Maternal Vitamin D Status and Gestational Weight Gain as Correlates of Neonatal Bone Mass in Healthy Term Breastfed Young Infants from Montreal,Canada

The implications of maternal gestational weight gain (GWG) and vitamin D status to neonatal bone health are unclear. We tested whether maternal 25-hydroxyvitamin D (25(OH)D) and GWG relate to neonatal bone mineral content (BMC) and bone mineral density (BMD). Healthy term appropriate for gestational age breastfed neonates (n = 142) and their mothers were recruited 24–36 h after delivery and followed at 1.0 ± 0.5 month. At birth, obstetric data were collected and newborn serum 25(OH)D was measured. At 1 month, neonatal whole-body (WB) BMC, WB BMC relative to body weight (WB BMC/kg), lumbar spine BMC and BMD, maternal and neonatal 25(OH)D concentrations, and anthropometry were measured. Infant BMC and BMD between maternal 25(OH)D (<50, ≥50 nmol/L) and GWG (insufficient, adequate, and excessive) categories were compared. Maternal 25(OH)D was not related to infant whole-body BMC, BMC/kg, lumbar spine BMC, and BMD. Infants in the excessive maternal GWG category had greater (p = 0.0003) whole-body BMC and BMC/kg and lumbar spine BMC and BMD than inadequate GWG, and greater (p = 0.0063) whole-body BMC/kg and lumbar spine BMC and BMD than adequate GWG. These results suggest that maternal GWG, but not vitamin D status, modestly relates to bone mass in neonates.     

钙、维生素D缺乏对幼鼠骨生长和成骨细胞功能的影响

目的：探讨钙与维生素D营养缺乏对幼鼠骨骼生长和矿化的影响及机制。方法：建立单纯钙缺乏、维生素D缺乏和钙与维生素D同时缺乏的幼鼠动物模型，追踪其长骨的生长发育，并监测血清Ca,P,25-ODH3,骨碱性磷酸酶（B－ALP）水平及骨矿含量的构成的改变；观察反映骨形成和成骨细胞功能的生化标志－血清骨钙素水平。结果：钙缺乏、维生素D缺乏和两者同时缺乏大鼠的长骨生长发育明显落后于正常大鼠；其胫骨重、骨灰重均显著降低；对骨矿成分的分析显示，除K以外Ca,P,Mg,Na均有不同程度减少；实验组大鼠的血清骨钙素水平随实验期延长呈进行性下降。结论：钙和维生素D缺乏影响成骨细胞的功能，使骨形成和矿化过程受阻，从而导致骨骼生长发育质和量的异常。     

Elderly Women Need Dietary Protein to Maintain Bone Mass

Excess dietary protein is considered a risk factor for osteoporosis owing to the potential for renal acid load. Researchers who conducted a recent prospective study of older adults reported that animal protein had a protective role for bone, especially in elderly women, whereas plant protein was negatively associated with bone mineral density. An interaction between protein and calcium suggested protein alone was not the important factor. Other studies confirm the beneficial effect of increasing dietary protein intake in older women to reduce bone mineral density loss and risk of fracture, suggesting that emphasis should be placed on promoting adequate protein intake in elderly women.     

Dietary Habits,Nutrients and Bone Mass in Spanish Premenopausal Women: The Contribution of Fish to Better Bone Health

The moderate consumption of fish is recommended for a healthy diet and is also a feature of the Mediterranean diet. Fish is a major food group in diets throughout the world, and studies show that fish consumption is associated with a lower risk of a number of conditions. Spain has one of the highest annual per capita consumptions of fish worldwide. As fish is a source of high quality protein; n-3 polyunsaturated fatty acids; vitamins, such as A and D; and minerals, such as selenium, calcium, iodine, magnesium, copper and zinc, nutrients that have positive effects on bone characteristics, it has been proposed that its consumption could improve bone health. In this cross-sectional study, we have investigated the relationship between dietary habits and nutrient intake of 151 Spanish premenopausal women and analyzed the association of fish consumption on bone mass measured by quantitative ultrasound of the phalanges. A higher (P < 0.05) bone mass and vitamin D intake (P < 0.05) was observed in the group with a fish intake of 5–7 servings/week. We conclude that increased fish consumption is helpful in maintaining an adequate bone mass in Spanish premenopausal women.     

Dietary Protein,Phosphorus and Potassium Are Beneficial to Bone Mineral Density in Adult Men Consuming Adequate Dietary Calcium

Objective: The purpose of this study was to determine relationships of calcium (Ca), protein (Pr), phosphorus (P) and potassium (K) to measures of bone mineral density in adult men.

Methods: Cross-sectional analysis of 57 men ages 39 to 42 years who were participants in an ongoing study. Dietary assessment was conducted using the Block food frequency questionnaire (FFQ). BMD of total body (TB), hip and lumbar spine (LS) were measured with dual X-ray absorptiometry (DXA).

Results: Ca, Pr, P and K, as well as lean body mass (LBM), showed significant correlation with BMD at the total body, hip and lumbar spine. Stepwise forward regression selection method identified LBM, height and fat mass as significant predictors of TB-BMD, LBM and height as significant predictors of hip BMD, and LBM as a significant predictor of LS-BMD. As the nutrients tested correlated significantly with each other, only one nutrient was entered into the regression model at a time to accommodate the potential for multicollinearity. In regression analysis, adjusted for site-specific anthropometric variables and energy intake, K, Pr and P intake accounted for significant (p < 0.05) prediction of TB-BMD and LS-BMD values by 7% to 13%. No bone-related nutrient added significantly to the prediction of hip BMD. Ca intake was not significantly associated with BMD at any site in the adjusted models.

Conclusions: Our analysis provides support that a moderate protein (1.2 g/kg) diet, plentiful in potassium (>100 mmol/day) and phosphorus (1741 ± 535 mg) is beneficial for maintaining bone mineral density in adult men when Ca intake was adequate (1200 ± 515 mg).     

老年人体内维生素D,PTH和骨矿含量调查

对９８名６５～７５岁的健康退休工人分别用放射免疫分析和免疫放射法测定血浆２５（ＯＨ）Ｄ和ＰＴＨ的含量，应用ＤＰＸ－Ｌ双能骨矿测定仪测定腰椎及髋部ＢＭＣ。结果表明：（１）该人群春季血浆２５（ＯＨ）Ｄ水平较低，男性为１１．４±５．０ｎｇ／ｍｌ，女性为１５．５±５．３ｎｇ／ｍｌ，其水平与腰椎及髋部ＢＭＣ没有关系。（２）老年女性血浆２５（ＯＨ）Ｄ浓度与血浆ＰＴＨ浓度呈负相关，而这种关系在老年男性不存在。（３）老年女性骨面积和体重身高校正后的股骨颈ＢＭＣ与血浆ＰＴＨ浓度呈反向关系，但其它部位ＢＭＣ以及老年男性所有部位ＢＭＣ均与血浆ＰＴＨ浓度无关。     

Increased Plasma Concentrations of Vitamin D Metabolites and Vitamin D Binding Protein in Women Using Hormonal Contraceptives: A Cross-Sectional Study

Use of hormonal contraceptives (HC) may influence total plasma concentrations of vitamin D metabolites. A likely cause is an increased synthesis of vitamin D binding protein (VDBP). Discrepant results are reported on whether the use of HC affects free concentrations of vitamin D metabolites. Aim: In a cross-sectional study, plasma concentrations of vitamin D metabolites, VDBP, and the calculated free vitamin D index in users and non-users of HC were compared and markers of calcium and bone metabolism investigated. Results: 75 Caucasian women aged 25–35 years were included during winter season. Compared with non-users (n = 23), users of HC (n = 52) had significantly higher plasma concentrations of 25-hydroxyvitamin D (25OHD) (median 84 interquartile range: [67-111] vs. 70 [47-83] nmol/L, p = 0.01), 1,25-dihydroxyvitamin D (1,25(OH)₂D) (198 [163-241] vs. 158 [123-183] pmol/L, p = 0.01) and VDBP (358 [260-432] vs. 271 [179-302] µg/mL, p < 0.001). However, the calculated free indices (FI-25OHD and FI-1,25(OH)₂D) were not significantly different between groups (p > 0.10). There were no significant differences in indices of calcium homeostasis (plasma concentrations of calcium, parathyroid hormone, and calcitonin, p > 0.21) or bone metabolism (plasma bone specific alkaline phosphatase, osteocalcin, and urinary NTX/creatinine ratio) between groups. In conclusion: Use of HC is associated with 13%–25% higher concentrations of total vitamin D metabolites and VDBP. This however is not reflected in indices of calcium or bone metabolism. Use of HC should be considered in the interpretation of plasma concentrations vitamin D metabolites.     

Vitamin D Insufficiency and Bone Mineral Status in a Population of Newcomer Children in Canada

Background: Low levels of circulating vitamin D are more likely to be found in those with darker skin pigmentation, who live in areas of high latitude, and who wear more clothing. We examined the prevalence of vitamin D deficiency and inadequacy in newcomer immigrant and refugee children. Methods: We evaluated circulating vitamin D status of immigrant children at the national level. Subsequently, we investigated vitamin D intake, circulating vitamin D status, and total body bone mineral content (TBBMC) in newcomer children living in Saskatchewan. Results: In the sample of newcomer children in Saskatchewan, the prevalence of inadequacy in calcium and vitamin D intakes was 76% and 89.4%, respectively. Vitamin D intake from food/supplement was significantly higher in immigrants compared to refugees, which accords with the significant difference in serum status. Circulating vitamin D status indicated that 29% of participants were deficient and another 44% had inadequate levels of serum 25(OH)D for bone health. Dietary vitamin D intake, sex, region of origin, and length of stay in Canada were significant predictors of serum vitamin D status. Results for TBBMC revealed that 38.6% were found to have low TBBMC compared to estimated values for age, sex, and ethnicity. In the regression model, after controlling for possible confounders, children who were taller and had greater circulating vitamin D also had greater TBBMC. Nationally, immigrant children, particularly girls, have significantly lower plasma 25(OH)D than non-immigrant children. Interpretation: Newcomer immigrant and refugee children are at a high risk of vitamin D deficiency and inadequacy, which may have serious negative consequences for their health.     

Vitamin D and bone health: potential mechanisms

Osteoporosis is associated with increased morbidity, mortality and significant economic and health costs. Vitamin D is a secosteriod hormone essential for calcium absorption and bone mineralization which is positively associated with bone mineral density [BMD]. It is well-established that prolonged and severe vitamin D deficiency leads to rickets in children and osteomalacia in adults. Sub-optimal vitamin D status has been reported in many populations but it is a particular concern in older people; thus there is clearly a need for effective strategies to optimise bone health. A number of recent studies have suggested that the role of vitamin D in preventing fractures may be via its mediating effects on muscle function (a defect in muscle function is one of the classical signs of rickets) and inflammation. Studies have demonstrated that vitamin D supplementation can improve muscle strength which in turn contributes to a decrease in incidence of falls, one of the largest contributors to fracture incidence. Osteoporosis is often considered to be an inflammatory condition and pro-inflammatory cytokines have been associated with increased bone metabolism. The immunoregulatory mechanisms of vitamin D may thus modulate the effect of these cytokines on bone health and subsequent fracture risk. Vitamin D, therefore, may influence fracture risk via a number of different mechanisms.     

Long-Term Vitamin D3 Supplementation Does Not Prevent Colonic Inflammation or Modulate Bone Health in IL-10 Knockout Mice at Young Adulthood

Inflammatory bowel disease (IBD) is an idiopathic disease that can impair bone metabolism. Low vitamin D status has been implicated in its progress. This study used interleukin (IL)-10 knockout (KO) mice, that develop an intestinal inflammation when housed in a non-sterile environment, to determine if supplementation with vitamin D₃ throughout life could mitigate inflammation and attenuate the lower bone mineral content (BMC) and density (BMD), and bone strength. Female IL-10 KO mice were randomized 25 or 5000 IU vitamin D₃/kg diet throughout pregnancy and lactation. At weaning, offspring received the same or opposite diet as their mother until age three months. Body weight growth was similar among groups within a sex. At three months of age, there were no differences in inflammation and gene expression in the colon of offspring. Male offspring exposed to continuous 25 IU vitamin D₃/kg diet had lower (p < 0.001) colonic VDR expression and those exposed only to low vitamin D₃ until weaning had higher serum IL-6. There were no differences in femur or vertebral BMC, BMD or bone strength. In summary, long-term exposure to vitamin D₃ did not attenuate intestinal inflammation or preserve bone mineral or bone strength. Thus, supplementation with vitamin D₃ does not exert anti-inflammatory effects in this mouse model that mimics human inflammatory bowel disease.     

补充钙、维生素D及镁、锌、铜对大鼠骨密度和骨强度的影响

目的观察在补充钙、维生素D的同时补充镁、锌、铜对大鼠骨密度和骨强度的影响。方法30只初始体重65～75g的清洁级断乳Wistar雄性大鼠,根据体重随机分为3组,即低钙饲料对照组、受试物低剂量实验组和高剂量实验组,每组10只。实验周期为12周。测定右侧股骨长度、重量、股骨骨密度及骨钙含量,左侧股骨最大载荷、最大挠度、弹性能量吸收、最大应力、弹性模量。结果低、高剂量实验组大鼠的股骨重量、股骨远心端和股骨中点的骨密度、股骨钙含量、股骨的最大载荷和弹性能量吸收均显著高于低钙对照组(P<0.05)。结论补充钙、维生素D及镁、锌、铜能明显增强大鼠股骨的骨密度、骨强度,提示对延缓骨骼的老化有一定的作用。     

The Relationship between Dietary Pattern and Bone Mass in School-Age Children

Early bone accrual significantly influences adult bone health and osteoporosis incidence. We aimed to investigate the relationship between dietary patterns (DPs), bone mineral content (BMC) and bone mineral density (BMD) in school-age children in China. Children aged six–nine years (n = 465) were enrolled in this cross-sectional study. DPs were identified by principal component factor analysis. Total body (TB) and total body less head (TBLH) BMC and BMD were measured using dual-energy X-ray absorptiometry. Five DPs were identified. After adjustment for covariates, multiple linear regression analysis showed that the “fruit-milk-eggs” dietary pattern was positively associated with TB (β = 10.480; 95% CI: 2.190, 18.770) and TBLH (β = 5.577; 95% CI: 0.214, 10.941) BMC, the “animal organs-refined cereals” pattern was associated with low TB BMC (β = −10.305; 95% CI: −18.433, −2.176), TBLH BMC (β = −6.346; 95% CI: −11.596, −1.096), TB BMD (β = −0.006; 95% CI: −0.011, −0.001) and TBLH BMD (β = −0.004; 95% CI: −0.007, −0.001). In conclusion, our study recommends home or school meals should be rich in fruit, milk, eggs with a moderate amount of vegetables, coarse grains and meat to promote bone development for school-age children.     

Vitamin D Status,Bone Mineral Density,and VDR Gene Polymorphism in a Cohort of Belarusian Postmenopausal Women

Vitamin D plays an important role in bone metabolism and is important for the prevention of multifactorial pathologies, including osteoporosis (OP). The biological action of vitamin is realized through its receptor, which is coded by the VDR gene. VDR gene polymorphism can influence individual predisposition to OP and response to vitamin D supplementation. The aim of this work was to reveal the effects of VDR gene ApaI rs7975232, BsmI rs1544410, TaqI rs731236, FokI rs2228570, and Cdx2 rs11568820 variants on bone mineral density (BMD), 25-hydroxyvitamin D level, and OP risk in Belarusian women. Methods. The case group included 355 women with postmenopausal OP, and the control group comprised 247 women who met the inclusion criteria. TaqMan genotyping assay was used to determine VDR gene variants. Results. Rs7975232 A/A, rs1544410 T/T, and rs731236 G/G single variants and their A-T-G haplotype showed a significant association with increased OP risk (for A-T-G, OR = 1.8, p = 0.0001) and decreased BMD (A-T-G, −0.09 g/cm², p = 0.0001). The rs11568820 A-allele showed a protective effect on BMD (+0.22 g/cm², p = 0.027). A significant dose effect with 25(OH)D was found for rs1544410, rs731236, and rs11568820 genotypes. Rs731236 A/A was associated with the 25(OH)D deficiency state. Conclusion. Our novel data on the relationship between VDR gene variants and BMD, 25(OH)D level, and OP risk highlights the importance of genetic markers for personalized medicine strategy.     

锌、钙和维生素D对生长期大鼠骨密度影响的实验研究

【目的】探讨微量元素锌(zinc,Zn),元素钙(calcium,Ca)和维生素D(vitamin D,VitD)缺乏对生长期大鼠骨密度、骨质厚度的影响。【方法】选择Wistar大鼠,喂予不同营养成份的人工合成饲料,建立不同的营养缺乏动物模型。测量各组大鼠体重和身长变化,血浆微量元素含量,血清骨碱性磷酸酶(bone alkaline phosphatase,BALP),胫骨骨密度CT值,骨质厚度。【结果】10周实验结束时,低Ca组血浆Ca含量降低(P<0.01),缺VitD组与缺Zn组的血浆Ca含量无变化(P>0.05);缺VitD组与缺Zn组的血浆微量元素Zn含量降低(P<0.01和<0.05),两组之间差异无显著性(P>0.0 5),低Ca组血浆微量元素Zn含量无变化(P>0.0 5);缺VitD组,低Ca组,缺Zn组BALP均明显升高(P<0.01),三组间差异无显著性(P>0.05)。缺VitD组、低Ca组、缺Zn组的骨密度CT值降低(P<0.01),缺Zn组的骨密度CT值低于缺VitD组和低Ca组(P<0.01);缺VitD组与低Ca组的骨密度CT值降低的程度基本相同(P>0.05)。缺VitD组与缺Zn组骨质厚度明显变薄(P<0.01),两组之间差异无显著性(P>0.05);低Ca组骨质厚度也变薄、但变化不明显(P>0.05)。【结论】Zn,VitD,Ca的缺乏或不足都可以造成骨密度降低、骨质厚度变薄、BALP升高。     

维生素D及钙营养缺乏对雏鸡骨骼发育影响

目的 建立ＶｉｔＤ缺乏、钙缺乏雏鸡动物模型,比较两种情况下骨生长情况。分析两种营养素对骨骼发育的影响。方法 建立动物模型。采用反相高效液相色谱法、离子电极测量技术、双维骨密度测定仪、原子吸收分光光度仪分别测血维生素Ｄ、离子钙、骨密度、骨钙含量等。结果 单纯钙缺乏和ＶｉｔＤ缺乏组雏鸡其骨密度、骨矿含量、骨含钙量、骨宽、骨长、骨重均低于正常组,以ＶｉｔＤ缺乏组降低尤为明显,且其生长板软骨明显增厚,软骨     

儿童青少年时期钙和维生素D营养状况对成年后骨骼健康的影响

包括钙和维生素D在内的膳食因素是影响峰值骨量的重要环境因素，增加生长发育期的峰值骨量是延缓成年后发生骨质疏松症的重要措施。本文综述儿童青少年时期的膳食因素对峰值骨量及成年后骨骼健康的影响。     

联合补充不同剂量钙、镁、铜、锌和维生素D对中老年妇女骨质疏松症的防治效果

目的观察联合补充钙、镁、锌、铜及维生素D对中老年妇女骨密度和骨钙索的影响，以及改善骨症状的效果。方法依据人选和排除标准，在上海地区筛选出中老年妇女230人，随机分成干预组和对照组，各组再分为未绝经与绝经组。干预组A：未绝经妇女75名；对照组A：未绝经妇女40名；干预组B：已绝经妇女78名；对照组B：已绝经妇女37名。干预组每日服用2片钙尔奇添佳片（每片含钙273．5mg、VitD1．62μg、镁99．7mg、锌3．08mg、铜0．51mg），干预6个月后再进一步分成低剂量亚组和高剂量亚组，每日服用2或3片钙尔奇添佳片，再干预6个月，总计干预12个月。所有入选者在研究前后各阶段检测腰椎骨密度（BMD）及血清骨钙素（BGP），并进行24小时膳食回顾调查和记录骨症状改善情况。结果（1）骨密度：研究6个月后，干预组腰椎骨密度值较前无显著差异（P〉0．05）。研究12个月后，未绝经干预组骨密度显著增加，未绝经对照组腰椎骨密度则呈显著性下降，但已绝经干预组和对照组的骨密度研究前后无显著变化（P〉0．05）。不同剂量干预亚组骨密度间无显著差异（P〉0．05）。（2）骨钙素：研究6及12个月后各组骨钙素水平均明显降低（P〈0．05）；但干预组血清骨钙素水平均明显高于对照组，差异有显著性（P〈0．05）。不同剂量干预亚组的血清骨钙素浓度间无显著差异（P〉0．05）。（3）骨症状：干预后能明显改善局部关节痛和腰背痛等骨症状。结论联合补充钙、镁、锌、铜及维生素D可明显增加未绝经妇女的骨密度和骨钙索，有效改善骨症状；并可明显改善已绝经妇女骨钙素及骨症状，但骨密度改善不明显。低剂量亚组与高剂量亚组的骨质疏松防治效果问无显著性差异。建议中老年妇女尽早补充与骨营养有关的营养素以防治骨质丢失。     

Suboptimal Plasma Vitamin C Is Associated with Lower Bone Mineral Density in Young and Early Middle-Aged Men: A Retrospective Cross-Sectional Study

Background: This study was conducted to evaluate associations between bone mineral density (BMD) and four selected circulating nutrients, particularly vitamin C, among adults aged 20–49 years. Methods: In this retrospective cross-sectional study, the lumbar spine BMD of 866 men and 589 women were measured by dual-energy X-ray absorptiometry and divided into tertiles, respectively. Logistic regressions were used to identify the predictors of low BMD by comparing subjects with the highest BMD to those with the lowest. Results: Multivariate logistic regressions identified suboptimal plasma vitamin C (adjusted odds ratio (AOR) 1.64, 95% confidence interval (CI) 1.16, 2.31), suboptimal serum vitamin B12 (AOR 2.05, 95% CI 1.02, 4.12), and low BMI (BMI < 23) (AOR 1.68, 95% CI 1.12, 2.53) as independent predictors for low BMD in men. In women, low BMI was the only independent predictor for low BMD. Plasma vitamin C, categorized as suboptimal (≤8.8 mg/L) and sufficient (>8.8 mg/L), was positively significantly correlated with the lumbar spine BMD in men, but there was no association in women. Conclusions: Plasma vitamin C, categorized as suboptimal and sufficient, was positively associated with the lumbar spine BMD in young and early middle-aged men. A well-designed cohort study is needed to confirm the findings.     

Bone density,calcium intake and vitamin D status in South Asian women living in Auckland,New Zealand

Aim: To investigate the bone health and associated risk factors of a group of South Asian women living in New Zealand. Studies on the Indian subcontinent suggest a high incidence of low bone mineral density in women with poor vitamin D status and low dietary calcium intake. Methods: Subjects were women of South Asian origin (n = 91) living in Auckland, New Zealand. Subjects were stratified by menopausal status. They completed a 4-day food diary, and provided a fasting blood sample. Bone mineral density was measured in the lumbar spine and proximal femur using dual X-ray densitometry. Results: Mean age of premenopausal (n = 71) and postmenopausal (n = 20) women was 39.8 ± 7.8 and 55.3 ± 5.4 years, respectively. Osteoporosis (T-score ≤−2.5) was present in 32% of postmenopausal and 3% of premenopausal subjects, but only in the lumbar spine. Adequate 25(OH)D levels (>50 nmol/L) were found in only 22% of premenopausal, and 26% of postmenopausal women. A body mass index in the overweight or obese category was found in 61% of premenopausal and 75% of postmenopausal women. Conclusion: The high incidence of osteoporosis in the postmenopausal group could be associated with the early age of oophorectomy or menopause together with low vitamin D status.     

维生素D与骨的生长和矿化

维生素D通过调节肠道和肾脏对钙磷的吸收和重吸收、骨钙的转移来调控矿物质的生理平衡 ,调节骨的矿化和生长。 1,2 5 (OH) 2 D3是活性最强的维生素D代谢产物 ,通过维生素D受体来发挥作用 ,体内还有一种细胞膜相关性快反应类固醇结合蛋白路径 ,通过基因和非基因两条路径维生素D调节和控制着骨的生长和矿化