Alcohol-induced fatty liver (steatosis) results from excessive generation of reducing equivalents by ethanol metabolism. Generally, chronic ethanol treatment causes hepatosteatosis by regulating sterol regulatory element-binding protein 1c (SREBP-1c), which increases the synthesis of hepatic lipids. The effect of ethanol on SREBP-1c is mediated through mammalian sirtuin-1 (SIRT-1), a NAD+-dependent protein deacetylase that regulates hepatic lipid metabolism. Ginseng is a widely used herbal medicine that is used in Asia for its anti-diabetes and anti-obesity effects. The pharmacological and therapeutic effects of ginseng are primarily produced by bioactive constituents known as ginsenosides. Here, we examined the regulatory effects of Korean red ginseng (KRG) extracts on SREBP-1c and SIRT-1 on lipid homeostasis in AML-12 mouse hepatocytes. AML-12 cells were treated with ethanol and/or KRG extracts (0 - 1,000 μg/ml). Lipid droplets were assayed using Oil red O staining, and western blotting was used to measure SIRT-1 and SREBP-1 expression. Treatment with KRG extracts restored SIRT-1 expression and reduced SREBP-1c expression in ethanol-treated cells. We also showed that KRG extract and ginsenosides Rb2 and Rd significantly decreased SREBP-1 acetylation in ethanol-treated cells. These results show that treatment with KRG extract and its active ginsenoside constituents Rb2 and Rd protected against alcohol-related hepatosteatosis via regulation of SIRT-1 and downstream acetylation of SREBP-1c, which altered hepatic lipid metabolism.
The capacity for liver regeneration involves a variety of nutritional factors. Vitamin C has multiple metabolic and antioxidant functions. In this study, we investigated the role of vitamin C in liver regeneration following hepatectomy in senescence marker protein (SMP)-30 knockout (KO) mice. Partial hepatectomy was performed by resecting the median and left lateral lobes of mice. Vitamin C accelerated liver recovery in SMP30 KO mice treated with vitamin C (KV). The livers of the KV mice exhibited lower levels of aspartate aminotransferase and lower injury than those of the KO mice. Increased type II transforming growth factor-β receptor (TGF-βRII)-mediated regeneration signaling was accompanied by HGF and cMet in the KV but not the KO mice. Consistent with this, the expression of cell cycle regulatory proteins, including cyclin D1 and proliferating cell nuclear antigen (PCNA), increased rapidly in the KV mice. Enhanced activation of ERK and GSK-3β proteins and a significantly increased number of binuclear hepatocytes were also detected in the livers of the KV mice. Moreover, the KV mice synthesized the highest levels of albumin. These data suggest that treating SMP30 knockout mice with vitamin C resulted in earlier recovery and liver regeneration by activation of the regeneration system.
Journal of the Korean Society of Food Science and Nutrition
/
v.24
no.5
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pp.713-719
/
1995
These studies were carried out to investigate the effects of Puerariae radix catechins(PRC) administration on the biochemical parameters of liver function in liver of carbon tetrachloride(CCl4)-treated rats. Thirty six healthy Sprague-Dawley rats weighing about 120g were used for this experiment and divided intot he following 3 groups : normal control group(NCON), $CCl_4$ control group(CCON), PRC treated group(PRC). Fifty percent $CCl_4$ in oil was administered(I.P.) by 2ml per kg body weight two times a week for 3 weeks. PRC treated groups were administered orally at the leaves of 1% per day in distilled water for 8 weeks. Lipid hydroperoxides were analyzed by using chemiluminescence-high performance liquid chromatography(CL-HPLC) method as a phosphatidylcholine hydroperoxide value(PCOOH) in liver tissues. $CCl_4$ treatment significantly(p<0.05) resulted in an increase in GPT & GOT activities and liver hydroperoxide values comparing with those of the untreated control, while administration of PRC to the $CCl_4-treated$ rats significantly(p<0.001) decreased GPT & GOT activities and liver hydroperoxide value. Their ultrastructual changes of hepatocellular organelles were shown to clarify the morphologic nature of protective effects of PRC on hepatocytic injuries. $CCl_4$ treatment observed to change the ultrastructual nature of outer membrane of hepatocytes. However, the hepatic changes on PRC treatment to $CCl_4$ group was not found. PRC administration may inhibit the formatiion of liver lipid hydroperoxides in vivo and were very effective in recovering the liver function in $CCl_4-treated$ rats.
Kim, Seok;Jung, Jaehoon;Kim, Hwajin;Heo, Rok Won;Yi, Chin-Ok;Lee, Jung Eun;Jeon, Byeong Tak;Kim, Won-Ho;Hahm, Jong Ryeal;Roh, Gu Seob
The Korean Journal of Physiology and Pharmacology
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v.18
no.4
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pp.333-339
/
2014
Exendin-4 (Ex-4), a glucagon-like peptide-1 receptor (GLP-1R) agonist, has been known to reverse hepatic steatosis in ob/ob mice. Although many studies have evaluated molecular targets of Ex-4, its mechanism of action on hepatic steatosis and fibrosis has not fully been determined. In the liver, glucose transporter 4 (GLUT4) is mainly expressed in hepatocytes, endothelial cells and hepatic stellate cells (HSCs). In the present study, the effects of Ex-4 on GLUT4 expression were determined in the liver of ob/ob mice. Ob/ob mice were treated with Ex-4 for 10 weeks. Serum metabolic parameters, hepatic triglyceride levels, and liver tissues were evaluated for hepatic steatosis. The weights of the whole body and liver in ob/ob mice were reduced by long-term Ex-4 treatment. Serum metabolic parameters, hepatic steatosis, and hepatic fibrosis in ob/ob mice were reduced by Ex-4. Particularly, Ex-4 improved hepatic steatosis by enhancing GLUT4 via GLP-1R activation in ob/ob mice. Ex-4 treatment also inhibited hepatic fibrosis by decreasing expression of connective tissue growth factor in HSCs of ob/ob mice. Our data suggest that GLP-1 agonists exert a protective effect on hepatic steatosis and fibrosis in obesity and type 2 diabetes.
One of therapeutics in liver disease (morbus wilson) is D-penicillamin (D-pen: D-3-mercapto-valin). Especially the cross-linking of collagen molecules could be inhibited by D-pe n in extracellular space. In this study we investigated the antifibrotic effects of D-pen in rats that were induced the liver fibrosis by bile duct ligation and scission (BDL/S). Rats were treated for 4 weeks with D-pen after BDL/S operation or sham operation. The balance between fibrogenesis-marker (PNIIIP) and the fibrolysis-maker (PNIVP) were observed in sera by RIA (radioimmunoassay), and the parameter of collagen deposition in liver tissue (hydroxyproline: HYP) was measured by colorimetry. The weight of liver in BDL/S operated group was increased significantly in compared with sham operation group (15.2g${\pm}$1.1, vs 11.9g${\pm}$3.9: p<0.005, p<0.05). The rats group treated by D-pen showed the lower level of PNIIIP (6.7ng/ml${\pm}$1.5, vs 9.5ng/ml${\pm}$2.8) and the higher value of PIVCP (14.0ng/ml${\pm}$1.9, vs 7.9ng/ml${\pm}$1.5) in sera that compared to untreated rats. The content of HYP was decreased by 141% in BDL/S with D-pen treated group than that of it in BDL/S group. No correlation was revealed between collagen parameters in sera and HYP in liver tissue of BDL/S operated and D-pen treated rats. The group treated with D-pen showed the lower value of clinical biochemistry parameters (GOT: glutamate oxalacetate transaminase, Total-Bilirubin) in compared with only BDL/S operated rats, but the value of GPT (glutamate pyruvate transaminase) and Alkaline phosphatase in two BDL/S groups was nearly same. In the histological finding, we observed mild bile duct proliferation, weak inflammation and fibrosis in BDL/S with D-pen treated group, but BDL/S operated group showed the formation of septum (island of hepatocytes), massive bile duct proliferation. This result represents that the BDL/S operation induces liver fibrosis (cirrhosis) in 4 weeks, and D-pen inhibits the synthesis of collagen weakly and stimulates the degradation of collagen in the extracellular space. We conclude that the monitoring of PNIIIP, PIVCP in sera is useful parameter for screening of antifibrotic effect, and D-pen delay the liver fibrosis.
The antitumor effect of 柴胡(Bupleuri Radix : BP), 茵陳(Artemisiae capillaris Herba; ACH) 및 蒲公英(Taraxaci Herba; TH) and 蒲公英 EE層(Ethyl ether layer of TH; EETH) on human hepatocytes such as Hep G2, PLC and Hep 3B, and synergistic action with the anticancer drugs, that is, mitomycin(MMC), cisplatin(CPT) and 5-fluorouracil(5-FU) were studied by the method of MTT. The results were obtained as follows: 1. $IC_{50}$ against Hep G2, PLC and Hep 3B was $15.5{\mu}g/ml$, $25.4{\mu}g/ml$ and 31.25 in MMC, $92.5{\mu}g/ml$, $50.2{\mu}g/ml$ and $62.5{\mu}g/ml$ in CPT and $125{\mu}g/ml$ in 5-FU respectively. 2. Cytotoxic effect on Hep G2 was obvious in BP-treated group, synergistic action was most effective in TH-treated group or with MMC. 3. Cytotoxic effect on Hep 3B was obvious in ACH-treated group, synergistic action was most effective in ACH-treated group or with MMC. 4. Cytotoxic effect on PLC was obvious in ACH-treated group, synergistic action was most effective in TH-treated group or with MMC. From above results it was concluded that ACH showed the best antitumor effect against PLC and Hep 3B, BP aganst Hep G2 and also synergistic effect was most effective with MMC, which indicates that it is necessary to seperate the antitumor substances in ACH.
Present study aimed to investigate the radioprotective effects of propolis feeding on rat tissues damaged by X-ray irradiation. It was shown that the number of white blood cell in X-ray irradiated group supplemented with propolis increased as much to those of the control group and also the GOT activities among the blood components were decreased after propolis feeding. The mineral contents such as Mg, Fe, Ca, Mn, Cu, Mo, Ni, As in liver were increased as compared with those of the control group but maintained lower level than those of only irradiated groups, implying that the propolis feeding elevated the recovery capability of white blood cell effectively and propolis have a potential resistance to cell damage by X-ray. According to histological observations of the testis, intestine and liver tissues which are irradiated after feeding propolis, the numbers of damaged undifferentiated cells were decreased in testis and the shape of the goblet cells and inner and outer muscular layers in intestine were restored to the original state and the hepatocytes and interlobular veins were shown intact in liver, suggesting that propolis has a potential capacity to restore cell shapes or resist deformation of cell.
Journal of the Korean Society of Food Science and Nutrition
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v.34
no.6
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pp.814-820
/
2005
This study was designed to determine the effect of chitosan on in vivo lipid metabolism in male Sprague-Dawley rats treated with ethanol. Rats were divided into four groups and reared for 6 weeks: E group ($35\%$ of total calories from ethanol), EC I group ($ethanol+0.5\%$ of chitosan), EC II group ($ethanol +1\%$ of chitosan) and control group (dextrin as much as ethanol treated). The levels of serum total cholesterol (TC) and LDL-cholesterol (LDL-C), GOT and GPT in plasma, and triglyceride (TG) in liver were remarkably increased in the rats treated with ethanol. However, the treatment of $1\%$ chitosan significantly lowered those parameter levels. In particular the values of r-HDL (the ratio of HDL-C to TC) in the rats fed in combination with ethanol and chitosan were relatively higher than that of the E group. The increased lipid droplets were observed in the hepatocytes of the rats treated with ethanol, but chitosan treatment reduced in the number and the size of the lipid droplets. These results suggest that chitosan improve in vivo lipid metabolism and Potentially protect hepatotoxicity of the rat liver treated with ethanol.
Kim, Jin-Do;Do, Jeong-Wan;Choi, Hye-Sung;Seo, Jung-Soo;Jung, Sung-Hee;Jo, Hyae-In;Park, Myung-Ae;Lee, Nam-Sil;Park, Sung-Woo
Korean Journal of Environmental Biology
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v.31
no.4
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pp.486-492
/
2013
Recently, a new disease showing symptoms such as epidermal exfoliation and muscular necrosis occurred in cultured Korean catfish. Although the mortality of fishes was low but the economic damages owing to loss of commercial value were severe. The authors isolated the causative agent from diseased fish and observed pathological changes both in naturally and artificially infected fish. The causative bacteria was identified as Aeromonas veronii. Subsequently we observed the daily death and pathological symptoms of artificially infected fish with Aeromonas veronii. Symptoms of artificially infected fish were similar to those of naturally infected fish and all fish died within 7 days after infection. Histopathological changes on the naturally infected fish revealed severe congestion and necrotic degeneration in the liver, spleen and kidney. Some bacterial aggregates with inflammatory degeneration were observed in the heart, and congestion and fibrosis in the lamina propria of digestive tube were predominant. In artificially infected fish, skin erosion and necrotic degeneration of muscle tissue around injected region were particularly manifested. Degeneration of hepatocytes in liver and hyalic degeneration around ellipsoids in spleen were partially observed. However, there were no predominant signs in digestive tube in artificially infected fish.
Kim, Eunju;Kim, Yoo-Sun;Kim, Kyung-Mi;Jung, Sangwon;Yoo, Sang-Ho;Kim, Yuri
Nutrition Research and Practice
/
v.10
no.1
/
pp.11-18
/
2016
BACKGROUND/OBJECTIVES: Type 2 diabetes (T2D) is more frequently diagnosed and is characterized by hyperglycemia and insulin resistance. $\small{D}$-xylose, a sucrase inhibitor, may be useful as a functional sugar complement to inhibit increases in blood glucose levels. The objective of this study was to investigate the anti-diabetic effects of $\small{D}$-xylose both in vitro and stretpozotocin (STZ)-nicotinamide (NA)-induced models in vivo. MATERIALS/METHODS: Wistar rats were divided into the following groups: (i) normal control; (ii) diabetic control; (iii) diabetic rats supplemented with a diet where 5% of the total sucrose content in the diet was replaced with $\small{D}$-xylose; and (iv) diabetic rats supplemented with a diet where 10% of the total sucrose content in the diet was replaced with $\small{D}$-xylose. These groups were maintained for two weeks. The effects of $\small{D}$-xylose on blood glucose levels were examined using oral glucose tolerance test, insulin secretion assays, histology of liver and pancreas tissues, and analysis of phosphoenolpyruvate carboxylase (PEPCK) expression in liver tissues of a STZ-NA-induced experimental rat model. Levels of glucose uptake and insulin secretion by differentiated C2C12 muscle cells and INS-1 pancreatic ${\beta}$-cells were analyzed. RESULTS: In vivo, $\small{D}$-xylose supplementation significantly reduced fasting serum glucose levels (P < 0.05), it slightly reduced the area under the glucose curve, and increased insulin levels compared to the diabetic controls. $\small{D}$-xylose supplementation enhanced the regeneration of pancreas tissue and improved the arrangement of hepatocytes compared to the diabetic controls. Lower levels of PEPCK were detected in the liver tissues of $\small{D}$-xylose-supplemented rats (P < 0.05). In vitro, both 2-NBDG uptake by C2C12 cells and insulin secretion by INS-1 cells were increased with $\small{D}$-xylose supplementation in a dose-dependent manner compared to treatment with glucose alone. CONCLUSIONS: In this study, $\small{D}$-xylose exerted anti-diabetic effects in vivo by regulating blood glucose levels via regeneration of damaged pancreas and liver tissues and regulation of PEPCK, a key rate-limiting enzyme in the process of gluconeogenesis. In vitro, $\small{D}$-xylose induced the uptake of glucose by muscle cells and the secretion of insulin cells by ${\beta}$-cells. These mechanistic insights will facilitate the development of highly effective strategy for T2D.
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