• Food Science and Preservation
• /
• v.24 no.3
• /
• pp.325-333
• /
• 2017

This study aimed to investigate the various biological activities of Geranium thunbergii such as antimicrobial activity and protective effect against oxidative damage. To evaluate its antioxidant and antimicrobial activities, we first performed methanol extraction; this methanol extract was further partitioned using various solvents. And then, its antioxidant activity was measured using various assays including total phenolic content and protection against oxidative DNA damage, and antimicrobial activities were examined using minimum inhibiting concentration (MIC) test, and paper disc method. In addition, high-performance liquid chromatography was performed to analyze the major chemical components of ethyl acetate fraction. The G. thunbergii fraction with ethyl acetate exhibited higher antioxidant and antimicrobial activities than the other fractions. The results showed that G. thunbergii ethyl acetate fraction at $50{\mu}g/mL$ had strong DPPH and ABTS radical scavenging activities of 80.88% and 80.12%, respectively. In addition, the ethyl acetate fraction protected DNA from the oxidative damage induced by ferrous ion and hydroxyl radicals and showed high antimicrobial activity with diameter of inhibition zones ranging from 13.33 to 15.67 mm. High-performance liquid chromatography analysis revealed the major phenolic compounds of G. thunbergii to be ellagic acid and gallic acid. These results suggest that G. thunbergii might protect DNA against oxidative stress induced by reactive oxygen species and can be utilized as a natural source of antioxidant and antimicrobial agent in the food industry.

• Journal of Life Science
• /
• v.29 no.9
• /
• pp.977-985
• /
• 2019

Aster yomena (Kitam.) Honda is an edible vegetable and perennial herb belonging to the Asteraceae family, and has been used for a long time for the prevention and treatment of various diseases. Although leaf extracts of A. yomena are known to have antioxidant and anti-inflammatory effects, accurate efficacy assessments are still inadequate. In this study, we investigated whether the antioxidant efficacy of ethanol extract of A. yomena leaf (EEAY) is correlated with the anti-inflammatory effect in RAW 264.7 macrophages. The results showed that EEAY significantly inhibited the hydrogen peroxide ($H_2O_2$)-induced growth inhibition in RAW 264.7 cells, which was associated with increased expression of nuclear factor erythroid 2-related factor-2 (Nrf2) and heme oxygenase-1 (HO-1). EEAY pretreatment also effectively prevented $H_2O_2$-induced reactive oxygen species generation and apoptosis through inhibition of caspase-3 activation and poly (ADP-ribose) polymerase degradation. Additionally, EEAY significantly increased the expression and production of interleukin-10, a representative anti-inflammatory cytokine, which was associated with increased expression of toll-like receptor 4 and myeloid differentiation factor 88 at transcriptional and translational levels. Furthermore, the increased production of nitric oxide (NO) by lipopolysaccharide was markedly abolished under the condition of EEAY pretreatment, and the inhibitory effect of NO production by EEAY was further increased by hemin, an HO-1 inducer. Overall, our results suggest that EEAY is able to activate the Nrf2/HO-1 signaling pathway to protect RAW 264.7 macrophages from oxidative and inflammatory stress.

• Journal of Life Science
• /
• v.29 no.2
• /
• pp.191-197
• /
• 2019

Parkinson's disease (PD) is a progressive neurodegenerative disease that mainly affects motor system with clinical features such as bradykinesia, rigidity, tremor and abnormal posture. PD is characterized by the death of dopaminergic neurons in the substantia nigra pars compacta, which is associated with accumulation of oxidative stress and dysregulation of intracellular signaling pathway. Quercetin-3-O-glucuronide (Q3GA), a major metabolite of quercetin, has been reported to have neuroprotective effects. In this study, we examined the neuroprotective effect of Q3GA against 1-methyl-4-phenyl pyridinium ($MPP^+$)-induced neurotoxicity of PD and the underlying molecular mechanisms in SH-SY5Y cells. MTT and LDH assay showed that Q3GA significantly decreased $MPP^+$-induced cell death, which is accompanied by a reduction in poly (ADP-ribose) polymerase (PARP) cleavage. Furthermore, it attenuated $MPP^+$-induced intracellular reactive oxygen species (ROS) with the reduction of Bax/ Bcl-2 ratio. Moreover, Q3GA significantly increased the phosphorylation of Akt and cAMP response element binding protein (CREB), but it has no effects on the phosphorylation of extracellular signal-regulated kinase (ERK). Taken together, these results demonstrate that Q3GA significantly attenuates $MPP^+$-induced neurotoxicity through ROS reduction and Akt/CREB signaling pathway in SH-SY5Y cells. Our findings suggest that Q3GA might be one of the potential candidates for the prevention and/or treatment of PD.

• Biomolecules & Therapeutics
• /
• v.29 no.6
• /
• pp.685-696
• /
• 2021

In this study, we investigated the inhibitory effect of 5-aminolevulinic acid (ALA), a heme precursor, on inflammatory and oxidative stress activated by lipopolysaccharide (LPS) in RAW 264.7 macrophages by estimating nitric oxide (NO), prostaglandin E2 (PGE2), cytokines, and reactive oxygen species (ROS). We also evaluated the molecular mechanisms through analysis of the expression of their regulatory genes, and further evaluated the anti-inflammatory and antioxidant efficacy of ALA against LPS in the zebrafish model. Our results indicated that ALA treatment significantly attenuated the LPS-induced release of pro-inflammatory mediators including NO and PGE2, which was associated with decreased inducible NO synthase and cyclooxygenase-2 expression. ALA also inhibited the LPS-induced expression of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, reducing their extracellular secretion. Additionally, ALA abolished ROS generation, improved the mitochondrial mass, and enhanced the expression of heme oxygenase-1 (HO-1) and the activation of nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2) in LPS-stimulated RAW 264.7 macrophages. However, zinc protoporphyrin, a specific inhibitor of HO-1, reversed the ALA-mediated inhibition of pro-inflammatory cytokines production and activation of mitochondrial function in LPS-treated RAW 264.7 macrophages. Furthermore, ALA significantly abolished the expression of LPS-induced pro-inflammatory mediators and cytokines, and showed strong protective effects against NO and ROS production in zebrafish larvae. In conclusion, our findings suggest that ALA exerts LPS-induced anti-inflammatory and antioxidant effects by upregulating the Nrf2/HO-1 signaling pathway, and that ALA can be a potential functional agent to prevent inflammatory and oxidative damage.

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

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.48 no.3
• /
• pp.213-223
• /
• 2022

In this study, the anti-inflammatory and antioxidant effects of aerial parts of Rumex acetosa L. extract were confirmed to prevent various inflammatory diseases and skin aging caused by excessive oxidative stress. As a result of ABTS assay, it was confirmed that the radical scavenging ability increased in a concentration-dependent manner. ROS inhibitory ability was confirmed through DCF-DA assay, and concentration-dependent inhibition of ROS production was confirmed. The effect of inhibiting cell nuclear damage according to ROS was confirmed through DAPI staining. In addition, it was confirmed that the mRNA expression levels of iNOS and COX-2 were inhibited in a concentration-dependent manner through qPCR. As a result of confirming the protein levels of iNOS and COX-2 by western blotting, iNOS was significantly decreased at all concentrations, and COX-2 was significantly decreased at 800 ㎍/mL. The inhibitory effect on the production of NO generated by iNOS was confirmed by NO assay, and NO was decreased in a concentration-dependent manner. In addition, phosphorylation of ERK and JNK in the MAPKs signaling pathway were inhibited. Therefore, Rumex acetosa L. has the potential to be used as an anti-inflammatory and antioxidant cosmetic raw material by showing anti-inflammatory and antioxidant effects through the MAPKs pathway.

• The Korea Journal of Herbology
• /
• v.33 no.6
• /
• pp.19-28
• /
• 2018

Objectives : The objective of this study was to investigate the protective effect of Flaxseed oil and Chrysanthemi Indici Flos 50% ethanol extract in an HCl/ethanol induced acute gastritis model. Methods : ICR mice were divided into 6 groups; normal mice (Nor), gastritic mice with distilled water (Veh), gastritic mice with 10 mg/kg sucralfate (SC), gastritic mice with 16 g/㎏ Flaxseed oil (FO), gastritic mice with FO + 50 mg/kg Chrysanthemi Indici Flos (FCL), and gastritic mice with FO + 100 mg/kg Chrysanthemi Indici Flos (FCH). Then, mice were orally administered with 150 mM HCl/60% ethanol and caused acute gastritis. After 1 hr, mice were sacrificed, and blood and stomach tissue were collected. Results : Administration of FCL and FCH to mice prior to the induction of gastritis was found to reduce gastric injury. reactive oxygen species (ROS) and peroxy nitrite ($ONOO^-$) levels of stomach tissues were significantly decreased in FO, FCL, and FCH compared to Veh group. As results of stomach protein analyses, FCL and FCH effectively reduce inflammatory-related factors such as inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), and interleukin 1 beta ($IL-1{\beta}$) in gastric lesion mice. In addition, nuclear factor kappa B p65 ($NF-{\kappa}B$ p65) and phosphorylation inhibitor of nuclear factor kappa $B{\alpha}(p-I{\kappa}B{\alpha})$ were down-regulated in FCL and FCH administrated gastric lesion mice. Conclusions : These results suggest that FCL and FCH has an inhibitory effect against gastric injury. Therefore, FCL and FCH has the potential to be used as a natural therapeutic drug.

• Journal of Life Science
• /
• v.32 no.9
• /
• pp.712-720
• /
• 2022

The purpose of this study was to investigate the efficacy of rat corneal-derived epithelial cells as an in vitro model to evaluate the harmfulness of the cornea caused by particulate matter 2.5 (PM_2.5). To establish an experimental model for the effect of PM_2.5 on corneal epithelial cells, it was confirmed that primary cultured cells isolated from rat eyes were corneal epithelial cells through pan-cytokeratin staining. Our results showed that PM_2.5 treatment reduced cell viability of primary rat corneal epithelial (RCE) cells, which was associated with the induction of apoptosis. PM_2.5 treatment also increased the generation of reactive oxygen species due to mitochondrial dysfunction. In addition, the production of nitric oxide and inflammatory cytokines was increased in PM_2.5-treated RCE cells. Furthermore, through heatmap analysis showing various expression profiling between PM_2.5-exposed and unexposed RCE cells, we proposed five genes, including BLNK, IL-1RA, Itga2b, ABCb1a and Ptgs2, as potential targets for clinical treatment of PM-related ocular diseases. These findings indicate that the primary RCE cell line is a useful in vitro model system for the study of PM_2.5-mediated pathological mechanisms and that PM2.5-induced oxidative and inflammatory responses are key factors in PM2.5-induced ocular surface disorders.

• Journal of Nutrition and Health
• /
• v.55 no.5
• /
• pp.523-532
• /
• 2022

Vitamin C is an important physiological antioxidant which neutralizes reactive oxygen species (ROS) and reduces the oxidative stress in the body. Although it has been associated with various diseases, few studies have reported the dose-response relationship between vitamin C intake, storage and functions in the body, including its antioxidant function. The criteria to establish the Dietary Reference Intakes for Koreans (KDRIs) for vitamin C were based on the changes in plasma concentrations and saturation of leukocytes according to intake levels and the effects on antioxidant capacity and risk of metabolic diseases. When establishing the 2020 vitamin C KDRI, while there was no change in the criteria from those of 2015, the reference values were recalculated and revised to reflect changes such as the new standard weight by age. As the number of people consuming dietary supplements has increased over the last decade, only about 10% of adults consume less than the average total vitamin C, but the proportion of adolescents and elderly who consume less than the average is high. On the other hand, as the intake of vitamin C supplements increases, the proportion of people consuming excessive vitamin C is also increasing. There is a body of opinion that it is necessary to establish a vitamin C KDRI for smokers or people with chronic diseases such as the metabolic syndrome, but these standards have not been established due to the lack of supporting scientific evidence. As a result, studies to establish vitamin C KDRI for Korean smokers and patients with the metabolic syndrome, as well as studies on the excessive intake of vitamin C due to supplementation and interactions with other nutrients, are needed.

• Journal of Nutrition and Health
• /
• v.56 no.2
• /
• pp.140-154
• /
• 2023

Purpose: Deodeok (Codonopsis lanceolata) is generally used in conventional medicines and is considered to have remedial properties to cure several diseases. However, application of the C. lanceolata bud as a novel food ingredient has not been fully explored. Hydrogen peroxide (H₂O₂) is associated with the production of oxidative damage that results in mutagenesis, carcinogenesis, and cell death. This study examines the neuroprotective effect of C. lanceolate bud extracts (CLBE) on H₂O₂-stimulated apoptosis in SH-SY5Y cells. Methods: C. lanceolata bud of length 10 to 15 cm was collected and extracted using 70% ethanol. Cytotoxicity was evaluated by the EZ-cytox reagent, measurement of lactic dehydrogenase (LDH) release and reactive oxygen species (ROS). The morphological changes of the nuclei were determined using the Hoechst 33258 dye. Enzyme activities were analyzed using the caspase activity assay kit. Related protein expressions were quantified by the Western blot immunoassay in H₂O₂-stimulated SH-SY5Y cells. Results: Cell viability, LDH release and ROS generation, demonstrated neuroprotective effects of CLBE in H₂O₂-stimulated SH-SY5Y cells. The occurrence of apoptosis in H₂O₂-stimulated cells was confirmed by caspase activity, which was increased in H₂O₂-stimulated SH-SY5Y cells compared to the unexposed group. Pretreatment of CLBE was observed to inhibit the H₂O₂-stimulated apoptosis. In addition, exposure to CLBE resulted in increased expression of the Bcl-2 (B cell lymphoma 2) protein and decreased expression of the Bax (Bcl2 associated X) protein. Conclusion: This study shows that exposure to CLBE alleviates the H₂O₂-stimulated neuronal damage in SH-SY5Y cells. Our results indicate the potential application of CLBE in neurodegenerative disease therapy or prevention.