Role of Human NADPH Quinone Oxidoreductase (NQO1) in Oxygen‐Mediated Cellular Injury and Oxidative DNA Damage in Human Pulmonary Cells

Abstract

Supplemental oxygen administration is frequently used in premature infants and adults with pulmonary insufficiency. NADPH quinone oxidoreductase (NQO1) protects cells from oxidative injury by decreasing reactive oxygen species (ROS). In this investigation, we tested the hypothesis that overexpression of NQO1 in BEAS-2B cells will mitigate cell injury and oxidative DNA damage caused by hyperoxia and that A-1221C single nucleotide polymorphism (SNP) in the NQO1 promoter would display altered susceptibility to hyperoxia-mediated toxicity. Using stable transfected BEAS-2B cells, we demonstrated that hyperoxia decreased cell viability in control cells (Ctr), but this effect was differentially mitigated in cells overexpressing NQO1 under the regulation of the CMV viral promoter, the wild-type NQO1 promoter (NQO1-NQO1), or the NQO1 promoter carrying the SNP. Interestingly, hyperoxia decreased the formation of bulky oxidative DNA adducts or 8-hydroxy-2 ′ -deoxyguanosine (8-OHdG) in Ctr cells. qPCR studies showed that mRNA levels of CYP1A1 and NQO1 were inversely related to DNA adduct formation, suggesting the protective role of these enzymes against oxidative DNA injury. In SiRNA experiments entailing the NQO1-NQO1 promoter, hyperoxia caused decreased cell viability, and this effect was potentiated in cells treated with CYP1A1 siRNA. We also found that hyperoxia caused a marked induction of DNA repair genes DDB2 and XPC in Ctr cells, supporting the idea that hyperoxia in part caused attenuation of bulky oxidative DNA lesions by enhancing nucleotide excision repair (NER) pathways. In summary, our data support a protective role for human NQO1 against oxygen-mediated toxicity and oxidative DNA lesions in human pulmonary cells, and protection against toxicity was partially lost in SNP cells. Moreover, we also demonstrate a novel protective role for CYP1A1 in the attenuation of oxidative cells and DNA injury. Future studies on the mechanisms of attenuation of oxidative injury by NQO1 should help in developing novel approaches for the prevention/treatment of ARDS in humans.

Clinical and Morphological Analysis of Efficacy of Intraperitoneal Ozone Application in Experimental Colitis: Preclinical Randomized Experimental Study

“…Несмотря на то что рассматриваемый механизм нуждается в пояснении, известно, что производные озона диссоциируют комплекс Nrf2-Keap1 за счет окисления двух групп -SH, входящих в состав Keap1, с последующим высвобождением Nrf2, который накапливается в ядре и вступает в реакцию с фактором транскрипции MAF, образуя гетеродимер, который связывается с областями ДНК, содержащими элементы антиоксидантного ответа (ARE). Это связывание вызывает активацию транскрипции более чем 200 генов антиоксидантов, таких как супероксиддисмутаза, каталаза, глутатионпероксидаза, глутатионредуктаза, глутатион-S-трансфераза, НАДФН-хиноноксидоредуктаза 1, гемеоксигеназа и система тиоредоксин (Trx)/тиоредоксинредуктаза (TrxR), действие которых препятствует образованию прооксидантных ферментов, таких как НАДФН-оксидаза, NOS, ксантиноксидаза, липоксигеназа, ЦОГ и миелопероксидаза (МПО) [20,21].…”

Mechanisms of Action of Ozone Therapy in Emerging Viral Diseases: Immunomodulatory Effects and Therapeutic Advantages With Reference to SARS-CoV-2

“…The already mentioned ARE-controlled enzymes contribute to restore the intracellular redox homeostasis altered by the inflammation-derived oxidative stress by (i) scavenging the over-produced oxidants, (ii) restoring the levels of low molecular weight antioxidants (glutathione, biliverdin), (iii) maintaining the thiol groups in their reduced form suitable for cell signaling, and (iv) promoting the reduction of ROS-generating compounds, such as quinones. In particular, NQO1 is a detoxificant enzyme that protects cells from oxidative stress by lowering ROS, protecting DNA, proteins and lipids from hyperoxia-mediated damage ( Burke et al, 2021 ).…”

Comparative analysis of the anti-inflammatory effect of ozone and 5-aminosalicylic acid in experimental colitis

“…Полагают, что противовоспалительные эффекты озона реализуются за счет активации транскрипционного фактора Nrf2, Nrf2-опосредованной Keap1-зависимой активации синтеза СОД, каталазы, глутатионпероксидазы, глутатионредуктазы, глутатион-S-трансферазы, гемоксигеназы, НАДФН-хиноноксидоредуктазы-1 и др. ферментов антиоксидантной защиты [26,27]. Кроме этого, Nrf2 подавляет активность NF-kβ и продукцию провоспалительных цитокинов за счет прямых белок-белковых взаимодействий при умеренном окислительном стрессе под воздействием озона [28].…”