Chimpanzees found to age in ways similar to humans

MARCH 31, 2020 REPORT

by Bob Yirka , Phys.org

A team of researchers from the University of New Mexico and the Kibale Chimpanzee Project in Uganda has found similarities between the way chimpanzees and humans age. In their paper published in Proceedings of the National Academy of Sciences, the group describes their 20-year study of chimps living at Kibale National Park and what they learned about the ways they age.

Prior research has shown that as people age, they undergo changes to their hypothalamic-pituitary-adrenal (HPA) axis—a biological system that plays a major role in how people respond to stress. One of those ways is bumping up levels of cortisol production. Cortisol is a hormone that plays a role in regulating metabolism and blood pressure. Prior research has also shown that excess cortisol can lead to problems such as a reduction in clear thinking, a weakened immune system and inflammation—all symptoms of aging in humans. But now, it appears that chimpanzees undergo a similar process.

The work by the team was part of a large overall effort to study physical and behavioral traits of chimpanzees in a near-natural setting. As part of that effort, team members placed plastic bags in the trees where the chimps reside in the park to collect urine samples from 59 adults. The team has been collecting urine samples from the chimps for approximately 20 years. In analyzing its composition, the researchers have found that the chimps also experience elevated levels of cortisol as they grow older—and furthermore, the higher levels of the hormone could not be attributed to reproductive activity or social status. They claim the increased levels of cortisol suggest chimps age similarly to humans.

The researchers found that cortisol levels were highest in the males when they were making moves on sexually receptive females. They also found that cortisol levels were highest in the females when they were sexually receptive—a time when females are under stress from competing males. They also suggest that rising cortisol levels in hominids are an ancient attribute, and are thus not a byproduct of aging.

Source

Wild insects 'get old' before they die

January 14, 2019, University of Exeter

Short-lived wild insects "get old—losing some of their physical abilities—before they die, new research shows.

Few studies have examined whether insects such as field crickets—whose adult life lasts a few weeks—experience "ageing" in the sense of physical decline in nature.

Insects are used to study ageing in laboratories, but it wasn't clear whether they only reach "old age" because they are protected from a harsh natural environment.

"Just like humans, crickets get old," said lead author Dr. Rolando Rodríguez-Muñoz, of the Centre for Ecology and Conservation on the University of Exeter's Penryn Campus in Cornwall.

"Though we didn't find evidence of 'live fast, die young' in this species, those that put more energy into reproduction early in life showed some signs of faster decline as they aged."

University of Exeter researchers used a network of more than 130 video cameras to study every hour of the lives of a population of wild crickets in a Spanish meadow.

They monitored reproductive effort, ageing and survival over a ten-year period.

They found no evidence of a "trade-off" between reproductive effort in early life (measured by emergence date, calling, searching and winning fights) and survival.

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Functioning of aged brains and muscles in mice made younger: More progress with GDF 11, anti-aging protein

Date:

May 4, 2014

Source:

Harvard University

Summary:

Scientists have shown that a protein they previously demonstrated can make the failing hearts in aging mice appear more like those of young health mice, similarly improves brain and skeletal muscle function in aging mice. In two separate articles scientists report that injections of a protein known as GDF11, which is found in humans as well as mice, improved the exercise capability of mice equivalent in age to that of about a 70-year-old human.

Continued

Surprising Diversity in Aging Revealed in Nature

Dec. 8, 2013 — In our youth we are strong and healthy and then we weaken and die -- that's probably how most would describe what aging is all about. But, in nature, the phenomenon of aging shows an unexpected diversity of patterns and is altogether rather strange, conclude researchers from The University of Southern Denmark.

Not all species weaken and become more likely to die as they age. Some species get stronger and less likely to die with age, while others are not affected by age at all. Increasing weakness with age is not a law of nature.

Read on

Do lazy mammals live longer?

Small furry mammals partial to a daily dose of hibernation in winter are probably extending their lifespan at the same time, according to a study published Wednesday.

Experiments with Djugarian hamsters native to Siberia showed that when the tiny rodents temporarily lower their metabolism and body temperatures, a state called torpor, it stops and even reverses a natural breakdown of chromosomes linked to ageing.

Previous studies had hinted at a causal link between hibernation and longevity, but this is the first one to show the biological mechanism that may account for it.

In the laboratory, researchers led by Christopher Turbill of the Institute for Wildlife Ecology in Vienna created an artificial environment for 25 adult virgin female hamsters, offering only eight hours of light per day.

The faux-winter conditions were designed to trigger a hibernation response, according to the study, published Wednesday by the British Royal Society in the journal Biology Letters.

For 180 days, half the rodents basked in a relatively balmy 20 degrees Celsius (68 degrees Fahrenheit), while the others half lived in a chillier clime, about 9.0 C (48 F). Both groups enjoyed all-you-can-eat buffet.

In measuring the results, the researchers distinguished between shallow torpor, when body temperature dipped below 29 C (84 F), and deep torpor, when temperature dropped under 25 C (77 C), nearly 10 C (18 F) below normal.

They inserted micro-transponders under the animals' skin to keep track of the changes.

Turbill and colleagues suspected that the energy-saving, coma-like state had an impact on telomeres, which sit like tiny caps on the ends of chromosomes, protecting the precious strands of genetic code.

Telomeres and telomerase, the enzyme that control them, are a key agent in ageing and longevity.

Every time a cell divides, the telomeres get worn down a little bit. The enzyme's job is to partially rebuild them. Eventually, when the telomeres are worn beyond repair, cell death is triggered.

Australian-American cell biologist Elizabeth Blackburn, who shared the 2009 Nobel Prize in Medicine for her work in the field, likened telomeres to the "tips of shoelaces" - lose the little plastic end, and the lace starts to fray.

For the hamsters, daily torpor, which typically lasted several hours, somehow acted to preserve these protective tips and even to restore them, the study found.

"This effect was stronger in hamsters using deep torpor, which was primarily in the cold," Turbill said in an email exchange.

Interestingly, these same hamsters also expended more energy, reflected in their higher food intake.

The findings, he added, "are probably applicable to all animals that use some form or torpor or hibernation."

That, alas, does not include humans.

"Torpor and sleep are completely different - and possibly incompatible - states," Turbill said. Humans do not significantly lower their body temperature when sleeping, nor is there a comparable slowdown in metabolic rate.

"So far, science has not come close to finding a way for humans to enter some form of hibernation."

http://www.independent.co.uk/life-style/health-and-families/do-lazy-mammals-live-longer-2355971.html