The use of dietary supplements and perceived quality of life in patients with Parkinson's disease.

Patients with chronic illnesses represent a segment of adults among whom intake of dietary supplements is particularly prevalent. Previous studies have shown that intake of different dietary supplements to improve perceived quality of life of patients with or without objective improvement in other physiological parameters. We recently conducted an open-label trial of blackcurrant anthocyanin supplementation in patients with PD. Participants were administered the PDQ-39 (a 39-item quality-of-life instrument) before and after blackcurrant supplementation. Patients scored significantly lower in the emotional well-being domain (i.e., reported better emotional quality of life) after blackcurrant anthocyanin supplementation (t9 = -3.97, p = 0.008). It is plausible that the attention our participants received during the study period could have positively affected their mood. It is also possible that a placebo effect of the fruit-derived supplement-often viewed as a healthy alternative to medicines-was in play. Our findings reiterate the high prevalence of supplement intake among PD patients, and the importance of being attentive when caring for patients whether they take supplements or not.

Supplementation of Blackcurrant Anthocyanins Increased Cyclic Glycine-Proline in the Cerebrospinal Fluid of Parkinson Patients: Potential Treatment to Improve Insulin-Like Growth Factor-1 Function.

BACKGROUND: Insulin-like growth factor-1 (IGF-1) function is impaired in Parkinson disease. Cyclic glycine-proline (cGP), a metabolite of IGF-1, is neuroprotective through improving IGF-1 function. Parkinson disease patients score lower on Hospital-associated Anxiety and Depression Scale after supplementing blackcurrant anthocyanins (BCA), which may be associated with IGF-1 function. We evaluated the changes of cGP and IGF-1 before and after the supplementation. METHODS: Plasma and cerebrospinal fluid (CSF) were collected from 11 male patients before and after 28 day supplementation of BCA. The concentrations of IGF-1, IGF binding protein (IGFBP)-3, and cGP were measured using ELISA and HPLC-MS assays. The presence of cGP in the BCA was evaluated. RESULTS: cGP presented in the BCA. BCA supplementation increased the concentration of cGP (p < 0.01), but not IGF-1 and IGFBP-3 in the CSF. CSF concentration of cGP was correlated with plasma concentration of cGP (R = 0.68, p = 0.01) and cGP/IGF-1 molar ratio (R = 0.66, p = 0.01). The CSF/plasma ratio was high in cGP and low in IGF-1 and IGFBP-3. CONCLUSION: cGP is a natural nutrient to the BCA. The increased CSF cGP in Parkinson disease patients may result from the central uptake of plasma cGP. Given neurotrophic function, oral availability, and effective central uptake of cGP, the BCA has the potential to be developed to treat neurological conditions with IGF-1 deficiency.