• Nutrition Research and Practice
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• v.13 no.6
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• pp.473-479
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• 2019

BACKGROUND/OBJECTIVES: Anti-inflammatory and antioxidative activities of luteolin and luteolin-7-O-glucoside were compared in galactosamine (GalN)/lipopolysaccharide (LPS)-induced hepatitic ICR mice. MATERIALS/METHODS: Male ICR mice (6 weeks old) were divided into 4 groups: normal control, GalN/LPS, luteolin, and luteolin-7-O-glucoside groups. The latter two groups were administered luteolin or luteolin-7-O-glucoside (50 mg/kg BW) daily by gavage for 3 weeks after which hepatitis was induced by intraperitoneal injection of GalN and LPS (1 g/kg BW and $10{\mu}g/kg\;BW$, respectively). RESULTS: GalN/LPS produced acute hepatic injury by a sharp increase in serum AST, ALT, and $TNF-{\alpha}$ levels, increases that were ameliorated in the experimental groups. In addition, markedly increased expressions of cyclooxygenase (COX)-2 and its transcription factors, nuclear factor $(NF)-{\kappa}B$ and activator protein (AP)-1, were also significantly attenuated in the experimental groups. Compared to luteolin-7-O-glucoside, luteolin more potently ameliorated the levels of inflammatory mediators. Phase II enzymes levels and NF-E2 p45-related factor (Nrf)-2 activation that were decreased by GalN/LPS were increased by luteolin and luteolin-7-O-glucoside administration. In addition, compared to luteolin, luteolin-7-O-glucoside acted as a more potent inducer of changes in phase II enzymes. Liver histopathology results were consistent with the mediator and enzyme results. CONCLUSION: Luteolin and luteolin-7-O-glucoside protect against GalN/LPS-induced hepatotoxicity through the regulation of inflammatory mediators and phase II enzymes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1226-1234
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• 2012

3,4,3',5'-Tetrahydroxy-trans-stilbene (piceatannol) is a derivative of resveratrol with a variety of biological activities, including anti-inflammatory, anti-proliferative, and anti-cancer activities. We assessed the mechanisms by which piceatannol inhibits inflammatory responses using lipopolysaccharide (LPS)-treated Raw264.7 murine macrophages. Piceatannol (0~10 ${\mu}mol/L$) decreased LPS-induced release of nitric oxide, tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, IL-$1{\beta}$, and inhibited LPS-induced protein expression of inducible nitric oxide synthase (iNOS). Activation of nuclear factor-kappaB (NF-${\kappa}B$), activator protein (AP)-1, and signal transducer and activator of transcription 3 (STAT3) are crucial steps during an inflammatory response. Piceatannol prevented LPS-induced degradation of inhibitor of ${\kappa}B$ ($I{\kappa}B$), translocation of p65 to the nucleus, and phosphorylation of stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK). Additionally, piceatannol inhibited LPS-induced phosphorylation of STAT3 and IL-6-induced translocation of STAT3 to the nucleus. Furthermore, piceatannol increased the protein and mRNA levels of hemeoxygenase (HO)-1, the rate-limiting enzyme of heme catabolism that plays a critical role in mediating antioxidant and anti-inflammatory effects. Piceatannol further induced antioxidant response elements (ARE)-driven luciferase activity in Raw264.7 cells transfected with an ARE-luciferase reporter construct containing the enhancer 2 and minimal promoter region of HO-1. These results suggest that piceatannol exerts anti-inflammatory effects via the down-regulation of iNOS expression and up-regulation of HO-1 expression.

• Journal of Ginseng Research
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• v.44 no.3
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• pp.435-441
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• 2020

Background: As a process of aging, skeletal muscle mass and function gradually decrease. It is reported that ginsenoside Rb1 and Rb2 play a role as AMP-activated protein kinase activator, resulting in regulating glucose homeostasis, and Rb1 reduces oxidative stress in aged skeletal muscles through activating the phosphatidylinositol 3-kinase/Akt/Nrf2 pathway. We examined the effects of Rb1 and Rb2 on differentiation of the muscle stem cells and myotube formation. Methods: C2C12 myoblasts treated with Rb1 and/or Rb2 were differentiated and induced to myotube formation, followed by immunoblotting for myogenic marker proteins, such as myosin heavy chain, MyoD, and myogenin, or immunostaining for myosin heavy chain or immunoprecipitation analysis for heterodimerization of MyoD/E-proteins. Results: Rb1 and Rb2 enhanced myoblast differentiation through accelerating MyoD/E-protein heterodimerization and increased myotube hypertrophy, accompanied by activation of Akt/mammalian target of rapamycin signaling. In addition, Rb1 and Rb2 induced the MyoD-mediated transdifferentiation of the rhabdomyosarcoma cells into myoblasts. Furthermore, co-treatment with Rb1 and Rb2 had synergistically enhanced myoblast differentiation through Akt activation. Conclusion: Rb1 and Rb2 upregulate myotube growth and myogenic differentiation through activating Akt/mammalian target of rapamycin signaling and inducing myogenic conversion of fibroblasts. Thus, our first finding indicates that Rb1 and Rb2 have strong potential as a helpful remedy to prevent and treat muscle atrophy, such as age-related muscular dystrophy.

• Nutrition Research and Practice
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• v.16 no.1
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• pp.14-32
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• 2022

BACKGROUND/OBJECTIVES: Peroxisome proliferator-activated receptor-gamma co-activator-1α (PGC-1α) has a central role in regulating muscle differentiation and mitochondrial metabolism. PGC-1α stimulates muscle growth and muscle fiber remodeling, concomitantly regulating lactate and lipid metabolism and promoting oxidative metabolism. Gynostemma pentaphyllum (Thumb.) has been widely employed as a traditional herbal medicine and possesses antioxidant, anti-obesity, anti-inflammatory, hypolipemic, hypoglycemic, and anticancer properties. We investigated whether G. pentaphyllum extract (GPE) and its active compound, gypenoside L (GL), affect muscle differentiation and mitochondrial metabolism via activation of the PGC-1α pathway in murine C2C12 myoblast cells. MATERIALS/METHODS: C2C12 cells were treated with GPE and GL, and quantitative reverse transcription polymerase chain reaction and western blot were used to analyze the mRNA and protein expression levels. Myh1 was determined using immunocytochemistry. Mitochondrial reactive oxygen species generation was measured using the 2'7'-dichlorofluorescein diacetate assay. RESULTS: GPE and GL promoted the differentiation of myoblasts into myotubes and elevated mRNA and protein expression levels of Myh1 (type IIx). GPE and GL also significantly increased the mRNA expression levels of the PGC-1α gene (Ppargc1a), lactate metabolism-regulatory genes (Esrra and Mct1), adipocyte-browning gene fibronectin type III domain-containing 5 gene (Fndc5), glycogen synthase gene (Gys), and lipid metabolism gene carnitine palmitoyltransferase 1b gene (Cpt1b). Moreover, GPE and GL induced the phosphorylation of AMP-activated protein kinase, p38, sirtuin1, and deacetylated PGC-1α. We also observed that treatment with GPE and GL significantly stimulated the expression of genes associated with the anti-oxidative stress response, such as Ucp2, Ucp3, Nrf2, and Sod2. CONCLUSIONS: The results indicated that GPE and GL enhance exercise performance by promoting myotube differentiation and mitochondrial metabolism through the upregulation of PGC-1α in C2C12 skeletal muscle.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.275-284
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• 2014

This study was orchestrated with the purpose of uncovering new nutraceutical resources possessing biological activities in the plant kingdom. To fulfill our objective, we analyzed several Chinese plants and selected three possessing powerful anti-oxidative activities. The anti-oxidative and anti-inflammatory effects these three Chinese plants, Malus hupehensis, Ophiorrhiza cantonensis, and Psychotria rubra ethanol extracts were then evaluated. First of all, they possessed potent scavenging activity against 1,1-diphenyl-2-picryl hydrazyl, similar with that of ascorbic acid, used as a positive control. Moreover, they inhibited lipopolysaccharide (LPS)- and hydrogen peroxide-induced reactive oxygen species, in a dose-dependent manner, in RAW 264.7 cells. Also, they induced the expression of an anti-oxidative enzyme, heme oxygenase 1, and its upstream transcription factor, nuclear factor-E2-related factor 2. Furthermore, they suppressed LPS-induced nitric oxide (NO) formation, without cytotoxicity. The inhibition of NO formation was the result of the down regulation of inducible NO synthase (iNOS). The suppression of NO and iNOS by the three extracts might be the result of modulation by the upstream transcription factors, nuclear factor ${\kappa}B$ and activator protein-1. Taken together, these results indicate that these three Chinese plants possess potent anti-oxidative and anti-inflammatory activities. Therefore, they might be utilized as promising materials in the field of nutraceuticals.