Galectin-3 Blockade Reduces Renal Fibrosis in Two Normotensive Experimental Models of Renal Damage

RESEARCH ARTICLE Galectin-3 Blockade Reduces Renal Fibrosis in Two Normotensive Experimental Models of Renal Damage Ernesto Martinez-Martinez1, Jaime Ibarrola1, Laurent Calvier2, Amaya Fernandez-Celis1, Celine Leroy2, Victoria Cachofeiro3, Patrick Rossignol2, Natalia Lopez-Andres1,2* a11111 1 Cardiovascular Translational Research. Navarrabiomed (Miguel Servet Foundation), Instituto de Investigación Sanitaria de Navarra (IdiSNA), Pamplona, Spain, 2 INSERM, Centre d’Investigations CliniquesPlurithématique 1433, UMR 1116 Université de Lorraine, CHRU de Nancy, French-Clinical Research Infrastructure Network (F-CRIN) INI-CRCT, Nancy, France, 3 Department of Physiology, School of Medicine, Universidad Complutense, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain * Abstract OPEN ACCESS Citation: Martinez-Martinez E, Ibarrola J, Calvier L, Fernandez-Celis A, Leroy C, Cachofeiro V, et al. (2016) Galectin-3 Blockade Reduces Renal Fibrosis in Two Normotensive Experimental Models of Renal Damage. PLoS ONE 11(11): e0166272. doi:10.1371/journal.pone.0166272 Editor: Philippe Rouet, I2MC INSERM UMR U1048, FRANCE Background Galectin-3 (Gal-3), a β-galactoside-binding lectin, is increased in kidney injury and its pharmacological blockade reduces renal damage in acute kidney injury, hyperaldosteronism or hypertensive nephropathy. We herein investigated the effects of pharmacological Gal-3 inhibition by modified citrus pectin (MCP) in early renal damage associated with obesity and aortic stenosis (AS). Results Received: September 13, 2016 Accepted: October 25, 2016 Published: November 9, 2016 Copyright: © 2016 Martinez-Martinez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: Our data can be found in the paper and in the supporting information file. Funding: This work was supported by Miguel Servet contract CP13/00221 from the “Instituto de Salud Carlos III-FEDER”, Fondo de Investigaciones Sanitarias [PI15/02160] “One way to make Europe”, FIBROTARGETS project (Grant agreement number FP7 #602904), Red de Investigación Cardiovascular del ISCIII (RIC; RD12/0042/0033), Plan Estatal I+D+I 2013-2016. PR was supported by the RHU Fight-HF, a public grant overseen by Gal-3 was upregulated in kidneys from high fat diet (HFD) rats and in animals with partial occlusion of ascending aorta (AS). Urinary and plasma neutrophil gelatinase-associated lipocalin (NGAL) and urinary albumin were enhanced in HFD and AS rats. In kidney from obese rats, fibrotic markers (collagen, TFG-β), epithelial-mesenchymal transition molecules (α-smooth muscle actin, E-cadherin), inflammatory mediator (osteopontin) and kidney injury marker (kidney injury molecule-1) were modified. In kidney from AS rats, fibrotic markers (collagen, CTGF), epithelial-mesenchymal transition molecules (fibronectin, α-smooth muscle actin, β-catenin, E-cadherin) and kidney injury markers (NGAL, kidney injury molecule1) were altered. Histologic observations of obese and AS rat kidneys revealed tubulointerstitial fibrosis. The pharmacological inhibition of Gal-3 with MCP normalized renal Gal-3 levels as well as functional, histological and molecular alterations in obese and AS rats. Conclusions In experimental models of mild kidney damage, the increase in renal Gal-3 expression paralleled with renal fibrosis, inflammation and damage, while these alterations were prevented by Gal-3 blockade. These data suggest that Gal-3 could be a new player in renal molecular, histological and functional alterations at early stages of kidney damage. PLOS ONE | DOI:10.1371/journal.pone.0166272 November 9, 2016 1 / 11 Galectin-3 Blockade in Renal Damage the French National Research Agency (ANR) as part of the second “Investissements d’Avenir” programme (reference: ANR-15-RHUS-0004). Competing Interests: The authors have declared that no competing interests exist. Introduction Chronic kidney disease (CKD) represents a significant global health problem with few therapeutic options currently known to slow its progression [1, 2]. Progressive impaired renal function results from a triad of glomerular sclerosis, tubulointerstitial fibrosis and vascular sclerosis [3]. Subclinical tubulointerstitial fibrosis may be important in the early stages of CKD [4]. The pathogenesis of renal interstitial fibrosis is driven by reorganisation of cellular interactions with the extracellular matrix, fibroblast activation, inflammation and it is characterized by an epithelial to mesenchymal transition (EMT) [5]. EMT is promoted by cytokines such as transforming growth factor beta 1 (TGF-β1) or connective tissue growth factor (CTGF) [5]. CKD is prevalent in metabolic syndrome, insulin resistance and obesity [6]. CKD can develop in obese individuals, pointing out the importance of an early detection and prevention. Obesity is associated with tubulointerstitial fibrosis which correlates with the degree of albuminuria and the progression of CKD [6]. CKD can develop in patients undergoing aortic valve replacement [7]. Aortic stenosis (AS) impairs forward blood flow from the heart, causing a chronic hypoperfusion state resulting in CKD [7]. Moreover, severe AS is one mechanism responsible for an impaired glomerular filtration rate [8]. Galectin-3 (Gal-3) is a member of β-galactoside-binding lectins which is characterized by carbohydrate recognition domain. Gal-3 has been linked to the development of renal fibrosis in animal models and it is inversely correlated with estimated glomerular filtration rate in humans [9, 10]. Elevated serum levels of Gal-3 have been associated with a higher risk of incident CKD and renal dysfunction, suggesting that Gal-3 can predict renal damage, years before CKD is detected clinically, facilitating targeted treatment and disease prevention [10]. Modified citrus pectin (MCP) (a complex water soluble indigestible polysaccharide riche in β-galactose) is a Gal-3 inhibitor that blocks the lectin’s activity. Our group has recently demonstrated that Gal-3 inhibition improves renal remodeling in hyperaldosteronism [11]. Moreover, Gal-3 inhibition is beneficial in acute kidney injury [12] and protects against hypertensive nephropathy [13]. The aim of this study was to highlight the effects of Gal-3 inhibition in early stages of mild kidney damage, using two different normotensive pathophysiological animal models: obese rats and AS rats. Materials and Methods Animals Adult male Wistar rats weighing 150g were obtained from Harlan Ibérica. The first set of animals received either a high-fat diet (HFD, 33.5% fat; Harlan Teklad #TD.03307, MN, USA; n = 16) or a standard diet (3.5% fat; Harlan Teklad #TD.2014, MN, USA; n = 16) for 6 weeks. Half of the animals of each group received the Gal-3 activity inhibito (...truncated)