Randomized Trial of Anti-inflammatory Medications and Coronary Endothelial Dysfunction in Patients With Stable Coronary Disease.

Aims: Inflammation plays a critical role in the pathogenesis of coronary artery disease (CAD), however the impact of anti-inflammatory therapies to reduce those processes which promote atherosclerosis in CAD patients is unknown. We aimed to test the hypothesis that anti-inflammatory approaches improve impaired coronary endothelial function (CEF), a driver of coronary atherosclerosis, in stable CAD patients. Methods and Results: We performed a single-center, randomized, placebo-controlled, double-blinded trial to assess whether low dose methotrexate (MTX), low dose colchicine (LDC), and/or their combination (MTX+LDC), improves CEF using non-invasive MRI measures in patients with stable CAD (N = 94). The primary endpoint was the MRI-detected change in coronary cross-sectional area from rest to isometric handgrip exercise (IHE), a predominantly nitric oxide-dependent endothelial dependent stressor. Coronary and systemic endothelial endpoints, and serum inflammatory markers, were collected at baseline, 8 and 24 weeks. Anti-inflammatory study drugs were well-tolerated. There were no significant differences in any of the CEF parameters among the four groups (MTX, LDC, MTX+LDC, placebo) at 8 or 24 weeks. Serum markers of inflammation and systemic endothelial function measures were also not significantly different among the groups. Conclusion: This is the first study to examine the effects of the anti-inflammatory approaches using MTX, LDC, and/or the combination in stable CAD patients on CEF, a marker of vascular health and the primary endpoint of the study. Although these anti-inflammatory approaches were relatively well-tolerated, they did not improve coronary endothelial function in patients with stable CAD. Clinical Trial Registration: www.clinicaltrials.gov, identifier: NCT02366091.

A randomized, placebo-controlled, double-blinded clinical trial of colchicine to improve vascular health in people living with HIV.

OBJECTIVES: People living with HIV (PWH) experience an increased burden of coronary artery disease (CAD) believed to be related, in part, to an interplay of chronically increased inflammation and traditional risk factors. Recent trials suggest cardiovascular benefits of the anti-inflammatory, colchicine, in HIV-seronegative CAD patients. However, the impact of colchicine on impaired vascular health, as measured by coronary endothelial function (CEF), an independent contributor to CAD, has not been studied in PWH. We tested the hypothesis that colchicine improves vascular health in PWH. DESIGN: This was a randomized, placebo-controlled, double-blinded trial in 81 PWH to test whether low-dose colchicine (0.6 mg daily) improves CEF over 8-24 weeks. METHODS: Coronary and systemic endothelial function and serum inflammatory markers were measured at baseline, and at 8 and 24 weeks. The primary endpoint was CEF, measured as the change in coronary blood flow from rest to that during an isometric handgrip exercise, an endothelial-dependent stressor, measured with non-invasive MRI at 8 weeks. RESULTS: Colchicine was well tolerated and not associated with increased adverse events. However, there were no significant improvements in coronary or systemic endothelial function or reductions in serum inflammatory markers at 8 or 24 weeks with colchicine as compared to placebo. CONCLUSIONS: In PWH with no history of CAD, low-dose colchicine was well tolerated but did not improve impaired coronary endothelial function, a predictor of cardiovascular events. These findings suggest that this anti-inflammatory approach using colchicine in PWH does not improve vascular health, the central, early driver of coronary atherosclerosis.

Evolocumab, a PCSK9-Monoclonal Antibody, Rapidly Reverses Coronary Artery Endothelial Dysfunction in People Living With HIV and People With Dyslipidemia.

Background PCSK9 (proprotein convertase subtilisin/kexin type 9) is well recognized for its important role in cholesterol metabolism. Elevated levels are associated with increased cardiovascular risk and inhibition with PCSK9 antibodies (PCSK9i) lowers cardiovascular events in patients with coronary artery disease. PCSK9 levels are also elevated in people living with HIV (PLWH) and those with dyslipidemia. Because increased PCSK9 in PLWH is associated with impaired coronary endothelial function, a barometer of coronary vascular health, we tested the hypothesis that PCSK9i improves impaired coronary endothelial function in dyslipidemia without coronary artery disease and in PLWH with nearly optimal/above goal low-density lipoprotein cholesterol levels. Methods and Results We performed a single-center study in 19 PLWH and 11 with dyslipidemia to evaluate the effects of the PCSK9i evolocumab on coronary endothelial function using cine 3T MRI to noninvasively measure coronary endothelial function, assessed as the changes in coronary cross-sectional area and coronary blood flow from rest to that during isometric handgrip exercise, a known endothelial-dependent vasodilator. Before evolocumab, there was a decrease or no coronary vasodilation and no increase in coronary blood flow (the normal responses) to isometric handgrip exercise in either group. Following 6 weeks of evolocumab, 480 mg q4 weeks, the % cross-sectional area changes from rest to isometric handgrip exercise were +5.6±5.5% and +4.5±3.1% in the PLWH and dyslipidemia groups, respectively, both P<0.01 versus baseline. Improved cross-sectional area was paralleled by a significant coronary blood flow improvement in both groups. Conclusions To our knowledge, these data represent the first evidence that PCSK9 inhibition improves coronary artery health in PLWH and people with dyslipidemia. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03500302.

Coronary Endothelial Dysfunction Is Associated With Elevated Serum PCSK9 Levels in People With HIV Independent of Low-Density Lipoprotein Cholesterol.

Background HIV + people are at increased risk of coronary artery disease, but the responsible mechanisms are incompletely understood. Proprotein convertase subtilisin/kexin type 9 ( PCSK 9) is traditionally recognized for its importance in cholesterol metabolism; however, recent data suggest an additional, low-density lipoprotein receptor-independent adverse effect on endothelial cell inflammation and function. We tested the hypotheses that PCSK 9 levels are increased and that abnormal coronary endothelial function is related to PCSK 9 serum levels in HIV + individuals. Methods and Results Forty-eight HIV + participants receiving antiretroviral therapy with suppressed viral replication, without coronary artery disease, and 15 age- and low-density lipoprotein cholesterol-matched healthy HIV- subjects underwent magnetic resonance imaging to measure coronary endothelial function, quantified as percentage change in coronary artery cross-sectional area during isometric handgrip exercise, an endothelial-dependent stressor; and blood was obtained for serum PCSK 9 and systemic vascular biomarkers. Data are presented as mean±SD. Mean serum PCSK 9 was 65% higher in the HIV + subjects (302±146 ng/ mL ) than in the HIV - controls (183±52 ng/ mL , P<0.0001). Coronary endothelial function was significantly reduced in the HIV + versus HIV - subjects (percentage change in coronary artery cross-sectional area, 2.9±9.6% versus 11.1±3.7%; P<0.0001) and inversely related to PCSK 9 ( R=-0.51, P<0.0001). Markers of endothelial activation and injury, P-selectin and thrombomodulin, were also significantly increased in the HIV + subjects; and P-selectin was directly correlated with serum PCSK 9 ( R=0.31, P=0.0144). Conclusions Serum PCSK 9 levels are increased in treated HIV + individuals and are associated with abnormal coronary endothelial function, an established measure of vascular health.

Rapid identification of isometamidium-resistant stocks of Trypanosoma b. brucei by PCR-RFLP.

Analyses were made on the adenosine transporter-1 gene in Trypanosoma brucei (TbAT1), encoding a P2-like nucleoside transporter, from T. brucei brucei field stocks to investigate a possible link between the presence of mutations in this gene and isometamidium resistance. We have analysed the gene from 11 isometamidium-sensitive field stocks isolated from cattle in Uganda, two sensitive reference clones and two resistant reference clones. A sequence alignment showed that the isometamidium-sensitive T. b. brucei contained the wild-type sequence patterns. In contrast, the isometamidium-resistant T. b. brucei stocks showed the mutant-type sequence patterns with six point mutations that had previously been reported in a laboratory-derived arsenical-resistant T. brucei strain. To analyse the restriction fragment length polymorphism pattern of a fragment of TbAT1 (nucleotides 430-1108), the 677-bp polymerase chain reaction products from eight of the isometamidium-sensitive and two of the isometamidium-resistant T. b. brucei were subjected to digestion with Sfa NI. The results revealed two different banding patterns: the digest resulted in fragment sizes of 566 and 111 bp in the case of TbAT1 from isometamidium-sensitive stocks, whereas it produced fragment sizes of 435 and 242 bp in the case of TbAT1 from isometamidium-resistant stocks. Thus, the isometamidium-sensitive and isometamidium-resistant T. b. brucei could be successfully distinguished by digestion with the restriction endonuclease Sfa NI.

Application of field methods to assess isometamidium resistance of trypanosomes in cattle in western Ethiopia.

This study assessed the degree of isometamidium resistance of trypanosomes infecting cattle in the upper Didessa valley of western Ethiopia. An initial prevalence study was conducted to identify sites with a high risk of trypanosmosis in cattle. The trypanosome prevalence varied widely, with two sites, Kone (21.3%) and Village 1 settlement (15%) having a relatively high prevalence based on the phase-contrast buffy-coat technique (BCT). In the highest risk area, the Kone settlement, an isometamidium block treatment study was conducted from April to June 2001. A total of 300 cattle were included in this study, 100 from each of three villages (Cheleleki, Kolu and Burka). At day minus 14 of the study, all 300 cattle were treated with diminazene aceturate at 7 mg/kg body weight. Subsequently, these cattle were ear-tagged and randomly assigned into two groups, 50 controls and 50 for isometamidium treatment in each village. Fourteen days later (day 0), the 50 treatment cattle were given isometamidium chloride at 1 mg/kg body weight. Both groups of cattle were then examined for trypanosome parasites using BCT every 14 days until 84 days. The two indices used in assessing isometamidium resistance, namely the proportion of infections during an 8-week follow-up period and the ratio of mean hazards in an isometamidium treated versus untreated group, provided consistent results across the three villages. In Burka village, both indices demonstrated the presence of isometamidium resistance trypanosome infections while in Cheleleki and Kolu villages, both indices did not indicate significant levels of resistance. There were significant differences between the Kaplan-Meier survival estimates of the control and treatment groups in Cheleleki (P < 0.01) and Kolu (P < 0.05) but not in Burka (P > 0.05).