Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.4.24.B1 (
angiotensin-converting enzyme 2
)
1,025
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Background and Aims:
The angiotensin-(1-7)/
angiotensin-converting enzyme 2
/Mas receptor axis counter-regulates the detrimental effects of angiotensin II. Beneficial effects of angiotensin-(1-7), including anti-inflammation, oxidative stress reduction, and anti-thrombosis, have been reported. Previous studies documented that ramipril decreased
thrombin
generation in human hypertension and that the anti-thrombotic effects of captopril and losartan were angiotensin-(1-7)-dependent, suggesting an interaction between
thrombin
and angiotensin-(1-7). However, it is not clear whether angiotensin-(1-7) can alleviate the endothelial phenotypic changes induced by
thrombin
. We have previously documented cytoskeleton remodeling, cell adhesion, and cell migration as dominant altered phenotypes in
thrombin
-stimulated human aortic endothelial cells (HAECs). In this study, we investigated whether angiotensin-(1-7) can modulate
thrombin
-induced phenotypic changes. Furthermore, we investigated whether NAPDH oxidase 5 (Nox5)-produced reactive oxygen species (ROS) play a significant role in angiotensin-(1-7)-mediated phenotypic changes.
Methods:
HAECs were pretreated with 100 nM angiotensin-(1-7) for 1 h, followed by stimulation with 2 units/mL
thrombin
for different times. Immunofluorescent assay, monocyte adhesion assay, wound-healing assay, ROS assay, real-time PCR, Western blotting, and Nox5 siRNA transfection were conducted. HAECs were pretreated with the ROS scavenger N-acetylcysteine (NAC) to determine whether
thrombin
-induced phenotypic changes depended on ROS production.
Results:
Angiotensin-(1-7) prevented
thrombin
-induced actin cytoskeleton derangements, monocyte adhesion, and migratory impairment. Nox5 siRNA transfection confirmed that
thrombin
-induced Nox5 expression stimulated ROS production and increased HO-1/NQO-1/ICAM-1/VCAM-1 gene expression, all of which were decreased by angiotensin-(1-7). Phenotypic changes induced by
thrombin
were prevented by NAC pretreatment.
Conclusion:
Angiotensin-(1-7) prevents actin cytoskeleton derangement, monocyte adhesion, and migration impairment induced by
thrombin
via downregulation of ROS production. In addition,
thrombin
-induced Nox5 expression is involved in the production of ROS, and angiotensin-(1-7) decreases ROS through its inhibitory effect on Nox5 expression.
...
PMID:Angiotensin-(1-7) Inhibits Thrombin-Induced Endothelial Phenotypic Changes and Reactive Oxygen Species Production via NADPH Oxidase 5 Downregulation. 2937 91
The recent emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the ensuing global pandemic has presented a health emergency of unprecedented magnitude. Recent clinical data has highlighted that coronavirus disease 2019 (COVID-19) is associated with a significant risk of thrombotic complications ranging from microvascular thrombosis, venous thromboembolic disease, and stroke. Importantly, thrombotic complications are markers of severe COVID-19 and are associated with multiorgan failure and increased mortality. The evidence to date supports the concept that the thrombotic manifestations of severe COVID-19 are due to the ability of SARS-CoV-2 to invade endothelial cells via ACE-2 (
angiotensin-converting enzyme 2
), which is expressed on the endothelial cell surface. However, in patients with COVID-19 the subsequent endothelial inflammation, complement activation,
thrombin
generation, platelet, and leukocyte recruitment, and the initiation of innate and adaptive immune responses culminate in immunothrombosis, ultimately causing (micro)thrombotic complications, such as deep vein thrombosis, pulmonary embolism, and stroke. Accordingly, the activation of coagulation (eg, as measured with plasma D-dimer) and thrombocytopenia have emerged as prognostic markers in COVID-19. Given thrombotic complications are central determinants of the high mortality rate in COVID-19, strategies to prevent thrombosis are of critical importance. Several antithrombotic drugs have been proposed as potential therapies to prevent COVID-19-associated thrombosis, including heparin, FXII inhibitors, fibrinolytic drugs, nafamostat, and dipyridamole, many of which also possess pleiotropic anti-inflammatory or antiviral effects. The growing awareness and mechanistic understanding of the prothrombotic state of COVID-19 patients are driving efforts to more stringent diagnostic screening for thrombotic complications and to the early institution of antithrombotic drugs, for both the prevention and therapy of thrombotic complications. The shifting paradigm of diagnostic and treatment strategies holds significant promise to reduce the burden of thrombotic complications and ultimately improve the prognosis for patients with COVID-19.
...
PMID:The Emerging Threat of (Micro)Thrombosis in COVID-19 and Its Therapeutic Implications. 3258 14
The activated renin-angiotensin system induces a prothrombotic state resulting from the imbalance between coagulation and fibrinolysis. Angiotensin II is the central effector molecule of the activated renin-angiotensin system and is degraded by the
angiotensin-converting enzyme 2
to angiotensin (1-7). The novel coronavirus infection (classified as COVID-19) is caused by the new coronavirus SARS-CoV-2 and is characterized by an exaggerated inflammatory response that can lead to severe manifestations such as acute respiratory distress syndrome, sepsis, and death in a proportion of patients, mostly elderly patients with preexisting comorbidities. SARS-CoV-2 uses the
angiotensin-converting enzyme 2
receptor to enter the target cells, resulting in activation of the renin-angiotensin system. After downregulating the
angiotensin-converting enzyme 2
, the vasoconstrictor angiotensin II is increasingly produced and its counterregulating molecules angiotensin (1-7) reduced. Angiotensin II increases
thrombin
formation and impairs fibrinolysis. Elevated levels were strongly associated with viral load and lung injury in patients with severe COVID-19. Therefore, the complex clinical picture of patients with severe complications of COVID-19 is triggered by the various effects of highly expressed angiotensin II on vasculopathy, coagulopathy, and inflammation. Future treatment options should focus on blocking the thrombogenic and inflammatory properties of angiotensin II in COVID-19 patients.
...
PMID:Pathological Role of Angiotensin II in Severe COVID-19. 3260 67
COVID-19 has proven to be particularly challenging given the complex pathogenesis of SARS-CoV-2. Early data have demonstrated how the host response to this novel coronavirus leads to the proliferation of pro-inflammatory cytokines, massive endothelial damage, and generalized vascular manifestations. While SARS-CoV-2 primarily targets the upper and lower respiratory tract, other organ systems are also affected. SARS-CoV-2 relies on 2 host cell receptors for successful attachment:
angiotensin-converting enzyme 2
and transmembrane protease serine 2. Clinicopathologic reports have demonstrated associations between severe COVID-19 and viral coagulopathy, resulting in pulmonary embolism; venous, arterial, and microvascular thrombosis; lung endothelial injury; and associated thrombotic complications leading to acute respiratory distress syndrome. Viral coagulopathy is not novel given similar observations with SARS classic, including the consumption of platelets, generation of
thrombin
, and increased fibrin degradation product exhibiting overt disseminated intravascular coagulation-like syndrome. The specific mechanism(s) behind the thrombotic complications in COVID-19 patients has yet to be fully understood. Parenteral anticoagulants, such as heparin and low-molecular-weights heparins, are widely used in the management of COVID-19 patients. Beyond the primary (anticoagulant) effects of these agents, they may exhibit antiviral, anti-inflammatory, and cytoprotective effects. Direct oral anticoagulants and antiplatelet agents are also useful in the management of these patients. Tissue plasminogen activator and other fibrinolytic modalities may also be helpful in the overall management. Catheter-directed thrombolysis can be used in patients developing pulmonary embolism. Further investigations are required to understand the molecular and cellular mechanisms involved in the pathogenesis of COVID-19-associated thrombotic complications.
...
PMID:Viral Coagulopathy in Patients With COVID-19: Treatment and Care. 3268 49