Table 2.
All reviewed studies investigating the effects of DR in PD. N/A: relevant data not reported; n/s: relevant data not significant; MPTP: 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine;.SN: substantia nigra; GDNF glial cell line-derived neurotrophic factor; 6-OHDA: oxidopamine or 6-hydroxydopamine; ANS: autonomic nervous system; p-AMPK: phosphorylated AMP-activated protein kinase; ACC acetyl-CoA carboxylase; IBA-1: ionized calcium-binding adapter molecule 1; GFAP: Glial Fibrillary Acidic Protein; BDNF: brain-derived neurotrophic factor; HKD: hyper ketogenic diet; LFHC low fat high carbohydrate diet.
| 1 Parkinson’s Disease Animal Studies | ||||||
|---|---|---|---|---|---|---|
| Model Organism (Drug) | Age & Sex | Dietary Interventions | Motor Function & Neurogenesis | Brain Pathology | Biomarkers | Reference |
| Sprague–Dawley rats (6-OHDA) | male | ADF for 2 or 8 weeks before 6-OHDA injections | N/A | n/s | N/A | Armentero et al. 2008 [100] |
| C57Bl/6 mice (MPTP) | 4 months, male | ADF for 3 months before MPTP injections | ↑ motor co-ordination | ↑ SN dopaminergic neurons, ↓ SN neuronal damage | N/A | Duan et al. 1999 [95] |
| THY1-SNCA*A53T mice | 12 weeks, male | ADF for 12 weeks | ↓ ANS dysfunction, ↑ motor co-ordination | ↓ α-synuclein in the brain stem | N/A | Griffioen et al. 2013 [102] |
| ghrelin WT/KO mice (MPTP) | 8 to 10 weeks, male | 30% CR for 27 days | n/s | ↑ SN dopaminergic neurons (ghrelin WT), ↑ striatal dopamine (ghrelin WT) | ↑ p-AMPK, ↑ ACC | Bayliss et al. 2016 [96] |
| ghrelin receptor WT/KO mice (LAC) | 3–4 months and 18–22 months, male | 30% CR regimen for 28 days. LAC injections after 21 days on 30% CR | N/A | ↑ SN dopaminergic neurons, ↑ striatal dopamine | N/A | Coppens et al. 2017 [97] |
| C57BL/6J (Rotenone) | 8 weeks, male | ADF for 28 days | ↓ motor-co-ordination | ↓ SN dopaminergic neurons, ↓ striatal dopamine, ↑ α-synuclein in the SN | ↓ IGF-1 (IF); ↑ LPC & SM (Rotenone + IF) | Tatulli et al. 2018 [101] |
| C57Bl/6 mice (MPTP) | 7 weeks, male | 2 FMD cycles before and 1 FMD cycle after MPTP | ↑ motor co-ordination | ↑ SN dopaminergic neurons, ↑ striatal dopamine and its metabolites | ↓ pro-inflammatory cytokines, ↓ IBA-1, ↓ GFAP, ↑ BDNF | Zhou et al. 2019 [104] |
| Rhesus monkeys (MPTP) | 9–17 years, male | 30% CR for 6 months before an MPTP injection | ↑ motor co-ordination | ↑ SN dopaminergic neurons, ↑ striatal dopamine and its metabolites | ↑ GDNF | Maswood et al. 2004 [106] |
| 2 Parkinson ’s Disease Human Studies | ||||||
| Patient Population | Age & Sex | Dietary Interventions | Clinical Findings | Reference | ||
| Overweight or obese adults with PD (prospective study) | (mean: 61) male & female | HKD (n = 5) for 28 days | n/s | Vanitallie et al. 2005 [109] | ||
| Adults with PD | (mean: 63) male & female | LFHC (n = 20/23) or KD (n = 18/24) for 8 weeks | ↑ motor and non-motor PD symptoms | Phillips et al. 2018 [110] | ||