A Pilot Study of Dietary Taxifolin/Dihydroquercetin and Ergothioneine and Immune Biomarkers in Healthy Volunteers
试验速览
- 阶段
- 不适用
- 状态
- 进行中（未招募）
- 入组人数
- 90
- 试验地点
- 2
- 主要终点
- Phagocytosis activity by granulocytes ex vivo
研究概览
简要总结
The complexities of the immune system make measuring the impact of dietary interventions upon its function challenging. The immune system is highly responsive to environmental influences, including the diet. An individual's diet provides the energy required to mount a strong and protective immune response, the building blocks required for synthesis of immune mediators such as antibodies and cytokines, and can also indirectly affect immune function via changes in the gut microbiome. Immune function varies across the lifecourse, with a well understood decline in immune function with age, resulting in impaired vaccination responses and an increased risk of infections and of severe complications and mortality arising from common communicable diseases such as influenza. This impaired immunity with ageing is known as immunosenescence and this affects both innate and acquired arms of the immune system.
详细描述
Expert guidance is available to inform the design of human nutrition trials to ensure they include the most relevant immunological outcomes (Albers, 2013). In this study, ex vivo phagocytosis and oxidative burst of immune cells will be the primary outcome, supported by other ex vivo immune measures of high clinical relevance including functional assessment of cytokine production and expression of activation markers.
Human nutritional trials frequently omit to monitor the degree of immunosenescence in participants, even amongst studies conducted amongst older adults. For example, a recent review of pre- and probiotic trials which assessed immune responses in older adults identified that only two of thirty-six studies assessed any marker of immunosenescence (Childs & Calder, 2017).
Taxifolin/DHQ is a naturally occurring polyphenol found in apples, onions and other fruits and bark extracts. Ergothioneine is an amino acid found in mushrooms, oats and some bean varieties. We hypothesise that Taxifolin/DHQ and/or Ergothioneine will alter immune function via their established antioxidant effects, and that the effects observed will vary between older adults relative to their degree of immunosenescence.
Though current dietary guidelines advise consumption of 5 portions of fruits and vegetables per day, recent surveys reveal that fewer than 30% of adults achieve this. Antioxidants found within fruits and vegetables are understood to be one of the important aspects by which our diet can influence health. It is important to investigate the effects of such antioxidants through well designed and conducted human trials.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
盲法说明
Alphabetically labelled treatments, with de-blinding envelope held by an independent researcher at the University of Southampton.
入排标准
- 年龄范围
- 50 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •age 50-65yr
- •BMI 18.5-30kg/m2
- •Willing to avoid consumption of foods rich in Taxifolin/DHQ and Ergothioneine during the study period
- •Willing to avoid taking any other food supplements or high doses of vitamins during the study period
- •Able to provide written informed consent.
排除标准
- •Use of prescription medication which may influence immune function, such as anti-inflammatory or immunosuppressant medication
- •Diabetes requiring any medication
- •Liver cirrhosis
- •A history of drug or alcohol misuse
- •Asplenia or other acquired or congenital immunodeficiencies
- •Any autoimmune disease including connective tissue diseases
- •Malignancy
- •Laboratory confirmed SARS-CoV-2 infection within last 3 months
- •self-reported symptoms of acute or recent infection (including use of antibiotics within the last 3 months)
研究组 & 干预措施
Control
One capsule in the morning for 8 weeks.
干预措施: Control (Dietary Supplement)
Ergothioneine
80mg/day Ergothioneine. One capsule in the morning for 8 weeks.
干预措施: Ergothioneine (Dietary Supplement)
Taxifolin/Dihydroquercetin
250mg/day Taxifolin (also known as Dihydroquercetin). One capsule in the morning for 8 weeks.
干预措施: Taxifolin (Dietary Supplement)
结局指标
主要结局
Phagocytosis activity by granulocytes ex vivo
时间窗: 8 weeks post intervention
Mean fluorescence intensity per cell will be assessed by flow cytometry.
次要结局
- Phagocytosis activity by monocytes ex vivo(4 weeks, 8 weeks, 3 months post intervention)
- Cytokine production by cryopreserved peripheral blood mononuclear cells in response to influenza or coronavirus vaccine products(4 weeks, 8 weeks)
- Metabolomic analysis of urine samples(4 weeks, 8 weeks, 3 months post intervention)
- Duration of self-reported illness.(4 weeks, 8 weeks, 3 months post intervention)
- Percentage phagocytosis by monocytes ex vivo(4 weeks, 8 weeks, 3 months post intervention)
- Percentage phagocytosis by granulocytes ex vivo(4 weeks, 8 weeks, 3 months post intervention)
- Percentage oxidative burst by granulocytes ex vivo(4 weeks, 8 weeks, 3 months post intervention)
- Oxidative burst activity by granulocytes ex vivo(4 weeks, 8 weeks, 3 months post intervention)
- Frequencies of naive T cells(8 weeks)
- Frequencies of memory T cells(8 weeks)
- Urinary isoprostanes(4 weeks, 8 weeks, 3 months post intervention)
- Cytokine production by cryopreserved peripheral blood mononuclear cells in response to lipopolyssaccharide(4 weeks, 8 weeks)
- Incidence of self-reported seasonal cold, coronavirus and influenza-like illness.(4 weeks, 8 weeks, 3 months post intervention)
- Phagocytosis activity by granulocytes ex vivo(4 weeks, 3 months post intervention)
- Percentage oxidative burst by monocytes ex vivo(4 weeks, 8 weeks, 3 months post intervention)
- Oxidative burst activity by monocytes ex vivo(4 weeks, 8 weeks, 3 months post intervention)
- Faecal microbiome analysis(4 weeks, 8 weeks, 3 months post intervention)
- CD57 expression upon T cells.(8 weeks)
- CD28 expression upon T cells.(8 weeks)
- Plasma lipid peroxides(8 weeks)
- Plasma isoprostanes(4 weeks, 8 weeks, 3 months post intervention)
- Metabolomic analysis of serum samples(4 weeks, 8 weeks, 3 months post intervention)
- Severity of self-reported illness.(4 weeks, 8 weeks, 3 months post intervention)
- Self-reported medication use.(4 weeks, 8 weeks, 3 months post intervention)