Abstract
Parkinson's disease (PD) is the second most common progressive neurodegenerative disorder associated with increased oxidative stress, the underlying vital process contributing to cell death. Tanshinone IIA (TAN) is a phytomedicine with a documented activity in treating many CNS disorders, particularly PD owing to its unique anti-inflammatory and antioxidant effect. However, its clinical utility is limited by its poor aqueous solubility, short half-life, and hence low concentration reaching targeted cells. This work aimed to develop a biocompatible chitosan-coated nanostructured lipid carriers (CS-NLCs) for effective brain delivery of TAN for PD management. The proposed nanosystem was successfully prepared using a simple melt-emulsification ultra-sonication method, optimized and characterized both in vitro and in vivo in a rotenone-induced PD rat model. The developed TAN-loaded CS-NLCs (CS-TAN-NLCs) showed good colloidal properties (size ≤ 200 nm, PDI ≤ 0.2, and ζ-potential + 20 mV) and high drug entrapment efficiency (> 97%) with sustained release profile for 24 h. Following intranasal administration, CS-TAN-NLCs succeeded to achieve a remarkable antiparkinsonian and antidepressant effect in diseased animals compared to both the uncoated TAN-NLCs and free TAN suspension as evidenced by the conducted behavioral tests and improved histopathological findings. Furthermore, biochemical evaluation of oxidative stress along with inflammatory markers, nuclear factor-kabba β (NF-Kβ) and cathepsin B further confirmed the potential of the CS-TAN-NLCs in enhancing brain delivery and hence the therapeutic effect of TAN of treatment of PD. Accordingly, CS-TAN-NLCs could be addressed as a promising nano-platform for the effective management of PD.