Objective:To investigate the effect of dietary cholesterol on hepatic TG accumulation in rats. Method:Fourteen male Wistar rats were randomly divided into 2 groups and fed 1% cholesterol or cholesterol free AIN76 diets. After 4 w,serum triglyceride(TG) ,total cholesterol(TC) ,high density lipoprotein cholesterol(HDL-C) ,phospholipids(PL) ,glucose and free fatty acid(NEFA) levels were determined. Hepatic lipid concentrations(TG,TC,PL) and the activities and/or mRNA expression of malic enzyme(ME) ,glucose-6-phosphate dehydrogenase(G6PDH) ,fatty acid synthase(FAS) ,phosphatidate phophatase(PAP) ,carnitine palmitoyl transferase(CPT1,2) ,HMG-CoA reductase,acylCoA-cholesterol acyltransferase(ACAT) ,cholesterol 7?-hydroxylase(CYP7A) were also determined. Results:The serum TC and non-HDL-C levels were significantly increased but TG and HDL-C levels were significantly decreased by cholesterol feeding. The concentrations of hepatic TC and TG were 4-20 folds higher in cholesterol group than those in cholesterol free group. The activities of hepatic ME,G6PDH,FAS,PAP and CPT were depressed by cholesterol(40%,70%,50%,15% and 25% respectively) . The mRNA expression of FAS,CPT1,CPT2,and HMG-CoA reductase were down-regulated(35%,30%,50% and 25% respectively) and CYP7? and ACAT were up regulated(6.5 and 1.6 fold) by cholesterol in liver. Conclusion:The dietary cholesterol increases TG accumulation in liver,but dose not stimulates the activity and the gene expressionof hepatic TG synthesis related enzymes.

The present study reported the effect of two male antifertility agents gossypol acetic acid and GTW on DNA of C3H10T1/2 mouse fibroblasts. Our results showed that the cells treated with gossypol or GTW at high concentration (2-3 ?g/ml) for 4 hours, show silver grains in their nuclei as much as the positive control group, N-methyl N′-nitro-N-nitrosoguanidine (MNNG) a known carcinogen. However, if the agents were used at moderate concentrations (0.5-1?g/ml), the silver grains were much less, if the concentrations of gossypol or GTW were of 0.1-0.3 ?g/ml, the silver grains were as less as the control group. In a colony-forming test, we found that the cells lost their proliferate ability, since no colonies could be formed, if gossypol or GTW were of high concentration; while at moderate or low concentrations, the colony-forming rate was as high as 8.1-10.5％. Taking all of these results into consideration, we suggest that high concentrations of gossypol or GTW can damage cell DNA severely, moderate concentration of the agents break cell DNA to a certain extent, but the cells can repair, while low concentration of gossypol or GTW exert no obvious effect on cells. The significance of these observations was briefly discussed.

The glycosaminoglycan (GAG), isolated from Bay scallop Argopectenirradians, contains neutral monosaccharides besides hexosamines and hexosuronic acids. The monosaccharides obtained by alcoholysis with HCI-methylalcohol from the sample of GAG was trimethylsilanized with hexamethyldisilan and chlortrimethylsilan (HMDS ' TMCS = 2 : 1). And the trimethylsilyl derivatives of monosaccharides was determined by gas chro-matography. Compared the gas chromatography of the sample with that of standard monosaccharides, it was found that the GAG of the Bay scallop contains five neutral monosaccharides, viz glucose, galactose, xylose, fucose and rhamnose.

Objective To investigate the effects of the two major conjugated linoleic acid(CLA) isomers on serum lipoprotein composition in fatty rats.Method Eighteen male OLETF rats were randomly divided into three groups.The control group fed with AIN76 diets,CLA groups were fed with 1% 9c,11t-CLA (9ct group) or 1%10t,12c-CLA (10tc group) containted AIN76 diets.After two weeks,serum triglyceride (TG),total cholesterol (TC),and high density lipoprotein cholesterol (HDL-c) were determined by commercial kits.On the other hand,serum lipoprotein were separated into chylomicron(CM),very low density lipoprotein(VLDL),low density lipoprotein(LDL) and HDL by HPLC according to the different particle sizes,and the TC and TG levels were measured in each lipoprotein.Results 10t,12c-CLA feeding reduced the concentrations of rat serum TG significantly,and increased the concentration of serum TC (26.1%) by increasing TC levels of the small particle size LDL and the big particle size HDL.While 9c,11t-CLA feeding increased the serum TG by 22.6%,and had no effect on the serum TC.Conclusion 10t,12c-CLA can reduce the concentration of serum TG and increase the concentration of HDL-c,but the effect on the improvement of atherosclerosis still need further investigation.

Objective: To study the antioxidative and hepatoprotective activities of low molecular fucoidan oligosaccharides(LMFO) from Laminaria japonica in mice.Methods: Mice were pretreated with LMFO(50?100?150 mg/kg ig respectively, 10 days),and then 0.2 % CCl 4 10 ml/kg ig and D-GalN(600 mg/kg)+LPS(lipopolysaccharide,1 ?g/kg) ig respectively in two model groups to induce liver injury. Liver injury was assessed by quantifying activities of plasma GPT, SOD, GSH-Px and MDA content.Results: The increase of plasma GPT activity was significantly inhibited by LMFO in two liver injury models, suggesting that LMFO had good protective effect on the hepatocytes. LMFO had good antioxidative effect in mice with liver injury induced by CCl 4 and D-GalN+LPS as indicated by decreased MDA content and increased activities of plasma SOD and GSH-Px. Conclusion: LMFO is protective against CCl 4-induced and D-GalN+ LPS induced liver injury in mice and its effect may be due to its antioxidative activities in vivo.

Objective:To study the effects of different molecular weight of collagen polypeptides from Apostichopus japonicus (A1:6 000U

10000 u,SP2:6 000 u0.05),the melanogenesis and tyrosinase activity were inhibited remarkably(P

Objective To investigate the mechanism of orotic acid-induced fatty liver in rats. Method Rats were randomly divided into 2 groups,and fed AIN93 diet with or without 1% orotic acid (OA) for 10d. Serum total cholesterol (TC),triglyceride (TG),high density lipoprotein-cholesterol (HDL-C),hepatic lipids concentrations (TG,TC and phospholipids),hepatic enzymes activities and mRNA levels of key enzymes related to lipids metabolism,as well as hepatic genes expression of transcription factors were determined. Results OA administration significantly increased serum and hepatic TG concentration. The activity and mRNA level of fatty acid synthase (FAS) were obviously up-regulated by OA treatment,whereas the activities and mRNA concentrations of carnitin palmitoyl transferase (CPT) and microsomal triglyceride transfer protein (MTP) were depressed significantly. Furthermore,OA also stimulated the mRNA expression of sterol regulatory element binding protein-1c (SREBP-1c),but did not alter the mRNA concentrations of peroxisome proliferator-activated receptor alpha (PPAR?) in liver. Conclusion:The stimulation of TG synthesis caused by enhancement of SREBP-1c and its target genes-FAS,which could be responsible for development of fatty liver. On the other hand,the inhibition of fatty acid beta-oxidation and VLDL secretion were related to the observed lipids accumulation.

Objective To establish a method for determination of trace lead in alginate sodium.Method The lead in the samples was determined by fluorescence spectroscopy after been digested by hydrothermal decomposition.Results The detection limit of lead was 2.71?10-2?g?mL-1.The relative standard deviation of the three samples were 4.06%,1.57% and 2.12% respectively,the average recovery was 88.32%～100.8%.Conclusion The method had the advantages of simple operation,higher precision,higher sensitivity and repeatability and was suitable for the determination of trace lead in the alginate sodium