Left Menu
Development News Edition

Is KLE1738 human gut bacteria responsible for depression?


Is KLE1738 human gut bacteria responsible for depression?
KLE1738 had previously appeared on the ‘most wanted list’ of the National Institutes of Health, meaning that it had yet to be cultured, despite its relative prevalence in the human gut. Image Credit: Pixabay

A team of researchers has studied a compelling link between one of NIH's 'most wanted' bacteria and mental health. The researchers have established a correlation between depression and a group of neurotransmitter-producing bacteria found in the human gut.

The research team from the U.S. Department of Energy's (DOE) Argonne National Laboratory, Northeastern University and elsewhere made the connection by first isolating the KLE1738, a bacterium that has a surprising dependency upon a brain chemical called gamma-aminobutyric acid (GABA).

"The association of microbial GABAmetabolism with mental health is highly compelling. The general ability of the microbiome to produce and/or consume GABA has not been as broadly described before, and a bacterium dependent on GABAhas never been reported," said Jack Gilbert, group leader for microbial ecology at Argonne who also holds new faculty appointments at the University of California, San Diego, in the Department of Paediatrics and at Scripps Institution of Oceanography.

"Because of its unique growth requirements, nobody else has reported growing KLE1738," opined Philip Strandwitz, the article's lead author and a postdoctoral research associate at Northeastern University's Antimicrobial Discovery Center. Strandwitz and his colleagues have proposed the name Evtepia gabavorous for KLE1738. They will more fully describe the bacterium in a future publication.

"The association of microbial GABA metabolism [the brain protein gamma-aminobutyric acid (GABA)] with mental health is highly compelling," Jack Gilbert, Argonne microbial ecologist.

KLE1738 had previously appeared on the 'most wanted list' of the National Institutes of Health, meaning that it had yet to be cultured, despite its relative prevalence in the human gut. The bacterium has been detected in nearly 20 percent of the human gut microbiomes available in the Integrated Microbial Next Generation Sequencing Database. Gut microbiota, the entire collection of microorganisms found in that habitat, affect many important functions, including the immune response and the nervous system. Nevertheless, many microorganisims residing in the human gut remain uncultured, which the research team called 'an obstacle for understanding their biological roles' in the Nature Microbiology article.

More such microorganisms probably remain uncultured because they require key growth factors that are provided by neighboring bacteria in their natural environments, but not under artificial laboratory conditions. During an extensive screening process, the team found that KLE1738 required the presence of Bacteroides fragilis, a common human gut bacterium, to grow.

Further biological testing and purification led to the isolation of GABA as the growth factor produced by Bacteroides fragilis. GABA was, in fact, the only nutrient tested during the experiments that supported the growth of KLE1738. In the next research phase, the team explored the possible connection between Bacteroides and depression. Stool samples and functional magnetic resonance imaging measurements of brain activity were collected from 23 subjects suffering from clinically diagnosed depression.

The researchers found an inverse relationship between the relative abundance of fecal Bacteroides and functional connectivity in a part of the brain associated with elevated activity during depression. This means that low abundance of Bacteroides was associated with high activity in that part of the brain, and vice versa.

"A good first step is to repeat our findings in additional human cohorts, which we are actively exploring. When it comes to depression, animal models are often difficult to translate, which is why we are so excited about human studies," said Strandwitz of further research.

Recent work published in the journals Science and Cell have identified the presence of sensory neurons in the gut that are hard-wired to the brain. "It would be great to explore whether microbial GABA can act as a signal via that pathway," said Anukriti Sharma, a co-author of the Nature Microbiology article and a postdoctoral scholar at Argonne.

Strandwitz and co-author Kim Lewis, a distinguished university professor at Northeastern, have founded a biotechnology company, Holobiome, to develop microbiome-based therapeutics that target diseases of the nervous system. Gilbert is a member of the company's scientific advisory board. Additional research will be needed, however, before it may become possible to develop a treatment for people suffering from depression.

Download The Devdiscourse News App for Latest News.


TRENDING

OPINION/BLOG/INTERVIEW

Conspiracy theories on COVID 19: Legislators, Scientists, and Journalists all joined the Caravan

Conspiracy theories are not new for virus epidemics. There have been conspiracy theories on HIV-AIDS, Polio Vaccines, Ebola Virus, and several other diseases as well. However, what makes the 2019 Novel Coronavirus different from others is ...

Top 10 Fake News, Myths and Realities on 2019 Novel Coronavirus COVID 19

With nearly 1500 deaths by January 14 and around 65,000 infections in China, the Novel Coronavirus 2019 has become one of the worst health epidemics of the 21st Century. However, 8,573 people have been cured but the rumor mongers are a...

Handling fake news Infodemic in time of Coronavirus epidemic

Social media has provided a platform where everybody can disseminate his her views without any supervision. Its excellent if the message is genuine but misinformation is equally disastrous. Health is such a topic where every Tom and Harry c...

Sentiment Analysis on Budget 2020: Long shot for solution to economic worries?

Industries and individuals alike had high expectations from the government to take tangible steps but the budget 2020 seems to have failed expectations....

Videos

Latest News

UPDATE 2-Prime minister leaves Lesotho, avoids being charged with murdering wife

Lesotho Prime Minister Thomas Thabane left the country, skipping a court appearance on Friday at which he was expected to be charged with murdering his estranged wife.Thabane, 80, had been due in court at 9 a.m. 0700 GMT over the death of L...

US News Roundup: Trump adviser Stone to be sentenced; Trump blasts best-picture Oscar for South Korean film 'Parasite' and more

Following is a summary of current US domestic news briefs.Bloomberg presidential campaign reports 409 million in total spending so farU.S. Democratic presidential candidate Michael Bloombergs campaign spent 409 million through January, with...

More than 6,000 saints arrive in Kathmandu to observe Mahashivaratri

More than 6,000 saints, including from India, have arrived in Kathmandu for offering prayers at the famed Pashupatinath Temple on Friday on the occasion of Mahashivaratri, the festival dedicated to Lord Shiva. All four entrances of the temp...

Gopal Rai visits air quality monitoring station set up in association with Washington University

Delhi Environment Minister Gopal Rai on Friday visited an air quality monitoring station established in association with Washington University for undertaking real-time source apportionment study. Talking to reporters during his visit to th...

Give Feedback