Maternal Melatonin Therapy Attenuated Maternal High-Fructose Combined with Post-Weaning High-Salt Diets-Induced Hypertension in Adult Male Rat Offspring

Consumption of food high in fructose and salt is associated with the epidemic of hypertension. Hypertension can originate from early life. Melatonin, a pleiotropic hormone, regulates blood pressure. We examined whether maternal melatonin therapy can prevent maternal high-fructose combined with post-weaning high-salt diet-induced programmed hypertension in adult offspring. Pregnant Sprague-Dawley rats received either a normal diet (ND) or a 60% fructose diet (HF) during pregnancy and the lactation period. Male offspring were on either the ND or a high-salt diet (HS, 1% NaCl) from weaning to 12 weeks of age and were assigned to five groups (n = 8/group): ND/ND, HF/ND, ND/HS, HF/HS, and HF/HS+melatonin. Melatonin (0.01% in drinking water) was administered during pregnancy and lactation. We observed that maternal HF combined with post-weaning HS diets induced hypertension in male adult offspring, which was attenuated by maternal melatonin therapy. The beneficial effects of maternal melatonin therapy on HF/HS-induced hypertension related to regulating several nutrient-sensing signals, including Sirt1, Sirt4, Prkaa2, Prkab2, Pparg, and Ppargc1a. Additionally, melatonin increased protein levels of mammalian targets of rapamycin (mTOR), decreased plasma asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine levels, and increased the l-arginine-to-ADMA ratio. The reprogramming effects by which maternal melatonin therapy protects against hypertension of developmental origin awaits further elucidation.