by Sarah A LoBisco, ND
This week’s blog highlights the connection between our gut’s critter population
to our health. The microflora that resides in our intestines outnumbers our
cells for a reason! They are critical regulators on how our body runs.
This week we are going to look at the impact of our gut bugs on:
1. Our
risk for metabolic syndrome
2. Inflammation
3. Brain
and Mood
Read more about these little microbes below:
Gut Micoflora relates to
Metabolic Functions
A recent study demonstrated that the type of bugs resident in your
intestines determines the risk for metabolic syndrome. This is a syndrome
that consists of:
·Elevated blood sugar (glucose of 100 mg/dl or
higher)
·High triglycerides (150 mg/dl or higher)
·Low HDL (under 50 mg/dl for women, 40 mg/dl
for men)
·Weight gain (increased fat around the middle-as
measured by waist circumference)
·Elevated blood pressure (130/85 mmHg or
higher)
According to the study:
Obesity has
been linked to the human gut microbiota; however, the contribution of gut
bacterial species to the obese phenotype remains controversial because of
conflicting results from studies in different populations. To explore the
possible dysbiosis of gut microbiota in obesity and its metabolic
complications, we studied men and women over a range of body mass indices from
the Old Order Amish sect, a culturally homogeneous Caucasian population of
Central European ancestry. We characterized the gut microbiota in 310 subjects
by deep pyrosequencing of bar-coded PCR amplicons from the V1-V3 region of the
16S rRNA gene. Three communities of interacting bacteria were identified in the
gut microbiota, analogous to previously identified gut enterotypes. Neither BMI
nor any metabolic syndrome trait was associated with a particular gut
community. Network analysis identified twenty-two bacterial species and four
OTUs that were either positively or inversely correlated with metabolic
syndrome traits, suggesting that certain members of the gut microbiota may play
a role in these metabolic derangements.
Sources:
Pub Med Health. Metabolic syndrome: Insulin resistance
syndrome; Syndrome X. June 2, 2012. ADAM 2012. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004546/
Inflammation, Gut, & Mice
Here’s some evidence that immunity and inflammation are also related to
the gut!
The study reads:
Key to the
studies were IL10-/- mice, a mouse model that is genetically prone to gut
inflammation because it is bred to lack a gene that suppresses the inflammatory
response. Using a technique that allows researchers to identify bacterial
varieties by examining variants in a specific gene (16S rRNA), the team
compared bacterial communities in the inflamed guts of IL10-/- mice with those
in healthy normal (“wild type”) mice. They found that the diversity of
different kinds of bacteria was significantly lower in the mice with
genetically-facilitated inflammation. Among the IL10-/- mice, however, the team
found little difference in microbial diversity between mice that simply had
inflammation and those that also had cancer, indicating the inflammation was
the critical factor affecting microbe populations.
“A shift in
the microbial community is associated with inflammation,” Fodor noted. “It is
interesting that the microbial community is actually changing with the disease
state, which indicates that it is either responding to or contributing to the
disease state.” Despite the
overall drop in diversity, the team found that the presence of E. coli was markedly increased
(by a factor of 100) by inflammation.
Source: Hathaway, J. Mouse study finds clear
linkages between inflammation, bacterial communities and cancer. EurekAltert.
August 16 2012.
http://www.eurekalert.org/pub_releases/2012-08/uonc-msf081212.php .
Gut Microflora relates to Brain
Function
Now, onto the gut-brain connection. Here’s a study demonstrated
that anxiety behavior in mice related to a non-supportive microflora:
Key Results Germ-free mice, compared to SPF mice,
exhibited basal behavior in the EPM that can be interpreted as anxiolytic.
Altered GF behavior was accompanied by a decrease in the N-methyl-D-aspartate
receptor subunit NR2B mRNA expression in the central amygdala, increased
brain-derived neurotrophic factor expression and decreased serotonin receptor
1A (5HT1A) expression in the dentate granule layer of the hippocampus.
We conclude
that the presence or absence of conventional intestinal microbiota influences
the development of behavior, and is accompanied by neurochemical changes in the
brain.
Source: Neufeld, K. M., Kang, N.,
Bienenstock, J. and Foster, J. A. (2011), Reduced anxiety-like behavior and
central neurochemical change in germ-free mice. Neurogastroenterology &
Motility, 23: 255-e119. doi: 10.1111/j.1365-2982.2010.01620.x
Final thoughts:
In summary, your “gut bugs” have an impact on lipid profiles, heart health, immune
signaling, and brain chemicals! Lifestyle factors such as eating lots of
processed foods, toxicant exposures, pollutants, sugar, and certain drugs all
affect the ratio of microflora in your belly negatively.
Changing to a healthy diet and doing supportive measures (such as supplementing
with fermented foods or probiotics) and avoiding food sensitivities have health
effects beyond the absence of gas, bloating, and icky poop! After all, these
things affect the little critters which modulate our whole body’s functioning!
