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As a model organism, zebrafish have many advantages over other animal models and is suitable for studies on establishment of human disease model and mechanism.In zebrafish, there are two phases of endocrine formation during early development, which are directed by concomitant activity of many signaling pathways.Zebrafish pancreas possess similar cell structure with that of other animals, which can express various endocrine hormones including insulin.The main organs required for metabolic control, such as the pancreas, islet, and insulin sensitive tissue (muscle, liver) are conserved in zebrafish, and the mechanisms of glucose regulation in zebrafish is similar to that seen in mammalian models.These render it an excellent model to study glucose metabolism.Hyperglycemia in zebrafish model can be induced by administration of the diabetogenic drug, streptozotocin (STZ), alternatively immersion of the fish in glucose solution and water, or disturbing of signaling pathways associated with glucose metabolism.Glucose levels in adult zebrafish blood or embryo tissue and phenotype of retinal cell layers or retinal vasculature are the commonly used measurement organs in zebrafish diabetic models.
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Aim To study the effect of rhein on renal damage induced by aristolochic acid. Methods Ze-brafish model of aristolochic acid nephropathy, genera-ted by treating zebrafish larvae with aristolochic acid for 24 h, was treated with rhein simultaneously . Mor-pholigical changes were observed and the creatinine level in larvae tissue was measured. And mRNA ex-pression levels of inflammatory factor cox2 a and fibrosis factor TGF-β1 in larvae tissue were detected using qPCR. Results Some larvae show periocular edema and circulation system defection e. g. weak heart beat, narrow cardiac vesicle, decreased blood flow and even blockage , with a dose-response relationship after expo-sure to aristolochic acid for 24 h. The creatinine level in larvae tissue of the treated group was significantly higher than that of the control larvae. And the expres-sion levels of cox2 a and TGF-β1 in larvae tissue of the treated group were also significantly increased. Per-centage of abnormal larvae and creatinine level in lar-vae tissue were decreased when treated with rhein sim-ultaneously. And the expression levels of cox2a was down-regulated by rhein compared with the aristolochic acid treated group. But rhein had no effect on TGF-β1 expression. Conclusion To some extent rhein can protect renal from damage induced by aristolochic acid.
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To study the chemical constituents of K. oblongifolia, silica gel column chromatography, MCI and Sephadex LH-20 were used to separate the 70% acetone extract of the stems of K. oblongifolia. The structures of the isolated compounds have been established on the basis of physicochemical and NMR spectroscopic evidence as well as ESI-MS in some cases. Twenty compounds were obtained and identified as heteroclitalignan A (1), kadsulignan F (2), kadoblongifolin C (3), schizanrin F (4), heteroclitalignan C (5), kadsurarin (6), kadsulignan O (7), eburicol (8), meso-dihydroguaiaretic acid (9), kadsufolin A (10), tiegusanin M (11), heteroclitin B (12), (7'S)-parabenzlactone (13), angeloylbinankadsurin B (14), propinquain H (15), quercetin (16), kadsulignan P (17), schizanrin G (18), micrandilactone C (19) and (-)-shikimic acid (20). Compouds 1, 5, 8, 11-15, 18 and 20 were isolated from this plant for the first time. Toxicity of compounds 1-10 were evaluated with zebrafish model to observe the effect on its embryonic development and heart function. The results showed that compounds 7, 9 and 10 caused edema of zebrafish embryo and decreased the heart rate of zebrafish, which exhibited interference effect on heart development of zebrafish.
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Aim To study the cardiotoxicity of celastrol to zebrafish embryo.Method 48 h post-fertilization zebrafish embryos were used as model for analysis of heart toxicity and were treated with various concentrations of celastrol.6,12,24 h after treatment morphological and functional changes of embryos hearts were observed.Results Cardiotoxicity was not found in embryos during 24 h treatment with 1 ?mol?L-1 concentration of celastrol.Toxic symptoms of embryos were caused by 2,3,4 ?mol?L-1 concentrations of celastrol with appearance of heart linearization,heart membrane hemorrhage and hemocytes accumulation in cardiac region.Moreover,heart rate decreased significantly with increase of concentration and prolongation of treatment.The EC50(24 h)of decrease of heart rate was about 1.78 ?mol?L-1.Conclusion Celastrol is cardiotoxic to zebrafish embryo.