Department of Medicine, University of Pennsylvania, Perelman Center for Advanced Medicine, 3400 Civic Center Boulevard,Philadelphia, PA 19104, USA.
Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania; 1157 BRB II/III, 421 Curie Boulevard, Philadelphia, PA 19104, USA.
J Biochem. 2021 Oct 11;170(2):299-306. doi: 10.1093/jb/mvab041.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus that has given rise to the devastating global pandemic. In most cases, SARS-CoV-2 infection results in the development of viral pneumonia and acute respiratory distress syndrome, known as 'coronavirus disease 2019' or COVID-19. Intriguingly, besides the respiratory tract, COVID-19 affects other organs and systems of the human body. COVID-19 patients with pre-existing cardiovascular disease have a higher risk of death, and SARS-CoV-2 infection itself may cause myocardial inflammation and injury. One possible explanation of such phenomena is the fact that SARS-CoV-2 utilizes angiotensin-converting enzyme 2 (ACE2) as the receptor required for viral entry. ACE2 is expressed in the cells of many organs, including the heart. ACE2 functions as a carboxypeptidase that can cleave several endogenous substrates, including angiotensin II, thus regulating blood pressure and vascular tone. It remains largely unknown if the SARS-CoV-2 infection alters the enzymatic properties of ACE2, thereby contributing to cardiovascular complications in patients with COVID-19. Here, we demonstrate that ACE2 cleavage of des-Arg9-bradykinin substrate analogue is markedly accelerated, while cleavage of angiotensin II analogue is minimally affected by the binding of spike protein. These findings may have implications for a better understanding of COVID-19 pathogenesis.
严重急性呼吸综合征冠状病毒 2(SARS-CoV-2)是一种新型冠状病毒,引发了这场毁灭性的全球大流行。在大多数情况下,SARS-CoV-2 感染会导致病毒性肺炎和急性呼吸窘迫综合征,即“2019 年冠状病毒病”或 COVID-19。有趣的是,COVID-19 除了影响呼吸道,还会影响人体的其他器官和系统。患有心血管疾病的 COVID-19 患者死亡风险更高,而 SARS-CoV-2 感染本身可能导致心肌炎症和损伤。出现这种现象的一种可能解释是,SARS-CoV-2 利用血管紧张素转化酶 2(ACE2)作为病毒进入所需的受体。ACE2 在包括心脏在内的许多器官的细胞中表达。ACE2 作为羧肽酶发挥作用,可切割包括血管紧张素 II 在内的几种内源性底物,从而调节血压和血管张力。目前尚不清楚 SARS-CoV-2 感染是否会改变 ACE2 的酶学特性,从而导致 COVID-19 患者发生心血管并发症。在这里,我们证明 ACE2 对无精氨酸 9-缓激肽底物类似物的切割明显加快,而 Spike 蛋白结合对血管紧张素 II 类似物的切割影响最小。这些发现可能对更好地理解 COVID-19 的发病机制具有重要意义。