Epigallocatechin gallate suppresses mitotic clonal expansion and adipogenic differentiation of preadipocytes through impeding JAK2/STAT3-mediated transcriptional cascades.

BACKGROUND: Mitotic clonal expansion (MCE) is a prerequisite for preadipocyte differentiation and adipogenesis. Epigallocatechin gallate (EGCG) has been shown to inhibit preadipocyte differentiation. However, the exact molecular mechanisms are still elusive. PURPOSE: This study investigated whether EGCG could inhibit adipogenesis and lipid accumulation by regulating the cell cycle in the MCE phase of adipogenesis and its underlying molecular mechanisms. METHOD: 3T3-L1 preadipocytes were induced to differentiate by a differentiation cocktail (DMI) and were treated with EGCG (25-100 µM) for 9, 18, and 24 h to examine the effect on MCE, or eight days to examine the effect on terminal differentiation. C57BL/6 mice were fed a high-fat diet (HFD) for three months to induce obesity and were given EGCG (50 or 100 mg/kg) daily by gavage. RESULTS: We showed that EGCG significantly inhibited terminal adipogenesis and lipid accumulation in 3T3-L1 cells and decreased expressions of PPARγ, C/EBPα, and FASN. Notably, at the MCE phase, EGCG regulated the cell cycle in sequential order, induced G0/G1 arrest at 18 h, and inhibited the G2/M phase at 24 h upon DMI treatment. Meanwhile, EGCG regulated the expressions of cell cycle regulators (cyclin D1, cyclin E1, CDK4, CDK6, cyclin B1, cyclin B2, p16, and p27), and decreased C/EBPß, PPARγ, and C/EBPα expressions at MCE. Mechanistic studies using STAT3 agonist Colivelin and antagonist C188-9 revealed that EGCG-induced cell cycle arrest in the MCE phase and terminal adipocyte differentiation was mediated by the inhibition of JAK2/STAT3 signaling cascades and STAT3 (Tyr705) nuclear translocation. Furthermore, EGCG significantly protected mice from HFD-induced obesity, reduced body weight and lipid accumulations in adipose tissues, reduced hyperlipidemia and leptin levels, and improved glucose intolerance and insulin sensitivity. Moreover, RNA sequencing (RNA-seq) analysis showed that the cell cycle changes in epididymal white adipose tissue (eWAT) were significantly enriched upon EGCG treatment. We further verified that EGCG treatment significantly reduced expressions of adipogenic factors, cell cycle regulators, and p-STAT3 in eWAT. CONCLUSION: EGCG inhibits MCE, resulting in the inhibition of early and terminal adipocyte differentiation and lipid accumulation, which were mediated by inhibiting p-STAT3 nucleus translocation and activation.

Ganoderma lucidum polysaccharide inhibits HSC activation and liver fibrosis via targeting inflammation, apoptosis, cell cycle, and ECM-receptor interaction mediated by TGF-ß/Smad signaling.

BACKGROUND: Ganoderma lucidum polysaccharide (GLP) has many biological properties, however, the anti-fibrosis effect of GLP is unknown at present. PURPOSE: This study aimed to examine the anti-fibrogenic effect of GLP and its underlying molecular mechanisms in vivo and in vitro. STUDY DESIGN: Both CCl4-induced mouse and TGF-ß1-induced HSC-T6 cellular models of fibrosis were established to examine the anti-fibrogenic effect of a water-soluble GLP (25 kDa) extracted from the sporoderm-removed spores of G. lucidum.. METHOD: Serum markers of liver injury, histology and fibrosis of liver tissues, and collagen formation were examined using an automatic biochemical analyzer, H&E staining, Sirius red staining, immunohistochemistry, immunofluorescence, ELISA, Western blotting, and qRT-PCR. RNA-sequencing, enrichment pathway analysis, Western blotting, qRT-PCR, and flow cytometry were employed to identify the potential molecular targets and signaling pathways that are responsible for the anti-fibrotic effect of GLP. RESULTS: We showed that GLP (150 and 300 mg/kg) significantly inhibited hepatic fibrogenesis and inflammation in CCl4-treated mice as mediated by the TLR4/NF-κB/MyD88 signaling pathway. We further demonstrated that GLP significantly inhibited hepatic stellate cell (HSCs) activation in mice and in TGF-ß1-induced HSC-T6 cells as manifested by reduced collagen I and a-SMA expressions. RNA-sequencing uncovered inflammation, apoptosis, cell cycle, ECM-receptor interaction, TLR4/NF-κB, and TGF-ß/Smad signalings as major pathways suppressed by GLP administration. Further studies demonstrated that GLP elicits anti-fibrotic actions that are associated with a novel dual effect on apoptosis in vivo (inhibit) or in vitro (promote), suppression of cell cycle in vivo, induction of S phase arrest in vitro, and attenuation of ECM-receptor interaction-associated molecule expressions including integrins ITGA6 and ITGA8. Furthermore, GLP significantly inhibited the TGF-ß/Smad signaling in mice, and reduced TGF-ß1 or its agonist SRI-011381-induced Smad2 and Smad3 phosphorylations, but increased Samd7 expression in HSC-T6 cells. CONCLUSION: This study provides the first evidence that GLP could be a promising dietary strategy for treating liver fibrosis, which protects against liver fibrosis and HSC activation through targeting inflammation, apoptosis, cell cycle, and ECM-receptor interactions that are mediated by TGF-ß/Smad signaling.

Gut Bacterial Diversity and Community Structure of Spodoptera exigua (Lepidoptera: Noctuidae) in the Welsh Onion-producing Areas of North China.

Gut microbiota play an important role in digestion, development, nutritional metabolism, and detoxification in insects. However, scant information exists on the gut bacterial variation, composition, and community structure of the beet armyworm, Spodoptera exigua (Hübner), and how its gut microbiota has adapted to different geographical environments. Using 16S rRNA high-throughput sequencing technology, we detected 3,837,408 high-quality reads and 1,457 operational taxonomic units (OTUs) in 47 gut samples of S. exigua collected from ten sites in northern China. Overall, we identified 697 bacterial genera from 30 phyla, among which Proteobacteria and Firmicutes were the most dominant phyla. Gut bacterial alpha-diversity metrics revealed significant differences among these populations. We detected the highest alpha bacterial diversity in Xinming, northern Liaoning Province, and the lowest bacterial diversity in Zhangwu, western Liaoning Province. Beta diversity indicated that the gut microbial community structure of S. exigua in Liaoning Province was significantly different from that of other populations. There was a similar microbial community structure among populations in the adjacent province, suggesting that the environment influences bacterial succession in this pest. Finally, PICRUSt analysis demonstrated that microbial functions closely associated with the gut microbiomes mainly included membrane transport, carbohydrate metabolism and replication, and amino acid metabolism.

Qizhen capsule inhibits colorectal cancer by inducing NAG-1/GDF15 expression that mediated via MAPK/ERK activation.

ETHNOPHARMACOLOGICAL RELEVANCE: Qizhen capsule (QZC) is a traditional Chinese medicine (TCM) preparation that has been widely used in clinical practice and exerts promising therapeutic effects against breast, lung, and gastric cancers. However, studies have not reported whether QZC inhibits colorectal cancer (CRC) development and progression. Meanwhile, the underlying molecular mechanisms of its anticancer activity have not been studied. AIM OF THE STUDY: To investigate the anticancer effects of QZC on CRC and the possible underlying molecular mechanisms of QZC in vitro and in vivo. MATERIALS AND METHODS: The MTT assay and flow cytometry were used to determine the viability and apoptosis of HCT116 and HT-29 cancer cells. A xenograft nude mouse model was used to study the antitumor effects of QZC in vivo. Western blotting was performed to determine the expression of key proteins responsible for the molecular mechanisms elicited by QZC. Immunofluorescence staining was performed to detect the expression of nonsteroidal anti-inflammatory drug (NSAID)-activated gene-1 or growth differentiation factor-15 (NAG-1/GDF15). Small interfering RNAs (siRNAs) were used to silence NAG-1/GDF15 in cells. RESULTS: In this study, QZC significantly reduced the viability of HCT116 and HT-29 cells and induced apoptosis in dose- and time-dependent manners, but displayed much less toxicity toward normal cells. QZC-induced apoptosis in HCT116 cells was accompanied by the deregulation of the expression of the Bcl-2, Bax, PARP, caspase-3, and caspase-9 proteins. Furthermore, QZC induced NAG-1/GDF15 expression in HCT116 cells, while silencing of NAG-1/GDF15 attenuated QZC-induced apoptosis and cell death. Next, QZC increased the phosphorylation of mTOR, AMPK, p38, and MAPK/ERK in HCT116 cells. We then demonstrated that QZC-induced apoptosis and NAG-1/GDF15 upregulation were mediated by MAPK/ERK activation. Moreover, QZC significantly inhibited HCT116 xenograft tumor growth in nude mice, which was accompanied by NAG/GDF15 upregulation and MAPK/ERK activation. QZC also prevented 5-FU-induced weight loss or cachexia in tumor-bearing mice. The expression of Ki67 and PCNA was suppressed, while cleaved caspase-3 level and TUNEL staining were increased in the tumor sections from QZC-treated mice compared to the control. CONCLUSION: QZC is a novel anticancer agent for CRC that targets NAG-1/GDF15 via the MAPK/ERK signaling pathway.

[Effect of traditional Chinese medicine in inhibiting obesity and inflammatory diseases by regulating gut microbiota].

Traditional Chinese medicine(TCM) has been increasingly used in the prevention and treatment of obesity and obesity-related diseases. However, its mechanism of action is not yet clear. In recent years, with the development of high-throughput sequencing technology, scientific researches have found that the disorder of gut microbiota is associated with obesity and other diseases. Furthermore, it has been found that TCM can improve the structure of gut microbiota by increasing probiotics and reducing pathogens, which play an importent role in preventing the development and progression of obesity and other diseases. This article first explores the possible association between intestinal microbiota and obesity. Then, it reviews the traditional Chinese medicine and its role in regulating intestinal microbiota for the prevention and treatment of diseases, including obesity and inflammation, insulin resistance, type 2 diabetes, non-alcoholic fatty liver disease, inflammatory bowel disease and other diseases, in theexpectation of new strategies and research direction for treating obesity and relevant diseases, and providing important guidance for further studies in this field in the future.

Anticarcinogenic effects of water extract of sporoderm-broken spores of Ganoderma lucidum on colorectal cancer in vitro and in vivo.

Ganoderma lucidum (G. lucidum) polysaccharides (GLPs) have been used as traditional Chinese medicine for cancer prevention for many years. However, the mechanism by which GLP exerts its chemopreventive activities remains elusive. In addition, it is unclear whether sporoderm-broken spores of G. lucidum water extract (BSGLWE), which contains mainly GLPs, has anticancer effects on colorectal cancer. The present study investigated the anticancer effects and potential mechanisms of BSGLWE on colorectal cancer in vivo and in vitro. Our results showed that BSGLWE significantly inhibited colorectal cancer HCT116 cell viability in a time- and dose-dependent manner. Flow cytometry analysis indicated that BSGLWE disrupted cell cycle progression at G2/M phase via downregulation of cyclin B1 and cyclin A2, and upregulation of P21 at mRNA levels. Moreover, BSGLWE induced apoptosis by decreasing Bcl-2 and survivin at mRNA levels, and reduced Bcl-2, PARP, pro-caspase-3 and pro-caspase-9 at protein levels. Furthermore, BSGLWE suppressed tumor growth in vivo by regulating the expression of genes and proteins associated with cell cycle and apoptosis, which was further confirmed by a reduction of Ki67, PCNA, and Bcl-2 expression as determined by immunohistochemistry staining. NSAID activated gene-1 (NAG-1), a pro-apoptotic gene, was significantly upregulated in vivo and in vitro upon BSGLWE treatment at both mRNA and protein levels. In addition, the relative amounts of secreted NAG-1 in cell culture medium or serum of nude mice were all upregulated upon BSGLWE treatments, suggesting a role of NAG-1 in BSGLWE-induced anticolorectal cancer activity. This is the first study to show that BSGLWE inhibits colorectal cancer carcinogenesis through regulating genes responsible for cell proliferation, cell cycle and apoptosis cascades. These findings indicate that BSGLWE possesses chemopreventive potential in colorectal cancer which may serve as a promising anticancer agent for clinical applications.

Chemopreventive and bioenergetic signaling effects of PDK1/Akt pathway inhibition in a transgenic mouse model of prostate cancer.

The phosphoinositide-dependent kinase 1 (PDK1)/Akt pathway is an important regulator of multiple biological processes including cell growth, survival, and glucose metabolism. In light of the mechanistic link between Akt signaling and prostate tumorigenesis, we evaluated the chemopreventive relevance of inhibiting this pathway in the transgenic adenocarcinoma of the model prostate (TRAMP) mouse with OSU03012, a celecoxib-derived, but COX-2-inactive, PDK1 inhibitor. Beginning at ten weeks of age when prostatic intraepithelial neoplasia (PIN) lesions are well developed, TRAMP mice received OSU03012 via daily oral gavage for 8 weeks. The drug treatment significantly decreased the weight of all 4 prostate lobes as well as the grade of epithelial proliferation in the dorsal and lateral lobes compared to vehicle-treated control mice. The incidences of carcinoma and metastasis were decreased, although not to statistically significant levels. Treated mice lost body fat and failed to gain weight independent of food intake. This change and periportal hepatocellular atrophy can be linked to sustained PDK1 inhibition through downstream inactivation of glycogen synthase. Centrilobular hepatocellular hypertrophy and necrosis of Type II skeletal myofibers were also compound-related effects. We conclude that targeting of the PDK1/Akt pathway has chemopreventive relevance in prostate cancer and causes other in vivo effects mediated in part by an alteration of bioenergetic signaling.