Table 2.
Effect of Juglans regia L. on Parkinson’s disease, depression, anxiety, mood states, pain, and epilepsy
| Compound | Study design | Doses/Duration | Results | Ref. |
|---|---|---|---|---|
| Parkinson’s disease | ||||
| Walnut extract | in vitro, primary mesencephalic cells in vivo, mice | 0.1 and 1 µg/ml, 24 hr 100 mg/kg, 6 days, PO |
↓ ROS and nitric oxide productions in primary mesencephalic cells - inhibited reduction of striatal dopamine and its metabolites |
(73) |
| Walnut | in vivo, mice | 6% of the diet, 28 days | ↑ dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acid, ATP in the striatum ↑ GSH, GPx amounts in striatum and substantia nigra, mitochondrial complex I activity in substantia nigra ↓ TBARS, SOD, CAT striatum and substantia nigra, MAO-B activity in the striatum |
(71) |
| Depression, anxiety, and mood states | ||||
| Walnut fruit extract | in vivo, rats | 100 and 150 mg/kg, IP | ↓ duration of immobility in the Forced swimming test and tail suspension test | (76) |
| Different extracts of walnut | in vivo, mice | 100, 200 and 400 mg/kg, PO | - ethanol extract of J. regia showed significant dose-dependent antianxiety and antidepressant activity at 200 and 400 mg/kg | (77) |
| Walnut | clinical trial, 64 college students |
60 g, eight weeks | - improve mood in non-depressed, healthy young males ↑ α-linolenic acid and linoleic acid amount in serum |
(78) |
| Pain | ||||
| Aqueous and ethanolic extracts of J. Regia L. leaves | in vivo, mice | aqueous extract: 0.41, 1.64, and 2.87 g/kg, IP Ethanolic extract: 0.292, 1.17, and 2.044 g/kg, IP |
- antinociceptive activity in writhing test - both extracts displayed anti-inflammatory properties |
(39) |
| Methanolic extract of J. regia L. leaf | in vivo, rats | 200 mg/kg, 8 weeks, PO | ↑ antioxidant status in the sciatic nerve ↓ degeneration of the sciatic nerves, caspase-3, COX-2, iNOS expression, lipid peroxidation and nociceptive response, blood sugar, behavioral and structural indices of diabetic neuropathy |
(83) |
| J. regia L. oil and J. regia L. ethyl acetate extract | in vivo, mice | 12.5, 25, and 50 mg/kg, eight days, PO | ↑ serum CAT level ↓ lipid-peroxidation, inflammation, blood glucose, thermal-hyperalgesic and anti-allodynic neuropathic-pain |
(84) |
| Aqueous extract of walnuts | in vivo, rodents | 5 and 10% of the batches | ↓ edema, average abdominal cramps | (85) |
| Epilepsy | ||||
| Walnut kernel | in vivo, rats | 6% of the diet, two months, PO | ↑ seizure threshold ↓ neural death, mortality |
(90) |
| Walnut | in vivo, rats | 1.2 g, two months, PO | - delayed the kindling procedure ↓ electrical and behavioral parameters of kindling |
(91) |
| Walnut kernel extract | in vivo, rats | 100 mg/kg, IP | - diazepam and walnut kernel extract presented a synergic anticonvulsant effect ↑ pentylenetetrazole dose required to trigger the first myoclonic jerk ↓ the severity of seizure grades and the mortality rate |
(92) |
| J. regia L. fruit ethanolic extract | in vivo, mice | 200 and 400 mg/kg, PO | ↑ the onset of myoclonic jerks dose-dependently, GSH and CAT levels in the brain ↓ MDA level in the brain |
(89) |
| Walnut peptide extracts | in vivo, mice | 20 mg/kg, IP | - modulated the benzodiazepine receptors ↑ seizure threshold |
(88) |
ATP: adenosine triphosphate; CAT: catalase; COX-2: cyclooxygenase-2; GPx: glutathione peroxidase; GSH: glutathione; iNOS: inducible nitric oxide synthase; IP: intraperitoneal; MAO-B: monoamine oxidase-B; p.o.: oral; ROS: reactive oxygen species; SOD: superoxide dismutase; TBARS: thiobarbituric acid reactive substances