Amelioration of murine dextran sulfate sodium-induced colitis by ex vivo extracellular superoxide dismutase gene transfer.
BACKGROUND
Although the etiology of inflammatory bowel disease has not been fully clarified, reactive oxygen species is speculated to be involved. Extracellular superoxide dismutase (EC-SOD), an isozyme of SODs, is known to function mainly in body fluids. We investigated the efficacy of an ex vivo EC-SOD gene transfer into dextran sulfate sodium (DSS)-induced colitis mice.


METHODS
Experimental colitis was induced by providing Balb/c mice with DSS in sterile distilled water provided as desired. The syngenic fibroblasts were obtained from Balb/c mice embryos and retrovirally transduced with the hEC-SOD gene. These engineered cells were confirmed to secrete EC-SOD in culture medium by enzyme-linked immunosorbent assay and were inoculated subcutaneously in the backs of DSS-treated mice. Mucosal injury of the colon was evaluated by the disease activity index (DAI: body weight, rectal bleeding, and stool consistency), grading of histologic disease severity, and levels of cytokine (tumor necrosis factor-alpha, interleukin-1beta) production. 8-Hydroxydeoxyguanosine (8-OHdG) levels in the mucosal tissue were assessed by immunohistochemical staining. Malondialdehyde (MDA) was measured using a colorimetric assay.


RESULTS
A significant improvement was observed in DAI score and histologic severity as well as in mucosal tissue levels of inflammatory cytokines, 8-OHdG, and MDA of mice treated with the EC-SOD gene as compared with those without gene therapy, not only in a mild colitis model but also in a severe colitis model. Survival of treated mice in these models was significantly prolonged.


CONCLUSIONS
Ex vivo transfer of the EC-SOD gene was feasible for treatment of DSS-induced colitis.
Oku
Takatomi
T
Department of Internal Medicine (Section 4), Sapporo Medical University, School of Medicine, Sapporo, Japan.
Iyama
Satoshi
S
Sato
Tsutomu
T
Sato
Yasushi
Y
Tanaka
Maki
M
Sagawa
Tamotsu
T
Kuribayashi
Kageaki
K
Sumiyosi
Tetsuya
T
Murase
Kazuyuki
K
Machida
Takuro
T
Okamoto
Tetsuro
T
Matsunaga
Takuya
T
Takayama
Tetsuji
T
Takahashi
Minoru
M
Kato
Junji
J
Hamada
Hirofumi
H
Niitsu
Yoshiro
Y
D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology; D003092:Colitis / Q000139:chemically induced* / Q000628:therapy*; D003470:Culture Media / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D016264:Dextran Sulfate / Q000494:pharmacology*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D007150:Immunohistochemistry; D007249:Inflammation; D008315:Malondialdehyde / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D017382:Reactive Oxygen Species; D013482:Superoxide Dismutase / Q000378:metabolism*
D000925:Anticoagulants; D003470:Culture Media; D016207:Cytokines; D017382:Reactive Oxygen Species; D008315:Malondialdehyde; D016264:Dextran Sulfate; D013482:Superoxide Dismutase