This Heritable Gut Bacterium Is A Robust Health Marker

Shin Jie Yong

Christensenella is patented for good reasons. But will it live up to its expectations?
Image from Pixabay

Christensenellaceae — a resident of the human gut microbiome — is another reason why microbes, genetics, metabolism, and health are intricately intertwined.

An October 2019 review by Jillian Waters and Ruth Ley — from the Department of Microbiome Science, Max Planck Institute for Developmental Biology, Germany — summarized existing research on Christensenellaceae. Findings to date have been astonishing, earning its name as a unique, heritable gut bacterium with distinct properties.

1. Heritability

Analyzing genomics data from 4 large sample size studies, Waters and Ley estimated that host genetics determine 30–60% of Christensenellaceae abundance in the gut, which is unusually high by microbiome standards.

“Of the hundreds of taxa in the gut, the family Christensenellaceae is consistently identified as among the most highly heritable,” they explained.

Heritability refers to what extent the host genetics predisposes one for a certain quantitative trait. “Height is heritable because this trait is largely genetically determined,” Waters and Ley gave an example. “Individuals are genetically predisposed to harbor a high or low relative abundance of these bacteria may be a generalizable human trait.”

Waters and Ley, however, cautioned that “heritability calculations take into account quantitative measures of the trait (such as relative abundance) and should not be confused with whether the Christensenellaceae are inherited (i.e., vertically transmitted) from family members, which is not known.”

“It could be one of the mechanisms for genetic inheritance of disease — a route we haven’t thought of before. Everyone has a small amount of it, around 1% but some people have as much as 10%,” comments Tim Spector from Kings College London and a pioneer in the heritability of Christensenellaceae.

“We think the more you have, the more protected you are against obesity,” Spector continued.

2. Longevity

Waters and Ley cited 4 studies detailing that the gut of centenarians and supercentenarians harbor higher abundances of Christensenellaceae than the younger controls in China, Korea, and Italy. They further compiled 6 studies showing the association between Christensenellaceae and longevity in Korea, United States, United Kingdom, Nigeria, and Canada.

They do have doubts, however, arguing that “dietary patterns that vary by age may influence this association, or individuals born earlier may have always harbored greater levels of Christensenellaceae compared to those born later.”
Image from Freepik

3. Leanness

If Christensenellaceae and longevity are connected, what is the middleman? In actuality, researchers first discovered the robust relationship between Christensenellaceae abundance and healthy BMI before longevity. And that Christensenellaceae was nearly non-existent in obese individuals.

“Since this initial observation, the association of Christensenellaceae with a normal BMI has been corroborated repeatedly in populations from a number of countries that included adult men and women of various ages,” adds Waters and Ley after summarizing 13 relevant studies.

To demonstrate causality, scientists have transferred the gut microbiota of obese individuals with nill levels of Christensenellaceae into germ-free mice. These mice soon became obese, as expected. But this can be prevented with an additional gut transplant of Christensenella minuta, despite maintaining the same diet.

4. Metabolic Health

Apart from BMI, Waters and Ley also cited research demonstrating that Christensenellaceae abundance is linked to:

  1. Low triglyceride levels
  2. Low belly fat
  3. Low LDL (‘bad cholesterol’)
  4. High HDL (‘good cholesterol’)
  5. Efficient glucose metabolism
  6. Increased intake of fruits and vegetables
  7. Omnivorous diet rather than vegetarians
  8. Dairy consumption
  9. Increased animal products
  10. Protein metabolism
“Taken together, these studies indicate that the association of Christensenellaceae with health parameters may in part be due to its association with a diet high in protein and fiber,” continues Waters and Ley.
Image from Freepik

5. Gut Health

Italian researchers from the Laboratory of Probiogenomics and Microbiome Research Hub re-analyze 3048 public datasets from sufferers of gut disorders such as ulcerative colitis, colorectal cancer, Crohn’s disease, etc. The derived conclusion was that Christensenellaceae is one of the five bacterial taxa qualified as a biomarker of gut health. Following this reasoning, Christensenellaceae depletion is widely apparent in victims of gut disorders.

Christensenella is Patented

In 2019, LNC Therapeutics — a French biotech company specializing in gut microbiome-based drugs — recently made a license agreement with Cornell Univesity for the patent of Christensenella to treat metabolic diseases.

“Scientific data showed that the absence of Christensenella was highly associated with human patients with obesity as well as some inflammatory, metabolic and other diseases,” says Dr. Georges Rawadi, CEO of LNC Therapeutics. “Through our own activity at LNC, we also made this link and filed patents in that space. If all goes well with Christensenella then we are looking at the horizon of 2027–2028 to get a product out there,” adds Rawadi.

Will Christensenella be a Cure-All?

We know that the gut microbiome is the cornerstone to health as it influences 12 different distant organs. Still, it is unlikely a single gut bacterium can be a panacea. Microbiome science still has many unknowns as I’ve written here: Gut Microbiota: An Entity That Connects to Distant Organs.

One is that we still don’t know how to culture the majority of gut bacteria inside us. Because some gut bacteria require fine-tuned environmental conditions to support their growth; some needs the presence of other bacterial species; some need growth signals from the complex food metabolism inside our gut; etc. Our known human gut microbial diversity has only been recently extended by 281% in 2019. And we don’t know what functions they perform.

Who knows if Christensenella needs other requirements to fulfill its potential? If that’s the case, probiotics with Christensenella only would likely disappoint.

“We have to be careful not to assume that all we need to do to reduce obesity is add some Christensenella,” to patients’ guts,” asserts Professor Emma Allen-Vercoe at the University of Guelph in Ontario, Canada.

This article was originally published in Microbial Instincts with minor modifications.

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MSc Biology | 7x first-author academic papers | 250+ articles on coronavirus | Freelance medical writer


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