Strain-Specific Effects of Bifidobacterium longum on Hypercholesterolemic Rats and Potential Mechanisms

Abstract

Hypercholesterolemia is an independent risk factor of cardiovascular disease, which is among the major causes of death worldwide. The aim of this study was to explore whether Bifidobacterium longum strains exerted intra-species differences in cholesterol-lowering effects in hypercholesterolemic rats and to investigate the potential mechanisms. SD rats underwent gavage with each B. longum strain (CCFM 1077, I3, J3 and B3) daily for 28 days. B. longum CCFM 1077 exerted the most potent cholesterol-lowering effect, followed by B. longum I3 and B3, whereas B. longum B3 had no effect in alleviating hypercholesterolemia. Divergent alleviation of different B. longum strains on hypercholesterolemia can be attributed to the differences in bile salt deconjugation ability and cholesterol assimilation ability in vitro. By 16S rRNA metagenomics analysis, the relative abundance of beneficial genus increased in the B. longum CCFM 1077 treatment group. The expression of key genes involved in cholesterol metabolism were also altered after the B. longum CCFM 1077 treatment. In conclusion, B. longum exhibits strain-specific effects in the alleviation of hypercholesterolemia, mainly due to differences in bacterial characteristics, bile salt deconjugation ability, cholesterol assimilation ability, expressions of key genes involved in cholesterol metabolism and alterations of gut microbiota.

In vivo Trial of Bifidobacterium longum Revealed the Complex Network Correlations Between Gut Microbiota and Health Promotional Effects

“…Experimental determination of bile salt deconjugation and cholesterol assimilation activities with four different B. longum strains (CCFM 1077, I3, J3, and B3) from the elderly showed strain specificity in vitro, suggesting that B. longum has two different cholesterol reduction mechanisms, bile salt deconjugation by bile salt hydrolase and/or cholesterol assimilation by specific absorption as mentioned previously. To evaluate them, each B. longum strain was administrated to a high-cholesterol diet rat model which revealed in vivo cholesterol reduction from 27% to 44% supporting these mechanisms (Jiang et al, 2021). Interestingly, the administration of B. longum CCFM1077 to the rat model showed the highest cholesterol reduction activity because it has both bile salt hydrolase and cholesterol assimilation activities.…”

Probiotics Interact With Lipids Metabolism and Affect Gut Health

“…With the in-depth study of the gut microbiota, more and more attention has been paid to probiotics. There are many types of probiotics isolated from various environments, such as Bifidobacterium , Lactobacillus , and Bacteroides , which can be involved in lipid metabolism in direct and indirect ways ( 7 , 8 , 42 , 73 , 74 ). Therefore, we mainly summarized the probiotics involved in lipid metabolism through cholesterol metabolism, short-chain fatty acids (SCFAs), interaction with gut microbiota to reduce oxidative damage and improve intestinal barrier.…”

The metabolic mechanism of growth inhibition by co-culture of Bacteroides xylanisolvens Y-11 and Bifidobacterium longum y37

“…Bifidobacterium longum is the most abundant Bifidobacterium in the human intestine (Rinninella et al, 2019), especially in the feces of infants, accounting for about 69.96% (LEE et al, 2015). It has been reported to have a wide range of probiotic functions, including allergy inhibition (Xiao et al, 2006), cholesterol reduction (Andrade and Borges, 2009, Jiang et al, 2021, Bordoni et al, 2013, improvement of skin health (Wong et al, 2019) and human health (Takahashi et al, 2006, Akatsu et al, 2012, and prevention of intestinal diseases (Akatsu et al, 2012, Yao et al, 2021. The sugar metabolism in Bifidobacterium spp.…”