Enhancing the efficacy and bioavailability of isoxsuprine for the treatment of cardiotoxicity: in vitro and in vivo studies

Isoxsuprine (ISX) is a blood flow-improving beta-adrenergic agonist that provides cardiotoxicity protection. However, the limited effectiveness of ISX can be attributed to a short half-life and low bioavailability. The focus of this study was to create ISX-loaded transbilosomes (ILT), improving sustainability, permeability, bioavailability, safety, and ISX therapeutic efficacy as a safe option for managing cardiotoxicity. Different ILT formulations were developed using design expert software. Additionally, a rat model of cardiotoxicity was used to conduct an <i>in vivo</i> study to assess its bioavailability, safety, and efficacy. An optimised ILT formulation was identified, consisting of 275 mg phospholipid, 20 mg cholesterol, 25 mg Span 60, and 20 mg sodium deoxycholate. This formulation achieved a release rate of 29.22%, a permeation rate of 95.66%, and resulted in a 3.55-fold increase in bioavailability. Compared to the disease group, the optimised ILT significantly reduced mortality and levels of troponin-1, LDH, CK-MB, and MDA by 23.89%, 99.03%, 94.77%, 96.77%, and 96.57%, respectively. Furthermore, it enhanced the GSH, SOD, and CAT by 3.69-fold, 3.54-fold, and 3.57-fold, respectively. These findings suggest that nasal ILT could be an innovative avenue to consider for treating cardiotoxicity.