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 groupsnormal 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.