Older men have an increased risk of fathering children who eventually develop bipolar disorder, according to new research. It’s the latest study to refute the earlier theory that men could father children into their old age with no ill effects; other recent studies have linked older fathers to an increased risk of miscarriages, and to children with schizophrenia or autism.
The theory linking paternal age with an offspring’s health rests on the genetics of aging sperm. Spontaneous mutations can accumulate in the genes of a man’s sperm cells as he ages. These cells divide as many as 660 times by the time a man reaches 40, by some estimates. Each division increases the risk of acquiring a harmful mutation from erroneous gene copying, the theory holds [Science News]. Women are born with their full complement of eggs already in place in the ovaries, and therefore don’t have to worry about increased genetic errors as they age.
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The trick to keeping organs working well into old age might be taking out the trash, according to a study in Nature Medicine [subscription required]. Researchers led by Ana Maria Cuervo of Yeshiva University in New York have slowed the aging process in the livers of mice by tinkering with a system that recycles the damaged proteins hanging around in a cell.
Molecules responsible for “chaperone-mediated autophagy“ handle about 30 percent of the cells’ damaged proteins, escorting them to inner cell structures called lysosomes, where enzymes break the proteins down. Studies by Cuervo have shown that the disposal system becomes less efficient as cells grow older. They’ve also pinpointed the reason for the age-related decline — a loss of receptors on the surface of the lysosomes that causes a buildup of damaged proteins in the cell [U.S. News & World Report].
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A genetic study of worms has challenged the prevailing theory of aging, which holds that organisms eventually break down and die as a result of wear-and tear on their bodies. Researchers have found that certain genes in the worms are genetically programmed to stop functioning as the worm ages; while there’s no guarantee that a similar process takes place in humans, the results nevertheless give hope that science eventually may find a way to stop or reverse the aging process [HealthDay News].
Researchers have thought that aging is due to damage inflicted on our cellular DNA (genetic material) by factors such as smoking, disease, the sun’s ultraviolet rays and chemically reactive molecules called free radicals, which are produced when our cells make energy. [This study] suggests instead that a combination of factors is at play—that in addition to [environmental factors], there are also certain genes that may carry instructions to start the aging process [Scientific American].
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A hormone therapy sometimes called “medical castration” that’s used to treat prostate cancer is of no help to patients in the early stages of the disease, according to a new study. What’s more, the treatment’s side effects far outweigh any potential benefit for most patients [Los Angeles Times].
The treatment, which cuts off the production of male hormones, has been found to be effective in treating aggressive prostate cancer that is spreading through the body; this prompted doctors to begin prescribing the hormone therapy to patients with early stage, localized tumors as well. But the results of this new study are likely to reverse that trend. Hormone therapy’s most obvious side effect is sexual dysfunction. Of greater concern are several recent studies linking [these] therapies to diabetes, heart disease, bone fractures, and reduced muscle mass [WebMD].
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The “good” cholesterol that is found in olive oil and avocados has been portrayed as a good fairy lately based on its association with healthy hearts, but a new study may give people another reason to chow down on guacamole. A broad study of people in their 50s and 60s revealed that low levels of good cholesterol are linked to poor memory, which may be an early indicator of dementia and Alzheimer’s.
The results, reported in a journal [subscription required] published by the American Heart Association, showed that 60-year-olds with low levels of good cholesterol were 53 percent more likely to have memory problems. However, other researchers point out that the study did not prove causation, and said the study did not yet support larger diet trials aiming to boost levels [BBC News].
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The onset of dementia in an aging relative can be a devastating thing to watch, as memory and cognition slowly degrade. But a new study suggests one easy thing you can do to help hold back the fog: Turn on bright lights, and keep them on all day.
The study in the Journal of the American Medical Association [subscription required] suggests that this simple intervention may boost a patients’ cognition by reinforcing the body’s circadian clock, the sleep-wake cycle that can be modulated by daylight. When the circadian rhythms are disrupted (as in a case of jet-lag), the brain releases hormones and other agents that can affect cognition.
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This is the kind of medical news that always leads to people feeling happy and virtuous as they rush to the nearest liquor store. A new study has just revealed that resveratrol, a compound found in red wine, slowed down the genetic aging of middle-aged lab mice, and appeared to keep their hearts particularly young and healthy.
Of course, resveratrol is also found in grapes, pomegranates, and other foods, and medical researchers still don’t know whether the amount found in a glass of red wine has a clear effect on humans. But the report in the journal Public Library of Science ONE brings enough interesting and promising data to the table to warrant the popping of a few corks.
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