Citation: Melo, Z.; Palomino, J.; Franco-Acevedo, A.; García, D.; González-González, R.; Verdugo-Molinares, M.G.; Portilla-de Buen, E.; Moreno-Carranza, B.; Fuentes-Orozco, C.; Barbosa-Camacho, F.J.; et al. Pharmacological Blockade of TGF-Beta Reduces Renal Interstitial Fibrosis in a Chronic Ischemia–Reperfusion Animal Model. Drugs Drug Candidates 2023, 2, 137–147. https://doi.org/10.3390/ ddc2010009 Academic Editor: Jean Jacques Vanden Eynde Received: 24 November 2022 Revised: 28 February 2023 Accepted: 8 March 2023 Published: 13 March 2023 Copyright: © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). Article Pharmacological Blockade of TGF-Beta Reduces Renal Interstitial Fibrosis in a Chronic Ischemia–Reperfusion Animal Model Zesergio Melo 1, * , Julio Palomino 2 , Adriana Franco-Acevedo 3 , David García 2 , Ricardo González-González 2 , Maritza G. Verdugo-Molinares 4 , Eliseo Portilla-de Buen 2 , Bibiana Moreno-Carranza 5 , Clotilde Fuentes-Orozco 6 , Francisco J. Barbosa-Camacho 6 , Emilio A. Reyes-Elizalde 6 , Laura Cortés-Sanabria 6 and Alejandro González-Ojeda 6, * 1 CONACYT-Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara 44340, Mexico 2 Centro de Investigación Biomédica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara 44340, Mexico; juliopalominop8@gmail.com (J.P.); davidga28@gmail.com (D.G.); qfbragg26@gmail.com (R.G.-G.); dreportilla@gmail.com (E.P.-d.B.) 3 Department of Pathology and Laboratory Medicine, University of California, Los Angeles, CA 90095, USA; ady_francoa@hotmail.com 4 Maestría en Ciencias en Innovación Biotecnológica, Centro de Investigación y Asistencia en Tecnologíay Diseño del Estado de Jalisco, Guadalajara 44270, Mexico; maverdugo_al@ciatej.edu.mx 5 Escuela de Medicina, Universidad Anáhuac Querétaro, Queretaro 76246, Mexico; bibianamorenocarranza@gmail.com 6 Unidad de Investigación Biomédica 02, Hospital de Especialidades, Centro Médico Nacional de Occidente, Instituto Mexicano del Seguro Social, Guadalajara 44349, Mexico; clotilde.fuentes@gmail.com (C.F.-O.); efebeka_@hotmail.com (F.J.B.-C.); dreyes.emilio@gmail.com (E.A.R.-E.); cortes_sanabria@yahoo.com.mx (L.C.-S.) * Correspondence: zcmelo@conacyt.mx (Z.M.); avygail5@gmail.com (A.G.-O.); Tel.: +52-3331294165 (A.G.-O.) Abstract: The targeting of transforming growth factor β (TGF-β) has been shown to reduce compli- cations related to ischemia-reperfusion injury (IRI) post-surgically. Pirfenidone (PFD) specifically inhibits TGF-β expression and has been demonstrated to provide protection from IRI in short-term allograft models, though not yet in long-term models. A chronic unilateral IRI model was established using male Wistar rats. The animals were divided into two groups: one with IRI and a pre-treatment of PFD (0.5 mg/kg) followed by 0.5 mg/kg/day of orally administered PFD for 30 days, and a control group without PFD treatment. A sham group was also included. Kidneys and blood samples were collected after 30 days, and the renal function was evaluated by measuring the serum creatinine and KIM-1 levels. RT-PCR was used to analyze fibrosis-related genes, and Luminex to quantify the pro-inflammatory serum IL-18 cytokine. Renal section staining and histological analysis were used to detect collagen deposits. Comparison within the groups showed an increase in serum creatinine and KIM-1 expression after IRI in the control group, while PFD reduced COLL1A1 and TGF-β expression and demonstrated a reduction in fibrosis through histological stains. The treatment group also showed a reduction in IL-18. Our results suggest that PFD exerts protective effects on chronic renal IRI, reducing fibrosis development and inflammation. This study provides new insights into the treatment and management of chronic renal function loss after IRI. Keywords: pirfenidone; transforming growth factor β; interstitial fibrosis; renal ischemia–reperfusion; chronic kidney disease 1. Introduction A rapid reduction in kidney function may progress to chronic kidney disease. Nowa- days, there is no curative treatment for patients with end-stage chronic kidney disease, and the only remaining therapeutic option is kidney transplantation [1]. Nevertheless, Drugs Drug Candidates 2023, 2, 137–147. https://doi.org/10.3390/ddc2010009 https://www.mdpi.com/journal/ddc