Boophone Haemanthoides (Amaryllidaceae) and Its Bioactive Compounds Attenuate MPP+-Induced Toxicity in an in Vitro Parkinson’s Disease Model

Parkinson’s disease (PD) is a neurodegenerative disease that progresses with increasing age and some of its major symptoms include tremor, postural and movement related difficulties. Till date, the treatment of PD remains a challenge because available drugs only treat the symptoms of the disease or possess serious side effects. In light of this, new treatment options are needed, hence this study investigates the neuroprotective effects of an organic Boophone haemanthoides extract (BHE) and its bioactive compounds using an in vitro model of PD involving the toxin 1-methyl-4-phenylpyridinium (MPP+) and SH-SY5Y neuroblastoma cells. A total of seven compounds were isolated from BHE viz: distichamine (1), 1α,3α-diacetylnerbowdine (2), hippadine (3), stigmast-4-ene-3, 6-dione (4), cholest-4-en-3-one (5), tyrosol (6), and 3-hydroxy-1-(4`-hydroxyphenyl)-1-propanone (7). Six compounds (1, 2, 4, 5, 6, 7) were investigated and five showed neuroprotection alongside the BHE. This study gives insight into the bioactivity of the non-alkaloidal constituents of Amaryllidaceae since the isolated compounds and the BHE showed improved cell viability, increased ATP generation in the cells as well as inhibition of MPP+-induced apoptosis. Together, these findings support the claim that the Amaryllidaceae plant family could be a potential reserve of bioactive compounds for the discovery of neuroprotective agents.