That brain-controlling cat parasite? We’ve figured out how it works….

Science Daily plunges into the fun, fun research into how toxoplasmosis pulls your strings:

The parasite is Toxoplasma gondii, which has infected an estimated one in four Americans and even larger numbers worldwide. Not long after infecting a human, Toxoplasma parasites encounter the body’s immune response and retreat to a latent state, enveloped in hardy cysts that the body cannot remove.

Before entering that inactive state, however, the parasites appear to make significant changes in some of the brain’s most common, and critical cells, the researchers said. The team, lead by William Sullivan, Ph.D., professor of pharmacology and toxicology and of microbiology and immunology, reported two sets of related findings about those cells, called astrocytes, March 18 in the journal PLOS ONE.

Dr. Sullivan and his team evaluated the proteins in astrocyte cells and found 529 sites on 324 proteins where compounds called acetyl groups are added to proteins, creating a map called an “acetylome,” …

“We don’t know the impacts of these changes yet, but these discoveries could be particularly significant in understanding how the parasites persist in the brain and how this ‘rewiring’ could affect behavior in both rodents and humans,” Dr. Sullivan said.

In a separate article in the March 2015 issue of Scientific American Mind, Dr. Sullivan and IU School of Medicine colleague Gustavo Arrizabalaga, Ph.D, professor of pharmacology and toxicology and of microbiology and immunology, describe research by others dating back to the 1980s showing that rodents infected with Toxoplasma behave differently, including not only being unafraid of cat odors, but actually attracted to them.

One study found that infected men tend to be introverted, suspicious and rebellious, while infected women tended to be extraverted, trusting and obedient. Others have suggested an association with schizophrenia.

“The studies in humans have been relatively small and are correlative. In contrast, the behavioral changes seen in mice infected with Toxoplasma are much better characterized, although we still don’t know the mechanisms the parasite employs to alter host behavior,” Dr. Sullivan said. “But our analysis of the astrocyte acetylome changes could move us toward better understanding of Toxoplasma’s actions and the implications for behavioral impacts.”