Dulaglutide Mitigates High Dietary Fructose-Induced Renal Fibrosis in Rats Through Suppressing Epithelial-Mesenchymal Transition Mediated by GSK-3β/TGF-β1/Smad3 Signaling Pathways.

Aims: High dietary fructose consumption has been linked to the development of renal fibrosis. Dulaglutide is a long acting glucagon like peptide-1 (GLP-1) analog, showing some renoprotective properties; however its action on renal fibrosis remains uncertain. We investigated the effect of dulaglutide on fructose-induced renal fibrosis in comparison to pirfenidone, as well-established anti-fibrotic drug, and the contribution of epithelial-mesenchymal transition (EMT) process and its upstream signaling. Main methods: Six week-old male Wistar albino rats received 10%w/v fructose solution in drinking water for 24 weeks and co-treated with either pirfenidone (100 mg/kg/day, orally) or dulaglutide (0.2 mg/kg/week, s.c) for the last four weeks. Lipid profile, glucose homeostasis, kidney functions were assessed. Kidneys were harvested for biochemical and histological analyses. Key findings: High dietary fructose consumption for 24 weeks induced insulin resistance, dyslipidemia and renal dysfunction that were ameliorated by dulaglutide and pirfenidone to lesser extent. Histological examination revealed histological lesions and interstitial fibrosis in renal sections of high fructose-fed rats, which were reversed by dulaglutide or pirfenidone treatment. Both drugs modulated the EMT-related proteins by increasing the epithelial marker, E-cadherin, while suppressing the mesenchymal markers, vimentin and alpha-smooth muscle actin (a-SMA) in renal tissue. Moreover, both drugs attenuated fructose-induced upregulation of GSK-38/TGF-81/Smad3 signaling. Significance: These findings suggest that dulaglutide can emerge as a promising therapeutic agent for fructose -induced renal fibrosis. These results add mechanistic insights into the anti-fibrotic action of dulaglutide through suppressing EMT and the upstream GSK-38/TGF-81/Smad3 signaling.