Brain Aging

This proposal will test the hypothesis that AKG supplementation will improve NGVC responses and cognitive performance in older adults. We will also test the hypothesis that these effects are mediated by a decrease in age-related oxidative stress within NGVU cells.

This randomized placebo-controlled clinical study, called the LpD3.5 Intervention Study in Older Adults (LISA), aims to evaluate whether a heat-inactivated postbiotic of human origin (LpD3.5) can serve as a non-pharmacological intervention to reduce gut permeability and inflammation in older adults with mild cognitive impairment (MCI). The study will assess the effects of LpD3.5 supplementation on markers associated with gut health, inflammation, microbiome composition, and cognitive function. Participants aged 60 years or older with clinically diagnosed MCI will receive either LpD3.5 capsules or placebo capsules for 60 days, followed by a 30-day follow-up period. Biological samples and clinical assessments will be collected to evaluate changes in gut permeability, inflammatory markers, microbiome characteristics, and cognitive outcomes. The findings from this study may provide insight into the potential role of postbiotics as a dietary intervention to improve gut health and related outcomes in older adults with MCI.

The goal of this pilot clinical trial is to test whether transcranial photobiomodulation (tPBM), a non-invasive brain stimulation technique using near-infrared light, can improve brain blood flow regulation (neurovascular coupling) and cognitive function in older adults. The main questions it aims to answer are: * Does tPBM enhance neurovascular coupling responses during memory and finger tapping tasks? * Are these improvements linked to better cognitive performance and lower levels of brain inflammation and oxidative stress? Researchers will compare an active tPBM treatment arm to a sham treatment arm to see if tPBM leads to measurable improvements in brain activity and cognitive function compared to no active stimulation. Participants will: * Receive either active tPBM or sham stimulation sessions for 4 weeks, every other day using a portable intervention device. * Complete questionnaires and an iPAD-based cognitive testing protocol * Complete memory and motor tasks while their brain activity is measured using non-invasive techniques: simultaneous functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG), transcranial doppler (TCD) flowmetry. * Retinal vessel reactivity will be measured during flickering light stimulus using a special camera (dynamic vessel analysis, DVA). * Provide blood samples to test for biomarkers of inflammation, oxidative stress and brain cell damage.

This randomized, double-blind, placebo-controlled pilot trial will evaluate the effects of alpha-linolenic acid (ALA) supplementation on cognitive function, blood-brain barrier integrity, and brain vascular health in older adults with mild cognitive impairment and APOE4 genotype. By targeting the endogenous synthesis of docosahexaenoic acid (DHA) through ALA supplementation, the investigators aim to overcome the limitations of direct DHA supplementation, particularly in APOE4 carriers who exhibit low brain DHA levels and impaired blood-brain barrier function. This innovative approach offers a safe, cost-effective, and easily implementable therapeutic strategy for older adults at high risk for Alzheimer's dementia, especially APOE4 carriers, addressing a critical need given the limited cognitive benefits and significant adverse events of current amyloid-clearing drugs in this population.

We recruit community-dwelling older adults aged 50 and above for a 6-month intervention. Participants are divided into three groups: Placebo Group, Low-Dose Group ( 6 mg/d Haematococcus pluvialis Astaxanthin), High-Dose Group (12 mg/d Haematococcus pluvialis Astaxanthin). Peripheral blood samples and Other tests are collected at baseline, 3 months, and 6 months to measure mitochondrial function and oxidative stress levels. Assessments include: 1.Cognitive \& Neurophysiological Assessment: Using the MoCA (Montreal Cognitive Assessmentscale) and ERP (specifically P300) monitoring. 2.Brain Imaging: MRI (Magnetic resonance imaging) is used to analyze changes in brain function. 3.Metabolomics: A series of laboratory techniques are used to analyze routine metabolic indices, plasma astaxanthin, mitochondrial function, oxidative stress markers, and cognition-related neurobiomarkers.

The goal of this clinical trial is to determine if adding avocados to the diet of impacts cognition in 70 older adults, age 65-85, without dementia. We will test for change in functional MRI, cognitive performance, and brain blood flow. Intervention group participants will be asked to consume 1 avocado per day for 12 weeks. Participants in the control group will be asked to continue their normal intake for 12 weeks. Throughout the study, participants will be asked to perform cognitive tests, MRI, blood tests, and questionnaires.