Using Bacteria To Program Your Brain

Researchers have found that the bugs in your gut can influence your brain’s responses. Working with germ-free rodents, they discovered the animals’ behavior changed when certain germs were introduced into their gut through their diet. Intrigued, other universities tested the effect of beneficial bacteria (probiotics) on people’s mood and found that the gut bacteria consumed by participants actually changed their mood. This was verified by brain scans, blood and urine tests for chemicals produced by the body that influenced mood and physiological responses.

Considering that microorganisms in our gut outnumber cells in our body ten to one, it is not surprising that the chemicals that they produced could travel to our brain and alter our brain function. In fact, our Central Nervous System (CNS) only produces five percent of serotonin, a neurotransmitter that influences mood, memory, learning, digestion, sleep and sexual desire activities. The remainder 95 percent is manufactured by gut bacteria. Communication and sharing of chemicals go both ways between our brain and microbes. The result is reflected through mood and behavior.

Besides brain chemistry, this invisible army of workers in our gut also influences inflammation and pain perception, the body responds to stress, modulates our immune system and even help ‘program’ some aspects of brain development through influencing neural development.

Bacteria-Brain Communication

While harmful bacteria (pathogens) can jack up anxiety and depression, the good bacteria (probiotics) calms you down and lift your mood. This is because bacteria in our gut and our brain are constantly sending messages to each other through a number of channels.

1. Our IMMUNE CELLS are like the police force, constantly patrolling our body for break-ins, invasion and attack by pathogens and foreign substances. This police force and the chemicals they synthesize are used as messengers.

2. Sometimes gut bacteria use the vagus nerve to communicate with the brain. Researchers in Ireland fed Lactobacillus to mice that resulted in behavior change. When they cut the vagus nerve (the neural conduit between gut and brain) in mice, the effect that Lactobacillus exerted earlier on brain biochemistry, stress response and behavior evaporated.

3. The third method of communication is through neurochemical. Gut bacteria and brain produce and respond to the same neurochemicals (neurotransmitters).

A joint Duh-British Pediatric Research published in Nature pointed out, “Accumulating evidence has suggested the importance of the gut microbiome in this bidirectional communication system and as a result, the concept of the microbiome-gut-brain axis has emerged.” [Manon J. N. L. Benders]

Research into this exciting new field is still preliminary. Scientists still have to ascertain which bacterial strains are absolutely vital to mental functioning, or whether a combination of bacteria in the right balance is needed to influence mental functioning.

Bacteria-Brain Communication

FUNCTION OF NEUROTRANSMITTERS

GABA

Our brain, certain bacteria and fungi produce GABA.

It is a neurotransmitter that mutes neuronal activity, keeping stress, anxiety and depression in check. GABA also regulates the growth of embryonic and neural stem cells as well as influences the development of neural progenitor cells.

Scientists found that GABA deficiency in certain parts of the brain can trigger epilepsy.

This neurotransmitter plays a role in regulating pain and inhibits inflammation. Recent studies revealed that immune cells called macrophages also possess GABA receptors enabling microbes to ‘talk’ to them. Preliminary studies using Bifidobacterium dentium suggested bacteria may be able to reduce inflammation associated with inflammatory bowel disease, which is an immune response from our body’s police force.

The bacteria, Lactobacillus, has been shown to increase GABA Receptors and change emotional behavior. Prof John F Cryan pointed out, “bacteria play around with the same brain chemicals in the brain that antidepressants and anti-anxiety drugs do.” next time you feel depressed, eat a cup of yogurt – it is full of Lactobacillus.

Acetylcholine

Egg yolk is a very good source of choline, a nutrient needed to synthesize acetylcholine. It is also rich in an essential amino acid called ‘tryptophan’, which is metabolized into the neurotransmitter, serotonin.

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This ancient essential molecule is found in most of the cells in our body. It was around when the first single celled living organism appeared on earth and is used for fundamental cellular development and function. It is involved in secretion, absorption of nutrients, metabolism, membrane development and regulation of immune response. Acetylcholine (ACh) is needed for many vital functions, both non-neuronal and neuronal. Your mind will slow down if you are low on ach. Your body cannot function without ach to enable proper functioning of your cells.

Acetylcholine (Ach) disruption is a primary cause of depression. Damage to the Ach system cause memory problems. Researchers found 90% loss of acetylcholine in the brains of people suffering from Alzheimer's, which is a major cause of senility.

Ach is involved in REM (dream) sleep, which is the restorative part of the sleep cycle when the brain is more active.

It is responsible for much of stimulation of muscle including muscles in the gut, heart and lungs. Without Ach, your heart will stop beating, you cannot breathe. Lethal poisons of cobra, bacterium Clostridium botulinum, and puffer fish kill by targeting Ach to prevent neurotransmission.

It is a neuromodulator in both peripheral nervous system (PNS) and in the central nervous system (CNS).

ACh is needed for sensory perception (seeing & hearing), sustaining attention (increased responsiveness to sensory stimuli) and learning as well as encoding of new memories.

Serotonin

Refer to 'HAPPY FOODS‘ for food sources.

This neurotransmitter calms your nerves and is intimately involved with emotion and mood. It alleviates mood, improve cognitive function, facilitate greater concentration and vitality.

Research indicates Mycobacterium trigger release of serotonin. Mice fed Mycobacterium were put through stressful tasks. When the bacterium was removed from their diet, they continued to perform better than the control group for about three weeks. As the bacterium left their system, they gradually reverted to their normal selves.

Too little serotonin has been shown to lead to depression, problems with anger control, obsessive-compulsive disorder, and suicide. Too little also leads to craving for carbohydrates (starchy foods) and insomnia.

Stress hormones

Did you notice that when you are stressed, you are more susceptible to infection and have more aches and pains? Blame the stress hormones. Researchers found stress hormones increase pathogenic bacteria growth and virulence. The nasty microbes have receptors on their surface that can home in on stress hormones released by our body during physical or mental stress. [BMC Microbiology, Volume 14]

Adrenaline and Norepinephrine are stress hormones that enhance growth of pathogenic bacteria and help them to attach more firmly to host cell. That is why when you are stressed, pathogenic bacteria growth explodes. Cortisols are stress hormones that lowers your immunity, decrease libido and increase blood pressure and sugar.

A 2008 study led by psychologist Simon Knowles found that stool samples taken from Australian University students during exam week contained fewer lactobacilli compared to the relatively untroubled first days of the semester.

Stress chemicals not only increase pathogenic microbes, they seem to reduce beneficial microbes as well. Studies using rodents and monkeys produce the same result.

More on chemicals produced by your body: JUMBLEBLOG: CHEMISTRY OF SLEEP

 

What is prebiotic?

Prebiotic is a carbohydrate in the form of soluble fiber that is non-digestible to humans, thus generally providing low calories to our diet. However, when the non-digestible fiber passes intact through the stomach and small intestines and reached the large intestines, selected indigenous good bacteria ferments and extracts the nutrients within in the form of vitamins, minerals, amino acids (protein) and other goodies.   The good bacteria multiply, crowding out the pathogens that could not digest the fiber. Any excess not taken up by probiotics is absorbed through the intestinal wall to benefit us.

Characteristics of Prebiotics

All the food we eat provides nutrients not only for us, but for all the microbes in our gut. However, food classified as ‘prebiotic’ has specific characteristics:

·         Human’s salivary and intestinal digestive enzymes cannot break down the fiber.

·         The fiber reaches the colon intact.

·         Can be fermented by specific anaerobic bacteria in the colon.

·         Prebiotics selectively stimulates the growth and/or activity of one or a limited number of beneficial anaerobic microbes in the colon.

·         It does not promote toxin-producing and/or disease causing microbes.

·         As a result, prebiotic influences the species composition and metabolic characteristics of intestinal microbes.

·         Prebiotics elicit systemic physiological functions.

·         Confer important health benefits.

As you can see, it is possible to modulate the composition of the colonic micro flora    through foods for better gastrointestinal health.

Benefits of Prebiotics

·         Increase good bacteria & reduce harmful bacteria in the gut.
Gut probiotics inhibits growth of harmful microbes.

·         Modulates & enhance immune system.
The enhanced immune system help maintains a disease-free state

Short-chain fatty acids (SCFAs) protect and strengthen mucosa lining. Without the SCFA (butyrates) for energy, colon cells will die.

·         May reduce intestinal infections

·         Reduced abnormal bacterial leakage through the gut wall when taken in        moderation.

·         Synthesize certain vitamins.

·         Increase mineral absorption, leading to stronger bones and increased bone density.

·         Reduce blood triglyceride level.

·         Better weight & appetite management.

·         Alleviate constipation with improved bowel regularity.

·         Reduced flatulence with lessened or no bad smell.

·         Certain SCFAs can prevent allergy.

·         Epidemiological evidence has shown that dietary fiber is beneficial in the clinical management of obesity, diabetes, cancer, and cardiovascular diseases.

·         Dietary fiber improves short chain fatty acid (SCFAs) production, and reduces glycemic response.

·         Moreover, although glucose may serve as the main metabolic fuel, SCFAs produced by colonic bacterial fermentation of dietary fiber furnish a significant portion of daily energy requirement.

·         Reduce risk of inflammatory diseases such as arthritis, IBS etc. due to anti-inflammatory property.

BOOST IMMUNITY

The gut and immune system form a complex integrated structure that has evolved to provide effective digestion and defence against ingested toxins and pathogens indirectly via a healthy population of symbiotic microbes. [Pathology and Neuroscience, University of Dundee, 2004]

In the gut, prebiotics boost immunity in two ways: through intrinsic properties of its compounds and by favoring growth of beneficial bacteria.

Fermentation by colonic bacteria on the food mass produces gases and short-chain fatty acids. It is these short-chain fatty acids—butyric, lactic, acetic (ethanoic), propionic, and valeric acids that lower the pH of the colon enabling inhibition of pathogens growth.

Microbiota (Bifidobacteria and Lactobacilli) provide a barrier by producing antimicrobial substances and/or stimulating mucosal immunity thus reducing chance of infection (Servin, 2004). 

Lactobacilli not only do not produce carcinogen, it inhibits several bacteria that produce carcinogenic enzymes.

A 2002 study found probiotics also secrete biosurfactants that inhibit infections of surgical implants in rats [Gan et al.]

Prebiotics modify the activities of bacteria that are involved in carcinogenesis through substituting their food source from protein metabolism to carbohydrate metabolism. So when you eat more prebiotic food than protein, you are shifting metabolism of Clostridia and Bacteroides towards more benign end products.

Studies indicated   FOS and Oligosaccharides confer the degree of fermentation selectivity towards Bifidobacteria but could not be utilized efficiently by pathogenic ones such as E-coli, Salmonella, and Helicobacter spp.

Certain types of prebiotics such as β-glucans and oligosaccharides stimulate the immune system by interacting with immune cells and through producing antimicrobial substances in the fermentation process leading to inhibition of pathogenic bacteria.

Researchers have shown that certain types of prebiotics (GOS) can prevent allergy and reduce infectious diseases as well as reduce antibiotic use in infants. Human breast milk naturally contain oligosaccharides and are believed to play an important role in the development of a healthy immune system in infants by increasing the body’s immune cells such as T helper cells, macrophages, and neutrophils.

FOS increases butyrate concentrations in the large intestine; in the liver it plays a role in lipid and glucose homeostasis.  It may destroy colonic cancer by stimulating them to commit suicide (apoptosis).

Researchers found that a class of bacteria called Firmicutes can control candida albicans, a yeast infection. Some people proposed it as a supplement for treating yeast infections.

LOWER DISEASE RISK

Scientists speculated Biomarkers that change with fiber intakes, in particular short chain fatty acids and probiotics may play a role in alleviating digestive and inflammatory conditions such as inflammatory bowel disease, irritable bowel syndrome (IBS), systemic anaphylaxis, arthritis,   rashes, allergic rhinitis and asthma). The lower pH reduces peptide degradation and the resultant formation of toxic compounds such as ammonia and amines which can contribute to aforesaid diseases.

Propionate is a microbial fermentation metabolite that lowers liver production of cholesterol by interfering with its synthesis. This resulted in lower risk for coronary heart disease and lower blood pressure. Water-soluble fibers (beta-glucan, psyllium, pectin) as well as resistant starch (gum Arabic, tara gum, locust bean gum/ carob bean gum) were highly effective for lowering serum LDL cholesterol concentrations, without affecting high density lipoprotein (HDL) concentrations.

Test results on the effect of fiber on diabetes were mixed. A comparison of five week controlled diet using oat beta-glucan (5 g) against barley beta-glucan (5 g or 10 g) showed the oat diet was effective in reduced postprandial glucose and insulin responses whereas the barley diet was not. Large-scale cohort studies indicated insoluble fiber was more effective in reducing risk of developing type II diabetes than soluble fiber.

NUTRITION

Bacteria synthesize B and K Vitamins, which are absorbed through the gut.

Researchers found probiotics Lowers pH in the large intestine, leading to better calcium and magnesium absorption in both animal and human studies.  The higher acidity draws out more minerals from food making them available to move from the gut into the bloodstream. This lead to more efficient absorption of calcium and increased bone density.

Interestingly, your body absorption of calcium only occurs when calcium intake is low or calcium requirement is high. This indicates the prebiotic, inulin, enables your body to absorb the amount of calcium it requires, not more than it needs.

WEIGHT LOSS & OBESITY

Howarth et al estimated that increasing fiber intake by 14 g per day was associated with a 10% decrease in energy intake and a 2 kg weight loss over about a 4-month period. This study was based on analysis of more than 50 other intervention studies. Fiber-rich food gives a sense of fullness (satiety), leading to less food being consumed. A nine week study using wheat dextrin conducted by the Chinese found that a significant decrease in caloric intake was seen from week 2 to the end of the 9 week study for those groups taking dextrin compared to controls.

Studies suggested microbiota in the gut may play a role in controlling obesity. Obese people have more firmicutes than bacteroidetes, while in lean people the bacteroidetes predominate. Tests with germ-free mice found that when these mice had “obese mice microbiota” transplanted into their gut, their total body fat significantly increase than colonization with a 'lean microbiota'. [Turnbaugh et al]

IMPROVE LAXATION

All fibers alleviate constipation. Insoluble fiber give bulk to stools, the water held by the fiber and increased bacterial mass from fermentation contributes to larger and softer stools thus increasing the ease of defecation.