title: Impairments in microvascular function and skeletal muscle oxygenation in women with gestational diabetes mellitus: links to cardiovascular disease risk factors.
abstract: Gestational diabetes mellitus (GDM) is a risk factor for the development of endothelial dysfunction and cardiovascular disease. However, in vivo microvascular endothelial function in GDM has not been investigated. This study aimed to examine, using near-infrared spectroscopy (NIRS), whether: (1) there are differences in microvascular reactivity and skeletal muscle oxygen consumption (m[Formula: see text]) at rest and during exercise between GDM and uncomplicated pregnancies; and (2) there is an association of NIRS indices with macrovascular function and cardiovascular disease risk factors.
  
  
  
  Twenty-nine pregnant women (13 with GDM and 16 women with uncomplicated pregnancy, 28 ± 2 gestational weeks) underwent arterial stiffness (pulse wave velocity [PWV]) and 24 h ambulatory BP (24 h BP) evaluation. NIRS continuously monitored, non-invasively, changes in muscle oxygenated and deoxygenated haemoglobin and tissue O2saturation index (TSI, %) during arterial occlusion/reperfusion and intermittent handgrip exercise. m[Formula: see text] and vascular reactivity indices were calculated.
  
  
  
  During occlusion and reperfusion, women with GDM exhibited slower TSI response (occlusion slope: -0.06 ± 0.02 vs -0.10 ± 0.04, in GDM and controls, respectively; reperfusion slope: 0.65 ± 0.26 vs 1.05 ± 0.41, respectively), lower m[Formula: see text] (1.3 ± 1.2 vs 3.8 ± 2.3 μmol l-1min-1) and blunted hyperaemia (ΔTSI 6.8 ± 2.9 vs 9.5 ± 3.4) compared with controls (p < 0.01). Despite similar handgrip strength in the GDM and control groups (29.1 ± 8.1 vs 26.2 ± 10.4 kg, respectively), during repeated forearm contractions, women with GDM presented a blunted TSI response (6.5 ± 3.9 vs 19.2 ± 10.9; p < 0.01) and a reduced capacity to maintain the predetermined handgrip (23.4 ± 2.9 vs 27.4 ± 3.8%, p < 0.05). NIRS indices correlated with PWV, 24 h BP and blood glucose concentration earlier in pregnancy (r = 0.40-0.60; p < 0.05).
  
  
  
  Women with GDM exhibited a characteristic blunted TSI curve, showing alterations in muscle oxygenation and microvascular responsiveness compared with women with uncomplicated pregnancies. These alterations were manifested during exercise and possibly contribute to the reduced exercise tolerance in GDM. NIRS indices correlated with macrovascular indices (arterial stiffness) and 24 h BP.
authors.affiliation: Laboratory of Exercise Physiology and Biochemistry, Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Ippokratous 22, Agios Ioannis, Serres, 62110, Greece. kdipla@phed-sr.auth.gr.
authors.forename: Konstantina
authors.identifier: 0000-0001-5902-3467
authors.initials: K
authors.lastname: Dipla
authors.affiliation: Third Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Areti
authors.initials: A
authors.lastname: Triantafyllou
authors.affiliation: Laboratory of Exercise Physiology and Biochemistry, Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Ippokratous 22, Agios Ioannis, Serres, 62110, Greece.
authors.forename: Iris
authors.initials: I
authors.lastname: Grigoriadou
authors.affiliation: Unit of Reproductive Endocrinology, First Department of Obstetrics and Gynaecology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Evangelia
authors.initials: E
authors.lastname: Kintiraki
authors.affiliation: Third Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Georgios A
authors.initials: GA
authors.lastname: Triantafyllou
authors.affiliation: Third Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Pavlos
authors.initials: P
authors.lastname: Poulios
authors.affiliation: Laboratory of Exercise Physiology and Biochemistry, Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Ippokratous 22, Agios Ioannis, Serres, 62110, Greece.
authors.forename: Ioannis S
authors.initials: IS
authors.lastname: Vrabas
authors.affiliation: Laboratory of Exercise Physiology and Biochemistry, Department of Physical Education and Sports Science at Serres, Aristotle University of Thessaloniki, Ippokratous 22, Agios Ioannis, Serres, 62110, Greece.
authors.forename: Andreas
authors.initials: A
authors.lastname: Zafeiridis
authors.affiliation: Third Department of Internal Medicine, Papageorgiou Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Stella
authors.initials: S
authors.lastname: Douma
authors.affiliation: Unit of Reproductive Endocrinology, First Department of Obstetrics and Gynaecology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Dimitrios G
authors.initials: DG
authors.lastname: Goulis
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000502:physiology; D002318:Cardiovascular Diseases / Q000378:metabolism*; D016640:Diabetes, Gestational / Q000378:metabolism / Q000503:physiopathology*; D005260:Female; D006801:Humans; D018482:Muscle, Skeletal / Q000503:physiopathology; D010101:Oxygen Consumption / Q000502:physiology; D011247:Pregnancy; D063177:Pulse Wave Analysis; D012307:Risk Factors; D019265:Spectroscopy, Near-Infrared; D059289:Vascular Stiffness / Q000502:physiology
chemical_list: D001786:Blood Glucose
keywords: Arterial stiffness; Endothelial function; Exercise; Gestational diabetes mellitus; Microvascular function; Near-infrared spectroscopy; Pulse wave velocity; Skeletal muscle oxygen consumption; Vascular reactivity