CXCR4 antagonist AMD3100 attenuates colonic damage in mice with experimental colitis.
OBJECTIVE
To investigate the effects of the chemokine stromal cell-derived factor-1 (CXCL12) receptor (CXCR4) antagonist AMD3100 on colonic inflammation and epithelial barrier in dextran sulfate sodium (DSS)-induced colitis in mice.


METHODS
Experimental colitis was induced by administration of 5% DSS for 7 d, and assays performed on intestinal segments from the ileocecal valve to the anus. Colonic morphology was examined by hematoxylin and eosin staining. Colonic cytokines were determined by enzyme-linked immunosorbent assay. Myeloperoxidase (MPO) activity (indicator of inflammatory infiltration) was observed spectrophotometrically. Gut permeability was assessed by mucosal-to-serosal clearance of fluorescein isothiocyanate-conjugated dextran 4000 (FD4) in everted gut sacs. The apoptosis of colonic epithelium was assessed by Hoechst-33342 staining. To further elucidate the role of CXCR4 in colonic inflammation, we also investigated the effect of AMD3100 on migration and cytokine production of isolated peripheral blood mononuclear cells (PBMCs).


RESULTS
DSS-induced colitis was characterized by morphologic changes, as well as increased colonic cytokines, inflammatory infiltration, epithelial apoptosis, and intestinal permeability in mice. In AMD3100-treated mice, epithelial destruction, inflammatory infiltration, and submucosal edema were markedly reduced; colonic tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interferon-gamma (IFN-gamma) levels, as well as MPO activity were significantly decreased. Increased intestinal permeability in DSS-treated mice was significantly reduced by AMD3100. The number of apoptotic cells in colitis mice was markedly increased after DSS administration, and decreased when treated with the CXCR4 antagonist AMD3100. In pre-activated PBMCs, CXCL12 stimulation significantly increased the migration of PBMCs, and was inhibited by AMD3100. Moderately increased TNF-alpha, IL-6, and IFN-gamma from CXCL12-treated PBMCs were also reduced by AMD3100.


CONCLUSIONS
The CXCR4 antagonist AMD3100 exerts therapeutic effects on experimental colitis by inhibiting colonic inflammation and enhancing epithelial barrier integrity.
Xia
Xian-Ming
XM
Department of Gastroenterology and Hepatology, Jinling Hospital, Nanjing 210002, Jiangsu Province, China.
Wang
Fang-Yu
FY
Xu
Wen-An
WA
Wang
Zhen-Kai
ZK
Liu
Jiong
J
Lu
You-Ke
YK
Jin
Xin-Xin
XX
Lu
Heng
H
Shen
Yun-Zhu
YZ
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001596:Benzylamines; D002465:Cell Movement / Q000187:drug effects; D003092:Colitis / Q000139:chemically induced / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D003106:Colon / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D000080027:Cyclams; D016207:Cytokines / Q000378:metabolism; D016264:Dextran Sulfate / Q000633:toxicity; D005260:Female; D006571:Heterocyclic Compounds / Q000494:pharmacology*; D066298:In Vitro Techniques; D018836:Inflammation Mediators / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D010539:Permeability / Q000187:drug effects; D009195:Peroxidase / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000037:antagonists & inhibitors*
D001596:Benzylamines; C514936:CXCR4 protein, mouse; D000080027:Cyclams; D016207:Cytokines; D006571:Heterocyclic Compounds; D018836:Inflammation Mediators; D019718:Receptors, CXCR4; D016264:Dextran Sulfate; D009195:Peroxidase; C088327:plerixafor