Epigenetic regulation of hypoxic sensing disrupts cardiorespiratory homeostasis

Autor: Guoxiang Yuan, Aaron P. Fox, Anita Pawar, Vaddi Damodara Reddy, Shakil A. Khan, Ganesh K. Kumar, Gregg L. Semenza, Jayasri Nanduri, Ning Wang, Ying-Jie Peng, Xin Zhang, Brian J. Kinsman, Vladislav V. Makarenko, Lucy A. Godley, Nanduri R. Prabhakar
Rok vydání: 2012
Předmět:
Zdroj: Proceedings of the National Academy of Sciences. 109:2515-2520
ISSN: 1091-6490
0027-8424
DOI: 10.1073/pnas.1120600109
Popis: Recurrent apnea with intermittent hypoxia is a major clinical problem in preterm infants. Recent studies, although limited, showed that adults who were born preterm exhibit increased incidence of sleep-disordered breathing and hypertension, suggesting that apnea of prematurity predisposes to autonomic dysfunction in adulthood. Here, we demonstrate that adult rats that were exposed to intermittent hypoxia as neonates exhibit exaggerated responses to hypoxia by the carotid body and adrenal chromaffin cells, which regulate cardio-respiratory function, resulting in irregular breathing with apneas and hypertension. The enhanced hypoxic sensitivity was associated with elevated oxidative stress, decreased expression of genes encoding antioxidant enzymes, and increased expression of pro-oxidant enzymes. Decreased expression of the Sod2 gene, which encodes the antioxidant enzyme superoxide dismutase 2, was associated with DNA hypermethylation of a single CpG dinucleotide close to the transcription start site. Treating neonatal rats with decitabine, an inhibitor of DNA methylation, during intermittent hypoxia exposure prevented oxidative stress, enhanced hypoxic sensitivity, and autonomic dysfunction. These findings implicate a hitherto uncharacterized role for DNA methylation in mediating neonatal programming of hypoxic sensitivity and the ensuing autonomic dysfunction in adulthood.
Databáze: OpenAIRE