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Aim To study the protective effect of trigonelline on H
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Aim To study the effect of Rubus irritans Focke extract on adipogenic differentiation of 3T3-L1 preadipocytes, and to further explore the potential mechanism of Rubus irritans Focke on adipocyte metabolism, so as to provide a new basis for the prevention and treatment of obesity. Methods Rubus irritans Focke extract was separated and prepared by MCI medium pressure chromatographic column. MTT method was used to detect cell proliferation, and oil red 0 staining and kit test was used to to detect the level of lipid accumulation. Western blot was employed to detect the expressions of peroxisome proliferator-activated receptor ¦y (PPAR7), CCAAT enhancer binding protein a (C/ EBPa), adenosine 5'-monophosphate activated protein kinase (AMPK) and phosphorylated AMPK (p-AMPK) protein. Results When the concentration of Rubus irritans Focke extract was less than 100 mg •L
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Aim To explore the effect of four stilbenes including rhaponticin, desoxyrhaponticin, rhapontigenin and resveratrol on glucose and lipid metabolism in insulin-resistant HepG2 cells induced by high glucose and high fat. Methods The model of insulin resistance was established by incubating HepG2 cells with a complex of glucose and oleic acid. MTT assay was used to detect cell viability. The intracellular triglyceride (TG) and glucose levels were measured by the kit method. The lipid production was observed by oil red O staining, and the cell morphology and uptake of 2-NBDG were observed by confocal microscope. The PPAR signaling pathway and PI3K/Akt insulin signaling pathway related proteins were determined by Western blot to evaluate the effect of stilbenes on glycolipid metabolism in IR-HepG2 cells. Results The complex containing 50 mmol • L
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The present study investigated the main components of fenugreek(Trigonella foenum-graecum L.) leaf flavonoids(FLFs) and their antioxidant activity. FLFs were prepared and enriched by solvent extraction, and the flavonoids were characterized by high-performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry(HPLC-Q-TOF-MS/MS). The protective effect of FLFs against H_2O_2-induced stress damage to L02 hepatocytes was also investigated. Firstly, the cell viability was measured by MTT assay. The oxidative stress injury model was induced by H_2O_2 in L02 cells. The release of lactate dehydrogenase(LDH), the content of reduced glutathione(GSH) and malondialdehyde(MDA), and the activities of superoxide dismutase(SOD) and catalase(CAT) were measured by assay kits. Hoechst fluorescence staining was performed to observe the cell apoptosis. The expression levels of c-Jun N-terminal kinase(JNK), extracellular signal-regulated kinase 1/2(ERK1/2), nuclear factor erythroid-2 related factor 2(Nrf2), heme oxygenase 1(HO-1), and their phosphorylated proteins were detected by Western blot. Based on the MS fragment ion information and data in databases, FLFs contained eight flavonoids with quercetin and kaempferol as the main aglycons. The cell viabi-lity assay revealed that as compared with the conditions in the H_2O_2 treatment group, 3.125-25 μg·mL~(-1) FLFs could increase the viability of L02 cells, reduce LDH release and MDA content in a dose-dependent manner, potentiate the activities of SOD, CAT, and GSH, decrease the phosphorylation of JNK and ERK1/2 proteins, and up-regulate the expression of Nrf2 and HO-1. The results of fluorescence staining showed that the nucleus of the H_2O_2 treatment group showed concentrated and dense strong blue fluorescence, while the blue fluorescence intensity of the FLFs group decreased significantly. FLFs showed a protective effect against H_2O_2-induced oxidative damage in L02 cells, and the underlying mechanism is associated with the enhancement of cell capability in clearing oxygen free radicals and the inhibition of apoptosis by the activation of the MAPKs/Nrf2/HO-1 signaling pathway. The antioxidant effect of fenugreek leaf is related to its rich flavonoids.