Figure 2

Metformin suppresses renal inflammation and fibrosis in Col4a5 G5X Alport syndrome mice. (a) Staining of renal sections of 20-week-old mice by PAS, Masson-Trichrome, and F4/80 immunohistochemistry (IHC) indicated renal inflammation was ameliorated in losartan- or metformin-treated C57BL/6 Col4a5 G5X Alport syndrome mice. Scale bars, PAS 50 μm; MT and F4/80 200 μm. (b) Glomerular injury scores were evaluated based on the PAS-stained sections. The severity of glomerulosclerosis was decreased in losartan- or metformin-treated C57BL/6 Col4a5 G5X Alport syndrome mice. (c) Tubulointerstitial fibrosis scores were evaluated based on the MT-stained sections. The fibrotic region was reduced in losartan- or metformin-treated C57BL/6 Col4a5 G5X Alport syndrome mice. (d) F4/80-positive region was evaluated based on the F4/80 IHC section. Both losartan and metformin suppressed the infiltration of macrophages. (e–l) Total RNA was isolated from renal tissues of 20-week-old mice, and subjected to quantitative RT-PCR. The data were normalized to Gapdh. Data are expressed as the means ± S.E. in WT (n = 5), vehicle-, losartan-, and metformin-treated C57BL/6 Col4a5 G5X Alport syndrome mice (n = 8–9 per group). P values were assessed by Dunnett’s test (^##P < 0.01 vs WT. *P < 0.05, **P < 0.01 vs vehicle). (m) Whole kidney lysates were analyzed by immunoblotting. The full-length blots are presented in Supplementary Fig. S11. (n,o) The relative amount of proteins was quantified. Bars indicate the mean ± S.E. (n = 4 per group). P values were assessed by Dunnett’s test (*P < 0.05, **P < 0.01 vs vehicle).