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Solanki K, Rajpoot S, Bezsonov EE, Orekhov AN, Saluja R, Wary A, Axen C, Wary K, Baig MS. The expanding roles of neuronal nitric oxide synthase (NOS1). PeerJ 2022; 10:e13651. [PMID: 35821897 PMCID: PMC9271274 DOI: 10.7717/peerj.13651] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 06/07/2022] [Indexed: 01/17/2023] Open
Abstract
The nitric oxide synthases (NOS; EC 1.14.13.39) use L-arginine as a substrate to produce nitric oxide (NO) as a by-product in the tissue microenvironment. NOS1 represents the predominant NO-producing enzyme highly enriched in the brain and known to mediate multiple functions, ranging from learning and memory development to maintaining synaptic plasticity and neuronal development, Alzheimer's disease (AD), psychiatric disorders and behavioral deficits. However, accumulating evidence indicate both canonical and non-canonical roles of NOS1-derived NO in several other tissues and chronic diseases. A better understanding of NOS1-derived NO signaling, and identification and characterization of NO-metabolites in non-neuronal tissues could become useful in diagnosis and prognosis of diseases associated with NOS1 expression. Continued investigation on the roles of NOS1, therefore, will synthesize new knowledge and aid in the discovery of small molecules which could be used to titrate the activities of NOS1-derived NO signaling and NO-metabolites. Here, we address the significance of NOS1 and its byproduct NO in modifying pathophysiological events, which could be beneficial in understanding both the disease mechanisms and therapeutics.
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Affiliation(s)
- Kundan Solanki
- Department of Biosciences and Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Simrol, Indore, India
| | - Sajjan Rajpoot
- Department of Biosciences and Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Simrol, Indore, India
| | - Evgeny E Bezsonov
- Laboratory of Cellular and Molecular Pathology of Cardiovascular System, Federal State Budgetary Scientific Institution "Petrovsky National Research Centre of Surgery", Moscow, Russia.,Laboratory of Angiopathology, Institute of General Pathology and Pathophysiology, Moscow, Russia.,Department of Biology and General Genetics, I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Alexander N Orekhov
- Laboratory of Cellular and Molecular Pathology of Cardiovascular System, Federal State Budgetary Scientific Institution "Petrovsky National Research Centre of Surgery", Moscow, Russia.,Laboratory of Angiopathology, Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - Rohit Saluja
- Department of Biochemistry, All India Institute of Medical Sciences, Bibinagar, Hyderabad, India
| | - Anita Wary
- Pharmacology and Regenerative Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Cassondra Axen
- Pharmacology and Regenerative Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Kishore Wary
- Pharmacology and Regenerative Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Mirza S Baig
- Department of Biosciences and Biomedical Engineering (BSBE), Indian Institute of Technology Indore (IITI), Simrol, Indore, India
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Suresh V, Reddy A. Dysregulation of nitric oxide synthases during early and late pathophysiological conditions of diabetes mellitus leads to amassing of microvascular impedement. J Diabetes Metab Disord 2021; 20:989-1002. [PMID: 34178871 PMCID: PMC8212285 DOI: 10.1007/s40200-021-00799-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Accepted: 04/11/2021] [Indexed: 12/20/2022]
Abstract
Diabetes is a major killer worldwide and its unprecedented rise poses a serious threat to mankind. According to recent estimation, 387 million people worldwide are affected from the disease with a prevalence rate of 8.3 and 46.3 % still remains undiagnosed. Important characteristics of diabetes are abnormalities of the physiological signalling functions of reactive oxygen species and reactive nitrogen species. Increased oxidative stress contributes to the activation of stress-sensitive intracellular signalling pathways and the development of gene products that trigger cellular damage and contribute to the vascular complications of diabetes. Growing evidence from studies into many diseases suggests that the pathogenesis of diabetes, obesity, cancer, ageing, inflammation, neurodegenerative disorders, hypertension, apoptosis, cardiovascular diseases, and heart failure are correlated with oxidative stress. This leads to cell metabolism and cell-cell homeostasis to be complexly dysregulated. This review focuses to investigate the status of oxidative stress, nitric oxide and reactive species in early and diabetes. Significance of nitric oxide synthases Evidences has accumulated indicating that the generation of reactive oxygen species (oxidative stress) may play an important role in the etiology of diabetic complications thus attention was given on the reactive oxygen and reactive nitrogen species and their potential role in pathogenesis. Additionally, the therapeutic advances in diabetes management are included. Nanotechnology, statins and stem cell technology are some techniques which can be considered to have a possible future in the treatment sector of diabetes.
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Affiliation(s)
- Varuna Suresh
- Animal Cell Culture Laboratory, Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kancheepuram District-603203, Kattankulathur, Tamil Nadu India
| | - Amala Reddy
- Animal Cell Culture Laboratory, Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kancheepuram District-603203, Kattankulathur, Tamil Nadu India
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Early Detection of Diabetic Peripheral Neuropathy: A Focus on Small Nerve Fibres. Diagnostics (Basel) 2021; 11:diagnostics11020165. [PMID: 33498918 PMCID: PMC7911433 DOI: 10.3390/diagnostics11020165] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 01/14/2021] [Accepted: 01/20/2021] [Indexed: 02/07/2023] Open
Abstract
Diabetic peripheral neuropathy (DPN) is the most common complication of both type 1 and 2 diabetes. As a result, neuropathic pain, diabetic foot ulcers and lower-limb amputations impact drastically on quality of life, contributing to the individual, societal, financial and healthcare burden of diabetes. DPN is diagnosed at a late, often pre-ulcerative stage due to a lack of early systematic screening and the endorsement of monofilament testing which identifies advanced neuropathy only. Compared to the success of the diabetic eye and kidney screening programmes there is clearly an unmet need for an objective reliable biomarker for the detection of early DPN. This article critically appraises research and clinical methods for the diagnosis or screening of early DPN. In brief, functional measures are subjective and are difficult to implement due to technical complexity. Moreover, skin biopsy is invasive, expensive and lacks diagnostic laboratory capacity. Indeed, point-of-care nerve conduction tests are convenient and easy to implement however questions are raised regarding their suitability for use in screening due to the lack of small nerve fibre evaluation. Corneal confocal microscopy (CCM) is a rapid, non-invasive, and reproducible technique to quantify small nerve fibre damage and repair which can be conducted alongside retinopathy screening. CCM identifies early sub-clinical DPN, predicts the development and allows staging of DPN severity. Automated quantification of CCM with AI has enabled enhanced unbiased quantification of small nerve fibres and potentially early diagnosis of DPN. Improved screening tools will prevent and reduce the burden of foot ulceration and amputations with the primary aim of reducing the prevalence of this common microvascular complication.
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The Impact of Hypertension and Metabolic Syndrome on Nitrosative Stress and Glutathione Metabolism in Patients with Morbid Obesity. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:1057570. [PMID: 32963689 PMCID: PMC7501544 DOI: 10.1155/2020/1057570] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 08/08/2020] [Accepted: 08/31/2020] [Indexed: 02/06/2023]
Abstract
In this pathbreaking study, we evaluated nitrosative stress in morbidly obese patients with and without metabolic syndrome. 62 women with class 3 obesity (BMI > 40 kg/m2) were divided into three subgroups: obese patients (OB), obese patients with hypertension (OB+HYP), and obese patients with metabolic syndrome (OB+MS). In comparison to the lean patients, OB had increased levels of serum myeloperoxidase (MPO), plasma nitric oxide (NO), S-nitrosothiols, and peroxynitrite (ONOO−), as well as nitrotyrosine, while oxidized glutathione (GSSG) rose only in OB+HYP group. Interestingly, ONOO− was significantly higher in OB+HYP and OB+MS as compared to OB group, while MPO only in OB+MS group. OB+MS had greater nitrotyrosine and S-nitrosothiol values than OB+HYP. Moreover, peroxynitrite could differentiate OB from OB+HYP and OB+MS (AUC 0.9292; p < 0.0001; 87.5% sensitivity, 90% specificity) as well as between OB and OB+MS group (AUC 0.9125; p < 0.0001; 81.25% sensitivity, 83.33%). In conclusion, we showed that MPO activity, NO formation, and nitrosative damage to proteins parallel the progression of metabolic disturbances of obesity. Evaluation of ONOO− concentrations may help predict the development of hypertension and metabolic syndrome in patients with morbid obesity; however, longer-term studies are required for larger numbers of patients.
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Shen H, Zhao J, Liu Y, Sun G. Interactions between and Shared Molecular Mechanisms of Diabetic Peripheral Neuropathy and Obstructive Sleep Apnea in Type 2 Diabetes Patients. J Diabetes Res 2018; 2018:3458615. [PMID: 30116739 PMCID: PMC6079583 DOI: 10.1155/2018/3458615] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 06/26/2018] [Indexed: 02/07/2023] Open
Abstract
Type 2 diabetes (T2D) accounts for about 90% of all diabetes patients and incurs a heavy global public health burden. Up to 50% of T2D patients will eventually develop neuropathy as T2D progresses. Diabetic peripheral neuropathy (DPN) is a common diabetic complication and one of the main causes of increased morbidity and mortality of T2D patients. Obstructive sleep apnea (OSA) affects over 15% of the general population and is associated with a higher prevalence of T2D. Growing evidence also indicates that OSA is highly prevalent in T2D patients probably due to diabetic peripheral neuropathy. However, the interrelations among diabetic peripheral neuropathy, OSA, and T2D hitherto have not been clearly elucidated. Numerous molecular mechanisms have been documented that underlie diabetic peripheral neuropathy and OSA, including oxidative stress, inflammation, endothelin-1, vascular endothelial growth factor (VEGF), accumulation of advanced glycation end products, protein kinase C (PKC) signaling, poly ADP ribose polymerase (PARP), nitrosative stress, plasminogen activator inhibitor-1, and vitamin D deficiency. In this review, we seek to illuminate the relationships among T2D, diabetic peripheral neuropathy, and OSA and how they interact with one another. In addition, we summarize and explain the shared molecular mechanisms involved in diabetic peripheral neuropathy and OSA for further mechanistic investigations and novel therapeutic strategies for attenuating and preventing the development and progression of diabetic peripheral neuropathy and OSA in T2D.
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Affiliation(s)
- Hong Shen
- Department of Endocrinology, The Second Hospital of Jilin University, Changchun 130041, China
| | - Junrong Zhao
- Department of Nephrology, The Second Hospital of Jilin University, Changchun 130041, China
| | - Ying Liu
- Department of Nephrology, The Second Hospital of Jilin University, Changchun 130041, China
| | - Guangdong Sun
- Department of Nephrology, The Second Hospital of Jilin University, Changchun 130041, China
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Castany S, Carcolé M, Leánez S, Pol O. The role of carbon monoxide on the anti-nociceptive effects and expression of cannabinoid 2 receptors during painful diabetic neuropathy in mice. Psychopharmacology (Berl) 2016; 233:2209-2219. [PMID: 27020787 DOI: 10.1007/s00213-016-4271-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 03/08/2016] [Indexed: 12/12/2022]
Abstract
RATIONALE The activation of cannabinoid 2 receptors (CB2R) attenuates chronic pain, but the role played by carbon monoxide synthesized by the inducible heme oxygenase 1 (HO-1) on the anti-nociceptive effects produced by a selective CB2R agonist, JWH-015, during painful diabetic neuropathy remains unknown. OBJECTIVES AND METHODS In streptozotocin (STZ)-induced diabetic mice, the anti-allodynic and anti-hyperalgesic effects of the subcutaneous administration of JWH-015 alone or combined with the intraperitoneal administration of a carbon monoxide-releasing molecule (tricarbonyldichlororuthenium(II) dimer (CORM-2)) or an HO-1 inducer compound (cobalt protoporphyrin IX (CoPP)) at 10 mg/kg were evaluated. Reversion of JWH-015 anti-nociceptive effects by the administration of an HO-1 inhibitor (tin protoporphyrin IX (SnPP)) and a CB2R antagonist (AM630) was also evaluated. Furthermore, the protein levels of HO-1, neuronal nitric oxide synthase (NOS1), and CB2R in diabetic mice treated with CORM-2 and CoPP alone or combined with JWH-015 were also assessed. RESULTS The administration of JWH-015 dose dependently inhibited hypersensitivity induced by diabetes. The effects of JWH-015 were enhanced by their coadministration with CORM-2 or CoPP and reversed by SnPP or AM630. The increased protein levels of HO-1 induced by CORM-2 and CoPP treatments were further enhanced in JWH-015-treated mice. All treatments similarly enhanced the peripheral expression of CB2R and avoided the spinal cord over-expression of NOS1 induced by diabetes. CONCLUSIONS The activation of HO-1 enhanced the anti-nociceptive effects of JWH-015 in diabetic mice, suggesting that coadministration of JWH-015 with CORM-2 or CoPP might be an interesting approach for the treatment of painful diabetic neuropathy in mice.
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Affiliation(s)
- Sílvia Castany
- Grup de Neurofarmacologia Molecular, Institut d'Investigació Biomèdica Sant Pau and Institut de Neurociències. Facultat de Medicina, Edifici M2-115, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Mireia Carcolé
- Grup de Neurofarmacologia Molecular, Institut d'Investigació Biomèdica Sant Pau and Institut de Neurociències. Facultat de Medicina, Edifici M2-115, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Sergi Leánez
- Grup de Neurofarmacologia Molecular, Institut d'Investigació Biomèdica Sant Pau and Institut de Neurociències. Facultat de Medicina, Edifici M2-115, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Olga Pol
- Grup de Neurofarmacologia Molecular, Institut d'Investigació Biomèdica Sant Pau and Institut de Neurociències. Facultat de Medicina, Edifici M2-115, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
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Cobb CA, Cole MP. Oxidative and nitrative stress in neurodegeneration. Neurobiol Dis 2015; 84:4-21. [PMID: 26024962 DOI: 10.1016/j.nbd.2015.04.020] [Citation(s) in RCA: 175] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 04/20/2015] [Accepted: 04/21/2015] [Indexed: 12/19/2022] Open
Abstract
Aerobes require oxygen for metabolism and normal free radical formation. As a result, maintaining the redox homeostasis is essential for brain cell survival due to their high metabolic energy requirement to sustain electrochemical gradients, neurotransmitter release, and membrane lipid stability. Further, brain antioxidant levels are limited compared to other organs and less able to compensate for reactive oxygen and nitrogen species (ROS/RNS) generation which contribute oxidative/nitrative stress (OS/NS). Antioxidant treatments such as vitamin E, minocycline, and resveratrol mediate neuroprotection by prolonging the incidence of or reversing OS and NS conditions. Redox imbalance occurs when the antioxidant capacity is overwhelmed, consequently leading to activation of alternate pathways that remain quiescent under normal conditions. If OS/NS fails to lead to adaptation, tissue damage and injury ensue, resulting in cell death and/or disease. The progression of OS/NS-mediated neurodegeneration along with contributions from microglial activation, dopamine metabolism, and diabetes comprise a detailed interconnected pathway. This review proposes a significant role for OS/NS and more specifically, lipid peroxidation (LPO) and other lipid modifications, by triggering microglial activation to elicit a neuroinflammatory state potentiated by diabetes or abnormal dopamine metabolism. Subsequently, sustained stress in the neuroinflammatory state overwhelms cellular defenses and prompts neurotoxicity resulting in the onset or amplification of brain damage.
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Affiliation(s)
- Catherine A Cobb
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Marsha P Cole
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Louisville, Louisville, KY 40202, USA; Department of Physiology and Biophysics, School of Medicine, University of Louisville, Louisville, KY 40202, USA.
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Ahlawat A, Rana A, Goyal N, Sharma S. Potential role of nitric oxide synthase isoforms in pathophysiology of neuropathic pain. Inflammopharmacology 2014; 22:269-78. [PMID: 25095760 DOI: 10.1007/s10787-014-0213-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 07/15/2014] [Indexed: 12/11/2022]
Abstract
Neuropathic pain triggers a cascade of events in the sensory neurons. It is the main complication of diabetes after cardiovascular disease. Nitric oxide (NO) produced from nitric oxide synthases (NOS) is an important signaling molecule which is crucial for many physiological processes such as synaptic plasticity, neuronal survival, vasodilation, vascular homeostasis, immune regulation. Overproduction of NO due to changes in NOS isoforms level involves pathological processes such as neurotoxicity, septic shock and neuropathic pain. All three isoforms of NOS as well as their end product, NO have modulatory effect on neuropathic pain. Overactivation of the N-Methyl-D-Aspartate receptor and peroxynitrite formation results in high levels of neuronal NOS (nNOS) and endothelial NOS (eNOS) which suggest that nNOS and eNOS are critical for pain hypersensitivity. Inducible NOS induced in glia by inflammation due to activation of Tumor Necrosis Factor α, Calcitonin Gene Regulating Peptide, Mitogen Activated Protein Kinases, Extracellular signal Regulated Kinase, c-Jun N-terminal kinases can induce neuronal death. This review focuses on different nitric oxide synthases and their role in pathophysiology of neuropathic pain considering NOS as an important therapeutic target.
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Al-Nimer MS, Al-Ani FS, Ali FS. Role of nitrosative and oxidative stress in neuropathy in patients with type 2 diabetes mellitus. J Neurosci Rural Pract 2012; 3:41-4. [PMID: 22346190 PMCID: PMC3271613 DOI: 10.4103/0976-3147.91932] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES Evidences of oxidative and/or nitrosative stress in type 2 diabetes mellitus were demonstrated in experimental and human studies. This study is aimed to assess the serum peroxynitrite and oxidized lipoproteins in patients with type 2 diabetes mellitus presented with clinical and laboratory evidences of peripheral neuropathy. MATERIALS AND METHODS Eighty four patients with type 2 diabetes mellitus (51 of them had neuropathy) and 31 apparent healthy subjects were studied in the unit of neurophysiology at the University Hospital of Medical College, Al-Nahrin University in Baghdad, Iraq. Neuropathy total symptom score (NTSS), neuropathy impairment score in the lower leg (NIS-LL), and nerve conduction velocity of sensory (ulnar and sural) and motor (ulnar and common peroneal) nerves were used to assess the neuropathy. Fasting venous blood was obtained from each participant for the determination of serum glucose and oxidized lipoproteins. RESULTS The electrophysiology study revealed significant decrease in conduction velocity of ulnar (sensory and motor components), sural, and common peroneal nerves in diabetic neuropathy compared to diabetics without neuropathy and healthy subjects. Significant high level of serum peroxynitrite was found in diabetic patients with or without neuropathy compared with non-diabetics. The changes in serum-oxidized lipoproteins in patients with diabetics with or without neuropathy were non-significantly differed from healthy subjects. Neither nitrosative stress nor oxidative stress indices correlated with the variables that are related to the neuropathy. CONCLUSION It concludes that evidence of nitrosative and to less extent the oxidative stress is associated with neuropathy in type 2 diabetes mellitus and their indices not correlated with variables related to neuropathy.
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Affiliation(s)
- Marwan S Al-Nimer
- Department of Pharmacology, College of Medicine, Al-Mustansiriya University, Baghdad, Iraq
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Yu X, Zhang L, Yang X, Huang H, Huang Z, Shi L, Zhang H, Du G. Salvianolic acid A protects the peripheral nerve function in diabetic rats through regulation of the AMPK-PGC1α-Sirt3 axis. Molecules 2012; 17:11216-28. [PMID: 22996345 PMCID: PMC6268602 DOI: 10.3390/molecules170911216] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 09/06/2012] [Accepted: 09/06/2012] [Indexed: 11/16/2022] Open
Abstract
Salvianolic acid A (SalA) is one of the main efficacious, water-soluble constituents of Salvia miltiorrhiza Bunge. This study investigated the protective effects of SalA on peripheral nerve in diabetic rats. Administration of SalA (0.3, 1 and 3 mg/kg, ig) was started from the 5th week after strepotozotocin (STZ60 mg/kg) intraperitoneal injection and continued for 8 weeks. Paw withdrawal mechanical threshold (PWMT) and motor nerve conduction velocity (MNCV) were used to assess peripheral nerve function. The western blot methods were employed to test the expression levels of serine-threonine liver kinase B1 (LKB1), AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1α), silent information regulator protein3 (sirtuin 3/Sirt3) and neuronal nitric oxide synthase (nNOS) in sciatic nerve. Results showed that SalA administration could increase PWMT and MNCV in diabetic rats; reduce the deterioration of sciatic nerve pathology; increase AMPK phosphorylation level, up-regulate PGC-1α, Sirt3 and nNOS expression, but had no influence on LKB1. These results suggest that SalA has protective effects against diabetic neuropathy. The beneficial effects of SalA on peripheral nerve function in diabetic rats might be attributed to improvements in glucose metabolism through regulation of the AMPK-PGC1α-Sirt3 axis.
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Affiliation(s)
- Xiaoyan Yu
- Beijing Key Laboratory of Drug Target Identification and Drug Screening, Institute of Materia Medica, Chinese Academy of Medical Science and Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050, China; (X.Y.); (L.Z.); (X.Y.); (Z.H.)
| | - Li Zhang
- Beijing Key Laboratory of Drug Target Identification and Drug Screening, Institute of Materia Medica, Chinese Academy of Medical Science and Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050, China; (X.Y.); (L.Z.); (X.Y.); (Z.H.)
| | - Xiuying Yang
- Beijing Key Laboratory of Drug Target Identification and Drug Screening, Institute of Materia Medica, Chinese Academy of Medical Science and Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050, China; (X.Y.); (L.Z.); (X.Y.); (Z.H.)
| | - Huakang Huang
- Department of Pharmacology, School of Basic Medical Science, Peking University HSC, 38 Xue Yuan Road, Beijing 100191, China;
| | - Zhonglin Huang
- Beijing Key Laboratory of Drug Target Identification and Drug Screening, Institute of Materia Medica, Chinese Academy of Medical Science and Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050, China; (X.Y.); (L.Z.); (X.Y.); (Z.H.)
| | - Lili Shi
- Tianjin Institute of Pharmaceutical Research, 308 Anshan Xidao, Nankai District, Tianjin 300193, China;
| | - Hengai Zhang
- Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China;
| | - Guanhua Du
- Beijing Key Laboratory of Drug Target Identification and Drug Screening, Institute of Materia Medica, Chinese Academy of Medical Science and Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050, China; (X.Y.); (L.Z.); (X.Y.); (Z.H.)
- Author to whom correspondence should be addressed; ; Tel./Fax: +86-010-6316-5184
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Farmer KL, Li C, Dobrowsky RT. Diabetic peripheral neuropathy: should a chaperone accompany our therapeutic approach? Pharmacol Rev 2012; 64:880-900. [PMID: 22885705 DOI: 10.1124/pr.111.005314] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Diabetic peripheral neuropathy (DPN) is a common complication of diabetes that is associated with axonal atrophy, demyelination, blunted regenerative potential, and loss of peripheral nerve fibers. The development and progression of DPN is due in large part to hyperglycemia but is also affected by insulin deficiency and dyslipidemia. Although numerous biochemical mechanisms contribute to DPN, increased oxidative/nitrosative stress and mitochondrial dysfunction seem intimately associated with nerve dysfunction and diminished regenerative capacity. Despite advances in understanding the etiology of DPN, few approved therapies exist for the pharmacological management of painful or insensate DPN. Therefore, identifying novel therapeutic strategies remains paramount. Because DPN does not develop with either temporal or biochemical uniformity, its therapeutic management may benefit from a multifaceted approach that inhibits pathogenic mechanisms, manages inflammation, and increases cytoprotective responses. Finally, exercise has long been recognized as a part of the therapeutic management of diabetes, and exercise can delay and/or prevent the development of painful DPN. This review presents an overview of existing therapies that target both causal and symptomatic features of DPN and discusses the role of up-regulating cytoprotective pathways via modulating molecular chaperones. Overall, it may be unrealistic to expect that a single pharmacologic entity will suffice to ameliorate the multiple symptoms of human DPN. Thus, combinatorial therapies that target causal mechanisms and enhance endogenous reparative capacity may enhance nerve function and improve regeneration in DPN if they converge to decrease oxidative stress, improve mitochondrial bioenergetics, and increase response to trophic factors.
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Affiliation(s)
- Kevin L Farmer
- Department of Pharmacology and Toxicology, The University of Kansas, Lawrence, KS 66045, USA
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Tahrani AA, Ali A, Raymond NT, Begum S, Dubb K, Mughal S, Jose B, Piya MK, Barnett AH, Stevens MJ. Obstructive sleep apnea and diabetic neuropathy: a novel association in patients with type 2 diabetes. Am J Respir Crit Care Med 2012; 186:434-41. [PMID: 22723291 DOI: 10.1164/rccm.201112-2135oc] [Citation(s) in RCA: 128] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
RATIONALE Diabetic peripheral neuropathy is common and causes significant morbidity. Obstructive sleep apnea (OSA) is also common in patients with type 2 diabetes. Because OSA is associated with inflammation and oxidative stress, we hypothesized that OSA is associated with peripheral neuropathy in type 2 diabetes. OBJECTIVES To assess the relationship between OSA and peripheral neuropathy in patients with type 2 diabetes. METHODS A cross-sectional study of adults with type 2 diabetes recruited randomly from the diabetes clinic of two UK hospitals. MEASUREMENTS AND MAIN RESULTS Peripheral neuropathy was diagnosed using the Michigan Neuropathy Screening Instrument. OSA (apnea-hypopnea index ≥ 5 events/h) was assessed using home-based, multichannel respiratory monitoring. Serum nitrotyrosine was measured by ELISA, lipid peroxide by spectrophotometer, and microvascular function by laser speckle contrast imaging. Two hundred thirty-four patients (mean [SD] age, 57 [12] yr) were analyzed. OSA prevalence was 65% (median apnea-hypopnea index, 7.2; range, 0-93), 40% of which were moderate to severe. Neuropathy prevalence was higher in patients with OSA than those without (60% vs. 27%, P < 0.001). After adjustment for possible confounders, OSA remained independently associated with diabetic neuropathy (odds ratio, 2.82; 95% confidence interval, 1.44-5.52; P = 0.0034). Nitrotyrosine and lipid peroxide levels (n = 102, 74 with OSA) were higher in OSA and correlated with hypoxemia severity. Cutaneous microvascular function (n = 71, 47 with OSA) was impaired in OSA. CONCLUSIONS We describe a novel independent association between diabetic peripheral neuropathy and OSA. We identified increased nitrosative/oxidative stress and impaired microvascular regulation as potential mechanisms. Prospective and interventional studies are needed to assess the impact of OSA and its treatment on peripheral neuropathy development and progression in patients with type 2 diabetes.
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Affiliation(s)
- Abd A Tahrani
- Centre of Endocrinology, Diabetes, and Metabolism, University of Birmingham, Birmingham, United Kingdom.
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Dauch JR, Yanik BM, Hsieh W, Oh SS, Cheng HT. Neuron-astrocyte signaling network in spinal cord dorsal horn mediates painful neuropathy of type 2 diabetes. Glia 2012; 60:1301-15. [PMID: 22573263 DOI: 10.1002/glia.22349] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 04/13/2012] [Accepted: 04/17/2012] [Indexed: 12/13/2022]
Abstract
Activation of the neuronal-glial network in the spinal cord dorsal horn (SCDH) mediates various chronic painful conditions. We studied spinal neuronal-astrocyte signaling interactions involved in the maintenance of painful diabetic neuropathy (PDN) in type 2 diabetes. We used the db/db mouse, an animal model for PDN of type 2 diabetes, which develops mechanical allodynia from 6 to 12 wk of age. In this study, enhanced substance P expression was detected in the presynaptic sensory fibers innervating lamina I-III in the lumbar SCDH (LSCDH) of the db/db mouse at 10 wk of age. This phenomenon is associated with enhanced spinal ERK1/2 phosphorylation in projection sensory neurons and regional astrocyte activation. In addition, peak phosphorylation of the NR1 subunit of N-methyl-D-aspartate receptor (NMDAR), along with upregulation of neuronal and inducible nitric oxide synthase (nNOS and iNOS) expression were detected in diabetic mice. Expression of nNOS and iNOS was detected in both interneurons and astrocytes in lamina I-III of the LSCDH. Treatment with MK801, an NMDAR inhibitor, inhibited mechanical allodynia, ERK1/2 phosphorylation, and nNOS and iNOS upregulation in diabetic mice. MK801 also reduced astrocytosis and glial acidic fibrillary protein upregulation in db/db mice. In addition, N(G)-nitro-L-arginine methyl ester (L-NAME), a nonspecific NOS inhibitor, had similar effects on NMDAR signaling and NOS expression. These results suggest that nitric oxide from surrounding interneurons and astrocytes interacts with NMDAR-dependent signaling in the projection neurons of the SCDH during the maintenance of PDN.
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Affiliation(s)
- Jacqueline R Dauch
- Department of Neurology, University of Michigan Medical Center, Ann Arbor, MI 48109-2200, USA
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Finkel J, Guptill V, Khaibullina A, Spornick N, Vasconcelos O, Liewehr DJ, Steinberg SM, Quezado ZM. The three isoforms of nitric oxide synthase distinctively affect mouse nocifensive behavior. Nitric Oxide 2012; 26:81-8. [PMID: 22202903 PMCID: PMC3413204 DOI: 10.1016/j.niox.2011.12.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 11/27/2011] [Accepted: 12/12/2011] [Indexed: 11/23/2022]
Abstract
Nitric oxide synthases (NOSs) have been shown to modulate thermal hyperalgesia and mechanical hypersensitivity in inflammatory and neuropathic pain. However, little is known about the effect of NOSs on baseline function of sensory nerve fibers. Using genetic deficiency and pharmacologic inhibition of NOSs, we examined the impact of the three isoforms NOS1, NOS2, and NOS3 on baseline nocifensive behavior by measuring current vocalization threshold in response to electrical stimulation at 5, 250, 2000 Hz that preferentially stimulate C, Aδ, and Aβ fibers. In response to 5, 250 and 2000 Hz, NOS1-deficient animals had significantly higher current vocalization thresholds compared with wild-type. Genetic deficiency of NOS2 was associated with higher current vocalization thresholds in response to 5 Hz (C-fiber) stimulation. In contrast, NOS3-deficient animals had an overall weak trend toward lower current vocalization thresholds at 5 Hz and significantly lower current vocalization threshold compared with wild-type animals at 250 and 2000 Hz. Therefore, NOSs distinctively affect baseline mouse current vocalization threshold and appear to play a role on nocifensive response to electrical stimulation of sensory nerve fibers.
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Affiliation(s)
- Julia Finkel
- Division of Anesthesiology and Pain Medicine, The Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Medical Center, Washington, DC 20010, United States
| | - Virginia Guptill
- Department of Perioperative Medicine, NIH Clinical Center, Bethesda, MD 20892, United States
| | - Alfia Khaibullina
- Division of Anesthesiology and Pain Medicine, The Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Medical Center, Washington, DC 20010, United States
| | - Nicholas Spornick
- Division of Anesthesiology and Pain Medicine, The Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Medical Center, Washington, DC 20010, United States
| | - Olavo Vasconcelos
- Electromyography Laboratory, Hunter Holmes McGuire Veterans Administration Medical Center, Richmond, VA, United States
| | - David J. Liewehr
- Biostatistics & Data Management Section, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States
| | - Seth M. Steinberg
- Biostatistics & Data Management Section, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States
| | - Zenaide M.N. Quezado
- Division of Anesthesiology and Pain Medicine, The Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Medical Center, Washington, DC 20010, United States
- Department of Perioperative Medicine, NIH Clinical Center, Bethesda, MD 20892, United States
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Phenotypic changes in diabetic neuropathy induced by a high-fat diet in diabetic C57BL/6 mice. EXPERIMENTAL DIABETES RESEARCH 2011; 2011:848307. [PMID: 22144990 PMCID: PMC3226416 DOI: 10.1155/2011/848307] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 08/03/2011] [Accepted: 08/25/2011] [Indexed: 01/05/2023]
Abstract
Emerging evidence suggests that dyslipidemia is an independent risk factor for diabetic neuropathy (DN) (reviewed by Vincent et al. 2009). To experimentally determine how dyslipidemia alters DN, we quantified neuropathic symptoms in diabetic mice fed a high-fat diet. Streptozotocin-induced diabetic C57BL/6 mice fed a high-fat diet developed dyslipidemia and a painful neuropathy (mechanical allodynia) instead of the insensate neuropathy (mechanical insensitivity) that normally develops in this strain. Nondiabetic mice fed a high-fat diet also developed dyslipidemia and mechanical allodynia. Thermal sensitivity was significantly reduced in diabetic compared to nondiabetic mice, but was not worsened by the high-fat diet. Moreover, diabetic mice fed a high-fat diet had significantly slower sensory and motor nerve conduction velocities compared to nondiabetic mice. Overall, dyslipidemia resulting from a high-fat diet may modify DN phenotypes and/or increase risk for developing DN. These results provide new insight as to how dyslipidemia may alter the development and phenotype of diabetic neuropathy.
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Askwith T, Zeng W, Eggo MC, Stevens MJ. Taurine reduces nitrosative stress and nitric oxide synthase expression in high glucose-exposed human Schwann cells. Exp Neurol 2011; 233:154-62. [PMID: 21952043 DOI: 10.1016/j.expneurol.2011.09.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 08/18/2011] [Accepted: 09/09/2011] [Indexed: 01/02/2023]
Abstract
The role of taurine in regulating glucose-induced nitrosative stress has been examined in human Schwann cells, a model for understanding the pathogenesis of diabetic neuropathy. Exposure to high glucose increased nitrated proteins (1.56 fold p<0.05), inducible nitric oxide synthase (iNOS) and neuronal NOS (nNOS) mRNA expression (1.55 fold and 2.2 fold respectively, p<0.05 both), phospho-p38 MAPK (1.32 fold, p<0.05) abundance and decreased Schwann cell growth (11±2%, p<0.05). Taurine supplementation prevented high-glucose induced iNOS and nNOS mRNA upregulation, reduced nitrated proteins and phospho-p38 MAPK (56±11% and 45±18% (p<0.05 both) respectively) and restored Schwann cell growth to control levels. High glucose and taurine treatment alone reduced phospho-p42/44 MAPK and phospho-AKT to below detectable levels. Treatment of human Schwann cells with donors of nitric oxide and peroxynitrite reduced taurine transporter (TauT) expression (by 35±5% and 29±7% respectively p<0.05 both) as well as the maximum velocity of taurine uptake (TauT Vmax). NOS inhibition prevented glucose-mediated TauT mRNA downregulation, and restored TauT Vmax. These data demonstrate an important role for taurine in the prevention of nitrosative stress in human Schwann cells, which may have important implications for the development and treatment of diabetic neuropathy.
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Affiliation(s)
- Trevor Askwith
- School of Clinical and Experimental Medicine, University of Birmingham, Birmingham B15 2TT, UK
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Lupachyk S, Shevalye H, Maksimchyk Y, Drel VR, Obrosova IG. PARP inhibition alleviates diabetes-induced systemic oxidative stress and neural tissue 4-hydroxynonenal adduct accumulation: correlation with peripheral nerve function. Free Radic Biol Med 2011; 50:1400-9. [PMID: 21300148 PMCID: PMC3081984 DOI: 10.1016/j.freeradbiomed.2011.01.037] [Citation(s) in RCA: 249] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 01/14/2011] [Accepted: 01/31/2011] [Indexed: 10/18/2022]
Abstract
This study evaluated the role of poly(ADP-ribose) polymerase (PARP) in systemic oxidative stress and 4-hydoxynonenal adduct accumulation in diabetic peripheral neuropathy. Control and streptozotocin-diabetic rats were maintained with or without treatment with the PARP inhibitor, 1,5-isoquinolinediol, 3 mg kg(-1) day(-1), for 10 weeks after an initial 2 weeks. Treatment efficacy was evaluated by poly(ADP-ribosyl)ated protein content in peripheral nerve and spinal cord (Western blot analysis) and dorsal root ganglion neurons and nonneuronal cells (fluorescence immunohistochemistry), as well as by indices of peripheral nerve function. Diabetic rats displayed increased urinary isoprostane and 8-hydroxy-2'-deoxyguanosine excretion (ELISA) and 4-hydroxynonenal adduct accumulation in endothelial and Schwann cells of the peripheral nerve, neurons, astrocytes, and oligodendrocytes of the spinal cord and neurons and glial cells of the dorsal root ganglia (double-label fluorescence immunohistochemistry), as well as motor and sensory nerve conduction velocity deficits, thermal hypoalgesia, and tactile allodynia. PARP inhibition counteracted diabetes-induced systemic oxidative stress and 4-hydroxynonenal adduct accumulation in peripheral nerve and spinal cord (Western blot analysis) and dorsal root ganglion neurons (perikarya, fluorescence immunohistochemistry), which correlated with improvement of large and small nerve fiber function. The findings reveal the important role of PARP activation in systemic oxidative stress and 4-hydroxynonenal adduct accumulation in diabetic peripheral neuropathy.
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Affiliation(s)
- Sergey Lupachyk
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA
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Stadler K. Peroxynitrite-driven mechanisms in diabetes and insulin resistance - the latest advances. Curr Med Chem 2011; 18:280-90. [PMID: 21110800 DOI: 10.2174/092986711794088317] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Accepted: 11/20/2010] [Indexed: 02/07/2023]
Abstract
Since its discovery, peroxynitrite has been known as a potent oxidant in biological systems, and a rapidly growing body of literature has characterized its biochemistry and role in the pathophysiology of various conditions. Either directly or by inducing free radical pathways, peroxynitrite damages vital biomolecules such as DNA, proteins including enzymes with important functions, and lipids. It also initiates diverse reactions leading eventually to disrupted cell signaling, cell death, and apoptosis. The potential role and contribution of this deleterious species has been the subject of investigation in several important diseases, including but not limited to, cancer, neurodegeneration, stroke, inflammatory conditions, cardiovascular problems, and diabetes mellitus. Diabetes, obesity, insulin resistance, and diabetes-related complications represent a major health problem at epidemic levels. Therefore, tremendous efforts have been put into investigation of the molecular basics of peroxynitrite-related mechanisms in diabetes. Studies constantly seek new therapeutical approaches in order to eliminate or decrease the level of peroxynitrite, or to interfere with its downstream mechanisms. This review is intended to emphasize the latest findings about peroxynitrite and diabetes, and, in addition, to discuss recent and novel advances that are likely to contribute to a better understanding of peroxynitrite-mediated damage in this disease.
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Affiliation(s)
- K Stadler
- Oxidative Stress and Disease Laboratory, Pennington Biomedical Research Center, LSU System, 6400 Perkins Rd, Baton Rouge, LA 70808, USA.
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Stavniichuk R, Drel VR, Shevalye H, Vareniuk I, Stevens MJ, Nadler JL, Obrosova IG. Role of 12/15-lipoxygenase in nitrosative stress and peripheral prediabetic and diabetic neuropathies. Free Radic Biol Med 2010; 49:1036-45. [PMID: 20599608 PMCID: PMC3056543 DOI: 10.1016/j.freeradbiomed.2010.06.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Revised: 06/08/2010] [Accepted: 06/14/2010] [Indexed: 01/15/2023]
Abstract
This study evaluated the role of 12/15-lipoxygenase, which converts arachidonic acid to 12(S)- and 15(S)-hydroxyeicosatetraenoic acids, in nitrosative stress in the peripheral nervous system and peripheral prediabetic and diabetic neuropathies. The experiments were performed in C57BL6/J mice made diabetic with streptozotocin or fed a high-fat diet and in human Schwann cells cultured in 5.5 or 30 mM glucose. 12/15-Lipoxygenase overexpression and activation were present in sciatic nerve and spinal cord of diabetic and high-fat diet-fed mice, as well as in human Schwann cells cultured in high concentrations of D-, but not L-glucose. 12/15-Lipoxygenase inhibition by cinnamyl-3,4-dihydroxy-alpha-cyanocinnamate (8 mg kg(-1) day(-1) sc, for 4 weeks after 12 weeks without treatment) alleviated the accumulation of nitrated proteins in the sciatic nerve and spinal cord, and large and small nerve fiber dysfunction, but not intraepidermal nerve fiber loss. 12/15-Lipoxygenase gene deficiency alleviated nitrosative stress and nerve conduction deficit, but not small sensory fiber neuropathy, in high-fat diet-fed mice. In conclusion, 12/15-lipoxygenase is implicated in nitrosative stress and peripheral neuropathy in mouse models of type 1 and early type 2 diabetes. Its presence in human Schwann cells and upregulation by high glucose suggest a potential involvement in human disease.
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Affiliation(s)
- Roman Stavniichuk
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA
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Obrosova IG. Diabetic painful and insensate neuropathy: pathogenesis and potential treatments. Neurotherapeutics 2009; 6:638-47. [PMID: 19789069 PMCID: PMC5084286 DOI: 10.1016/j.nurt.2009.07.004] [Citation(s) in RCA: 203] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2009] [Accepted: 07/09/2009] [Indexed: 12/31/2022] Open
Abstract
Advanced peripheral diabetic neuropathy (PDN) is associated with elevated vibration and thermal perception thresholds that progress to sensory loss and degeneration of all fiber types in peripheral nerve. A considerable proportion of diabetic patients also describe abnormal sensations such as paresthesias, allodynia, hyperalgesia, and spontaneous pain. One or several manifestations of abnormal sensation and pain are described in all the diabetic rat and mouse models studied so far (i.e., streptozotocin-diabetic rats and mice, type 1 insulinopenic BB/Wor and type 2 hyperinsulinemic diabetic BBZDR/Wor rats, Zucker diabetic fatty rats, and nonobese diabetic, Akita, leptin- and leptin-receptor-deficient, and high-fat diet-fed mice). Such manifestations are 1) thermal hyperalgesia, an equivalent of a clinical phenomenon described in early PDN; 2) thermal hypoalgesia, typically present in advanced PDN; 3) mechanical hyperalgesia, an equivalent of pain on pressure in early PDN; 4) mechanical hypoalgesia, an equivalent to the loss of sensitivity to mechanical noxious stimuli in advanced PDN; 5) tactile allodynia, a painful perception of a light touch; and 5) formalin-induced hyperalgesia. Rats with short-term diabetes develop painful neuropathy, whereas those with longer-term diabetes and diabetic mice typically display manifestations of both painful and insensate neuropathy, or insensate neuropathy only. Animal studies using pharmacological and genetic approaches revealed important roles of increased aldose reductase, protein kinase C, and poly(ADP-ribose) polymerase activities, advanced glycation end-products and their receptors, oxidative-nitrosative stress, growth factor imbalances, and C-peptide deficiency in both painful and insensate neuropathy. This review describes recent achievements in studying the pathogenesis of diabetic neuropathic pain and sensory disorders in diabetic animal models and developing potential pathogenetic treatments.
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Affiliation(s)
- Irina G Obrosova
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana 70808, USA.
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