Fig. 2

Effects of Paenalcaligenes hominis on the occurrence of cognitive impairment and colitis in germ-free mice. a Effects on the occurrence of cognitive impairment in Y-maze task. b Effects on the BDNF expression and NF-κB activation in the hippocampus. Effects on BDNF⁺/NeuN⁺ (c), NF-κB⁺/Iba1⁺ (d), LPS⁺/Iba1⁺ (e), and IL-1R⁺ cell populations (f) in the hippocampus. g Effects on the IL-1β expression in the blood, assessed by ELISA. Effects on the colon length (h), myeloperoxidase (MPO) activity (i), IL-1β level (j), and NF-κB⁺/CD11c⁺ cell population (k) in the colon. Paenalcaligenes hominis (PH, 1 × 10⁷ CFU/mouse/day) were orally gavaged once a day for 5 days. Control mice (NC) were treated with vehicle (saline) instead of PH. Data values were indicated as mean ± SD (n = 4). *p < 0.05 vs. NC group. a, g, h, i Two-tailed Mann-Whitney U test. j One-tailed Mann-Whitney U test