Of Exercise, Mice, and Men?
Would you exercise if it meant you’d have smarter babies? In a new study that was published in Cell Reports, exercising male mice produced offspring with enhanced brain activity. Physical exercise has been shown to alter gene expression- turning certain genes on and others off, and now it looks like these changes can be passed along to the next generation- a phenomenon known as epigenetics. There has been plenty of research showing how exercise has a positive effect on our brains, from improving mood, increasing neuronal connections, enhancing brain activity, as well as improving memory. But for the first time, albeit in male mice, we can observe an epigenetic effect of exercise and brain activity. Furthermore, the mice had not been active until they were adults, and still passed along the beneficial changes in their brain activity to their pups. The exercising and non-exercising male mice were paired with sedentary female mice. Only the offspring from the male mice who exercised showed the same enhanced neuronal connections that result from exercising as their fathers. They also learned faster and remembered better than the mice whose parents were sedentary, even though none of the pups ran. For this study, the scientists also focused on two particular microRNAs, molecules that are known to have an effect on genes. Levels of these two microRNAs increase in the brains of mice after they start exercising, and are believed to enhance the connection between brain cells. For the first time, they also found increased levels in the sperm of the running mice. But the increase in microRNAs in the active adult mice were not found in their sedentary pup. What this research tells us is that exercise can have a positive impact on brain activity in both adult mice, as well as their sedentary offspring. But the epigenetic effect stops at the second generation. None of the sedentary second generation mice produced pups with the same enhanced brain activity that they had inherited from their parents. In order to pass along the benefits of increased neuronal connections for generations to come, it is essential for each generation to exercise. The bottom line: Start moving, and keep moving at any age, to have smart babies… and encourage them to exercise too! by Rima Sidhu, MS Exercise Physiology Maze Sexual and Reproductive Health