Succinate accumulation in the colon increased epithelial fluid secretion and the immune response in piglets with diarrhea. a, b Gene expression of ANO9 (a) and CLCA1 (b) in colonic tissue determined by RT-qPCR. n = 6, Data are represented as mean ± SEM. **P < .01, determined by two-tailed Student’s t-test. c Protein qualification of ANO9 and CLCA1 in colonic tissue by the Wes Simple Western System. d Protein qualification of ANO9, CLCA1, NHE3 and DRA in IPEC-J2 cells. e Relative chloride level in the culture medium. f-h Gene expression of IRF1 (f), IRF7 (g) and TNF (h) in colonic tissue determined by RT-qPCR. n = 6, Data are represented as mean ± SEM. *P < .05, **P < .01, determined by two-tailed Student’s t-test. HEA, healthy piglets without diarrhea; DIA, diarrheal piglets. i Protein qualification of IRF7, IRF1, MyD88 and TLR4 in colonic tissue. j Protein qualification of SUCNR1 in RAW264.7 cells. k Protein qualification of IRF7, IRF1, MyD88 and TLR4 in RAW264.7 cells. l, m Levels of TNF-α (l) and IL-1β (m) in the culture medium. n = 3, Data are represented as mean ± SEM. *P < .05, determined by one-way ANOVA. CONT, control cells; SUC, cells treated with disodium succinate; TAK, cells treated with TAK-242; SUC+TAK, cells treated with disodium succinate and TAK-242.