The renoprotective effect of IAld and L. johnsonii administration were associated with inhibiting AHR signaling pathway. a Serum creatinine and urea levels and CCr in the control, CRF and different doses of IAld-treated CRF rats. b Images of H&E-stained kidney tissues in the control, CRF and IAld-treated CRF rats. Scale bar, 70 μm. c Images of Masson’s trichrome-stained kidney tissues in the control, CRF and IAld-treated CRF rats. Scale bar, 90 μm. d Immunohistochemical findings with anti-α-SMA of kidney tissues in the control, CRF and IAld-treated CRF rats. Scale bar, 70 μm. e Protein expression of collagen I, α-SMA, fibronectin and E-cadherin of kidney tissues in control, CRF and IAld-treated CRF rats. f Quantitative analysis of collagen I, α-SMA, fibronectin and E-cadherin of kidney tissues in the control, CRF and IAld-treated CRF rats. g Protein expression of collagen I, α-SMA, fibronectin and E-cadherin of kidney tissues in the Sham, UUO and IAld-treated UUO rats. h Quantitative analysis of collagen I, α-SMA, fibronectin and E-cadherin of kidney tissues in the Sham, UUO and IAld-treated UUO rats. i The mRNA levels of AHR and its target genes including CYP1A1, CYP1A2, CYP1B1 and COX-2 of kidney tissues in the control, CRF and different doses of IAld-treated CRF rats. j Immunohistochemical analysis with anti-AHR of kidney tissues in the control and CRF rats. k Protein expression of AHR in cytoplasm and nuclei of kidney tissues in the control, CRF and IAld-treated CRF rats. l Quantitative analysis of AHR expression in cytoplasm and nuclei of kidney tissues in the control, CRF and IAld-treated CRF rats. m Obstructed intrarenal mRNA levels of AHR and its target genes including CYP1A1, CYP1A2, CYP1B1 and COX-2 in the Sham, UUO and IAld-treated UUO rats. n Protein expression of AHR in cytoplasm and nuclei of kidney tissues in the Sham, UUO and IAld-treated UUO rats. *P < 0.05; **P < 0.01 compared with control or sham rats (n = 6/group). #P < 0.05; ##P < 0.01 compared with CRF or UUO rats (n = 6/group). Data are represented as mean ± SEM