Lactobacillus rhamnosus BFE 5264 and Lactobacillus plantarum NR74 Promote Cholesterol Excretion Through the Up-Regulation of ABCG5/8 in Caco-2 Cells

Abstract

The effect of two putative probiotic strains, Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74, on the control of cholesterol efflux in enterocytes was assessed by focusing on the promotion of ATP-binding cassette sub-family G members 5 and 8 (ABCG5 and ABCG8). Differentiated Caco-2 enterocytes were treated with live bacteria, heat-killed bacteria, a bacterial cell wall fraction, and metabolites and were subjected to cholesterol uptake assay, mRNA analysis, and protein analyses. Following LXR-transfection by incubation with CHO-K1 cells in DNA-lipofectin added media, the luciferase assay was conducted for LXR analysis. Treatment of Caco-2 cells with L. rhamnosus BFE5264 (isolated from traditional fermented Maasai milk) and L. plantarum NR74 (isolated from Korean kimchi) resulted in the up-regulation of LXR, concomitantly with the elevated expression of ABCG5 and ABCG8. This was associated with the promotion of cholesterol efflux at significantly higher levels compared to the positive control strain L. rhamnosus GG (LGG). The experiment with CHO-K1 cells confirmed up-regulation of LXR-beta by the test strains, and treatment with the live L. rhamnosus BFE5264 and L. plantarum NR74 strains significantly increased cholesterol efflux. Heat-killed cells and cell wall fractions of both LAB strains induced the upregulation of ABCG5/8 through LXR activation. By contrast, LAB metabolites did not show any effect on ABCG5/8 and LXR expression. Data from this study suggest that LAB strains, such as L. rhamnosus BFE5264 and L. plantarum NR74, may promote cholesterol efflux in enterocytes, and thus potentially contribute to the prevention of hypercholesterolemia and atherosclerosis.

Cholesterol lowering and inhibition of sterol absorption by Lactobacillus reuteri NCIMB 30242: a randomized controlled trial

“…The possibility, however, that the observed changes in sterol absorption may be a result of Niemann-Pick C1-like 1 transporter inhibition or a combination of cholesterol-reducing mechanisms should be considered. Yoon et al 46 reported that BSH-active Lactobacillus acting on Caco-2 cells resulted in the upregulation of LXR together with elevated expression of ABCG5/G8 transporters and increased cholesterol efflux without noticeable effects on Niemann-Pick C1-like 1 expression. In contrast, a study by Huang and Zheng 47 showed that the probiotic strain L. acidophilus ATCC 4356 reduced Niemann-Pick C1-like 1 gene expression and inhibited the cellular uptake of micellar cholesterol in Caco-2 cells, an effect at least partly mediated by LXR.…”

The Effect of Probiotics on Lipid Metabolism

“…plantarum NR74 also showed a up-regulating the expression of LXR and promotion of cholesterol efflux in Caco-2 cells [78]. This is identical to effect of bile acid sequestrants drug which can also induce an increase of LXR activity in liver [79].…”

Caco-2 Cells for Measuring Intestinal Cholesterol Transport - Possibilities and Limitations

“…Cholesterol uptake and efflux assays were already carried out by different groups, but the described methodology differs in regard to several assay conditions, i.e. differentiation of Caco-2 cells on plates with/without inserts, incubation with cholesterol packaged in micelles or not, composition of the micelles, incubation time and use/no use of acceptors like apoA1 [30][31][32][33][34]. Therefore, we also tested and adjusted these conditions for the cholesterol uptake and efflux assay.…”