Rosiglitazone Promote Apoptosis In Human Uterine Leiomyoma Cells Through The PI3K/Akt Pathway

[OBJECTIVE]To explore the effect of peroxisome proliferator activated receptor-γ (PPARγ)activator rosiglitazone on cells proliferation and apoptosis and the expressions ofestrogen receptor, Bad and p21gene in human uterine leiomyoma cells, to furtherinvestigate the action of phosphatidylinositol-3kinase/serine/threonine kinase((PI3K/Akt) signal pathway in these course and to provide the experimental evidencefor the clinical application of PPARγ agonist in the patients with the uterineleiomyoma.[METHODS]The human uterine leiomyoma cells were obtained by the primary culture. Thehuman uterine leiomyoma cells were identified by immunocytochemical method andusing the monoclonal antibody of β-actin. Primary culture human leimyoma cellswere treated with different concentrations of rosiglitazone (10-8mol/L,10-7mol/L and10-6mol/L) for24,48and72hours，and MTT assay was used to detect the growthcurve. The rates of apoptosis of human leimyoma cells were measured by flowcytometry. The level of estradiol in culture medium was measured by radio-immunityassay. The mRNA and protein expressions of estrogen receptor α and β in humanleimyoma cells were measured by Real-time PCR and Western-Blot. The proteinexpressions of Akt, p-Akt, Bad and p21gene. The estrogen receptor agonistraloxifene and PI3K/Akt signal pathway specific agonist insulin-like growth factor(IGF-1) were used in our study.[RESULTS](1) Compared with the control group, the proliferations of human uterineleiomyoma cells were significantly inhibited by treatment with10-8mol/L,10-7mol/L and10-6mol/L rosiglitazone for48and72hours in a dose-dependent andtime-dependent manner. The proliferations of human uterine leiomyoma cells intreatment with10-8mol/L,10-7mol/L and10-6mol/L rosiglitazone for24hours haveno significant difference. The rates of apoptosis of human uterine leiomyoma cellswere also markedly increased by treatment with10-8mol/L,10-7mol/L and10-6mol/Lrosiglitazone for72hours in a dose-dependent manner.(2) Compared with the control group, the levels of estradiol in culture mediumwere decreased in a dose-dependent manner by treatment with10-8mol/L,10-7mol/Land10-6mol/L rosiglitazone for72hours. The expressions mRNA and protein ofestrogen receptor α and β in human leimyoma cells were decreased in adose-dependent manner by treatment with10-8mol/L,10-7mol/L and10-6mol/Lrosiglitazone for72hours in a dose-dependent manner. The effects of rosiglitazone onthe proliferations and apoptosis of the human leimyoma cells were partly abolished bythe estrogen receptor agonist raloxifene.(3) Compared with the control group, the protein expression of phosphorylationAkt (p-Akt) was significantly down-regulated by treatment with10-6mol/Lrosiglitazone for72hours. But rosiglitazone did not affect the protein expression oftotal Akt. The effects of rosiglitazone on the proliferations, apoptosis and the proteinexpression of p-Akt in the human leimyoma cells were abolished by PI3K/Akt signalpathway specific agonist IGF-1.(4) Compared with the control group, the protein expression of Bad and p21genewere up-regulated by treatment with10-6mol/L rosiglitazone for72hours.[CONCLUSIONS]Peroxisome proliferator activated receptor-γ rosiglitazone inhibits the cellsproliferation and promotes the cells apoptosis in human uterine leiomyoma cells,which the mechanisms may be relate to the decrease of estradiol secretion and thedecrease of estrogen receptor α and β expressions and the up-regulation of Bad andp21induced by rosiglitazone through PI3K/Akt signal pathway.