Tissue Distribution Study On Apocynin Nitrone Derivative AN-1 After Intravenous Administration

Abstract

Background  Apocynin, a main component extracted from the root of Picrorhiza kurroa Royle, was a well-known NADPH oxidase inhibitor and reported to have effect on lung injury, liver injury, diabetes and asthma. AN-1, a nitrone derivative of apocynin, was found to exhibit significant effect on treatment of acute lung injury.

Aim In order to carry out further preclinical study, it is important to reveal in vivo disposition of AN-1. A simple and rapid high-performance liquid chromatography (HPLC) method was developed to disclose the tissue distribution behavior of AN-1 in Sprague-Dawley (SD) rats.

Methods A HPLC method was developed and validated to measure the concentration of AN-1 in tissue samples with carbamazepine as internal standard (IS). The mobile phase consisted of water and methanol (47:53, v/v), the ?ow rate was 1 mL/min, and an ultraviolet (UV) detector was used at wavelength of 279 nm. The tissue distribution study of AN-1 was performed in Sprague-Dawley (SD) rats after a single intravenous dose of 40 mg/kg.

Results The developed HPLC-UV method was of good specificity, precision (< 4%), accuracy (90-97%) and recovery (88-104%) for analysis of AN-1 in tissue samples of rats. The linear range was established over a concentration range 0.2-50 µg/mL (r² > 0.998) in tissues including heart, liver, spleen, lung, kidney and brain. After administration, AN-1 was rapidly distributed in tissues and reached peak concentration with time, which showed a high distribution in liver and kidney. It demonstrated a longer T_1/2 and higher deposition of AN-1 in lung when compared with parent compound apocynin.

Conclusion The results showed increased lung distribution of active ingredient after nitrone derivation of apocynin. It may well elucidate the more potential efficacy of AN-1 in acute lung injury treatment and support further development of AN-1 as a promising candidate.