Infection with the obligate intracellular parasite, Toxoplasma gondii, leads to neuronal cysts in the brain for the lifetime of the host. Our lab has previously determined that chronic infection leads to loss of astrocytic glutamate transported, GLT-1, leading to neuronal excitotoxicity. GLT-1 can be regulated by neuronal derived extracellular vesicles (EVs). We wanted to determine if cyst infection of neurons altered EV production and content and if EVs derived from cyst-containing neurons changed astrocyte function. Our study found that Toxoplasma cyst infection decreased EV production by neurons and altered EV host protein and miRNA content. In addition, EVs from infected neurons contained parasite derived proteins including the secreted dense granule protein GRA7. Incubation of these EVs with astrocytes led to EV uptake, GRA7 localization to the nucleus, a decrease in GLT-1 expression, and changes in the transcriptional signature of astrocytes to a pro-inflammatory response. Finally, these changes in astrocytic gene expression could be seen in vivo following infection using scRNAseq. This study demonstrates that Toxoplasma cysts alter neuron-astrocyte communication bypassing traditional immune mechanisms of recognition and leading to changes in astrocyte function.
Citation: Tabaie EZ, Gao Z, Kachour N, Ulu A, Gomez S, Figueroa ZA, et al. (2025) PLoS Pathog 21: e1012733. https://doi.org/10.1371/journal.ppat.
Editor: Eric Y. Denkers, University of New Mexico—Albuquerque: The University of New Mexico, UNITED STATES OF AMERICA.
The smarter you are, the more your brain is in sync with its own secret rhythm, a new study has found.
When your brain works particularly hard, different regions of the brain sync up as they work together to perform tasks that require a higher cognitive load. This is called theta connectivity, and a new study has found that not only is it highly flexible, adapting quickly to changing situations, but better brain coordination strongly correlates with cognitive ability.
“Specific signals in the midfrontal brain region are better synchronized in people with higher cognitive ability – especially during demanding phases of reasoning,” says psychologist Anna-Lena Schubert of Johannes Gutenberg University Mainz in Germany.
When we hear the term “burnout”, most of us would think about working long hours, and the stress built up from our jobs and the people involved in them. However, a surprising new study suggests that only a minority of people with burnout actually think their symptoms are due to their work.
The research, which was led by a team from the Norwegian University of Science and Technology (NTNU), could challenge the conventional thinking about how people reach burnout, and how we might be able to protect against it.
Less than 30 percent of the people surveyed blamed their job as the primary reason they felt burnt out.
A new mobile crypto-stealing malware called SparkKitty was found in apps on Google Play and the Apple App Store, targeting Android and iOS devices.
The malware is a possible evolution of SparkCat, which Kaspersky discovered in January. SparkCat used optical character recognition (OCR) to steal cryptocurrency wallet recovery phrases from images saved on infected devices.
When installing crypto wallets, the installation process tells users to write down the wallet’s recovery phrase and store it in a secure, offline location.
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The King plot is a graphical technique used to analyze isotope shifts, variations in the energy levels of different isotopes (e.g., atoms of the same element that contain a different number of neutrons). This graphical tool has proved promising for separating effects explained by the SM from signals linked to new physics.
Researchers at Physikalisch-Technische Bundesanstalt, Max Planck Institute for Nuclear Physics, and ETH Zurich recently collected new measurements that tightened King plot-based constraints on the properties of a hypothetical particle that has not yet been observed, known as a Yukawa-type boson.