ABSTRACT
OBJECTIVE@#To investigate the effect of cordyceps sinensis (CS) extract and losartan (Los) on the expression of Klotho (Kl), P53, P21, and apoptosis in renal tubular epithelial cell NRK-52E induced by angiotensin II (Ang II), and to elucidate its therapeutical mechanism in Ang II induced renal tubular epithelial cell apoptosis.@*METHODS@#NRK-52E cells were incubated with CS with or without Ang II for 24 hours. Experimental groups were divided according to the increasing concentrations of CS:0 (serving as controls), 5, 10, 20, 40, and 80 mg/L. The optimal concentration of CS was selected and cells were divided into 5 groups: controls, Ang II (1*10(-8) mol/L), Ang II (1*10(-8) mol/L)+CS (40 mg/L), Ang II (1*10(-8) mol/L)+Los (1*10(-5) mol/L), and Ang II (1*10(-8) mol/L)+CS (40 mg/L)+Los (1*10(-5) mol/L). After 24 hours, cell proliferation was evaluated by MTT assay. The mRNA and protein expression of Kl, P53 and P21 were measured by RT-PCR. Activity of caspase-3 was evaluated by caspase-3 activity assay Kit. Cell apoptosis was determined by Annexin V-FITC/PI double staining and flow cytometry.@*RESULTS@#Certain concentrations of CS promoted the proliferation of NRK-52E cells and increased cells proliferation inhibited by Ang II (P0.05).@*CONCLUSION@#CS can increase the expression of Kl down-regulated by Ang II, decrease P53 and P21 expression and caspase-3 activity, and reduce Ang II induced NRK-52E cell apoptosis, which may be part of its mechanism of the protective effects on hypertensive renal damage.
Subject(s)
Humans , Angiotensin II , Pharmacology , Apoptosis , Caspase 3 , Genetics , Metabolism , Cells, Cultured , Cordyceps , Chemistry , Cyclin-Dependent Kinase Inhibitor p21 , Genetics , Metabolism , Drugs, Chinese Herbal , Pharmacology , Epithelial Cells , Cell Biology , Metabolism , Glucuronidase , Genetics , Metabolism , Kidney Tubules , Cell Biology , Metabolism , Losartan , Pharmacology , RNA, Messenger , Genetics , Metabolism , Tumor Suppressor Protein p53 , Genetics , MetabolismABSTRACT
Objective To observe the Klotho expression in kidneys and renal tubular epithelial cells apoptosis in spontaneously hypertensive rats (SHRs) and the effects of cordyceps sinensis (CS), in order to study the mechanism of protective effects of CS on renal tubular cells apoptosis in hypertensive renal damage. Methods Twenty 22-week-old male SHRs were control group. After 8 weeks, the levels of 24 hours urinary protein (Upre), urinary N-acetyl-β-D-glucosaminidase (NAG), serum creatinine (Scr), blood urea nitrogen (BUN) and renal pathological changes were detected; the mRNA expression of Klotho, 053 and 021 was detected by RT-PCR; the protein expression of Klotho, 053, 021 and cleaved-caspase-3 was tested by Western blotting. TUNEL assay was applied to evaluate the renal tubular cell apoptosis. Results As compared to SHR group, the levels of 24 h urinary protein content [(52.16±29.3) mg, (49.97±32.5) mg, (54.67±30.09) mg vs (96.52±36.94) mg], urinary NAG [(44.13±9.11), (42.75±8.33), (41.96±7.88) U/L vs (54.07±6.57) U/L], Sct [(45.25±9.55), (43.76±8.65), (45.18±7.28) μmol/L vs (53.84±10.21) μmol/L]and BUN [(8.25±1.03), (8.40±1.58), (8.32±0.98) mmol/L vs (8.91±1.24) mmol/L]were decreased (all P<0.05), renal pathological changes were relieved, the levels of Klotho expression were up-regulated and the levels of p53 and p21 expression and cleaved-caspase-3 protein expression were down-regulated (all P<0.01), tubular cell apoptosis was decreased [7.56%±0.52%, 7.93%±0.37%, 7.37%±0.36% vs 13.32%±0.64%, P<0.01] in CS, Los and CS+Los group. Conclusions Klotho, p53 and p21 play important roles in renal tubular cells apoptosis in hypertensive renal damage. CS can up-regulate Klotho expression, down-regulate p53 and p21 expression and decrease the cleaved-caspase-3 expression and tubular cell apoptosis to ameliorate the hypertensive renal damage.