Reversal of aging and immunosenescent trends

The title of this post is essentially the same as the 2019 human clinical trial:

“Epigenetic aging can be reversed in humans. Using a protocol intended to regenerate the thymus, we observed protective immunological changes, improved risk indices for many age‐related diseases, and a mean epigenetic age approximately 1.5 years less than baseline after 1 year of treatment.

This is to our knowledge the first report of an increase, based on an epigenetic age estimator, in predicted human lifespan by means of a currently accessible aging intervention.”

“Example of treatment‐induced change in thymic MRI appearance. Darkening corresponds to replacement of fat with nonadipose tissue. White lines denote the thymic boundary. Volunteer 2 at 0 (a) and 9 (b) months”

https://onlinelibrary.wiley.com/doi/full/10.1111/acel.13028 “Reversal of epigenetic aging and immunosenescent trends in humans”


Here’s a 2017 interview with the clinical trial lead author:

“You might also say that what also happened was to just postpone death from infectious diseases to after 60-65 years of age, which means that the same basic problem still remains.”


The popular press botched the facts as they usually do. I won’t link the UK Independent article because they couldn’t be bothered to even define epigenetic clock correctly.

A science journal article did a better job of explaining the study to readers. However, they often used hyperbole instead of trying to promote understanding.

Josh Mitteldorf’s blog post 1st Age Reversal Results—Is it HGH or Something Else? provided the most informative explanations:

“In 2015, Fahy finally had funding and regulatory approval to replicate his one-man trial in a still-tiny sample of ten men, aged 51-65. That it took so long is an indictment of everything about the way aging research is funded in this country; and not just aging – all medical research is prioritized according to projected profits rather than projected health benefits.”

Take care reading the post’s comments. Both non-scientist (such as Mark, Adrian, and others) and scientist commentators (such as Gustavo, Jeff, and others) attempted to hijack the discussion into their pet theories of reality in which they imagined themselves to be the definitive authorities. My discussion comment – with respect to a Mayo Clinic warning about DHEA – was: “19 instances of the word ‘might’ doesn’t lend itself to credibility.”

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PNAS politics in the name of science

This 2019 Germany/Canada human fetal cell study was a Proceedings of the National Academy of Sciences of the United States of America direct submission:

“In a human hippocampal progenitor cell line, we assessed the short- and long-term effects of GC [glucocorticoid] exposure during neurogenesis on messenger RNA expression and DNA methylation profiles. Our data suggest that early exposure to GCs can change the set point of future transcriptional responses to stress by inducing lasting DNAm changes.”


The study’s basic finding was that cells had initial responses to stressors that primed them for subsequent stressors. Since this finding wasn’t new, the researchers tried to make it exciting by applying it to novel contexts that were yet circumscribed by official paradigms.

Hypothesis-seeking associations of human fetal hippocampal cell behaviors with human behaviors were flimsy stretches, as were correlations to placental measurements. These appeared to have been efforts to find headline-making effects.

There wasn’t even a hint of the principle described in Epigenetic variations in metabolism:

“Because of the extreme interconnectivity of cell regulatory networks, even at the cellular level, predicting the impact of a sequence variant is difficult as the resultant variation acts:

  • In the context of all other variants and
  • Their potential additive, synergistic and antagonistic interactions.

This phenomenon is known as epistasis.”

It would have condemned pet models of reality to admit that a cell exists in multiple contexts of other cells with potential additive, synergistic, and antagonistic interactions.

A research proposal to trace a specific cell type’s behaviors – while isolated from their extremely interconnected networks – to trillion-celled human behaviors would be rejected in less-politicized organizations.

Sanctioned speculations manifested in this paper with phrases such as “although not significant..” and “although not directly tested..” The study’s title was probably a disappointment in that it conformed to the study’s evidence.

Involvements of psychiatry departments at the pictured Kings College, Harvard, etc., as part of PNAS entrenched politics, retard advancements of science past approved paradigms.

This is my final curation of PNAS papers.

https://www.pnas.org/content/pnas/early/2019/08/08/1820842116.full.pdf “Glucocorticoid exposure during hippocampal neurogenesis primes future stress response by inducing changes in DNA methylation”

Developmental disorders and the epigenetic clock

This 2019 UK/Canada/Germany human study investigated thirteen developmental disorders to identify genes that changed aspects of the epigenetic clock:

“Sotos syndrome accelerates epigenetic aging [+7.64 years]. Sotos syndrome is caused by loss-of-function mutations in the NSD1 gene, which encodes a histone H3 lysine 36 (H3K36) methyltransferase.

This leads to a phenotype which can include:

  • Prenatal and postnatal overgrowth,
  • Facial gestalt,
  • Advanced bone age,
  • Developmental delay,
  • Higher cancer predisposition, and, in some cases,
  • Heart defects.

Many of these characteristics could be interpreted as aging-like, identifying Sotos syndrome as a potential human model of accelerated physiological aging.

This research will shed some light on the different processes that erode the human epigenetic landscape during aging and provide a new hypothesis about the mechanisms behind the epigenetic aging clock.”

“Proposed model that highlights the role of H3K36 methylation maintenance on epigenetic aging:

  • The H3K36me2/3 mark allows recruiting de novo DNA methyltransferases DNMT3A (in green) and DNMT3B (not shown).
  • DNA methylation valleys (DMVs) are conserved genomic regions that are normally found hypomethylated.
  • During aging, the H3K36 methylation machinery could become less efficient at maintaining the H3K36me2/3 landscape.
  • This would lead to a relocation of de novo DNA methyltransferases from their original genomic reservoirs (which would become hypomethylated) to other non-specific regions such as DMVs (which would become hypermethylated and potentially lose their normal boundaries),
  • With functional consequences for the tissues.”

The researchers improved methodologies of several techniques:

  1. “Previous attempts to account for technical variation have used the first 5 principal components estimated directly from the DNA methylation data. However, this approach potentially removes meaningful biological variation. For the first time, we have shown that it is possible to use the control probes from the 450K array to readily correct for batch effects in the context of the epigenetic clock, which reduces the error associated with the predictions and decreases the likelihood of reporting a false positive.
  2. We have confirmed the suspicion that Horvath’s model underestimates epigenetic age for older ages and assessed the impact of this bias in the screen for epigenetic age acceleration.
  3. Because of the way that the Horvath epigenetic clock was trained, it is likely that its constituent 353 CpG sites are a low-dimensional representation of the different genome-wide processes that are eroding the epigenome with age. Our analysis has shown that these 353 CpG sites are characterized by a higher Shannon entropy when compared with the rest of the genome, which is dramatically decreased in the case of Sotos patients.”

https://genomebiology.biomedcentral.com/articles/10.1186/s13059-019-1753-9 “Screening for genes that accelerate the epigenetic aging clock in humans reveals a role for the H3K36 methyltransferase NSD1”

Too cheap for clinical trials

Let’s compare and contrast a 2019 meta-analysis and a 2017 review of using acetyl-L-carnitine to treat diabetic neuropathy.

A 2019 Brazilian meta-analysis Acetyl‐L‐carnitine for the treatment of diabetic peripheral neuropathy of four previous trials stated:

  • “The risk of bias was high in both trials of different ALC doses and low in the other two trials.
  • No included trial measured the proportion of participants with at least moderate (30%) or substantial (50%) pain relief.
  • At doses greater than 1500 mg/day, ALC reduced pain more than placebo. This subgroup analysis should be viewed with caution as the evidence was even less certain than the overall analysis, which was already of very low certainty.
  • The placebo-controlled studies did not measure functional impairment and disability scores.
  • No study used validated symptom scales.
  • Two studies were funded by the manufacturer of ALC and the other two studies had at least one co-author who was a consultant for an ALC manufacturer.

Authors’ conclusions:

  • We are very uncertain whether ALC causes a reduction in pain after 6 to 12 months treatment in people with DPN, when compared with placebo, as the evidence is sparse and of low certainty.
  • Data on functional and sensory impairment and symptoms are lacking, or of very low certainty.
  • The evidence on adverse events is too uncertain to make any judgements on safety.”

A 2017 Italian review Effects of acetyl-L-carnitine in diabetic neuropathy and other geriatric disorders stated:

“A long history of diabetes mellitus and increasing age are associated with the onset of diabetic neuropathy, a painful and highly disabling complication with a prevalence peaking at 50% among elderly diabetic patients. The management of diabetic neuropathy is extremely difficult: in addition to the standard analgesics used for pain control, common treatments include opioids, anticonvulsants, antidepressants, and local anesthetics, alone or in combination. Such therapies still show a variable, often limited efficacy, however.

Many patients do not spontaneously report their symptoms to physicians, but, if asked, they often describe having experienced a persistent and non-abating pain for many years. The prevalence of painful symptoms is just as high in patients with mild neuropathy as in those with more advanced DPN.

Through the donation of acetyl groups, ALC exerts a positive action on mitochondrial energy metabolism. ALC has cytoprotective, antioxidant, and antiapoptotic effects in the nervous system.

ALC has also been proposed for the treatment of other neurological and psychiatric diseases, such as mood disorders and depression, dementia, Alzheimer’s disease, and Parkinson’s disease, given that synaptic energy states and mitochondrial dysfunctions are core factors in their pathogenesis. Compared to other treatments, ALC is safe and extremely well tolerated.”

“In nerve injury, the mGlu2 receptor overexpressed by ALC binds the glutamate, reducing its concentration in the synapses with an analgesic effect. ALC may improve nerve regeneration and damage repair after primary nerve trauma.”


Where will the money come from to realize what the 2017 review promised, as well as provide what the 2019 meta-analysis required?

Do we prefer the current “limited efficacy” treatments of “opioids, anticonvulsants, antidepressants, and local anesthetics?”

Who will initiate clinical trials of a multiple of the normal dietary supplement dose (500 mg at $.25 a day, retail)? How profitable is a product whose hypothetical effective dosage for diabetic neuropathy (3000 mg) sells for only $1.50 a day?

Effects of advanced glycation end products on quality of life and lifespan

This 2018 Chinese review concerned advanced glycation end products (AGE) mobility interventions:

“Only a limited number of studies have focused on measuring the effects of low AGEs levels or AGEs inhibitors on mobility, although many observational human studies and in vitro studies have reported the correlation of AGEs with and the contribution of AGEs to mobility, particular in diseases such as:

  • osteoporosis,
  • cartilage degradation,
  • osteoarthritis and
  • sarcopenia.

There is insufficient information from previous animal and human studies for use as a reference to determine the intervention period. Although serum AGEs levels can be easily affected by a lower AGEs diet or AGEs inhibitors, it may take longer to see the changes in certain organs or tissues, as a result of a reduction in AGEs accumulation.”

 

“Effect of AGEs on apoptosis signalling. AP-1, activator protein 1; ERK, extracellular signal-regulated protein kinases; IGF-I, insulin-like growth factor I; IL-6, interleukin-6; JAK, Janus kinase; JNK, c-Jun N-terminal kinases; MEK, mitogen-activated protein kinase; NF-κB, nuclear factor kappa B; p38 MAPK, p38 mitogen-activated protein kinase; RAGE, receptor for AGEs; STAT3, signal transducers and activators of transcription 3; TGF-β, transforming growth factor-β”


Citations aren’t validations of the reference’s quality and strength of evidence. This review would have benefited from not citing reviews that contained misrepresentations, such as one mentioned in Wikipedia is a poor source of information on advanced glycation end products (AGEs).

I came across this review as a result of it citing the excellent 2008 rodent study Oral Glycotoxins Determine the Effects of Calorie Restriction on Oxidant Stress, Age-Related Diseases, and Lifespan which found:

“Higher levels of oxidant AGEs in offspring of Reg-F0 dams may be attributable to placental transmission from mothers with high AGE levels. These high intrauterine AGE levels may predispose the offspring to the development of chronic inflammation and diseases in adulthood, such as insulin resistance and diabetes.

Increasing the intake of AGEs in the diet erases the benefits of CR [calorie restriction]. OS [oxidant stress] can be reduced, and healthspan increased, in mice fed a diet that is restricted in the content of AGEs.

The beneficial effects of a CR diet may be partly related to reduced oxidant intake rather than decreased energy intake.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6180645/ “Role of advanced glycation end products in mobility and considerations in possible dietary and nutritional intervention strategies”

Online dating cuts out the middlemen

This information is from a 2019 prepublication Stanford study:

“We present new data from a nationally representative 2017 survey showing that meeting online has continued to grow for heterosexual couples, and meeting through friends has continued its sharp decline. As a result of the continued rise of meeting online and the decline of meeting through friends, online has become the most popular way heterosexual couples in the U.S.

Meeting through friends and family provided guarantees that any potential partner had been personally vetted and vouched for by trusted alters. We would expect any rise in Internet dating to reinforce rather than to displace the traditional roles of friends and family as introducers and intermediaries. [Hypothesis 2]

Results reflect support of Hypothesis 1, as the percentage of heterosexual couples meeting online has surged in the post‐2009 smart phone era. Because the results show that meeting online has displaced meeting through friends and meeting through family, we find evidence to reject Hypothesis 2, which led us to expect that online dating would reinforce existing face‐to‐face social networks.”

“Figure 1’s apparent post‐2010 rise in meeting through bars and restaurants for heterosexual couples is due entirely to couples who met online and subsequently had a first in‐person meeting at a bar or restaurant or other establishment where people gather and socialize. If we exclude the couples who first met online from the bar/restaurant category, the bar/restaurant category was significantly declining after 1995 as a venue for heterosexual couples to meet.”


Are there examples where it wouldn’t potentially improve a person’s life to choose their information sources? Friends, family, and other social groups, and religious, educational, and other institutions have had their middlemen/guarantor time, and have been found lacking.

Make your own choices for your one precious life. Similar themes are explored in:

https://web.stanford.edu/~mrosenfe/Rosenfeld_et_al_Disintermediating_Friends.pdf “Disintermediating your friends”

Perinatal stress and sex differences in circadian activity

This 2019 French/Italian rodent study used the PRS model to investigate its effects on circadian activity:

“The aim of this study was to explore the influence of PRS on the circadian oscillations of gene expression in the SCN [suprachiasmatic nucleus of the hypothalamus] and on circadian locomotor behavior, in a sex-dependent manner.

Research on transcriptional rhythms has shown that more than half of all genes in the human and rodent genome follow a circadian pattern. We focused on genes belonging to four functional classes, namely the circadian clock, HPA axis stress response regulation, signaling and glucose metabolism in male and female adult PRS rats.

Our findings provide evidence for a specific profile of dysmasculinization induced by PRS at the behavioral and molecular level, thus advocating the necessity to include sex as a biological variable to study the set-up of circadian system in animal models.”

“There was a clear-cut effect of sex on the effect of PRS on the levels of activity:

  • During the period of lower activity (light phase), both CONT and PRS females were more active than males. During the light phase, PRS increased activity in males, which reached levels of CONT females.
  • More interestingly, during the period of activity (dark phase), male PRS rats were more active than male CONT rats. In contrast, female PRS rats were less active than CONT females.
  • During the dark phase, CONT female rats were less active than CONT male rats.

The study presented evidence for sex differences in circadian activity of first generation offspring that was caused by stress experienced by the pregnant mother:

“Exposure to gestational stress and altered maternal behavior programs a life-long disruption in the reactive adaptation such as:

  •  A hyperactive response to stress and
  • A defective feedback of the hypothalamus-pituitary-adrenal (HPA) axis together with
  • Long-lasting modifications in stress/anti-stress gene expression balance in the hippocampus.”

It would advance science if these researchers carried out experiments to two more generations to investigate possible transgenerational epigenetic inheritance of effects caused by PRS. What intergenerational and transgenerational effects would they possibly find by taking a few more months and extending research efforts to F2 and F3 generations? Wouldn’t these findings likely help humans?

One aspect of the study was troubling. One of the marginally-involved coauthors was funded by the person described in How one person’s paradigms regarding stress and epigenetics impedes relevant research. Although no part of the current study was sponsored by that person, there were three gratuitous citations of their work.

All three citations were reviews. Unlike study researchers, reviewers aren’t bound to demonstrate evidence from tested hypotheses. Reviewers are free to:

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

Fair or not, comparisons of reviews with Cochrane meta-analyses of the same subjects consistently show the extent of reviewers’ biases. Reviewers also aren’t obligated to make post-publication corrections for their errors and distortions.

As such, reviews can’t be cited for reliable evidence. Higher-quality studies that were more relevant and recent than a 1993 review could have elucidated items 26 years later in 2019.

Sucking up to the boss and endorsing their paradigm was predictable. Since that coauthor couldn’t constrain themself to funder citations only in funder studies, it was the other coauthors’ responsibilities to edit out unnecessary citations.

https://www.frontiersin.org/articles/10.3389/fnmol.2019.00089/full “Perinatal Stress Programs Sex Differences in the Behavioral and Molecular Chronobiological Profile of Rats Maintained Under a 12-h Light-Dark Cycle”