PubMed Central (PMC3 - NLM DTD)
Archive of life sciences journal literature at the U.S. National Institutes of Health (NIH), developed and managed by NIH's National Center for Biotechnology Information (NCBI) in the National Library of Medicine (NLM).
Antioxidants & Redox Signaling
Mostrando recursos 1 - 20 de 769
Repair of Oxidative DNA Damage and Cancer: Recent Progress in DNA Base Excision Repair - Scott, Timothy L.; Rangaswamy, Suganya; Wicker, Christina A.; Izumi, Tadahide
Significance: Reactive oxygen species (ROS) are generated by exogenous and environmental genotoxins, but also arise from mitochondria as byproducts of respiration in the body. ROS generate DNA damage of which pathological consequence, including cancer is well established. Research efforts are intense to understand the mechanism of DNA base excision repair, the primary mechanism to protect cells from genotoxicity caused by ROS. Recent Advances: In addition to the notion that oxidative DNA damage causes transformation of cells, recent studies have revealed how the mitochondrial deficiencies and ROS generation alter cell growth during the cancer transformation. Critical Issues: The emphasis of this...
The Crosstalk Between Nrf2 and AMPK Signal Pathways Is Important for the Anti-Inflammatory Effect of Berberine in LPS-Stimulated Macrophages and Endotoxin-Shocked Mice - Mo, Chunfen; Wang, Ling; Zhang, Jie; Numazawa, Satoshi; Tang, Hong; Tang, Xiaoqiang; Han, XiaoJuan; Li, Junhong; Yang, Ming; Wang, Zhe; Wei, Dandan; Xiao, Hengyi
Aims: The response of AMP-activated protein kinase (AMPK) to oxidative stress has been recently reported but the downstream signals of this response are largely unknown. Meanwhile, the upstream events for the activation of nuclear factor erythroid-2-related factor-2 (Nrf2), a critical transcriptional activator for antioxidative responses, remain unclear. In the present study, we investigated the relationship between AMPK and Nrf2 signal pathways in lipopolysaccharide (LPS)-triggered inflammatory system, in which berberine (BBR), a known AMPK activator, was used for inflammation suppression. Results and Innovation: In inflammatory macrophages, BBR attenuated LPS-induced expression of inflammatory genes (inducible nitric oxide synthase [iNOS], cyclooxygenase-2 [COX2], interleukin...
Emerging Roles of the Nucleolus in Regulating the DNA Damage Response: The Noncanonical DNA Repair Enzyme APE1/Ref-1 as a Paradigmatical Example - Antoniali, Giulia; Lirussi, Lisa; Poletto, Mattia; Tell, Gianluca
Significance: An emerging concept in DNA repair mechanisms is the evidence that some key enzymes, besides their role in the maintenance of genome stability, display also unexpected noncanonical functions associated with RNA metabolism in specific subcellular districts (e.g., nucleoli). During the evolution of these key enzymes, the acquisition of unfolded domains significantly amplified the possibility to interact with different partners and substrates, possibly explaining their phylogenetic gain of functions. Recent Advances: After nucleolar stress or DNA damage, many DNA repair proteins can freely relocalize from nucleoli to the nucleoplasm. This process may represent a surveillance mechanism to monitor the synthesis...
The Free Radical Theory of Aging Is Dead. Long Live the Damage Theory! - Gladyshev, Vadim N.
The free radical theory of aging posits that aging is caused by accumulation of damage inflicted by reactive oxygen species (ROS). Although this concept has been very useful in defining the contribution of oxidative damage to the aging process, an increasing number of studies contradict it. The idea that oxidative damage represents only one of many causes of aging also has limitations, as it does not explain causal relationships and inevitability of damage accumulation. Here, it is discussed that infidelity, heterogeneity, and imperfectness of each and every biological process may be responsible for the inevitable accumulation of by-products and other...
Protein S-Mycothiolation Functions as Redox-Switch and Thiol Protection Mechanism in Corynebacterium glutamicum Under Hypochlorite Stress - Chi, Bui Khanh; Busche, Tobias; Van Laer, Koen; Bäsell, Katrin; Becher, Dörte; Clermont, Lina; Seibold, Gerd M.; Persicke, Marcus; Kalinowski, Jörn; Messens, Joris; Antelmann, Haike
Aims: Protein S-bacillithiolation was recently discovered as important thiol protection and redox-switch mechanism in response to hypochlorite stress in Firmicutes bacteria. Here we used transcriptomics to analyze the NaOCl stress response in the mycothiol (MSH)-producing Corynebacterium glutamicum. We further applied thiol-redox proteomics and mass spectrometry (MS) to identify protein S-mycothiolation. Results: Transcriptomics revealed the strong upregulation of the disulfide stress σH regulon by NaOCl stress in C. glutamicum, including genes for the anti sigma factor (rshA), the thioredoxin and MSH pathways (trxB1, trxC, cg1375, trxB, mshC, mca, mtr) that maintain the redox balance. We identified 25 S-mycothiolated proteins in NaOCl-treated...
Noncoding RNAs in DNA Repair and Genome Integrity - Wan, Guohui; Liu, Yunhua; Han, Cecil; Zhang, Xinna; Lu, Xiongbin
Significance: The well-studied sequences in the human genome are those of protein-coding genes, which account for only 1%–2% of the total genome. However, with the advent of high-throughput transcriptome sequencing technology, we now know that about 90% of our genome is extensively transcribed and that the vast majority of them are transcribed into noncoding RNAs (ncRNAs). It is of great interest and importance to decipher the functions of these ncRNAs in humans. Recent Advances: In the last decade, it has become apparent that ncRNAs play a crucial role in regulating gene expression in normal development, in stress responses to internal...
Disarming Burkholderia pseudomallei: Structural and Functional Characterization of a Disulfide Oxidoreductase (DsbA) Required for Virulence In Vivo - Ireland, Philip M.; McMahon, Róisín M.; Marshall, Laura E.; Halili, Maria; Furlong, Emily; Tay, Stephanie; Martin, Jennifer L.; Sarkar-Tyson, Mitali
Aims: The intracellular pathogen Burkholderia pseudomallei causes the disease melioidosis, a major source of morbidity and mortality in southeast Asia and northern Australia. The need to develop novel antimicrobials is compounded by the absence of a licensed vaccine and the bacterium's resistance to multiple antibiotics. In a number of clinically relevant Gram-negative pathogens, DsbA is the primary disulfide oxidoreductase responsible for catalyzing the formation of disulfide bonds in secreted and membrane-associated proteins. In this study, a putative B. pseudomallei dsbA gene was evaluated functionally and structurally and its contribution to infection assessed. Results: Biochemical studies confirmed the dsbA gene encodes...
Human Apurinic/Apyrimidinic Endonuclease 1 - Li, Mengxia; Wilson, David M.
Significance: Human apurinic/apyrimidinic endonuclease 1 (APE1, also known as REF-1) was isolated based on its ability to cleave at AP sites in DNA or activate the DNA binding activity of certain transcription factors. We review herein topics related to this multi-functional DNA repair and stress-response protein. Recent Advances: APE1 displays homology to Escherichia coli exonuclease III and is a member of the divalent metal-dependent α/β fold-containing phosphoesterase superfamily of enzymes. APE1 has acquired distinct active site and loop elements that dictate substrate selectivity, and a unique N-terminus which at minimum imparts nuclear targeting and interaction specificity. Additional activities ascribed to...
Post-Transcriptional Regulation of DNA Damage-Responsive Gene Expression - McKay, Bruce C.
Significance: Production of proteins requires the synthesis, maturation, and export of mRNAs before their translation in the cytoplasm. Endogenous and exogenous sources of DNA damage pose a challenge to the co-ordinated regulation of gene expression, because the integrity of the DNA template can be compromised by DNA lesions. Cells recognize and respond to this DNA damage through a variety of DNA damage responses (DDRs). Failure to deal with DNA damage appropriately can lead to genomic instability and cancer. Recent Advances: The p53 tumor suppressor plays a dominant role in DDR-dependent changes in gene expression, but this transcription factor is not...
miRNA-30 Family Inhibition Protects Against Cardiac Ischemic Injury by Regulating Cystathionine-γ-Lyase Expression - Shen, Yaqi; Shen, Zhuqing; Miao, Lei; Xin, Xiaoming; Lin, Shizhou; Zhu, Yichun; Guo, Wei; Zhu, Yi Zhun
Aims: Myocardial infarction (MI) is a leading cause of death globally. MicroRNAs (miRNAs) have been identified as a novel class of MI injury regulators. Hydrogen sulfide (H2S) is a gaseous signaling molecule that regulates cardiovascular function. The purpose of this study was to explore the role of the miR-30 family in protecting against MI injury by regulating H2S production. Results: The expression of miR-30 family was upregulated in the murine MI model as well as in the primary cardiomyocyte hypoxic model. However, the cystathionine-γ-lyase (CSE) expression was significantly decreased. The overexpression of miR-30 family decreased CSE expression, reduced H2S production,...
Evolutionary Acquisition of Cysteines Determines FOXO Paralog-Specific Redox Signaling - Putker, Marrit; Vos, Harmjan R.; van Dorenmalen, Kim; de Ruiter, Hesther; Duran, Ana G.; Snel, Berend; Burgering, Boudewijn M.T.; Vermeulen, Michiel; Dansen, Tobias B.
Reduction–oxidation (redox) signaling, the translation of an oxidative intracellular environment into a cellular response, is mediated by the reversible oxidation of specific cysteine thiols. The latter can result in disulfide formation between protein hetero- or homodimers that alter protein function until the local cellular redox environment has returned to the basal state. We have previously shown that this mechanism promotes the nuclear localization and activity of the Forkhead Box O4 (FOXO4) transcription factor. Aims: In this study, we sought to investigate whether redox signaling differentially controls the human FOXO3 and FOXO4 paralogs. Results: We present evidence that FOXO3 and FOXO4...
Redox-Sensitive Structure and Function of the First Extracellular Loop of the Cell–Cell Contact Protein Claudin-1: Lessons from Molecular Structure to Animals - Dabrowski, Sebastian; Staat, Christian; Zwanziger, Denise; Sauer, Reine-Solange; Bellmann, Christian; Günther, Ramona; Krause, Eberhard; Haseloff, Reiner Fritz; Rittner, Heike; Blasig, Ingolf Ernst
The paracellular cleft within epithelia/endothelia is sealed by tight junction (TJ) proteins. Their extracellular loops (ECLs) are assumed to control paracellular permeability and are targets of pathogenes. We demonstrated that claudin-1 is crucial for paracellular tightening. Its ECL1 is essential for the sealing and contains two cysteines conserved throughout all claudins. Aims: We prove the hypothesis that this cysteine motif forms a redox-sensitive intramolecular disulfide bridge and, hence, the claudin-1-ECL1 constitutes a functional structure which is associated to ECLs of this and other TJ proteins. Results: The structure and function of claudin-1-ECL1 was elucidated by investigating sequences of this ECL...
Emerging Concepts in Hypertension - Francis, Joseph; Davisson, Robin L.
Cellular redox balance is vital in health and disease. In this Forum, we highlight the importance of reactive oxygen species (ROS) in the regulation of redox balance in different organ systems of the body and ROS contribution to the development of hypertension. The Forum examines interactions between oxidative and nitrosative stress in the brain, vasculature, and kidney, and redox effect on end-organ damage and hypertension. Furthermore, the Forum examines the role of immune cells in the modulation of hypertension. We also introduce a new role for endoplasmic reticulum stress in the induction of ROS and its possible contribution to the...
Endoplasmic Reticulum Stress and Nox-Mediated Reactive Oxygen Species Signaling in the Peripheral Vasculature: Potential Role in Hypertension - Santos, Celio X.C.; Nabeebaccus, Adam A.; Shah, Ajay M.; Camargo, Livia L.; Filho, Sidney V.; Lopes, Lucia R.
Significance: Reactive oxygen species (ROS) are produced during normal endoplasmic reticulum (ER) metabolism. There is accumulating evidence showing that under stress conditions such as ER stress, ROS production is increased via enzymes of the NADPH oxidase (Nox) family, especially via the Nox2 and Nox4 isoforms, which are involved in the regulation of blood pressure. Hypertension is a major contributor to cardiovascular and renal disease, and it has a complex pathophysiology involving the heart, kidney, brain, vessels, and immune system. ER stress activates the unfolded protein response (UPR) signaling pathway that has prosurvival and proapoptotic components. Recent Advances: Here, we summarize...