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McDonald MW, Olver TD, Dotzert MS, Jurrissen TJ, Noble EG, Padilla J, Melling CJ. Aerobic exercise training improves insulin-induced vasorelaxation in a vessel-specific manner in rats with insulin-treated experimental diabetes. Diab Vasc Dis Res 2019; 16:77-86. [PMID: 30537862 DOI: 10.1177/1479164118815279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Vascular insulin resistance often precedes endothelial dysfunction in type 1 diabetes mellitus. Strategies to limit vascular dysfunction include intensive insulin therapy (4-9 mM) and aerobic training. To avoid the risk of hypoglycaemia, individuals often prescribed conventional insulin therapy (9-15 mM) and participate in resistance training. In a model of type 1 diabetes mellitus, this study examined insulin-induced vasomotor function in the aorta and femoral artery to determine (1) whether resistance training with conventional insulin therapy provides the same benefits as aerobic training with conventional insulin therapy, (2) whether aerobic training or resistance training, when paired with conventional insulin therapy, results in superior vasomotor function compared to intensive insulin therapy alone and (3) whether vessel-specific adaptations exist. Groups consisted of conventional insulin therapy, intensive insulin therapy, aerobic training with conventional insulin therapy and resistance training with conventional insulin therapy. Following multiple low doses of streptozotocin, male Sprague-Dawley rats were supplemented with insulin to maintain blood glucose concentrations (9-15 mM: conventional insulin therapy, aerobic training and resistance training; 4-9 mM: intensive insulin therapy) for 12 weeks. Aerobic training performed treadmill exercise and resistance training consisted of weighted climbing. Coinciding with increased Akt signalling, aerobic training resulted in enhanced insulin-induced vasorelaxation in the femoral artery. Intensive insulin therapy displayed increased mitogen-activated protein kinase signalling and no improvement in insulin-stimulated vasorelaxation compared to all other groups. These data suggest that aerobic training may be more beneficial for limiting the pathogenesis of vascular disease in type 1 diabetes mellitus than merely intensive insulin therapy.
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Affiliation(s)
- Matthew W McDonald
- 1 School of Kinesiology, Western University, London, ON, Canada
- 2 Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - T Dylan Olver
- 3 Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | | | - Thomas J Jurrissen
- 4 Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA
| | - Earl G Noble
- 1 School of Kinesiology, Western University, London, ON, Canada
- 5 Lawson Health Research Institute, London, ON, Canada
| | - Jaume Padilla
- 4 Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA
- 6 Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
- 7 Department of Child Health, University of Missouri, Columbia, MO, USA
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Olver TD, Grisé KN, McDonald MW, Dey A, Allen MD, Rice CL, Lacefield JC, Melling CJ, Noble EG, Shoemaker JK. The relationship between blood pressure and sciatic nerve blood flow velocity in rats with insulin-treated experimental diabetes. Diab Vasc Dis Res 2014; 11:281-289. [PMID: 24853907 DOI: 10.1177/1479164114533357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Peripheral nerve blood flow (NBF) does not autoregulate but, instead, responds passively to changes in mean arterial pressure (MAP). How this relationship is impacted by insulin-treated experimental diabetes (ITED) is unknown. We tested the hypothesis that ITED will reduce NBF across a range of MAP in Sprague Dawley rats. Following 10 weeks of control or ITED conditions, conscious MAP (tail-cuff) was measured, and under anaesthesia, the MAP (carotid artery catheter, pressure transducer) and NBF (Doppler ultrasound, 40 MHz) responses to sodium nitroprusside (60 µg/kg) and phenylephrine (12 µg/kg) infusion were recorded (regression equations for MAP vs NBF were created for each rodent). Thereafter, motor nerve conduction velocity (MNCV) and nerve vascularization (haematoxylin and eosin stain) were determined. Conscious MAP was higher and MNCV was lower in the ITED group (p < 0.01). In response to drug infusions, the ΔMAP and ΔNBF were similar between groups (p ≥ 0.18). Estimated conscious NBF (based on substituting conscious MAP values into each individual regression equation) was greater in the ITED group (p < 0.01). Sciatic nerve vascularization was similar between groups (p ≥ 0.50). In contrast to the hypothesis, NBF was not reduced across a range of MAP. In spite of increased estimated conscious NBF values, MNCV was reduced in rats with ITED.
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Affiliation(s)
- T Dylan Olver
- Neurovascular Research Laboratory, School of Kinesiology, Western University, London, ON, Canada
| | - Kenneth N Grisé
- Exercise Biochemistry Laboratory, School of Kinesiology, Western University, London, ON, Canada
| | - Matthew W McDonald
- Exercise Biochemistry Laboratory, School of Kinesiology, Western University, London, ON, Canada
| | - Adwitia Dey
- Exercise Biochemistry Laboratory, School of Kinesiology, Western University, London, ON, Canada
| | - Matti D Allen
- Neuromuscular Research Laboratory, School of Kinesiology, Western University, London, ON, Canada
| | - Charles L Rice
- Neuromuscular Research Laboratory, School of Kinesiology, Western University, London, ON, Canada
| | - James C Lacefield
- Department of Electrical and Computer Engineering, Western University, London, ON, Canada Department of Medical Biophysics, Western University, London, ON, Canada Robarts Research Institute, Western University, London, ON, Canada
| | - Cw James Melling
- Exercise Biochemistry Laboratory, School of Kinesiology, Western University, London, ON, Canada
| | - Earl G Noble
- Exercise Biochemistry Laboratory, School of Kinesiology, Western University, London, ON, Canada
| | - J Kevin Shoemaker
- Neurovascular Research Laboratory, School of Kinesiology, Western University, London, ON, Canada Department of Physiology and Pharmacology, Western University, London, ON, Canada
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