• Journal of Nutrition and Health
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• v.36 no.5
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• pp.452-458
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• 2003

Soybean is a rich source of isoflavones such as genistein and daidzein. Soy isoflavones have both weak estrogenic and anti-estrogenic effects and are structurally similar to tamoxifen, an agent that has an effect similar to that of estrogen in terms of reducing postmenopausal bone loss. The purpose of this study was to determine the effects of differences in protein source (casein vs soy) and isoflavone levels (reduced vs higher levels) on selected bone markers and hormones in growing male rats. Thirty weanling Sprague-Dawley young rats were divided into 3 groups: The control group was fed a casein-based diet, the soy concentrate group was fed soy protein with totally reduced isoflavones content (isoflavones 0.07 mg/g protein), and the soy isolate group was fed soy protein with a higher than normal isoflavones content (isoflavones 3.4 mg/g protein). The degree of bone formation was estimated by measuring serum osteocalcin and alkaline phosphoatase (ALP). By determining collagen cross-linkage by immunoassay and correcting with creatinine values, the bone resorption rate was compared. Serum osteocalcin, growth hormone, estrogen and calcitonin were analyzed using radio immunoassay kits. The bone formation marker and ALP activity were differentiated by protein source, showing higher values than casein in feeding either soy isolate or soy concentrate. In this study using growing rats, the differences in isoflavone contents were not a significant factor in either bone formation or bone reaborption markers. Moreover, the soy isolate group had significantly higher levels of growth hormone than the casein group. The findings of this study suggest that growth hormone is partially responsible for its bone-formation effects in young growing rats. Soy protein and the isoflavones in soy protein are beneficial for bone-formation in growing male rats. Therefore, exposure to soy protein and isoflavones early in life may have long-term health benefits in preventing bone diseases such as osteoporosis. Further study to evaluate the mechanism of action of isoflavones on bones is warranted. (Korean J Nutrition 36(5): 452∼458, 2003)

• Nutritional Sciences
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• v.5 no.2
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• pp.53-59
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• 2002

This study was conducted to examine the effects of dietary sources of fatty acids and protein on serum protein profiles, hepatic functional enzyme activities, mammary tumor incidence and tumor weight in 7, 12-dimethylbenz($\alpha$)anthracene (DMBA)-treated rats. The sources of dietary fatty acids were 18n6 (rich in linoleic acid), 18n3 (rich in linolenic acid) and 22n3 (rich in DHA) : sources of dietary protein were casein (C) and soy protein isolate (S). mammary tumors (MTs) were chemically induced by DMBA (9 mg/100 g body weight) which was gastrically intubated at 7 weeks of age. Each experimental diet was given for the following 25 weeks. Casein-fed rats (group C) exhibited significantly higher levels of weight gain and FER (food efficiency ratio) than did group S. Group C showed higher levels of serum protein and globulin, and higher albumin/globulin (A/G) ratios than group S. Liver functional enzyme activities (GOT, GPT, ALP, LDH, $\gamma$-GT) and LDH/GOT ratios were not influenced by dietary protein. GPT activity was lower in the group given 18n3, and ALP activity was lower in the group given 18n6. The incidence and total number of MTs appeared to be lower in the group given 22n3 than in the group given 18n3 or 18n6, even though the average weight of MTs was highest in the group given 22n3, The average weight of MTs was higher in the C group than in the S group. MT incidence had a positive correlation with LDH activity and LDH/GOT ratio. The average weight of MTs had a negative correlation with serum albumin levels and A/G ratios, and a positive correlation with ALP activity. This research suggests that the measurement of serum protein profiles and liver functional enzyme activities may be utilized to monitor the development of mammary tumors.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.11
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• pp.1523-1528
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• 2000

Four Suffolk ewes were used in Latin Square switch over design to study the effects of varying levels and sources of protein on heat production and thermoregulatory responses at daytime high ($33^{\circ}C$ temperature. They were fed Italian ryegrass hay supplemented with fishmeal and/or urea, providing three different levels of crude protein (CP) (low/unsupplemented: 7.9, medium: 11.6, and high: 15.8%) at $1.5{\times}maintenance$. Feeds were distributed at 0900 (30%) and 1700 (70%). Urea diet caused higher heat production and increased vaginal temperature compared to fishmeal and fishmeal-urea mix diets. Time spent standing, skin temperature and respiration rate of sheep fed urea were similar with those of sheep fed fishmeal. Sheep fed diet with low CP level had higher heat production, increased vaginal and skin temperature than sheep fed diet with medium CP content. Sheep on high CP diet produced significantly more heat than sheep fed medium CP diets. Their vaginal temperatures were similar with those of sheep fed medium CP diet but lower than those of sheep fed low CP diet. Respiration rates of sheep and time spent by them for standing on all diets did not differ significantly. These results suggest that urea is inferior protein supplement for thermoregulation of animal at hot environment, as it induced higher heat production than fishmeal and fishmeal-urea mix. Thermoregulatory response on fishmeal-urea mix diet was similar to fishmeal diet. Increasing CP of the diet from low to medium gives advantage for thermoregulation of animal. Increasing CP further to high level was not beneficial as it resulted in the responses of sheep similar to those on low protein diet.

• Toxicological Research
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• v.20 no.3
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• pp.213-223
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• 2004

This work aimed to study the effectiveness of cellular oxidative parameter (malondial-dehyde, protein carbonyl, and 8-hydroxy-2'deoxyguanosine). The experimental groups were aluminum treated rats and control rats. Aluminum treatd rats were given intraperitoneally aluminum nitrate nonahydrate ($Al^{3+}$, 0.2 mmol/kg) daily for 30 days except Sunday. Control rats were injected 1 ml of saline. After the dose, rats were decapitated and hippocampus and cerebral cortex were removed. The measured parameters were tissue malondialdehyde (MDA, index of lipid peroxidation), protein carbonyl (index of protein oxidation), 8-hydroxy-2'-deoxy-guanosine (8-OHdG, index of DNA oxidation), reduced glutathione (GSH) levels as well as glutathione reductase (GR) and catalase. AI concentrations in the tissues were also measured. All results were corrected by tissue protein levels. The results were as followed; 1. The concentrations of AI in the cortex and hippocampus were significantly higher in the AI-treated rats than in the control rats. 2. Antioxidative enzyme's activity, catalase and GR, were significantly higher in the AI-treated rats than the control rats. GSH levels were also higher in the AI-treated rats. 3. MDA, protein carbonyl, and 8-OHdG concentration of AI-treated rats were significantly higher than those of control rats. 4. The concentrations of antioxidants, and oxidative stress parameter were correlated with the concentrations of AI in hippocampus and cerebral cortex. Catalase and GR activity were also correlated with the concentration of AI. Based on these results, it can be suggested that intraperitoneally injected AI was accumulated in the brain and induced the increase of antioxidant levels and antioxidative enzyme activity. Also, the oxidative products of cellular macromolecules are significantly related to tissue AI concentration. Therefore MDA, protein carbonyl, and 8-OHdG are useful markers for oxidative stress on cellular macromolecules.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.2
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• pp.237-248
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• 1992

The effect of 16 different dietary rations, computed by the combinations of 13, 16, 19 or 22% CP and 2600, 2800, 3000 or 3100 kcal ME/kg, on growth performances and carcass yield of Starcross layers were assessed in two similar experiments. In both experiments, the body weight, eviscerated carcass yield, edible carcass yield, length of digestive tract and shank length increased but the feed intake decreased linearly with the increase of dietary CP and ME levels. The liver and gizzard weights as percentages of live weight tended to be increased with the increase of dietary CP and ME levels. The carcass dry matter, crude protein, fat, ash and energy content were not influenced by the dietary CP and ME levels. Dietary CP levels had positive correlations with all the parameters (except feed and energy intake and carcass dry matter). However, the dietary ME levels were positively correlated with all the parameters (except feed and energy intake; carcass dry matter and ash) in both experiments. The higher values were noted for all the parameters (except gizzard and carcass fat percentages) studied in Experiment 1 compared to those observed in Experiment 2.

• Korean Journal of Poultry Science
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• v.21 no.4
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• pp.267-275
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• 1994

Three dietary ME levels of 3,200, 2,900 and 2,600 kcal /kg in the same 13% single-stage low protein diet were compared to evaluate the effect of ME levels of grower diets on egg-type pullet growth and subsequent laying performance. As the ME levels of grower diets decreased, cumulative feed and protein consumptions increased(P<0.05), however, the ME intake and body weight at 18 wk of age decreased(P<0.05). Grower feed cost decreased as the dietary ME level was decreased, but no significant difference was found among dietary ME levels of grower diets. During the laying period, sexual maturity, hen-day egg production and average egg weight were not significantly affected by the ME levels of grower diet, however, daily feed intake and feed required per egg decreased as the dietary ME level of grower diet was reduced(P<0.05). Results of this study indicate that pullets can be reared on the low ME diet of 2,600 kcal /kg and it would he economical to utilize the low energy diet during the growing period when they are reared on a 13% single-stage low protein diet.

• Journal of Nutrition and Health
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• v.7 no.1
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• pp.45-50
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• 1974

Biochemical studies such as growth rate, blood cholesterol and ascorbic acid contents in various organs of albino male rats were studied in the Garlic, Vitamin E, high and low protein diet fed groups. The results of this study were summarized as follows : 1) Either single 10% or 30% protein diet fed rats were not shown growth rate properly. In supplementation of Vitamin E or Garlic on 30% protein growth rate was a more increased than that of the 10% protein diet group. 2) The rate of food consumption of rats fed a 10% or 30% protein diet supplemented with Vitamin E and Garlic was more increased than that of the control Group receving 10% or 30% protein diet alone. 3) No essential difference was observed between the cholesterol level in blood of rats fed 10% protein diet supplemented with Vitamin E and Garlic and that of rats Receiving 10% protein diet alone. But the cholesterol level in blood of rats fed 30% protein diet supplemented with Vitamin E and Garlic was lower than that of control receiving 30% protein diet alone. 4) The Vitamin C contents in various organs of rats fed the diet supplemented with Vitamin E and Garlic seems to be a little higher than that of the control group fed the protein diet alone.

• Journal of Nutrition and Health
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• v.27 no.1
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• pp.90-99
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• 1994

This study was carried out to examine how dietary protein and calcium levels in rats fed fat-enriched diet affect the total lipid and cholesterol contents of blood and tissues. Male Sprauge-Dawley rats weighing approximately 200g were fed six purified diets which contained 18%(w/w) beef tallow, 1% (w/w) cholesterol, two source of protein, casein or isolated soy protein (ISP) and three levels of dietary calcium, 0.1%, 0.4% and 1.0%, first, for four weeks, and second, for eight weeks. The contents of the total lipid, cholesterol and triglyceride in blood, liver, heart and feces were determined. After four weeks feeding serum lipid and cholesterol concentrations significantly decreased in rats fed 1.0% (w/w) level calcium, regardless of dietrary protein sources. After eight weeks, these concentrations were significantly lower in the rats fed soy protein than in casein-fed rats. As dietary calcium level increased serum and tissue lipid and cholesterol contents were decreased and fecal lipid excretion increased. It is concluded that hypolipidemic and/or hypocholesterolemic effects of soy protein and calcium were partly due to decrease in lipid absorption.

• Biomedical Science Letters
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• v.24 no.3
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• pp.175-182
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• 2018

Aspergillosis is a life-threatening disease in individuals with compromised immune systems. Fungal invasion is a highly critical process during host cellular infection. Several papers have reported that transcription factors are responsible for the infection process. To investigate what transcription factors are involved in the process in an effort to inhibit fungal infection into cells, I checked the surfactant protein family and PU.1 transcription factor levels in A549 cells infected with A. fumigatus conidia. PU.1 and surfactant protein-D levels were reduced in cells infected with fungal conidia. I then observed an increase in surfactant protein-D on PU.1-overexpressed cells. Infection of A. fumigatus conidia was decreased in PU.1-overexpressed cells, whereas the suppression of PU.1 did not lead to any changes in cases of A. fumigatus conidia infection. These results indicate that PU.1 inhibits the infection of A. fumigatus conidia via the expression of surfactant protein-D, suggesting that PU.1 is a key transcription factor for protection against A. fumigatus invasion.

• Journal of Nutrition and Health
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• v.19 no.3
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• pp.211-223
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• 1986

In this experiment forty-eight Sprague Dawley male rats were chosen and used in order to measure the growth rates and to see the effects of lead acumulation in their organs resulting from variously controlled lead protein diet. Protein sources were casein and isolated soyprotein (ISP), and each source was divided into three groups : 7% low protein [LP], 20% standard protein (SP) and 40% high protein (HP) groups. The six experimental groups were given lead acetate(25 mg/kg B.W.) and six control groups were given sodium chloride by oral administration 6 times a week for weeks. The results from this experiment were summeraized as following ; 1) Food consumption, weight gain, organ weight and food efficiency ; Lead acetate administration with protein source had no effects on food consumption, weight gain and organ weight . By their different levels of protein, food consumption of LP group was less the that of SP and HP groups after 3 weeks, weight gain of LP group was less than that of SP and HO groups after 1 weeks. The organ weight in LP group was significantly lower than SP and HP groups except teeth and adrenal s. Effect of lead acetate administration on food efficiency have significantly lower in LP-ISP diet and HP -casein diet than other groups only first week. By their different levels LP group showed significantly lower than SP group until 3 weeks. 2) Hematopoietic effect ; The hematopoieteic effect was not influencec by lead acdtate administration and protein source. But the LP group showed a significantly lowe hematopoietic effect than the SP, HP, groups. 3) Accumulation of lead in the liver, kidney, teeth by protein source showed no significantly differences. Accumulation of lead in blood, heart of LP group, spleen of LP and HP groups. femur of SP and HP groups fed with casein diet groups were significantly higher than fed with ISP diet groups. By their different levels of group showed generally higher than SP and HP groups. But accumulation of lead in teeth of HP group was high also.