Estrogen-Based Gender-Affirming Hormone Therapy and Subclinical Cardiovascular Disease in Transgender Women with HIV.

Purpose: Transgender women (TW) are disproportionately affected by HIV infection and cardiovascular disease (CVD). This study evaluated whether estrogen-based gender-affirming hormone therapy (GAHT) in TW with HIV (TWH-GAHT) is associated with indices of subclinical CVD. Methods: Of the 40 HIV-seropositive persons enrolled, 20-60 years of age, on antiretroviral treatment with undetectable viral load, assessments were performed on 15 TWH; of these persons, 11 were GAHT treated. These TWH-GAHT were matched with HIV+ cisgender men and women based on age, ethnicity/race, body mass index, and antihypertensive medication use. Sex hormones, and cardiometabolic (waist circumference, blood pressure, insulin resistance, lipid profile, and C-reactive protein), vascular (flow-mediated dilation [FMD] and arterial stiffness), and proinflammatory measures were obtained. Results: TWH-GAHT displayed elevated estradiol and suppressed testosterone levels relative to normative ranges. Analyses indicated the TWH-GAHT displayed lower low-density lipoprotein compared with cisgender groups (p < 0.05). Although no difference was seen on FMD, the central augmentation index of aortic stiffness was higher in cisgender HIV+ women than cisgender HIV+ men (p < 0.05). No other group difference on subclinical CVD markers was observed. For TWH, partial correlations indicated associations of certain sex hormones with selected cardiometabolic outcomes and the inflammatory cytokine, interleukin-8. Conclusion: When well matched to HIV+ cisgender men and women, subclinical CVD pathophysiology did not appear elevated in TWH-GAHT, although tendencies emerged suggesting that some subclinical CVD indices may be higher, but others lower than cisgender groups. Longitudinal studies of TWH are needed to more precisely evaluate the moderating effect of GAHT on cardiometabolic pathophysiology.

Abacavir antiretroviral therapy and indices of subclinical vascular disease in persons with HIV.

OBJECTIVE: Indices of cardiovascular disease (CVD) risk, vascular endothelial dilation, arterial stiffness and endothelial repair were examined in persons with HIV (PWH) on an antiretroviral therapy (ART) that included abacavir (ABC+) in comparison with PWH on ART without abacavir (ABC-), and with HIV seronegative (HIV-) individuals. APPROACH: The 115 participants (63% men), aged 30-50 years, did not have CVD, metabolic, endocrine, or chronic renal conditions. PWH were on stable ART for six-months or more. Vascular assessments included flow-mediated dilation (FMD), aortic, radial and femoral arterial stiffness (cAIx, crPWV, cfPWV), and thigh and calf arterial compliance (Vmax50). Endothelial repair was indexed by endothelial progenitor cell colony forming units (EPC-CFU). Traditional CVD risk measures included blood pressure, central adiposity, lipids, insulin resistance (HOMA-IR), CRP and ASCVD score. Analyses controlled for demographics (age, sex, education), medications (antihypertensive, statin/fibrate, antipsychotic), and substance abuse (ASSIST). RESULTS: No group differences were observed in central adiposity, HOMA-IR, CRP, or ASCVD risk score. However, the ABC- group displayed greater dyslipidemia. The ABC+ group displayed no difference on FMD, cAIx, cfPWV or calf Vmax50 compared with other groups. When CD4 count and viral load were controlled, no additional differences between the ABC+ and ABC- groups emerged. Analyses of crPWV and thigh Vmax50 suggested supported by a trend toward lower EPC-CFU in the HIV+ groups than the HIV- group. CONCLUSIONS: Findings indicate that ABC treatment of 30-50 year-old PWH on stable ART is not likely to contribute in a robust way to higher CVD risk.

Airway and Pulmonary ß2-Adrenergic Vasodilatory Function in Current Smokers and Never Smokers.

BACKGROUND: Cigarette smoking has been associated with diminished vasodilatory function in the airway circulation. It is possible that cigarette smoking similarly affects the pulmonary circulation before resting pulmonary circulatory abnormalities become manifested. The aim of this study was to compare the acute effect of inhaled albuterol on airway and pulmonary hemodynamic function as an index of ß2-adrenoceptor-mediated vasodilation in smokers and never smokers. METHODS: In 30 adults, airway and pulmonary vascular function was assessed before and 15 min after albuterol inhalation (270 µg). From mean systemic arterial pressure, cardiac output, airway blood flow, and mean pulmonary arterial pressure, airway vascular resistance (AVR) and pulmonary vascular resistance (PVR) were derived. RESULTS: Albuterol induced a substantial drop in mean (± SE) PVR (-67.2% ± 5%), with no difference between groups. In contrast, the albuterol-induced decrease in AVR was significantly greater in never smokers than in smokers (-28.6% ± 3% vs -3.1% ± 6%; P < .02). CONCLUSIONS: These results are consistent with a dysfunction in a ß2-adrenergic signaling pathway mediating vasorelaxation in the airway circulation of current smokers. The vasodilatory deficit in the airway circulation but not in the pulmonary circulation could be related to local differences in the impact of cigarette smoke on the vascular endothelium.

Allogeneic Mesenchymal Stem Cells Restore Endothelial Function in Heart Failure by Stimulating Endothelial Progenitor Cells.

BACKGROUND: Endothelial dysfunction, characterized by diminished endothelial progenitor cell (EPC) function and flow-mediated vasodilation (FMD), is a clinically significant feature of heart failure (HF). Mesenchymal stem cells (MSCs), which have pro-angiogenic properties, have the potential to restore endothelial function. Accordingly, we tested the hypothesis that MSCs increase EPC function and restore flow-mediated vasodilation (FMD). METHODS: Idiopathic dilated and ischemic cardiomyopathy patients were randomly assigned to receive autologous (n = 7) or allogeneic (n = 15) MSCs. We assessed EPC-colony forming units (EPC-CFUs), FMD, and circulating levels of vascular endothelial growth factor (VEGF) in patients before and three months after MSC transendocardial injection (n = 22) and in healthy controls (n = 10). FINDINGS: EPC-colony forming units (CFUs) were markedly reduced in HF compared to healthy controls (4 ± 3 vs. 25 ± 16 CFUs, P < 0.0001). Similarly, FMD% was impaired in HF (5.6 ± 3.2% vs. 9.0 ± 3.3%, P = 0.01). Allogeneic, but not autologous, MSCs improved endothelial function three months after treatment (Δ10 ± 5 vs. Δ1 ± 3 CFUs, P = 0.0067; Δ3.7 ± 3% vs. Δ-0.46 ± 3% FMD, P = 0.005). Patients who received allogeneic MSCs had a reduction in serum VEGF levels three months after treatment, while patients who received autologous MSCs had an increase (P = 0.0012), and these changes correlated with the change in EPC-CFUs (P < 0.0001). Lastly, human umbilical vein endothelial cells (HUVECs) with impaired vasculogenesis due to pharmacologic nitric oxide synthase inhibition, were rescued by allogeneic MSC conditioned medium (P = 0.006). INTERPRETATION: These findings reveal a novel mechanism whereby allogeneic, but not autologous, MSC administration results in the proliferation of functional EPCs and improvement in vascular reactivity, which in turn restores endothelial function towards normal in patients with HF. These findings have significant clinical and biological implications for the use of MSCs in HF and other disorders associated with endothelial dysfunction.

Airway vascular endothelial function in healthy smokers without systemic endothelial dysfunction.

BACKGROUND: Cigarette smoking can lead to systemic endothelial dysfunction. Since the airway circulation is exposed to a high concentration of cigarette smoke constituents, we reasoned that airway vascular endothelial dysfunction could be present in healthy smokers without systemic endothelial dysfunction. OBJECTIVES: The purpose of this study was to compare airway and systemic endothelial function and measure markers of systemic inflammation in lung-healthy current smokers. Since endothelial dysfunction in smokers has been related to systemic inflammation, we also investigated its response to an inhaled glucocorticosteroid (ICS). METHODS: Fifteen healthy, current smokers and 17 healthy, lifetime nonsmokers were enrolled. Smokers were randomly assigned to 3-week treatments with inhaled fluticasone propionate or placebo in a crossover design. Vascular endothelial function was assessed in the airway by the airway blood-flow response to inhaled albuterol (ΔQaw) and in the extrapulmonary circulation by brachial arterial flow-mediated vasodilation (FMD). Venous blood was collected for C-reactive protein and IL-6. RESULTS: Baseline parameters did not differ between groups except for ΔQaw, which was greater in nonsmokers (45% ± 12%) than smokers (1% ± 12%) (P = .001). In the smokers, ICS treatment increased Qaw to 41% ± 7% (P < .001), but had no effect on FMD or inflammatory markers. There was an inverse relationship between baseline and ICS-induced changes in ΔQaw. CONCLUSIONS: Healthy smokers with no signs of systemic inflammation or endothelial dysfunction display impaired airway vascular endothelial function, possibly preceding systemic endothelial dysfunction. Airway endothelial function was restored with an ICS, and the response was directly related to the severity of endothelial dysfunction.

Chronic fatigue syndrome: illness severity, sedentary lifestyle, blood volume and evidence of diminished cardiac function.

The study examined whether deficits in cardiac output and blood volume in a CFS (chronic fatigue syndrome) cohort were present and linked to illness severity and sedentary lifestyle. Follow-up analyses assessed whether differences in cardiac output levels between CFS and control groups were corrected by controlling for cardiac contractility and TBV (total blood volume). The 146 participants were subdivided into two CFS groups based on symptom severity data, severe (n=30) and non-severe (n=26), and two healthy non-CFS control groups based on physical activity, sedentary (n=58) and non-sedentary (n=32). Controls were matched to CFS participants using age, gender, ethnicity and body mass. Echocardiographic measures indicated that the severe CFS participants had 10.2% lower cardiac volume (i.e. stroke index and end-diastolic volume) and 25.1% lower contractility (velocity of circumferential shortening corrected by heart rate) than the control groups. Dual tag blood volume assessments indicated that the CFS groups had lower TBV, PV (plasma volume) and RBCV (red blood cell volume) than control groups. Of the CFS subjects with a TBV deficit (i.e. > or = 8% below ideal levels), the mean+/-S.D. percentage deficit in TBV, PV and RBCV were -15.4+/-4.0, -13.2+/-5.0 and -19.1+/-6.3% respectively. Lower cardiac volume levels in CFS were substantially corrected by controlling for prevailing TBV deficits, but were not affected by controlling for cardiac contractility levels. Analyses indicated that the TBV deficit explained 91-94% of the group differences in cardiac volume indices. Group differences in cardiac structure were offsetting and, hence, no differences emerged for left ventricular mass index. Therefore the findings indicate that lower cardiac volume levels, displayed primarily by subjects with severe CFS, were not linked to diminished cardiac contractility levels, but were probably a consequence of a co-morbid hypovolaemic condition. Further study is needed to address the extent to which the cardiac and blood volume alterations in CFS have physiological and clinical significance.