Brain Morphological Changes in COVID-19

The aim of the study was to identify the pathomorphology of brain damage in patients who died of COVID-19.

Material and methods. Autopsy reports and autopsy brain material of 17 deceased patients with premortem confirmed COVID-19 infection were analyzed. Fatal cases in which COVID-19 was the major cause of death were included in the study. Five people were diagnosed with cerebral infarction. Organ samples were taken for histological examination during autopsy. Sections were stained with hematoxylin and eosin and by Nissl to assess brain histopathology. To study the vascular basal membranes the PAS reaction was used, to detect fibrin in vessels phosphotungstic acid-hematoxylin (PTAH) staining was used, to determine DNA in nuclei sections were stained according to Feulgen, to detect RNA in neuronal nuclei and cytoplasm sections were stained with methyl green-pyronin. Immunohistochemical study of a neuronal marker, nuclear protein NeuN, was performed to assess neuronal damage.

Results. The signs of neuronal damage found in patients who died of COVID-19 included nonspecific changes of nerve cells (acute swelling, retrograde degeneration, karyolysis and cytolysis, ‘ghost' cells, neuronophagia and satellitosis) and signs of circulatory disorders (perivascular and pericellular edema, diapedesis, congested and engorged microvasculature).

Conclusion. Brain histopathological data indicate damage to the central nervous system in COVID-19 patients. Ischemic stroke in patients with COVID-19 is mostly caused by a combination of hypoxia resulting from respiratory failure and individual risk factors, including cerebrovascular atherosclerosis and hypertension.

1. World Health Organization. Coronavirus disease (COVID-19) pandemic. 2021. Feb. 8 [cited 2021 April.12]. https://www.who.int/emer-gencies/diseases/novel-coronavirus-2019

2. SamsonovaM.V., MikhalevaL.M., Zairatyants O.V., Varyasin V.V., By-kanovaA.V., Mishnev O. D., Berezovsky Yu. S., Tishkevich O. A., Gom-zikova E. A., Chernyaev A. L., Khovanskaya T.N. Lung pathology of COVID-19 in Moscow. Archive of Pathology = Arkhivpatologii. 2020; 82 (4): 32-40. [In Russ.]. DOI: 10.17116/patol20208204132

3. Remmelink M., De Mendonga R., D’Haene N., De Clercq S., Verocq C., Lebrun L., Lavis P, Racu M. L., Trepant A. L., Maris C., Rorive S., Gof-fard J. C., De Witte O., Peluso L., Vincent J. L., Decaestecker C., Taccone F. S., Salmon I. Unspecific post-mortem findings despite multiorgan viral spread in COVID-19 patients. Critical care. 2020; 24 (1): 495. DOI: 10.1186/s13054-020-03218-5

4. Sisniega D.C., Reynolds A.S. Severe Neurologic Complications of SARS-CoV-2. Curr Treat Options Neurol. 2021; 23 (5): 14. DOI: 10.1007/s11940-021-00669-1. PMID: 33814894; PMCID: PMC8009931

5. Harrison S.L., Fazio-Eynullayeva E., Lane DA., Underhill P, Lip G.Y.H. Higher Mortality of Ischaemic Stroke Patients Hospitalized with COVID-19 Compared to Historical Controls. Cerebrovasc Dis. 2021; 26: 1-6. DOI: 10.1159/000514137. PMID: 33774618

6. Desforges M., Le Coupanec A., Dubeau P, Bourgouin A., Lajoie L., Dube M., Talbot PJ. Human Coronaviruses and Other Respiratory Viruses: Underestimated Opportunistic Pathogens of the Central Nervous System? Viruses. 2019; 12 (1): 14. DOI: 10.3390/v12010014. PMID: 31861926; PMCID: PMC7020001

7. Hamming I., Timens W., Bulthuis M.L., Lely A.T., Navis G., van Goor H. Tissue distribution of ACE2 protein, the functional receptor for SARS coronavirus. A first step in understanding SARS pathogenesis. J. Pathol. 2004; 203 (2): 631-637. DOI: 10.1002/path.1570. PMID: 15141377; PMCID: PMC7167720

8. Buzhdygan T.P., DeOre B.J., Baldwin-Leclair A., Bullock T.A., McGary H.M., Khan J.A., Razmpour R., Hale J.F., Galie P.A., Potula R., Andrews A.M., Ramirez S.H. The SARS-CoV-2 spike protein alters barrier function in 2D static and 3D microfluidic in-vitro models of the human blood-brain barrier. Neurobiol Dis. 2020; 146: 105131. DOI: 10.1016/j.nbd.2020.105131. Epub 2020 Oct 11. PMID: 33053430; PMCID: PMC7547916.

9. Paniz-Mondolfi A., Bryce C., Grimes Z., Gordon R.E., Reidy J., Lednicky J., Sordillo E.M., Fowkes M. Central nervous system involvement by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). J Med Virol. 2020; 92 (7): 699-702. DOI: 10.1002/jmv.25915. PMID: 32314810; PMCID: PMC7264598.

10. Rhea E.M., Logsdon A.F., Hansen K.M., Williams L.M., Reed M.J., Baumann K.K., Holden S.J., Raber J., Banks W.A., Erickson M.A. The S1 protein of SARS-CoV-2 crosses the blood-brain barrier in mice. Nat Neurosci. 2021; 24 (3): 368-378. DOI: 10.1038/s41593-020-00771-8. PMID: 33328624.

11. Iterim guidelines «Prevention, diagnosis and treatment of new coronavirus infection (COVID-19)». Version 9 (26.10.2020). Access mode: https://static-0.minzdrav.gov.ru/system/attachments/attaches/000/052/548/original/%D0%9C%D0%A0_COVID-19_%28v.9%29.pdf [In Russ.]

12. Maury A., Lyoubi A., Peiffer-Smadja N., de Broucker T., Meppiel E. Neurological manifestations associated with SARS-CoV-2 and other co-ronaviruses: A narrative review for clinicians. Rev Neurol. 2021; 177 (1-2): 51-64. DOI: 10.1016/j.neurol.2020.10.001. PMID: 33446327; PMCID: PMC7832485.

13. Mukerji S.S., Solomon I.H. What can we learn from brain autopsies in COVID-19? Neurosci Lett. 2021; 742: 135528. DOI: 10.1016/j.ne-ulet.2020.135528. PMID: 33248159; PMCID: PMC7687409

14. Mcllwain D.L., Hoke V.B. The role of the cytoskeleton in cell body enlargement, increased nuclear eccentricity and chromatolysis in axo-tomized spinal motor neurons. BMC Neurosci. 2005; 6: 19. DOI: 10.1186/1471-2202-6-19. PMID: 15774011; PMCID: PMC1079867.

15. Brown G.C., Neher J.J. Microglial phagocytosis of live neurons. Nat. Rev. Neurosci. 2014; 15: 209-216. DOI: 10.1038/nrn3710.

16. Lively S., SchlichterL.C. Microglia responses to pro-inflammatory stimuli (LPS, IFNgamma+TNFalpha) and reprogramming by resolving cytokines (IL-4, IL-10) Front Cell Neurosci. 2018; 12: 215. DOI: 10.3389/fncel.2018.00215.

17. Chen X., Zhao B., Qu Y., Chen Y., Xiong J., Feng Y., Men D., Huang Q., Liu Y., Yang B., Ding J., Li F. Detectable Serum Severe Acute Respiratory Syndrome Coronavirus 2 Viral Load (RNAemia) Is Closely Correlated With Drastically Elevated Interleukin 6 Level in Critically Ill Patients With Coronavirus Disease 2019. Clin Infect Dis. 2020; 71 (8): 1937-1942. DOI: 10.1093/cid/ciaa449. PMID: 32301997; PMCID: PMC7184354.

18. Liu J., Li S., Liu J., Liang B., WangX., WangH., Li W., Tong Q., Yi J., Zhao L. Longitudinal characteristics of lymphocyte responses and cytokine profiles in the peripheral blood of SARS-CoV-2 infected patients. EBioMedicine. 2020; 55: 102763. DOI: 10.1016/j.ebiom.2020.102763.

19. Al-Dalahmah O., Thakur K.T., NordvigA.S., PrustM.L., Roth W., Lig-nelli A., Uhlemann A.C., Miller E.H., Kunnath-Velayudhan S., Del Portillo A., Liu Y., Hargus G., Teich A.F., Hickman R.A., Tanji K., Goldman J.E., FaustP.L., Canoll P. Neuronophagia and microglial nodules in a SARS-CoV-2 patient with cerebellar hemorrhage. Acta Neuropathol Commun. 2020; 8 (1): 147. DOI: 10.1186/s40478-020-01024-2. PMID: 32847628; PMCID: PMC7447601.

20. Alekseeva O.S., Guselnikova V.V., Beznin G.V., Korzhevsky D.E. Prospects of using the NeuN nuclear protein as an indicator of the functional state of nerve cells in vertebrates. Zhurnal evolyutsionnoj bio-khimii i fiziologii. 2015; 51 (5): 313-323 [In Russ.]. https://www.elibrary.ru/download/elibrary_28359537_60959756.pdf

21. Sommer C. Histology and Infarct Volume Determination in Rodent Models of Stroke. In: Dirnagl U. (ed.) Rodent models of stroke. New York, USA: Springer Science+Business Media LLC; 2016: 263-278.

22. Guselnikova V.V., Korzhevsky D.E. NeuN-neuronal nuclear antigen and marker of differentiation of nerve cells. Acta Naturae. 2015; 7 (2): 25: 46-51 [In Russ.]. https://www.elibrary.ru/download/elibrary_23555354_52689797.pdf

23. Ferrucci M., Biagioni F., Lenzi P., Gambardella S., Ferese R., Calierno M.T., Falleni A., Grimaldi A., Frati A., Esposito V, Limatola C., Fornai F. Rapamycin promotes differentiation increasing pIII-tubulin, NeuN, and NeuroD while suppressing nestin expression in glioblastoma cells. Oncotarget. 2017; 8 (18): 29574-29599. DOI: 10.18632/oncotarget.15906. PMID: 28418837; PMCID: PMC5444688

24. Rauniyar S., Shen Zh., Lei W., Gu J., Pengjin M., Yu R. Primary granulosa cell tumor of cerebellum: A rare case report. Interdisciplinary Neurosurgery 2021; 23:100992 DOI: 10.1016/j.inat.2020.100992.

25. Yoshikawa T., Akiyoshi Y., Susumu T., Tokado H., Fukuzaki K., Nagata R., SamukawaK., Iwao H., Kito Go. Ginsenoside Rb1 Reduces Neurodegeneration in the Peri-infarct Area of a Thromboembolic Stroke Model in Non-human Primates. Journal of Pharmacological Sciences. 2008; 107 (1): 32-40. DOI: 10.1254/jphs.FP0071297.

26. Luo S.Y Li R., Le Z.Y., Li Q.L., Chen Z.W. Anfibatide protects against rat cerebral ischemia/reperfusion injury via TLR4/JNK/caspase-3 pathway. Eur. J. Pharmacol. 2017; 807: 127-137. DOI: 10.1016/j.ejp-har.2017.04.002.. PMID: 28390871.