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Oxidized Low-Density Lipoprotein Inhibits THP-1-Derived Macrophage Autophagy via TET2 Down-regulation


Oxidized low-density lipoprotein (ox-LDL) is an independent risk factor of atherosclerosis. However, the mechanism underlying its pro-atherosclerosis roles has not yet been well explored. DNA demethylation modification, via DNA methyltransferases or ten-eleven-translocation (TET) family, is a crisis epigenetic regulation for various biological and pathological processes. This study aimed to investigate the effects of ox-LDL on macrophage autophagy and its potential epigenetic mechanism. Results showed that after treatment with 0, 10, 20, 40 or 80 mg/L ox-LDL for 24 h, the autophagy markers Beclin 1 and LC3 expression were obviously decreased at protein levels (P < 0.05). The mRNA and protein expression of TET2 was evidently decreased (P < 0.05). After pre-treatment with TET2 siRNA, the mRNA and protein levels of Beclin 1 and LC3 decreased compared with the 80 mg/L treatment group (P < 0.01). The mRNA and protein levels of Beclin 1 and LC3-II were up-regulated (P < 0.05) in the 5-aza-2′-deoxycytidine (a DNA methyltransferase inhibitor) of pretreatment group. Consistent with the Western blot results, cell immunofluorescence showed that the protein concentration of LC3-II decreased in the TET2 siRNA group and increased in the 5-aza-2′-deoxycytidine group. Taken together, these results showed that DNA demethylation modifications regulate ox-LDL-treated THP-1 macrophages autophagy and TET2 might be a novel regulator.

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Oxidized low-density lipoprotein


Autophagy-related gene 5




Ten-eleven translocation




Bovine serum albumin


Microtubule-associated protein 1 light chain 3




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This research program was supported by grants from the National Natural Science Foundation of China (81370378) and the construct program of the key discipline in the Hunan province.

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The authors have no conflict of interest.

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Correspondence to Dangheng Wei.

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Li, G., Peng, J., Liu, Y. et al. Oxidized Low-Density Lipoprotein Inhibits THP-1-Derived Macrophage Autophagy via TET2 Down-regulation. Lipids 50, 177–183 (2015).

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  • Plasma lipids
  • Lipoproteins
  • Atherosclerosis
  • Physiology
  • Oxidized Lipids