Antioxidants & redox signaling最新文献

Aims: High uric acid (HUA), as a pro-oxidant, plays a significant role in the pathophysiology of cardiovascular disease. Studies have indicated that elevated uric acid levels can adversely affect cardiovascular health. Nevertheless, the impact of hyperuricemia on cardiomyopathy remains uncertain. Further research is needed to elucidate the relationship between HUA and cardiomyopathy, shedding light on its potential implications for heart health. Results: We demonstrated that uricase knockout (Uox-KO) mice accelerated the development of cardiomyopathy, causing significantly impaired cardiac function and myocardial fibrosis. Meanwhile, the mitochondrial morphology was destroyed, the lipid peroxidation products increased in number and the antioxidant function was weakened. In addition, we evaluated the effects of ferrostatin-1 (Fer-1), the ferroptosis inhibitor. Myocardial damage can be reversed by the Fer-1 treatment caused by HUA combined with doxorubicin (DOX) treatment. Benzbromarone, a uric acid-lowering drug, decreases myocardial fibrosis, and ferroptosis by alleviating hyperuricemia in Uox-KO mice by DOX administration. In vitro, we observed that the activity of cardiomyocytes treated with HUA combined with DOX decreased significantly, and lipid reactive oxygen species (ROS) increased significantly. Afterward, we demonstrated that HUA can promote oxidative stress in DOX, characterized by increased mitochondrial ROS, and downregulate protein levels of glutathione peroxidase 4 (GPX4). N-acetyl-l-cysteine, an antioxidant, inhibits the process by which HUA promotes DOX-induced ferroptosis by increasing the GPX4 expression. Innovation: We verified that HUA can exacerbate myocardial damage. This has clinical implications for the treatment of cardiac damage in patients with hyperuricemia. Conclusions: Our data suggested that HUA promotes the cardiomyopathy. HUA promotes DOX-induced ferroptosis by increasing oxidative stress and downregulating GPX4. Antioxid. Redox Signal. 00, 00-00.

Significance: Potassium channels regulate the influx and efflux of K⁺ ions in various cell types that generate and propagate action potential associated with excitation, contraction, and relaxation of various cell types. Although redox active cysteines are critically important for channel activity, the redox regulation of K⁺ channels by thioredoxin (Trx) has not been systematically reviewed. Recent Advances: Redox regulation of K⁺ channel is now increasingly recognized as drug targets in the pathological condition of several cardiovascular disease processes. The role of Trx in regulation of these channels and its implication in pathological conditions have not been adequately reviewed. This review specifically focuses on the redox-regulatory role of Trx on K⁺ channel structure and function in physiological and pathophysiological conditions. Critical Issues: Ion channels, including K⁺ channel, have been implicated in the functioning of cardiomyocyte excitation-contraction coupling, vascular hyperpolarization, cellular proliferation, and neuronal stimulation in physiological and pathophysiological conditions. Although oxidation-reduction of ion channels is critically important in their function, the role of Trx, redox regulatory protein in regulation of these channels, and its implication in pathological conditions need to be studied to gain further insight into channel function. Future Directions: Future studies need to map all redox regulatory pathways in channel structure and function using novel mouse models and redox proteomic and signal transduction studies, which modulate various currents and altered excitability of relevant cells implicated in a pathological condition. We are yet at infancy of studies related to redox control of various K⁺ channels and structured and focused studies with novel animal models. Antioxid. Redox Signal. 00, 00-00.

Significance: Ferroptosis, a form of regulated cell death characterized by a large amount of lipid peroxidation-mediated membrane damage, joins the evolution of multisystem diseases, for instance, neurodegenerative diseases, chronic obstructive pulmonary disease, acute respiratory distress syndrome, osteoporosis, osteoarthritis, and so forth. Since being identified as the third gasotransmitter in living organisms, the intricate role of hydrogen sulfide (H₂S) in ferroptosis has emerged at the forefront of research. Recent Advances: Novel targets in the relevant metabolic pathways have been found, including transferrin receptor 1, cystine/glutamate antiporter, and others, coupled with the exploration of new signaling pathways, particularly the p53 signaling pathway, the nitric oxide/nuclear factor erythroid 2-related factor 2 signaling pathway, and so on. Many diseases such as emphysema and airway inflammation, myocardial diseases, endothelial dysfunction in aging arteries, and traumatic brain injury have recently been found to be alleviated directly by H₂S inhibition of ferroptosis. Safe, effective, and tolerable novel H₂S donors have been developed and have shown promising results in phase I clinical trials. Critical Issues: Complicated cross talk between the ferroptosis signaling pathway and oncogenic factors results in the risk of cancer when inhibiting ferroptosis. Notably, targeted delivery of H₂S is still a challenging task. Future Directions: Discovering more reliable and stable novel H₂S donors and achieving their targeted delivery will enable further clinical trials for diseases associated with ferroptosis inhibition by H₂S, determining their safety, efficacy, and tolerance.

Aims: The nuclear factor erythroid 2-related factor 2-Kelch-like ECH-associated protein 1 (NRF2-KEAP1) pathway plays an important role in the cellular response to oxidative stress but may also contribute to metabolic changes and drug resistance in cancer. However, despite its pervasiveness and important role, most of nuclear factor erythroid 2-related factor 2 (NRF2) target genes are defined in context-specific experiments and analysis, making it difficult to translate from one situation to another. Our study investigates whether a core NRF2 gene signature can be derived and used to represent NRF2 activation in various contexts, allowing better reproducibility and understanding of NRF2. Results: We define a core set of 14 upregulated NRF2 target genes from 7 RNA-sequencing datasets that we generated and analyzed. This NRF2 gene signature was validated using analyses of published datasets and gene sets. An NRF2 activity score based on expression of these core target genes correlates with resistance to drugs such as PX-12 and necrosulfonamide but not to paclitaxel or bardoxolone methyl. We validated these findings in our Kelch-like ECH-associated protein 1 (KEAP1) knockout cancer cell lines. Finally, our NRF2 score is prognostic for cancer survival and validated in additional independent cohorts for lung adenocarcinoma and also novel cancer types not associated with NRF2-KEAP1 mutations such as clear cell renal carcinoma, hepatocellular carcinoma, and acute myeloid leukemia. Innovation and Conclusions: These analyses define a core NRF2 gene signature that is robust, versatile, and useful for evaluating NRF2 activity and for predicting drug resistance and cancer prognosis. Using this gene signature, we uncovered novel selective drug resistance and cancer prognosis associated with NRF2 activation.

Significance: Herbal medicines have a long history of comprehensive cancer treatment through various posttranslational modifications (PTMs). Recently, emerging evidence revealed that dysregulation of reactive oxygen species (ROS) and ROS-regulated signaling pathways influence cancer initiation, growth, and progression in a paradoxical role with either low levels or increasing levels of basal ROS. However, ROS-triggered modifications of target proteins in the face of ROS-mediated signal transduction are not fully understood in the anticancer therapies of herbal medicines. In this review, we briefly introduce the PTM-dependent regulations of herbal medicines, and then focus on the current ideals that targeting ROS-dependent PTMs via antioxidant and redox signaling pathways can provide a promising strategy in herbal-based anticancer effects. Recent Advances: Advanced development in highly sensitive mass spectrometry-based techniques has helped utilize ROS-triggered protein modifications in numerous cancers. Accumulating evidence has been achieved in laboratory to extensively ascertain the biological mechanism of herbal medicines targeting ROS in cancer therapy. Two general mechanisms underlining ROS-induced cell signaling include redox state and oxidative modification of target protein, indicating a new perspective to comprehend the intricate dialogues between herbal medicines and cancer cellular contexts. Critical Issues: Complex components of herbal medicines limit the benefits of herbal-based cancer therapies. In this review, we address that ROS-dependent PTMs add a layer of proteomic complexity to the cancer through altering the protein structure, expression, function, and localization. Elaborating ROS-triggered PTMs implicated in cell signaling, apoptosis, and transcriptional regulation function, and the possible cellular signaling, has provided important information about the contribution of many ROS targeting herbal therapies in anticancer effects. Continued optimization of proteomic strategies for PTM analysis in herbal medicines is also briefly discussed. Future Directions: Rigorous evaluations of herbal medicines and proteomic strategies are necessary to explore the aberrant regulation of ROS-triggered antioxidant and redox signaling contributing to the novel protein targets and herbal-associated pharmacological issues. These efforts will eventually help develop more herbal drugs as modern therapeutic agents.

Aims: Diabetic heart damage can lead to cardiomyocyte death, which endangers human health. Baicalin (BAI) is a bioactive compound that plays an important role in cardiovascular diseases. Sentrin/SUMO-specific protease 1 (SENP1) regulates the de-small ubiquitin-like modifier (deSUMOylation) process of Sirtuin 3 (SIRT3) and plays a crucial role in regulating mitochondrial mass and preventing cell injury. Our hypothesis is that BAI regulates the deSUMOylation level of SIRT3 through SENP1 to enhance mitochondrial quality control and prevent cell death, ultimately improving diabetic cardiomyopathy (DCM). Results: The protein expression of SENP1 decreased in cardiomyocytes induced by high glucose and in db/db mice. The cardioprotective effects of BAI were eliminated by silencing endogenous SENP1, whereas overexpression of SENP1 showed similar cardioprotective effects to those of BAI. Furthermore, co-immunoprecipitation experiments showed that BAI's cardioprotective effect was due to the inhibition of the SUMOylation modification level of SIRT3 by SENP1. Inhibition of SENP1 expression resulted in an increase in SUMOylation of SIRT3. This led to increased acetylation of mitochondrial protein, accumulation of reactive oxygen species, impaired autophagy, impaired mitochondrial oxidative phosphorylation, and increased cell death. None of these changes could be reversed by BAI. Conclusion: BAI improves DCM by promoting SIRT3 deSUMOylation through SENP1, restoring mitochondrial stability, and preventing the cell death of cardiomyocytes. Innovation: This study proposes for the first time that SIRT3 SUMOylation modification is involved in the development of DCM and provides in vivo and in vitro data support that BAI inhibits cardiomyocyte ferroptosis and apoptosis in DCM through SENP1. [Figure: see text].

Significance: Peroxisome proliferator-activated receptors (PPARs) have a moderately preserved amino-terminal domain, an extremely preserved DNA-binding domain, an integral hinge region, and a distinct ligand-binding domain that are frequently encountered with the other nuclear receptors. PPAR-β/δ is among the three nuclear receptor superfamily members in the PPAR group. Recent Advances: Emerging studies provide an insight on natural compounds that have gained increasing attention as potential anticancer agents due to their ability to target multiple pathways involved in cancer development and progression. Critical Issues: Modulation of PPAR-β/δ activity has been suggested as a potential therapeutic strategy for cancer management. This review focuses on the ability of bioactive phytocompounds to impact reactive oxygen species (ROS) and redox signaling by targeting PPAR-β/δ for cancer therapy. The rise of ROS in cancer cells may play an important part in the initiation and progression of cancer. However, excessive levels of ROS stress can also be toxic to the cells and cancer cells with increased oxidative stress are likely to be more vulnerable to damage by further ROS insults induced by exogenous agents, such as phytocompounds and therapeutic agents. Therefore, redox modulation is a way to selectively kill cancer cells without causing significant toxicity to normal cells. However, use of antioxidants together with cancer drugs may risk the effect of treatment as both act through opposite mechanisms. Future Directions: It is advisable to employ more thorough and detailed methodologies to undertake mechanistic explorations of numerous phytocompounds. Moreover, conducting additional clinical studies is recommended to establish optimal dosages, efficacy, and the impact of different phytochemicals on PPAR-β/δ.