Leptin, Serum

Leptin is an adipocyte-derived hormone that functions as an afferent signal in a negative-feedback loop that maintains constancy of adipose mass and regulates the adaptive neuroendocrine and metabolic response to alterations in nutritional state. Circulating leptin levels are directly related to adipose tissue mass.High leptin levels signal the presence of sufficient energy stores to sites in the central nervous system, which respond by reducing appetite and increasing energy expenditure, thus, preventing severe obesity. Leptin levels change rapidly with feeding or fasting disproportionately to the changes in fat depot. In addition, leptin levels are acutely increased by inflammatory and infectious stimuli indicating that leptin is part of the immune response and host defence mechanisms.

Mutations in the leptin gene, which is associated with profound obesity and over-eating, and leptin deficiency as a result of food restriction, lipodystrophy and congenital absence of adipose tissue are associated with profound metabolic and physiologic abnormalities, including hyperphagia, neuroendocrine dysfunction, and alterations of the immune system. Leptin treatment largely corrects starvation-induced immune dysfunction and partially blunts the neuroendocrine response to Leptin, Serum starvation. However, it does not correct starvation-induced hypoglycaemia, hypoinsulinaemia, hyperphagia, or fully block weight regain if an individual is allowed to feed without control.

2 ml Serum Room Temperature

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