Mid-life obesity may be triggered by enzyme, not poor lifestyle choices and lack of will power, study on mice shows
Findings of US National Institutes of Health study could overturn current notions about why people gain weight as they age
US researchers have identified an enzyme that may play a central role in the development of obesity in mid life.
In two groups of mice being fed high-fat foods, those who received an inhibitor that blocked the enzyme had a 40 per cent decrease in weight gain compared with those that did not receive the drug. The findings, published in the US journal Cell Metabolism, could upend current notions about why people gain weight as they age, and could one day lead to more effective weight-loss medications.
“Our society attributes the weight gain and lack of exercise at mid life (approximately 30 to 60 years) primarily to poor lifestyle choices and lack of will power, but this study shows that there is a genetic programme driven by an overactive enzyme that promotes weight gain and loss of exercise capacity at mid life,” said lead study author Jay Chung, head of the Laboratory of Obesity and Aging Research at the National Heart, Lung, and Blood Institute (NHLBI), part of the US National Institutes of Health.
Researchers have known for years that losing weight and maintaining the capacity to exercise tend to get harder beginning between ages 30 to 40 – the start of mid life. Scientists have developed new therapies for obesity, including fat-fighting pills, but many of those therapies have failed.
Chung and his associates searched for biochemical changes that occurred in middle-aged animals that are equivalent to 45 years in humans. They found that an enzyme called DNA-dependent protein kinase, or DNA-PK, increases in activity with age. In the meantime, the researchers said, middle-aged people who are fighting obesity should not abandon common practices of reducing calorie intake and boosting exercise, even if it takes a while to see results. Xinhua
Fit fathers produce mentally healthier male children, study finds
Fit fathers could be boosting the mental health of their unborn children, according to Australian research. The study, published by the Florey Institute of Neuroscience and Mental Health, found that physically active male mice had male offspring that were better at coping with fear. Furthermore, male mice which were stressed before conception were more likely to produce anxious and depressed children.
In the study, male mice were put through a four-week “boot camp”, then mated with inactive females. Brains of the offspring were compared with those who had inactive mothers and fathers. “Our most striking findings were that the male offspring of running mice were better at suppressing bad memories as juveniles, and had lower anxiety levels as adults than male offspring of sedentary fathers,” says lead researcher Anthony Hannan. “In contrast, female offspring of fit fathers showed no differences to the female offspring of sedentary fathers.”
The study has indicated to researchers that the lifestyle and environment of a child’s father is more influential than previously thought. Hannan said the team would now focus on studying epigenetics, how genes interact with the environment to better understand the phenomenon.
“It’s not just about the child’s genes or the woman’s health that’s important to their offspring, it’s potentially also the man’s health before conception as the information in the sperm may reflect the lifestyle of the father,” says Hannan. “This has huge public health implications. We seem to have epidemics of chronic high levels of stress in society, sedentary behaviours, lack of exercise and poor diets.”
Exposure to the aroma of rosemary essential oil can help memory in children
Children who are exposed to the aroma of rosemary essential oil have better working memory, according to a study at the British Psychological Society Annual Conference in Brighton. Dr Mark Moss says: “Our previous study demonstrated the aroma of rosemary essential oil could enhance cognition in healthy adults. Knowing how important working memory is in academic achievement we wanted to see if similar effects could be found in children in classroom settings.”
A total of 40 children aged 10 and 11 took part in a class-based test. Children were randomly assigned to a room that had either rosemary oil diffused in it for 10 minutes or a room with no scent. The children were tested individually, seated at the table opposite the researcher. After introducing herself to the child the researcher said: “You are here to play some memory games. Please don’t be nervous but try the best you can to remember what I ask you to.” Analysis revealed that the children in the aroma room received significantly higher scores than the non-scented room. The test to recall words demonstrated the greatest different in scores.
“Why and how rosemary has this effect is still up for debate.” says Moss. “It could be that aromas affect electrical activity in the brain or that pharmacologically active compounds can be absorbed when adults are exposed. “We do know that poor working memory is related to poor academic performance and these findings offers a possible cost effective and simple intervention to improve academic performance in children. The time is ripe for large-scale trials of aroma application in education settings.”
