Yi-Nan Zheng

Anti-obesity effects of chikusetsusaponins isolated from Panax japonicus rhizomes

BackgroundThe rhizomes of Panax japonicus are used as a folk medicine for treatment of life-style related diseases such as arteriosclerosis, hyperlipidemia, hypertension and non-insulin-dependent diabetes mellitus as a substitute for ginseng roots in China and Japan. Obesity is closely associated with life-style-related diseases. This study was performed to clarify whether chikusetsusaponins prevent obesity induced in mice by a high-fat diet for 9 weeks.MethodsWe performed two in vivo experiments. In one, female ICR mice were fed a high-fat diet with or without 1 or 3% chikusetsusaponins isolated from P. japonicus rhizomes for 9 weeks. In the other, lipid emulsion with or without chikusetsusaponins was administered orally to male Wistar rats, and then the plasma triacylglycerol level was measured 0.5 to 5 h after the orally administered lipid emulsion. For in vitro experiments, the inhibitory effects of total chikusetsusaponins and various purified chikusetsusaponins on pancreatic lipase activity were determined by measuring the rate of release of oleic acid from triolein in an assay system using triolein emulsified with lecithin.ResultsTotal chikusetsusaponins prevented the increases in body weight and parametrial adipose tissue weight induced by a high-fat diet. Furthermore, consumption of a high-fat diet containing 1 or 3% total chikusetsusaponins significantly increased the fecal content and triacylglycerol level at day 3 compared with the high-fat diet groups. Total chikusetsusaponins inhibited the elevation of the plasma triacylglycerol level 2 h after the oral administration of the lipid emulsion. Total chikusetsusaponins, chikusetsusaponin III, 28-deglucosyl-chikusetsusaponin IV and 28-deglucosyl-chikusetsusaponin V inhibited the pancreatic lipase activity.ConclusionThe anti-obesity effects of chikusetsusaponins isolated from P. japonicus rhizomes in mice fed a high-fat diet may be partly mediated through delaying the intestinal absorption of dietary fat by inhibiting pancreatic lipase activity. The present study clearly indicated that the saponin fractions of P. japonicus rhizomes had a significant anti-obesity action and supports the traditional usage as a substitute drug for ginseng roots.

Saponins (Ginsenosides) from stems and leaves of Panax quinquefolium prevented high-fat diet-induced obesity in mice

The present study was performed to clarify whether the crude saponins from stems and leaves of Panax quinquefolium inhibited lipase activity in vitro, and prevented obesity induced in mice by feeding a high-fat diet for 8 weeks. For in vitro experiments, assay for the inhibitory effects of saponins from stems and leaves of Panax quinquefolium on pancreatic lipase activity was performed by measuring the rate of release of oleic acid from triolein. For in vivo experiments, female ICR mice were fed a high-fat diet with or without saponins from stems and leaves of Panax quinquefolium for 8 weeks. The crude saponins inhibited pancreatic lipase activity in vitro. Furthermore, crude saponins (lg/kg body weight) inhibited the elevations of plasma triacylglycerol in rats administered the oral lipid emulsion tolerance test. In addition, long-term administration of crude saponins, the parametrial adipose tissue weight was decreased by feeding a high-fat diet containing l% or 3% crude saponins compared to those of high-fat diet group. It is demonstrated that the anti-obesity effects of the crude saponins from stems and leaves of Panax quinquefolium in high-fat diet-treated mice may be due to the inhibition of intestinal absorption of dietary fat by ginsenosides Rc, Rb(1) and Rb(2).

Hypoglycemic effect of protopanaxadiol-type ginsenosides and compound K on Type 2 diabetes mice induced by high-fat diet combining with streptozotocin via suppression of hepatic gluconeogenesis.

Compound K (CK) is a final intestinal metabolite of protopanaxadiol-type ginsenosides (PDG) from Panax ginseng. Although anti-diabetic activity of CK have been reported with genetic mouse models (db/db mice) in recent years, the therapeutic usefulness of CK and PDG in type 2 diabetes, a more prevalent form of diabetes, remains unclear. In the present investigation, we developed a mouse of non-insulin-dependent diabetes mellitus that closely simulated the metabolic abnormalities of the human disease. For this purpose, type 2 diabetes was induced in male ICR mice by combining of streptozotocin. The male ICR mice fed with HFD for 4 weeks received 100mg/kg of STZ injected intraperitoneally. After 4 weeks, mice with fasting (12h) blood glucose levels (FBG) above 7.8 mmol/L were divided into 3 groups (n=12) and treated with vehicle (diabetes model, DM), 300 mg/kg/day of PDG and 30 mg/kg/day of CK for 4 weeks while continuing on the high-fat diet. Hypoglycemic effects of CK and PDG were consistently demonstrated by FBG levels, and insulin-sensitizing effects were seen during oral glucose tolerance testing (OGTT). Moreover, the mechanism of hypoglycemic effect in type 2 diabetic mice was examined. Gluconeogenic genes, Phosphoenolpyruvate carboxykinase (PEPCK) and Glucose-6-phosphatase (G6Pase), were decreased in two treatment groups with CK showing greater effects. These findings demonstrated the hypoglycemic and insulin-sensitizing capabilities of CK on type 2 diabetes induced by HFD/STZ via down-regulation of PEPCK and G6Pase expression in liver.

Natural medicines for alcoholism treatment: a review

Alcoholism is a serious problem throughout the world. The development of alcoholism remedies have medical, social and economical significance. In view of the pitfalls of psychological dependence and adverse behavioural effects of synthetic drugs, the development of low toxicity and high efficiency medicines derived from natural products exhibits expansive market prospects. Based on these considerations, we summarize briefly folk application of traditional hangover remedies and clinical application of herbal complex and patent medicines for alcoholism treatment. We have reviewed the effects of natural medicines on intake, absorption and metabolism of alcohol, as well as the protective effects on alcohol-induced acute and chronic tissue injury.

Anti-Obesity effects of protopanaxdiol types of Ginsenosides isolated from the leaves of American ginseng (Panax quinquefolius L.) in mice fed with a high-fat diet.

Effects of protopanaxdiol (PDG) and protopanaxatriol (PTG) types of ginsenosides isolated from the leaves of American ginseng on porcine pancreatic lipase activity were determined in vitro. PDG inhibited the pancreatic lipase activity in a dose-dependent manner at the concentrations of 0.25-1mg/ml. It inhibited hydrolysis of about 83.2% of triolein at about 1mg/ml of PDG. However, PTG showed no inhibitory activity. Therefore, anti-obesity activity of PDG was evaluated in mice fed a high-fat diet. The results demonstrated that PDG was effective in preventing and healing obesity, fatty liver and hypertriglyceridemia in mice fed with a high-fat diet.

Application of response surface methodology to optimise ultrasonic-assisted extraction of four chromones in Radix Saposhnikoviae.

INTRODUCTION Radix Saposhnikoviae is one of the most famous Chinese herbal medicines with many pharmacological activities towards inflammatory symptoms and antioxidation. Chromones are considered as one of the effective components. It is important to find a reasonable method to extract the chromones in S. divaricata. OBJECTIVE To develop an ultrasonic-assisted extraction (UAE) to extract chromones in Radix Saposhnikoviae and to optimise extraction conditions. METHODOLOGY Four chromones (prim-O-glucosylcimifugin, cimifugin, 5-O-methylvisammioside and sec-O-glucosylhamaudol) were extracted by the UAE method combined with response surface methodology (RSM). Box-Behnken design (BBD) was applied to evaluate the effects of three independent variables (ethanol concentration, extraction time and extraction temperature) on the chromones yield of Radix Saposhnikoviae. RESULTS Correlation analysis of the mathematical-regression model indicated that a quadratic polynomial model could be employed to optimise the extraction of chromones by UAE method. The optimal conditions to obtain the highest chromones yield of Radix Saposhnikoviae were a solvent of 75% ethanol, an extraction time of 48 min and an extraction temperature of 67°C. CONCLUSION Under these optimal conditions, the experimental values agreed closely with the predicted values. The analysis of variance indicated a high goodness of model fit and the success of RSM method for optimising chromones extraction in Radix Saposhnikoviae.

A method of extracting ginsenosides from Panax ginseng by pulsed electric field

The objective of this study was to develop and optimize a pulsed electric field (PEF) extraction method. Various experimental conditions, including electric field intensity and frequency, were evaluated against extraction methods. The content of six major ginsenosides (Rg(1), Re, Rb(1), Rc, Rb(2), and Rd) were quantified by HPLC. The results indicated that the highest yield of the ginsenoside is 12.69 mg/g by PEF using the conditions of 20 kV/cm electric field intensity, 6000 Hz frequency, 70% ethanol-water solution, and 150 L/h velocity. The yield of the ginsenoside of PEF extraction method is higher than the other five methods, such as microwave-assisted extraction, heat reflux extraction, ultrasonic-assisted extraction, accelerated solvent extraction, and ultrahigh pressure extraction, The whole extraction process of PEF takes less than 1 s, which is much less than the heat reflux extraction method for 6 h and even newly used technique ultrahigh pressure extraction method of 2 min. The high efficiency, shorter extraction times, and lower energy cost of PEF extraction method can be applied in the industrial production of saponins from Panax ginseng. The PEF extraction method is a promising and constructive method to extract ginsenosides.

Absorption mechanism of ginsenoside compound K and its butyl and octyl ester prodrugs in Caco-2 cells.

Ginsenoside compound K (CK) is a bioactive compound with poor oral bioavailability due to its high polarity, while its novel ester prodrugs, the butyl and octyl ester (CK-B and CK-O), are more lipophilic than the original drug and have an excellent bioavailability. The aim of this study was to examine the transport mechanisms of CK, CK-B, and CK-O using human Caco-2 cells. Results showed that CK had a low permeability coefficient (8.65 × 10(-7) cm/s) for apical-to-basolated (AP-BL) transport at 10-50 μM, while the transport rate for AP to BL flux of CK-B (2.97 × 10(-6) cm/s) and CK-O (2.84 × 10(-6) cm/s) was significantly greater than that of CK. Furthermore, the major transport mechanism of CK was found as passive transcellular diffusion with active efflux mediated by P-glycoprotein (P-gp). In addition, it was found that CK-B and CK-O were not the substrate of efflux transporter since the selective inhibitors (verapamil and MK-571) of efflux transporter had little effects on the transport of CK-B and CK-O in the Caco-2 cells. These results suggest that improving the lipophilicity of CK by acylation can significantly improve the transport across Caco-2 cells.

Pressurized liquid extraction followed by LC‐ESI/MS for analysis of four chromones in Radix Saposhnikoviae

An efficient pressurized liquid extraction (PLE) technique was employed in extracting chromones from the roots of Saposhnikovia divaricata (Radix Saposhnikoviae). Chromones were quantified and analyzed by LC-ESI/MS. The PLE procedure was optimized, validated and compared with the other conventional extraction techniques. PLE gained the best result due to the highest extraction efficiency within the shortest extraction time. The optimal conditions of PLE were employing 50% ethanol as the extraction solvent at a temperature of 140°C and an extraction pressure of 1500 psi, using one extraction cycle with a static extraction time of 8 min. A good LC separation was achieved using a Hypersil ODS2 column and methanol/water as the mobile phase at a flow rate of 0.8 mL/min. MS coupling with an ESI interface in the positive ion mode was used as the detection technique. This is the first report on combining PLE with LC-ESI/MS for the extraction and quantification of chromones in Radix Saposhnikoviae. The elaborated PLE method also provided a good alternative for the chromone extraction from other plant substances.

Application of accelerated solvent extraction to the investigation of saikosaponins from the roots of Bupleurum falcatum.

Accelerated solvent extraction (ASE) was applied to the extraction of saikosaponin a, saikosaponin c and saikosaponin d from the roots of Bupleurum falcatum. Main extraction parameters such as the extraction solvents, extraction temperature and static extraction time were investigated and optimized. The optimized procedure employed 70% methanol as extraction solvent, 120 degrees C of extraction temperature, 10 min of static extraction time, 60% of flush volume and the extraction recoveries of the three compounds were near to 100% with one extraction cycle. The extracted samples were analyzed by HPLC with UV detector. The HPLC conditions were as follows: Hypersil ODS2 (4.6 mmx250 mm, 5 microm) column, acetonitrile and water as mobile phase, flow rate of 1.0 mL/min, UV detection wavelength of 204 nm and injection volume of 20 microL. Compared with the traditional methods including heat-reflux extraction and ultrasonic-assisted extraction, the proposed ASE method was more efficient and faster to be operated. The results indicated that ASE was an alternative method for extracting saikosaponins from the roots of B. falcatum.