Possible Neuroprotective Effects of Crocin Against Motor and Neurochemical Changes in Rotenone Induced Animal Model of Parkinson's Disease

Abstract
Backgropund: Parkinson's Disease (PD) is considered a second most common neurodegenerative disease with slow and irreversible nigrostriatal degeneration with subsequent motor and behavioral deficits. Oxidative stress plays a key role in the pathogenesis of PD. Rotenone is a common pesticide inducing PD by the generation of oxidative stress.
Aim of Study: The aim of this study was to investigate the possible neuroprotective effects of crocin (saffron active compound) on rotenone induced Parkinson-like behaviors.
Material and Methods: 70 male Wister Albino rats were divided into 7 groups (10) per each. (1) Control group (normal saline); (2) Crocin 40mg/Kg; (3) Polyethylene Glycol (PEG) group (vehicle of Levodopa); (4) Rotenone group; (5) Rotenone + crocin 20mg/Kg; (6) Rotenone + crocin 40mg/Kg; (7) Rotenone + Levodopa 10mg/Kg. All agents were injected intraperitoneally once a day for 4 weeks. The neurobehavioral tests include open field, descent latency time in the bar test (seconds), forepaw stride length (cm) and locomotor activity. In serum, the level of 8-hydroxydeoxyguanosine 8-OHdG was estimated. The level of Malondialdehyde (MDA), reduced glutathione (GSH), tumor necrosis factor alpha TNF-a, dopamine and nitrite/nitrate levels were measured in the brain tissue.
Results: Rotenone induced neurobehavioral deficits with elevation of brain MDA, brain TNF-a, Nitrite/nitrate level and serum 8-OHdG and reduction of GSH, brain tissue dopamine. Crocin (20 or 40) improved these neurobehavioral deficits. Crocin (20 or 40) and L-DOPA decreased MDA, serum 8-OHdG, TNF-a and Nitrite/nitrate level and increased GSH and dopamine level. Crocin 40 had achieved potent effect compared with crocin 20.
Conclusion: Rotenone induced Parkinson-like behavior in rats. Crocin achieved a protective effect through reducing lipid peroxidation, anti-inflammatory and reducing DNA damage together with improvement of neurobehavioral deficits.