Background: Hyperhomocysteinemia (HHcy)-mediated dysfunction of endothelial NO system is an important mechanism for atherosclerotic pathogenesis. Dimethylarginine dimethylaminohydrolase (DDAH) is the key enzyme for degrading asymmetric dimethylarginine (ADMA), which is an endogenous inhibitor of endothelial nitric oxide (NO) synthase (eNOS). This study was designed to investigate whether the dysfunction of endothelial NO system originates from HHcy-mediated aberrant methylation modification in promotor region of DDAH2 gene.
Methods: Human umbilical vein endothelial cells (HUVECs) were cultured to the third generation and treated with homocysteine (Hcy) at different concentrations (0, 10, 30, 100, and 300 micromol/L) for 72 hours. The methylation pattern in promoter region CpG island of DDAH2 gene was analyzed by nested methylation-specific PCR (nMSP). The mRNA expression of eNOS gene and DDAH2 gene was detected by semi-quantitative RT-PCR. The activity of DDAH2 and eNOS in cells, and the concentrations of ADMA and NO in culture medium were assayed respectively.
Results: Mild increased concentration of Hcy (10 and 30 micromol/L) induced hypomethylation, while high concentration of Hcy (100 and 300 micromol/L) induced hypermethylation in the promoter CpG island of DDAH2 gene. The mRNA expression of DDAH2 increased in mild enhanced concentration of Hcy, and decreased in high concentration of Hcy correspondingly. The inhibition of DDAH2 activity, the increase of ADMA concentration, the reduction of eNOS activity and the decrease of NO production were all consistently relevant to the alteration of Hcy concentration.
Conclusion: The increased concentration of Hcy induced aberrant methylation pattern in promotor region of DDAH2 gene and the successive alterations in DDAH/ADMA/NOS/NO pathway, which showed highly relevant and dose-effect relationship. The results suggested that the dysfunction of endothelial NO system induced by HHcy could be partially originated from Hcy-mediated aberrant methylation in DDAH2 gene.
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Rev Bras Ginecol Obstet
May 2024
Universidade Federal de Minas Gerais Belo HorizonteMG Brazil Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Objective: To examine whether the promoter polymorphisms -1415G/A (rs2272592), -1151A/C (rs805304) and -449G/C (rs805305), and their haplotypes, are associated with PE compared with normotensive pregnant women, and whether they affect ADMA levels in these groups.
Methods: A total of 208 pregnant women were included in the study and classified as early-onset (N=57) or late-onset PE (N =49), and as normotensive pregnant women (N = 102).
Results: Pregnant with early-onset PE carrying the GC and GG genotypes for the -449G/C polymorphism had increased ADMA levels (P=0.
Sci Total Environ
June 2024
Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, USA; Mass Spectrometry, Proteomics and Metabolomics Core Facility, Stephenson Life Sciences Research Center, The University of Oklahoma, Norman, OK, USA. Electronic address:
Firefighters are frequently exposed to a variety of chemicals formed from smoke, which pose a risk for numerous diseases, including cancer. Comparative urine proteome profiling could significantly improve our understanding of the early detection of potential cancer biomarkers. In this study, for the first time, we conducted a comparative protein profile analysis of 20 urine samples collected from ten real-life firefighters prior to and following emergency fire-induced smoke.
View Article and Find Full Text PDFBMC Genomics
January 2024
Hunan University of Traditional Chinese Medicine, Changsha, 410208, Hunan Province, China.
Background: Nonspecific orbital inflammation (NSOI) is an idiopathic, persistent, and proliferative inflammatory condition affecting the orbit, characterized by polymorphous lymphoid infiltration. Its pathogenesis and progression have been linked to imbalances in tumor metabolic pathways, with glutamine (Gln) metabolism emerging as a critical aspect in cancer. Metabolic reprogramming is known to influence clinical outcomes in various malignancies.
View Article and Find Full Text PDFMol Biotechnol
September 2024
Department of Gastroenterology, The Affiliated People's Hospital of Ningbo University, Ningbo, China.
Bladder cancer was one of the most common carcinomas around the world. However, the mechanism of the disease still remained to be investigated. We expected to establish a prognostic survival model with 9 prognostic genes to predict overall survival (OS) in patients of bladder cancer.
View Article and Find Full Text PDFPsychol Med
October 2023
Affiliated Mental Health Center & Hangzhou Seventh People's Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Background: To identify risk genes whose expression are regulated by the reported risk variants and to explore the potential regulatory mechanism in schizophrenia (SCZ).
Methods: We systematically integrated three independent brain expression quantitative traits (eQTLs) (CommonMind, GTEx, and BrainSeq Phase 2, a total of 1039 individuals) and GWAS data (56 418 cases and 78 818 controls), with the use of transcriptome-wide association study (TWAS). Diffusion magnetic resonance imaging was utilized to quantify the integrity of white matter bundles and determine whether polygenic risk of novel genes linked to brain structure was present in patients with first-episode antipsychotic SCZ.
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