Protective effect of the "food-microorganism-SCFAs" axis on colorectal cancer: from basic research to practical application.

BACKGROUND: Recent studies have shown that the short-chain fatty acids (SCFAs) produced by the gut microbiota play a positive role in the development of colorectal cancer (CRC). AIMS: This study aims to elucidate the "food-microorganism-SCFAs" axis and to provide guidance for prevention and intervention in CRC. METHODS: The PubMed, Embase and Cochrane databases were searched from their inceptions to August 2018, and 75 articles and 25 conference abstracts were included and analysed after identification and screening. RESULTS: The concentrations of SCFAs in CRC patients and individuals with a high risk of CRC were higher than those in healthy individuals. The protective mechanism of SCFAs against CRC has been described in three aspects: epigenetics, immunology and molecular signalling pathways. Many food and plant extracts that were fermented by microorganisms produced SCFAs that play positive roles with preventive and therapeutic effects on CRC. The "food-microorganism-SCFAs" axis was constructed by summarizing the pertinent literature. CONCLUSIONS: This study provides insight into the basic research and practical application of SCFAs by assessing the protective effect of SCFAs on CRC.

Rosiglitazone and ATRA on gastric cancer SGC7901 cell line proliferation in vitro / 中国医师杂志

Objective To investigate the influence of PPARγ excitomotor RSG and ATRA on gastric cancer SGC7901 cell line proliferation in vitro and its potential mechanism study.Methods Human gastric cancer SGC7901 cell line was cultured in vitro.Experiment samples were divided to blank group,10μmol/L ATRA group, 12.5μmol/L RSG group, 25μmol/L RSG group, 10μmol/L ATRA + 25μmol/L RSG group.Proliferation inhibitory effect was determined by MTI assay.Flow cytometry was used to detect cell cycle, H.E stain was used to observed micrography alteration.Expression of PPARγ protein in gastric cancer cells were measured by immunohistochemistry.PPARγ mRNA in gastric cancer cells were measured by RT-PCR.Results ATAR at concentration 10μmol/L, RSG at 12.5 μmol/L and RSG at 25 μmol/L could inhibit the proliferation of SGC7901 cells in a dose-and time-dependent, and when both agents were combined for 72h, growth inhibition ratio was (29.73 ± 0.69) %.Flow cytometry analysis revealed a cell cycle arrest at G1 and S phase, and when both agents combined, S% was (12.87 ± 0.35 )%, cell micrography tended to be normal when both agents combined.Up-regulation of PPARγ protein and PPARγ mRNA expressions were also observed, those effects were enhanced when both agents combined, and grey scale ratio was 0.646.Conclusion The ATRA and RSG could significantly induced growth inhibition of human gastric cancer SGC7901 cell, which may be associated with cell cycle arrest and inducing differentiation, activation of PPARγ protein and PPARγ mRNA expression.Synergistic effect could be caused by the combined use of the two agents.

Preparation and in vitro antioxidative activity of acetylated fucoidan extracted from Laminaria japonica / 中国海洋药物

Objective To explore the optimum method for preparation of acetylated fucoidan extracted from Laminaria japonica,and test the antioxidative activity of acetylated fucoidans prepared under different conditions in vitro.Methods Using acetic anhydride as acetylated reagent,N-Bromosuccinimide(NBS) as catalyst,the effects of reaction time,temperature and volume of acetylated reagent were tested by the orthogonal design method.The antioxidative activity of the prepared acetylated fucoidans in vitro was determined,including scavenging activity against superoxide,hydroxyl and DPPH radical and reducing power.Results Volume of acetylated reagent and reaction temperature were the significant factors(P