Natural constituents from Cortex Mori Radicis as new pancreatic lipase inhibitors.

Pancreatic lipase (PL), a key enzyme responsible for the hydrolysis of triacylglycerides in the gastrointestinal tract, has been identified as the therapeutic target for the regulation of lipid absorption. In the present study, six major constituents from a famous Chinese herbal medicine Cortex Mori Radicis (also named sangbaipi in Chinese), have been collected and their inhibitory effects on PL have been carefully investigated and well characterized by a fluorescence-based assay. The results clearly demonstrated that all tested bioactive constituents from Cortex Mori Radicis including sanggenone C (SC), sanggenone D (SD), kuwanon C (KC), kuwanon G (KG), morin and morusin displayed strong to moderate inhibitory effects towards PL with the IC50 values ranging from 0.77 µM to 20.56 µM. Further investigations on inhibition kinetics demonstrated that SC, SD, KC and KG functioned as potent and mixed inhibitors against PL-mediated 4-MU oleate hydrolysis, with the Ki values less than 5.0 µM. Furthermore, molecular docking simulations demonstrated that SD (the most potent PL inhibitor from Cortex Mori Radicis) could create strong interaction with Ser152 (the key amino acid in the catalytic triad) of PL via hydrogen bonding. All these findings provided a new powerful evidence for explaining the hypolipidemic effect of Cortex Mori Radicis, also suggested that some abundant natural compounds in this herbal medicine could be served as lead compounds for the development of new PL inhibitors.

Interspecies variation in phase I metabolism of bufalin in hepatic microsomes from mouse, rat, dog, minipig, monkey, and human.

1. Bufalin (BF), one of the major bioactive compounds in traditional Chinese medicine (TCM) Chansu, has been found with various pharmacological and toxicological effects. This study aims to investigate the species differences in phase I metabolism of BF in hepatic microsomes from human and five common experimental animals. 2. Metabolite profiling demonstrated that two major metabolites were formed in liver microsomes from human and animal species in NADPH-generating system. Two major metabolites were identified as 5ß-hydroxyl-bufalin and 3-keto-bufalin, with the help of authentic standards. CYP3A was assigned as the main isoform involved in both 5ß-hydroxylation and 3-oxidation in all studied liver microsomes. The apparent kinetic parameters including substrate affinity and catalytic efficiency for 5ß-hydroxylation and 3-oxidation of BF were also determined. 3. In summary, CYP3A mediated 5ß-hydroxylation and 3-oxidation were two major metabolic pathways of BF in hepatic microsomes from human and five studied animals, but kinetic analysis demonstrated that the intrinsic clearances of these two metabolic pathways were much different among various species. The qualitative and quantitative interspecies study indicated that minipig exhibited the similar metabolic profile, kinetic behaviors and intrinsic metabolic clearances of BF phase I biotransformation in comparison with that of human.

Anti-inflammatory and anti-nociceptive activities of Sipunculus nudus L. extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Sipunculus nudus has long been employed as traditional Chinese medicine in folk remedies for the treatment of carbuncles, tuberculosis and nocturia, regulating the functions of stomach and spleen, as well as for the restoration to health in debilities caused by various pathogens and aging. Decoction of Sipunculus nudus has traditionally been used to remedy sternalgia in folk medicine. AIM OF THE STUDY: This study aimed to assess the anti-inflammatory and anti-nociceptive activity of the water extract from Sipunculus nudus. MATERIALS AND METHODS: The water extract from the body wall of Sipunculus nudus was obtained with the yield of 14.1%. The anti-inflammatory effect in six animal models and anti-nociceptive effect in two animal models of the water extract were evaluated by oral for the study. RESULTS: Pretreatment with the extract (at the dose of 50, 100 and 200 mg/kg) produced significant dose-dependent anti-inflammatory and anti-nociceptive effects. At 200 mg/kg dose, the inhibition ratio of the extract on carrageenan-induced rat hind paw oedema, dextran-induced rat paw oedema, cotton pellet granuloma in rats, carrageenan-induced peritonitis and acetic acid-induced vascular permeability were 59.2%, 51.0%, 53.1%, 42.5%, 50.8%, better than that of indomethacin (5 mg/kg) 49.5%, 50%, 44.4%, 37.6%, 46.8%, respectively. The inhibition ratio of the extract (200 mg/kg dose) on xylene-induced mouse ear oedema was 61.5%, lower than 63.7% for indomethacin (5 mg/kg). At 200mg/kg, the extract decreased number of writhing 52.3% in acetic acid-induced writhing model and increased the response latency 25.24% in hot plate test. CONCLUSIONS: The water extract from the body wall of Sipunculus nudus possesses excellent anti-inflammatory activity as well as peripheral and central analgesic properties.