• Food Science of Animal Resources
• /
• v.33 no.3
• /
• pp.411-416
• /
• 2013

This study aimed to examine the mechanisms underlying the effects of Garcinia cambogia extract on the adipogenic differentiation of 3T3-L1 cells and long-chain saturated fatty acid-induced lipotoxicity of HepG2 cells. 3T3-L1 preadipocytes, mouse embryonic fibroblast-adipose like cell line, were treated with MDI solution (0.5 mM IBMX, 1 ${\mu}M$ dexamethasone, 10 ${\mu}g/mL$ insulin) to generate a cellular model of adipocyte differentiation. Using this cellular model, the anti-obesity effect of Garcinia cambogia extract was evaluated. MDI-induced lipid accumulation and expression of adipogenesis-related genes were detected by Oil red O staining, Nile Red staining, and Western blot analysis. Effects Garcinia cambogia extract on palmitate-induced lipotoxicity was also analyzed by MTT assay, LDH release, and DAPI staining in HepG2 cells. Garcinia cambogia extract significantly suppressed the adipogenic differentiation of preadipocytes and intracellular lipid accumulation in the differentiating adipocytes. Garcinia cambogia extract also markedly inhibited the expression of peroxisome proliferator- activated receptor ${\gamma}2$ ($PPAR{\gamma}2$), CCAT/enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$), and adipocyte protein aP2 (aP2). In addition, Garcinia cambogia extract significantly attenuated palmitate-induced lipotoxicity in HepG2 cells. Palmitateinduced cellular damage and reactive aldehydes were also significantly reduced in the presence of Garcinia cambogia extract. These findings suggest that the Garcinia cambogia extract inhibits the adipogenic differentiation of 3T3-L1 preadipocytes, probably by regulating the expression of multiple genes associated with adipogenesis such as $PPAR{\gamma}2$, $C/EBP{\alpha}$, aP2, and thereby modulating fatty acid-induced lipotoxicity to reduce cellular injury in hepatocytes.

• Journal of Food Hygiene and Safety
• /
• v.35 no.1
• /
• pp.93-101
• /
• 2020

Seakso 1, a maize hybrid, was developed in 2008 by Gangwon Agricultural Research and Extension Services in Korea and registered in 2011. It is single-cross hybrid, semi-flint, deep-purple variety of corn, variety of are yellow, while the husks and cobs are purple. Due to the sensitivity of Seakso 1 to excess moisture after seeding, water supply should be carefully managed, and it should be harvested at a suitable time to obtain the highest anthocyanin content. This study investigated the hepatoprotective effect of Saekso 1 corn husk and cob extracts (EHCS) in oleic acid-induced non-alcoholic fatty liver disease (NAFLD) in HepG2 cells. EHCS showed a high level of lipid accumulation inhibiting effect. EHCS also suppressed triglyceride accumulation and inhibited expression of lipid marker genes, such as sterol regulatory element binding protein-1c (SREBP-1c) and sterol regulatory element binding protein-1a (SREBP-1a). Analysis by western blot of the expression of p-AMPK, p-SREBP1, PPARα, and FAS proteins showed that the incidence of SREBP1 protein, a major factor involved in lipid metabolism in the liver, has decreased significantly after treatment with the extracts. Moreover, the protein-induced expression of FAS, a major enzyme involved in the biosynthetic pathways of fatty acids, was decreased significantly in all concentrations. These results suggest that EHCS is a potent agent for the treatment of NAFLD.

• Journal of Life Science
• /
• v.24 no.3
• /
• pp.274-283
• /
• 2014

Oxidative stress causes tissue damage and facilitates the progression of metabolic diseases, including diabetes, cardiovascular heart diseases, and obesity. Lipid accumulation and obesity-related complications have been observed in the presence of extensive oxidative stress. As part of an ongoing study to develop therapeutic supplements, Sargassum sp. were tested for their ability to scavenge free radicals and intracellular reactive oxygen species (ROS), as well as to suppress lipid accumulation. Three species, S. hemiphyllum, S. thunbergii, and Sargassum horneri, were shown to scavenge free radicals in a di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) assay. In addition, Sargassum sp. was shown to scavenge intracellular ROS and to decrease nitric oxide (NO) production in $H_2O_2$ and lipopolysaccharide (LPS)-induced in RAW264.7 mouse macrophages, respectively. Taken together, the results suggest that Sargassum sp. possess huge potential to relieve oxidative stress and related complications, as well as lipid-induced oxidation. They indicate that S. hemiphyllum, S. thunbergii, and S. horneri are potent functional supplements that can produce beneficial health effects through antioxidant and antiobesity activities, with S. hemiphyllum being the most potent among the Sargassum sp. tested. A potential mechanism for the effect of Sargassum sp. on the suppression of lipid accumulation in differentiating 3T3-L1 mouse preadipocytes through deactivation of the peroxisome proliferator-activated receptor ${\gamma}$ (PPAR ${\gamma}$) is presented.

• Journal of Life Science
• /
• v.22 no.12
• /
• pp.1688-1696
• /
• 2012

Oenanthe javanica has been used as a food source and also in traditional folk medicine for its detoxifying properties and anti-microbial effects since ancient times. In this study, we evaluated the effect and mechanism of O. javanica seed methanol extract (OJSE) on adipocyte differentiation by 3T3-L1 preadipocytes. Under non-toxic conditions, OJSE treatment resulted in a dose-dependent inhibition of lipid droplet generation and triglyceride accumulation by suppressing adipocyte differentiation, which are associated with the decreased expression of key proadipogenic transcription factors including CCAAR/enhancer binding protein ${\alpha}$, ${\beta}$ ($C/EBP{\alpha}$, $C/EBP{\beta}$) and peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$). OJSE also significantly inhibited proliferation and differentiation of 3T3-L1 preadipocytes through G1-phase arrest, indicating that OJSE blocked mitotic clonal expansion during adipocyte differentiation. Investigation of the alteration of G1 phase arrest-related proteins indicated a dose-dependent increase in the expression of p21 and reduction in expression of cyclin E, Cdk2, E2F-1 and phospho-Rb by OSJE. Taken together, these results suggest that OJSE inhibits adipocyte differentiation by blocking the mitotic clonal expansion, which is accompanied by preadipocyte cell cycle arrest.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.5
• /
• pp.651-663
• /
• 2016

Corn silk, Job's tears, Lentinus edodes, and apple peel 70% ethanol extracts (CS, JT, LE, and AP) were studied for their antioxidant activities. CS among all extracts showed the highest antioxidant activities based on total polyphenol and flavonoid contents, 2,2-diphenyl-${\beta}$-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radical scavenging activity, and reducing power. Adipocyte differentiation was investigated by Oil Red O staining assay using CS, JT, LE, AP, and extract of developed bread containing corn silk, Job's tears, Lentinus edodes, and apple peel (DB) treated to 3T3-L1 adipocytes. DB1 and DB2 showed anti-adipogenic and antioxidant effects. Triglyceride (TG) accumulation in 3T3-L1 cells was measured, and among the samples tested (CS, JT, LE, and AP), CS was found to have the highest inhibitory activity against TG accumulation of differentiated 3T3-L1 adipocytes and regulated factors associated with adipogenesis. CS suppressed lipid droplet formation and adipocyte differentiation in 3T3-L1 cells in a dose-dependent manner. We examined the effects of CS on the levels of CCAAT-enhancer-binding protein ${\beta}(C/EBP{\beta})$, peroxisome proliferator activated receptor ${\gamma}(PPAR{\gamma})$, and adipocyte-specific lipid binding protein (aP2) mRNA as well as protein levels in 3T3-L1 cells treated with CS at various concentrations (0, 10, 50, and $100{\mu}g/mL$) during adipocyte differentiation and treatment with CS in 3T3-L1 adipocytes down-regulated expression of $PPAR{\gamma}$ and aP2 mRNA. CS also significantly inhibited up-regulation of $C/EBP{\beta}$, $PPAR{\gamma}$, and aP2 proteins during adipocyte differentiation. These data indicate that DBs have anti-adipogenic activity induced by CS in 3T3-L1 preadipocytes, and CS exerts anti-adipogenic activity by inhibiting expression of $C/EBP{\beta}$, $PPAR{\gamma}$, and aP2 signaling pathway in 3T3-L1 adipocytes. JT, LE, and AP had no inhibitory effects on differentiation of 3T3-L1 preadipocytes but displayed strong antioxidant effects. These results suggest that the developed bread may be a health beneficial food that can prevent or treat obesity and diseases induced by oxidative stress.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.6
• /
• pp.813-819
• /
• 2010

The intracellular lipid droplets were stained with Oil Red O dye and quantified. Compared to the control, lipid accumulation was significantly decreased by 19.4% with the treatment of LCM at the concentration of $1000\;{\mu}g$/mL. Intracellular triglyceride (TG) level was also reduced by 21% at the concentration of $1000\;{\mu}g$/mL. To determine the mechanism for the reduction in TG content, levels of glucose uptake and glycerol release were measured. Incubation of the 3T3-L1 adipocytes with LCM did not affect the cellular uptake of glucose. However, the level of free glycerol released into the cultured medium drastically increased by 24.3% with the treatment of LCM. In subsequent measurements using quantitative real-time PCR, mRNA levels of hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) except lipoprotein lipase (LPL) were significantly elevated at higher concentration. These results suggest that LCM partially stimulates the lipolysis through the induction of HSL and/or ATGL gene expression, resulting in the reduced lipid accumulation and increased glycerol release.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.11
• /
• pp.1688-1694
• /
• 2014

Jeju Hallabong Tangor (Citrus kiyomi${\times}$ponkan) is a Citrus species with a variety of physiological properties such as anti-oxidant, anti-inflammation, anti-cancer, and anti-obesity. We investigated the anti-obesity effects of Hallabong Tangor peel extracts before (HLB) and after (HLB-C) bioconversion with cytolase based on modulation of adipocyte differentiation and lipid metabolism in 3T3-L1 adipocytes. Treatment with cytolase decreased flavanone rutinoside forms (narirutin and hesperidin) and increased flavanone aglycone forms (naringenin and hesperetin). During adipocyte differentiation, 3T3-L1 cells were treated with 0.5 mg/mL of Sinetrol (a positive control), HLB or HLB-C. Adipocyte differentiation was inhibited in both citrus groups, but not in control and Sinetriol groups. HLB and HLB-C tended to reduce insulin-induced mRNA levels of CCAAT/enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$) and sterol regulatory element-binding protein 1c (SREBP1c). Compared to the control and Sinetrol groups, HLB and HLB-C markedly suppressed insulin-induced protein expression of $C/EBP{\alpha}$ and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$). The HLB and Sinetrol groups, but not HLB-C group, significantly increased adipolytic activity with higher release of free glycerol compared to the control group in differentiated 3T3-L1 adipocytes. These results suggest that bio-conversion of Hallabong Tangor peel extracts with cytolase increases aglycone flavonoids. Irrespective of bioconversion, both Hallabong Tangor peel extracts exert anti-obesity effects that may contribute to prevention of obesity through inhibition of adipocyte differentiation or induction of adipolytic activity.

• Journal of Life Science
• /
• v.24 no.5
• /
• pp.505-514
• /
• 2014

To examine the anti-obese activity of miscellaneous cereal grains, 80% ethanol extracts from eight selected miscellaneous cereal grains were compared for their cytotoxic effects on 3T3-L1 murine preadipocytes. The ethanol extract of proso millet exhibited the highest cytotoxicity. Further fractionation of the ethanol extract with methylene chloride, ethyl acetate, and n-butanol showed that the cytotoxicity of the ethanol extract was mainly partitioned into the butanol fraction. As compared with differentiated mature adipocytes, 3T3-L1 preadipocytes were more susceptible to the cyctotoxicity of the butanol fraction. When each organic solvent fraction (25 ${\mu}g/ml$) was added during the differentiation period for 6 days, the cell viability was not affected significantly except for the butanol fraction, but the intracellular lipid accumulation declined to a level of 81.5%~50.3% of the control. The Oil Red O staining data also demonstrated that the ethanol extract as well as the butanol fraction could inhibit the differentiation of 3T3-L1 preadipocytes into mature adipocytes. The presence of the butanol extract during the induced adipocytic differentiation also resulted in a significant reduction in the expression levels of critical adipogenesis mediators $(C/EBP{\alpha}$, $PPAR{\gamma}$, aP2, and LPL) to a barely detectable or undetectable level and the cells retained the fibroblast-like morphology of 3T3-L1. In 3T3-L1 cells, the cytotoxicity of the butanol fraction (50-100 ${\mu}g/ml$) was accompanied by mitochondrial membrane potential (${\Delta}{\psi}m$) loss, caspase-3 activation, and PARP degradation. Taken together, these results indicate that proso millet grains possess pro-apoptotic and anti-adipocytic activities toward adipocytes, which can be applicable to prevention of obesity.

• Journal of Life Science
• /
• v.21 no.5
• /
• pp.720-728
• /
• 2011

Garlic (Allium sativum) has been used as a source food as well as a traditional folk medicine ingredient since ancient times. Aged black garlic is a type of fermented garlic and is expected to have stronger anticancer and antioxidant activities than raw garlic. However, the mechanisms of their inhibitory effects on adipocyte differentiation and adipogenesis are poorly understood. In the present study, the effects and mechanisms of water extracts of raw garlic (WERG) and aged black garlic (WEABG) on adipocyte differentiation and adipogenesis in 3T3-L1 preadipocytes were investigated. Treatment with WEABG significantly suppressed terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner as confirmed by a decrease in lipid droplet number and lipid content through Oil Red O staining, however WERG had no such effect. In addition, WEABG reduced accumulation of cellular triglyceride, which is associated with a significant inhibition of key pro-adipogenic transcription factors including peroxisome proliferator-activated receptor ${\gamma}$ (PPAR${\gamma}$), cytidine-cytidine-adenosine-adenosine-thymidine (CCAAT)/enhancer binding proteins ${\alpha}$ (C/EBP${\alpha}$) and C/EBP${\beta}$. Taken together, these results provide important new insight that aged black garlic might inhibit adipogenesis by suppressing the pro-adipogenic transcription factors in 3T3-L1 preadipocytes, and further studies will be needed to identify the active compounds that confer the anti-obesity activity of aged black garlic.

• Journal of Animal Science and Technology
• /
• v.52 no.4
• /
• pp.265-270
• /
• 2010

Adipogenesis has been one of the most intensely studied models of cellular differentiation. During adipogenesis, differential expression of many adipogenesis related genes lead to profound changes in cellular, morphological, and physiological characteristics of the differentiating cells. The aim of the present study was to examine the expression levels of adipogenic candidate genes, cAMP early repressor (ICER), nephroblastoma over-expressed protein (NOV), heat shock protein beta 1 (HSPB1) and succinate dehydrogenase (SDH), during adipogenesis of bovine mesenchymal stem cells (BMSC). The BMSC were cultured in DMEM / low glucose medium with adipogenic inducers for 6 days and the expression of various candidate genes which seemed related to adipogenesis were measured by real-time PCR. This study showed that the expression of peroxisome proliferator activated receptor ${\gamma}$(PPAR${\gamma}$) and fatty acid binding protein 4 (FABP4) genes as adipogenic indicators were increased to 3.11 and 3.11 folds on day 6 than on day 0, respectively (p<0.05). To determine whether candidate genes were related to adipogenesis, the expression levels of ICER, NOV, HSPB1, and SDH genes were measured during adipogenesis in BMSC. Our results showed that the expression level of ICER gene was significantly increased to 4.12 folds (0.01729 vs. 0.07138; p<0.05), whereas NOV, HSPB1, and SDH genes were decreased to 2.89, 3.18 and 2.36 folds, respectively, on day 6 when compared to day 0. These results suggest that these candidate genes have stimulatory or inhibitory effects on adipogenesis in BMSC, indicating that these genes may be directly or indirectly related to the adipogenic event of adipose precursor cells.