Statins Combined with AAV8-TBG-LOX-1 Reduce the Vascular Lipid-driven Inflammatory Response and Inhibit Atherosclerosis

Abstract

Objective

Imbalances in liver lipid metabolism and inflammatory reactions driven by oxidized lipid deposition in blood vessels constitute the core of atherosclerosis. Insufficient degradation of cholesterol in the liver promotes oxidative modification of lipid particles and their deposition on the blood vessel wall in the peripheral circulation. The blood vessel wall engulfs and processes oxidized low-density lipoprotein (Ox-LDL) as foreign matter through pattern recognition receptors, ultimately forming lipid-encapsulated plaques. Among them, endothelial cell oxidized low density lipoprotein receptor 1 (LOX1) phagocytosis is an important link in initiating and promoting this mechanism, and hepatocytes, which are the core of lipid metabolism, are unable to process oxidized lipid particles because of the lack of receptors for the uptake of Ox-LDL. The objective of this study was to investigate whether continuous clearance of Ox-LDL through the liver metabolic pathway could provide better protection against statins therapy.

Methods

This study used statins combined with an adeno-associated virus (AAV8-TBG-LOX-1) liver-specific transfection system developed by our research group, in which statins reduced the level of LDL and promoted the ectopic expression of LOX-1 in hepatocytes to clear the continuous production of Ox-LDL. An ApoE knockout mouse model was used to study the effects of virus transfection and liver uptake and degradation of Ox-LDL. Laser confocal detection, Oil red staining and immunofluorescence staining were used to observe the effects of combined therapy on anti-atherosclerotic lesions.

Results

Laser confocal microscopy revealed that the recombinant viral vector AAV8-TBG-LOX-1 could specifically transfect hepatocytes and express LOX-1, which mediate hepatocyte phagocytosis and clearance of Ox-LDL. Oil red O staining of the aorta and valvular ring suggested that statins combined with AAV8-TBG-LOX-1 significantly inhibited atherosclerotic lesions. Tissue immunofluorescence staining suggested that statins could reduce the aggregation of macrophages in plaques and that combined therapy could further reduce the aggregation of macrophages in plaques.

Conclusion

Statins combined with AAV8-TBG-LOX-1 can alleviate the inflammatory response driven by lipids in the vascular wall, reduce the deposition of macrophages in plaques and inhibit atherosclerosis.

References

[1] LibbyP, BuringJE, BadimonL, et al. . Atherosclerosis. Nat Rev Dis Primers, 2019, 5(1): 56

[2] ZeinAA, KaurR, HusseinTOK, et al. . ABCG5/G8: a structural view to pathophysiology of the hepatobiliary cholesterol secretion. Biochem Soc Trans, 2019, 47(5): 1259-1268

[3] BriegerK, SchiavoneS, MillerFJ Jr., et al. . Reactive oxygen species: from health to disease. Swiss Med Wkly, 2012, 142: w13659

[4] RiggsKA, RohatgiA. HDL and Reverse Cholesterol Transport Biomarkers. Methodist Debakey Cardiovasc J, 2019, 15(1): 39-46

[5] YoshimotoR, FujitaY, KakinoA, et al. . The discovery of LOX-1, its ligands and clinical significance. Cardiovasc Drugs Ther, 2011, 25(5): 379-391

[6] Nègre-SalvayreA, AugéN, CamaréC, et al. . Dual signaling evoked by oxidized LDLs in vascular cells. Free Radic Biol Med, 2017, 106: 118-133

[7] ZhouF, TanY, ChenXH, et al. . Atorvastatin improves plaque stability in diabetic atherosclerosis through the RAGE pathway. Eur Rev Med Pharmacol Sci, 2018, 22(4): 1142-1149

[8] LiuM, YuY, JiangH, et al. . Simvastatin suppresses vascular inflammation and atherosclerosis in ApoE(−/−) mice by downregulating the HMGB1-RAGE axis. Acta Pharmacol Sin, 2013, 34(6): 830-836

[9] WolfD, LeyK. Immunity and Inflammation in Atherosclerosis. Circ Res, 2019, 124(2): 315-327

[10] Pedro-BotetJ, ClimentE, BenaigesD. Atherosclerosis and inflammation. New therapeutic approaches. Med Clin (Barc), 2020, 155(6): 256-262

[11] TsimikasS, WitztumJL. Measuring circulating oxidized low-density lipoprotein to evaluate coronary risk. Circulation, 2001, 103(15): 1930-1932

[12] PirilloA, NorataGD, CatapanoAL. LOX-1, OxLDL, and atherosclerosis. Mediators Inflamm, 2013, 2013: 152786

[13] ChenJ, MehtaJL, HaiderN, et al. . Role of caspases in Ox-LDL-induced apoptotic cascade in human coronary artery endothelial cells. Circ Res, 2004, 94(3): 370-376

[14] RyooS, BhuniaA, ChangF, et al. . OxLDL-dependent activation of arginase II is dependent on the LOX-1 receptor and downstream RhoA signaling. Atherosclerosis, 2011, 214(2): 279-287

RIGHTS & PERMISSIONS

Huazhong University of Science and Technology