Background: Osthole, a natural coumarin, found in many medicinal plants. Previous studies have shown its neuroprotective effects, whereas the effect and fundamental mechanism of Osthole for alleviating AD-associated dysmnesia is still not fully clear.
Purpose: This study aimed to examine the neuroprotection of Osthole against cognitive impairment in the D-galactose-induced rats and its pharmacological mechanism.
Method: The rat was constructed by subcutaneous injection of D-galactose at a dose of 150 mg/kg/day for 56 days as a model. The effect of Osthole on cognitive impairment was evaluated by behavior and biochemical analysis. Subsequently, a combination of in silico prediction and experimental validation was performed to determine the underlying mechanisms of Osthole against Alzheimer's disease, while to verify the network-based predictions, western blot, Nissl staining, and immunofluorescence were applied.
Result: Osthole could improve memory dysfunction induced by D-galactose in Sprague Dawley male rat. Endophenotype-based network approach highlight several AD-related pathological processes that may be regulated by Osthole, including neuronal apoptosis, neuroinflammationand endoplasmic reticulum stress. Among them, the proapoptotic markers (Bax), antiapoptotic protein (Bcl-2), moreover, the microgliosis (Iba-1), Astrocytosis (GFAP), and inflammatory cytokines (TNF-α1), levels of ER stress-associated proteins (BIP, p-PERK/PERK, Caspase12, CHOP and XBP1s) were evaluated in both hippocampus and cortex. And the results indicated that Osthole significantly ameliorated neuronal apoptosis, neuroinflammation and ER stress in D-galactose induced rats.
Conclusion: This study explored the pharmacological mechanism of Osthole against D-galactose induced memory impairment and identified Osthole as a potential anti-AD drug candidate targeting multiple signaling pathways by endophenotype network-based.