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Tetrandrine is an effective ingredient isolated from the roots of a frequently used medicinal plant Stephania tetrandra S. Moore. It has been used for the management of arthritis in China, but the precise mechanism remains unclear. In the present study, a metabolomics method based on the 1 H NMR was constituted to quantify the alterations of the endogenous metabolites in the urines of collagen-induced arthritis (CIA) rats treated with tetrandrine. Data showed that tetrandrine treatment could alleviate the ankle joint swelling and ameliorate histopathological changes in rats. The metabonomic analysis indicated that 23 potential biomarkers in urine were affiliated with CIA. They mainly participated in energy metabolism, amino acid metabolism, lipid metabolism and gut microbe metabolism. Moreover, our results implied that tetrandrine could reverse the pathological process of CIA through adjusting the unbalanced metabolic pathways. Thus, these metabolic pathways and potential biomarkers might be the potential therapeutic targets of tetrandrine, and these findings supplied new visions into the protective effect of tetrandrine against arthritis in rats. [ABSTRACT FROM AUTHOR]

Emamectin benzoate (EMB), a novel macrocyclic lactone insecticide, possesses high efficacy and beneficial selective toxicity in agriculture, but so far the EMB-induced cytotoxic action in arthropod insect remains unclear. The present studies were carried out to characterize the property of EMB on the induction of reactive oxygen species (ROS)-mediated DNA damage and apoptosis in Trichoplusia Tn5B1-4 cell model. Following the exposure to EMB at 2.5, 5, 10 or 15 μM, the cells changed to be round, suspended and aggregated, and the decline of cell proliferating ability and cell viability was positively related with the exposure time. Median inhibitory concentration (IC 50 ) of EMB on cell viability was 3.72 μM during 72 h exposure. Apoptosis was induced in 29.8% (24 h) and 39.5% (48 h) of the cells by EMB at 15 μM, showing chromatin condensation in nuclei. The content of ROS in the cells increased rapidly as the concentration of EMB increased, and the pre-incubation of the cells with vitamin E significantly reduced the ROS accumulation. In the treatment of 15 μM EMB, the migrated cell nucleus with DNA strand breaks appeared a teardrop, pear-shaped, or large fan-like tail, and 63.1% of γH2AX-positive cells contained more than four foci, accompanying with high expression level of caspase-3 in time-dependent manner, which consequently led to cell apoptotic death. These evidences in ROS-mediated DNA damage and cell apoptosis induced by EMB may be helpful for deep understanding the cytotoxic action of EMB based on cell model. [ABSTRACT FROM AUTHOR]

Leukemia threatens millions of people's health and lives, and the pesticide-induced leukemia has been increasingly concerned because of the etiologic exposure. In this paper, cytotoxic effect of emamectin benzoate (EMB), an excellent natural-product insecticide, was evaluated through monitoring cell viability, cell apoptosis, mitochondrial membrane potential and intracellular Ca 2+ concentration ([Ca 2+ ] i ) in leukemia K562 and Molt-4 cells. Following the exposure to EMB, cell viability was decreased and positive apoptosis of K562 and Molt-4 cells was increased in a concentration- and time- dependent fashion. In the treatment of 10 μM EMB, apoptotic cells accounted for 93.0% to K562 cells and 98.9% to Molt-4 cells based on the control, meanwhile, 63.47% of K562 cells and 81.15% of Molt-4 cells exhibited late apoptotic and necrotic features with damaged cytoplasmic membrane. 48 h exposure to 10 μM EMB increased significantly the great number of cells with mitochondrial membrane potential (MMP) loss, and the elevation of [Ca 2+ ] i level was peaked and persisted within 70 s in K562 cells whilst 50 s in Molt-4 cells. Moreover, a stronger cytotoxicity of EMB was further observed than that of imatinib. The results authenticate the efficacious effect of EMB as a potential anti-leukemia agent and an inconsistency with regard to insecticide-induced leukemia. [ABSTRACT FROM AUTHOR]

Photodynamic sensitizers as useful alternative agents have been used for population control against insect pests, and the response of insect ovarian cells towards the photosensitizers is gaining attention because of the next reproduction. In this paper, antioxidative responses of lepidopteran ovarian Tn5B1-4 and Sf-21 cells to photoactivated alpha-terthienyl (PAT) are investigated. PAT shows positive inhibitory cytotoxicity on the two ovarian cells, and its inhibition on cell viability is enhanced as the concentrations are increased and the irradiation time is extended. Median inhibitory concentrations (IC 50 ) are 3.36 μg/ml to Tn5B1-4 cells, and 3.15 μg/ml to Sf-21 cells at 15 min-UV-A irradiation 2 h-dark incubation. Under 10.0 μg/ml PAT exposure, 15 min-UV-A irradiation excites higher ROS production than 5 min-UV-A irradiation does in the ovarian cells, the maximum ROS content is about 7.1 times in Tn5B1-4 cells and 4.3 times in Sf-21 cells, and the maximum malondialdehyde levels in Tn5B1-4 and Sf-21 cells are about 1.47- and 1.36-fold higher than the control groups, respectively. Oxidative stress generated by PAT strongly decreases the activities of POD, SOD and CAT, and induces an accumulation of Tn5B1-4 cells in S phase and Sf-21 cells in G2/M phase in a concentration-dependent fashion. Apoptosis accumulation of Tn5B1-4 cells and the persistent post-irradiation cytotoxicity are further observed, indicating different antioxidative tolerance and arrest pattern of the two ovarian cells towards the cytotoxicity of PAT. [ABSTRACT FROM AUTHOR]

[Display omitted] Madecassic acid (MA), a triterpene compound isolated from Centella Asiatica herbs, has previously been shown to attenuate colitis induced by DSS in mice. In the present study, we address whether and how MA ameliorates colitis-associated colorectal cancer (CAC), which accounts for a considerable proportion of colorectal cancer. CAC was induced by AOM/DSS in mice, and MA was administered orally once a day. To identify the source cells of IL-17 and the target cells for MA reducing the expression of IL-17 in the colons of CAC mice, single-cell suspensions were prepared from the colons of CAC mice and analyzed by flow cytometry. An adoptive transfer experiment was performed to verify the importance of the decreasing γδT17 cell population in the anti-CAC effect of MA. Oral administration of MA reduced the burden and incidence of tumors in the CAC mice. MA decreased the number of MDSCs in the colon tissues of CAC mice and ameliorated anti-tumor immune responses. MA could prevent the migration of MDSCs by inhibiting the activation of γδT17 cells and the expression of chemokines. The population of activated-γδT17 cells in the tumor microenvironment of CAC mice positively correlated with the number of MDSCs and tumors as well as tumor load. Moreover, the anti-CAC effect of MA was significantly counteracted by the adoptive transfer of γδT17 cells. MA alleviates CAC by blocking the recruitment of MDSCs to increase the population of anti-tumor immune cells in tumor microenvironment via inhibition of the activation of γδT17 cells. [ABSTRACT FROM AUTHOR]

Abstract Aims Sinomenine, an anti-rheumatoid arthritis drug used in China for decades, is usually co-administered with cardiovascular (CV) drugs to reduce arthritis-related risk of cardiovascular diseases. This study was to investigate whether and how CV drugs affect the pharmacokinetic profile of sinomenine. Main methods In rat liver microsomes (RLMs), the key metabolic enzymes of sinomenine were identified by using specific inhibitors. The influences of CV drugs, including propranolol, verapamil, warfarin, atorvastatin, simvastatin, and lovastatin, on the metabolism of sinomenine were examined. Cocktail probe, RT-qPCR, and western blotting were performed to unveil the underlying mechanism of the drug-drug interaction. Key findings The key metabolic enzymes of sinomenine were identified to be CYP3A1/2 and CYP2D1 in RLMs. Among the CV drugs screened, simvastatin and lovastatin were shown to inhibit the liver metabolism of sinomenine with Ki values of 13.00 and 25.83 μM, respectively. Single administration of simvastatin or lovastatin in rats increased the AUC value of sinomenine to 1.40- or 1.50-fold, and decreased the CLz/F value to 68.19% or 65.44%, respectively. In contrast, multiple administrations of simvastatin, but not lovastatin, increased the CLz/F value of sinomenine to 1.38-fold and decreased the AUC value to 71.59%. Further studies showed that the long-term administration of simvastatin could up-regulate the expression of CYP3A1/2 to account for the effect. Significance This study demonstrated the potential effect of simvastatin and lovastatin on the metabolism of sinomenine for the first time. The findings provide guidelines for the co-administration of sinomenine with simvastatin or lovastatin in clinic. [ABSTRACT FROM AUTHOR]

Arctigenin, the major active constituent of Fructus Arctii, has been reported to inhibit the growth of various tumors and alleviate colitis. This study aimed to prove the protective effect of arctigenin on colitis-associated cancer (CAC) and explore its mechanisms. Orally administered arctigenin prevented the progression of colitis and protected against colon carcinogenesis in azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced CAC mice. Arctigenin downregulated NLRP3 inflammasome activation and fatty acid oxidation (FAO) metabolism in macrophages, as determined by untargeted metabolomics. Arctigenin also inhibited the expression of carnitine palmitoyltransferase 1 (CPT1), reduced the acetylation of α-tubulin, and disrupted NLRP3 complex formation, which in turn inactivated the NLRP3 inflammasome. Downregulation of the CPT1-FAO-acetyl-coenzyme A (acetyl-CoA)-acetylated α-tubulin pathway was observed to inhibit the effect of arctigenin on NLRP3 inflammasome assembly, as confirmed by CPT1 overexpression. Lastly, arctigenin was shown to inhibit NLRP3 inflammasome activation and improve CAC in mice, and the effect was significantly diminished by the overexpression of adeno-associated virus (AAV)9-CPT1. Taken together, these results show that the inhibition of NLRP3 inflammasome assembly in macrophages due to FAO downregulation contributes to the preventative effect of arctigenin against CAC. Our findings highlight the potential value of arctigenin to reduce the risk of CAC in patients with colitis. [ABSTRACT FROM AUTHOR]

Intestinal epithelial barrier dysfunction is deeply involved in the pathogenesis of inflammatory bowel diseases (IBD). Arctigenin, the main active constituent in Fructus Arctii (a traditional Chinese medicine), has previously been found to attenuate colitis induced by dextran sulfate sodium (DSS) in mice. The present study investigated whether and how arctigenin protects against the disruption of the intestinal epithelial barrier in IBD. Arctigenin maintained the intestinal epithelial barrier function of mice with DSS‐ and TNBS‐induced colitis. In Caco‐2 and HT‐29 cells, arctigenin lowered the monolayer permeability, increased TEER, reversed the abnormal expression of tight junction proteins, and restored the altered localization of F‐actin induced by TNF‐α and IL‐1β. The specific antagonist PHTPP or shRNA of ERβ largely weakened the protective effect of arctigenin on the epithelial barrier function of Caco‐2 and HT‐29 cells. Molecular docking demonstrated that arctigenin had high affinity for ERβ mainly through hydrogen bonds as well as hydrophobic effects, and the protective effect of arctigenin on the intestinal barrier function was largely diminished in ERβ‐mutated (ARG346 and/or GLU305) Caco‐2 cells. Moreover, arctigenin‐blocked TNF‐α induced increase of the monolayer permeability in Caco‐2 and HT‐29 cells and the activation of myosin light chain kinase (MLCK)/myosin light chain (MLC) pathway in an ERβ‐dependent manner. ERβ deletion in colons of mice with DSS‐induced colitis resulted in a significant attenuation of the protective effect of arctigenin on the barrier integrity and colon inflammation. Arctigenin maintained the integrity of the intestinal epithelial barrier under IBD by upregulating the expression of tight junction proteins through the ERβ‐MLCK/MLC pathway. [ABSTRACT FROM AUTHOR]