Fig. 3

Elimination of oral microbiota weakens nitrate's protective effects on cognition and inflammation in alcohol-exposed mice. A Schematic diagram showing the study design for oral microbiota removal. B The changes in body weight during six weeks (n = 13–14). C and D Behavioral tests showed that spontaneous alternation in the Y-maze test were significantly decreased in Chlorhexidine (CHX) group compared with Control (Ctrl) group, while novelty preference in the NOR test decreased with no statistic difference (n = 13–14). E–G Quantification of the number of Iba1-positive microglia in the CA1, CA3 and DG (n = 13–14). H and J Quantification of the number of Iba1-positive microglia in the vmPFC and dmPFC (n = 13–14). I Representative images of Iba1 immunofluorescence in the CA1, CA3, DG (hippocampus) and dmPFC, vmPFC (medial prefrontal cortex, mPFC), Scale bar = 100 μm. Higher definition picture was shown in Supplementary Fig. 7. K–N Significant increases in the proinflammatory cytokines IL-1β and IL-6 were found in brain tissue in the CHX group, compared with group Ctrl. TNF-α and IL-10 in brain tissue showed no significant difference between the two groups (n = 12 per group). O S100β in the serum showed no significant difference between the two groups (n = 12 per group). The data are expressed as the mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001