• Journal of Ginseng Research
• /
• v.46 no.6
• /
• pp.759-770
• /
• 2022

Background: Aerobic cellular respiration provides chemical energy, adenosine triphosphate (ATP), to maintain multiple cellular functions. Sirtuin 1 (SIRT1) can deacetylate peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) to promote mitochondrial biosynthesis. Targeting energy metabolism is a potential strategy for the prevention and treatment of various diseases, such as cardiac and neurological disorders. Ginsenosides, one of the major bioactive constituents of Panax ginseng, have been extensively used due to their diverse beneficial effects on healthy subjects and patients with different diseases. However, the underlying molecular mechanisms of total ginsenosides (GS) on energy metabolism remain unclear. Methods: In this study, oxygen consumption rate, ATP production, mitochondrial biosynthesis, glucose metabolism, and SIRT1-PGC-1α pathways in untreated and GS-treated different cells, fly, and mouse models were investigated. Results: GS pretreatment enhanced mitochondrial respiration capacity and ATP production in aerobic respiration-dominated cardiomyocytes and neurons, and promoted tricarboxylic acid metabolism in cardiomyocytes. Moreover, GS clearly enhanced NAD⁺-dependent SIRT1 activation to increase mitochondrial biosynthesis in cardiomyocytes and neurons, which was completely abrogated by nicotinamide. Importantly, ginsenoside monomers, such as Rg1, Re, Rf, Rb1, Rc, Rh1, Rb2, and Rb3, were found to activate SIRT1 and promote energy metabolism. Conclusion: This study may provide new insights into the extensive application of ginseng for cardiac and neurological protection in healthy subjects and patients.

• Journal of Life Science
• /
• v.20 no.5
• /
• pp.729-735
• /
• 2010

In our previous study, it was reported that an herbal mixture, SH21B, inhibits fat accumulation and adipogenesis both in vitro and in vivo models of obesity. SH21B is a mixture composed of seven herbs: Scutellaria baicalensis Georgi, Prunus armeniaca Maxim, Ephedra sinica Stapf, Acorus gramineus Soland, Typha orientalis Presl, Polygala tenuifolia Willd, and Nelumbo nucifera Gaertner (Ratio 3:3:3:3:3:2:2). The aim of this study was to investigate the detailed molecular mechanisms of the effects of SH21B on various regulators of the adipogenesis pathway. During the adipogenesis of 3T3-L1 cells, SH21B significantly decreased the expression levels of central transcription factors of adipogenesis, such as peroxisome proliferator-activated receptor (PPAR)$\gamma$ and CCAAT/enhancer binding protein (C/EBP)$\alpha$. To elucidate the detailed molecular mechanism of the anti-adipogenic effects of SH21B, we examined the expression levels of the various pro-adipogenic or anti-adipogenic regulators of adipogenesis upstream of $PPAR{\gamma}$ and C/$EBP{\alpha}$. The mRNA levels of Krox20 and Kruppel-like factor (KLF) 15, which are pro-adipogenic regulators, were significantly down-regulated by SH21B treatment, whereas the mRNA levels of C/$EBP{\gamma}$ and KLF5 were not changed. KLF2 and C/EBP homologous protein (CHOP), which are anti-adipogenic regulators, were significantly up-regulated by SH21B treatment. These results suggest that the molecular mechanism of the anti-adipogenic effect of SH21B involves both the down-regulations of pro-adipogenic regulators, such as Krox20 and KLF15, and the up-regulations of anti-adipogenic regulators, such as KLF2 and CHOP, which results in the suppression of central transcription factors of adipogenesis including $PPAR{\gamma}$ and C/$EBP{\alpha}$.

• Journal of Life Science
• /
• v.27 no.2
• /
• pp.155-163
• /
• 2017

Mori Folium, the leaf of Morus alba, is a traditional medicinal herb that shows various pharmacological activities such as antiinflammatory, antidiabetic, antimelanogenesis, antioxidant, antibacterial, antiallergic, and immunomodulatory activities. However, the mechanisms of their inhibitory effects on adipocyte differentiation and adipogenesis remain poorly understood. In the present study, we investigated the inhibition of adipocyte differentiation and adipogenesis by ethanol extracts of Mori Folium (EEMF) in 3T3-L1 preadipocytes. Treatment with EEMF suppressed the terminal differentiation of 3T3-L1 preadipocytes in a dose-dependent manner, as confirmed by a decrease in the lipid droplet number and lipid content through Oil Red O staining. EEMF significantly reduced the accumulation of cellular triglyceride, which is associated with a significant inhibition of pro-adipogenic transcription factors, including sterol regulatory element-binding protein-1c (SREBP-1c), peroxisome proliferator-activated receptor-${\gamma}$ ($PPAR{\gamma}$), and CCAAT/enhancer-binding proteins ${\alpha}$ ($C/EBP{\alpha}$) and ${\beta}$ ($C/EBP{\beta}$). In addition, EEMF potentially downregulated the expression of adipocyte-specific genes, including adipocyte fatty acid binding protein (aP2) and leptin. Furthermore, EEMF treatment effectively increased the phosphorylation of the AMP-activated protein kinase (AMPK) and acetyl CoA carboxylase (ACC); however, treatment with a potent inhibitor of AMPK, compound C, significantly restored the EEMF-induced inhibition of pro-adipogenic transcription factors and adipocyte-specific genes. These results together indicate that EEMF has preeminent effects on the inhibition of adipogenesis through the AMPK signaling pathway, and further studies will be needed to identify the active compounds in Mori Folium.

• Journal of Life Science
• /
• v.19 no.12
• /
• pp.1802-1807
• /
• 2009

Platycodin D, a major component of Platycodi radix, is known to have various activities including anti-inflammatory, anti-hyperlipidemic, anti-tumor activities and others. Recently, it was reported that platycodin D inhibits fat accumulation and adipogenesis. The aim of this study was to investigate whether various adipogenic regulators are modulated by platycodin D treatment during the adipogenesis of 3T3-L1 cells. mRNA levels of terminal markers of adipogenesis such as ADIPOQ (adiponectin) and GLUT (glucose transporter) 4, which were quantified by real time PCR, were decreased by platycodin D treatment. mRNA expression of PPAR (peroxisome proliferator-activated receptor) $\gamma$ and C/EBP (CCAAT/enhaner binding protein) $\alpha$, which are central transcription factors of adipogenesis, were also decreased by platycodin D treatment. To elucidate the detailed molecular mechanism of platycodin D-induced inhibition of adipogenesis, we analyzed mRNA expression of upstream regulators of PPAR$\gamma$ and C/EPB$\alpha$. mRNA levels of the pro-adipogenic regulators, KROX20 and KLF (Kruppel-like factor) 15 were markedly down-regulated by platycodin D treatment. On the other hand, mRNA expression of CHOP (C/EBP homologous protein), an anti-adipogenic regulator, was significantly up-regulated by platycodin D treatment. mRNA levels of other pro-adipogenic regulators, C/EBP$\beta$ and C/EPB$\delta$, were not affected by platycodin D treatment, and another anti-adipogenic regulator, C/EBP$\gamma$ was also not affected by platycodin D treatment. Taken together, these results suggest that platycodin D-induced inhibition of adipogenesis is mediated by gene interactions including the down-regulation of pro-adipogenic regulators, KROX20 and KLF15, and the up-regulation of an anti-adipogenic regulator, CHOP.

• 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.

• Korean Journal of Poultry Science
• /
• v.42 no.3
• /
• pp.231-238
• /
• 2015

The present study aimed to investigate the effects of lycopene on hepatic metabolic- and immune-related gene expression in laying hens. A total of 48 25-week-old White Leghorn hens were randomly allocated into four groups consisting of four replicates of three birds: control (basal diet), T1 (basal diet + 10 mg/kg of tomato powder-containing lycopene), T2 (basal diet + 10 mg/kg of micelles of tomato powder-containing lycopene), and T3 (basal diet + 10 mg/kg of purified lycopene). Chickens were fed ad libitum for 5 weeks, and then total RNA was extracted from the livers for quantitative RT-PCR analysis. Peroxisome proliferator-activated receptor ${\gamma}$ (PPAR${\gamma}$) expression was decreased in the liver of chickens after lycopene supplementation (P<0.05). Micellar lycopene supplementation decreased the expression of PPAR${\gamma}$ target genes including fatty acid binding protein 4 (FABP4) and fatty acids synthase (FASN) in the T2 group (P<0.05). Sterol regulatory element-binding protein 2 (SREBP2) and C/EBP-${\alpha}$ were also downregulated in hens fed with micellar lycopene (P<0.05). Glucose transporter 8 (GLUT-8) was upregulated in the T2 and T3 groups (P<0.05). However, the expression of carnitine palmitoyltransferase 1 (CPT-1) was not changed by lycopene supplementation. Pro-inflammatory cytokines such as tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$) and interleukin 6 (IL-6) were downregulated by lycopene supplementation (P<0.05). These data suggest that the type of lycopene supplementation is critical and that micelles of tomato powder-containing lycopene may play an important role in the modulation of lipid metabolism and immunity in chickens.

• Food Science and Preservation
• /
• v.18 no.3
• /
• pp.366-373
• /
• 2011

Recent studies suggested that Cheonnyuncho is a significant source of bioactive phenolic compounds, comparable to phytochemicals, including green tea and onion. In this study, the hot-water and 80% ethanolic extracts of Cheonnyuncho were assessed as to their total phenol content, total flavonoids content, antioxidant activity (DPPH radical-scavenging activity and reducing power), and anti-obesity activity. The results showed that the total phenol contents of the hot water extract and the 80% ethanolic extract were $16.52{\pm}3.87$ and $13.44{\pm}0.85$ mg GAE/g, respectively. The total flavonoids content was detected only in the 80% ethanolic extract, however, with a 778.08 ${\mu}g$ catechin equivalents/g content. The DPPH radical-scavenging activity and reducing power of the 80% ethanolic extract from Cheonnyuncho was significantly higher than those of the water extract (p < 0.05). During the adipocyte differentiation, the 80% ethanolic extract of Cheonnyuncho more significantly inhibited lipid accumulation and ROS production than the 3T3-L1 cells that were treated with hot water extract. Furthermore, the 80% ethanolic extract of Cheonnyuncho suppressed the mRNA abundance of the adipogenic transcription factor, $PPAR{\gamma}$ (peroxisome proliferator-activated receptor ${\gamma}$), and its target gene, aP2 (adipocyte protein 2). These results indicate that Cheonnyuncho extracts can inhibit adipogenesis through a mechanism that involves direct down regulation of $PPAR{\gamma}$ gene expression or via modulation of ROS production associated with radical-scavenging activities.

• Journal of Ginseng Research
• /
• v.41 no.3
• /
• pp.257-267
• /
• 2017

Background: Heat-processed ginseng, sun ginseng (SG), has been reported to have improved therapeutic properties compared with raw forms, such as increased antidiabetic, anti-inflammatory, and antihyperglycemic effects. The aim of this study was to investigate the antiobesity effects of SG through the suppression of cell differentiation and proliferation of mouse 3T3-L1 preadipocyte cells and the lipid accumulation in Caenorhabditis elegans. Methods: To investigate the effect of SG on adipocyte differentiation, levels of stained intracellular lipid droplets were quantified by measuring the oil red O signal in the lipid extracts of cells on differentiation Day 7. To study the effect of SG on fat accumulation in C. elegans, L4 stage worms were cultured on an Escherichia coli OP50 diet supplemented with $10{\mu}g/mL$ of SG, followed by Nile red staining. To determine the effect of SG on gene expression of lipid and glucose metabolism-regulation molecules, messenger RNA (mRNA) levels of genes were analyzed by real-time reverse transcription-polymerase chain reaction analysis. In addition, the phosphorylation of Akt was examined by Western blotting. Results: SG suppressed the differentiation of 3T3-L1 cells stimulated by a mixture of 3-isobutyl-1-methylxanthine, dexamethasone, and insulin (MDI), and inhibited the proliferation of adipocytes during differentiation. Treatment of C. elegans with SG showed reductions in lipid accumulation by Nile red staining, thus directly demonstrating an antiobesity effect for SG. Furthermore, SG treatment down-regulated mRNA and protein expression levels of peroxisome proliferator-activated receptor subtype ${\gamma}$ ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein-alpha ($C/EBP{\alpha}$) and decreased the mRNA level of sterol regulatory element-binding protein 1c in MDI-treated adipocytes in a dose-dependent manner. In differentiated 3T3-L1 cells, mRNA expression levels of lipid metabolism-regulating factors, such as amplifying mouse fatty acid-binding protein 2, leptin, lipoprotein lipase, fatty acid transporter protein 1, fatty acid synthase, and 3-hydroxy-3-methylglutaryl coenzyme A reductase, were increased, whereas that of the lipolytic enzyme carnitine palmitoyltransferase-1 was decreased. Our data demonstrate that SG inversely regulated the expression of these genes in differentiated adipocytes. SG induced increases in the mRNA expression of glycolytic enzymes such as glucokinase and pyruvate kinase, and a decrease in the mRNA level of the glycogenic enzyme phosphoenol pyruvate carboxylase. In addition, mRNA levels of the glucose transporters GLUT1, GLUT4, and insulin receptor substrate-1 were elevated by MDI stimulation, whereas SG dose-dependently inhibited the expression of these genes in differentiated adipocytes. SG also inhibited the phosphorylation of Akt (Ser473) at an early phase of MDI stimulation. Intracellular nitric oxide (NO) production and endothelial nitric oxide synthase mRNA levels were markedly decreased by MDI stimulation and recovered by SG treatment of adipocytes. Conclusion: Our results suggest that SG effectively inhibits adipocyte proliferation and differentiation through the downregulation of $PPAR{\gamma}$ and $C/EBP{\alpha}$, by suppressing Akt (Ser473) phosphorylation and enhancing NO production. These results provide strong evidence to support the development of SG for antiobesity treatment.

• 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.23 no.1
• /
• pp.69-78
• /
• 2013

Vitis amurensis Rupreche, a sort of grape, grows naturally in Asian countries. It is known for important biological effects such as antioxidation, anti-inflammation, neuroprotection, and angiogenesis inhibition. Although its root is used as a traditional folk medicine in Korea, the root's biological activities are poorly studied. In the present study, the effects of V. amurensis root methanol extract (VARM) and its solvent fractions on adipocyte differentiation and adipogenesis in 3T3-L1 preadipocytes were investigated. The VARM significantly suppressed adipocyte differentiation, lipid accumulation, and the triglyceride (TG) content of 3T3-L1 preadipocytes in a dose-dependent manner, without cytotoxicity. To identify active molecules, the VARM was fractionated with a series of organic solvents including dichloromethane ($CH_2Cl_2$), ethyl acetate (EtOAc), and n-butanol (n-BuOH). All the fractions also showed inhibition of lipid accumulation in the 3T3-L1 preadipocytes. The $CH_2Cl_2$ fraction showed the most powerful anti-obesity effect through the modulation of cytidine-cytidine-adenosine-adenosinethymidine (CCAAT)/enhancer binding protein ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$, peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) gene and protein expression. Oleanolic acid was one of the main active compounds involved in the anti-obesity activity of the V. amurensis root. These results provide important new insight into the potential potent anti-adipogenic effect of the V. amurensis root and illustrate that one of the main compounds involved in this effect is oleanolic acid.