A physiological sequence called autophagy qualitatively determines cellular viability by removing protein aggregates and damaged cyto-plasmic constituents, and contributes significantly to the degree of myocardial isc...A physiological sequence called autophagy qualitatively determines cellular viability by removing protein aggregates and damaged cyto-plasmic constituents, and contributes significantly to the degree of myocardial ischemia-reperfusion （I/R） injury. This tightly orchestrated cata-bolic cellular‘housekeeping’ process provides cells with a new source of energy to adapt to stressful conditions. This process was first described as a pro-survival mechanism, but increasing evidence suggests that it can also lead to the demise of the cell. Autophagy has been implicated in the pathogenesis of multiple cardiac conditions including myocardial I/R injury. However, a debate persists as to whether autophagy acts as a protec-tive mechanism or contributes to the injurious effects of I/R injury in the heart. This controversy may stem from several factors including the va-riability in the experimental models and species, and the methodology used to assess autophagy. This review provides updated knowledge on the modulation and role of autophagy in isolated cardiac cells subjected to I/R, and the growing interest towards manipulating autophagy to increase the survival of cardiac myocytes under conditions of stress-most notably being I/R injury. Perturbation of this evolutionarily conserved intracellular cleansing autophagy mechanism, by targeted modulation through, among others, mammalian target of rapamycin （mTOR） inhibitors, adenosine monophosphate-activated protein kinase （AMPK） modulators, calcium lowering agents, resveratrol, longevinex, sirtuin activators, the proapoptotic gene Bnip3, IP3 and lysosome inhibitors, may confer resistance to heart cells against I/R induced cell death. Thus, therapeutic ma-nipulation of autophagy in the challenged myocardium may benefit post-infarction cardiac healing and remodeling.展开更多
Heart failure （HF）, a complex clinical syndrome due to structural or functional disorder of the heart, is a major global health issue, with a prevalence of over 5.8 million in the USA alone, and over 23 million worl...Heart failure （HF）, a complex clinical syndrome due to structural or functional disorder of the heart, is a major global health issue, with a prevalence of over 5.8 million in the USA alone, and over 23 million worldwide. As a leading cause of hospitalizations among patients aged 65 years or older, HF is a major consumer of healthcare resources, creating a substantial strain on the healthcare system. This paper discusses the epidemiology of HF, financial impact, and multifaceted predicaments in end-stage HF care. A search was conducted on the U.S National Library of Medicine website （www.pubmed.gov） using keywords such as end-stage heart failure, palliative care, ethical dilemmas. Despite the poor prognosis of HF （worse than that for many cancers）, many HF patients, caregivers, and clinicians are unaware of the poor prognosis. In addition, the unpredictable clinical trajectory of HF complicates the planning of end-of-life care, such as palliative care and hospice, leading to underutilization of such resources. In conclusion, ethical dilemmas in end-stage HF are numerous, embroiling not only the patient, but also the caregiver, healthcare team, and society.展开更多
文摘A physiological sequence called autophagy qualitatively determines cellular viability by removing protein aggregates and damaged cyto-plasmic constituents, and contributes significantly to the degree of myocardial ischemia-reperfusion （I/R） injury. This tightly orchestrated cata-bolic cellular‘housekeeping’ process provides cells with a new source of energy to adapt to stressful conditions. This process was first described as a pro-survival mechanism, but increasing evidence suggests that it can also lead to the demise of the cell. Autophagy has been implicated in the pathogenesis of multiple cardiac conditions including myocardial I/R injury. However, a debate persists as to whether autophagy acts as a protec-tive mechanism or contributes to the injurious effects of I/R injury in the heart. This controversy may stem from several factors including the va-riability in the experimental models and species, and the methodology used to assess autophagy. This review provides updated knowledge on the modulation and role of autophagy in isolated cardiac cells subjected to I/R, and the growing interest towards manipulating autophagy to increase the survival of cardiac myocytes under conditions of stress-most notably being I/R injury. Perturbation of this evolutionarily conserved intracellular cleansing autophagy mechanism, by targeted modulation through, among others, mammalian target of rapamycin （mTOR） inhibitors, adenosine monophosphate-activated protein kinase （AMPK） modulators, calcium lowering agents, resveratrol, longevinex, sirtuin activators, the proapoptotic gene Bnip3, IP3 and lysosome inhibitors, may confer resistance to heart cells against I/R induced cell death. Thus, therapeutic ma-nipulation of autophagy in the challenged myocardium may benefit post-infarction cardiac healing and remodeling.
文摘Heart failure （HF）, a complex clinical syndrome due to structural or functional disorder of the heart, is a major global health issue, with a prevalence of over 5.8 million in the USA alone, and over 23 million worldwide. As a leading cause of hospitalizations among patients aged 65 years or older, HF is a major consumer of healthcare resources, creating a substantial strain on the healthcare system. This paper discusses the epidemiology of HF, financial impact, and multifaceted predicaments in end-stage HF care. A search was conducted on the U.S National Library of Medicine website （www.pubmed.gov） using keywords such as end-stage heart failure, palliative care, ethical dilemmas. Despite the poor prognosis of HF （worse than that for many cancers）, many HF patients, caregivers, and clinicians are unaware of the poor prognosis. In addition, the unpredictable clinical trajectory of HF complicates the planning of end-of-life care, such as palliative care and hospice, leading to underutilization of such resources. In conclusion, ethical dilemmas in end-stage HF are numerous, embroiling not only the patient, but also the caregiver, healthcare team, and society.
