흰쥐 태아 대뇌조직에서 저산소증 손상에 의한 DNA 복구 효소의 발현 변화
Expression of DNA Repairing Enzymes in the Cerebral Tissue of the Rat Fetus After Hypoxic Injury
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저산소증은 신생아의 사망률을 증가시키는 중요한 요인 중의 하나로 알려져 있다. 또한 저산소증에 의한 조직의 손상은 세포의 DNA손상과 세포자멸사 등의 복합적인 기전을 통해 나타난다. 본 연구에서는 태아기저산소증에 의한 대뇌조직의 손상과 동반된 8-hydroxyguanine glycosylase 1 (OGG1)과 apurinic/apyrimidinic endonuclease 1 (APE1)과 같은 DNA 복구 효소와 brain derived neurotrophic factor (BDNF)의 발현 변화를 밝히고자 하였다. 실험을 위해 임신 14.5일 및 15.5일된 흰쥐를 저산소 혼합가스(10% O2, 5% CO2, 85% N2)에 2시간 또는 4시간 동안 노출시킨 후 24시간이 경과된 다음 에틸에테르 마취하에 개복하여 태아를 적출하였다. 헤마톡실린-에오신염색, 면역조직화학염색, western blot 등을 실시하여 결과를 분석하였다. 실험 결과 저산소증 손상을 유발한 대뇌조직에서 caspase-3의 발현이 증가되었다. OGG1과 APE1은 임신 14.5일에 저산소증 손상을 유발한 실험군에서는 노출 시간에 비례하여 발현이 증가되었으나 임신 15.5일에 저산소증 손상을 유발한 실험군에서는 유의한 차이가 없었다. BDNF는 임신 14.5일 실험군에서는 노출시간에 비례하여 발현이 증가되었으나 임신 15.5일에 저산소증 손상을 유발한 실험군에서는 발현이 크게 감소되었다. 이러한 결과는 태아기 저산소증 손상은 신경세포들의 DNA 손상과 세포자멸사를 증가시키고 세포들은 이에대한 방어기전으로 DNA 복구 효소와 신경영양인자의 발현을 증가시킴을 제시하며, 발달 시기에 따라 방어기전의 양상이 변화함을 나타낸다.
Abstract
Hypoxia is one of the major causes of neonatal mortality. Hypoxia-induced tissue injuries are resulted from complex mechanisms such as DNA damage and apoptosis. In this study, we aimed to elucidate the changes in the expression of DNA repairing enzymes such as 8-hydroxyguanine glycosylase 1 (OGG1) and apurinic/apyrimidinic endonuclease 1 (APE1) and brain derived neurotrophic factor (BDNF) in the fetal cerebral tissue after intrauterine hypoxic injury. For this study, pregnant Sprague-Dawley rats were exposed to hypoxic gas (10% O2, 5% CO2, 85% N2) for 2 or 4 hours at postconception day 14.5 and 15.5. After 24 hours, the animals were anesthetized with ethyl ether and fetuses were obtained by laparatomy. Hematoxylin-eosin stain, immunohistochemical stain, and western blot were employed for analysis. The caspase-3 immunolabeled cells were significantly increased within the cerebral cortex after hypoxic injury. The expressions of OGG1, APE1, and BDNF were also increased in the cerebral tissue after hypoxic injury at postconception day 14.5, in a dose-dependent manner. However, the expression of BDNF was significantly decreased in the cortical tissue exposed to hypoxic injury at postconception day 15.5. These results demonstrate that fetal hypoxic injury induces apoptosis of the nerve cells and promotes the expressions of the DNA repairing enzymes and neurotrophic factors. In addition, these results suggest that protection mechanisms against hypoxic injury alter along the progression of the fetal development.
참고문헌 (31)
- Audebert M, "Alterations of the DNA repair gene OGG1 in human clear cell carcinomas of the kidney", Cancer Res, 60, pp.4740~4744 (2000)
- Berger R, "Pathophysiology of perinatal brain damage", Brain Res Rev, 30, pp.107~134 (1999)
- Bjelland S, "Mutagenicity, toxicity and repair of DNA base damage induced by oxidation", Mutat Res, 531, pp.37~80 (2003)
- Boiteux S, "The human OGG1 gene: structure, functions, and its implication in the process of carcinogenesis", Arch Biochem Biophys, 377, pp.1~8 (2000)
- Bunn HF, "Oxygen sensing and molecular adaptation to hypoxia", Physiol Rev, 76, pp.839~885 (1996)
- Chevillard S, "Mutations in OGG1, a gene involved in the repair of oxidative DNA damage, are found in human lung and kidney tumours", Oncogene, 16, pp.3083~3086 (1998)
- Chung MH, "An endonuclease activity in human polymorphonuclear neutrophils that removes 8-hydroxyguanine residues from DNA", Biochem Biophys Res Commun, 178, pp.1472~1478 (1991)
- Coyle JT, "Oxidative stress, glutamate, and neu- rodegenerative disorders", Science, 262, pp.689~695 (1993)
- Dhenaut A, "Characterization of the hOGG1 promoter and its expression during the cell cycle", Mutat Res, 461, pp.109~118 (2000)
- Joashi UC, "Poly (ADP ribose) polymerase cleavage precedes neuronal death in the hippocampus and cerebellum following injury to the developing rat forebrain", Eur J Neurosci, 11, pp.91~100 (1999)
- Kasai H, "Analysis of a form of oxidative DNA damage, 8- hydroxy-2′-deoxyguanosine, as a marker of cellular oxidative stress during carcinogenesis", Mutat Res, 387, pp.147~163 (1997)
- Kasai H, "Formation of 8-hydroxyguanine moiety in cellular DNA by agents producing oxygen radicals and evidence for its repair", Carcinogenesis, 7, pp.1849~1851 (1986)
- Kim H, "Paracrine and autocrine functions of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in brain-derived endothelial cells", J Biol Chem, 279, pp.33538~33546 (2004)
- Klungland A, "Accumulation of premutagenic DNA lesions in mice defective in removal of oxidative base damage", Proc Natl Acad Sci USA, 96, pp.13300~13305 (1999)
- Lamballe F, "trkC, a new member of the trk family of tyrosine protein kinases, is a receptor for neurotrophin-3", Cell, 66, pp.967~979 (1991)
- Le Page F, "Transcription coupled repair of 8-oxoguanine in murine cells: the ogg1 protein is required for repair in nontranscribed sequences but not in transcribed sequences", Proc Natl Acad Sci USA, 97, pp.8397~8402 (2000)
- Levine S, "Anoxic-ischemic encephalopathy in rats", Am J Pathol, 36, pp.1~17 (1960)
- McDonald JW, "Susceptibility to apoptosis is enhanced in immature cortical neurons", Brain Res, 759, pp.228~232 (1997)
- Minowa O, "Mmh", Ogg1 gene inactivation results in accumulation of 8-hydroxyguanine in mice, 2000, pp.97, 4156~4161
- Nakajima W, "Apoptosis has a prolonged role in the neurodegeneration after hypoxic ischemia in the newborn rat", J Neurosci, 20, pp.7994~8004 (2000)
- Osterod M, "Age-related and tissue-specific accumulation of oxidative DNA base damage in 7,8-dihydro-8- oxoguanine-DNA glycosylase (Ogg1) deficient mice", Carcinogenesis, 22, pp.1459~1463 (2001)
- Pulera MR, "Apoptosis in a neonatal rat model of cerebral hypoxia-ischemia", Stroke, 29, pp.2622~2630 (1998)
- Ramana CV, "Activation of apurinic", apyrimidinic endonuclease in human cells by reactive oxygen species and its correlation with their adaptive response to genotoxicity of free radicals, 1998, pp.95, 5061~5066
- Saitoh T, "Enhancement of OGG1 protein AP lyase activity by increase of APEX protein", Mutat Res, 486, pp.31~40 (2001)
- Schabitz WR, "Intraventicular brain-derived neurotrophic factor reduces infarct size after focal cerebral ischemia in rats", J Cereb Blood Flow Metab, 17, pp.500~506 (1997)
- Schabitz WR, "Intravenous brain-derived neurotrophic factor reduces infarct size and counterregulates Bax and Bcl-2 expression after temporary focal cerebral ischemia", Stroke, 31, pp.2212~2217 (2000)
- Suzuki J, "Changes in the urinary excretion level of 8-hydroxyguanine by exposure to reactive oxygen-generating substances", Free Radic Biol Med, 18, pp.431~436 (1995)
- Tsurudome Y, "Changes in levels of 8- hydroxyguanine in DNA, its repair and OGG1 mRNA in rat lungs after intratracheal administration of diesel exhaust particles", Carcinogenesis, 20, pp.1573~1576 (1999)
- Wu LL, "Urinary 8-OHdG: a marker of oxidative stress to DNA and a risk factor for cancer, atherosclerosis and diabetics", Clin Chim Acta, 339, pp.1~9 (2004)
- Yamamoto F, "Ubiquitous presence in mammalian cells of enzymatic activity specifically cleaving 8-hydroxyguanine-containing DNA", Jpn J Cancer Res, 83, pp.351~357 (1992)
- Zhang Y, "Blood-brain barrier targeting of BDNF improves motor function in rats with middle cerebral artery occlusion", Brain Res, 1111, pp.227~229 (2006)