IMPACT OF A PROTEIN SUPPLEMENT ON BONE MASS IN OLDER WOMEN

蛋白质补充剂对老年女性骨量的影响

基本信息

批准号：
7485048
负责人：
KARL Leonard INSOGNA
金额：
$ 44.56万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-09-28 至 2010-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7485048
关键词：
3-Dimensional Accounting Acidosis Acids Affect Age Age-Related Bone Loss American Anabolism Bone Density Bone Resorption Calcium Clinical Research Connecticut Control Groups Data Diet Dietary Proteins Double-Blind Method Enrollment Epidemiologic Studies Excretory function Growth Factor Health Hip region structure Homeostasis Hormonal Human Insulin Insulin-Like Growth Factor I Intake Intestines Kinetics Long-Term Effects Measurement Measures Metabolic Metabolism Methodology Minerals Mixed Function Oxygenases Osteoporosis Outcome Outcome Measure Pathogenesis Performance Physical assessment Placebo Control Placebos Play Population Prevention Protein-Restricted Diet Proteins Randomized Range Rate Recommendation Recruitment Activity Research Personnel Risk Role Serum Skeletal system Spinal Supplementation Testing Universities Vertebral column Woman X-Ray Computed Tomography absorption base bone bone health bone loss bone metabolism bone turnover density falls good diet improved indexing maltodextrin novel therapeutics nutrition older women programs trend two-dimensional urinary

项目摘要

DESCRIPTION (provided by applicant): Osteoporosis and osteopenia are major health problems affecting over 44 million Americans, primarily older women. Nutrition, plays a critical role in bone health but its role in the pathogenesis and prevention of bone loss is incompletely understood. We have found that dietary protein is a major regulator of calcium homeostasis, yet its impact on skeletal health remains controversial. Increasing dietary protein is known to increase urinary calcium excretion and a widely held view is that this extra calcium originates, in part, from bone. However, recent epidemiologic studies have found that higher protein intakes are associated with higher (not lower) bone mineral density and lower (not higher) rates of bone loss. Using calcium kinetic methodology, we have found that when dietary protein is increased in healthy women, intestinal calcium absorption increases significantly and accounts for almost all of the increase in urinary calcium. Further, when women consumed a high protein diet, the percentage of urinary calcium originating from bone is reduced and bone turnover is also slightly reduced. We hypothesize that a protein supplement added to the diets of healthy older women with habitually a low-normal protein diet, will improve bone health and hormonal indices of bone metabolism (in comparison to a placebo control). To test this hypothesis, we will conduct an 18-month, double-blind, placebo-controlled, dietary protein supplementation trial using the General Clinical Research Centers at Yale University and the University of Connecticut Health Center. Two hundred healthy women at least 60 yrs. of age will be recruited from central Connecticut. Subjects will be enrolled who naturally consume a moderately low (yet adequate) level of dietary protein (0.6-1 g/kg). (Approximately 30-40% of US women over the age of 60 y fall into this group). After baseline measurements, subjects will be randomized to receive either a placebo (maltodextrin) or a 40 g protein supplement for 18 months. The primary outcome measure in this trial is spinal bone density as assessed by DEXA. Secondary outcomes will include BMD at the spine and hip measured by QCT, serum measures of mineral homeostasis and bone turnover, and an assessment of physical performance. These studies will better inform dietary protein recommendations for optimal skeletal health and, if our hypothesis is correct, provide a new therapeutic approach to age-related bone loss.

描述（由申请人提供）：骨质疏松症和骨质减少是影响超过 4400 万美国人（主要是老年女性）的主要健康问题。营养在骨骼健康中起着至关重要的作用，但其在骨质流失的发病机制和预防中的作用尚不完全清楚。我们发现膳食蛋白质是钙稳态的主要调节剂，但其对骨骼健康的影响仍然存在争议。众所周知，增加膳食蛋白质会增加尿钙排泄，人们普遍认为，这种额外的钙部分来自骨骼。然而，最近的流行病学研究发现，较高的蛋白质摄入量与较高（而不是较低）的骨矿物质密度和较低（而不是较高）的骨质流失率相关。使用钙动力学方法，我们发现，当健康女性增加膳食蛋白质时，肠道钙吸收显着增加，并且几乎占尿钙增加的全部。此外，当女性食用高蛋白饮食时，来自骨骼的尿钙百分比会减少，骨转换也会略有减少。我们假设，在习惯性低正常蛋白质饮食的健康老年女性的饮食中添加蛋白质补充剂，将改善骨骼健康和骨代谢的激素指数（与安慰剂对照相比）。为了检验这一假设，我们将利用耶鲁大学综合临床研究中心和康涅狄格大学健康中心进行为期 18 个月的双盲、安慰剂对照膳食蛋白质补充剂试验。 200 名至少 60 岁的健康女性。将从康涅狄格州中部招募10岁以上的人。将招募自然摄入适度低（但足够）水平的膳食蛋白质（0.6-1 g/kg）的受试者。（大约 30-40% 的 60 岁以上美国女性属于这一群体）。基线测量后，受试者将被随机分配接受安慰剂（麦芽糖糊精）或 40 克蛋白质补充剂，为期 18 个月。该试验的主要结果指标是通过 DEXA 评估的脊柱骨密度。次要结果包括通过 QCT 测量的脊柱和髋部 BMD、矿物质稳态和骨转换的血清测量以及身体机能评估。这些研究将更好地为最佳骨骼健康提供膳食蛋白质建议，如果我们的假设正确，将为与年龄相关的骨质流失提供新的治疗方法。