Phagocytosis of polymeric nanoparticles aided activation of macrophages to increase atherosclerotic plaques in ApoE-/- mice

The unique physiochemical properties of nanomaterials have been widely used in drug delivery systems and diagnostic contrast agents. The safety issues of biomaterials with exceptional biocompatibility and hemo-compatibility have also received extensive attention at the nanoscale, especially in cardiovascular disease. Therefore, we conducted a study of the effects of poly (lactic-co-glycolic acid) nanoparticles (PLGA NPs) on the development of aortic atherosclerotic plaques in ApoE(-/-) mice. The particle size of PLGA NPs was 92.69 +/- 3.1 nm and the zeta potential were - 31.6 +/- 2.8 mV, with good blood compatibility. ApoE(-/-) mice were continuously injected with PLGA NPs intravenously for 4 and 12 weeks. Examination of oil red O stained aortic sinuses confirmed that the accumulation of PLGA NPs caused a significantly higher extension of atherosclerotic plaques and increasing the expression of associated inflammatory factors, such as TNF-alpha and IL-6. The combined exposure of ox-LDL and PLGA NPs accelerated the conversion of macrophages to foam cells. Our results highlight further understanding the interaction between PLGA NPs and the atherosclerotic plaques, which we should consider in future nanomaterial design and pay more attention to the process of using nano-medicines on cardiovascular diseases.

Automated summary

The study investigated the effects of PLGA NPs on the development of aortic atherosclerotic plaques in ApoE(-/-) mice, showing that the accumulation of PLGA NPs significantly increased plaque extension, expression of inflammatory factors, and accelerated macrophage conversion to foam cells. These results highlight the importance of understanding the interaction between PLGA NPs and atherosclerotic plaques for future nanomaterial design and use in cardiovascular disease treatment.