Psychobiotic

Antibiotics and Your Brain

We like our stories neat, with good guys in white hats and bad guys in black, but nature scoffs at our binary plot lines. An important and timely example of our tendency to oversimplify is antibiotic use. Antibiotics are amazing life-savers, but they are not without side-effects. For one thing, they can have a surprising impact on our brain. Hal and Ava talk about this unexpected complexity with Antibiotics. References Butler, Mary I., Kiran Sandhu, John F. Cryan, and Timothy G. Dinan. “From Isoniazid to Psychobiotics: The Gut Microbiome as a New Antidepressant Target.” British Journal of Hospital Medicine (London, England: 2005) 80, no. 3 (March 2, 2019): 139–45. Gur, Tamar L., Brett L. Worly, and Michael T. Bailey. “Stress and the Commensal Microbiota: Importance in Parturition and Infant Neurodevelopment.” Frontiers in Psychiatry 6 (2015). Stilling, Roman M., Seth R. Bordenstein, Timothy G. Dinan, and John F. Cryan. “Friends with Social Benefits: Host-Microbe Interactions as a Driver of Brain Evolution and Development?” Frontiers in Cellular and Infection Microbiology 4 (2014): 147. Bhattacharyya, Shamik, Richard Darby, Pooja Raibagkar, Luis Gonzalez Castro, and Aaron Berkowitz. “Antibiotic-Associated Encephalopathy: A Comprehensive Review of 391 Reported Cases (P3.383).” Neurology 86, no. 16 Supplement (April 5, 2016): P3.383. Grill, Marie F, and Rama K Maganti. “Neurotoxic Effects Associated with Antibiotic Use: Management Considerations.” British Journal of Clinical Pharmacology 72, no. 3 (September 2011): 381–93. Get full access to Psychobiotic: The Gut-Brain Revolution at scottcanderson.substack.com/subscribe [https://scottcanderson.substack.com/subscribe?utm_medium=podcast&utm_campaign=CTA_4]

From Mom on Your Birthday: A Microbiota

Breast milk is an amazingly rich concoction of sugars, fats, and immune factors. It is a carrier for the main payload—a starter microbiota that includes bacteria and fungus from the mother and her mother before her. They are specially plucked from the mother's gut by dendritic cells and then ferried to the milk ducts via the lymphatic system. These microbes are accompanied by a rich broth of prebiotics to feed them. Most of the sugars in milk are for those microbes, not the baby. That seems sadistic, but it's not: The microbes convert those indigestible sugars into energy-packed fatty acids that feed the baby and nourish the gut lining. Hal and Ava offer an overview of this amazing maternal inheritance. References Neu, Josef, and Jona Rushing. “Cesarean versus Vaginal Delivery: Long Term Infant Outcomes and the Hygiene Hypothesis.” Clinics in Perinatology 38, no. 2 (June 2011): 321–31. doi:10.1016/j.clp.2011.03.008. Boix-Amorós, Alba, Fernando Puente-Sánchez, Elloise du Toit, Kaisa M. Linderborg, Yumei Zhang, Baoru Yang, Seppo Salminen, et al. “Mycobiome Profiles in Breast Milk from Healthy Women Depend on Mode of Delivery, Geographic Location and Interaction with Bacteria.” Appl. Environ. Microbiol., March 1, 2019, AEM.02994-18. https://doi.org/10.1128/AEM.02994-18. Funkhouser, Lisa J., and Seth R. Bordenstein. “Mom Knows Best: The Universality of Maternal Microbial Transmission.” PLOS Biol 11, no. 8 (August 20, 2013): e1001631. doi:10.1371/journal.pbio.1001631. Dinan, Timothy G., and John F. Cryan. “Gut Instincts: Microbiota as a Key Regulator of Brain Development, Ageing and Neurodegeneration.” The Journal of Physiology 595, no. 2 (2017): 489–503. https://doi.org/10.1113/JP273106. Sudo, Nobuyuki, Yoichi Chida, Yuji Aiba, Junko Sonoda, Naomi Oyama, Xiao-Nian Yu, Chiharu Kubo, and Yasuhiro Koga. “Postnatal Microbial Colonization Programs the Hypothalamic-Pituitary-Adrenal System for Stress Response in Mice.” The Journal of Physiology 558, no. Pt 1 (July 1, 2004): 263–75. Stilling, Roman M., Feargal J. Ryan, Alan E. Hoban, Fergus Shanahan, Gerard Clarke, Marcus J. Claesson, Timothy G. Dinan, and John F. Cryan. “Microbes & Neurodevelopment--Absence of Microbiota during Early Life Increases Activity-Related Transcriptional Pathways in the Amygdala.” Brain, Behavior, and Immunity 50 (November 2015): 209–20. doi:10.1016/j.bbi.2015.07.009. Get full access to Psychobiotic: The Gut-Brain Revolution at scottcanderson.substack.com/subscribe [https://scottcanderson.substack.com/subscribe?utm_medium=podcast&utm_campaign=CTA_4]

Sniffing out Schizophrenia and Depression

Two chemicals from breath samples, butyrate and trimethylamine, are sufficient to distinguish depression and schizophrenia with 80% accuracy. These chemicals are both produced by gut microbes. This implies that the correlation between gut microbes and these two mental conditions is surprisingly high. If, in a room full of people with a multiple mental issues, you can distinguish them by mere microbes, then perhaps we should be paying more attention to mere microbes. Hal and Ava discuss the implications of this amazing diagnostic. Henning, Daniush, Marian Lüno, Carina Jiang, Gabriela Meyer-Lotz, Christoph Hoeschen, and Thomas Frodl. “Gut–Brain Axis Volatile Organic Compounds Derived from Breath Distinguish between Schizophrenia and Major Depressive Disorder.” Journal of Psychiatry & Neuroscience : JPN 48, no. 2 (April 12, 2023): E117–25. Jia, Huang, Cai Yiwen, Su Yousong, Zhang Ming, Shi Yifang, Zhu Na, Jin Feng, Peng Daihui, and Fang Yiru. “Gastrointestinal Symptoms During Depressive Episodes in 3256 Patients with Major Depressive Disorders: Findings from the NSSD.” Journal of Affective Disorders, February 17, 2021. Get full access to Psychobiotic: The Gut-Brain Revolution at scottcanderson.substack.com/subscribe [https://scottcanderson.substack.com/subscribe?utm_medium=podcast&utm_campaign=CTA_4]

A Surprising Way That Exercise Improves Your Mind

Is it time to get off the sofa? Exercise is one of the best things you can do for your health, but it also has a surprising impact on your mood. Hal and Ava talk about the intriguing connection between exercise, your gut microbes and your mood. This is the gut-brain axis and it is involved with your microbiota: the bacteria, fungi, and viruses that live in your gut. Learn how exercise can boost your good microbes. Sanborn, Victoria, and John Gunstad. “The Potential Mediation of the Effects of Physical Activity on Cognitive Function by the Gut Microbiome.” Geriatrics 5, no. 4 (September 25, 2020): 63. Bressa, Carlo, María Bailén-Andrino, Jennifer Pérez-Santiago, Rocío González-Soltero, Margarita Pérez, Maria Gregoria Montalvo-Lominchar, Jose Luis Maté-Muñoz, Raúl Domínguez, Diego Moreno, and Mar Larrosa. “Differences in Gut Microbiota Profile between Women with Active Lifestyle and Sedentary Women.” PLOS ONE 12, no. 2 (February 10, 2017): e0171352. Get full access to Psychobiotic: The Gut-Brain Revolution at scottcanderson.substack.com/subscribe [https://scottcanderson.substack.com/subscribe?utm_medium=podcast&utm_campaign=CTA_4]

A Microbial Signature of Cognitive Impairment.

Ava and Hal talk about how people with fewer and less-diverse gut microbes are more likely to have cognitive impairment, including dementia and Alzheimer’s. That’s according to a new study from Monash University of Australia and Jinan University of China.Reference Wang, Jing, Gong Zhang, Hao Lai, Zengbin Li, Mingwang Shen, Chao Li, Patrick Kwan, et al. “Characterizing Gut Microbiota in Older Chinese Adults with Cognitive Impairment: A Cross-Sectional Study.” Journal of Alzheimer’s Disease. 2024 Aug 30.  Subscribe to Psychobiotic [https://scottcanderson.substack.com/]Substack. It's free! Get full access to Psychobiotic: The Gut-Brain Revolution at scottcanderson.substack.com/subscribe [https://scottcanderson.substack.com/subscribe?utm_medium=podcast&utm_campaign=CTA_4]