Neutrophils,macrophages,CD3^(+),CD4^(+),and CD8^(+)T lymphocytes expressμ-,δ-,andκ-opioid receptors(ORs)with varying affinities for opioids.Mast cells express the atypical OR Mas-related G-protein-coupled receptor ...Neutrophils,macrophages,CD3^(+),CD4^(+),and CD8^(+)T lymphocytes expressμ-,δ-,andκ-opioid receptors(ORs)with varying affinities for opioids.Mast cells express the atypical OR Mas-related G-protein-coupled receptor X2(MRGPRX2),which has a low affinity for morphine.Neutrophils and macrophages can synthesize and release endogenous opioid peptides.Activation of ORs enhances the synthesis of proinflammatory cytokines and the production of reactive oxygen species(ROS)in unstimulated leukocytes.Conversely,OR activation reduces proinflammatory cytokine synthesis in stimulated neutrophils and macrophages.Morphine inhibits Toll-like receptor 4(TLR4)expression in macrophages,thereby attenuating inflammation,whereas methadone induces ROS production in mast cells through TLR4 activation.Stimulation of TLR4 triggersβ-endorphin synthesis in macrophages.The production of proinflammatory cytokines and ROS contributes to cardiac reperfusion injury.Importantly,activation ofκ1-andμ-ORs suppresses proinflammatory cytokine production by leukocytes,thereby mitigating inflammatory injury to the heart and other organs.展开更多
The analysis of experimental data demonstrates that platelets and neutrophils are involved in the no-reflow phenomenon,also known as microvascular obstruction(MVO).However,studies performed in the isolated perfused he...The analysis of experimental data demonstrates that platelets and neutrophils are involved in the no-reflow phenomenon,also known as microvascular obstruction(MVO).However,studies performed in the isolated perfused hearts subjected to ischemia/reperfusion(I/R)do not suggest the involvement of microembolization and microthrombi in this phenomenon.The intracoronary administration of alteplase has been found to have no effect on the occurrence of MVO in patients with acute myocardial infarction.Consequently,the major events preceding the appearance of MVO in coronary arteries are independent of microthrombi,platelets,and neutrophils.Endothelial cells appear to be the target where ischemia can disrupt the endothelium-dependent vasodilation of coronary arteries.However,reperfusion triggers more pronounced damage,possibly mediated by pyroptosis.MVO and intra-myocardial hemorrhage contribute to the adverse post-infarction myocardial remodeling.Therefore,pharmacological agents used to treat MVO should prevent endothelial injury and induce relaxation of smooth muscles.Ischemic conditioning protocols have been shown to prevent MVO,with L-type Ca2+channel blockers appearing the most effective in treating MVO.展开更多
The acute myocardial infarction(AMI)and sudden cardiac death(SCD),both associated with acute cardiac ischemia,are one of the leading causes of adult death in economically developed countries.The development of new app...The acute myocardial infarction(AMI)and sudden cardiac death(SCD),both associated with acute cardiac ischemia,are one of the leading causes of adult death in economically developed countries.The development of new approaches for the treatment and prevention of AMI and SCD remains the highest priority for medicine.A study on the cardiovascular effects of chronic hypoxia(CH)may contribute to the development of these methods.Chronic hypoxia exerts both positive and adverse effects.The positive effects are the infarct-reducing,vasoprotective,and antiarrhythmic effects,which can lead to the improvement of cardiac contractility in reperfusion.The adverse effects are pulmonary hypertension and right ventricular hypertrophy.This review presents a comprehensive overview of how CH enhances cardiac tolerance to ischemia/reperfusion.It is an in-depth analysis of the published data on the underlying mechanisms,which can lead to future development of the cardioprotective effect of CH.A better understanding of the CH-activated protective signaling pathways may contribute to new therapeutic approaches in an increase of cardiac tolerance to ischemia/reperfusion.展开更多
基金supported by the Russian Science Foundation(Grant No.23-65-10017 to B.K.K.and M.K.)The Ministry of Science and Higher Education of the Russian Federation(Grant No.122020300042-4 to L.N.M.)supported the preparation of the minichapter titled"Opioids reduce inflammatory injury of the heart".
文摘Neutrophils,macrophages,CD3^(+),CD4^(+),and CD8^(+)T lymphocytes expressμ-,δ-,andκ-opioid receptors(ORs)with varying affinities for opioids.Mast cells express the atypical OR Mas-related G-protein-coupled receptor X2(MRGPRX2),which has a low affinity for morphine.Neutrophils and macrophages can synthesize and release endogenous opioid peptides.Activation of ORs enhances the synthesis of proinflammatory cytokines and the production of reactive oxygen species(ROS)in unstimulated leukocytes.Conversely,OR activation reduces proinflammatory cytokine synthesis in stimulated neutrophils and macrophages.Morphine inhibits Toll-like receptor 4(TLR4)expression in macrophages,thereby attenuating inflammation,whereas methadone induces ROS production in mast cells through TLR4 activation.Stimulation of TLR4 triggersβ-endorphin synthesis in macrophages.The production of proinflammatory cytokines and ROS contributes to cardiac reperfusion injury.Importantly,activation ofκ1-andμ-ORs suppresses proinflammatory cytokine production by leukocytes,thereby mitigating inflammatory injury to the heart and other organs.
基金supported by the Russian Science Foundation(Grant No.23-65-10017)The mini-chapter on treatment of MVO was supported by state assignment 122020300042-4.
文摘The analysis of experimental data demonstrates that platelets and neutrophils are involved in the no-reflow phenomenon,also known as microvascular obstruction(MVO).However,studies performed in the isolated perfused hearts subjected to ischemia/reperfusion(I/R)do not suggest the involvement of microembolization and microthrombi in this phenomenon.The intracoronary administration of alteplase has been found to have no effect on the occurrence of MVO in patients with acute myocardial infarction.Consequently,the major events preceding the appearance of MVO in coronary arteries are independent of microthrombi,platelets,and neutrophils.Endothelial cells appear to be the target where ischemia can disrupt the endothelium-dependent vasodilation of coronary arteries.However,reperfusion triggers more pronounced damage,possibly mediated by pyroptosis.MVO and intra-myocardial hemorrhage contribute to the adverse post-infarction myocardial remodeling.Therefore,pharmacological agents used to treat MVO should prevent endothelial injury and induce relaxation of smooth muscles.Ischemic conditioning protocols have been shown to prevent MVO,with L-type Ca2+channel blockers appearing the most effective in treating MVO.
基金supported by the Russian Science Foundation grant 22-15-00048The section dedicated to the role of kinases in the cardioprotective effect of CH is framed within the framework of state assignments 122020300042-4.
文摘The acute myocardial infarction(AMI)and sudden cardiac death(SCD),both associated with acute cardiac ischemia,are one of the leading causes of adult death in economically developed countries.The development of new approaches for the treatment and prevention of AMI and SCD remains the highest priority for medicine.A study on the cardiovascular effects of chronic hypoxia(CH)may contribute to the development of these methods.Chronic hypoxia exerts both positive and adverse effects.The positive effects are the infarct-reducing,vasoprotective,and antiarrhythmic effects,which can lead to the improvement of cardiac contractility in reperfusion.The adverse effects are pulmonary hypertension and right ventricular hypertrophy.This review presents a comprehensive overview of how CH enhances cardiac tolerance to ischemia/reperfusion.It is an in-depth analysis of the published data on the underlying mechanisms,which can lead to future development of the cardioprotective effect of CH.A better understanding of the CH-activated protective signaling pathways may contribute to new therapeutic approaches in an increase of cardiac tolerance to ischemia/reperfusion.
