Research shows how protozoan toxoplasmosis can interfere with the functioning of the brain. The disease is associated with schizophrenia, depression and autism. Rats infected by the parasite that cause toxoplasmosis behave strangely, losing the natural fear of cats, the definitive hospitals of the protozoa that causes this disease. Research shows that when exposed to smell of feline urine, they seem to be attracted by the predator himself.
And just like in mice, the research shows that protozoa toxoplasmosis can also cause changes in human behavior. The parasite is associated with schizophrenia, depression, autism and even the greatest risk of involvement in traffic accidents.
A new investigation revealed how this protozoa can interfere with brain function. The scientists at Otto von Guericke University of Magdeburg and the Leibniz Institute of Neurobiology have discovered how this parasite influences the metabolism of the brain of its host.
Toxoplasmosis is caused by the prototype Toxoplasma gondii, which exists throughout the world. It infects birds and mammals, including humans. The parasite, however, can only be sexually reproduced in the digestive system of cats and felines, their definitive hosts.
The toxoplasmosis pathogen is eliminated along with cat feces. The transmission of the disease occurs through contact with contaminated feces or through the ingestion of contaminated food and water.
It is estimated that half of the entire adult population on the planet is infected with this protozoa, but in most cases, its presence goes unnoticed and has flu-like symptoms, such as fever, fatigue and muscle pain, as well as diarrhea. Toxoplasmosis is dangerous, however, for people with a weakened immune system and also during pregnancy.
Once infected, the parasite houses muscle tissues and brain and remains inactive for the rest of his life, which is called by doctors of occult infection.
According to the German study published in the Journal of Neuroinflammation, the parasite alters the molecular composition of the synapses, which are responsible for the transmission of brain signals.
"Toxoplasma gondii is absorbed by humans through digestion, enters the bloodstream and also migrates to the brain, entering nerve cells during the rest of their lives," said Karl-Heinz Smalla of the Special Laboratory of Molecular Biology Techniques from LIN.
In collaboration with the Helmholtz Center for Research on Infection, the researchers were able to demonstrate that the infection alters the amounts of 300 synaptic proteins in the rat brain.
The animals showed, in particular, fewer proteins near the excitatory receptors that release glutamate. At the same time, there is an increase in the proteins involved in immune responses.
"The malfunction of glutamatergic synapses is associated with depression, schizophrenia and autism. The components of the immune response are also related to these diseases," says Ildiko Rita Dunay, who worked in the study. "This suggests that immune reactions can cause changes in the synapse that can lead to neurological disorders," he adds.
The researchers also found that sulphadiazine, an antibiotic used to treat toxoplasmosis, can normalize metabolism in the brain of the infected mice. "All the proteins analyzed responsible for the transmission of the glutamatergic signal returned to normal and the inflammatory activity also decreased in a measurable way," said Björn Schott, a scientist who worked on research.
Deutsche Welle is the international radio station in Germany and produces independent media in 30 languages. Follow us on Facebook | Twitter | YouTube
| WhatsApp | Application | Instagram | Newsletter
Deutsche Welle is the international radio station in Germany and produces independent media in 30 languages.