What's Hot
What's Hot
News flashes are posted here frequently to keep you up-to-date with the latest advances in health and longevity. We have an unparalleled track record of breaking stories about life extension advances.
Testosterone replacement boosts cognitive function in men participating in lifestyle intervention
September 29 2021. A secondary analysis of a trial reported on August 10, 2021 in The American Journal of Clinical Nutrition found that testosterone replacement therapy improved cognition among a group of older men with obesity and hypogonadism (low testosterone levels) who participated in an intensive lifestyle intervention.
“To our knowledge, the current study is the first randomized clinical trial to examine whether testosterone replacement therapy may improve cognitive function with lifestyle behaviors controlled via lifestyle intervention therapy in this prevalent but understudied population of older men with coexisting obesity and hypogonadism,” authors Giulia Gregori of the Michael E. DeBakey VA Medical Center in Houston and colleagues announced.
The Lifestyle Intervention and Testosterone Replacement in Obese Seniors (LITROS) trial evaluated the effect of treatment with testosterone combined with a lifestyle intervention on physical performance in obese men aged 65 years and older with low levels of the hormone. The trial included 83 men who participated in a weight management program combined with exercise training who received a topical testosterone gel or a placebo gel for six months. While the primary outcome of the trial was a change in physical performance, and secondary outcomes included measures of frailty, cognition was additionally assessed at the beginning and end of the trial.
The current analysis focused on improvement in cognition. While cognitive test scores improved in both groups compared to the beginning of the study, men who received testosterone had significantly better composite cognition scores and attention/information and memory subscores than those who received a placebo.
“These findings suggest that in the high-risk population of older men with obesity and hypogonadism, testosterone replacement may improve cognitive function with lifestyle behaviors controlled via lifestyle intervention therapy,” the authors concluded.
—D Dye
Fewer errors in protein production increased life span in experimental research
September 27 2021. An article that appeared on September 14, 2021 in Cell Metabolism reported that increasing the fidelity of protein synthesis is associated with longevity in yeast, worms and flies.
“We commonly hear about DNA mutations, which can cause cancer, and are considered one of the underlying causes of aging,” explained senior author Ivana Bjedov. “However, mistakes in proteins which affect organismal health are largely neglected, despite the fact that errors introduced during synthesis of new proteins are much more frequent than mutations made during DNA replication.”
“For this study we therefore focused on protein errors, and we questioned if fewer mistakes in proteins improve health.”
Dr Bjedov and her colleagues genetically engineered metazoan (from the animal kingdom) intracellular components known as ribosomes to carry a mutation from a single-celled organism that survives at high temperatures. (Ribosomes are the cells’ protein-producing factories.) Introduction of the mutation into yeast, worms and fruit flies resulted in improved accuracy in the production of proteins, in addition to longer life. The researchers demonstrated that longevity drugs, including rapamycin, torin and trametinib also decreased protein translation errors. In addition, rapamycin further extended life in animals with the ribosome mutation.
“The process of making proteins is not error free – ribosomes make mistakes,” noted first author Victoria Eugenia Martinez-Miguel. “We have shown, for the first time, that changing a single amino acid in the ribosome decoding center reduces protein synthesis mistakes and improves an organism’s stress resilience and longevity.”
“This is the first study in a metazoan organism to reveal that fewer mistakes in proteins can prolong health and longevity; we expect our results on yeast, worms and flies to be extended to mammals, which could potentially lead to treatments for improved health in the elderly,” coauthor Filipe Cabreiro predicted.
—D Dye
Do people who supplement with vitamin C have greater mental vitality?
September 24 2021. A trial that evaluated the effects of vitamin C supplementation in healthy young adults found increased aspects of mental vitality and improved performance among those who received the vitamin. The research was reported on September 2, 2021 in the European Journal of Nutrition.
Minju Sim of Seoul National University and colleagues team conducted a cross-sectional study that examined the association of serum vitamin C levels with aspects of mood and vitality among 214 young adults. Higher levels of the vitamin were found to be associated with improved attention.
Acting on these results, the researchers conducted a randomized, double-blind trial in which 46 healthy men and women between the ages of 20 and 39 years with inadequate levels of vitamin C received 500 milligrams of the vitamin twice daily or a placebo for four weeks. Fatigue, attention, work engagement, and self-control resources were evaluated as indicators of vitality at the beginning and end of the study. A test that evaluated sustained attention and processing speed after mental stress was administered to both groups at the end of the study.
After four weeks, participants who received vitamin C had greater increases in attention and work absorption scores than the placebo group, with trends toward decreased fatigue and greater comprehensive work engagement. Processing speed was increased in the vitamin C group compared to the placebo group at the end of the study.
“This study is the first, to our knowledge, to show the link between vitamin C status with mental functions in healthy young adults using both population-based observational studies and randomized clinical trials,” the authors announced.
They concluded that “Vitamin C supplementation effectively increased work motivation and attentional focus and contributed to better performance on cognitive tasks requiring sustained attention.”
—D Dye
Time-restricted eating: valuable tool in chronic metabolic disease management
September 22 2021. An article published on September 22, 2021 in Endocrine Reviews explores circadian rhythms in metabolism and discusses the potential role of time-restricted eating, a form of intermittent fasting, in the prevention of chronic metabolic diseases.
“Intermittent fasting can improve sleep and a person’s quality of life as well as reduce the risk of obesity, diabetes and heart disease,” observed senior author Satchidananda Panda, PhD, of the Salk Institute for Biological Studies in La Jolla, California.
Time-restricted eating is a diet management technique in which daily calories are consumed within a period of eight to ten hours or less. “People who are trying to lose weight and live a healthier lifestyle should pay more attention to when they eat as well as what they eat,” Dr Panda suggested. “Time-restricted eating is an easy-to-follow and effective dietary strategy that requires less mental math than counting calories.”
Maintaining a long overnight fast is one way to conceptualize time-restricted eating. Long fasting periods have been associated with lower chronic disease risk. In human pilot studies, time-restricted eating has been associated with lower body weight and reductions in glucose intolerance, hypertension and abnormal lipids.
Recent research suggests that adopting a daily short window of feeding helps sustain a healthy circadian rhythm. The body’s circadian rhythms dictate the activity of genes, hormones and metabolism at different times during a 24 hour day. “Eating at random times breaks the synchrony of our internal program and makes us prone to diseases,” Dr Panda explained.
By aligning when we eat with the body’s internal clock, health is optimized, and chronic disease risk is reduced.
"Intermittent fasting is a lifestyle that anyone can adopt,” Dr Panda stated. “It can help eliminate health disparities and lets everyone live a healthy and fulfilling life."
—D Dye
Protein named for mythical land of perpetual youth rejuvenates cells
September 20 2021. Tír na nÓg is described in Irish folklore as a place of everlasting youth, health and beauty. In the September 3, 2021 issue of Science Advances, researchers from the University at Buffalo and the Roswell Park Cancer Institute revealed that NANOG, a protein named for this mythical land, reverses aging in skeletal muscle cells.
“Senescence of myogenic progenitors impedes skeletal muscle regeneration,” the authors wrote. “Here, we show that overexpression of the transcription factor NANOG in senescent myoblasts [stem cell precursors of muscle cells] can overcome the effects of cellular senescence and confer a youthful phenotype to senescent cells.”
Senescent cells are aged cells that are no longer able to grow and divide but remain in the body to secrete damaging proinflammatory compounds. The team found that overexpression of NANOG in myoblasts lowered signs of cellular senescence, including genome instability and mitochondrial dysfunction. NANOG upregulated DNA repair proteins and reactivated autophagy (a process by which debris within cells is broken down and repurposed) via upregulation of AMP-activated protein kinase (AMPK).
NANOG overexpression was found to increase the number of muscle stem cells in the muscles of prematurely aged mice, suggesting that cellular aging can be reversed without reprogramming cells to an embryonic state.
“Our work focuses on understanding the mechanisms of NANOG’s actions in hopes of discovering druggable targets in signaling or metabolic networks that mimic the anti-aging effects of NANOG,” commented corresponding author Stelios T. Andreadis, PhD, who is a State University of New York Distinguished Professor in the Department of Chemical and Biological Engineering at the University at Buffalo School of Engineering and Applied Sciences. “Ultimately, the work could help lead to new treatments or therapies that help reverse cellular senescence and aid the many people suffering from age-related disorders.”
—D Dye
Melatonin protects kidneys against antibiotic-induced damage
September 17 2021. A study reported on August 17, 2021 in the journal Antimicrobial Agents and Chemotherapy revealed a protective effect for supplementing with the hormone melatonin against injury to the kidneys induced by the antibiotic vancomycin.
“Vancomycin is associated with nephrotoxicity, and the mechanism may in part be related to oxidative stress,” noted authors Luigi Brunetti and colleagues. “In vitro and preclinical studies suggest that melatonin supplementation decreases oxidative stress.”
The retrospective study included 303 hospital patients treated with vancomycin, among whom 101 also received melatonin. Acute kidney injury was defined as an absolute increase in serum creatinine (a marker of kidney function) of at least 0.3 milligrams per deciliter (mg/dL) or 50%.
Supplementing with melatonin was associated with a 63% adjusted decrease in acute kidney injury in vancomycin-treated patients. The researchers believe that melatonin’s ability to decrease oxidative stress, which can induce cell death and increase kidney-damaging toxins, is the mechanism whereby the hormone protects the kidneys.
“We’ve known from previous studies the ability of vancomycin to induce kidney injury through oxidative stress and mitochondrial damage, and we also knew how melatonin could restore renal mitochondrial function, so making these findings in this small group of patients was promising and could lead to bigger therapeutic breakthroughs,” stated Dr Brunetti, who is an associate professor at Rutgers University’s Ernest Mario School of Pharmacy. “We hope our findings pave the way for larger group studies as acute kidney injury affects millions of people.”
The study is the first of its kind to evaluate melatonin and kidney injury in humans. “Although this was a retrospective study with a small sample size, given the magnitude of the difference seen, further large prospective studies are warranted,” the authors recommended.
—D Dye
Zinc supplementation associated with improvements in oxidative stress, homocysteine
September 15 2021. A systematic review and meta-analysis of clinical trials published on September 12, 2021 in the International Journal of Clinical Practice found an association between supplementing with the mineral zinc and lower levels of homocysteine and a biomarker of oxidative stress.
Oxidative stress occurs when oxidants and antioxidants are imbalanced, resulting in an increase in reactive oxygen species (ROS). Greater ROS production overwhelms the body’s capacity to overcome their adverse effects, resulting in an increased risk of chronic disease risk.
Homocysteine is an amino acid that increases oxidative damage in the body when elevated above normal levels. High homocysteine levels have been linked to cardiovascular disease, stroke, Alzheimer disease and other disorders.
For the meta-analysis, Meysam Zarezadeh at Tabriz University of Medical Sciences and colleagues selected 18 articles that included a total of 1,187 participants. Eleven articles reported clinical trials that evaluated the association between zinc supplementation and malondialdehyde (MDA, a biomarker of oxidative stress), three articles evaluated zinc’s association with thiobarbituric acid reactive substances (TBARS, another biomarker of oxidative stress) and four articles studied supplemental zinc’s effect on homocysteine.
Supplementing with zinc was associated with a significant reduction in MDA, which was greater among subgroups who received less than 40 milligrams zinc per day. Zinc supplementation was also associated with a significant decrease in homocysteine, particularly among type 2 diabetics. No significant association was observed between zinc supplementation and TBARS levels.
“This meta-analysis demonstrated that zinc supplementation reduces malondialdehyde and homocysteine levels in adult subjects,” the authors concluded. “Supplementation with elemental zinc less than 40 mg/day has optimum effect on oxidative stress biomarkers. However, future studies are required to assess the effect of zinc on oxidative stress conditions in different demographic subgroups.”
—D Dye
Nicotinamide riboside improves inflammation and other factors in rodent model of Alzheimer disease
September 13 2021. The September 14, 2021 issue of the Proceedings of the National Academy of Sciences reported a study that found improvement in brain inflammation in mice bred to develop Alzheimer disease that received nicotinamide riboside (NR), a precursor of nicotinamide adenine dinucleotide (NAD+).
“Alzheimer disease is a progressive and fatal neurodegenerative disorder,” wrote Yujun Hou of the National Institute on Aging and colleagues. “Impaired neuronal bioenergetics and neuroinflammation are thought to play key roles in the progression of Alzheimer disease, but their interplay is not clear.”
NAD+ is a metabolite that exists in all human cells and is necessary for the production of adenosine triphosphate (ATP), which the body uses for energy. NAD+ is important for DNA repair and mitophagy (the degradation of defective mitochondria), which are impaired in brain cells affected by Alzheimer disease.
Dr Hou and associates observed an increase in markers of inflammation and a reduction in NAD+ in mice bred to accumulate brain amyloid characteristic of Alzheimer disease compared to normal animals. By treating these mice with NR for five months, brain NAD+ levels improved and proinflammatory cytokines, DNA damage and cellular senescence were reduced. Nicotinamide riboside was also shown to improve learning and memory.
The researchers speculated that NR may affect the cGAS–STING pathway, which is activated by DNA damage and neuroinflammation. Further research indicated that NR may downregulate neuroinflammation by reducing the activation of this pathway.
“NAD+ precursors, such as NR, are dietary supplements and generally considered safe and have already been tested on healthy individuals, even at high doses, with no toxic side effects observed,” the authors wrote. “The study presented here provides insights into the interconnected network between nicotinamide riboside, senescence, and neuroinflammation in Alzheimer disease and suggests potential targets for future interventional studies.”
—D Dye
Greater vitamin D intake associated with increased brain cortical thickness among older individuals
September 10 2021. The September 2021 issue of The Journal of Nutrition reported a study conducted by researchers at Rush University that revealed an increase in thickness of the cortex (outer layer) of the brain’s temporal lobe and regions that are vulnerable to Alzheimer’s disease among men and women with a high intake of vitamin D.
The current study included 263 cognitively unimpaired participants in the ongoing Mediterranean-DASH Intervention for Neurodegenerative Delay trial. Participants were at least 65 years of age or older. Questionnaire responses provided data concerning vitamin D intake from food and supplements.
Magnetic resonance imaging (MRI) of the brain revealed an association between total vitamin D intake and increased cortical thickness of the temporal lobe as well as in a composite measurement of areas potentially affected by Alzheimer disease. Compared to those whose vitamin D intake was among the lowest 25% of participants at less than 207 IU per day, participants whose intake was among the top 25% at 1,194 IU or more per day had an adjusted 0.038 millimeters (mm) thicker temporal lobe and a 0.043 mm increase in Alzheimer-vulnerable regions.
Among participants who reported supplementing with 800 to 1,000 IU per day vitamin D, temporal lobe measurements were an adjusted 0.039 mm thicker and Alzheimer’s regions were 0.037 mm greater in comparison with no supplementation. For participants whose supplemental vitamin D intake was 1,000 IU per day or higher, the respective increases were 0.047 mm and 0.046 mm. Vitamin D from food alone was not associated with brain cortical thickness.
“In cognitively unimpaired overweight older adults, we found an association between higher total and supplemental vitamin D intakes and greater cortical thickness in regions vulnerable to Alzheimer disease,” the authors concluded. “The results of our study should be confirmed in prospective cohort studies or clinical trials investigating the impact of vitamin D supplementation on brain outcomes.”
—D Dye
Nutritional supplementation during adolescence associated with lower risk of adult-onset MS
September 8 2021. A population-based case-control study published in the November 1, 2021 issue of Multiple Sclerosis and Related Disorders revealed a protective effect for a nutritious diet and supplementation with specific nutrients during adolescence against the development of primary progressive multiple sclerosis (PPMS) in adulthood.
Primary progressive multiple sclerosis is a type of MS that progresses gradually from the initial appearance of symptoms without relapse or remission. An estimated 10 to 15% of patients with MS have PPMS.
“To the best of our knowledge, so far, no study has specifically investigated the effect of nutritional factors during adolescence on PPMS onset,” Nasim Rezaeimanesh and colleagues at Iran’s University of Medical Sciences announced.
The team compared 143 men and women diagnosed with PPMS to 400 sex-matched control subjects within the same community who did not have the disease. Questionnaire responses provided information concerning demographics and dietary and supplement intake between the ages of 13 and 19 years.
A significantly lower risk of PPMS was observed in association with greater adolescent intake of vegetables, fruit, nuts, dairy products, seafood and red meat. “The need of protein varies according to the degree of physical maturation,” Dr Rezaeimanesh and associates remarked. “Inadequate protein intake and iron deficiency anemia during adolescence could result in immune response impairment and infection susceptibility.”
Among fish oil users, the adjusted risk of developing PPMS was 52% lower than the risk experienced by those who did not consume fish oil. Multivitamin, calcium, iron, folic acid, vitamin B12 and vitamin C supplementation were associated with adjusted risk reductions of 33%, 84%, 17%, 38%, 88% and 92%.
“Our data proposed that adequate intake of food groups and nutrient supplementation during adolescence may be effective in reducing adult-onset PPMS risk,” the authors concluded.
—D Dye
Senolytics may combat disc degeneration
September 3 2021. Research reported in Nature Communications on September 3, 2021 suggests a role for senolytic compounds to protect against spinal disc degeneration, a common cause of chronic back pain.
Senolytics help remove aged, senescent cells that secrete damaging enzymes and inflammatory proteins which negatively impact surrounding healthy cells. Removal of these senescent cells may improve tissue function.
A team at Thomas Jefferson University administered the drug dasatinib and the plant compound quercetin (both of which have senolytic actions) to young, middle-aged and older mice once per week until the animals attained old age. Compared to a placebo, the combination was found to reduce senescent cells and disc degeneration in young and middle-aged mice.
Contrary to the researchers’ expectations, the treatment was less effective in older mice than among younger mice, among whom it also protected against further decline. “We anticipated that in tissues with a lot of senescence, removing the senescent cells would make a big difference, but it didn’t,” commented lead researcher Makarand Risbud, PhD, who is the division director of orthopedic research and codirector of the cell biology and regenerative medicine graduate program at Thomas Jefferson University. “The therapy was most effective when we started treating the mice when those senescent cells were just beginning to emerge. Our findings show that if given early, senolytic drugs can actually slow disc degeneration. This is a novel preventive approach.”
“It is possible that people will have to take this for a long time for treatment to be effective, and our data show that the drugs were well-tolerated, at least in mice,” he added. “Once intervertebral discs start to degenerate, there is very little regeneration that happens. But our results show that it is possible to mitigate the disc degeneration that happens with aging.”
—D Dye
Moderate coffee drinking associated with lower risk of mortality during 11-year median follow-up
September 1 2021. Research presented at ESC (European Society of Cardiology) Congress 2021 revealed a lower risk of dying from any cause during an 11-year median period among light to moderate coffee drinkers in comparison with men and women who had no intake.
The study included 468,629 UK Biobank participants of an average age of 56.2 years who had no indications of heart disease upon enrollment. Coffee intake was classified as none, light to moderate at 0.5 to 3 cups per day or high at over 3 cups per day. A subgroup of participants underwent magnetic resonance imaging (MRI) of the heart to assess cardiac structure and function.
Light to moderate coffee intake during the follow-up period was associated with a 12% decrease in the risk of dying from any cause, a 17% lower risk of cardiovascular mortality and a 21% reduction in the incidence of stroke in comparison with the risks associated with not drinking coffee.
“The imaging analysis indicated that, compared with participants who did not drink coffee regularly, daily consumers had healthier sized and better functioning hearts,” reported study author Judit Simon, of Semmelweis University in Budapest. “This was consistent with reversing the detrimental effects of aging on the heart.”
“To our knowledge, this is the largest study to systematically assess the cardiovascular effects of regular coffee consumption in a population without diagnosed heart disease,” she announced. “Our results suggest that regular coffee consumption is safe, as even high daily intake was not associated with adverse cardiovascular outcomes and all-cause mortality after a follow-up of 10 to 15 years. Moreover, 0.5 to 3 cups of coffee per day was independently associated with lower risks of stroke, death from cardiovascular disease, and death from any cause.”
—D Dye
