my personal edition > obesity > news


  E-Mail this DGReview to a colleague

DGReview

Factors Influencing Leptin Receptor Expression

Gender, adiposity, hormones, and recombinant leptin regulate expression of soluble leptin receptors (sOB-R).

Investigators suggest that this observation might inform studies of diseases linked to abnormal leptin levels, such as obesity and anorexia nervosa.

The researchers, from Harvard Medical School, Boston, as well as centres in Athens, Greece, Los Angeles and Leipzig, Germany, enrolled 118 subjects to study factors that determine soluble leptin receptor (sOB-R) levels. In turn, sOB-R expression influences free leptin levels, which are biologically active.

In this cross-sectional study, leptin levels, gender and adiposity determined sOB-R expression. Further multivariate analysis suggested that levels of estradiol (E2) and testosterone predicted sOB-R expression. Insulin levels predicted leptin concentrations and the free leptin index.

In six further patients, sOB-R levels showed a circadian variation that was inverse to that seen with leptin. Therefore, the authors suggested that the diurnal variation in leptin's biological activity might be more pronounced than researchers originally believed.

In eight men, leptin levels declined by 80 per cent following 72-hour fasts. Meanwhile, expression of leptin receptor mRNA by lymphocytes and serum sOB-R levels rose by 100 percent. Administering pharmacological and physiological doses of recombinant-methionyl human leptin to fasted men prevented the increase in sOB-R levels induced by fasting. Pharmacological doses reduced sOB-R levels.
Diabetes 2002;51:2105-2112. "Regulation of Circulating Soluble Leptin Receptor Levels By Gender, Adiposity, Sex Steroids, and Leptin: Observational and Interventional Studies in Humans"

E-Mail this DGReview to a colleague

To print, use this version