TGFB1 and glomerulosclerosis: TGF‐β1 is also a pleiotropic and multifunctional cytokine with profibrotic actions and is known to be upregulated in the kidneys of CS‐exposed subjects and plays a major role in the development of progressive glomerulosclerosis and interstitial fibrosis (Elliot et al., 2006; Mur et al., 2004).