Fatty acid receptor modulator PBI-4050 inhibits kidney fibrosis and improves glycemic control
Yan Li, Sungjin Chung, Zhilian Li, Jessica M. Overstreet, Lyne Gagnon, Brigitte Grouix, Martin Leduc, Pierre Laurin, Ming-Zhi Zhang, Raymond C. Harris
Yan Li, Sungjin Chung, Zhilian Li, Jessica M. Overstreet, Lyne Gagnon, Brigitte Grouix, Martin Leduc, Pierre Laurin, Ming-Zhi Zhang, Raymond C. Harris
View: Text | PDF
Research Article Nephrology

Fatty acid receptor modulator PBI-4050 inhibits kidney fibrosis and improves glycemic control

Abstract

Extensive kidney fibrosis occurs in several types of chronic kidney diseases. PBI-4050, a potentially novel first-in-class orally active low–molecular weight compound, has antifibrotic and antiinflammatory properties. We examined whether PBI-4050 affected the progression of diabetic nephropathy (DN) in a mouse model of accelerated type 2 diabetes and in a model of selective tubulointerstitial fibrosis. eNOS–/– db/db mice were treated with PBI-4050 from 8–20 weeks of age (early treatment) or from 16–24 weeks of age (late treatment). PBI-4050 treatment ameliorated the fasting hyperglycemia and abnormal glucose tolerance tests seen in vehicle-treated mice. In addition, PBI-4050 preserved (early treatment) or restored (late treatment) blood insulin levels and increased autophagy in islets. PBI-4050 treatment led to significant improvements in lifespan in the diabetic mice. Both early and late PBI-4050 treatment protected against progression of DN, as indicated by reduced histological glomerular injury and albuminuria, slow decline of glomerular filtration rate, and loss of podocytes. PBI-4050 inhibited kidney macrophage infiltration, oxidative stress, and TGF-β–mediated fibrotic signaling pathways, and it also protected against the development of tubulointerstitial fibrosis. To confirm a direct antiinflammatory/antifibrotic effect in the kidney, further studies with a nondiabetic model of EGFR-mediated proximal tubule activation confirmed that PBI-4050 dramatically decreased the development of the associated tubulointerstitial injury and macrophage infiltration. These studies suggest that PBI-4050 attenuates development of DN in type 2 diabetes through improvement of glycemic control and inhibition of renal TGF-β–mediated fibrotic pathways, in association with decreases in macrophage infiltration and oxidative stress.

Authors

Yan Li, Sungjin Chung, Zhilian Li, Jessica M. Overstreet, Lyne Gagnon, Brigitte Grouix, Martin Leduc, Pierre Laurin, Ming-Zhi Zhang, Raymond C. Harris

×

Figure 2

PBI-4050 attenuated diabetic nephropathy (DN) and slowed loss of podocytes.

Options: View larger image (or click on image) Download as PowerPoint
PBI-4050 attenuated diabetic nephropathy (DN) and slowed loss of podocyt...
(A) PBI-4050 treatment attenuated glomerular injury in eNOS–/– db/db mice. **P < 0.01; n = 4 in vehicle-treated eNOS–/– db/db mice and n = 6 in PBI-4050–treated eNOS–/– db/db mice. Original magnification, ×400. (B) Podocyte number/glomerulus section was significantly higher in PBI-4050–treated eNOS–/– db/db mice than vehicle-treated eNOS–/– db/db mice when the mice were sacrificed at 20 weeks of age. ***P < 0.001 vs. baseline, †††P < 0.001 vs. vehicle group at 20 weeks of age; n = 5 in each group. Original magnification, ×400. PBI-4050 treatment attenuated tubulointerstitial fibrosis in eNOS–/– db/db mice as shown by Masson’s trichrome staining. Original magnification: Left, ×100; middle and right lane, ×400. All values are shown as mean ± SEM. P values were calculated by Student’s t test in A, and by ANOVA and Bonferroni’s t test in B.