Caloric restriction’s epigenetic effects

This 2019 US review subject was caloric restriction (CR) without malnutrition:

“Cellular adaptation that occurs in response to dietary patterns can be explained by alterations in epigenetic mechanisms such as DNA methylation, histone modifications, and microRNA. Epigenetic reprogramming of the underlying chronic low-grade inflammation by CR can lead to immuno-metabolic adaptations that enhance quality of life, extend lifespan, and delay chronic disease onset.

Short- and long-term CRs produce significant changes in different tissues and across species, in some animal models even with sex-specific effects. Early CR onset may cause a different and even an opposite effect on physiological outcomes in animal models such as body weight.”

 


Charts usually don’t have two different values plotted on the same axis. There wasn’t evidence that equated survival with methylation drift per the above graphic. Methylation drift should point in the opposite direction of survival, if anything.

No mention was made of the epigenetic clock method of measuring age acceleration, although recent diet studies have used it. The sole citation of an age acceleration study was from 2001, which was unacceptable for a review published in 2019.

The review provided many cellular-level details about the subject. However, organism-level areas weren’t sufficiently evidenced:

1. Arguments for an effect usually include explanations for no effect as well as opposite effects. The reviewers didn’t provide direct evidence for why, if caloric restriction extended lifespan, caloric overabundance produced shorter lifespans.

2. Caloric restriction evidence was presented as if only it was responsible for organism-level effects. Other mechanisms may have been involved.

An example of such a mechanism was demonstrated in a 2007 rodent study Reduced Oxidant Stress and Extended Lifespan in Mice Exposed to a Low Glycotoxin Diet which compared two 40%-calorie-restricted diets.

The calories and composition of both diets were identical. However, advanced glycation end product (AGE) levels were doubled in standard chow because heating temperatures were “sufficiently high to inadvertently cause standard mouse chow to be rich in oxidant AGEs.”

The study found that a diet with lower chow heating temperatures increased lifespan and health span irrespective of caloric restriction!

  • The low-AGE calorie-restricted diet group lived an average of 15% longer (>20 human equivalent years) than the standard calorie-restricted diet group. 40% of the low-AGE calorie-restricted diet group were still alive when the last standard calorie-restricted diet group member died.
  • The standard calorie-restricted diet group also had significantly more: 1) oxidative stress damage; 2) glucose and insulin metabolism problems; and 3) kidney, spleen, and liver injuries.

https://academic.oup.com/advances/article-abstract/10/3/520/5420411 “Epigenetic Regulation of Metabolism and Inflammation by Calorie Restriction” (not freely available)

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Do delusions have therapeutic value?

This 2019 UK review discussed delusions, aka false beliefs about reality:

“Delusions are characterized by their behavioral manifestations and defined as irrational beliefs that compromise good functioning. In this overview paper, we ask whether delusions can be adaptive notwithstanding their negative features.

We consider different types of delusions and different ways in which they can be considered as adaptive: psychologically (e.g., by increasing wellbeing, purpose in life, intrapsychic coherence, or good functioning) and biologically (e.g., by enhancing genetic fitness).”


1) Although the review section 4 heading was Biological Adaptiveness of Delusions, the reviewers never got around to discussing the evolved roles of brain areas. One mention of evolutionary biology was:

“Delusions are biologically adaptive if, as a response to a crisis of some sort (anomalous perception or overwhelming distress), they enhance a person’s chances of reproductive success and survival by conferring systematic biological benefits.”

2) Although section 5’s heading was Psychological Adaptiveness of Delusions, the reviewers didn’t connect feelings and survival sensations as origins of beliefs (delusions) and behaviors. They had a few examples of feelings:

“Delusions of reference and delusions of grandeur can make the person feel important and worthy of admiration.”

and occasionally sniffed a clue:

“Some delusions (especially so‐called motivated delusions) play a defensive function, representing the world as the person would like it to be.”

where “motivated delusions” were later deemed in the Conclusion section to be a:

“Response to negative emotions that could otherwise become overwhelming.”

3) Feelings weren’t extensively discussed until section 6 Delusions in OCD and MDD, which gave readers the impression that feelings were best associated with those diseases.

4) In the Introduction, sections 4, 5, and 7 How Do We Establish and Measure Adaptiveness, the reviewers discussed feeling meaning in life, but without understanding:

  1. Feelings = meaning in life, as I quoted Dr. Arthur Janov in The pain societies instill into children:

    “Without feeling, life becomes empty and sterile. It, above all, loses its meaning.

  2. Beliefs (delusions) defend against feelings.
  3. Consequentially, the stronger and more numerous beliefs (delusions) a person has, the less they feel meaning in life.

5) Where, when, why, and how do beliefs (delusions) arise? Where, when, why, and how does a person sense and feel, and what are the connections with beliefs (delusions)?

The word “sense” was used 29 times in contexts such as “make sense” and “sense of [anxiety, coherence, control, meaning, purpose, rational agency, reality, self, uncertainty]” but no framework connected biological sensing to delusions. Papers from other fields have detailed cause-and-effect explanations and precursor-successor diagrams for every step of a process.


Regarding the therapeutic value of someone else’s opinion of a patient’s delusions – I’ll reuse this quotation from the Scientific evidence page of Dr. Janov’s 2011 book “Life Before Birth: The Hidden Script that Rules Our Lives” p.166:

“Primal Therapy differs from other forms of treatment in that the patient is himself a therapist of sorts. Equipped with the insights of his history, he learns how to access himself and how to feel.

The therapist does not heal him; the therapist is only the catalyst allowing the healing forces to take place. The patient has the power to heal himself.

Another way Dr. Janov wrote this was on p.58 of his 2016 book Beyond Belief as quoted in Beyond Belief: The impact of merciless beatings on beliefs:

No one has the answer to life’s questions but you. How you should lead your life depends on you, not outside counsel.

We do not direct patients, nor dispense wisdom upon them. We have only to put them in touch with themselves; the rest is up to them.

Everything the patient has to learn already resides inside. The patient can make herself conscious. No one else can.”

https://onlinelibrary.wiley.com/doi/full/10.1002/wcs.1502 “Are clinical delusions adaptive?”

Non-emotional memories

This 2019 US review covered memory mechanisms:

“With memory encoding reliant on persistent changes in the properties of synapses, a key question is how can memories be maintained from days to months or a lifetime given molecular turnover? It is likely that positive feedback loops are necessary to persistently maintain the strength of synapses that participate in encoding.

These levels are not isolated, but linked by shared components of feedback loops.”


Despite the review’s exhaustive discussion, the reviewers never came to the point. The word cloud I made of the review’s most frequent thirty words had little to do with why memory occurs:

  • Why do some stimuli evoke a memory in response?
  • Why are almost all of the stimuli an organism receives not remembered?

Much of the discussion was baseless because it excluded emotion. Many of the citations’ memory findings relied on emotion, though.

For example, in the subsection Roles of persistent epigenetic modifications for maintaining LTF [long-term facilitation], LTP [long-term potentiation], and LTM [long-term memory]:

  • Histone acetylation is increased after fear conditioning in the hippocampus and amygdala.
  • Correspondingly, inhibition of histone deacetylase enhances fear conditioning and LTP.
  • Following fear conditioning, histone phosphorylation is also increased.
  • DNA methylation is also up-regulated in the hippocampus and amygdala after fear conditioning, and inhibition of DNA methylation blocks fear LTM.”

http://learnmem.cshlp.org/content/26/5/133.full “How can memories last for days, years, or a lifetime? Proposed mechanisms for maintaining synaptic potentiation and memory”

Our brains are shaped by our early environments

This 2019 McGill paper reviewed human and animal studies on brain-shaping influences from the fetal period through childhood:

“In neonates, regions of the methylome that are highly variable across individuals are explained by the genotype alone in 25 percent of cases. The best explanation for 75 percent of variably methylated regions is the interaction of genotype with different in utero environments.

A meta-analysis including 45,821 individuals with attention-deficit/hyperactivity disorder and 9,207,363 controls suggests that conditions such as preeclampsia, Apgar score lower than 7 at 5 minutes, breech/transverse presentations, and prolapsed/nuchal cord – all of which involve some sort of poor oxygenation during delivery – are significantly associated with attention-deficit/hyperactivity disorder. The dopaminergic system seems to be one of the brain systems most affected by perinatal hypoxia-ischemia.

Exposure to childhood trauma activates the stress response systems and dysregulates serotonin transmission that can adversely impact brain development. Smaller cerebral, cerebellar, prefrontal cortex, and corpus callosum volumes were reported in maltreated young people as well as reduced hippocampal activity.

Environmental enrichment has a series of beneficial effects associated with neuroplasticity mechanisms, increasing hippocampal volume, and enhancing dorsal dentate gyrus-specific differences in gene expression. Environmental enrichment after prenatal stress decreases depressive-like behaviors and fear, and improves cognitive deficits.”


The reviewers presented strong evidence until the Possible Factors for Reversibility section, which ended with the assertion:

“All these positive environmental experiences mentioned in this section could counterbalance the detrimental effects of early life adversities, making individuals resilient to brain alterations and development of later psychopathology.”

The review’s penultimate sentence recognized that research is seldom done on direct treatments of causes:

“The cross-sectional nature of most epigenetic studies and the tissue specificity of the epigenetic changes are still challenges.”

Cross-sectional studies won’t provide definitive data on cause-and-effect relationships.

The question yet to be examined is: How can humans best address these early-life causes to ameliorate their lifelong effects?

https://onlinelibrary.wiley.com/doi/full/10.1111/dmcn.14182 “Early environmental influences on the development of children’s brain structure and function” (not freely available)

An hour of the epigenetic clock

This 2018 presentation by the founder of the epigenetic clock method described the state of the art up through July 2018. The webinar was given on the release day of The epigenetic clock now includes skin study.


Segments before the half-hour mark provide an introduction to the method and several details about the concurrently-released study. The Q&A section starts a little before the hour mark.

Fear of feeling?

Here’s a 2018 article from two researchers involved in the Dunedin (New Zealand) Longitudinal Study. They coauthored many studies, including People had the same personalities at age 26 that they had at age 3.

The paper’s grand hypothesis was:

“A single dimension is able to measure a person’s liability to mental disorder, comorbidity among disorders, persistence of disorders over time, and severity of symptoms.”

The coauthors partially based this on:

“Repeated diagnostic interviews carried out over 25 years, when the research participants were 11, 13, 15, 18, 21, 26, 32, and 38 years old, and include information about seven diagnostic groups: anxiety, depression, attention deficit hyperactivity disorder, conduct disorder, substance dependence, bipolar disorder, and schizophrenia.”


https://ajp.psychiatryonline.org/doi/full/10.1176/appi.ajp.2018.17121383 “All for One and One for All: Mental Disorders in One Dimension” (not freely available)


More about the coauthors:

Two psychologists followed 1000 New Zealanders for decades. Here’s what they found about how childhood shapes later life

“Dunedin and other studies show that most people have at least one episode of mental illness during their lifetime.”


What compels people to manufacture “universal” truths? Is this a poor substitute for feeling and understanding historical, factual, personal truths?

What if the price we pay for avoiding and pressuring down our feelings is: A wasted life?

What if the grand hypothesis worth proving is: For one’s life to have meaning, each individual has to regain their feelings?

Fitting data

Let’s start out the new year with a repost of a cautionary reminder:

“Both “predict and “explain” imply that investigators have uncovered a reliable structure to phenomena, the latter involving hypotheses describing unseen mechanisms, leading to a new ability to control events and produce formerly unpredicted/unpredictable outcomes. This is clearly not a fair description of post hoc correlation-fishing.

The current publication system almost forces authors to make causal statements using filler verbs (e.g. to drive, alter, promote) as a form of storytelling (Gomez-Marin, 2017); without such a statement they are often accused of just collecting meaningless facts.”

https://mythsofvisionscience.wordpress.com/2018/12/30/neuroscience-newspeak-or-how-to-publish-meaningless-facts/ “Neuroscience Newspeak, Or How to Publish Meaningless Facts”