Dong-Ryung Lee

A polymethoxy flavonoids-rich Citrus aurantium extract ameliorates ethanol-induced liver injury through modulation of AMPK and Nrf2-related signals in a binge drinking mouse model.

Nobiletin and tangeretin are polymethoxy flavonoids (PMFs), found in rich quantities in the peel of citrus fruits. In the present study, we assessed the biological effect of the PMFs on liver damage using a mouse model of binge drinking. First, we extracted PMFs from the peels of Citrus aurantium to make Citrus aurantium extract (CAE). Male C57BL/6 mice were orally treated with silymarin and CAE (50, 100, and 200 mg/kg) for 3 days prior to ethanol (5 g/kg, total of 3 doses) oral gavage. Liver injury was observed in the ethanol alone group, as evidenced by increases in serum hepatic enzymes and histopathologic alteration, as well as by hepatic oxidative status disruption. CAE improved serum marker and hepatic structure and restored oxidative status by enhancing antioxidant enzyme levels and by reducing lipid peroxidation levels. In addition, CAE evidently suppressed inflammation and apoptosis in the livers of mice administered with ethanol, by 85% (tumor necrosis factor‐α) and 44% compared to the control group, respectively. Furthermore, CAE activated lipid metabolism related signals and enhanced phosphorylation of AMP‐activated protein kinase (AMPK) and nuclear factor E2‐related factor 2 (Nrf2) with several cytoprotective proteins including heme oxygenase‐1, NAD(P)H quinone oxidoreductase 1, and γ‐glutamylcysteine synthetase. Taken together, the present study demonstrated that, CAE possesses antioxidant, anti‐inflammatory, and antiapoptotic activity against ethanol‐induced liver injury. Copyright

Hepatoprotective effects of polymethoxyflavones against acute and chronic carbon tetrachloride intoxication

In the present study, we explore the protective effects of Citrus aurantium L. extract (CAE) against acute and chronic CCl4-induced hepatotoxicity. The quantitative analysis of CAE was performed using HPLC-UV to determine the nobiletin content was approximately 27%. For the acute model, the male ICR mice were orally treated with water, silymarin (positive control, 200 mg/kg) and CAE (50 and 200 mg/kg) for 3 days prior to CCl4 (1 mL/kg, 50% v/v in olive oil) IP injection. For the chronic model (n = 6/group), the mice were treated with each treatment for 28 consecutive days and CCl4 (1 mL/kg, 20%) was injected twice a week. In both the acute and chronic models, the CCl4 alone treated group showed histopathologic alterations with a significantly increase in serum hepatic enzyme levels together with a disrupted anti-oxidative status. In contrast, the CAE treatments restored pathologic alterations and recovered the oxidative status by enhancing antioxidant enzymes and reducing lipid peroxidation levels. Furthermore, CAE enhanced nuclear factor E2-related factor 2 (Nrf2) and its related cytoprotective signals, including NAD(P)H quinone oxidoreductase 1, UDP-glucuronosyltransferase, and γ-glutamylcysteine synthetase. Taken together, the present study demonstrates that CAE exerts a protective effect against CCl4-induced hepatotoxicity with its anti-oxidant, anti-inflammatory, and anti-apoptotic activity.

Monascus pilosus-fermented black soybean inhibits lipid accumulation in adipocytes and in high-fat diet-induced obese mice

OBJECTIVE To explore the anti-obesity effects and the mechanism of action of Monascus pilosus(M. pilosus)-fermented black soybean (MFBS) extracts (MFBSE) and MFBS powders (MFBSP) in adipocytes and high-fat diet (HFD)-induced obese mice, respectively. METHODS Black soybean was fermented with M. pilosus, and the main constituents in MFBS were analyzed by HPLC analysis. In vitro, MFBSE were examined for anti-adipogenic effects using Oil-Red O staining. In vivo, mice were fed a normal-fat diet (NFD) control, HFD control or HFD containing 1 g/kg MFBSP for 12 weeks, and then body weight gain and tissues weight measured. Real-time PCR and western blot assay were used to determine the mechanism of anti-adipogenic effects. RESULTS MFBSE inhibited lipid accumulation in 3T3-L1 adipocytes without exerting cell cytotoxicity. MFBSP treatment in HFD-fed mice significantly decreased the body weight gain compared with the HFD control mice. MFBSE and MFBSP treatment resulted in significantly lower mRNA levels of adipogenesis-related genes, such as peroxisome proliferator-activated receptor γ(PPAR γ), fatty acid-binding protein 4 (FABP4), and fatty acid synthase (FAS), in adipocytes and in white adipose tissue (WAT) of HFD-induced obese mice. CONCLUSIONS These results suggest that the anti-obesity effects of MFBS are elicited by regulating the expression of adipogenesis-related genes in adipocytes and WAT of HFD-induced obese mice.

Draft Genome Sequence of Ristocetin-Producing Strain Amycolatopsis sp. Strain MJM2582 Isolated in South Korea

ABSTRACT The draft genome sequence of a ristocetin-producing Amycolatopsis strain (sp. MJM2582) isolated in South Korea is reported here. This strain has a genome of approximately 8.9 Mb containing 7,933 predicted genes, including the ristocetin cluster and 32 additional predicted secondary metabolite biosynthesis clusters.

Antioxidant activity and free radical scavenging activities of Streptomyces sp. strain MJM 10778

OBJECTIVE To investigate the antioxidant activity of soil-borne actinobacteria. METHODS The total phenolic contents, the level of antioxidant potential by DPPH radical scavenging activity, NO scavenging activity, and ABTS radical scavenging activity in ethyl acetate extract were determined. RESULTS The 16S rDNA sequencing analysis revealed that Streptomyces sp. strain MJM 10778, which was isolated from Hambak Mountain, Korea, has 99.9% similarity to Streptomyces misionensis (S. misionensis) NBRC 13063. The physiological and the morphological test revealed that the strain MJM 10778 has different characteristics from the strain NBRC 13063. The entire antioxidant assay with the ethyl acetate extract displayed good radical scavenging activity. The IC50 values of the strain MJM 10778 extract on DPPH, NO, and ABTS radicals were identified to be 92.8 μg/mL, 0.02 μg/mL, and 134.9 μg/mL, respectively. The ethyl acetate extract of the strain MJM 10778 showed an 81.50% of cell viability at 100 μg/mL in Raw264.7 cell viability assay. CONCLUSIONS The results obtained suggest that the ethyl acetate extract of Streptomyces sp. strain MJM 10778 could be considered as a potential source of drug for the diseases that is caused by free radicals with its anti-oxidant activities and low cytotoxicity.

Cissus quadrangularis extract (CQR-300) inhibits lipid accumulation by downregulating adipogenesis and lipogenesis in 3T3-L1 cells

Highlights • CQR-300 inhibited lipid accumulation in 3T3-L1 adipocytes.• CQR-300 inhibited the differentiation of adipocytes by regulating adipogenesis.• CQR-300 reduced fatty acids and triglyceride accumulation via downregulating lipogenesis.

Glutathione S-transferase pi (GST-pi) inhibition and anti-inflammation activity of the ethyl acetate extract of Streptomyces sp. strain MJM 8637

To investigate the anti-cancer properties of soil-borne actinobacteria, MJM 8637, the glutathione S-transferase pi (GST-pi) assay, anti-tumor necrosis factor (TNF)-α assay, the level of antioxidant potential by DPPH radical scavenging activity, NO scavenging activity, and ABTS radical scavenging activity in ethyl acetate extract were determined. The 16S rDNA sequencing analysis revealed that Streptomyces sp. strain MJM 8637, which was isolated from Hambak Mountain, Korea, has 99.5% similarity to Streptomyces atratus strain NBRC 3897. The physiological and the morphological characteristics of the strain MJM 8637 were also identified. The ethyl acetate extract of MJM 8637 inhibited TNF-α production approximately 61.8% at concentration 100 μg/ml. The IC50 value of the strain MJM 8637 extract on GST-pi was identified to be 120.2 ± 1.6 μg/ml. In DPPH, NO, and ABTS radical scavenging assays, the IC50 values of the strain MJM 8637 extract were found to be 977.2 μg/ml, 1143.7 μg/ml, and 454.4 μg/ml, respectively. The ethyl acetate extract of the strain MJM 8637 showed 97.2 ± 1.3% of cell viability at 100 μg/ml in RAW 264.7 cell viability assay. The results obtained from this study suggest that the ethyl acetate extract of Streptomyces sp. strain MJM 8637 could be considered as a potential source of drug for the cancers that have multidrug resistance with its GST-pi inhibition and anti-inflammation activities, and low cytotoxicity.