*4.1.8. Transforming growth factor-b1*

Transforming growth factor-b1 (TGF-b1) is a potent fibrogenic growth factor that may play a significant role in pathogenesis of SN [134]. It is a peptide of low molecular weight and has pleiotropic action. In the kidneys, it stimulates fibrogenesis through enhanced production of extracellular matrix proteins and nephron loss by various mechanisms, such as apoptosis of endothelial cells and podocytes [135]. Whether the urinary levels of TGF-b1 has a diagnostic significance in the early prediction of SN in children with SCD is still to be determined [136]. However in the article published by Sundaram et al. [57], urinary TGF-β was present at very low to undetectable levels in their patient population and showed no association with the degree of albuminuria. These data are in contrast with those published by Ghobrial et al. [137]. In their study, the authors have found a strong positive correlation between urinary TGF-b1 and urinary proteins and eGFR in all groups of SCD patients studied.
