Menopause for middle-aged men
Estrogen causes middle-aged men to experience changes in body composition and sexual function in a way similar to how women go through menopause, according to a new study.
The new study, published in The New England Journal of Medicine, built upon evidence that a relatively small proportion of testosterone in men is converted into estrogen and that men with more testosterone end up with more testosterone converted into estrogen.
Scientists have conducted previous studies on low testosterone levels in men can cause adverse physical symptoms. Researchers of this study, from Massachusetts General Hospital (MGH), aimed to determine what levels of testosterone and estrogen corresponded with what physical changes.
Participants included 150 men ages 20 to 50, who were divided into two groups. The first group was given daily doses of testosterone (or a placebo) for four months. The second group was given the same testosterone doses but was also given a substance that prevents testosterone from being converted into estrogen.
Findings showed that in the men whose estrogen production was not blocked, varying levels of testosterone respectively corresponded with decreased sexual desire, erectile dysfunction and reduced lean body mass, muscle size and strength.
Men whose estrogen production was blocked showed increased fat and adverse changes in sexual function regardless of testosterone dosage levels.
Results suggest that the decline in estrogen levels can be the exclusive cause of some symptoms, such as weight gain or erectile dysfunction, and that these symptoms aren’t caused by testosterone deficiency alone.
Findings provide insight into the relationship between specific testosterone levels and the decline of physiological functions, which can help researchers determine which men should be treated with testosterone supplements. More significantly, researchers said this study shows that the forms of testosterone used for therapy should be capable of being converted into estrogen.
However, further studies should be conducted to find out how testosterone replacement therapy could affect prostate cancer and prostate enlargement that causes unpleasant symptoms in many older men, researchers said.
Cilantro used to purify water
Developing countries often can’t afford to use in-home water purification systems or more advanced technology to purify drinking water. There is a need for lower-cost, sustainable alternatives, and researchers are conducting studies on various natural materials that can latch on to heavy metals in a way that can filter water.
Mexico, in particular, does not have a system to filter out heavy metals. Professor Douglas Schauer, Ph.D., from Ivy Tech Community College in Indiana, along with six of his students, traveled to Mexico’s Universidad Politécnica de Francisco I. Madero in Hidalgo. Their purpose was to study the effectiveness of an ingredient growing right in their backyards—cilantro.
Schauer and his students worked with scientists from Mexico’s university in small-scale experiments. They found that cilantro may be more effective than some other methods, such as activated carbon, in removing heavy metals from water.
Cilantro’s potential purification abilities could be attributed to the architectural structure of its cells, which lends itself to absorb heavy metals, researchers said. Schauer said their studies suggest that cilantro shows promise as a way to remove toxic heavy metals from water and that it could be used like tea-bags or reusable water filter cartridges to purify drinking water.
Much more research, however, needs to be done to confirm the herb’s purification abilities.
These findings were presented in the 246th National Meeting and Exposition of the American Chemical Society.
Diabetes drug shows promise for treating Alzheimer’s
A new study has led to a drug entering the clinical trial phase as potential treatment to treat symptoms of late-stage Alzheimer’s disease. The drug, liraglutide, is commonly prescribed for people with diabetes to stimulate insulin production.
The new study, published in the journal Neuropharmacology, found that the drug shows promise for treating Alzheimer patients, including the ability to reverse memory loss, prevent toxic plaque build-up on the brain and protect brain cells.
In the study, researchers from Lancaster University in the U.K. tested liraglutide on 14 month-old mice with late-stage Alzheimer’s over a two-month period. They found that the mice, after being injected with the drug, significantly improved upon object recognition tests, and the build-up of toxic plaque in their brains decreased by about 30 percent.
Researchers explained that liraglutide works to reduce oxidative stress, improve growth and replacement of neurons and help the brain cope with stress and toxic influences that contribute to Alzheimer’s.
The drug is now undergoing its first clinical trial in patients with Alzheimer’s, led by Dr. Paul Edison of Imperial College London. The trial will test how Alzheimer’s patients progress when compared to a control group that receives a placebo. Researchers said they hope the trial will give them the first impression of how effective liraglutide is in humans, as opposed to mice.
If the drug works in humans the same way it works in mouse models of Alzheimer’s, this will be the first treatment for human patients that protects “neuronal function and activity, memory and synaptic numbers, while reducing amyloid plaques and the inflammation response in the brain,” researchers said, in which case the use of liraglutide to treat Alzheimer’s would be a landmark discovery.
“Lefties” and “righties” explained by genes
Whether you’re left- or right-handed could be partially caused by genetics, according to researchers from the U.K.
Humans are the only species that shows a strong preference for what hand they use-- approximately 90 percent of the population is right-handed. And the new study, published in the journal PLOS ONE, found correlations between what hand people prefer to use and the presence of certain genes within developing embryos.
Through a study of more than 700 people with dyslexia, scientists determined that one gene in particular was strongly associated with establishing left-right differences in the brain and believe it could influence handedness. The results were then replicated in a study of 2,600 people without dyslexia.
The findings added to evidence from previous studies that this particular gene (PCSK6) is associated with left-right differences in the bodies of mice.
The study’s results suggest that whether an individual prefers to use his or her right or left hand could be a trait caused, at least in part, by genes linked to left-right body differences and the molecular mechanisms that occur early in development, researchers said.
William Brandler, of the MRC Functional Genomics Unit at Oxford University and lead author of the study, said these results do not completely explain the variation of left- and right-handedness among humans. Rather, genetics are one of the several factors that can contribute to the development of handedness, in addition to environment, upbringing and cultural pressures.