The role of daidzein-loaded sterically stabilized solid lipid nanoparticles in therapy for cardio-cerebrovascular diseases

Daidzein is a very good candidate for treating cardio-cerebrovascular diseases, but its poor oral absorption and bioavailability limit its curative efficacy. In this work, daidzein-loaded solid lipid nanoparticles (SLNs) with PEGylated phospholipid as stabilizer were successfully prepared by hot homogenization method. SLNs showed the mean particle size 126 ± 14 nm with entrapment efficiency 82.5 ± 3.7%. In vitro release of SLNs demonstrated a sustained release manner with cumulative release over 90% within 120 h in bovine serum albumin solution (4%, w/v). The pharmacokinetic behavior showed that SLNs loading daidzein could significantly increase circulation time compared with orally administrated daidzein suspension or intravenously delivered daidzein solution. SLNs showed the better effect on cardiovascular system of the anesthetic dogs by reducing the myocardial oxygen consumption (MOC) and the coronary resistance (CR) in heart compared with oral suspension or intravenous solution. The SLNs demonstrated the best effect on cerebrovascular system by increasing cerebral blood flow (CeBF) and reducing cerebrovascular resistance (CeR) in anesthetized dogs, and the protective effect on rats with ischemia-reperfusion injury model among three formulations. These results suggested that SLNs could be a potential candidate for the treatment of cardio-cerebrovascular diseases.