TY - JOUR
T1 - Failure of desferrioxamine to modify the toxicity of paraquat in rats
AU - Osheroff, Merrill R.
AU - Schaich, Karen
AU - Drew, Robert T.
AU - Borg, Donald C.
PY - 1985/1/1
Y1 - 1985/1/1
N2 - The feasibility of using desferrioxamine (DF), an iron chelator, as a therapeutic agent against paraquat (PQ++) toxicity in male Sprague-Dawley rats was explored, based on the rationale of limiting toxic hydroxyl radical production from hydrogen peroxide by removing redox-active iron. Body weights, mortality, and lung histopathology were followed for periods up to 14 days after intraperitoneal injection of PQ++ (20 or 25 mg/kg body weight) with or without concurrent daily subcutaneous injections of DF (300 mg/day). Animals receiving PQ++ showed the expected typical patterns of mortality and of lung histopathology, namely: marked edema, subpleural hemorrhage, acute inflammation, perivascular mononuclear cell infiltrates, sloughing of alveolar and bronchiolar lining cells, and diffuse interstitial fibrosis. Desferrioxamine alone was non-toxic. Surprisingly, results when both PQ++ and DF were administered indicated a failure of DF to ameliorate toxic effects of PQ++ in the lung, and even suggested an accentuation of PQ++-induced damage by DF. Mortality data showed that PQ++/DF animals died in greater numbers (20 mg PQ++/kg) or died earlier (25 mg PQ++/kg) than animals receiving DF alone. Qualitative histopathology in PQ++/DF animals was comparable to PQ++ animals in early stages, but damage was more severe in both incidence and severity of lesions in PQ++/DF animals, particularly at the 25 mg PQ++/kg dose level. After 14 days, surviving animals receiving PQ++ alone showed almost complete resolution of previous inflammation and other acute effects, whereas in the only surviving PQ++/DF animal initial fibrosis had persisted and become more generalized. Thus, chelation therapy with DF may not be straightforward in its effects on PQ++ toxicity.
AB - The feasibility of using desferrioxamine (DF), an iron chelator, as a therapeutic agent against paraquat (PQ++) toxicity in male Sprague-Dawley rats was explored, based on the rationale of limiting toxic hydroxyl radical production from hydrogen peroxide by removing redox-active iron. Body weights, mortality, and lung histopathology were followed for periods up to 14 days after intraperitoneal injection of PQ++ (20 or 25 mg/kg body weight) with or without concurrent daily subcutaneous injections of DF (300 mg/day). Animals receiving PQ++ showed the expected typical patterns of mortality and of lung histopathology, namely: marked edema, subpleural hemorrhage, acute inflammation, perivascular mononuclear cell infiltrates, sloughing of alveolar and bronchiolar lining cells, and diffuse interstitial fibrosis. Desferrioxamine alone was non-toxic. Surprisingly, results when both PQ++ and DF were administered indicated a failure of DF to ameliorate toxic effects of PQ++ in the lung, and even suggested an accentuation of PQ++-induced damage by DF. Mortality data showed that PQ++/DF animals died in greater numbers (20 mg PQ++/kg) or died earlier (25 mg PQ++/kg) than animals receiving DF alone. Qualitative histopathology in PQ++/DF animals was comparable to PQ++ animals in early stages, but damage was more severe in both incidence and severity of lesions in PQ++/DF animals, particularly at the 25 mg PQ++/kg dose level. After 14 days, surviving animals receiving PQ++ alone showed almost complete resolution of previous inflammation and other acute effects, whereas in the only surviving PQ++/DF animal initial fibrosis had persisted and become more generalized. Thus, chelation therapy with DF may not be straightforward in its effects on PQ++ toxicity.
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U2 - 10.1016/0748-5514(85)90032-7
DO - 10.1016/0748-5514(85)90032-7
M3 - Article
C2 - 3013974
AN - SCOPUS:0022396302
VL - 1
SP - 71
EP - 82
JO - Journal of Free Radicals in Biology and Medicine
JF - Journal of Free Radicals in Biology and Medicine
SN - 0748-5514
IS - 1
ER -