Effects Of Spironolactone On Aldosterone Or High Glucose Induced CTGFmRNA And Protein Expression In The Glomerular Mesangial Cells Of Rat

Objective: To study the renoprotection mechnisms of spironolactone(SPI) by observing its effect on the expression of connective tissue growth factor(CTGF) mRNA and protein in rat mesangial cells(MsC) cultured in aldosterone(ALD) or high glucose(HG) induced state.Methods: MsC were divided into following groups: Group A: the normal glucose group (NG, 5.6mmol/L Glu) High glucose(HG) group: Group B1: High glucose (HG, 30mmol/L Glu) Group B2: HG+10^-7mol/L SPI; Group B3: HG+10^-8mol/L SPI; Group B4: HG+10^-9mol/L SPI。Ald groups: Group C1: NG+10^-7mol/L Ald Group C2: NG+10^-7 mol/L Ald +10^-7mol/L SPI; Group C3: NG+10^-7 mol/L Ald +10^-8mol/L SPI; Group C4: NG+10^-7 mol/L Ald +10^-9mol/L SPI。After 48 hours' incubation, the MsC and its supernatant were analyzed by reverse transcription polymerase chain reaction(RT-PCR) and enzyme linked immunosorbent assay (ELISA) to observe the changes of CTGF mRNA and CTGF protein expressions and the expressions of MR and 11β-HSD2 mRNA in mesangial cell.Results:(1)MsC expressed MR, 11β-HSD2 mRNA, CTGF mRNA and protein in normal glucose condition measured by RT-RCR and ELISA. (2)At the 48h, the CTGF mRNA in the MsC and CTGF protein values in the supernatant that cultured with high glucose or 10^-7mol/L ALD increased significantly compared to the normal group(P<0.05).(3) ALD induced CTGFmRNA and protein expressions of MsC markedly down-regulated in 10^-9 -10^-7mol/L SPI-treated group. However, in high glucose condition, there was no statistical diference in the levels of CTGFmRNA between group 10^-9 mol/L SPI-treated group and the normal group (P>0.05).(4)After intervented with different concentration SPI, the CTGFmRNA expression and protein secretion of MsC still were not restored to those of the normal group in HG group and aldosterone induced group.(5)Spironolactone in the range of concentrations from 10^-8 to 10^-7mol/L had a capability of inhibiting CTGF mRNA and protein expressions of MsC induced by HG and 10^-7 mol/L ALD in MsC, and 10^-9 mol/L SPI had a inhibitory effect on the CTGF mRNA and protein expressions of MsC induced by10^-7 mol/L ALD , but not by HG.Conclusions Spironolactone could down-regulate the CTGF mRNA and protein expression induced by ALD and HG in glomerlar MsC of rat, which may provide an experimental evidence for further evaluating the possible protective effect of SPI against diabetic nephropathy.