The probiotic Lactobacillus gasseri SBT2055 (LG2055) has anti-obesity effects. Obesity is closely correlated with inflammation in adipose tissue, and maintaining adipose tissue in a less-inflamed state requires intestinal integrity or a barrier function to protect the intestine from the disruption that can be caused by a high-fat diet (HFD). Here, we examined the anti-inflammatory and intestinal barrier-protecting effects of LG2055 in C57BL/6 mice fed a normal-fat diet (NFD), HFD, or the HFD containing LG2055 (HFD-LG) for 21 weeks. HFD-LG intake significantly prevented HFD-induced increases in body weight, visceral fat mass, and the ratio of inflammatory-type macrophages to anti-inflammatory ones in adipose tissue. Mice fed the HFD showed higher intestinal permeability to a fluorescent dextran administered by oral administration and an elevated concentration of antibodies specific to lipopolysaccharides (LPS) in the blood compared with those fed the NFD, suggesting an increased penetration of the gut contents into the systemic circulation. These elevations of intestinal permeability and anti-LPS antibody levels were significantly suppressed in mice fed the HFD-LG. Moreover, treatment with LG2055 cells suppressed an increase in the cytokine-induced permeability of Caco-2 cell monolayers. These results suggest that LG2055 improves the intestinal integrity, reducing the entry of inflammatory substances like LPS from the intestine, which may lead to decreased inflammation in adipose tissue.
Keywords: Anti-inflammation effects; Anti-obesity effects; Diet-induced obesity; FBS, fetal bovine serum; FCM, flow cytometry buffer; FD-4, fluorescein isothiocyanate–dextran; FITC, fluorescein isothiocyanate; HFD, high-fat diet; HFD-LG, high-fat diet containing Lactobacillus gasseri SBT2055; IFN-γ, interferon-γ; Intestinal barrier function; LPS, lipopolysaccharide; LY, Lucifer yellow; Lactobacillus gasseri SBT2055; M1, classically activated macrophages; M2, alternatively activated macrophages; NFD, normal-fat diet; SVF, stromal–vascular fraction; TEER, trans-epithelial electrical resistance.