Celastrol alleviates comorbid obesity and depression by directly binding
amygdala hnRNPA1 in a mouse model
Abstract
Background and Purpose: Obesity and depression are highly comorbid and
far from effective treating. Celastrol was reported useful for obesity,
but its role in the obesity-depression comorbidity remains unknown. This
study aims to investigate the efficacy and associated mechanism of
celastrol in this comorbidity. Experimental Approach: A comorbidity mice
model of obesity and depression were constructed. Bodyweight, adipose
tissue rate, blood glucose, and blood lipids were used to assess
obesity. Forced swimming test and tail suspension test were investigated
to evaluate depression. In microglial cells, direct targets of celastrol
were screened and determined by chemical proteomics, pull-down
experiment, and competitive binding assay. In the mice model, the target
gene’s mediating effect was investigated by stereotactic injection of
AAV9 virus. The expression level of target molecules was detected by
immunofluorescence. Key Results: Celastrol relieved the comorbid
symptoms, inhibited the mal-activated Neuropeptide Y, and activated the
mal-inhibited 5-HT neurons in the amygdala. The efficacy was associated
with the inhibition of the mal-activated microglia. Chemical proteomics,
pull-down experiment, and competitive binding assay results indicated
celastrol’s directly binding hnRNPA1. In the animal model,
downregulation of hnRNPA1 in the amygdala relived symptoms and NPY and
5-HT neurons’ changes. Meanwhile, overexpression of hnRNPA1 aggravated
the comorbidity and antagonized the effect of celastrol. Conclusion and
Implications: Celastrol alleviated comorbid obesity and depression in a
mouse model by directly binding hnRNPA1 in the amygdala. Celastrol may
become a potential drug, and hnRNPA1 in the amygdala could be a useful
target to combat the comorbidity.