Abstract:
This study sought to examine the in vitro and in vivo protective properties of alkaloid extracts of two vegetables commonly consumed in the south-eastern part of Nigeria: Bush apple (Heinsia crinita) and Padauk (Pterocarpus soyauxii) as indices of their neuroprotective properties. The inhibitory effects of the extracts on acetylcholinesterase (AChE) activity, as well as on Fe2+, Al3+ and quinolinic acid (QA) – induced lipid peroxidation (in vitro) in Drosophila melanogaster homogenate were determined. Also, the Fe2+-chelating and free radical-scavenging abilities were assessed. The results showed that the extracts inhibited AChE activity, as well as Fe2+, Al3+ and quinolinic acid (QA) – induced lipid peroxidation in a concentration dependent manner. Both extracts also chelated Fe2+ and scavenged free radicals. The effective safe dose and the ameliorative abilities of the extracts on aluminium (Al)-induced toxicity in Drosophila melanogaster were assessed. The flies were exposed to 1.60 mg/g Al, the safe dose of the alkaloid extracts (16.6-1666.6 μg/g) and cotreatment of Al plus extracts, respectively. The survival and the locomotor performance of the flies were assessed after 7 days treatment, at which point they were homogenized and biochemical assays (AChE, BChE, Superoxide dismutase (SOD), Catalase (CAT), Glutathione-S- transferase (GST), malondialdehyde (MDA)) were carried out. The study reveals that Al-induced toxicity elevates AChE and BChE activities, and causes an increase in the activity of two endogenous antioxidant enzymes; SOD and GST while there is a decrease in the activity of CAT. Also, elevation in the production of MDA and reactive oxygen species (ROS) levels was observed. It also ameliorates the alterations induced by Aluminium in Drosophila melanogaster. The protective ability of these extracts against Al-induced toxicity can be associated with their anticholinergic and antioxidant properties. Thus, these vegetables can be potential sources of nutraceuticals in the management of diseases associated with Al-induced toxicity.
