Pub Date : 2024-06-01Epub Date: 2024-05-28DOI: 10.3390/oxygen4020013
Sydney L Olson, Razeen J Akbar, Adrianna Gorniak, Laura I Fuhr, Mostafa A Borahay
Uterine fibroids are the most common tumors in females affecting up to 70% of women world-wide, yet targeted therapeutic options are limited. Oxidative stress has recently surfaced as a key driver of fibroid pathogenesis and provides insights into hypoxia-induced cell transformation, extracellular matrix pathophysiology, hypoxic cell signaling cascades, and uterine biology. Hypoxia drives fibroid tumorigenesis through (1) promoting myometrial stem cell proliferation, (2) causing DNA damage propelling transformation of stem cells to tumor initiating cells, and (3) driving excess extracellular matrix (ECM) production. Common fibroid-associated DNA mutations include MED12 mutations, HMGA2 overexpression, and Fumarate hydratase loss of function. Evidence suggests an interaction between hypoxia signaling and these mutations. Fibroid development and growth are promoted by hypoxia-triggered cell signaling via various pathways including HIF-1, TGFβ, and Wnt/β-catenin. Fibroid-associated hypoxia persists due to antioxidant imbalance, ECM accumulation, and growth beyond adequate vascular supply. Current clinically available fibroid treatments do not take advantage of hypoxia-targeting therapies. Growing pre-clinical and clinical studies identify ROS inhibitors, anti-HIF-1 agents, Wnt/β-catenin inhibition, and TGFβ cascade inhibitors as agents that may reduce fibroid development and growth through targeting hypoxia.
{"title":"Hypoxia in uterine fibroids: role in pathobiology and therapeutic opportunities.","authors":"Sydney L Olson, Razeen J Akbar, Adrianna Gorniak, Laura I Fuhr, Mostafa A Borahay","doi":"10.3390/oxygen4020013","DOIUrl":"10.3390/oxygen4020013","url":null,"abstract":"<p><p>Uterine fibroids are the most common tumors in females affecting up to 70% of women world-wide, yet targeted therapeutic options are limited. Oxidative stress has recently surfaced as a key driver of fibroid pathogenesis and provides insights into hypoxia-induced cell transformation, extracellular matrix pathophysiology, hypoxic cell signaling cascades, and uterine biology. Hypoxia drives fibroid tumorigenesis through (1) promoting myometrial stem cell proliferation, (2) causing DNA damage propelling transformation of stem cells to tumor initiating cells, and (3) driving excess extracellular matrix (ECM) production. Common fibroid-associated DNA mutations include MED12 mutations, HMGA2 overexpression, and Fumarate hydratase loss of function. Evidence suggests an interaction between hypoxia signaling and these mutations. Fibroid development and growth are promoted by hypoxia-triggered cell signaling via various pathways including HIF-1, TGFβ, and Wnt/β-catenin. Fibroid-associated hypoxia persists due to antioxidant imbalance, ECM accumulation, and growth beyond adequate vascular supply. Current clinically available fibroid treatments do not take advantage of hypoxia-targeting therapies. Growing pre-clinical and clinical studies identify ROS inhibitors, anti-HIF-1 agents, Wnt/β-catenin inhibition, and TGFβ cascade inhibitors as agents that may reduce fibroid development and growth through targeting hypoxia.</p>","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11218552/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141494487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mitochondrial dysfunction significantly contributes to the pathogenesis and progression of chronic obstructive pulmonary disease (COPD). To treat mitochondrial dysfunction in COPD, novel drug delivery systems (DDS) are needed. In this review, we provide a brief overview of the current understanding of the factors in COPD and highlight the trends in novel nanocarriers/nanoparticles for targeting mitochondrial dysfunction. These drug-encapsulated nanoparticles are still in the early stages of clinical application but represent the most promising system for COPD therapy.
{"title":"Mitochondrial Dysfunction and Nanocarrier-Based Treatments in Chronic Obstructive Pulmonary Disease (COPD)","authors":"Kiyoshi Sato, Hiroyoshi Kawakami","doi":"10.3390/oxygen3040026","DOIUrl":"https://doi.org/10.3390/oxygen3040026","url":null,"abstract":"Mitochondrial dysfunction significantly contributes to the pathogenesis and progression of chronic obstructive pulmonary disease (COPD). To treat mitochondrial dysfunction in COPD, novel drug delivery systems (DDS) are needed. In this review, we provide a brief overview of the current understanding of the factors in COPD and highlight the trends in novel nanocarriers/nanoparticles for targeting mitochondrial dysfunction. These drug-encapsulated nanoparticles are still in the early stages of clinical application but represent the most promising system for COPD therapy.","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134900894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Atmospheric electric fields (AEFs) have recently been proposed to link to biogeochemical processes below the Earth’s surface by means of a charge separation. Despite the potential importance of such a process, up to now we almost completely lack the relevant measurements. Here, we extend the database with 2 months of concurrent soil redox and atmospheric electric field measurements. It appears that the changes that occur in the order of days in soil redox are at periods anticorrelated with the logarithm of the positive values of the AEF. However, weather conditions might be driving the anticorrelation rather than a direct link, as the synoptic weather conditions appear to influence soil redox. Soil redox does not respond to changes in the AEF that are of shorter duration, either minutes or several hours, except in some cases of very negative AEFs or very high field strengths in the presence of moderate rainfall. In such a case, the variation in soil redox could be associated with a mechanism that transfers charge to the ground or brings ions towards the ground’s surface. To reach firmer conclusions on the effect of the AEF on soil redox, we need to extend the range of collocated soil redox and AEF measurements so that they cover at least one year.
{"title":"The Influence of the Atmospheric Electric Field on Soil Redox Potential","authors":"Konstantinos Kourtidis, Michel Vorenhout","doi":"10.3390/oxygen3040025","DOIUrl":"https://doi.org/10.3390/oxygen3040025","url":null,"abstract":"Atmospheric electric fields (AEFs) have recently been proposed to link to biogeochemical processes below the Earth’s surface by means of a charge separation. Despite the potential importance of such a process, up to now we almost completely lack the relevant measurements. Here, we extend the database with 2 months of concurrent soil redox and atmospheric electric field measurements. It appears that the changes that occur in the order of days in soil redox are at periods anticorrelated with the logarithm of the positive values of the AEF. However, weather conditions might be driving the anticorrelation rather than a direct link, as the synoptic weather conditions appear to influence soil redox. Soil redox does not respond to changes in the AEF that are of shorter duration, either minutes or several hours, except in some cases of very negative AEFs or very high field strengths in the presence of moderate rainfall. In such a case, the variation in soil redox could be associated with a mechanism that transfers charge to the ground or brings ions towards the ground’s surface. To reach firmer conclusions on the effect of the AEF on soil redox, we need to extend the range of collocated soil redox and AEF measurements so that they cover at least one year.","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135730341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ekaterina A. Yurchenko, Olga O. Khmel, Liliana E. Nesterenko, Dmitry L. Aminin
Marine fungal metabolites often exhibit antioxidant activity, but their effects on the Keap1/Nrf2 cellular system are rarely studied, possibly due to insufficient isolated amounts. In this work, we used a bioinformatics approach to evaluate the ability of some promising cytoprotective compounds to bind Kelch domain of Keap1 protein, and thus inhibit its interaction with Nrf2. The molecular docking data suggested that gliorosein, niveoglaucin A, 6-hydroxy-N-acetyl-β-oxotryptamine, 4-hydroxyscytalone and 4-hydroxy-6-dehydroxyscytalone can form the hydrogen building with Arg415 or Arg483 amino acid residues of P1-P2 sub-pockets in the Nrf2 binding site of Keap1′s Kelch domain. These positions of the small molecules in the Kelch domain of Keap1 can inhibit the interaction of Keap1 with Nrf2 and enhance the nuclear translocation of Nrf2 from cytosol that can result in overexpression of relative genes. This assumption, based on virtual screening of a number of low molecular weight metabolites of marine fungi, makes them promising for further studies.
海洋真菌代谢产物通常具有抗氧化活性，但它们对Keap1/Nrf2细胞系统的影响很少被研究，可能是由于分离量不足。在这项工作中，我们使用生物信息学方法来评估一些有希望的细胞保护化合物结合Keap1蛋白的Kelch结构域的能力，从而抑制其与Nrf2的相互作用。分子对接数据表明，glioroosein、niveoglaucin A、6-羟基- n -乙酰基-β-氧色胺、4-羟基-6-去羟基辛塔酮和4-羟基-6-去羟基辛塔酮可与Keap1 Kelch结构域Nrf2结合位点P1-P2亚袋中的Arg415或Arg483氨基酸残基形成氢结构。Keap1 Kelch结构域的这些小分子位置可以抑制Keap1与Nrf2的相互作用，增强Nrf2从细胞质中的核易位，从而导致相关基因的过表达。这一假设是基于对许多海洋真菌低分子量代谢物的虚拟筛选，使它们有进一步研究的希望。
{"title":"The Kelch/Nrf2 Antioxidant System as a Target for Some Marine Fungal Metabolites","authors":"Ekaterina A. Yurchenko, Olga O. Khmel, Liliana E. Nesterenko, Dmitry L. Aminin","doi":"10.3390/oxygen3040024","DOIUrl":"https://doi.org/10.3390/oxygen3040024","url":null,"abstract":"Marine fungal metabolites often exhibit antioxidant activity, but their effects on the Keap1/Nrf2 cellular system are rarely studied, possibly due to insufficient isolated amounts. In this work, we used a bioinformatics approach to evaluate the ability of some promising cytoprotective compounds to bind Kelch domain of Keap1 protein, and thus inhibit its interaction with Nrf2. The molecular docking data suggested that gliorosein, niveoglaucin A, 6-hydroxy-N-acetyl-β-oxotryptamine, 4-hydroxyscytalone and 4-hydroxy-6-dehydroxyscytalone can form the hydrogen building with Arg415 or Arg483 amino acid residues of P1-P2 sub-pockets in the Nrf2 binding site of Keap1′s Kelch domain. These positions of the small molecules in the Kelch domain of Keap1 can inhibit the interaction of Keap1 with Nrf2 and enhance the nuclear translocation of Nrf2 from cytosol that can result in overexpression of relative genes. This assumption, based on virtual screening of a number of low molecular weight metabolites of marine fungi, makes them promising for further studies.","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135386723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniel Rojas-Valverde, Aldo A. Vasquez-Bonilla, Rafael Timón, Joan M. Feliu-Ilvonen, Ismael Martínez-Guardado, Guillermo Olcina
Background: Emerging evidence suggests that the outcomes of hypoxia training may be influenced by various factors, contingent upon the chosen method, such as chamber, tent, or mask. This study aimed to examine how different training methods influence the effects of Repeated Sprints in Hypoxia (RSH) training. Methods: Sixteen well-trained cyclists were divided into two groups, experimental (tent; n = 8) and control (mask; n = 8), and carried out eight RSH sessions for four weeks. Training sessions consisted of three bouts of high-intensity sprints using a cycle ergometer. The indoor ambient conditions (CO2, temperature, and humidity), performance variables (power and relative power output), arterial oxygen saturation, local muscle oxygen of vastus lateralis, heart rate, core temperature, and physiological variables (perception of effort) were measured in each training session. Results: The experimental group reported significantly higher CO2 (p < 0.001 ES = 0.784), humidity levels (p < 0.001 ES = 0.750), thermal discomfort (p = 0.003 ES = 0.266), dehydration (p 0.025 ES = 0.097), heart rate (p = 0.017 ES = 0.113), and lower muscle oxygen amplification (p = 0.002 ES = 0.181) than the control group. Conclusion: According to the responses observed, interval training performed under hypoxic conditions inside a chamber induces a more severe physiological response.
背景:新出现的证据表明，缺氧训练的结果可能受到各种因素的影响，取决于所选择的方法，如室内、帐篷或面罩。本研究旨在研究不同的训练方法如何影响在低氧(RSH)训练中重复冲刺的效果。方法:16名训练有素的自行车运动员分为两组，实验组(帐篷组;N = 8)和对照组(口罩;n = 8)，并进行8次RSH疗程，为期四周。训练包括三次高强度的冲刺，使用自行车计力器。在每次训练中测量室内环境条件(CO2、温度和湿度)、性能变量(功率和相对功率输出)、动脉血氧饱和度、股外侧局部肌氧、心率、核心温度和生理变量(努力感)。结果:实验组的CO2 (p <0.001 ES = 0.784)，湿度水平(p <0.001 ES = 0.750)、热不适(p = 0.003 ES = 0.266)、脱水(p = 0.025 ES = 0.097)、心率(p = 0.017 ES = 0.113)、肌氧扩增(p = 0.002 ES = 0.181)均低于对照组。结论:根据观察到的反应，在室内低氧条件下进行间歇训练会引起更严重的生理反应。
{"title":"Exploring the Impact of Training Methods on Repeated Sprints in Hypoxia Training Effects","authors":"Daniel Rojas-Valverde, Aldo A. Vasquez-Bonilla, Rafael Timón, Joan M. Feliu-Ilvonen, Ismael Martínez-Guardado, Guillermo Olcina","doi":"10.3390/oxygen3030023","DOIUrl":"https://doi.org/10.3390/oxygen3030023","url":null,"abstract":"Background: Emerging evidence suggests that the outcomes of hypoxia training may be influenced by various factors, contingent upon the chosen method, such as chamber, tent, or mask. This study aimed to examine how different training methods influence the effects of Repeated Sprints in Hypoxia (RSH) training. Methods: Sixteen well-trained cyclists were divided into two groups, experimental (tent; n = 8) and control (mask; n = 8), and carried out eight RSH sessions for four weeks. Training sessions consisted of three bouts of high-intensity sprints using a cycle ergometer. The indoor ambient conditions (CO2, temperature, and humidity), performance variables (power and relative power output), arterial oxygen saturation, local muscle oxygen of vastus lateralis, heart rate, core temperature, and physiological variables (perception of effort) were measured in each training session. Results: The experimental group reported significantly higher CO2 (p < 0.001 ES = 0.784), humidity levels (p < 0.001 ES = 0.750), thermal discomfort (p = 0.003 ES = 0.266), dehydration (p 0.025 ES = 0.097), heart rate (p = 0.017 ES = 0.113), and lower muscle oxygen amplification (p = 0.002 ES = 0.181) than the control group. Conclusion: According to the responses observed, interval training performed under hypoxic conditions inside a chamber induces a more severe physiological response.","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136362212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria Rosaria Miranda, Vincenzo Vestuto, O. Moltedo, M. Manfra, P. Campiglia, G. Pepe
The pathogenesis of various gastrointestinal (GI) disorders, including gastritis, ulcers, inflammatory bowel disease (IBD) and cancer, can be linked to oxidative stress. It is known that reactive species carry out a crucial role in the genesis and progression of these pathologies; however, the contribution of ionic channels in their development is still under discussion. The function of ion channels in the gastrointestinal tract influences a variety of cellular processes. Acid-base balance, mucus layer, microbiota and mucosal blood flow are only some of the essential features for maintaining the mucosal integrity of the cellular barrier in the intestine, allowing for the preservation of proper permeability and ensuring tissue homeostasis. As the functional modulation of several ion channels is altered during oxidative stress conditions associated with gastrointestinal inflammation, this review focuses on contributing new insight into the roles of and the relationship between ion channels and oxidative stress in GI diseases. The association between ion channels and oxidative stress conditions could be used in diagnostics and the development of new pharmacological treatments for major gastrointestinal diseases.
{"title":"The Ion Channels Involved in Oxidative Stress-Related Gastrointestinal Diseases","authors":"Maria Rosaria Miranda, Vincenzo Vestuto, O. Moltedo, M. Manfra, P. Campiglia, G. Pepe","doi":"10.3390/oxygen3030022","DOIUrl":"https://doi.org/10.3390/oxygen3030022","url":null,"abstract":"The pathogenesis of various gastrointestinal (GI) disorders, including gastritis, ulcers, inflammatory bowel disease (IBD) and cancer, can be linked to oxidative stress. It is known that reactive species carry out a crucial role in the genesis and progression of these pathologies; however, the contribution of ionic channels in their development is still under discussion. The function of ion channels in the gastrointestinal tract influences a variety of cellular processes. Acid-base balance, mucus layer, microbiota and mucosal blood flow are only some of the essential features for maintaining the mucosal integrity of the cellular barrier in the intestine, allowing for the preservation of proper permeability and ensuring tissue homeostasis. As the functional modulation of several ion channels is altered during oxidative stress conditions associated with gastrointestinal inflammation, this review focuses on contributing new insight into the roles of and the relationship between ion channels and oxidative stress in GI diseases. The association between ion channels and oxidative stress conditions could be used in diagnostics and the development of new pharmacological treatments for major gastrointestinal diseases.","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41423202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Molecular mechanisms based on photo-physical processes involving dietary carotenoids, their radicals, and the role of oxygen are discussed and used to suggest explanations of the poorly understood and often contradictory results related to mainly skin and vision. Differing and conflicting efficiencies of singlet oxygen reactions with carotenoids of biological importance are discussed in environments from ‘simple’ organic solvents to single He La cells. A range of free radical reactions with carotenoids, and the corresponding radicals of the carotenoids themselves, are compared and used to explain the switch from beneficial to deleterious processes involving dietary carotenoids and to unravel their differing functions; of particular interest is a possible role for vitamin C.
{"title":"Photochemical and Photophysical Properties of Carotenoids and Reactive Oxygen Species: Contradictions Relating to Skin and Vision","authors":"Fritz Boehm, R. Edge, T. Truscott","doi":"10.3390/oxygen3030021","DOIUrl":"https://doi.org/10.3390/oxygen3030021","url":null,"abstract":"Molecular mechanisms based on photo-physical processes involving dietary carotenoids, their radicals, and the role of oxygen are discussed and used to suggest explanations of the poorly understood and often contradictory results related to mainly skin and vision. Differing and conflicting efficiencies of singlet oxygen reactions with carotenoids of biological importance are discussed in environments from ‘simple’ organic solvents to single He La cells. A range of free radical reactions with carotenoids, and the corresponding radicals of the carotenoids themselves, are compared and used to explain the switch from beneficial to deleterious processes involving dietary carotenoids and to unravel their differing functions; of particular interest is a possible role for vitamin C.","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49430221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chronic kidney disease (CKD) affects 10% of the population. Fibrosis is the hallmark of CKD, which is marked by the deposit of extracellular matrix (ECM). This response is the final outcome of an unbalanced reaction to inflammation and wound healing and can be induced by a variety of insults, including hypoxia. Vascular damage results in an impaired tissue oxygen supply, inducing immune cell infiltration, tubule injury and the activation of ECM-secreting myofibroblasts. In turn, tubulointerstitial fibrosis development worsens oxygen diffusion. Hypoxia-inducible factor (HIF) is the primary transcriptional regulator of hypoxia-associated responses, such as oxidative stress and metabolic reprogramming, triggering a proinflammatory and profibrotic landscape. In this review, we discuss hypoxia-driven reprogramming in CKD as well as potential therapeutic approaches to target chronic hypoxia.
{"title":"Hypoxia-Driven Responses in Chronic Kidney Disease","authors":"V. Miguel, Alba Rojo","doi":"10.3390/oxygen3030020","DOIUrl":"https://doi.org/10.3390/oxygen3030020","url":null,"abstract":"Chronic kidney disease (CKD) affects 10% of the population. Fibrosis is the hallmark of CKD, which is marked by the deposit of extracellular matrix (ECM). This response is the final outcome of an unbalanced reaction to inflammation and wound healing and can be induced by a variety of insults, including hypoxia. Vascular damage results in an impaired tissue oxygen supply, inducing immune cell infiltration, tubule injury and the activation of ECM-secreting myofibroblasts. In turn, tubulointerstitial fibrosis development worsens oxygen diffusion. Hypoxia-inducible factor (HIF) is the primary transcriptional regulator of hypoxia-associated responses, such as oxidative stress and metabolic reprogramming, triggering a proinflammatory and profibrotic landscape. In this review, we discuss hypoxia-driven reprogramming in CKD as well as potential therapeutic approaches to target chronic hypoxia.","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43682635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Atmospheric oxygen is produced and consumed by life on Earth, and the ozone layer protects life on Earth from harmful solar UV radiation. The research on oxygen in the Earth system is of interest to many different geoscientific communities, from paleoclimatology to aeronomy. I provide a brief overview of the research activities and their motivations. In situ measurements and remote sensing of atmospheric oxygen are described. The global evolution, distribution, and trends of atmospheric oxygen are discussed.
{"title":"Oxygen in the Earth System","authors":"K. Hocke","doi":"10.3390/oxygen3030019","DOIUrl":"https://doi.org/10.3390/oxygen3030019","url":null,"abstract":"Atmospheric oxygen is produced and consumed by life on Earth, and the ozone layer protects life on Earth from harmful solar UV radiation. The research on oxygen in the Earth system is of interest to many different geoscientific communities, from paleoclimatology to aeronomy. I provide a brief overview of the research activities and their motivations. In situ measurements and remote sensing of atmospheric oxygen are described. The global evolution, distribution, and trends of atmospheric oxygen are discussed.","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43416817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Palaiogiannis, Theodoros G. Chatzimitakos, V. Athanasiadis, Eleni Bozinou, D. Makris, S. Lalas
The aim of this study was to evaluate the efficiency of successive extraction (using solvents of increasing polarity, namely hexane, ethyl acetate, acetone, ethanol, and water) of polyphenols from Cistus creticus L. The results were compared with the ones obtained from a single-solvent extraction (ethanol, water, and 50% ethanol: water). According to the results, each solvent used for extraction had a significant effect on the yield of extracted polyphenols and the antioxidant activity of the extracts. The highest extraction yield for successive extraction was achieved with ethanol (95.33 mg GAE/g), whereas a comparable amount could also be extracted with 50% ethanol: water mixture single-solvent extraction (96.51 mg GAE/g). The ethanolic and aqueous extracts had the highest antioxidant activity as indicated by their lowest IC50 values in the DPPH assay, specifically 350.99 μg/mL for ethanolic extract of successive extraction and 341.18 μg/mL for 50% ethanol: water mixture of single-solvent extraction, followed by the extract produced using acetone. However, the acetone extract contained more flavonoids than the other two extracts up to 28.03 mg QE/g. The results obtained were in line with those for the single-solvent extraction. It is concluded that using a range of solvents in succession is a more efficient way of extracting higher amounts of antioxidant compounds with varying antioxidant activity.
{"title":"Successive Solvent Extraction of Polyphenols and Flavonoids from Cistus creticus L. Leaves","authors":"D. Palaiogiannis, Theodoros G. Chatzimitakos, V. Athanasiadis, Eleni Bozinou, D. Makris, S. Lalas","doi":"10.3390/oxygen3030018","DOIUrl":"https://doi.org/10.3390/oxygen3030018","url":null,"abstract":"The aim of this study was to evaluate the efficiency of successive extraction (using solvents of increasing polarity, namely hexane, ethyl acetate, acetone, ethanol, and water) of polyphenols from Cistus creticus L. The results were compared with the ones obtained from a single-solvent extraction (ethanol, water, and 50% ethanol: water). According to the results, each solvent used for extraction had a significant effect on the yield of extracted polyphenols and the antioxidant activity of the extracts. The highest extraction yield for successive extraction was achieved with ethanol (95.33 mg GAE/g), whereas a comparable amount could also be extracted with 50% ethanol: water mixture single-solvent extraction (96.51 mg GAE/g). The ethanolic and aqueous extracts had the highest antioxidant activity as indicated by their lowest IC50 values in the DPPH assay, specifically 350.99 μg/mL for ethanolic extract of successive extraction and 341.18 μg/mL for 50% ethanol: water mixture of single-solvent extraction, followed by the extract produced using acetone. However, the acetone extract contained more flavonoids than the other two extracts up to 28.03 mg QE/g. The results obtained were in line with those for the single-solvent extraction. It is concluded that using a range of solvents in succession is a more efficient way of extracting higher amounts of antioxidant compounds with varying antioxidant activity.","PeriodicalId":74387,"journal":{"name":"Oxygen (Basel, Switzerland)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47471149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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