Yangchun Du1,2,3, Ming Zong3,4, Qiunong Guan3, Zhongli Huang1,3, Lan Zhou3,4, Jing Cai3, Gerald da Roza5, Hao Wang6, Hualin Qi7, Yiping Lu8, Caigan Du9. 1. Department of Urology, Institute of Urology, West China Hospital of Sichuan University, No. 17, Section 3, Ren Min Nan Road, Chengdu, 610041, China. 2. Organ Transplantation Center, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China. 3. Department of Urologic Sciences, University of British Columbia, 2660 Oak Street, Vancouver, BC, V6H 3Z6, Canada. 4. Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China. 5. Division of Nephrology, Department of Medicine, University of British Columbia, Vancouver, BC, Canada. 6. Department of General Surgery, Tianjin Medical University General Hospital, Tianjin, China. 7. Department of Nephrology, Shanghai Pudong New Area People's Hospital, No. 490 Chuanhuan South Road, Pudong New Area, Shanghai, 201299, China. qihualin@126.com. 8. Department of Urology, Institute of Urology, West China Hospital of Sichuan University, No. 17, Section 3, Ren Min Nan Road, Chengdu, 610041, China. yipinglu@163.com. 9. Department of Urologic Sciences, University of British Columbia, 2660 Oak Street, Vancouver, BC, V6H 3Z6, Canada. caigan@mail.ubc.ca.
Abstract
BACKGROUND: A long-term of peritoneal dialysis (PD) using a hypertonic PD solution (PDS) leads to patient's peritoneal membrane (PM) injury, resulting in ultrafiltration failure (UFF) and PD drop-out. Our previous study shows that PD effluent-derived mesenchymal stromal cells (pMSCs) prevent the PM injury in normal rats after repeated exposure of the peritoneal cavity to a PDS. This study was designed to compare the cytoprotection between pMSCs and umbilical cord-derived MSCs (UC-MSCs) in the treatment of both PM and kidney injury in uremic rats with chronic PD. METHODS: 5/6 nephrectomized (5/6Nx) Sprague Dawley rats were intraperitoneally (IP) injected Dianeal (4.25% dextrose, 10 mL/rat/day) and were treated with pMSCs or umbilical cord (UC)-MSCs (approximately 2 × 106/rat/week, IP). Ultrafiltration was determined by IP injection of 30 mL of Dianeal (4.25% dextrose) with 1.5-h dewell time, and kidney failure by serum creatinine (SCr) and blood urea nitrogen (BUN). The structure of the PM and kidneys was assessed using histology. Gene expression was examined using quantitative reverse transcription PCR, and protein levels using flow cytometric and Western blot analyses. RESULTS: We showed a slight difference in the morphology between pMSCs and UC-MSCs in plastic dishes, and significantly higher expression levels of stemness-related genes (NANOG, OCT4, SOX2, CCNA2, RAD21, and EXO1) and MSCs surface markers (CD29, CD44, CD90 and CD105) in UC-MSCs than those in pMSCs, but no difference in the differentiation to chondrocytes, osteocytes or adipocytes. pMSC treatment was more effective than UC-MSCs in the protection of the MP and remnant kidneys in 5/6Nx rats from PDS-induced injury, which was associated with higher resistance of pMSCs than UC-MSCs to uremic toxins in culture, and more reduction of peritoneal mesothelial cell death by the secretome from pMSCs than from UC-MSCs in response to PDS exposure. The secretome from both pMSCs and UC-MSCs similarly inactivated NOS2 in activated THP1 cells. CONCLUSIONS: As compared to UC-MSCs, pMSCs may more potently prevent PDS-induced PM and remnant kidney injury in this uremic rat model of chronic PD, suggesting that autotransplantation of ex vivo-expanded pMSCs may become a promising therapy for UFF and deterioration of remnant kidney function in PD patients.
BACKGROUND: A long-term of peritoneal dialysis (PD) using a hypertonic PD solution (PDS) leads to patient's peritoneal membrane (PM) injury, resulting in ultrafiltration failure (UFF) andPDdrop-out. Our previous study shows that PD effluent-derived mesenchymal stromal cells (pMSCs) prevent the PM injury in normal rats after repeated exposure of the peritoneal cavity to a PDS. This study was designed to compare the cytoprotection between pMSCs and umbilical cord-derived MSCs (UC-MSCs) in the treatment of both PM andkidney injury in uremicrats with chronic PD. METHODS: 5/6 nephrectomized (5/6Nx) Sprague Dawley rats were intraperitoneally (IP) injectedDianeal (4.25% dextrose, 10 mL/rat/day) and were treated with pMSCs or umbilical cord (UC)-MSCs (approximately 2 × 106/rat/week, IP). Ultrafiltration was determined by IP injection of 30 mL of Dianeal (4.25% dextrose) with 1.5-h dewell time, andkidney failure by serum creatinine (SCr) and bloodureanitrogen (BUN). The structure of the PM and kidneys was assessed using histology. Gene expression was examined using quantitative reverse transcription PCR, and protein levels using flow cytometric and Western blot analyses. RESULTS: We showed a slight difference in the morphology between pMSCs and UC-MSCs in plastic dishes, and significantly higher expression levels of stemness-related genes (NANOG, OCT4, SOX2, CCNA2, RAD21, andEXO1) and MSCs surface markers (CD29, CD44, CD90 andCD105) in UC-MSCs than those in pMSCs, but no difference in the differentiation to chondrocytes, osteocytes or adipocytes. pMSC treatment was more effective than UC-MSCs in the protection of the MP and remnant kidneys in 5/6Nx rats from PDS-induced injury, which was associated with higher resistance of pMSCs than UC-MSCs to uremic toxins in culture, and more reduction of peritoneal mesothelial cell death by the secretome from pMSCs than from UC-MSCs in response to PDS exposure. The secretome from both pMSCs and UC-MSCs similarly inactivatedNOS2 in activatedTHP1 cells. CONCLUSIONS: As compared to UC-MSCs, pMSCs may more potently prevent PDS-inducedPM andremnant kidney injury in this uremic rat model of chronic PD, suggesting that autotransplantation of ex vivo-expandedpMSCs may become a promising therapy for UFF anddeterioration of remnant kidney function in PDpatients.