Embelin prevents amyloid-beta accumulation via modulation of SOD1 in a Streptozotocin-induced AD-like condition: An evidence from in vitro investigation

Embelin is a neuroprotective compound with therapeutic benefit against experimental Alzheimer's disease (AD)-like condition. In the quest of untangling the underlying mechanism behind the neuroprotective effect of Embelin in AD, an in-vitro study of Embelin against neuronal damage induced by Streptozotocin (STZ) in rat hippocampal neuronal culture was performed. Current findings demonstrated that Embelin (2.5-10 μM) has efficiently protected hippocampal neurons against STZ (8 mM)-induced neurotoxicity. An increase in amyloid precursor protein (APP), microtubule-associated protein tau (MAPT), glycogen synthase kinase 3 alpha (GSK-3α) and glycogen synthase kinase 3 beta (GSK-3β) expression levels was observed when STZ (8 mM) stimulation was done for 24 h in the hippocampal neurons. A significant downregulation in the mRNA expression levels of APP, MAPT, GSK-3α, and GSK-3β upon pre-treatment with different doses of Embelin (2.5 μM, 5 μM and 10 μM) reflects that Embelin attenuated STZ-induced dysfunction of insulin signaling (IR). Embelin significantly modulated the mRNA expression of scavenger enzyme Superoxide dismutase (SOD1). Furthermore, STZ had significantly upregulates an expression of Aβ. On the contrary, pre-treatment with three doses of Embelin reversed an Aβ-induced neuronal death. Our findings suggest that, Embelin prevents Aβ accumulation via SOD1 pathway to protect against AD-like condition.