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Yorek M. Treatment for Diabetic Peripheral Neuropathy: What have we Learned from Animal Models? Curr Diabetes Rev 2022; 18:e040521193121. [PMID: 33949936 PMCID: PMC8965779 DOI: 10.2174/1573399817666210504101609] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/07/2021] [Accepted: 02/13/2021] [Indexed: 11/22/2022]
Abstract
INTRODUCTION Animal models have been widely used to investigate the etiology and potential treatments for diabetic peripheral neuropathy. What we have learned from these studies and the extent to which this information has been adapted for the human condition will be the subject of this review article. METHODS A comprehensive search of the PubMed database was performed, and relevant articles on the topic were included in this review. RESULTS Extensive study of diabetic animal models has shown that the etiology of diabetic peripheral neuropathy is complex, with multiple mechanisms affecting neurons, Schwann cells, and the microvasculature, which contribute to the phenotypic nature of this most common complication of diabetes. Moreover, animal studies have demonstrated that the mechanisms related to peripheral neuropathy occurring in type 1 and type 2 diabetes are likely different, with hyperglycemia being the primary factor for neuropathology in type 1 diabetes, which contributes to a lesser extent in type 2 diabetes, whereas insulin resistance, hyperlipidemia, and other factors may have a greater role. Two of the earliest mechanisms described from animal studies as a cause for diabetic peripheral neuropathy were the activation of the aldose reductase pathway and increased non-enzymatic glycation. However, continuing research has identified numerous other potential factors that may contribute to diabetic peripheral neuropathy, including oxidative and inflammatory stress, dysregulation of protein kinase C and hexosamine pathways, and decreased neurotrophic support. In addition, recent studies have demonstrated that peripheral neuropathy-like symptoms are present in animal models, representing pre-diabetes in the absence of hyperglycemia. CONCLUSION This complexity complicates the successful treatment of diabetic peripheral neuropathy, and results in the poor outcome of translating successful treatments from animal studies to human clinical trials.
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Affiliation(s)
- Mark Yorek
- Department of Internal Medicine, University of Iowa, Iowa City, IA, 52242 USA
- Department of Veterans Affairs Iowa City Health Care System, Iowa City, IA, 52246 USA
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, IA, 52242 USA
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Aldose Reductase and the Polyol Pathway in Schwann Cells: Old and New Problems. Int J Mol Sci 2021; 22:ijms22031031. [PMID: 33494154 PMCID: PMC7864348 DOI: 10.3390/ijms22031031] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/13/2021] [Accepted: 01/19/2021] [Indexed: 12/13/2022] Open
Abstract
Aldose reductase (AR) is a member of the reduced nicotinamide adenosine dinucleotide phosphate (NADPH)-dependent aldo-keto reductase superfamily. It is also the rate-limiting enzyme of the polyol pathway, catalyzing the conversion of glucose to sorbitol, which is subsequently converted to fructose by sorbitol dehydrogenase. AR is highly expressed by Schwann cells in the peripheral nervous system (PNS). The excess glucose flux through AR of the polyol pathway under hyperglycemic conditions has been suggested to play a critical role in the development and progression of diabetic peripheral neuropathy (DPN). Despite the intensive basic and clinical studies over the past four decades, the significance of AR over-activation as the pathogenic mechanism of DPN remains to be elucidated. Moreover, the expected efficacy of some AR inhibitors in patients with DPN has been unsatisfactory, which prompted us to further investigate and review the understanding of the physiological and pathological roles of AR in the PNS. Particularly, the investigation of AR and the polyol pathway using immortalized Schwann cells established from normal and AR-deficient mice could shed light on the causal relationship between the metabolic abnormalities of Schwann cells and discordance of axon-Schwann cell interplay in DPN, and led to the development of better therapeutic strategies against DPN.
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Bashir SO. Concomitant administration of resveratrol and insulin protects against diabetes mellitus type-1-induced renal damage and impaired function via an antioxidant-mediated mechanism and up-regulation of Na +/K +-ATPase. Arch Physiol Biochem 2019; 125:104-113. [PMID: 29436859 DOI: 10.1080/13813455.2018.1437752] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This study investigated if a combination of resveratrol (RES) and insulin could reverse type 1 diabetic mellitus-induced (T1DM) nephropathy and illustrates mechanism of action. Rats were divided into six groups (n = 10/group) as follows: control, control + RES (20 mg/kg), T1DM, T1DM + RES, T1DM + insulin (1 U/g), and T1DM + RES + insulin and treated for eight weeks. While individual administrations of both drugs significantly but partially restored renal function and cortex architectures, combination therapy of both RES and insulin produced the maximum improvements. Mechanism of actions revealed a synergist effect of both drugs due to hypoglycaemic effect of insulin and the ability of both drugs to increase renal cortex antioxidant enzymes activities, inhibit lipid peroxidation, and up-regulate Na+/K+-ATPase, independent of each others. In conclusion, these data suggest the combined therapy with insulin and RES could provide an excellent combined drug therapy against T1DM-induced nephropathy.
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Affiliation(s)
- Salah O Bashir
- a Department of Physiology, College of Medicine , King Khalid University , Abha , Saudi Arabia
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Chen H, Nie Q, Hu J, Huang X, Zhang K, Nie S. Glucomannans Alleviated the Progression of Diabetic Kidney Disease by Improving Kidney Metabolic Disturbance. Mol Nutr Food Res 2019; 63:e1801008. [DOI: 10.1002/mnfr.201801008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 03/13/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Haihong Chen
- State Key Laboratory of Food Science and TechnologyNanchang University Nanchang 330047 China
| | - Qixing Nie
- State Key Laboratory of Food Science and TechnologyNanchang University Nanchang 330047 China
| | - Jielun Hu
- State Key Laboratory of Food Science and TechnologyNanchang University Nanchang 330047 China
| | - Xiaojun Huang
- State Key Laboratory of Food Science and TechnologyNanchang University Nanchang 330047 China
| | - Ke Zhang
- State Key Laboratory of Food Science and TechnologyNanchang University Nanchang 330047 China
| | - Shaoping Nie
- State Key Laboratory of Food Science and TechnologyNanchang University Nanchang 330047 China
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He J, Gao HX, Yang N, Zhu XD, Sun RB, Xie Y, Zeng CH, Zhang JW, Wang JK, Ding F, Aa JY, Wang GJ. The aldose reductase inhibitor epalrestat exerts nephritic protection on diabetic nephropathy in db/db mice through metabolic modulation. Acta Pharmacol Sin 2019; 40:86-97. [PMID: 29930278 DOI: 10.1038/s41401-018-0043-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 04/17/2018] [Indexed: 01/06/2023] Open
Abstract
Epalrestat is an inhibitor of aldose reductase in the polyol pathway and is used for the management of diabetic neuropathy clinically. Our pilot experiments and accumulated evidences showed that epalrestat inhibited polyol pathway and reduced sorbitol production, and suggested the potential renal protection effects of epalrestat on diabetic nephropathy (DN). To evaluate the protective effect of epalrestat, the db/db mice were used and exposed to epalrestat for 8 weeks, both the physiopathological condition and function of kidney were examined. For the first time, we showed that epalrestat markedly reduced albuminuria and alleviated the podocyte foot process fusion and interstitial fibrosis of db/db mice. Metabolomics was employed, and metabolites in the plasma, renal cortex, and urine were profiled using a gas chromatography-mass spectrometry (GC/MS)-based metabolomic platform. We observed an elevation of sorbitol and fructose, and a decrease of myo-inositol in the renal cortex of db/db mice. Epalrestat reversed the renal accumulation of the polyol pathway metabolites of sorbitol and fructose, and increased myo-inositol level. Moreover, the upregulation of aldose reductase, fibronectin, collagen III, and TGF-β1 in renal cortex of db/db mice was downregulated by epalrestat. The data suggested that epalrestat has protective effects on DN, and the inhibition of aldose reductase and the modulation of polyol pathway in nephritic cells be a potentially therapeutic strategy for DN.
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Sloan G, Shillo P, Selvarajah D, Wu J, Wilkinson ID, Tracey I, Anand P, Tesfaye S. A new look at painful diabetic neuropathy. Diabetes Res Clin Pract 2018; 144:177-191. [PMID: 30201394 DOI: 10.1016/j.diabres.2018.08.020] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 08/24/2018] [Indexed: 02/06/2023]
Abstract
The prevalence of diabetes mellitus and its chronic complications continue to increase alarmingly. Consequently, the massive expenditure on diabetic distal symmetrical polyneuropathy (DSPN) and its sequelae, will also likely rise. Up to 50% of patients with diabetes develop DSPN, and about 20% develop neuropathic pain (painful-DSPN). Painful-DSPN can cast a huge burden on sufferers' lives with increased rates of unemployment, mental health disorders and physical co-morbidities. Unfortunately, due to limited understanding of the mechanisms leading to painful-DSPN, current treatments remain inadequate. Recent studies examining the pathophysiology of painful-DSPN have identified maladaptive alterations at the level of both the peripheral and central nervous systems. Additionally, genetic studies have suggested that patients with variants of voltage gated sodium channels may be more at risk of developing neuropathic pain in the presence of a disease trigger such as diabetes. We review the recent advances in genetics, skin biopsy immunohistochemistry and neuro-imaging, which have the potential to further our understanding of the condition, and identify targets for new mechanism based therapies.
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Affiliation(s)
- Gordon Sloan
- Diabetes Research Unit, Sheffield Teaching Hospitals NHS Foundation Trust & Academic Unit of Radiology, University of Sheffield, Sheffield, United Kingdom
| | - Pallai Shillo
- Diabetes Research Unit, Sheffield Teaching Hospitals NHS Foundation Trust & Academic Unit of Radiology, University of Sheffield, Sheffield, United Kingdom
| | - Dinesh Selvarajah
- Diabetes Research Unit, Sheffield Teaching Hospitals NHS Foundation Trust & Academic Unit of Radiology, University of Sheffield, Sheffield, United Kingdom
| | - Jing Wu
- Department of Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Iain D Wilkinson
- Diabetes Research Unit, Sheffield Teaching Hospitals NHS Foundation Trust & Academic Unit of Radiology, University of Sheffield, Sheffield, United Kingdom
| | - Irene Tracey
- FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Praveen Anand
- Peripheral Neuropathy Unit, Centre for Clinical Translation, Imperial College London, Hammersmith Hospital, London, United Kingdom
| | - Solomon Tesfaye
- Diabetes Research Unit, Sheffield Teaching Hospitals NHS Foundation Trust & Academic Unit of Radiology, University of Sheffield, Sheffield, United Kingdom.
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Nutritional and Acquired Deficiencies in Inositol Bioavailability. Correlations with Metabolic Disorders. Int J Mol Sci 2017; 18:ijms18102187. [PMID: 29053604 PMCID: PMC5666868 DOI: 10.3390/ijms18102187] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 10/09/2017] [Accepted: 10/17/2017] [Indexed: 01/02/2023] Open
Abstract
Communities eating a western-like diet, rich in fat, sugar and significantly deprived of fibers, share a relevant increased risk of both metabolic and cancerous diseases. Even more remarkable is that a low-fiber diet lacks some key components—as phytates and inositols—for which a mechanistic link has been clearly established in the pathogenesis of both cancer and metabolic illness. Reduced bioavailability of inositol in living organisms could arise from reduced food supply or from metabolism deregulation. Inositol deregulation has been found in a number of conditions mechanistically and epidemiologically associated to high-glucose diets or altered glucose metabolism. Indeed, high glucose levels hinder inositol availability by increasing its degradation and by inhibiting both myo-Ins biosynthesis and absorption. These underappreciated mechanisms may likely account for acquired, metabolic deficiency in inositol bioavailability.
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Zhang X, Fang C, Li X, Cao YJ, Zhang QL, Zhang HH, Huang Y, Hu J, Liu CF. Clinical characteristics and risk factors of diabetic peripheral neuropathy of type 1 diabetes mellitus patients. Diabetes Res Clin Pract 2017; 129:97-104. [PMID: 28521198 DOI: 10.1016/j.diabres.2017.04.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Revised: 03/25/2017] [Accepted: 04/19/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND Small nerve fibers are more easily injured than large ones for diabetic peripheral neuropathy (DPN). The study investigated the characteristics and related risk factors of DPN of T1DM patients using nerve conduction velocity and CPT values, which provided evidences for its early diagnosis. METHODS 70 T1DM patients and 48 healthy volunteers were included. All subjects accepted nerve conduction velocity and CPT examinations for four limbs. Detailed clinical indicators were recorded. CPT values were compared between TIDM group and control group. The risk factors affecting DPN were further explored. RESULTS Compared with the control group, CPT values under three frequencies were decreased in T1DM group. The abnormality rate of sural nerves was higher than that of median nerves (P<0.001). Median nerve dysfunction mainly presented as hypoesthesia under 250Hz and 5Hz current stimulus. And sural nerve dysfunction mainly presented as hyperesthesia under three frequencies. Compared with left median nerve, abnormal rate of right median nerve was higher under 2000Hz current stimulus (P=0.035). However, abnormal rate of left sural nerve was higher than that of right side under 250Hz and 5Hz current stimulus (P=0.001, <0.001). Duration, NDS scores and CPT values of right median nerve under 2000Hz current stimulus were independent risk factors of abnormal nerve conduction velocity. CONCLUSIONS The study proved that DPN of T1DM are mainly lower limb-injured., amyelinated and thin myelinated nerve fiber-involved. CPT can be combined with traditional nerve conduction velocity examination, which will help the diagnosis of DPN of T1DM earlier and more comprehensively.
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Affiliation(s)
- Xia Zhang
- Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Chen Fang
- Department of Endocrinology, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Xiang Li
- Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Yong-Jun Cao
- Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Qi-Lin Zhang
- Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Hong-Hong Zhang
- Department of Endocrinology, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Yun Huang
- Department of Endocrinology, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China
| | - Ji Hu
- Department of Endocrinology, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China.
| | - Chun-Feng Liu
- Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China.
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9
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Briffa JF, Grinfeld E, Jenkin KA, Mathai ML, Poronnik P, McAinch AJ, Hryciw DH. Diet induced obesity in rats reduces NHE3 and Na(+) /K(+) -ATPase expression in the kidney. Clin Exp Pharmacol Physiol 2016; 42:1118-26. [PMID: 26173747 DOI: 10.1111/1440-1681.12452] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Revised: 06/25/2015] [Accepted: 07/01/2015] [Indexed: 01/25/2023]
Abstract
The consumption of a high fat diet (HFD) is associated with proteinuria and altered sodium handling and excretion, which can lead to kidney disease. In the proximal tubule, the Na(+) /H(+) Exchanger 3 (NHE3) is responsible for normal protein reabsorption and the reabsorption of approximately 70% of the renal sodium load. It is the Na(+) /K(+) -ATPase that provides the driving force for the reabsorption of sodium and its exit across the basolateral membrane. This study investigates the effects that consumption of a HFD for 12 weeks has on NHE3 and Na(+) /K(+) -ATPase expression in the kidney. Western blot analysis identified a significant reduction in NHE3 and its modulator, phosphorylated protein kinase B, in renal lysate from obese rats. In the obese rats, a reduction in NHE3 expression in the proximal tubule may impact on the acidification of endosomes which are responsible for albumin uptake, suggesting a key role for the exchanger in protein endocytosis in obesity. Western blot analysis identified a reduction in Na(+) /K(+) -ATPase which could also potentially impact on albumin uptake and sodium reabsorption. This study demonstrates that consumption of a HFD for 12 weeks reduces renal NHE3 and Na(+) /K(+) -ATPase expression, an effect that may contribute to the albuminuria associated with obesity. Furthermore the reduction in these transporters is not likely to contribute to the reduced sodium excretion in obesity. These data highlight a potential link between NHE3 and Na(+) /K(+) -ATPase in the pathophysiological changes in renal protein handling observed in obesity.
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Affiliation(s)
- J F Briffa
- Centre for Chronic Disease Prevention and Management, College of Health and Biomedicine, Victoria University, St Albans, Victoria, Australia.,Department of Physiology, The University of Melbourne, Parkville, Victoria, Australia
| | - E Grinfeld
- Centre for Chronic Disease Prevention and Management, College of Health and Biomedicine, Victoria University, St Albans, Victoria, Australia
| | - K A Jenkin
- Centre for Chronic Disease Prevention and Management, College of Health and Biomedicine, Victoria University, St Albans, Victoria, Australia
| | - M L Mathai
- Centre for Chronic Disease Prevention and Management, College of Health and Biomedicine, Victoria University, St Albans, Victoria, Australia
| | - P Poronnik
- Department of Physiology, School of Medical Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - A J McAinch
- Centre for Chronic Disease Prevention and Management, College of Health and Biomedicine, Victoria University, St Albans, Victoria, Australia
| | - D H Hryciw
- Department of Physiology, The University of Melbourne, Parkville, Victoria, Australia
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Chang HH, Chao HN, Walker CS, Choong SY, Phillips A, Loomes KM. Renal depletion of myo-inositol is associated with its increased degradation in animal models of metabolic disease. Am J Physiol Renal Physiol 2015; 309:F755-63. [DOI: 10.1152/ajprenal.00164.2015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 08/18/2015] [Indexed: 12/20/2022] Open
Abstract
Renal depletion of myo-inositol (MI) is associated with the pathogenesis of diabetic nephropathy in animal models, but the underlying mechanisms involved are unclear. We hypothesized that MI depletion was due to changes in inositol metabolism and therefore examined the expression of genes regulating de novo biosynthesis, reabsorption, and catabolism of MI. We also extended the analyses from diabetes mellitus to animal models of dietary-induced obesity and hypertension. We found that renal MI depletion was pervasive across these three distinct disease states in the relative order: hypertension (−51%) > diabetes mellitus (−35%) > dietary-induced obesity (−19%). In 4-wk diabetic kidneys and in kidneys derived from insulin-resistant and hypertensive rats, MI depletion was correlated with activity of the MI-degrading enzyme myo-inositol oxygenase (MIOX). By contrast, there was decreased MIOX expression in 8-wk diabetic kidneys. Immunohistochemistry localized the MI-degrading pathway comprising MIOX and the glucuronate-xylulose (GX) pathway to the proximal tubules within the renal cortex. These findings indicate that MI depletion could reflect increased catabolism through MIOX and the GX pathway and implicate a common pathological mechanism contributing to renal oxidative stress in metabolic disease.
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Affiliation(s)
- H.-H. Chang
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - H.-N. Chao
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - C. S. Walker
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - S.-Y. Choong
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - A. Phillips
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
| | - K. M. Loomes
- School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand
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Ahmed MM, Mosalem DM, Tarshouby WA, Alfeeli AK, Baqer AB, Mohamed MH. Computerized Dynamic Posturography in Patients with Diabetic Peripheral Neuropathy and Visual Feedback-Based Balance Training Effects. Open Access Maced J Med Sci 2014. [DOI: 10.3889/oamjms.2014.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND: Diabetic peripheral neuropathy (DPN) often has reduced stability during standing conditions.AIM: To compare balance control in diabetic patients and normal subjects using computerized dynamic posturography and to assess effect of visual feedback-based balance training in DPN.MATERIALS AND METHODS: A total of 57 patients of type 2 diabetes mellitus and 30 age-matched normal control subjects were recruited. The sensory organization test was done before and after the training program.RESULTS: There was a significant decrease of mean (± SD) of composite equilibrium score and somatosensory ratio score between subgroups of DPN and control healthy group (p < 0.05). There was a significant increase of mean (± SD) of composite equilibrium score and the somatosensory ratio score after treatment as compared to results before training (p < 0.05) in mild DPN. Moreover, there were a significant correlation between composite equilibrium score and disease duration before training in the severe DPN (r = 0.368, p < 0.05). CONCLUSIONS: Computerized dynamic posturography is an important quantitative tool in the assessment of posture instability and allows for early disclosure of the failure of the postural control system. Visual feedback-based balance training was shown to be a promising method for fall prevention among early diabetes mellitus with peripheral neuropathy.
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Diabetic peripheral neuropathy: Current perspective and future directions. Pharmacol Res 2014; 80:21-35. [DOI: 10.1016/j.phrs.2013.12.005] [Citation(s) in RCA: 201] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 11/26/2013] [Accepted: 12/16/2013] [Indexed: 01/17/2023]
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Das-Evcimen N, Sarikaya M, Gurkok G, Suzen S. Evaluation of rat kidney aldose reductase inhibitory activity of some N-acetyl dehydroalanine derivatives. Med Chem Res 2011. [DOI: 10.1007/s00044-010-9337-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Yang B, Hodgkinson A, Millward BA, Demaine AG. Polymorphisms of myo-inositol oxygenase gene are associated with Type 1 diabetes mellitus. J Diabetes Complications 2010; 24:404-8. [PMID: 19896870 DOI: 10.1016/j.jdiacomp.2009.09.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Accepted: 09/28/2009] [Indexed: 11/20/2022]
Abstract
Myo-inositol oxygenase (MIOX) is the first and rate-limiting enzyme in myo-inositol (MI) metabolism pathway. The increase in MIOX enzyme activity is in proportion to serum glucose concentrations and may be responsible for the MI depletion found in the diabetic complications. The aim was to investigate whether single nucleotide polymorphisms (SNPs) in the MIOX gene are associated with Type 1 diabetes mellitus (T1D) and its complications. Four hundred thirty Caucasian patients with T1D were recruited: 172 patients had diabetic nephropathy, 140 had diabetic retinopathy/neuropathy, 118 patients had diabetes for ≥20 years without microvascular complications and 224 were normal controls. Three SNPs, rs761745 (C/T), and rs2232873 (A/G) in the promoter and rs1055271 (C/G) in the 3'-untranslated were genotyped commercially. The frequencies of the CC genotype (0.36 vs. 0.44; P=.034) and C allele (0.60 vs. 0.68; P=.011) of rs761745 were significantly lower in patients with T1D compared with normal controls. Patients with T1D had a decreased frequency of the combination genotypes of CC (rs761745), GG (rs2232873) and GC (rs1055271) compared with the normal controls (0.13 vs. 0.22, P=.0027, Pc=0.014). The haplotypes with C/G/G and C/G/C were less common in patients with T1D compared to normal controls (0.59 vs. 0.70, P=.021) and the haplotypes with T/G/C and T/G/G ware more common in patients with T1D compared to normal controls (0.37 vs. 0.26; P=.021). In summary, our results demonstrated that the polymorphism (rs761745) in the promoter region of MIOX gene may be associated with the development of T1D in our studied population.
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Affiliation(s)
- Bingmei Yang
- Molecular Medicine Research Group, Institute of Biomedical and Clinical Science, Peninsula Medical School, Tamar Science Park, PL6 8BU Plymouth, UK.
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Baluchnejadmojarad T, Roghani M, Khastehkhodaie Z. Chronic treatment of silymarin improves hyperalgesia and motor nerve conduction velocity in diabetic neuropathic rat. Phytother Res 2010; 24:1120-5. [PMID: 19960427 DOI: 10.1002/ptr.3078] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The effect of chronic silymarin (SM) treatment on hyperalgesia, sciatic motor nerve conduction velocity (MNCV) and oxidative stress in streptozotocin (STZ)-diabetic neuropathic rat was evaluated. Rats were divided into control, diabetic, SM-treated control and diabetic, and sodium salisylate (SS)-treated control and diabetic. SM was administered daily at a dose of 100 mg/kg for two months. Finally, hyperalgesia and sciatic MNCV and oxidative stress markers were assessed. Diabetic rats showed a significant deficit in MNCV and markedly exhibited chemical and thermal hyperalgesia, indicating development of diabetic neuropathy. Antioxidant enzyme superoxide dismutase (SOD) level significantly reduced and malondialdehyde (MDA) level significantly increased in diabetic rats compared to control rats; SM treatment significantly ameliorated the alteration in MNCV, hyperalgesia, MDA level and antioxidant enzyme SOD in diabetic rats. These results clearly suggest the potential effect of SM in prevention and treatment of diabetic neuropathy.
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Lanaspa MA, Andres-Hernando A, Rivard CJ, Dai Y, Li N, Berl T. ZAC1 is up-regulated by hypertonicity and decreases sorbitol dehydrogenase expression, allowing accumulation of sorbitol in kidney cells. J Biol Chem 2009; 284:19974-81. [PMID: 19423711 PMCID: PMC2740423 DOI: 10.1074/jbc.m109.001792] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 05/01/2009] [Indexed: 01/09/2023] Open
Abstract
Affymetrix GeneChip technology was employed to detect differentially expressed genes in inner medullary collecting duct (IMCD3) cells grown under isotonic and hypertonic conditions. A marked up-regulation was found for the zinc-finger protein ZAC1 under hypertonic stress (219-fold, p < 0.001). Changes in expression for ZAC1 were verified by quantitative PCR for message and Western blotting for protein. In mouse and human kidney tissues, ZAC1 expression was substantial in the papilla and was absent in the cortex. Furthermore, ZAC1 expression significantly increased in the papilla of mice following 36 h of fluid restriction and decreased in polyuric mice consuming sucrose in water. Because ZAC1 has been described to be a potential negative regulator of sorbitol dehydrogenase (SDH) in hippocampal cells, we examined whether this relationship also occurs in kidney cells under hypertonic stress. We found that stable IMCD3 clones silenced for ZAC1 to varying levels demonstrated an inverse effect on SDH expression. ZAC1 binds to a consensus repression site within the promoter of SDH, pointing to a mechanism whereby ZAC1 acts by repressing SDH transcriptional activity during hypertonic conditions. Taken together, these data strongly suggest that ZAC1 is up-regulated under hypertonic stress and negatively regulates expression of SDH, allowing for accumulation of sorbitol as a compatible organic osmolyte.
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Affiliation(s)
- Miguel A. Lanaspa
- From the Department of Renal Diseases and Hypertension, University of Colorado Health Sciences Center, Aurora, Colorado 80045
| | - Ana Andres-Hernando
- From the Department of Renal Diseases and Hypertension, University of Colorado Health Sciences Center, Aurora, Colorado 80045
| | - Christopher J. Rivard
- From the Department of Renal Diseases and Hypertension, University of Colorado Health Sciences Center, Aurora, Colorado 80045
| | - Yue Dai
- From the Department of Renal Diseases and Hypertension, University of Colorado Health Sciences Center, Aurora, Colorado 80045
| | - Nanxing Li
- From the Department of Renal Diseases and Hypertension, University of Colorado Health Sciences Center, Aurora, Colorado 80045
| | - Tomas Berl
- From the Department of Renal Diseases and Hypertension, University of Colorado Health Sciences Center, Aurora, Colorado 80045
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Thirteen-month inhibition of aldose reductase by zenarestat prevents morphological abnormalities in the dorsal root ganglia of streptozotocin-induced diabetic rats. Brain Res 2008; 1247:182-7. [PMID: 18992730 DOI: 10.1016/j.brainres.2008.10.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 09/29/2008] [Accepted: 10/04/2008] [Indexed: 11/23/2022]
Abstract
The dorsal root ganglia (DRG) have been identified as the target tissue in diabetic somatosensory neuropathy. It has been reported that, in the chronically diabetic state, DRG sensory neurons may undergo morphological changes. In this study, we examined the effect of zenarestat, an aldose reductase inhibitor, on the morphological derangement of the DRG and the sural nerve of streptozotocin-induced diabetic rats (STZ rats) over a 13-month period. The cell area of the DRG in STZ rats was smaller than that in normal rats. A decrease in fiber size was apparent in the sural nerve of the STZ rats, and the fiber density was greater. These morphological changes were reversed in zenarestat-treated STZ rats. The data suggest that, in peripheral sensory diabetic neuropathy, hyperactivation of the polyol pathway induces abnormalities not only in peripheral nerve fiber, but also in the DRG, which is an aggregate of primary sensory afferent cell bodies.
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18
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C-Peptide effects on renal physiology and diabetes. EXPERIMENTAL DIABETES RESEARCH 2008; 2008:281536. [PMID: 18509500 PMCID: PMC2396455 DOI: 10.1155/2008/281536] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2007] [Accepted: 04/10/2008] [Indexed: 02/07/2023]
Abstract
The C-peptide of proinsulin is important for the biosynthesis of insulin and has for a long time been considered to be biologically inert. Animal studies have shown that some of the renal effects of the C-peptide may in part be explained by its ability to stimulate the Na,K-ATPase activity. Precisely, the C-peptide reduces diabetes-induced glomerular hyperfiltration both in animals and humans, therefore, resulting in regression of fibrosis. The tubular function is also concerned as diabetic animals supplemented with C-peptide exhibit better renal function resulting in reduced urinary sodium waste and protein excretion together with the reduction of the diabetes-induced glomerular hyperfiltration. The tubular effectors of C-peptide were considered to be tubule transporters, but recent studies have shown that biochemical pathways involving cellular kinases and inflammatory pathways may also be important. The matter theory concerning the C-peptide effects is a metabolic one involving the effects of the C-peptide on lipidic metabolic status.This review concentrates on the most convincing data which indicate that the C-peptide is a biologically active hormone for renal physiology.
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19
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Pitel S, Raccah D, Gerbi A, Pieroni G, Vague P, Coste TC. At low doses, a gamma-linolenic acid-lipoic acid conjugate is more effective than docosahexaenoic acid-enriched phospholipids in preventing neuropathy in diabetic rats. J Nutr 2007; 137:368-72. [PMID: 17237313 DOI: 10.1093/jn/137.2.368] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A deficiency in essential fatty acid metabolism has been reported in diabetes. Nutritional supplementations with (n-6) or (n-3) PUFA have differential efficiency on parameters of diabetic neuropathy, including nerve conduction velocity (NCV) and nerve blood flow (NBF). The aim of this study was to compare the neuroprotective effects of gamma-linolenic acid (GLA)-lipoic acid (LA) conjugate (GLA-LA) and docosahexaenoic acid (DHA)-enriched phospholipids (PL) supplementations on NCV and NBF. Streptozotocin-induced diabetic (D) and control (C) rats were supplemented for 8 wk with either DHA-enriched PL at a dose of 30 mg.kg-1.d-1 (DDHA and CDHA) or with corn oil enriched with GLA-LA at a dose of 30 mg.kg-1.d-1 (DGLA and CGLA). Moreover, a C and D group received no supplementation. After 8 wk, NCV (-30%) and NBF (-50%) were lower in the D group than in the C group. Supplementation with GLA-LA totally prevented the decrease in NCV and NBF in the DGLA group, in which values did not differ from group C. Supplementation with DHA only partially prevented the decrease in NCV in the DDHA group, in which value was different from groups C and D and did not affect NBF. We conclude that at the low doses used, supplementation with GLA-LA is more effective than supplementation with DHA in preventing experimental diabetic neuropathy. The difference could be due in part to an antioxidant protective effect of LA on GLA.
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Affiliation(s)
- Séverine Pitel
- UPRES EA 2193, Aix-Marseille Université, Faculté de Médecine, IPHM-IFR 125, Marseille, F-13385 France
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20
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Kuzumoto Y, Kusunoki S, Kato N, Kihara M, Low PA. Effect of the aldose reductase inhibitor fidarestat on experimental diabetic neuropathy in the rat. Diabetologia 2006; 49:3085-93. [PMID: 17063327 DOI: 10.1007/s00125-006-0400-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2005] [Accepted: 06/30/2006] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS Fidarestat, an aldose reductase inhibitor (ARI), has been reported to improve clinical symptoms and nerve conduction deficits in human diabetic neuropathy. We evaluated the dose-dependency and some of the mechanisms of the drug action in experimental diabetic neuropathy (EDN). METHODS Control rats and rats with EDN were fed on normal pellets or pellets containing 0.00066% (1 mg/kg) or 0.00263% (4 mg/kg) fidarestat for 10 weeks. We evaluated the effect of fidarestat on nerve blood flow (NBF), electrophysiology, and sorbitol and fructose content in sciatic nerve in control and diabetic rats. For detection of oxidative stress in peripheral nerve, we measured sciatic nerve reduced glutathione (GSH) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) immunolabelling of dorsal root ganglion (DRG) neurons. RESULTS NBF, compound muscle action potential and amplitude of C-potential were significantly improved in diabetic rats fed on the diet supplemented with fidarestat. Fidarestat suppressed the increase in sorbitol and fructose, normalised GSH in sciatic nerve, and reduced the number of 8-OHdG-positive cells in DRG. CONCLUSIONS/INTERPRETATION Fidarestat improves neuropathy, presumably via an improvement in oxidative stress. This study supports a role for fidarestat in the treatment of diabetic neuropathy.
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Affiliation(s)
- Y Kuzumoto
- Department of Neurology, Kinki University, School of Medicine, 377-2 Ohno-Higashi Osaka-Sayama, Osaka, Japan.
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21
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Arner RJ, Prabhu KS, Krishnan V, Johnson MC, Reddy CC. Expression of myo-inositol oxygenase in tissues susceptible to diabetic complications. Biochem Biophys Res Commun 2005; 339:816-20. [PMID: 16332355 DOI: 10.1016/j.bbrc.2005.11.090] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2005] [Accepted: 11/13/2005] [Indexed: 11/29/2022]
Abstract
Alterations of intracellular levels of myo-inositol (MI) have the potential to impact such cellular processes as signaling pathways and osmotic balance. Depletion of MI has been implicated in the etiology of diabetic complications; however, the mechanistic details remain sketchy. myo-Inositol oxygenase (MIOX-EC 1.13.99.1) catalyzes the first committed step of the only pathway of MI catabolism. In the present study, extra-renal tissues and cell types, including those affected by diabetic complications, were examined for MIOX expression. Western blotting results indicated that kidney is the only major organ where MIOX protein is expressed at detectable levels. Immunohistochemical examination of the kidney revealed that the proximal tubular epithelial cells are the only site of MIOX expression in the kidney. Reverse-transcription-polymerase chain reaction (RT-PCR) and Western immunoblot analyses, however, revealed that the cell lines ARPE-19 and HLE-B3, representing human retinal pigmented epithelium and lens epithelium, respectively, also express MIOX. In addition, quantitative real-time RT-PCR analysis of all major tissues in the mouse showed that the sciatic nerve contained MIOX transcript, which was found to be significantly higher than that observed in other non-renal organs. These results indicate that MIOX is found at lower levels in extra-renal tissues where diabetic complications, including nephropathy, neuropathy, retinopathy, and cataract, are frequently observed.
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Affiliation(s)
- Ryan J Arner
- Department of Veterinary and Biomedical Sciences, The Center for Molecular Toxicology and Carcinogenesis, 115 Henning Building, The Pennsylvania State University, University Park, PA 16802, USA
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22
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De Miranda Neto MH, Defani MA, Fregonesi CEPT, Natali MRM, Pereira A. Morphometric and quantitative evaluation of the NADH-diaphorase positive myenteric neurons of the jejunum of streptozotocin-diabetic rats supplemented with acetyl-L-carnitine. Anat Histol Embryol 2005; 34:154-8. [PMID: 15929729 DOI: 10.1111/j.1439-0264.2005.00585.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Summary In this study we investigated the effect of the acetyl-L-carnitine (ALC) supplementation on the myenteric neurons of the jejunum of rats made diabetic at the age of 105 days by streptozotocin (35 mg/kg body weight). Four groups were used: non-diabetic (C), non-diabetic supplemented with ALC (CC), diabetic (D), diabetic supplemented with ALC (DC). After 15 weeks of diabetes induction the blood was collected by cardiac puncture to evaluate glycaemia and glycated haemoglobin. Next the animals were killed and the jejunum was collected and subjected to whole-mount preparation to evidence the myenteric neurons through the histochemical technique of the NADH-diaphorase. The neuronal counts were made in 80 microscopic fields, in tissue samples of five animals of each group. The profiles of the cell bodies of 1000 neurons per group were analysed. Diabetes induced a significant increase in the area of the cell body and decrease in the number of NADH-diaphorase positive myoenteric neurons. ALC suplementation to the diabetic group promoted smaller hypertrophic effects and less neuronal loss than in the myoenteric neurons of the diabetic rats, and in addition diminished the body weight decrease and reduced the fasting glycaemia.
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Affiliation(s)
- M H De Miranda Neto
- Department of Morphophysiological Sciences, Universidade Estadual de Maringá, Campus Regional de Goioerê, Av. Reitor Zeferino Vaz s/n. Jardim Universitário. 87.360-000, Goioere, Brazil
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23
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Abstract
Diabetes mellitus is a heterogeneous group of diseases characterized by high blood glucose levels due to defects in insulin secretion, insulin action, or both. With the number of cases expected to increase rapidly in the years to come, diabetes is a growing health challenge worldwide. Of the approximately 16 million diabetics in the United States, about 1.5 million suffer from type 1 diabetes. In this catabolic disorder afflicting predominantly young individuals, blood insulin is almost completely absent, leading to hyperglycemia and alterations in lipid metabolism. Type 1 diabetes is thought to be induced by a toxic or infectious insult that occurs in genetically predisposed individuals. With recent advances in the understanding of the involved immunology and cellular and molecular mechanisms, researchers strive to battle the disease with new preventive and corrective strategies.
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Affiliation(s)
- Larissa Eiselein
- Molecular, Cellular and Integrative Physiology Graduate Group, University of California, Davis, CA, USA
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24
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Prabhu KS, Arner RJ, Vunta H, Reddy CC. Up-regulation of Human myo-Inositol Oxygenase by Hyperosmotic Stress in Renal Proximal Tubular Epithelial Cells. J Biol Chem 2005; 280:19895-901. [PMID: 15778219 DOI: 10.1074/jbc.m502621200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
myo-Inositol oxygenase (MIOX) catalyzes the oxidative cleavage of myo-inositol (MI) to give d-glucuronic acid, a committed step in MI catabolism. d-Glucuronic acid is further metabolized to xylitol via the glucuronate-xylulose pathway. Although accumulation of polyols such as xylitol and sorbitol is associated with MI depletion in diabetic complications, no causal relationship has been established. Therefore we are examining the role of MIOX in diabetic nephropathy. Here we present evidence that the basis for the depletion of MI in diabetes is likely to be mediated by the increased expression of MIOX, which is induced by sorbitol, mannitol, and xylitol in a porcine renal proximal tubular epithelial cell line, LLC-PK1. To understand the molecular mechanism of regulation of MIOX expression by polyols, we have cloned the human MIOX gene locus of 10 kb containing 5.6 kb of the 5' upstream sequence. Analysis of the 5' upstream sequence led to the identification of an osmotic response element (ORE) in the promoter region, which is present approximately 2 kb upstream of the translation start site. Based on luciferase reporter and electrophoretic mobility shift assays, polyols increased the ORE-dependent expression of MIOX. In addition, we demonstrate that the activity of the promoter is dependent on the binding of the transcription factor, tonicity element-binding protein, or osmotic response element-binding protein, to the ORE site. These results suggest that the expression of MIOX is up-regulated by a positive feedback mechanism where xylitol, one of the products of MI catabolism via the glucuronate-xylulose pathway, induces an overexpression of MIOX.
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Affiliation(s)
- K Sandeep Prabhu
- Department of Veterinary Science, the Pennsylvania State University, University Park, 16802, USA
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25
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Schrijvers BF, De Vriese AS, Flyvbjerg A. From hyperglycemia to diabetic kidney disease: the role of metabolic, hemodynamic, intracellular factors and growth factors/cytokines. Endocr Rev 2004; 25:971-1010. [PMID: 15583025 DOI: 10.1210/er.2003-0018] [Citation(s) in RCA: 242] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
At present, diabetic kidney disease affects about 15-25% of type 1 and 30-40% of type 2 diabetic patients. Several decades of extensive research has elucidated various pathways to be implicated in the development of diabetic kidney disease. This review focuses on the metabolic factors beyond blood glucose that are involved in the pathogenesis of diabetic kidney disease, i.e., advanced glycation end-products and the aldose reductase system. Furthermore, the contribution of hemodynamic factors, the renin-angiotensin system, the endothelin system, and the nitric oxide system, as well as the prominent role of the intracellular signaling molecule protein kinase C are discussed. Finally, the respective roles of TGF-beta, GH and IGFs, vascular endothelial growth factor, and platelet-derived growth factor are covered. The complex interplay between these different pathways will be highlighted. A brief introduction to each system and description of its expression in the normal kidney is followed by in vitro, experimental, and clinical evidence addressing the role of the system in diabetic kidney disease. Finally, well-known and potential therapeutic strategies targeting each system are discussed, ending with an overall conclusion.
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Affiliation(s)
- Bieke F Schrijvers
- Medical Department M/Medical Research Laboratories, Clinical Institute, Aarhus University Hospital, Nørrebrogade 44, DK-8000 Aarhus C, Denmark
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26
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Chistiakov DA, Savost'anov KV, Shestakova MV, Chugunova LA, Samkhalova MS, Dedov II, Nosikov VV. Confirmation of a susceptibility locus for diabetic nephropathy on chromosome 3q23-q24 by association study in Russian type 1 diabetic patients. Diabetes Res Clin Pract 2004; 66:79-86. [PMID: 15364165 DOI: 10.1016/j.diabres.2004.02.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2003] [Revised: 02/10/2004] [Accepted: 02/18/2004] [Indexed: 10/26/2022]
Abstract
Family-based studies and segregation analyses suggest that inherited factors play a significant role in susceptibility to diabetic nephropathy (DN). Moczulski et al. [Diabetes 47 (1998) 1164-1169] found a susceptibility locus for DN in type 1 diabetes covering a 20cM region on chromosome 3q, with a peak of linkage close to the angiotensin II type 1 receptor (AT1) gene. We examined eight polymorphic markers (D3S1512, D3S1550, D3S1557, D3S1744, D3S2326, D3S3599, D3S3694, and a (CA)(n) dinucleotide repeat polymorphism in the 3' flanking region of the AT1 gene) spanning about 6.2 megabases (Mb) in the region of maximal linkage with DN on chromosome 3q23-q24. The markers were used to genotype a total of 381 Russian type 1 diabetic subjects, 195 of whom had DN and 186 had no clinical nephropathy. Four of the markers tested, D3S1512, D3S1550, D3S2326, and D3S3599, showed an association with DN in type 1 diabetes mellitus. These markers are located within a 1.0Mb interval that starts about 4.4Mb centromeric to the AT1 gene. Thus, our results suggest the existence of the DN susceptibility locus previously described by Moczulski et al. on chromosome 3q.
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Affiliation(s)
- Dimitry A Chistiakov
- Laboratory of Aquatic Ecology, Katholieke Universiteit Leuven, Ch. de Beriotstraat 32, B-3000 Leuven, Belgium.
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27
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Coste TC, Gerbi A, Vague P, Pieroni G, Raccah D. Neuroprotective effect of docosahexaenoic acid-enriched phospholipids in experimental diabetic neuropathy. Diabetes 2003; 52:2578-85. [PMID: 14514643 DOI: 10.2337/diabetes.52.10.2578] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A deficiency in essential fatty acid metabolism has been widely reported in both human and animal diabetes. Fish oil supplementations (n-3 fatty acids), containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), were less effective on diabetic neuropathy than (n-6) fatty acids. This partial effect of (n-3) fatty acids might be attributed to the presence of EPA, a competitor of arachidonic acid, which enhanced the diabetes-induced decrease of this fatty acid in serum and tissues. For determining whether a supplementation with DHA alone could prevent neuropathy in streptozotocin-induced diabetes, diabetic rats were given daily, by gavage, liposomes containing DHA phospholipids, at a dose of 60 mg/kg. Eight weeks of diabetes induced significant decreases in nerve conduction velocity (NCV), nerve blood flow (NBF), and sciatic nerve and erythrocyte (red blood cells [RBCs]) Na,K-ATPase activities. DHA phospholipids totally prevented the decrease in NCV and NBF observed during diabetes when compared with the nonsupplemented diabetic group. DHA phospholipids also prevented the Na,K-ATPase activity decrease in RBC but not in sciatic nerve. Moreover, DHA level in sciatic nerve membranes was correlated with NCV. These results demonstrate a protective effect of daily doses of DHA on experimental diabetic neuropathy. Thus, treatment with DHA phospholipids could be suitable for evaluation in clinical trials.
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Affiliation(s)
- Thierry C Coste
- UPRES EA 2193, Faculte de Medecine Timone, Marseille, France.
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28
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Arezzo JC, Zotova E. Electrophysiologic measures of diabetic neuropathy: mechanism and meaning. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2003; 50:229-55. [PMID: 12198812 DOI: 10.1016/s0074-7742(02)50079-9] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Whole nerve electrophysiologic procedures afford a battery of measures that can provide a noninvasive and objective index of the onset and progression of diabetic polyneuropathy (DPN). Advances in physiologic procedures, digital hardware, and mathematical models have allowed assessment of activity in slower conducting fibers, as well as measures that reflect changes in refractory periods and threshold excitability. These expanded options can augment standard measures of maximal conduction velocity and compound amplitude and greatly enhance the sensitivity of whole nerve measure to both structural (e.g. demyelination) and "nonstructural" (e.g. redistribution of ion channels) deficits associated with DPN. The mechanisms underlying the physiologic events in DPN are multifactorial and their sequence in complex, with different mechanisms contributing to change at overlapping, but distinct points in the progression. Factors influencing early change in velocity may differ from those contributing to chronic deficits and these mechanisms may also differ in their response to various putative therapies. This review attempts to summarize the pattern of whole nerve electrophysiologic change associated with DPN, outlines the strengths and limitations of the various measures that are feasible, and discusses the specific impact of know pathophysiologic mechanisms on these end points.
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Affiliation(s)
- Joseph C Arezzo
- Albert Einstein College of Medicine, Bronx, New York 10461, USA
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29
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Obrosova IG. How does glucose generate oxidative stress in peripheral nerve? INTERNATIONAL REVIEW OF NEUROBIOLOGY 2003; 50:3-35. [PMID: 12198815 DOI: 10.1016/s0074-7742(02)50071-4] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Diabetes-associated oxidative stress is clearly manifest in peripheral nerve, dorsal root, and sympathetic ganglia of the peripheral nervous system and endothelial cells and is implicated in nerve blood flow and conduction deficits, impaired neurotrophic support, changes in signal transduction and metabolism, and morphological abnormalities characteristic of peripheral diabetic neuropathy (diabetic peripheral neuropathy). Hyperglycemia has a key role in oxidative stress in diabetic nerve, whereas the contribution of other factors, such as endoneurial hypoxia, transition metal imbalance, and hyperlipidemia, has not been rigorously proven. It has been suggested that oxidative stress, particularly mitochondrial superoxide production, is responsible for sorbitol pathway hyperactivity, nonenzymatic glycation/glycooxidation, and activation of protein kinase C. However, this concept is not supported by in vivo studies demonstrating the lack of any inhibition of the sorbitol pathway activity in peripheral nerve, retina, and lens by antioxidants, including potent superoxide scavengers. Its has been also hypothesized that aldose reductase (AR) detoxifies lipid peroxidation products, and therefore, the enzyme inhibition in diabetes is detrimental rather than benefical. However, the role for AR in lipid peroxdation product metabolism has never been demonstrated in vivo, and the effects of aldose reductase inhibitors and antioxidants on diabetic peripheral neuropathy are unidirectional, i.e., both classes of agents prevent and correct functional, metabolic, neurotrophic, and morphological changes in diabetic nerve. Growing evidence indicates that AR has a key role in oxidative stress in the peripheral nerve and contributes to superoxide production by the vascular endothelium. The potential mechanisms of this phenonmenon are discussed.
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Affiliation(s)
- Irina G Obrosova
- Department of Internal Medicine, Division of Endocrinology and Metabolism, University of Michigan Medical Center, Ann Arbor, Michigan 48109, USA
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Obrosova IG, Van Huysen C, Fathallah L, Cao XC, Greene DA, Stevens MJ. An aldose reductase inhibitor reverses early diabetes-induced changes in peripheral nerve function, metabolism, and antioxidative defense. FASEB J 2002; 16:123-5. [PMID: 11709499 DOI: 10.1096/fj.01-0603fje] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Aldose reductase inhibitors (ARIs) prevent peripheral nerve dysfunction and morphological abnormalities in diabetic animal models. However, some experimental intervention studies and clinical trials of ARIs on diabetic neuropathy appeared disappointing because of either 1) their inadequate design and, in particular, insufficient correction of the sorbitol pathway activity or 2) the inability to reverse established functional and metabolic deficits of diabetic neuropathy by AR inhibition in general. We evaluated whether diabetes-induced changes in nerve function, metabolism, and antioxidative defense are corrected by the dose of ARI (sorbinil, 65 mg/kg/d in the diet), resulting in complete inhibition of increased sorbitol pathway activity. The groups included control rats and streptozotocin-diabetic rats treated with/without ARI for 2 weeks after 4 weeks of untreated diabetes. ARI treatment corrected diabetes-induced nerve functional changes; that is, decrease in endoneurial nutritive blood flow, motor and sensory nerve conduction velocities, and metabolic abnormalities (i.e., mitochondrial and cytosolic NAD+/NADH redox imbalances and energy deficiency). ARI restored nerve concentrations of two major non-enzymatic antioxidants, reduced glutathione (GSH) and ascorbate, and completely arrested diabetes-induced lipid peroxidation. In conclusion, treatment with adequate doses of ARIs (that is, doses that completely inhibit increased sorbitol pathway activity) is an effective approach for reversal of, at least, early diabetic neuropathy.
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Affiliation(s)
- Irina G Obrosova
- Division of Endocrinology and Metabolism, Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0354, USA.
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31
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Arner RJ, Prabhu KS, Thompson JT, Hildenbrandt GR, Liken AD, Reddy CC. myo-Inositol oxygenase: molecular cloning and expression of a unique enzyme that oxidizes myo-inositol and D-chiro-inositol. Biochem J 2001; 360:313-20. [PMID: 11716759 PMCID: PMC1222231 DOI: 10.1042/0264-6021:3600313] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
myo-Inositol oxygenase (MIOX) catalyses the first committed step in the only pathway of myo-inositol catabolism, which occurs predominantly in the kidney. The enzyme is a non-haem-iron enzyme that catalyses the ring cleavage of myo-inositol with the incorporation of a single atom of oxygen. A full-length cDNA was isolated from a pig kidney library with an open reading frame of 849 bp and a corresponding protein subunit molecular mass of 32.7 kDa. The cDNA was expressed in a bacterial pET expression system and an active recombinant MIOX was purified from bacterial lysates to electrophoretic homogeneity. The purified enzyme displayed the same catalytic properties as the native enzyme with K(m) and k(cat) values of 5.9 mM and 11 min(-1) respectively. The pI was estimated to be 4.5. Preincubation with 1 mM Fe(2+) and 2 mM cysteine was essential for the enzyme's activity. D-chiro-Inositol, a myo-inositol isomer, is a substrate for the recombinant MIOX with an estimated K(m) of 33.5 mM. Both myo-inositol and D-chiro-inositol have been implicated in the pathogenesis of diabetes. Thus an understanding of the regulation of MIOX expression clearly represents a potential window on the aetiology of diabetes as well as on the control of various intracellular phosphoinositides and key signalling pathways.
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Affiliation(s)
- R J Arner
- Department of Veterinary Science and Center for Molecular Toxicology and Carcinogenesis, 115 Henning Building, The Pennsylvania State University, University Park, PA 16802, USA
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32
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Tsimaratos M, Coste TC, Djemli-Shipkolye A, Vague P, Pieroni G, Raccah D. Gamma-linolenic acid restores renal medullary thick ascending limb Na(+),K(+)-ATPase activity in diabetic rats. J Nutr 2001; 131:3160-5. [PMID: 11739860 DOI: 10.1093/jn/131.12.3160] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In diabetes, the activity of Delta-6 desaturase, which converts linoleic acid (LA) into gamma-linolenic acid (GLA), the first step of arachidonic acid (AA) synthesis, is decreased, leading to alterations in membrane phospholipid composition. On the other hand, 12 wk after the onset of diabetes, Na(+),K(+)-ATPase activity is reduced in many organs, including the kidney. The medullary thick ascending limb (MTAL) reduced Na(+),K(+)-ATPase activity, whereas the sodium load secondary to glomerular hyperfiltration was increased. The aim of our study was to examine whether the changes in membrane fatty acid composition resulting from the inhibition of Delta-6 desaturase may be involved in the decreased Na(+),K(+)-ATPase activity observed in the outer MTAL after 12 wk of diabetes. GLA is a fatty acid that by-passes the Delta-6 desaturase step. We measured the membrane fatty acid composition and the Na(+),K(+)-ATPase activity in the renal outer medulla of control and streptozotocin (STZ)-induced diabetic rats 12 wk after the induction of diabetes. Measurements were performed after supplementation of control rats with sunflower oil (SO) or GLA for 12 wk, and supplementation of 12 wk diabetic rats with SO for 12 wk or with GLA for 6 or 12 wk. Supplementation with GLA not only prevented the decrease in Na(+),K(+)-ATPase activity observed after 12 wk of diabetes but also time dependently stimulated Na(+),K(+)-ATPase activity in the outer medulla. The changes in Na(+),K(+)-ATPase activity were related to parallel changes in the amount of Na(+),K(+)-ATPase alpha(1) subunit protein. In addition, in diabetic rats only, Na(+),K(+)-ATPase activity was positively correlated with the amount of AA present in cell membranes (r = 0.92, P < 0.05). Our results indicate that nutritional GLA supplementation increases Na(+),K(+)-ATPase activity and expression in diabetic rats. In addition, the positive correlation between AA content and Na(+),K(+)-ATPase activity suggests that in diabetic rats, alterations in membrane fatty acid composition contribute to the decreased Na(+),K(+)-ATPase activity in outer medulla.
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Affiliation(s)
- M Tsimaratos
- UPRES EA 21-93, Faculté de Médecine Timone, 13385 Marseille cedex 05, France.
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Aragno M, Parola S, Brignardello E, Manti R, Betteto S, Tamagno E, Danni O, Boccuzzi G. Oxidative stress and eicosanoids in the kidneys of hyperglycemic rats treated with dehydroepiandrosterone. Free Radic Biol Med 2001; 31:935-42. [PMID: 11595378 DOI: 10.1016/s0891-5849(01)00669-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxidative stress plays a crucial role in the pathogenesis of chronic diabetic complications. Normoglycemic and streptozotocin-diabetic rats were treated with dehydroepiandrosterone (DHEA) (4 mg/d per rat) for 3 weeks. At the end of treatment, hydroxynonenal, hydroperoxyeicosatetraenoic acids and antioxidant levels, as well as Na/K-ATPase activity and membrane fatty acids composition were evaluated in kidney homogenates. Chronic hyperglycemia caused a marked increase of both hydroxynonenal and lipoxygenase pathway products and a drop in both GSH levels and membrane Na/K-ATPase activity. DHEA treatment restored the antioxidant levels to close to the control value and considerably reduced hydroxynonenal and hydroperoxyeicosatetraenoic acid levels. Moreover, DHEA counteracted the detrimental effect of hyperglycemia on membrane function: the drop of Na/K-ATPase activity in diabetic animals was significantly inhibited by DHEA treatment. These results show that DHEA reduces oxidative stress and the consequent increase of lipoxygenase pathway products induced by experimental diabetes in rat kidney; they also suggest that, by reducing the inflammatory response to oxidative stress, DHEA treatment might delay the progression of diabetic kidney disease.
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Affiliation(s)
- M Aragno
- Department of Experimental Medicine and Oncology, General Pathology Section, University of Turin, Turin, Italy
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Kihara M, Mitsui Y, Shioyama M, Hasegawa T, Takahashi M, Takakura S, Minoura K, Kawamura I. Effect of zenarestat, an aldose reductase inhibitor, on endoneurial blood flow in experimental diabetic neuropathy of rat. Neurosci Lett 2001; 310:81-4. [PMID: 11585572 DOI: 10.1016/s0304-3940(01)02052-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The effects of zenarestat, an aldose reductase inhibitor, on endoneurial blood flow (NBF) were explored in streptozotocin-induced diabetic rats. Rats were maintained on a diet of containing 0.09% zenarestat for 8 weeks, then NBF in the sciatic nerve was measured using microelectrode hydrogen polarography. NBF in the diabetic control rats was significantly lower than values in age-matched control rats, however, NBF was not significantly altered in diabetic rats treated with zenarestat. Direct application of nitric oxide synthase inhibitor, NG-nitro-L-arginine, did not affect NBF in diabetic control rats, whereas this application significantly reduced NBF both in age-matched control and zenarestat treated diabetic rats. Considerable levels of zenarestat were confirmed in the sciatic nerve in the drug treated rats. These data suggest that aldose reductase, such as zenarestat, might restore or prevent the alteration of endoneurial blood flow resulting from an impairment of nitric oxide function.
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Affiliation(s)
- M Kihara
- Department of Neurology, Kinki University, School of Medicine, Ohno-Higashi, Osaka-Sayama, Osaka 589, Japan
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Lee SC, Wang Y, Ko GT, Critchley JA, Ng MC, Tong PC, Cockram CS, Chan JC. Association of retinopathy with a microsatellite at 5' end of the aldose reductase gene in Chinese patients with late-onset Type 2 diabetes. Ophthalmic Genet 2001; 22:63-7. [PMID: 11449315 DOI: 10.1076/opge.22.2.63.2230] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Recent experimental data suggest that a microsatellite polymorphism at 5' end of the aldose reductase gene may be associated with the development of diabetic retinopathy. In the present study, we examined the allele distribution of the polymorphism in 384 Hong Kong Chinese patients who had late-onset (age at diagnosis > or =35 years) Type 2 diabetes, but no clinical evidence of cataract. Approximately 17% of them (n = 64) had retinopathy. The patients with retinopathy were older (52 +/- 11 years vs. 60 +/- 9 years, p < 0.01) and had a higher HbA1c (8.9 +/- 2.2% vs. 7.7 +/- 2.0%, p < 0.01 with adjustment for age) than those without the complication. Amongst all of the patients, we detected 10 microsatellite alleles and found that allele Z-4 was overpresented in those with retinopathy (9% vs. 4%, p < 0.05). There were no significant differences in allelic distributions of the major alleles Z + 2, Z, and Z-2, which accounted for more than 80% of the overall frequency, between the two groups of patients. Using multiple logistic regression analysis (R2 = 0.17, p < 0.01), we found that age (p < 0.01) and HbA1c (p < 0.05) were associated with retinopathy. In conclusion, our data suggest that the occurrence of diabetic retinopathy in the Chinese population may be influenced by clinical and metabolic factors. The aldose reductase gene may be implicated, but is not likely to play a major role.
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Affiliation(s)
- S C Lee
- Department of Medicine and Therapeutics, The Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
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Shimoshige Y, Ikuma K, Yamamoto T, Takakura S, Kawamura I, Seki J, Mutoh S, Goto T. The effects of zenarestat, an aldose reductase inhibitor, on peripheral neuropathy in Zucker diabetic fatty rats. Metabolism 2000; 49:1395-9. [PMID: 11092500 DOI: 10.1053/meta.2000.17723] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We studied the effects of zenarestat, an aldose reductase inhibitor (ARI), on peripheral neuropathy in Zucker diabetic fatty (ZDF) rats, an animal model of type 2 diabetes. ZDF rats and their lean rats counterparts were fed a sucrose-containing diet, and zenarestat was given orally once a day for 8 weeks. Motor nerve conduction velocity (MNCV), F-wave minimal latency (FML), and sorbitol concentrations in the sciatic nerve were measured. In ZDF control rats, a remarkable accumulation of sorbitol, a delay in FML, and a slowing of MNCV were observed compared with lean rats. At a dose of 3.2 mg/kg, zenarestat had no significant effect on the delay in FML and the slowing of MNCV, although the sorbitol accumulation in the sciatic nerve was partially inhibited in ZDF rats. On the other hand, 32 mg/kg zenarestat treatment improved these nerve dysfunctions in ZDF rats, along with a reduction of nerve sorbitol accumulation almost to the level of lean rats. These data showed that zenarestat improved diabetic peripheral neuropathy in ZDF rats, a type 2 diabetes model, providing evidence for the therapeutic potential of zenarestat for the treatment of diabetic neuropathy.
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Affiliation(s)
- Y Shimoshige
- Department of Metabolic Diseases, Fujisawa Pharmaceutical, Osaka, Japan
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Sellers DJ, Chess-Williams R. The effect of sorbinil, an aldose reductase inhibitor, on aortic function in control and streptozotocin-induced diabetic rats. JOURNAL OF AUTONOMIC PHARMACOLOGY 2000; 20:15-22. [PMID: 11048957 DOI: 10.1046/j.1365-2680.2000.00155.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. The present study investigates the effect of treatment of 14-day streptozotocin-diabetic rats with the aldose reductase inhibitor, sorbinil, on changes ex vivo in aortic vasoconstriction and vasodilation. 2. Maximum contractile responses and aortic sensitivity to phenylephrine were significantly enhanced in aortae from 14-day diabetic rats, in accordance with our previous data. 3. Endothelium-dependent relaxations to carbachol were, in contrast, depressed, although endothelium-independent relaxations to forskolin and sodium nitroprusside were unaltered. 4. Sorbinil treatment of diabetic animals failed to prevent any of these diabetes-induced alterations in aortic function, and indeed exacerbated some of these alterations. In addition, sorbinil treatment caused altered aortic responses in control animals, which sometimes mirrored those found in diabetic animals. 5. It can be concluded that sorbinil may have actions in addition to, and independent of, polyol pathway inhibition. Thus, sorbinil may not be an effective tool for the investigation of aldose reductase inhibition within the vascular system of the rat.
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Affiliation(s)
- D J Sellers
- Department of Biomedical Science, University of Sheffield, Western Bank, UK
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