1
|
Jing Cao, Zhang G, Liu Z, Xu Q, Li C, Cheng G, Shi R. Peroxidasin promotes diabetic vascular endothelial dysfunction induced by advanced glycation end products via NOX2/HOCl/Akt/eNOS pathway. Redox Biol 2021; 45:102031. [PMID: 34116361 PMCID: PMC8192873 DOI: 10.1016/j.redox.2021.102031] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 05/14/2021] [Accepted: 05/31/2021] [Indexed: 11/11/2022] Open
Abstract
Reactive oxygen species (ROS) derived from NADPH oxidases (NOX) plays an essential role in advanced glycation end products (AGEs)-induced diabetic vascular endothelial dysfunction. Peroxidasin (PXDN, VPO1) is one member of peroxidases family that catalyzes hydrogen peroxide (H2O2) to hypochlorous acid (HOCl). This present study aimed to elucidate the role of PXDN in promoting vascular endothelial dysfunction induced by AGEs in diabetes mellitus. We found that, compared to non-diabetic (db/m) mice, PXDN expression was notably increased in db/db mice with impaired endothelium-dependent relaxation. Knockdown of PXDN in vivo through tail vein injection of siRNA restored the impaired endothelium-dependent relaxation function of db/db mice which is accompanied with up-regulation of eNOS Ser1177 phosphorylation and NO production. AGEs significantly elevated expression of PXDN and 3-Cl-Tyr, but decreased phosphorylation of Akt and eNOS and NO release in HUVECs. All these effects induced by AGEs were remarkable alleviated by silencing PXDN with small interfering RNAs. In addition, HOCl treatment alone as well as HOCl added with Akt inhibitor MK2206 inhibited phosphorylation of Akt and eNOS, reducing NO production. More importantly,AGEs-induced up-regulation of PXDN and 3-Cl-Tyr with endothelial dysfunction were transformed by NOX2 silencing and H2O2 scavengers. Thus, these results support the conclusion that PXDN promotes AGEs-induced diabetic vascular endothelial dysfunction by attenuating eNOS phosphorylation at Ser1177 via NOX2/HOCl/Akt pathway.
Collapse
Affiliation(s)
- Jing Cao
- Department of Cardiovascular Medicine, The Third Xiangya Hospital of Central South University, 410013, Changsha, China.
| | - Guogang Zhang
- Department of Cardiovascular Medicine, The Third Xiangya Hospital of Central South University, 410013, Changsha, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.
| | - Zhaoya Liu
- Department of Geriatrics, The Third Xiangya Hospital of Central South University, 410013, Changsha, China.
| | - Qian Xu
- Department of Cardiothoracic Surgery, Xiangya Hospital, Central South University, 410008, Changsha, China.
| | - Chan Li
- Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, 41008, Changsha, China.
| | - Guangjie Cheng
- Division of Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, 35294, AL, USA.
| | - Ruizheng Shi
- Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, 41008, Changsha, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.
| |
Collapse
|
2
|
Deng L, Du C, Song P, Chen T, Rui S, Armstrong DG, Deng W. The Role of Oxidative Stress and Antioxidants in Diabetic Wound Healing. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:8852759. [PMID: 33628388 PMCID: PMC7884160 DOI: 10.1155/2021/8852759] [Citation(s) in RCA: 175] [Impact Index Per Article: 58.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 12/29/2020] [Indexed: 12/16/2022]
Abstract
Foot ulcers are one of the most common and severe complication of diabetes mellitus with significant resultant morbidity and mortality. Multiple factors impair wound healing include skin injury, diabetic neuropathy, ischemia, infection, inadequate glycemic control, poor nutritional status, and severe morbidity. It is currently believed that oxidative stress plays a vital role in diabetic wound healing. An imbalance of free radicals and antioxidants in the body results in overproduction of reactive oxygen species which lead to cell, tissue damage, and delayed wound healing. Therefore, decreasing ROS levels through antioxidative systems may reduce oxidative stress-induced damage to improve healing. In this context, we provide an update on the role of oxidative stress and antioxidants in diabetic wound healing through following four perspectives. We then discuss several therapeutic strategies especially dietary bioactive compounds by targeting oxidative stress to improve wounds healing.
Collapse
Affiliation(s)
- Liling Deng
- Department of Endocrinology, Multidisciplinary Diabetic Foot Medical Center, Chongqing Emergency Medical Center, Chongqing University Central Hospital, Chongqing 400014, China
| | - Chenzhen Du
- Department of Endocrinology, Multidisciplinary Diabetic Foot Medical Center, Chongqing Emergency Medical Center, Chongqing University Central Hospital, Chongqing 400014, China
| | - Peiyang Song
- Department of Endocrinology, Multidisciplinary Diabetic Foot Medical Center, Chongqing Emergency Medical Center, Chongqing University Central Hospital, Chongqing 400014, China
| | - Tianyi Chen
- Department of Endocrinology, Multidisciplinary Diabetic Foot Medical Center, Chongqing Emergency Medical Center, Chongqing University Central Hospital, Chongqing 400014, China
| | - Shunli Rui
- Department of Endocrinology, Multidisciplinary Diabetic Foot Medical Center, Chongqing Emergency Medical Center, Chongqing University Central Hospital, Chongqing 400014, China
| | - David G. Armstrong
- Department of Surgery, Keck School of Medicine of the University of Southern California, CA, USA
| | - Wuquan Deng
- Department of Endocrinology, Multidisciplinary Diabetic Foot Medical Center, Chongqing Emergency Medical Center, Chongqing University Central Hospital, Chongqing 400014, China
| |
Collapse
|
3
|
Boudreau A, Richard AJ, Harvey I, Stephens JM. Artemisia scoparia and Metabolic Health: Untapped Potential of an Ancient Remedy for Modern Use. Front Endocrinol (Lausanne) 2021; 12:727061. [PMID: 35211087 PMCID: PMC8861327 DOI: 10.3389/fendo.2021.727061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 12/16/2021] [Indexed: 11/19/2022] Open
Abstract
Botanicals have a long history of medicinal use for a multitude of ailments, and many modern pharmaceuticals were originally isolated from plants or derived from phytochemicals. Among these, artemisinin, first isolated from Artemisia annua, is the foundation for standard anti-malarial therapies. Plants of the genus Artemisia are among the most common herbal remedies across Asia and Central Europe. The species Artemisia scoparia (SCOPA) is widely used in traditional folk medicine for various liver diseases and inflammatory conditions, as well as for infections, fever, pain, cancer, and diabetes. Modern in vivo and in vitro studies have now investigated SCOPA's effects on these pathologies and its ability to mitigate hepatotoxicity, oxidative stress, obesity, diabetes, and other disease states. This review focuses on the effects of SCOPA that are particularly relevant to metabolic health. Indeed, in recent years, an ethanolic extract of SCOPA has been shown to enhance differentiation of cultured adipocytes and to share some properties of thiazolidinediones (TZDs), a class of insulin-sensitizing agonists of the adipogenic transcription factor PPARγ. In a mouse model of diet-induced obesity, SCOPA diet supplementation lowered fasting insulin and glucose levels, while inducing metabolically favorable changes in adipose tissue and liver. These observations are consistent with many lines of evidence from various tissues and cell types known to contribute to metabolic homeostasis, including immune cells, hepatocytes, and pancreatic beta-cells. Compounds belonging to several classes of phytochemicals have been implicated in these effects, and we provide an overview of these bioactives. The ongoing global epidemics of obesity and metabolic disease clearly require novel therapeutic approaches. While the mechanisms involved in SCOPA's effects on metabolic, anti-inflammatory, and oxidative stress pathways are not fully characterized, current data support further investigation of this plant and its bioactives as potential therapeutic agents in obesity-related metabolic dysfunction and many other conditions.
Collapse
Affiliation(s)
- Anik Boudreau
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Allison J. Richard
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Innocence Harvey
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Jacqueline M. Stephens
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, United States
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, United States
- *Correspondence: Jacqueline M. Stephens,
| |
Collapse
|
4
|
Nasoohi S, Parveen K, Ishrat T. Metabolic Syndrome, Brain Insulin Resistance, and Alzheimer's Disease: Thioredoxin Interacting Protein (TXNIP) and Inflammasome as Core Amplifiers. J Alzheimers Dis 2019; 66:857-885. [PMID: 30372683 DOI: 10.3233/jad-180735] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Empirical evidence indicates a strong association between insulin resistance and pathological alterations related to Alzheimer's disease (AD) in different cerebral regions. While cerebral insulin resistance is not essentially parallel with systemic metabolic derangements, type 2 diabetes mellitus (T2DM) has been established as a risk factor for AD. The circulating "toxic metabolites" emerging in metabolic syndrome may engage several biochemical pathways to promote oxidative stress and neuroinflammation leading to impair insulin function in the brain or "type 3 diabetes". Thioredoxin-interacting protein (TXNIP) as an intracellular amplifier of oxidative stress and inflammasome activation may presumably mediate central insulin resistance. Emerging data including those from our recent studies has demonstrated a sharp TXNIP upregulation in stroke, aging and AD and well underlining the significance of this hypothesis. With the main interest to illustrate TXNIP place in type 3 diabetes, the present review primarily briefs the potential mechanisms contributing to cerebral insulin resistance in a metabolically deranged environment. Then with a particular focus on plausible TXNIP functions to drive and associate with AD pathology, we present the most recent evidence supporting TXNIP as a promising therapeutic target in AD as an age-associated dementia.
Collapse
|
5
|
Lee JH, Park A, Oh KJ, Lee SC, Kim WK, Bae KH. The Role of Adipose Tissue Mitochondria: Regulation of Mitochondrial Function for the Treatment of Metabolic Diseases. Int J Mol Sci 2019; 20:ijms20194924. [PMID: 31590292 PMCID: PMC6801758 DOI: 10.3390/ijms20194924] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 09/29/2019] [Accepted: 09/30/2019] [Indexed: 02/07/2023] Open
Abstract
: Mitochondria play a key role in maintaining energy homeostasis in metabolic tissues, including adipose tissues. The two main types of adipose tissues are the white adipose tissue (WAT) and the brown adipose tissue (BAT). WAT primarily stores excess energy, whereas BAT is predominantly responsible for energy expenditure by non-shivering thermogenesis through the mitochondria. WAT in response to appropriate stimuli such as cold exposure and β-adrenergic agonist undergoes browning wherein it acts as BAT, which is characterized by the presence of a higher number of mitochondria. Mitochondrial dysfunction in adipocytes has been reported to have strong correlation with metabolic diseases, including obesity and type 2 diabetes. Dysfunction of mitochondria results in detrimental effects on adipocyte differentiation, lipid metabolism, insulin sensitivity, oxidative capacity, and thermogenesis, which consequently lead to metabolic diseases. Recent studies have shown that mitochondrial function can be improved by using thiazolidinedione, mitochondria-targeted antioxidants, and dietary natural compounds; by performing exercise; and by controlling caloric restriction, thereby maintaining the metabolic homeostasis by inducing adaptive thermogenesis of BAT and browning of WAT. In this review, we focus on and summarize the molecular regulation involved in the improvement of mitochondrial function in adipose tissues so that strategies can be developed to treat metabolic diseases.
Collapse
Affiliation(s)
- Jae Ho Lee
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea
| | - Anna Park
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea
| | - Kyoung-Jin Oh
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34141, Korea
| | - Sang Chul Lee
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34141, Korea
| | - Won Kon Kim
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea.
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34141, Korea.
| | - Kwang-Hee Bae
- Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Korea.
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon 34141, Korea.
| |
Collapse
|
6
|
Shawky NM, Shehatou GSG, Suddek GM, Gameil NM. Comparison of the effects of sulforaphane and pioglitazone on insulin resistance and associated dyslipidemia, hepatosteatosis, and endothelial dysfunction in fructose-fed rats. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2019; 66:43-54. [PMID: 30597379 DOI: 10.1016/j.etap.2018.12.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 12/07/2018] [Accepted: 12/13/2018] [Indexed: 06/09/2023]
Abstract
The purpose of this work was to compare the influences of sulforaphane (SFN) to those of the standard insulin sensitizer pioglitazone (PIO) on high fructose diet (HFrD)-induced insulin resistance, dyslipidemia, hepatosteatosis, and vascular dysfunction in rats. Male Sprague Dawley rats (150-200 g) were fed on a standard diet (control) or a high fructose diet (HFrD, 60% w/w fructose) for 60 days. From day 16, two subgroups of HFrD-fed rats received either SFN (0.5 mg/kg/day, orally) or PIO (5 mg/kg/day, orally) along with HFrD until the end of the experiment. Fructose-fed rats showed significant decreases in food intake, body weight and feeding efficiency; effects that were not altered by either treatment. Data from insulin tolerance test (ITT), oral glucose tolerance test (OGTT), and HOMA-IR and HOMA-β indices demonstrated impaired insulin sensitivity and glucose utilization in HFrD-fed rats. SFN and PIO treatments significantly reduced OGTTAUC (Glass's Delta values = 1.12 and 0.84, respectively), decreased ITTAUC (Glass's Delta values = 1.05 and 0.71, respectively), significantly diminished HOMA-IR index (by 55.6% and 77.6%, respectively), and increased HOMA-β value (by 1.8 and 1.3 fold, respectively) compared to the HFrD rats. Moreover, SFN and PIO ameliorated hepatic oxidative stress and reduced serum levels of C-reactive protein and lactate dehydrogenase in HFrD-fed rats. Furthermore, SFN and PIO administrations improved insulin resistance-associated heaptosteatosis and enhanced vascular responsiveness to acetylcholine-induced relaxations. However, only SFN was able to enhance serum HDL-C levels in HFrD group. These finding suggests that SFN elicited insulin-sensitizing, hepatoprotective, and vasculoprotective effects in HFrD insulin-resistant rats that were comparable to those exerted by PIO.
Collapse
Affiliation(s)
- Noha M Shawky
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt.
| | - George S G Shehatou
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| | - Ghada M Suddek
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| | - Nariman M Gameil
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| |
Collapse
|
7
|
Griffith CM, Eid T, Rose GM, Patrylo PR. Evidence for altered insulin receptor signaling in Alzheimer's disease. Neuropharmacology 2018; 136:202-215. [PMID: 29353052 DOI: 10.1016/j.neuropharm.2018.01.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 12/19/2017] [Accepted: 01/05/2018] [Indexed: 12/11/2022]
Abstract
Epidemiological data have shown that metabolic disease can increase the propensity for developing cognitive decline and dementia, particularly Alzheimer's disease (AD). While this interaction is not completely understood, clinical studies suggest that both hyper- and hypoinsulinemia are associated with an increased risk for developing AD. Indeed, insulin signaling is altered in post-mortem brain tissue from AD patients and treatments known to enhance insulin signaling can improve cognitive function. Further, clinical evidence has shown that AD patients and mouse models of AD often display alterations in peripheral metabolism. Since insulin is primarily derived from the periphery, it is likely that changes in peripheral insulin levels lead to alterations in central nervous system (CNS) insulin signaling and could contribute to cognitive decline and pathogenesis. Developing a better understanding of the relationship between alterations in peripheral metabolism and cognitive function might provide a foundation for the development of better treatment options for patients with AD. In this article we will begin to piece together the present data defining this relationship by briefly discussing insulin signaling in the periphery and CNS, its role in cognitive function, insulin's relationship to AD, peripheral metabolic alterations in mouse models of AD and how information from these models helps understand the mechanisms through which these changes potentially lead to impairments in insulin signaling in the CNS, and potential ways to target insulin signaling that could improve cognitive function in AD. This article is part of the Special Issue entitled 'Metabolic Impairment as Risk Factors for Neurodegenerative Disorders.'
Collapse
Affiliation(s)
- Chelsea M Griffith
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA; Center for Integrated Research in Cognitive and Neural Sciences, Southern Illinois University Carbondale, IL 62901, USA
| | - Tore Eid
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT 06510, USA; Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Gregory M Rose
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA; Department of Anatomy, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA; Center for Integrated Research in Cognitive and Neural Sciences, Southern Illinois University Carbondale, IL 62901, USA
| | - Peter R Patrylo
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA; Department of Anatomy, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA; Center for Integrated Research in Cognitive and Neural Sciences, Southern Illinois University Carbondale, IL 62901, USA.
| |
Collapse
|
8
|
Panigrahy SK, Bhatt R, Kumar A. Reactive oxygen species: sources, consequences and targeted therapy in type 2 diabetes. J Drug Target 2016; 25:93-101. [PMID: 27356044 DOI: 10.1080/1061186x.2016.1207650] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Oxidative stress has been considered as a central mediator in the progression of diabetic complication. The intracellular reactive oxygen species (ROS) leads to oxidative stress and it is raised from the mitochondria as well as by activation of five major pathways: increased polyol pathway flux, activation of protein kinase C (PKC) pathway, increased formation of advanced glycation end products (AGEs), over activity of hexosamine pathway and increased production of angiotensin II. The increased ROS through these pathways leads to β-cell dysfunction and insulin resistance, responsible for cell damage and death. This review not only highlights the sources of ROS production and their involvement in the progression of diabetes, but also emphasizes on pharmacological interventions and targeting of ROS in type 2 diabetes. This review summarizes the ROS as potential therapeutic targets, based on a putative mechanism in the progression of the diabetes. It also summarizes current knowledge of ROS activation in type 2 diabetes as well as ROS as a possible target for its treatment. Eventually, it would be a promising target for various strategies and drugs to modulate ROS levels in diabetes.
Collapse
Affiliation(s)
- Suchitra Kumari Panigrahy
- a Department of Biotechnology , Guru Ghasidas Vishwavidyalaya (a Central University) , Bilaspur , India
| | - Renu Bhatt
- a Department of Biotechnology , Guru Ghasidas Vishwavidyalaya (a Central University) , Bilaspur , India
| | - Awanish Kumar
- b Department of Biotechnology , National Institute of Technology (NIT) , Raipur , India
| |
Collapse
|
9
|
Wang X, Hai C. Novel insights into redox system and the mechanism of redox regulation. Mol Biol Rep 2016; 43:607-28. [DOI: 10.1007/s11033-016-4022-y] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 05/26/2016] [Indexed: 12/20/2022]
|
10
|
Hormetic and regulatory effects of lipid peroxidation mediators in pancreatic beta cells. Mol Aspects Med 2016; 49:49-77. [PMID: 27012748 DOI: 10.1016/j.mam.2016.03.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 02/23/2016] [Accepted: 03/09/2016] [Indexed: 12/12/2022]
Abstract
Nutrient sensing mechanisms of carbohydrates, amino acids and lipids operate distinct pathways that are essential for the adaptation to varying metabolic conditions. The role of nutrient-induced biosynthesis of hormones is paramount for attaining metabolic homeostasis in the organism. Nutrient overload attenuate key metabolic cellular functions and interfere with hormonal-regulated inter- and intra-organ communication, which may ultimately lead to metabolic derangements. Hyperglycemia and high levels of saturated free fatty acids induce excessive production of oxygen free radicals in tissues and cells. This phenomenon, which is accentuated in both type-1 and type-2 diabetic patients, has been associated with the development of impaired glucose tolerance and the etiology of peripheral complications. However, low levels of the same free radicals also induce hormetic responses that protect cells against deleterious effects of the same radicals. Of interest is the role of hydroxyl radicals in initiating peroxidation of polyunsaturated fatty acids (PUFA) and generation of α,β-unsaturated reactive 4-hydroxyalkenals that avidly form covalent adducts with nucleophilic moieties in proteins, phospholipids and nucleic acids. Numerous studies have linked the lipid peroxidation product 4-hydroxy-2E-nonenal (4-HNE) to different pathological and cytotoxic processes. Similarly, two other members of the family, 4-hydroxyl-2E-hexenal (4-HHE) and 4-hydroxy-2E,6Z-dodecadienal (4-HDDE), have also been identified as potential cytotoxic agents. It has been suggested that 4-HNE-induced modifications in macromolecules in cells may alter their cellular functions and modify signaling properties. Yet, it has also been acknowledged that these bioactive aldehydes also function as signaling molecules that directly modify cell functions in a hormetic fashion to enable cells adapt to various stressful stimuli. Recent studies have shown that 4-HNE and 4-HDDE, which activate peroxisome proliferator-activated receptor δ (PPARδ) in vascular endothelial cells and insulin secreting beta cells, promote such adaptive responses to ameliorate detrimental effects of high glucose and diabetes-like conditions. In addition, due to the electrophilic nature of these reactive aldehydes they form covalent adducts with electronegative moieties in proteins, phosphatidylethanolamine and nucleotides. Normally these non-enzymatic modifications are maintained below the cytotoxic range due to efficient cellular neutralization processes of 4-hydroxyalkenals. The major neutralizing enzymes include fatty aldehyde dehydrogenase (FALDH), aldose reductase (AR) and alcohol dehydrogenase (ADH), which transform the aldehyde to the corresponding carboxylic acid or alcohols, respectively, or by biding to the thiol group in glutathione (GSH) by the action of glutathione-S-transferase (GST). This review describes the hormetic and cytotoxic roles of oxygen free radicals and 4-hydroxyalkenals in beta cells exposed to nutritional challenges and the cellular mechanisms they employ to maintain their level at functional range below the cytotoxic threshold.
Collapse
|
11
|
Abstract
In the last few decades, rapid changes in lifestyle have led to an alarming increase in the prevalence of obesity and obesity-associated complications. Obese patients are at increased risk of developing hypertension, heart disease, insulin resistance, dyslipidemia, type 2 diabetes and kidney disease. The surplus of calories is normally stored as triglycerides in adipose tissue. However, excess lipids can also accumulate ectopically in other organs, including the kidney, contributing to their damage through toxic processes named lipotoxicity. The kidney is negatively affected by dyslipidemia, lipid accumulation and changes in circulating adipokines that bring about alterations in renal lipid metabolism and promote insulin resistance, generation of reactive oxygen species and endoplasmic reticulum stress, ultimately leading to alterations in the glomerular filtration barrier and renal failure. This review focuses on the pathogenic molecular mechanisms associated with renal lipotoxicity, and presents new insights about potential new therapeutic targets and biomarkers such as microRNAs and long non-coding RNAs, of relevance for the early detection of lipid-associated kidney disease.
Collapse
|
12
|
Kuzmenko D, Udintsev S, Klimentyeva T, Serebrov V. Oxidative stress in adipose tissue as a primary link in pathogenesis of insulin resistance. ACTA ACUST UNITED AC 2016; 62:14-21. [DOI: 10.18097/pbmc20166201014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Obesity is a leading risk factor of diabetes mellitus type 2, impairments of lipid metabolism and cardiovascular diseases. Dysfunctions of the accumulating weight of the visceral fat are primarily linked to pathogenesis of systemic insulin resistance. The review considers modern views about biochemical mechanisms underlying formation of oxidative stress in adipocytes at obesity, as one of key elements of impairments of their metabolism triggering formation of systemic insulin resistance.
Collapse
|
13
|
Yu X, Zhao X, Ze Y, Wang L, Liu D, Hong J, Xu B, Lin A, Zhang C, Zhao Y, Li B, Hong F. Changes of serum parameters of TiO₂ nanoparticle-induced atherosclerosis in mice. JOURNAL OF HAZARDOUS MATERIALS 2014; 280:364-71. [PMID: 25179109 DOI: 10.1016/j.jhazmat.2014.08.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Revised: 08/03/2014] [Accepted: 08/12/2014] [Indexed: 05/26/2023]
Abstract
The evaluation of toxicological effects of nanoparticulate matter is increasingly important due to their growing occupational use and presence as compounds in consumer products. Numerous studies have shown that exposure to nanosized particles lead to systemic inflammation in experimental animals, but whether long-term exposure to nanosized particles induces atherogenesis is rarely evaluated. In the current study, mice were continuously exposed to TiO2 nanoparticles (NPs) at 1.25, 2.5, or 5mg/kg body weight, administered by nasal instillation for nine consecutive months, and the association between serum parameter changes and atherosclerosis in mice were investigated. The present findings suggested that chronic exposure to TiO2 NPs resulted in atherogenesis coupling with pulmonary inflammation, increased levels of serum triglycerides, glucose, total cholesterol, low-density lipoprotein cholesterol, advanced glycation end products, reactive oxygen species, NAD(P)H oxidases 4, C-reaction protein, E-selectin, endothelin-1, tissue factor, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, monocyte chemoattractant protein-1, plasminogen activator inhibitor-1, and reduced levels of serum high-density lipoprotein cholesterol, nitric oxide and tissue plasminogen activator. Our study suggests an association of long-term exposure to TiO2 NPs with atherosclerosis and pulmonary inflammation. This finding demonstrates the hypothesized role of TiO2 NPs as a risk factor for atherogenesis.
Collapse
Affiliation(s)
- Xiaohong Yu
- Medical College of Soochow University, Suzhou 215123, China
| | - Xiaoyang Zhao
- Medical College of Soochow University, Suzhou 215123, China
| | - Yuguan Ze
- Medical College of Soochow University, Suzhou 215123, China
| | - Ling Wang
- Library of Soochow University, Suzhou 215123, China
| | - Dong Liu
- Medical College of Soochow University, Suzhou 215123, China
| | - Jie Hong
- Medical College of Soochow University, Suzhou 215123, China
| | - Bingqing Xu
- Medical College of Soochow University, Suzhou 215123, China
| | - Anan Lin
- Medical College of Soochow University, Suzhou 215123, China
| | - Chi Zhang
- Medical College of Soochow University, Suzhou 215123, China
| | - Yue Zhao
- Medical College of Soochow University, Suzhou 215123, China
| | - Bingyan Li
- Medical College of Soochow University, Suzhou 215123, China.
| | - Fashui Hong
- Medical College of Soochow University, Suzhou 215123, China.
| |
Collapse
|
14
|
Wang X, Wu H, Chen H, Liu R, Liu J, Zhang T, Yu W, Hai C. Does insulin bolster antioxidant defenses via the extracellular signal-regulated kinases-protein kinase B-nuclear factor erythroid 2 p45-related factor 2 pathway? Antioxid Redox Signal 2012; 16:1061-70. [PMID: 22149292 DOI: 10.1089/ars.2011.4460] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Oxidative stress plays a fundamental role in the development of diabetes, which has become a great threaten for health in the whole world. In recent years, it has been found that, in addition to the effect on metabolism, insulin plays an antioxidant role. However, the effect of insulin on the whole antioxidant enzyme system, especially in vivo, is not completely understood. We note that, in vitro and in vivo, insulin administration could sequentially and transiently increase a battery of antioxidant enzymes through the activation of the key transcription factor nuclear factor erythroid 2 p45-related factor 2 (Nrf2). The sequential activation of extracellular signal-regulated kinases (ERK)-protein kinase B (Akt) pathway maybe required for insulin-induced enhancement of antioxidant defense regulated by Nrf2. Our observation leads to the hypothesis that insulin regulates the redox balance and insulin bolsters antioxidant defenses via the ERK-Akt-Nrf2 pathway.
Collapse
Affiliation(s)
- Xin Wang
- Department of Toxicology, School of Preventive Medicine, The Fourth Military Medical University, Xi'an, China
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Ros Pérez M, Medina-Gómez G. [Obesity, adipogenesis and insulin resistance]. ACTA ACUST UNITED AC 2011; 58:360-9. [PMID: 21778123 DOI: 10.1016/j.endonu.2011.05.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 04/12/2011] [Accepted: 05/11/2011] [Indexed: 12/25/2022]
Abstract
Insulin resistance precedes the development of type 2 diabetes mellitus and is also a common denominator in the so-called metabolic syndrome. Although the cause of insulin resistance has not been fully elucidated, it seems clear that lifestyle changes, including little physical exercise and constant access to food, particularly in developed and economically emergent countries, as well as genetic factors, appear to have triggered the escalating incidence of diseases related to insulin resistance, including type 2 diabetes and metabolic syndrome. Obesity is considered as a risk factor for developing insulin resistance. Increased adipose tissue has been related to an increased production of pro-inflammatory cytokines which, together with fatty acids, appear to be responsible for the development of insulin resistance. Thus, a greater or lesser expansibility or ability of adipose tissue to store lipids also appears to play a significant role in the development of insulin resistance because overcoming of this capacity, which is variable in each case, would result in leaking of lipids to other tissues where they could interfere with insulin signaling. This article reviews various molecular mechanisms related to the development of insulin resistance and its relationship to expansibility of adipose tissue and obesity.
Collapse
Affiliation(s)
- Manuel Ros Pérez
- Departamento de Bioquímica, Fisiología y Genética Molecular, Universidad Rey Juan Carlos, Facultad de Ciencias de la Salud, Alcorcón, Madrid, España
| | | |
Collapse
|
16
|
Rains JL, Jain SK. Oxidative stress, insulin signaling, and diabetes. Free Radic Biol Med 2011; 50:567-75. [PMID: 21163346 PMCID: PMC3557825 DOI: 10.1016/j.freeradbiomed.2010.12.006] [Citation(s) in RCA: 892] [Impact Index Per Article: 68.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 11/29/2010] [Accepted: 12/04/2010] [Indexed: 12/14/2022]
Abstract
Oxidative stress has been implicated as a contributor to both the onset and the progression of diabetes and its associated complications. Some of the consequences of an oxidative environment are the development of insulin resistance, β-cell dysfunction, impaired glucose tolerance, and mitochondrial dysfunction, which can lead ultimately to the diabetic disease state. Experimental and clinical data suggest an inverse association between insulin sensitivity and ROS levels. Oxidative stress can arise from a number of different sources, whether disease state or lifestyle, including episodes of ketosis, sleep restriction, and excessive nutrient intake. Oxidative stress activates a series of stress pathways involving a family of serine/threonine kinases, which in turn have a negative effect on insulin signaling. More experimental evidence is needed to pinpoint the mechanisms contributing to insulin resistance in both type 1 diabetics and nondiabetic individuals. Oxidative stress can be reduced by controlling hyperglycemia and calorie intake. Overall, this review outlines various mechanisms that lead to the development of oxidative stress. Intervention and therapy that alter or disrupt these mechanisms may serve to reduce the risk of insulin resistance and the development of diabetes.
Collapse
Affiliation(s)
- Justin L Rains
- Department of Pediatrics, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA
| | | |
Collapse
|
17
|
Mlinar B, Marc J. New insights into adipose tissue dysfunction in insulin resistance. ACTA ACUST UNITED AC 2011; 49:1925-35. [DOI: 10.1515/cclm.2011.697] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Indexed: 12/14/2022]
Abstract
AbstractIn a state of caloric excess, adipose tissue plays an essential role by storing lipids. Its expandability determines the onset of metabolic syndrome (central obesity, dyslipidemia, glucose intolerance and hypertension). When the adipocyte endoplasmic reticulum is no longer capable of processing the excess nutrients, the so-called “endoplasmic reticulum stress” develops. This triggers efflux of free fatty acids from adipocytes into the circulation and causes triglyceride overload in skeletal muscle, liver and pancreas. Adipose tissue hypoxia then develops, due to the failure of vasculature to expand with adipocyte hypertrophy. Increased catabolism in mitochondria leads there to oxidative stress. Both phenomena cause deranged adipokine secretion and low-grade inflammation. Inflammatory cytokines, reactive oxygen species and ectopic lipid deposition are the main mediators of insulin resistance and vascular impairment, which both lead finally to diabetes type 2 and cardiovascular disease. Recently, fibrosis of adipose tissue was also demonstrated in obesity, contributing to the interplay of deleterious factors forcing inflammation. The present paper reviews recent evidence for adipose tissue dysfunction, trying to define causes and consequences. In conclusion, insulin resistance and associated complications originate from excess lipids, which cannot be stored without limit in adipose tissue, thus affecting its integrity and adipokine secretion.
Collapse
|
18
|
Schinzari F, Tesauro M, Rovella V, Galli A, Mores N, Porzio O, Lauro D, Cardillo C. Generalized impairment of vasodilator reactivity during hyperinsulinemia in patients with obesity-related metabolic syndrome. Am J Physiol Endocrinol Metab 2010; 299:E947-52. [PMID: 20923961 DOI: 10.1152/ajpendo.00426.2010] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Defective insulin-dependent vasodilation might contribute importantly to metabolic and vascular abnormalities of the metabolic syndrome (MetS). However, despite extensive investigation, the precise mechanisms involved in insulin's vasoactive effects have not been fully elucidated. Therefore, this study sought to better characterize insulin's physiological actions on vascular reactivity and their potential derangement in the MetS. Forearm blood flow responses to graded doses of acetylcholine, sodium nitroprusside, and verapamil were assessed by strain-gauge plethysmography in patients with obesity-related MetS (n = 20) and in matched controls (n = 18) before and after intra-arterial infusion of insulin (0.2 mU·kg(-1)·min(-1)). Possible involvement of increased oxidative stress in the impaired insulin-stimulated vasodilator responsiveness of patients with MetS (n = 12) was also investigated using vitamin C (25 mg/min). In control subjects, significant potentiation of the vasodilator responses to acetylcholine, nitroprusside, and verapamil was observed after insulin infusion (all P < 0.05). However, no significant change in vasodilator reactivity to either of these drugs was observed following hyperinsulinemia in patients with MetS (all P > 0.05). Interestingly, administration of vitamin C to patients with MetS during hyperinsulinemia significantly enhanced the vasodilator responsiveness to acetylcholine, nitroprusside, and verapamil (all P < 0.05 vs. hyperinsulinemia alone). In conclusion, insulin exerts a generalized facilitatory action on vasodilator reactivity, and this effect is impaired in patients with MetS likely because of increased oxidative stress. Given the importance of vasodilator reactivity in affecting glucose disposal and vascular homeostasis, this defect may then contribute to the development of metabolic and vascular complications in insulin-resistant states.
Collapse
|
19
|
Davidson EP, Coppey LJ, Calcutt NA, Oltman CL, Yorek MA. Diet-induced obesity in Sprague-Dawley rats causes microvascular and neural dysfunction. Diabetes Metab Res Rev 2010; 26:306-18. [PMID: 20503263 PMCID: PMC2878284 DOI: 10.1002/dmrr.1088] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The objective of this study was to determine the effect of diet-induced obesity (DIO) on microvascular and neural function. METHODS Rats were fed a standard or high fat diet for up to 32 weeks. The following measurements were carried out: vasodilation in epineurial arterioles using videomicroscopy, endoneurial blood flow using hydrogen clearance, nerve conduction velocity using electrical stimulation, size-frequency distribution of myelinated fibres of the sciatic nerve, intraepidermal nerve fibre density using confocal microscopy and thermal nociception using the Hargreaves method. RESULTS Rats fed a high fat diet for 32 weeks developed sensory neuropathy, as indicated by slowing of sensory nerve conduction velocity and thermal hypoalgesia. Motor nerve conduction velocity and endoneurial blood flow were not impaired. Mean axonal diameter of myelinated fibres of the sciatic nerve was unchanged in high fat-fed rats compared with that in control. Intraepidermal nerve fibre density was significantly reduced in high fat-fed rats. Vascular relaxation to acetylcholine and calcitonin gene-related peptide was decreased and expression of neutral endopeptidase (NEP) increased in epineurial arterioles of rats fed a high fat diet. In contrast, insulin-mediated vascular relaxation was increased in epineurial arterioles. NEP activity was significantly increased in the skin of the hindpaw. Markers of oxidative stress were increased in the aorta and serum of high fat-fed rats but not in epineurial arterioles. CONCLUSION Chronic obesity causes microvascular and neural dysfunction. This is associated with increased expression of NEP but not oxidative stress in epineurial arterioles. NEP degrades vasoactive peptides, which may explain the decrease in microvascular function.
Collapse
Affiliation(s)
- Eric P. Davidson
- Veteran Affairs Medical Center, University of Iowa, Iowa City, IA, 52246, USA
| | - Lawrence J. Coppey
- Veteran Affairs Medical Center, University of Iowa, Iowa City, IA, 52246, USA
| | - Nigel A. Calcutt
- Department of Pathology, University of California San Diego, CA, 92093, USA
| | - Christine L. Oltman
- Veteran Affairs Medical Center, University of Iowa, Iowa City, IA, 52246, USA
- Department of Internal Medicine, University of Iowa, Iowa City, IA, 52246, USA
| | - Mark A. Yorek
- Veteran Affairs Medical Center, University of Iowa, Iowa City, IA, 52246, USA
- Department of Internal Medicine, University of Iowa, Iowa City, IA, 52246, USA
| |
Collapse
|
20
|
Antioxidant Properties of an Endogenous Thiol: Alpha-lipoic Acid, Useful in the Prevention of Cardiovascular Diseases. J Cardiovasc Pharmacol 2009; 54:391-8. [DOI: 10.1097/fjc.0b013e3181be7554] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
21
|
Petrofsky J, Lohman E, Lee S, de la Cuesta Z, Labial L, Iouciulescu R, Moseley B, Korson R, Al Malty A. Effects of contrast baths on skin blood flow on the dorsal and plantar foot in people with type 2 diabetes and age-matched controls. Physiother Theory Pract 2009; 23:189-97. [PMID: 17687732 DOI: 10.1080/09593980701209295] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Contrast baths have been used for therapy for over 2,000 years. The basic concept is to alternate warm and cool water baths during a treatment session. It is believed that this will increase circulation better than just placing the limb in a warm water bath. However, there is little supportive evidence for this assertion. Further, for subjects with diabetes, with underlying impairments in their circulation, this may not work at all. Fourteen people with type 2 diabetes were compared to 14 age-matched controls. Skin blood flow of the foot (BF) was measured during 16 minutes of contrast baths at two different intervals: 3 minutes warm and 1 minute cold and 6 minutes warm and 2 minutes cold. In control subjects, warm and cold contrast baths with the ratio 3 minutes warm to 1 minute cold elicited significantly (p < 0.01) greater BF than placing the limb continuously in warm water or using a 6:2 ratio of warm to cold bath time. In control subjects, there was also a greater plantar than dorsal BF. For subjects with diabetes, there was no statistical difference between BF with contrast baths versus warm whirlpool; but in both cases BF was significantly less than that seen in control subjects under similar circumstances. There was also very little difference between BF on the plantar and dorsal aspects of the foot in the subjects with diabetes. Patients with diabetes do not show a vascular response to contrast bath therapy. The BF response to contrast temperatures may be a good diagnostic test for diabetic vascular impairment.
Collapse
Affiliation(s)
- Jerrold Petrofsky
- Department of Physical Therapy, Loma Linda University, Loma Linda, California 92350, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Disruption of the Nitric Oxide Signaling System in Diabetes. Cardiovasc Endocrinol 2008. [DOI: 10.1007/978-1-59745-141-3_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
|
23
|
Tesauro M, Schinzari F, Rovella V, Melina D, Mores N, Barini A, Mettimano M, Lauro D, Iantorno M, Quon MJ, Cardillo C. Tumor necrosis factor-alpha antagonism improves vasodilation during hyperinsulinemia in metabolic syndrome. Diabetes Care 2008; 31:1439-41. [PMID: 18390795 PMCID: PMC2453644 DOI: 10.2337/dc08-0219] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Obesity is associated with chronic inflammation due to overproduction of proinflammatory cytokines, including tumor necrosis factor (TNF)-alpha. We assessed the effects of TNF-alpha neutralization by infliximab on vascular reactivity during hyperinsulinemia in obesity-related metabolic syndrome. RESEARCH DESIGN AND METHODS Vascular responses to intra-arterial infusion of acetylcholine (ACh) and sodium nitroprusside (SNP) were assessed in patients with metabolic syndrome, before and after administration of infliximab. RESULTS Patients had blunted vasodilator responses to ACh and SNP during hyperinsulinemia compared with control subjects; a potentiation of the responsiveness to both ACh and SNP, however, was observed in patients following infliximab. The antioxidant vitamin C improved the vasodilator response to ACh in patients with metabolic syndrome, but its effect was not further enhanced by concurrent administration of infliximab. CONCLUSIONS TNF-alpha neutralization ameliorates vascular reactivity in metabolic syndrome during hyperinsulinemia, likely in relation to decreased oxidative stress, thereby suggesting an involvement of inflammatory cytokines in vascular dysfunction of these patients.
Collapse
|
24
|
Meyer M, Lieps D, Schatz H, Pfohl M. Impaired flow-mediated vasodilation in type 2 diabetes: Lack of relation to microvascular dysfunction. Microvasc Res 2008; 76:61-5. [DOI: 10.1016/j.mvr.2008.03.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 02/25/2008] [Accepted: 03/06/2008] [Indexed: 10/22/2022]
|
25
|
Kovacic P. Protein electron transfer (mechanism and reproductive toxicity): iminium, hydrogen bonding, homoconjugation, amino acid side chains (redox and charged), and cell signaling. ACTA ACUST UNITED AC 2007; 81:51-64. [PMID: 17539014 DOI: 10.1002/bdrc.20086] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This contribution presents novel biochemical perspectives of protein electron transfer (ET) with focus on the iminium nature of the peptide link, along with relationships to reproductive toxicity. The favorable influence of hydrogen bonding on protein ET has been widely documented. Hydrogen bonding of the zwitterionic peptide enhances iminium character. A wide array of such bonding agents is available in vivo, with many reports on the peptide link itself. ET proceeds along the backbone, due in part, to homoconjugation. Redox amino acids (AAs), mainly tyrosine (Tyr), tryptophan (Typ), histidine (His), cysteine (Cys), disulfide, and methionine (Met), are involved in the competing processes for radical formation: direct hydrogen atom abstraction versus electron and proton loss. It appears that the radical or radical cation generated during the redox process is capable of interacting with n-electrons of the backbone. Beneficial effects of cationic AAs impact the conduction process. A relationship apparently exists involving cell signaling, protein conduction, and radicals or electrons. In addition, the link between protein ET and reproductive toxicity is examined. A key element is the role of reactive oxygen species (ROS) generated by protein ET. There is extensive evidence for involvement of ROS in generation of birth defects. The radical species arise in protein mainly by ET transformations by enzymes, as illustrated in the case of alcoholism.
Collapse
Affiliation(s)
- Peter Kovacic
- Department of Chemistry, San Diego State University, San Diego, California 92065-1030, USA.
| |
Collapse
|
26
|
Abstract
Insulin resistance typically reflects multiple defects of insulin receptor and post-receptor signalling that impair a diverse range of metabolic and vascular actions. Many potential intervention targets and compounds with therapeutic activity have been described. Proof of principle for a non-peptide insulin mimetic has been demonstrated by specific activation of the intracellular B-subunit of the insulin receptor. Potentiation of insulin action has been achieved with agents that enhance phosphorylation and prolong the tyrosine kinase activity of the insulin receptor and its protein substrates after activation by insulin. These include inhibitors of phosphatases and serine kinases that normally prevent or terminate tyrosine kinase signalling. Additional approaches involve increasing the activity of phosphatidylinositol 3-kinase and other downstream components of the insulin signalling pathways. Experimental interventions to remove signalling defects caused by cytokines, certain adipocyte hormones, excess fatty acids, glucotoxicity and negative feedback by distal signalling steps have also indicated therapeutic possibilities. Several hormones, metabolic enzymes, minerals, co-factors and transcription co-activators have shown insulin-sensitising potential. Since insulin resistance affects many metabolic and cardiovascular diseases, it provides an opportunity for simultaneous therapeutic attack on a broad front.
Collapse
Affiliation(s)
- Clifford J Bailey
- Deabetes Research Group, School of Life and Health Sciences, Aston University, Birmingham, B4 7ET, UK.
| |
Collapse
|
27
|
Chen CF, Leu FJ, Chen HI, Wang D, Chou SJ. Lack of a Protective Effect of Insulin on Three Reperfusion-Liver Injury Models in Rats and Mice. Transplant Proc 2006; 38:2221-5. [PMID: 16980048 DOI: 10.1016/j.transproceed.2006.07.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
UNLABELLED Our objective was to investigate the potential protective effects of insulin on the liver injury induced in three ischemia and reperfusion (I/R) models. METHODS Three I/R models were used: (1) I/R of the liver was produced in isolated, perfused rat livers; (2) in in situ I/R of the liver in rats, ischemia was induced by clamping off the hepatic artery and portal vein for 40 minutes, the flow then restored, and the liver reperfused for 90 minutes; (3) in in situ I/R of the liver in mice, ischemia was induced by clamping off the hepatic artery for 15 minutes, the flow then restored, and the liver reperfused for 45 minutes. In all three cases, blood samples collected before ischemia and after reperfusion were analyzed for sGOT. Plasma nitrate/nitrite, hydroxyl radicals, and tumor necrosis factor were also measured. In each model, a dose of insulin sufficient to induce euglycemia was administered to assess its protective effect on liver injury and inflammation. RESULTS These I/R protocols resulted in a significant increase in sGOT and in three inflammatory parameters; nitric oxide, hydroxyl radicals, and tumor necrosis factor. Pretreatment with insulin did not attenuate the liver injury in any of the three I/R models. CONCLUSIONS Although insulin has been reported to provide anti-inflammatory benefits by reducing oxidative and nitrosative stress and cytokine release, none of these protective effects was seen in the three I/R-induced liver injury models we tested.
Collapse
Affiliation(s)
- C F Chen
- Division of Gastroenterology, Department of Internal Medicine, Cheng Hsin General Hospital, and School of Health, Ming Chuan University, Taipei, Taiwan
| | | | | | | | | |
Collapse
|
28
|
Abstract
Signal transduction via PI 3-kinases plays an important role in regulating the cellular processes of cell growth, survival, proliferation, and motility. The stimulated generation of reactive oxygen species is a necessary component of the signal transduction mechanisms by which many growth factors and cytokines activate this signaling pathway and elicit their cellular responses. Evidence now supports the oxidative inactivation of both tyrosine phosphatases acting upstream of PI 3-kinase, and of the lipid phosphatase PTEN as components of the normal stimulated regulation of PI 3-kinase signaling. However, the effects of chronic oxidative stress appear rather different, particularly a proposed role for nitrosylation of Akt and other targets leading to inhibition of PI 3-kinase signaling during diabetic insulin resistance in muscle. Recently, evidence has also begun to emerge, indicating that physiological redox signaling may display the same tight spatial and temporal specificity as seen with many other signal transduction systems in terms of targeting individual proteins for modification, and of enzymatic reversal mechanisms. This review will focus upon the details of these and other roles for reactive oxygen and nitrogen species in the regulation of PI 3-kinase signaling, both during acute stimulation and chronic oxidative stress, and the evidence for their significance.
Collapse
Affiliation(s)
- Nick R Leslie
- Division of Molecular Physiology, School of Life Sciences, University of Dundee, Wellcome Trust Biocentre, Dundee, United Kingdom.
| |
Collapse
|
29
|
Goldin A, Beckman JA, Schmidt AM, Creager MA. Advanced glycation end products: sparking the development of diabetic vascular injury. Circulation 2006; 114:597-605. [PMID: 16894049 DOI: 10.1161/circulationaha.106.621854] [Citation(s) in RCA: 1506] [Impact Index Per Article: 83.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Advanced glycation end products (AGEs) are proteins or lipids that become glycated after exposure to sugars. AGEs are prevalent in the diabetic vasculature and contribute to the development of atherosclerosis. The presence and accumulation of AGEs in many different cell types affect extracellular and intracellular structure and function. AGEs contribute to a variety of microvascular and macrovascular complications through the formation of cross-links between molecules in the basement membrane of the extracellular matrix and by engaging the receptor for advanced glycation end products (RAGE). Activation of RAGE by AGEs causes upregulation of the transcription factor nuclear factor-kappaB and its target genes. Soluble AGEs activate monocytes, and AGEs in the basement membrane inhibit monocyte migration. AGE-bound RAGE increases endothelial permeability to macromolecules. AGEs block nitric oxide activity in the endothelium and cause the production of reactive oxygen species. Because of the emerging evidence about the adverse effects of AGEs on the vasculature of patients with diabetes, a number of different therapies to inhibit AGEs are under investigation.
Collapse
Affiliation(s)
- Alison Goldin
- Cardiovascular Division, Brigham and Women's Hospital and Harvard Medical School, 75 Francis St, Boston, MA 02115, USA
| | | | | | | |
Collapse
|
30
|
Pan JW, Zheng X, Yang PY, Qin YW, Rui YC, Ma LP, Zhou F, Kang H. Different expressions of Nogo-B1 and Nogo-B2 in mouse heart microvascular endothelial cell dysfunction induced by lysophosphatidylcholine. Microvasc Res 2006; 72:42-7. [PMID: 16828122 DOI: 10.1016/j.mvr.2006.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2006] [Revised: 05/07/2006] [Accepted: 05/11/2006] [Indexed: 11/27/2022]
Abstract
To investigate Nogo-B expression changes in mouse heart microvascular endothelial H5V cell line induced by lysophosphatidylcholine. Cells were incubated with different concentrations of lysoPC for the same incubation time and with 10 micromol/l lysoPC at different incubation times. Protein and mRNA expression levels of Nogo-B1 and Nogo-B2 were measured with Western blotting and semiquantitative RT-PCR, respectively. Nogo-B1 protein was detected in normal H5V cells by Western blotting. When H5V cells were incubated with lysoPC, Nogo-B1 protein level decreased, and the lowest point fell to 20% of the original level induced by 20 micromol/l lysoPC for 24 h. Incubation of H5V cells with lysoPC of different concentrations or at different time points caused little change in Nogo-B1 mRNA expression level, except for a 50% decrease in 20 micromol/l lysoPC at 24 h, while a transient change was observed in Nogo-B2 mRNA level. These results demonstrate that Nogo-B1 protein expression could be down-regulated with increasing concentrations of lysoPC and lapse of incubation time, though no mRNA transcription down-regulation occurred. However, mRNA expression level of Nogo-B2 showed a transient up-regulation induced by lysoPC. We conclude that the two subtypes of Nogo-B may play different roles in the endothelial cell injury process.
Collapse
Affiliation(s)
- Jing-Wei Pan
- Department of Cardiology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Mukherjee S, Tessema M, Wandinger-Ness A. Vesicular Trafficking of Tyrosine Kinase Receptors and Associated Proteins in the Regulation of Signaling and Vascular Function. Circ Res 2006; 98:743-56. [PMID: 16574915 DOI: 10.1161/01.res.0000214545.99387.e3] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Receptor tyrosine kinases (RTKs) play a pivotal role in the development and function of the cardiovascular system. Ligand-activated RTKs promote numerous downstream signal transduction pathways that lead to vascular permeability, as well as proliferation, migration, and differentiation of vascular endothelia and smooth muscle cells. Ligand binding also promotes internalization of the activated receptors either to downregulate the signaling via degradation of the ligand/receptor complex or to signal from endosomes. However, the outcomes of receptor internalization via clathrin-dependent or caveolar pathways and trafficking mechanisms are incompletely clarified in vascular systems. Activity modulation through endocytosis and vesicular trafficking significantly impacts downstream targets of RTKs such as endothelial nitric oxide synthase (eNOS) and VE-cadherin. RTKs and their associated targets are also transported to the nucleus, where they may directly impact nuclear signaling. Although the nuclear transport pathways are just beginning to be unraveled, it appears that endocytosis and vesicular trafficking are involved. In this review, we discuss the mechanisms by which activated RTKs and the downstream targets eNOS and VE-cadherin may be internalized and transported to various intracellular compartments. How localization and interacting proteins impact protein function and influence signaling is an important theme, as is the potential for modulating signaling through therapeutic targeting of activated receptors and components of the endocytic machinery.
Collapse
Affiliation(s)
- Sanchita Mukherjee
- Department of Pathology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131-5301, USA
| | | | | |
Collapse
|
32
|
Woolfolk EA, Eguchi S, Ohtsu H, Nakashima H, Ueno H, Gerthoffer WT, Motley ED. Angiotensin II-induced activation of p21-activated kinase 1 requires Ca2+ and protein kinase Cδ in vascular smooth muscle cells. Am J Physiol Cell Physiol 2005; 289:C1286-94. [PMID: 16033904 DOI: 10.1152/ajpcell.00448.2004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
ANG II promotes remodeling of vascular smooth muscle cells (VSMCs) in cardiovascular diseases. It has been shown to activate p21-activated kinase (PAK)1, a critical component of signaling pathways implicated in growth and migration. However, the detailed signaling mechanism by which ANG II induces PAK1 activation in VSMCs remains unclear. Therefore, we have examined the mechanism required for activation of PAK1 by ANG II in VSMCs. ANG II, through activation of the ANG II type 1 receptor, rapidly promotes phosphorylation of PAK1 in VSMCs via a pathway independent of transactivation of the epidermal growth factor receptor. Using selective agonists and inhibitors, we demonstrated that mobilization of intracellular Ca2+ and PKCδ activation are required for ANG II-induced PAK1 phosphorylation. Rottlerin, a PKCδ inhibitor, significantly blocked ANG II-induced PAK1 phosphorylation. Further support for this notion was provided through infection of VSMCs with adenovirus encoding a dominant-negative (dn)PKCδ, which also markedly reduced phosphorylation of PAK1 by ANG II. In this pathway, Ca2+ acts upstream of PKCδ because a Ca2+ ionophore rapidly induced PKCδ phosphorylation at Tyr311 and Ca2+-dependent PAK1 phosphorylation was blocked by rottlerin. In addition, dnPYK-2, dnRac, and antioxidants inhibited ANG II-induced PAK1 phosphorylation, suggesting that PYK-2, Rac, and reactive oxygen species are involved in the upstream signaling. Finally, dnPAK1 markedly inhibited ANG II-induced protein synthesis in VSMCs. These data provide a novel signaling pathway by which ANG II may contribute to vascular remodeling.
Collapse
Affiliation(s)
- Elethia A Woolfolk
- Meharry Medical College, Department of Physiology, 1005 DB Todd Blvd., Nashville, TN 37208, USA
| | | | | | | | | | | | | |
Collapse
|
33
|
Affiliation(s)
- Ashok K Srivastava
- Laboratory of Cell Signaling, Research Centre, Centre hospitalier de l'Université de Montréal (CHUM)-Hôtel-Dieu and Department of Medicine, Université de Montréal, Montreal, Quebec, Canada
| |
Collapse
|