Mitochondrial respiratory chain dysfunction in dorsal root ganglia of streptozotocin-induced diabetic rats and its correction by insulin treatment
| Autor: | Eli Akude, Paul Fernyhough, Corinne G. Jolivalt, Sharmila Chattopadhyay, Elena Zherebitskaya, Nigel A. Calcutt, Subir K. Roy Chowdhury, Darrell R. Smith |
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| Rok vydání: | 2010 |
| Předmět: |
Male
medicine.medical_specialty Complications Endocrinology Diabetes and Metabolism medicine.medical_treatment Citrate (si)-Synthase Mitochondrion Diabetes Mellitus Experimental Rats Sprague-Dawley 03 medical and health sciences 0302 clinical medicine Oxygen Consumption Downregulation and upregulation Diabetic Neuropathies Diabetes mellitus Internal medicine Ganglia Spinal Internal Medicine medicine Citrate synthase Animals Hypoglycemic Agents Insulin Respiratory function 030304 developmental biology 0303 health sciences biology medicine.disease Streptozotocin Mitochondria Rats Endocrinology Mitochondrial respiratory chain biology.protein Original Article Reactive Oxygen Species 030217 neurology & neurosurgery medicine.drug |
| Zdroj: | Diabetes |
| ISSN: | 1939-327X |
| Popis: | OBJECTIVE Impairments in mitochondrial physiology may play a role in diabetic sensory neuropathy. We tested the hypothesis that mitochondrial dysfunction in sensory neurons is due to abnormal mitochondrial respiratory function. RESEARCH DESIGN AND METHODS Rates of oxygen consumption were measured in mitochondria from dorsal root ganglia (DRG) of 12- to- 22-week streptozotocin (STZ)-induced diabetic rats, diabetic rats treated with insulin, and age-matched controls. Activities and expression of components of mitochondrial complexes and reactive oxygen species (ROS) were analyzed. RESULTS Rates of coupled respiration with pyruvate + malate (P + M) and with ascorbate + TMPD (Asc + TMPD) in DRG were unchanged after 12 weeks of diabetes. By 22 weeks of diabetes, respiration with P + M was significantly decreased by 31–44% and with Asc + TMPD by 29–39% compared with control. Attenuated mitochondrial respiratory activity of STZ-diabetic rats was significantly improved by insulin that did not correct other indices of diabetes. Activities of mitochondrial complexes I and IV and the Krebs cycle enzyme, citrate synthase, were decreased in mitochondria from DRG of 22-week STZ-diabetic rats compared with control. ROS levels in perikarya of DRG neurons were not altered by diabetes, but ROS generation from mitochondria treated with antimycin A was diminished compared with control. Reduced mitochondrial respiratory function was associated with downregulation of expression of mitochondrial proteins. CONCLUSIONS Mitochondrial dysfunction in sensory neurons from type 1 diabetic rats is associated with impaired rates of respiratory activity and occurs without a significant rise in perikaryal ROS. |
| Databáze: | OpenAIRE |
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