Study on the injury mechanism of Ang-Ⅱ to mice podocyte in the high glucose environment / 中国医师杂志

ABSTRACT

Objective To cultivate mice glomerular podocyte with high glucose and high Ang-Ⅱ,observe the morphocytology of podocyte,and investigate protein kinase C (PKC) activity,the expressions of nephrin and CD2-associated protein (CD2AP),and apoptosis of podocyte with injuries cultivations.Methods The conditions immortalization mice podocyte cell lines was cultivated,after passage and differential induce,the cell lines was divided into six groups:normal group,high glucose group,high Ang-Ⅱ] group,the above two mixed group,intervened group of PKC inhibitor,and hypertonic group.After 72 hours,cell apoptosis rate was detected with flow cytometer; PKC activity was detected with enzyme linked immunosorbent assay (ELISA) in 24 hours and 48 hours ; The expressions of nephrin and CD2AP mRNA were detected by real time-polymerase chain reaction (RT-PCR).Results (1)After 24 hours,the PKC of high glucose group and high Ang-Ⅱ group were more activated than normal group [(47.09 ± 1.19) pmol/L,(42.93 ±0.71) pmol/L,P ＜0.05].The activated phenomenon was more obvious in the mixed group.Compared to 24 hours [(58.75 ±0.71) pmol/ L,P ＜ 0.01],PKC was more activated in 48 hours (P ＜ 0.05).(2) Nephrin mRNA was reduced in podocyte exposed to high glucose and high Ang-Ⅱ at least 24 hours (56.87 ± 0.74,48.54 ± 0.86,P ＜ 0.05),and was reduced more in mixed group (11.7 ± 1.54,P ＜ 0.01).(3) CD2AP mRNA was reduced in podocyte exposed to high glucose,high Ang-Ⅱ,and mixed environment at least 48 hours (56.09 ± 1.46,67.68 ±2.58,and 54.08 ±2.74,P ＜0.05).The decrease trend of nephrin and CD2AP mRNA was restrained by PKC inhibitor(90.75 ± 1.33,P ＜0.05).(4) After 48 hours and 72 hours,the apoptosis rates of high glucose group,high Ang-Ⅱ group,and mixed group were risen compared to normal group (P ＜ 0.05).The increase of apoptosis rate can be restrained by PKC inhibitor.Conclusions High glucose,and high Ang-Ⅱ can activate the podocytes PKC activity,inhibit the expression of nephrin and CD2AP mRNAs,and induce podocyte apoptosis.PKC signaling pathway plays an important role in the injury mechanism of Ang-Ⅱ and high glucose to mice podocyte.