Donghong Zhang1, Xiaoli Sun1, Jianlan Liu1, Xina Xie1, Wei Cui2, Yi Zhu2. 1. From the Department of Clinical Laboratory, Peking Union Medical College and Peking Union Medical College Hospital, Beijing, China (D.Z., W.C.); Department of Physiology and Pathophysiology, Key Laboratory of Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing, China (W.C.); Cardiovascular Research Center, Shantou University Medical College, Shantou, Guangdong, China (D.Z., J.L., X.X.); and Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China (Y.Z.). 2. From the Department of Clinical Laboratory, Peking Union Medical College and Peking Union Medical College Hospital, Beijing, China (D.Z., W.C.); Department of Physiology and Pathophysiology, Key Laboratory of Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing, China (W.C.); Cardiovascular Research Center, Shantou University Medical College, Shantou, Guangdong, China (D.Z., J.L., X.X.); and Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China (Y.Z.). zhuyi@tijmu.edu.cn cuiw@pumch.cn.
Abstract
OBJECTIVE: Homocysteine can accelerate the senescence of endothelial progenitor cells or endothelial cells (ECs) via telomerase inactivation and length shortening. However, the underlying mechanism is unclear. Here, we investigated whether homocysteine promotes endothelial senescence by reducing the expression and activity of human telomerase reverse transcriptase (hTERT) by DNA methylation to reduce ECs telomerase activity. APPROACH AND RESULTS: When compared with primary human umbilical vein endothelial cells grown under standard conditions, ECs with chronic homocysteine treatment showed accelerated upregulation of p16, p21, and p53, markers of cellular senescence, during 6 to 10 passages. Interestingly, homocysteine-stimulated but not angiotensin II-stimulated ECs senescence could be reversed by hypermethylation induced by folic acid or s-adenosylmethionine supplementation. Meanwhile, homocysteine promoted the shortening of telomere length specifically related to restoration of hTERT transcriptional expression and CCCTC-binding factor binding sites with hTERT promoter hypomethylation, as detected by quantitative real-time polymerase chain reaction, Western blot, methylation-specific polymerase chain reaction, and bisulfite sequencing assay. Electrophoretic mobility shift assay and chromatin immunoprecipitation results showed that homocysteine-reduced telomere activity and homocysteine-induced EC senescence might contribute to hTERT promoter demethylation by increasing CCCTC-binding factor repression and interfering in the SP1 binding to the demethylated hTERT promoter, which might relate with reduced of DNA methyltransferase 1. Furthermore, the CCCTC-binding factor-dependent mechanism of homocysteine-reduced hTERT expression via DNA demethylation was confirmed in aortic endothelia of mice with hyperhomocysteine levels. CONCLUSIONS: CCCTC-binding factor and SP1 cross talk may contribute to homocysteine-reduced hTERT DNA methylation and expression in endothelial senescence.
OBJECTIVE:Homocysteine can accelerate the senescence of endothelial progenitor cells or endothelial cells (ECs) via telomerase inactivation and length shortening. However, the underlying mechanism is unclear. Here, we investigated whether homocysteine promotes endothelial senescence by reducing the expression and activity of humantelomerase reverse transcriptase (hTERT) by DNA methylation to reduce ECs telomerase activity. APPROACH AND RESULTS: When compared with primary human umbilical vein endothelial cells grown under standard conditions, ECs with chronic homocysteine treatment showed accelerated upregulation of p16, p21, and p53, markers of cellular senescence, during 6 to 10 passages. Interestingly, homocysteine-stimulated but not angiotensin II-stimulated ECs senescence could be reversed by hypermethylation induced by folic acid or s-adenosylmethionine supplementation. Meanwhile, homocysteine promoted the shortening of telomere length specifically related to restoration of hTERT transcriptional expression and CCCTC-binding factor binding sites with hTERT promoter hypomethylation, as detected by quantitative real-time polymerase chain reaction, Western blot, methylation-specific polymerase chain reaction, and bisulfite sequencing assay. Electrophoretic mobility shift assay and chromatin immunoprecipitation results showed that homocysteine-reduced telomere activity and homocysteine-induced EC senescence might contribute to hTERT promoter demethylation by increasing CCCTC-binding factor repression and interfering in the SP1 binding to the demethylated hTERT promoter, which might relate with reduced of DNA methyltransferase 1. Furthermore, the CCCTC-binding factor-dependent mechanism of homocysteine-reduced hTERT expression via DNA demethylation was confirmed in aortic endothelia of mice with hyperhomocysteine levels. CONCLUSIONS:CCCTC-binding factor and SP1 cross talk may contribute to homocysteine-reduced hTERT DNA methylation and expression in endothelial senescence.
Authors: Kara A Michels; Jean Wactawski-Wende; James L Mills; Karen C Schliep; Audrey J Gaskins; Edwina H Yeung; Keewan Kim; Torie C Plowden; Lindsey A Sjaarda; Ellen N Chaljub; Sunni L Mumford Journal: Hum Reprod Date: 2017-08-01 Impact factor: 6.918
Authors: Irene Pusceddu; Markus Herrmann; Susanne H Kirsch; Christian Werner; Ulrich Hübner; Marion Bodis; Ulrich Laufs; Thomas Widmann; Stefan Wagenpfeil; Jürgen Geisel; Wolfgang Herrmann Journal: Eur J Nutr Date: 2016-07-05 Impact factor: 5.614
Authors: Maria Kovalska; Eva Baranovicova; Dagmar Kalenska; Anna Tomascova; Marian Adamkov; Libusa Kovalska; Jan Lehotsky Journal: Int J Mol Sci Date: 2021-05-07 Impact factor: 5.923