ABSTRACT
Studies have found that metformin is not only the preferred drug for lowering blood sugar, but also shows lipid-lowering and weight-loss effects. The purpose of this study was to use a hyperlipidemia hamster model to investigate the lipid-lowering effect of metformin and its effect on important metabolic pathways in lipid metabolism disorders. Fifty golden hamsters were divided into a control group, a model group, metformin high- and low-dose groups, and a simvastatin group. A high-fat diet was fed for 1 week to create the model, and then drug was administered for 11 weeks with the high-fat diet. Serum was taken for measurement of blood lipid and blood glucose at 2, 6, and 9 weeks after administration, and at weeks 3, 5, and 9 feces and urine were collected for 1H NMR metabolomics tests. After 11 weeks of intravenous injection of [U-13C6] glucose, serum was collected for a 13C NMR metabolic flux test. The results showed that the administration of metformin can significantly reduce blood lipids and glucose levels and can significantly affect metabolic pathways such as sugar metabolism, lipid metabolism, ketone metabolism, amino acid metabolism, and intestinal flora metabolism. The results of the metabolic flux analysis showed that the high-fat diet reduced the metabolism of tricarboxylic acids by 37.48%. After administration of low and high doses of metformin the metabolism of tricarboxylic acid increased by 98.14% and 143.10%, respectively. After administration of simvastatin tricarboxylic acid metabolism increased by 33.18%. The results indicate that metformin has a significant effect on promoting energy metabolism. This study used a combination of metabolomics and metabolic flow to explore the effect of metformin on lipid metabolism disorders and quantifies changes in the key pathway of energy metabolism-the tricarboxylic acid cycle. This study provides useful information for the study of the efficacy and mechanism of metformin, as well as a practical technical method for the screening of lipid-lowering drugs based on a hamster model.
ABSTRACT
Heart failure is the end stage of many cardiovascular diseases. It seriously affects the safety and quality of life of nearly 40 million people worldwide. At present, the clinical and pathophysiological characteristics of some types of heart failure are unknown, and there is no effective diagnosis and treatment. In recent years, genomics, transcriptomics, epigenomics, proteomics, metabolomics and other omics technologies have been widely used in disease research, providing new opportunities for the prevention, diagnosis and treatment of diseases. These strategies have also brought hope for the reduction in heart failure mortality. Based on the current status of clinical treatment of heart failure, this article reviews the roles and potential applications of these various omics technologies and their opportunities in the study of the pathogenesis of heart failure, clinical diagnosis and treatment, and related drug pharmacodynamics and mechanism of action.
ABSTRACT
We previously reported that tranilast can halt the pathogenesis of chronic cyclosporine nephrotoxicity in rats via the transforming growth factor-beta [TGF-beta] /Smad pathway, an important signaling system involved in epithelialmesenchymal transition [EMT], but the exact underlying cellular mechanisms are not yet clear. Thus, by selecting [0]TGF-beta1-induced normal rat kidney proximal tubular epithelial cells [NRK-52E] as a model, we demonstrated potential modifying effect of tranilast on EMT-induced by TGF-beta1 in vitro. NRK-52E cells were incubated with the blank vehicle [Dulbecco's modified Eagle's medium and F-12 [DMEM/F12] added with 10% fetal bovine serum [FBS]], 10 ng/ml TGF-beta1 alone or together with 100, 200 or 400microM tranilast for 48 h after incubation in medium containing 1% FBS for 24 h. Cell morphological changes were observed to confirm occurrence of EMT. Protein expressions of two typical markers of EMT, E-cadherin and alpha-smooth muscle actin [alpha-SMA], were assessed by western blotting and flow cytometry, respectively. Our results showed that TGF-beta1 induced spindle-like morphological transition, the loss of Ecadherin protein and upregulation of expression of alpha-SMA. However, the TGF-beta1-produced changes in cellular morphology, E-cadherin and alpha-SMA were inversed by tranlilast in concentration-dependent manner. Our findings indicate that tranilast can directly inhibit EMT. Thus, it may be implied that regulation of EMT be the target to prevent renal tubulointerstitial fibrosis.