Characterization of the metabolites of GW1929 in rat by liquid chromatography coupled with electrospray ionization tandem mass spectrometry.

RATIONALE: GW1929 is a potent PPAR-γ activator. To fully understand its mechanism of action, it is necessary to study the in vitro and in vivo metabolism. METHODS: For in vitro metabolism, GW1929 was incubated with rat hepatocytes at 37°C for 2 h. For in vivo metabolism, rats were orally administered with GW1929 at a single dose of 10 mg/kg and plasma, urinary and fecal samples were collected at defined time points. All the samples were analyzed by the developed ultra-high-performance liquid chromatography combined with tandem mass spectrometry. The structures of metabolites were proposed according to their accurate masses and product ions. RESULTS: A total of 17 metabolites, including seven glucuronide conjugates, were detected and structurally identified. M4 (hydroxylation), M13 (demethylation) and M14 (hydroxylation) were the most abundant metabolites. The metabolic pathways of GW1929 referred to hydroxylation, demethylation, deamination and glucuronidation. CONCLUSIONS: The present study provided new information on the in vitro and in vivo metabolic profiles of GW1929 which will be helpful for a better understanding of the mechanism of the elimination of GW1929.

[Immunocompetence effects of polysaccharide of snakegourd root on human peripheral blood mononuclear cells in vitro].

OBJECTIVE: To establish the method of promoting human peripheral blood mononuclear cell proliferation by polysaccharide of snakegourd root and identify the effects of polysaccharide of snakegourd root on lymphocyte proliferation, T lymphocyte subsets and the different levels of TNF-alpha and IL-6. METHOD: The polysaccharide of snakegourd root preparations were purified with dialysis and ethanol precipitation. The healthy human PBMC were used as the target cells for screening potency of the drugs. MTT colorimetry was established to examine the levels of lymphocyte proliferation on human PBMC by polysaccharide of snakegourd root in vitro. The percents of lymphocyte subsets (CD3+, CD4+, CD8+ T lymphocyte) and the different levels of TNF-a and IL-6 in PBMC were analysed by FCM and ELISA, respectively. RESULT: 1.0-50.0 mmol x L(-1) of polysaccharides of snakegourd root showed the significant effects of promoting proliferation of human PBMC (P < 0.05). The percents of CD3+, CD4+, CD8+ T lymphocytes in PBMC treated with 5.0 and 10.0 mmol x L(-1) of polysaccharides of snakegourd root were significantly higher than those of the control group (P < 0.05). The levels of TNF-alpha and IL-6 were significantly higher than those of the control group after 1.0, 5.0, 10.0 mmol x L(-1) of polysaccharides of snakegourd root stimulation on the human PBMC at 8 hours (P < 0.05). CONCLUSION: The significant effects on promoting lymphocyte proliferation and activation of the polysaccharide of snakegourd root are confirmed in this study. The percents of lymphocyte subsets are increased in different degrees by the polysaccharide of snakegourd root. The high levels of TNF-alpha and IL-6 are secreted after the polysaccharides of snakegourd root stimulation on the human PBMC, which lays a foundation for further elucidating the immunocompetence effects and mechanism of the polysaccharide of snakegourd root.