title: Bacterial cell wall components regulate adipokine secretion from visceral adipocytes.
abstract: Recent studies suggest a relationship between intestinal microbiota and metabolic syndromes; however, the underlying mechanism remains unclear. To clarify this issue, we assessed the effects of bacterial cell wall components on adiponectin, leptin and resistin secretion from rat visceral adipocytes in vitro. We also measured the relative population of Firmicutes and Bacteroidetes in fecal microbiota and the amount of fecal mucin as an intestinal barrier function, when mice were fed a high-fat diet. In the present study, we demonstrated that bacterial cell wall components affect the secretion of adipokines, depending on the presence of antigens from gram-positive or gram-negative bacteria. Lipopolysaccharide markedly inhibited adiponectin, leptin, and resistin secretion, whereas peptidoglycan increased adiponectin secretion and decreased resistin secretion in vitro. In vivo experiments showed that the high-fat diet increased the population of Firmicutes and decreased that of Bacteroidetes. In contrast, the high-fat diet downregulated the stool output and fecal mucin content. These results demonstrate that bacterial cell wall components affect the onset of metabolic syndromes by mediating the secretion of adipokines from visceral adipose tissue. Furthermore, we believe that metabolic endotoxemia is not due to the increasing dominance of gram-negative bacteria, Bacteroidetes, but due to the depression of intestinal barrier function.
authors.affiliation: Division of Biology, Department of Biological Sciences, School of Science, Hokkaido University, Kita10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan.
authors.forename: Risa
authors.initials: R
authors.lastname: Taira
authors.affiliation: Cosmo Bio Co., Ltd., Primary Cell Division, YS Bldg, 1-12 12 Nishimachi-kita, Sapporo 063-0061, Japan.
authors.forename: Sayori
authors.initials: S
authors.lastname: Yamaguchi
authors.affiliation: Cosmo Bio Co., Ltd., Primary Cell Division, YS Bldg, 1-12 12 Nishimachi-kita, Sapporo 063-0061, Japan.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Shimizu
authors.affiliation: Department of Cell Biological Science, Faculty of Advanced Life Science, Graduate School of Life Science, Hokkaido University, North 21 West 11, Kita-ku, Sapporo 001-0021, Japan.
authors.forename: Kiminori
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: Department of Cell Biological Science, Faculty of Advanced Life Science, Graduate School of Life Science, Hokkaido University, North 21 West 11, Kita-ku, Sapporo 001-0021, Japan.
authors.forename: Tokiyoshi
authors.initials: T
authors.lastname: Ayabe
authors.affiliation: Cosmo Bio Co., Ltd., Primary Cell Division, YS Bldg, 1-12 12 Nishimachi-kita, Sapporo 063-0061, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Taira
keywords: adipokine secretion; gut microbiota; lipopolysaccharide; peptidoglycan; visceral adipocyte