Conclusions
Our study showed that the gut microbiota composition of the depressive-like rats markedly differed from their controls, which may be of value for future microbiota-targeted work in this and similar animal models.
Methods
We characterized the gut microbiota of male adult Flinders sensitive line (FSL) rats, an animal model of depression, and their controls, Flinders resistant line (FRL) rats using 16S rRNA amplicon sequencing. Moreover, we performed fecal microbiota transplantation (using saline or pooled FRL/FSL feces) to study if the potential strain-specific differences could be transferred from one strain to the other, and if these differences were reflected in their depressive-like behavior in the forced swim test.
Results
FSL rats tended to have lower bacterial richness and altered relative abundances of several bacterial phyla, families, and species, including higher Proteobacteria and lower Elusimicrobia and Saccharibacteria. There was a clear separation between FRL and FSL rat strains, but no effect of treatment, i.e., the bacterial composition of FSL rats receiving FRL feces was still more similar to FSL and not FRL rats. Similarly, the transplantation did not reverse behavioral differences in the forced swim test, although FSL feces significantly increased immobility compared with saline. Conclusions: Our study showed that the gut microbiota composition of the depressive-like rats markedly differed from their controls, which may be of value for future microbiota-targeted work in this and similar animal models.