Chang-Sheng Ma,1,2,* Ya-Ping Ma,1,3,* Bo Han,1,2,* Wan-Li Duan,1 Shu-Chen Meng,1 Min Bai,1 Hao Dong,1 Li-Ying Zhang,1 Meng-Yuan Duan,1,2 Jing Liu,1 Ai-Jun Deng,2 Mao-Tao He1,2 

1Department of Basic Medical Sciences, Shandong Second Medical University, Weifang, Shandong, People’s Republic of China; 2Department of Ophthalmology, Affiliated Hospital of Shandong Second Medical University, Weifang, People’s Republic of China; 3Department of Pathology, The 942Hospital of the People’s Liberation Army Joint Logistic Support Force, Yinchuan, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Mao-Tao He, Department of Basic Medical Sciences, Shandong Second Medical University, Weifang, Shandong, People’s Republic of China, Tel +86-18209617186, Fax +86-0536-3081201, Email hemaotao@sdsmu.edu.cn Ai-Jun Deng, Department of Ophthalmology, Affiliated Hospital of Shandong Second Medical University, Weifang, People’s Republic of China, Email dengaijun@hotmail.com

Purpose: Ischemic stroke is a refractory disease wherein the reperfusion injury caused by sudden restoration of blood supply is the main cause of increased mortality and disability. However, current therapeutic strategies for the inflammatory response induced by cerebral ischemia-reperfusion (I/R) injury are unsatisfactory. This study aimed to develop a functional nanoparticle (MM/ANPs) comprising apelin-13 (APNs) encapsulated in macrophage membranes (MM) modified with distearoyl phosphatidylethanolamine-polyethylene glycol-RVG29 (DSPE-PEG-RVG29) to achieve targeted therapy against ischemic stroke.
Methods: MM were extracted from RAW264.7. PLGA was dissolved in dichloromethane, while Apelin-13 was dissolved in water, and CY5.5 was dissolved in dichloromethane. The precipitate was washed twice with ultrapure water and then resuspended in 10 mL to obtain an aqueous solution of PLGA nanoparticles. Subsequently, the cell membrane was evenly dispersed homogeneously and mixed with PLGA-COOH at a mass ratio of 1:1 for the hybrid ultrasound. DSPE-PEG-RVG29 was added and incubated for 1 h to obtain MM/ANPs.
Results: In this study, we developed a functional nanoparticle delivery system (MM/ANPs) that utilizes macrophage membranes coated with DSPE-PEG-RVG29 peptide to efficiently deliver Apelin-13 to inflammatory areas using ischemic stroke therapy. MM/ANPs effectively cross the blood-brain barrier and selectively accumulate in ischemic and inflamed areas. In a mouse I/R injury model, these nanoparticles significantly improved neurological scores and reduced infarct volume. Apelin-13 is gradually released from the MM/ANPs, inhibiting NLRP3 inflammasome assembly by enhancing sirtuin 3 (SIRT3) activity, which suppresses the inflammatory response and pyroptosis. The positive regulation of SIRT3 further inhibits the NLRP3-mediated inflammation, showing the clinical potential of these nanoparticles for ischemic stroke treatment. The biocompatibility and safety of MM/ANPs were confirmed through in vitro cytotoxicity tests, blood-brain barrier permeability tests, biosafety evaluations, and blood compatibility studies.
Conclusion: MM/ANPs offer a highly promising approach to achieve ischemic stroke-targeted therapy inhibiting NLRP3 inflammasome-mediated pyroptosis.

Keywords: apelin-13, cerebral ischemia-reperfusion injury, macrophage membrane, ischemic stroke therapy, pyroptosis