• Journal of Biomedical Engineering Research
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• v.43 no.1
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• pp.1-10
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• 2022

Non-alcoholic fatty liver disease(NAFLD) is excessive hepatic lipid accumulation mainly caused by obesity. This study aimed to evaluate whether micro-current stimulation(MCS) could modulate lipid metabolism regarding the Sirt1/AMPK pathway, fatty acid β-oxidation pathway, and lipolysis and lipogenesis-related factors in FL83B cells. For the NAFLD cell model, FL83B cells were treated with oleic acid for lipid accumulation. MCS were stimulated for 1 hr and used frequency 10 Hz, duty cycle 50%, and biphasic rectangular current pulse. The intensity of MCS was divided into 50, 100, 200, and 400 ㎂. Through the results of Oil red O staining, it was confirmed that MCSs with the intensity of 200 ㎂ and 400 ㎂ significantly reduced the degree of lipid droplet formation. Thus, these MCS intensities were applied to western blot analysis. Western blot analysis was performed to analyze the effects of MCS on lipid metabolism. MCS with the intensity of 400 ㎂ showed that significantly activated the Sirt1/AMPK pathway, a key pathway for regulating lipid metabolism in hepatocytes, and fatty acid β-oxidation-related transcription factors. Moreover, it activated the lipolysis pathway and suppressed lipogenesis-related transcription factors such as SREBP-1c, FAS, and PPARγ. In the case of MCS with the intensity of 200 ㎂, only PGC1α and SREBP-1c showed significant differences compared to cells treated only with oleic acid. Taken together, these results suggested that MCS with the intensity of 400 ㎂ could alleviate hepatic lipid accumulation by modulating lipid metabolism in hepatocytes.

• Journal of Nutrition and Health
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• v.27 no.5
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• pp.442-450
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• 1994

The purpose of this study was to determine the effects of 2-AAF injection time on hepatic lipid peroxide metabolism and cytochrome P450 content in Sprague-Dawley rats fed diets containing high amounts of vegetable oils or animal fats(15%, w/w). Fifty mg of 2-AAF/kg of body weight/day was injected in PEG 300 intraperitonially for 3 consecutive days after 4 or 8 weeks to rats fed corn oil(CO) or lard(LA) diet. The contents of lipid peroxide and cytochrome P450, and the activities of superoxide dismutase(SOD), glutathione peroxidase(GSH-peroxidase) and glutathione S-transferase(GSH-S-transferase) were determined in hepatic microsomal or cytosolic fraction. Microsomal thiobarbituric acid reactive substances(TBARS) and cytochrome P450 contents increased in Co group injected 2-AAF after 4weeks. Cytosolic SOD activity increased in CO group injected 2-AAF after 4 weeks and in LA group injected 2-AAF after 4 or 8 weeks. Cytosolic GSH-S-transferase activity increased in LA group compared to CO group without 2-AAF injection. GSH-S-transferase activity increased in CO group injected 2-AAF after 4 or 8 weeks and in LA group injected 2-AAF after 4 weeks. Therefore, it may be suggested that 2-AAF injection increase the contents of lipid peroxide or cytochrome P450, and detoxifying enzyme activities in rats fed CO diet for short period and in rats fed LA diet for longer period.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1171-1176
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• 2003

The effects of dietary conjugated linoleic acid (CLA) on lipid concentrations and fatty acid composition of various tissues were studied in young chicks. From 7 days of age, a total of 160 chicks were divided into 4 groups, placed into 4 pens per group (10 birds per pen) and fed one of four experimental diets containing 6% tallow (TO 6%), 4% tallow plus 2% CLA (TO 4%-CLA 2%), 2% tallow plus 4% CLA (TO 2%-CLA 4%) or 6% CLA (CLA 6%) for 3 weeks. There were no significant differences in growth performances and the relative weights of various organs, but relative liver weight of chicks fed dietary CLA at 4 and 6% levels was significantly higher (p<0.05) than that of TO 6% group. The chemical compositions of leg muscle were not affected by CLA feeding. However, hepatic total lipid of chicks fed 6% CLA diet was significantly higher (p<0.05) than those of TO 6% and TO 4%-CLA 2% groups. The concentrations of various lipid fractions in serum were not affected by CLA feeding. With the increase in dietary CLA levels, cis 9-trans 11 CLA, trans 10-cis 12 CLA and total CLA of leg muscle increased linearly. The relative proportions of C18:1 $\omega$ -9 and C20:4 $\omega$-6 fatty acids in the leg muscles of chicks fed the CLA containing diets were significantly lower (p<0.05) than those of TO 6% group. These results indicate that the levels of CLA isomers were increased linearly in dose-dependent manner after feeding of synthetic CLA source. But it was also observed that excessive amount of dietary CLA resulted in the possible adversely effects, such as increase of liver weight, hepatic lipid accumulation and serum GOT level.

• Preventive Nutrition and Food Science
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• v.21 no.3
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• pp.171-180
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• 2016

Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent liver diseases associated with an altered lifestyle, besides genetic factors. The control and management of NAFLD mostly depend on lifestyle modifications, due to the lack of a specific therapeutic approach. In this context, we assessed the effect of carrot juice on the development of high fructose-induced hepatic steatosis. For this purpose, male weanling Wistar rats were divided into 4 groups, fed either a control (Con) or high fructose (HFr) diet of AIN93G composition, with or without carrot juice (CJ) for 8 weeks. At the end of the experimental period, plasma biochemical markers, such as triglycerides, alanine aminotransferase, and ${\beta}$-hydroxy butyrate levels were comparable among the 4 groups. Although, the liver injury marker, aspartate aminotransferase, levels in plasma showed a reduction, hepatic triglycerides levels were not significantly reduced by carrot juice ingestion in the HFr diet-fed rats (HFr-CJ). On the other hand, the key triglyceride synthesis pathway enzyme, hepatic stearoyl-CoA desaturase 1 (SCD1), expression at mRNA level was augmented by carrot juice ingestion, while their protein levels showed a significant reduction, which corroborated with decreased monounsaturated fatty acids (MUFA), particularly palmitoleic (C16:1) and oleic (C18:1) acids. Notably, it also improved the long chain n-3 polyunsaturated fatty acid, docosahexaenoic acid (DHA; C22:6) content of the liver in HFr-CJ. In conclusion, carrot juice ingestion decreased the SCD1-mediated production of MUFA and improved DHA levels in liver, under high fructose diet-fed conditions. However, these changes did not significantly lower the hepatic triglyceride levels.

• Journal of Nutrition and Health
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• v.56 no.6
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• pp.641-654
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• 2023

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.

• Nutrition Research and Practice
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• v.9 no.5
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• pp.489-495
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• 2015

BACKGROUND/OBJECTIVES: The present study was conducted to investigate the effects of dried Momordica charantia aqueous extracts (MCA) and ethanol extracts (MCE) on obesity and lipid profiles in mice fed a high-fat diet. MATERIALS/METHODS: Forty two ICR mice were randomly divided into six groups. The normal group was fed a basal diet, and other groups were fed a 45% high-fat diet (HFD) for 7 weeks. The normal and HFD groups were also orally administered distilled water each day for 7 weeks. The remaining groups received Momordica charantia extract (0.5 or 1.0 g/kg/day MCA, and 0.5 or 1.0 g/kg/day MCE). In order to measure the anti-obesity and lipid profile improvement effects, body and visceral tissue weight, lipid profiles, plasma insulin levels, hepatic malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were measured. RESULTS: Both MCA and MCE significantly decreased body and visceral tissue weight relative to those of the HFD group (P < 0.05). Additionally high doses of MCE and MCA significantly reduced the plasmatic insulin levels compared to the HFD groups (P < 0.05) to concentrations comparable to those found in the normal group. MCA and MCE supplementation also significantly modulated the lipid profiles in plasma, liver, and feces compared to mice fed the HFD (P < 0.05). Furthermore MCA and MCE significantly increased hepatic SOD activity, and reduced MDA generation in the liver of the HFD mice (P < 0.05). CONCLUSIONS: Results from the present study suggest that Momordica charantia extracts have anti-obesity effects and the ability to modulate lipid prolife of mice fed a HFD by suppressing body weight gain, visceral tissue weight, plasma and hepatic lipid concentrations, and lipid peroxidation along with increasing lipid metabolism.

• Biomedical Science Letters
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• v.13 no.2
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• pp.91-97
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• 2007

Obesity is defined as increased mass of adipose tissue, conferring a higher risk of cardiovascular and metabolic disorders such as diabetes, hyperlipidemia, and coronary heart disease. To get a better understanding of the role of a male sex hormone testosterone on obesity, we thus measured the effects of testosterone on white adipose tissue (WAT) mass, adipocyte histology and hepatic lipid accumulation in male castrated (CAST) C57BL/6J mice. Compared to male CAST control mice, testosterone-treated mice had the decreased WAT mass and the increased the number of adipocytes. Especially, histological data showed that the adipocyte size was reduced in a dose-dependent manner and was most effective at dose 150 $\mu$g per mouse for testosterone. In addition, the administration of testosterone resulted in the inhibition of hepatic lipid accumulation compared with control mice. Our results suggest that testosterone regulates adipocytes development and hepatic lipid metabolism, resulting in the prevention of obesity in male CAST mice.

• Journal of Nutrition and Health
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• v.31 no.2
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• pp.135-142
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• 1998

This study was undertaken to determine whether dehulled defatted flour has an effect on postprandial plasma lipoprotein composition, hepatic lipid composition, enzyme and hormone levels in rats. Control(casein) and experimental (dehulled defatted soy flour)diets were fed to rats for 7 weeks. all animals (S. D. rats, male) were sacrificed 2 hrs after the feeding of 5g of each diet. Defatted soy flour feeding significantly lowered postprandial plasma total cholesterol, chylomicron/VLDL-cholesterol, hepatic cholesterol and triglyceride(TG) as compared with casein feeding, whereas no significant effect on plasma TG was observed. Intestinal kipase activity was elevated , whereas trypsin activity was suppressed in the dehulled defatted soy flour group. Plasma glucagon, thyroid hormone and hepatic HMG-coA reductase levels were not affected by diet treatment. These results hypothesize that dehulled defatted soy flour affects cholesterol digestion and absorption in guts, thus delaying the appearance of chylomicron cholesterol in plasma or affecting the disappearance of chylomicron remnant to high-density-lipoprotein(HDL).

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.236-240
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• 1998

The effect of thyroid hormones on the hepatic xanthine oxidase activity was studied in rats after the intraperitoneal injections of comthyroid (triiodotyronine:thyroxine=1:4) at 0.3 mg/kg for 3 consecutive days. The aim of this study was to understand the precise mechanism of hyperthyroidism induced by oxidative stress. The concentration of lipid peroxides determined indirectly by the measurement of thiobarbituric acid reactants was increased in comthyroid treated rats. The hepatic glutathione content was decreased in comthyroid injected rat compared to the euthyroid state. It was also observed that the increment of xanthine oxidase activity has a profound role in oxygen radicals generation system in comthyroid treated rat. These findings suggest that the enhanced xanthine oxidase activity and depleting glutathione content in comthyroid treated rats result in pathophysiological oxidative stress including an increment of hepatic lipid peroxidation.

• Archives of Pharmacal Research
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• v.23 no.5
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• pp.495-500
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• 2000

We investigated whether S-adenosylmethionine (SAM) treatment improved ischemic injury using perfused rat liver after sequential periods of 24 h cold and 20 min re-warming ischemia. SAM (100 $\mu\textrm{mol/L}$) was added to University of Wisconsin (UW) solution and Ringers lactate solution. After cold and sequential warm ischemia, releases of lactate dehydrogenase (LDH) and purine nucleoside phosphorylase (PNP) markedly increased during repefusion. The increase in PNP was significantly reduced by SAM treatment. While the concentration of reduced glutathione (GSH) in ischemic livers significantly decreased, the concentration of glutathione disulfide (GSSG) increased. This decrease in GSH and increase in GSSG were suppressed by SAM treatment. Lipid peroxidation was elevated in cold and warm ischemic and reperfused livers, but this elevation was also prevented by SAM treatment. Hepatic ATP levels were decreased in the ischemic and reperfused livers to 42% of the control levels. However, treatment with SAM resulted in significantly higher ATP levels and preserved the concentration of AMP in ischemic livers. Our findings suggest that SAM prevents oxidative stress and lipid peroxidation and helps preserve hepatic energy metabolism.