One study I found particularly interesting investigated whether or not anxiety could be linked to gut flora. Researchers took 'fearless' mice and 'anxious' mice and swapped their gut bacteria; so the fearless mouse now had the anxious mouse's microbiota (and vice versa). By altering the microbes of the gut, the anxious mice became bold while the fearless mice became timid. Additionally, the researches investigated the effects of diet, probiotics, and antibiotics on a group of aggressive mice. Due to various alterations of microbes, the aggressive mice appeared to become more docile (Collins, et al., 2013).
You might be asking yourself, 'how could this be possible?!' Well, by measuring the brain chemistry of mice with altered gut microbiota, researchers discovered chemical changes in areas of the brain dealing with emotion/mood as well as an increase in a chemical known as brain-derived neurtrophic factor. Moreover, brain-derived neurtrophic was found to be increased in the hippocampus region of the brain, and is believed to influence both learning and memory (Bercik, et al., 2011).
You might be asking yourself, 'how could this be possible?!' Well, by measuring the brain chemistry of mice with altered gut microbiota, researchers discovered chemical changes in areas of the brain dealing with emotion/mood as well as an increase in a chemical known as brain-derived neurtrophic factor. Moreover, brain-derived neurtrophic was found to be increased in the hippocampus region of the brain, and is believed to influence both learning and memory (Bercik, et al., 2011).
Because this is a relatively new area of study, there are still many unknowns. However, researchers are hopeful that eventually alteration of gut flora could become an effective treatment for various disorders of the central nervous system, including psychiatric disorders (Collins, et al., 2013).
I found this short video really informative (and fun). It explains gut flora across the human body and discusses why gut microbiota are so important. Although it does not discuss the effects of microbiota on the brain, I still thought it might help some of you grasp the idea of the human microbiome. Enjoy!
I found this short video really informative (and fun). It explains gut flora across the human body and discusses why gut microbiota are so important. Although it does not discuss the effects of microbiota on the brain, I still thought it might help some of you grasp the idea of the human microbiome. Enjoy!
(Gudenkauf, 2013).
References:
Bercik, P., Verdu, E. F., Denou, E., Collins, S. M., Mccoy, K. D., Macri, J., et al. (2011). The Intestinal Microbiota Affect Central Levels of Brain-Derived Neurotropic Factor and Behavior in Mice.Gastroenterology, 141(2), 599-609.e3.
Collins, S. M., Kassam, Z., & Bercik, P. (2013). The adoptive transfer of behavioral phenotype via the intestinal microbiota: experimental evidence and clinical implications. Current Opinion in Microbiology, 16(3), 240-245.
Gudenkauf, A. (Producer). (2013). The Invisible Universe of the Human Microbiome. United States: NPR.
I loved that video! I love the idea that we have tiny 3-eyed mini-dinosaur-looking creatures living in our bodies! The influence of the microbiome on the brain is also absolutely astounding. Would you be able to explain a little more about how brain-derived neurotrophic factor works? I’m really looking forward to finding out what else our microbiome is capable of doing!
ReplyDeleteBrain-derived neurotrophic factor plays an important role in brain plasticity. Brain plasticity is the ability of the brain to alter its structure and functions due to environmental or bodily changes. More specifically, synaptic plasticity (the ability of a chemical syapses to change strength) is related to encoding and believed to be essential in the development of memories and learning. In fact, brain-derived neurotrophic factor has even been linked to the process of long-term potentiation. Long-term potentiation refers to enhanced communication between two neurons for a long period of time. This enhancement is believed to improve encoding, thus having significant effects on learning and memory. However, this is a new area of study so how exactly brain-derived neurotrophic factor facilitates these processes in the brain is still being investigated. Nonetheless, studies suggest there is a link between encoding and brain-derived neurotrophic factor. For example, researchers who removed the coding sequence for the brain-derived neurotrophic factor gene in mice, found that the mice displayed significantly less long-term potentiation (Korte et al., 1995).
ReplyDeleteReference:
Korte, M., Carroll, P., Wolf, E., Brem, G., Theonen, H., & Bonhoeffer, T. (1995). Hippocampal Long-Term Potentiation Is Impaired In Mice Lacking Brain- Derived Neurotrophic Factor. Proceedings of the National Academy of Sciences, 92(19), 8856-8860.
This is awesome! Have they been able to show how the microbes interact with the genetics of the mice? Neuroticism has been shown to be a heritable personality trait so I'm wondering how the microbes mess with this - perhaps they 'trigger' the switching on or switching off of behavioural traits at the molecular level?
ReplyDeleteGreat video and great blog post. It was easy to follow and understand. Did the article say anything about the diet people/mice should consume to encourage the growth of good gut microbiota?
ReplyDeleteThat video was so great! I loved that it was a pretty cartoon! it actually made me laugh :) thanks for that - I actually learned a lot and gained such an appreciation for these lil microbe characters... I might even start saying goodnight to them! ... (not really! just jokes! ;P )
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