Constructing Mal‐Efferocytic Macrophage Model and Its Atherosclerotic Spheroids and Rat Model for Therapeutic Evaluation

Abstract

Efferocytosis, responsible for apoptotic cell clearance, is an essential factor against atherosclerosis. It is reported that efferocytosis is severely impaired in fibroatheroma, especially in vulnerable thin cap fibroatheroma. However, there is a shortage of studies on efferocytosis defects in cell and animal models. Here, the impacts of oxidized low density lipoprotein (ox‐LDL) and glut 1 inhibitor (STF31) on efferocytosis of macrophages are studied, and an evaluation system is constructed. Through regulating the cell ratios and stimulus, three types of atherosclerotic spheroids are fabricated, and a necrotic core emerges with surrounding apoptotic cells. Rat models present a similar phenomenon in that substantial apoptotic cells are uncleared in time in vulnerable plaque, and the model period is shortened to 7 weeks. Mechanism studies reveal that ox‐LDL, through mRNA and miRNA modulation, downregulates efferocytosis receptor (PPARγ/LXRα/MerTK), internalization molecule (SLC29a1), and upregulates the competitive receptor CD300a that inhibits efferocytosis receptor‐ligand binding process. The foam cell differentiation has also confirmed that CD36 and Lp‐PLA2 levels are significantly elevated, and macrophages present an interesting transition into prothrombic phenotype. Collectively, the atherosclerotic models featured by efferocytosis defect provide a comprehensive platform to evaluate the efficacy of medicine and biomaterials for atherosclerosis treatment.

CORM-A1 Alleviates Pro-Atherogenic Manifestations via miR-34a-5p Downregulation and an Improved Mitochondrial Function

“…Group I (control) rats fed on a laboratory chow diet; Group II (ath) was administered a single dose of vitamin D3 (600,000 IU/Kg, i.p.) at the start of the experiment and fed on an atherogenic diet (ath diet; 3% cholesterol, 0.5% cholic acid, 0.2% 6-propyl 2-thiouracil, 5% sucrose, 10% lard, and 81.3% powdered laboratory chow) for 6 weeks [29][30][31][32][33][34][35][36]; and Group III (ath + CORM-A1) and Group IV (ath + iCORM-A1) rats made atherogenic as mentioned above and were administered with CORM-A1/iCORM-A1 (2 mg/kg; i.p.) daily from the 2nd week till 6 weeks [26,37].…”

“…In order to closely relate to diet-induced pro-atherogenic manifestations, the experimental atherogenic model was developed by feeding an ath diet to SD rats [29,32,33]. Rats fed with the ath diet alone or in combination with CORM-A1/iCORM-A1 (i.p.…”