Description: Perhaps you have heard about Toxoplasmosis? It is a condition caused by a parasite that is carried by cats who catch wild birds and that can be picked up by humans when they clean the cats’ litter boxes and inhale some of the T. gondii parasite while doing so. Exposure among pregnant women can cause miscarriage, stillbirth or brain or eye damage in the developing fetus. That is why women who become pregnant are told to pass any litter box clearing duties they have had off to someone else. While you may have heard about that (it is one of the examples of prenatal teratogens I am others typically include in lectures on prenatal development) you may not have run across an explanation of how the T. gondii parasite effects the brain and immune system. It has been know for a while that the parasite reduced norepinephrine production in the brain and that it seems to suppress the immune system but how these are related has not been clear. The researchers whose work is discussed in the linked article have taken a large step towards clarifying how the effects of this parasite on the brain and immune system are related AND the results may suggest some power new things in relation to our understanding and treatment of schizophrenia, dementia and ADHD. Have a read through the linked article to see what this all might suggest.
Source: Parasite infection discovery could assist mental health treatments, Science News, ScienceDaily.
Date: November 16, 2020
So, the T. gondii parasite, once it gets into the brain, influences the norepinephrine system which is involved in regulating our body’s immune response. This linking of two previously opposing theories about how Toxoplasmosis plays out in the brain and body may provide insight into how brain inflammation occurs or is regulated and THAT could turn out to provide a new angle on understanding the role of brain inflammation an inflammation management which could be linked to understanding and developing new antipsychotic treatments. Definitely a line of work to keep an eye on.
Questions for Discussion:
- What is Toxoplasmosis and why is it something to be avoided (and how might that be accomplished)?
- Why is Toxoplasmosis of particular concern for pregnant women?
- How might a better understanding of Toxoplasmosis lead towards better antipsychotic treatments?
References (Read Further):
Laing, C., Blanchard, N., & McConkey, G. A. (2020). Noradrenergic Signaling and Neuroinflammation Crosstalk Regulate Toxoplasma gondii-Induced Behavioral Changes. Trends in Immunology.
Jones, J. L., & Dubey, J. P. (2012). Foodborne toxoplasmosis. Clinical infectious diseases, 55(6), 845-851. Link
Jones, J. L., Lopez, A., & Wilson, M. (2003). Congenital toxoplasmosis. American family physician, 67(10), 2131-2138. Link
El Saftawy, E. A., Amin, N. M., Sabry, R. M., El-Anwar, N., Shash, R. Y., Elsebaie, E. H., & Wassef, R. M. (2020). Can Toxoplasma gondii Pave the Road for Dementia?. Journal of Parasitology Research, 2020. Link
Mahami-Oskouei, M., Hamidi, F., Talebi, M., Farhoudi, M., Taheraghdam, A. A., Kazemi, T., … & Fallah, E. (2016). Toxoplasmosis and Alzheimer: can Toxoplasma gondii really be introduced as a risk factor in etiology of Alzheimer?. Parasitology research, 115(8), 3169-3174. Link
Elleboudy, N. A., Abdul-Rahman, S. A., Ismail, K. A., & Aal, W. M. A. (2015). Dementia and toxoplasmosis: Is there a link. Hell J Nucl Med, 18, 505-28. Link
Kirkpatrick, B., & Miller, B. J. (2013). Inflammation and schizophrenia. Schizophrenia bulletin, 39(6), 1174-1179. Link
Leza, J. C., García-Bueno, B., Bioque, M., Arango, C., Parellada, M., Do, K., … & Bernardo, M. (2015). Inflammation in schizophrenia: a question of balance. Neuroscience & Biobehavioral Reviews, 55, 612-626. Link
Müller, N. (2018). Inflammation in schizophrenia: pathogenetic aspects and therapeutic considerations. Schizophrenia bulletin, 44(5), 973-982. Link