Arginine-rich Peptide Coated PLGA Nanoparticles Enhance Polymeric Delivery of Antisense HIF1α-oligonucleotide to Fully Differentiated Stiff Adipocytes

Abstract

The purpose of this study was developing the new delivery system of antisense HIF1α oligodeoxynucleotide (ASO) into the stiff adipocytes. As the adipogenesis progressed, accumulating lipid droplet in cytosol lead adipocytes membrane stiffness and difficulties in the delivery of therapeutic agents into the cytosol. Hypoxia affects a number of biological functions including angiogenesis, apoptosis, inflammation, and adipogenesis. Hypoxia-inducible transcription factor-1 alpha (HIF1α) is a major transcription factor that controls metabolic and adipogenic gene expression under hypoxia. Controlling HIFα expression can be a promising therapy for obesity treatment. The ASO was synthesized and used in a complex with polylactic-co-glycolic acid (PLGA) nanoparticles (NP). To enhance the cell-penetrating capacity, the PLGA-ASO-NP complex was coated with arginine-rich peptide (ARP) in different N:P molar ratios (PLGA-ASO-NP:ARP = 1: 1, 2: 1, 5: 1). To examine the intracellular and intranuclear delivery, these complexes were treated to fully differentiated adipocyte. The PLGA-ASO-NP/ARP improved the efficacy of ASO-delivery into stiff adipocytes by increasing the cell surface charge, determined by the zeta potential, and forming polyplexes with small particle size. The proper N:P molar ratio of PLGA-ASO-NP/ARP synthesis was 5:1 with significantly improved gene delivery efficiency and intracellular uptake in adipocytes. Furthermore, PLGA-ASO-NP/ARP was stable in serum for 8 h compared to naked ASO. These results suggest that the PLGA-ASO-NP/ARP can provide an effective and serum-stable gene-delivery system, especially for cells with a stiff cell membrane.