating expression of genes involved in lipid synthesis, metabolism, and oxidation. SFN modulates autophagy, lipolysis, mitochondrial function, and ER stress to alleviate fatty liver through AMPK-, AHR-, PGC1α-, and FGF21-mediated pathways.

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There is still a gap between basic research and clinical application of SFN. More efficient delivery systems and precise dose schedules of SFN are expected to be developed in future studies, which would improve its solubility, stability, and bioavailability, and reduce inter-individual variations in humans.”

https://www.frontiersin.org/articles/10.3389/fphar.2023.1256029/full “Therapeutic potential of sulforaphane in liver diseases: a review”

These reviewers did alright gathering papers. That’s only part of what needed to be done, with the other part being reading, understanding, and interpreting these papers.

First example: Sulforaphane in the Goldilocks zone was cited [reference 12], but applicability to this review with its main point “The stimulatory zone for in vitro studies proved to be consistently in the 1-10 μM range” as in Figure 10 “Effects of R-sulforaphane on phase II enzyme activation in precision-cut liver slices of young adult male Albino Wistar rats” wasn’t understood:

figure 10

These reviewers complained:

“Few dose-response studies on SFN have been reported, and the range of its effective doses is unclear. Doses used in most animal studies have exceeded the highest dose of SFN used in humans.”

So it might have taken a little bit more effort, but these reviewers could have highlighted studies where sulforaphane liver treatments were in the 1-10 μM potentially therapeutic range.

Another example: these reviewers said “The half-life of SFN is very short due to its rapid metabolism in the human body.” They missed a point that the second paper in How much sulforaphane is suitable for healthy people? [reference 46] made in section 6.4. “NQO1 Pharmacokinetics following SFN Ingestion:”

“Maximal induction of NQO1 occurred at around 24 hours, declining thereafter (Figure 8). This peak represents an approximate 2.8-fold induction over baseline.

These findings are useful when considering the effect of SFN as an intervention material in acute compared with chronic conditions. A significant increase in NQO1 occurred between 6 and 12 hours, a timeframe that may not be sufficiently responsive for management of an acute state, leaving one to conclude that NQO1 induction is best suited to chronic conditions where a rapid response may not be necessary.”

OMCL2019-2716870.008

Sulforaphane’s effects of inducing NQO1 for its cytoprotective, antioxidant, and other functions lasts for days, regardless of when sulforaphane leaves the bloodstream.

Taurine’s effects on healthspan and lifespan, Part 2

gettingwell4 4-5 stars Advanced knowledge, Cerebrum, Cortisol, Epigenetics, Hypothalamus, Limbic system, Memory, Neurochemicals, Stress , ,

Four 2023 papers that cited Part 1, starting with a review of hypothetical parameters for taurine clinical trials that aren’t going to happen because:

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

“We propose the rationale that an adequately powered randomized-controlled-trial (RCT) is needed to confirm whether taurine can meaningfully improve metabolic and microbiome health, and biological age.

taurine hypothetical trial

Using long-term survival as a primary outcome is desirable but difficult; any demonstrable difference in this outcome will require a substantial sample size with prolonged follow-up (e.g., 5 years or longer) if the effect size is relatively small (or modest at best). Biological age based on DNA methylation biomarkers according to the Levine PhenoAge or newer biological age models is increasingly being recognized as an important dynamic health parameter, and hence it can also be used as a surrogate outcome in assessing benefits of taurine supplementation.

The recent taurine trial on nonhuman primates used an equivalent dose that was between 3 and 6 g per day for an 80-kg person, and this could represent a reasonable dose range for any human RCTs. We believe that a 6-month or longer interventional period matching what was successfully done on nonhuman primates will be an acceptable time frame in assessing potential efficacy of taurine on human metabolic health in a RCT.”

https://www.sciopen.com/article/10.26599/1671-5411.2023.11.004 “Flattening the biological age curve by improving metabolic health: to taurine or not to taurine, that’s the question”

A six-month duration and a 6 grams per day dose were in the above table’s desirable features column, but epigenetic clock measurements weren’t included as an outcome. I’d guess that its omission reflected disagreements among coauthors, because the desirability of using epigenetic clocks as surrogate measures of human healthspan and lifespan was mentioned several times.

Another review:

“As described in the first half of this review, recent advances in omics analysis technology have led to research to detect the causative gene of dilated cardiomyopathy. It has been found that rare mutations in the taurine transporter gene contribute to the development of dilated cardiomyopathy in humans. It is unlikely that a taurine-deficient diet is a factor in dilated cardiomyopathy, but taurine intake may have positive cardiovascular effects.

The second half summarizes the relationship between taurine and healthspan and lifespan. It is difficult to summarize the effect of age in whole body taurine content, which may vary in species, strain, sex, and age of animal models. Future human studies will clarify the relationship between dietary taurine intake and healthy life expectancy.”

https://www.sciencedirect.com/science/article/pii/S1347861323000749 “Taurine deficiency associated with dilated cardiomyopathy and aging”

A human study investigated brain chemicals that fluctuate with our circadian rhythm:

“We conducted a MRS study at 7 T, where occipital NAD content, lactate, and other metabolites were assessed in two different morning and afternoon diurnal states in healthy participants. Salivary cortisol levels were determined to confirm that the experiment was done in two circadian different physiological conditions.

Although no significant differences in NAD+, NADH, and NAD+/NADH were detected between the morning and afternoon sessions, there was a significant variance difference in NAD+/NADH, with a higher variance of NAD+/NADH redox ratio in the morning.

None of the over 30 measured brain metabolites were significantly affected by the circadian rhythm (CR) except for taurine, which decreased in the afternoon. Further CR studies should consider the prospective measurement of taurine levels in different regions of the human brain, and explore how taurine supplements could impact brain CR metabolism in health and diseases.”

https://www.frontiersin.org/articles/10.3389/fphys.2023.1285776/full “Effect of circadian rhythm on NAD and other metabolites in human brain”

I omitted findings regarding this study’s pathetic Balloon Analogue Risk Task (BART) test. Older studies that drew spurious findings from this video game include:

A rodent study modeled human childhood cataracts:

“Our analysis identified targets that are required for early normal differentiation steps and altered in cataractous lenses, particularly metabolic pathways involving glutathione and amino acids. Glutathione and taurine were spatially altered, and both taurine and the ratio of reduced glutathione to oxidized glutathione, two indicators of redox status, were differentially compromised in lens biology.

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Dietary amino acid supplementation has been shown to prevent cataract development, and dietary intake of taurine was protective in a glutathione depletion-derived opacity model. This opens up the possibility that dietary supplementation of taurine could be used as a strategy to prevent human congenital cataracts.

Our findings shed light on molecular mechanisms associated with congenital cataracts, and point out that unbalanced redox status due to reduced levels of taurine and glutathione, metabolites already linked to age-related cataracts, could be a major underlying mechanism behind lens opacities that appear early in life.”

https://www.sciencedirect.com/science/article/pii/S2213231723002707 “Unbalanced redox status network as an early pathological event in congenital cataracts”

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The TMAO meme

gettingwell4 0-1 star Wasted resources

A common dilemma for researchers is how to follow the herd enough to get a paper published, while simultaneously presenting replicable evidence of tested hypotheses. But unlike study researchers, reviewers are free to:

  • Express their beliefs as facts;
  • Over/under emphasize study limitations; and
  • Disregard and misrepresent evidence as they see fit.

Reviewers also aren’t obligated to make post-publication corrections for their errors and distortions.

Here’s one of a dozen 2023 papers I read this week on TMAO. I picked this review because they attempted to come clean at the end of several sections.

I rated it as Wasted resources rather than Detracted from science as there might be a slight sniff of facts underneath the stench. Facts do not include “is associated with” or “is correlated with.”

The meme (repeated many times):

“Overall diet, lifestyle choices, genetic predisposition, and other underlying health conditions may contribute to higher trimethylamine N-oxide (TMAO) levels and increased cardiovascular risk. This review explores the potential therapeutic ability of resveratrol (RSV) to protect against cardiovascular diseases (CVD) and affect TMAO levels.”

Sections starting with premises that contained contradictions included:

2.2. TMAO and cardiovascular disease

Higher TMAO levels raise the risk of adverse cardiovascular events.

Overall, eating fish with high TMAO levels has relatively few adverse effects on CVD.

2.2.1 Relationship between TMAO and atherogenesis

Collectively, these findings provide a possible link between gut bacteria, platelet activation, and the risk of thrombosis.

More research is required to show the function of TMAO in the formation of CVD.

3. Application potential of phytochemicals such as polyphenols, RSV and its modified derivatives in regulating CVD

TMAO is a unique and independent risk factor for developing AS, partly through suppression of hepatic bile acid production.

Eating plants in general affects TMAO levels.

3.1. TMAO-lowering phytochemicals

Since the discovery of TMAO as a pro-atherogenic metabolite is relatively recent, only relatively small numbers of polyphenol-rich extracts and single phenolic compounds have been investigated as TMA/TMAO lowering agents.

Cardioprotective function of phytochemicals may arise from a combination of different mechanisms.

And so on.

https://febs.onlinelibrary.wiley.com/doi/10.1002/2211-5463.13762 “Cardiovascular risk of dietary trimethylamine oxide precursors and the therapeutic potential of resveratrol and its derivatives”

How many people would be healthy after they stopped eating fish, meat, and foods that had choline, carnitine, betaine, or ergothioneine? There are no clinical trials that omit all of these “TMAO precursors” from human diets because people would die.

Propagating the TMAO meme is dumb. It isn’t politically driven AFAIK, though, so doesn’t drop to the sub-basement evidence levels of politically correct memes.

2016 meme