It is a known fact that a healthy diet mixed with regular programs of physical exercises is the key to a slender figure. Until recently, it was believed that obesity is mainly caused by inactivity. However, a new study involving obese mice can turn this theory around. The results of the study speak volumes of a particular side effect of overweight issues that was overlooked before.
The Journal of Cell Metabolism published a paper with a recent study on obese mice. The findings shed light on why people that are struggling with overweight issues are having a harder time adapting to physical exercise training than others. It seems that the excess body weight has no influence over their decision making. What prevents them from terminating their period of inactivity is their altered dopamine receptors.
The study required a number of mice to receive a high fat or a standard diet for a duration of 18 weeks. Right from the second week, the mice from the high-calorie segment developed a heavier body weight. By the start of the fourth week, the same mice stopped from moving as much as before. Instead, they preferred even to make slower moves. Scientists noticed that the inactivity tendency developed in mice before they gained their maximum overweight mass. As a consequence, their overweight issues were not the agents that persuaded them to become less active.
To solve the mystery as to why mice became prone to inactivity, researchers recorded the performance of six distinct components in their dopamine receptors. What they found was that the obese mice developed deficits particularly in the dopamine receptor D2. This is a type of protein that regulates the strength of the cells related to memory capacities. The author of the study believes that this deficit is the most plausible explanation at this hour for the unusual inactivity recorded among people with overweight issues.
The team of scientists proceeded to focus more on the causality between obesity and weight gain. Thus, they altered the dopamine receptors in slender mice so that they develop the same deficit in the D2 receptor. They found that these engineered mice did not gain extra weight more rapidly even though they were put on a high-calorie diet. The explanation for this is that mice continued their same high physical activity. This study aims for dispelling preconceptions about overweight people. Scientists prepare upcoming tests to discover more facts about dopamine.
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