In this Thursday’s edition (26) of the Medical Correspondent chart, of the New Day, neurosurgeon Fernando Gomes spoke about the study by the São Paulo State University (Unesp) that discovered a substance in a snake venom capable of containing the reproduction of the coronavirus.
Research by the Unesp Chemistry Institute in Araraquara, in the interior of São Paulo, identified a protein from the jararacuçu venom that was able to inhibit up to 75% of the virus’s reproduction capacity.
The doctor recalled that, in medicine, most treatments for diseases use substances from nature, including plant extracts and even snake venom.
“In São Paulo, there is the Ilha de Queimada Grande, in Itanhaém, where we have the jararaca-ilhoa, which has poison with the ability to control blood pressure and is used in medicines around the world,” said Gomes.
“[A proteína descoberta] it is capable of inhibiting virus replication by at least 75%, which is a great advantage, as we do not yet have a specific drug to treat the coronavirus”, he said.
“If there is a drug available that I can offer to the patient who is infected and it gives the immune system additional time to react, produce antibodies and cells can fight more efficiently, maybe we are facing a decisive substance in control of this disease”, pointed out Fernando Gomes.
Understand how the action of the protein piece works
When infecting a person, SARS-CoV-2, the virus that causes Covid-19, invades human cells and starts a process of multiplication. The numerous copies of the microorganism repeat the mechanism, with the aim of spreading. A drug capable of blocking this process can have a relevant impact on reducing damage to the body, such as damage to the tissues of the lungs and other organs of the respiratory system.
To verify the action of the protein piece (peptide), the researchers used laboratory-grown monkey cells. The experiments were divided into two groups: half of the cells received the peptide. After a period of two days, the scientists evaluated the viral replication capacity in the two groups of samples. The results showed that the molecule inhibited the multiplication of the virus in monkey cells by 75%.
“It is important to make it clear that it is not a poison molecule, it was inspired by the poison. Snake venom has several toxins. We took one of them and studied the activity of parts of this toxin. Our work synthesizes part of this toxin that was extracted from the venom of the jararacuçu, it is not the venom itself”, explains researcher Eduardo Maffud Cilli, a professor at the Institute of Chemistry and one of the authors of the study.
At USP’s São Carlos Institute of Physics (IFSC), the researchers reproduced one of the essential enzymes for viral multiplication, called PLPro. The molecule is needed to process the virus enzymes and assemble a mature viral particle, which is part of the replication process.
“We managed to produce this enzyme in the laboratory and tested the inhibition of the molecule in it. We saw that the molecule was able to inhibit the enzyme’s action. This is one of the molecule’s mechanisms of action on the virus. We need to assess whether there are others”, said Eduardo.
Tests of the action of the peptide against the new coronavirus were conducted at the Institute of Biomedical Sciences (ICB) at USP, in São Paulo, where a sample of the coronavirus is isolated. According to Eduardo, the next steps in the research include the pre-clinical phase, which involves studying the effectiveness of the molecule in the treatment of animals infected with the virus.
“With these results, we are going to start testing on human cells, especially lung cells, an organ that the virus mainly attacks. We will also check whether the molecule acts directly on the virus or only on viral replication. Depending on the results, we will go on to in vivo studies, which is to test the molecules in guinea pigs”, he concludes.
(*With information from Raphael Florêncio and Lucas Rocha, from CNN, in São Paulo)