Effects of the purified extracts from Lycii Cortex Radicis and ginger on lipid statusand serum cytokine levels in rats fed high fat diet

The present study was to investigate the effects of Lycii Cortex Radicis (LCR), the root bark of lycium (Lycium chenese Miller) and ginger (Gin) on body lipid status and serum levels of cytokines. Sprague-Dawley (SD) male rats weighing 193.6 +/- 16.8 g were divided into five groups, including one low fat (LF) and four high fat groups, i.e. HF-Control, HF-LCR, HF-Gin and HF-LCR + Gin groups. Diets for HF-LCR, HF-Gin and HF-LCR + Gin groups contained purified extracts having 0.2 g LCR tyramine, ginerol and 0.1 g tyramine plus 0.02 g gingerol per kg, respectively. Compared with those of the HF-Control total serum cholesterol level decreased, and HDL-cholesterol level increased in the HF-LCR group and serum triglyceride levels decreased in the three experimental groups fed the purified extracts. Liver cholesterol level was lower in the HF-LCR group than the HF-Control group, but triglyceride levels, which were increased by high fat diets were not changed by significantly by LCR or ginger extracts. Fecal lipid excretion was higher in the HF-LCR and HF-Gin groups, but cholesterol excretion was lower in the HF-Gin group than in the HF-Control group. The activities of liver cytosolic glucose-6-phosphate dehydrogenase and malic enzyme were lower in the HF-LCR + Gin group than in the HF-Control group. Serum adiponectin levels did not differ among the five groups, while leptin level was lower in the HF-Gin group and C-reactive protein levels were lower in the HF-Gin and the HF-LCR + Gin groups than in the HF-Control group. It is concluded that LCR can be utilized as an ingredient for lipid-lowering functional foods in the form of purified extract and addition of small amount of ginger extract would be useful for reducing one of the inflammatory cytokines to help prevent atherosclerosis.

Study on the hypochlolesterolemic and antioxidative effects of tyramine derivatives from the root bark of Lycium chenese Miller

The aim of the present study was to investigate the hypocholesterolemic effect and potential of tyramine derivatives from Lycii Cortex Radicis (LCR), the root bark of lycium (Lycium chenese Miller) in reducing lipid peroxidation. The activities of enzymes, hepatic 3-hydroxy 3-methylglutaryl (HMG) CoA reductase and acyl-CoA:cholesterol acyltransferase (ACAT) and LDL oxidation were measured in vitro and animal experiments were also performed by feeding LCR extracts to rats. The test compounds employed for in vitro study were trans-N-p-coumaroyltyramine (CT) and trans-N-feruloyltyramine (FT), LCR components, N-(p-coumaroyl)serotonin (CS) and N-feruloylserotonin (FS) from safflower seeds, ferulic acid (FA) and 10-gingerol. It was observed that FT and FS at the concentration of 1.2 mg/mL inhibited liver microsomal HMG CoA reductase activity by ~40%, but no inhibition of activity was seen in the cases of CT, CS, FA and 10-gingerol. Whereas, ACAT activity was inhibited ~50% by FT and CT, 34-43% by FS and CS and ~80% by 10-gingerol at the concentration of 1 mg/mL. A significant delay in LDL oxidation was induced by CT, FT, and 10-gingerol. For the animal experiment, five groups of Sprague-Dawley male rats were fed high fat diets containing no test material (HF-control), 1 and 2% of LCR ethanol extract (LCR1 and LCR2), and 1% of extracts from safflower seed (Saf) and ginger (Gin). The results indicated that total cholesterol level was significantly lower in Saf, LCR2 and Gin groups, and HDL cholesterol level was lower only in Gin group when compared with HF-control group; while there was no difference in the serum triglyceride levels among the five experimental groups. The level of liver cholesterol was significantly lower in LCR1 and LCR2 groups than HF-control. Serum levels of TBARS were significantly lower only in LCR2 group when compared with HF-control group. From the observed results, we concluded that LCR can be utilized as a hypocholesterolemic ingredient in combination with ginger, especially for functional foods.