Metformin modulates PI3K and GLUT4 expression and Akt/PKB phosphorylation in human endometrial stromal cells after stimulation with androgen and insulin.
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.


METHODS
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.


CONCLUSIONS
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.
Laboratório de Biologia Molecular Endócrina e Tumoral, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Brazil; Laboratório de Ginecologia e Obstetrícia Molecular, Centro de Pesquisa Experimental, Departamento de Ginecologia e Obstetrícia, Hospital de Clínicas de Porto Alegre, UFRGS, Brazil.
Gustavo Dias
GD
Ferreira
Department of Gynecological Endocrinology and Reproductive Medicine, University Hospital Heidelberg, Heidelberg, Germany.
Ariane
A
Germeyer
Laboratório de Biologia Molecular Endócrina e Tumoral, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Brazil; Laboratório de Ginecologia e Obstetrícia Molecular, Centro de Pesquisa Experimental, Departamento de Ginecologia e Obstetrícia, Hospital de Clínicas de Porto Alegre, UFRGS, Brazil.
Amanda
A
de Barros Machado
Laboratório de Biologia Molecular Endócrina e Tumoral, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Brazil; Laboratório de Ginecologia e Obstetrícia Molecular, Centro de Pesquisa Experimental, Departamento de Ginecologia e Obstetrícia, Hospital de Clínicas de Porto Alegre, UFRGS, Brazil.
Tadeu Ludwig
TL
do Nascimento
Department of Gynecological Endocrinology and Reproductive Medicine, University Hospital Heidelberg, Heidelberg, Germany.
Thomas
T
Strowitzki
Laboratório de Biologia Molecular Endócrina e Tumoral, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Brazil; Laboratório de Ginecologia e Obstetrícia Molecular, Centro de Pesquisa Experimental, Departamento de Ginecologia e Obstetrícia, Hospital de Clínicas de Porto Alegre, UFRGS, Brazil.
Ilma Simoni
IS
Brum
Laboratório de Biologia Molecular Endócrina e Tumoral, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Brazil; Laboratório de Ginecologia e Obstetrícia Molecular, Centro de Pesquisa Experimental, Departamento de Ginecologia e Obstetrícia, Hospital de Clínicas de Porto Alegre, UFRGS, Brazil; Serviço de Ginecologia e Obstetrícia, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, Porto Alegre, RS CEP 90035-003, Brazil.
Helena
H
von Eye Corleta
Laboratório de Biologia Molecular Endócrina e Tumoral, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Brazil; Laboratório de Ginecologia e Obstetrícia Molecular, Centro de Pesquisa Experimental, Departamento de Ginecologia e Obstetrícia, Hospital de Clínicas de Porto Alegre, UFRGS, Brazil; Department of Gynecological Endocrinology and Reproductive Medicine, University Hospital Heidelberg, Heidelberg, Germany; Serviço de Ginecologia e Obstetrícia, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, Porto Alegre, RS CEP 90035-003, Brazil. Electronic address: edcapp@ufrgs.br.
Edison
E
Capp
D000328:Adult; D000728:Androgens; D002478:Cells, Cultured; D004717:Endometrium / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D005260:Female; D051275:Glucose Transporter Type 4 / Q000378:metabolism*; D006801:Humans; D017588:Hyperandrogenism / Q000378:metabolism; D006946:Hyperinsulinism / Q000378:metabolism; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin; D008687:Metformin / Q000494:pharmacology*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D011085:Polycystic Ovary Syndrome / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D017154:Stromal Cells
D000728:Androgens; D051275:Glucose Transporter Type 4; D007004:Hypoglycemic Agents; D007328:Insulin; C495692:SLC2A4 protein, human; D008687:Metformin; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases
Akt; Endometrial stromal cells; GLUT4; Insulin; Metformin; PI3K