The Gut Microbiome Was Associated With Brain Structure and Function in Schizophrenia

Abstract The effects of the gut microbiome on the central nervous system and its possible role in mental disorders have received increasing attention. However, our knowledge about the relationship between the gut microbiome and brain structure and function is still very limited. Here, we leveraged 16S rRNA sequencing with structural magnetic resonance imaging (sMRI) and resting-state functional (rs-fMRI) to investigate differences in fecal microbiota between 38 patients with schizophrenia (SZs) and 38 demographically matched normal controls (NCs) and explored whether such differences were associated with brain structure and function. At the genus level, we found that the relative abundance of Ruminococcus and Roseburia was significantly lower, whereas the abundance of Veillonella was increased in SZs compared to NCs. Additionally, the MRI results revealed that several brain regions showed lower gray matter volume (GMV) and regional homogeneity (ReHo), but increased amplitude of low-frequency fluctuation (ALFF) in SZs than in NCs. Statistical analyses were performed to explore the associations between microbial shifts and brain structure and function. Alpha diversity of gut microbiota showed a strong linear relationship with GMV and ReHo. Moreover, we found that lower ReHo indexes in the right STC (r = -0.35, p = 0.031, FDR corrected p = 0.039), the left cuneus (r = -0.33, p = 0.044, FDR corrected p = 0.053) and the right MTC (r = -0.34, p = 0.03, FDR corrected p = 0.052) were negatively correlated with a lower abundance of the genus Roseburia. This study suggests that the potential role of the gut microbiome in schizophrenia (SZ) is related to the alteration of brain structure and function, suggesting a new direction for studying the pathology of SZ.