Background: Obesity and type 2 diabetes are major risk factors for peripheral arterial disease in humans, which can result in lower limb demand ischemia and exercise intolerance. Exercise triggers skeletal muscle adaptation including increased vasculogenesis. The goal of this study was to determine whether demand ischemia modulates revascularization, fiber size, and signaling pathways in the ischemic hind limb muscles of mice with diet-induced obesity (DIO).
Materials And Methods: DIO mice (n = 7) underwent unilateral femoral artery ligation and recovered for 2 wks followed by 4 wks with daily treadmill exercise to induce demand ischemia. A parallel sedentary ischemia (SI) group (n = 7) had femoral artery ligation without exercise. The contralateral limb muscles of SI served as control. Muscles were examined for capillary density, myofiber cross-sectional area, cytokine levels, and phosphorylation of STAT3 and ERK1/2.
Results: Exercise significantly enhanced capillary density (P < 0.01) and markedly lowered cross-sectional area (P < 0.001) in demand ischemia compared with SI. These findings coincided with a significant increase in granulocyte colony-stimulating factor (P < 0.001) and interleukin-7 (P < 0.01) levels. In addition, phosphorylation levels of STAT3 and ERK1/2 (P < 0.01) were increased, whereas UCP1 and monocyte chemoattractant protein-1 protein levels were lower (P < 0.05) without altering vascular endothelial growth factor and tumor necrosis factor alpha protein levels. Demand ischemia increased the PGC1α messenger RNA (P < 0.001) without augmenting PGC1α protein levels.
Conclusions: Exercise-induced limb demand ischemia in the setting of DIO causes myofiber atrophy despite an increase in muscle capillary density. The combination of persistent increase in tumor necrosis factor alpha, lower vascular endothelial growth factor, and failure to increase PGC1α protein may reflect a deficient adaption to demand ischemia in DIO.
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http://dx.doi.org/10.1016/j.jss.2016.06.001 | DOI Listing |
J Neurotrauma
December 2024
Department of Medical Sciences, Section of Neurosurgery, Uppsala University, Uppsala, Sweden.
This study compared the roles of extraparenchymal autonomic nervous system (ANS) control of cerebral blood flow (CBF) versus intraparenchymal cerebrovascular autoregulation in 487 patients with aneurysmal subarachnoid hemorrhage (SAH) and 413 patients with traumatic brain injury (TBI). Vasomotion intensity of extraparenchymal and intraparenchymal vessels were quantified as the amplitude of oscillations of arterial blood pressure (ABP) and intracranial pressure (ICP) in the very low frequency range of 0.02-0.
View Article and Find Full Text PDFASAIO J
December 2024
Division of Cardiac Surgery, Department of Surgery, University of Alberta, Edmonton, Alberta, Canada.
Donor heart machine perfusion enables avoidance of prolonged cold ischemia, however the optimal temperature is yet to be elucidated. Given that maintenance of temperature beyond ambient levels demands significant energy, we sought to determine the suitability of room-temperature perfusion preservation of neonatal/pediatric-sized (5-20 kg) piglet donor hearts. A custom device was fabricated suitable for this purpose, with continuous readout of perfusion pressure, flow rate, temperature, and oxygen saturation.
View Article and Find Full Text PDFBMC Nephrol
December 2024
Kidney Disease and Transplant Center, Shonan Kamakura General Hospital, 1370-1 Okamoto, Kamakura, 247-8533, Kanagawa, Japan.
Background: Recently, the incidence of caffeine intoxication has been on an upward trend, with severe outcomes. However, acute kidney injury (AKI) resulting from renal pathologies secondary to caffeine intoxication is rare, and the pathophysiological mechanisms underlying AKI are unclear.
Case Presentation: A female patient in her 20s ingested an over-the-counter drug containing caffeine.
Future Cardiol
December 2024
Department of Physiology, Institute of Postgraduate Medical Education & Research-SSKM Hospital, Kolkata, India.
Aims: To objectively characterize the spatial-velocity dynamics of the QRS-loop in the vectorcardiogram (VCG) of patients with acute myocardial infarction (AMI).
Methods: VCG was constructed as a space curve directly with three quasi-orthogonal leads I, aVF and V2 recorded by conventional ECG of 25 healthy individuals and 50 AMI patients. Spatial velocity (SV) of the dynamic QRS loop, spatial distance (SD), and spatial magnitude (SM) were recorded, along with axis-specific component attributes of vector magnitude such as ΔX, ΔY, and ΔZ.
JTCVS Tech
December 2024
Section of Pediatric Cardiac Surgery, Children's Hospital Colorado and University of Colorado School of Medicine, Aurora, Colo.
Objective: Prior studies suggest that prolonged donor heart warm ischemia time increases heart transplant mortality. Patients with single-ventricle heart disease requiring transplant with concomitant aortic arch or central pulmonary artery reconstruction present technical challenges that extend donor warm ischemia time using conventional techniques. Studies in larger pediatric and adult patients with single-ventricle anatomy have described the use of prosthetic material for concomitant great vessel reconstruction.
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