Heat-killed Lactobacillus strain may slash inflammation in healthy overweight people

Heat-killed-Lactobacillus-strain-may-slash-inflammation-in-healthy-overweight-people.jpg
© Getty Images / Lindama (Getty Images/iStockphoto)

Daily supplementation with heat-killed Lactobacillus plantarum L-137 could enhance the response of immune T cells and suppress inflammation in the liver, says a new study from Japan.

Scientists from House Wellness Foods and Kyushu University report that the heat-killed strain, which is the primary ingredient of House Wellness Foods’ Immuno-LP20 product, was also found to reduce cholesterol levels in healthy overweight people.

“The novel finding of this study was that intake of HK L-137 decreased biomarkers of hepatic inflammation,” wrote the researchers in the European Journal of Nutrition. “To our knowledge, this is the first study to show that intake of lactobacilli can reduce [liver enzymes] AST [aspartate transaminase] and ALT [alanine aminotransferase] levels in healthy human subjects.

“It has been reported that slight elevation of serum ALT, even within the normal range, can predict a higher risk of type 2 diabetes, metabolic syndrome, and coronary heart disease. While the reduction of AST and ALT by HK L-137 was within the normal range in this study, these reports suggest that lowering serum ALT within the normal range may reduce the risk of type 2 diabetes, metabolic syndrome, and coronary heart disease.”

Study details

The new study included 100 overweight but healthy men and women (BMI: 23 to 29.9). The participants were randomly assigned to receive either HK L-137 (10 mg) or placebo for 12 weeks.

Results showed that the heat-killed bacteria HK L-137 exerted a significant impact on immune response as gauged by multiple measurements including enhanced Th1-related immune functions, such as concanavalin A (Con A)-induced proliferation in T cell production.

The HK L-137 group also exhibited significantly larger decreases in aspartate aminotransferase and alanine aminotransferase over time compared to the control group.

Total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were also lower in the heat-killed bacteria group, compared to the control group.

In addition, the observed effects were found to be greater in the volunteers with higher C-reactive protein levels (a marker of inflammation).

“HK L-137 improved TC and LDL-C levels in the present study, especially in the subjects with high serum CRP, an indicator of total inflammation induced by endogenous and exogenous stimuli,” wrote the researchers. Inflammation may be linked to higher levels of lipopolysaccharide (LPS) – an endotoxin – leaking from the gut in people with diminished intestinal barrier function.

“Thus, HK L-137 might decrease TC and LDL-C levels by improving the intestinal epithelial barrier function and inhibiting the translocation of endotoxin.”

The researchers concluded: “It is possible that HK L-137 may be useful for prevention/treatment of metabolic dysfunction in persons at risk of inflammation.”

Source: European Journal of Nutrition

Published online ahead of print, doi: 10.1007/s00394-019-02112-3

“Daily intake of heat-killed Lactobacillus plantarum L-137 improves inflammation and lipid metabolism in overweight healthy adults: a randomized-controlled trial”

Authors: Y. Tanaka et al.