EFFECTS OF CHRONIC PRENATAL STRESS ON ADULT BODY WEIGHT, PERCENT BODY FAT WEIGHT AND PLASMA LEPTIN IN MALE RATS

Abstract

Chronic stress experienced by the mother during pregnancy increases potential disease states in the offspring, such as type-2 diabetes and obesity (Mueller, 2006) possibly due to ‘programming’ of the fetus. Rat pups conceived, gestated and born during exposure to chronic stress induced by continuous 20 rpm centrifugation were characterized by low birth weight, adult overweight, and increased adult body fat. Young adult male and female rats were adapted to centrifugation for one week prior to mating. Centrifugation was discontinued at parturition. Centrifuged (CF) and non-centrifuged (nCF) control neonates were fostered to non-manipulated, newly parturient dams. As compared nCF male pups, birth weights of CF male pups were significantly lower (Mean s.e.: nCF, 7.49±0.22gm, CF, 6.30±0.11gm; p<0.01). Body weights remained significantly (p<0.05) lower until Postnatal day (P)12. At P90, body weights of CF males were significantly greater those of nCF males (Mean s.e.: nCF, 487±7 gm; CF, 519±11 gm; p<0.02). Using the Total Body Electrical Conductivity (TOBEC) to determine live body composition, total body fat weight was significantly higher in CF than nCF males (Mean % s.e.: nCF, 44±0.32; CF, 45±0.47; p<0.03). In addition, the appetite hormone, leptin, was significantly (p<0.05) elevated in CF relative to nCF males. Our data suggest that chronic prenatal stress alters the intrauterine milieu, thereby programming adult overweight with correlated changes in body fat and leptin. (NIH Grant HD50201; NASA Grant NNA04CK83).