• Journal of Nutrition and Health
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• 제28권5호
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• pp.415-425
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• 1995

This study was performed to investigate the effect of dietary protein level on the metabolic changes of Ca and skeletons in postmenopausal women, using ovariecotomized rats as an animal model. The female rats of 200∼250g were fed either 8%(L) or 50%(H) casein diet for 15 weeks(1st experiment). At 15th week, the rats of each diet group were undergone ovariectomy or sham-operation and they were continued to feed the same experimantal diet for 9 more months(2nd experiment). Ca metabolism, kidney function and bone composition were determined at the end of 1st experiment, 3rd and 9th month of 2nd experiment. After 1st experiment, high protein group showed higher urinary Ca and protein excretion, however, there was no difference in GFR and urinary hydroxyproline excretion. The weights, ash and Ca content of femur, scapular and vertebra tended to be higher in high protein groups which tells that high protein promoted skeletal growth. In 2nd experiment, high protein group showed higher urinary Ca and protein excretion and lower Ca absorption and balance. GFR was not affected by dietary protein and ovariectomy but increased with time, as well as kidney weight which shows the continuous development of kidney at this age of 15 month in rats. There were no difference in urinary hydroxyproline, serum ALP, and PTH among experimental groups. The weights of femur, scapular, 4th vertebra increased with time, showing the skeleton continues to grow at this age in rats. However, Ca contents, Ca/wt, Ca/ash were decreased with time and tended to be lower in high protein group especially in femur. In conclusion, prolonged feeding of high protein diet deteriorated Ca metabolism and induced bone loss as time after menopause is extended.

• Journal of Nutrition and Health
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• 제42권4호
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• pp.309-317
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• 2009

As far as we know, there were no studies of the effect of L-arginine on bone metabolism in post-menopausal women or ovariectomized rats. The primary objective of the current study was to determine whether arginine supplementation was associated with alterations in femoral and spinal bone mineral density (BMD) and bone markers in ovariectomized (Ovx) rats. Forty female Sprague-Dawley rats were divided into two groups, Ovx and sham groups, which were each randomly divided into two subgroups that were fed control and arginine supplemented diet. All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone formation was measured by serum osteocalcin and alkaline phosphatase (ALP) concentrations. Bone resorption was measured by deoxypyridinoline (DPD) crosslinks immunoassay and corrected for creatinine. Serum osteocalcin, growth hormone, insulin-like growth factor-1 (IGF-1), parathyroid hormone (PTH) and calcitonin were analyzed using radioimmunoassay kits. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXImus (GE Lunar Co, Wisconsin, USA) in spine and femur. The serum and urine concentrations of Ca and P were determined. The plasma was analyzed for arginine. Diet did not affect weight gain, mean food intake, and plasma arginine concentration. Urinary Ca excretion was decreased by arginine supplementation in Ovx rats, but statistically not significant. The Ovx rats fed arginine-supplemented diet were not significantly different in ALP, osteocalcin, crosslinks value, PTH, calcitonin and IGF-1 compared to those fed control diet. The arginine-supplemented group had significantly higher serum Ca and growth hormone than control group. Spine and femur BMD were significantly increased by arginine supplementation on 5th and 9th weeks after feeding. Our findings indicate that dietary L-arginine supplementation decreased bone mineral density loss in Ovx rats. Therefore, dietary arginine supplementation may represent a potentially useful strategy for the management of osteoporosis.

• Asian-Australasian Journal of Animal Sciences
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• 제20권5호
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• pp.706-710
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• 2007

This study was to investigate the caponization effects on bone characteristics in male chickens, and the optimum testosterone implantation dosage on bone characteristics improvement. Healthy Single Comb White Leghorn cockerels were caponized at 12-wk-old and selected at 16-wk-old for a 10-wk feeding experiment. Fifteen intact male and caponized male chickens (capon) respectively were assigned to trial 1. Ten sham-operated chickens and 40 capons (randomly allocated into four treatments) were implanted with cholesterol (1.62 mm i.d., 3.16 mm o.d., $9.24{\pm}0.36$ mg), low (1 mm i.d., 3 mm o.d., $5.88{\pm}0.23$ mg), medium (1.62 mm i.d., 3.16 mm o.d., $9.81{\pm}0.17$ mg) or high dose (2 mm i.d., 4 mm o.d., $16.7{\pm}0.24$ mg) of testosterone in trial 2. The results from trial 1 showed that the tibia length, relative tibia weight, breaking strength, bending moment and stress in intact males were higher than capons (p<0.05). The blood phosphorus concentration in capons was higher than the intact male chickens (p<0.05). Caponization also resulted in more antrums and osteoclasts within periosteum and cortical bone from histological observation. In trial 2, the adverse impact of caponization on the bone breaking strength, bending moment and stress could be alleviated through medium dose testosterone implantation. It appears that caponization reduced androgen secretion hence influenced the biomechanical characteristics of bone (tibia) and these adverse effects could be alleviated through appropriate dose of testosterone implantation.

• 한국식품조리과학회지
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• 제21권5호
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• pp.725-732
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• 2005

본 연구에서는 대두 이소플라본이 난소를 절제한 성장기 흰쥐의 골격 발달에 미치는 영향을 알아보기 위하여 3주령 된 Wister 암컷 쥐를 난소절제한 후 8주 동안 genistein을 경구 투여하여 골대사에 미치는 일반지표 및 생화학지표를 관찰하였다. 1. 체중 증가는 OVX군$(230.2{\pm}25.15\;g)$이 SH군$(170.6{\pm}20.51\;g)$에 비해 유의적으로 높게 나타났으나 (p<0.05), OVX+GEN군과 OVX+ES군의 체중 증가는 OVX군에 비해 유의적인 차이를 보이지 않았다. 2. 체중 당 간과 자궁의 무게는 난소를 절제한 모든군에서 SH군에 비해 유의적으로 낮았으며(p<0.05), 신장의 무게 또한 SH군에 비해 난소를 절제한 모든 군에서 유의적으로(p<0.05) 감소하였으나 난소절제군 사이에서 유의적인 차이는 없었다. 3. 대퇴골의 무게는 모든 군간에서 유의적인 차이는 없었으나 대퇴골의 길이는 SH군에 비해 OVX군에서 길게 나타났다. 4. 뇨 중 creatinine의 양은 난소 절제군에서 모두 증가하였으나 유의적인 차이는 나타나지 않았다. 또한 hydroxyproline 함량도 모든 군간에서 차이가 나타나지 않았다. 5. 혈청 ALP 활성은 모든 군에서 차이가 없었으며 대퇴골, 변, 혈청, 뇨에서의 Ca의 함량도 모든 군간에서 유의적인 차이가 없었다. 6. 대퇴골의 골밀도는 SH군에 비해 난소를 절제한 군에서 낮았으며 genistein 투여로 다시 증가하는 경향을 보였으나 유의적인 차이는 없었다. 파단력과 stiffiness의 경우 난소 절제 및 genistein 처리에 의한 영향을 받지 않았다. 본 결과를 통하여 genistein에 의한 투여는 난소를 절제한 성장기의 흰쥐에서도 최대골질량을 유지하고 골질량의 손실을 억제할 수 있는 효과가 있어 성장기 동안의 섭취가 골다공증 예방에 효과가 있을 것으로 예상된다.