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Keske MA, Barrett EJ, Lindner JR, Richter EA, Liu Z, McConell GK, Askew CD, Serné EH, Premilovac D, Richards SM, Rattigan S, Eringa EC. Perfusion controls muscle glucose uptake by altering the rate of glucose dispersion in vivo. Am J Physiol Endocrinol Metab 2020; 318:E311-E312. [PMID: 32068465 DOI: 10.1152/ajpendo.00430.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Michelle A Keske
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Geelong, Victoria, Australia
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia
| | - Eugene J Barrett
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia
| | | | - Erik A Richter
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Denmark
| | - Zhenqi Liu
- Division of Endocrinology, Department of Medicine, University of Virginia, School of Medicine, Charlottesville, Virginia
| | - Glenn K McConell
- Institute for Health and Sport (IHeS), Victoria University, Melbourne, Victoria, Australia
| | - Christopher D Askew
- VasoActive Research Group, Sunshine Coast Health Institute (SCHI), University of the Sunshine Coast, Birtinya, Queensland, Australia
| | - Erik H Serné
- Department of Internal Medicine, Amsterdam University Medical Center, VU University Medical Centre, Amsterdam, The Netherlands
| | - Dino Premilovac
- School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | | | - Stephen Rattigan
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia
| | - Etto C Eringa
- Department of Physiology, Amsterdam University Medical Center, VU University Medical Centre, Amsterdam, The Netherlands
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2
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Wang G, Tiemeier GL, van den Berg BM, Rabelink TJ. Endothelial Glycocalyx Hyaluronan: Regulation and Role in Prevention of Diabetic Complications. THE AMERICAN JOURNAL OF PATHOLOGY 2020; 190:781-790. [PMID: 32035886 DOI: 10.1016/j.ajpath.2019.07.022] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/13/2019] [Accepted: 07/30/2019] [Indexed: 10/25/2022]
Abstract
The endothelial glycocalyx is critically involved in vascular integrity and homeostasis, by regulating vascular permeability, regulating mechanotransduction, and reducing inflammation and coagulation. The turnover of the glycocalyx is dynamic to fine-tune these processes. This is in particular true for its main structural component, hyaluronan (HA). Degradation and shedding of the glycocalyx by enzymes, such as hyaluronidase 1 and hyaluronidase 2, are responsible for regulation of the glycocalyx thickness and hence access of circulating cells and factors to the endothelial cell membrane and its receptors. This degradation process will at the same time also allow for resynthesis and adaptive chemical modification of the glycocalyx. The (re)synthesis of HA is dependent on the availability of its sugar substrates, thus linking glycocalyx biology directly to cellular glucose metabolism. It is therefore of particular interest to consider the consequences of dysregulated cellular glucose in diabetes for glycocalyx biology and its implications for endothelial function. This review summarizes the metabolic regulation of endothelial glycocalyx HA and its potential as a therapeutic target in diabetic vascular complications.
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Affiliation(s)
- Gangqi Wang
- Division of Nephrology, Department of Internal Medicine, the Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Gesa L Tiemeier
- Division of Nephrology, Department of Internal Medicine, the Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Bernard M van den Berg
- Division of Nephrology, Department of Internal Medicine, the Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Ton J Rabelink
- Division of Nephrology, Department of Internal Medicine, the Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, the Netherlands.
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3
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McClatchey PM, Williams IM, Xu Z, Mignemi NA, Hughey CC, McGuinness OP, Beckman JA, Wasserman DH. Perfusion controls muscle glucose uptake by altering the rate of glucose dispersion in vivo. Am J Physiol Endocrinol Metab 2019; 317:E1022-E1036. [PMID: 31526289 PMCID: PMC6957378 DOI: 10.1152/ajpendo.00260.2019] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
These studies test, using intravital microscopy (IVM), the hypotheses that perfusion effects on insulin-stimulated muscle glucose uptake (MGU) are 1) capillary recruitment independent and 2) mediated through the dispersion of glucose rather than insulin. For experiment 1, capillary perfusion was visualized before and after intravenous insulin. No capillary recruitment was observed. For experiment 2, mice were treated with vasoactive compounds (sodium nitroprusside, hyaluronidase, and lipopolysaccharide), and dispersion of fluorophores approximating insulin size (10-kDa dextran) and glucose (2-NBDG) was measured using IVM. Subsequently, insulin and 2[14C]deoxyglucose were injected and muscle phospho-2[14C]deoxyglucose (2[C14]DG) accumulation was used as an index of MGU. Flow velocity and 2-NBDG dispersion, but not perfused surface area or 10-kDa dextran dispersion, predicted phospho-2[14C]DG accumulation. For experiment 3, microspheres of the same size and number as are used for contrast-enhanced ultrasound (CEU) studies of capillary recruitment were visualized using IVM. Due to their low concentration, microspheres were present in only a small fraction of blood-perfused capillaries. Microsphere-perfused blood volume correlated to flow velocity. These findings suggest that 1) flow velocity rather than capillary recruitment controls microvascular contributions to MGU, 2) glucose dispersion is more predictive of MGU than dispersion of insulin-sized molecules, and 3) CEU measures regional flow velocity rather than capillary recruitment.
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Affiliation(s)
- P Mason McClatchey
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
| | - Ian M Williams
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
| | - Zhengang Xu
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee
| | - Nicholas A Mignemi
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
| | - Curtis C Hughey
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
| | - Owen P McGuinness
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
- Mouse Metabolic Phenotyping Center, Vanderbilt University, Nashville, Tennessee
| | | | - David H Wasserman
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee
- Mouse Metabolic Phenotyping Center, Vanderbilt University, Nashville, Tennessee
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4
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Weissgerber TL, Garcia‐Valencia O, Milic NM, Codsi E, Cubro H, Nath MC, White WM, Nath KA, Garovic VD. Early Onset Preeclampsia Is Associated With Glycocalyx Degradation and Reduced Microvascular Perfusion. J Am Heart Assoc 2019; 8:e010647. [PMID: 30764695 PMCID: PMC6405679 DOI: 10.1161/jaha.118.010647] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 12/12/2018] [Indexed: 12/11/2022]
Abstract
Background The endothelial glycocalyx is a vasoprotective barrier between the blood and endothelium. We hypothesized that glycocalyx degradation is present in preeclampsia, a pregnancy-specific hypertensive disorder characterized by endothelial dysfunction and activation. Methods and Results We examined the sublingual glycocalyx noninvasively using sidestream dark field imaging in the third trimester among women with normotensive pregnancies (n=73), early (n=14) or late (n=29) onset preeclampsia, or gestational diabetes mellitus (n=21). We calculated the width of the glycocalyx that was permeable to red blood cells (called the perfused boundary region, a measure of glycocalyx degradation) and the percentage of vessels that were filled with red blood cells ≥50% of the time (a measure of microvascular perfusion). In addition, we measured circulating levels of glycocalyx components, including heparan sulfate proteoglycans, hyaluronic acid, and SDC1 (syndecan 1), in a subset of participants by ELISA . Repeated-measures ANOVA was performed to adjust for vessel diameter and caffeine intake. Women with early onset preeclampsia showed higher glycocalyx degradation, indicated by a larger perfused boundary region (mean: 2.14 [95% CI, 2.05-2.20]), than the remaining groups (mean: normotensive: 1.99 [95% CI, 1.95-2.02], P=0.002; late-onset preeclampsia: 2.01 [95% CI, 1.96-2.07], P=0.024; gestational diabetes mellitus: 1.97 [95% CI, 1.91-2.04], P=0.004). The percentage of vessels that were filled with red blood cells was significantly lower in early onset preeclampsia. These structural glycocalyx changes were accompanied by elevated plasma concentrations of the glycocalyx components, heparan sulfate proteoglycans and hyaluronic acid, in early onset preeclampsia compared with normotensive pregnancy. Conclusions Glycocalyx degradation and reduced microvascular perfusion are associated with endothelial dysfunction and activation and vascular injury in early onset preeclampsia.
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Affiliation(s)
- Tracey L. Weissgerber
- Division of Nephrology & HypertensionMayo ClinicRochesterMN
- QUEST – Quality | Ethics | Open Science | TranslationCharité ‐ Universitätsmedizin BerlinBerlin Institutes of Health (BIH)BerlinGermany
| | | | - Natasa M. Milic
- Division of Nephrology & HypertensionMayo ClinicRochesterMN
- Department of Medical Statistics & InformaticsMedical FacultyUniversity of BelgradeSerbia
| | - Elizabeth Codsi
- Departement d'Obstetrique‐gynecologieFaculte de MedicineUniversite de MontrealCanada
| | | | | | - Wendy M. White
- Department of Obstetrics and GynecologyMayo ClinicRochesterMN
- Department of PerinatologyOlmsted Medical CenterRochesterMN
| | - Karl A. Nath
- Division of Nephrology & HypertensionMayo ClinicRochesterMN
| | - Vesna D. Garovic
- Division of Nephrology & HypertensionMayo ClinicRochesterMN
- Department of Obstetrics and GynecologyMayo ClinicRochesterMN
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5
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Zhu J, Frech T. Gut disease in systemic sclerosis - new approaches to common problems. CURRENT TREATMENT OPTIONS IN RHEUMATOLOGY 2019; 5:11-19. [PMID: 31750073 DOI: 10.1007/s40674-019-00117-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Purpose of review The goal of this manuscript is to discuss the new diagnostic and potential treatment options for gut disease in systemic sclerosis (SSc). The concepts of quantification of gut perfusion and motility is reviewed. The risks of empiric therapeutics and challenges of studying the microbiome in SSc is discussed. Recent findings There are diagnostics that can provide information on gut perfusion and function that are of value in SSc. Easily implemented diagnostic tests are critical to avoid complications of empiric therapy. The role of the microbiome and drugs that target dysmotility are areas of active research. Summary SSc-related gastrointestinal tract involvement can be heterogeneous in clinical presentation and disease course. Noninvasive gastrointestinal measurement techniques that quantify neural communications with microvasculature in SSc can potentially guide the proper addition and discontinuation of therapeutics. The role of the microbiome and the role of nitric oxide on gut function are important areas of research for understanding gut dysfunction in SSc.
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Affiliation(s)
- Jessica Zhu
- School of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Tracy Frech
- Department of Internal Medicine, Division of Rheumatology, University of Utah, Salt Lake City, UT, USA
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6
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McClatchey PM, Frisbee JC, Reusch JEB. A conceptual framework for predicting and addressing the consequences of disease-related microvascular dysfunction. Microcirculation 2018; 24. [PMID: 28135021 DOI: 10.1111/micc.12359] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 01/25/2017] [Indexed: 12/20/2022]
Abstract
OBJECTIVE A growing body of evidence indicates that impaired microvascular perfusion plays a pathological role in a number of diseases. This manuscript aims to better define which aspects of microvascular perfusion are important, what mass transport processes (eg, insulin action, tissue oxygenation) may be impacted, and what therapies might reverse these pathologies. METHODS We derive a theory of microvascular perfusion and solute flux drawing from established relationships in mass transport and anatomy. We then apply this theory to predict relationships between microvascular perfusion parameters and microvascular solute flux. RESULTS For convection-limited exchange processes (eg, pulmonary oxygen uptake), our model predicts that bulk blood flow is of primary importance. For diffusion-limited exchange processes (eg, insulin action), our model predicts that perfused capillary density is of primary importance. For convection/diffusion co-limited exchange processes (eg, tissue oxygenation), our model predicts that various microvascular perfusion parameters interact in a complex, context-specific manner. We further show that our model can predict established mass transport defects in disease (eg, insulin resistance in diabetes). CONCLUSIONS The contributions of microvascular perfusion parameters to tissue-level solute flux can be described using a minimal mathematical model. Our results hold promise for informing therapeutic interventions targeting microvascular perfusion.
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Affiliation(s)
- Penn M McClatchey
- Division of Endocrinology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.,Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.,Department of Medicine, Denver Veterans Affairs Medical Center, Denver, CO, USA
| | - Jefferson C Frisbee
- Department of Medical Biophysics, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada
| | - Jane E B Reusch
- Division of Endocrinology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.,Department of Medicine, Denver Veterans Affairs Medical Center, Denver, CO, USA
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Machin DR, Bloom SI, Campbell RA, Phuong TTT, Gates PE, Lesniewski LA, Rondina MT, Donato AJ. Advanced age results in a diminished endothelial glycocalyx. Am J Physiol Heart Circ Physiol 2018; 315:H531-H539. [PMID: 29750566 DOI: 10.1152/ajpheart.00104.2018] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Age-related microvascular dysfunction is well characterized in rodents and humans, but little is known about the properties of the microvascular endothelial glycocalyx in advanced age. We examined the glycocalyx in microvessels of young and old male C57BL6 mice (young: 6.1 ± 0.1 mo vs. old: 24.6 ± 0.2 mo) using intravital microscopy and transmission electron microscopy and in human participants (young: 29 ± 1 yr vs. old: 60 ± 2 yr) using intravital microscopy. Glycocalyx thickness in mesenteric and skeletal muscle microvessels was 51-54% lower in old compared with young mice. We also observed 33% lower glycocalyx thickness in the sublingual microcirculation of humans in advanced age. The perfused boundary region, a marker of glycocalyx barrier function, was also obtained using an automated capture and analysis system. In advanced age, we observed a 10-22% greater perfused boundary region in mice and humans, indicating a more penetrable glycocalyx. Finally, using this automated analysis system, we examined perfused microvascular density and red blood cell (RBC) fraction. Perfused microvascular density is a marker of microvascular function that reflects the length of perfused microvessel segments in a given area; RBC fraction represents the heterogeneity in RBC presence between microvessel segments. Compared with young, the perfused microvascular density was 16-21% lower and RBC fraction was 5-14% lower in older mice and in older humans. These data provide novel evidence that, across mammalian species, a diminished glycocalyx is present in advanced age and is accompanied by markers of impaired microvascular perfusion. Age-related glycocalyx deterioration may be an important contributor to microvascular dysfunction in older adults and subsequent pathophysiology. NEW & NOTEWORTHY Advanced age is characterized by microvascular dysfunction that contributes to age-related cardiovascular diseases, but little is known about endothelial glycocalyx properties in advanced age. This study reveals, for the first time, lower glycocalyx thickness and barrier function that is accompanied by impaired microvascular perfusion in both mice and humans in advanced age.
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Affiliation(s)
- Daniel R Machin
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Salt Lake City, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Samuel I Bloom
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Robert A Campbell
- Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Molecular Medicine, University of Utah , Salt Lake City, Utah
| | - Tam T T Phuong
- Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Phillip E Gates
- Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Lisa A Lesniewski
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Salt Lake City, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Matthew T Rondina
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Salt Lake City, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Molecular Medicine, University of Utah , Salt Lake City, Utah
| | - Anthony J Donato
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Salt Lake City, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah.,Department of Biochemistry, University of Utah , Salt Lake City, Utah
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8
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Hall AA, Mendoza MI, Zhou H, Shaughness M, Maudlin-Jeronimo E, McCarron RM, Ahlers ST. Repeated Low Intensity Blast Exposure Is Associated with Damaged Endothelial Glycocalyx and Downstream Behavioral Deficits. Front Behav Neurosci 2017. [PMID: 28649193 PMCID: PMC5465256 DOI: 10.3389/fnbeh.2017.00104] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Current clinical research into mild traumatic brain injury (mTBI) has focused on white matter changes as identified by advanced MRI based imaging techniques. However, perivascular tau accumulation in the brains of individuals diagnosed with mTBI suggests that the vasculature plays a key role in the pathology. This study used a rat model to examine whether the endothelial glycocalyx, a layer of the vasculature responsible for sensing luminal shear forces, is damaged by exposure to repeated low intensity blast, and whether this layer is associated with observed behavioral deficits. The blast exposure used consisted of 12, 40 kPa blast exposures conducted with a minimum of 24 h between blasts. We found that repeated blast exposure reduced glycocalyx length and density in various brain regions indicating damage. This blast exposure paradigm was associated with a mild performance decrement in the Morris water maze (MWM) which assesses learning and memory. Administration of hyaluronidase, an enzyme that binds to and degrades hyaluronan (a major structural component of the glycocalyx) prior to blast exposure reduced the observed behavioral deficits and induced a thickening of the glycocalyx layer. Taken together these findings demonstrate that the endothelial glycocalyx degradation following repeated blast is associated with behavioral decrements which can be prevented by treatment with hyaluronidase.
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Affiliation(s)
- Aaron A Hall
- Neurotrauma Department, Operational and Undersea Medicine, Naval Medical Research Center, Silver SpringMD, United States
| | - Mirian I Mendoza
- Neurotrauma Department, Operational and Undersea Medicine, Naval Medical Research Center, Silver SpringMD, United States
| | - Hanbing Zhou
- Neurotrauma Department, Operational and Undersea Medicine, Naval Medical Research Center, Silver SpringMD, United States
| | - Michael Shaughness
- Neurotrauma Department, Operational and Undersea Medicine, Naval Medical Research Center, Silver SpringMD, United States
| | - Eric Maudlin-Jeronimo
- Neurotrauma Department, Operational and Undersea Medicine, Naval Medical Research Center, Silver SpringMD, United States
| | - Richard M McCarron
- Neurotrauma Department, Operational and Undersea Medicine, Naval Medical Research Center, Silver SpringMD, United States
| | - Stephen T Ahlers
- Neurotrauma Department, Operational and Undersea Medicine, Naval Medical Research Center, Silver SpringMD, United States
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9
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van Haare J, Kooi ME, van Teeffelen JWGE, Vink H, Slenter J, Cobelens H, Strijkers GJ, Koehn D, Post MJ, van Bilsen M. Metformin and sulodexide restore cardiac microvascular perfusion capacity in diet-induced obese rats. Cardiovasc Diabetol 2017; 16:47. [PMID: 28399917 PMCID: PMC5387275 DOI: 10.1186/s12933-017-0525-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 03/25/2017] [Indexed: 12/26/2022] Open
Abstract
Background Disturbances in coronary microcirculatory function, such as the endothelial glycocalyx, are early hallmarks in the development of obesity and insulin resistance. Accordingly, in the present study myocardial microcirculatory perfusion during rest and stress was assessed following metformin or sulodexide therapy in a rat model of diet-induced obesity. Additionally, the effect of degradation of the glycocalyx on myocardial perfusion was assessed in chow-fed rats. Methods Rats were fed a high fat diet (HFD) for 8 weeks and were divided into a group without therapy, and groups that received the anti-diabetic drug metformin or the glycocalyx-stabilizing drug sulodexide in their drinking water during the last 4 weeks of the feeding period. Myocardial microvascular perfusion was determined using first-pass perfusion MRI before and after adenosine infusion. The effect of HFD on microcirculatory properties was also assessed by sidestream darkfield (SDF) imaging of the gastrocnemius muscle. In an acute experimental setting, hyaluronidase was administered to chow-fed control rats to determine the effect of enzymatical degradation of the glycocalyx on myocardial perfusion. Results HFD-rats developed central obesity and insulin sensitivity was reduced as evidenced by the marked reduction in insulin-induced phosphorylation of Akt in both cardiac and gastrocnemius muscle. We confirmed our earlier findings that the robust increase in myocardial perfusion in chow-fed rats after an adenosine challenge (+56%, p = 0.002) is blunted in HFD rats (+8%, p = 0.68). In contrast, 4-weeks treatment with metformin or sulodexide partly restored the increase in myocardial perfusion during adenosine infusion in HFD rats (+81%, p = 0.002 and +37%, p = 0.02, respectively). Treating chow-fed rats acutely with hyaluronidase, to enzymatically degrade the glyocalyx, completely blunted the increase in myocardial perfusion during stress. Conclusions In early stages of HFD-induced insulin resistance myocardial perfusion becomes compromised, a process that can be countered by treatment with both metformin and sulodexide. The adverse effect of acute glycocalyx degradation and protective effect of long-term sulodexide administration on myocardial perfusion provides indirect evidence, suggesting a role for the glycocalyx in preserving coronary microvascular function in pre-diabetic animals.
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Affiliation(s)
- Judith van Haare
- Department of Physiology, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | - M Eline Kooi
- Department of Radiology and Nuclear Medicine, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | | | - Hans Vink
- Department of Physiology, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | - Jos Slenter
- Department of Radiology and Nuclear Medicine, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | - Hanneke Cobelens
- Department of Physiology, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | - Gustav J Strijkers
- Biomedical Engineering and Physics, Academic Medical Center, P.O. Box 22700, 1100 DE, Amsterdam, The Netherlands
| | - Dennis Koehn
- Pie Medical Imaging, P.O. Box 1132, 6201 BC, Maastricht, The Netherlands
| | - Mark J Post
- Department of Physiology, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | - Marc van Bilsen
- Department of Physiology, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands. .,Department of Cardiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
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10
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Coan PM, Hummel O, Garcia Diaz A, Barrier M, Alfazema N, Norsworthy PJ, Pravenec M, Petretto E, Hübner N, Aitman TJ. Genetic, physiological and comparative genomic studies of hypertension and insulin resistance in the spontaneously hypertensive rat. Dis Model Mech 2017; 10:297-306. [PMID: 28130354 PMCID: PMC5374317 DOI: 10.1242/dmm.026716] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 01/23/2017] [Indexed: 12/18/2022] Open
Abstract
We previously mapped hypertension-related insulin resistance quantitative trait loci (QTLs) to rat chromosomes 4, 12 and 16 using adipocytes from F2 crosses between spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats, and subsequently identified Cd36 as the gene underlying the chromosome 4 locus. The identity of the chromosome 12 and 16 genes remains unknown. To identify whole-body phenotypes associated with the chromosome 12 and 16 linkage regions, we generated and characterised new congenic strains, with WKY donor segments introgressed onto an SHR genetic background, for the chromosome 12 and 16 linkage regions. We found a >50% increase in insulin sensitivity in both the chromosome 12 and 16 strains. Blood pressure and left ventricular mass were reduced in the two congenic strains consistent with the congenic segments harbouring SHR genes for insulin resistance, hypertension and cardiac hypertrophy. Integrated genomic analysis, using physiological and whole-genome sequence data across 42 rat strains, identified variants within the congenic regions in Upk3bl, RGD1565131 and AABR06087018.1 that were associated with blood pressure, cardiac mass and insulin sensitivity. Quantitative trait transcript analysis across 29 recombinant inbred strains showed correlation between expression of Hspb1, Zkscan5 and Pdgfrl with adipocyte volume, systolic blood pressure and cardiac mass, respectively. Comparative genome analysis showed a marked enrichment of orthologues for human GWAS-associated genes for insulin resistance within the syntenic regions of both the chromosome 12 and 16 congenic intervals. Our study defines whole-body phenotypes associated with the SHR chromosome 12 and 16 insulin-resistance QTLs, identifies candidate genes for these SHR QTLs and finds human orthologues of rat genes in these regions that associate with related human traits. Further study of these genes in the congenic strains will lead to robust identification of the underlying genes and cellular mechanisms. Summary: Comparative genome analyses identify candidate genes for hypertension and insulin resistance on rat chromosomes 12 and 16, and marked enrichment of insulin resistance genes in the syntenic regions of the human genome.
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Affiliation(s)
- Philip M Coan
- Centre for Genomic and Experimental Medicine & Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Oliver Hummel
- Cardiovascular and Metabolic Sciences, Max-Delbrück-Center for Molecular Medicine (MDC), 13125 Berlin, Germany
| | - Ana Garcia Diaz
- Department of Medicine, Imperial College London, London SW7 2AZ, UK
| | - Marjorie Barrier
- Centre for Genomic and Experimental Medicine & Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Neza Alfazema
- Centre for Genomic and Experimental Medicine & Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Penny J Norsworthy
- MRC Clinical Sciences Centre, Imperial College London, London W12 0NN, UK
| | - Michal Pravenec
- Department of Model Diseases, Institute of Physiology, Czech Academy of Sciences, 142 20 Prague, Czech Republic
| | - Enrico Petretto
- MRC Clinical Sciences Centre, Imperial College London, London W12 0NN, UK.,Duke-NUS Medical School, Singapore 169857, Republic of Singapore
| | - Norbert Hübner
- Cardiovascular and Metabolic Sciences, Max-Delbrück-Center for Molecular Medicine (MDC), 13125 Berlin, Germany.,DZHK (German Centre for Cardiovascular Research), partner site, 13316 Berlin, Germany.,Charité-Universitätsmedizin, 10117 Berlin, Germany
| | - Timothy J Aitman
- Centre for Genomic and Experimental Medicine & Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH4 2XU, UK.,Department of Medicine, Imperial College London, London SW7 2AZ, UK
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11
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Mahmoud AM, Brown MD, Phillips SA, Haus JM. Skeletal Muscle Vascular Function: A Counterbalance of Insulin Action. Microcirculation 2016; 22:327-47. [PMID: 25904196 DOI: 10.1111/micc.12205] [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: 01/06/2015] [Accepted: 04/20/2015] [Indexed: 12/11/2022]
Abstract
Insulin is a vasoactive hormone that regulates vascular homeostasis by maintaining balance of endothelial-derived NO and ET-1. Although there is general agreement that insulin resistance and the associated hyperinsulinemia disturb this balance, the vascular consequences for hyperinsulinemia in isolation from insulin resistance are still unclear. Presently, there is no simple answer for this question, especially in a background of mixed reports examining the effects of experimental hyperinsulinemia on endothelial-mediated vasodilation. Understanding the mechanisms by which hyperinsulinemia induces vascular dysfunction is essential in advancing treatment and prevention of insulin resistance-related vascular complications. Thus, we review literature addressing the effects of hyperinsulinemia on vascular function. Furthermore, we give special attention to the vasoregulatory effects of hyperinsulinemia on skeletal muscle, the largest insulin-dependent organ in the body. This review also characterizes the differential vascular effects of hyperinsulinemia on large conduit vessels versus small resistance microvessels and the effects of metabolic variables in an effort to unravel potential sources of discrepancies in the literature. At the cellular level, we provide an overview of insulin signaling events governing vascular tone. Finally, we hypothesize a role for hyperinsulinemia and insulin resistance in the development of CVD.
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Affiliation(s)
- Abeer M Mahmoud
- Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, Illinois, USA.,Integrative Physiology Laboratory, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Michael D Brown
- Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, Illinois, USA.,Integrative Physiology Laboratory, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Shane A Phillips
- Integrative Physiology Laboratory, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Physical Therapy, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Jacob M Haus
- Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, Illinois, USA.,Integrative Physiology Laboratory, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
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12
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Nussbaum C, Haberer A, Tiefenthaller A, Januszewska K, Chappell D, Brettner F, Mayer P, Dalla Pozza R, Genzel-Boroviczény O. Perturbation of the microvascular glycocalyx and perfusion in infants after cardiopulmonary bypass. J Thorac Cardiovasc Surg 2015; 150:1474-81.e1. [DOI: 10.1016/j.jtcvs.2015.08.050] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 07/29/2015] [Accepted: 08/19/2015] [Indexed: 11/27/2022]
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13
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van Haare J, Kooi ME, Vink H, Post MJ, van Teeffelen JWGE, Slenter J, Munts C, Cobelens H, Strijkers GJ, Koehn D, van Bilsen M. Early impairment of coronary microvascular perfusion capacity in rats on a high fat diet. Cardiovasc Diabetol 2015; 14:150. [PMID: 26576929 PMCID: PMC4650915 DOI: 10.1186/s12933-015-0312-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 11/06/2015] [Indexed: 02/05/2023] Open
Abstract
Background It remains to be established if, and to what extent, the coronary microcirculation becomes compromised during the development of obesity and insulin resistance. Recent studies suggest that changes in endothelial glycocalyx properties contribute to microvascular dysfunction under (pre-)diabetic conditions. Accordingly, early effects of diet-induced obesity on myocardial perfusion and function were studied in rats under baseline and hyperaemic conditions. Methods Rats were fed a high fat diet (HFD) for 6 weeks and myocardial microvascular perfusion was determined using first-pass perfusion MRI before and after adenosine infusion. The effect of HFD on microcirculatory properties was also assessed by sidestream darkfield (SDF) imaging of the gastrocnemius muscle. Results HFD-fed rats developed central obesity and insulin sensitivity was reduced as evidenced by the marked reduction in insulin-induced phosphorylation of Akt in both cardiac and gastrocnemius muscle. Early diet-induced obesity did not lead to hypertension or cardiac hypertrophic remodeling. In chow-fed, control rats a robust increase in cardiac microvascular perfusion was observed upon adenosine infusion (+40 %; p < 0.05). In contrast, the adenosine response was abrogated in rats on a HFD (+8 %; N.S.). HFD neither resulted in rarefaction or loss of glycocalyx integrity in skeletal muscle, nor reduced staining intensity of the glycocalyx of cardiac capillaries. Conclusions Alterations in coronary microcirculatory function as assessed by first-pass perfusion MRI represent one of the earliest obesity-related cardiac adaptations that can be assessed non-invasively. In this early stage of insulin resistance, disturbances in glycocalyx barrier properties appeared not to contribute to the observed changes in coronary microvascular function.
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Affiliation(s)
- Judith van Haare
- Department of Physiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | - M Eline Kooi
- Department of Radiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Hans Vink
- Department of Physiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Mark J Post
- Department of Physiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Jurgen W G E van Teeffelen
- Department of Physiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Jos Slenter
- Department of Radiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Chantal Munts
- Department of Physiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Hanneke Cobelens
- Department of Physiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Gustav J Strijkers
- Biomedical Engineering and Physics, Academic Medical Center, P.O. Box 22700, 1100 DE, Amsterdam, The Netherlands.
| | - Dennis Koehn
- Pie Medical Imaging, P.O. Box 1132, 6201 BC, Maastricht, The Netherlands.
| | - Marc van Bilsen
- Department of Physiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands. .,Department of Cardiology, CARIM School for Cardiovascular Diseases, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
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14
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Affiliation(s)
- David C Poole
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA Department of Anatomy & Physiology, Kansas State University, Manhattan, KS, USA
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15
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Poole DC. CrossTalk opposing view: De novo capillary recruitment in healthy muscle is not necessary to explain physiological outcomes. J Physiol 2015; 592:5133-5. [PMID: 25448179 DOI: 10.1113/jphysiol.2014.282145] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- David C Poole
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA Department of Anatomy & Physiology, Kansas State University, Manhattan, KS, USA
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16
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Amraoui F, Olde Engberink RHG, van Gorp J, Ramdani A, Vogt L, van den Born BJH. Microvascular Glycocalyx Dimension Estimated by Automated SDF Imaging is not Related to Cardiovascular Disease. Microcirculation 2014; 21:499-505. [DOI: 10.1111/micc.12125] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 02/26/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Fouad Amraoui
- Department of Vascular Medicine; Academic Medical Center; Amsterdam The Netherlands
| | | | - Jacqueline van Gorp
- Department of Vascular Medicine; Academic Medical Center; Amsterdam The Netherlands
| | - Amal Ramdani
- Department of Vascular Medicine; Academic Medical Center; Amsterdam The Netherlands
| | - Liffert Vogt
- Department of Nephrology; Academic Medical Center; Amsterdam The Netherlands
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17
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Acute enzymatic glycocalyx degradation results in reduced insulin sensitivity but normal glucose tolerance in conscious rats. Cardiovasc Endocrinol 2014. [DOI: 10.1097/xce.0000000000000017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Deeper penetration of erythrocytes into the endothelial glycocalyx is associated with impaired microvascular perfusion. PLoS One 2014; 9:e96477. [PMID: 24816787 PMCID: PMC4015985 DOI: 10.1371/journal.pone.0096477] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 04/07/2014] [Indexed: 11/25/2022] Open
Abstract
Changes in endothelial glycocalyx are one of the earliest changes in development of cardiovascular disease. The endothelial glycocalyx is both an important biological modifier of interactions between flowing blood and the vessel wall, and a determinant of organ perfusion. We hypothesize that deeper penetration of erythrocytes into the glycocalyx is associated with reduced microvascular perfusion. The population-based prospective cohort study (the Netherlands Epidemiology of Obesity [NEO] study) includes 6,673 middle-aged individuals (oversampling of overweight and obese individuals). Within this cohort, we have imaged the sublingual microvasculature of 915 participants using sidestream darkfield (SDF) imaging together with a recently developed automated acquisition and analysis approach. Presence of RBC (as a marker of microvascular perfusion) and perfused boundary region (PBR), a marker for endothelial glycocalyx barrier properties for RBC accessibility, were assessed in vessels between 5 and 25 µm RBC column width. A wide range of variability in PBR measurements, with a mean PBR of 2.14 µm (range: 1.43–2.86 µm), was observed. Linear regression analysis showed a marked association between PBR and microvascular perfusion, reflected by RBC filling percentage (regression coefficient β: −0.034; 95% confidence interval: −0.037 to −0.031). We conclude that microvascular beds with a thick (“healthy”) glycocalyx (low PBR), reflects efficient perfusion of the microvascular bed. In contrast, a thin (“risk”) glycocalyx (high PBR) is associated with a less efficient and defective microvascular perfusion.
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Groen BBL, Hamer HM, Snijders T, van Kranenburg J, Frijns D, Vink H, van Loon LJC. Skeletal muscle capillary density and microvascular function are compromised with aging and type 2 diabetes. J Appl Physiol (1985) 2014; 116:998-1005. [DOI: 10.1152/japplphysiol.00919.2013] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Adequate muscle perfusion is required for the maintenance of skeletal muscle mass. Impairments in microvascular structure and/or function with aging and type 2 diabetes have been associated with the progressive loss of skeletal muscle mass. Our objective was to compare muscle fiber type specific capillary density and endothelial function between healthy young men, healthy older men, and age-matched type 2 diabetes patients. Fifteen healthy young men (24 ± 1 yr), 15 healthy older men (70 ± 2 yr), and 15 age-matched type 2 diabetes patients (70 ± 1 yr) were selected to participate in the present study. Whole body insulin sensitivity, muscle fiber type specific capillary density, sublingual microvascular density, and dimension of the erythrocyte-perfused boundary region were assessed to evaluate the impact of aging and/or type 2 diabetes on microvascular structure and function. Whole body insulin sensitivity was significantly lower at a more advanced age, with lowest values reported in the type 2 diabetic patients. In line, skeletal muscle capillary contacts were much lower in the older and older type 2 diabetic patients when compared with the young. Sidestream darkfield imaging showed a significantly greater thickness of the erythrocyte perfused boundary region in the type 2 diabetic patients compared with the young. Skeletal muscle capillary density is reduced with aging and type 2 diabetes and accompanied by impairments in endothelial glycocalyx function, which is indicative of compromised vascular function.
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Affiliation(s)
- Bart B. L. Groen
- Department of Human Movement Sciences, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands; and
| | - Henrike M. Hamer
- Department of Human Movement Sciences, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands; and
| | - Tim Snijders
- Department of Human Movement Sciences, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands; and
| | - Janneau van Kranenburg
- Department of Human Movement Sciences, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands; and
| | - Dionne Frijns
- Department of Human Movement Sciences, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands; and
| | - Hans Vink
- Department of Physiology, CARIM School for Cardiovascular Disease, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Luc J. C. van Loon
- Department of Human Movement Sciences, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands; and
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Eskens BJM, Leurgans TM, Vink H, Vanteeffelen JWGE. Early impairment of skeletal muscle endothelial glycocalyx barrier properties in diet-induced obesity in mice. Physiol Rep 2014; 2:e00194. [PMID: 24744873 PMCID: PMC3967677 DOI: 10.1002/phy2.194] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 12/03/2013] [Accepted: 12/08/2013] [Indexed: 01/05/2023] Open
Abstract
While previous studies have indicated an important role for the endothelial glycocalyx in regulation of microvascular function, it was recently shown that acute enzymatic glycocalyx degradation in rats was associated with an impaired insulin‐mediated glucose disposal. The aim of this study was to determine whether glycocalyx damage in skeletal muscle occurs at an early stage of diet‐induced obesity (DIO). The microcirculation of the hindlimb muscle of anesthetized C57Bl/6 mice, fed chow (CON) or a high‐fat diet (HFD) for 6 and 18 weeks (w), respectively, was visualized with a Sidestream Dark‐Field camera, and glycocalyx barrier properties were derived from the calculated perfused boundary region (PBR). Subsequently, an intraperitoneal glucose tolerance test was performed and the area under the curve (AUC) of blood glucose was calculated. Impairment of glycocalyx barrier properties was already apparent after 6 weeks of HFD and remained after 18 weeks of HFD (PBR [in μm]: 0.81 ± 0.03 in CON_6w vs. 0.97 ± 0.04 in HFD_6w and 1.02 ± 0.07 in HFD_18w [both P < 0.05]). Glucose intolerance appeared to develop more slowly (AUC [in mmol/L × 120 min]: 989 ± 61 in CON_6w vs. 1204 ± 89 in HFD_6w [P = 0.11] and 1468 ± 84 in HFD_18w [P < 0.05]) than the impairment of glycocalyx barrier properties. The data indicate that damage to the endothelial glycocalyx is an early event in DIO. It is suggested that glycocalyx damage may contribute to the development of insulin resistance in obesity. In this study we assessed glycocalyx barrier properties in skeletal muscle using Sidestream Dark‐Field imaging at an early and later stage of diet‐induced obesity in mice, by feeding them a high‐fat diet for 6 and 18 weeks, respectively. Glycocalyx barrier properties in hindlimb muscle microcirculation were found to be impaired after 6 weeks already. Our results suggest that in obesity glycocalyx damage represents an early aspect of microvascular dysfunction which may as well contribute to the development of glucose intolerance.
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Affiliation(s)
- Bart J M Eskens
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Thomas M Leurgans
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Hans Vink
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Jurgen W G E Vanteeffelen
- Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
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