Objective To explore effect of EZH2 knockout on podocyte injury and JAK2/STAT3 signaling pathway in mice model with focal segmental glomerulosclerosis(FSGS).

Methods Sixty Cas9 mice were randomly divided into EZH2 knockout group(n=30) and the EZH2 non-knockout group (n=30). Mice in EZH2 knockout group were intravenously injected with recombinant adenovirus (AAV9-sgRNA-EZH2), those in the EZH2 non-knockout group were intravenously injected with phosphate buffered solution (PBS). Mice in the two groups were injected with doxorubicin once through tail vein to establish EZH2 knockout FSGS model and EZH2 non-knockout FSGS model, respectively. The renal tissue pathological changes were observed by hematoxylin and eosin (HE) staining. The nephrin and podocin expressions were observed by double immunofluorescence. Podocyte apoptosis index was detected by TUNEL. The JAK2 and STAT3 protein expressions were detected by western blot method.

Results Compared with mice in the EZH2 non-knockout group, the mice had more serious glomerular pathological changes, widely fused foot processes, significantly thickened glomerular basement membrane, increased mesangial matrix and blocked capillaries. Compared with FSGS mice in the EZH2 non-knockout group, the expressions of nephrin and podocin in podocytes of FSGS mice in the EZH2 knockout group were decreased (P < 0.01). The apoptosis index of podocytic cells in the EZH2 knockout group was (40.94±2.13)%, which was higher than (21.23±3.30)% in the EZH2 non-knockout group (P < 0.01). The protein expression levels of JAK2 and STAT3 in the EZH2 knockout group were (2.67±0.41) and (2.37±0.53) respectively, which were higher than (1.72±0.31) and (1.70±0.48) in the EZH2 non-knockout group (P < 0.01).

Conclusion EZH2 gene knockout may be involved in the activation of JAK2/STAT3 signaling pathway and aggravate renal podocyte injury in FSGS mice.