RESUMO
BACKGROUND: Polycystic Ovary Syndrome (PCOS) is an endocrine-metabolic disorder commonly associated with insulin resistance (IR). Previous studies indicate about the expression of molecules involved in the insulin pathway in endometria of women with PCOS-IR. Therefore, the aim of the present study was to evaluate the effect of insulin and testosterone in the expression of these proteins in the endometria and immortal endometrial stromal cell line (T-HESCs). METHODS: We examined the protein levels of Munc18c, PKC zeta, phospho-PKC Zeta, and Syntaxin-4. Protein levels were assessed by Western Blot and/or immunohistochemistry in proliferative endometria (NPE = 6) and in PCOS endometria with insulin resistance (PCOSE-IR = 6). We also evaluated whether high concentrations of insulin (100 nM) and/or testosterone (100 nM), during a 24 h stimulatory period, affected the expression of these proteins in an immortal endometrial stromal cell line (T-HESCs). Once stimulated, proteins were extracted from cells and were assessed by Western Blot analysis. Immunocytochemistry was performed to detect AR in T-HESC cells. RESULTS: Western Blot data showed decreased expression (p < 0,05) of Munc18c and phospho-PKC Zeta in PCOS-IR endometria (PCOSE-IR) with respect to the control (NPE). In the in vitro study, Western Blot analysis showed decreased levels of Munc18c, PKC Zeta and phospho-PKC Zeta with the different hormonal treatments when compared to the control condition (no hormonal stimulation) (p < 0,05). The AR was present in the endometrial stromal cell line (T-HESC). CONCLUSION: The conditions of hyperinsulinism and hyperandrogenism present in PCOS-IR patients modulate the expression and/or phosphorylation of the proteins involved in the insulin pathway at the endometrial level. These data extend to the T-HESCs cells results, where insulin and testosterone exert an effect on both the expression and phosphorylation of proteins present in the pathway.
Assuntos
Endométrio/metabolismo , Insulina/metabolismo , Proteínas Munc18/biossíntese , Síndrome do Ovário Policístico/metabolismo , Proteína Quinase C/biossíntese , Proteínas Qa-SNARE/biossíntese , Adulto , Linhagem Celular , Feminino , Humanos , Receptores Androgênicos/biossínteseRESUMO
Mast cells (MCs) play a crucial role in inflammatory reactions. Their presence and number in the peritoneal cavity is important to overcome and enhance resistance to peritoneal infection. When MCs are activated they release a variety of biological mediators from their granules, such as histamine, that contribute to the appropriate and rapid local immune response. Granular content is released using a process of compound exocytosis, also termed degranulation. SNAP-23 and syntaxin 4 are plasma membrane proteins involved in degranulation of rat MCs. Their presence, however, has not been studied in MCs of other rodent species. The aim of the present study was to investigate using immunocytochemistry whether SNAP-23 and syntaxin 4 are present in peritoneal MCs of the mouse and hamster. In addition, the diameter, percentage and histamine content of these cells were also analyzed. Our results demonstrate that SNAP-23 and syntaxin 4 are present in the mouse and hamster peritoneal MCs, suggesting that proteins involved in the secretory process in MCs are conserved among species. Likewise, we conclude that peritoneal MCs of mouse and hamster are heterogeneous in size, percentage and histamine content.