Mo044inhibin a and Decorin Secreted by Adult Renal Stem/Progenitor Cells Through the Tlr2 Engagement Induce Renal Tubular Cell Regeneration

Abstract

Introduction and Aims: Acute kidney injury (AKI) is emerging as a public health problem worldwide. Several pharmacologic therapies that can accelerate recovery and improve survival have been attempted and were efficacious in experimental models but failed to manifest any substantial beneficial effect in clinical practice. Recent studies showed that adult renal progenitor cells (ARPCs) can participate in kidney repair processes and might be potentially used in the clinic to improve regeneration in acute and progressive kidney disease. Our aim was to study the influence of ARPCs on the regenerative process of cisplatin-injured renal proximal tubular epithelial cells (RPTECs) and validate some the ARPC-secreted molecules able to induce regenerative processes. Methods: CD133-positive ARPCs were isolated by magnetic sorting, starting from healthy sections of kidney removed for renal carcinoma. An in vitro model of cisplatin induced cell toxicity, in which RPTECs were co-cultured with ARPCs, was used. Caspase 3 expressions was studied to evaluate apoptosis. Cell proliferation induced by ARPCs was evaluated by BrdU proliferation assay. ELISA assays were performed to evaluate inhibin-A (INHB-A), decorin (DCN) and FGF2 chemokines. A natural polymer-based nanosystem for efficacious delivery of molecules was developed. INHB-A-loaded Polysaccharides Synthetic Vesicles (INHB-A-PSSV) and DCN-loaded Polysaccharides Synthetic Vesicles (DCN-PSSV) were synthesized by two steps methods: ionotropic pre-gelation of alginate core, followed by chitosan polyelectrolyte complexation. A microfluidic device was appositely fabricated in order to optimize the INHB-A and DCN-PSSV at interface-assembly process, in terms of polymers and INHB-A and DCN amount as well as vesicles size distribution. Cellular uptake and INHB-A-PSSV and DCN-PSSV effectiveness were tested. Results: We showed that the induction of tubular cell regeneration process was specific of tARPCs and occured only after that they detect the damage. On the contrary, glomerular ARPCs could not induce RPTEC regeneration. tARPCs protected RPTEC and HK2 cells from cisplatin toxicity by preventing cisplatin-induced apoptosis and enhancing proliferation of survived cells. Regenerative effect was completely abrogated blocking the Toll-like receptor 2 (TLR2), or using tARPC not expressing the TLR2. We found that INHB-A, DCN and FGF2 were secreted by ARPCs following the damage of RPTEC and that they were involved in the RPTEC regeneration. We showed that addition of INHB-A and DCN PSSV to cisplatin-treated RPTECs led to a substantial increase in cell number and viability after 3 days of culture. Remarkably, a very low dosage of functional loaded proteins (8 ng/25 ul) was sufficient to induce cell regeneration and the percentage of viable cells was similar to that of RPTECs without damage. Conclusions: We demonstrated that tARPCs have a regenerative effect on damaged RPTEC, by both preventing apoptosis and enhancing proliferation of surviving cells. They act by means of their secretoma, t...

Reduced urine volume and changed renal sphingolipid metabolism in P2ry14-deficient mice

“…Similar results were observed by overexpressing decorin in rat skeletal muscle in vivo (Isaka et al, 1996). Furthermore, decorin seems to be involved in regenerative processes in the kidney (Sallustio et al, 2017). Decorin binds and neutralizes TGF-β which is thought to be a central pathway in tissue fibrosis (Isaka et al, 1996).…”