Antioxidant and hepatoprotective effects of Korean ginseng extract GS-KG9 in a D-galactosamine-induced liver damage animal model

BACKGROUND/OBJECTIVES@#This study was designed to investigate the improvement effect of white ginseng extract (GS-KG9) on D-galactosamine (Ga1N)-induced oxidative stress and liver injury. @*SUBJECTS/METHODS@#Sixty Sprague-Dawley rats were divided into 6 groups. Rats were orally administrated with GS-KG9 (300, 500, or 700 mg/kg) or silymarin (25 mg/kg) for 2 weeks. The rats of the GS-KG9- and silymarin-treated groups and a control group were then intraperitoneally injected Ga1N at a concentration of 650 mg/kg for 4 days. To investigate the protective effect of GS-KG9 against GalN-induced liver injury, blood liver function indicators, anti-oxidative stress indicators, and histopathological features were analyzed. @*RESULTS@#Serum biochemical analysis indicated that GS-KG9 ameliorated the elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) in GalN-treated rats. The hepatoprotective effects of GS-KG9 involved enhancing components of the hepatic antioxidant defense system, including glutathione, glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). In addition, GS-KG9 treatment inhibited reactive oxygen species (ROS) production induced by GalN treatment in hepatocytes and significantly increased the expression levels of nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) proteins, which are antioxidant proteins. In particular, by histological analyses bases on hematoxylin and eosin, Masson's trichrome, α-smooth muscle actin, and transforming growth factor-β1 staining, we determined that the administration of 500 mg/kg GS-KG9 inhibited hepatic inflammation and fibrosis due to the excessive accumulation of collagen. @*CONCLUSIONS@#These findings demonstrate that GS-KG9 improves GalN-induced liver inflammation, necrosis, and fibrosis by attenuating oxidative stress. Therefore, GS-KG9 may be considered a useful candidate in the development of a natural preventive agent against liver injury.

Differential Effects of Quercetin and Quercetin Glycosides on Human α7 Nicotinic Acetylcholine Receptor-Mediated Ion Currents

Quercetin is a flavonoid usually found in fruits and vegetables. Aside from its antioxidative effects, quercetin, like other flavonoids, has a various neuropharmacological actions. Quercetin-3-O-rhamnoside (Rham1), quercetin-3-O-rutinoside (Rutin), and quercetin-3-(2(G)-rhamnosylrutinoside (Rham2) are mono-, di-, and tri-glycosylated forms of quercetin, respectively. In a previous study, we showed that quercetin can enhance α7 nicotinic acetylcholine receptor (α7 nAChR)-mediated ion currents. However, the role of the carbohydrates attached to quercetin in the regulation of α7 nAChR channel activity has not been determined. In the present study, we investigated the effects of quercetin glycosides on the acetylcholine induced peak inward current (I(ACh)) in Xenopus oocytes expressing the α7 nAChR. I(ACh) was measured with a two-electrode voltage clamp technique. In oocytes injected with α7 nAChR copy RNA, quercetin enhanced I(ACh), whereas quercetin glycosides inhibited I(ACh). Quercetin glycosides mediated an inhibition of I(ACh), which increased when they were pre-applied and the inhibitory effects were concentration dependent. The order of I(ACh) inhibition by quercetin glycosides was Rutin≥Rham1>Rham2. Quercetin glycosides-mediated I(ACh) enhancement was not affected by ACh concentration and appeared voltage-independent. Furthermore, quercetin-mediated I(ACh) inhibition can be attenuated when quercetin is co-applied with Rham1 and Rutin, indicating that quercetin glycosides could interfere with quercetin-mediated α7 nAChR regulation and that the number of carbohydrates in the quercetin glycoside plays a key role in the interruption of quercetin action. These results show that quercetin and quercetin glycosides regulate the α7 nAChR in a differential manner.

Ginsenoside Re Enriched Fraction (GS-F3K1) from Ginseng Berries Ameliorates Ethanol-Induced Erectile Dysfunction via Nitric Oxide-cGMP Pathway

Erectile dysfunction (ED) is a highly prevalent disorder that affects millions of men and considered to be an early symptom of atherosclerosis and a precursor of various systemic vascular disorders. The aim of the present study was to prepare ginsenoside Re enriched fraction (GS-F3K1, ginsenoside Re 10%, w/w) from ginseng berries flesh and to investigate the enhanced activities of GS-F3K1 on alcohol-induced ED. GS-F3K1 was prepared by the continuous liquid and solid separating centrifugation and circulatory ultrafiltration from ginseng berries flesh. GS-F3K1 was administered for 5 weeks in ethanol-induced ED rat by oral administration of 20% ethanol. To investigate the effects of GS-F3K1 on ED model, the levels of nitrite expression, cyclic guanosine monophosphate (cGMP) and erectile response of the penile corpus cavernosum of rat were measured. The erectile response of the corpus cavernosum was restored after GS-F3K1 administration, to a level similar to the normal group. The level of nitrite and cGMP expression in the corpus cavernosum of GS-F3K1-administered male rats was increased significantly compared to positive control group. GS-F3K1 from ginseng berries should effectively restore ethanol-induced ED in male rats and could be developed as a new functional food for the elderly men.

Anti-oxidant and Hepatoprotective Effect of White Ginsengs in H2O2-Treated HepG2 Cells

The antioxidant activity of white ginseng was not recorded in Korea Functional Food Code, while its activity of red ginsengs was recorded. The aim of this study was to evaluate the antioxidant and hepato protective effect of different ginsengs in H2O2-treated HepG2 cells. White and red ginseng were prepared from longitudinal section of the same fresh ginseng (4-year old). The whole parts of white and red ginsengs were separately extracted with 70% ethanol and distilled water respectively, at 70 degrees C to obtain therapeutic ginseng extracts namely, WDH (distilled water extract of white ginseng), WEH (70% ethanol extract of white ginseng), RDH (distilled water extract of red ginseng) and REH (70% ethanol extract of red ginseng). In this work, we have investigated the DPPH, hydroxyl radical, Fe2+-chelating activity, intracellular ROS scavenging capacity and lipid peroxidation of different ginsengs. All these extracts showed a dose dependent free-radical scavenging capacity and a ROS generation as well as lipid peroxidation was significantly reduced by treatment with bioactive extracts of white ginsengs (WDH) than red ginsengs. Additionally, white ginseng extracts (WDH) has dramatically increased intracellular antioxidant enzyme activities like superoxide dismutase and catalase in H2O2-treated HepG2 cells. All these results explain that administration of white ginseng is useful as herbal medicine than red ginseng for chemoprevention of liver damage.

Effect of the Mixture of Pueraria lobata and Sorbus commixta Extract on the Alcohol-induced Hangover in Rats

Pueraiae Radix (PR), Pueratia Folium (PF) and Sorbus commixta (SC) mixture, namely GS-SP (PR (1)/PF (2)/SC (0.5): v/v/v) was developed as hangover-relieving elixir and its effects on alcoholic metabolism have been investigated. The enzymatic activity of alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) of GS-SP was shown higher than those of single treatment with PR, PL, SC, and the positive control group (YM-808). The survival rate of mouse liver cell line NCTC clone 1469 in the presence of acetaldehyde was 30.6, 22.2, and 8.7% at the GS-SP dosage level of 50, 100, and 200 microg/mL respectively. Different concentrations of 50, 100 and 200 mg/kg of GS-SP showed efficient activity for ADH and ALDH than YM-808 in rat fed with 25% ethanol. The levels of blood alcohol and acetaldehyde after oral administration of 200 mg/kg of GS-SP showed efficient activity of 11.7% and 37% than those of YM-808. These results have been supported to the potential for GS-SP to serve as an excellent potential in providing hangover relief and liver protection.

Effects of pectin lyase-modified red ginseng extracts in high-fat diet-fed obese mice / 한국실험동물학회지

Red ginseng and its extracts have been used as traditional medicines and functional foods in countries worldwide. The aim of this study was to examine the bioavailability of pectin lyase-modified red ginseng extracts (GS-E3D), and the effects of GS-E3D on adipogenesis of 3T3-L1 adipocytes, as well as on metabolic disorders such as hyperglycemia, dyslipidemia, and fatty liver in high-fat diet fed obese C57BL/6 mice. Mice were divided into 5 groups: normal diet group, high fat diet-vehicle group, high fat diet + 0.1 g/kg GS-E3D (0.1-GS-E3D), high fat diet + 0.3 g/kg (0.3-GS-E3D), high fat diet + 1.0 g/kg (1.0-GS-E3D). Treatment of GS-E3D reduced differentiation of 3T3-L1 adipocytes with low cytotoxicity. In the animal model, compared to the high fat diet control, serum glucose, total cholesterol, LDL-cholesterol, HDL-cholesterol, TG, and leptin level were reduced in treatment animals in a dose-dependent manner. In addition, we found that GS-E3D could decrease total hepatic lipid droplets. These results suggest that GS-E3D, as a dietary supplement, has beneficial effects on obesity and may have useful effects in health-care products.