Effects of arabinoxylan on BDNF/TrkB/p-CREB signaling pathway in the prefrontal cortex and intestinal microbiome in post-stroke depressed rats.

AIM

To explore the effects of arabinoxylan on the BDNF/TrkB/p-CREB signaling pathway in the prefrontal cortex of post-stroke depressed rats, and to explore its neuronal protective effects through the microbial-gut-brain axis in the regulation of this pathway.

METHODS

The rat model of post-stroke depression (PSD) was established by middle cerebral artery occlusion (MCAO) combined with chronic unpredictable mild stimulation (CUMS). They were randomly divided into 5 groups (blank control, post-stroke depression, arabinoxylan, fluoxetine hydrochloride, fluoxetine hydrochloride combined arabinoxylan). The rats were treated differently for 28 days according to their grouping. Body mass, sugar and water consumption experiments and open-field experiments were used to evaluate the behavior of rats. The pathological changes were observed by H&E staining. The expression levels of amine neurotransmitters were detected by ELISA. The expression levels of BDNF mRNA and BDNF, TrkB and p-CREB were detected by RT-PCR and Western blot. The analysis of intestinal metagenomics was conducted by 16 S rDNA sequencing.

RESULTS

Compared with the post-stroke depression group, the body weight, activity and sugar water consumption rate of the arabinoxylan group were increased. The expression levels of 5-HT in the prefrontal cortex, colon and serum levels of 5-HT, DA and NE were increased. The expression levels of BDNF mRNA and BDNF, TrkB and P-CREB in the prefrontal cortex were also upregulated. The number of neurons in the prefrontal cortex increased; Colon mucosal injury and inflammatory cell infiltration decreased, the intestinal microbial diversity increased; The relative abundance of probiotics such as bifidobacterium, Christensenia, Dubosiella New York and ruminococcus increased. The relative abundance of Prevotella NK3B31 group was reduced. The level of 5-HT in the prefrontal cortex was negatively correlated with the abundance of Prevotellaceae NK3B31 group.

CONCLUSION

Arabinoxylan improved depressive-like behavior in rats and its neuroprotective role was achieved by promoting the growth of intestinal probiotics, improving the intestinal barrier, affecting the BDNF/TrkB/p-CREB signaling pathway, and increasing the expression levels of monoamine neurotransmitters 5-HT, DA and NE.