ABSTRACT
OBJECTIVE To study the effect and potential mechanism of eriodictyol on non-alcoholic fatty liver disease （NAFLD）. METHODS Sixteen C57BL/6J mice were randomly divided into control group， NAFLD model group， and eriodictyol low-dose and high-dose groups （50， 100 mg/kg）， with 4 mice in each group. Except for control group， the other groups were fed with high fat diet to induce NAFLD model. After four weeks of preprocessing， they were given relevant medicine intraperitoneally （0.01 mL/g）， once a day， for 6 consecutive weeks. The body weight and liver weight of mice were measured， and the pathological damage of liver tissue in mice was observed. The levels of aspartate aminotransferase （AST）， alanine aminotransferase（ALT）， and triglycerides （TG） in serum， as well as the protein expressions of nuclear factor-erythroid 2-related factor 2 （Nrf2） and heme oxygenase-1 （HO-1） in liver tissue were determined. In vitro NAFLD model was established by using 0.5 mmol/L oleic acid （OA） in HepG2 cells. Normal control group， NAFLD model group and eriodictyol low-， medium- and high-concentration groups （50， 100， 150 μmol/L） were set up. HepG2 cells in drug groups were treated with eriodictyol for 24 h at the time of modeling. The lipid deposition was observed in cells， and the levels of TG， malondialdehyde （MDA） and reactive oxygen species （ROS） as well as the phosphorylation levels of the mitogen-activated protein kinase （MAPK） signal pathway related proteins [extracellular signal-regulated kinase （ERK）， c- Jun N-terminal kinase （JNK）] and the protein expressions of Nrf2 and HO-1 were all determined. RESULTS In the in vivo experiment， compared with the NAFLD model group， the body weight， liver weight， the serum levels of AST， ALT and TG were all decreased significantly in eriodictyol low- and high-dose groups （except for serum level of AST in eriodictyol low-dose group） （P＜0.01）； liver lipid deposition was reduced significantly and the protein expressions of Nrf2 and HO-1 in liver tissues were further up-regulated （P＜0.01）. In the in vitro experiment， compared with the NAFLD model group， the lipid deposition in hepatocytes was reduced in eriodictyol low-， medium- and high-concentration groups （P＜0.01）， and the levels of ROS， MDA and TG were down-regulated （P＜0.05 or P＜0.01）； the phosphorylation levels of ERK and JNK were significantly down-regulated （P＜0.01）， while the protein expressions of Nrf2 and HO-1 were up-regulated significantly （P＜0.01）. CONCLUSIONS Eriodictyol can inhibit MAPK signaling pathway and activate Nrf2/HO-1 signaling pathway to alleviate NAFLD.
ABSTRACT
Mannose has recently drawn extensive attention for its substantial anti-cancer activities, but the underlying mechanism remains largely unclear. The aim of this study was to investigate the effects of mannose on experimental colitis-associated colorectal tumorigenesis and underlying mechanisms. Data clearly showed that at plasma concentrations achieved after oral administration, mannose slightly affected malignancy of tumor cells or tumor promoter-induced transformation of pre-neoplastic cells, but substantially suppressed manifestation of the M2-like phenotype of tumor-associated macrophages (TAMs) in a cancer cell and macrophage co-culture model. Mechanistically, mannose might greatly impair the production of tumor cell-derived lactate which has a critical role in the functional polarization of TAMs. Importantly, oral administration of mannose protected mice against colitis-associated colorectal tumorigenesis by normalizing TAM polarization. Collectively, these findings highlight the importance of TAMs in colorectal tumorigenesis, and provide a rationale for introducing mannose supplementation to patients suffering from inflammatory bowel diseases.
ABSTRACT
OBJECTIVE:To optimize the purification technology of total flavones from Ampelopsis grossedentala with macro-porous resins. METHODS:4 kinds of macroporous resins for the purification of total flavones from A. grossedentala were screened by using drug-loading amount,desorption rate,recovery and purification rate as indicators. Single factor test and central composite design-response surface methodology were used to optimized eluant mass fraction,adsorption time,flow rate of eluant,eluant pH and other factors of purification technology,and validation test was also conducted. RESULTS:D-101 macroporous resin was the best. The optimal condition was as follows as the concentration of sample solution 2 mg(by extract weight)/ml,the volume of sam-ple solution 1.1 BV,ethanol 86.0%,adsorption time 36.7 min,flow rate of eluant 3.81 BV/h,pH 7. In validation test,mass frac-tion of total flavones increased from 66.83% to 85.00% in validation test(RSD=0.15%,n=3),and were close to predicted val-ue(85.08%). CONCLUSIONS:Central composite design-response surface methodology is feasible and stable for the optimization of purification technology of total flavones from A. grossedentala with macroporous resins.
ABSTRACT
A high performance liquid chromatography-tandem mass spectrometric method ( HPLC-MS/MS ) was developed for the simultaneous determination of 31 kinds of triazine herbicides in farmland soils. Samples were extracted by accelerated solvent extraction ( ASE ) and purified by Oasis MCX solid phase extraction ( SPE) cartridges, and then analyzed by HPLC-MS/MS in multiple reaction monitoring ( MRM) mode with positive electrospray ionization. The analytical column was Phenomenex Luna C18 ( 150 mm í 2. 0 mm í3 μm) and the mobile phases were acetonitrile and water containing 0. 1% (V/V) formic acid. The limits of detection (S/N≥3) were 0. 008-0. 440 μg/L. All of the triazine herbicides had good linear responses with r≥0 . 996 and the average recoveries in the spiked levels of 0 . 40-40 . 0 μg/kg ranged from 76 . 9%-102 . 0%with the RSDs of 3 . 4%-10 . 3%. The HPLC-MS/MS method had been applied for the detection of the triazine herbicide residues in farmland soils from Shenyang region and the results showed that atrazine, simazine, prometryne and atrazine-desethyl were the main triazine herbicides in the region.
ABSTRACT
SYBR Green I Real Time-qPCR method was developed to quantify the numbers of copyies of AlkB ( alkanes degradation gene) and Nah ( naphthalene dioxygenase degradation gene) functional degradation gene corresponding to alkanes and aromatic hydrocarbons degradation. Two pairs of primers AlkBf/AlkBr and Nahf/Nahr were designed for AlkB and Nah amplification respectively, according to the nucleotide sequences of related degradation microorganisms published in GenBank. The purified recovery products of traditional PCR were combined with pEASY-T1 vectors and transformed in competent cells to amplify. The recombinant plasmids were extracted and used as positive templates to create standard curve through gradient dilution. The conditions for the real time PCR were as the follows: the final concentration of forward and reverse primers were 0. 2 μmol/L, 2×TransStart Top Green qPCR SuperMix, and the annealing temperatures of AlkB and Nah PCR were 50℃ and 57℃, respectively. The method showed a sensitivity of 100 times higher than that of the traditional PCR method and good repeatability. The numbers of copies of AlkB in three functional regions of an oilfield indicated that oil producing zone with serious oil pollution had the highest AlkB copy numbers, and residential zone with lighter oil pollution had the lowest AlkB copy numbers. Nah degradation gene distribution was more uniform.