Andrographolide ameliorates neuroinflammation in APP/PS1 transgenic mice

Alzheimer's disease is a devastating neurodegenerative disorder, with no disease-modifying treatment available yet. There is increasing evidence that neuroinflammation plays a critical role in the pathogenesis of AD. Andrographolide (Andro), a labdane diterpene extracted from the herb Andrographis paniculata, has been reported to exhibit neuroprotective property in central nervous system diseases. However, its effects on Aβ and Aβ-induced neuroinflammation have not yet been studied. In the present study, we found that Andro administration significantly alleviated cognitive impairments, reduced amyloid-β deposition, inhibited microglial activation, and decreased the secretion of proinflammatory factors in APP/PS1 mice. Furthermore, transcriptome sequencing analysis revealed that Andro could significantly decrease the expression of Itgax, TLR2, CD14, CCL3, CCL4, TLR1, and C3ar1 in APP/PS1 mice, which was further validated by qRT-PCR. Our results suggest that Andro might be a potential therapeutic drug for AD by regulating neuroinflammation.