Hes1 Controls Proliferation and Apoptosis in Chronic Lymphoblastic Leukemia Cells by Modulating PTEN Expression.

Hairy and enhancer of split homolog-1 (HES1), regulated by the Notch, has been reported to play important roles in the immune response and cancers, such as leukemia. In this study, we aim to explore the effect of HES1-mediated Notch1 signaling pathway in chronic lymphocytic leukemia (CLL). Reverse transcription quantitative polymerase chain reaction and Western blot assay were conducted to determine the expression of HES1, Notch1, and PTEN in B lymphocytes of peripheral blood samples of 60 CLL patients. We used lentivirus-mediated overexpression or silencing of HES1 and the Notch1 signaling pathway inhibitor, MW167, to detect the interaction among HES1, Notch1, and PTEN in CLL MEC1 and HG3 cells. MTT assay and flow cytometry were employed for detection of biological behaviors of CLL cells. HES1 and Notch1 showed high expression, but PTEN displayed low expression in B lymphocytes of peripheral blood samples of patients with CLL in association with poor prognosis. HES1 bound to the promoter region of PTEN and reduced PTEN expression. Overexpression of HES1 activated the Notch1 signaling pathway, thus promoting the proliferation of CLL cells, increasing the proportion of cells arrested at the S phase and limiting the apoptosis of CLL cells. Collectively, HES1 can promote activation of the Notch1 signaling pathway to cause PTEN transcription inhibition and the subsequent expression reduction, thereby promoting the proliferation and inhibiting the apoptosis of CLL cells.

Integrated Multichip Analysis Identifies Potential Key Genes in the Pathogenesis of Nonalcoholic Steatohepatitis.

Background: Nonalcoholic steatohepatitis (NASH) is rapidly becoming a major chronic liver disease worldwide. However, little is known concerning the pathogenesis and progression mechanism of NASH. Our aim here is to identify key genes and elucidate their biological function in the progression from hepatic steatosis to NASH. Methods: Gene expression datasets containing NASH patients, hepatic steatosis patients, and healthy subjects were downloaded from the Gene Expression Omnibus database, using the R packages biobase and GEOquery. Differentially expressed genes (DEGs) were identified using the R limma package. Functional annotation and enrichment analysis of DEGs were undertaken using the R package ClusterProfile. Protein-protein interaction (PPI) networks were constructed using the STRING database. Results: Three microarray datasets GSE48452, GSE63067 and GSE89632 were selected. They included 45 NASH patients, 31 hepatic steatosis patients, and 43 healthy subjects. Two up-regulated and 24 down-regulated DEGs were found in both NASH patients vs. healthy controls and in steatosis subjects vs. healthy controls. The most significantly differentially expressed genes were FOSB (P = 3.43×10-15), followed by CYP7A1 (P = 2.87×10-11), and FOS (P = 6.26×10-11). Proximal promoter DNA-binding transcription activator activity, RNA polymerase II-specific (P = 1.30×10-5) was the most significantly enriched functional term in the gene ontology analysis. KEGG pathway enrichment analysis indicated that the MAPK signaling pathway (P = 3.11×10-4) was significantly enriched. Conclusion: This study characterized hub genes of the liver transcriptome, which may contribute functionally to NASH progression from hepatic steatosis.

Butyrate Protects Mice Against Methionine-Choline-Deficient Diet-Induced Non-alcoholic Steatohepatitis by Improving Gut Barrier Function, Attenuating Inflammation and Reducing Endotoxin Levels.

Butyrate exerts protective effects against non-alcoholic steatohepatitis (NASH), but the underlying mechanisms are unclear. We aimed to investigate the role of butyrate-induced gut microbiota and metabolism in NASH development. Sixty-five C57BL/6J mice were divided into four groups (n = 15-17 per group) and were fed either a methionine-choline-sufficient (MCS) diet or methionine-choline-deficient (MCD) diet with or without sodium butyrate (SoB; 0.6 g/kg body weight) supplementation for 6 weeks. Liver injury, systematic inflammation, and gut barrier function were determined. Fecal microbiome and metabolome were analyzed using 16S rRNA deep sequencing and gas chromatography-mass spectrometry (GC-MS). The results showed that butyrate alleviated the MCD diet-induced microbiome dysbiosis, as evidenced by a significantly clustered configuration separate from that of the MCD group and by the depletion of Bilophila and Rikenellaceae and enrichment of promising probiotic genera Akkermansia, Roseburia, Coprococcus, Coprobacillus, Delftia, Sutterella, and Coriobacteriaceae genera. The fecal metabolomic profile was also substantially improved by butyrate; several butyrate-responsive metabolites involved in lipid metabolism and other pathways, such as stearic acid, behenic acid, oleic acid, linoleic acid, squalene, and arachidonic acid, were identified. Correlation analysis of the interaction matrix indicated that the modified gut microbiota and fecal metabolites induced by butyrate were strongly correlated with the alleviation of hepatic injury, fibrosis progression, inflammation, and lipid metabolism and intestinal barrier dysfunction. In conclusion, our results demonstrated that butyrate exerts protective effects against NASH development, and these effects may be driven by the protective gut microbiome and metabolome induced by butyrate. This study thus provides new insights into NASH prevention.

Dynamic alterations in the gut microbiota and metabolome during the development of methionine-choline-deficient diet-induced nonalcoholic steatohepatitis.

AIM: To investigate changes in gut microbiota and metabolism during nonalcoholic steatohepatitis (NASH) development in mice fed a methionine-choline-deficient (MCD) diet. METHODS: Twenty-four male C57BL/6J mice were equally divided into four groups and fed a methionine-choline-sufficient diet for 2 wk (Control 2w group, n = 6) or 4 wk (Control 4w group, n = 6) or the MCD diet for 2 wk (MCD 2w group, n = 6) or 4 wk (MCD 4w group, n = 6). Liver injury, fibrosis, and intestinal barrier function were evaluated after 2 and 4 wk of feeding. The fecal microbiome and metabolome were studied using 16s rRNA deep sequencing and gas chromatography-mass spectrometry. RESULTS: The mice fed the MCD diet presented with simple hepatic steatosis and slight intestinal barrier deterioration after 2 wk. After 4 wk of feeding with the MCD diet, however, the mice developed prominent NASH with liver fibrosis, and the intestinal barrier was more impaired. Compared with the control diet, the MCD diet induced gradual gut microbiota dysbiosis, as evidenced by a marked decrease in the abundance of Alistipes and the (Eubacterium) coprostanoligenes group (P < 0.001 and P < 0.05, respectively) and a significant increase in Ruminococcaceae UCG 014 abundance (P < 0.05) after 2 wk. At 4 wk, the MCD diet significantly reduced the promising probiotic Bifidobacterium levels and markedly promoted Bacteroides abundance (P < 0.05, and P < 0.01, respectively). The fecal metabolomic profile was also substantially altered by the MCD diet: At 2 wk, arachidic acid, hexadecane, palmitic acid, and tetracosane were selected as potential biomarkers that were significantly different in the corresponding control group, and at 4 wk, cholic acid, cholesterol, arachidic acid, tetracosane, and stearic acid were selected. CONCLUSION: The MCD diet induced persistent alterations in the gut microbiota and metabolome.