Mind Altering Microbes: How your gut microbiome may influence your mood

"I've got a gut feeling about this"

While we have certainly heard that appetite and digestion are controlled by the enteric nervous system  (also known as "the master control panel in your gut"), who would've thought that the gut might also control your emotions and mood?  It's no wonder the old sayings, like "I've got a gut feeling about this", "That movie was gut-wrenching", or  "Come on, gut it out!" ring so true.  In fact I'd venture to say when we are trusting our intuition we associate it with having a "gut feeling" about something.

From the research it is now clear that gut microbes have an affect on inflammation, pain, eating behaviors, food cravings, mood and other seemingly unrelated symptoms, such as depression or uncontrolled anxiety.  In addition, it is common for depression and anxiety to co-exsist with disorders such as IBS (irritable bowel disorder).

It goes both ways...

Yes, it's true!  Did you know the gut-brain axis provides a way of communicating both directions using signals, such as neurotransmitters, hormones and cytokines?  This means that your gut bugs actually talk to your brain to influence emotions.  Equally important the emotions you feel and neurotransmitters produced by the brain have a profound effect on the gut as well.  We know that dysfunction in this communication between gut and brain can lead to various diseases, including depression and anxiety.  Who knew that the composition of your gut microbes could play such a great role in your mood?  The next time you get angry at your spouse or are overcome with sadness making you want to curl up in bed you can simply say, "Don't blame me...It's my gut microbes's fault!"  and you may be right on target!

The human gut is populated by more than 100 trillion microbes, which means there is more bugs in your gut than cells in your body.   And the genetic material contained by microbes in your gut is 150X that of the genetic material from human origin.  Most experts agree we have more than 1000 different species in our gut and over 7000 different strains.  We know that as we are exposed to stress, chemicals, antibiotics, and toxins, the diversity of the microbiome decreases and we know that the less diverse or microbiome, the more susceptible we are to illness and disease.

A baby's colonization of the gut first occurs at birth with vaginal exposure to the mother's microflora.  Did you know that c-section baby's have gut microbes more akin to skin flora than gut flora after birth?  And some studies show that throughout the entirety of life, they may never regain the normal diversity of vaginally delivered infants.

These are just a few of the functions of these bugs residing in your gut:

• Development of your immune system function
• Assisting with bowel movements and gut motility
• Maintaining intestinal cell barrier integrity (keeping the the good stuff in and the bad stuff out)
• Aiding in digestion and absorption of specific vitamins and minerals
• Controlling fat absorption and distribution

Pathways involved in communication between the gut microbes and brain.

Microbes and Stress

What is increasingly clear is that there is bi-directional communication between our gut microbes influencing the central nervous system and brain... and the reverse; communication between our brain influencing microbial composition.   Did you know that stress affects the gut microbes, too?

These are the top 3 ways that chronic stress affects the gut:

1. Increases the levels of inflammatory cytokines (IL-6, TNF-alpha) which can changes gut microbe populations.
2. Increases permeability of the gut lining, which is linked to many autoimmune diseases  (Hashimoto's thyroiditis, lupus, rheumatoid arthritis, multiple sclerosis and many others).
3. Allows bacteria to cross over into the bloodstream where the bacterial coating (LPS) can trigger an intense inflammatory response in the body.

So how do the gut microbes contribute to anxiety and depression?

Here are some of the mechanisms by which the gut microbes influence the brain and emotions:

• Altered microbial composition: Both probiotic ("good guys") administration and harmful infectious bacteria ("bad guys") have both shown to have an effect on the brain and emotions.  One study showed supplementation with probiotics decreased anxiety.
• Immune Activation:  Bacteria in the gut have been shown to activate the immune system and increase production of harmful pro-inflammatory cytokines.   There are many studies showing a link between increase in certain cytokines and depression (see below if you want to read more)
• Vagus nerve:  This is one of the main controls of the parasympathetic system that calms our fight or flight response and allows our body to relax and feel calm.  Activation of the vagus nerve and release of acetyl-choline has been shown to have a profoundly calming and anti-inflammatory effect on the body.  Most of the effects of gut microbes on the brain and body have been shown to be dependent on vagal nerve activation.
• Tryptophan metabolism:  Tryptophan is an extremely important amino acid and the raw material needed to make serotonin (think "the happy neurotransmitter") by the body.  There is a pathway, called the kynurinine pathway that involves metabolism of tryptophan and accounts for nearly 95% of the stores of tryptophan in the body.  In the case of pathogenic microbial infections in the gut (bacteria, yeast, or parasites) this pathway may be activated and "steal" from your body's tryptophan stores.  This leads to depletion of serotonin stores and may result in insomnia and depression.
• Microbial metabolites:  Bacteria in the gut help produce bile acids and short chain fatty acids (SCFAs) which are essential for human physical and mental health.
• Neurometabolites: Crazy but true... bacteria have the ability to produce many neurotransmitters and metabolites that have direct action on brain and thought.   Did you know studies show microbes can even influence your food cravings?!
• Bacterial cell wall sugars:  Perhaps most fascinating of all, the outer coatings of bacteria contain sugar molecules that can directly signal immune and hormonal systems into action.  This is the mechanism thought to be responsible for the healthy effects of probiotics on the gut and brain.

The bottom line is there is a growing body of evidence that suggests gut microbes play a large role in regulation in behavior and brain chemistry and are relevant to development of depression and anxiety.

So perhaps the best antidepressant is a healthy whole food diet and a high potency probiotic to fuel a healthy gut microbiome!

Check out Part II - Six Simple Steps to Treat Depression

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Further Reading:

• Psychoneuroimmunology Meets Neuropsychopharmacology: Translational Implications of the Impact of Inflammation on Behavior
• Inflammatory Cytokines in Depression: Neurobiological Mechanisms and Therapeutic Implications
• Cytokine variations and mood disorders: influence of social stressors and social support
• Increased IgA and IgM responses against gut commensals in chronic depression: Further evidence for increased bacterial translocation or leaky gut
• Mind-altering microorganisms: The impact of the gut microbiota on brain and behaviour
• Stress and the Gut

Balancing Your Brain Chemistry: Testing and Treating Neurotransmitter Imbalances

Neurotransmitters are molecules that regulate brain function. They are chemicals which relay messages from nerve to nerve both within the brain and outside the brain. They also relay messages from nerve to muscle, lungs, and intestinal tracts.

They can accentuate emotion, thought processes, joy, elation and also fear, anxiety, insomnia and that terrible urge to over indulge in food, alcohol, drugs, etc.

In short, neurotransmitters are used all over the body to transmit information and signals. They are manufactured and used by neurons (nerve cells) and are release into the synaptic clefts between the neurons.  

These brain chemicals communicate information throughout our brain and body.  They relay signals between nerve cells, called “neurons.”  The brain uses neurotransmitters to tell your heart to beat, your lungs to breathe, and your stomach to digest.  They can also affect mood, sleep, concentration, weight, and can cause adverse symptoms when they are out of balance. Neurotransmitter levels can be depleted many ways.  As a matter of fact, it is estimated that 86% of Americans have suboptimal neurotransmitter levels.  Stress, poor diet, neurotoxins, genetic predisposition, drug (prescription and recreational), alcohol and caffeine usage can cause these levels to be out of optimal range.

There are two kinds of neurotransmitters – INHIBITORY and EXCITATORY.  Excitatory neurotransmitters are not necessarily exciting – they are what stimulate the brain.  Those that calm the brain and help create balance are called inhibitory.  Inhibitory neurotransmitters balance mood and are easily depleted when the excitatory neurotransmitters are overactive.  

Inhibitory Neurotransmitters

• SEROTONIN is an inhibitory neurotransmitter – which means that it does not stimulate the brain.  Adequate amounts of serotonin are necessary for a stable mood and to balance any excessive excitatory (stimulating) neurotransmitter firing in the brain.  If you use stimulant medications or caffeine in your daily regimen – it can cause a depletion of serotonin over time.  Serotonin also regulates many other processes such as carbohydrate cravings, sleep cycle, pain control and appropriate digestion.  Low serotonin levels are also associated with decreased immune system function.
• GABA is an inhibitory neurotransmitter that is often referred to as “nature’s VALIUM-like substance”.  When GABA is out of range (high or low excretion values), it is likely that an excitatory neurotransmitter is firing too often in the brain.  GABA will be sent out to attempt to balance this stimulating over-firing.
• DOPAMINE is a special neurotransmitter because it is considered to be both excitatory and inhibitory.  Dopamine helps with depression as well as focus, which you will read about in the excitatory section.

Excitatory Neurotransmitters

• DOPAMINE is our main focus neurotransmitter.  When dopamine is either elevated or low – we can have focus issues such as not remembering where we put our keys, forgetting what a paragraph said when we just finished reading it or simply daydreaming and not being able to stay on task.  Dopamine is also responsible for our drive or desire to get things done – or motivation.  Stimulants such as medications for ADD/ADHD and caffeine cause dopamine to be pushed into the synapse so that focus is improved.  Unfortunately, stimulating dopamine consistently can cause a depletion of dopamine over time.
• NOREPINEPHRINE is an excitatory neurotransmitter that is responsible for stimulatory processes in the body.  Norepinephrine helps to make epinephrine as well.  This neurotransmitter can cause ANXIETY at elevated excretion levels as well as some “MOOD DAMPENING” effects.  Low levels of norepinephrine are associated with LOW ENERGY, DECREASED FOCUS ability and sleep cycle problems.
• EPINEPHRINE is an excitatory neurotransmitter that is reflective of stress.  This neurotransmitter will often be elevated when ADHD like symptoms are present.  Long term STRESS or INSOMNIA can cause epinephrine levels to be depleted (low).  Epinephrine also regulates HEART RATE and BLOOD PRESSURE.

How do we measure neurotransmitters?
Normally the neurotransmitter is released in response to an electric signal. After binding to the receptor site on the second neuron, the chemical is then recycled. However, only about 60% of the neurotransmitter is recycled. The rest is carried away in the blood stream and excreted in the urine. We can measure urinary levels of neurotransmitters, and get a good idea of their levels within the body.

We measure neurotransmitters directly. It has been found that blood and saliva levels are not particularly useful. Some of the neurotransmitters, epinephrine in particular, have wildly fluctuating levels depending on the person’s sate of mind. (If we are approaching them with a needle to draw blood, the levels will be very high within a few seconds, so blood levels do not give us a picture of the person’s rising neurotransmitter levels. )

Urine levels seem to be representative of what is actually going on in the system.

When we see low urinary levels we can be sure that the body’s stores are low. When we see high urinary levels, the issue is more confusing. In over 90% of cases we can be sure that although levels are apparently high, this only relates to biological activity of the hormone. In actual fact, the total body stores are almost certainly low.

We see this particularly in people who are taking antidepressant medication, especially serotonin reuptake inhibitors like Prozac, Paxil, Wellbutrin. These medications prevent the nerve cells from taking Serotonin back out of the system (hence the name, re-uptake inhibitors).

However, since the levels are high at the synaptic junction, the body thinks that the levels are high overall, and makes every effort to get rid of as much serotonin as possible. Since the neurotransmitters are excreted in the urine, we therefore see high urinary levels. Not only does the body try to get rid of the neurotransmitters, it also stops making them, in an effort to reduce the levels at the synaptic junction. In the long run, total body stores are depleted, and eventually the urine levels will fall.

Highly depressed moody people are extremely low in serotonin and norepinephrine, but will probably have high urinary levels because they are losing so much at any given point in time.

If they have insomnia, it is likely that their dopamine and/or PEA levels is high.

Highly agitated anxious irritated people will probably have high epinephrine, norepinephrine and dopamine, and relatively low serotonin levels. They may also have markedly elevated PEA levels.

In addition, the sex hormones influence multiple neurotransmitters. Estrogen has an anti-dopamine effect, in addition to inducing the formation of new synapses.

Progesterone increases the effect of GABA and reduces neurotransmitter activity. Estradiol decreases the level of the enzyme which inactivates the serotonin and dopamine (monoamine oxidase, MAO), thus effectively increases the effects of serotonin and dopamine, where progesterone decreases their effects.

DHEA enhances the effect of serotonin and norepinephrine, thus it enhances cognitive function and reduces depression. Cortisol inhibits the release of catecholamines, and increases the effect of GABA, thus reducing anxiety.  

TREATING NEUROTRANSMITTER IMBALANCES:

1 - We can increase our dietary intake of tryptophan. American diets tend to be high in carbohydrate and low in protein. Foods high in tryptophan are mostly high protein foods:

• Cottage cheese (dry) 450 mg per cup
• Cottage cheese (creamed) 336 mg per cup
• Fish and other seafoods 800-1300 mg per pound
• Meats 1000-1300 mg per pound
• Poultry 600-1200 mg per pound
• Peanuts, roasted with skin 800 mg per cup
• Sesame seeds 700 mg per cup
• Dry, whole lentils 450 mg/cup
  

2 - We can increase our amount of exercise. Exercise leads to more efficient use of insulin, thus reducing insulin resistance and decreasing the amount of food which is stored as fat. When the cells process nutrients better, they make neurotransmitters better.
3  Reduce our intake of caffeine and alcohol. Caffeine makes the body think is it under stress, which raises the cortisol level, raises the insulin level, and causes carbohydrates to be deposited as fat.  Alcohol will deplete seretonin levels over time
4 - Make sure that blood chemistry is in balance.

MIMICS OF DEPRESSION:

• Hypothyroidism can cause a picture similar to depression, and is easily correctable.
• Vitamin B12 and folate deficiencies can also cause a depression like mimic.
  

5 -  We can supplement the needed amino acids and cofactors,so that the body can make the required neurotransmitters.

Remember that neurotransmitters are all over the body and that they are interdependent. We cannot change one level without causing a ripple effect in all the other neurotransmitters. We can start with serotonin, but we need to add support for all the other neurotransmitters whose levels are not optimal.


6 - Dr Carnahan will retest the urine levels every 6-8 weeks, until they are optimal.

Call today for more information on how Dr Carnahan can help you balance your neurotransmitters #303-443-9590