Intestinal bacteria may play a role in motor neurone disease after early studies in animals and humans.
Experiments show that some types of bacteria ̵
The team at the Weizmann Institute in Israel says it adds to the work that the "microbiome" alters the brain in autism and Parkinson's disease.
The research is at a very early stage, but the team hopes that it will provide the first treatments for the disease.
What is a motoneuron disease? The brain and spinal cord do not reach the muscles.
It causes muscle atrophy and impairs the ability to move, eat and even breathe.
The most common form of the disease is Amyotrophic Lateral Sclerosis (ALS), and life expectancy usually begins between two and five years after symptoms begin.
Although physicist Stephen Hawking has lived with a rare form of motor neurone disease for more than half a century.
What is the microbiome?
- They are more microbes than humans – if you count all the cells in your body only 43% are human.
- The rest is our microbiome and includes bacteria, viruses, fungi and unicellular archaea.
- The human genome – the complete genetic guide for a human being – consists of 20,000 statements called genes
- However, when you add up all the genes in our microbiome, there are a number between two million and 20 million microbial genes ,
- It is known as a second genome and associated with diseases such as allergies, obesity and inflammation, bowel disease, Parkinson's, whether anticancer drugs work and even depression and autism
Is it a microbiome?
The experiments described in the journal Nature used mice that were genetically programmed to develop ALS.
The animals' symptoms became much more severe after receiving a dose of antibiotics to kill their intestinal microbiome.
"We were very surprised," said researcher Prof. Eran Elinav, who noted the difference in the muscle and brain tissue of the mice.
The team improved on gut microbes and found 12 species that appeared to exist in diseased mice in much higher or lower numbers.
By adding these bacteria, one after the other, to mice with ALS, the researchers showed that some made the disease more severe.
One kind Akkermansia muciniphila slowed the pace of the disease.
"But in no way do we imply that we stopped, cured or reversed the disease," Prof. Elinav told BBC News.
But how can intestinal bacteria affect the brain?
"The bacteria are in the gut, but the disease is very far from the intestine," said Prof. Elinav.
He added, "Our working hypothesis is this: This is done through the secretion of small molecules that can invade the bloodstream and then into various organs."
Researchers identified a chemical called nicotinamide by Akkermansia muciniphila was produced and that succeeded in injecting into diseased mice improved their condition.
It is believed that the chemical helps to minimize oxidative stress and maintain healthy neuronal function longer.
"It provides a very exciting perspective to understand how our unique microbial signature and function affect processes that are not necessarily where the microbes live," said Prof. Elinav.
Does this happen to humans?
Humans have early-stage work.
37 patients with the disease had blood, microbiome and, in some cases, spinal fluid compared to healthy people with whom they lived.
Again, differences in intestinal microbes and nicotinamide levels in the body were noted.
However, this is the limit of human research, and more trials are planned.
"We can not over-interpret these results," said Prof. Elinav.
"We can not even believe that these results are a new remedy or treatment that people can do at home."
Will this help the patient? A drug that can change the pace of the disease and give people more time.
The Weizmann team does not expect any possibility to prevent or cure motor neuron disease.
Prof. Elinav said, "This is a haunting, devastating disease."
"Doing something to slow ALS is a very important step in a disease we can do little about.
What Do the Experts Think?
"This contributes to a looming, but still blurred, picture of another metabolism that appears to occur in people with ALS," said Dr. Brian Dickie, director of research development for the ALS Motor Neurone Disease Association.
He added, "Nutrition and exercise are also being studied as potential factors associated with the disease."
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