Meat, dairy and plant proteins alter bacterial composition of rat gut bacteria

Abstract

Long-term consumption of red meat has been considered a potential risk to gut health, but this is based on clinic investigations, excessive intake of fat, heme and some injurious compounds formed during cooking or additions to processed meat products. Whether intake of red meat protein affects gut bacteria and the health of the host remains unclear. In this work, we compared the composition of gut bacteria in the caecum, by sequencing the V4-V5 region of 16S ribosomal RNA gene, obtained from rats fed with proteins from red meat (beef and pork), white meat (chicken and fish) and other sources (casein and soy). The results showed significant differences in profiles of gut bacteria between the six diet groups. Rats fed with meat proteins had a similar overall structure of caecal bacterial communities separated from those fed non-meat proteins. The beneficial genus Lactobacillus was higher in the white meat than in the red meat or non-meat protein groups. Also, rats fed with meat proteins and casein had significantly lower levels of lipopolysaccharide-binding proteins, suggesting that the intake of meat proteins may maintain a more balanced composition of gut bacteria, thereby reducing the antigen load and inflammatory response in the host.

Dietary Keratan Sulfate from Shark Cartilage Modulates Gut Microbiota and Increases the Abundance of Lactobacillus spp.

“…Lipopolysaccharide (LPS) is an endotoxin that is only produced by Gram-negative bacteria, which, once entered the circulation system, can stimulate inflammation with the most potent capability [59,60]. Similarly, Gram-positive bacteria could also produce antigens that would cause side effects on host immunity [59,60].…”

“…Lipopolysaccharide (LPS) is an endotoxin that is only produced by Gram-negative bacteria, which, once entered the circulation system, can stimulate inflammation with the most potent capability [59,60]. Similarly, Gram-positive bacteria could also produce antigens that would cause side effects on host immunity [59,60]. As an acute phase protein that specifically binds to LPS and antigens from Gram-positive bacteria, LPS-binding protein (LBP) represents a perfect biomarker for antigen load from the gut microbiota and inflammatory response in the host [30,59,60].…”

“…Similarly, Gram-positive bacteria could also produce antigens that would cause side effects on host immunity [59,60]. As an acute phase protein that specifically binds to LPS and antigens from Gram-positive bacteria, LPS-binding protein (LBP) represents a perfect biomarker for antigen load from the gut microbiota and inflammatory response in the host [30,59,60]. Hence, to give an overall evaluation on potential harmful effect of KS during modulation of gut microbiota, the serum LBP levels in different groups of mice were determined.…”

“…Quality control of the raw sequencing data was performed by QIIME (version 1.17) using the criteria previously described [60]. The Operational Taxonomic Units (OTUs) were clustered using UPARSE (version 7.1) pipeline [60].…”

“…The Operational Taxonomic Units (OTUs) were clustered using UPARSE (version 7.1) pipeline [60]. The Venn diagram was constructed using R packages (version 3.1.0, R Core Team, Auckland, New Zealand) to compare the compositional OTUs in the gut microbiota of different groups.…”