Neta Francisca Idalina, Fernandes Amélia Carolina Lopes, Vale Adson José Martins, Pinheiro Francisco Irochima, Cobucci Ricardo Ney, Azevedo Eduardo Pereira de, Guzen Fausto Pierdoná
Postgraduate Program in Physiological Sciences, Department of Biomedical Sciences, Faculty of Health Sciences, State University of Rio Grande do Norte (UERN), Brazil.
Nurse Department, Nurse School, State University of Rio Grande do Norte (UERN), Mossoró, Brazil.
Curr Res Pharmacol Drug Discov. 2021;2:100035. doi: 10.1016/j.crphar.2021.100035. Epub 2021 Jun 5.
SARS-CoV-2 infects host cells mainly through the interaction between the virus's Spike protein and the viral receptors namely Angiotensin-Converting Enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2). Both are highly expressed in the gastrointestinal tract, in the nasal and bronchial epithelium, as well as in the type II alveolar epithelial cells. The aim of this review is to report the evidences from the scientific literature on the pathophysiology and the available treatments for olfactory-gustatory disorders in patients with COVID-19. The mechanisms involved in these disorders are still unclear and studies on specific therapies are scarce. However, it has been hypothesized that a decrease in the sensitivity of the sensory neurons as well as the co-expression of ACE2 and TMPRSS2 in the alveolar epithelial cells are the main causes of olfactory-gustatory disorders. The possible mechanisms described in the literature for changes in taste perception in patients with COVID-19 include olfactory disorders and a competitive activity of COVID-19 on ACE2 receptors in the taste buds. In addition, SARS-CoV-2 can bind to sialic acid receptors in the taste buds. In general, evidences show that there is no specific treatment for olfactory-taste disorders induced by SARS-CoV-2, even though some treatments have been used and have shown some promising results, such as olfactory training, intranasal application of sodium citrate and vitamin A, as well as systemic use of omega-3 and zinc. Corticosteroids have also been used as a pharmacological approach to treat patients with olfactory dysfunction with some contradictory results. The knowledge of the mechanisms by which SARS-CoV-2 influences the sensory systems and how effective therapies can treat the loss of smell and taste will have important implications on the understanding and clinical management of olfactory-taste disorders.
严重急性呼吸综合征冠状病毒2(SARS-CoV-2)主要通过病毒刺突蛋白与病毒受体(即血管紧张素转换酶2(ACE2)和跨膜丝氨酸蛋白酶2(TMPRSS2))之间的相互作用感染宿主细胞。二者在胃肠道、鼻和支气管上皮以及II型肺泡上皮细胞中均高表达。本综述的目的是报告科学文献中关于COVID-19患者嗅觉味觉障碍的病理生理学及现有治疗方法的证据。这些障碍所涉及的机制仍不清楚,针对特定疗法的研究也很匮乏。然而,据推测,感觉神经元敏感性降低以及肺泡上皮细胞中ACE2和TMPRSS2的共表达是嗅觉味觉障碍的主要原因。文献中描述的COVID-19患者味觉感知变化的可能机制包括嗅觉障碍以及COVID-19对味蕾中ACE2受体的竞争性作用。此外,SARS-CoV-2可与味蕾中的唾液酸受体结合。总体而言,证据表明,对于SARS-CoV-2引起的嗅觉味觉障碍尚无特异性治疗方法,尽管已使用了一些治疗方法并显示出一些有前景的结果,如嗅觉训练、鼻内应用柠檬酸钠和维生素A,以及全身使用ω-3和锌。皮质类固醇也已被用作治疗嗅觉功能障碍患者的药物方法,但结果存在一些矛盾。了解SARS-CoV-2影响感觉系统的机制以及有效疗法如何治疗嗅觉味觉丧失,将对嗅觉味觉障碍的理解和临床管理具有重要意义。