Abstract 111: A Kidney Targeted Epoxyeicosatrienoic Acid Analog, EET-F01, Reduces Cisplatin-induced Nephrotoxicity

Abstract

Epoxyeicosatrienoic acid (EET) analogs have exceptional therapeutic potential to combat cardiovascular and kidney diseases. EET analogs combat damage in acute and chronic kidney disease models. Biological actions attributed to EET analogs such as vasodilation, anti-inflammation, anti-apoptosis, and anti-fibrosis are ideally suited to treat kidney diseases. Although EET analogs have performed well in several in vivo models, targeted delivery of EET analogs to the kidney can be reasonably expected to reduce the level of drug needed to achieve a therapeutic effect in the kidney and obviate possible side effects. For EET analog kidney-targeted delivery, we conjugated an EET analog to folic acid because there is a high concentration of folate receptors in renal tissue. The EET analog was conjugated to folic acid via a PEG-diamine linker. Next, we compared the kidney targeted EET analog, EET-F01, to a well-studied EET analog, EET-A. EET-A or EET-F01 was infused i.v. (10mg/kg/hr) for 6 hours via the rat jugular vein. Plasma and kidney tissue were collected and EET-A or EET-F01 measured by LC-MS-MS. EET-A plasma level was 1.6 ng/mL, but EET-A was undetectable in the kidney. On the other hand, EET-F01 was 6.5 ng/mL in plasma and 26.7 ng/mL in kidney tissue. These data demonstrate that EET-F01 targets the kidney. Experiments were conducted to compare EET-F01 and EET-A to decrease cisplatin-induced nephrotoxicity. A single injection of cisplatin (7 mg/kg ip) was administered to WKY rats treated with vehicle, EET-A (10 mg/kg ip) or EET-F01 (20 mg/kg or 2 mg/kg ip) for five days. Cisplatin increased BUN (125 ± 11 mg/dL) and NAG (12 ± 4 IU/L) compared to control (36 ± 9 mg/dL and 4 ± 1 IU/L). EET-F01 was as effective as EET-A in decreasing BUN, NAG, and renal histological injury five days following cisplatin administration. Despite it almost 2x-greater molecular weight compared with EET-A, EET-F01 was effective in lowering BUN and NAG at 20 mg/kg/d and at a 10-fold lower dose of 2 mg/kg/d. These data clearly demonstrate that EET-F01 targets the kidney and allows for a lower effective dose. In conclusion, we have developed a kidney targeted EET analog, EET-F01, that demonstrates excellent potential as a therapeutic for kidney diseases.