Conjugated linoleic acid(CLA) is a naturally occuring group of derivatives of linoleic acid found in beef and dairy products. CLA has reported to reduce body fat. This study was designed to observe the effect of CLA supplementation on fat accumulation and degradation in male Sprague Dawley rats. Seventy two rats, weighing 150-180g, were divided into 2 groups according to the types of dietary fat(beef tallow or fish oil) and then each group was divided into 2 groups depending on CLA supplementation, i.e., BT, BT-CLA, FO, FO-CLA. All rats were fed experimental diet containing total fat at 12%(w/w) including CLA at 1% for 30 weeks. At 30 weeks, rats were sacrificed to measure TG, free fatty acid level in plasma, TG, lipogenic enzymes in lever and fat cell size, LPL and HSL activities in epididymal fat fad. Fish oil supplemented with CLA diet showed significant reduction in the food efficiency and weight in 30 weeks-fed rats. CLA supplement did not effect on plasma TG, hepatic TG levels and lipogenic enzymes activities in rats, but, fish oil significantly reduced, The LPL and HSL activities did not affected by CLA supplement and n-3 fatty acid rich fish oil. In conclusion, the results suggest that CLA supplement was not a proper way to reduce the fat accumulation in Sprague Dawley rats. Fish oil supplemented with CLA might better way to reduce the body fatness than fish oil itself. Therefore, It is recommended that further study be performed related to physiological and biochemical effects of CLA supplementation and n-3 fatty acid in rats for the reduction of body fatness.(Korean J Nutrition 34(4) : 367∼374, 2001)
This research was conducted to investigate the physiological consequences of undernourished yak. Twelve Maiwa yak ($110.3{\pm}5.85kg$) were randomly divided into two groups (baseline and starvation group). The yak of baseline group were slaughtered at day 0, while the other group of yak were kept in shed without feed but allowed free access to water, salt and free movement for 9 days. Blood samples of the starvation group were collected on day 0, 1, 2, 3, 5, 7, 9 and the starved yak were slaughtered after the final blood sample collection. The liver and muscle glycogen of the starvation group decreased (p<0.01), and the lipid content also decreased while the content of moisture and ash increased (p<0.05) both in Longissimus dorsi and liver compared with the baseline group. The plasma insulin and glucose of the starved yak decreased at first and then kept stable but at a relatively lower level during the following days (p<0.01). On the contrary, the non-esterified fatty acids was increased (p<0.01). Beyond our expectation, the ketone bodies of ${\beta}$-hydroxybutyric acid and acetoacetic acid decreased with prolonged starvation (p<0.01). Furthermore, the mRNA expression of lipogenetic enzyme fatty acid synthase and lipoprotein lipase in subcutaneous adipose tissue of starved yak were down-regulated (p<0.01), whereas the mRNA expression of lipolytic enzyme carnitine palmitoyltransferase-1 and hormone sensitive lipase were up-regulated (p<0.01) after 9 days of starvation. The phosphoenolpyruvate carboxykinase and pyruvate carboxylase, responsible for hepatic gluconeogenesis were up-regulated (p<0.01). It was concluded that yak derive energy by gluconeogenesis promotion and fat storage mobilization during starvation but without ketone body accumulation in the plasma.
We evaluated the inhibitory effect of Pueraria lobata root ethanol extract (PLREE) on lipid accumulation during 3T3-L1 differentiation to adipocytes by measuring the intracellular expression of adipogenic, lipogenic, and lipolytic markers and lipid accumulation. The total polyphenol and flavonoid content of PLREE were 47 and 29 mg/g, respectively. The electron donating capacity of PLREE at $1,000{\mu}g/mL$ was 48.8%. Treatment of 3T3-L1 preadipocytes with 100, 250, or $500{\mu}g/mL$ PLREE for 8 days dose-dependently promoted the differentiation of 3T3-L1 cells. In contrast, the lipid content of PLREE-treated cells was significantly reduced by 7.8% (p < 0.05), 35.6% (p < 0.001), and 42.2% (p < 0.001) following treatment with 100, 250, and $500{\mu}g/mL$ PLREE, respectively, as compared to differentiated control cells. PLREE upregulated peroxisome proliferator-activated receptor ${\gamma}$ mRNA and protein, and sterol regulator element-binding protein-1c mRNA levels, but did not affect CCAAT/enhancer binding-protein ${\beta}$ and ${\alpha}$ mRNA levels. PLREE also downregulated acetyl-CoA carboxylase mRNA and protein, fatty acid synthase (FAS) protein, and leptin mRNA levels, but did not affect FAS mRNA expression. PLREE upregulated adipose triglyceride lipase mRNA and protein expression, and hormone-sensitive lipase (HSL) protein expression, but did not affect HSL mRNA expression. In conclusion, we found that PLREE enhanced adipogenesis, but reduced lipogenesis, resulting in decreased lipid accumulation in 3T3-L1 cells.
Purpose: Sour cherry (Prunus cerasus L.) contains abounding phytochemicals, such as polyphenols and anthocyanins, and has antioxidative effects. Adenosine monophosphate-activated protein kinase (AMPK) is a crucial regulator in enhancing the lipid metabolism. This study hypothesized that the intake of sour cherry affects AMPK signaling. Therefore, this study examined whether sour cherry regulates AMPK to balance the hepatic lipid metabolism and exert ameliorating effects. Methods: Male C57BL/6J mice had obesity induced with a 45% fat diet. The mice were divided into four groups: control (CON), high-fat diet (HFD), low percentage sour cherry powder (LSC), and high percentage sour cherry powder (HSC). The mice in the sour cherry groups were fed 1% sour cherry or 5% sour cherry in their respective diets for 12 weeks. Results: The body weight, visceral fat weight, and lipid droplet size significantly decreased in the treatment groups. The serum and hepatic triglyceride and total cholesterol levels improved significantly in the HSC group. The low-density lipoprotein cholesterol levels were also reduced significantly, whereas the high-density lipoprotein cholesterol levels were increased significantly in both treatment groups. The sterol regulator binding protein-1c and fatty acid synthase expression levels as fatty acid synthesis-related enzymes were significantly lower in the treatment groups than in the high-fat diet group. Furthermore, the adipose triglyceride lipase and hormone-sensitive lipase expression levels as lipolytic enzyme activity and AMPK/acetyl-CoA carboxylase/carnitine palmitoyltransferase-1 as fatty acid β-oxidation-related pathway were upregulated significantly in both sour cherry groups. Conclusions: These results show that sour cherry intake improves hepatic lipid synthesis and chronic diseases by activating AMPK signaling. Therefore, this study suggests that phytochemical-rich sour cherry can be developed as a healthy functional food.
Hyun Sook Lee;Jae In Jung;Jung Soon Hwang;Myeong Oh Hwang;Eun Ji Kim
Nutrition Research and Practice
/
v.17
no.6
/
pp.1043-1055
/
2023
BACKGROUND/OBJECTIVES: The fruit of Cydonia oblonga Miller (COM) is used traditionally in Mediterranean region medicine to prevent or treat obesity, but its mechanism of action is still unclear. Beyond a demonstrated anti-obesity effect, the fruit was tested for the mechanism of adipogenesis in 3T3-L1 preadipocytes. MATERIALS/METHODS: 3T3-L1 preadipocytes were cultured for 8 days with COM fruit extract (COME) at different concentrations (0-600 ㎍/mL) with adipocyte differentiation medium. The cell viability was measured using an MTT assay; triglyceride (TG) was stained with Oil Red O. The expression levels of the adipogenesis-related genes and protein expression were analyzed by reverse transcription polymerase chain reaction and Western blotting, respectively. RESULTS: COME inhibited intracellular TG accumulation during adipogenesis. A COME treatment in 3T3-L1 cells induced upregulation of the adenosine monophosphate-activated protein kinase (AMPK)α phosphorylation and downregulation of the adipogenic transcription factors, such as sterol regulatory element-binding protein 1c, peroxisome proliferator-activated receptor γ, and CCAAT/enhancer binding protein α. The COME treatment reduced the mRNA expression of fatty acyl synthetase, adenosine triphosphate-citrate lyase, adipocyte protein 2, and lipoprotein lipase. It increased the mRNA expression of hormone-sensitive lipase and carnitine palmitoyltransferase I in 3T3-L1 cells. CONCLUSIONS: COME inhibits adipogenesis via the AMPK signaling pathways. COME may be used to prevent and treat obesity.
Lakshi A. Dayarathne;Jasmadi;Seok-Chun Ko;Mi-Jin Yim;Jeong Min Lee;Ji-Yul Kim;Gun-Woo Oh;Dae-Sung Lee;Won-Kyo Jung;Sei-Jung Lee;Jae-Young Je
Journal of Microbiology and Biotechnology
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v.34
no.8
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pp.1688-1697
/
2024
The current study aimed to determine whether Strongylocentrotus intermedius (S. intermedius) extract (SIE) exerts anti-obesity potentials employing 3T3-L1 cells as in vitro model. Herein we reported that treatment of SIE for 6 days reduced lipid accretion and triglyceride content whereas it increased the release of free glycerol. The inhibited lipid accumulation and induced lipolysis were evidenced by the downregulation of lipogenesis proteins, such as fatty acid synthase and lipoprotein lipase, and the upregulation of hormone-sensitive lipase expression. Furthermore, the downregulation of adipogenic transcription factors, including peroxisome proliferator-activated receptor gamma, CCAAT/enhancer-binding protein α, and sterol regulatory element-binding protein 1, highlights that reduced lipid accumulation is supported by lowering adipocyte differentiation. Additionally, treatment activates brown adipocyte phenotype in 3T3-L1 cells by inducing expression of brown adipose tissue-specific proteins, such as uncoupling protein 1 and peroxisome proliferator-activated receptor-γ coactivator 1α. Moreover, SIE induced the phosphorylation of AMP-activated protein kinase (AMPK). The pharmacological approach using AMPK inhibitor revealed that the restraining effect of SIE on adipogenesis and promotion of adipocyte browning were blocked. In GC-MS analysis, SIE was mainly composed of cholest-5-en-3-ol (36.71%) along with saturated and unsaturated fatty acids which have favorable anti-obesity potentials. These results reveal that SIE has the possibility as a lipid-lowering agent for the intervention of obesity.
The archaeon Sulfolobus solfataricus P1 carboxylesterase is a thermostable enzyme with a molecular mass of 33.5 kDa belonging to the mammalian hormone-sensitive lipase (HSL) family. In our previous study, we purified the enzyme and suggested the expected amino acids related to its catalysis by chemical modification and a sequence homology search. For further validating these amino acids in this study, we modified them using site-directed mutagenesis and examined the activity of the mutant enzymes using spectrophotometric analysis and then estimated by homology modeling and fluorescence analysis. As a result, it was identified that Ser151, Asp244, and His274 consist of a catalytic triad, and Gly80, Gly81, and Ala152 compose an oxyanion hole of the enzyme. In addition, it was also determined that the cysteine residues are located near the active site or at the positions inducing any conformational changes of the enzyme by their replacement with serine residues.
Ji Hyun Kim;Sanghyun Lee;Hyun Young Kim;Eun Ju Cho
International Journal of Molecular Medicine
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v.45
no.2
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pp.589-596
/
2020
Acer okamotoanum is reported to have various antioxidant, anti-inflammatory and beneficial immune system effects. The anti-adipocyte differentiation effects and mechanisms of the ethyl acetate (EtOAc) fraction of an A. okamotoanum extraction was investigated in 3T3-L1 adipocyte cells. Treatment with differentiation inducers increased the level of triglycerides (TGs) in 3T3-L1 adipocyte cells compared with an untreated control. However, the EtOAc fraction of A. okamotoanum significantly decreased TGs. Treatment with 1, 2.5 and 5 ㎍/ml showed weak activity, but TG production was inhibited at 10 ㎍/ml compared with the control. In addition, A. okamotoanum caused a significant downregulation of proteins related to adipogenesis, such as γ-cytidine-cytidine-adenosine-adenosine-thymidine/enhancer binding protein-α, -β and peroxisome proliferator-activated receptor-γ, compared with the untreated control. Furthermore, A. okamotoanum significantly upregulated lipolysis related protein, hormone-sensitive lipase and the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK). Therefore, these results indicate that A. okamotoanum suppressed adipogenesis and increased lipolysis and the activation of AMPK, suggesting a protective role in adipocyte differentiation.
A trial was conducted to investigate the effect of dietary NMA on several growth associated hormones and fat metabolism in finishing pigs. A total of 84 crossbred finishing pigs (average initial BW of $56{\pm}$0.37kg) were divided into 6 pens, 14 pigs per pen (7 gilts and 7 barrows per pen). 3 pens of pigs were fed with control diet (corn-soybean meal) and the others were fed control diet addition with 50 mg/kg NMA. During the trial, all pigs were given free access to feed and water. After 44 days trial, 8 pigs from each treatment (4 gilts and 4 barrows, weight similar to average group weight, $86.94{\pm}0.71kg$ for control group, and $90.55{\pm}1.51kg$ for NMA treated group) were sacrificed to collect the sample of the liver, longissimus muscle, subcutaneous fat (10th rib). The addition of NMA in diet increased the IGF-I, Insulin, T3, T4 levels in serum by 50.68% (p<0.05), 38.36% (p<0.05), 123.33% (p<0.01), 60.58% (p<0.03), respectively. Meanwhile, IGF-I level in the liver and the muscle were increased with 17.83% (p<0.03) and 26.00% (p<0.03) with addition of NMA. The data from subcutaneous fat (10th rib) analysis showed that supplement of 50 mg/kg NMA decreased the total activities of malic dehydrogenase (MDH) by 20.54% (p<0.05), glucose-6- phosphate dehydrogenase (G-6-DPH) by 16.97% (p<0.05), and decreased the specific activities of MDH and G-6-DPH by 37.46% (p<0.01) and 35.06% (p<0.01), respectively. The hormone sensitive lipase (HSL) total activity was increased by 25.00% (p<0.05) in NMA treated pigs. These results indicated that addition of 50 mg/kg NMA to diet can induce the endocrine great change in finishing pigs, furthermore, inhibit the fat synthesis through suppressing lipogenic enzymes and promote the fat degradation by elevating HSL activity in finishing pigs.
Kim, Sung-Ok;Kim, Mi-Ryeo;Hwang, Kyung-A;Park, No-Jin;Jeong, Ji-Suk
Journal of the Korean Society of Food Science and Nutrition
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v.46
no.4
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pp.401-408
/
2017
Salvia plebeia R. Br. (Lamiaceae) has been used in folk medicines in Asian countries, including Korea and China, to treat inflammatory diseases. The focus of our research was on the anti-adipogenic activity of ethanol extract from Salvia plebeia R. Br. (SPE) in 3T3-L1 adipocytes. This study investigated inhibition of differentiation and lipogenesis upon SPE treatment in 3T3-L1 cells. The results reveal that SPE at non-cytotoxic concentration significantly suppressed triglyceride accumulation and reduced expression of peroxisome proliferator-activated receptor gamma, CCAAT/enhancer-binding protein-alpha, and sterol regulatory element-binding protein as adipogenic transcription factors in 3T3-L1 adipocytes compared to non-treated control cells. Inducible phosphorylation of AMP-activated protein kinase, acetyl CoA carboxylase, and hormone-sensitive lipase as well as carnitine palmitoyltransferase-1 mRNA expression increased upon SPE treatment, which suppressed expression of fatty acid synthase. In conclusion, these results demonstrate that SPE can inhibit expression of adipogenic genes in 3T3-L1 adipocytes. Our study suggests that SPE has potential anti-obesity effects and is a novel therapeutic functional agent with anti-adipogenic activity via reduction of lipogenesis.
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