Effect of fermented Angelicae gigantis Radix on carbon tetrachloride-induced hepatotoxicity and oxidative stress in rats.

This study is aimed to evaluate the protective effect of fermented Angelicae gigantis Radix (AGR) with Monascus purpureus strain on carbon tetrachloride (CCl(4))-induced hepatotoxicity and oxidative stress in rats. The activities of liver marker enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and the levels of lipid peroxidation were increased when CCl(4) was treated but these parameters were significantly decreased by fermented AGR treatment. CCl(4) treatment exhibited decrease in serum concentrations of triglyceride, total cholesterol, HDL-cholesterol, and free fatty acids, and these were also decreased by fermented AGR administration. The level of serum leptin was significantly lower in fermented AGR administration than that in normal control group. CCl(4) treatment significantly increased the concentration of liver triglyceride. The current study observed significant elevations of the thiobarbituric acid-reactive substances (TBARS) levels in the liver homogenate, mitochondrial, and microsomal fractions of CCl(4) control group compared with normal control group. CCl(4) treatment resulted in a significant decrease in the levels of plasma and hepatic glutathione, but these reductions were significantly increased by fermented AGR administration. CCl(4) induced the marked hepatocytes necrosis and fatty accumulation around the central veins. Accordingly, fermented AGR may be an ideal candidate for the hepatoprotective effect in animal model.

Antioxidant effects of fermented sea tangle (Laminaria japonica) by Lactobacillus brevis BJ20 in individuals with high level of γ-GT: A randomized, double-blind, and placebo-controlled clinical study.

A randomized, double-blind, and placebo-controlled clinical study was performed to evaluate the antioxidant effects of fermented sea tangle (FST) on healthy volunteers with high levels of γ-glutamyltransferse (γ-GT). Forty-eight participants were divided into a placebo group and an FST group that received FST (1.5 g/day) for 4 weeks. Serum γ-GT, malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities were determined before and after the trial. Administering FST significantly decreased serum levels of γ-GT and MDA. Additionally, SOD and CAT activities were significantly augmented compared to those in the placebo group after 4 weeks, but no significant alteration was observed in GPx activity compared to that in the placebo group. Our findings indicate that FST enhanced the antioxidant defense system in a healthy population and may be useful as a functional food ingredient.

Effect of betaine on the hepatic damage from orotic acid-induced fatty liver development in rats.

Betaine prevents hepatic damage caused by ethanol and carbone tetrachloride (CCl4) in rats. Present study was to investigate the effect of betaine on the hepatic microsomal triglyceride transfer protein (MTP) mRNA expression in orotic acid (OA)-induced fatty liver in rats. OA feeding was attributed to the significant increase in the hepatic levels of triglyceride and the serum levels of ALT and AST and resulted in typical histology of fatty liver contained numerous largely fat droplets. While concomitant supplementation of betaine to OA diet was slightly reduced the hepatic triglyceride concentrations and was significantly decreased ALT activity. Hepatic MTP mRNA expression by OA treatment increased by 14% despite triglyceride accumulation in the liver in OA treatment rats relative to rats fed a normal diet without OA supplemented, but MTP expression by simultaneous supplementation of OA and betaine was slightly decreased by 7.9% as compared to the OA-feeding rats. A significant elevation of TBARS contents in the liver homogenate, microsome, and mitochondrial fractions of the OA-feeding rats compared with the normal rats, however, these increases were significantly or slightly decreased by simultaneous addition of OA and betaine. The increases of hepatic OA and betaine levels in OA feeding rats was also found when compared to the normal rats, but these increases were significantly lowered in the concomitant supplementation OA and betaine. The content of Fe was significantly increased in the OA feeding rats, but this elevation showed significantly recovered as low as the normal level by concomitant with OA and betaine. Zinc content was also significantly decreased in the OA feeding rats compared with the normal rats, but this reduction was more significantly elevated by concomitant with OA and betaine. Hepatic glutathione content in the OA feeding rats was similar to that of the normal rats, but this content was slightly reduced without statistically significant differences. But, a significant elevation in the hepatic glutathione content was found in the simultaneously administration OA and betaine. The hepatocytes contained numerous largely fat droplets induced by OA administration and was slightly reduced by simultaneous supplementation of OA and betaine. Present study demonstrated that betaine has a weak preventive action on the OA-induced triglyceride accumulation.

Effect of fermented sea tangle on the alcohol dehydrogenase and acetaldehyde dehydrogenase in Saccharomyces cerevisiae.

Sea tangle, a kind of brown seaweed, was fermented with Lactobacillus brevis BJ-20. The gamma-aminobutyric acid (GABA) content in fermented sea tangle (FST) was 5.56% (w/w) and GABA in total free amino acid of FST was 49.5%. The effect of FST on the enzyme activities and mRNA protein expression of alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) involved in alcohol metabolism in Saccharomyces cerevisiae was investigated. Yeast was cultured in YPD medium supplemented with different concentrations of FST powder [0, 0.4, 0.8, and 1.0% (w/v)] for 18 h. FST had no cytotoxic effect on the yeast growth. The highest activities and protein expressions of ADH and ALDH from the cell-free extracts of S. cerevisiae were evident with the 0.4% and 0.8% (w/v) FST-supplemented concentrations, respectively. The highest concentrations of GABA as well as minerals (Zn, Ca, and Mg) were found in the cell-free extracts of S. cerevisiae cultured in medium supplemented with 0.4% (w/v) FST. The levels of GABA, Zn, Ca, and Mg in S. cerevisiae were strongly correlated with the enzyme activities of ADH and ALDH in yeast. These results indicate that FST can enhance the enzyme activities and protein expression of ADH and ALDH in S. cerevisiae.

Fermented Viola mandshurica inhibits melanogenesis in B16 melanoma cells.

We assessed the effects of chloroform extract of fermented Viola mandshurica (CEFV) on melanogenesis B16 melanoma cells. CEFV treatment significantly decreased melanin content and tyrosinase activity in dose-dependent manners. To elucidate the mechanism of the inhibitory effects of CEFV on melanogenesis, we performed RT-PCR and Western blotting for melanogenesis-related genes such as tyrosinase, tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF). CEFV strongly inhibited mRNA as well as the protein expression of tyrosinase and MITF, but had no significant effect on TRP-1 or TRP-2 expressions. It markedly decreased the phosphorylation of cAMP responsive element binding protein (CREB), and induced the duration of extracellular signal-regulated kinase (ERK) activation, leading to reduction of MITF expression and subsequently that of tyrosinase. Therefore, we suggest that CEFV induces downregulation of melanogenesis through decreased CREB phosphorylation and ERK activation.

Antihyperglycemic effect of stem bark powder from paper mulberry (Broussonetia kazinoki Sieb.) in type 2 diabetic Otsuka Long-Evans Tokushima fatty rats.

The effect of stem bark powder from paper mulberry (PMSB) on serum glucose, insulin, fructosamine, and lipid concentrations, as well as enzyme activities that serve as liver injury markers, was investigated in genetically diabetic Otsuka Long-Evans Tokushima fatty (OLETF) rats. Both nondiabetic Long-Evans Tokushima Otsuka (LETO) rats and diabetic OLETF rats (30 weeks old) were fed a semisynthetic diet with or without 50 g/kg PMSB for 8 weeks and then compared. The OLETF control rats showed a high amount of daily water intake in comparison to those in the LETO group. The concentrations of glucose, fructosamine, total lipid, triglyceride, total cholesterol, and high-density lipoprotein-cholesterol and the activities of aspartate aminotransferase and alanine aminotransferase (ALT) in serum were higher in the OLETF control rats than those in the LETO control rats. However, PMSB ingestion decreased the serum levels of glucose, fructosamine, triglyceride, and total cholesterol and the activity of ALT in the OLETF rats, but not in the LETO rats. The concentration of serum insulin was also significantly increased by PMSB consumption in the OLETF rats compared to the OLETF control rats. These results suggest that PMSB might have an antihyperglycemic effect in the OLETF rat and that the increased blood insulin level would be an important regulatory factor for improving hyperglycemia in the current animal model.

Dietary phosphatidylcholine alleviates fatty liver induced by orotic acid.

OBJECTIVE: We compared the effect of dietary phosphatidylcholine (PC) with that of triacylglycerol (TG), both with the same fatty acid profiles, on fatty infiltration in orotic acid (OA)-induced fatty liver of Sprague-Dawley rats. METHODS: Rats were fed an OA-supplemented diets containing TG (TG+OA group) or PC (20% of dietary lipid, PC+OA group) for 10 d. Rats fed the TG diet without OA supplementation served as the basal group. RESULTS: Administering OA significantly increased the weights and TG accumulation in livers of the TG+OA group compared with the basal group. These changes were attributed to significant increases in the activities of fatty acid synthase, malic enzyme, and glucose-6-phosphate dehydrogenase, which are fatty acid synthetic enzymes, and phosphatidate phosphohydrolase, a rate-limiting enzyme of TG synthesis. However, the PC+OA group did not show TG accumulation and OA-induced increases of these enzyme activities. Further, a significant increase in the activity of carnitine palmitoyl transferase, a rate-limiting enzyme of fatty acid beta-oxidation, was found in the PC+OA group. CONCLUSIONS: Dietary PC appears to alleviate the OA-induced hepatic steatosis and hepatomegaly, mainly through the attenuation of hepatic TG synthesis and enhancement of fatty acid beta-oxidation in Sprague-Dawley rats.

Alleviation of fatty liver by alpha-linolenic acid.

We compared the efficacy of alpha-linolenic acid (alpha-LNA, n-3) and linoleic acid (LA, n-6) on orotic acid (OA)-induced fatty liver in Sprague-Dawley rats. Rats were fed semi-synthetic diets containing either LA or alpha-LNA with or without 1% OA for 2 wk. OA supplementation lowered serum lipids in LA+OA groups. In addition to the decline of serum lipids in alpha-LNA groups compared to LA groups, a further decrease was found in alpha-LNA+OA groups compared to LA+OA groups. OA-containing diets significantly increased the liver weights and triacylglycerol (TG) accumulations compared with the OA-free diets. These results were attributed to the significant increases in the activities of phosphatidate phosphohydrolase (PAP), a rate-limiting enzyme of TG synthesis, and glucose-6-phosphate dehydrogenase, a fatty acid synthesis-related enzyme. However, the increase of PAP activity was significantly less in the alpha-LNA+OA group as compared with the LA+OA group. These results suggest that dietary alpha-LNA alleviates OA-induced hepatic TG accumulation through the attenuation of hepatic TG synthesis in rats.

Diol- and triol-type ginseng saponins potentiate the apoptosis of NIH3T3 cells exposed to methyl methanesulfonate.

In this study we investigated the effect of ginseng saponins on the p53-dependent apoptosis in NIH3T3 cells exposed to methyl methanesulfonate (MMS), an alkylating agent. Trypan blue exclusion assay, cell morphology studies, and apoptotic index determined by acridine orange staining showed that the postincubation of MMS-exposed cells in medium containing diol- (PD) or triol-type (PT) ginseng saponins potentiate the apoptotic cell death. FACS analysis indicated that the increased apoptotic cell population in the saponin-postincubation group was accompanied by the accumulation of cells in G0/G1 phase. By Western blot analyses it was demonstrated that postincubation of saponins increases the expression of p53 and p21 in MMS-exposed cells but decreased that of CDK2, cyclin E and D1, and PCNA. The upregulation of p53 and p21 and downregulation of CDK2 was shown to be p53-dependent in experiments using the p53 antisense oligonucleotide. These results suggest that ginseng saponins contain components potentiating the apoptosis of MMS-exposed NIH3T3 cells via p53 and p21 activation, accompanied with by downregulation of cell cycle-related protein expression.