Avaliação da carga viral de SARS-CoV-2 após oligoterapia contra a região compreendida pela Transcriptional Regulatory Sequence (TRS)
Data
2022-11-10
Autores
Santos, Gabriela Vasconde dos 
Orientadores
Janini, Luiz Mário Ramos
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
A pandemia da COVID-19 tem sido um enorme desafio em saúde pública para o mundo todo. Ao longo dos últimos 2 anos, estima-se que 6,55 milhões de indivíduos tenham morrido devido à COVID-19, sobretudo nos EUA, Índia e Brasil. As manifestações clássicas dos casos graves da COVID-19 incluem sintomas aéreos superiores e angústia ao respirar. Internamente, é observado um quadro inflamatório e protrombótico intenso que leva à internação e dano tecidual pulmonar e renal que eventualmente culmina em óbito. As principais estratégias para evitar a doença consistem em medidas profiláticas não farmacológicas, com destaque para o uso de máscaras e distanciamento social, além de adoção a esquema vacinal. Uma vez contaminado, o paciente pode fazer uso de antinflamatórios corticoesteróides, imunobiológicos e medicamentos antivirais, todos com eficácia comprovada, porém, limitada. O SARS-CoV-2 é um coronavírus com semelhanças aos coronavírus responsáveis pela MERS e SARS – Suas Transcriptional Regulatory Sequences são altamente conservadas e representam um bom alvo terapêutico para atividade antiviral. Sendo assim, o objetivo deste trabalho foi desenhar e selecionar oligonucleotídeos capazes de alinhar com a TRS do SARS-CoV-2 e avaliar a atividade antiviral e citotoxicidade destes em células Vero E6. Os ensaios realizados demonstraram atividade antiviral de alguns oligonucleotídeos construídos, mesmo em concentrações baixas (a partir de 15.62 nM). O mesmo oligonucleotídeo, em um ensaio para citotoxicidade, não diminuiu a viabilidade celular da cultura de células Vero E6 em uma concentração de até 1000 nM. O oligonucleotídeo ainda diminuiu as taxas de cópias virais e a replicação do vírus. Embora ensaios complementares sejam necessários, os dados aqui apresentados indicam que a TRS do SARS-CoV-2 pode ser um alvo terapêutico valioso, além de ser de suma importância para a biologia desse vírus.
The COVID-19 pandemic has been a huge public health challenge for the entire world. Over the past 2 years, an estimated 6.55 million individuals have died from COVID-19, mostly in the US, India, and Brazil. Classic manifestations of severe COVID-19 cases include upper air symptoms and distress when breathing. Internally, an intense inflammatory and prothrombotic condition is observed that leads to hospitalization and lung and kidney tissue damage that eventually culminates in death. The main strategies to avoid the disease consist of non-pharmacological prophylactic measures, with emphasis on the use of masks and social distancing, in addition to adopting a vaccination schedule. Once infected, the patient can make use of corticosteroid anti- inflammatory drugs, immunobiological and antiviral drugs, all with proven, but limited, efficacy. SARS-CoV-2 is a coronavirus with similarities to the coronaviruses responsible for MERS and SARS – Its Transcriptional Regulatory Sequences are highly conserved and represent a good therapeutic target for antiviral activity. Therefore, the objective of this work was to design and select oligonucleotides capable of aligning with the TRS of SARS-CoV-2 and to evaluate their antiviral activity and cytotoxicity in Vero E6 cells. The assays performed showed antiviral activity of some oligonucleotides constructed, even at low concentrations (from 15.62 nM). The same oligonucleotide, in an assay for cytotoxicity, did not decrease the cell viability of the Vero E6 cell culture at a concentration up to 1000 nM. The oligonucleotide also decreased viral copying rates and virus replication. Although complementary assays are needed, the data presented here indicate that the SARS-CoV-2 RRT may be a valuable therapeutic target, in addition to being of paramount importance for virus biology.
The COVID-19 pandemic has been a huge public health challenge for the entire world. Over the past 2 years, an estimated 6.55 million individuals have died from COVID-19, mostly in the US, India, and Brazil. Classic manifestations of severe COVID-19 cases include upper air symptoms and distress when breathing. Internally, an intense inflammatory and prothrombotic condition is observed that leads to hospitalization and lung and kidney tissue damage that eventually culminates in death. The main strategies to avoid the disease consist of non-pharmacological prophylactic measures, with emphasis on the use of masks and social distancing, in addition to adopting a vaccination schedule. Once infected, the patient can make use of corticosteroid anti- inflammatory drugs, immunobiological and antiviral drugs, all with proven, but limited, efficacy. SARS-CoV-2 is a coronavirus with similarities to the coronaviruses responsible for MERS and SARS – Its Transcriptional Regulatory Sequences are highly conserved and represent a good therapeutic target for antiviral activity. Therefore, the objective of this work was to design and select oligonucleotides capable of aligning with the TRS of SARS-CoV-2 and to evaluate their antiviral activity and cytotoxicity in Vero E6 cells. The assays performed showed antiviral activity of some oligonucleotides constructed, even at low concentrations (from 15.62 nM). The same oligonucleotide, in an assay for cytotoxicity, did not decrease the cell viability of the Vero E6 cell culture at a concentration up to 1000 nM. The oligonucleotide also decreased viral copying rates and virus replication. Although complementary assays are needed, the data presented here indicate that the SARS-CoV-2 RRT may be a valuable therapeutic target, in addition to being of paramount importance for virus biology.