Omaveloxolone ameliorates cognitive dysfunction in APP/PS1 mice by stabilizing the STAT3 pathway

Abstract

Aims: To determine the availability and the potential molecular mechanisms underlying the therapeutic effect of omaveloxolone (RTA408) on Alzheimer's Disease (AD).

Materials and methods: This study employed network pharmacology to assess the feasibility of drug treatment of AD. To determine the cognitive status and emotional state of APPswe/PS1dE9 (APP/PS1) mice after the RTA408 treatment, three classical behavioral experiments (water maze, Y-maze, and open field test) were conducted. Immunofluorescence and immunohistochemical staining were utilized to evaluate hippocampal neuronal status and amyloid (Aβ) deposition in mice. RNA-seq and transcription factor prediction analyses were performed to explore the potential molecular mechanisms regulating the therapeutic effects of RTA408. Molecular docking was employed to predict the direct drug targets. To validate these molecular mechanisms, quantitative reverse transcription PCR (qRT-PCR), Western blotting, and immunofluorescence analyses were performed in two instrumental cell lines, i.e., mouse hippocampal neuronal cells (HT22) and microglia (BV2).

Results: RTA408 was revealed with the capability to reduce Aβ plaque deposition and to restore damaged neurons in the hippocampal region of APP/PS1 mice, ultimately leading to an improvement in cognitive function. This beneficial effect was achieved by balancing the STAT3 pathway. Specifically, RTA408 facilitated the activations of both STAT3/OXR1 and NRF2/ARE axes, thereby enhancing the compromised resistance in neurons to oxidative stress. RTA408 inhibited the NFκB/IL6/STAT3 pathway, effectively countering the neuroinflammation triggered by microglial activation.

Conclusion: RTA408 is revealed with promising potential in the treatment of AD based on preclinical data.

Keywords: Alzheimer's disease; Neuroinflammation; OXR1; Omaveloxolone; Oxidative stress; STAT3.