Neuroprotective Efficacy of <i>Maytenus emarginata</i> (Wild.) Ding Hou Against Paraquat Induced Oxidative Stress and Neurotoxicity in Drosophila Model System

Abstract

An investigation has been made to find out the disease altering therapies against a somber ailment called ‘early aging’ which is due to the formation of free radicals during the natural course of metabolism, also act randomly and indiscriminately to damage the cell components. On the contrary, the natural antioxidants in dietetic practice can diminish these free radicals which can perturb further, the progression of these age-related neurodegenerative disorders such as Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD) followed by Canine Cognitive dysfunction. As a consequence, a tribal medicinal plant; <i>Maytenus emarginata</i> (Wild.) Ding Hou (family-‘<i>Celastraceae</i>’) was identified which is commonly called ‘Thorny staff tree’ a potent ethno-medicinal plant drug was opted during the interactions held with tribal healers. This candidate plant drug is being practiced as memory-enhancing factor in their tribal medicinal system at Biligirirangana Hills (B. R. Hills) of Chamarajanagara district, India. Hence, the biological screening with Methanol extract of <i>Maytenus emarginata</i> (MEM) was attempted initially for Physico-chemical, Phyto-chemical properties followed by <i>in vitro</i>, <i>in vivo</i> antioxidant and neuroprotective activities using <i>Drosophila melanogaster</i> (Oeragon K) strain adult male flies. In the result, the extract of M exhibited concentration dependent DPPH scavenging activity. The oxidative stress markers employed to access in vivo antioxidant property of M included lipid peroxidation products malondialdehyde (MDA) and hydroperoxide (HP), reduced glutathione (GSH). The modulatory effect of M on superoxide dismutase (SOD) and catalase (CAT) was also determined. The oxidative stress was induced by using paraquat at 15 mM. The concentration of extract for studies was fixed based on LC₅₀ values. There was a significant demolition in the levels of MDA and HP in co-exposure of M with Par treated flies homogenate. The level of SOD and CAT was brought to near basal level in the homogenate of flies co-exposed with M and Par. In negative geotaxis assay it was found that M was able to rescue the flies significantly from deteriorating locomotors dysfunctions. The M extract exhibited significant modulatory activity in regulating oxidative stress markers and antioxidants in the fly homogenate. The extract M also exhibited significant antibacterial property against tested microbial strains. Therefore, the findings point out that, MEM plant drug was found to be most promising in its efficacy which may act as compelling antioxidant agent that can intensify the locomotors functions. Thus, the MEM plant drug therapy can regulate the occurrence of CCD, AD, PD and HD and the normal condition may be reinstalled in the biological system.