• Asian-Australasian Journal of Animal Sciences
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• 제24권9호
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• pp.1274-1281
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• 2011

Dietary protein restriction affects lipid metabolism in rats. This study was performed to determine the effect of a low protein diet on hepatic lipid metabolism and insulin sensitivity in growing male rats. Growing rats were fed either a control 20% protein diet or an 8% low protein diet. Feeding a low protein diet for four weeks from 8 weeks of age induced a fatty liver. Expression of acetyl-CoA carboxylase, a key lipogenic enzyme, was increased in rats fed a low protein diet. Feeding a low protein diet decreased very low density lipoprotein (VLDL) secretion without statistical significance. Feeding a low protein diet down-regulated protein expression of microsomal triglyceride transfer protein, an important enzyme of VLDL secretion. Feeding a low protein diet increased serum adiponectin levels. We performed glucose tolerance test (GTT) and insulin tolerance test (ITT). Both GTT and ITT were increased in protein-restricted growing rats. Our results demonstrate that dietary protein restriction increases insulin sensitivity and that this could be due to low-protein diet-mediated metabolic adaptation. In addition, increased adiponectin levels may influences insulin sensitivity. In conclusion, dietary protein restriction induces a fatty liver. Both increased lipogenesis and decreased VLDL secretion has contributed to this metabolic changes. In addition, insulin resistance was not associated with fatty liver induced by protein restriction.

• Nutritional Sciences
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• 제1권1호
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• pp.3-7
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• 1998

The aim of the present investigation was to see whether an anabolic steroid, nandrolone phenylpropionate (NPP), exerts protienanabolic effects under such adverse nutritional conditions as protein deficiency and protein-energy malnutrition in male rats. feeding on a low-protein (8% casein) diet resulted in a marked reduction in body weight gain that was associated with reductions in body protein and protein content of gastrocnemius muscle. Administration of NPP (4 mg/kg body weight) did not alter muscle and body protein depletion induced by a low-protein diet. 50% food restriction caused reductions in body protein and in protein content of gastrocnemius muscle. These reductions were partially prevented by NPP (4 mg/kg body weight). Food restriction did not affect plasma concentration of corticosterone, insulin, or tetosterone plus dihydrotestosterone. On the other hand, neither plasma concentration of corticosterone nor insulin were affected by NPP. The present results show that anabolic steroids do not express anabolic effects under conditions of protein deficiency, but in protein-energy malnutrition, anabolic steroids exert their anabolic effects even in male rats.

• 동아시아식생활학회지
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• 제11권5호
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• pp.368-378
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• 2001

This study was performed to investigate the effects of isolated soyprotein and salt (NaCl) restriction on the serum lipid and the kidney functions of streptozotocin-induced diabetic rats. Sprague-Dawley males of normal and streptozotocin-induced diabetic rats were raised for 6 weeds divided into 4 groups each according to protein sources and salt levels. The sources of protein were isolated soyprotein and casein. Salt levels tested were 0.1% (normal) and 0.01% (low). The results are summarized as fellows: kidney weight, blood glucose, hemoglobinAlc, GFR and urinary protein of diabetic groups were higher than those of normal groups. Isolated soyprotein lowered total lipids, triglycerides, and total cholesterol in serum and plasma angiotensin II concentration as well as alleviated kidney enlargement and GFR in diabetic rats. Salt restriction didn\\`t affect serum lipid level but decreased GFR and increased angiotensin If concentration. In conclusion, isolated soyprotein decreased serum lipids, plasma angiotensin II concentration, sidney enlargement and GFR, while salt restriction increased plasma angiotensin II concentration. The results suggest that isolated soyprotein and salt restriction seem to cause different effects on plasma angiotensin II concentration and that isolated soyprotein might be of value in the prevention of diabetic artherosclerosis and diabetic hypertension.

• Journal of Nutrition and Health
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• 제15권1호
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• pp.62-69
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• 1982

Sprague Dawley 종의 어미 쥐에게 수유기에 양적인 식이제한을 한 후, 이유이후 새끼쥐에 게 4주일간 식이회복을 시켰다. 각 새끼 쥐에 있어서, 임의로 먹인 대조군에 비하여 식이제한군의 체중, 근육 단백질, 근육 3-methylhistidine과 혈청 단백질 함량의 변화에 대하여 분석하였다. 식이 제한군의 체중은 대조군보다 매우 낮았으며 , 식이 회복에 의하여 거의 정상으로 회복 되었다. 또한 식이 제한군의 근육 단백질, 3-methylhistidine 함량과 혈청 단백질 함량도 어미 쥐의 식이제한에 의하여 대조군에 비하여 매우 낮았으나, 4주일간의 식이회복에 의하여 빨리 증가하여, 대조군과의 유의차가 없었다. 이로써 영양불량의 쥐에서는 3-methylhistidine의 대사가 장애를 받아 저하되나, 이유 이후의 식이회복에 의해 거의 정상으로 회복됨을 알 수 있다.

• Journal of Nutrition and Health
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• 제16권4호
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• pp.263-272
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• 1983

Effects of dietary protein qualify, energy restriction, and subsequent rehabilitation were studied in the weanling rats. Rats were devided into the six experimental diet groups. Rats in AC (casein- containing diet ), AS (soyprotein-containing diet), and AG(gluten-containing diet) group consumed their diets ad libitum, and rats in PC, PS, PG groups were pair-fed in 60% of the of amounts eaten by corresponding rats in the AC, AS, AG groups, respectively. After 3 weeks of nutritional restriction, all rats were switched to the AC diet for 14 days. At the end of restriction period, body weight, weight gain, food intake, and FER were higher in casein- fed rats than other groups of rats. The differences were, however, disappeared with rehabilitation diet, except body weights which were not fully recovered until the end of experiment. The weights of liver, gastrocnemius muscle, kidney, small intestine, spleen, and lung were the highest in the casein group, and the lowest in gluten group at the end of restriction period. The recovery with rehabilitation diet were differ in different organs. The muscle and liver seemed to be the most affected organs by dietary protein quality and energy restriction. There were no differences in brain weights among the experimental groups during the restriction period, however, after 2 weeks of rehabilitation, rats in AC group showed lower brain weight compared to AC and AS groups, and the brain weight of PC group was lower than AC group. Protein contents in liver and muscle showed the same trends as their weights. Gluten-fed rats showed low serum protein concentration, but recovered fully with rehabilitation diet for 3 days.

• 운동영양학회지
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• 제13권1호
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• pp.1-7
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• 2009

It has been shown that both caloric restriction and exercise, enhances glucose uptake through translocation of GLUT-4 protein. It remains unclear how exercise and caloric restriction affect the changes in VAMP (vesicle-associated membrane protein) in skeletal muscle and GLUT-2 in liver. This study investigated the effects of exercise training and caloric restriction on the expressions of glucose transport relating proteins in muscle and liver tissues in diabetic rats. Forty male Sprague-Dawley rats (250±10 g; 8 week in age) were assigned equally to four different groups; control (C), exercise only (E), dietary restriction only (D) and dietary restriction and exercise (DE). Daily food consumption was monitored to establish baseline intake. Both C and E groups consumed baseline food intake while D and DE groups were provided with only 60% of baseline total food intake. Forty-eight hours after intraperitoneal injection of STZ (50 mg/kg), diabetes was confirmed (8-hr fasting blood glucose levels ≥300 mg/dl). Rats in the E and DE groups exercised on a motorized treadmill for 30 min/d, 5 days/week for 4 weeks (5 min running at 3 m/min, 0% grade; 8 m/min for the next 5min, and then 15 m/min for 20 min). Rats were sacrificed 48 hrs after the last bout of exercise. Soleus muscle and liver were extracted to analyze for GLUT-4, VAMP-2, and GLUT-2, respectively. All variables were analyzed using the Western Blotting technique. All values were expressed as optical volume measured by optical density. A Two-way ANOVA was used to examine the difference between groups and applied Duncan's test for post-hoc. No significant differences in GLUT-2 expression were found among groups. However, E (280133±13228 arbitrary units{AU}) and DE (268833±14424 AU) groups showed significantly higher (p<.001) levels of GLUT-4 as compared with C (34461±2099 AU) and D groups (27847±703 AU). VAMP-2 protein expression increased (p<.001) in E (184137±7803 AU) and DE (189800±10856 AU) groups as compared to C (74201±8296AU) and D (72967±863 AU) groups. These results suggest that either exercise with or without caloric restriction increases the up-regulation of GLUT-4 and VAMP-2 in skeletal muscle of diabetic rats. However, GLUT-2 protein in liver was not affected by either exercise or exercise with caloric restriction.

• Journal of Nutrition and Health
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• 제24권3호
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• pp.149-156
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• 1991

고지방식이와 총열량섭취 제한식이가 protein kinase C 활성에 미치는 영향을 규명하고자 기타 양양소 또 총열량섭취가 정확이 조절된 식이를 제조하여 투여해본 결과, protein kinase C의 활성은 본 실험에서 사용한 옥수수유의 양의 증가에 따라 cytosolic과 membrane-associated protein kinase C의 활성을 모두 증가시키는 것을 관찰 하였다. 또한 기타 영양소는 같게 투여하고 열량소만 40% 감소시킨 실험군은 대조군에 비해 양쪽의 protein kinase C가 모두 감소하는 경향을 보였다.

• 한국식품과학회지
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• 제8권4호
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• pp.263-272
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• 1976

According to the intercombined review of chemical and biological investigation it has been noted that the metabolizable energy per gram dietary protein of mixed diet of daily intake patterned by Korean population has been found 3.4-3.6 Cal., which entails 10-12% level of the protein calorie percentage of total metabolizable energy, the biological value being fallen within the scope 63-73. The structure of dietary protein has revealed that the lysine and isoleucine were primary limiting amino acids and threonine secondary limiting as a general trend, however, it is assumed that the ultimate nutritional effect of dietary protein might be restricted uniformly among regions by the amount of lysine, since the lysine availability has been yielded as low as 72-82% level. As for the net protein utillization NPUst falls in the range of 52-62 and the NPUop 47-58. In either part the mountainous region has demonstrated lowest value and the urban area highest, these trend being obviously associated with the ratio of animal protein relative to the vegetable origin. The net dietary protein calorie percentage (NDpCal %) has been found within the range of 5-7 that may be capable of meeting the requirement for the maintenance of adult, though for the growth it is insufficient. Present level of total caloric intake would not influence on the fate of protein value of prevailing regional diet in terms of caloric restriction, since the present intake of food energy is higher than the lower limit of caloric intake that would impair the biological performance of dietary protein fed ad libitum basis. Based on the protein efficiency, the adequacy of current level of protein intake was analyzed in terms of utilizable protein, and it has been demonstrated that the 37.8g of utilizable protein in the fishery region and 38.2g in the mountainous region were bellow the FAO recommendation. Accordin to the hematological study it may be interpreted that the anemic symptoms of the mountainous region has some possibility of being related to the inferior status of dietary protein in quality as well as in quantity.

• Journal of Nutrition and Health
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• 제3권3호
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• pp.167-178
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• 1970

체중이 $43{\pm}2g$ 되는 흰쥐 암수 70마리를 7 group으로 나누어 Sugar-casein diet를 사료로 하여 pair-feeding에 의한 50% 식이제한으로 9주간 사육한 실험결과는 다음과 같다. 50%식이제한으로 나타나는 현상은 체중감소와 더불어 각 장기의 무게가 감소하였고 실험기간이 길어질수록 감소율이 높았다. 각 장기중 간과 비장의 무게의 감소가 심했고 뇌가 가장 영향을 적게 받았다. 질소의 체내 보유율은 식이제한 group이 control group 보다 높았으나 몸무게 g당 체내 보유율은 식이제한 group이 높았고 식이제한 group의 몸무게는 감소하여 신체 내에서 단백질의 경제적연 이용을 알 수 있다. 식이제한으로 인한 각장기의 질소 RNA, DNA함량은 비장이 식이제한에 가장 예민하고 뇌가 가장 둔한 경향을 나타내었다. 식이제한으로 Hematology에 뚜렷한 변화는 없고 식이제한으로 anemia의 현상이 나타난다고는 할 수 없고 Serum albumin 이나 A/G Ratio도 두 group 사이에 식이제한 전기간을 통해 차이가 없었다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1187-1193
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• 2015

This study determined the effects of dietary restriction on growth and the expression of lipid metabolism and growth hormone signaling genes in the longissimus dorsi muscle (LM) of Korean cattle. Thirty-one Korean cattle steers (average age 10.5 months) were allocated to normal (N; n = 16) or dietary restriction (DR; n = 15) groups. The feeding trial consisted of two stages: for the 8-month growing period, the DR group was fed 80% of the food intake of the normal diet, and for the 6-month growth-finishing period, the DR group was fed a DR total mixed ration with 78.4% of the crude protein and 64% of the net energy for gain of the normal diet. The LM was biopsied 5 months (period 1 [P1] at 15.5 months of age) and 14 months (period 2 [P2] at 24.5 months of age) after the start of feeding. The mRNA levels were determined using real-time polymerase chain reaction. Body weight, daily feed intake, average daily gain, and feed efficiency were lower in the DR group compared with the normal group at both P1 and P2. At P1, the lipogenic fatty acid synthase (FASN) mRNA levels were lower (p<0.05) in the DR group compared with the normal group. The DR group tended (p = 0.06) to have higher of levels of growth hormone receptor (GHR) mRNA than the normal group. At P2, the DR group tended to have lower (p = 0.06) androgen receptor (AR) mRNA levels than the normal group. In conclusion, our results demonstrate that dietary restriction partially decreases the transcription of lipogenic FASN and growth hormone signaling AR genes, but increases transcription of the GHR gene. These changes in gene transcription might affect body fat accumulation and the growth of the animals.