Perigestational suppression of weight gain with central leptin gene therapy results in lower weight F1 generation

The efficacy of central leptin therapy on weight homeostasis through various phases of reproduction, pregnancy outcome and postnatal, prepubertal and pubertal growth of offspring was assessed. Enhanced leptin transgene expression after a single intracerebroventricular injection of recombinant adeno-associated virus vector encoding the leptin gene (rAAV-lep) decreased calorie intake and weight in adult nulliparous female rats. rAAV-lep treated rats conceived normally, displayed unremarkable pregnancy rate, parturition and delivered normal sized litters. Significantly lower weight was maintained through gestation, lactation, and post-lactation periods. The maintenance of a modest weight reduction was accompanied by voluntarily reduced calorie intake, increased thermogenic energy expenditure, decreased adiposity as reflected by drastically reduced leptin levels, and suppressed insulin and insulin-like growth factor 1 levels through lactation and post-lactation in rAAV-lep treated dams. The offspring at birth weighed significantly less than those of controls and this lower weight range was sustained during postnatal, prepubertal, pubertal and adult (3 months old) periods, contemporaneous with metabolic circulating hormones in the normal range. For the first time we show the persistent efficacy of central leptin gene therapy to suppress weight gain through all phases of reproduction, lactation and post-lactation in dams and reveal the potential imprinting link to producing lower weight in the F1 generation.