TRIM25 inhibits HBV replication by promoting HBx degradation and the RIG-I-mediated pgRNA recognition / 中华医学杂志(英文版)

BACKGROUND@#The hepatitis B virus (HBV) vaccine has been efficiently used for decades. However, hepatocellular carcinoma caused by HBV is still prevalent globally. We previously reported that interferon (IFN)-induced tripartite motif-containing 25 (TRIM25) inhibited HBV replication by increasing the IFN expression, and this study aimed to further clarify the anti-HBV mechanism of TRIM25.@*METHODS@#The TRIM25-mediated degradation of hepatitis B virus X (HBx) protein was determined by detecting the expression of HBx in TRIM25-overexpressed or knocked-out HepG2 or HepG2-NTCP cells via Western blotting. Co-immunoprecipitation was performed to confirm the interaction between TRIM25 and HBx, and colocalization of TRIM25 and HBx was identified via immunofluorescence; HBV e-antigen and HBV surface antigen were qualified by using an enzyme-linked immunosorbent assay (ELISA) kit from Kehua Biotech. TRIM25 mRNA, pregenomic RNA (pgRNA), and HBV DNA were detected by quantitative real-time polymerase chain reaction. The retinoic acid-inducible gene I (RIG-I) and pgRNA interaction was verified by RNA-binding protein immunoprecipitation assay.@*RESULTS@#We found that TRIM25 promoted HBx degradation, and confirmed that TRIM25 could enhance the K90-site ubiquitination of HBx as well as promote HBx degradation by the proteasome pathway. Interestingly, apart from the Really Interesting New Gene (RING) domain, the SPRY domain of TRIM25 was also indispensable for HBx degradation. In addition, we found that the expression of TRIM25 increased the recognition of HBV pgRNA by interacting with RIG-I, which further increased the IFN production, and SPRY, but not the RING domain is critical in this process.@*CONCLUSIONS@#The study found that TRIM25 interacted with HBx and promoted HBx-K90-site ubiquitination, which led to HBx degradation. On the other hand, TRIM25 may function as an adaptor, which enhanced the recognition of pgRNA by RIG-I, thereby further promoting IFN production. Our study can contribute to a better understanding of host-virus interaction.

The relationship between hyperuricaemia and clinic pathology of IgA nephropathy / 中华内科杂志

objective To analyze the correlation between the level of serum uric acid and the clinical and pathological features of IgA nephropathy.Methods Totally 148 patients diagnosed as IgA nephropathy by renal biopsy in our hospital from January 2007 to December 2010 were divided into hyperuricaemic group(41 cases)and non-hyperuricaemic group(107 cases)according to the level of serum uric acid.The clinical parameters and renal pathology grade were compared.Results There were significant differences between hyperuricaemic group and non-hyperuricaemic group in the incidences of hypertension(63.4%vs 38.3%),disease duration[(18.90±10.12)months vs(9.46±3.91)months]and body mass index[(22.81±3.60)kg/m2vs(15.32±2.54)kg/m2](all P0.05).The blood urea nitrogen(BUN)[(8.93±4.28)mmol/L vs (5.21±2.18)mmol/L],creatinine(Cr)[(155.96±107.72)μmol/L vs(79.52±40.01)μmol/L],serum triglycerides[(2.11±1.06)mmoVL vs(1.86±1.20)mmol/L]and 24-hour urine protein amount [(4328.16±1434.25)mg/24 h vs(2885.10±1388.15)mg/24 h]were significantly different between the two groups(all P<0.05).The percentage of Lee's grade I+Ⅱin hyperuricaemic group was 12.2%,and IV+V grade was 39.0%,while percentage of Lee's grade I+Ⅱin non-hyperuricaemic group was 25.2%,and IV+V grade was 16.9%(P<0.05).Tubulointerstitial lesions(TIL)gradeⅢ+IV was more in hyperuricaemic group,which was 68.3%,while TIL grade II was more in non-hyperuricaemic group,which was 76.6%.Renal artery damage grade II+Ⅲ was more in hyperuricaemic group.which was 73.2%,while renal artery damage grade 0+1 was more in non-hyperuricaemic group,which was 69.2%.Conclusion The level of serum uric acid was related with 24-hour urine protein amount,blood pressure and kidney function in IgA nephropathy,and Lee's grade,TIL grade and renal artery damage grade were severe in hyperuricaemic group.