• Journal of Nutrition and Health
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• v.34 no.8
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• pp.865-871
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• 2001

The adipose tissue hormone leptin has been proposed to be involved in the regulation of flood intake and energy expenditure via thermogenesis by uncoupling protein(UCP) in brown adipose tissue(BAT). The objective of the study was to examine the effects of high fat diet on the serum leptin levels, BAT UCPl expression and the body fat mass in rats after weaning. During experimental period of 12 weeks, 4 male Sprague-Dawley rats were killed for the baseline experiment at 4 weeks of age while the remaining rats were fed the two different diets: the control diet AIN-76A(n = 20), high fat(beef tallow) diet(n = 20) ad libitum, which provided 11.7% or 40% of calories as fat, respectively. At 16 weeks of age, the increase in the food efficiency ratio(FER) was related to fat mass in rats on high fat diet. Serum leptin level was increased by age and dietary high fat. There was no difference in serum insulin level between groups until 10 weeks of age, but rats fed high fat diet for 12 weeks showed hyperinsulinemia. The amount of body fat pads was increased significantly in high fat group compared to normal diet group. Visceral fat mass affected acutely by high fat diet, as a result, it was higher in rats fed high fat diet for 2 weeks than normal diet. At 16 weeks of age, BAT and visceral fat mass were significantly high in high fat group. Also, the serum leptin levels reflected the amount of body fat mass. BAT UCPI mRNA expression increased with age and dietary high fat. This study demonstrates that dietary high fat increased serum leptin levels, BAT UCPI expression and body fat mass. Futhermore, in rats fed high fat diets, the increases in leptin and UCPI expression counteracts only in part the excess adiposity and obesity.

• Journal of Nutrition and Health
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• v.27 no.10
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• pp.967-978
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• 1994

This study was done to investigate the effect of age and dietary linolenic acid content and the linolenic acid/linoleic acid(LNA/LA) ratio on the lipid metabolism and formation of PGI2 and TXA2. The male Sprague-Dawley rats were fed 6 different with 0.2, 0.4, 0.6 of LNA/LA ratio within either 8% LNA(high LNA) or 4% LNA(low LNA) of fatty acid content for different feeding period(1, 4, 12 month). The dietary fat used were sesame oil, perilla oil, soybean oil and beef tallow. The concentration of serum total lipid, total cholesterol and HDL-C were increased with aging. Triglyceride concentration was decreased in 0.2 ratio of LNA/LA. The lipid content of liver showed similar tendency to that of serum. The ratio of PGI2/TXA2 was increased in 1 month rats and antithrombotic effect was reduced significantly with increasing age. The PGI2/TXA2 ratio was tended to be higher in diet of 0.2 and 0.4 LNA/LA ratio at high LNA level and in diet of 0.6 LNA/LA ratio at low LNA level. Especially PGI2/TXA2 ratio was increased linearly with rising LNA/LA ratio at low LNA level. It seemed that the LNA content and LNA/LA ratio had interaction to increase the antithrombotic effect bychanging TXA2 synthesis. And the dietary fatty acid related effect lowering the serum and liver lipid content, excepting triglyceride, was increased when dietary n3/n6 ratio was high(0.6) at both high and low n3 level. Therefore, it could not be recommended to consume large amount of n3 fatty acid or high ratio of n3/n6 to prevent cardiovascular diseases. These results suggested that the dietary fatty acid ratio of n3/n6 could be determined based on the n-3 content of dietary fat to reduce the risk of cardiovascular disease.

• Journal of Nutrition and Health
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• v.30 no.2
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• pp.187-194
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• 1997

The effects of diet induced hyperlipidemia on kidney function were studied in Sprague-Dawley rats fed high fat diet containing 20% beef tallow and high cholesterol diet containing 5% cholesterol for 8, 12, 16 weeks, respectively. The concentrations of serum total lipid, total cholesterol and LDL-cholesterol were significantly high cholesterol diet groups during all experimental periods (p<0.05). HDL-cholesterol concentration was the lowest value in high cholesterol diet group of 16 weeks(p<0.05). Triglyceride concentration was not affected by experimental diets. Serum total protein, albumin and creatinine concentration tended to higher in high cholesterol diet groups than those in high fat diet groups. And serum urea-N concentration was higher in high fat diet group of 16 weeks than that in other diet groups. Urinary total protein and urea-N were higher in high cholesterol diet groups than those in other diet groups regardless of experimental period period. There was no significant difference in urinary creatinine concentratin among diet groups(p<0.05). GFR was lower in high cholesterol diet groups than that in high fat diet groups at 8, 16 weeks, respectively. Wet weight per body weight, total lipid, triglyceride, total cholesterol concentations of liver tissue were apparently high in high cholesterol diet groups(p<0.05). Kidney wet weight per body weight wer not affected by experimently diets, total lipid concentration of kidney tissue was significantly high in high fat diet groups of 12 weeks(p<0.05), kidney tissue triglyceride concentrations of high cholesterol diet groups of 12, 16 weeks apparently low, and total cholesterol concentration of kidney tissue was higher in experimental diet groups than that of control groups at 12, 16 weeks(p<0.05). Fecal excretion, total lipid, triglyceride and cholesterol concentrations of feces were markedly high in all high cholesterol diet groups except high fat diet group of 16 weeks. The results of light microscopic examination indicated that glomerulosclerosis was not obsrved in rats fed experimental diets.

• Journal of Nutrition and Health
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• v.28 no.11
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• pp.1078-1090
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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 thrombosis and lipid peroxidation. Rats were fed perilla oil, sesame oil and beef tallow with or without DHA rich oil for 12 weeks. Bleeding time was the longest in Perilla oil groups with or without DHA rich oil. The productions of thromboxane B2(TX B2) and 6-keto Prostaglandin F1$\alpha$(6-keto PG F1$\alpha$) were the highest in Esame oil group without DHA rich oil. Bleeding time tended to be extened and group showed the most antithrombotic effect among three oil groups when DHA rich oil added. The antithrombotic effect by DHA rich oil addition seemed to be resulted from the increase of dietary n-3 fatty acid rather than DHA. And there was not the difference in antithrombotic effect between DHA and $\alpha$-linolinic acid. The level of TBARS(thiobarbituric acid reactive substances) in plasma and liver, and the activities of lipid peroxide metabolizing enzymes(catalase, superoxide dismutase and gluthathion peroxidase) in erythrocyte and liver were not affected by the dietry fat type and DHA rich oil addition, except that activity of hepatic catalase was increased by DHA rich oil addition. Therefore it revealed the DHA level added in this study seldom affected lipid peroxidation. However, it dose not conclude that DHA level of this study make low production of lipid peroxide because the peroid of our study was short.

• Journal of Nutrition and Health
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• v.30 no.10
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• pp.1140-1152
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• 1997

Serum and liver lipid levels and fatty acid composition of liver phospolipids (PL) were investigated in 36 rats which consumed either one of five different dietary fats or a high carbohydrate diet for 4 weeks. As the sources of five dietary fats, concentrated cicosapentaenoic acid(EPA), fish oil (FO), perilla oil(PO), corn oil(CO) and beef tallow (BT) were provided to the rats. As a control group, cron starch (CS) replaced dietary fat. The FO group showed lower serum total cholesterol (TC), high density lipiprotein cholesterol(HDL-C) and serum PL levels than those of the CO group(p<0.05). There were no significant differences in serum TC and serum HDL-C levels between the polyunsatured fatty acid(PUFA) groups and the EPA, FO and PO groups. The CS group showed the highest level serum TC. Compared with the CS group, both the EPA and CO groups showed significantly lower atherogenic indices(AI). However, there were no significant differences in AI among different dietary fat groups. No significant differences in liver triglyceride (TG) , TC and PL levels were detected among the six experimental groups. Phosphatidylcholine(PC) and phosphatidylethanolamine(PE) composed 30-40% and 15-20% of total liver PL, respectively. The fatty acid composition of liver PC and PE reflected dietary fatty acid composition . Compared to the different dietary fat based diets used in our study, the high carbohydrate diet had the most adverse effects on serum lipid profiles. However, we can not conclude from this result that long chain n-3 PUFA diets such as the EPA and FO based diets have more beneficial effects on serum lipid profiles than n-6 PUFA diet such as the CO based diet or shorter chain n-3 PUFA diets like the PO based diet.

• Journal of Nutrition and Health
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• v.25 no.1
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• pp.3-11
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• 1992

This paper examines the effects of dietary fats on the fatty acid composition and market enzyme activites during liver damage in 2-acetylaminofluorene treated rats. Weaning Sprague-Dawley male rats were fed the diet of beef tallow(BT source of sturated fatty acid) corn oil(CO source of n-6 fatty acid) and perilla oil(PO source of n-3 fatty acid) at the level of 15% fat. Ten days after feeding 2-acetylaminofluorene(2-AAF) was injected intraperitoneally twice every week at the level of 50mg/kg body weight for 7 weeks. Liver microsomal and cytosolic fractions were collected to determine the microsomal fatty acid composition lipid peroxide(malondialdehyde MDA) contents glucose 6-phosphatase(G6 Pase) activity cytochrome(Cyt) P-450 contents and cytosolic glutathione S-transferase(G6 Pase) activity cytochrome(Cyt) P-450 contents and cytosolic glutathione S-transferase(GST) activity. The fatty acid composition in microsomal fraction was reflected by different dietary fats. By 2-AAF treatment linoleic acids were increased regardless of the diet MDA contents were higher in CO group than it was in BT group. However 2-AAF treatment decreased MDA contents in all dietary groups. G6Pase activity of BT group was higher than those of the other gropus. CO group had the highest Cyt P-450 contents and 2-AAF treatment lowered Cyt P-450 contents only in CO gropu GST activites were higher in CO than in BT group whereas the enzyme activites were increased by 20AAF treatment in all dietary groups. These results suggest that dietary fats and 2-AAF treatment in all dietary groups,. These results suggest that dietary fats and 2-AAF treatment affect microsomal fatty acid composition The enzyme activities concerned with liver damage were influenced differently by dietary fats and 2-AFF treatment Although PO diet contains much more polyunsaturated fatty acids than CO diet PO diet doesn't cause more oxidant stress compared with CO diet in these data.

• Journal of Nutrition and Health
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• v.15 no.1
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• pp.47-53
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• 1982

The study was designed to observe the effects of dietary intake of three different levels of polyunsaturated to saturated fatty acid (P/S) ratio on plasma HDL - cholesterol and triglyceride in plasma and tissues of adult rats. Rats were assigned into the three diet groups, composed of protein 24%, carbohydrate 46%, and fat 30% of total caloric intake. However, the P/S ratio of fat was adjusted by using beef tallow, corn oil and perilla oil to give 0.2, 1.1 and 6.0. All groups were fed ad libitum for 4 week. Plasma cholesterol level was decreased but net significantly with increasing P/S ratio of dietary fat, and showed significant negative correlation coefficient. Plasma TG level was also decreased with increasing PUFA level of dietary fat. However, the effect of P/S ratio (6.0) was not greater than that of P/S ratio (1.1) on plasma TG concentration. This implied that high level of PUFA was not required to change plasma TG level as much in the case of HDL-cholesterol. Plasma HDL-cholesterol was significantly increased only in the group of P/S ratio 6.0 which suggested that high level of dietary PUFA was required to increase HDL level. There was a decreasing trend in the levels of total cholesterol and TG per g liver with increasing P/S ratio of dietary fat. There was no effect in the levels of TG per g skeletal muscle by P/S ratio but the level of cholesterol per unit skeletal muscle was rather increased with increased P/S ratio.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.255-263
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• 2012

Polybrominated diphenyl ethers (PBDEs) are a group of brominated flame retardants (BFRs), which are used in a variety of consumer products. Several of those are produced in large quantities. Their chemical structure similarities to polychlorinated dibenzo-p-dioxins and polychlorinated biphenyls (PCBs), as well as their toxicity, has been studied. PBDEs are persistent and lipophilic, which results in their bioaccumulation in the fatty tissues of organisms and enrichment throughout food chains. In addition, a number of studies also reported high levels of PBDEs in animals and food resulting from the use of contaminated animal feed Public concern about PBDEs levels in animals and food has been raised. Feed contamination by toxic chemicals has been the cause of the contamination of poultry products. The purpose of this study was to evaluate PBDEs in pig feed to search the origin chase of POPs in pigs. Feed samples were obtained wheat from East Europe, corn from South America and America, soybean meal from Korea, America, South America and India and tallow from Korea. The preparation of samples was based on the EPA method 1614. Instrumental analysis was based on the use of high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC/HRMS). Quantification was carried out by the isotopic dilution method. The analysis of ${\Sigma}PBDEs$ involved 22 PBDE congeners, including BDE-17, 28, 47, 49, 66, 71, 77, 85, 99, 100, 119, 126, 138, 153, 154, 156, 183, 184, 190, 191, 196 and 197.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.2
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• pp.281-290
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• 1993

This experiment was designed to evaluate the effect of degree of unsaturation (Experiment 1) and the chain length of constituent fatty acids of dietary fats (Experiment 2) on-3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activities in the liver and small intestine of chicks. Chicks were fed experimental diets for 10 days and then killed for the determination of the HMG-CoA reductase activities in the intestinal epithelial cell and hepatic microsomes. The hepatic HMG-CoA reductase activity showed the highest value in chicks fed the tallow-containing diet. Chicks fed diets containing safflower or coconut oil resulted in a significantly lower intestinal HMG-CoA reductase activity in comparison with those fed the olive oil-containing diet. The hepatic HMG-CoA reductase activity was significantly higher when fat-free and trilaurin were fed than when any other triglycerides were fed. This activity showed the lowest value in the chicks fed the diet containing tristearin. The HMG-CoA reductase activities in the jejunum and ileum were significantly or tended to be higher when trilaurin was fed than when any other triglycerides were fed. Except when trilaurin was fed, the presence of saturated fat in the diet did not have a significant effect on the intestinal HMG-CoA reductase activity, unlike the effect shown when a highly unsaturated fat was added to the diet. There was no significant correlation between the HMG-CoA reductase activities of the liver and intestinal, and the HMG-CoA reductase activity and cholesterol content of the intestinal epithelial cells.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1865-1873
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• 2007

An experiment was performed to evaluate the effects of dietary metabolizable energy (ME) and lysine on carcass characteristics and meat quality in Arbor Acres (AA) broilers from 1 to 56 days of age. A total of 2,970 1-d-old male broiler chicks were randomly allocated to nine dietary treatments (three ME levels in combination with three lysine levels), and dietary ME and lysine concentrations were formulated by varying corn, soybean meal, tallow, and L-lysine sulfate concentrations. Live body weight (BW), carcass weight (CW), dressing percent, breast muscle weight (BMW), yield of breast muscle, muscle color (CIE L*, a*, and b*), pH values 45 min and 24 h postmortem ($pH_{45}$, and $pH_{24}$), meat shear force value (SFV), and water loss rate (WLR) were evaluated. Results showed that live body weight and dressing percent increased (p<0.05) as dietary energy increased. Higher dietary lysine content improved breast muscle weight. Neither carcass weight nor yield of breast muscle was affected by dietary energy or lysine content. Higher ME increased the b* value (p = 0.067) and $pH_{24}$ value (p<0.05), whereas it decreased SFV (p<0.05) and WLR (p = 0.06). Only water loss rate was influenced (p<0.01) by dietary lysine, which was higher in broilers from the high lysine diet as compared to those from medium or low lysine diets. The $pH_{45}$ value and L* value of breast muscle were not affected by ME or lysine. Significant interaction of dietary ME and lysine was found on a* value of breast muscle. These results indicated that dietary ME and lysine had important effects on breast muscle growth and meat quality, however their effects were different. Different concentrations of dietary ME and lysine might be considered to improve meat quality.