tetano
Editor, Senior Moderator
Exp Neurol
. 2024 Jul 30:114908.
doi: 10.1016/j.expneurol.2024.114908. Online ahead of print. Neurotoxic effects of coronavirus: Potential implications in Alzheimer's onset and progression
Francesca Beretti[SUP] 1 [/SUP], Martina Gatti[SUP] 1 [/SUP], Francesco Ricchi[SUP] 2 [/SUP], Francesco Lipani[SUP] 2 [/SUP], Pietro Cortelli[SUP] 3 [/SUP], Claudio Cermelli[SUP] 2 [/SUP], Tullia Maraldi[SUP] 4 [/SUP]
Affiliations
The COVID-19, caused by SARS-CoV-2, first affects the respiratory tract but evidence is emerging that the virus, reaching the central nervous system (CNS), can lead to severe neurological disorders. In particular, CoV infection could cause an acceleration of the neurodegenerative process. On the other hand, patients diagnosed with Alzheimer's disease (AD) develop more serious forms of COVID-19 with worse relapses. Therefore, understanding the connection between the two pathologies, AD and infection by coronavirus, could help in the development of new therapeutic approaches to counter them. We used the SH-SY5Y cell line differentiated into neurons, as widely used in studies of AD if supplemented with exogenous fibrillary β-amyloid (Aβ). As a glial counterpart, human microglia (HMC3) and astrocytic (D54MG) cell lines were used to create co-cultures with neurons via transwell systems. In these experimental models, we generated infection with the Human Coronavirus OC43 (HCoV-OC43), a low-risk model of SARS-CoV-2. Our results suggest that the infection by HCoV-OC43 leads to a neurotoxic effect not depending on an already present event of Aβ deposition. Indeed, unlike microglia, neurons and even more astrocytes are susceptible to CoV infection and, although the infection does not show a cytotoxic effect in the neurons in the first few days, significant alterations at a biochemical and morphological level have been observed, suggesting that the neurons are reacting to a stressful condition, including the prodromal and neurodegenerative features of AD. Interestingly, the interaction of infected astrocytes with the neurons resulted in the manifestation of signs of neurodegeneration, such as amyloid-beta deposition. By using exogenous fibrillary Aβ, as an AD in vitro model, our data suggest that there is an aggravating effect both on the infection itself and on the neurological disease progression. In conclusion, the results of this study suggest a causal interplay between HCoV-OC43 and neurological diseases and demonstrate that the co-presence of different CNS cell populations is the necessary condition to study the pathogenic effects in vitro as a whole.
Keywords: Amyloid protein; Coronavirus; Neurodegeneration.
. 2024 Jul 30:114908.
doi: 10.1016/j.expneurol.2024.114908. Online ahead of print. Neurotoxic effects of coronavirus: Potential implications in Alzheimer's onset and progression
Francesca Beretti[SUP] 1 [/SUP], Martina Gatti[SUP] 1 [/SUP], Francesco Ricchi[SUP] 2 [/SUP], Francesco Lipani[SUP] 2 [/SUP], Pietro Cortelli[SUP] 3 [/SUP], Claudio Cermelli[SUP] 2 [/SUP], Tullia Maraldi[SUP] 4 [/SUP]
Affiliations
- PMID: 39089439
- DOI: 10.1016/j.expneurol.2024.114908
The COVID-19, caused by SARS-CoV-2, first affects the respiratory tract but evidence is emerging that the virus, reaching the central nervous system (CNS), can lead to severe neurological disorders. In particular, CoV infection could cause an acceleration of the neurodegenerative process. On the other hand, patients diagnosed with Alzheimer's disease (AD) develop more serious forms of COVID-19 with worse relapses. Therefore, understanding the connection between the two pathologies, AD and infection by coronavirus, could help in the development of new therapeutic approaches to counter them. We used the SH-SY5Y cell line differentiated into neurons, as widely used in studies of AD if supplemented with exogenous fibrillary β-amyloid (Aβ). As a glial counterpart, human microglia (HMC3) and astrocytic (D54MG) cell lines were used to create co-cultures with neurons via transwell systems. In these experimental models, we generated infection with the Human Coronavirus OC43 (HCoV-OC43), a low-risk model of SARS-CoV-2. Our results suggest that the infection by HCoV-OC43 leads to a neurotoxic effect not depending on an already present event of Aβ deposition. Indeed, unlike microglia, neurons and even more astrocytes are susceptible to CoV infection and, although the infection does not show a cytotoxic effect in the neurons in the first few days, significant alterations at a biochemical and morphological level have been observed, suggesting that the neurons are reacting to a stressful condition, including the prodromal and neurodegenerative features of AD. Interestingly, the interaction of infected astrocytes with the neurons resulted in the manifestation of signs of neurodegeneration, such as amyloid-beta deposition. By using exogenous fibrillary Aβ, as an AD in vitro model, our data suggest that there is an aggravating effect both on the infection itself and on the neurological disease progression. In conclusion, the results of this study suggest a causal interplay between HCoV-OC43 and neurological diseases and demonstrate that the co-presence of different CNS cell populations is the necessary condition to study the pathogenic effects in vitro as a whole.
Keywords: Amyloid protein; Coronavirus; Neurodegeneration.