Mn(III) tetrakis(N-ethylpyridinium-2-yl)porphyrin, MnTE-2-PyP5+, a potent catalytic superoxide and peroxynitrite scavenger, has been beneficial in several oxidative stress-related diseases thus far examined. Pharmacokinetic studies are essential for the better assessment of the therapeutic potential of MnTE-2-PyP5+ and similar compounds, as well as for the modulation of their bioavailability and toxicity. Despite high hydrophilicity, this drug entered mitochondria after a single 10 mg/kg intraperitoneal injection at levels high enough (5.1 μM; 2.95 ng/mg protein) to protect against superoxide/peroxynitrite damage. Utilizing the same analytical approach, which involves the reduction of MnTE-2-PyP5+ followed by the exchange of Mn2+ with Zn2+ and HPLC/fluorescence detection of ZnTE-2-PyP4+, we measured levels of MnTE-2-PyP5+ in mouse plasma, liver, kidney, lung, heart, spleen, and brain over a period of 7 days after a single intraperitoneal injection of 10 mg/kg. Two B6C3F1 female mice per time point were used. The pharmacokinetic profile in plasma and organs was complex; thus a noncompartmental approach was utilized to calculate the area under the curve, cmax, tmax, and drug elimination half-time (t1/2). In terms of levels of MnTE-2-PyP5+ found, the organs can be classified into three distinct groups: (1) high levels (kidney, liver, and spleen), (2) moderate levels (lung and heart), and (3) low levels (brain). The maximal levels in plasma, kidney, spleen, lung, and heart are reached within 45 min, whereas in the case of liver a prolonged absorption phase was observed, with the maximal concentration reached at 8 h. Moreover, accumulation of the drug in brain continued beyond the time of the experiment (7 days) and is likely to be driven by the presence of negatively charged phospholipids. For tissues other than brain, a slow elimination phase (single exponential decay, t1/2 = 60 to 135 h) was observed. The calculated pharmacokinetic parameters will be used to design optimal dosing regimens in future preclinical studies utilizing this and similar compounds.
|Number of pages||7|
|Journal||Free Radical Biology and Medicine|
|State||Published - Oct 1 2008|
Bibliographical noteFunding Information:
Ivan Spasojević acknowledges NIH/NCI Duke Comprehensive Cancer Center Core grant (5-P30-CA14236-29). Ines Batinić-Haberle appreciates financial support from NIH-IR21-ESO/3682 and NIH U19 AI67798-01/pilot project. Yumin Chen, Teresa Noel, and Daret St. Clair are thankful for the support of NIH Grants CA 49797, CA 73599, and CA 94853. We are thankful to Huaxin Sheng for his help with animal perfusion and Irwin Fridovich for critically reading the manuscript.
- AEOL 10113
- Free radicals
- Pharmacokinetics in mouse organs
- Pharmacokinetics in mouse plasma
- Pharmacokinetics in mouse tissues
- SOD mimic
ASJC Scopus subject areas
- Physiology (medical)