ticagrelor and Reperfusion-Injury

Atorvastatin and ticagrelor have been shown to prevent against tissue injury in animals. It is unclear if these beneficial effects are also detectable in humans. We studied the effect of high-dose atorvastatin combined with ticagrelor loading on endothelial dysfunction in a model of forearm vascular ischemia-reperfusion (IR) injury.. 32 healthy subjects (n=16 per group) were enrolled in this randomized, placebo-controlled, double-blinded trial. Forearm blood flow (FBF) measurements in response to increasing intra-arterial doses of the vasodilator acetylcholine (ACh; endothelium-dependent agonist) and glyceryltrinitrate (GTN; endothelium-independent) were performed before and after a cuff-induced 20min forearm ischemia, respectively. FBF reactivity was assessed prior to any pharmacological intervention and after 14days intake of 80mg atorvastatin once daily or placebo, followed by an oral loading dose of 180mg ticagrelor. In addition, lipoprotein parameters and platelet aggregation were evaluated.. Ticagrelor loading mitigated ischemia-induced endothelial dysfunction and in combination with repeated atorvastatin dosing the response to ACh during reperfusion was completely normalized (FBF ACh. Chronic atorvastatin treatment combined with ticagrelor loading prevents against endothelial dysfunction after acute forearm ischemia. Ticagrelor alone mitigated the impaired endothelium-dependent FBF response as compared to no pharmacological intervention.. URL: https://clinicaltrials.gov. Unique identifier: NCT02910778.

Topics: Acetylcholine; Adenosine; Adolescent; Adult; Atorvastatin; Dose-Response Relationship, Drug; Double-Blind Method; Drug Therapy, Combination; Endothelium, Vascular; Forearm; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Male; Purinergic P2Y Receptor Antagonists; Regional Blood Flow; Reperfusion Injury; Ticagrelor; Vasodilation; Young Adult

Animal data suggest that ticagrelor but not clopidogrel protects against tissue injury. It is unclear if this effect of ticagrelor is also detectable in humans. We studied the effect of ticagrelor and clopidogrel at standard clinical doses on endothelial dysfunction in an experimental model of forearm vascular ischaemia-reperfusion (IR) injury.. In a randomized, single-blinded trial, 24 subjects underwent forearm blood flow (FBF) measurements in response to the endothelium-dependent vasodilator acetylcholine (ACh) and to glyceryltrinitrate (GTN; endothelium-independent) before and after a 20 min forearm ischaemia. FBF reactivity was assessed after an oral loading dose of ticagrelor or clopidogrel and after 14 days of regular intake of maintenance doses of the study medicines. In addition, the effect on platelet inhibition was evaluated using multiple electrode aggregometry.. ACh-induced vasodilation was impaired during reperfusion and not completely normalized by acute or chronic treatment with ticagrelor or clopidogrel (post- vs. pre-ischaemia). However, ticagrelor mitigated endothelial dysfunction compared to clopidogrel after loading (FBF ACh. Our data indicate that ticagrelor treatment exerts a greater vascular salutary effect than clopidogrel during reperfusion after an acute vascular occlusion. IR-induced vascular injury cannot be prevented completely by administration of these antiplatelet agents at standard clinical doses.

Topics: Adenosine; Administration, Oral; Adolescent; Adult; Austria; Blood Flow Velocity; Clopidogrel; Drug Administration Schedule; Endothelium, Vascular; Forearm; Healthy Volunteers; Humans; Male; Platelet Aggregation; Platelet Aggregation Inhibitors; Prospective Studies; Regional Blood Flow; Reperfusion Injury; Single-Blind Method; Ticagrelor; Ticlopidine; Time Factors; Treatment Outcome; Vasodilation; Vasodilator Agents; Young Adult

Aside from being an antiplatelet, ample studies revealed the anti-ischemic cardioprotective effect of Ticagrelor (Tica) mediated via different mechanisms; however, its protective potential against renal ischemia reperfusion (I/R) has been rarely investigated, which is the aim of the current study. Animals were divided into sham, I/R (45 min/24 h) and I/R pretreated with Tica (30 mg/kg) for one week, after a pilot study using 30 and 150 mg/kg of Tica. The pre-administration of Tica (30 mg/kg) guarded against the harmful impact of I/R insult and improved renal histological structure and function validated by reducing cystatin-C, neutrophil gelatinase-associated lipocalin, interleukin-18 and the classical markers, blood urea nitrogen and creatinine. On the molecular level, Tica signified its anti-inflammatory capacity by inhibiting nuclear factor κB and tumor necrosis factor-α, while it enhanced the autophagy process evidenced by increasing the protein expression of Beclin-1 and microtubule-associated protein light chain 3 II and abating the lysosomal marker cathepsin-D. Besides, Tica augmented cell survival by inhibiting galectin-3 and caspase-3 activity. Additionally, Tica modulated the renin-angiotensin system (RAS), where it decreased angiotensin II and downregulated the gene expression of prorenin and endothelin-1

Topics: Acute Kidney Injury; Animals; Autophagy; Dose-Response Relationship, Drug; Drug Repositioning; Galectin 3; Inflammation; Kidney; Platelet Aggregation Inhibitors; Protective Agents; Rats; Receptor, Endothelin A; Renin; Renin-Angiotensin System; Reperfusion Injury; Ticagrelor

Ticagrelor is a recommended P2Y. Patients with a previous ACS were studied with flow mediated dilatation of the left brachial artery to determine the degree of endothelial ischemia-reperfusion injury before and after discontinuation of ticagrelor treatment, which had been continuous since 1 year. Each patient underwent 3 identical examinations. The first examination (Visit A) was at the end of ticagrelor treatment and the following 2 (Visit B and C) were after cessation of this treatment with an interval of 2 to 4 weeks.. Ischemia and reperfusion induced significant impairment of endothelial function at all 3 occasions (absolute decline in flow mediated dilatation 3.0% ± 0.7 at Visit A (. Chronic ticagrelor treatment in patients 1 year after an ACS does not protect against endothelial ischaemia-reperfusion injury. Nor is it associated with better basal endothelial function compared to after discontinuation of treatment.

Topics: Adult; Aged; Coronary Artery Disease; Female; Humans; Male; Middle Aged; Platelet Aggregation Inhibitors; Reperfusion Injury; Ticagrelor

Increasing studies showed that several anti-platelet drugs turned out to be a promising strategy for inflammatory response. In this study, we investigated the protective efficiency of pretreatment of indobufen or aspirin combined with clopidogrel or ticagrelor (IACT) on cerebral ischemic injury via NF-κB/NLRP3 pathway. Ischemia/reperfusion (I/R) injury was simulated in vivo by middle cerebral artery occlusion/reperfusion (MCAO/R) model, and rats were pretreated with indobufen and aspirin and their combinations with clopidogrel or ticagrelor respectively. The platelet aggregation, cerebral infarct size, water content, neurological impairment and LDH release were measured. The relative expression of inflammasome mediated pyroptosis was determined by ELISA, RT-PCR, Tunel, Immunofluorescence and Western blotting as appropriate. In vitro, I/R injury was simulated in PC12 cells using oxygen glucose deprivation/reperfusion (OGD/R) and Lipopolysaccharide (LPS) to induce pyroptosis. The effect of combinations were significantly greater than MCAO/R group on decreasing the platelet aggregation, infarct size, brain edema, LDH release and neurologic impairment. LPS aggravated I/R-induced PC12 cell injury, which was significantly suppressed by pretreatment of IACT and Bay11-7082. Mechanistically, IACT alleviated transcriptionally encoded IL-1β, IL-18 and NLRP3 via inhibiting nuclear transportation of NF-κB. Importantly, at protein level, NLRP3, Caspase-1, IL-18, IL-1β and GSDMD were significantly decreased in combination groups both in vivo and vitro. IACT reduce inflammasome mediated pyroptosis in MCAO/R rats and OGD/R PC12 cells through inhibiting NF-κB/NLRP3 signaling pathway, which suggests that drug combination is a protective strategy with clinical potential against I/R-induced injury. Graphical abstract.

Topics: Animals; Aspirin; Brain Ischemia; Clopidogrel; Inflammasomes; Ischemic Stroke; Isoindoles; NF-kappa B; NLR Family, Pyrin Domain-Containing 3 Protein; Phenylbutyrates; Pyroptosis; Rats; Reperfusion Injury; Stroke; Ticagrelor

Topics: Acute Kidney Injury; Animals; Anti-Inflammatory Agents; Antioxidants; Apoptosis; Guanine Nucleotide Exchange Factors; Ischemia; Kidney Function Tests; Male; Purinergic P2Y Receptor Antagonists; rap1 GTP-Binding Proteins; Rats; Rats, Wistar; Renal Circulation; Reperfusion Injury; Signal Transduction; Ticagrelor

This study was conducted to reveal the possible protective effects of ticagrelor and enoxaparin pretreatment against ischemia-reperfusion (IR)-induced injury on the lung tissue of a rat model.. Wistar albino rats were randomly divided into 4 groups as follows: group-1 (control-sham), group-2 (control-saline+IR), group-3 (ticagrelor+IR), group-4 (enoxaparin+IR). Before the ischemic period, saline, ticagrelor, and enoxaparin were administered to the 2nd-4th groups, respectively. In these groups, IR injury was induced by clamping the aorta infrarenally for 2 h, followed by 4 h of reperfusion except group-1. After the rats were euthanized, the lungs were processed for histological examinations. Paraffin sections were stained with Haematoxylin&Eosin (H&E) for light microscopic observation. Apoptosis was evaluated by caspase-3 immunoreactivity. Data were statistically analyzed using the SPSS software.. In the lung sections stained with H&E, a normal histological structure was observed in group-1, whereas disorganized epithelial cells, hemorrhage, and inflammatory cell infiltration were seen in the alveolar wall in group-2. The histologic structure of the treatment groups was better than that of group-2. Caspase-3(+) apoptotic cells were noticeable in sections of group-2 and were lower in the treatment groups. In group-4, caspase-3 immunostaining was lower than in group-3. In group-2, apoptotic cells were significantly higher than in the other groups (p<0.001).. Based on the histological results, we suggested that both therapies ameliorated the detrimental effects of IR. Caspase-3 immunohistochemistry results also revealed that pre-treatment with enoxaparin gave better results in an IR-induced rat injury model. In further studies, other parameters such as ROS and inflammatory gene expressions should be evaluated for accurate results.

Topics: Animals; Aorta, Abdominal; Apoptosis; Caspase 3; Disease Models, Animal; Enoxaparin; Lung; Lung Injury; Male; Protective Agents; Random Allocation; Rats, Wistar; Reperfusion Injury; Ticagrelor

Ticagrelor is a direct acting and reversibly binding P2Y12 antagonist approved for the prevention of thromboembolic events. Its potential benefits in ischemic stroke have not been investigated sufficiently. Mice were subjected to 2 hours of transient middle cerebral artery occlusion (MCAO). Mice were orally treated with ticagrelor (10 or 30 mg/kg), aspirin (60 mg/kg), or vehicle at 3 and 24 hours before MCAO and 0 and 6 hours after reperfusion. The infarct volume and neurological deficits 22 hours after reperfusion were evaluated. Cerebral blood flow (CBF) within 24 hours after MCAO was monitored. We performed western blotting and in vitro analysis using oxygen-glucose deprivation (OGD) stress in human brain microvessel endothelial cells (HBMVECs) to investigate the protective effects of ticagrelor. Ticagrelor (30 mg/kg) improved neurological deficits, reduced the infarct volume, and improved CBF. It promoted the phosphorylation of endothelial nitric oxide synthase (eNOS) and extracellular signal-regulated kinase 1/2 (ERK1/2) during the early phase after reperfusion. Increased phosphorylation of eNOS and ERK1/2 were also observed in HBMVECs after OGD stress. Ticagrelor attenuate ischemia reperfusion injury possibly via phosphorylation of eNOS and ERK1/2 in endothelial cells. This suggests that ticagrelor has neuroprotective effects via mechanisms other than its antiplatelet action.

Topics: Animals; Brain Infarction; Brain Ischemia; Cerebrovascular Circulation; Disease Models, Animal; Humans; Infarction, Middle Cerebral Artery; Mice; Neuroprotective Agents; Nitric Oxide Synthase Type III; Phosphorylation; Purinergic P2Y Receptor Antagonists; Reperfusion Injury; Stroke; Ticagrelor