Lipophilicity is a critical parameter that dominates the efficacy of metalloporphyrins in blocking the development of morphine antinociceptive tolerance through peroxynitrite-mediated pathways

Batinic-Haberle, I; Ndengele, MM; Cuzzocrea, S; Reboucas, JS; Spasojevic, I; Salvemini, D

HERO ID

551569

Reference Type

Journal Article

Year

2009

Language

English

PMID

18983908

HERO ID 551569
In Press No
Year 2009
Title Lipophilicity is a critical parameter that dominates the efficacy of metalloporphyrins in blocking the development of morphine antinociceptive tolerance through peroxynitrite-mediated pathways
Authors Batinic-Haberle, I; Ndengele, MM; Cuzzocrea, S; Reboucas, JS; Spasojevic, I; Salvemini, D
Journal Free Radical Biology and Medicine
Volume 46
Issue 2
Page Numbers 212-219
Abstract Severe pain syndromes reduce the quality of life of patients with inflammatory and neoplastic diseases, partly because reduced analgesic effectiveness with chronic opiate therapy (i.e., tolerance) leads to escalating doses and distressing side effects. Peroxynitrite-mediated nitroxidative stress in the dorsal horn of the spinal cord plays a critical role in the induction and development of antinociceptive tolerance to morphine. This provides a valid pharmacological basis for developing peroxynitrite scavengers as potent adjuncts to opiates in the management of pain. The cationic Mn(III) ortho-N-alkylpyridylporphyrins MnTE-2-PyP5+ and MnTnHex-2-PyP5+ are among the most potent peroxynitrite scavengers, with nearly identical scavenging rate constants (~107 M- 1 s- 1). Yet, MnTnHex-2-PyP5+ is significantly more lipophilic and more bioavailable and, in turn, was 30-fold more effective in blocking the development of morphine antinociceptive tolerance than MnTE-2-PyP5+ using the hot-plate test in a well-characterized murine model. The hydrophilic MnTE-2-PyP5+ and the lipophilic MnTnHex-2-PyP5+ were 10- and 300-fold, respectively, more effective in inhibiting morphine tolerance than the hydrophilic Fe(III) porphyrin FeTM-4-PyP5+. Both Mn porphyrins decreased levels of TNF-[alpha], IL-1[beta], and IL-6 to normal values. Neither of them affected acute morphine antinociceptive effects nor caused motor function impairment. Also neither was able to reverse already established morphine tolerance. We have recently shown that the anionic porphyrin Mn(III) tetrakis(4-carboxylatophenyl)porphyrin is selective in removing ONOO- over O2-, but at ~ 2 orders of magnitude lower efficacy than MnTE-2-PyP5+ and MnTnHex-2-PyP5+, which in turn parallels up to 100-fold lower ability to reverse morphine tolerance. These data (1) support the role of peroxynitrite rather than superoxide as a major mechanism in blocking the development of morphine tolerance and (2) show that lipophilicity is a critical parameter in enhancing the potency of such novel peroxynitrite scavengers.
Doi 10.1016/j.freeradbiomed.2008.09.037
Pmid 18983908
Wosid WOS:000262491000012
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:000262491000012
Is Public Yes
Language Text English
Keyword Pain management; Morphine tolerance; Peroxynitrite; Nitrotyrosine; Mn porphyrins; MnTBAP; MnTE-2-PyP; MnTnHex-2-PyP; Peroxynitrite scavengers; Cytokines; Free radicals; SOD mimics
Is Qa No
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  • Has other version or edition: 975897