Free Essays, Term Papers, Research Papers at Anti Essays

InObesity, Brain Becomes ‘Unaware’ of Fat – Medical News Daily

More than 60% of Americans are overweight, and it seems that obesity has become the tragedy of our generation. This article documents a study published in the Cell Metabolism journal, which suggests that obesity maybe “hard-wired” in the brain at birth. The study is based on the notion that since most individuals’ average weight is relatively constant despite changes in food intake, so there has to be some sort of neural and hormonal imbalance of energy expenditure in obese people. This study points at defects in the neurons of the arcuate nucleus (ARH), that leave the affected individual less-responsive to the hunger suppressing hormone, leptin. When leptin was first discovered, scientists thought that they had found the key to obesity, but soon thereafter, it was realized that it is not the hormone itself, but it is rather the lack of response to leptin that causes obesity. In fact, overweight individuals have high circulating levels of leptin, as they have developed a form of resistance against it. Therefore, the focus of this study was on the key players in the leptin signaling cascade, to determine where the imbalance occurs in obese individuals compared to normal. In the experiment performed, obese animals maintained the right amount of leptin receptors, but their SOCS-3 levels rose markedly. SOCS-3 (Suppressors Of Cytokine Signaling) protein, is a negative regulator of leptin, as when leptin levels increase, SOCS-3 works to decrease its levels. According to this study, SOCS-3 seems to override the leptin signal completely in obesity, decreasing the response, if any, to circulating leptin levels. However, the downstream elements in the leptin signaling cascade remain ready and functional. These findings probably have great implications for the development of anti-obesity drugs.
This study clearly suggests a link between obesity and genes, and validates the...