Effect of Blueberry Supplementation on Alzheimer's Biomarkers

The purpose of this study is to study the effects of blueberries on neuronal, glial, and pathology blood biomarkers in Mild Cognitive Impairment (MCI) and to estimate sample size for future confirmatory studies. The blood biomarkers to be measured are Neurofilament light (NfL), glial fibrillary acidic protein (GFAP), Aß40, Aß42, p-tau181, and cytokines, using an ultra-sensitive state-of-the-art immunoassay.

After determining subject eligibility and after subjects have abstained from consuming all berry fruits (including red wine) for 2 weeks, subjects will have blood drawn for biomarkers and will then will undergo 12 weeks of blueberry supplementation in the form of 18 grams lyophilized blueberry powder mixed with water and taken twice daily with meals. All subjects will be asked to abstain from berry fruits (including red wine) for the duration of the 12 week trial. Subjects will receive telephone calls at 4 and 8 weeks to check compliance as well as concomitant medications and adverse events and then all subjects will return at 12 weeks for a repeat biomarker blood draw. Plasma NfL, GFAP, Aβ40, Aβ42, p-tau181, and cytokine biomarker assays will be done using the Quanterix SR-X instrument, a new, state-of-the-art digital immunoassay platform employing Simoa technology, which enables the detection and quantification of biomarkers previously difficult or impossible to measure.

All participants will receive 18 grams lyophilized blueberry supplement mixed with water twice daily for 12 weeks.

Inclusion Criteria: 55 to 85 years old inclusive Meets criteria for amnestic Mild Cognitive Impairment defined by education adjusted performance on the Wechsler Memory Scale (WMS) III Logical Memory delayed recall score and clinical evaluation. Medically stable Exclusion Criteria: Dementia Significant confounding active neurological/psychiatric disease Participation in an experimental investigational drug trial in the past 30 days Unwilling to restrict consumption of anthocyanin-rich foods Inability to complete cognitive testing (e.g. significant visual or hearing impairment) Allergy or intolerance to blueberries Significant gastrointestinal disorders or surgery that influences digestion and absorption Presence of unstable, acutely symptomatic, or life-limiting illness Women of childbearing potential

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