Abstract
The Coronavirus Disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) primarily targets respiratory cells, but emerging evidence shows neurological involvement, with the virus directly affecting neurons and glia. SARS-CoV-2 entry into a target cell requires co-expression of ACE2 (Angiotensin-converting enzyme-2) and TMPRSS2 (Trans membrane serine protease-2). Relevant literature on human neurological tissue is sparse and mostly focused on the olfactory areas. This prompted our study to map brain-wide expression of these entry proteins and assess age-related changes. The normal brain tissue samples were collected from cerebral cortex, hippocampus, basal ganglia, thalamus, hypothalamus, brain stem and cerebellum; and were divided into two groups - up to 40 years (n = 10) and above 40 years (n = 10). ACE2 and TMPRSS2 gene expression analysis was done using qRT-PCR and protein co-expression was seen by immunofluorescence. The ACE2 and TMPRSS2 gene expression was observed to be highest in hypothalamus and thalamus regions, respectively. Immunoreactivity for both ACE-2 and TMPRSS2 was observed in all examined brain regions, confirming the presence of these viral entry receptors. Co-localisation was maximum in hypothalamus. Our study did not find any trend related to different age groups. The expression of both these viral entry receptors suggests that normal human brain is susceptibility to SARS-CoV-2, perhaps which could be related to the cognitive and neurological impairment that occur in patients.
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References
Beckman D, Bonillas A, Diniz GB, Ott S, Roh JW, Elizaldi SR et al (2022) SARS-CoV-2 infects neurons and induces neuroinflammation in a non-human primate model of COVID-19. Cell Rep 41(5):111573. https://doi.org/10.1016/j.celrep.2022.111573
Bilinska K, Jakubowska P, Von Bartheld CS, Butowt R (2022) Expression of the SARS-CoV-2 entry proteins, ACE2 and TMPRSS2, in cells of the olfactory epithelium: identification of cell types and trends with age. ACS Chem Neurosci 11(11):1555–1562. https://doi.org/10.1021/acschemneuro.0c00210
Cho SM, White N, Premraj L, Battaglini D, Fanning J, Suen J et al (2023) Neurological manifestations of COVID-19 in adults and children. Brain 146(4):1648–1661. https://doi.org/10.1093/brain/awac332
Churchill NW, Roudaia E, Chen JJ, Gilboa A, Sekuler A, Ji X et al (2023) Effects of post-acute COVID-19 syndrome on the functional brain networks of non-hospitalized individuals. Front Neurol 14:531. https://doi.org/10.3389/fneur.2023.1136408
Collin J, Queen R, Zerti D, Dorgau B, Georgiou M, Djidrovski I (2021) Co-expression of SARS-CoV-2 entry genes in the superficial adult human conjunctival, limbal and corneal epithelium suggests an additional route of entry via the ocular surface. Ocul Surf 19:190–200. https://doi.org/10.1016/j.jtos.2020.05.013
Davidson AM, Wysocki J, Batlle D (2020) Interaction of SARS-CoV-2 and other coronavirus with ACE (angiotensin-converting enzyme)-2 as their main receptor: therapeutic implications. Hypertension 76(5):1339–1349. https://doi.org/10.1161/HYPERTENSIONAHA.120.15256
Deffner F, Scharr M, Klingenstein S, Klingenstein M, Milazzo A, Scherer S et al (2020) Histological evidence for the enteric nervous system and the choroid plexus as alternative routes of neuroinvasion by SARS-CoV2. Front Neuroanat 14:596439. https://doi.org/10.3389/fnana.2020.596439
Desai I, Manchanda R, Kumar N, Tiwari A, Kumar M (2021) Neurological manifestations of coronavirus disease 2019: exploring past to understand present. Neurol Sci 42(3):773–785. https://doi.org/10.1007/s10072-020-04964-8
Dong M, Zhang J, Ma X, Tan J, Chen L, Liu S, Xin Y, Zhuang L (2020) ACE2, TMPRSS2 distribution and extrapulmonary organ injury in patients with COVID-19. Biomed Pharmacother 131:110678. https://doi.org/10.1016/j.biopha.2020.110678
Emmi A, Tushevski A, Sinigaglia A, Barbon S, Sandre M, Stocco E et al (2023) ACE2 receptor and TMPRSS2 protein expression patterns in the human brainstem reveal anatomical regions potentially vulnerable to SARS-CoV-2 infection. ACS Chem Neurosci 14(11):2089–2097. https://doi.org/10.1021/acschemneuro.3c00101
Facondo P, Maltese V, Delbarba A, Pirola I, Rotondi M, Ferlin A, Cappelli C (2022) Case report: hypothalamic amenorrhea following COVID-19 infection and review of literatures. Front Endocrinol 13:840749. https://doi.org/10.3389/fendo.2022.840749
Fodoulian L, Tuberosa J, Rossier D, Boillat M, Kan C, Pauli V (2020) SARS-CoV-2 receptors and entry genes are expressed in the human olfactory neuroepithelium and brain. iScience 23(12):101839. https://doi.org/10.1016/j.isci.2020.101839
Garg S, Kim L, Whitaker M, O’Halloran A, Cummings C, Holstein R et al (2020) Hospitalization rates and characteristics of patients hospitalized with laboratory-confirmed coronavirus disease 2019—COVID-NET, 14 States, March 1–30, 2020. Morb Mortal Wkly Rep 69(15):458–464. https://doi.org/10.15585/mmwr.mm6915e3
Grisard HBDS, Schörner MA, Barazzetti FH, Wachter JK, Valmorbida M, Wagner G (2024) ACE2 and TMPRSS2 expression in patients before, during, and after SARS-CoV-2 infection. Front Cell Infect Microbiol 14:1355809. https://doi.org/10.3389/fcimb.2024.1355809
Hamming I, Cooper ME, Haagmans BL, Hooper NM, Korstanje R, Osterhaus AD et al (2007) The emerging role of ACE2 in physiology and disease. J Pathol 212(1):1–11. https://doi.org/10.1002/path.2162
Hasan MR, Ahmad MN, Dargham SR, Zayed H, Al Hashemi A, Ngwabi N (2021) Nasopharyngeal expression of angiotensin-converting enzyme 2 and transmembrane serine protease 2 in children within SARS-CoV-2-infected family clusters. Microbiol Spectr 9(3):e0078321. https://doi.org/10.1128/Spectrum.00783-21
Hikmet F, Méar L, Edvinsson Å, Micke P, Uhlén M, Lindskog C (2020) The protein expression profile of ACE2 in human tissues. Mol Syst Biol 16(7):e9610. https://doi.org/10.15252/msb.20209610
Huang N, Pérez P, Kato T, Mikami Y, Okuda K, Gilmore RC et al (2021) SARS-CoV-2 infection of the oral cavity and saliva. Nat Med 27(5):892–903. https://doi.org/10.1038/s41591-021-01296-8
Jackson CB, Farzan M, Chen B, Choe H (2022) Mechanisms of SARS-CoV-2 entry into cells. Nat Rev Mol Cell Biol 23(1):3–20. https://doi.org/10.1038/s41580-021-00418-x
Kaur M, Gupta T, Gupta M, Singla N, Kharbanda PS, Bansal YS et al (2023) Expressional study of permeability glycoprotein (P-gp) and Multidrug resistance protein 1 (MRP-1) in drug-resistant mesial temporal lobe Epilepsy. Basic Clin Neurosci 14(5):1–31. https://doi.org/10.32598/bcn.2021.2554.3
Li MY, Li L, Zhang Y, Wang XS (2020) Expression of the SARS-CoV-2 cell receptor gene ACE2 in a wide variety of human tissues. Infect Dis Poverty 9:45. https://doi.org/10.1186/s40249-020-00662-x
Li J, He X, Yuan Y, Zhang W, Li X, Zhang Y et al (2021) Meta-analysis investigating the relationship between clinical features, outcomes, and severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia. Am J Infect Control 49(1):82–89. https://doi.org/10.1016/j.ajic.2020.06.008
Lin L, Zeng F, Mai L, Gao M, Fang Z, Wu B et al (2023) Expression of ACE2, TMPRSS2, and SARS-CoV-2 nucleocapsid protein in gastrointestinal tissues from COVID-19 patients and association with gastrointestinal symptoms. Am J Med Sci 366(6):430–437. https://doi.org/10.1016/j.amjms.2023.08.014
Liu X, Yang N, Tang J, Liu S, Luo D, Duan Q, Wang X (2014) Downregulation of angiotensin-converting enzyme 2 by the neuraminidase protein of influenza A (H1N1) virus. Virus Res 24:185:64–71. https://doi.org/10.1016/j.virusres.2014.03.010
Lu Y, Zhu Q, Fox DM, Gao C, Stanley SA, Luo K (2022) SARS-CoV-2 down-regulates ACE2 through lysosomal degradation. Mol Biol Cell 33(14):ar147. https://doi.org/10.1016/j.virusres.2014.03.010
Malik JR, Acharya A, Avedissian SN, Byrareddy SN, Fletcher CV, Podany AT, Dyavar SR (2023) ACE-2, TMPRSS2, and Neuropilin-1 receptor expression on human brain astrocytes and pericytes and SARS-CoV-2 infection kinetics. Int J Mol Sci 24(10):8622. https://doi.org/10.3390/ijms24108622
Mencucci R, Favuzza E, Becatti M, Tani A, Mazzantini C, Vignapiano R (2021) Co-expression of the SARS-CoV-2 entry receptors ACE2 and TMPRSS2 in healthy human conjunctiva. Exp Eye Res 205:108527. https://doi.org/10.1016/j.exer.2021.108527
Mussa BM, Srivastava A, Verberne AJ (2021) COVID-19 and neurological impairment: hypothalamic circuits and beyond. Viruses 13(3):498. https://doi.org/10.3390/v13030498
Nampoothiri S, Sauve F, Ternier G, Fernandois D, Coelho C, Imbernon M (2020) The hypothalamus as a hub for SARS-CoV-2 brain infection and pathogenesis. bioRxiv 2020-06. https://doi.org/10.1101/2020.06.08.139329
Ong WY, Satish RL, Herr DR (2022) ACE2, Circumventricular organs and the hypothalamus, and COVID-19. NeuroMolecular Med 24(4):363–373. https://doi.org/10.1007/s12017-022-08706-1
Patel AB, Verma A (2020) COVID-19 and angiotensin-converting enzyme inhibitors and angiotensin receptor blockers: what is the evidence? JAMA 323(18):1769–1770. https://doi.org/10.1001/jama.2020.4812
Rahbar Saadat Y, Hosseiniyan Khatibi SM, Zununi Vahed S, Ardalan M (2021) Host serine proteases: a potential targeted therapy for COVID-19 and influenza. Front Mol Biosci 8:725528. https://doi.org/10.3389/fmolb.2021.725528
Rodrigues R, Costa de Oliveira S (2021) The impact of angiotensin-converting enzyme 2 (ACE2) expression levels in patients with comorbidities on COVID-19 severity: a comprehensive review. Microorganisms 9(8):1692. https://doi.org/10.3390/microorganisms9081692
Rolls ET (2019) The cingulate cortex and limbic systems for emotion, action, and memory. Brain Struct Funct 224(9):3001–3018. https://doi.org/10.1007/s00429-019-01945-2
Sakamoto A, Kawakami R, Kawai K, Gianatti A, Pellegrini D, Kutys R et al (2021) ACE2 (angiotensin-Converting enzyme 2) and TMPRSS2 (transmembrane serine protease 2) expression and localization of SARS-CoV-2 infection in the human heart. Arterioscler Thromb Vasc Biol 41(1):542–544. https://doi.org/10.1161/ATVBAHA.120.315229Epub 2020 Oct 22
Salamanna F, Maglio M, Landini MP, Fini M (2020) Body localization of ACE-2: on the trail of the keyhole of SARS-CoV-2. Front Med 7:594495. https://doi.org/10.3389/fmed.2020.594495
Santos RA, Sampaio WO, Alzamora AC, Motta-Santos D, Alenina N, Bader M, Campagnole-Santos MJ (2017) The ACE2/angiotensin-(1–7)/MAS axis of the renin-angiotensin system: focus on angiotensin-(1–7). Physiol Rev 98(1):505–553. https://doi.org/10.1152/physrev.00023.2016
Shaw R, Kim YK, Hua J (2020) Governance, technology and citizen behavior in pandemic: lessons from COVID-19 in East Asia. Prog Disaster Sci 6:100090. https://doi.org/10.1016/j.pdisas.2020.100090
Smith JC, Sausville EL, Girish V, Yuan ML, Vasudevan A, John KM, Sheltzer JM (2020) Cigarette smoke exposure and inflammatory signaling increase the expression of the SARS-CoV-2 receptor ACE2 in the respiratory tract. Dev cell 53(5):514–529e3. https://doi.org/10.1016/j.devcel.2020.05.012
Suryawanshi H, Morozov P, Muthukumar T, tenOever BR, Yamaji M, Williams Z, Tuschl T (2020) Cell-type-specific expression of renin-angiotensin-system components in the human body and its relevance to SARS-CoV-2 infection. BioRxiv 11:2020–2004. https://doi.org/10.1101/2020.04.11.034603
Tan BH, Liu JM, Gui Y, Wu S, Suo JL, Li YC (2021) Neurological involvement in the respiratory manifestations of COVID-19 patients. Aging 13(3):4713–4730. https://doi.org/10.18632/aging.202665
To KF, Lo AW (2004) Exploring the pathogenesis of severe acute respiratory syndrome (SARS): the tissue distribution of the coronavirus (SARS-CoV) and its putative receptor, angiotensin‐converting enzyme 2 (ACE2). J Pathol 203(3):740–743. https://doi.org/10.1002/path.1597
Vargas G, Geraldo LHM, Salomão NG, Paes MV, Lima FRS, Gomes FCA (2020) Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and glial cells: insights and perspectives. Brain Behav Immun Health 7:100127. https://doi.org/10.1016/j.bbih.2020.100127
Vieira C, Nery L, Martins L, Jabour L, Dias R, Simões e Silva AC (2021) Downregulation of membrane-bound angiotensin converting enzyme 2 (ACE2) receptor has a pivotal role in COVID-19 immunopathology. Curr Drug Targets 22(3):254–281. https://doi.org/10.1091/mbc.E22-02-0045
Vitalakumar D, Sharma A, Kumar A, Flora SJ (2021) Neurological manifestations in COVID-19 patients: a meta-analysis. ACS Chem Neurosci 12(15):2776–2797. https://doi.org/10.1021/acschemneuro.1c00353
Wais T, Hasan M, Rai V, Agrawal DK (2022) Gut-brain communication in COVID-19: molecular mechanisms, mediators, biomarkers, and therapeutics. Expert Rev Clin Immunol 18(9):947–960. https://doi.org/10.1080/1744666X.2022.2105697
Wilk-Sledziewska K, Sielatycki PJ, Uscinska N, Bujno E, Rosolowski M, Kakareko K et al (2022) The impact of cardiovascular risk factors on the course of COVID-19. J Clin Med 11(8):2250. https://doi.org/10.3390/jcm11082250
Williams TL, Strachan G, Macrae RG, Kuc RE, Nyimanu D, Paterson AL et al (2021) Differential expression in humans of the viral entry receptor ACE2 compared with the short delta ACE2 isoform lacking SARS-CoV-2 binding sites. Sci Rep 11(1):24336. https://doi.org/10.1038/s41598-021-03731-9
Winkler ES, Gilchuk P, Yu J, Bailey AL, Chen RE, Chong Z et al (2021) Human neutralizing antibodies against SARS-CoV-2 require intact fc effector functions for optimal therapeutic protection. Cell 184(7):1804–1820e16. https://doi.org/10.1016/j.cell.2021.02.026
Wu CR, Yin WC, Jiang Y, Xu HE (2022) Structure genomics of SARS-CoV-2 and its Omicron variant: drug design templates for COVID-19. Acta Pharmacol Sin 43(12):3021–3033. https://doi.org/10.1038/s41401-021-00851-w
Zhao Y, Zhao Z, Wang Y, Zhou Y, Ma Y, Zuo W (2020) Single-cell RNA expression profiling of ACE2, the receptor of SARS-CoV-2. Am J Respir Crit Care Med 202(5):756–759. https://doi.org/10.1164/rccm.202001-0179LE
Acknowledgements
The authors thank the subjects and their family members for the participation in this study. We thank DST-UT, Chandigarh for financial support.
Funding
The study was financially supported by the DST-UT, Chandigarh [No. S&T&RE/RP147/FY(21–22)/AA/10/2021/013-1020] through extramural research grant scheme. A.S. and R.B. were funded by CSIR, New Delhi.
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Conceptualization: TG; Sample and data collection: AR, RB, UJK, MK; Research facilities: TG; Data Analysis: TG, UJK, MK, AR, AB; Data Interpretation: TG, UJK, MK; Project administration: TG; Supervision: TG; Visualization: MK, UJK; Writing-original draft preparation: TG, MK, UJK; Writing-review and editing: TG, MK, UJK. All authors read and approved the final manuscript.
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Gupta, T., Kumar, M., Kaur, U.J. et al. Mapping ACE2 and TMPRSS2 co-expression in human brain tissue: implications for SARS-CoV-2 neurological manifestations. J. Neurovirol. (2024). https://doi.org/10.1007/s13365-024-01206-x
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DOI: https://doi.org/10.1007/s13365-024-01206-x