Lourival Possani, emeritus researcher at the Institute of Biotechnology (IBT) of the National Autonomous University of Mexico, reported two discoveries developed in his lab, which recently obtained their respective patents.
Firstly, scorpion peptides (small proteins) that could constitute a new generation of antibiotics, targeting bacteria on which commercial drugs no longer work. And secondly, peptides that recognize a specific site in human lymphocytes that could help control the development of autoimmune diseases such as type 1 diabetes, psoriasis and rheumatoid arthritis.
“My specialty is biochemistry of scorpions’ venom, and by working with its components, we have discovered a number of proteins and peptides with significant pharmacological action,” said the scientist.
New Antibiotics
When studying the venom of scorpions, we found some peptides that function as antibiotic, i.e. preventing the development of certain colonies of bacteria or microorganisms harmful to humans, Possani said.
These peptides may represent a new generation antibiotics. Already known substances have to do with membranes assembly, which inhibit certain enzymes or act on bacteria’s nucleic material. However, because of their indiscriminate use, some strains have become resistant and antibiotics no longer take effect, which “has become a major public health problem,” he said.
The discovered peptides are not toxic; in fact, the scorpion uses them to defend itself from bacteria and saprophytic microorganisms that live in soil, their habitat. After studying them from the biochemical point of view, they were synthesized in Possani’s laboratory, “slightly modifying the structure”.
In collaboration with the National Institute of Public Health, owner of a large repertoire of drug-resistant bacteria in hospitals, tests were made and the peptides showed efficacy.
The discovered peptides have a certain specificity, some prefer the gram-positive bacteria, and others gram-negative bacteria, so they should be tested against different species of microorganisms. For example, some of them act on viruses or fungi. “We have tried with a long list of bacteria, including several strains of Escherichia coli.”
Currently, knowledge transference is being negotiated with a Mexican pharmaceutical interested in adding the peptides to conventional drugs, in order to increase efficiency and reduce high doses that often cause side effects.
Against Autoimmune Diseases
Possani said that along with his colleagues also discovered two peptides in the venom of a scorpion that is not dangerous to human: Vaejovis mexicanus smithi, which was collected “here, at UNAM, Cuernavaca campus.”
They are peptides that have a modulator activity of a very special potassium cellular channel, as it has been identified as a key element in the potential treatment of autoimmune diseases, such as above mentioned, psoriasis, rheumatoid arthritis or multiple sclerosis, and even organ rejection.
Thus, these peptides recognize a specific site in human lymphocytes and block Kv1.3 channels. The current theory is that if they get obstructed, the development of autoimmune diseases is inhibited.
The scientist said that instead of publishing their finding in a scientific journal, “we decided to write the work and patent it. We were a couple of years with the data in hand, but without disclosing it, because we wanted to get the register.” The patent previously granted in eight countries and/or regions are now obtained as geographical extensions of the same international application, in Eurasia, Australia and China.
For both projects, the arrival of the drugs to market will still take long time and will depend on the pharmaceutical in charge of making preclinical tests on animals and clinical tests phases 1, 2 and 3 in volunteers and patients, to demonstrate efficacy, dosages and safety.
Source: Agencia ID
