Fatemeh Zal1, Zohreh Mostafavi-Pour2, Afagh Moattari3, Ahmadreza Sardarian4, Mahmood Vessal5. 1. 1)Infertility Research Center, Shiraz University of Medical Sciences, Shiraz, Iran. 2)Reproductive Biology group, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran.zmostafavipour@yahoo.co.uk. 2. 3)Maternal-fetal Medicine Research Center, Shiraz University of Medical Sciences, Shiraz, Iran. 4)Recombinant Protein Laboratory, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran. 3. 5)Microbiology Department, Medical School, Shiraz University of Medical Sciences, Shiraz, Iran. 4. Student Research Committee, Resident of Orthodontics, Department of Orthodontics, Dental School, Shiraz University of Medical Sciences, Shiraz, Iran. 5. Department of Biochemistry, Fars Science and Research Branch, Islamic Azad University, Fars, Iran.
Abstract
BACKGROUND: Nephrotoxicity is considered a significant cause of patient morbidity following chronic Cyclosporine A (CsA) treatment. The exact mechanism of CsA-induced nephrotoxicity remains to be fully clarified. Tubulointerstitial fibrosis is widely regarded as a major pathway of CsA toxicity; therefore, the role of integrins as regulators of collagen in the extra-cellular matrix can be deemed pivotal. The objective of the present study was to observe the expression levels of alpha2beta1 integrin following CsA treatment +/- antioxidants. METHODS: Adhesion assay, immunofluorescent and flow cytometric analyses were performed on kidney fibroblasts obtained from rats after administration of CsA (25 mg/kg/day) +/- Vitamin E (vit. E) and Quercetin (Q) for 4 weeks. Total RNA was collected from the aforementioned fibroblasts for semi-quantitative reverse transcriptase-polymerase chain reaction analysis of α2 and β1 integrins. RESULTS: We found that α2 and β1 integrins were both markedly reduced following treatment with CsA, i.e., 25% and 13%, respectively, but were normal following subsequent consumption of the antioxidants vit. E and Q. Attachment and spreading of the CsA-treated fibroblasts declined from 82% to 50%; however, this effect was partially reversed to 70% following antioxidant treatment. Similar results were observed in the spreading assay in which the level of spreading decreased from 73% to 21% and was subsequently restored to 46%. CONCLUSION: We conclude that cell adhesion, mediated by binding of integrin to collagen, which is a prerequisite of normal cell viability and collagen regulation, may be a novel pathway further explaining the nephrotoxic effects of CsA.
BACKGROUND:Nephrotoxicity is considered a significant cause of patient morbidity following chronic Cyclosporine A (CsA) treatment. The exact mechanism of CsA-induced nephrotoxicity remains to be fully clarified. Tubulointerstitial fibrosis is widely regarded as a major pathway of CsAtoxicity; therefore, the role of integrins as regulators of collagen in the extra-cellular matrix can be deemed pivotal. The objective of the present study was to observe the expression levels of alpha2beta1 integrin following CsA treatment +/- antioxidants. METHODS: Adhesion assay, immunofluorescent and flow cytometric analyses were performed on kidney fibroblasts obtained from rats after administration of CsA (25 mg/kg/day) +/- Vitamin E (vit. E) and Quercetin (Q) for 4 weeks. Total RNA was collected from the aforementioned fibroblasts for semi-quantitative reverse transcriptase-polymerase chain reaction analysis of α2 and β1 integrins. RESULTS: We found that α2 and β1 integrins were both markedly reduced following treatment with CsA, i.e., 25% and 13%, respectively, but were normal following subsequent consumption of the antioxidants vit. E and Q. Attachment and spreading of the CsA-treated fibroblasts declined from 82% to 50%; however, this effect was partially reversed to 70% following antioxidant treatment. Similar results were observed in the spreading assay in which the level of spreading decreased from 73% to 21% and was subsequently restored to 46%. CONCLUSION: We conclude that cell adhesion, mediated by binding of integrin to collagen, which is a prerequisite of normal cell viability and collagen regulation, may be a novel pathway further explaining the nephrotoxic effects of CsA.