Jiangxienone, a new compound with potent cytotoxicity against tumor cells from traditional Chinese medicinal mushroom Cordyceps jiangxiensis.

A new compound, named jiangxienone, has been isolated from a culture of the traditional Chinese medicinal mushroom Cordyceps jiangxiensis, and its chemical structure was established on the basis of spectroscopic and chemical techniques. Jiangxienone showed potent cytotoxic effects against human gastric adenocarcinoma SGC-7901 cell and human lung carcinoma A549 cell with IC(50) values ranging from 1.38 to 2.93 µM, i.e., with at least approximately six-fold stronger cytotoxicity than cisplatin, a first-line chemotherapy drug for cancer patients.

Establishment of a cell-based drug screening model for identifying agonists of human peroxisome proliferator-activated receptor gamma (PPARγ).

OBJECTIVES: Peroxisome proliferator-activated receptor gamma (PPARγ) plays a critical role in regulation of diverse biological processes, including lipid metabolism and adipogenesis, cell division and apoptosis, and is involved in variety of disease conditions, such as obesity, atherosclerosis, inflammation and tumour. Developing a cell-based reporter gene model targeting PPARγ would be useful to screen human PPARγ agonists that could be beneficial to patients with these diseases. METHODS: We stably co-transfected human embryonic kidney (HEK) cell line 293T cells with phPPARγ-IRES2-EGFP vector to express human PPARγ (hPPARγ), a reporter vector pPPRE×3-TK-LUC, and control vector pRL-CMV. The efficiency of the co-transfection was evaluated with flow cytometry of hPPARγ expressing cells. Specificity of hPPARγ activity was determined by dual luciferase reporter assay of co-transfected cells exposed to PPARγ agonist rosiglitazone, PPARα agonist WY14643 and retinoic acid receptor alpha (RARα) agonist all-trans-retinoic acid (ATRA). KEY FINDINGS: The phPPARγ-IRES2-EGFP co-transfected HEK293T cells showed concentration- and time-dependent luciferase induction upon exposure to the rosiglitazone, while WY14643 and ATRA were unable to activate the co-transfected HEK293T cells. CONCLUSIONS: These data indicated that the HEK293T cells could be stably transfected with hPPARγ. This cell-based drug screening platform could be used targeting specific nuclear receptor of hPPARγ with effectiveness and specificity for hPPARγ agonists discovery.

Polysaccharides from the Medicinal Mushroom Cordyceps taii Show Antioxidant and Immunoenhancing Activities in a D-Galactose-Induced Aging Mouse Model.

Cordyceps taii, an edible medicinal mushroom native to south China, is recognized as an unparalleled resource of healthy foods and drug discovery. In the present study, the antioxidant pharmacological properties of C. taii were systematically investigated. In vitro assays revealed the scavenging activities of the aqueous extract and polysaccharides of C. taii against various free radicals, that is, 1,1-diphenyl-2-picrylhydrazyl radical, hydroxyl radical, and superoxide anion radical. The EC(50) values for superoxide anion-free radical ranged from 2.04 mg/mL to 2.49 mg/mL, which was at least 2.6-fold stronger than that of antioxidant thiourea. The polysaccharides also significantly enhanced the antioxidant enzyme activities (superoxide dismutase, catalase, and glutathione peroxidase) and markedly decreased the malondialdehyde production of lipid peroxidation in a D-galactose-induced aging mouse model. Interestingly, the immune function of the administration group was significantly boosted compared with the D-galactose-induced aging model group. Therefore, the C. taii polysaccharides possessed potent antioxidant activity closely associated with immune function enhancement and free radical scavenging. These findings suggest that the polysaccharides are a promising source of natural antioxidants and antiaging drugs. Consequently, a preliminary chemical investigation was performed using gas chromatography-mass spectroscopy and revealed that the polysaccharides studied were mainly composed of glucose, mannose, and galactose. Fourier-transform infrared spectra also showed characteristic polysaccharide absorption bands.