Objective:To investigate the protective effect and its mechanism of proscillaridin A (PSD-A) on podocyte injury in lupus nephritis (LN).Methods:Molecular docking and surface plasmon resonance techniques were used to analyze the binding status of PSD-A to signal transducer and activator of transcription 1 (STAT1). The immortalized human podocyte injury model in the lupus group was induced by the serum of systemic lupus erythematosus patients, and the control and PSD-A intervention (2 nmol/L, 4 nmol/L) groups were also set up. Six female 12-week-old C57BL/6 mice were designated as the control group, and 12 female 12-week-old MRL/lpr lupus mice were randomly divided into lupus group and PSD-A intervention group by random number table method. The PSD-A intervention group was intraperitoneally injected with 5 mg/kg PSD-A, once per week for 6 consecutive weeks. While the control group and the lupus group were intraperitoneally injected with the same volume of the solvent without PSD-A. Western blotting and real-time quantitative PCR were employed to detect the relative protein and mRNA expression levels of podocin, STAT1, and interferon-induced protein with tetratricopeptide repeat 1 (IFIT1) in podocytes of each group. Enzyme-linked immunosorbent assay was used to detect the levels of serum anti-double strand DNA antibody and interferon-α in mice. Coomassie brilliant blue was used to detect the urinary protein level. HE, PAS, Masson and PASM staining and transmission electron microscopy were used to observe the pathological changes of renal tissues. Immunohistochemistry was used to examine the protein expression of podocin, STAT1 and IFIT1 in renal tissues.Results:Molecular docking and surface plasmon resonance techniques proved that PSD-A could bind to STAT1 protein and they exhibited a robust binding affinity. The podocyte experiments showed that, compared with the lupus group, the relative expression levels of podocin protein and mRNA in the PSD-A intervention group were upregulated, while the relative expression levels of STAT1 and IFIT1 protein and mRNA were downregulated (all P<0.05). The animal experiments showed that, compared with the lupus group, the serum levels of anti-double strand DNA antibody, interferon-α, and urinary protein in PSD-A intervention group were decreased, the pathological damage of renal tissues was alleviated, and the injury of renal podocytes was reduced. Immunohistochemical staining showed that the relative protein expression levels of STAT1 and IFIT1 of renal tissues in the PSD-A intervention group were lower than those in the lupus group (all P<0.05). Conclusion:PSD-A can play a protective role in podocyte injury in LN, and its mechanism may be related to the inhibition of the STAT1 signaling pathway.

Objective:To investigate the protective effect and its mechanism of proscillaridin A (PSD-A) on podocyte injury in lupus nephritis (LN).Methods:Molecular docking and surface plasmon resonance techniques were used to analyze the binding status of PSD-A to signal transducer and activator of transcription 1 (STAT1). The immortalized human podocyte injury model in the lupus group was induced by the serum of systemic lupus erythematosus patients, and the control and PSD-A intervention (2 nmol/L, 4 nmol/L) groups were also set up. Six female 12-week-old C57BL/6 mice were designated as the control group, and 12 female 12-week-old MRL/lpr lupus mice were randomly divided into lupus group and PSD-A intervention group by random number table method. The PSD-A intervention group was intraperitoneally injected with 5 mg/kg PSD-A, once per week for 6 consecutive weeks. While the control group and the lupus group were intraperitoneally injected with the same volume of the solvent without PSD-A. Western blotting and real-time quantitative PCR were employed to detect the relative protein and mRNA expression levels of podocin, STAT1, and interferon-induced protein with tetratricopeptide repeat 1 (IFIT1) in podocytes of each group. Enzyme-linked immunosorbent assay was used to detect the levels of serum anti-double strand DNA antibody and interferon-α in mice. Coomassie brilliant blue was used to detect the urinary protein level. HE, PAS, Masson and PASM staining and transmission electron microscopy were used to observe the pathological changes of renal tissues. Immunohistochemistry was used to examine the protein expression of podocin, STAT1 and IFIT1 in renal tissues.Results:Molecular docking and surface plasmon resonance techniques proved that PSD-A could bind to STAT1 protein and they exhibited a robust binding affinity. The podocyte experiments showed that, compared with the lupus group, the relative expression levels of podocin protein and mRNA in the PSD-A intervention group were upregulated, while the relative expression levels of STAT1 and IFIT1 protein and mRNA were downregulated (all P<0.05). The animal experiments showed that, compared with the lupus group, the serum levels of anti-double strand DNA antibody, interferon-α, and urinary protein in PSD-A intervention group were decreased, the pathological damage of renal tissues was alleviated, and the injury of renal podocytes was reduced. Immunohistochemical staining showed that the relative protein expression levels of STAT1 and IFIT1 of renal tissues in the PSD-A intervention group were lower than those in the lupus group (all P<0.05). Conclusion:PSD-A can play a protective role in podocyte injury in LN, and its mechanism may be related to the inhibition of the STAT1 signaling pathway.

Objective To investigate the effect of YTH domain family protein 2(YTHDF2)on an-giotensin Ⅱ(Ang Ⅱ)-induced hypertrophy and apoptosis of primary neonatal rat cardiomyocytes.Methods The expression level of YTHDF2 was detected in the primary neonatal rat cardiomyo-cytes with or without Ang Ⅱ stimulation(AngⅡ group and normal group).The cells were divid-ed into blank group(transfected with siRNA+PBS),siYTHDF2 group(transfected with siYTHDF2+PBS),model group(siRNA+Ang Ⅱ)and experimental group(siYTHDF2+Ang Ⅱ)to investi-gate the effects of silencing YTHDF2 on the hypertrophy and apoptosis of cardiomyocytes.West-ern blotting and RT-qPCR were used to detect the expression of YTHDF2 at protein and mRNA levels,and RT-qPCR was employed to measure the mRNA levels of myocardial hypertrophic related genes atrial natriuretic peptide(ANP),brain natriuretic peptide(BNP)and beta-myosin heavy chain(β-MHC),and cardiomyocyte apoptosis related genes Bax and B lymphocytoma 2 gene(Bcl-2).The surface area of cardiomyocytes was observed by α-actin immunofluorescence staining.Cardiomyocyte apoptosis was observed by TUNEL staining,and the binding relationship between YTHDF2 and Bcl-2 was verified by immunoprecipitation.Results The expression of YTHDF2 at protein and mRNA levels were significantly higher in the AngⅡ group than the nor-mal group(1.49±0.03 vs 0.97±0.09,1.50±0.08 vs 1.00±0.07,P＜0.05).Compared with the blank group,the surface area of cardiomyocytes was notably enlarged,apoptotic rate was obvi-ously increased,the mRNA levels of ANP,BNP,β-MHC and Bax were significantly increased,and that of Bcl-2 was remarkably decreased in the model group(P＜0.05).The experimental group obtained decreased surface area and apoptotic rate of cardiomyocytes,lower mRNA levels of ANP,BNP,β-MHC and Bax,and increased mRNA expression of Bcl-2(P＜0.05).Conclusion Silencing YTHDF2 can alleviate Ang Ⅱ-induced hypertrophy and apoptosis in primary neonatal rat cardiomyocyte,and YTHDF2 inhibits the expression of Bcl-2 by binding to it.