Preparation and characterization of fenugreek leaf flavonoids and their protective effects against oxidative damage to hepatocytes / 中国中药杂志

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.

Research progress on chemical constituents and pharmacological activities of Trigonella foenum-graecum / 中国中药杂志

Trigonella foenum-graecum is an annual plant of the genus Trigonella in the Leguminosae family. It is widely distributed in China and has a long history of application. According to phytochemistry research, the seeds, stem, and leaves of this herb contain not only a variety of bioactive ingredients, including alkaloids, saponins, polysaccharides, flavonoids, and phenols, but also abundant nutrients such as unsaturated fatty acids and amino acids and various trace elements. Pharmacological studies have shown that both the extract of T. foenum-graecum and its chemical constituents exhibit hypoglycemic, hypolipidemic, antitumor, antioxidative, antimicro-bial, and hepatoprotective activities. This paper reviews the research progress on the chemical constituents and pharmacological effects of T. foenum-graecum, which may contribute to further development, application, and clinical research of this herb.

Protective effect of seed oil of Herpetospermum pedunculosum against carbon tetrachloride-induced liver injury in rats

To investigate the protective effect of Herpetospermum pedunculosum [H. pedunculosum] seed oil against carbon tetrachloride CC1[4] -induced liver damage. This experimental study was conducted at the Northwest Institute of Plateau Biology, Chinese Academy of Sciences, and Yantai University, China from November 2012 to May 2013. The H. pedunculosum seed oil was extracted using supercritical carbon dioxide. The antioxidant activities of H. pedunculosum seed oil were assayed in vitro by 2,2-diphenyl-l-picrylhydrazyl assay, lipid peroxidation assay, and antihemolytic assay. Adult Sprague Dawley rats were randomly divided into 6 groups [10 rats/group] including control, CC1[4], CCl[4]+bifendate, and CC[4]+H. pedunculosum seed oil [3 different doses] groups. The CCl[4]-induced liver lesions include hepatocyte necrosis, ballooning degeneration, calcification, and fibrosis. Moreover, CC1[4] damage results in an obvious increase of serum triglycerides, high-density lipoprotein, low-density lipoprotein, malondialdehyde, total bilirubin, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase activity. In addition, CC1[4] also significantly decreased the activities of superoxide dismutase [SOD]. By contrast, H. pedunculosum seed oil administration significantly ameliorated the CC1[4]-induced liver lesions, lowered the serum levels of hepatic enzyme markers, and increased the activities of SOD. The results of this study show that H. pedunculosum seed oil can be proposed to protect the - liver against CCl[4]-induced oxidative damage in rats, and the hepatoprotective effect might be correlated with its potent antioxidant and free radical scavenging effect