TREPROSTINIL IMPROVES HEPATIC CYTOCHROME P450 METABOLISM DURING RENAL ISCHEMIA REPERFUSION INJURY
Date of Award
Master of Science in Pharmaceutical Sciences
Biomedical and Pharmaceutical Sciences
Background: Renal ischemia-reperfusion injury (IRI) causes acute kidney injury, as well as liver injury resulting in altered hepatic metabolism. Decreased hepatic cytochrome P450 levels can impact drug clearance and increase the risk for adverse drug reactions. Currently, there is no treatment available to improve liver cyp450 metabolism during renal IRI. Treprostinil (Remodulin®) is a FDA approved prostacyclin analog that our lab has shown to have hepatoprotective effects during renal IRI. This study investigates the efficacy of treprostinil on improving hepatic cyp450 metabolism during renal IRI in vivo.
Methods: Male Sprague Dawley rats were subjected to 45 minutes of bilateral renal ischemia, followed by 1-48 hours of reperfusion. The animals were divided into three groups: sham, IRI-placebo, and IRI-treprostinil. Placebo or treprostinil (100 ng/kg/min) were administered subcutaneously. Liver tissue and serum were collected for analysis. Cyp450 protein and mRNA expression were measured by western blot analysis and qRT-PCR, respectively. Formation rates of 6β-hydroxytestosterone, 16ɑ-hydroxytestosterone and 2ɑ-hydroxytestosterone served as probes for cyp3a2 and cyp2c11 activity.
Results: Treprostinil significantly reduced serum creatinine, BUN, ALT and AST levels vs. IRI-placebo (P < 0.001). Treprostinil increased the hepatic mRNA expression of major rat cyp450 enzymes, e.g., cyp3a2 (P < 0.05) and cyp2c11, vs. IRI-placebo. Proteomic analysis shows that treprostinil increased the hepatic protein expression of important drug metabolizing cyp450 enzymes, such as cyp2e1, cyp2c13 (P < 0.05), cyp3a1, and cyp3a2. In addition, treprostinil increased hepatic cyp3a2 and cyp2c11 protein expression by over 4-fold and 1.5-fold, respectively, vs. IRI-placebo. Treprostinil also improved hepatic cyp3a2 activity by 81% when compared to IRI-placebo animals.
Conclusions: Treprostinil reduced liver and kidney dysfunction during renal IRI. Treprostinil also improved hepatic cyp450 metabolism by increasing cyp450 mRNA, protein, and activity. This study provides evidence that treprostinil may be a novel therapy to improve hepatic cyp450 metabolism during renal IRI, thus reducing risk of toxicities or subtherapeutic concentrations of drug for patients experiencing renal IRI.
Kelly, Daniel, "TREPROSTINIL IMPROVES HEPATIC CYTOCHROME P450 METABOLISM DURING RENAL ISCHEMIA REPERFUSION INJURY" (2022). Open Access Master's Theses. Paper 2282.
Available for download on Wednesday, July 12, 2023