• 제목/요약/키워드: Calcium

검색결과 8,445건 처리시간 0.146초

작물의 생합성 칼슘 함량 증대 연구 현황 (Current status in calcium biofortification of crops)

  • 이정여;노일섭;김혜란
    • Journal of Plant Biotechnology
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    • 제39권1호
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    • pp.23-32
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    • 2012
  • Calcium is an essential nutrient for living organisms, with key structural and signaling roles. Its deficiency in plants can result in poor biotic and abiotic stress tolerance as well as reduced crop quality and yield. Calcium deficiency in humans causes various diseases such as osteoporosis and rickets. Biofortification of calcium in various food crops has been suggested as an economic and environmentally advantageous method to enhance human intake of calcium. Recent efforts to increase the levels of calcium in food crops have used calcium/proton antiporters ($CAXs$) and modified one to increase calcium transport into vacuoles through genetic engineering. It has been reported that overall calcium content of transgenic plants has been increased in their edible portions with some adverse effects. In conclusion, biofortification of calcium will add more value in crops as well as will be beneficial for animal and human. Therefore, more fundamental studies on the mechanisms of calcium ion storage and transporting are essential for more effective calcium biofortification.

Thimerosal generates superoxide anion by activating NADPH oxidase: a mechanism of thimerosal-induced calcium release

  • Kim, Eui-Kyung;Ryu, Sung-Ho;Suh, Pann-Ghill
    • 한국환경성돌연변이발암원학회지
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    • 제22권4호
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    • pp.229-235
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    • 2002
  • Thimerosal, a widely used preservative, has been well known to induce intracellular calcium mobilization in various cell types. However, the mechanism of its calcium mobilization is not clearly understood yet. For studying the mechanism of thimerosal-mediated calcium release, we have used HL60 cells in calcium-free Lockes solution that has no extracellular calcium. Thimerosal significantly reduced the lag period of initial calcium release whereas it enhanced the rate and magnitude of the calcium release in a dose-dependent manner. At the same time, we found that thimerosal generated superoxide anion by activating NADPH oxidase in dose- and time-dependent manner. Interestingly, the kinetics and the dosedependency of superoxide anion generation were very similar to those of intracellular calcium mobilization. In inhibitors study, the thimerosal-induced superoxide anion generation was significantly suppressed by DMSO as well as superoxide dismutase but not by genistein or EGTA. Surprisingly, the pretreatment with N-Acetyl-$_{L}$-Cysteine blocked almost completely the thimerosal-induced calcium increase, indicating that ROS playa key role in the calcium mobilization. The present results suggest that thimerosal-induced calcium mobilization is possibly mediated by the activation of NADPH oxidase and subsequent ROS generation.n.

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난소절제한 흰쥐에서 식이칼슘량이 골밀도에 미치는 영향 (The Effect of Dietary Calcium Level on Bone Mineral Density and Bone Mineral Content in Ovariectomized Female Rats)

  • 김경희
    • Journal of Nutrition and Health
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    • 제29권6호
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    • pp.590-593
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    • 1996
  • This study was done to evaluate the effect of dietary calcium level (a diet which met 100% or twice the calcium level in AIN-76 diet) on preventing bone loss in ovariectomized rats. Forty Sprauge-Dawley female rats(body weight 200$\pm$5g)were divided into two groups. One group were ovariecotomized (Ovx) while the others received sham operation(Sham). Thereafter, each rat group was further divided into normal calcium diet(0.52%) and high calcium diet(1.04%) subgroups. All rats were fed on experimental diet and deionized water ad libitum for 8 weeks. The total body, spine and femur bone mineral densities and bone mineral contents were measured by Dual Energy X-ray Absorptiometry, Eight weeks following operation, ovariectomized rats fed a high calcium diet had a significantly higher total bone mineral content, total bone calcium content, spine bone mineral density, spine bone mineral content and femur bone mineral content than ovariectomized rats fed control calcium diet. The correlation between dietary calcium intake level and spine bone mineral density were positive, but there was no correlation between dietary calcium intake and femur bone mineral density. The findings from the present study demonstrated that bone loss due to ovarian hormonal deficiency can be partially prevented by a high calcium diet. Futhermore, these findings support the strategy of the use of a high calcium diet in the prevention of estrogen depleted bone loss(postmenopausal osteoporosis)

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갱년기 여성의 칼슘보충제 섭취가 혈청 칼슘 농도와 심리상태에 미치는 영향 (Effect of Ca Supplementation on Serum Ca Level and Psychological Conditions in Perimenopausal Women)

  • 홍순명;김현주
    • 대한지역사회영양학회지
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    • 제6권4호
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    • pp.628-634
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    • 2001
  • This study was conducted to investigate the relationship of serum calcium and magnesium level to depression and anxiety symptoms in 66 perimenopausal women. Daily nutrient intakes and dietary sources of calcium were analyzed by convenient me쇙. General status was conducted by a questionnaire whereas the questionnaire of CED-S(the Center for Epidemiological studies-Depression Scale) was used for depression and Spielburger's STAI-S(state-Trait Anxiety Inventory-State) was used for anxiety. Fasting blood samples were collected, and serum calcium and magnesium concentrations were measured before and after calcium supplementation. The age distribution of the subjects was 49-55 years. Results indicated that serum calcium concentrations were significantly(P〈0.05) increased to normal ranges after calcium supplementation. Depression and anxiety scores of the subjects with calcium supplementation were significantly(p〈0.05) lower than those before calcium supplementation. There were significantly(P〈0.05) decreased between serum magnesium concentration and depression and anxiety scores, but calcium concentration was not significantly decreased. These results suggest that psychological conditions of perimenopausal women are possibly effected by serum calcium and magnesium levels. More studies are needed to measure the long-term effects of calcium supplementation on psychological conditions in perimenopausal women.

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칼슘의 섭취수준이 암쥐의 체내 철분이용에 미치는 영향 (Effect of Dietary Calcium Levels on Iron Utilization in Female Rat)

  • 승정자
    • 한국식품영양과학회지
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    • 제25권6호
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    • pp.1016-1023
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    • 1996
  • 칼슘의 섭취수준이 체내 철분이용에 미치는 영향을 알아보기 위하여 생후 4주된 암쥐를 대상으로 요구량의 50%, 100%, 200% 수준의 식이 칼슘을 3주간 공급한 후 헤모글로빈 함량, 헤마토크릿, 혈청과 조직의 칼슘과 철분 함량, 칼슘과 철분 평형을 살펴 본 결과는 다음과 같다. 사료 섭취량, 체중 증가량, 사료 효율, 헤모글로빈 함량, 헤마토크릿, 혈청과 조직의 칼슘과 철분 함량은 칼슘 섭취수준에 따른 각 군별 유의적인 차이가 없었다. 그러나 고칼슘군의 신장 칼슘 함량은 저칼슘군이나 적정칼슘군 보다 유의하게 높았다(p<0.01). 칼슘의 섭취수준 증가에 따라 소변과 대변을 통한 칼슘 배설량과 칼슘 보유량은 유의하게 높았으나(p<0.05, p<0.01, p<0.001) 칼슘 보유율은 유의적으로 낮은 것으로 나타났다(p<0.001). 철분 섭취량은 칼슘 섭취수준에 따른 유의한 차이가 있어 (p<0.001) 적정 칼슘군이 저칼슘군과 고칼슘군 보다 유의하게 높았다. 소변과 대변을 통한 철분 배설량도 칼슘 섭취수준에 따른 영향을 받아(p<0.01, p<0.05) 저 칼슘군의 철분 배설량이 적정 칼슘군이나 고칼슘군 보다 유의하게 낮은 것으로 나타났다. 철분과 섭취량, 소변과 대변을 통한 배설량으로 산출한 철분의 보유량, 보유율은 칼슘의 섭취수준에 따른 각 군별 유의적인 차이가 있어(p<0.05, p<0.05) 고칼슘군이 저 칼슘군이나 적정 칼슘군보다 유의하게 낮았다. 이상의 결과로 요구량의 2배 정도의 칼슘 섭취 수준에서 칼슘의 체내 보유량은 증가하지만 철분의 평형은 약간 감소한 것으로 나타남으로써 칼슘보충제의 섭취시에는 칼슘이 외의 다른 무기질의 상호작용에 의한 변화를 고려해야 할 것으로 생각한다.

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Increase in Intracellular Calcium is Necessary for RANKL Induction by High Extracellular Calcium

  • Jun, Ji-Hae;Kim, Hyung-Keun;Woo, Kyung-Mi;Kim, Gwan-Shik;Baek, Jeong-Hwa
    • International Journal of Oral Biology
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    • 제30권1호
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    • pp.9-15
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    • 2005
  • Recently, we reported that high extracellular calcium increased receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL) expression via p44/42 mitogen-activated protein kinase (p44/42 MAPK) activation in mouse osteoblasts. However, the mechanism for p44/42 MAPK activation by high extracellular calcium is unclear. In this study, we examined the role of intracellular calcium increase in high extracellular calcium-induced RANKL induction and p44/42 MAPK activation. Primary cultured mouse calvarial osteoblasts were used. RANKL expression was highly induced by 10 mM calcium treatment. Ionomycin, a calcium ionophore, also increased RANKL expression and activated p44/42 MAPK. U0126, an inhibitor of MEK1/2, an upstream activator of p44/42 MAPK, blocked the RANKL induction by both high extracellular calcium and ionomycin. High extracellular calcium increased the phosphorylation of proline-rich tyrosine kinase 2 (Pyk2), one of the known upstream regulators of p44/42 MAPK activation. Bisindolylmaleimide, an inhibitor of protein kinase C, did not block RANKL induction and p44/42 MAPK activation induced by high extracellular calcium. 2-Aminoethoxydiphenyl borate, an inhibitor of inositol 1,4,5-trisphosphate (IP3) receptor, blocked the RANKL induction by high extracellular calcium. It also partially suppressed the activation of Pyk2 and p44/42 MAPK. Cyclosporin A, an inhibitor of calcineurin, also inhibited high calcium-induced RANKL expression in dose dependent manner. However, cyclosporin A did not affect the activation of Pyk2 and p44/42 MAPK by high extracellular calcium treatment. These results suggest that 1) the increase in intracellular calcium via IP3-mediated calcium release is necessary for RANKL induction by high extracellular calcium treatment, 2) Pyk2 activation, but not protein kinase C, following the increase in intracellular calcium might be involved in p44/42 MAPK activation, and 3) calcineurin-NFAT activation by the increase in intracellular calcium is involved in RANKL induction by high extracellular calcium treatment.

Nutrition knowledge, outcome expectations, self-efficacy, and eating behaviors by calcium intake level in Korean female college students

  • Kim, Min Ju;Kim, Kyung Won
    • Nutrition Research and Practice
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    • 제9권5호
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    • pp.530-538
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    • 2015
  • BACKGROUND/OBJECTIVES: Calcium is important but deficient in diets of young adult women. This study aimed to examine if cognitive factors and eating behaviors differ according to calcium intake based on the Social Cognitive Theory. SUBJECTS/METHODS: Subjects were female college students in Seoul, Korea. Three hundred students completed the questionnaire regarding calcium intake, nutrition knowledge, outcome expectations, self-efficacy and eating behaviors. Data on 240 students were analyzed using t-test or ${\chi}^2$-test. Subjects were categorized into two groups, high calcium intake (HC, ${\geq}650mg/day$) and low calcium intake (LC, < 650 mg/day), according to recommended intakes of calcium for women aged 19-29 years. RESULTS: The LC group constituted 77.9% of total subjects. Nutrition knowledge was not different according to calcium intake. Three out of 12 outcome expectations items were significantly different between the HC and LC groups. Subjects in the HC group agreed more strongly with the practical benefits of consuming calcium-rich foods, including 'taste' (P < 0.01) and 'going well with other snacks' (P < 0.05), compared to those in the LC group. Negative expectations of 'indigestion' were stronger in the LC group than HC group (P < 0.001). Among self-efficacy items, perceived ability of 'eating dairy foods for snacks' (P < 0.001), 'eating dairy foods every day' (P < 0.01), and 'eating calcium-rich side dishes at meals' (P < 0.05) differed significantly between the HC and LC groups. Eating behaviors including more frequent consumption of dairy foods, fruits or fruit juice (P < 0.001), anchovy, seaweeds, green vegetables, protein-rich foods (P < 0.05), and less frequent consumption of sweets or soft drinks (P < 0.01) were significantly related to calcium intake. CONCLUSIONS: This study found that outcome expectations, self-efficacy in consuming calcium-rich foods, and eating behaviors are important in explaining calcium intake. Nutrition education needs to address practical benefits, reduce negative expectations of calcium-rich foods, increase self-efficacy, and modify eating behaviors contributing to calcium intake.

성장기 동안 저칼슘식이를 섭취한 흰쥐에서 난소절제 및 칼슘 섭취량이 골격대사에 미치는영향 (Effect of Ovariectomy and Dietary Calcium Levels on Bone Metabolism in Rats Fed Low Calcium Diet during Growing Period)

  • 이연숙
    • Journal of Nutrition and Health
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    • 제31권3호
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    • pp.279-288
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    • 1998
  • This study explored the effect of calcium levels and/or ovariectomy on bone metabolism using female Sprague-Dawley weanling rats as a model . Rats received a low (0.1%) calcium diet for 8 weeks. The rats were then divided into three subgroups that were fed 0.1% ,0.5% and 1.5% calcium diets for 8 weeks after operation. The results of this experiment indicate that body weight gin was higher in ovariectomy groups than in sham groups regardless of calcium level and food intake. Serum Ca and P concentrations were of normal level regardless of calcium level and ovariectomy. Estrogen concentration was low in the ovariectomized group. Serum alkaline phophatase activity and urinary hydroxyproline have been used as markers of bone formation and resorption. These values were increased in ovariectomized groups. The weight, length and breaking force of femur were not significantly different between the groups. Ash, Ca, P and total lipid contents in femur and lumbar were decreased in the groups fed low calcium . Mg content was decreased in the ovariectomy and total protein content was not affected by calcium level and ovariectomy. The effect groups of ovarectomy on calcium contents of bone was more prominent in lumbar than in femur. In conclusion, though low calcium intakes during growth period may retard the attainment of peak bone mass, calcium supplementation after this period increased bone growth and mineral contents, but not significant effect in three calcium levels. Furthermore, calcium intake was shown to have a greater influence on the mineral contents of femur than of lumbar, and removal of endogenous estrogen production by ovariectomy was shown to be more deleterious on the ash and calcium contents of the lumbar than of femur.

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Fluoride and Calcium in Tea Leaves

  • Takiyama, Kazuyoshi;Ishii, Yuuko
    • 분석과학
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    • 제8권4호
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    • pp.877-880
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    • 1995
  • The determination of fluoride and the nutritious calcium in infusion of teas are explained. Tea leaves were pulverized and were immersed in boiling water. The solution was filtered and fluoride, calcium and oxalic acid were determined by the ion chromatography. The quantities of fluoride, calcium and oxalate ions extracted from 100 g of tea leaves were calculated. Tea leaves were also immersed in 0.5 M hydrochloric acid and extracted oxalate and calcium ions were analyzed. The free oxalic acid and calcium were extracted in boiling water and the total ones were extracted in hydrochloric acid. The quantity of calcium oxalate was calculated from the total and the free oxalic acids. The free calcium was estimated to be nutritious.

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정상인과 고혈압 환자의 식이 Calcium 섭취빈도와 혈청의 Calcium 수준과 지질조성의 비교 (Serum Total Calcium, Ionized Calcium Ion and Lipid Compositions in Hypertensive Koreans)

  • 박광희
    • Journal of Nutrition and Health
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    • 제22권6호
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    • pp.476-484
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    • 1989
  • An epidemiological survey was made on dietary calcium intake, serum total calcium and ionized calcium ion, and serum lipid compositions. Compared with 120 normotensive controls, 101 hypertensive subjects were significantly higher in the levels of serum cholesterol and triglyceride, but lower in HDL-cholesterol and higher in the ratio of total choesterol/HDL-chol Hypertensive subjects were also significantly lower in the relative amount of fatty acids C18:2 but higher in those of C20:0, C20:2 and total amount of saturated fatty acids(longer than C14:0) than control serum. Patients were significantly lower in serum total calcium and ionized calcium ion concentrations and significantly less calcium ingestion from milk and dairy produces by feeding frequency test.

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