The Leptin Receptor
Overall, leptin signals the brain to tell you not to eat as much and tells your body to burn more calories. Once leptin binds the leptin receptor, it causes an increase in production of PMOC. If your brain cannot respond to this signal, then it keeps you hungry and your body burning fewer calories. This happens when the LepR gene is defective. A mutation in this receptor gene causes similar effects as in the leptin gene mutations. Babies have a normal birth weight, develop rapid weight gain in the first few months of life, and weigh more than 33 lbs by 1 year old. By adolescence, they have 65% body fat. They have an intense desire to eat. These people can exhibit aggressive behavior when they cannot get food. Only 11 cases have been reported, showing that this a rare genetic disorder. There is excessive fat over the trunk and limbs. Low thyroid hormone levels and small gonads (testicles and ovaries) are associated with this gene defect. In turn, normal puberty does not occur. They also have high levels of insulin.
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It is important you
discuss any weight loss or exercise plan with your doctor. Only you and
your physician can decide what is best for you. Some people have
certain conditions that prevent them from doing all exercises, and goal
body weights may be different for different people. You need to discuss
all these things with your physician before starting any weight loss or
exercise program. This article was written by John Vickery, MD. References Fauci et al., Harrison's Principles of Internal Medicine 17th ed., ch 74 Endocrine Reviews 27(7):710-718 Endocrinol Metab Clin N Am 2008;37:733-751 Ann Intern Med. 2010;152:93-100
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