Artesunate restores mitochondrial fusion-fission dynamics and alleviates neuronal injury in Alzheimer's disease models.

Alzheimer's disease (AD) remains a leading cause of dementia and no therapy that reverses underlying neurodegeneration is available. Recent studies suggest the protective role of artemisinin, an antimalarial drug, in neurological disorders. In this study, we investigated the therapeutic potential of artesunate, a water-soluble derivative of artemisinin, on amyloid-beta (Aß)-treated challenged microglial BV-2, neuronal N2a cells, and the amyloid precursor protein/presenilin (APP/PS1) mice model. We found that Aß significantly induced multiple AD-related phenotypes, including increased expression/production of pro-inflammatory cytokines from microglial cells, enhanced cellular and mitochondrial production of reactive oxygen species, promoted mitochondrial fission, inhibited mitochondrial fusion, suppressed mitophagy or biogenesis in both cell types, stimulated apoptosis of neuronal cells, and microglia-induced killing of neurons. All these in vitro phenotypes were attenuated by artesunate. In addition, the over-expression of the mitochondrial fission protein Drp-1, or down-regulation of the mitochondrial fusion protein OPA-1 both reduced the therapeutic benefits of artesunate. Artesunate also alleviated AD phenotypes in APP/PS1 mice, reducing Aß deposition, and reversing deficits in memory and learning. Artesunate protects neuronal and microglial cells from AD pathology, both in vitro and in vivo. Maintaining mitochondrial dynamics and simultaneously targeting multiple AD pathogenic mechanisms are associated with the protective effects of artesunate. Consequently, artesunate may become a promising therapeutic for AD.

Bilobalide alleviates neuroinflammation and promotes autophagy in Alzheimer's disease by upregulating lincRNA-p21.

EGb 761 has some protective effects on AD and can improve the cognitive functions of AD mice. However, the underlying molecular mechanisms are unknown. Here, we investigated the function of bilobalide, the effective component of EGb 761, in neuroinflammation and autophagy during AD. LPS-treated BV-2 cells were used as an in vitro model for neuroinflammation. The APP/PS1 AD mouse line was used to examine the function of bilobalide in AD. ELISA and qRT-PCR were used to measure the levels of proinflammatory cytokines, including TNF-α, IL-6 and IL-1ß. Western blotting was employed to determine the protein levels of p-p65, iNOS, COX-2, LC3, beclin-1, p62 and p-STAT3. Immunostaining was applied to examine the number of autophagosomes. LPS treatment induced inflammatory responses and inhibited autophagy in BV-2 cells. Bilobalide suppressed LPS-induced neuroinflammation and promoted autophagy. Furthermore, bilobalide treatment increased the lincRNA-p21 levels, which suppressed STAT3 signalling. Knockdown of lincRNA-p21 reversed the effects of bilobalide. Overexpression of lincRNA-p21 promoted autophagy and inhibited neuroinflammation as well while STAT3 inhibitor blocked the effects of si-lincRNA-p21. In vivo experiments revealed that bilobalide improved the learning and memory capabilities of APP/PS1 AD mice. Bilobalide improves the cognitive functions of APP/PS1 AD mice. Mechanistically, bilobalide suppresses inflammatory responses and promotes autophagy possibly by upregulating lincRNA-p21 levels.