Exploring the Partnership Between
You and Your Belly
Joanna Wilson, D.O.
Women’s Health
Board-Certified Internal Medicine

-Bonnie Bassler (TED talk)
“HUMANS ARE 99% BACTERIAL.”

• Humans have 10 X more bacterial cells than human cells
• Between 300-1000 species live in our intestines
– 99% are anaerobes
• Intestinal bacteria have allowed us to obtain greater nutrients from our food, develop sophisticated immune systems, and the balance affects cognition and emotions

• Vaginal flora changes during pregnancy to bacteria which are better able to metabolize breast milk
• Bacteria introduced during vaginal delivery to germ-free babies establishes the baby’s intestinal ecosystem

• Intestinal bacterial ecosystem introduced to babies born by Csection resembles skin flora of birth participants

Breast Milk is the original pre- and probiotic!
Breast milk contains over 600 different kinds of bacteria and it provides oligosaccharides to feed the bacteria in the baby’s intestine.
Yum!

Colon Bacteria: Functions in Nutrition
• Improve acquisitions of vitamins and nutrients from food
– Germ-free rodents required 30% more calories to maintain weight
– Malnutrition can occur after antibiotic use
• Affect cholesterol metabolism
• Generate vitamins B1, B7, K

• The dominant microbiota is established in infancy and inhibits colonization by pathogens by
– Occupying luminal cell receptors
– Releasing bacteriostatic and microbicidally acting substances

Colon Bacteria: Function in Immunity
• Assist in establishment of self vs non-self recognition
– Germ-free mice have higher numbers of natural-killer cells, with resultant increase in asthma and IBD
• Mediate activity of the immune cells of the colon lining and control the intestinal lining permeability
• Communicate with spleen and liver to control immune cell response

Abnormal Immune Response to
Gastrointestinal Bacteria May
Contribute to Diseases
• Autoimmune Diabetes I
• Crohn’s Disease
• Ulcerative Colitis

Societal Behaviors Impact Future
Disease
• The drastic increase of children born without h. pylori gastric bacteria correlates very strongly with the increase in incidence of allergies and asthma in children
• Children born by C-section have a higher rate of allergies and asthma

• 40 genes for learning, memory, mood, and motor control are permanently affected by the early presence of gut bacteria
• Timing is everything
– Bacteria must be established early in life for benefits to occur

• Several studies showed germ-free mice who were inoculated with specific bacteria generated and delivered neurotransmitters to the brain, affecting anxiety, corticosteroid production, and colitis symptoms
• Human studies using yogurt with probiotics showed emotion and sensitivity were statistically different when probiotics were consumed

Colon Bacteria Alter Pain Perception
• Pain perception was reduced in rats with
Bifidobacterium infantis inoculation
• Lactobacillus acidophilus induced opiod and cannabinoid receptors in intestinal epithelial cells

Bidirectional Communication Methods
• Vagus (10 th cranial nerve)
• Bloodstream (cytokines, hormones, neuropeptides)
• Spinal cord
• Allow for near-instant reaction to acute change in gut environment

Neurotransmitters are Highly
Preserved in Nature
Greatest concentration of serotonin is the intestines!

Bacteria Neurotransmitter Produced
Lactobacillus, Bifidobacterium GABA
Norepinephrine Escherichia, Bacillus,
Saccharomyces
Streptococcus, Escherichia,
Enterococcus
Bacillus, Serratia
Lactobacillus
Serotonin
Dopamine
Acetylcholine

• Stress increases permeability of the gut lining to bacteria and bacterial antigens
– Activates immune response
– Changes the composition of the gut microbiome
– Alters brain neurochemicals
– Ex: inflammation promotes
E. coli proliferation

Highly Processed Diets Modify Colon
Bacteria
• Sugar/sugar substitutes
• High-fructose corn syrup
• Preservatives
• Processed grains
• Alcohol
• Appear to be either non-nutritive or harmful to gut flora

• Isoflavones for menopause symptoms changed bacterial diversity and composition
• L-carnitine for muscle gain induces colon bacteria which convert it into a substance which causes atherosclerosis
– The same manner as a high red meat diet does

Age and Sex Differences in Colon
Bacteria
• Aging causes:
– Reduction in anaerobes and bifidobacteria
– Increase in Enterobacter and endotoxin-producing gram negative bacteria
• Stool pH is higher in women (less acidic)

Effect of Occupation on Colon Bacteria
• Ranchers harbored more Prevotella species
– Abundant in cattle and sheep

• 1. Bacteroides- induced by a diet high in animal protein, amino acids, and saturated fats
• 2. Prevotella- induced by a diet high in carbs/sugars
• 3. Ruminococcus

An Individual’s Microbiota is Generally
Consistent Through Life
• Foundation colonies tend to be consistent over a person’s life
• About 40% of bacterial types are transient and affected by diet, lifestyle, meds

Leanness, Bacteria Type, and Calorie
Absorption
Lean
Bacteroidetes
Lower energy absorption
Obese
Fermicutes
Higher energy absorption

Effects of Diabetes and Obesity on
Colon Bacteria
• 26 Species of bacteria correlated significantly with obesity, insulin resistance, and metabolic syndrome
• Bacteria from obese people had relatively higher production of short chain fatty acids
– Increased production of leptin
• Increases appetite

• Inoculation of genetically thin mice with enterobacter cloacae caused weight gain

Fat to Thin
• Gastric Bypass Surgery
Alters Gut Flora
– Fecal samples from bypassed colonized mice to sterile non-surgerized mice caused significant weight loss in recipients

• Using bacterial flora to change nutrient metabolism and inflammation
– Changing to a lower fat/ lower carb diet
– Human stool transplants from lean donors

Strain Human Data
L. rhamnosus GG Immune enhancement, infectious diarrhoea in children, primary prevention of atopic dermatitis
B. lactis BB-12
L. reuteri SD2112
Immune enhancement, diarrhoea in children
Reduced absences from work, diarrhoea, immune function
B. infantis 35624
L. casei DN114-001
B. longum BB536
L. acidophilus NCFM
B. lactis HN019 (DR10)
B. animalis DN173-010
L. plantarum 299V
Lactobacillus casei Shirota YIT9029
L. salivarius UCC118
L. johnsonii La1 (Lj1)
Escherichia coli Nissle 1917
Saccharomyces cerevisiae (boulardii) lyo
S. thermophilus (most strains)
Irritable bowel syndrome (IBS)
Immune enhancement
Allergy symptoms, intestinal micro-ecology
Symptoms of lactose intolerance, reduced small-bowel bacterial overgrowth
Immune enhancement, especially in elderly
Normalizes intestinal transit time
IBS, post-surgical gut nutrition
Superficial bladder-cancer recurrence, intestinal microbiota, immune enhancement
Inflammatory bowel disease
Immune function, Helicobacter pylori eradication
Immune function, intestinal health
Antibiotic-associated diarrhoea, Clostridium difficile infections
Symptoms of lactose intolerance

• Probiotics are live microorganisms which, when administered in adequate amount, confer a health benefit on the host
– Not all strains confer the same benefits
– Colony Forming Units (CFU) dose varies for effectiveness
– Bacteria must be able to survive ingestion
– The effect of a probiotic is likely site-specific in the colon
– Sauerkraut, kimchi, pickles, yogurt, kefir, miso
(nonpasturized)
– May not have long-term impact without significant diet change

• Selectively fermented ingredient that results in specific changes in the composition and/or activity of the gastrointestinal microbiota, thus conferring benefit(s) upon host health
– Resistance to degradation by the host
– Fermentation by intestinal microbes
– Stimulate growth or activity of intestinal microorganisms
– Breast milk, leek, asparagus, Jerusalem artichoke, artichoke, garlic, onion, wheat, oat, soybean, bran, psyllium
– Fructooligosaccharides (FOS), galactooligosaccharides
(GOS)

New Products May Encourage Residence of
“Good Bacteria”

• Highly effective in resistant C. difficile colitis
• Safe and inexpensive

Future Uses Of Colon Bacteria To
Improve Health
• Create intestinal bacteria which promote endocrine functions, like insulin production
• Produce highly selective, nonabsorbable antibiotics
• Invent drugs to alter bacteriato-bacteria communication
• Understand probiotics to manipulate health and disease
• Transplant stool from thin people for treatment of obesity
• Improve nutrient absorption to end starvation