Epigenetic transgenerational inheritance of ovarian disease

This 2018 Washington rodent study investigated ovarian disease in F3 great-granddaughters caused by their F0 great-grandmothers’ exposures to DDT or vinclozolin while pregnant:

“Two of the most prevalent ovarian diseases affecting women’s fertility and health are Primary Ovarian Insufficiency (POI) and Polycystic Ovarian Syndrome (PCOS). POI is characterized by a marked reduction in the primordial follicle pool of oocytes and the induction of menopause prior to age 40. POI currently affects approximately 1% of female population. While genetic causes can be ascribed to a minority of patients, around 90% of POI cases are considered idiopathic, with no apparent genetic link nor known cause.

PCOS is a multi-faceted disease that affects 6-18% of women. It is characterized by infrequent ovulation or anovulation, high androgen levels in the blood, and the presence of multiple persistent ovarian cysts.

For both PCOS and POI other underlying causes such as epigenetic transgenerational inheritance of disease susceptibility have seldom been considered. Epigenetic transgenerational inheritance is defined as “the germline transmission of epigenetic information and phenotypic change across generations in the absence of any continued direct environmental exposure or genetic manipulation.” Epigenetic factors include:

    • DNA methylation,
    • Histone modifications,
    • Expression of noncoding RNA,
    • RNA methylation, and
    • Alterations in chromatin structure.

The majority of transgenerational studies have examined sperm transmission of epigenetic changes due to limitations in oocyte numbers for efficient analysis.

There was no increase in ovarian disease in direct fetal exposed F1 [grandmothers] or germline exposed F2 [mothers] generation vinclozolin or DDT lineage rats compared to controls.

F3 generation ovarian disease

The transgenerational molecular mechanism is distinct and involves the germline (sperm or egg) having an altered epigenome that following fertilization may modify the embryonic stem cells epigenome and transcriptome. This subsequently impacts the epigenetics and transcriptome of all somatic cell types derived from these stem cells.

Therefore, all somatic cells in the transgenerational [F3] animal have altered epigenomes and transcriptomes and those sensitive to this alteration will be susceptible to develop disease. The F3 generation can have disease while the F1 and F2 generations do not, due to this difference in the molecular mechanisms involved.

The epimutations and gene expression differences observed are present in granulosa cells in the late pubertal female rats at 22-24 days of age, which is long before any visible signs of ovarian disease are detectable. This indicates that the underlying factors that can contribute to adult-onset diseases like PCOS and POI appear to be present early in life.

Ancestral exposure to toxicants is a risk factor that must be considered in the molecular etiology of ovarian disease.”


1. The study highlighted a great opportunity for researchers of any disease that frequently has an “idiopathic” diagnosis. It said a lot about research priorities that “around 90% of POI cases are considered idiopathic, with no apparent genetic link nor known cause.”

It isn’t sufficiently explanatory for physicians to continue using categorization terminology from thousands of years ago. Science has progressed enough with measured evidence to discard the “idiopathic” category and express probabilistic understanding of causes.

2. One of this study’s coauthors made a point worth repeating in The imperative of human transgenerational studies: What’s keeping researchers from making a significant difference in their fields with human epigenetic transgenerational inheritance studies?

3. Parts of the study’s Discussion section weren’t supported by its evidence. The study didn’t demonstrate:

  • That “all somatic cells in the transgenerational animal have altered epigenomes and transcriptomes”; and
  • The precise “molecular mechanisms involved” that exactly explain why “the F3 generation can have disease while the F1 and F2 generations do not.”

https://www.tandfonline.com/doi/abs/10.1080/15592294.2018.1521223 “Environmental Toxicant Induced Epigenetic Transgenerational Inheritance of Ovarian Pathology and Granulosa Cell Epigenome and Transcriptome Alterations: Ancestral Origins of Polycystic Ovarian Syndrome and Primary Ovarian Insuf[f]iency” (not freely available)

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The imperative of human transgenerational studies

The coauthor of:

pointed out the opportunity for the researchers of A seasonal epigenetic effect of conception on BMI to have their work make a difference in their field:

“The ability of environmental epigenetics to promote an adaptive phenotype to cold has impacts on evolution. However, the impacts would be far greater if the phenomenon was transgenerational.

Future studies are now needed to determine whether the cold-induced thrifty metabolic phenotype is transmitted to subsequent generations. If exposure not only impacts the health of offspring, but also of all subsequent generations, the impact is significant.”


Every human alive today has observable lasting epigenetic effects caused by environmental factors:

  • During the earliest parts of our lives;
  • From our parents’ exposures and experiences before we’re conceived – many of which are inadequately researched; and
  • Potentially from some of our earlier ancestors’ exposures and experiences.

Aren’t animal studies’ evidence for epigenetic transgenerational inheritance sufficient to compel serious human follow-on research efforts by research sponsors and study designers?

The same comments about epigenetic effects caused by temperature potentially inherited by multiple human generations can also be made about other environmental factors, such as:

  • Nutrition,
  • Toxins – the commentator’s usual area of study, and
  • Stress.

I hope that these researchers value their professions enough to make a difference with this or other areas of their expertise. And that sponsors won’t thwart researchers’ desires for difference-making science by putting them into endless funding queues.

https://www.nature.com/articles/s41591-018-0187-3 “Preconception cold-induced epigenetic inheritance” (not freely available)

Reversing epigenetic changes with CRISPR/Cas9

This 2018 Chinese review highlighted areas in which CRISPR/Cas9 technology has, is, and could be applied to rewrite epigenetic changes:

“CRISPR/Cas9-mediated epigenome editing holds a great promise for epigenetic studies and therapeutics.

It could be used to selectively modify epigenetic marks at a given locus to explore mechanisms of how targeted epigenetic alterations would affect transcription regulation and cause subsequent phenotype changes. For example, inducing histone methylation or acetylation at the Fosb locus in the mice brain reward region, nucleus accumbens, could affect relevant transcription network and thus control behavioral responses evoked by drug and stress.

Epigenome editing has the potential for epigenetic treatment, especially for the disorders with abnormal gene imprinting or epigenetic marks. Targeted epigenetic silencing or reactivation of the mutant allele could be a potential therapeutic approach for diseases such as Rett syndrome and Huntington’s disease.

Noncoding RNA plays important roles in gene imprinting and chromatin remodeling. CRISPR/Cas9 has been shown to be potential for manipulating noncoding RNA expression, including microRNA, long noncoding RNA, and miRNA families and clusters.

In vivo overexpression of the Yamanaka factors have proven to be able to fully or partially help somatic cells to regain pluripotency in situ. These rejuvenated cells would subsequently differentiate again to replace the lost cell types.”


The last paragraph was described in The epigenetic clock theory of aging as a promising technique:

“To date, the most effective in vitro intervention against epigenetic ageing is achieved through expression of Yamanaka factors, which convert somatic cells into pluripotent stem cells, thereby completely resetting the epigenetic clock.”

The reviewers cited three references for in vivo studies of this technique. Overall, I didn’t see that any of the review’s references were in vivo human studies.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6079388/ “Novel Epigenetic Techniques Provided by the CRISPR/Cas9 System”

Epigenetic factors affecting female rat sexual behavior

This 2018 Baltimore/Montreal rodent study found:

“If sexually naïve females have their formative sexually rewarding experiences paired with the same male, they will recognize that male and display mate-guarding behavior towards him in the presence of a female competitor. Female rats that display mate-guarding behavior also show enhanced activation of oxytocin and vasopressin neurons in the supraoptic and paraventricular hypothalamic nucleus.

We examined the effect of a lysine-specific demethylase-1 inhibitor to block the action of demethylase enzymes and maintain the methylation state of corresponding genes. Female rats treated with the demethylase inhibitor failed to show any measure of mate guarding, whereas females treated with vehicle displayed mate guarding behavior. Demethylase inhibitor treatment also blocked the ability of familiar male cues to activate oxytocin and vasopressin neurons, whereas vehicle-treated females showed this enhanced activation.”

General principles and their study-specific illustrations were:

Histone modifications are a key element in gene regulation through chromatin remodeling. Histone methylation / demethylation does not have straightforward transcriptional outcomes as do other histone modifications, like acetylation, which is almost invariably associated with transcriptional activation.

What is of vital importance in regards to histone methylation / demethylation is the pattern of methylation that is established. Patterns of methylation incorporate both methylated and demethylated residues, and are what ultimately play a role in transcriptional outcomes.

In the present study, inhibiting LSD1 demethylase enzymes disrupted the ability of cells to properly establish histone methylation / demethylation patterns, thus creating a deficit in the cells’ ability to transcribe the gene products necessary for the enhanced induction of OT, AVP, and the subsequent mate-guarding behaviors we observed. This study is the first to demonstrate a definitive role of epigenetic histone modifications in a conditioned sexual response.”

https://www.sciencedirect.com/science/article/pii/S0031938418303421 “Inhibition of lysine-specific demethylase enzyme disrupts sexually conditioned mate guarding in the female rat” (not freely available)

Organ epigenetic memory

This 2018 Japanese review subject was the relationships of organ memory and non-communicable diseases:

“Organ memory is the engraved phenotype of altered organ responsiveness acquired by a time-dependent accumulation of organ stress responses. This phenomenon is known as “metabolic memory” or “legacy effect,” which is similar to neuronal and immune memory.

Not only is the epigenetic change of key genes involved in the formation of organ memory but the alteration of multiple factors, including low molecular weight energy metabolites, immune mediators, and tissue structures, is involved as well. These factors intercommunicate during every stress response and carry out incessant remodeling in a certain direction in a spiral fashion through positive feedback mechanisms.

The systematic review revealed that each intervention type, that is:

  • Glucose lowering,
  • Blood pressure lowering, or
  • LDL-cholesterol lowering,

possessed unique characteristics of the memory phenomenon. Most of the observational periods of these studies lasted for > 10 years. Memory phenomenon was suggested to last for a long time and is thought to have a considerable effect on the clinical course of NCDs [non-communicable diseases].

Organs cannot possess consciousness, so it might not be appropriate to consider whether a recalling process exists in organs. However, the properties of organs are incessantly altered by external stimuli loaded on organs as if it is updating.

It is clinically important to investigate whether organ memory can be updated by our behaviors. Once organ memory is established in an organ, organ memory in each organ can influence one another and affect organ memory in a different organ.

Epigenome-modification enzymes, such as histone deacetylases and DNA methyltransferases, and transcription factors seem to be essential for the epigenetic regulation of gene expression, which is involved in the generation of organ memory. Cellular metabolism can epigenetically modulate the expression of genes that are related to the progression of diseases.”


1. The reviewers asserted:

“Organs cannot possess consciousness, so it might not be appropriate to consider whether a recalling process exists in organs.”

Memory studies don’t require this consciousness to investigate even the brain organ’s areas and functions. Researchers observe memory by measuring stimulus/response items like neuron activation and various levels of behavior. Consciousness is an emergent property.

2. Regarding recall: An organ’s “engraved phenotype of altered organ responsiveness” may not have recall itself, but it doesn’t have a separate existence apart from its body. An organ can’t be removed from its body for very long and still be part of its body.

When an organ is in its normal state as part of a body, it has access to recall-like functions via the “inter-organ communication of organ memory.” The review also mentioned:

“Organ memory in each organ can influence one another and affect organ memory in a different organ.

Evolution didn’t support unnecessary duplication for a kidney’s memory to include recall because it’s part of a body that includes a brain that has recall. Evolution didn’t duplicate functions of a kidney’s memory in a brain, either.

https://www.nature.com/articles/s41440-018-0081-x “Organ memory: a key principle for understanding the pathophysiology of hypertension and other non-communicable diseases” (not freely available)

Unindexed comment links?

It’s dawned on me that although links in blog posts are indexed by search engines, links in comments may not be. Here’s a post to elevate links in three comments that may have escaped notice.


From A review of biological variability:

“It is my view that all researchers have a narrow focus on what they want to research, without having an over-riding paradigm in which to fit the research and its results. Janovian Primal Therapy and theory, with its focus and understanding of the three different levels of consciousness would provide for a much needed over-arching paradigm, especially in the area of mental health.”

Congratulations on an excellent podcast, Gil!
59. Gilbert Bates in “Feel It Still” // Love, Primal Therapy & the Three Levels of Consciousness


From Remembering Dr. Arthur Janov:

“You are right on. The Norcross survey, in particular, is utter crap. More than half of those “experts” surveyed were CBT therapists who knew nothing about PT and yet deemed themselves confident to judge “primal scream therapy” as “discredited.” I feel the therapy will never be understood for what it is.”

Thanks for the detailed explanation, Bruce!
The Worst Comparative Psychotherapy Study Ever Published


From How one person’s paradigms regarding stress and epigenetics impedes relevant research:

“There is of course, reversibility. Michael Meaney’s baby rats had their epigenetic changes reversed with loving maternal care. There are several compounds in development which have been shown to reverse methylation. This former physician and researcher says, “Epigenetic changes affect the level of activity of our genes. Genetic activity levels affect our emotions, beliefs, and our bodies. Exploring epigenetics and chronic illness may help us understand causes that many of us suspect have played a role in the onset and evolution of our illnesses. Furthermore, these epigenetic changes have been found to be reversible, at least some of the time, even with a seemingly indirect treatment such as psychotherapy.” Epigenetics and Chronic Illness: Why Symptoms May Be Reversible

I looked up the psychotherapy references and found this: Serotonin tranporter methylation and response to cognitive behaviour therapy in children with anxiety disorders (reversible even with CBT, the weakest therapy of all!)

And this:
MAOA gene hypomethylation in panic disorder—reversibility of an epigenetic risk pattern by psychotherapy (also CBT)

So what gives? I suspect that your researcher is working with his/her head in the sand, hamstrung by their ideological biases. If CBT can effect epigenetic changes, imagine what primal therapy can do.”


And a seven-year anniversary repost of events that affect me every day:

Reflections on my four-year anniversary of spine surgery

Restoration of a “normal” epigenetic landscape

This 2018 Texas human review subject was prostate cancer epigenetics:

“We comprehensively review the up-to-date roles of epigenetics in the development and progression of prostate cancer. We especially focus on three epigenetic mechanisms: DNA methylation, histone modifications, and noncoding RNAs. We elaborate on current models/theories that explain the necessity of these epigenetic programs in driving the malignant phenotypes of prostate cancer cells.

It is now generally accepted that epigenetics contributes to the development of nearly every stage of PCa [prostate cancer]. Considering the highly heterogeneous nature of PCa, it is quite likely that [the] effect of a particular epigenetic pattern on growth of cancer cells varies from case to case and [is] context specific.

Restoration of a “normal” epigenetic landscape holds promise as a cure for prostate cancer.”

The review’s Epigenetic Therapy section explained much of what’s going on in the above graphic. Its Table 3 was instructive for up-to-date clinical trial information on epigenetic treatments of prostate cancer.


“Restoration of a “normal” epigenetic landscape” won’t guarantee a healthy outcome once diseases start. Prevention seems desirable to avoid the situation where:

“Numerous epigenetic alterations reinforce the establishment of a context-specific transcriptional profile that favors self-renewal, survival, and invasion of PCa cells.”

http://www.ajandrology.com/article.asp?issn=1008-682X;year=2019;volume=21;issue=3;spage=279;epage=290;aulast=Liao “Epigenetic regulation of prostate cancer: the theories and the clinical implications”