Induced expression of P-gp and BCRP transporters on brain endothelial cells using transferrin functionalized nanostructured lipid carriers: A first step of a potential strategy for the treatment of Alzheimer's disease

P-glycoprotein (P-gp) and Breast Cancer Resistance Protein (BCRP) are two transporters expressed in human neural stem/progenitor cells and at the Blood-Brain Barrier (BBB) level with decreased activity in the early stage of Alzheimer's disease (AD). Both proteins, have a protective role for the embryonic stem cells in the early developmental step, maintaining them in an undifferentiated state, and limit the access of exogenous and endogenous agents to the brain. Recently, MC111 selected from a P-gp/BCRP ligands library was investigated as multitarget strategy for AD treatment, considering its ability to induce the expression and activity of both proteins. However, MC111 clinical use could be limited for the ubiquitous physiological expression of efflux transporters and its moderate toxicity towards endothelial cells. Therefore, a selective MC111 delivery system based on nanostructured lipid carriers (NLC) functionalized with transferrin were developed. The results proved the formation of NLC with average size about 120 nm and high drug encapsulation efficiency (EE% greater than 50). In vitro studies on hCMEC/D3 cells revealed that the MC111 was selectively released by NLC at BBB level and then inducing the activity and expression of BCRP and P-gp, involved in the clearance of amyloid β peptide on brain endothelial cells.