bacterial names come from the Linnaean binomial system. Italicized, latinized names such as
Escherichia coli are
abbreviated to E. coli
Their names are derived from descriptions, places, or people. They now can reflect evolutionary relationships via genomic data.
evidence shows that our microbiome produces
neurotransmitters and their precursors, stimulates the
enteric and vagus nerves, and affects brain function and cognition. correlations between the gut microbiome and the central nervous system have sparked a new research field called Neuromicrobiology.
Microbiome-targeted interventions are being tested but
specifics re the host-microbiome relationship is still not clearly understood.
our microbiome is a community of all microbes that live in our body.
Our microbiota is acquired starting at birth from mom's birth canal and breast milk. then dad's kisses. Sister's hand holding. The dog licking fingers. We then encounter microbes in/on the soil and water and plants. We eat microbes with our food.
1. bacteria synthesize neurotransmitters and their precursors
Gut bacteria produce hundreds of neurochemicals used by our brains to regulate many physiological and mental processes such as cognition, sleep and mood.
“microbe” is used to describe organisms that are too small to be seen with the naked eye and include bacteria, archaea, fungi, protists, and viruses.
application of broad-spectrum antibiotics that target bacteria indiscriminately, eliminating harmful pathogens but also wiping out beneficial gut microbes. diverse beneficial populations, especially small, sensitive ones like Bifidobacterium, are killed off leading to less stable ecosystems. with competition gone, pro-inflammatory bacteria (like Proteobacteria) and antibiotic-resistant genes can bloom.
where does this microbiome come from?
Most microbes do not have the tools to join our microbiome. Others that do must compete with the microbes already established. The process of selection occurs.
Bacteria and archaea are single-celled organisms that do not enclose their genetic material in a nucleus.
eukaryote
which bacteria are we talking about??
trains immune cells to not react to harmless substances and promotes anti-inflammatory assets like Treg cells
Soooooo...
37 trillion
Viruses are also considered microbes although since they can only reproduce by using another cell’s machinery to make new viruses,
they are not usually considered alive.
100 trillion
mostly GI tract but also skin surface,
mouth, respiratory tract, reproductive tract, nasal passages, urinary tract, and blood
our microbiome aids digestion, produces vitamins, and supports our immune function.
what's the take-away?
competes with pro-inflammatory microbes.
good news..
breast milk provides probiotic bacteria to populate the baby’s gut.
it also contains prebiotic complex carbs/proteins babies can't digest but that serve as food for Bifidobacteria, microbes which line the baby's intestines and prevent infection by pathogens.
that help us promote
good gut health
3. bacteria produce
Short-Chain Fatty Acids (SCFAs)
such as butyrate from fiber which influence the brain and maintain the blood brain barrier (BBB).
the future...
1. Personalized Microbiome Therapies:
analyze individual microbiomes to create tailored probiotics, prebiotics, or dietary plans for specific
conditions.
2. Neurodegenerative Diseases:
understanding relationship between gut microbes
and Alzheimer's (AD) & Parkinson's (PD) to create
prevention or treatment strategies
3. Mental Health Disorders:
how do specific microbial strains and their metabolites influence depression, anxiety, and
autism spectrum disorder (ASD) symptoms.
4. Early Life & Development:
Understanding the gut-brain axis during
neurodevelopment. how does the maternal microbiome influence offspring health?
5. And other microbes?
which other microbes (like fungi) and their
metabolites influence our gut biome?
what is dysbiosis?
where...
although 1/2 million microbe species populate our planet, just a few hundred have evolved to symbiotically live with humans!
your vagus nerve, cranial nerve X (10), is the primary nerve of your parasympathetic (rest & digest) nervous system
which controls functions such as digestion, heart rate, blood pressure, respiration, mood, immune system responses,
skin and muscle sensations, speech and taste.
the left and right vagal nerves contain 75% of your parasympathetic nervous system’s nerve fibers, communicating via a two way system between
your brain, heart and digestive system.
Neurotransmitters
produced by your microbiota:
1. Serotonin:
neurotransmitter affects mood, sleep, appetite
90%+ produced in your gut
2. GABA (Gamma-aminobutyric acid) inhibitory neurotransmitter controls fear and anxiety
3. Dopamine & Norepinephrine:
impact reward, focus, and mood
4. Glutamate:
key excitatory neurotransmitter necessary for learning and memory
4. Immune System: Gut microbes modulate inflammation, which sends signals to the brain
4. bacteria reduce inflammation by strengthening the gut barrier to prevent 'leaky gut' and endotoxins from entering the blood supply.
SCFAs are also anti-inflammatory.
symbiosis: mutualism, commensalism, parasitism
SCFAs like butyrate are produced when anaerobic gut microbes ferment indigestible dietary fibers (prebiotics) in the large intestine. SCFAs support brain function by:
a. strengthening the BBB by helping to form form tight junctions between brain endothelial cells, reducing permeability.
b. influencing the production of neurotransmitters like serotonin, dopamine, and GABA.
c. calming overactive microglia (your brain's immune cells) and reducing neuroinflammation.
d. altering gene expression by inhibiting histone deacetylases.
how do bacteria differ from virus?
3 pints worth!
good gut health = a balanced gut microbiome.
help maintain it by a diet rich in diverse fibers, probiotics (fermented foods like yogurt, kimchi), and prebiotics (garlic, onions, oats), with stress management, sufficient sleep, staying hydrated, exercising, avoiding a lot of processed foods and
avoiding unnecessary antibiotics
bacteria
our microbiome
healthy gut flora must be nurtured
are microbes found in/on our bodies?
why??
antibiotics and dysbiosis
Microbes identify our cell's surface proteins to help them find their niche in/on our bodies...chemical communication and physical cues. temperature etc.
Our microbiome is not randomly assembled. Rather, it is a complex dance of mutual selection.
Long-term consequences
Inflammation: Dysbiosis can impair the microbiota's ability to control gut inflammation, potentially leading to inflammatory bowel diseases (IBD).
Immune System Weakening: Prolonged imbalance can weaken the immune system.
Gut-Brain Axis Issues: Impacts the gut-brain connection, linked to anxiety, depression, and cognitive issues.
Chronic Diseases: Early-life antibiotic exposure is linked to later development of asthma and autoimmune conditions.
what are bacteria?
let's take a quick look at prokaryotes
btw...Escherichia coli (E. coli) is named after its discoverer, German pediatrician Theodor Escherich, and its location, the colon. "Escherichia" honors Escherich (who found the bacteria in infant feces), and "coli" comes from the word colon.
so many microbes...
Eukarya include all the plants and animals you can see and many
microbes including some fungi some algae, and protists like amoebas.
serotonin is a crucial neurotransmitter and hormone. it regulates mood, sleep, appetite, digestion, memory, and behavior, and also significantly impacts gut health, and bowel function.
what do we call these bacteria?
2. bacteria activate our
Vagus Nerve
which acts as a direct line of communication between our gut and our brain
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