Intrauterine Growth Restriction Programs the Hypothalamus of Adult Male Rats: Integrated Analysis of Proteomic and Metabolomic Data.

Programming of hypothalamic functions regulating energy homeostasis may play a role in intrauterine growth restriction (IUGR)-induced adulthood obesity. The present study investigated the effects of IUGR on the hypothalamus proteome and metabolome of adult rats submitted to 50% protein-energy restriction throughout pregnancy. Proteomic and metabolomic analyzes were performed by data independent acquisition mass spectrometry and multiple reaction monitoring, respectively. At age 4 months, the restricted rats showed elevated adiposity, increased leptin and signs of insulin resistance. 1356 proteins were identified and 348 quantified while 127 metabolites were quantified. The restricted hypothalamus showed down-regulation of 36 proteins and 5 metabolites and up-regulation of 21 proteins and 9 metabolites. Integrated pathway analysis of the proteomics and metabolomics data indicated impairment of hypothalamic glucose metabolism, increased flux through the hexosamine pathway, deregulation of TCA cycle and the respiratory chain, and alterations in glutathione metabolism. The data suggest IUGR modulation of energy metabolism and redox homeostasis in the hypothalamus of male adult rats. The present results indicated deleterious consequences of IUGR on hypothalamic pathways involved in pivotal physiological functions. These results provide guidance for future mechanistic studies assessing the role of intrauterine malnutrition in the development of metabolic diseases later in life.

L-arginine abolishes the hypothalamic serotonergic activation induced by central interleukin-1ß administration to normal rats.

IL-1ß-induced anorexia may depend on interactions of the cytokine with neuropeptides and neurotransmitters of the central nervous system control of energy balance and serotonin is likely to be one catabolic mediator targeted by IL-1ß. In the complex interplay involved in feeding modulation, nitric oxide has been ascribed a stimulatory action, which could be of significance in counteracting IL-1ß effects.The present study aims to explore the participation of the nitric oxide and the serotonin systems on the central mechanisms induced by IL-1ß and the relevance of their putative interactions to IL-1ß hypophagia in normal rats.Serotonin levels were determined in microdialysates of the ventromedial hypothalamus after a single intracerebroventricular injection of 10 ng of IL-1ß , with or without the pre-injection of 20 µg of the nitric oxide precursor L-arginine. IL-1ß significantly stimulated hypothalamic serotonin extracellular levels, with a peak variation of 130 ± 37% above baseline. IL- 1ß also reduced the 4-h and the 24-h food intakes (by 23% and 58%, respectively). The IL-1ß-induced serotonergic activation was abolished by the pre-injection of L-arginine while the hypophagic effect was unaffected.The data showed that one central effect of IL-1ß is serotonergic stimulation in the ventromedial hypothalamus, an action inhibited by nitric oxide activity. It is suggested that, although serotonin participates in IL-1ß anorexia, other mechanisms recruited by IL-1ß in normal rats are able to override the absence of the serotonergic hypophagic influence.