Effect Of 17β-estradiol On MRNA Expression Of Leptin And Adiponectin Shown By Human Omental Preadipocytes

Objective:To investigate the effect of 17β-estradiol (1-100nmol/L) on leptin and adiponectin gene expressions in adipocytes.Methods:1.Omental adipose tissue biopsies were obtained from patients undergoing elective open-abdominal surgery.Preadipocytes was separated from omental adipose tissue by dissection and then digested with collagenase typeⅠ.Preadipocytes were incubated in DMEM/F12(1:1) medium at 37℃and then differentiated in vitro into mature adipocytes.2.These cells were incubated for 24 hours in the presence of 1nmol/L,10nmol/L or 100nmol/L 17β-estradiol.Adipocytes were stimulated by 100nmol/L 17β-estradiol for 12 hours,24 hours or 48 hours.We observed the cell morphology and stained it with oil red O for the purpose of adipocyte identification.The levels of leptin and adiponectin mRNA were measured by semi-quantitative RT-PCR.3.Statistical analysis was undertaken using a one-way ANOVA for comparison of control versus treatments.The threshold for significance was P<0.05.Data in the text and figures are expressed as means±SE.Results:1.Human preadipocytes were primary cultured successfully.The fusiform cells were highly homogeneous,proliferative and had a high differentiation rate.Their dynamic morphological changes and extracting stained intracytoplasmic lipid with oil red O all verified their preadipocyte identity.2.Leptin and adiponectin mRNA levels were determined by reverse transcription- polymerase chain reaction.The cells incubated with 17β-estradiol (1nmol/L-100nmol/L,respectively) increased leptin mRNA and decreased adiponectin mRNA in a dose-related manner(P<0.05).The cultured cells stimulated by 100nmol/L 17β-E2 had significant higher mRNA expression of leptin(1.68 fold) and significant less adiponectin(51.8%) than that of control group.The cells incubated with 100nmol/L 17β-estradiol(12h-48h , respectively) increased leptin mRNA and decreased adiponectin mRNA in a time-related manner(P<0.05).3.Leptin mRNA correlated negatively with adiponectin mRNA level. Conclusion:1.Human preadipocytes are separated from adipocyte tissue by using collagenaseⅠand primary cultured successfully.The feasibility and practicability of the method have been verified by our experiments.This study lay the basis for further probing into the mechanisms which all kinds of hormones effect adipokines.2.Our results clearly demonstrate that 17β-estradiol can stimulate leptin mRNA and suppress adiponectin mRNA expression in human omental adipocytes in vitro.They make a deeper understanding about the sex specificities in obesity and 2 diebetes prevalence.