Proapoptotic effect of angiotensin II on renal tubular epithelial cells and protective effect of Cordyceps sinensis / 中南大学学报(医学版)

OBJECTIVE@#To investigate the mechanism of the protective effect of Cordyceps sinensis (C. sinensis) on the apoptosis of cultured NRK-52E induced by angiotension II (AngII).@*METHODS@#NRK-52E cells were incubated with C. sinensis (0, 5, 10, 20, and 40 mg/L) and 10(-8) mol/ L AngII for 24, 48, 72 h. The optimal concentration of C. sinensis was selected. Either NRK-52E cells were incubated with different doses of AngII (0, 10(-12), 10(-10), 10(-8), and 10(-6) mol/L) for 24 h, or with 10(-8) mol/L AngII for 24, 48, and 72 h, to observe the effect of AngII on the apoptosis of NRK- 52E cells. The optimal concentration and time of AngII were selected. In another experiment cells were divided into 5 groups: a control, AngII (10(-8) mol/L), AngII (10(-8) mol/L)+ C. sinensis (40 mg/ L), Ang II (10(-8) mol/L)+ fosinopril (10(-5) mmol/L), and Ang II (10(-8) mol/L)+ fosinopril (10(-5) mol/ L)+C. sinensis (40 mg/L). MTT assay was used to test the changes in the proliferation of NRK-52E cultured with different concentration of C. sinensis for 24, 48, 72 h. The Annecxin V-FITC and PI stainings were applied to detect the apoptosis rate induced by AngII by flow cytometer (FCM) and to determine the eddects of C. sinensis. The activity of caspase-3 was assayed by spectrophotometry.@*RESULTS@#Certain concentrations of C. sinensis (10-40 mg/L) promoted the proliferation of NRK- 52E cells inhibited by AngII(P0.05).@*CONCLUSION@#C. sinensis can suppress the apoptosis of NRK-52E by AngII, and the protective effect of C. sinensis may be inhibiting the activation of caspase-3 during the AngII-induced apoptosis of NRK-52E.

Effect of ceramide on peritoneal mesothelial cells apoptosis induced by peritoneal dialysis solution / 中华肾脏病杂志

ObjectiveToexploretheeffectof ceremideonprocess of peritoneal mesothelial cells(PMCs) apoptosis induced by peritoneal dialysis solution(PDS).Methods PMCs were cultured with normal DMEM,1.5％ PDS and 4.25％ PDS.4.25％ mannitol was used as high osmotic pressure control.Ceremide were detected by LC-MS-MS.Flow cytometry was used in apoptosis analysis.Bax,p53 and bcl-2 protein expressions were detected by Western blotting.Results (1) PDS caused the increase of intracellular ceremide in PMCs,and normal and high osmotic pressure controls had no such effect.As the acidic sphigomyelinase inhibitor,desipramine significantly inhibited the production of ceramide induced by 4.25％ PDS [(56.08±12.24) μg/L vs (91.25:t:15.89) μg/L,P＜0.01]. (2) Compared with 1.5％ PDS,4.25％ PDS stimulated PMCs apoptosis (26.65％±6.21％ vs 4.04％±1.86％,P＜0.01),up-regulated bax and p53 proteins expression (P＜0.01),and down-regulated bcl-2 protein exprssion(P＜0.05).Desipramine obviously inhibited the apoptosis induced by 4.25％ PDS,decreased bax and p53 proteins expression,increased bcl-2 protein expression(P＜0.05).Exogenous C2-ceremide reversed the effect of desipramine(P＜0.05).Conclusion The increase of intracellular ceremide may play an important role in the PMCs apoptosis induced by high glucose PDS.

The effect of hyperglycemia on the expression of Toll-like receptor 4 in renal tubular epithelial cells / 中国医师杂志

Objective This study was designed to explore the effect of hyperglycemia on the expression of Toll-like receptor 4 (TLR4 ) in renal tubular epithelial cells and its significance in diabetic nephropathy. Methods In vitro cultured renal tubular epithelial cells ( NRK-52E) were divided into LG group (cultured in 5mmol / L glucose DMEM) and HC group (cultured in 25mmol / L glucose DMEM). Cells were harvested at different time points. Immunohistochemistry, Rt-PCR, Western Blot were used to detect TLR4 protein and mRNA expression, and the levels of IL-6 and TNF-α from the cell culture supernatant were determined by EL1SA assay. Results After 6 hours, there was increased expression TLR4 mRNA in HC group, which appeared to be maintained for 24 hours and began to decrease after 48 hours ( P < 0.05). TLR4 protein expression increased in HC group after 24 hours, and increased even further after 48 hours. Compared with LG groups, the difference had statistical significance ( P <0.05). In HG group, IL-6 and TNF-α expression in the supernatant from the NRK-52E culture were significantly increased ( P < 0.05) , and the expression of IL-6 and TNF-α was positive correlated with the expression of TLR4 protein ( r =0.799,0.820). Conclusion High glucose triggers an increase in expression of TLR4 in NRK-52E cells, itself leading to an increase in expression of inflammatory factors such as TNF-α and IL-6. In this way, TLR4 participates in the progress of diabetic nephropathy.

Effect of cordyceps sinensis extract on Klotho expression and apoptosis in renal tubular epithelial cells induced by angiotensin II / 中南大学学报(医学版)

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.

Effects of cordyceps sinensis on Klotho expression in kidneys and apoptosis in renal tubular epithelial cells of spontaneously hypertensive rats / 中华肾脏病杂志

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.

Expression of adiponectin mRNA in adipose tissues of spontaneously hypertensive rat and effects of fosinopril and valsartan / 中国医师杂志

Objective To investigate the expression of adiponectin Mrna in adipose tissues of spontaneously hypertensive rats (SHR) and the effects of Fosinopril (Fos) and osartan (Los) on adiponectin Mrna.Methods Twenty 22 - week old male SHR rats were randomly divided into four groups:SHR group,Fos group,and Fus + Los group.Five 22 - week old male WKY rats were used as control.The body weigh,cuff-tail blood pressure,urinary microprotein and urinary N-acetyl-β-D-glucesaminidase were determined.RT-PCR were applied to determine the expression of adiponectin Mrna in adipose tissues.Results At the eighth week,systolic blood pressure of rats in SHR group was significantly higher than those in the other four groups (P＜0.05).The levels of urinary microprotein,urinary NAGase in the WKY group,Fos group,Los group and Fos + Los group were significantly lower than those in SHR group(P＜0.05).RT-PCR analysis revealed that the expression of adiponectin Mrna in SHR group was obviously decreased,compared with WKY goup.Adiponectin Mrna expression in Los group,Fos group and Fos + Los group were increased compared with SHR group(P＜0.05).Conclusions The expression of adiponeetin Mrna is down-regulated in adipose tissues of SHR.After intervention with Fusinopril and Losartan,the adiponectin Mrna expression was up-regulated in adipose tissues of SHR,the levels of urinary microprotein and urinary NAGase were obviously increased in SHR and the levels of urinary microprotein and urinary NAGase were obviously decreased.