Pingwei San ameliorates dextran sulfate sodium-induced chronic colitis in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Ping weisan (PWS), a famous traditional Chinese medicinal, is published in the Prescriptions of Taiping Benevolent Dispensary. PWS has been proven to be effective for many diseases, especially chronic diseases. AIM OF THE STUDY: The purpose of this study was to investigate the effect and potential mechanism of PWS on chronic colitis in mice. MATERIALS AND METHODS: Chronic colitis was induced in mice using 2.5% DSS for two cycles of 5 days, and different doses of PWS (2, 4, 8 g/kg) were administered throughout the experiment. The disease activity index (DAI), length of colon and pathological changes were measured. Cytokine levels in vivo and in vitro were detected by ELISA. The protein levels of TLR4, PPARγ and the key proteins in NF-κB pathway and NLRP3 inflammasome were measured by western blot. RESULTS: PWS decreased DSS-induced DAI, colon length shortening and colonic pathological damage. PWS also reduced TNF-α, IL-1ß and IL-12 production. In addition, PWS suppressed NF-κB pathway activation by regulating the expression of TLR4 and PPARγ. Our data also indicated that PWS could inhibit NLRP3 inflammasome activation. CONCLUSIONS: PWS treatment alleviated the degree of colitis caused by DSS, suggesting that PWS might be a novel agent for the treatment of chronic colitis.

Acetylation Enhances TET2 Function in Protecting against Abnormal DNA Methylation during Oxidative Stress.

TET proteins, by converting 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), are hypothesized, but not directly shown, to protect promoter CpG islands (CGIs) against abnormal DNA methylation (DNAm) in cancer. We define such a protective role linked to DNA damage from oxidative stress (OS) known to induce this abnormality. TET2 removes aberrant DNAm during OS through interacting with DNA methyltransferases (DNMTs) in a "Yin-Yang" complex targeted to chromatin and enhanced by p300 mediated TET2 acetylation. Abnormal gains of DNAm and 5hmC occur simultaneously in OS, and knocking down TET2 dynamically alters this balance by enhancing 5mC and reducing 5hmC. TET2 reduction results in hypermethylation of promoter CGIs and enhancers in loci largely overlapping with those induced by OS. Thus, TET2 indeed may protect against abnormal, cancer DNAm in a manner linked to DNA damage.

[Simultaneous determination of gallic acid and hesperidin contained in Xiaogu capsule by HPLC].

OBJECTIVE: To develop an HPLC method for simultaneous determination of gallic acid and hesperidin in Xiaogu capsule, in order to provide a simple, rapid and accurate method for quality control of the compound preparation of traditional Chinese medicine. METHOD: Xiaogu capsule was extracted with methanol heating reflux method. Synergi 4 mu Hydro-RP 80A (4.6 mm x 250 mm, 5 microm) was adopted as the chromatographic column, with acetonitrile--0.04 mol x L(-1) phosphate monobasic sodium solution (20: 80) as the mobile phase. The flow rate was 1.0 mL x min(-1), the detection wavelength was 283 nm, and the column temperature was 25 degrees C. RESULT: Under the conditions, gallic acid and hesperidin reached the baseline resolved peak, with a good linearity within the range of 21.6-216.0 mg x L(-1) (r = 0.999 93) for gallic acid, and 4.5-45.0 mg x L(-1) (r = 0.999 95) for hesperidin, respectively. Their average recoveries (n = 9) were 101.5% (RSD 3.7%) and 94.7% (RSD 2.7%), respectively. The average contents of gallic acid and hesperidin contained in Xiaogu capsule were detected to 5.10% and 0.091 1%, respectively. CONCLUSION: The method established in this study can determine the content of gallic acid and hesperidin contained in Xiaogu capsule in a rapid and accurate manner, which provided reference for quality evaluation of the medicine.