Targeted SLNs for management of HIV-1 associated dementia

Context: HIV-1 associated dementia (HAD) is an evolving disease in the category of neurological disorders. Objective: Nifedipine-loaded solid lipid nanoparticles (SLNs) were developed and coated with Tween 80 to facilitate enhanced brain drug delivery for the treatment of HAD. Materials and methods: SLNs were prepared using solvent injection method. Lipids consisted of tristearin, hydrogenated soya phosphatidylcholine (HSPC) (1.5: 1 w/w). Nifedipine was model drug in this study. Tween 80 (0.5% v/v) was taken as key modulator. SLNs were characterized for particle shape, size, zeta potential, entrapment efficiency, in vitro drug release, DNA fragmentation, cytotoxicity potential and in vivo studies. Results: The SLNs (plain and coated) were found to be in nanometric in size (similar to 120 nm) with more than 70% entrapment efficiency. In vitro drug release profile reflected sustained release up to 48 h. Tween 80-coated SLNs showed higher percentage of DNA fragmentation in vitro and enhanced cell viability in sulforhodamine assay (rat cortical cells) as compared to plain drug and uncoated SLNs due to facilitated uptake of SLNs and reversal of P-gp efflux by virtue of Tween 80. Biodistribution study performed on vital organs, i.e. brain, heart, liver, spleen, lungs and kidney showed increased accumulation of Tween 80-coated SLNs in the brain. Discussion and conclusion: Tween 80 enhanced localization of SLNs in the brain as compared to uncoated SLNs. This approach can be employed effectively to transport chemotherapeutics across the BBB for management of HIV-1 associated dementia and other ailments.