Participation of ghrelin in the neonatal exposure to lipopolysaccharide and thermoregulation during endotoxemia in adulthood

• Grant number: 13/07417-4
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): August 01, 2013
• Effective date (End): December 31, 2014
• Field of knowledge: Biological Sciences - Physiology - General Physiology
• Principal researcher: Evelin Capellari Cárnio
• Grantee: Mayara Andrade Ferrari
• Home Institution: Escola de Enfermagem de Ribeirão Preto (EERP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The coexistence of two criteria of SIRS in the presence of the infectious confirms the diagnosis of sepsis. It is reported that septic shock induces high mortality rates, around 50%, being the most common cause of admission to intensive care units noncoronary. Any microorganism can cause sepsis or septic shock, but bacteria are the most common etiological agents and Gram-negative bacteria are the main bacteria that lead to sepsis. The lipopolysaccharide (LPS), a component of the outer wall of gram-negative bacteria, activates an intense inflammatory cascade, where there is release of cytokines. Prior exposure to infection, especially during the neonatal period, contributes to individual differences in susceptibility to disease during adulthood. Animals neonates undergoing LPS administration, react differently in the face of a new LPS administration in adulthood. LPS-induced fever during shock endotoxêmico is attenuated when animals are pre-exposed to endotoxin in the neonatal period. One factor that could lead to attenuation in response to LPS would be decreased synthesis of pro-inflammatory cytokines, due to an increase in plasma glucocorticoids. Ghrelin, a peptide hormone originally found in the stomach, has also effects on the modulation of the inflammatory response. Are found for the ghrelin specific receptors on neutrophils, lymphocytes and macrophages and their activation by ghrelin inhibits the production of several inflammatory cytokines. It is observed that administration of ghrelin reduces serum levels of cytokines induced by LPS, as well as nitric oxide production and attenuation of fever induced by LPS. Therefore, our goal will be to evaluate the involvement of ghrelin in the attenuation of fever during endotoxemia in adulthood induced by neonatal exposure to LPS. (AU)