Relationships between brain-derived neurotrophic factor and immune function during dietary supplement treatment of elderly with Alzheimer's dementia

Abstract

Background and Aim The objective of the present study was to investigate the relationships among pro-brain-derived neurotrophic factor (BDNF) and mature BDNF and immune functioning during aloe polymannose multinutrient complex (APMC) treatment in persons with moderate to severe Alzheimer's dementia (AD). Materials and Methods An open-label trial of 12 months was used to execute the study. Thirty-four adults with AD were enrolled and consumed four teaspoons/day of APMC for 12 months. Subjects were assessed at baseline and 12 months follow-up for proBDNF and BDNF and cytokines, growth factors, T-cell and B-cell subsets, and complete blood count to measure immune functioning. All biomarkers were intercorrelated. Results Several relationships were identified between proBDNF, BDNF, and BDNF/proBDNF ratio and immune function at 12 months, particularly BDNF with vascular endothelial growth factor (VEGF) (r=0.55, P=0.03), epidermal growth factor (EGF) (r=0.74, P=0.001), and CD95+CD3+ (%) (r=-0.64, P=0.03) and proBDNF with VEGF (r=0.64, P=0.02), EGF (r=0.86, P<0.001), and CD16+56+ (%) (r=-0.78, P<0.01). Other correlations were noted for various immune function variables with BDNF, proBDNF, and/or BDNF/proBDNF ratio at baseline and 12 months. Dichotomizing subjects on BDNF above and below 5000 pg/mL revealed additional relationships with platelets and neutrophils. Conclusions The associations between BDNF and proBDNF and various immune markers, such as VEGF, EGF, and CD95+CD3+ ratio, provide insight into the link between neurological function and the immune system. These relationships were even stronger in response to APMC treatment, which lends support to previous findings showing improved immune function after dietary supplementation. Relevance for Patients AD patients have conventional treatment options with limited efficacy for counteracting the deleterious effects of the disease on neurological function. The link between neurological and immune function has been understudied in this population. Overall, our results showed a significant beneficial relationship between immune and neurological function, particularly in response to 12 months of treatment with an all-natural polysaccharide-based dietary supplement that is a known immunomodulator. Thus, the use of this dietary supplement may benefit these patients by simultaneously improving immune and neurological function.