Rutin loaded bilosomes for enhancing the oral activity and nephroprotective effects of rutin in potassium dichromate induced acute nephrotoxicity in rats

Rutin, a flavone glycoside, has shown to have a significant beneficial kidney protection effect in drug-induced nephropathy. However, its poor solubility and low oral bioavailability have limited its pharmacological applications. This study aimed at formulating rutin-loaded bilosomes to enhance the renal protective effect of rutin for oral application. Rutin-loaded bilosomes were developed using thin-film hydration technique. The prepared formulations were characterized by entrapment efficiency percentage (EE%), vesicular size (VS) and zeta potential (ZP) measurement. The developed formula exhibited moderate EE%, ranging from 20.02 ± 2.85 to 48.57 ± 3.57%, suitable VS results that ranged from 502.1 ± 36 to 665.1 ± 45 nm and high ZP values (≤ -41.4 ± 7.27 mV). Transmission electron microscopy revealed the spherical shape of the developed bilosomes. The in-vitro release study revealed prolonged release of rutin from bilosomes, relative to free drug. F₂, prepared using the molar ratio span 60: cholesterol: sodium cholate 1:1:0.5, was selected for further investigations as it showed the highest EE%, smallest VS, optimum ZP, and persistent release profile. In-vivo studies were performed on drug-induced nephropathy in rats. Acute renal failure was induced using a single dose of potassium dichromate (PDC; 15 mg/kg; i.p). The selected formulation, F2, alleviated kidney dysfunction, oxidative stress and inflammation via decreasing MDA, TNF-α and TGF-β and increasing GSH. In addition, F2 promoted Akt/PI3K activation against PDC-induced acute renal failure. Histopathology results came in accordance with in-vivo results. Thus, bilosomes could be considered a potential delivery system for enhancing the oral delivery and kidney protection activity of rutin.