Category: Misha Blagosklonny

No comments

Can a Daily Dose of Electricity Improve Aging?

  By

Researchers from the University of Leeds and the University of Glasgow conducted a 2019 study on the effects of transcutaneous vagal nerve stimulation (tVNS) among participants 55 years of age and older.

Medical illustration of vagus nerve with brain, lungs, heart, stomach and digestive tract.
Medical illustration of vagus nerve with brain, lungs, heart, stomach and digestive tract.

The Top-Performer series highlights papers published by Aging that have generated a high Altmetric attention score. Altmetric scores, located at the top-left of trending Aging papers, provide an at-a-glance indication of the volume and type of online attention the research has received.

Read Aging’s Top 100 Altmetric papers.

—

Listen to an audio version of this article

Among the cranial nerves, the vagus nerve has the largest distribution in the body. Extending from the brain to the abdomen, its name is derived from the Latin word vagari—which means “to wander.” This wandering nerve serves as part of the involuntary, or autonomic, nervous system. The vagus nerve is responsible for a number of important autonomic bodily functions, including lung function, heart rate, inflammation, brain/gut communication, mood, and even the consolidation of memories. 

Human aging is accompanied by progressive autonomic changes, including increases in sympathetic nervous activity (“fight or flight” responses) and decreases in parasympathetic nervous activity (“rest and digest” responses). These changes can have considerable effects on heart function, emotion, mood, gut function, and overall quality of life, and can often lead to an increase in medication consumption with age. 

TRANSCUTANEOUS VAGAL NERVE STIMULATION (TVNS)

In efforts to boost parasympathetic activity and decrease sympathetic activity, interventions such as vagus nerve stimulation (VNS) and transcutaneous vagal nerve stimulation (tVNS) have been developed. VNS is a highly invasive intervention, which involves surgically implanting an electrode around the cervical vagus nerve and a generator unit in the thoracic wall. Researchers have found that the non-invasive tVNS therapy (an electrical pulse focused on the tragus of the outer ear) is a safer and simpler intervention. Positive effects on autonomic function have been reported in non-patient groups treated with tVNS.

“tVNS is a simple, non-invasive and inexpensive therapy that involves stimulating the auricular branch of the vagus nerve (ABVN) at outer parts of the ear, conferring autonomic benefits in healthy volunteers [10].”

Previous research has shown that tVNS significantly reduces sympathetic nerve activity in healthy participants and boosts measures of parasympathetic activity. However, there are few studies available which detail the effects of tVNS in healthy older participants. 

“Despite this evidence, there is little work examining the autonomic implications of administering tVNS in healthy older individuals who are undergoing age-associated shifts towards sympathetic prevalence.”

THE STUDY

In 2019, researchers from the United Kingdom’s University of Leeds and University of Glasgow reported on the results of the effects of tVNS among participants 55 years of age and older in three studies. Their paper was published in Aging’s Volume 11, Issue 14, and entitled: “Effects of transcutaneous vagus nerve stimulation in individuals aged 55 years or above: potential benefits of daily stimulation.” To date, this research paper has received an impressive Altmetric Attention score of 350.

In the first study, the researchers observed the effects of acute, single-session tVNS on cardiovascular autonomic function compared with the effects of sham (ear lobe/placebo) stimulation among 14 healthy participants 55 years of age and older. They collected baseline values and measured heart rate variability (HVR) and baroreflex sensitivity. 

“Since not all participants responded to tVNS, we examined if it was possible to identify potential tVNS responders from baseline parameters.”

In the second study, the researchers explored the effects of acute, single-session tVNS on autonomic function in the same age group and expanded the sample to 51 participants. The third study examined 26 participants in the same age group when administered tVNS once per day, for 15-minutes, over the course of two weeks. The researchers reported the impacts of daily tVNS in measures of autonomic function, health-related quality of life (QoL), mood, and sleep.

“Transcutaneous vagal nerve stimulation (tVNS) acutely administered to the tragus in healthy volunteers aged ≥ 55 years was associated with improvements in spontaneous cardiac baroreflex sensitivity and HRV.”

CONCLUSION

“For the first time, we have shown that age-related autonomic, QoL, mood and sleep changes may be improved with tVNS administered every day for two weeks.”

Although the researchers note that there are opportunities for improvement in this study design and further research is needed, participants reported improved sleep, depression, tension, vigor, and mood disturbance after two weeks of daily tVNS.

“These findings therefore suggest that daily tVNS may be an effective means of improving aspects of everyday life in this age group.” 

Click here to read the full research paper, published by Aging.

—

Aging is an open-access journal that publishes research papers bi-monthly in all fields of aging research and other topics. These papers are available to read at no cost to readers on Aging-us.com. Open-access journals offer information that has the potential to benefit our communities from the inside out and may be shared with friends, neighbors, colleagues, and other researchers, far and wide.


For media inquiries, please contact media@impactjournals.com.

No comments

TRENDING WITH IMPACT: EFFECTS OF EXERCISE ON AGING

  By

Researchers surveyed available literature related to exercise and its association with longevity and aging. This extensive review expands on exercise as a lifestyle intervention and its ability to counteract cellular and tissue aging.

Figure 4. Conceptual overview. Created in BioRender.

The Trending with Impact series highlights Aging publications that attract higher visibility among readers around the world online, in the news, and on social media—beyond normal readership levels. Look for future science news about the latest trending publications here, and at Aging-US.com.

—

Listen to an audio version of this article

Regular physical exercise provides benefits for both the body and mind, but how exactly does this healthy habit benefit our cells, signaling pathways, organs, and even bones? Furthermore, how can we employ regular exercise as part of an anti-aging strategy to extend our healthspan and lifespan?

Two researchers from the Beta Cell Aging Lab at Harvard Medical School authored a recent review paper which breaks down the currently available research on this very topic, with a special focus on pancreatic beta-cells and Type 2 diabetes. The authors detailed the recorded effects of exercise at systemic and cellular levels, its effects on each of the hallmarks of aging, and a potential molecular regulatory node that may integrate those effects. This review was published in May of 2021 by Aging, and entitled: “Effects of exercise on cellular and tissue aging.”

THE NINE HALLMARKS OF AGING

With age, cellular functions and systems in the human body progressively decline and destabilize, which eventually leads to disease and all-cause mortality. There are nine hallmarks of aging, which are classified as either primary, secondary, or integrative: genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient-sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. 

“Exercise is a promising lifestyle intervention that has shown antiaging effects by extending lifespan and healthspan through decreasing the nine hallmarks of aging and age-associated inflammation.” 

The researchers in this review explain that exercise is capable of counteracting each of these hallmarks of aging at systematic and cellular levels. They used publicly available research to cite and discuss the effects of exercise in each hallmark of aging in clear and thorough detail. The purpose of this article is to summarize this review, though readers are highly encouraged to read the full paper for deeper insights. 

“The literature was surveyed on MEDLINE through freely accessible PubMed as a search engine for the terms: ‘exercise’, ‘longevity’ and ‘aging’; the most relevant studies were included as they related to the 9 hallmarks of aging.”

AMPK AS A CENTRAL REGULATOR

“In summary, exercise attenuates all hallmarks of aging through different molecular pathways and effectors that seem independent and disconnected.” 

Given that exercise regulates each of these hallmarks individually, the researchers hypothesize that there must exist some kind of molecular regulatory node(s) capable of coordinating these responses. They propose that the 5’ adenosine monophosphate-activated protein kinase (AMPK) enzyme/protein could play this role.

“In summary, AMPK activation through exercise can impact all the hallmarks of aging through different signaling pathways as summarized in Figure 2 and can act as a signaling node capable of orchestrating many of the effects of exercise on the health span of different tissues and organs.”

EXERCISE AND TYPE 2 DIABETES

The researchers also discuss the effects of exercise on Type 2 diabetes mellitus (T2D). 

“In summary, exercise activates molecular signals that can bypass defects in insulin signaling in skeletal muscle and increase skeletal muscle mitochondria, which are associated with improved insulin sensitivity in skeletal muscle and therefore improve aging-associated effects of T2D.”

Figure 1. Effects of exercise upon the aging process of different organs and systems. Created in BioRender.
Figure 1. Effects of exercise upon the aging process of different organs and systems. Created in BioRender.

CONCLUSION

“We propose that future studies should address the effects of exercise on tissues which are not considered its direct targets but do show accelerated aging in T2D, such as pancreatic β-cells. In these, the role of AMPK and its physiological control will become especially significant as exercise is considered a cellular antiaging strategy.”

Click here to read the full review, published by Aging.

—

Aging is an open-access journal that publishes research papers monthly in all fields of aging research and other topics. These papers are available to read at no cost to readers on Aging-us.com. Open-access journals offer information that has the potential to benefit our societies from the inside out and may be shared with friends, neighbors, colleagues, and other researchers, far and wide.

For media inquiries, please contact media@impactjournals.com.

No comments

The Epigenetic Clock, Aging, and Rejuvenation

  By

Researchers discuss the role that the epigenetic clock may play in the aging process and in rejuvenation as an approach to set back epigenetic age.

Figure 3. Morphological changes induced by long-term OSKM gene action in human umbilical cord perivascular cells (HUCPVC).
Figure 3. Morphological changes induced by long-term OSKM gene action in human umbilical cord perivascular cells (HUCPVC).

The Top-Performer series highlights papers published by Aging that have generated a high Altmetric attention score. Altmetric scores, located at the top-left of trending Aging papers, provide an at-a-glance indication of the volume and type of online attention the research has received.

Read Aging’s Top 100 Altmetric papers.

—

Listen to an audio version of this article

A centenarian is a human that has lived as long or longer than one hundred years. These individuals are marvels to aging researchers and have been studied at length in hopes of uncovering clues about the mechanisms that drive aging. Many researchers have crafted views and theories about the roots of gerontology; these curiosities have preceded the development of modern science.

In an effort to describe different views and theories of aging—leading to the emergent view of the epigenome as the driver of aging—researchers from the National University of La Plata, National University of Cordoba, World Academy of Art and Science, and Betterhumans Inc., authored a research perspective published by Aging in 2021. This well-written paper describes the role that the epigenetic clock may play in both the aging process and in rejuvenation as an approach to set back epigenetic age. The paper was entitled, “Aging and rejuvenation – a modular epigenome model.”

“The hypothesis proposing the epigenome as the driver of aging was significantly strengthened by the converging discovery that DNA methylation at specific CpG sites could be used as a highly accurate biomarker of age defined by the Horvath clock [5].”

THE EPIGENETIC CLOCK

Throughout our lifetime, the rate of change in DNA methylation at age-dependent CpG sites has been found to consistently correlate with our rate of epigenetic aging and organismal aging. In 2013, researcher Stephen Horvath devised a mathematical algorithm using DNA methylation at specific CpG sites that is a highly accurate biomarker of age. 

“In humans, the epigenetic age calculated by the clock algorithm shows a correlation of 0.96 to chronological age and an error margin of 3.6 years, an unprecedented accuracy for a biomarker of age [5, 24].”

In human babies, from birth to one year old, researchers explain that the ticking rate of the epigenetic clock is very high, as is our rate of aging at this point in the lifecycle. Then, from one to 20 years of age, the rate progressively decelerates. After age 20, the ticking rate is much slower. Among individuals with conditions such as cancer, HIV, obesity, Alzheimer’s disease, and even alcohol abuse, the ticking of the epigenetic clock and aging rate is, unsurprisingly, much higher. In another example, the rate of epigenetic aging is slower in supercentenarians and their children compared with non-centenarians. 

“There is compelling evidence that the ticking rate of the clock is significantly correlated with the rate of biological aging in health and disease.”

THE EPIGENETIC CLOCK & AGE REJUVENATION

Even while they continue to proliferate, embryonic cells (ES) may remain indefinitely young—in a type of “suspended animation.” The epigenetic clock does not tick in embryonic cells, until they differentiate.

“In ES cells, the epigenetic clock does not tick [5] nor does the circadian clock oscillate [26]. Only when ES cells differentiate, both clocks become active and cells begin to age.” 

Over the years, there have been clues indicating that it is possible to rejuvenate non-reproductive (somatic) cells back to induced pluripotent stem (iPS) cells, or embryonic-like cells. When somatic cells are reprogrammed to iPS cells, their epigenetic clocks stop ticking, their circadian clocks cease to oscillate, and ultimately, their epigenetic clock is set back to zero (or close to zero). These clues came from the development of animal cloning in the early 60s and, more recently, cell reprogramming.

The authors of this research perspective explain rejuvenation strategies including cell reprogramming, cyclic partial cell reprogramming, and other non-reprogramming strategies.

Two cell rejuvenation studies were described by the authors of this paper which suggest that, even at advanced stages of age, the epigenome continues to be responsive to command signals, including the OSKM genes, also known as the Yamanaka factors. This finding is compatible with the hypothesis that aging is not associated with DNA damage. The researchers explain two additional possible theories: 1.) Aging is preprogrammed in our DNA and due to progressive epigenome disorganization and loss of epigenetic information. 2.) Aging is not a programmed process, but a continuation of developmental growth driven by genetic pathways, such as mTOR.

“What seems to be clear is that epigenetic rejuvenation by cyclic partial reprogramming or alternative non-reprogramming strategies holds the key to both, understanding the mechanism by which the epigenome drives the aging process and arresting or even reversing organismal aging.”

CONCLUSIONS

In summary, the researchers explain that what the few initial study results seem to suggest is that when the epigenetic clock is forced to tick backwards in vivo, it is only able to drag the phenotype to a partially rejuvenated condition. However, the researchers emphasize that no firm conclusions should be drawn from the very few experimental results currently documented.

“Since we now have molecular tools, like the Yamanaka factors, that allow us to make the clock tick backwards, the time is ripe for opening a new dimension in gerontology, moving from aging research to epigenetic rejuvenation research.”

Click here to read the full research perspective, published by Aging.

—

Aging is an open-access journal that publishes research papers monthly in all fields of aging research and other topics. These papers are available to read at no cost to readers on Aging-us.com. Open-access journals offer information that has the potential to benefit our societies from the inside out and may be shared with friends, neighbors, colleagues, and other researchers, far and wide.

For media inquiries, please contact media@impactjournals.com.

No comments

Trending with Impact: Method Yields Cell-Type-Specific Brain Data

  By

Researchers used a bioinformatics approach (ESHRD) that leverages gene expression data from brain tissue to derive cell-type specific alterations in Alzheimer’s disease.

Neurons cells from the brain under the microscope.
Neurons cells from the brain under the microscope.

The Trending with Impact series highlights Aging publications attracting higher visibility among readers around the world online, in the news, and on social media—beyond normal readership levels. Look for future science news about the latest trending publications here, and at Aging-US.com.

—

Listen to an audio version of this article

Cell-to-cell variability in the human brain is significantly heterogeneous. An abundance of differential brain cell types makes it laborious and expensive for researchers to generate single-cell gene expression data. While some studies use laser capture microdissection (LCM) and single-cell RNA sequencing (scRNA-Seq) to directly address the cellular heterogeneity in brain tissue, due to labor and cost, these studies generally have a small sample size and face power concerns. Most gene expression profiling studies of patients with Alzheimer’s disease (AD) are conducted post-mortem using brain tissue homogenates.

“Ultimately, the overall goal of gene expression profiling in AD is to understand the transcriptome changes in all major cell types of the brain in a well-powered approach that would facilitate the exploration of all the variables mentioned above.”

The need existed for a cost-effective bioinformatics approach to leverage expression profiling data from brain homogenate tissue to derive cell type-specific differential expression and pathway analysis results. In 2020, researchers from Columbia University Medical Center, The University of Sydney School of Medicine, University of Miami, and the Banner Sun Health Research Institute described an Enrichment Score Homogenate RNA Deconvolution (ESHRD) method for identifying alterations in the brain. They published a research paper in Aging’s Volume 12, Issue 5, entitled: “ESHRD: deconvolution of brain homogenate RNA expression data to identify cell-type-specific alterations in Alzheimer’s disease.” 

The Study

“We applied our approach to different gene expression datasets derived from brain homogenate profiling from AD patients and Non-Demented controls (ND) from 7 different brain regions.”

Researchers conducted brain region cell-specific pathway analysis and Gene Set Enrichment Analysis (GSEA). The team mapped and measured five different cell types in seven different brain regions. The cell types included: microglia, neuron, endothelial, astrocyte, and oligodendrocyte. Endothelial and oligodendrocyte are two cell types that are not easily examined in the brain and only very little gene expression data previously existed for Alzheimer’s disease.

“We conducted RNA expression profiling from both brain homogenates and oligodendrocytes obtained by LCM from the same donor brains and then calculated differential expression.”

The researchers used a dataset of Multiple System Atrophy (MSA) patients (n = 4) and controls (n = 5) to validate their ESHRD method. Homogenate, LCM, and scRNA-Seq results were compared using the ESHRD method. They also compared their findings to other research studies.

Results

“The ESHRD approach replicates previously published findings in neurons from AD patient brain specimens, and we extended our work to characterize novel AD-related changes in relatively unexplored cell types in AD, oligodendrocytes and endothelial cells.”

Neuronal, endothelial cells, and microglia were found to be the most represented “cell-specific” gene classes in patient brains with Alzheimer’s disease. Neuronal-specific genes were downregulated and enriched for synaptic processes. Endothelial genes were found to be upregulated in AD and enriched for angiogenesis and vascular functional processes.

“Differentially Expressed Genes (DEGs) we labeled as “mixed” represent the most prevalent class (73.4%), followed by DEGs labeled as microglia (6.6%), neuron (5.9%) and endothelial (5.7%). Astrocyte and oligodendrocyte labeled DEGs have a frequency of 3.6% and 3.1%, respectively.” 

Microglia showed different patterns of expression across the brain in multiple regions. They found that astrocyte genes were enriched in SLC transport and immune processes and oligodendrocytes were enriched for the Glycoprotein metabolism in Alzheimer’s disease.

Conclusion

“We demonstrate the ability of this approach to highlight known neuronal-specific changes in the AD brain and utilize it to identify novel changes in endothelial cells and oligodendrocytes, two cell types not easily examined in the brain and for which only minimal gene expression knowledge exists in AD.”

Click here to read the full study, published by Aging.

—

Aging is an open-access journal that publishes research papers monthly in all fields of aging research and other topics. These papers are available to read at no cost to readers on Aging-us.com. Open-access journals offer information that has the potential to benefit our societies from the inside out and may be shared with friends, neighbors, colleagues, and other researchers, far and wide.

Aging is a proud participant in the AACR Annual Meeting 2021 #AACR21

For media inquiries, please contact media@impactjournals.com.

No comments

Complex Drug Screenings Show Anti-Aging Potential in Natural Compounds

  By

In an effort to mimic metformin and rapamycin, researchers used powerful screening methods to analyze over 800 natural compounds to assess their anti-aging potential and safety profile.

Modern Medical Research Laboratory. Scientific Lab, Drug Engineering Center Full of High-Tech Equipment, Computer Screen Showing DNA concept, Technology for Vaccine Development.

The Top-Performer series highlights papers published by Aging that have generated a high Altmetric attention score. Altmetric scores, located at the top-left of trending Aging papers, provide an at-a-glance indication of the volume and type of online attention the research has received.

Read Aging’s Top 100 Altmetric papers.

—

Listen to an audio version of this article

By 2030, one in five Americans will age over 65 years old in the United States. As a society, an even larger aging population is fast on our heels. With age comes wisdom, and unfortunately, so does a number of costly and devastating diseases, including cancer, cardiovascular disease, Alzheimer’s disease, and Type II diabetes.

Researchers are currently working to mitigate the upcoming burden for this expanding population by developing anti-aging and anti-cancer drugs, and other geroprotective interventions that could extend healthspan, lower disease rates, and maintain productivity. However, the slow and expensive process of gaining approval for new potential pharmaceutical and nutraceutical interventions is historically arduous and prone to failure—especially when it comes to anti-aging and longevity research.

“Even if successful, to be used preventatively, anti-aging drugs face extraordinarily high safety and efficacy standards for approval [9].”

In 2017, researchers from the United States’ Insilico Medicine, Inc. and Life Extension, the United Kingdom’s Biogerontology Research Foundation, Canada’s Queen’s University, and Russia’s Russian Academy of Sciences, worked together to test a strategy to accelerate the development of safe, wide-scale anti-aging nutraceuticals. Their study was published in Aging’s Volume 9, Issue 11, and entitled, “Towards natural mimetics of metformin and rapamycin.” To date, this top-performing research paper has generated an Altmetric Attention score of 127.

Metformin and Rapamycin

“One strategy to hasten the process has been the repurposing of existing, FDA-approved drugs that show off-label anti-cancer and anti-aging potential [10,11], and at the top of that list are metformin and rapamycin, two drugs that mimic caloric restriction [12].”

Metformin and rapamycin have already been FDA approved for use in renal transplants, Type II diabetes, and metabolic syndrome. These two drugs are both mTOR inhibitors which, through numerous research studies, have shown pleiotropic effects exhibiting multiple anti-aging, anticancer, and anti-cardiovascular disease benefits. However, some adverse side effects pertaining to extended use have made it so these two interventions (used alone) are unable to move forward for wide-scale preventative use.

“Taken together, rapamycin and metformin are promising candidates for life and healthspan extension; however, concerns of adverse side effects have hampered their widescale adoption for this purpose.”

Although there are some adverse side effects, the chemical structures of metformin and rapamycin should not be ignored. These two drugs can be analyzed, and even mimicked, to develop new, safer interventions to prevent and treat age-related diseases. The researchers in this study initiated an effort to identify nutraceuticals as safe, natural alternatives to metformin and rapamycin drugs. 

“Nutraceuticals have received considerable attention in recent years for potential roles in preventing or treating a number of age-related diseases [88].”

The Study

“Our work is done entirely in silico and entails the use of metformin and rapamycin transcriptional and signaling pathway activation signatures to screen for matches amongst natural compounds.” 

Test compounds were selected based on the natural compounds listed in the UNPD and Library of Integrated Network‐based Cellular Signatures (LINCS) datasets. Gene‐ and pathway‐level signatures of metformin and rapamycin were mapped and screened for matches against the over 800 natural compounds chosen. The team used conventional statistical methods, pathway scoring-based methods, and training of deep neural networks for signature recognition. Researchers applied several bioinformatic approaches and deep learning methods, including the Oncofinder, Geroscope, and in silico Pathway Activation Network Decomposition Analysis (iPANDA). The iPANDA extracts robust, biologically relevant pathway activation signatures from the data. 

“In an application of these methods, we focused on mimicry of metformin and rapamycin, seeking nutraceuticals that could preserve their anti-aging and disease-preventive potential while being better suited for wide-scale prophylactic use.”

Results and Conclusion

“The analysis revealed many novel candidate metformin and rapamycin mimetics, including allantoin and ginsenoside (metformin), epigallocatechin gallate and isoliquiritigenin (rapamycin), and withaferin A (both). Four relatively unexplored compounds also scored well with rapamycin.”  

Their initial list of over 800 natural compounds was condensed to a shortlist of candidate nutraceuticals that showed similarity to metformin and rapamycin and had low adverse effects. 

“This work revealed promising candidates for future experimental validation while demonstrating the applications of powerful screening methods for this and similar endeavors.”

Click here to read the full research paper, published by Aging.

—

Aging is an open-access journal that publishes research papers monthly in all fields of aging research and other topics. These papers are available to read at no cost to readers on Aging-us.com. Open-access journals offer information that has the potential to benefit our societies from the inside out and may be shared with friends, neighbors, colleagues, and other researchers, far and wide.

Aging is a proud participant in the AACR Annual Meeting 2021 #AACR21

For media inquiries, please contact media@impactjournals.com.

No comments

Rapamycin Rules out DNA Damage Theory of Aging

  By

Dr. Mikhail Blagosklonny gleans an important new discovery in aging research—deduced from recent studies on short-lived mice and rapamycin.

3D illustration of a mutated or damaged DNA strand

The Top-Performer series highlights papers published by Aging that have generated a high Altmetric attention score. Altmetric scores, located at the top-left of trending Aging papers, provide an at-a-glance indication of the volume and type of online attention the research has received.

Read Aging’s Top 100 Altmetric papers.

—

Listen to an audio version of this article

The exact mechanisms at play in the human aging process are still up for debate. A number of great minds in science have proposed plausible aging mechanisms and theories, such as DNA damage, telomere shortening, and DNA damage theories of aging. DNA damage theories suggest that aging is functional decline, caused by the accumulation of molecular damage. However, some scientists counterclaim that neither DNA damage nor telomere shortening limit lifespan or cause aging.

Dr. Mikhail Blagosklonny—an adjunct faculty member at the Roswell Park Comprehensive Cancer Center and Editor-in-Chief at Aging, Oncotarget, Oncoscience, and Cell Cycle—gleaned an important new perspective from recent aging studies, which could have been overlooked. He expanded on this discovery in a recent research perspective that was published in February 2021 in an issue of Aging, entitled: “DNA- and telomere-damage does not limit lifespan: evidence from rapamycin.” To date, this research paper has generated an Altmetric Attention score of 43.

Rapamycin is a macrolide antibiotic that has immunosuppressive properties, regulates a key cellular growth pathway (mTOR), and has been at the center of numerous studies of aging since its discovery in 1964. Dr. Blagosklonny explains that, based on findings from recent mouse-model studies of rapamycin’s effects on short-lived mice, normal aging is not caused by the accumulation of molecular damage or telomere shortening.

“Here I discussed new evidence that normal aging is not caused by accumulation of molecular damage or telomere shortening: while extending normal lifespan in mice, rapamycin failed to do so in mice dying from molecular damage (Figure 1).”

Evidence From Rapamycin

In the study which Dr. Blagosklonny refers to, researchers genetically modified mice to artificially shorten telomeres, administered rapamycin to normal mice and the telomerase-deficient short-lived mice, and observed the effects. In normal mice, results were congruent with a number of other studies that found lifespan was significantly extended. In the telomerase-deficient mice, lifespan was shortened as a result of rapamycin. 

“While shortening lifespan by 18% in unnatural telomerase-deficient mice, in the same study in natural mice, rapamycin increased lifespan by 39% and healthspan by 58% (measured as tumor-free survival) [3].”

Given that rapamycin prolongs life in normal mice, Dr. Blagosklonny asserts that this study proves that normal lifespan is not constrained by telomere length. Telomeres only become life-limiting when they are artificially shortened to the point where rapamycin can no longer extend lifespan. Furthermore, Dr. Blagosklonny explains that although molecular damage and telomere shortening could be life-limiting, they ultimately do not limit life because quasi-programmed aging occurs at a faster rate.

“Although molecular damage accumulates, this accumulation is not life-limiting because quasi-programmed aging terminates life first (Figure 1A). Quasi-programmed (hyperfunctional) aging is life-limiting, because it is favored by natural selection.”

Quasi-Programmed (Hyperfunctional) Aging

In 2012, Dr. Blagosklonny wrote another widely-read research perspective that explains in great detail what his proposed hyperfunction theory of aging is, entitled, “Answering the ultimate question “What is the Proximal Cause of Aging?”

“According to hyperfunction theory, aging is quasi-programmed, a continuation of developmental growth programs, driven in part by hyper-functional signaling pathways including the mTOR pathway [9].”

He explains that hyperfunction is an excessive, yet normal function that occurs later in life. Hyperfunction in this context does not necessarily mean an increase in function and, in some cases, it even means a decrease in function. The same pathways and functions that drive growth and development earlier in life, also drive age-related diseases later in life. Dr. Blagosklonny proposes that quasi-programmed (hyperfunctional) aging is favored by natural selection and is what limits life.

“It is hyperfunctional signaling pathways such as mTOR (one of many) that drive both growth and aging, causing age-related diseases that in turn damage organs, leading to secondary loss of function.”

Many signaling pathways interact with mTOR to drive aging, forming a network, including MEK/MAPK, NF-kB, p63, HIF-1, and many others. Dr. Blagosklonny suggests that, in theory, there could be a number of mTOR-independent factors of quasi-programmed aging that are life-limiting, as well. He goes on to exemplify several lines of evidence concluding that it is not molecular damage that causes normal aging or limits life—it is normal, quasi-programmed (hyperfunctional) aging.

Conclusion

Dr. Blagosklonny mentions a forthcoming review that will be entitled: “When longevity drugs do not increase longevity: Unifying development-driven and damage-induced theories of aging.”

“Once again, damage accumulates and must cause death eventually, but quasi-programmed (hyperfunctional) aging terminates life first. Molecular damage can become life-limiting, when artificially accelerated or, potentially, when quasi-programmed aging is decelerated.” 

Click here to read the full research perspective, published in Aging.

—

Aging is an open-access journal that publishes research papers monthly in all fields of aging research and other topics. These papers are available to read at no cost to readers on Aging-us.com. Open-access journals offer information that has the potential to benefit our societies from the inside out and may be shared with friends, neighbors, colleagues, and other researchers, far and wide.

For media inquiries, please contact media@impactjournals.com.

Aging is a proud participant in the AACR Annual Meeting 2021 #AACR21
Aging is a proud participant in the AACR Annual Meeting 2021 #AACR21
No comments

Risks for Dementia and Mortality: Sleep Disturbance and Deficiency

  By

Researchers used nationally representative data to examine the relationship between sleep disturbance and deficiency and their risk for incident dementia and all-cause mortality among older adults.

Person sleeping in bed and alarm clock in the foreground
Listen to an audio version of this article

Are serious health consequences looming for those with trouble sleeping? Based on a large sum of available research, the answer appears to be yes—poor sleep poses an increased risk of dementia and all-cause mortality. But what defines poor sleep? Conflicting results have been reported by researchers regarding the characteristics of sleep when examining incident dementia and all-cause mortality. For instance, one meta-analysis suggests that sleeping fewer than five hours (short sleep) and longer than nine hours (long sleep) per night is associated with greater risk of mortality. Another meta-analysis finds that only longer than nine hours is associated with greater risk of mortality.

“Research on sleep disturbance and deficiency and all-cause mortality therefore has shown conflicting results. Further, few studies have included a comprehensive set of sleep characteristics in a single examination of incident dementia and all-cause mortality.” 

From Brigham and Women’s Hospital, Harvard Medical School, and Boston College, based out of Massachusetts, United States, a team of researchers saw the need to address the gaps in this research and developed a new study. They organized a single examination of the relationships between a comprehensive set of sleep characteristics and incident dementia and all-cause mortality. This paper was entitled, “Examining sleep deficiency and disturbance and their risk for incident dementia and all-cause mortality in older adults across 5 years in the United States,” and published in Aging’s Volume 13, Issue 3 in February 2021.

The Study

The researchers collected baseline data from the National Health and Aging Trends Study (NHATS). The NHATS is a nationally-representative longitudinal study of Medicare beneficiaries (65 years and older) in the United States. The data were collected from a randomly selected subset of 2,812 participants from the NHATS population that were administered sleep questionnaires in 2013 and 2014.

“Participants with dementia at baseline (year 2013) were excluded (n = 202) for a sample of 2,812 with sleep data in either 2013 or 2014.”

The sleep characteristics measured from the questionnaire were: sleep duration, sleep latency, difficulty maintaining alertness, sleep quality, napping frequency, and snoring. First, participants rated their memory and performed a memory-related activity to assess their cognitive capacity and screen for incident dementia. Body weight was reported by participants annually, and diagnosis of heart attack, heart disease, hypertension, arthritis, diabetes, stroke, and cancer were also self-reported. Annual interviews were conducted to record instances of participant mortality. The researchers used Cox proportional hazards modeling and controlled for confounders to examine each sleep characteristic and outcome.

Results

“Overall, our findings show a strong relationship between several sleep disturbance and deficiency variables and incident dementia over time.”

In the results adjusted for confounders, the team found that longer time to fall asleep and shorter sleep duration predicted incident dementia. They also found that short sleep duration, difficulty maintaining alertness, napping, and poor sleep quality predicted all-cause mortality. Given that short sleep duration was a strong predictor for both incident dementia and all-cause mortality, the researchers suggest that this may be the most important sleep characteristic related to adverse outcomes among older adults. 

“The association observed in our study between short sleep (5 hours or less) and incident dementia screening may be understood via the research drawing upon animal models to demonstrate brain toxin removal during sleep [24].”

Another fascinating finding from this study was the difference between unadjusted and adjusted results for long sleep. As mentioned, previous studies have shown that long sleep is associated with both incident dementia and all-cause mortality. However, after the researchers adjusted for confounders, such as age and chronic conditions, the association between long sleep and incident dementia and all-cause mortality disappeared. The relationship between short sleep and both incident dementia and all-cause mortality remained significant even after full adjustment. These findings stand in contrast to the meta-analyses initially mentioned that have found associations between both short and long sleep and all-cause mortality in adults. The researchers suggest the cause may be that long sleep is a reflection of underlying disease.

“The most parsimonious explanation for the disappearance of the effect of long sleep on dementia and mortality in adjusted models is that the deleterious impact of long sleep is a reflection of underlying disease.”

Conclusion

The researchers confirm that addressing the sleep disturbance and deficiency variables in this study may have a positive impact on risk for incident dementia and all-cause mortality among older adults.

“Also, future research may consider the development of novel behavioral interventions to improve sleep among older adults.”

Click here to read the full study, published on Aging-US.com.

—

Aging is an online open-access journal that publishes research papers monthly in all fields of aging research and other topics. These papers are available to read at no cost to readers on Aging-us.com. Open-access journals offer information that has the potential to benefit our societies from the inside out and may be shared with friends, neighbors, colleagues, and other researchers, far and wide.

For media inquiries, please contact media@impactjournals.com.

No comments

Participating in the 2021 AACR Annual Meeting: Aging (by Impact Journals)

  By

As the world continues to account for COVID-19, this year the American Association for Cancer Research (AACR) Annual Meeting will be a virtual event. Aging, by Impact Journals, is proud to be a participant in the conference on April 10-15 and May 17-21, 2021.

As the world continues to account for COVID-19, this year the American Association for Cancer Research (AACR) Annual Meeting will be a virtual event. Aging, by Impact Journals, is proud to be a participant in the conference on April 10-15 and May 17-21, 2021.
Listen to an audio version of this article

BUFFALO, NY-MARCH 25, 2021 – Aging is indexed by PubMed/Medline abbreviated as “Aging (Albany NY)”, PubMed Central, ISI/Web of Science: Science Citation Index Expanded (abbreviated as Aging‑US and listed in the Cell Biology category; since June 2017 it has also been listed in the Geriatrics & Gerontology category), and Scopus /Rank Q1 (abbreviated as Aging).

Every year, the American Association for Cancer Research (AACR) organizes a conference program that covers the latest discoveries in cancer research. Topics include population science and prevention, cancer biology, translational and clinical studies, survivorship, and advocacy. This conference aims to highlight work from the best minds in research and medicine from institutions all over the world. The journal Aging, by Impact Journals, will be participating at the AACR Annual Meeting this year. 

Impact Journals is an open-access publisher of rigorously peer-reviewed scientific literature, and owns four medical research journals, including Aging. Aging was launched by Impact Journals in 2009 with the goal of spotlighting high-impact papers, authored by scientists who study the process of aging and age-related diseases—including cancer—and now, with a special focus on COVID-19 vulnerability as an age-dependent syndrome. 

Aging has published outstanding papers and reviews by highly-cited authors and award winners, including Andrew V. Schally (Nobel Laureate), Shinya Yamanaka (Nobel Laureate), Lawrence Donehower, Toren Finkel, Stephen Helfand, Gerald Shadel, Andre Nussenzweig, Maurice Burg, Karen Vousden, Leonard Guarente, and Dale Bredesen. Importantly, the Aging Editorial Board also comprises numerous prestigious award winners, including Nobel Laureate Elizabeth H. Blackburn, and many other distinguished scientists, including Cynthia Kenyon, Judith Campisi, Leonard Guarente, Michael Hall, Mikhail Blagosklonny, Vera Gorbunova, David Sinclair, Jan Vijg, and Thomas Rando. 

The journal has recently concluded its 12th year of publishing and has become Impact Journals’ featured journal. Learn more about Aging and Impact Journals at the virtual 2021 AACR conference on April 10-15 and May 17-21, 2021. Registration will be open through the beginning of the event.

About Aging: 

To learn more about Aging, its publication standards, and past or current issues, visit www.aging-us.com.

Follow us on social media @AgingJrnl on Twitter and @AgingUS on Facebook.

About Impact Journals:

Impact Journals is an open-access publisher with four scientific journals: Aging, Oncotarget, Genes & Cancer, and Oncoscience. Our mission to provide scientists with the opportunity to share their exceptional discoveries, offer services that enable rapid dissemination of results, and to present vital findings from the many fields of biomedical science. Our goal is life without disease.

Impact Journals LLC, 6666 E.Quaker St. Ste. 1, Orchard Park, NY 14127

For media requests, please contact media@impactjournals.com.

No comments

Pressurized Oxygen Therapy Can Reverse Mechanisms of Aging

  By

For the first time, researchers demonstrate that hyperbaric oxygen therapy can reverse the mechanisms that mark the aging process.

Oxygen molecules and erythrocytes floating in a vessel in the blood stream.
Oxygen molecules and erythrocytes floating in a vessel in the blood stream.
Listen to an audio version of this article

Aging is the progressive loss of physiological integrity, which results in impaired functionality and increased susceptibility to diseases, and ultimately death. For the first time, researchers collaborated in an in vivo study to observe the effects of hyperbaric oxygen therapy on cellular mechanisms to reverse aging.

Researchers based out of Israel from Shamir Medical Center, Tel-Aviv University, and Bar Ilan University published a groundbreaking new paper titled, “Hyperbaric oxygen therapy increases telomere length and decreases immunosenescence in isolated blood cells : a prospective trial,” in the open access journal, Aging. The importance of this study hinges on understanding the mechanisms of aging that were evaluated by the researchers.

“At the cellular level, two key hallmarks of the aging process include telomere length (TL) shortening and cellular senescence.”

Telomere Length

Telomeres (TLs) function to protect chromosomes from DNA damage and are located at the end of the chromosome. In each instance of cell division, the telomeres shorten due to an inherent inability to fully replicate the DNA strand. Given that cells can only replicate a finite number of times before they can no longer engage in mitosis, the shortening of telomeres has been shown in adults to lead to increased rates of mortality.

Researchers in this study also provide examples of studies that are finding a number of pharmacological agents capable of reducing the shortening rate of telomeres.

“Shortened TLs can be a direct inherited trait, but several environmental factors have also been associated with shortening TL, including stress, lack of physical endurance activity, excess body mass index, smoking, chronic inflammation, vitamins deficiency, and oxidative stress [2, 8, 9].”

Cellular Senescence

The other hallmark mechanism of the aging process is cellular senescence. Previously, senescent cells have been viewed as mechanisms that protect the body against cancer through cell-cycle arrest, however, recent discoveries have found that they also have a role in processes such as development, tissue repair, aging, and age-related disorders. The phase of senescence can be triggered by telomere shortening and other non-telomeric DNA damage.

“The primary purpose of senescence is to prevent propagation of damaged cells by triggering their elimination via the immune system. The accumulation of senescent cells with aging reflects either an increase in the generation of these cells and/or a decrease in their clearance, which in turn aggravates the damage and contributes to aging [1].”

Oxidative Stress

In this well-written paper, the researchers introduce the topic by citing numerous interventional studies measuring the association between telomere length and lifestyle modifications. Studies include the measuring of diet, supplements, physical activity, stress management, and social support. However, the team found that the most common mechanism associated with telomere shortening is oxidative stress.

“Oxidative stress can occur from imbalances between the production of reactive oxygen species (ROS) and cellular scavengers.”

Previous studies indicate that telomeres are highly sensitive to oxidative DNA damage which occurs due to an excess of reactive oxygen species (ROS), or molecular oxygen by-products. The excess formation of these ROS occurs through the sequential reduction of oxygen via the addition of electrons and a lack of scavenger cells to digest excess microorganisms. This leads to the shortening of telomeres.

Hyperbaric Oxygen Therapy

Hyperbaric oxygen therapy (HBOT) has been observed to stimulate brain function and increase cognitive ability in previous studies. HBOT involves patients breathing in 100% oxygen in a pressurized chamber on a repeated basis. Being in this type of environment increases the amount of oxygen that is dissolved in the blood and tissue. Increasing oxygen levels in the body using pure oxygen on a daily basis can induce the hormesis phenomenon. This eustress type of therapy has been shown to have beneficial and positive effects on the body and mind.

“Single exposures [to HBOT] increase ROS generation acutely, triggering the antioxidant response, and with repeated exposures, the response becomes protective [13, 18].”

The Study

This study was designed to evaluate the effects of HBOT on the telomeres and concentrations of senescent cells in aging/healthy adults. Thirty-five participants living independently at 64+ years of age received HBOT exposures daily, over the course of 60 days.

Researchers collected whole blood samples prior to intervention (baseline), at the 30th and 60th session, and 1-2 weeks after the last HBOT session. They assessed the telomere lengths and senescence of peripheral blood mononuclear cells (PBMCs) in each participant’s blood sample.

Figure 3. Senescent cell changes with HBOT.
Figure 3. Senescent cell changes with HBOT.

“In this study, for the first time in humans, it was found that repeated daily HBOT sessions can increase PBMC telomere length by more than 20% in an aging population, with B cells having the most striking change. In addition, HBOT decreased the number of senescent cells by 10-37%, with T helper senescent cells being the most affected.”

Conclusion

Following HBOT, telomere lengths increased by over 20% in T helper, T cytotoxic, natural killer, and B cells. There was also a significant decrease in the number of senescent T cytotoxic and T helper cells observed in the participant blood samples, allowing for new healthy cells to regenerate.

“In conclusion, the study indicates that HBOT may induce significant senolytic effects including significantly increasing telomere length and clearance of senescent cells in the aging populations.”

Click here to read the full scientific paper, published in Aging.

Learn more about Hyperbaric Oxygen Therapy (HBOT)

—

Aging is an open-access journal that publishes research papers monthly in all fields of aging research and other topics. These papers are available to read at no cost to readers on Aging-us.com. Open-access journals offer information that has the potential to benefit our societies from the inside out and may be shared with friends, neighbors, colleagues and other researchers, far and wide.

  • Follow Us