Do epigenetic clocks measure causes or effects?

The founder of the PhenoAge epigenetic clock methodology authored this 2020 article: “The Ge[r]oscience paradigm suggests that targeting the aging process could delay or prevent the risk of multiple major age-related diseases. We need clinically valid measures of the underlying biological process and/or classification criteria for what it means to be biologically, rather than chronologically, … Continue reading Do epigenetic clocks measure causes or effects?

A blood plasma aging clock

This 2019 Stanford human study developed an aging clock using blood plasma proteins: “We measured 2,925 plasma proteins from 4,331 young adults to nonagenarians [18 – 95] and developed a novel bioinformatics approach which uncovered profound non-linear alterations in the human plasma proteome with age. Waves of changes in the proteome in the fourth, seventh, … Continue reading A blood plasma aging clock

Preliminary findings from a senolytics clinical trial

This 2019 US human clinical trial reported preliminary results. See Reanalysis of findings from a senolytics clinical trial for strikeout changes. “Senescent cells, which can release factors that cause inflammation and dysfunction, the senescence-associated secretory phenotype (SASP), accumulate with ageing and at etiological sites in multiple chronic diseases. Senolytics, including the combination of Dasatinib and … Continue reading Preliminary findings from a senolytics clinical trial

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 … Continue reading Reversal of aging and immunosenescent trends

What drives cellular aging?

This 2019 US/UK human cell study by the founder of the epigenetic clock method investigated epigenetic aging: “It is widely assumed that extension of lifespan is a result of retardation of ageing. While there is no counter-evidence to challenge this highly intuitive association, supporting empirical evidence to confirm it is not easy to acquire. The … Continue reading What drives cellular aging?

Epigenetic clock statistics and methods

This 2018 Chinese study was a series of statistical and methodological counter-arguments to a previous epigenetic clock study finding that: “Only [CpG] sites mapping to the ELOVL2 promoter constitute cell and tissue-type independent aDMPs [age-associated differentially methylated positions].” The study used external data sets and the newer epigenetic clock’s fibroblast data in its analyses to … Continue reading Epigenetic clock statistics and methods

Epigenetic effects of breast cancer treatments

This 2018 UC San Diego review subject was the interplay between breast cancer treatments and their effects on aging: “Although current breast cancer treatments are largely successful in producing cancer remission and extending lifespan, there is concern that these treatments may have long lasting detrimental effects on cancer survivors, in part, through their impact on … Continue reading Epigenetic effects of breast cancer treatments

The epigenetic clock theory of aging

My 400th curation is a 2018 US/UK paper by two of the coauthors of Using an epigenetic clock to distinguish cellular aging from senescence. The authors reviewed the current state of epigenetic clock research, and proposed a new theory of aging: “The proposed epigenetic clock theory of ageing views biological ageing as an unintended consequence … Continue reading The epigenetic clock theory of aging

The purpose of epigenetic mechanisms

The concluding remarks of this 2018 Chinese review were: “Using heterochromatin as a model, we have reviewed here the mechanisms behind the establishment and maintenance of silent chromatin domains. We conclude that almost every component of the chromatin environment, including DNA elements, RNAs, histones and other chromatin proteins, plays a role in the process of … Continue reading The purpose of epigenetic mechanisms

The influence of donor age on induced pluripotent stem cell functionality

This 2018 German review subject was the influence of donor age on induced pluripotent stem cell functionality: “Induced pluripotent stem cells (iPSCs) avoid many of the restrictions that hamper the application of human embryonic stem cells. Also, the donor’s clinical phenotype is often known when working with iPSCs. Typical signs of cellular ageing are reverted … Continue reading The influence of donor age on induced pluripotent stem cell functionality

Epigenetic mechanisms regulate bone growth

This 2017 Baltimore/China rodent study found: “MSPC [Mesenchymal stem/progenitor cell] senescence is epigenetically controlled by the polycomb histone methyltransferase enhancer of zeste homolog 2 (Ezh2) and its trimethylation of histone H3 on Lysine 27 (H3K27me3) mark. Ezh2 maintains the repression of key cell senescence inducer genes through H3K27me3. Our work establishes the role of Ezh2-H3K27me3 … Continue reading Epigenetic mechanisms regulate bone growth

Epigenetic effects of cruciferous vegetable compounds

This 2017 German review discussed the results of many of the studies performed over the past thirty years investigating the health-promoting effects of cruciferous vegetable compounds: “SFN [sulforaphane] [is] the ITC [isothiocyanate] that is the most extensively studied for its chemopreventive and anti-inflammatory properties in vitro, as well as in vivo. Due to the reversible … Continue reading Epigenetic effects of cruciferous vegetable compounds

Lack of oxygen’s epigenetic effects

This 2016 Finnish review subject was the epigenetic effects of hypoxia: “Ever since the Cambrian period, oxygen availability has been in the center of energy metabolism. Hypoxia stabilizes the expression of hypoxia-inducible transcription factor-1α (HIF-1α), which controls the expression of hundreds of survival genes related to enhanced energy metabolism and autophagy. There are several other … Continue reading Lack of oxygen’s epigenetic effects

The current paradigm of child abuse limits pre-childhood causal research

As an adult, what would be your primary concern if you suspected that your early life had something to do with current problems? Would you be interested in effective treatments for causes of your symptoms? Such information wasn’t available in this 2016 Miami review of the effects of child abuse. The review laid out the … Continue reading The current paradigm of child abuse limits pre-childhood causal research

Using an epigenetic clock with older adults

This 2016 German human study found: “Epigenetic age acceleration is correlated with clinically relevant aging-related phenotypes through pathways unrelated to cellular senescence as assessed by telomere length. The current work employed the frailty index, a multi-dimensional approach that combines [34] parameters of multiple physiological systems and functional capacities. The present findings were based on [1,820] … Continue reading Using an epigenetic clock with older adults