Fig. 3: CYP27A1 is upregulated during intestinal injury and promotes intestinal regeneration.
From: Liver X receptor unlinks intestinal regeneration and tumorigenesis
a, Schematic of cholesterol metabolism to oxysterols by the cytochrome P450 monooxygenase family of enzymes (CYPs) and its downstream action on LXR. b, The average expression (colour coded) and the percentage of cells (circle size) expressing oxysterol-producing enzymes in SI crypts at 0 (Ctrl) or 3 d.p.i. (irrad.)4. c, Heatmap of oxysterol-producing enzyme expression in whole-colonic tissue during DSS kinetics5 (log2-transformed fold change compared with day 0). Diff., differentially. d, qPCR analysis of Cyp27a1 in ileal crypts from DSS-treated WT mice. e, Immunohistochemical quantification of CYP27A1 in the SI of WT mice at the indicated d.p.i. f, qPCR analysis of Cyp27a1 in FACS-sorted EPCAM+ epithelial (IEC), CD45+ immune (imm. IEL and imm. LP) and EPCAM−CD45− DN cells from WT mouse SI collected at the indicated d.p.i. g, qPCR analysis of Abca1 in FACS-sorted IECs from WT mouse SI collected at the indicated d.p.i. IEL, intraepithelial lymphocyte; LP, lamina propria. h, qPCR analysis of Cyp27a1 and Abca1 in FACS-sorted IECs from Cyp27a1−/− mice and littermate control SI at 3 d.p.i. i, Representative images and quantification of BrdU+ surviving crypts from the SI at 3 d.p.i. Crypts in the same plane are marked by a dashed line. Scale bars, 50 μm. j, qPCR analysis of CYP27A1 and ABCA1 in human intestinal biopsies (collected from terminal ileum (square symbols), ascending colon (triangle symbols), transverse colon (diamond symbols) and sigmoid rectum (hexagon symbols)) from healthy control individuals (n = 28), and patients with active ulcerative colitis (UC) (n = 39) and ulcerative colitis in remission (n = 27). Data are representative of two (d,f–h) or three (e,i) independent experiments with 3–10 mice per condition (each dot represents one biological replicate). Data are mean ± s.e.m. (d–h) and median ± quartiles (i,j). Significance was assessed using unpaired two-tailed t-tests (h), one-way ANOVA with Tukey’s post hoc test (d–g), Fisher’s LSD post hoc test (i) and nonparametric Kruskal–Wallis test with uncorrected Dunnett’s post hoc test (j).
