Exercise training induces thrombogenic benefits in recent but not late postmenopausal females.

Although regular physical activity is known to improve cardiovascular health in men, evidence for its beneficial effects in postmenopausal females is less convincing and it remains unclear whether initiation of exercise training soon after, rather than many years after menopause impacts the magnitude of training-induced adaptations. We evaluated exercise-induced changes in markers of thrombotic risk and conduit artery function in recent≤5yr compared with late≥10yr postmenopausal females. Fourteen recent≤5yr and 13 late≥10yr healthy postmenopausal females completed 8 wk of regular intensive exercise training, consisting of floorball and cycling. Markers of thrombotic risk and vascular health were assessed before and after the intervention, and data were analyzed using a linear mixed model. Exercise training reduced markers of thrombotic risk, including an 11% reduction (P = 0.007) in agonist-induced platelet reactivity and a reduction (P = 0.027) in incipient clot microstructure (∼40% reduction in clot mass) in the recent≤5yr but not the late≥10yr (P = 0.380; P = 0.739, respectively) postmenopausal females. There was no change in conduit artery function, as measured by brachial (recent≤5yr, P = 0.804; late≥10yr, P = 0.311) and popliteal artery (recent≤5yr, P = 0.130; late≥10yr, P = 0.434) flow-mediated dilation. Only the late≥10yr postmenopausal females exhibited an increase (by 9.6%, P = 0.022) in intracellular adhesion molecule-1 levels after training, which may have impacted the thrombogenic adaptation in this group. These findings suggest that 8 wk of high-intensity exercise training reduces thrombotic risk in recent≤5yr, but not late≥10yr postmenopausal females. Thus, regular physical activity initiated soon after, rather than many years after menopause and at a higher age, may be more efficient for reducing thrombogenic risk.NEW & NOTEWORTHY Eight weeks of high-intensity exercise training reduces platelet reactivity as well as blood clot density and strength in females ≤5 yr past menopause but not in females ≥10 yr past menopause. The divergent response in the late postmenopausal females may be explained by training-induced low-grade systemic inflammation. These findings suggest that regular physical activity initiated soon after menopause, compared with many years after menopause, may be more efficient for reducing the risk of blood clots.

NEDD9 Is a Novel and Modifiable Mediator of Platelet-Endothelial Adhesion in the Pulmonary Circulation.

Rationale: Data on the molecular mechanisms that regulate platelet-pulmonary endothelial adhesion under conditions of hypoxia are lacking, but may have important therapeutic implications. Objectives: To identify a hypoxia-sensitive, modifiable mediator of platelet-pulmonary artery endothelial cell adhesion and thrombotic remodeling. Methods: Network medicine was used to profile protein-protein interactions in hypoxia-treated human pulmonary artery endothelial cells. Data from liquid chromatography-mass spectrometry and microscale thermophoresis informed the development of a novel antibody (Ab) to inhibit platelet-endothelial adhesion, which was tested in cells from patients with chronic thromboembolic pulmonary hypertension (CTEPH) and three animal models in vivo. Measurements and Main Results: The protein NEDD9 was identified in the hypoxia thrombosome network in silico. Compared with normoxia, hypoxia (0.2% O2) for 24 hours increased HIF-1α (hypoxia-inducible factor-1α)-dependent NEDD9 upregulation in vitro. Increased NEDD9 was localized to the plasma-membrane surface of cells from control donors and patients with CTEPH. In endarterectomy specimens, NEDD9 colocalized with the platelet surface adhesion molecule P-selectin. Our custom-made anti-NEDD9 Ab targeted the NEDD9-P-selectin interaction and inhibited the adhesion of activated platelets to pulmonary artery endothelial cells from control donors in vitro and from patients with CTEPH ex vivo. Compared with control mice, platelet-pulmonary endothelial aggregates and pulmonary hypertension induced by ADP were decreased in NEDD9-/- mice or wild-type mice treated with the anti-NEDD9 Ab, which also decreased chronic pulmonary thromboembolic remodeling in vivo. Conclusions: The NEDD9-P-selectin protein-protein interaction is a modifiable target with which to inhibit platelet-pulmonary endothelial adhesion and thromboembolic vascular remodeling, with potential therapeutic implications for patients with disorders of increased hypoxia signaling pathways, including CTEPH.

Effects of high-intensity training on cardiovascular risk factors in premenopausal and postmenopausal women.

BACKGROUND: Menopause is associated with increased risk of cardiovascular disease and the causal factors have been proposed to be the loss of estrogen and the subsequent alterations of the hormonal milieu. However, which factors contribute to the deterioration of cardiometabolic health in postmenopausal women is debated as the menopausal transition is also associated with increased age and fat mass. Furthermore, indications of reduced cardiometabolic adaptations to exercise in postmenopausal women add to the adverse health profile. OBJECTIVE: We sought to evaluate risk factors for type 2 diabetes and cardiovascular disease in late premenopausal and early postmenopausal women, matched by age and body composition, and investigate the effect of high-intensity training. STUDY DESIGN: A 3-month high-intensity aerobic training intervention, involving healthy, nonobese, late premenopausal (n = 40) and early postmenopausal (n = 39) women was conducted and anthropometrics, body composition, blood pressure, lipid profile, glucose tolerance, and maximal oxygen consumption were determined at baseline and after the intervention. RESULTS: At baseline, the groups matched in anthropometrics and body composition, and only differed by 4.2 years in age (mean [95% confidence limits] 49.2 [48.5-49.9] vs 53.4 [52.4-54.4] years). Time since last menstrual period for the postmenopausal women was (mean [95% confidence limits] 3.1 [2.6-3.7] years). Hormonal levels (estrogen, follicle stimulation hormone, luteinizing hormone) confirmed menopausal status. At baseline the postmenopausal women had higher total cholesterol (P < .001), low-density lipoprotein-cholesterol (P < .05), and high-density lipoprotein-cholesterol (P < .001) than the premenopausal women. The training intervention reduced body weight (P < .01), waist circumference (P < .01), and improved body composition by increasing lean body mass (P < .001) and decreasing fat mass (P < .001) similarly in both groups. Moreover, training resulted in lower diastolic blood pressure (P < .05), resting heart rate (P < .001), total cholesterol (P < .01), low-density lipoprotein-cholesterol (P < .01), total cholesterol/high-density lipoprotein-cholesterol index (P < .01), and improved plasma insulin concentration during the oral glucose tolerance test (P < .05) in both groups. CONCLUSION: Cardiovascular risk factors are similar in late premenopausal and early postmenopausal women, matched by age and body composition, with the exception that postmenopausal women have higher high- and low-density lipoprotein-cholesterol levels. A 3-month intervention of high-intensity aerobic training reduces risk factors for type 2 diabetes and cardiovascular disease to a similar extent in late premenopausal and early postmenopausal women.

High-Intensity Exercise Training Improves Basal Platelet Prostacyclin Sensitivity and Potentiates the Response to Dual Anti-Platelet Therapy in Postmenopausal Women.

The risk of thrombotic events dramatically increases with age and may be accelerated in women by the cessation of endogenous estrogen production at menopause. Patients at risk of thrombosis are prescribed dual anti-platelet therapy (DAPT; aspirin and a P2Y12 antagonist) and are encouraged to participate in regular physical activity, as these modalities improve nitric oxide and prostacyclin-mediated inhibition of platelet aggregation. METHODS: We assessed prostacyclin sensitivity as well as basal platelet reactivity with and without in vitro DAPT before and after an 8-week high-intensity exercise training program in 13 healthy, sedentary postmenopausal women. The training intervention consisted of three 1 h sessions per week. Isolated platelets were analyzed for thromboxane A2 receptor, thromboxane A2 synthase, cyclooxygenase-1, and prostacyclin receptor protein expression. Additionally, plasma 6-keto prostaglandin F1α and thromboxane B2 levels were determined. RESULTS: Exercise training made platelets more sensitive to the inhibitory effects of prostacyclin on thromboxane-, collagen-, and adenosine 5'-diphosphate (ADP)-induced aggregation, as well as thrombin-receptor activator peptide 6- and ADP-induced aggregation with DAPT. However, there was no change in protein expression from isolated platelets or plasma thromboxane B2 and prostacyclin levels following training. CONCLUSION: Together, these findings emphasize the importance of promoting physical activity as a tool for reducing thrombotic risk in postmenopausal women and suggest that training status should be considered when prescribing DAPT in this cohort.

Combination of cyclic nucleotide modulators with P2Y12 receptor antagonists as anti-platelet therapy.

BACKGROUND: Endothelium-derived prostacyclin and nitric oxide elevate platelet cyclic nucleotide levels and maintain quiescence. We previously demonstrated that a synergistic relationship exists between cyclic nucleotides and P2Y12 receptor inhibition. A number of clinically approved drug classes can modulate cyclic nucleotide tone in platelets including activators of NO-sensitive guanylyl cyclase (GC) and phosphodiesterase (PDE) inhibitors. However, the doses required to inhibit platelets produce numerous side effects including headache. OBJECTIVE: We investigated using GC-activators in combination with P2Y12 receptor antagonists as a way to selectively amplify the anti-thrombotic effect of both drugs. METHODS: In vitro light transmission aggregation and platelet adhesion under flow were performed on washed platelets and platelet rich plasma. Aggregation in whole blood and a ferric chloride-induced arterial thrombosis model were also performed. RESULTS: The GC-activator BAY-70 potentiated the action of the P2Y12 receptor inhibitor prasugrel active metabolite in aggregation and adhesion studies and was associated with raised intra-platelet cyclic nucleotide levels. Furthermore, mice administered sub-maximal doses of the GC activator cinaciguat together with the PDE inhibitor dipyridamole and prasugrel, showed significant inhibition of ex vivo platelet aggregation and significantly reduced in vivo arterial thrombosis in response to injury without alteration in basal carotid artery blood flow. CONCLUSIONS: Using in vitro, ex vivo, and in vivo functional studies, we show that low dose GC activators synergize with P2Y12 inhibition to produce powerful anti-platelet effects without altering blood flow. Therefore, modulation of intra-platelet cyclic nucleotide levels alongside P2Y12 inhibition can provide a strong, focused anti-thrombotic regimen while minimizing vasodilator side effects.