You may have the same microbiome as your mother’s mother’s mother’s mother’s … mother
To learn more about the gut microbiome, researchers used mice from two locations in the US and Canada. They set up housing for the mice in their test facility and the mice from each location were kept separate from the other. The researchers allowed the mice to produce young, and the offspring were allowed to produce offspring.
This took three years, resulting in 11 generations of mice. During this process, the researchers took gut samples that were subjected to genetic testing to identify the bacteria living in the gut.
The researchers found that the gut microbiome of the mice remained remarkably stable—the biome of the 11th generation was nearly identical to the first generation. The researchers suggest this is evidence of gut microbiome bacteria being passed down through the generations, an example of vertical transmission.
It was noticed that in the few instances where new bacteria were introduced into a mouse’s gut from an unknown external source, the bacteria were of types that tend to cause illnesses. This suggests that harmful bacteria that show up in the gut probably come from a horizontal source.
These findings suggest mammals and their gut biomes have co-evolved in a way that led to symbiosis, which is the interaction between two different organisms living in close physical association, typically to the advantage of both. The research concluded by suggesting that evolutionary theory indicates their findings likely apply to humans as well.
Suffering from ANXIETY, it’s your microbiome….
What are the mechanisms that cause the possible link between gut microbiome and anxiety?
A study at the APC Microbiome Institute at University College Cork helped to bring this problem into mainstream knowledge.
Researchers analyzed groups of mice that had three different gut microbiome conditions:
Germ-free mice, which had no gut microbiome due to being bred in an environment free of microorganisms.
Ex germ-free mice, which had been colonized with gut microbiome later on.
Mice with the normal gut microbiome, bred in their usual conditions.
The team found that mice bred in germ-free conditions developed symptoms of anxiety, depression, problems with sociability, and cognitive dysfunctions.
The study looked at how the absence of gut microbiome affected miRNAs in the rodents’ brains. miRNAs are tiny RNA molecules that regulate gene expression.
The research sought to locate miRNAs in the amygdala and prefrontal cortex of the mice in each gut bacteria condition.
The research found that the germ-free mice showed differences in 103 miRNAs in the amygdala, the brain region involved in emotional processing – and 31 changes in miRNAs in the prefrontal cortex – the brain region involved in behavior, planning, and impulse control.
When the researchers introduced bacteria to the guts of the germ-free mice in later life, some of the differences in miRNAs within the amygdala and the prefrontal cortex disappeared.