Berries and Bones: The Effect of Polyphenolic Metabolites From Blueberries on Bone Turnover
试验速览
- 阶段
- 1 期
- 入组人数
- 20
- 试验地点
- 2
- 主要终点
- Ca-41 / Ca ratio in 24-hour urinary excretion to estimate calcium loss from bone
研究概览
简要总结
This study uses a bone labeling calcium tracer methodology to compare the dose-response effect of blueberry consumption on calcium retention and bone loss. Post-menopausal women will receive food or beverage products containing freeze-dried blueberries in the amount equivalent to 0.75 (low), 1.5 (medium), and 3 cups (high) of fresh blueberries per day over a 42-day period. The hypothesis is that the polyphenolics found in blueberries will reduce calcium loss from bones.
详细描述
Participants will be dosed with Ca-41, a rare long-lived radioisotope of calcium. After the equilibration of tracer in the body and its deposition in bones (150 days), subjects will be randomized to one of 6 dose sequences, all of which will begin with a 42-day baseline period. During baseline, 24-hour urine will be collected every 14 days. Following baseline, subjects will enter a 42-day intervention period with one of three doses of blueberries equivalent to 0.75 (low), 1.5 (medium), and 3 cups (high) of blueberries per day. Each dose will be provided in the form of freeze-dried blueberry powder incorporated in 2-4 foods or beverages per day. During the intervention, 24-hour urine will be collected weekly for 6 weeks except week 1. After intervention, subjects will enter a 42-day washout period, during which 24-hour urine will be collected every 3 weeks. The entire study duration will be 444 days for subjects who have not been dosed with Ca-41 previously. In a crossover design, all subjects will complete three 42-day intervention periods corresponding to the three doses of blueberries (low, medium, and high), each followed by a 42-day washout period. The dose-response effect of continuous blueberry consumption over a 42-day period on bone resorption in healthy post-menopausal women will be studied by measuring the loss of Ca-41 in urine by Accelerator Mass Spectrometry.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Prevention
- 盲法
- Single (Outcomes Assessor)
入排标准
- 年龄范围
- 45 Years 至 70 Years（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Female subject is healthy
- •Subject is > 4 years past the onset of natural menopause or total hysterectomy
排除标准
- •History of metabolic bone disease or low trauma fractures;
- •Subject taking osteoporosis treatment drugs or glucocorticoids within 6 months of the beginning of the study;
- •Subjects taking bisphosphonates within 2 years of the beginning of the study;
- •History of cancer, thromboembolisms, clotting disorders, uncontrolled hypertension, abnormal thyroid function, malabsorption syndrome, seizure disorders, or heart attack;
- •BMI > 35 kg/m2;
- •Subjects who will not comply with study interventions ;
- •Subjects who will not stop taking natural product supplements of their own selection.
研究组 & 干预措施
Blueberry baseline
No blueberry products provided as part of the usual dietary intake
干预措施: Blueberry Baseline (Dietary Supplement)
Blueberry Low
One blueberry product per day containing an equivalent of 0.75 cups of fresh blueberries provided as part of usual dietary intake for 42 days
干预措施: Blueberry Low (Dietary Supplement)
Blueberry Medium
Two blueberry products per day containing an equivalent of 1.5 cups of fresh blueberries provided as part of usual dietary intake for 42 days
干预措施: Blueberry Medium (Dietary Supplement)
Blueberry High
Four blueberry products per day containing an equivalent of 3 cups of fresh blueberries provided as part of usual dietary intake for 42 days
干预措施: Blueberry High (Dietary Supplement)
结局指标
主要结局
Ca-41 / Ca ratio in 24-hour urinary excretion to estimate calcium loss from bone
时间窗: From the beginning of baseline (week 0) to the end of the 3rd washout period (week 42)
Urinary Ca-41 excretion will be expressed as Ca-41/Ca ratio, which is unit-less, and converted to a percent change from the baseline value. 24-hour urine will be collected approximately every 2 weeks during baseline (week 0, 2, 4, and 6), weekly (except for week 1) during the low, medium, and high blueberry dose interventions completed in a randomized order (weeks 8-12, 20-24, 32-36) and every 3 weeks during the washout periods (weeks 15, 18, 27, 30, 39, 42). Ca-41/Ca ratios will be measured by Accelerator Mass Spectrometry.
次要结局
- Serum biochemical markers of bone metabolism: RANK ligand(Weeks 0, 6, 12, 18, 24, 30, 36, 42)
- Fasting blood and urine analysis of blueberry polyphenolic metabolites(Weeks 0, 6, 12, 18, 24, 30, 36, 42)
- Serum and urine biochemical markers of bone metabolism: calcium concentration(Weeks 0, 6, 12, 18, 24, 30, 36, 42)
- Serum biochemical markers of bone metabolism: Insulin Dependent Growth Factor-1 (IGF-1)(Weeks 0, 6, 12, 18, 24, 30, 36, 42)
- Serum biochemical markers of bone metabolism: Osteoprotegrin(Weeks 0, 6, 12, 18, 24, 30, 36, 42)
- Serum biochemical markers of bone metabolism: 25(OH) Vitamin D(Weeks 0, 6, 12, 18, 24, 30, 36, 42)
- Serum biochemical markers of bone metabolism: Sclerostin(Weeks 0, 6, 12, 18, 24, 30, 36, 42)
- Urine biochemical markers of bone metabolism: N-terminal telopeptide (NTX)(Weeks 0, 6, 12, 18, 24, 30, 36, 42)
- Serum biochemical markers of bone metabolism: procollagen I intact N-terminal (PINP)(Weeks 0, 6, 12, 18, 24, 30, 36, 42)
研究者
Berdine Martin
Research Scientist - Study Director
Purdue University