About the only independent variable appearing to cause permanent change in the gut is dietary change, but did you know that your microbiome and microflora are drug manufacturers?
It’s a little known fact that one of our body’s innate pharmacies resides in our gut.
Where, exactly, in our gut, you ask?
Well, in neurochemicals isolated in various microbial species whose diversity depends on our microbiome’s health. This speaks to another emerging area of interest: probiotics as pharmacy.
This article will briefly discuss five neurochemical isolated from various genera of normal gut bacteria:
1. GABA: Lactobacillus and Bifidobacterium. GABA is the main inhibitory neurotransmitter in the central nervous system, helping to induce a parasympathetic response, and significantly impacting and regulating various processes both physiologically and psychologically. Several animal studies indicate that various species of Lactobacillus and Bifidobacterium are capable of producing GABA in the gut. (1, 2, 3, 4)
2. Norepinephrine: Escherichia, Bacillus, and Saccharomyces. Norepinephrine is a naturally occurring neurotransmitter active during a sympathetic response which is upregulated during fight or flight and acts as a stress hormone. Several animal studies have shown that various species of Escherichia, Bacillus, and Saccharomyces play a role in upregulatting and producing norepinephrine. (5, 6, 7, 8)
3. Serotonin: Candida, Streptococcus, Escherichia, and Enterococcus. Serotonin is a key hormone, an estimated 90% of which is thought to be produced in the gut, that is key in mood stabilization and happiness, as well as impacting learning, attention, and memory processes. Several animal studies have indicate that various species of Candida, Streptococcus, Escherichia and Enterococcus play a role in serotonin production. (9, 10, 11, 12)
4. Dopamine: Bacillus and Serratia. Dopamine is a key neurotransmitter in our ability to experience pleasure, as well as cognitive control in our prefrontal cortext. Several animal studies have shown that certain species of Bacillus and Serratia play a key role in the production of dopamine. (13, 14)
5. Acetylcholine: Lactobacillus. Acetylcholine is the main neurotransmitter of the parasympathetic nervous system and its receptors are present all throughout our smooth muscle, blood vessels, and even heart muscle, as it helps to downregulate the function of certain organs during rest and digest. Several animal studies show that various species of Bacillus and Serratia are capable of producing acetylecholine in the gut. (15, 16)
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