RESUMO
OBJECTIVE: To assess the effect of metformin on gene and protein expression of insulin receptor (IR) and IGF-1 (IGF-1R) receptor in human endometrial stromal cells after stimulation with androgen and insulin. STUDY DESIGN: Primary culture of endometrial stromal cells stimulated with estrogen, progesterone with or without androgen or insulin, and treated with metformin for 24 and 48 h, followed by RNA (qRT-PCR) and protein (Western blot) extraction and analysis. RESULTS: IR gene expression was increased after treatment with insulin (2.9-fold change, p = 0.027) and further after metformin treatment (4.7-fold change, p < 0.001), and in IGF-1R, the group treated with insulin (1.83-fold change) and metformin (1.78-fold change) showed more expression, than control group (p < 0.001). Similarly, IR protein expression was increased after addition of metformin and insulin (249,869 ± 15,878) in relation to the other groups (p < 0.001). Furthermore, cells treated with insulin (153,634 ± 29,123) and androgen plus insulin (162,854 ± 86,258) had a higher IR protein expression compared to control (104,654 ± 5,634) and androgen group (71,595 ± 3,439, (p = 0.045 and 0.021). In groups treated with insulin (127,711 ± 4,591) and androgen plus insulin (151,098 ± 5,194) the protein IGF-1R was increased compared to control (79,355 ± 3,470) and the androgen-only group (79,326 ± 3,114) (p < 0.001). CONCLUSION: Metformin in combination with insulin increased IR protein and gene expressions, while it had no influence on the protein expression of IGF-1R in endometrial stromal cells.
Assuntos
Endométrio/citologia , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Metformina/farmacologia , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/metabolismo , Androgênios/farmacologia , Western Blotting , Células Cultivadas , Endométrio/efeitos dos fármacos , Estrogênios/farmacologia , Feminino , Expressão Gênica , Humanos , Reação em Cadeia da Polimerase/métodos , Progesterona/farmacologia , Receptor IGF Tipo 1/genética , Receptor de Insulina/genética , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismoRESUMO
OBJECTIVE: To assess the effect of metformin on expression of Akt, ERK, PI3K and GLUT4, proteins associated with the growth factor signaling cascade, in human endometrial stromal cells after stimulation with androgen and insulin. STUDY DESIGN: Primary culture of endometrial stromal cells were stimulated in different groups with estrogen, progesterone, androgen and insulin and treated with metformin for 10min, 24h and 48h. After 14 days, proteins were extracted for Western blot analysis. RESULTS: PI3K and GLUT4 expression were increased in the insulin-treated group and further attenuated when metformin was added. The ERK protein was not affected, whereas the Akt phosphorylation was significantly decreased by the action of metformin. CONCLUSION: Metformin affects human endometrial stromal cells by acting on proteins related to growth factors, usually increasing their expression when combined with insulin. Akt phosphorylation was inhibited by metformin, possibly due to its anti-proliferative action.
