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 adverselyimpact 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 that remains to be examined is: How can humans best address these early-life causes to ameliorate their lifelong effects?
This 2018 human study presented the results of 100 patients’ personalized therapies for cognitive decline:
“The first examples of reversal of cognitive decline in Alzheimer’s disease and the pre-Alzheimer’s disease conditions MCI (Mild Cognitive Impairment) and SCI (Subjective Cognitive Impairment) have recently been published..showing sustained subjective and objective improvement in cognition, using a comprehensive, precision medicine approach that involves determining the potential contributors to the cognitive decline (e.g., activation of the innate immune system by pathogens or intestinal permeability, reduction in trophic or hormonal support, specific toxin exposure, or other contributors), using a computer-based algorithm to determine subtype and then addressing each contributor using a personalized, targeted, multi-factorial approach dubbed ReCODE for reversal of cognitive decline.
An obvious criticism of the initial studies is the small number of patients reported. Therefore, we report here 100 patients, treated by several different physicians, with documented improvement in cognition, in some cases with documentation of improvement in electrophysiology or imaging, as well.”
“We have a paper in press, due to appear 10.22.18 (open access, JADP, I’ll send a copy as soon as available), showing 100 patients with documented improvement – some with MRI volumetrics improved, others with quantitative EEG improvements, others with evoked response improvements, and all with quantitative cognitive assessment improvement. Some are very striking – 12 point improvements in MoCA, for example – others less so, but all also have subjective improvement. Hopefully this will address some of the criticisms that we haven’t documented improvement in enough people.
We were just turned down again for a randomized, controlled clinical trial, so on the one hand, we are told repeatedly that no one will believe that this approach works until we publish a randomized, controlled study, and on the other hand, we’ve been turned down (first in 2011/12, and now in 2018), with the complaint that we are trying to address more than one variable in the trial (as if AD is a single-variable disease!). Something of a catch-22. We are now resubmitting (unfortunately, the IRBs are not populated by functional medicine physicians, so they are used to seeing old-fashioned drug studies), and we’ll see what happens.
I’ve been extending the studies to other neurodegenerative diseases, and it has been impressive how much of a programmatic response there seems to be in these “diseases.”
I agree with you that there are many features in common with aging itself.
You made a good point that APP is a dependence receptor, and in fact it functions as an integrating dependence receptor, responding to numerous inputs (Kurakin and Bredesen, 2015).
In the book and the publications, we don’t claim it is a “cure” since we don’t have pathological evidence that the disease process is gone. What we claim is “reversal of cognitive decline” since that is what we document.
As I mentioned in the book, AD is turning out to be a protective response to multiple insults, and this fits well with the finding that Abeta has an antimicrobial effect (Moir and Tanzi’s work). It is a network-downsizing, protective response, which is quite effective – some people live with the ongoing degenerative process for decades.
We have seen several cases now in which a clinical trial of an anti-amyloid antibody made the person much worse in a time-dependent manner (each time there was an injection, the person would get much worse for 5-10 days, then begin to improve back toward where he/she was, but over time, marked decline occurred), and this makes sense for the idea that the amyloid is actually protecting against pathogens or toxins or some other insult.
It is important to note that we’ve never claimed that all people get better – this is not what we’ve seen. People very late in the process, or who don’t follow the protocol, or who don’t address the various insults, do not improve. It is also turning out to be practitioner dependent – some are getting the vast majority of people to improve, others very few, so this is more like surgery than old-fashioned prescriptive medicine – you have to do a somewhat complicated therapeutic algorithm and get it right for best results.
I’m very interested in what is needed to take the next step in people who have shown improvement but who started late in the course. For example, we have people now who have increased MoCA from 0 to 9 (or 0 to 3, etc.), with marked subjective improvement but plateauing at less than normal. These people had extensive synaptic and cellular loss prior to the program. So what do we need to raise the plateau? Stem cells? Intranasal trophic support? Something else?
I haven’t yet seen a mono-etiologic theory of AD or a mono-therapeutic approach that has repeatedly positive results, so although I understand that there are many theories and treatments, there doesn’t seem to be one etiology to the disease, nor does there seem to be one simple treatment that works for most. It is much more like a network failure.”
At a specific level:
“There doesn’t seem to be one etiology to the disease,
nor does there seem to be one simple treatment that works for most.
We don’t have pathological evidence that the disease process is gone.”
For general concepts, however:
“AD is turning out to be a protective response to multiple insults,
It is a network-downsizing, protective response, which is quite effective.
The amyloid is actually protecting against pathogens or toxins or some other insult.”
For a framework of an AD cure to be valid, each source of each insult that evoked each “protective response” should be traced.
Longitudinal studies would be preferred inside this framework. These study designs would investigate evidence of each insult’s potential modifying effect on each “protective response” that could affect the cumulative disease trajectory of each individual.
In many cases, existing study designs would be adequate if they extended their periods to the end of the subjects’ natural lifetimes. One AD-relevant example would be extending the prenatally-restraint-stressed model used in:
This 2017 UC Irvine human review subject provided details of how fetalhypothalamic-pituitary-adrenal components and systems develop, and how they are epigenetically changed by the mother’s environment:
“The developmental origins of disease or fetal programming model predicts that intrauterine exposures have life-long consequences for physical and psychological health. Prenatal programming of the fetal hypothalamic-pituitary-adrenal (HPA) axis is proposed as a primary mechanism by which early experiences are linked to later disease risk.
Development of the fetal HPA axis is determined by an intricately timed cascade of endocrine events during gestation and is regulated by an integrated maternal-placental-fetal steroidogenic unit. Mechanisms by which stress-induced elevations in hormones of maternal, fetal, or placental origin influence the structure and function of the emerging fetal HPA axis are discussed.
Human gestational physiology and fetal HPA axis development differ even from that of closely related nonhuman primates, thereby limiting the generalizability of animal models. This review will focus solely on studies of prenatal stress and fetal HPA axis development in humans.”
Every time I read a prenatal study I’m in awe of all that has to go right, and at the appropriate time, and in sequence, for a fetus to be undamaged. Add in what needs to happen at birth, during infancy, and throughout early childhood, and it seems impossible for any human to escape epigenetic damage.
1. The reviewers referenced human research performed with postnatal subjects, as well as animal studies, despite the disclaimer:
This review will focus solely on studies of prenatal stress and fetal HPA axis development in humans.”
This led to blurring of what had been studied or not with human fetuses regarding the subject.
2. The reviewers uncritically listed many dubious human studies that had both stated and undisclosed severe limitations on their findings. It’s more appropriate for reviewers to offer informed reviews of cited studies, as Sex-specific impacts of childhood trauma summarized with cortisol:
“Findings are dependent upon variance in extenuating factors, including but not limited to, different measurements of:
presence and severity of psychopathology symptomology.”
3. It would have been preferable had the researchers stayed with their stated intention and critically reviewed only a few dozen studies with solid evidence of the review title: “Developmental origins of the human hypothalamic-pituitary-adrenal axis.” Let other reviews cover older humans, animals, and questionable evidence.
I asked the reviewers to provide a searchable file so that their work could be better used as a reference.
This 2018 German review was comprehensive for its subject, epigenetic control of variation and stochasticity in metabolic disease. I’ll focus on one aspect, phenotypic variation:
“Phenotypic [Mendelian] variation can result both from gain- and loss-of-function mutations. 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.
∼98.5% of our genome is non-protein-coding: it is pervasively transcribed, and its transcripts can support regulatory function. Among the best functionally characterized non-coding RNAs (ncRNAs) arising from these sequences are microRNAs (miRNAs).
Environmental [non-Mendelian] variation or ‘stimuli’ occurring during critical windows of susceptibility can elicit lifelong alterations in an individual’s phenotype. Intergenerational metabolic reprogramming [in fruit flies] results from global alterations in chromatin state integrity, particularly from reduced H3K27me3 and H3K9me3 [histone] domains.
The broad variation of fingerprints in humans is thought to depend to a large degree on stochastic variation in mechanical forces. These clear examples of inducible multi-stable or stochastic variation highlight how little we know about the landscape of potential phenotypic variation itself.
Consensus estimates of heritability for obesity and T2D are ∼70% and ∼35% respectively. The remaining, unexplained component is known to involve gene–environment interactions as well as non-Mendelian players.”
Although the above graphic displays transgenerational inheritance for humans, the reviewers didn’t cite any human studies that adequately demonstrated causes for and effects of transgenerational epigenetic inheritance.
I’ve read the cited Swedish and Dutch studies. Their designs, methods, and “correlate with” / “was associated with” results didn’t provide incontrovertible evidence from the F0 great-grandparents, F1 grandparents, F2 parents, and F3 children. It’s necessary to thoroughly study each generation to confirm definitive transgenerational epigenetic inheritance causes and effects.
I downgraded the review for treating research of this and other subjects as faits accomplis. It’s opposite ends of the evidential spectrum to state “how little we know about the landscape of potential phenotypic variation,” and in the same review, speciously extrapolate animal experiments into putative human results.
The study’s non-statistical data was almost all unverified self-reports by a self-selected sample of the F2 grandchildren, average age 37.
No detailed physical measurements or samples were taken of them, or of their F1 parents, or of their F0 grandparents, all of which are required as baselines for any transgenerational epigenetic inheritance findings.
No detailed physical measurements or samples were taken of their F3 children, which is the generation that may provide transgenerational evidence if the previous generations also have detailed physical baselines.
The study’s researchers drew enough participants (360) such that their statistics package allowed them to impute and assume into existence a LOT of data. But the scientific method constrained them to make factual statements of what the evidence actually showed. They admitted:
“In conclusion, we did not find a transgenerational effect of prenatal famine exposure on the health of grandchildren in this study.”
Yet this study is somehow cited for evidence of human transgenerational epigenetically inherited causes and effects.
This 2017 Massachusetts human review described one example of psychological research continuing to misinterpret measurements for hypotheses that have been rejected for physiological research:
“The current paper is a case study examining what happens to psychological research when its foundational biological context is invalidated or superseded. The example we use is heart rate variability (HRV) as a purported measure of cardiac sympathetic outflow.
The hypotheses in question are of direct relevance to fields including biological psychology, psychophysiology, and social neuroscience that use physiological measurements to answer applied questions with broader social scientific relevance. A broad base of further evidence was amassed within human cardiac, circulatory, and autonomic physiology such that the hypotheses do not work as described.
These were important and popular metrics, they attracted appropriate scrutiny, and were subsequently discarded. The above reflects well on the scientific process within basic research. The present ensuing period of ‘life after death’ within applied research does not.
It has been widely used as a dependent variable in studies of emotion, panic, stress, attentional state, health status in psychological science.
If the criteria for publishing a scientific article is simply that the measured results resolve to be statistically significant, an unstable measurement of an unstable phenomenon is an excellent vehicle for engineering differences between groups, especially considering the substantial flexibility in modern publication practices.”
Factors facilitating the misinterpretation of heart rate variability include:
Measurements are convenient and inexpensive (like salivary cortisol):
“HRV measurement lacks barriers to collection – measurement is possible during movement and activities of daily living, is easily capable of taking multiple sequential measurements without participant fatigue, and is suitable for long-term recordings. It is also inexpensive, due to multiple commercially available hardware platforms and free software analysis programs.”
The experimental concept is easily explained to sponsors.
This 2018 Loma Linda review subject was gestational hypoxia:
“Of all the stresses to which the fetus and newborn infant are subjected, perhaps the most important and clinically relevant is that of hypoxia. This review explores the impact of gestational hypoxia on maternal health and fetal development, and epigenetic mechanisms of developmental plasticity with emphasis on the uteroplacental circulation, heart development, cerebral circulation, pulmonary development, and the hypothalamic-pituitary-adrenal axis and adipose tissue.
An understanding of the specific hypoxia-induced environmental and epigenetic adaptations linked to specific organ systems will enhance the development of target-specific inhibition of DNA methylation, histone modifications, and noncoding RNAs that underlie hypoxia-induced phenotypicprogramming of disease vulnerability later in life.
A potential stumbling block to these efforts, however, relates to timing of the intervention. The greatest potential effect would be accomplished at the critical period in development for which the genomic plasticity is at its peak, thus ameliorating the influence of hypoxia or other stressors.
With future developments, it may even become possible to intervene before conception, before the genetic determinants of the risk of developing programmed disease are established.”
Table 3 “Antenatal hypoxia and developmental plasticity” column titles were Species | Offspring Phenotypes of Disorders and Diseases | Reference Nos.
This review was really an ebook, with 94 pages and 1,172 citations in the pdf file. As I did with Faith-tainted epigenetics, I read it with caution toward recognizing 1) the influence of the sponsor’s biases, 2) any directed narrative that ignored evidence contradicting the narrative, and 3) any storytelling.
One review topic that was misconstrued was transgenerational epigenetic inheritance of hypoxic effects. The “transgenerational” term was used inappropriately by several of the citations, and no cited study provided evidence for gestational hypoxic effects through the F2 grandchild and F3 great-grandchild generations.
“One substance that fetuses are frequently exposed to is caffeine, which is a non-selective adenosine receptor antagonist. We discovered that in utero alteration in adenosine action leads to adverse effects on embryonic and adult murine hearts. We find that cardiac A1ARs [a type of adenosine receptor] protect the embryo from in utero hypoxic stress, a condition that causes an increase in adenosine levels.
After birth in mice, we observed that in utero caffeine exposure leads to abnormal cardiac function and morphology in adults, including an impaired response to β-adrenergic stimulation. Recently, we observed that in utero caffeine exposure induces transgenerational effects on cardiac morphology, function, and gene expression.”
Why was this review and its studies omitted? It was on target for both gestational hypoxia and transgenerational epigenetic inheritance of hypoxic effects!
It was alright to review smoking, cocaine, methamphetamine, etc., but the most prevalent drug addiction – caffeine – couldn’t be a review topic?
The Loma Linda review covered a lot, but I had a quick trigger due to the sponsor’s bias. I started to lose “faith” in the reviewers after reading the citation for the review’s last sentence that didn’t support the statement.
My “faith” disappeared after not understanding why a few topics were misconstrued and omitted. Why do researchers and sponsors ignore, misrepresent, and not continue experiments through the F3 generation to produce evidence for and against transgenerational epigenetic inheritance? Where was the will to follow evidence trails regardless of socially acceptable beverage norms?
The review acquired the taint of storytelling with the reviewers’ assertion:
“..timing of the intervention. The greatest potential effect would be accomplished at the critical period in development for which the genomic plasticity is at its peak, thus ameliorating the influence of hypoxia or other stressors.”
Contradictory evidence was in the omitted caffeine study’s graphic above which described two gestational critical periods where an “intervention” had opposite effects, all of which were harmful to the current fetus’ development and/or to following generations. Widening the PubMed link’s search parameters to “caffeine hypoxia” and “caffeine pregnancy” returned links to human early life studies that used caffeine in interventions, ignoring possible adverse effects on future generations.
This is my final curation of any paper sponsored by this institution.