Neuroprotective effect of the methanolic extract of Hibiscus asper leaves in 6-hydroxydopamine-lesioned rat model of Parkinson's disease

Antioxidant Activity of Oral Administration of Rosmarinus Officinalis Leaves Extract on Rat's Hippocampus which Exposed to 6-Hydroxydopamine

“…Antioxidants are expected to have a major impact on the treatment of PD. The natural occurrence of antiparkinsonian drugs in plants: anticholinergics in Datura stramonium, levodopa in Mucuna pruriens and Vicia faba, dopamine agonist activity in Claviceps purpura, and MAO inhibitor activity in Banisteria caapi and Ginkgo biloba leaves extract are known (Hritcu et al 2011;Hwang et al 2011;Song et al 2012;Song SS et al 2012;). Green and black tea extracts attenuated neuronal apoptosis induced by 6-OHDA (Chaturvedi et al 2006;Guo et al 2007;Bitu Pinto et al 2015).…”

“…This model represents a good model of the early phase of PD because of its mild motor impairment and cognitive deficits and ideal to see the suitability of neuroprotective agents (Hritcu et al 2011). Importantly, in recent years, it was indicated that non motor deficits became an important part of patient management (Whittington et al 2006, Hanna-Pladdy et al 2013.…”

“…Accumulation of iron in substantia nigra contributes to the cell death by enhancing lipid peroxidation, as judged by raised levels of both malondialdehyde and lipid hydroperoxides (Hauser et al 2013;Ward et al 2015). But the hippocampus is the most vulnerable area to oxidative stress, it was demonstrated that an early event in the course of dopamine depletion following 6-OHDA administration is the generation of oxidative stress in the hippocampus and it caused memory impairment (Hritcu et al 2011;Sriraksa et al 2012;Zaltieri et al 2015). The post-mortem studies from PD patients suggested the involvement of an excess formation of free radicals and the onset of oxidative stress in the disease progression (Ren et al 2009).…”

“…The presence of neuromelanin in dopaminergic cells and autoxidation of dopamine responsible for the high basal levels of oxidative stress in substantia nigra (Munoz et al 2012). Because of the dentate gyrus of the hippocampus receives dopaminergic projections from the ventral tegmental area and substantia nigra, these connections might be affected by oxidative stress (Hritcu et al 2011;Sriraksa et al2012). The sensitivity of the mesohippocampal pathway to selective toxins also demonstrated its vulnerability to free radical attack.…”

“…Our previous reports demonstrated that rats treated with 6-OHDA suffered impairments in memory processes, which are associated with alterations in the brain antioxidant status and lipid peroxidation (Ciobica et al 2012). Consequently, several reports suggested that many plant extracts have neuroprotective activity against 6-OHDA-induced toxicity through antioxidant and antiapoptotic activities in PD models (Hritcu et al 2011;Hwang et al 2011). Oxidative stress results from an imbalance between the cellular production of ROS and antioxidant mechanisms that remove them, although several antioxidant molecules in the brain such as superoxide dismutase (SOD), glutathione peroxidase and ascorbate can remove the ROS (Brieger et al 2012).…”