الملخص
Objective:To investigate the potential function and related mechanism of microRNA-223 (miRNA-223) in the podocyte pyroptosis of hepatitis B virus (HBV)-associated glomerulonephritis induced by HBV X protein (HBx).Methods:HBx-overexpressing lentivirus was transfected into human renal podocytes to mimic the pathogenesis of HBV-GN. Real-time fluorescence quantitative PCR and Western blotting experiments were used to detect the mRNA and protein expression of pyroptosis-related proteins [nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC) and caspase-1], and inflammatory factors (interleukin-1β and interleukin-18), respectively.TUNEL staining and flow cytometry were used to detect the number of pyroptosis cells. Immunofluorescence staining was used to detect the expression of podocytes biomarkers desmin and nephrin; Hoechst 33342 staining was used to observe the morphological and quantitative changes of podocyte nuclei. Enzyme-linked immunosorbent assay was used to measure caspase-1 activity. The dual luciferase reporter gene assay was used to verify the downstream target of miRNA-223. Podocytes were divided into the following nine groups: control group (no special treatment), empty plasmid group (transfected with empty plasmid), HBx overexpression group (transfected with HBx overexpression lentivirus), HBx overexpression+miRNA-223 mimic group (transfected with HBx overexpression lentivirus and miRNA-223 mimic), HBx overexpression+miRNA-223 inhibitor group (transfected with HBx overexpression lentivirus and miRNA-223 inhibitor), HBx overexpression+miRNA-223 mimic+NLRP3 group (transfected with HBx overexpression lentivirus, miRNA-223 mimic and NLRP3 overexpression plasmid), HBx overexpression+miRNA-223 mimic+ NLRP3 siRNA group (transfected with HBx overexpression lentivirus, miRNA-223 mimic and NLRP3 siRNA), HBx overexpression+miRNA-223 inhibitor+NLRP3 group (transfected with HBx overexpression lentivirus, miRNA-223 inhibitor and NLRP3 overexpression plasmid), HBx overexpression+miRNA-223 inhibitor+NLRP3 siRNA group (transfected with HBx overexpression lentivirus, miRNA-223 inhibitor and NLRP3 siRNA).Results:miRNA-223 was down-regulated in HBx overexpression group compared with the control group ( P < 0.05). TUNEL and immunofluorescence staining showed that NLRP3 knockdown attenuated podocyte injury and pyroptosis induced by HBx overexpression ( P < 0.05). Dual luciferase reporter gene assay demonstrated that NLRP3 was one of the downstream targets of miRNA-223. Rescue experiments revealed that NLRP3 overexpression weakened the protective effect of miRNA-223 in podocyte injury ( P < 0.05). The addition of miRNA-223 mimic and NLRP3 siRNA decreased the expression of NLRP3 inflammasome and cytokines, and reduced the number of pyroptosis cells induced by HBx overexpression (all P < 0.05); The addition of miRNA-223 inhibitor and NLRP3 overexpression plasmid significantly increased the expression of NLRP3 inflammasome and cytokines, caspase-1 activity, and the number of pyroptosis cells (all P < 0.05). Conclusion:HBx may promote podocyte pyroptosis of HBV-GN via downregulating miRNA-223 targeting NLRP3 inflammasome, suggesting that miRNA-223 is expected to be a potential target for the treatment of HBV-GN.
الملخص
Objective:To investigate whether hepatitis B virus X protein (HBx) mediates the podocyte injury through reactive oxygen species (ROS) /nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) signaling pathway.Methods:HBx-overexpressing lentivirus was transfected into renal podocytes of mouse to mimic the pathogenesis of hepatitis B virus-associated glomerulonephritis. Podocytes were divided into the following five groups: blank control group (no special treatment), negative control group (transfected with control lentivirus), HBx overexpression group (transfected with HBx overexpression lentivirus), HBx overexpression+NLRP3 siRNA group (transfected with HBx overexpression lentivirus and NLRP3 siRNA), and HBx overexpression+ROS inhibitor group (transfected with HBx overexpression lentivirus and adding ROS inhibitor). The morphological changes of podocytes were observed with electron microscope. The generation of ROS was detected by dichlorodihydrofluorescein diacetate assay (DCFH-DA). Hoechst 33342 staining was used to observe the morphological and quantitative changes of podocyte nuclei. Enzyme-linked immunosorbent assay was used to detect caspase-1 activity, and the levels of lactate dehydrogenase, interleukin (IL)-1β and IL-18. Quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression levels of mRNA and protein of pyroptosis-related protein, such as NLRP3, apoptosis-associated speck-like protein containing card (ASC), caspase-1, IL-1β and IL-18. TUNEL staining and flow cytometer were used to detect the number of pyroptosis cells. Immunofluorescence staining was used to detect the expression levels of desmin and nephrin.Results:After successful infection of podocytes with HBx-overexpressing lentivirus, pyroptosis-related morphological changes in the cells were observed under electron microscope. The level of ROS in the HBx overexpression group was significantly higher compared to the negative control group ( P<0.05). Hoechst 33342 staining revealed condensed nuclei in the HBx overexpression group. TUNEL staining and flow cytometer demonstrated that podocytes underwent increased pyroptosis in the HBx overexpression group. The mRNA and protein expression levels of pyroptosis-related proteins such as NLRP3, ASC, caspase-1, IL-1β and IL-18 were up-regulated upon HBx overexpression (all P<0.05). Caspase-1 enzyme activity, lactate dehydrogenase and desmin expression levels were enhanced after HBx overexpression (all P<0.05). However, NLRP3 knockdown or addition of ROS inhibitors attenuated the pyroptosis and increased expression levels of pyroptosis-related proteins caused by HBx overexpression (all P<0.05). Conclusion:ROS/NLRP3 pathway plays an important role in HBx-induced podocyte pyroptosis.
الملخص
Objective To investigate the diagnostic value and imaging characteristics of MRI in the placenta accreta of patients with retained placenta.Methods Archieves of patients with retained placenta confirmed by clinical pathology were reviewed,with focus on imaging findings of MRI,including location of and signal intensity of placenta attach,hematometra,presence and absence of placenta accreta,signal intensity of retained placenta,shape,margin and border of retained placenta.The imaging characteristics were analysized with blindness and compared between patients with and without placenta accreta.Diagnostic value of MRI and ultrasound for the placenta accreta of patients with retained products of conception was assessed.Results There was no significant difference between the two groups of MRI characteristics except that the edge of the placenta was not clear.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value for the evaluation of placenta accreta by MRI and ultrasound were 93.8% vs 56.3%,90.9% vs 90.9%,92.6%vs 70.4%,0.94 vs 0.9,0.91 vs 0.59,respectively;there were significant differences between MRI and ultrasound for sensitivity, specificity and negative predictive value.Conclusion M RI is substantially better than ultrasound for the diagnosis of placenta accreta. The unclear placenta edge and signs of placental infiltration of the myometrium are the basis for MRI diagnosis of placenta accreta.