ACE2, Circumventricular Organs and the Hypothalamus, and COVID-19. 2022

Wei-Yi Ong, and R L Satish, and Deron R Herr
Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore. antongwy@nus.edu.sg.

The SARS-CoV-2 virus gains entry to cells by binding to angiotensin-converting enzyme 2 (ACE2). Since circumventricular organs and parts of the hypothalamus lack a blood-brain barrier, and immunohistochemical studies demonstrate that ACE2 is highly expressed in circumventricular organs which are intimately connected to the hypothalamus, and the hypothalamus itself, these might be easy entry points for SARS-CoV-2 into the brain via the circulation. High ACE2 protein expression is found in the subfornical organ, area postrema, and the paraventricular nucleus of the hypothalamus (PVH). The subfornical organ and PVH are parts of a circuit to regulate osmolarity in the blood, through the secretion of anti-diuretic hormone into the posterior pituitary. The PVH is also the stress response centre in the brain. It controls not only pre-ganglionic sympathetic neurons, but is also a source of corticotropin-releasing hormone, that induces the secretion of adrenocorticotropic hormone from the anterior pituitary. It is proposed that the function of ACE2 in the circumventricular organs and the PVH could be diminished by binding with SARS-CoV-2, thus leading to a reduction in the ACE2/Ang (1-7)/Mas receptor (MasR) signalling axis, that modulates ACE/Ang II/AT1R signalling. This could result in increased presympathetic activity/neuroendocrine secretion from the PVH, and effects on the hypothalamic-pituitary-adrenal axis activity. Besides the bloodstream, the hypothalamus might also be affected by SARS-CoV-2 via transneuronal spread along the olfactory/limbic pathways. Exploring potential therapeutic pathways to prevent or attenuate neurological symptoms of COVID-19, including drugs which modulate ACE signalling, remains an important area of unmet medical need.

UI MeSH Term Description Entries
D007030 Hypothalamo-Hypophyseal System A collection of NEURONS, tracts of NERVE FIBERS, endocrine tissue, and blood vessels in the HYPOTHALAMUS and the PITUITARY GLAND. This hypothalamo-hypophyseal portal circulation provides the mechanism for hypothalamic neuroendocrine (HYPOTHALAMIC HORMONES) regulation of pituitary function and the release of various PITUITARY HORMONES into the systemic circulation to maintain HOMEOSTASIS. Hypothalamic Hypophyseal System,Hypothalamo-Pituitary-Adrenal Axis,Hypophyseal Portal System,Hypothalamic-Pituitary Unit,Hypothalamic Hypophyseal Systems,Hypothalamic Pituitary Unit,Hypothalamo Hypophyseal System,Hypothalamo Pituitary Adrenal Axis,Portal System, Hypophyseal
D007031 Hypothalamus Ventral part of the DIENCEPHALON extending from the region of the OPTIC CHIASM to the caudal border of the MAMMILLARY BODIES and forming the inferior and lateral walls of the THIRD VENTRICLE. Lamina Terminalis,Preoptico-Hypothalamic Area,Area, Preoptico-Hypothalamic,Areas, Preoptico-Hypothalamic,Preoptico Hypothalamic Area,Preoptico-Hypothalamic Areas
D010913 Pituitary-Adrenal System The interactions between the anterior pituitary and adrenal glands, in which corticotropin (ACTH) stimulates the adrenal cortex and adrenal cortical hormones suppress the production of corticotropin by the anterior pituitary. Pituitary Adrenal System,Pituitary-Adrenal Systems,System, Pituitary-Adrenal,Systems, Pituitary-Adrenal
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000085962 Angiotensin-Converting Enzyme 2 A transmembrane glycoprotein with an extracellular catalytic domain which functions as a carboxypeptidase. It cleaves a single C-terminal residue from a distinct range of substrates. The catalytic efficiency is 400-fold higher with ANGIOTENSIN II as a substrate than with ANGIOTENSIN I. Angiotensin-converting enzyme 2 is also is a functional receptor for the spike glycoprotein (SPIKE PROTEIN, CORONAVIRUS) of the CORONAVIRUSES SARS-COV, SARS-COV2, and HCOV-NL63. ACE-Related Carboxypeptidase,ACE2 Angiotensin-Converting Enzyme Protein 2,ACE2 Enzyme,ACE2 Protein,Angiotensin Converting Enzyme 2,Angiotensin-Converting Enzyme-Related Carboxypeptidase,ACE Related Carboxypeptidase,ACE2 Angiotensin Converting Enzyme Protein 2,Angiotensin Converting Enzyme Related Carboxypeptidase,Carboxypeptidase, ACE-Related,Carboxypeptidase, Angiotensin-Converting Enzyme-Related
D000086382 COVID-19 A viral disorder generally characterized by high FEVER; COUGH; DYSPNEA; CHILLS; PERSISTENT TREMOR; MUSCLE PAIN; HEADACHE; SORE THROAT; a new loss of taste and/or smell (see AGEUSIA and ANOSMIA) and other symptoms of a VIRAL PNEUMONIA. In severe cases, a myriad of coagulopathy associated symptoms often correlating with COVID-19 severity is seen (e.g., BLOOD COAGULATION; THROMBOSIS; ACUTE RESPIRATORY DISTRESS SYNDROME; SEIZURES; HEART ATTACK; STROKE; multiple CEREBRAL INFARCTIONS; KIDNEY FAILURE; catastrophic ANTIPHOSPHOLIPID ANTIBODY SYNDROME and/or DISSEMINATED INTRAVASCULAR COAGULATION). In younger patients, rare inflammatory syndromes are sometimes associated with COVID-19 (e.g., atypical KAWASAKI SYNDROME; TOXIC SHOCK SYNDROME; pediatric multisystem inflammatory disease; and CYTOKINE STORM SYNDROME). A coronavirus, SARS-CoV-2, in the genus BETACORONAVIRUS is the causative agent. 2019 Novel Coronavirus Disease,2019 Novel Coronavirus Infection,2019-nCoV Disease,2019-nCoV Infection,COVID-19 Pandemic,COVID-19 Pandemics,COVID-19 Virus Disease,COVID-19 Virus Infection,Coronavirus Disease 2019,Coronavirus Disease-19,SARS Coronavirus 2 Infection,SARS-CoV-2 Infection,Severe Acute Respiratory Syndrome Coronavirus 2 Infection,COVID19,2019 nCoV Disease,2019 nCoV Infection,2019-nCoV Diseases,2019-nCoV Infections,COVID 19,COVID 19 Pandemic,COVID 19 Virus Disease,COVID 19 Virus Infection,COVID-19 Virus Diseases,COVID-19 Virus Infections,Coronavirus Disease 19,Disease 2019, Coronavirus,Disease, 2019-nCoV,Disease, COVID-19 Virus,Infection, 2019-nCoV,Infection, COVID-19 Virus,Infection, SARS-CoV-2,Pandemic, COVID-19,SARS CoV 2 Infection,SARS-CoV-2 Infections,Virus Disease, COVID-19,Virus Infection, COVID-19
D000086402 SARS-CoV-2 A species of BETACORONAVIRUS causing atypical respiratory disease (COVID-19) in humans. The organism was first identified in 2019 in Wuhan, China. The natural host is the Chinese intermediate horseshoe bat, RHINOLOPHUS affinis. 2019 Novel Coronavirus,COVID-19 Virus,COVID19 Virus,Coronavirus Disease 2019 Virus,SARS Coronavirus 2,SARS-CoV-2 Virus,Severe Acute Respiratory Syndrome Coronavirus 2,Wuhan Coronavirus,Wuhan Seafood Market Pneumonia Virus,2019-nCoV,2019 Novel Coronaviruses,COVID 19 Virus,COVID-19 Viruses,COVID19 Viruses,Coronavirus 2, SARS,Coronavirus, 2019 Novel,Coronavirus, Wuhan,Novel Coronavirus, 2019,SARS CoV 2 Virus,SARS-CoV-2 Viruses,Virus, COVID-19,Virus, COVID19,Virus, SARS-CoV-2,Viruses, COVID19
D066280 Circumventricular Organs Highly vascularized and specialized tissues distributed principally along the midline of the VENTRICULAR SYSTEM from the FOREBRAIN to the HINDBRAIN. They are distinguished by their lack of normal BLOOD-BRAIN BARRIER and fenestrated capillaries and contain either neurosecretory neurons or chemoreceptors. Neurohemal Organ,Secretory Circumventricular Organs,Sensory Circumventricular Organs,Circumventricular Organ,Circumventricular Organ, Secretory,Circumventricular Organ, Sensory,Circumventricular Organs, Secretory,Circumventricular Organs, Sensory,Neurohemal Organs,Organ, Circumventricular,Organ, Neurohemal,Organ, Secretory Circumventricular,Organ, Sensory Circumventricular,Organs, Circumventricular,Organs, Neurohemal,Organs, Secretory Circumventricular,Organs, Sensory Circumventricular,Secretory Circumventricular Organ,Sensory Circumventricular Organ

Related Publications

Wei-Yi Ong, and R L Satish, and Deron R Herr
July 2001, Clinical and experimental pharmacology & physiology,
Wei-Yi Ong, and R L Satish, and Deron R Herr
September 2017, Histology and histopathology,
Wei-Yi Ong, and R L Satish, and Deron R Herr
November 1997, The American journal of physiology,
Wei-Yi Ong, and R L Satish, and Deron R Herr
January 2020, Cell death discovery,
Wei-Yi Ong, and R L Satish, and Deron R Herr
September 2020, Acta physiologica (Oxford, England),
Wei-Yi Ong, and R L Satish, and Deron R Herr
October 1996, Frontiers in neuroendocrinology,
Wei-Yi Ong, and R L Satish, and Deron R Herr
January 1992, Progress in brain research,
Wei-Yi Ong, and R L Satish, and Deron R Herr
January 1998, Progress in brain research,
Copied contents to your clipboard!