Mitochondria-targeted reactive oxygen species blockor SS-31 blocks hepatic stellate cell activation and alleviates hepatic fibrosis by regulating NLRP3 inflammasomes.

This study aimed to elucidate the effect of mitochondria-targeted reactive oxygen species (ROS) blockor SS-31 on hepatic stellate cells (HSC) activation during liver fibrosis. TGF-ß1 was employed to induce HSC activation, while MitoSOX Red was utilized to assess the presence of mitochondrial ROS. The mitochondrial membrane potential (MMP) was measured using the JC-1 probe, and the ATP level was determined using a specific kit. The proliferation of HSCs was assessed using CCK-8 and colony formation assays, whereas flow cytometry was employed to detect HSC apoptosis. Fibrotic markers (COL1A1 and α-SMA) and NLRP3 inflammasome components (NLRP3, caspase-1, and ASC) were analyzed via Western blotting. Liver fibrosis was induced in mice using CCl4, and subsequently, histopathological changes were observed through HE staining and Masson staining. In TGF-ß1-activated HSCs, mitochondrial ROS expression increased, MMP and ATP content decreased, indicating mitochondrial damage. After TGF-ß1 induction, HSC proliferation increased, apoptosis decreased, and COL1A1, α-SMA, and NLRP3 inflammasome protein expression increased. After SS-31 treatment, mitochondrial ROS expression decreased, MMP recovered, ATP level increased, HSC proliferation decreased, apoptosis increased, and the expressions of COL1A1, α-SMA, and NLRP3 inflammasome decreased. NLRP3 blockor MCC950 treatment blocked HSC activation. CCL4-induced liver fibrosis mice had inflammatory cell infiltration and significant collagen fiber deposition in the liver. After SS-31 treatment, liver inflammation and collagen deposition were significantly reduced. SS-31, as a mitochondria-targeted ROS blockor, can block HSC activation by regulating the NLRP3 inflammasome, thereby alleviating liver fibrosis.

APOL1 Induces Pyroptosis of Fibroblasts Through NLRP3/Caspase-1/GSDMD Signaling Pathway in Ulcerative Colitis.

Background: Pyroptosis is a form of proinfammatory gasdermin-mediated programmed cell death. Abnormal infammation in the intestine is a critical risk factor for Ulcerative colitis (UC). However, at present, it is not clear whether pyroptosis of colonic fibroblasts is involved in the pathogenesis and progression of UC. Methods: In this study, key genes associated with UC were identified by bioinformatics analysis. Datasets were downloaded from the Gene Expression Omnibus (GEO) database (GSE193677). The differentially expressed genes were analyzed, and the hub genes were screened by weighted gene co-expression network analysis (WGCNA) and differentially expressed genes. We also downloaded the dataset from GEO for single-cell RNA sequencing (GSE231993). The expression of key genes was verified by immunohistochemistry, immunofluorescence and Western blot, and the specific pathways of key genes inducing pyroptosis in cell lines were explored. Results: The results of bioinformatics analysis showed that the expression of APOL1 and CXCL1 in UC tissues was significantly higher than that in normal tissues. The results of single-cell analysis showed that the two genes were co-localized to fibroblasts. These results were consistent with the results of immunohistochemistry and immunofluorescence colocalization in human intestinal mucosa specimens. Furthermore, APOL1 overexpression induced NLRP3-caspase1-GSDMD-mediated pyroptosis of fibroblasts, which was confirmed by Western blot. Conclusion: APOL1 induces pyroptosis of fibroblasts mediated by NLRP3-Caspase1-GSDMD signaling pathway and promote the release of chemokines CXCL1. Fibroblasts may play a crucial role in the pathogenesis and progression of UC.

Effects of long non-coding RNA TUG1 on the proliferation and apoptosis of gastric cancerAGS cells / 中国肿瘤生物治疗杂志

@#Objective: To investigate the expression of lncRNA TUG1 (long non-coding RNA taurine up-regulated gene 1) in gastric cancer and its effect on the proliferation and apoptosis of gastric cancer cells. Methods: Surgically resected gastric cancer tissues and corresponding distal normal tissues (>5 cm away from the margin of tumor) of 40 gastric cancer patients from March 2016 to December 2017 at Ganzhou People's Hospital of Jiangxi Province were collected, and qPCR was used to examine the expression of lncRNA TUG1.AGS gastric cancer cells were transfected with lncRNATUG1 over-expression plasmids and siRNAs, and the effects of lncRNA TUG1 on cell proliferation and apoptosis were assessed by CCK-8, qPCR and Flow cytometry. Results: lncRNATUG1 expression was significantly increased in gastric cancer tissues as compared to normal tissues; and it was not correlated with gender, age, tumor size, infiltration depth of tumor, lymph node-metastasis, tumor differentiation and TNM staging. TUG1 over-expression significantly suppressed the expressions of CDKN1A, BAX and Caspase-3 in AGS gastric cancer cells, and decreased G1 phase proportion and apoptosis rate, but increased S phase proportion and cell viability; in contrast, TUG1 siRNA transfection significantly promoted the expressions of CDKN1A, BAX and Caspase-3, and increased G1 phase proportion and apoptosis rate, but decreased S phase proportion and cell viability. Conclusion: Up-regulated lncRNATUG1 promotes proliferation and inhibits apoptosis of gastric cancer cells.