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Measurement of Reactive Oxygen Species (ROS) and Mitochondrial ROS in AMPK Knockout Mice Blood Vessels. Methods Mol Biol 2018; 1732:507-517. [PMID: 29480496 DOI: 10.1007/978-1-4939-7598-3_32] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Reactive oxygen species (ROS) are a group of unstable and highly reactive molecules or free radicals typically generated as by-products of cellular processes involving molecular oxygen. In vascular cells, the excessive ROS generation results in the initiation and progression of cardiovascular diseases (CVD). Therefore, a dynamic, robust, and accurate ROS detection method in the blood vessels is essential for pathophysiological research studies of the cardiovascular system.In this chapter, we describe a fluorescence dye-based detection method for assaying superoxide and mitochondrial superoxide in mouse aorta using dihydroethidium (DHE) and MitoSOX. The protocol includes preparation of frozen aortic tissue sections, monitoring DHE oxidation-derived fluorescence by fluorescence microscopy, and high-performance liquid chromatograph-based analysis of MitoSOX and its oxidation products. For studying the role of AMP-activated protein kinase (AMPK) in the redox regulation, we employed AMPKα2 knockout mice and observed increased superoxide and mitochondrial superoxide levels in the aorta of AMPK knockout mice relative to the wild-type group. This novel ROS detection method will be valuable for investigating the roles of cellular and/or mitochondrial ROS in the pathogenesis of CVDs.
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Trans-Plasma Membrane Electron Transport and Ascorbate Efflux by Skeletal Muscle. Antioxidants (Basel) 2017; 6:antiox6040089. [PMID: 29120354 PMCID: PMC5745499 DOI: 10.3390/antiox6040089] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 11/07/2017] [Accepted: 11/07/2017] [Indexed: 12/17/2022] Open
Abstract
Trans-plasma membrane electron transport (tPMET) and the antioxidant roles of ascorbate reportedly play a role in protection of cells from damage by reactive oxygen species, which have been implicated in causing metabolic dysfunction such as insulin resistance. Skeletal muscle comprises the largest whole-body organ fraction suggesting a potential role of tPMET and ascorbate export as a major source of extracellular antioxidant. We hypothesized that skeletal muscle is capable of tPMET and ascorbate efflux. To measure these processes, we assayed the ability of cultured muscle cells, satellite cells, and isolated extensor digitorum longus (EDL) and soleus (SOL) to reduce two extracellular electron acceptors, water soluble tetrazolium salt 1 (WST-1), and dichlorophenolindophenol (DPIP). Ascorbate oxidase (AO) was utilized to determine which portion of WST-1 reduction was dependent on ascorbate efflux. We found that muscle cells can reduce extracellular electron acceptors. In C2C12 myotubes and satellite cells, a substantial portion of this reduction was dependent on ascorbate. In myotubes, glucose transporter 1 (GLUT1) inhibitors along with a pan-GLUT inhibitor suppressed tPMET and ascorbate efflux, while a GLUT4 inhibitor had no effect. The adenosine 5′-monophosphate (AMP)-activated protein kinase activator 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR) suppressed both tPMET and ascorbate efflux by myotubes, while insulin had no effect. Taken together, our data suggest that muscle cells are capable of tPMET and ascorbate efflux supported by GLUT1, thus illustrating a model in which resting muscle exports electrons and antioxidant to the extracellular environment.
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Duan Q, Song P, Ding Y, Zou MH. Activation of AMP-activated protein kinase by metformin ablates angiotensin II-induced endoplasmic reticulum stress and hypertension in mice in vivo. Br J Pharmacol 2017; 174:2140-2151. [PMID: 28436023 DOI: 10.1111/bph.13833] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 03/29/2017] [Accepted: 04/16/2017] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Metformin, one of the most frequently prescribed medications for type 2 diabetes, reportedly exerts BP-lowering effects in patients with diabetes. However, the effects and underlying mechanisms of metformin on BP in non-diabetic conditions remain to be determined. The aim of the present study was to determine the effects of metformin on angiotensin II (Ang II) infusion-induced hypertension in vivo. EXPERIMENTAL APPROACH The effects of metformin on BP were investigated in wild-type (WT) C57BL/6J mice and in mice lacking AMP-activated protein kinase α2 (AMPKα2) mice with or without Ang II infusion. Also, the effect of metformin on Ang II-induced endoplasmic reticulum (ER) stress was explored in cultured human vascular smooth muscle cells (hVSMCs). KEY RESULTS Metformin markedly reduced BP in Ang II-infused WT mice but not in AMPKα2-deficient mice. In cultured hVSMCs, Ang II treatment resulted in inactivation of AMPK, as well as the subsequent induction of spliced X-box binding protein-1, phosphorylation of eukaryotic translation initiation factor 2α and expression of glucose-regulated protein 78 kDa, representing three well-characterized ER stress biomarkers. Moreover, AMPK activation by metformin ablated Ang II-induced ER stress in hVSMCs. Mechanistically, metformin-activated AMPKα2 suppressed ER stress by increasing phospholamban phosphorylation. CONCLUSION AND IMPLICATIONS Metformin alleviates Ang II-triggered hypertension in mice by activating AMPKα2, which mediates phospholamban phosphorylation and inhibits Ang II-induced ER stress in vascular smooth muscle cells.
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Affiliation(s)
- Quanlu Duan
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, USA.,Division of Cardiology, Department Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ping Song
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, USA
| | - Ye Ding
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, USA
| | - Ming-Hui Zou
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, USA
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Wang X, Xue GX, Liu WC, Shu H, Wang M, Sun Y, Liu X, Sun YE, Liu CF, Liu J, Liu W, Jin X. Melatonin alleviates lipopolysaccharide-compromised integrity of blood-brain barrier through activating AMP-activated protein kinase in old mice. Aging Cell 2017; 16:414-421. [PMID: 28156052 PMCID: PMC5334533 DOI: 10.1111/acel.12572] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2016] [Indexed: 11/26/2022] Open
Abstract
Blood–brain barrier (BBB) dysfunction is considered to be an early event in the pathogenesis of a variety of neurological diseases in old patients, and this could occur in old people even when facing common stress. However, the mechanism remains to be defined. In this study, we tested the hypothesis that decreased melatonin levels may account for the BBB disruption in old mice challenged with lipopolysaccharide (LPS), which mimicked the common stress of sepsis. Mice (24–28 months of age) received melatonin (10 mg kg−1 day−1, intraperitoneally, i.p.) or saline for one week before exposing to LPS (1 mg kg−1, i.p.). Evan's blue dye (EB) and immunoglobulin G (IgG) leakage were used to assess BBB permeability. Immunostaining and Western blot were used to detect protein expression and distribution. Our results showed that LPS significantly increased BBB permeability in old mice accompanied by the degradation of tight junction proteins occludin and claudin‐5, suppressed AMP‐activated protein kinase (AMPK) activation, and elevated gp91phox protein expression. Interestingly, administration of melatonin for one week significantly decreased LPS‐induced BBB disruption, AMPK suppression, and gp91phox upregualtion. Moreover, activation of AMPK with metformin significantly inhibited LPS‐induced gp91phox upregualtion in endothelial cells. Taken together, our findings demonstrate that melatonin alleviates LPS‐induced BBB disruption through activating AMPK and inhibiting gp91phox upregulation in old mice.
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Affiliation(s)
- Xiaona Wang
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and Institute of Neuroscience; The Second Affiliated Hospital of Soochow University; Suzhou 215004 China
| | - Gai-Xiu Xue
- Suzhou Municipal Hospital; Suzhou 215002 China
| | - Wen-Cao Liu
- Department of Emergency; Shanxi Provincial People's Hospital; Taiyuan 030001 China
| | - Hui Shu
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and Institute of Neuroscience; The Second Affiliated Hospital of Soochow University; Suzhou 215004 China
| | - Mengwei Wang
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and Institute of Neuroscience; The Second Affiliated Hospital of Soochow University; Suzhou 215004 China
| | - Yanyun Sun
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and Institute of Neuroscience; The Second Affiliated Hospital of Soochow University; Suzhou 215004 China
| | - Xiaojing Liu
- Translational Center for Stem Cell Research; Tongji Hospital; Stem Cell Research Center; Tongji University School of Medicine; Shanghai 200065 China
| | - Yi Eve Sun
- Translational Center for Stem Cell Research; Tongji Hospital; Stem Cell Research Center; Tongji University School of Medicine; Shanghai 200065 China
- Department of Psychiatry and Biobehavioral Sciences; David Geffen School of Medicine; University of California, Los Angeles; Los Angeles CA 90095 USA
| | - Chun-Feng Liu
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and Institute of Neuroscience; The Second Affiliated Hospital of Soochow University; Suzhou 215004 China
- Department of Neurology; Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases; The Second Affiliated Hospital of Soochow University; Soochow University; Suzhou 215004 China
| | - Jie Liu
- Translational Center for Stem Cell Research; Tongji Hospital; Stem Cell Research Center; Tongji University School of Medicine; Shanghai 200065 China
| | - Wenlan Liu
- The Central Laboratory; Shenzhen Second People's Hospital; the First Affiliated Hospital of Shenzhen University; Shenzhen 518035 China
| | - Xinchun Jin
- Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and Institute of Neuroscience; The Second Affiliated Hospital of Soochow University; Suzhou 215004 China
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55
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Zhang M, Yang D, Gong X, Ge P, Dai J, Lin L, Zhang L. Protective benefits of AMP-activated protein kinase in hepatic ischemia-reperfusion injury. Am J Transl Res 2017; 9:823-829. [PMID: 28386315 PMCID: PMC5375980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 02/12/2017] [Indexed: 06/07/2023]
Abstract
Hepatic ischemia-reperfusion injury (HIRI) is a major cause of hepatic failure and death after liver trauma, haemorrhagic shock, resection surgery and liver transplantation. AMP-activated protein kinase (AMPK) is an energy sensitive kinase that plays crucial roles in the regulation of metabolic homeostasis. In HIRI, ischemia induces the decline of ATP and the increased ratio of AMP/ATP, which promotes the phosphorylation and activation of AMPK. Three AMPK kinases, liver kinase B1 (LKB1), Ca2+/calmodulin-depedent protein kinase kinase β (CaMKKβ) and TGF-β-activated kinase-1 (TAK1), are main upstream kinases for the phosphorylation of AMPK. In addition to the changed AMP/ATP ratio, the activated CaMKKβ by increased intracelluar Ca2+ and the overproduction of reactive oxygen species (ROS) are also involved in the activation of AMPK during HIRI. The activated AMPK might provide protective benefits in HIRI via prevention of energy decline, inhibition of inflammatory response, suppression of hepatocyte apoptosis and attenuation of oxidative stress. Thus, AMPK might become a novel target for the pharmacological intervention of HIRI.
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Affiliation(s)
- Min Zhang
- Department of Pathophysiology, Chongqing Medical UniversityChongqing, China
| | - Dan Yang
- Department of Pathophysiology, Chongqing Medical UniversityChongqing, China
| | - Xianqiong Gong
- Hepatology Center, Xiamen Hospital of Traditional Chinese MedicineXiamen, Fujian Province, China
| | - Pu Ge
- Department of Pathophysiology, Chongqing Medical UniversityChongqing, China
| | - Jie Dai
- Hospital of Chongqing University of Arts and SciencesChongqing, China
| | - Ling Lin
- Department of Pathophysiology, Chongqing Medical UniversityChongqing, China
| | - Li Zhang
- Department of Pathophysiology, Chongqing Medical UniversityChongqing, China
- Laboratory of Stem Cell and Tissue Engineering, Chongqing Medical UniversityChongqing, China
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56
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Liu D, Ding Z, Wu M, Xu W, Qian M, Du Q, Zhang L, Cui Y, Zheng J, Chang H, Huang C, Lin D, Wang Y. The apolipoprotein A-I mimetic peptide, D-4F, alleviates ox-LDL-induced oxidative stress and promotes endothelial repair through the eNOS/HO-1 pathway. J Mol Cell Cardiol 2017; 105:77-88. [PMID: 28274624 DOI: 10.1016/j.yjmcc.2017.01.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Revised: 12/30/2016] [Accepted: 01/27/2017] [Indexed: 02/08/2023]
Abstract
Apolipoprotein A-I (apoA-I) mimetic peptide exerts many anti-atherogenic properties. However, the underlying mechanisms related to the endothelial protective effects remain elusive. In this study, the apoA-I mimetic peptide, D-4F, was used. Proliferation assay, wound healing, and transwell migration experiments showed that D-4F improved the impaired endothelial proliferation and migration resulting from ox-LDL. Endothelial adhesion molecules expression and monocyte adhesion assay demonstrated that D-4F inhibited endothelial inflammation. Caspase-3 activation and TUNEL stain indicated that D-4F reduced endothelial cell apoptosis. A pivotal anti-oxidant enzyme, heme oxygenase-1 (HO-1) was upregulated by D-4F. The Akt/AMPK/eNOS pathways were involved in the expression of HO-1 induced by D-4F. Moreover, the anti-oxidation, pro-proliferation, and pro-migration capacities of D-4F were diminished by the inhibitors of both eNOS (L-NAME) and HO-1 (Znpp). Additionally, downregulation of ATP-binding cassette transporter A1 (ABCA1) by siRNA abolished the activation of Akt, AMPK and eNOS, and reduced the upregulation of HO-1 triggered by D-4F. Furthermore, D-4F promoted the reendothelialization of injured intima in carotid artery injury model of C57BL/6J mice in vivo. In summary, these findings suggested that D-4F might be a powerful candidate in the protection of endothelial cells and the prevention of cardiovascular disease (CVD).
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Affiliation(s)
- Donghui Liu
- Department of Cardiology, the Affiliated Xiamen Cardiovascular Hospital of Xiamen University, Medical College of Xiamen University, Xiamen 361004, China.
| | - Zhenzhen Ding
- Department of Cardiology, the Affiliated Xiamen Cardiovascular Hospital of Xiamen University, Medical College of Xiamen University, Xiamen 361004, China; Union Clinical Medical College of Fujian Medical University, Fuzhou 350001, China
| | - Mengzhang Wu
- Department of Cardiology, the Affiliated Xiamen Cardiovascular Hospital of Xiamen University, Medical College of Xiamen University, Xiamen 361004, China; Union Clinical Medical College of Fujian Medical University, Fuzhou 350001, China
| | - Wenqi Xu
- High-field NMR Research Center, MOE Key Laboratory of Spectrochemical Analysis& Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Mingming Qian
- Department of Cardiology, the Affiliated Xiamen Cardiovascular Hospital of Xiamen University, Medical College of Xiamen University, Xiamen 361004, China
| | - Qian Du
- Department of Cardiology, the Affiliated Xiamen Cardiovascular Hospital of Xiamen University, Medical College of Xiamen University, Xiamen 361004, China
| | - Le Zhang
- Department of Cardiology, the Affiliated Xiamen Cardiovascular Hospital of Xiamen University, Medical College of Xiamen University, Xiamen 361004, China
| | - Ye Cui
- Department of Ob/Gyn and Neonatal and Reproductive Medicine, the People's Liberation Army 174th Hospital and the Affiliated Hospital of Xiamen University, Xiamen 361003, China
| | - Jianlan Zheng
- Department of Ob/Gyn and Neonatal and Reproductive Medicine, the People's Liberation Army 174th Hospital and the Affiliated Hospital of Xiamen University, Xiamen 361003, China
| | - He Chang
- Department of Cardiology, the Affiliated Xiamen Cardiovascular Hospital of Xiamen University, Medical College of Xiamen University, Xiamen 361004, China
| | - Caihua Huang
- Department of Physical Education, Xiamen University of Technology, Xiamen 361021, China
| | - Donghai Lin
- High-field NMR Research Center, MOE Key Laboratory of Spectrochemical Analysis& Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Yan Wang
- Department of Cardiology, the Affiliated Xiamen Cardiovascular Hospital of Xiamen University, Medical College of Xiamen University, Xiamen 361004, China.
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Sylow L, Kleinert M, Richter EA, Jensen TE. Exercise-stimulated glucose uptake - regulation and implications for glycaemic control. Nat Rev Endocrinol 2017; 13:133-148. [PMID: 27739515 DOI: 10.1038/nrendo.2016.162] [Citation(s) in RCA: 265] [Impact Index Per Article: 37.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Skeletal muscle extracts glucose from the blood to maintain demand for carbohydrates as an energy source during exercise. Such uptake involves complex molecular signalling processes that are distinct from those activated by insulin. Exercise-stimulated glucose uptake is preserved in insulin-resistant muscle, emphasizing exercise as a therapeutic cornerstone among patients with metabolic diseases such as diabetes mellitus. Exercise increases uptake of glucose by up to 50-fold through the simultaneous stimulation of three key steps: delivery, transport across the muscle membrane and intracellular flux through metabolic processes (glycolysis and glucose oxidation). The available data suggest that no single signal transduction pathway can fully account for the regulation of any of these key steps, owing to redundancy in the signalling pathways that mediate glucose uptake to ensure maintenance of muscle energy supply during physical activity. Here, we review the molecular mechanisms that regulate the movement of glucose from the capillary bed into the muscle cell and discuss what is known about their integrated regulation during exercise. Novel developments within the field of mass spectrometry-based proteomics indicate that the known regulators of glucose uptake are only the tip of the iceberg. Consequently, many exciting discoveries clearly lie ahead.
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Affiliation(s)
- Lykke Sylow
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Maximilian Kleinert
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
- Institute for Diabetes and Obesity, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Erik A Richter
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Thomas E Jensen
- Molecular Physiology Group, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
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58
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Veeranki SP. Metformin use and asthma: Further investigations. Respirology 2016; 22:203. [PMID: 27782343 DOI: 10.1111/resp.12923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Accepted: 08/29/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Sreenivas P Veeranki
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, Texas, USA
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59
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Choi SM, Jang AH, Kim H, Lee KH, Kim YW. Metformin Reduces Bleomycin-induced Pulmonary Fibrosis in Mice. J Korean Med Sci 2016; 31:1419-25. [PMID: 27510385 PMCID: PMC4974183 DOI: 10.3346/jkms.2016.31.9.1419] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 05/19/2016] [Indexed: 12/31/2022] Open
Abstract
Metformin has anti-inflammatory and anti-fibrotic effects. We investigated whether metformin has an inhibitory effect on bleomycin (BLM)-induced pulmonary fibrosis in a murine model. A total of 62 mice were divided into 5 groups: control, metformin (100 mg/kg), BLM, and BLM with metformin (50 mg/kg or 100 mg/kg). Metformin was administered to the mice orally once a day from day 1. We sacrificed half of the mice on day 10 and collected the bronchoalveolar lavage fluid (BALF) from their left lungs. The remaining mice were sacrificed and analyzed on day 21. The right lungs were harvested for histological analyses. The messenger RNA (mRNA) levels of epithelial-mesenchymal transition markers were determined via analysis of the harvested lungs on day 21. The mice treated with BLM and metformin (50 mg/kg or 100 mg/kg) showed significantly lower levels of inflammatory cells in the BALF compared with the BLM-only mice on days 10 and 21. The histological examination revealed that the metformin treatment led to a greater reduction in inflammation than the treatment with BLM alone. The mRNA levels of collagen, collagen-1, procollagen, fibronectin, and transforming growth factor-β in the metformin-treated mice were lower than those in the BLM-only mice on day 21, although statistical significance was observed only in the case of procollagen due to the small number of live mice in the BLM-only group. Additionally, treatment with metformin reduced fibrosis to a greater extent than treatment with BLM alone. Metformin suppresses the inflammatory and fibrotic processes of BLM-induced pulmonary fibrosis in a murine model.
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Affiliation(s)
- Sun Mi Choi
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea
| | - An Hee Jang
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea
| | - Hyojin Kim
- Department of Pathology, Seoul National University Hospital, Seoul, Korea
| | - Kyu Hwa Lee
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea
| | - Young Whan Kim
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
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An H, Wei R, Ke J, Yang J, Liu Y, Wang X, Wang G, Hong T. Metformin attenuates fluctuating glucose-induced endothelial dysfunction through enhancing GTPCH1-mediated eNOS recoupling and inhibiting NADPH oxidase. J Diabetes Complications 2016; 30:1017-24. [PMID: 27217019 DOI: 10.1016/j.jdiacomp.2016.04.018] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/17/2016] [Accepted: 04/24/2016] [Indexed: 11/21/2022]
Abstract
AIMS The aim of this study was to investigate whether and how metformin ameliorated endothelial dysfunction induced by fluctuating glucose (FG) in human umbilical vein endothelial cells (HUVECs). METHODS HUVECs, which were exposed to FG to induce endothelial dysfunction, were incubated with nitric oxide synthase (NOS) inhibitor N-nitro-l-arginine-methyl ester (l-NAME), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor apocynin, metformin and/or adenosine monophosphate-activated protein kinase (AMPK) inhibitor compound C. The oxidative stress and endothelial NOS (eNOS) coupling were evaluated. RESULTS FG induced endothelial dysfunction as indicated by increased reactive oxygen species (ROS) generation and decreased nitric oxide (NO) production. Although FG increased eNOS phosphorylation, uncoupled eNOS was evidenced by downregulated guanosine 5'-triphosphate cyclohydrolase 1 (GTPCH1) and tetrahydrobiopterin (BH4) levels. FG also upregulated the level of p47-phox, a subunit of NADPH oxidase. Similar to l-NAME and apocynin, metformin ameliorated the FG-induced endothelial dysfunction by decreasing ROS generation. Furthermore, metformin recoupled eNOS through upregulating GTPCH1 and BH4 levels, and attenuated the upregulation of p47-phox in FG-treated HUVECs. Addition of compound C abolished the above effects of metformin. CONCLUSION Metformin improves the FG-induced endothelial dysfunction in HUVECs. The protective effect of metformin may be mediated through activation of GTPCH1-mediated eNOS recoupling and inhibition of NADPH oxidase via an AMPK-dependent pathway.
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Affiliation(s)
- Huijie An
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China; Department of Endocrinology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Rui Wei
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Jing Ke
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Jin Yang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Ye Liu
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China
| | - Xian Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Guang Wang
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China; Department of Endocrinology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
| | - Tianpei Hong
- Department of Endocrinology and Metabolism, Peking University Third Hospital, Beijing, China.
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Abstract
SIGNIFICANCE Reactive oxygen species (ROS) reactive nitrogen species (RNS) and redox processes are of key importance in obesity- and diabetes-related kidney disease; however, there remains significant controversy in the field. RECENT ADVANCES New data from imaging and in vivo models of obesity and diabetic kidney disease have shed new insights into this field. In the setting of obesity- and diabetes-related kidney injury, there is a growing recognition that the major moieties of ROS and RNS are hydrogen peroxide and peroxynitrite with the enzymatic sources being NADPH oxidases and nitric oxide synthase, respectively. However, the role of mitochondrial superoxide as a driver of renal complications remains unclear. CRITICAL ISSUES Several key issues that are often not discussed are the specific ROS and RNS molecules, the source of generation, the location of production, and downstream targets. FUTURE DIRECTIONS Further understanding of the role of ROS/RNS/redox and their relationship with key signaling and metabolic pathways such as AMP-activated protein kinase (AMPK) and hypoxia-inducible factor 1-α (HIF1α) will be critical to a new understanding of kidney complications of caloric challenges and new therapeutic approaches. Antioxid. Redox Signal. 25, 208-216.
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Affiliation(s)
- Kumar Sharma
- 1 Center for Renal Translational Medicine, Institute of Metabolomic Medicine, University of California San Diego , La Jolla, California.,2 Division of Nephrology-Hypertension, Veterans Affairs San Diego Healthcare System , La Jolla, California
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Choy KW, Mustafa MR, Lau YS, Liu J, Murugan D, Lau CW, Wang L, Zhao L, Huang Y. Paeonol protects against endoplasmic reticulum stress-induced endothelial dysfunction via AMPK/PPARδ signaling pathway. Biochem Pharmacol 2016; 116:51-62. [PMID: 27449753 DOI: 10.1016/j.bcp.2016.07.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 07/18/2016] [Indexed: 12/31/2022]
Abstract
Endoplasmic reticulum (ER) stress in endothelial cells often leads to endothelial dysfunction which underlies the pathogenesis of cardiovascular diseases. Paeonol, a major phenolic component extracted from Moutan Cortex, possesses various medicinal benefits which have been used extensively in traditional Chinese medicine. The present study investigated the protective mechanism of paeonol against tunicamycin-induced ER stress in isolated mouse aortas and human umbilical vein endothelial cells (HUVECs). Vascular reactivity in aorta was measured using a wire myograph. The effects of paeonol on protein expression of ER stress markers, reactive oxygen species (ROS) production, nitric oxide (NO) bioavailability and peroxisome proliferator-activated receptor δ (PPARδ) activity in the vascular wall were assessed by Western blot, dihydroethidium fluorescence (DHE) or lucigenin enhanced-chemiluminescence, 4-amino-5-methylamino-2',7'-difluorofluorescein (DAF-FM DA) and dual luciferase reporter assay, respectively. Ex vivo treatment with paeonol (0.1μM) for 16h reversed the impaired endothelium-dependent relaxations in C57BJ/6J and PPARδ wild type (WT) mouse aortas following incubation with tunicamycin (0.5μg/mL). Elevated ER stress markers, oxidative stress and reduction of NO bioavailability induced by tunicamycin in HUVECs, C57BJ/6J and PPARδ WT mouse aortas were reversed by paeonol treatment. These beneficial effects of paeonol were diminished in PPARδ knockout (KO) mouse aortas. Paeonol increased the expression of 5' adenosine monophosphate-activated protein kinase (AMPK) and PPARδ expression and activity while restoring the decreased phosphorylation of eNOS. The present study delineates that paeonol protects against tunicamycin-induced vascular endothelial dysfunction by inhibition of ER stress and oxidative stress, thus elevating NO bioavailability via the AMPK/PPARδ signaling pathway.
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Affiliation(s)
- Ker-Woon Choy
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Mohd Rais Mustafa
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Yeh Siang Lau
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Jian Liu
- Institute of Vascular Medicine and Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, China
| | - Dharmani Murugan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Chi Wai Lau
- Institute of Vascular Medicine and Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, China
| | - Li Wang
- Institute of Vascular Medicine and Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, China
| | - Lei Zhao
- Institute of Vascular Medicine and Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, China
| | - Yu Huang
- Institute of Vascular Medicine and Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, China.
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Hu M, Liu B. Resveratrol attenuates lipopolysaccharide-induced dysfunction of blood-brain barrier in endothelial cells via AMPK activation. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2016; 20:325-32. [PMID: 27382348 PMCID: PMC4930900 DOI: 10.4196/kjpp.2016.20.4.325] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 07/08/2015] [Accepted: 01/03/2016] [Indexed: 01/11/2023]
Abstract
Resveratrol, a phytoalexin, is reported to activate AMP-activated protein kinase (AMPK) in vascular cells. The blood-brain barrier (BBB), formed by specialized brain endothelial cells that are interconnected by tight junctions, strictly regulates paracellular permeability to maintain an optimal extracellular environment for brain homeostasis. The aim of this study was to elucidate the effects of resveratrol and the role of AMPK in BBB dysfunction induced by lipopolysaccharide (LPS). Exposure of human brain microvascular endothelial cells (HBMECs) to LPS (1 µg/ml) for 4 to 24 hours week dramatically increased the permeability of the BBB in parallel with lowered expression levels of occluding and claudin-5, which are essential to maintain tight junctions in HBMECs. In addition, LPS significantly increased the reactive oxygen species (ROS) productions. All effects induced by LPS in HBVMCs were reversed by adenoviral overexpression of superoxide dismutase, inhibition of NAD(P) H oxidase by apocynin or gain-function of AMPK by adenoviral overexpression of constitutively active mutant (AMPK-CA) or by resveratrol. Finally, upregulation of AMPK by either AMPK-CA or resveratrol abolished the levels of LPS-enhanced NAD(P)H oxidase subunits protein expressions. We conclude that AMPK activation by resveratrol improves the integrity of the BBB disrupted by LPS through suppressing the induction of NAD(P)H oxidase-derived ROS in HBMECs.
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Affiliation(s)
- Min Hu
- Department of Biomedical Engineering, College of Engineering, Peking University, Beijing 100871, China
| | - Bo Liu
- Deapartment of Orthopaedics, The Third Xiangya Hospital, Central South University, Changsha 410013, China
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64
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Li CY, Erickson SR, Wu CH. Metformin use and asthma outcomes among patients with concurrent asthma and diabetes. Respirology 2016; 21:1210-8. [DOI: 10.1111/resp.12818] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 01/28/2016] [Accepted: 02/22/2016] [Indexed: 01/07/2023]
Affiliation(s)
- Chun-Yi Li
- Medical Affairs; AstraZeneca Taiwan Limited; Taipei Taiwan
| | - Steven R. Erickson
- Department of Clinical, Social and Administrative Sciences, College of Pharmacy; University of Michigan; Ann Arbor Michigan USA
| | - Chung-Hsuen Wu
- School of Pharmacy, College of Pharmacy; Taipei Medical University; Taipei Taiwan
- Research Center for Pharmacoeconomics, College of Pharmacy; Taipei Medical University; Taipei Taiwan
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Zhou Y, Zhang MJ, Li BH, Chen L, Pi Y, Yin YW, Long CY, Wang X, Sun MJ, Chen X, Gao CY, Li JC, Zhang LL. PPARγ Inhibits VSMC Proliferation and Migration via Attenuating Oxidative Stress through Upregulating UCP2. PLoS One 2016; 11:e0154720. [PMID: 27144886 PMCID: PMC4856345 DOI: 10.1371/journal.pone.0154720] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 04/18/2016] [Indexed: 01/20/2023] Open
Abstract
Increasing evidence showed that abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are common event in the pathophysiology of many vascular diseases, including atherosclerosis and restenosis after angioplasty. Among the underlying mechanisms, oxidative stress is one of the principal contributors to the proliferation and migration of VSMCs. Oxidative stress occurs as a result of persistent production of reactive oxygen species (ROS). Recently, the protective effects of peroxisome proliferator-activated receptor γ (PPARγ) against oxidative stress/ROS in other cell types provide new insights to inhibit the suggests that PPARγ may regulate VSMCs function. However, it remains unclear whether activation of PPARγ can attenuate oxidative stress and further inhibit VSMC proliferation and migration. In this study, we therefore investigated the effect of PPARγ on inhibiting VSMC oxidative stress and the capability of proliferation and migration, and the potential role of mitochondrial uncoupling protein 2 (UCP2) in oxidative stress. It was found that platelet derived growth factor-BB (PDGF-BB) induced VSMC proliferation and migration as well as ROS production; PPARγ inhibited PDGF-BB-induced VSMC proliferation, migration and oxidative stress; PPARγ activation upregulated UCP2 expression in VSMCs; PPARγ inhibited PDGF-BB-induced ROS in VSMCs by upregulating UCP2 expression; PPARγ ameliorated injury-induced oxidative stress and intimal hyperplasia (IH) in UCP2-dependent manner. In conclusion, our study provides evidence that activation of PPARγ can attenuate ROS and VSMC proliferation and migration by upregulating UCP2 expression, and thus inhibit IH following carotid injury. These findings suggest PPARγ may represent a prospective target for the prevention and treatment of IH-associated vascular diseases.
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Affiliation(s)
- Yi Zhou
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Ming-Jie Zhang
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Bing-Hu Li
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Lei Chen
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Yan Pi
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Yan-Wei Yin
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Chun-Yan Long
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Xu Wang
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Meng-Jiao Sun
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Xue Chen
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Chang-Yue Gao
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Jing-Cheng Li
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
- * E-mail: (L-LZ); (J-CL)
| | - Li-Li Zhang
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
- * E-mail: (L-LZ); (J-CL)
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66
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Al Disi SS, Anwar MA, Eid AH. Anti-hypertensive Herbs and their Mechanisms of Action: Part I. Front Pharmacol 2016; 6:323. [PMID: 26834637 PMCID: PMC4717468 DOI: 10.3389/fphar.2015.00323] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 12/30/2015] [Indexed: 12/27/2022] Open
Abstract
The use of herbal therapies for treatment and management of cardiovascular diseases (CVDs) is increasing. Plants contain a bounty of phytochemicals that have proven to be protective by reducing the risk of various ailments and diseases. Indeed, accumulating literature provides the scientific evidence and hence reason d'etre for the application of herbal therapy in relation to CVDs. Slowly, but absolutely, herbal remedies are being entrenched into evidence-based medical practice. This is partly due to the supporting clinical trials and epidemiological studies. The rationale for this expanding interest and use of plant based treatments being that a significant proportion of hypertensive patients do not respond to Modern therapeutic medication. Other elements to this equation are the cost of medication, side-effects, accessibility, and availability of drugs. Therefore, we believe it is pertinent to review the literature on the beneficial effects of herbs and their isolated compounds as medication for treatment of hypertension, a prevalent risk factor for CVDs. Our search utilized the PubMed and ScienceDirect databases, and the criterion for inclusion was based on the following keywords and phrases: hypertension, high blood pressure, herbal medicine, complementary and alternative medicine (CAM), nitric oxide, vascular smooth muscle cell (VSMC) proliferation, hydrogen sulfide, nuclear factor kappa-B, oxidative stress, and epigenetics/epigenomics. Each of the aforementioned keywords was co-joined with herb in question, and where possible with its constituent molecule(s). In this first of a two-part review, we provide a brief introduction of hypertension, followed by a discussion of the molecular and cellular mechanisms. We then present and discuss the plants that are most commonly used in the treatment and management of hypertension.
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Affiliation(s)
- Sara S. Al Disi
- Department of Biological and Environmental Sciences, Qatar UniversityDoha, Qatar
| | - M. Akhtar Anwar
- Department of Biological and Environmental Sciences, Qatar UniversityDoha, Qatar
| | - Ali H. Eid
- Department of Biological and Environmental Sciences, Qatar UniversityDoha, Qatar
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of BeirutBeirut, Lebanon
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Inositol-Requiring Enzyme 1-Dependent Activation of AMPK Promotes Brucella abortus Intracellular Growth. J Bacteriol 2016; 198:986-93. [PMID: 26755628 DOI: 10.1128/jb.00868-15] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 01/05/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED AMP-activated protein kinase (AMPK) is a serine/threonine kinase that is well conserved during evolution. AMPK activation inhibits production of reactive oxygen species (ROS) in cells via suppression of NADPH oxidase. However, the role of AMPK during the process of Brucella infection remains unknown. Our data demonstrate that B. abortus infection induces AMPK activation in HeLa cells in a time-dependent manner. The known AMPK kinases LKB1, CAMKKβ, and TAK1 are not required for the activation of AMPK by B. abortus infection. Instead, this activation is dependent on the RNase activity of inositol-requiring enzyme 1 (IRE1). Moreover, we also found that B. abortus infection-induced IRE1-dependent activation of AMPK promotes B. abortus intracellular growth with peritoneal macrophages via suppression of NADPH-derived ROS production. IMPORTANCE Previous studies showed that B. abortus infection does not promote any oxidative burst regulated by NADPH oxidase. However, the underlying mechanism remains elusive. We report for the first time that AMPK activation caused by B. abortus infection plays important role in NADPH oxidase-derived ROS production.
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AMPK in cardiac fibrosis and repair: Actions beyond metabolic regulation. J Mol Cell Cardiol 2016; 91:188-200. [PMID: 26772531 DOI: 10.1016/j.yjmcc.2016.01.001] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 12/28/2015] [Accepted: 01/04/2016] [Indexed: 02/06/2023]
Abstract
Fibrosis is a general term encompassing a plethora of pathologies that span all systems and is marked by increased deposition of collagen. Injury of variable etiology gives rise to complex cascades involving several cell-types and molecular signals, leading to the excessive accumulation of extracellular matrix that promotes fibrosis and eventually leads to organ failure. Cardiac fibrosis is a dynamic process associated notably with ischemia, hypertrophy, volume- and pressure-overload, aging and diabetes mellitus. It has profoundly deleterious consequences on the normal architecture and functioning of the myocardium and is associated with considerable mortality and morbidity. The AMP-activated protein kinase (AMPK) is a ubiquitously expressed cellular energy sensor and an essential component of the adaptive response to cardiomyocyte stress that occurs during ischemia. Nevertheless, its actions extend well beyond its energy-regulating role and it appears to possess an essential role in regulating fibrosis of the myocardium. In this review paper, we will summarize the main elements and crucial players of cardiac fibrosis. In addition, we will provide an overview of the diverse roles of AMPK in the heart and discuss in detail its implication in cardiac fibrosis. Lastly, we will highlight the recently published literature concerning AMPK-targeting current therapy and novel strategies aiming to attenuate fibrosis.
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69
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Ding Y, Chen J, Okon IS, Zou MH, Song P. Absence of AMPKα2 accelerates cellular senescence via p16 induction in mouse embryonic fibroblasts. Int J Biochem Cell Biol 2015; 71:72-80. [PMID: 26718972 DOI: 10.1016/j.biocel.2015.12.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 11/30/2015] [Accepted: 12/18/2015] [Indexed: 01/22/2023]
Abstract
Emerging evidence suggests that activation of adenosine monophosphate-activated protein kinase (AMPK), an energy gauge and redox sensor, delays aging process. However, the molecular mechanisms by which AMPKα isoform regulates cellular senescence remain largely unknown. The aim of this study was to determine if AMPKα deletion contributes to the accelerated cell senescence by inducing p16(INK4A) (p16) expression thereby arresting cell cycle. The markers of cellular senescence, cell cycle proteins, and reactive oxygen species (ROS) were monitored in cultured mouse embryonic fibroblasts (MEFs) isolated from wild type (WT, C57BL/6J), AMPKα1, or AMPKα2 homozygous deficient (AMPKα1(-/-), AMPKα2(-/-)) mice by Western blot and cellular immunofluorescence staining, as well as immunohistochemistry (IHC) in skin tissue of young and aged mice. Deletion of AMPKα2, the minor isoform of AMPKα, but not AMPKα1 in high-passaged MEFs led to spontaneous cell senescence demonstrated by accumulation of senescence-associated-β-galactosidase (SA-β-gal) staining and foci formation of heterochromatin protein 1 homolog gamma (HP1γ). It was shown here that AMPKα2 deletion upregulates cyclin-dependent kinase (CDK) inhibitor, p16, which arrests cell cycle. Furthermore, AMPKα2 null cells exhibited elevated ROS production. Interestingly, knockdown of HMG box-containing protein 1 (HBP1) partially blocked the cellular senescence of AMPKα2-deleted MEFs via the reduction of p16. Finally, dermal cells senescence, including fibroblasts senescence evidenced by the staining of p16, HBP1, and Ki-67, in the skin of aged AMPKα2(-/-) mice was enhanced when compared with that in wild type mice. Taken together, our results suggest that AMPKα2 isoform plays a fundamental role in anti-oxidant stress and anti-senescence.
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Affiliation(s)
- Ye Ding
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA 30303, USA
| | - Jie Chen
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA 30303, USA
| | - Imoh Sunday Okon
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA 30303, USA
| | - Ming-Hui Zou
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA 30303, USA
| | - Ping Song
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA 30303, USA.
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Abstract
Preclinical Research Idiopathic Pulmonary Fibrosis (IPF) is the most severe fibrotic lung disease and characterized by the accumulation of (myo)fibroblasts and collagen within the alveolar wall resulting in obliteration of the gas-exchange surface. Although the detailed pathogenesis is not understood, recent studies have found that several microRNAs (miRNAs) are associated with the progression of lung diseases including IPF. IPF is a fibrotic disease and, most frequently found in an aged population. In this review, the functional roles of miRNAs that are deregulated in IPF progression are discussed together with how aging affects the miRNA signature, altering the fibroblast phenotype and promoting lung fibrosis. Finally, the possibility of targeting miRNAs as a therapeutic approach for the treatment of IPF is discussed.
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71
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Kim GH, Kim JE, Rhie SJ, Yoon S. The Role of Oxidative Stress in Neurodegenerative Diseases. Exp Neurobiol 2015; 24:325-40. [PMID: 26713080 PMCID: PMC4688332 DOI: 10.5607/en.2015.24.4.325] [Citation(s) in RCA: 886] [Impact Index Per Article: 98.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 09/14/2015] [Accepted: 09/14/2015] [Indexed: 12/14/2022] Open
Abstract
Oxidative stress is induced by an imbalanced redox states, involving either excessive generation of reactive oxygen species (ROS) or dysfunction of the antioxidant system. The brain is one of organs especially vulnerable to the effects of ROS because of its high oxygen demand and its abundance of peroxidation-susceptible lipid cells. Previous studies have demonstrated that oxidative stress plays a central role in a common pathophysiology of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Antioxidant therapy has been suggested for the prevention and treatment of neurodegenerative diseases, although the results with regard to their efficacy of treating neurodegenerative disease have been inconsistent. In this review, we will discuss the role of oxidative stress in the pathophysiology of neurodegenerative diseases and in vivo measurement of an index of damage by oxidative stress. Moreover, the present knowledge on antioxidant in the treatment of neurodegenerative diseases and future directions will be outlined.
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Affiliation(s)
- Geon Ha Kim
- Ewha Brain Institute, Ewha Womans University, Seoul 03760, Korea. ; Department of Neurology, Ewha Womans University Mokdong Hospital, Ewha Womans University School of Medicine, Seoul 03760, Korea
| | - Jieun E Kim
- Ewha Brain Institute, Ewha Womans University, Seoul 03760, Korea. ; Department of Brain and Cognitive Sciences, Ewha Womans University, Seoul 03760, Korea
| | - Sandy Jeong Rhie
- Ewha Brain Institute, Ewha Womans University, Seoul 03760, Korea. ; College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 03760, Korea
| | - Sujung Yoon
- Ewha Brain Institute, Ewha Womans University, Seoul 03760, Korea
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Lycopene Protects against Hypoxia/Reoxygenation Injury by Alleviating ER Stress Induced Apoptosis in Neonatal Mouse Cardiomyocytes. PLoS One 2015; 10:e0136443. [PMID: 26291709 PMCID: PMC4546295 DOI: 10.1371/journal.pone.0136443] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 08/03/2015] [Indexed: 12/12/2022] Open
Abstract
Endoplasmic reticulum (ER) stress induced apoptosis plays a pivotal role in myocardial ischemia/reperfusion (I/R)-injury. Inhibiting ER stress is a major therapeutic target/strategy in treating cardiovascular diseases. Our previous studies revealed that lycopene exhibits great pharmacological potential in protecting against the I/R-injury in vitro and vivo, but whether attenuation of ER stress (and) or ER stress-induced apoptosis contributes to the effects remains unclear. In the present study, using neonatal mouse cardiomyocytes to establish an in vitro model of hypoxia/reoxygenation (H/R) to mimic myocardium I/R in vivo, we aimed to explore the hypothesis that lycopene could alleviate the ER stress and ER stress-induced apoptosis in H/R-injury. We observed that lycopene alleviated the H/R injury as revealed by improving cell viability and reducing apoptosis, suppressed reactive oxygen species (ROS) generation and improved the phosphorylated AMPK expression, attenuated ER stress as evidenced by decreasing the expression of GRP78, ATF6 mRNA, sXbp-1 mRNA, eIF2α mRNA and eIF2α phosphorylation, alleviated ER stress-induced apoptosis as manifested by reducing CHOP/GADD153 expression, the ratio of Bax/Bcl-2, caspase-12 and caspase-3 activity in H/R-treated cardiomyocytes. Thapsigargin (TG) is a potent ER stress inducer and used to elicit ER stress of cardiomyocytes. Our results showed that lycopene was able to prevent TG-induced ER stress as reflected by attenuating the protein expression of GRP78 and CHOP/GADD153 compared to TG group, significantly improve TG-caused a loss of cell viability and decrease apoptosis in TG-treated cardiomyocytes. These results suggest that the protective effects of lycopene on H/R-injury are, at least in part, through alleviating ER stress and ER stress-induced apoptosis in neonatal mouse cardiomyocytes.
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Tang H, Pan CS, Mao XW, Liu YY, Yan L, Zhou CM, Fan JY, Zhang SY, Han JY. Role of NADPH oxidase in total salvianolic acid injection attenuating ischemia-reperfusion impaired cerebral microcirculation and neurons: implication of AMPK/Akt/PKC. Microcirculation 2015; 21:615-27. [PMID: 24702968 DOI: 10.1111/micc.12140] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 04/02/2014] [Indexed: 11/30/2022]
Abstract
OBJECTIVE TSI is a new drug derived from Chinese medicine for treatment of ischemic stroke in China. The aim of this study was to verify the therapeutic effect of TSI in a rat model of MCAO, and further explore the mechanism for its effect. METHODS Male Sprague-Dawley rats were subjected to right MCAO for 60 minutes followed by reperfusion. TSI (1.67 mg/kg) was administrated before reperfusion via femoral vein injection. Twenty-four hours after reperfusion, the fluorescence intensity of DHR 123 in, leukocyte adhesion to and albumin leakage from the cerebral venules were observed. Neurological scores, TTC staining, brain water content, Nissl staining, TUNEL staining, and MDA content were assessed. Bcl-2/Bax, cleaved caspase-3, NADPH oxidase subunits p47(phox)/p67(phox)/gp91(phox), and AMPK/Akt/PKC were analyzed by Western blot. RESULTS TSI attenuated I/R-induced microcirculatory disturbance and neuron damage, activated AMPK, inhibited NADPH oxidase subunits membrane translocation, suppressed Akt phosphorylation, and PKC translocation. CONCLUSIONS TSI attenuates I/R-induced brain injury in rats, supporting its clinic use for treatment of acute ischemic stroke. The role of TSI may benefit from its antioxidant activity, which is most likely implemented via inactivation of NADPH oxidase through a signaling pathway implicating AMPK/Akt/PKC.
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Affiliation(s)
- Hao Tang
- The Fourth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
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Bi X, He X, Xu M, Zhao M, Yu X, Lu X, Zang W. Acetylcholine ameliorates endoplasmic reticulum stress in endothelial cells after hypoxia/reoxygenation via M3 AChR-AMPK signaling. Cell Cycle 2015; 14:2461-72. [PMID: 26066647 DOI: 10.1080/15384101.2015.1060383] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Endoplasmic reticulum (ER) stress is associated with various cardiovascular diseases. However, its pathophysiological relevance and the underlying mechanisms in the context of hypoxia/reoxygenation (H/R) in endothelial cells are not fully understood. Previous findings have suggested that acetylcholine (ACh), the major vagal nerve neurotransmitter, protected against cardiomyocyte injury by activating AMP-activated protein kinase (AMPK). This study investigated the role of ER stress in endothelial cells during H/R and explored the beneficial effects of ACh. Our results showed that H/R triggered ER stress and apoptosis in endothelial cells, evidenced by the elevation of glucose-regulated protein 78, cleaved caspase-12 and C/EBP homologous protein expression. ACh significantly decreased ER stress and terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling positive cells and restored ER ultrastructural changes induced by H/R, possibly via protein kinase-like ER kinase and inositol-requiring kinase 1 pathways. Additionally, 4-diphenylacetoxy-N-methylpiperidine methiodide, a type-3 muscarinic ACh receptor (M3 AChR) inhibitor, abolished ACh-mediated increase in AMPK phosphorylation during H/R. Furthermore, M3 AChR or AMPK siRNA abrogated the ACh-elicited the attenuation of ER stress in endothelial cells, indicating that the salutary effects of ACh were likely mediated by M3 AChR-AMPK signaling. Overall, ACh activated AMPK through M3 AChR, thereby inhibited H/R-induced ER stress and apoptosis in endothelial cells. We have suggested for the first time that AMPK may function as an essential intermediate step between M3 AChR stimulation and inhibition of ER stress-associated apoptotic pathway during H/R, which may help to develop novel therapeutic approaches targeting ER stress to prevent or alleviate ischemia/reperfusion injury.
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Key Words
- 4-DAMP, 4-diphenylacetoxy-N-methylpiperidine methiodide
- 4-PBA, 4-phenyl butyric acid
- ACh, acetylcholine
- AMPK
- AMPK, AMP-activated protein kinase
- ATF6, activating transcription factor 6
- CHOP, C/EBP homologous protein
- DAPI, 4′,6-diamidino-2-phenylindole
- ER, endoplasmic reticulum
- GAPDH, glyceraldehyde 3-phospharte dehydrogenase
- GRP78, glucose-regulated protein 78
- H/R, hypoxia/reoxygenation
- I/R, ischemia/reperfusion
- IRE1, inositol-requiring kinase 1
- M3 AChR
- MAChR, muscarinic acetylcholine receptor
- PBS, phosphate-buffered saline
- PERK, protein kinase-like ER kinase
- TUNEL, terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling
- acetylcholine
- apoptosis
- endoplasmic reticulum stress
- endothelial cells
- ischemia/reperfusion injury
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Affiliation(s)
- Xueyuan Bi
- a Department of Pharmacology ; Xi'an Jiaotong University Health Science Center , Xi'an , P.R. China
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Herbal SGR Formula Prevents Acute Ethanol-Induced Liver Steatosis via Inhibition of Lipogenesis and Enhancement Fatty Acid Oxidation in Mice. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:613584. [PMID: 26101535 PMCID: PMC4458561 DOI: 10.1155/2015/613584] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 04/06/2015] [Accepted: 04/06/2015] [Indexed: 02/06/2023]
Abstract
Our previous study indicated that herbal SGR formula partially attenuates ethanol-induced fatty liver, but the underlying mechanisms remain unclear. In the present study, mice were pretreated with SGR (100 and 200 mg/kg/d bw) for 30 d before being exposed to ethanol (4.8 g/kg bw). The biochemical indices and histopathological changes were examined to evaluate the protective effects and to explore potential mechanisms by investigating the adiponectin, tumor necrosis factor-α (TNF-α), peroxisome proliferators-activated receptor-α (PPAR-α), sterol regulatory element binding protein-1c (SREBP-1c), adenosine monophosphate-activated protein kinase (AMPK), and so forth. Results showed that SGR pretreatment markedly inhibited acute ethanol-induced liver steatosis, significantly reduced serum and hepatic triglyceride (TG) level, and improved classic histopathological changes. SGR suppressed the protein expression of hepatic SREBP-1c and TNF-α and increased adiponectin, PPAR-α, and AMPK phosphorylation in the liver. Meanwhile, acute toxicity tests showed that no death or toxic side effects within 14 days were observed upon oral administration of the extracts at a dose of 16 g/kg body wt. These results demonstrate that SGR could protect against acute alcohol-induced liver steatosis without any toxic side effects. Therefore, our studies provide novel molecular insights into the hepatoprotective effect of SGR formula, which may be exploited as a therapeutic agent for ethanol-induced hepatosteatosis.
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Yu HY, Cai YB, Liu Z. Activation of AMPK improves lipopolysaccharide-induced dysfunction of the blood–brain barrier in mice. Brain Inj 2015; 29:777-84. [DOI: 10.3109/02699052.2015.1004746] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
| | - Yu-Bing Cai
- Department of Otorhinolaryngology, The People’s Hospital of Xishui, Huang-Gang, Hubei, PR China, and
| | - Zhan Liu
- Department of Neurology,
- Department of Gastroenterology, People’s Hospital of Hunan Province, Hunan Normal University, Changsha, Hunan, PR China
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78
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Lin MC, Ou TT, Chang CH, Chan KC, Wang CJ. Protocatechuic acid inhibits oleic acid-induced vascular smooth muscle cell proliferation through activation of AMP-activated protein kinase and cell cycle arrest in G0/G1 phase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:235-241. [PMID: 25513741 DOI: 10.1021/jf505303s] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Protocatechuic acid (PCA) has been implicated in the progression of atherosclerosis. The proliferation of vascular smooth muscle cells (VSMC) may play a crucial role in the pathogenesis of atherosclerosis. Adenosine 5′-monophosphate-activated protein kinase (AMPK) additionally exerts several beneficial effects on vascular function and improves vascular abnormalities. The current study sought to determine whether PCA has an inhibitory effect on VSMC proliferation under oleic acid (OA) treatment. A7r5 cells were treated with OA (150 μM) or cotreated with OA and PCA (150 μg/mL) for 24 and 48 h. PCA-treated cells were found to cause an increase in G0/G1 cell cycle arrest. Western blotting showed that PCA increased the expressions of p53 and p21Cip1, subsequently decreasing the expression of cyclin E1 and Cdk2. In addition, PCA induced phosphorylation of AMPK and inhibited the expression of fatty acid synthase, Akt-p, and Skp2 after stimulation with OA. After treatment with AMPK inhibitor, the effects of PCA mentioned above were reversed. Taken together, PCA inhibited OA-induced VSMC proliferation through AMPK activation and down-regulation of FAS and AKT signals, which then blocks G0/G1 phase cell cycle progression. These findings provide a new insight into the protective properties of PCA on VSMC, which may constitute a novel effective antiatherosclerosis agent.
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79
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Activation of AMPK attenuates lipopolysaccharide-impaired integrity and function of blood–brain barrier in human brain microvascular endothelial cells. Exp Mol Pathol 2014; 97:386-92. [DOI: 10.1016/j.yexmp.2014.09.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 08/27/2014] [Accepted: 09/10/2014] [Indexed: 12/27/2022]
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80
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Xu H, Zhou Y, Coughlan KA, Ding Y, Wang S, Wu Y, Song P, Zou MH. AMPKα1 deficiency promotes cellular proliferation and DNA damage via p21 reduction in mouse embryonic fibroblasts. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:65-73. [PMID: 25307521 DOI: 10.1016/j.bbamcr.2014.10.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 09/22/2014] [Accepted: 10/01/2014] [Indexed: 10/24/2022]
Abstract
Emerging evidence suggests that activation of adenosine monophosphate-activated protein kinase (AMPK), an energy gauge and redox sensor, controls the cell cycle and protects against DNA damage. However, the molecular mechanisms by which AMPKα isoform regulates DNA damage remain largely unknown. The aim of this study was to determine if AMPKα deletion contributes to cellular hyperproliferation by reducing p21(WAF1/Cip1) (p21) expression thereby leading to accumulated DNA damage. The markers for DNA damage, cell cycle proteins, and apoptosis were monitored in cultured mouse embryonic fibroblasts (MEFs) isolated from wild type (WT, C57BL/6J), AMPKα1, or AMPKα2 homozygous deficient (AMPKα1(-/-), AMPKα2(-/-)) mice by Western blot, flow cytometry, and cellular immunofluorescence staining. Deletion of AMPKα1, the predominant AMPKα isoform, but not AMPKα2 in immortalized MEFs led to spontaneous DNA double-strand breaks (DSB) which corresponded to repair protein p53-binding protein 1 (53BP1) foci formation and subsequent apoptosis. Furthermore, AMPKα1 localizes to chromatin and AMPKα1 deletion down-regulates cyclin-dependent kinase inhibitor, p21, an important protein that plays a role in decreasing the incidence of spontaneous DSB via inhibition of cell proliferation. In addition, AMPKα1 null cells exhibited enhanced cell proliferation. Finally, p21 overexpression partially blocked the cellular hyperproliferation of AMPKα1-deleted MEFs via the inhibition of cyclin-dependent kinase 2 (CDK2). Taken together, our results suggest that AMPKα1 plays a fundamental role in controlling the cell cycle thereby affecting DNA damage and cellular apoptosis.
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Affiliation(s)
- Hairong Xu
- Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; School of Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, China
| | - Yanhong Zhou
- Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; Key Laboratory of Hubei Province on Cardio-Cerebral Diseases, Hubei University of Science and Technology, Xianning, Hubei, China
| | - Kathleen A Coughlan
- Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Ye Ding
- Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Shaobin Wang
- Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Yue Wu
- Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Ping Song
- Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
| | - Ming-Hui Zou
- Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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81
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Anwar MA, Kheir WA, Eid S, Fares J, Liu X, Eid AH, Eid AA. Colorectal and Prostate Cancer Risk in Diabetes: Metformin, an Actor behind the Scene. J Cancer 2014; 5:736-44. [PMID: 25368673 PMCID: PMC4216797 DOI: 10.7150/jca.9726] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Accepted: 08/13/2014] [Indexed: 02/06/2023] Open
Abstract
Both diabetes and cancer are prevalent diseases whose incidence rates are increasing worldwide, especially in countries that are undergoing rapid industrialization changes. Apparently, lifestyle risk factors including diet, physical inactivity and obesity play pivotal, yet preventable, roles in the etiology of both diseases. Epidemiological studies provide strong evidence that subjects with diabetes are at significantly higher risk of developing many forms of cancer and especially solid tumors. In addition to pancreatic and breast cancer, the incidence of colorectal cancer and prostate cancer is increased in type 2 diabetes. While diabetes (type 2) and cancer share many risk factors, the biological links between the two diseases are poorly characterized. In this review, we highlight the mechanistic pathways that link diabetes to colorectal and prostate cancer and the use of Metformin, a diabetes drug, to prevent and/or treat colorectal and prostate cancer. We review the role of AMPK activation in autophagy, oxidative stress, inflammation, apoptosis, and cell cycle progression.
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Affiliation(s)
- M Akhtar Anwar
- 1. Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha - Qatar
| | - Wassim Abou Kheir
- 2. Department of Anatomy, Cell Biology and Physiology, Faculty of Medicine, American University of Beirut, Beirut - Lebanon and
| | - Stephanie Eid
- 2. Department of Anatomy, Cell Biology and Physiology, Faculty of Medicine, American University of Beirut, Beirut - Lebanon and
| | - Joanna Fares
- 2. Department of Anatomy, Cell Biology and Physiology, Faculty of Medicine, American University of Beirut, Beirut - Lebanon and
| | - Xiaoqi Liu
- 3. Department of Biochemistry, Purdue University
| | - Ali H Eid
- 1. Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha - Qatar
| | - Assaad A Eid
- 2. Department of Anatomy, Cell Biology and Physiology, Faculty of Medicine, American University of Beirut, Beirut - Lebanon and
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82
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Protective effect of vitexin compound B-1 against hypoxia/reoxygenation-induced injury in differentiated PC12 cells via NADPH oxidase inhibition. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2014; 387:861-71. [DOI: 10.1007/s00210-014-1006-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 06/06/2014] [Indexed: 10/25/2022]
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83
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Zhao W, Zhou S, Yao W, Gan X, Su G, Yuan D, Hei Z. Propofol prevents lung injury after intestinal ischemia-reperfusion by inhibiting the interaction between mast cell activation and oxidative stress. Life Sci 2014; 108:80-7. [PMID: 24878149 DOI: 10.1016/j.lfs.2014.05.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 04/19/2014] [Accepted: 05/13/2014] [Indexed: 12/22/2022]
Abstract
AIMS Both mast cells and oxidative stress are involved in acute lung injury (ALI) induced by intestinal ischemia-reperfusion (IIR). The aim of this study was to investigate whether propofol could improve IIR-induced ALI through inhibiting their interaction. MAIN METHODS Repetitive, brief IIR or IIR+compound 48/80 was performed in adult Sprague-Dawley rats pretreated with saline, apocynin or propofol. And their lungs were excised for histology, ELISA and protein-expression measurements 2h after reperfusion. KEY FINDINGS Rats pretreated with saline developed critical ALI 2h after IIR. We found significant elevations in lung injury scores, lung wet/dry ratio and gp91phox, p47phox, intercellular cell adhesion molecule-1 protein expressions and higher level of malondialdehyde, interleukin-6 contents, and myeloperoxidase activities, as well as significant reductions in superoxide dismutase activities, accompanied with increases in mast cell degranulation evidenced by significant increases in mast cell counts, β-hexosaminidase concentrations, and tryptase expression. And the lung injury was aggravated in the presence of compound 48/80. However, pretreated with propofol and apocynin not only ameliorated the IIR-mediated pulmonary changes beyond the biochemical changes but also reversed the changes that were aggravated by compound 48/80. SIGNIFICANCE Propofol protects against IIR-mediated ALI, most likely by inhibiting the interaction between oxidative stress and mast cell degranulation.
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Affiliation(s)
- Weicheng Zhao
- Department of Anesthesiology, The First People's Hospital of Foshan, 81 North of Rinlan Road, Foshan 528000, China; Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China
| | - Shaoli Zhou
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China
| | - Weifeng Yao
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China
| | - Xiaoliang Gan
- Department of Anesthesiology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 South of Xianlie Road, Guangzhou 510060, China
| | - Guangjie Su
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China
| | - Dongdong Yuan
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China
| | - Ziqing Hei
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China.
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84
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Mitochondrial regulation of NADPH oxidase in hindlimb unweighting rat cerebral arteries. PLoS One 2014; 9:e95916. [PMID: 24759683 PMCID: PMC3997512 DOI: 10.1371/journal.pone.0095916] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 04/01/2014] [Indexed: 02/07/2023] Open
Abstract
Exposure to microgravity results in post-flight cardiovascular deconditioning and orthostatic intolerance in astronauts. Vascular oxidative stress injury and mitochondrial dysfunction have been indicated in this process. To elucidate the mechanism for this condition, we investigated whether mitochondria regulated NADPH oxidase in hindlimb unweighting (HU) rat cerebral and mesenteric arteries. Four-week HU was used to simulate microgravity in rats. Vascular superoxide generation, protein and mRNA levels of Nox2/Nox4, and the activity of NADPH oxidase were examined in the present study. Compared with control rats, the levels of superoxide increased in cerebral (P<0.001) but not in mesenteric vascular smooth muscle cells. The protein and mRNA levels of Nox2 and Nox4 were upregulated significantly (P<0.001 and P<0.001 for Nox2, respectively; P<0.001 and P<0.001 for Nox4, respectively) in HU rat cerebral arteries but not in mesenteric arteries. NADPH oxidases were activated significantly by HU (P<0.001) in cerebral arteries but not in mesenteric arteries. Chronic treatment with mitochondria-targeted antioxidant mitoTEMPO attenuated superoxide levels (P<0.001), decreased the protein and mRNA expression levels of Nox2/Nox4 (P<0.01 and P<0.05 for Nox2, respectively; P<0.001 and P<0.001 for Nox4, respectively) and the activity of NADPH oxidase (P<0.001) in HU rat cerebral arteries, but exerted no effects on HU rat mesenteric arteries. Therefore, mitochondria regulated the expression and activity of NADPH oxidases during simulated microgravity. Both mitochondria and NADPH oxidase participated in vascular redox status regulation.
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85
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Zhao W, Gan X, Su G, Wanling G, Li S, Hei Z, Yang C, Wang H. The interaction between oxidative stress and mast cell activation plays a role in acute lung injuries induced by intestinal ischemia–reperfusion. J Surg Res 2014; 187:542-52. [DOI: 10.1016/j.jss.2013.10.033] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2013] [Revised: 10/01/2013] [Accepted: 10/17/2013] [Indexed: 11/26/2022]
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86
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Song P, Zou MH. Redox regulation of endothelial cell fate. Cell Mol Life Sci 2014; 71:3219-39. [PMID: 24633153 DOI: 10.1007/s00018-014-1598-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 02/26/2014] [Accepted: 02/27/2014] [Indexed: 12/26/2022]
Abstract
Endothelial cells (ECs) are present throughout blood vessels and have variable roles in both physiological and pathological settings. EC fate is altered and regulated by several key factors in physiological or pathological conditions. Reactive nitrogen species and reactive oxygen species derived from NAD(P)H oxidases, mitochondria, or nitric oxide-producing enzymes are not only cytotoxic but also compose a signaling network in the redox system. The formation, actions, key molecular interactions, and physiological and pathological relevance of redox signals in ECs remain unclear. We review the identities, sources, and biological actions of oxidants and reductants produced during EC function or dysfunction. Further, we discuss how ECs shape key redox sensors and examine the biological functions, transcriptional responses, and post-translational modifications evoked by the redox system in ECs. We summarize recent findings regarding the mechanisms by which redox signals regulate the fate of ECs and address the outcome of altered EC fate in health and disease. Future studies will examine if the redox biology of ECs can be targeted in pathophysiological conditions.
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Affiliation(s)
- Ping Song
- Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, 941 Stanton L Young Blvd., Oklahoma City, OK, 73104, USA,
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87
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Corradi F, Paolini L, De Caterina R. Ranolazine in the prevention of anthracycline cardiotoxicity. Pharmacol Res 2014; 79:88-102. [DOI: 10.1016/j.phrs.2013.11.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Revised: 11/06/2013] [Accepted: 11/06/2013] [Indexed: 12/19/2022]
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88
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Zhao WC, Zhang B, Liao MJ, Zhang WX, He WY, Wang HB, Yang CX. Curcumin ameliorated diabetic neuropathy partially by inhibition of NADPH oxidase mediating oxidative stress in the spinal cord. Neurosci Lett 2013; 560:81-5. [PMID: 24370596 DOI: 10.1016/j.neulet.2013.12.019] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 11/16/2013] [Accepted: 12/10/2013] [Indexed: 11/28/2022]
Abstract
Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases are the main enzymes that produce oxidative stress, which plays an important role in painful diabetic neuropathy. Curcumin has been reported to exert an antinociceptive effect in a rat model of diabetic neuropathy by suppressing oxidative stress in the spinal cord. However, it remains unknown whether the mechanism by which curcumin ameliorates diabetic neuropathy can be attributed to spinal NADPH oxidases. This study was designed to determine the effect of curcumin on diabetic neuropathy and to investigate its precise mechanism in relation to NADPH oxidase-mediating oxidative stress in the spinal cord. Diabetic neuropathy was induced in Sprague-Dawley rats by intraperitoneal injection with 1% streptozotocin (STZ; 60 mg/kg). After the onset of diabetic neuropathy, a subset of the diabetic rats received daily intragastric administrations of curcumin (200mg/kg) or intraperitoneal injections of apocynin (2.5mg/kg) for 14 consecutive days, whereas other diabetic rats received equivalent volumes of normal saline (NS). STZ resulted in diabetic neuropathy with hyperglycemia and a lower paw withdrawal threshold (PWT), accompanied by elevations in the expression of the NADPH oxidase subunits p47(phox) and gp91(phox) and in the levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA) and a reduction in superoxide dismutase (SOD) activity (P<0.05) in the spinal cord. Both curcumin and apocynin ameliorated diabetic neuropathy. In conclusion, curcumin attenuated neuropathic pain in diabetic rats, at least partly by inhibiting NADPH oxidase-mediating oxidative stress in the spinal cord.
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Affiliation(s)
- Wei-Cheng Zhao
- Department of Anesthesiology, The First People's Hospital of Foshan, 81# North of Rinlan Road, Foshan 528000, China
| | - Bin Zhang
- Department of Anesthesiology, The First People's Hospital of Foshan, 81# North of Rinlan Road, Foshan 528000, China
| | - Mei-Juan Liao
- Department of Anesthesiology, The First People's Hospital of Foshan, 81# North of Rinlan Road, Foshan 528000, China
| | - Wen-Xuan Zhang
- Department of Anesthesiology, The First People's Hospital of Foshan, 81# North of Rinlan Road, Foshan 528000, China
| | - Wan-You He
- Department of Anesthesiology, The First People's Hospital of Foshan, 81# North of Rinlan Road, Foshan 528000, China
| | - Han-Bing Wang
- Department of Anesthesiology, The First People's Hospital of Foshan, 81# North of Rinlan Road, Foshan 528000, China
| | - Cheng-Xiang Yang
- Department of Anesthesiology, The First People's Hospital of Foshan, 81# North of Rinlan Road, Foshan 528000, China.
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89
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Berberine protects against palmitate-induced endothelial dysfunction: involvements of upregulation of AMPK and eNOS and downregulation of NOX4. Mediators Inflamm 2013; 2013:260464. [PMID: 24385682 PMCID: PMC3872165 DOI: 10.1155/2013/260464] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 09/12/2013] [Accepted: 11/10/2013] [Indexed: 01/11/2023] Open
Abstract
Endothelial dysfunction is a critical factor during the initiation of cardiovascular complications in diabetes. Berberine can ameliorate endothelial dysfunction induced by diabetes. However, the underlying mechanisms remain unclear. The aim of this study was to investigate the protective effect and mechanism of berberine on palmitate-induced endothelial dysfunction in human umbilical vein endothelial cells (HUVECs). The cell viability of HUVECs was determined by MTT assays. Nitric oxide (NO) level and production of reactive oxygen species (ROS) were determined in supernatants or in the cultured HUVECs. The mRNA level of endothelial nitric oxide synthase (eNOS) was measured by RT-PCR, and the protein levels of eNOS, p-eNOS, Akt, p-Akt, AMPK, p-AMPK, and NADPH oxidase (NOX4) were analyzed. The results demonstrated that berberine significantly elevated NO levels and reduced the production of ROS. The expressions of eNOS were significantly increased, while NOX4 protein expression was decreased in berberine-treated HUVECs. Moreover, berberine upregulated the protein expression of AMPK and p-AMPK in palmitate-treated HUVECs, but had no effect on the levels of Akt. Therefore, berberine ameliorates palmitate-induced endothelial dysfunction by upregulating eNOS expression and downregulating expression of NOX4. This regulatory effect of berberine may be related to the activation of AMPK.
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90
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Song P, Zhou Y, Coughlan KA, Dai X, Xu H, Viollet B, Zou MH. Adenosine monophosphate-activated protein kinase-α2 deficiency promotes vascular smooth muscle cell migration via S-phase kinase-associated protein 2 upregulation and E-cadherin downregulation. Arterioscler Thromb Vasc Biol 2013; 33:2800-9. [PMID: 24115035 DOI: 10.1161/atvbaha.113.301869] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are critical events in the progression of several vasculopathologies. Adenosine monophosphate-activated protein kinase (AMPK) has been shown to play a pivotal role in cellular proliferation and migration. However, the roles of AMPK in VSMC migration and its underlying molecular mechanisms remain elusive. APPROACH AND RESULTS VSMC migration and the neointima formation were studied in cultured mouse VSMCs or in carotid artery ligation of wild-type C57BL/6J mice, AMPKα2, AMPKα1 homozygous-deficient (AMPKα2(-/-), AMPKα1(-/-)) mice. Deletion of AMPKα2, but not AMPKα1, led to increased phosphorylation of both IкB kinase α and its downstream target nuclear factor кB2/p100 at serine 866/870. Consequently, phosphor-p100 at S866/870 bound with E3 ubiquitin ligase β-transducin repeat-containing protein resulting in the proteolytic processing of the p100 precursor and nuclear factor кB2/p52 induction. Interestingly, acetylation of histone H3 at lysine 56 mediated by histone deacetylase-3 reduction was enhanced significantly in AMPKα2(-/-) VSMCs compared with wild-type or AMPKα1(-/-) VSMCs. Moreover, the augmented association of p52/acetylation of histone H3 at lysine 56 with the promoter of ubiquitin E3 ligase, S-phase kinase-associated protein 2, was shown in AMPKα2(-/-) VSMCs by chromatin immunoprecipitation assay. Furthermore, AMPKα2 deletion caused S-phase kinase-associated protein 2-mediated E-cadherin downregulation. S-Phase kinase-associated protein 2 siRNA abolished the increased migration of AMPKα2(-/-) VSMCs via E-cadherin upregulation. Finally, neointima formation after ligation of carotid artery was increased in AMPKα2(-/-), but not AMPKα1(-/-), mice. CONCLUSIONS We conclude that deletion of AMPKα2 causes aberrant VSMC migration with accelerated neointima formation in vivo.
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Affiliation(s)
- Ping Song
- From the Section of Molecular Medicine, Department of Internal Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK (P.S., Y.Z., K.A.C., X.D., H.X., M.-H.Z.); College of Medicine, Hubei, Province Key Laboratory on Cardiovascular, Cerebrovascular, and Metabolic Disorders, Hubei University of Science and Technology, Xianning, Hubei, China (Y.Z.); College of Medicine, Yangzhou University, Yangzhou, Jiangsu, China (H.X.); Institut Cochin, Université Paris Descartes, CNRS (UMR 8104), Paris, France (B.V.); and INSERM, U1016, Paris, France (B.V.)
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91
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Zhang X, Zhu P, Zhang X, Ma Y, Li W, Chen JM, Guo HM, Bucala R, Zhuang J, Li J. Natural antioxidant-isoliquiritigenin ameliorates contractile dysfunction of hypoxic cardiomyocytes via AMPK signaling pathway. Mediators Inflamm 2013; 2013:390890. [PMID: 24163504 PMCID: PMC3791876 DOI: 10.1155/2013/390890] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 08/14/2013] [Indexed: 12/27/2022] Open
Abstract
Isoliquiritigenin (ISL), a simple chalcone-type flavonoid, is derived from licorice compounds and is mainly present in foods, beverages, and tobacco. Reactive oxygen species (ROS) is a critical factor involved in modulating cardiac stress response signaling during ischemia and reperfusion. We hypothesize that ISL as a natural antioxidant may protect heart against ischemic injury via modulating cellular redox status and regulating cardioprotective signaling pathways. The fluorescent probe H2DCFDA was used to measure the level of intracellular ROS. The glucose uptake was determined by 2-deoxy-D-glucose-(3)H accumulation. The IonOptix System measured the contractile function of isolated cardiomyocytes. The results demonstrated that ISL treatment markedly ameliorated cardiomyocytes contractile dysfunction caused by hypoxia. ISL significantly stimulated cardioprotective signaling, AMP-activated protein kinase (AMPK), and extracellular signal-regulated kinase (ERK) signaling pathways. The ROS fluorescent probe H2DCFDA determination indicated that ISL significantly reduced cardiac ROS level during hypoxia/reoxygenation. Moreover, ISL reduced the mitochondrial potential (Δψ) of isolated mouse cardiomyocytes. Taken together, ISL as a natural antioxidant demonstrated the cardioprotection against ischemic injury that may attribute to the activation of AMPK and ERK signaling pathways and balance of cellular redox status.
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Affiliation(s)
- Xiaoyu Zhang
- Institute of Physiology, School of Basic Medicine Sciences, Lanzhou University, Lanzhou 730000, China
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo-SUNY University of New York, Buffalo, NY 14214, USA
| | - Ping Zhu
- Department of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
| | - Xiuying Zhang
- Department of Emergency, Gansu Provincial Hospital, Lanzhou 730000, China
| | - Yina Ma
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo-SUNY University of New York, Buffalo, NY 14214, USA
| | - Wenguang Li
- Institute of Physiology, School of Basic Medicine Sciences, Lanzhou University, Lanzhou 730000, China
| | - Ji-Mei Chen
- Department of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
| | - Hui-Ming Guo
- Department of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
| | - Richard Bucala
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Jian Zhuang
- Department of Cardiovascular Surgery, Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
| | - Ji Li
- Department of Pharmacology and Toxicology, School of Medicine and Biomedical Sciences, University at Buffalo-SUNY University of New York, Buffalo, NY 14214, USA
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92
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Inhibition of reactive oxygen species generation attenuates TLR4-mediated proinflammatory and proliferative phenotype of vascular smooth muscle cells. J Transl Med 2013; 93:880-7. [PMID: 23774581 DOI: 10.1038/labinvest.2013.79] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 04/27/2013] [Accepted: 05/20/2013] [Indexed: 02/03/2023] Open
Abstract
Reactive oxygen species (ROS) are associated with inflammation and vasculature dysfunction. This study aimed to investigate the potential role of the ROS on vascular Toll-like receptor 4 (TLR4)-mediated proinflammatory and proliferative phenotype of vascular smooth muscle cells (VSMCs). A wire-induced carotid injury model was used in male TLR4-deficient (TLR4(-/-)) and wild-type C57BL/6J mice to induce neointima formation. In the presence or absence of the ROS scavenger apocynin for 14 days, increased TLR4 and proinflammatory cytokines were observed in wire injury-induced carotid neointima and in platelet-derived growth factor-BB (PDGF-BB)-stimulated VSMCs. The TLR4(-/-) protected the injured carotid from neointimal formation and impaired the cellular proliferation and migration in response to PDGF-BB. Apocynin attenuated intimal hyperplasia. Pre-treatment with apocynin significantly inhibited intracellular ROS generation, accompanied by a significant suppression of TLR4 and proinflammatory cytokines expression, and VSMC proliferation and migration. However, the results were not obvious in TLR4(-/-) condition. These findings highlight the importance of ROS inhibition in TLR4-mediated proinflammatory and proliferative phenotype of VSMCs, and suggest ROS as an essential therapeutic target for TLR4-associated vascular inflammation and vascular diseases.
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93
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Sestrin 2 and AMPK connect hyperglycemia to Nox4-dependent endothelial nitric oxide synthase uncoupling and matrix protein expression. Mol Cell Biol 2013; 33:3439-60. [PMID: 23816887 DOI: 10.1128/mcb.00217-13] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Mesangial matrix accumulation is an early feature of glomerular pathology in diabetes. Oxidative stress plays a critical role in hyperglycemia-induced glomerular injury. Here, we demonstrate that, in glomerular mesangial cells (MCs), endothelial nitric oxide synthase (eNOS) is uncoupled upon exposure to high glucose (HG), with enhanced generation of reactive oxygen species (ROS) and decreased production of nitric oxide. Peroxynitrite mediates the effects of HG on eNOS dysfunction. HG upregulates Nox4 protein, and inhibition of Nox4 abrogates the increase in ROS and peroxynitrite generation, as well as the eNOS uncoupling triggered by HG, demonstrating that Nox4 functions upstream from eNOS. Importantly, this pathway contributes to HG-induced MC fibronectin accumulation. Nox4-mediated eNOS dysfunction was confirmed in glomeruli of a rat model of type 1 diabetes. Sestrin 2-dependent AMP-activated protein kinase (AMPK) activation attenuates HG-induced MC fibronectin synthesis through blockade of Nox4-dependent ROS and peroxynitrite generation, with subsequent eNOS uncoupling. We also find that HG negatively regulates sestrin 2 and AMPK, thereby promoting Nox4-mediated eNOS dysfunction and increased fibronectin. These data identify a protective function for sestrin 2/AMPK and potential targets for intervention to prevent fibrotic injury in diabetes.
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94
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Sid B, Verrax J, Calderon PB. Role of AMPK activation in oxidative cell damage: Implications for alcohol-induced liver disease. Biochem Pharmacol 2013; 86:200-9. [PMID: 23688501 DOI: 10.1016/j.bcp.2013.05.007] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 05/03/2013] [Accepted: 05/08/2013] [Indexed: 02/08/2023]
Abstract
Chronic alcohol consumption is a well-known risk factor for liver disease. Progression of alcohol-induced liver disease (ALD) is a multifactorial process that involves a number of genetic, nutritional and environmental factors. Experimental and clinical studies increasingly show that oxidative damage induced by ethanol contributes in many ways to the pathogenesis of alcohol hepatoxicity. Oxidative stress appears to activate AMP-activated protein kinase (AMPK) signaling system, which has emerged in recent years as a kinase that controls the redox-state and mitochondrial function. This review focuses on the most recent insights concerning the activation of AMPK by reactive oxygen species (ROS), and describes recent evidences supporting the hypothesis that AMPK signaling pathways play an important role in promoting cell viability under conditions of oxidative stress, such as during alcohol exposure. We suggest that AMPK activation by ROS can promote cell survival by inducing autophagy, mitochondrial biogenesis and expression of genes involved in antioxidant defense. Hence, increased intracellular concentrations of ROS may represent a general mechanism for enhancement of AMPK-mediated cellular adaptation, including maintenance of redox homeostasis. On the other hand, AMPK inhibition in the liver by ethanol appears to play a key role in the development of steatosis induced by chronic alcohol consumption. Although more studies are needed to assess the functions of AMPK during oxidative stress, AMPK may be a possible therapeutic target in the particular case of alcohol-induced liver disease.
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Affiliation(s)
- Brice Sid
- Université Catholique de Louvain, Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group GTOX, Brussels, Belgium
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95
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Isoproterenol instigates cardiomyocyte apoptosis and heart failure via AMPK inactivation-mediated endoplasmic reticulum stress. Apoptosis 2013; 18:800-10. [DOI: 10.1007/s10495-013-0843-5] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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96
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Morales-Alamo D, Ponce-González JG, Guadalupe-Grau A, Rodríguez-García L, Santana A, Cusso R, Guerrero M, Dorado C, Guerra B, Calbet JAL. Critical role for free radicals on sprint exercise-induced CaMKII and AMPKα phosphorylation in human skeletal muscle. J Appl Physiol (1985) 2013; 114:566-77. [PMID: 23288553 DOI: 10.1152/japplphysiol.01246.2012] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The extremely high energy demand elicited by sprint exercise is satisfied by an increase in O2 consumption combined with a high glycolytic rate, leading to a marked lactate accumulation, increased AMP-to-ATP ratio, and reduced NAD(+)/NADH.H(+) and muscle pH, which are accompanied by marked Thr(172) AMP-activated protein kinase (AMPK)-α phosphorylation during the recovery period by a mechanism not fully understood. To determine the role played by reactive nitrogen and oxygen species (RNOS) on Thr(172)-AMPKα phosphorylation in response to cycling sprint exercise, nine voluntary participants performed a single 30-s sprint (Wingate test) on two occasions: one 2 h after the ingestion of placebo and another after the intake of antioxidants (α-lipoic acid, vitamin C, and vitamin E) in a double-blind design. Vastus lateralis muscle biopsies were obtained before, immediately postsprint, and 30 and 120 min postsprint. Performance and muscle metabolism were similar during both sprints. The NAD(+)-to-NADH.H(+) ratio was similarly reduced (84%) and the AMP-to-ATP ratio was similarly increased (×21-fold) immediately after the sprints. Thr(286) Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and Thr(172)-AMPKα phosphorylations were increased after the control sprint (with placebo) but not when the sprints were preceded by the ingestion of antioxidants. Ser(485)-AMPKα1/Ser(491)-AMPKα2 phosphorylation, a known inhibitory mechanism of Thr(172)-AMPKα phosphorylation, was increased only with antioxidant ingestion. In conclusion, RNOS play a crucial role in AMPK-mediated signaling after sprint exercise in human skeletal muscle. Antioxidant ingestion 2 h before sprint exercise abrogates the Thr(172)-AMPKα phosphorylation response observed after the ingestion of placebo by reducing CaMKII and increasing Ser(485)-AMPKα1/Ser(491)-AMPKα2 phosphorylation. Sprint performance, muscle metabolism, and AMP-to-ATP and NAD(+)-to-NADH.H(+) ratios are not affected by the acute ingestion of antioxidants.
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Affiliation(s)
- David Morales-Alamo
- Department of Physical Education, University of Las Palmas de Gran Canaria, Campus Universitario de Tafira, Las Palmas de Gran Canaria 35017, Canary Island, Spain
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97
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de Lima FM, Albertini R, Dantas Y, Maia-Filho AL, Santana CDL, Castro-Faria-Neto HC, França C, Villaverde AB, Aimbire F. Low-level laser therapy restores the oxidative stress balance in acute lung injury induced by gut ischemia and reperfusion. Photochem Photobiol 2012; 89:179-88. [PMID: 22882462 DOI: 10.1111/j.1751-1097.2012.01214.x] [Citation(s) in RCA: 295] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 07/13/2012] [Indexed: 11/30/2022]
Abstract
It remains unknown if the oxidative stress can be regulated by low-level laser therapy (LLLT) in lung inflammation induced by intestinal reperfusion (i-I/R). A study was developed in which rats were irradiated (660 nm, 30 mW, 5.4 J) on the skin over the bronchus and euthanized 2 h after the initial of intestinal reperfusion. Lung edema and bronchoalveolar lavage fluid neutrophils were measured by the Evans blue extravasation and myeloperoxidase (MPO) activity respectively. Lung histology was used for analyzing the injury score. Reactive oxygen species (ROS) was measured by fluorescence. Both expression intercellular adhesion molecule 1 (ICAM-1) and peroxisome proliferator-activated receptor-y (PPARy) were measured by RT-PCR. The lung immunohistochemical localization of ICAM-1 was visualized as a brown stain. Both lung HSP70 and glutathione protein were evaluated by ELISA. LLLT reduced neatly the edema, neutrophils influx, MPO activity and ICAM-1 mRNA expression. LLLT also reduced the ROS formation and oppositely increased GSH concentration in lung from i-I/R groups. Both HSP70 and PPARy expression also were elevated after laser irradiation. Results indicate that laser effect in attenuating the acute lung inflammation is driven to restore the balance between the pro- and antioxidants mediators rising of PPARy expression and consequently the HSP70 production.
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Affiliation(s)
- Flávia Mafra de Lima
- Department of Rehabilitation Sciences, Universidade Nove de Julho-UNINOVE, São Paulo, SP, Brazil
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98
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Park CS, Bang BR, Kwon HS, Moon KA, Kim TB, Lee KY, Moon HB, Cho YS. Metformin reduces airway inflammation and remodeling via activation of AMP-activated protein kinase. Biochem Pharmacol 2012; 84:1660-70. [PMID: 23041647 DOI: 10.1016/j.bcp.2012.09.025] [Citation(s) in RCA: 151] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 09/26/2012] [Accepted: 09/26/2012] [Indexed: 12/19/2022]
Abstract
Recent reports have suggested that metformin has anti-inflammatory and anti-tissue remodeling properties. We investigated the potential effect of metformin on airway inflammation and remodeling in asthma. The effect of metformin treatment on airway inflammation and pivotal characteristics of airway remodeling were examined in a murine model of chronic asthma generated by repetitive challenges with ovalbumin and fungal-associated allergenic protease. To investigate the underlying mechanism of metformin, oxidative stress levels and AMP-activated protein kinase (AMPK) activation were assessed. To further elucidate the role of AMPK, we examined the effect of 5-aminoimidazole-4-carboxamide-1-β-4-ribofuranoside (AICAR) as a specific activator of AMPK and employed AMPKα1-deficient mice as an asthma model. The role of metformin and AMPK in tissue fibrosis was evaluated using a bleomycin-induced acute lung injury model and in vitro experiments with cultured fibroblasts. Metformin suppressed eosinophilic inflammation and significantly reduced peribronchial fibrosis, smooth muscle layer thickness, and mucin secretion. Enhanced AMPK activation and decreased oxidative stress in lungs was found in metformin-treated asthmatic mice. Similar results were observed in the AICAR-treated group. In addition, the enhanced airway inflammation and fibrosis in heterozygous AMPKα1-deficient mice were induced by both allergen and bleomycin challenges. Fibronectin and collagen expression was diminished by metformin through AMPKα1 activation in cultured fibroblasts. Therefore metformin reduced both airway inflammation and remodeling at least partially through the induction of AMPK activation and decreased oxidative stress. These data provide insight into the beneficial role of metformin as a novel therapeutic drug for chronic asthma.
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Affiliation(s)
- Chan Sun Park
- Department of Internal Medicine, Haeundae Paik Hospital, Inje University, Busan, Republic of Korea
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99
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Morales-Alamo D, Ponce-González JG, Guadalupe-Grau A, Rodríguez-García L, Santana A, Cusso MR, Guerrero M, Guerra B, Dorado C, Calbet JAL. Increased oxidative stress and anaerobic energy release, but blunted Thr172-AMPKα phosphorylation, in response to sprint exercise in severe acute hypoxia in humans. J Appl Physiol (1985) 2012; 113:917-28. [PMID: 22858621 DOI: 10.1152/japplphysiol.00415.2012] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
AMP-activated protein kinase (AMPK) is a major mediator of the exercise response and a molecular target to improve insulin sensitivity. To determine if the anaerobic component of the exercise response, which is exaggerated when sprint is performed in severe acute hypoxia, influences sprint exercise-elicited Thr(172)-AMPKα phosphorylation, 10 volunteers performed a single 30-s sprint (Wingate test) in normoxia and in severe acute hypoxia (inspired Po(2): 75 mmHg). Vastus lateralis muscle biopsies were obtained before and immediately after 30 and 120 min postsprint. Mean power output and O(2) consumption were 6% and 37%, respectively, lower in hypoxia than in normoxia. O(2) deficit and muscle lactate accumulation were greater in hypoxia than in normoxia. Carbonylated skeletal muscle and plasma proteins were increased after the sprint in hypoxia. Thr(172)-AMPKα phosphorylation was increased by 3.1-fold 30 min after the sprint in normoxia. This effect was prevented by hypoxia. The NAD(+)-to-NADH.H(+) ratio was reduced (by 24-fold) after the sprints, with a greater reduction in hypoxia than in normoxia (P < 0.05), concomitant with 53% lower sirtuin 1 (SIRT1) protein levels after the sprint in hypoxia (P < 0.05). This could have led to lower liver kinase B1 (LKB1) activation by SIRT1 and, hence, blunted Thr(172)-AMPKα phosphorylation. Ser(485)-AMPKα(1)/Ser(491)-AMPKα(2) phosphorylation, a known negative regulating mechanism of Thr(172)-AMPKα phosphorylation, was increased by 60% immediately after the sprint in hypoxia, coincident with increased Thr(308)-Akt phosphorylation. Collectively, our results indicate that the signaling response to sprint exercise in human skeletal muscle is altered in severe acute hypoxia, which abrogated Thr(172)-AMPKα phosphorylation, likely due to lower LKB1 activation by SIRT1.
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Affiliation(s)
- David Morales-Alamo
- Department of Physical Education, University of Las Palmas de Gran Canaria (Campus Universitario de Tafira Las Palmas de Gran Canaria, Spain
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