Sophie Møller

The present study aimed to investigate the potential of selected red blood cell surface proteins as biomarkers of altered erythropoiesis. A secondary aim was to determine whether long‐term cryopreservation affects surface protein expression and clinical red blood cell characteristics. Twelve males received subcutaneous injections of recombinant human erythropoietin (rhEpo, 50 IU/kg epoetin β) three times per week for 3 weeks. Venous blood was collected before, during and after treatment. Fresh blood was analyzed for surface protein expression (CD35, CD47, CD55, CD59) by flow cytometry and standard hematology analyzer‐derived red cell characteristics. Samples were cryopreserved and reanalyzed after 2 years. In fresh blood, mean fluorescence intensity for the decay‐accelerating factor CD55 increased ( p < 0.001) with rhEpo treatment, while intensity for the ageing‐dependent CD35, the antiphagocytic CD47 and the membrane attack complex inhibitor CD59 decreased ( p < 0.001), contrary to expectations based on red cell aging. Importantly, the investigated proteins presented significant baseline variation. Compared with fresh blood, cryopreserved cells exhibited a higher mean fluorescence intensity of CD35 and CD47, a lower intensity of CD55 and CD59 and reduced baseline variation but did not reveal clear treatment‐related changes. Cryopreservation increased ( p < 0.05–0.001) variability of MCV, MCH, MCHC, and RDW‐CV. In conclusion, CD35, CD47, CD55, and CD59 were not found to be reliable biomarkers of rhEpo due to inconsistent expression patterns during treatment and substantial baseline variation. Analysis of cryopreserved cells reduced analytical variability but did not improve detection of rhEpo‐induced changes and introduced systematic differences in protein expression and red cell indices compared with fresh blood.

To determine how endurance training influences insulin sensitivity, metabolic flexibility, and mitochondrial function in individuals with and without type 2 diabetes (T2D). Insulin sensitivity (2‐step hyperinsulinaemic–isoglycaemic clamp), metabolic flexibility, and mitochondrial respiratory capacity and H ₂ O ₂ emission were assessed in participants with T2D ( n = 15) and controls ( n = 14) before and after 12 weeks of supervised endurance training. Sensitivity analyses were performed using linear mixed‐effects models including all available participants. At baseline, glucose clearance was lower in individuals with T2D compared with controls. Training increased glucose clearance (mL/min/kg FFM) in both groups, with larger model‐derived improvements in T2D (Step 1: +1.43 [0.88–1.97]; Step 2: +3.18 [2.12–4.23]) than in controls (Step 1: +0.76 [0.21–1.31]; Step 2: +1.49 [0.53–2.45]). The group × time interaction was significant at the higher insulin step. Metabolic flexibility to fat—but not glucose—was reduced in T2D and improved modestly with training. Mitochondrial respiratory capacity did not differ between groups; however, training decreased mitochondria‐specific respiration and H ₂ O ₂ emission normalized to CS activity and respiration. Endurance training enhances insulin sensitivity and fat oxidation in individuals with T2D and induces favorable mitochondrial adaptations, despite the absence of intrinsic mitochondrial dysfunction.

The present study examined and compared the impact of exercise training on redox and molecular properties of human microvascular endothelial cells derived from skeletal muscle biopsies from sedentary recent (RPF, ≤ 5 years as postmenopausal) and late (LPF, ≥ 10 years as postmenopausal) postmenopausal females. Resting skeletal muscle biopsies were obtained before and after 8 weeks of intense aerobic exercise training for isolation of microvascular endothelial cells and determination of skeletal muscle angiogenic proteins and capillarisation. The microvascular endothelial cells were analysed for mitochondrial respiration and production of reactive oxygen species (ROS), glycolysis and proteins related to vascular function, redox balance and oestrogen receptors. Exercise training led to a reduced endothelial cell ROS formation (∼50%; P = 0.009 and P = 0.020 for intact and permeabilized cells (state 3), respectively) in RPF only, with no effect on endothelial mitochondrial capacity in either group. Basal endothelial cell lactate formation was higher (7%; P = 0.028), indicating increased glycolysis, after compared to before the exercise training period in RPF only. Baseline endothelial G protein‐coupled oestrogen receptor (P = 0.028) and muscle capillarisation (P = 0.028) was lower in LPF than in RPF. Muscle vascular endothelial growth factor protein was higher (32%; P = 0.002) following exercise training in LPF only. Exercise training did not influence endothelial cell proliferation or skeletal muscle capillarisation in either group, but the CD31 level in the muscle tissue, indicating endothelial cell content, was higher (>50%; P < 0.05) in both groups. In conclusion, 8 weeks of intense aerobic exercise training reduces ROS formation and enhances glycolysis in microvascular endothelial cells from RPF but does not induce skeletal muscle angiogenesis. image Key points: Late postmenopausal females have been reported to achieve limited vascular adaptations to exercise training. There is a paucity of data on the effect of exercise training on isolated skeletal muscle microvascular endothelial cells (MMECs). In this study the formation of reactive oxygen species in MMECs was reduced and glycolysis increased after 8 weeks of aerobic exercise training in recent but not late postmenopausal females. Late postmenopausal females had lower levels of G protein‐coupled oestrogen receptor in MMECs and lower skeletal muscle capillary density at baseline. Eight weeks of intense exercise training altered MMEC properties but did not induce skeletal muscle angiogenesis in postmenopausal females.

ID 17343 Poster Board 311 Colchicine treatment has known beneficial effects on cardiovascular health and reduces the incidence of cardiovascular disease. Studies in isolated rodent arteries show colchicine enhances β-adrenoceptor-mediated vasodilation. In this translational study, we examined whether this effect of colchicine was present in humans by conducting a double-blinded, placebo controlled intervention study. Middle-aged men with essential hypertension were randomly assigned firstly to acute treatment with either 0.5 mg colchicine or placebo, and subsequently re-randomized for 3 weeks of treatment with either colchicine 0.5 mg twice daily (n=16) or placebo (n=15) followed by a washout period of 48-72 h. The vasodilator responses to isoprenaline, acetylcholine and sodium nitroprusside were determined, as well as arterial pressure, arterial compliance and plasma inflammatory markers. Acute colchicine treatment increased the isoprenaline- and SNP-mediated increase in vascular conductance, but had no effect on the response to acetylcholine. Following the washout period, three weeks of twice daily treatment of colchicine did not induce an accumulated or sustained effect on the β-adrenoceptor response and there was no effect on either arterial pressure, arterial compliance or on the level of measured inflammatory markers. This study provides the first translational evidence for a transient enhancement of β-adrenoceptor-mediated vasodilatation by colchicine in humans. The finding of an acute effect suggests that it may be clinically important to maintain an adequate biovailability of colchicine to support the cardiovascular protective effects that have been observed with colchicine in various clinical trials. This work was supported by a grant from Augustinusfonden (19-3644). TAJ was funded by a Lundbeck Foundation grant (R323-2018-3674). JvH was funded the European Union9s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie scheme (grant agreement no. 081199).

Aims: The aim of this study is to examine whether colchicine improves β adrenoceptor‐mediated vasodilation in humans by conducting a double‐blinded, placebo‐controlled intervention study. Colchicine treatment has known beneficial effects on cardiovascular health and reduces the incidence of cardiovascular disease. Studies in isolated rodent arteries have shown that colchicine can enhance β adrenoceptor‐mediated vasodilation, but this has not been determined in humans.Methods: Middle‐aged men with essential hypertension were randomly assigned firstly to acute treatment with either 0.5 mg colchicine (n = 19) or placebo (n = 12). They were subsequently re‐randomized for 3 weeks of treatment with either colchicine 0.5 mg twice daily (n = 16) or placebo (n = 15) followed by a washout period of 48–72 h. The vasodilator responses to isoprenaline, acetylcholine and sodium nitroprusside were determined as well as arterial pressure, arterial compliance and plasma inflammatory markers.Results: Acute colchicine treatment increased isoprenaline (by 38% for the highest dose) as well as sodium nitroprusside (by 29% main effect) ‐induced vasodilation but had no effect on the response to acetylcholine. The 3‐week colchicine treatment followed by a washout period did not induce an accumulated or sustained effect on the β adrenoceptor response, and there was no effect on arterial pressure, arterial compliance or the level of measured inflammatory markers.Conclusion: Colchicine acutely enhances β adrenoceptor‐ and nitric oxide‐mediated changes in vascular conductance in humans, supporting that the mechanism previously demonstrated in rodents, translates to humans. The results provide novel translational evidence for a transient enhancing effect of colchicine on β adrenoceptor‐mediated vasodilation in humans with essential hypertension.Condensed Preclinical studies in isolated rodent arteries have shown that colchicine can enhance β adrenoceptor‐mediated vasodilation. Here we show that this effect of colchicine can be translated to humans. Acute colchicine treatment was found to increase both isoprenaline‐ and sodium nitroprusside‐induced vasodilation. The study provides the first translational evidence for a transient β adrenoceptor‐mediated vasodilatory effect of colchicine in humans. The finding of an acute effect suggests that it may be clinically important to maintain an adequate bioavailability of colchicine.

Background: This study tested the hypothesis that training reduces resting sympathetic activity and improves baroreflex control in both hypertensive and normotensive men but reduces blood pressure only in hypertensive men.Methods: Middle‐aged/older un‐medicated stage‐1 hypertensive males (mean age 55 ± 3 years; n = 13) and normotensive controls (mean age 60 ± 5 years; n = 12) participated in 8 weeks of supervised high‐intensity interval spinning training. Before and after training, muscle sympathetic nerve activity (MSNA) and blood pressure were measured at rest and during a sympatho‐excitatory cold pressor test (CPT). Based on the measurements, baroreceptor sensitivity and baroreceptor threshold were calculated.Results: Resting MSNA and baroreceptor sensitivity were similar for the hypertensive and the normotensive groups. Training lowered MSNA (p < 0.05), expressed as burst frequency (burst/min), overall, and to a similar extent, in both groups (17% and 27%, respectively, in hypertensive and normotensive group), whereas blood pressure was only significantly (p < 0.05) lowered (by 4 mmHg in both systolic and diastolic pressure) in the hypertensive group. Training did not (p > 0.05) alter the MSNA or blood pressure response to CPT or increase baroreceptor sensitivity but reduced (p < 0.05) the baroreceptor threshold with a main effect for both groups. Training adherence and intensity were similar in both groups yet absolute maximal oxygen uptake increased by 15% in the normotensive group only.Conclusion: The dissociation between the training induced changes in resting MSNA, lack of change in baroreflex sensitivity and the change in blood pressure, suggests that MSNA is not a main cause of the blood pressure reduction with exercise training in un‐medicated middle‐aged/older men.

Aims: Colchicine treatment has known beneficial effects on cardiovascular health and reduces the incidence of cardiovascular disease. Studies in isolated rodent arteries have shown that colchicine can enhance β-adrenoceptor-mediated vasodilation. In this translational study we examined whether this effect of colchicine was present in humans by conducting a double-blinded, placebo controlled intervention study. Methods and Results : Middle-aged men with essential hypertension were randomly assigned firstly to acute treatment with either 0.5 mg colchicine or placebo, and subsequently re-randomized for 3 weeks of treatment with either colchicine 0.5 mg twice daily (n=16) or placebo (n=15) followed by a washout period of 48-72 h. The vasodilator responses to isoprenaline, acetylcholine and sodium nitroprusside, were determined as well as arterial pressure, arterial compliance and plasma inflammatory markers. Acute colchicine treatment increased isoprenaline- (by 38% for the highest dose) as well as SNP- (by 29% main effect) induced vasodilation, but had no effect on the response to acetylcholine. Conclusion: Three weeks of twice daily treatment of colchicine, followed by a wash-out period, did not induce an accumulated or sustained effect on the β-adrenoceptor response and there was no effect on either arterial pressure, arterial compliance or on the level of measured inflammatory markers. The results provide novel translational evidence for a transient enhancing effect of colchicine on β-adrenoceptor-mediated vasodilation in humans with essential hypertension

Background: In preclinical models, the pannexin-1 channel has been shown to be involved in blood pressure regulation through an effect on peripheral vascular resistance. Pannexin-1 releases ATP, which can activate constrictive purinergic receptors on the smooth muscle cells. Pannexin-1 opening is proposed to be mediated by α-adrenergic receptors to potentiate sympathetic constriction. This positions pannexin-1 as a putative pharmacological target in blood pressure regulation in humans. The aim was to provide the first translational evidence for a role of pannexin-1 in essential hypertension in humans by use of an advanced invasive mechanistic approach. Methods: Middle-aged stage-1 hypertensive (n=13; 135.7±6.4 over 83.7±3.7 mm Hg) and normotensive men (n=12; 117.3±5.7 over 72.2±3.5 mm Hg) were included. Blood pressure and leg vascular resistance were determined during femoral arterial infusion of tyramine (α-adrenergic receptor stimulation), sodium nitroprusside, and acetylcholine. Measurements were made during control conditions and with pannexin-1 blockade (3000 mg probenecid). Expression of Pannexin-1, purinergic- and α-adrenergic receptors in skeletal muscle biopsies was determined by Western blot. Results: The changes in leg vascular resistance in response to tyramine (+289% versus +222%), sodium nitroprusside (−82% versus −78%) and acetylcholine (−40% versus −44%) infusion were not different between the 2 groups ( P >0.05) and pannexin-1 blockade did not alter these variables ( P >0.05). Expression of pannexin-1 and of purinergic- and α-adrenergic receptors was not different between the 2 groups ( P >0.05). Conclusions: Contrary to our hypothesis, the data demonstrate that pannexin-1 does not contribute to the elevated blood pressure in essential hypertension, a finding, which also opposes that reported in preclinical models.