Purpose: Over the last two decades, the use of antiretroviral therapy (ART) has remarkably decreased the morbidity associated with HIV-1 infection. However, the prevalence of HIV-1-associated neurocognitive disorders (HAND) is still increasing. The blood-brain barrier (BBB) is the major impediment for penetration of antiretroviral drugs, causing therapeutics to reach only suboptimal level after systemic administration. Therefore, conventional antiretroviral drug regimens may not be sufficient to improve the treatment outcomes of HAND. To solve this problem we are developing an innovative nanoparticle-based delivery strategy which can improve the virus suppression in the CNS reservoir macrophages and microglia.
Methods: Poly(lactic-co-glycolic acid) (PLGA)-based elvitegravir nanoparticles (PLGA-EVG) were prepared by nano-precipitation technique. The physicochemical properties of PLGA-EVG were characterized using transmission electron microscopy, dynamic light scattering, and Fourier-transform infrared spectroscopy. Cellular uptake study was performed by a fluorescence microscopy and a flow cytometry. The penetration of EVG native drug /nanoformulation was determined using an in vitro BBB model and validated on mice. The efficacy of HIV-1 suppression in the CNS was assessed by exposing EVG native drug/nanoformulation in HIV-1-infected human monocyte-derived macrophages/microglia in the in vitro BBB model.
Results: We developed a PLGA-EVG nanoparticle formulation with a particle size of ~47 nm from transmission electron microscopy and zeta potential of ~ 6.74 mV from dynamic light scattering. The results showed that a maximum amount of 27% of PLGA-EVG NPs can cross the in vitro BBB after 24 hours, and also showed a significant increase in penetration of PLGA-EVG NPs compared to EVG native drug at the dose of 5 µg/mL and 10 µg/mL. In the mouse model, brain EVG concentration was found to be ~3-fold higher in PLGA-EVG NPs compared with the native drug. Most importantly, the nanoformulation were able to show an enhanced HIV-1 suppression in HIV-1-infected human monocyte-derived macrophages and monocyte-derived microglia after crossing the BBB without altering the BBB integrity.
Conclusion: In this report, we identified the stability, hemo-compatibility, and cyto-compatibility of the EVG nanoformulation. These findings from these characterizations suggest a favorable safety and the stability profile for the use as a potential CNS delivery strategy. Compared with EVG native drug, our EVG nanoformulation demonstrated an improved BBB penetration in both in vitro and in vivo systems. Overall, this is an innovative and optimized treatment strategy that has a potential for therapeutic interventions in reducing HAND.
Pallabita Chowdhury– University of Tennessee Health Science Center, memphis, Tennessee
Prashanth Nagesh– Post-doc, UTHSC, Memphis, Tennessee
Namita Sinha– Memphis, Tennessee
Hao Chen– Memphis, Tennessee
Mohammad Rahman– Memphis, Tennessee
Murali Yallapu– Assistant Professor, UTHSC, Memphis, Tennessee
Santosh Kumar– Memphis, Tennessee