Researchers at Wake Forest School of Medicine (in North Carolina), have discovered that using inactivated (dead via the application of heat) Lactobacillus paracasei (derived from humans) appears to have a remarkably beneficial effect in an animal model of leaky gut, thereby reducing inflammation.[i] In doing so, they significantly extended the lives of C. elegans, a roundworm frequently used in laboratory experiments. They then tested the inactivated bacteria on elderly mice, finding that it “…helped prevent the development of metabolic dysfunctions that a high fat diet causes. It also improved gut permeability, making leakages less likely, reducing inflammation, and boosting cognitive function…”[ii]
If you a regular reader of this blog, you will remember that leaky gut is a major factor in inflammatory diseases. For those unfamiliar, this is a condition in which inflammation leads to the mucus lining of the intestines becoming permeable, allowing bacteria, toxin metabolites of bacteria and yeast, undigested food, etc. to make their way into the blood stream. Leaky gut is also a natural result of the aging process: the gut becomes increasingly permeable and while a result of inflammation, it is also a major cause, increasing the risks of developing illnesses like obesity, diabetes, cardiovascular illness, Alzheimer’s and other cognitive problems, and many more.
The scientists discovered that it is a component of this bacteria’s cell wall (lipoteichoic acid) which led to the health improvements in the animals. This is not the first time an inactivated bacterial strain has been shown to have major health benefits. Many of you may remember that back in July of this year for one, I wrote about using inactivated Akkermansia to treat the development of fat (i.e. obesity) and insulin resistance. In that case, a 3 month long, double-blind, randomized trial in human showed that heat-killed Akkermansia “…helps to limit the increase of different cardiovascular risk factors in subjects who are overweight and obese.” Again, the researchers believe that it is a component of the cell wall which has the beneficial effect.
This story gets even more interesting. The Wake Forest scientists discovered that this inactivated species “…significantly increases mucin production, and proportionately, the abundance of mucin-degrading bacteria Akkermansia muciniphila also increases.” (Mucin is a component of mucus. Thus, increasing the food supply leads to an increase on probiotic species that thrive on that substance.) Likely then, the L. paracasei is exerting its beneficial effects both directly (i.e. it’s cell wall) and indirectly, by boosting levels of other beneficial probiotic species.
Considering the importance of finding effective treatments for leaky gut, this is very promising. This has obviously not as yet been tested in humans but the lead researcher has applied for a patent for the product. I’ll keep an eye out for any further news.
[i] Wang, et. al. Lipoteichoic acid from the cell wall of a heat killed Lactobacillus paracasei D3-5 ameliorates aging-related leaky gut, inflammation and improves physical and cognitive functions: from C. elegans to mice. GeroScience. 2019. https://doi.org/10.1007/s11357-019-00137-4