Molecular characterization of m6A RNA methylation regulators with features of immune dysregulation in IgA nephropathy.

The role of RNA N6-methyladenosine (m6A) modification in immunity is being elucidated. This study aimed to explore the potential association between m6A regulators and the immune microenvironment in IgA nephropathy (IgAN). The expression profiles of 24 m6A regulators in 107 IgAN patients were obtained from the Gene Expression Omnibus (GEO) database. The least absolute shrinkage and selection operator (LASSO) regression and logistic regression analysis were utilized to construct a model for distinguishing IgAN from control samples. Based on the expression levels of m6A regulators, unsupervised clustering was used to identify m6A-induced molecular clusters in IgAN. Gene set enrichment analysis (GSEA) and immunocyte infiltration among different clusters were examined. The gene modules with the highest correlation for each of the three clusters were identified by weighted gene co-expression network analysis (WGCNA). A model containing 10 m6A regulators was developed using LASSO and logistic regression analyses. Three molecular clusters were determined using consensus clustering of 24 m6A regulators. A decrease in the expression level of YTHDF2 in IgAN samples was significantly negatively correlated with an increase in resting natural killer (NK) cell infiltration and was positively correlated with the abundance of M2 macrophage infiltration. The risk scores calculated by the nomogram were significantly higher for cluster-3, and the expression levels of m6A regulators in this cluster were generally low. Immunocyte infiltration and pathway enrichment results for cluster-3 differed significantly from those for the other two clusters. Finally, the expression of YTHDF2 was significantly decreased in IgAN based on immunohistochemical staining. This study demonstrated that m6A methylation regulators play a significant role in the regulation of the immune microenvironment in IgAN. Based on m6A regulator expression patterns, IgAN can be classified into multiple subtypes, which might provide additional insights into novel therapeutic methods for IgAN.

Targeting P2RX1 alleviates renal ischemia/reperfusion injury by preserving mitochondrial dynamics.

Renal ischemia/reperfusion injury (IRI) is the major cause of acute kidney injury. However, mechanisms underlying the sudden loss in kidney function and tissue injury remain to be fully elucidated. Here, we performed RNA sequencing to systematically compare the transcriptome differences between IR injured kidneys and sham kidneys. We observed that mitochondrial dynamics was destructed in renal IRI. Expression of mitochondrial fusion-associated genes was reduced, whereas expression of mitochondrial fission-related genes was increased in renal IRI, and these findings were further confirmed by mitochondrial morphological observations. By screening 19 purinergic receptors, we noticed that P2RX1 expression was markedly upregulated in renal IRI. RNA sequencing and mitochondrial morphological observations revealed that mitochondrial dynamics was preserved in P2RX1 genetic knockout (P2rx1-/-) mice. Neutrophil extracellular traps (NETs) were reported to be essential for tissue injury in renal IRI, but the detailed mechanism remained unclear. In the present study, we found that P2RX1 favored the formation of neutrophil extracellular traps (NETs) in IRI, and NETs was essential for the impairment of mitochondrial dynamics. Mechanistically, P2RX1-involved metabolic interaction between platelets and neutrophils supported NETs formation. Activation of P2RX1 promoted platelets ATP release, which subsequently contributed to neutrophil glycolytic metabolism and NETs generation.

A redox probe screens MTHFD1 as a determinant of gemcitabine chemoresistance in cholangiocarcinoma.

Cholangiocarcinoma (CCA) is a type of solid tumor derived from the bile duct epithelium that features universal gemcitabine resistance. Here, we utilized a gene-encoded ROS biosensor probe (HyPer3 probe) to sort subpopulations with different redox statuses from CCA cells. The isolated HyPer-low subpopulation CCA cells, which exhibited relatively lower cellular ROS levels, exhibited higher chemoresistance to gemcitabine than HyPer-high subpopulation CCA cells in vitro and in vivo. Mechanistically, increased expression of MTHFD1 was found in HyPer-low cells. Knocking down MTHFD1 in HyPer-low cells enhanced cellular ROS and restored sensitivity to gemcitabine. Furthermore, the MTHFD1 inhibitor antifolate compound methotrexate (MTX) increased cellular ROS, and combining gemcitabine with MTX effectively suppressed cholangiocarcinoma cell growth. In summary, the MTHFD1 level mediated the heterogeneous cellular redox status in CCA, which resulted in chemoresistance to gemcitabine. Our data suggest a novel strategy for CCA chemotherapy.

Duodenal perforations secondary to a migrated biliary plastic stent successfully treated by endoscope: case-report and review of the literature.

BACKGROUND: Endoscopic retrograde biliary drainage (ERBD) is the most frequently performed procedure for treating benign or malignant biliary obstruction. Although duodenal perforations secondary to the biliary plastic stent are quite rare, they can be life-threatening. The treatment strategies for such perforations are diverse and continue to be debated. CASE PRESENTATION: We report three cases of duodenal perforation due to the migration of biliary plastic stents that were successfully managed using an endoscope. The three patients were admitted on complaints of abdominal pain after they underwent ERBD. Abdominal computerized tomography (CT) revealed migration of the biliary plastic stents and perforation of the duodenum. Endoscopy was immediately performed, and perforation was confirmed. All migrated stents were successfully extracted endoscopically by using snares. In two of the three cases, the duodenal defects were successfully closed with haemostatic clips after stent retrieval, and subsequently, endoscopic nasobiliary drainage tubes were inserted. After the endoscopy and medical treatment, all three patients recovered completely. CONCLUSIONS: Duodenal perforations due to the migration of biliary stents are rare, and the treatment strategies remain controversial. Our cases and cases in the literature demonstrate that abdominal CT is the preferred method of examination for such perforations, and endoscopic management is appropriate as a first-line treatment approach.

Feasibility and safety of single-incision laparoscopic cholecystectomy versus conventional laparoscopic cholecystectomy in an ambulatory setting.

BACKGROUND: Single-incision laparoscopic surgery has emerged as an alternative to conventional laparoscopic cholecystectomy (LC) in the clinical setting. Limited information is available on the possibility of performing single-incision laparoscopic surgery as an ambulatory procedure. This study aimed to determine the feasibility and safety of single-incision laparoscopic cholecystectomy (SILC) versus conventional LC in an ambulatory setting. METHODS: Ninety-one patients were randomized to SILC (n = 49) or LC (n = 42). The success rate, operative duration, blood loss, hospital stay, gallbladder perforation, drainage, delayed discharge, readmission, total cost, complications, pain score, vomiting, and cosmetic satisfaction of the two groups were then compared. RESULTS: There were significant differences in the operative time (46.89 ±â€¯10.03 min in SILC vs. 37.24 ±â€¯10.23 min in LC; P < 0.001). As compared with LC, SILC was associated with lower total costs (8012.28 ±â€¯752.67 RMB vs. 10258.91 ± 1087.63 RMB; P < 0.001) and better cosmetic satisfaction (4.94 ± 0.24 vs. 4.74 ± 0.54; P = 0.031). There were no significant differences between-group in terms of general data, success rate, blood loss, hospital stay, gallbladder perforation, drainage, delayed discharge, readmission, complications, pain score, and vomiting (P > 0.05). CONCLUSIONS: Ambulatory SILC is safe and feasible for selected patients. The advantages of SILC as compared with LC are improved cosmetic satisfaction and lower total costs.

9-cis-retinoic acid elevates MRP3 expression by inhibiting sumoylation of RXRα to alleviate cholestatic liver injury.

AIMS: Vitamin A and its metabolites has been found to be protective against cholestatic liver injury, but the exact underlying mechanisms involved in cholestatic liver injury remain unclear. The objective of this study was to determine the function and mechanisms of 9-cis-retinoic acid, the metabolite of vitamin A, in cholestatic liver injury. METHODS: The bile duct ligated (BDL) mice were treated with 9-cis-retinoic acid by intravenous injection through the tail for 10 days. The liver function and histology were assessed in the matched group and experimental group. The expression of MRP3 in liver tissue was tested by qRT-PCR, Western blotting, and IHC. Effect of RXRα sumoylation on MRP3 expression was investigated at a cellular level. Influence of 9-cis-retinoic acid on RXRα sumoylation was also tested in cells. RESULTS: Our findings showed that 9-cis-retinoic acid significantly decreases the serum ALT and AST level, alleviates hepatic necrosis of the BDL-mice. We also identified MRP3, an important protective hepatobiliary transporter in cholestasis, was elevated by 9-cis-retinoic acid in vivo and in vitro. 9-cis-retinoic acid weakened the sumoylation of RXRα, which promotes the cytoplasmic location of RXRα and lightens the interaction of RXRα and RARα. Inhibition of RXRα and RARα interaction increased MRP3 expression. CONCLUSIONS: 9-cis-retinoic acid alleviates cholestatic liver injury by elevating MRP3 expression through its mechanism of inhibiting sumoylation of RXRα.

Hem-o-lok Clips Migration: An Easily Neglected Complication after Laparoscopic Biliary Surgery.

Clip migration into the common bile duct (CBD) is a rare but well-established phenomenon of laparoscopic biliary surgery. The mechanism and exact incidence of clip migration are both poorly understood. Clip migration into the common bile duct can cause recurrent cholangitis and serve as a nidus for stone formation. We present a case, a 54-year-old woman, of clip-induced cholangitis resulting from surgical clip migration 12 months after laparoscopic cholecystectomy and laparoscopic common bile duct exploration (LC+LCBDE) with primary closure.