Tributyrin alleviates gut microbiota dysbiosis to repair intestinal damage in antibiotic-treated mice.

Tributyrin (TB) is a butyric acid precursor and has a key role in anti-inflammatory and intestinal barrier repair effects by slowly releasing butyric acid. However, its roles in gut microbiota disorder caused by antibiotics remain unclear. Herein, we established an intestinal microbiota disorder model using ceftriaxone sodium via gavage to investigate the effects of different TB doses for restoring gut microbiota and intestinal injury. First, we divided C57BL/6 male mice into two groups: control (NC, n = 8) and experimental (ABx, n = 24) groups, receiving gavage with 0.2 mL normal saline and 400 mg/mL ceftriaxone sodium solution for 7 d (twice a day and the intermediate interval was 6 h), respectively. Then, mice in the ABx group were randomly split into three groups: model (M, 0.2 mL normal saline), low TB group (TL, 0.3 g/kg BW), and high TB group (TH, 3 g/kg BW) for 11 d. We found that TB supplementation alleviated antibiotics-induced weight loss, diarrhea, and intestinal tissue damage. The 16S rRNA sequence analysis showed that TB intervention increased the α diversity of intestinal flora, increased potential short-chain fatty acids (SCFAs)-producing bacteria (such as Muribaculaceae and Bifidobacterium), and inhibited the relative abundance of potentially pathogenic bacteria (such as Bacteroidetes and Enterococcus) compared to the M group. TB supplementation reversed the reduction in SCFAs production in antibiotic-treated mice. Additionally, TB downregulated the levels of serum LPS and zonulin, TNF-α, IL-6, IL-1ß and NLRP3 inflammasome-related factors in intestinal tissue and upregulated tight junction proteins (such as ZO-1 and Occludin) and MUC2. Overall, the adjustment ability of low-dose TB to the above indexes was stronger than high-dose TB. In conclusion, TB can restore the dysbiosis of gut microbiota, increase SCFAs, suppress inflammation, and ameliorate antibiotic-induced intestinal damage, indicating that TB might be a potential gut microbiota modulator.

The Combination of Inositol Hexaphosphate and Inositol Inhibits Metastasis of Colorectal Cancer Cells by Upregulating Claudin 7.

Inositol hexaphosphate (IP6), a widely found natural bioactive substance in grains, effectively inhibits the progression of colorectal cancer (CRC) when used in combination with inositol (INS). We previously showed that supplementation of IP6 and INS upregulated the claudin 7 gene in orthotropic CRC xenografts in mice. The aim of this study was to elucidate the role of claudin 7 in the inhibition of CRC metastasis by IP6 and INS, and explore the underlying mechanisms. We found that IP6, INS and their combination inhibited the epithelial-mesenchymal transition (EMT) of colon cancer cell lines (SW480 and SW620), as indicated by upregulation of claudin 7 and E-cadherin, and downregulation of N-cadherin. The effect of IP6 and INS was stronger compared to either agent alone (combination index < 1). Furthermore, the silencing of the claudin 7 gene diminished the anti-metastatic effects of IP6 and INS on SW480 and SW620 cells. Consistent with in vitro findings, the combination of IP6 and INS suppressed CRC xenograft growth in a mouse model, which was neutralized by claudin 7. Taken together, the combination of IP6 and INS can inhibit CRC metastasis by blocking EMT of tumor cells through upregulation of claudin 7.

Discovery, design and synthesis of 6H-anthra[1,9-cd]isoxazol-6-one scaffold as G9a inhibitor through a combination of shape-based virtual screening and structure-based molecular modification.

Protein lysine methyltransferase G9a is widely considered as an appealing antineoplastic target. Herein we present an integrated workflow combining shape-based virtual screening and structure-based molecular modification for the identification of novel G9a inhibitors. The shape-based similarity screening through ROCS overlay on the basis of the structure of UNC0638 was performed to identify CPUY074001 contained a 6H-anthra[1,9-cd]isoxazol-6-one scaffold as a hit. Analysis of the binding mode of CPUY074001 with G9a and 3D-QSAR results, two series compounds were designed and synthesized. The derivatives were confirmed to be active by in vitro assay and the SAR was explored by docking stimulations. Besides, several analogues showed acceptable anti-proliferative effects against several cancer cell lines. Among them, CPUY074020 displayed potent dual G9a inhibitory activity and anti-proliferative activity. Furthermore, CPUY074020 induced cell apoptosis in a dose-dependent manner and displayed a significant decrease in dimethylation of H3K9. Simultaneously, CPUY074020 showed reasonable in vivo PK properties. Altogether, our workflow supplied a high efficient strategy in the identification of novel G9a inhibitors. Compounds reported here can serve as promising leads for further study.