[Chemical constituents of Psidium guajava and their antitumor and antifungal activities].

Twenty-six compounds, including sixteen meroterpenoids(1-16), a triterpenoid(17), four terpenoid derivatives(18-21), and five aromatic compounds(22-26), were isolated from the leaves of Psidium guajava. Their structures were identified by spectroscopic analyses including NMR and MS. Compounds 21-26 were obtained from plants of Psidium for the first time. Based on the structure,(R)-2-ethylhexyl 2H-1,2,3-triazole-4-carboxylate(24 a), an α-glucosidase inhibitor recently isolated from Paramignya trimera, should be revised as compound 24. Meroterpenoids 1-16 were evaluated for their antitumor and antifungal activities. Meroterpenoids psiguajadial D(4), guapsidial A(5), 4,5-diepipsidial A(7), guadial A(14), and guadial B(15) showed cytotoxicities against five human tumor cell lines(HL-60, A-549, SMMC-7721, MCF-7, and SW-480), among which 5 was the most effective with an IC_(50) of 3.21-9.94 µmol·L~(-1).

Effect of Tai Chi for the prevention or treatment of osteoporosis in elderly adults: protocol for a systematic review and meta-analysis.

INTRODUCTION: Osteoporosis (OP) has been defined as a degenerative bone disease characterised by low bone mass and microstructural deterioration of bone tissue, leading to fragility and an increased risk of fractures, especially of the hip, spine and wrist. Exercise has been shown to benefit the maintenance of bone health and improvement of muscle strength, balance and coordination, thereby reducing the risk of falls and fractures. However, prior findings regarding the optimal types and regimens of exercise for treating low bone mineral density (BMD) in elderly people are not consistent. As an important component of traditional Chinese Qigong exercises, Tai Chi (TC) is an ancient art and science of healthcare derived from the martial arts. The objective of this study is to attempt to conduct a systematic review and meta-analysis of the existing studies on TC exercise as an intervention for the prevention or treatment of OP in elderly adults and to draw more useful conclusions regarding the safety and the effectiveness of TC in preventing or treating OP. METHODS AND ANALYSIS: Eight electronic databases (Science Citation Index, PubMed Database, Embase (Ovid) Database, the Cochrane Central Register of Controlled Trials, and Chinese databases, including Chinese BioMedical Database, China National Knowledge Infrastructure, Wanfang database and the Chongqing VIP Chinese Science and Technology Periodical Database) will be searched from the beginning of each database to 1 April 2018. Potential outcomes of interest will include rates of fractures or falls, BMD at the total hip and the total spine, bone formation biomarkers, bone resorption biomarkers, bone biomarkers, health-related quality of life and adverse events. Only randomised controlled trials comparing TC exercise against each other or non-intervention will be included. The Cochrane risk of bias assessment tool will be used for quality assessment. ETHICS AND DISSEMINATION: Ethical approval is not required as the study will be a review of existing studies. This review may help to elucidate whether TC exercise is effective for the prevention or treatment of OP in elderly adults. The findings of the study will be published in a peer-reviewed publication and will be disseminated electronically or in print. We will share the findings in the fourth quarter of 2018. TRIAL REGISTRATION NUMBER: CRD42018084950.

Interleukin-18 Down-Regulates Multidrug Resistance-Associated Protein 2 Expression through Farnesoid X Receptor Associated with Nuclear Factor Kappa B and Yin Yang 1 in Human Hepatoma HepG2 Cells.

Multidrug resistance-associated protein 2 (MRP2) plays an important role in bile acid metabolism by transporting toxic organic anion conjugates, including conjugated bilirubin, glutathione, sulfate, and multifarious drugs. MRP2 expression is reduced in cholestatic patients and rodents. However, the molecular mechanism of MRP2 down-regulation remains elusive. In this report, we treated human hepatoma HepG2 cells with interleukin-18 (IL-18) and measured the expression of MRP2, nuclear factor kappa B (NF-κB), farnesoid X receptor (FXR), and the transcription factor Yin Yang 1 (YY1) by quantitative real-time quantitative polymerase chain reaction (PCR) and western blotting. We found that expression of MRP2 was repressed by IL-18 at both the mRNA and protein levels in a dose- and time-dependent manner. Furthermore, the activated NF-κB pathway increased YY1 and reduced FXR. These changes were all attenuated in HepG2 cells with knockdown of the NF-κB subunit, p65. The reduced expression of FXR and MRP2 in HepG2 cells that had been caused by IL-18 treatment was also attenuated by YY1 knockdown. We further observed significantly elevated IL-18, NF-κB, and YY1 expression and decreased FXR and MRP2 expression in bile duct-ligated Sprague Dawley rat livers. Chromatin immunoprecipitation assays also showed that FXR bound to the promoter region in MRP2 was less abundant in liver extracts from bile duct-ligated rats than sham-operated rats. Our findings indicate that IL-18 down-regulates MRP2 expression through the nuclear receptor FXR in HepG2 cells, and may be mediated by NF-κB and YY1.