Response of Gut Microbiota and Cardiometabolic Biomarkers to Consumption of Walnuts
试验速览
- 阶段
- 不适用
- 状态
- 撤回
- 试验地点
- 2
- 主要终点
- Assessing the influence of walnuts on the fecal metagenome
研究概览
简要总结
The researchers will investigate blood and fecal responses in qualified study participants after eating walnuts for 4 weeks compared to not eating walnuts for 4 weeks. The two dietary interventions will be separated by a 4 week washout period. The order of diets will be random; study participants will complete both interventions. Dietary modifications will be part of the study protocol.
详细描述
The researchers hypothesize that walnut consumption will induce changes in fecal metagenome, identifiable walnut-derived bioactives (urolithins) and other microbial-derived products (short-chain fatty acids and secondary bile acids). The researchers hypothesize that walnut consumption will result in improvements to blood lipid profiles, including decreased total and LDL-cholesterol; increased HDL-related cholesterol efflux capacity and antioxidant protection; and decreased inflammatory biomarkers relative to control diet. The researchers hypothesize changes in cardiometabolic health biomarkers will be correlated with food bioactive metabolites and/or fecal metagenome. Pathway analysis will identify metabolic pathways differentially regulated by walnut-derived bioactives and walnut-responsive microbial genes.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Single (Participant)
入排标准
- 年龄范围
- 20 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Generally healthy men and women between 20-65 years of age and BMI range of 20.0-34.9 kg/m2 will be recruited from the Davis - Sacramento metropolitan area. Enrolled subjects must be willing to consume 2 ounces (approximately 1/2 cup) of walnuts daily and modify their diet to avoid eating walnuts and other nuts, and foods or beverages high in polyphenols (a list will be provided) during study enrollment . Adults unable to consent, individuals who are not yet adults (infants, children, teenagers), pregnant or lactating women, women planning to become pregnant in the next four months and prisoners will be specifically excluded. Screening will take place by phone interview and through in-person screening and consent, including anthropometric and biochemical assessments and health history questionnaires.
排除标准
- •Allergy to walnuts or other nuts
- •Eating more than 25 grams of fiber per day, assessed by the Block Dietary-Fruit-Vegetable-Fiber Screener©
- •Taking medications or supplements known to affect metabolism or gut microbiota composition (i.e. Metformin, statins, antibiotics within the past 3 months, fiber supplements, probiotics, and others)
- •Documented chronic diseases including diabetes, renal or liver disease, metabolic syndrome, active cancer, MI or stroke, history of gastric bypass or GI disease (e.g. Crohn's Disease, Irritable Bowel Disease, diverticulosis/diverticulitis,etc)
- •Smoker or living with a smoker, including vaporizer and/or electronic cigarettes.
- •Illicit drug use, cannabis usage, or consuming >1 alcoholic drink/day
- •Extreme dietary or exercise patterns; vegan diet.
- •Recent weight fluctuations (>10% in the last 6 months)
- •Taking prescription lipid medications or supplements that may affect lipoprotein metabolism (i.e. >1 g of fish oil/day, antioxidant supplements)
- •Taking exogenous hormones (e.g. hormonal birth control)
- •Poor venous access
- •Unwillingness to comply with study protocols
结局指标
主要结局
Assessing the influence of walnuts on the fecal metagenome
时间窗: Through study completion, an average of 12 weeks
Changes in fecal metagenomics will be assessed via Illumina sequencing
Assessing the influence of walnuts on fecal secondary bile acids
时间窗: Through study completion, an average of 12 weeks
Fecal secondary bile acids will be measured by LC-QTOF/MS
Assessing the influence of walnuts on fecal short-chain fatty acids
时间窗: Through study completion, an average of 12 weeks
Short-chain fatty acids in fecal matter will be measured by LC-MS/MS
Urolithins measured in plasma by UPLC/MS
时间窗: Through study completion, an average of 12 weeks
Measure for changes in the levels of urolithins in separated plasma; measured in units of ug/uL. Blood will be assessed at each of the 4 study visits.
Fecal calprotectin will be measured by ELISA
时间窗: Through study completion, an average of 12 weeks
Measure for changes in the levels of calprotectin in collected fecal matter; measured in units of ug/g. Feces will be assessed at each of the 4 study visits.
次要结局
- Assessing the influence of walnuts on blood lipid measurements(Through study completion, an average of 12 weeks)
- Measure for changes in weight(Through study completion, an average of 12 weeks)
- Assessing the influence of walnuts on paraoxonase-1 (PON-1) activity(Through study completion, an average of 12 weeks)
- Assessing the influence of walnuts on cholesterol ester transfer protein activity (CETP)(Through study completion, an average of 12 weeks)
- Assessing the influence of walnuts on SAA will be measured in blood(Through study completion, an average of 12 weeks)
- Dietary record analysis(Through study completion, an average of 12 weeks)
- Measure for changes in blood pressure(Through study completion, an average of 12 weeks)
- Assessing the influence of walnuts on hsCRP will be measured in blood(Through study completion, an average of 12 weeks)
- Assessing the influence of walnuts on circulating cytokines(Through study completion, an average of 12 weeks)
- Assessing the influence of walnuts on peripheral blood mononuclear cells (PBMC) using ex vivo stimulation assays(Through study completion, an average of 12 weeks)
- Anthropometric measurements(Through study completion, an average of 12 weeks)