• Asian-Australasian Journal of Animal Sciences
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• 제17권10호
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• pp.1378-1382
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• 2004

Zinc (Zn) is a micromineral and functions as a cofactor of many enzymes and its deficiency induces retardation of growth and dysfunction of the immune system in animals. This study was conducted to determine lipogenic activity of Zn in bovine intramuscular adipocytes. Preadipocytes were isolated from intramuscular fat depots of 26 month old Korean (Hanwoo) steers and cultured in media containing Zn. At confluence, the cells were treated with insulin, dexamethasone, and 1-methyl-3-isobutyl-xanthine to induce differentiation (accumulation of lipid droplets in cells). The sources of Zn were zinc chloride (${ZnCl}_2$) and zinc sulfate (${ZnSO}_4$), and the final concentrations of both Zn sources were 0, 5, 25, 50 and 100 ${\mu}$M. Glycerol-3-phosphate dehydrogenase (GPDH) activity, an index of adipocyte differentiation, was increased as the concentration of Zn in media increased showing the highest activity (25.74 ng/min/mg protein) at 25 ${\mu}$M of ${ZnSO}_4$. Supplementation of Zn during differentiation of bovine intramuscular adipocytes tended to decrease the production of nitric oxide (NO). Peroxisome proliferator-activated receptor gamma 2(PPAR$\gamma$2) gene expression was increased 10 days after differentiation induction. The current results indicate that Zn has a strong lipogenic activity in cultured bovine intramuscular adipocytes with remarkable suppression of NO production.

• Journal of Nutrition and Health
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• 제17권4호
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• pp.290-296
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• 1984

어유식이(魚油食餌)가 간장조직내 lipogenic enzyme의 활성도에 미치는 영향을 조사하고자 고등어유를 식이(食餌) 10%(w/w) 되게 먹이를 조제하여 13일동안 사육한 흰쥐의 간장조직의 glucose-6-phosphate dehydrogenase와 malic enzyme의 활성도는 lard를 섭취한 군(群)보다 $3{\sim}6$일의 섭취로 훨씬 저하되었으며 콩기름에 비하여는 같거나 또는 약간 낮은 값을 보였다. 고등어 또는 장어유를 어유(魚油)로 사용하여 먹이의 $0{\sim}10%$로 함량을 변화시키며 총지방량을 10%로 일정히 하고자 콩기름 또는 쇠기름을 배합유로 사용하였을 때 glucose-6-phosphate dehydrogenase의 활성은 어유(魚油)가 2 % 포함하였을 때부터 malic enzyme의 활성은 5% 포함하였을 때, 어유(魚油)를 포함하지 않은 군(群)에 비하여 감소를 보였다.

• 한국동물위생학회지
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• 제44권4호
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• pp.195-207
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• 2021

Species A rotaviruses (RVAs) replicate and assemble their immature particles within electron dense compartments known as viroplasms, where lipid droplets (LDs) interact with the viroplasm and facilitate viral replication. Despite the importance of LD formation in the life cycle of RVAs, the upstream molecules modulating LD formation remain unclear. This study aimed to find out the role of sterol regulatory element-binding proteins (SREBPs) in reprogramming of LD formation after RVA infection. Here, we demonstrate that RVA infection reprograms the sterol regulatory element-binding proteins (SREBPs)-dependent lipogenic pathways in virus-infected cells, and that both SREBP-1 and -2 transactivated genes, which are involved in fatty acid and cholesterol biosynthesis, are essential for LD formation. Our results showed that pharmacological inhibition of SREBPs using AM580 and betulin and inhibition of their downstream cholesterol biosynthesis (simvastatin for HMG-CoA reductase) and fatty acid enzymes (TOFA) negatively modulated the intracellular triacylglycerides and cholesterol levels and their resulting LD and viroplasm formations. Interestingly, pharmacological inhibition of SREBPs significantly reduced RVA protein synthesis, genome replication and progeny production. This study identified SREBPs-mediated lipogenic reprogramming in RVA-infected host cells, which facilitates virus replication through LD formation and its interaction with viroplasms, suggesting that SREBPs can be a potential target for the development of efficient and affordable therapeutics against RVA infection.

• Asian-Australasian Journal of Animal Sciences
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• 제17권11호
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• pp.1562-1569
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• 2004

The objective of this experiment was to determine the effects of n-3 polyunsaturated fatty acids (n-3 PUFAs)-enriched diet supplemented with different levels of $\alpha$-tocopherol on the activities of hepatic lipogenic-related enzymes and the contents of liver and plasma lipid fractions in laying Tsaiya ducks. A total of 180 30-wk-old laying Tsaiya ducks, at the beginning of peak production, were allotted into 6 treatments with 3 replicates each. Ducks were fed one of the 6 experimental diets, containing 4% tallow (control), and 4% fish oil supplemented with graded levels of $\alpha$-tocopheryl acetate ($\alpha$-tocopherol) at 0, 100, 200, 300 and 400 mg/kg, respectively, for 6 wks. Feed and water were supplied ad libitum throughout the experimental period. The results indicated that the n-3 PUFAsenriched diet supplemented with different levels of $\alpha$-tocopherol did not affect (p>0.05) egg weight, feed intake, body weight change or liver and abdominal fat weights. Egg production, egg mass and feed efficiency significantly (p<0.05) improved as dietary $\alpha$-tocopherol levels increased. The activities of hepatic lipogenic-related enzymes including acetyl-CoA carboxylase (EC 6. 2. 1. 3; ACC), glucose-6-phosphate dehydrogenase (EC 1. 1. 1. 49; G-6-PDH), ATP-citrate cleavage enzyme (EC 4. 1. 3. 8; CCE), NADP-malate dehydrogenase (EC 1.1.1.40; NADP-MDH) and fatty acid synthetase (FAS) were higher (p<0.05) in birds fed with the tallow diet than in those fed with fish oil diets and increased with increasing dietary $\alpha$-tocopherol levels. None of the dietary treatments significantly affected the contents of triglyceride and total cholesterol in the liver, or total cholesterol, phospholipid and total lipid in the plasma. However, the contents of phospholipid and total lipid in the liver, and triglyceride in the plasma increased as dietary $\alpha$-tocopherol levels increased. Increasing dietary $\alpha$-tocopherol levels decreased the non-esterified fatty acid (NEFA) content in the plasma and trended to decrease the cholesterol contents in the egg yolk. The lipid metabolism of laying Tsaiya ducks was influenced not only by the dietary fat but also by the supplementation levels of $\alpha$-tocopherol.

• Applied Biological Chemistry
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• 제22권3호
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• pp.173-180
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• 1979

쥐를 48시간 굶긴 뒤에 위에 탄수화물 농도가 높은 먹이를 주거나 streptozotocin을 이용하여 당뇨병을 가지게 만든 쥐에 인슈린 주사를 주었을 때 쥐 간계포의 핵단백질중 가장 주요한 0.14M NaCl에 녹는 핵단백질, histones 그리고 페놀에 녹는 핵단백질의 분포 변화를 조사하고자 SDS gel 전기영동법을 이용하였다. 각 핵단백질 분획을 전기영동법으로 분리시킨 단백질의 상대량을 비교하였을 때 0.14M NaCl 추출물은 현저한 변화를 나타내었으나 histones과 페놀로 추출된 핵단백질 분획들은 분리된 단백질 상대량에 큰 변화가 없었다. 48시간 굶긴 쥐와 정상적으로 먹이를 준 쥐의 0.14M MaCl 추출 핵단백질 분획을 비교하였을때 분자량이 50,000 과 180,000 daltons 사이에 있는 적어도 5개의 핵단백질의 농도가 다른 핵단백질에 비교하여 크게 감소되었다. 반면 분자량이 36,000 daltons 단백질의 농도는 48시간 굶긴 쥐에게 다시 탄수화물 농도가 높은 먹이를 주었을 때 24시간 동안에 정상적으로 먹이를 준 쥐에서 관찰한 핵단백질 분포 양상과 비슷한 결과를 얻었다. 당뇨병을 가진 쥐에게 인슈린 주사를 준 쥐와 인슈린주사를 주지 않은 당뇨병 쥐의 0.14M NaCl추출 핵단백질 분획을 비교 조사한 결과는 굶은 쥐에게 탄수화물 농도가 높은 먹이를 준 다음에 얻은 뒤의 결과와 정상적으로 유사하였다. 여기서 얻은 실험결과들은 0.14M NaCl 추출 핵단백질 중에 있는 어떤 핵단백질의 분포 변화가 이미 알려진 인슈린 신호에 따라 조정되고 cytosol에 있는 지방합성에 관하는 효소(lipogenic enzymes)들의 유도에 관련된 세포핵 활성 조절에 영향을 끼치고 있음을 시사해 준다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권10호
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• pp.1524-1528
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• 2003

The present study was conducted to evaluate the influence of dietary fiber on the activities of malic enzyme and citrate lyase involved in fatty acid metabolism in the colon epithelium of pigs. Thirty-six weaned 5 weeks old crossbred (Yorkshire${\times}$Swedish Landrace) piglets originating from twelve litters were randomly assigned to either a low fiber diet containing 10% non-starch polysaccharides (NSP), a control diet containing 14.7% NSP or a high fiber diet containing 20% NSP. The activity of malic enzyme in the colonic epithelium of pigs significantly (p<0.05) increased with age during the suckling-weaning transition. There was a tendency (p<0.10) of decreased malic enzyme activity in the colonic epithelium of pigs fed on the high fiber diet. At week 6, a lowered (p<0.01) activity of malic enzyme in pigs fed on the low fiber diet compared with that in pigs fed on the high fiber and the control diets. Nevertheless, there were no significant differences in the activity of citrate lyase observed either between pigs with different ages or between pigs fed with various diets. The current data suggest that piglets during the suckling-weaning transition have a limited capacity to synthesize fatty acids from carbohydrate derivatives in the coloncytes. In addition, lipogenesis in coloncytes was enhanced with age during the suckling-weaning transition. A tendency (p<0.10) to an increased capacity to utilize acetyl-CoA in coloncytes of pigs has been observed for the high fiber diet. Moreover, the present work indicated that dietary fiber resulted in a lowered rate of lipogenesis and a reduced activity of malic enzyme.

• BMB Reports
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• 제40권4호
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• pp.525-531
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• 2007

As a $\beta_2$-adrenergic agonist, clenbuterol decreases body fat, but the molecular mechanism underlying this process is unclear. In the present study, we treated 293T and L-02 cells with clenbuterol and found that clenbuterol downregulates SREBP-1c expression and upregulates CREB1 expression. Considering SREBP-1c has the function of regulating the transcription of several lipogenic enzymes, we considered that the downregulation of SREBP-1c is responsible for body fat reduction by clenbuterol. Many previous studies have found that clenbuterol markedly increases intracellular cAMP levels, therefore, we also investigated whether CREB1 is involved in this process. The data from our experiments indicate that CREB1 overexpression inhibits SREBP-1c transcription, and that this action is antagonized by CREB2, a competitive inhibitor of CREB1. Furthermore, since PPARs are able to repress SREBP-1c transcription, we investigated whether clenbuterol and CREB1 function via a pathway involving PPAR activation. However, our results showed that clenbuterol or CREB1 overexpression suppressed PPARs transcription in 293T and L-02 cells, which suggested that they impair SREBP-1c expression in other ways.

• Preventive Nutrition and Food Science
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• 제17권3호
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• pp.223-227
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• 2012

This study examined the effects of corn gluten (CG), wheat gluten (WG), and soybean protein isolate (SPI), as well as their hydrolysates, on weight reduction in rats fed a high-fat diet. Eight-month-old male Sprague-Dawley rats (n=70) were fed a high-fat diet (40% of the calories were fat) for 4 weeks. Rats were then randomly divided into seven groups and were fed isocaloric diets with different protein sources for 8 weeks. The protein sources were casein (control group), intact CG (CG group), CG hydrolysate (CGH group), intact WG (WG group), WG hydrolysate (WGH group), intact SPI (SPI group), and SPI hydrolysate (SPIH group). Body weight gain, adipose tissue weights, lipid profiles in plasma and liver; and hepatic activities of carnitine palmitoyl transferase, fatty acid synthase (FAS), malic enzyme, and glucose-6-phosphate dehydrogenase were assessed. The CGH group showed significant weight reduction compared with the other groups. Epididymal fat pad and plasma triglycerides in the CGH group were the lowest and were significantly different than those in the control group. FAS activity in the CGH group was significantly lower than that in the other groups. In conclusion, the CGH diet of these experimental animals demonstrated a weight-reducing effect by lowering the adipose tissue weight and by affecting the activities of hepatic lipogenic enzymes.

• Asian-Australasian Journal of Animal Sciences
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• 제15권7호
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• pp.1026-1030
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• 2002

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.

• Journal of Nutrition and Health
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• 제28권4호
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• pp.268-281
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• 1995

This study was undertaken to elucidate the effect of DHA-rich fish oil (DHA-rich oil) added to different dietary fats on lipid metabolism. Rats were fed perilla oil, sesame oil and beef tallow with or without DHA-rich oil for 12 weeks. The weight gain was higher in groups with DHA-rich oil than that of groups without DHA-rich oil, with DHA-rich oil, while weight of epididymal fat pad was lower in perilla oil and beef tallow groups with DHA-rich oil. The contents of total lipid and triglyceride in plasma were not affected by dietary fat types, but that of total and HDL cholesterol in plasma were higher in sesame oil group than perilla oil and beef tallow groups without DHA-rich oil. The contents of total lipid, triglyceride, total cholesterol, HDL cholestrol and LDL cholesterol in plasma were decreased by DHL-rich oil addition. The contents of total lipid, total cholesterol and triglyceride in the liver were not affected by dietary fat type. The contents of total cholesterol and triglyceride in the liver were not affected by dietary fat type. The contents of total lipid and TG in liver were not affected by DHA-rich oil addition while hepatic cholesterol increased by DHA-rich oil addition. The activities of glucose 6-phosphate dehydrogenase and malic enzyme were highest in beef tallow group without DHA-rich oil and decreased by DHA-rich oil addition. Peroxisomal ${\beta}$-oxidation had an inverse relationship against the activities of lipogenic enzymes. In conclusion, dietary DHA-rich oil decreased fat accumulation and had hypolipidemic effect, especially in beef tallow group. Also groups with DHA-rich oil showed more hypolipidemic effect than perilla oil group. And DHA-rich oil addition to diets resulted in increasing dietary n-3/n-6 ratio. Therefore increase in n-3/n-6 ratio as well as dietary DHA were considered to be responsible for the hypolipidemic effect resulted from DHA-rich oil addition.