Atividade funcional de fagócitos do leite de mães hiperglicêmicas leve e diabéticas e sua regulação neuroimunoendocrinológica: interações com lgA e melatonina
Year: 2012
Type: dissertation
Abstract: Melatonin is involved in a number of physiological and oxidative processes, including functional regulation in human milk. The present study investigated the mechanisms of action of melatonin and its effects on the functional activity of colostral phagocytes in diabetic women. Colostrum samples were collected from normoglycemic (N=38) and diabetic (N=38) women. We determined superoxide release, bactericidal activity and intracellular Ca release by colostral phagocytes treated or not with 8-(Diethylamino) octyl-3,4,5-trimethoxybenzoate hydrochloride (TMB-8) and incubated with melatonin and its precursor (N-acetyl-serotoninNAS), antagonist (luzindole) and agonist (chloromelatonin-CMLT). Melatonin stimulated superoxide release by colostralphagocytes from normoglycemic but not hyperglycemic women. NAS increased superoxide, irrespective of glycemic status, whereas CMTL increased superoxide only in cells from the normoglycemic group. Phagocytic activity in colostrum increased significantly in the presence of melatonin, NAS and CMLT, irrespective of glycemic status. The bactericidal activity of colostral phagocytes against enterophatogenic Escherichia coli (EPEC) increased in the presence of melatonin or NAS in the normoglycemic group, but not in the hyperglycemic group. Luzindole blocked melatonin action on colostrum phagocytes. Phagocytes from the normoglycemic group treated with melatonin exhibited an increase in intracellular Ca release. Phagocytes treated with TMB-8 (intracellular Ca inhibitor) decreased superoxide, bactericidal activity and intracellular Ca release in both groups. The results suggest that melatonin action is associated to glucose metabolism control in colostral phagocytes. In mononuclear cells of normoglycemic women, melatonin probably increases the ability of colostrum to protect against EPEC, whereas in cells of diabetic mothers it likely mediates anti-inflammatory processes.
Source: Americanae (AECID Library)
Author: Glilciane Morceli
Language: Portuguese
Topic: Infant Nutrition and Health
Subfield: Nutrition and Dietetics
Field: Nursing
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W819487463