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1. The Neurocognitive Effects of Bacopa monnieri and Cognitive Training on Markers of Brain Microstructure in Healthy Older Adults

Author

Grace M. McPhee, Luke A. Downey, Keith A. Wesnes, and Con Stough

Subjects
Bacopa monnieri, Brahmi, cognitive training, cognitive aging, brain microstructure, diffusion weighted imaging, Neurosciences. Biological psychiatry. Neuropsychiatry, RC321-571
Abstract

Bacopa monnieri (BM) is a herbal supplement that increases signaling molecules implicated in synaptogenesis. Combined with cognitive stimulation, it may be a viable supplement to enhance long-term potentiation (LTP) and improve cognitive health in older adults. This randomized, double-blind, placebo-controlled trial asked 28 healthy adults aged over 55 years to complete cognitive training (CT) 3 hours weekly for 12 weeks. Fifteen consumed a standardized extract of BM and 13 consumed a placebo daily. Cognitive tasks, life-satisfaction, memory complaints and mood were assessed, and bloods analyzed for serum brain-derived neurotrophic factor (BDNF) before and after 12-weeks of the intervention. Diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) in gray (GM) and white matter (WM) were also analyzed. Results demonstrated slower reaction time in an image discrimination task in the BM group and faster reaction time in a spatial working memory task (SWM-O RT) in the placebo group. Mean accuracy was higher in the BM group for these tasks, suggesting a change in the speed accuracy trade-off. Exploratory neuroimaging analysis showed increased WM mean diffusivity (MD) and GM dispersion of neurites (orientation dispersion index, ODI) and decreased WM fractional anisotropy (FA) and GM neurite density (ND) in the BM group. No other outcomes reached statistical significance. An increase in ODI with a decrease in MD and ND in the BM group may indicate an increase in network complexity (through higher dendritic branching) accompanied by dendritic pruning to enhance network efficiency. These neuroimaging outcomes conflict with the behavioral results, which showed poorer reaction time in the BM group. Given the exploratory outcomes and inconsistent findings between the behavioral and neuroimaging data, a larger study is needed to confirm the synaptogenic mechanisms of BM.

Published
2021
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2. The Effect of a High-Dose Vitamin B Multivitamin Supplement on the Relationship between Brain Metabolism and Blood Biomarkers of Oxidative Stress: A Randomized Control Trial

Author

Talitha C. Ford, Grace M. McPhee, Con Stough, Chris Oliver, Tamara Simpson, and Luke A. Downey

Subjects
0301 basic medicine, Male, Homocysteine, medicine.disease_cause, Antioxidants, chemistry.chemical_compound, 0302 clinical medicine, Cognition, Blood plasma, Medicine, Choline, oxidative stress, posterior cingulate cortex, Nutrition and Dietetics, Brain, Middle Aged, 3. Good health, Vitamin B Complex, Female, Multivitamin, lcsh:Nutrition. Foods and food supply, Adult, medicine.medical_specialty, 1H-MRS, B vitamins, lcsh:TX341-641, Creatine, Article, 03 medical and health sciences, multivitamin, Double-Blind Method, Internal medicine, Humans, Vitamin B12, Aged, Inflammation, NAA, Aspartic Acid, business.industry, 030104 developmental biology, Endocrinology, chemistry, Dietary Supplements, business, Cognition Disorders, 030217 neurology & neurosurgery, Oxidative stress, Biomarkers, Food Science
Abstract

A diet rich in B-group vitamins is essential for optimal body and brain function, and insufficient amounts of such vitamins have been associated with higher levels of neural inflammation and oxidative stress, as marked by increased blood plasma homocysteine. Neural biomarkers of oxidative stress quantified through proton magnetic spectroscopy (1H-MRS) are not well understood, and the relationship between such neural and blood biomarkers is seldom studied. The current study addresses this gap by investigating the direct effect of 6-month high-dose B-group vitamin supplementation on neural and blood biomarkers of metabolism. Using a randomized, double-blind, placebo-controlled design, 32 healthy adults (20 female, 12 male) aged 30&ndash, 65 years underwent blood tests (vitamin B6, vitamin B12, folate, and homocysteine levels) and 1H-MRS of the posterior cingulate cortex (PCC) and dorsolateral prefrontal cortex (DLPFC) before and after supplementation. Results confirmed the supplement was effective in increasing vitamin B6 and vitamin B12 levels and reducing homocysteine, whereas there was no change in folate levels. There were significant relationships between vitamin B6 and N-acetylaspartate (NAA), choline, and creatine, as well as between vitamin B12 and creatine (ps &lt, 0.05), whereas NAA in the PCC increased, albeit not significantly (p &gt, 0.05). Together these data provide preliminary evidence for the efficacy of high-dose B-group supplementation in reducing oxidative stress and inflammation through increasing oxidative metabolism. It may also promote myelination, cellular metabolism, and energy storage.

Published
2018

3. Reducing occupational stress with a B-vitamin focussed intervention: a randomized clinical trial: study protocol

Author

Grace M. McPhee, Justine Lomas, Stephen P Myers, Tamara Simpson, Chris Oliver, Clare Billings, Con Stough, and Luke A. Downey

Subjects
Male, Magnetic Resonance Spectroscopy, Cost-Benefit Analysis, Psychological intervention, Medicine (miscellaneous), Burnout, law.invention, Placebos, Cognition, Randomized controlled trial, law, Surveys and Questionnaires, Medicine, Homocysteine, Nutrition and Dietetics, fMRI, Middle Aged, 16. Peace & justice, Magnetic Resonance Imaging, 3. Good health, Occupational Diseases, Treatment Outcome, Vitamin B Complex, Workforce, Absenteeism, Female, MRI, Adult, MRS, medicine.medical_specialty, B vitamins, Stress, Double-Blind Method, Intervention (counseling), Environmental health, Genetics, Humans, Aged, Work-related stress, business.industry, Research, Australia, Occupational stress, Diet, Affect, Dietary Supplements, Physical therapy, business, Stress, Psychological
Abstract

Background Workplace stress in Australia and other western countries has been steadily increasing over the past decade. It can be observed not only in terms of increased compensation claims but also costs due to absenteeism, loss of productivity at work and reduced psychological and physiological health and well-being. Given the cost and pervasive effects of stress in the modern workforce, time efficient and cost-effective interventions capable of reducing occupational stress (or strain) and burnout are urgently required for the improved well-being of stressed employees. One intervention gaining scientific traction is supplementation with nutritional interventions, particularly the B group vitamins. Methods This study was developed to examine the effects of B group vitamins on workplace stress and mood variables with a sample of full-time employed older adults who subjectively report feeling stressed. The study is a randomized, double-blind, placebo-controlled, parallel-groups clinical trial where 200 (N = 100/group) participants will be randomized to receive Blackmores® Executive B Stress Formula or placebo daily for a period of 6 months. Participants will be tested at baseline and 6 months post-randomization on workplace stress, cognitive, personality and mood measures, cardiovascular (brachial and aortic systolic and diastolic blood pressures as well as arterial stiffness), biochemical (assays to measure inflammation and safety) as well as genetic assessments (to assess stress processing) and neuroimaging measures (to investigate in vivo mechanisms of action of B vitamins). In addition to this pre- and post- supplementation testing, participants will also complete a battery of self-report questionnaires online to assess their stress and mood once a month for the duration of the study. The primary aim of the study is to investigate the effects of B vitamin supplementation on work related stress. The secondary aims are to explore the mechanisms underpinning any changes in mood or workplace stress due to the B vitamin intervention by examining relationships between cognitive, biological, neuroimaging and cardiovascular variables over 6 months. A subset of 40 participants (N = 20/group) will undergo neuroimaging at baseline and at 6 months using functional magnetic resonance imaging (fMRI) and magnetic resonance spectroscopy (MRS) in order to further explore in vivo mechanisms of action of B vitamins. Trial registration Australia and New Zealand Clinical Trials Register (ANZCTR):ACTRN12613000294752

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