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Li W, Zhang Y, Wang Q, Wang Y, Fan Y, Shang E, Jiang S, Duan J. 6-Gingerol ameliorates ulcerative colitis by inhibiting ferroptosis based on the integrative analysis of plasma metabolomics and network pharmacology. Food Funct 2024; 15:6054-6067. [PMID: 38753306 DOI: 10.1039/d4fo00952e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
6-Gingerol (6-G), an active ingredient of ginger with anti-inflammation and anti-oxidation properties, can treat ulcerative colitis (UC). However, its underlying mechanism is still unclear. In this study, the pharmacodynamic evaluation of 6-G for treating UC was performed, and the mechanism of 6-G in ameliorating UC was excavated by plasma metabolomics and network pharmacology analysis, which was further validated by experimental and molecular docking. The results showed that 6-G could notably reduce diarrhea, weight loss, colonic pathological damage, and inflammation in UC mice. Plasma metabolomic results indicated that 6-G could regulate 19 differential metabolites, and its metabolic pathways mainly involved linoleic acid metabolism and arachidonic acid metabolism, which were closely associated with ferroptosis. Moreover, 60 potential targets for 6-G intervention on ferroptosis in UC were identified by network pharmacology, and enrichment analysis revealed that 6-G suppressed ferroptosis by modulating lipid peroxidation. Besides, the integration of metabolomics and network pharmacology showed that the regulation of 6-G on ferroptosis focused on 3 key targets, including ALOX5, ALOX15, and PTGS2. Further investigation indicated that 6-G significantly inhibited ferroptosis by decreasing iron load and malondialdehyde (MDA), and enhanced antioxidant capacity by reducing the content of glutathione disulfide (GSSG) and increasing the levels of superoxide dismutase (SOD) and glutathione (GSH) in UC mice and RSL3-induced Caco-2 cells. Furthermore, molecular docking showed the high affinity of 6-G with the identified 3 key targets. Collectively, this study elucidated the potential of 6-G in ameliorating UC by inhibiting ferroptosis. The integrated strategy also provided a theoretical basis for 6-G in treating UC.
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Affiliation(s)
- Wenwen Li
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing, 210023, PR China.
| | - Yun Zhang
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing, 210023, PR China.
| | - Quyi Wang
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing, 210023, PR China.
| | - Yu Wang
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing, 210023, PR China.
| | - Yuwen Fan
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing, 210023, PR China.
| | - Erxin Shang
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing, 210023, PR China.
| | - Shu Jiang
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing, 210023, PR China.
| | - Jinao Duan
- Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, 138 Xianlin Road, Nanjing, 210023, PR China.
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Yapici FI, Bebber CM, von Karstedt S. A guide to ferroptosis in cancer. Mol Oncol 2024; 18:1378-1396. [PMID: 38590214 PMCID: PMC11161738 DOI: 10.1002/1878-0261.13649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 02/20/2024] [Accepted: 03/26/2024] [Indexed: 04/10/2024] Open
Abstract
Ferroptosis is a newly identified iron-dependent type of regulated cell death that can also be regarded as death caused by the specific collapse of the lipid antioxidant defence machinery. Ferroptosis has gained increasing attention as a potential therapeutic strategy for therapy-resistant cancer types. However, many ferroptosis-inducing small molecules do not reach the pharmacokinetic requirements for their effective clinical use yet. Nevertheless, their clinical optimization is under development. In this review, we summarize the current understanding of molecular pathways regulating ferroptosis, how cells protect themselves from the induction of ferroptotic cell death, and how a better understanding of cancer cell metabolism can represent vulnerabilities for ferroptosis-based therapies. Lastly, we discuss the context-dependent effect of ferroptosis on various cell types within the tumor microenvironment and address controversies on how tissue ferroptosis might impact systemic cancer immunity in a paracrine manner.
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Affiliation(s)
- Fatma Isil Yapici
- Department of Translational Genomics, Faculty of Medicine and University Hospital CologneUniversity of CologneGermany
- CECAD Cluster of ExcellenceUniversity of CologneGermany
| | - Christina M. Bebber
- Department of Translational Genomics, Faculty of Medicine and University Hospital CologneUniversity of CologneGermany
- CECAD Cluster of ExcellenceUniversity of CologneGermany
| | - Silvia von Karstedt
- Department of Translational Genomics, Faculty of Medicine and University Hospital CologneUniversity of CologneGermany
- CECAD Cluster of ExcellenceUniversity of CologneGermany
- Center for Molecular Medicine Cologne, Faculty of Medicine and University Hospital CologneUniversity of CologneGermany
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Liu Z, Niu X, Wang J. Naringenin as a natural immunomodulator against T cell-mediated autoimmune diseases: literature review and network-based pharmacology study. Crit Rev Food Sci Nutr 2022; 63:11026-11043. [PMID: 35776085 DOI: 10.1080/10408398.2022.2092054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
T cells, especially CD4+ T helper (Th) cells, play a vital role in the pathogenesis of specific autoimmune diseases. Naringenin, a citrus flavonoid, exhibits anti-inflammatory, anti-oxidant, and antitumor properties, which have been verified in animal autoimmune disease models. However, naringenin's possible effects and molecular mechanisms in T cell-mediated autoimmune diseases are unclear. This review summarizes the findings of previous studies and predicts the target of naringenin in T cell-mediated autoimmune disorders such as multiple sclerosis, inflammatory bowel disease, and rheumatoid arthritis through network pharmacology analysis. We performed DAVID enrichment analysis, protein-protein interaction analysis, and molecular docking to predict the positive effect of naringenin on T cell-mediated autoimmune disorders. Sixteen common genes were screened, among which the core genes were PTGS2, ESR1, CAT, CASP3, MAPK1, and AKT1. The possible molecular mechanism relates to HIF-1, estrogen, TNF, and NF-κB signaling pathways. Our findings have significance for future naringenin treatment of T cell-mediated autoimmune diseases.
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Affiliation(s)
- Zejin Liu
- Infection and Immunity Institute and Translational Medical Center of Huaihe Hospital, Henan University, Kaifeng, China
| | - Xinli Niu
- School of Life Sciences, Henan University, Kaifeng, China
| | - Junpeng Wang
- Infection and Immunity Institute and Translational Medical Center of Huaihe Hospital, Henan University, Kaifeng, China
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Kohansal F, Mobed A, Ansari R, Hasanzadeh M, Ahmadalipour A, Shadjou N. An innovative electrochemical immuno-platform towards ultra-sensitive monitoring of 2-arachidonoyl glycerol in samples from rats with sleep deprivation: bioanalysis of endogenous cannabinoids using biosensor technology. RSC Adv 2022; 12:14154-14166. [PMID: 35558840 PMCID: PMC9092357 DOI: 10.1039/d2ra00380e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 05/03/2022] [Indexed: 11/21/2022] Open
Abstract
The endocannabinoid system (ECS) is a complex of neurotransmitters in the central nervous system and plays a key role in regulating cognitive and physiological processes. 2-Arachidonoylglycerol (2-AG) is one of the imperative endocannabinoids that play key roles in the central nervous system. It acts as a signaling lipid and activates the cannabinoid CB1 receptor. In addition, 2-AG is involved in a variety of physiological functions such as energy balance, emotion, pain sensation, cognition, and neuroinflammation. So, rapid and specific diagnosis of 2-AG is of great importance in medical neuroscience. The development of new methods in this area has been one of the most important research areas in recent years. Herein, an innovative immunosensor is developed for quantification of 2-AG. For this means, gold nanostars (GNS) were synthesized and conjugated with a specific biotinylated antibody against 2-AG. The resultant bioconjugate, a bioreceptor with GNS, was immobilized on the surface of a gold electrode and used for the detection of the antigen based on the immunocomplex formation followed by analysis using different electrochemical techniques. For the first time, 2-AG protein was measured with an excellent linear range of 0.48–1 ng mL−1 and lower limit of quantification of 0.48 ng L−1 by the electroanalysis method. The engineered immunosensor showed high sensitivity and specificity in the presence of interfering antigens, proving its utility in neurological disorder detection. This immunosensor is the first sandwich type immunoassay for the detection of 2-AG in real samples and the first innovation of designing a novel sandwich type immunosensor for this analyte. Also, excellent analytical results are other advantages of this biosensor for the detection of 2-AG in human plasma samples and serum samples of rats under sleep deprivation. So, this is the first report of an immunosensor of 2-AG using a sandwich type immunosensor. A novel electrochemical immunosensor based gold nanoparticles for the sensitive recognition of 2-AG was introduced.![]()
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Affiliation(s)
- Fereshteh Kohansal
- Pharmaceutical Analysis Research Center, Tabriz University of Medical Sciences Tabriz 51664 Iran
| | - Ahmad Mobed
- Aging Research Institute, Faculty of Medicine, Tabriz University of Medical Sciences Iran.,Physical Medicine and Rehabilitation Research Center, Tabriz University of Medical Sciences Tabriz Iran
| | - Rana Ansari
- Drug Applied Research Center, Tabriz University of Medical Sciences Iran
| | - Mohammad Hasanzadeh
- Pharmaceutical Analysis Research Center, Tabriz University of Medical Sciences Tabriz 51664 Iran .,Nutrition Research Center, Tabriz University of Medical Sciences Tabriz Iran
| | - Ali Ahmadalipour
- Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences Iran
| | - Nasrin Shadjou
- Department of Nanochemistry, Nanotechnology Research Center, Faculty of Science and Chemistry, Urmia University Urmia Iran
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Chasovskikh NY, Chizhik EE, Bobrysheva AA. Bioinformatic Annotation of Genes for Alzheimer’s Disease and Coronary Heart Disease. RUSS J GENET+ 2021. [DOI: 10.1134/s102279542111003x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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6
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Shi L, Liu Y, Li M, Luo Z. Emerging roles of ferroptosis in the tumor immune landscape: from danger signals to anti-tumor immunity. FEBS J 2021; 289:3655-3665. [PMID: 34042258 DOI: 10.1111/febs.16034] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/11/2021] [Accepted: 05/24/2021] [Indexed: 12/13/2022]
Abstract
Regulated cell death (RCD) is a vital event in various physiological and pathological processes. Ferroptosis is a newly described RCD, which is driven by iron accumulation and unrestricted lipid peroxidation. The interaction between ferroptosis and immunity has been a topic of substantial interest since its discovery in 2012. It has become increasingly evident that ferroptosis is critically involved in the regulation of antitumor immunity and may provide potential strategies in immunotherapy. Ferroptosis could release various damage-associated molecular patterns (DAMPs) or lipid metabolites to regulate the cellular immune response, validating its role as a form of immunogenic cell death (ICD). Specifically, the oxygenated membrane lipids on ferroptotic cells could mediate the phagocytosis by macrophages to maintain the immune responses. Additionally, immune checkpoint inhibitor therapy may sensitize cancer cells to ferroptosis, while ferroptosis might contribute to tumor immune evasion by directly interfering with the function of various immune cells. Based on these insights, we provided a comprehensive review on the interaction patterns between ferroptosis and immunity, which may not only offer insight into the underlying regulatory mechanisms but also facilitating the development of ferroptosis-based antitumor therapeutics.
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Affiliation(s)
- Lei Shi
- School of Life Science, Chongqing University, China
| | - Yingqi Liu
- School of Life Science, Chongqing University, China
| | - Menghuan Li
- School of Life Science, Chongqing University, China
| | - Zhong Luo
- School of Life Science, Chongqing University, China
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7
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Uddin MJ, Xu S, Crews BC, Aleem AM, Ghebreselasie K, Banerjee S, Marnett LJ. Harmaline Analogs as Substrate-Selective Cyclooxygenase-2 Inhibitors. ACS Med Chem Lett 2020; 11:1881-1885. [PMID: 33062168 DOI: 10.1021/acsmedchemlett.9b00555] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 02/14/2020] [Indexed: 11/28/2022] Open
Abstract
We report the design, synthesis, and evaluation of a series of harmaline analogs as selective inhibitors of 2-arachidonylglycerol (2-AG) oxygenation over arachidonic acid (AA) oxygenation by purified cyclooxygenase-2 (COX-2). A fused tricyclic harmaline analog containing a CH3O substituent at C-6 and a CH3 group at the C-1 position of 4,9-dihydro-3H-pyrido[3,4-b]indole (compound 3) was the best substrate-selective COX-2 inhibitor of those evaluated, exhibiting a 2AG-selective COX-2 inhibitory IC50 of 0.022 μM as compared to >1 μM for AA. The 2.66 Å resolution crystal complex of COX-2 with compound 3 revealed that this series of tricyclic indoles binds in the cyclooxygenase channel by flipping the side chain of L531 toward the dimer interface. This novel tricyclic indole series provides the foundation for the development of promising substrate-selective molecules capable of increasing endocannabinoid (EC) levels in the brain to offer new treatments for a variety of diseases, from pain and inflammation to stress and anxiety disorders.
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Affiliation(s)
- Md. Jashim Uddin
- A. B. Hancock, Jr., Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Shu Xu
- A. B. Hancock, Jr., Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Brenda C. Crews
- A. B. Hancock, Jr., Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Ansari M. Aleem
- A. B. Hancock, Jr., Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Kebreab Ghebreselasie
- A. B. Hancock, Jr., Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Surajit Banerjee
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
- Northeastern Collaborative Access Team, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Lawrence J. Marnett
- A. B. Hancock, Jr., Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, and Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
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Kingsley PJ, Rouzer CA, Morgan AJ, Patel S, Marnett LJ. Aspects of Prostaglandin Glycerol Ester Biology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1161:77-88. [PMID: 31562623 DOI: 10.1007/978-3-030-21735-8_8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The Cyclooxygenase enzymes (COX-1 and COX-2) incorporate 2 molecules of O2 into arachidonic acid (AA), resulting in an array of bioactive prostaglandins. However, much work has been done showing that COX-2 will perform this reaction on several different AA-containing molecules, most importantly, the endocannabinoid 2-arachidonoylglycerol (2-AG). The products of 2-AG oxygenation, prostaglandin glycerol esters (PG-Gs), are analogous to canonical prostaglandins. This chapter reviews the literature detailing the production, metabolism, and bioactivity of these compounds, as well as their detection in intact animals.
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Affiliation(s)
- Philip J Kingsley
- A. B. Hancock Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, USA
| | - Carol A Rouzer
- A. B. Hancock Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Amanda J Morgan
- A. B. Hancock Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Sachin Patel
- Department of Psychiatry and Behavioral Sciences, Department of Molecular Physiology & Biophysics, and the Vanderbilt Brain Institute, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lawrence J Marnett
- A. B. Hancock Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry, and Pharmacology, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, USA.
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Proneth B, Conrad M. Ferroptosis and necroinflammation, a yet poorly explored link. Cell Death Differ 2019; 26:14-24. [PMID: 30082768 PMCID: PMC6294786 DOI: 10.1038/s41418-018-0173-9] [Citation(s) in RCA: 214] [Impact Index Per Article: 42.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 06/14/2018] [Accepted: 07/10/2018] [Indexed: 12/20/2022] Open
Abstract
Ferroptosis is a non-apoptotic form of cell death characterized by overwhelming iron-dependent lipid peroxidation, which contributes to a number of pathologies, most notably tissue ischemia/reperfusion injury, neurodegeneration and cancer. Cysteine availability, glutathione biosynthesis, polyunsaturated fatty acid metabolism and modulation of the phospholipidome are the key events of this necrotic cell death pathway. Non-enzymatic and enzymatic lipoxygenase (LOX)-mediated lipid peroxidation of lipid bilayers is efficiently counteracted by the glutathione (GSH)/glutathione peroxidase 4 (GPX4) axis. Preliminary studies suggest that bursting ferroptotic cells release pro-inflammatory damage-associated molecular patterns (DAMPs) that trigger the innate immune system as exemplified by diseased kidney and brain tissues where ferroptosis contributes to organ demise in a predominant manner. The GSH/GPX4 node is known to control the activities of LOX and prostaglandin-endoperoxide synthase (PTGS) via the so-called peroxide tone. Since LOX and PTGS products do have pro- and anti-inflammatory effects, one may speculate that these enzymes contribute to the ferroptotic process on several levels in cell-autonomous and non-autonomous ways. Hence, this review provides the reader with an outline on what is currently known about the link between ferroptosis and necroinflammation and discusses critical events that may alert the innate immune system in early phases when cells become sensitized towards ferroptosis.
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Affiliation(s)
- Bettina Proneth
- Institute of Developmental Genetics, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Marcus Conrad
- Institute of Developmental Genetics, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.
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10
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Orlando BJ, Malkowski MG. Substrate-selective Inhibition of Cyclooxygeanse-2 by Fenamic Acid Derivatives Is Dependent on Peroxide Tone. J Biol Chem 2016; 291:15069-81. [PMID: 27226593 DOI: 10.1074/jbc.m116.725713] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Indexed: 12/13/2022] Open
Abstract
Cyclooxygenase-2 (COX-2) catalyzes the oxygenation of arachidonic acid (AA) and endocannabinoid substrates, placing the enzyme at a unique junction between the eicosanoid and endocannabinoid signaling pathways. COX-2 is a sequence homodimer, but the enzyme displays half-of-site reactivity, such that only one monomer of the dimer is active at a given time. Certain rapid reversible, competitive nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to inhibit COX-2 in a substrate-selective manner, with the binding of inhibitor to a single monomer sufficient to inhibit the oxygenation of endocannabinoids but not arachidonic acid. The underlying mechanism responsible for substrate-selective inhibition has remained elusive. We utilized structural and biophysical methods to evaluate flufenamic acid, meclofenamic acid, mefenamic acid, and tolfenamic acid for their ability to act as substrate-selective inhibitors. Crystal structures of each drug in complex with human COX-2 revealed that the inhibitor binds within the cyclooxygenase channel in an inverted orientation, with the carboxylate group interacting with Tyr-385 and Ser-530 at the top of the channel. Tryptophan fluorescence quenching, continuous-wave electron spin resonance, and UV-visible spectroscopy demonstrate that flufenamic acid, mefenamic acid, and tolfenamic acid are substrate-selective inhibitors that bind rapidly to COX-2, quench tyrosyl radicals, and reduce higher oxidation states of the heme moiety. Substrate-selective inhibition was attenuated by the addition of the lipid peroxide 15-hydroperoxyeicosatertaenoic acid. Collectively, these studies implicate peroxide tone as an important mechanistic component of substrate-selective inhibition by flufenamic acid, mefenamic acid, and tolfenamic acid.
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Affiliation(s)
- Benjamin J Orlando
- From the Department of Structural Biology, The State University of New York at Buffalo and
| | - Michael G Malkowski
- From the Department of Structural Biology, The State University of New York at Buffalo and the Hauptman-Woodward Medical Research Institute, Buffalo, New York 14203
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11
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Competition and allostery govern substrate selectivity of cyclooxygenase-2. Proc Natl Acad Sci U S A 2015; 112:12366-71. [PMID: 26392530 DOI: 10.1073/pnas.1507307112] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cyclooxygenase-2 (COX-2) oxygenates arachidonic acid (AA) and its ester analog, 2-arachidonoylglycerol (2-AG), to prostaglandins (PGs) and prostaglandin glyceryl esters (PG-Gs), respectively. Although the efficiency of oxygenation of these substrates by COX-2 in vitro is similar, cellular biosynthesis of PGs far exceeds that of PG-Gs. Evidence that the COX enzymes are functional heterodimers suggests that competitive interaction of AA and 2-AG at the allosteric site of COX-2 might result in differential regulation of the oxygenation of the two substrates when both are present. Modulation of AA levels in RAW264.7 macrophages uncovered an inverse correlation between cellular AA levels and PG-G biosynthesis. In vitro kinetic analysis using purified protein demonstrated that the inhibition of 2-AG oxygenation by high concentrations of AA far exceeded the inhibition of AA oxygenation by high concentrations of 2-AG. An unbiased systems-based mechanistic model of the kinetic data revealed that binding of AA or 2-AG at the allosteric site of COX-2 results in a decreased catalytic efficiency of the enzyme toward 2-AG, whereas 2-AG binding at the allosteric site increases COX-2's efficiency toward AA. The results suggest that substrates interact with COX-2 via multiple potential complexes involving binding to both the catalytic and allosteric sites. Competition between AA and 2-AG for these sites, combined with differential allosteric modulation, gives rise to a complex interplay between the substrates, leading to preferential oxygenation of AA.
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12
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Kukk K, Kasvandik S, Samel N. N-glycosylation site occupancy in human prostaglandin H synthases expressed in Pichia pastoris. SPRINGERPLUS 2014; 3:436. [PMID: 25170432 PMCID: PMC4147080 DOI: 10.1186/2193-1801-3-436] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 08/12/2014] [Indexed: 11/10/2022]
Abstract
Prostaglandin H synthases (PGHSs) are N-glycosylated membrane proteins that catalyse the committed step in prostaglandin synthesis. Unlike PGHS-2, the production of recombinant PGHS-1 in non-mammalian expression systems is complicated. The majority of the heterologous enzyme is inactive due to misfolding. Correct N-glycosylation is proposed to be obligatory for proper folding of mammalian PGHSs. In this study, human PGHS-1 and -2 (hPGHS-1 and -2) were expressed in the yeast Pichia pastoris. Recombinant hPGHS-2 was catalytically active, whereas hPGHS-1 was inactive. Accumulation of non-glycosylated hPGHSs was not observed in the crude lysate of the yeast cells. The N-glycosylation patterns of the purified recombinant proteins were characterised using nano-LC/MS/MS. The isoforms exhibited similar N-glycosylation site occupancy. The results indicate that there are more complex grounds for the inactivity of the recombinant hPGHS-1 produced in yeast.
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Affiliation(s)
- Kaia Kukk
- Department of Chemistry, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia
| | - Sergo Kasvandik
- Proteomics Core Facility, Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Nigulas Samel
- Department of Chemistry, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia
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13
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Giordano E, Visioli F. Long-chain omega 3 fatty acids: molecular bases of potential antioxidant actions. Prostaglandins Leukot Essent Fatty Acids 2014; 90:1-4. [PMID: 24345866 DOI: 10.1016/j.plefa.2013.11.002] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 11/15/2013] [Accepted: 11/18/2013] [Indexed: 12/20/2022]
Abstract
Several lines of investigation are being developed to assess the impact of polyunsaturated fatty acids, namely those of the omega 3 series, intake on oxidative stress. Keeping in mind that there might be a dose-response relation, in vivo and in vitro data strongly suggest that omega 3 fatty acids might act as anti- rather than pro-oxidant in several cells such as vascular cells, hence diminishing inflammation, oxidative stress, and, in turn, the risk of atherosclerosis and degenerative disorders such as cardiovascular disease.
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Affiliation(s)
- Elena Giordano
- Laboratory of Functional Foods, Madrid Institute for Advanced Studies (IMDEA)-Food, CEI UAM+CSIC, Madrid, Spain
| | - Francesco Visioli
- Laboratory of Functional Foods, Madrid Institute for Advanced Studies (IMDEA)-Food, CEI UAM+CSIC, Madrid, Spain.
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