In this study, the effect of Lactobacillus plantarum lipoteichoic acid (pLTA) on LPS-induced MAPK activation, NF-κB activation, and the expression of TNF-α and IL-1R-associated kinase M (IRAK-M) was examined. The expression of the pattern recognition receptor and the survival rate of mice were also examined. pLTA pretreatment inhibited the phosphorylation of ERK, JNK, and p38 kinase. It also inhibited the degradation of IκBα and IκBβ, as well as the activation of the LPS-induced TNF-α factor in response to subsequent LPS stimulation. These changes were accompanied by the suppression of the LPS-induced expression of TLR4, NOD1, and NOD2, and the induction of IRAK-M, with a concurrent reduction of TNF-α secretion. Furthermore, the overexpression of pattern recognition receptors such as TLR4, NOD1, and NOD2 and the degradation of IRAK-M by transient transfection were found to reinstate the production of TNF-α after LPS restimulation. In addition, the i.p. injection of pLTA suppressed fatality, and decreased the level of TNF-α in the blood, in LPS-induced endotoxin shock mice. In conclusion, these data extend our understanding of the pLTA tolerance mechanism, which is related to the inhibition of LPS-induced endotoxin shock, and suggest that pLTA may have promise as a new therapeutic agent for LPS-induced septic shock.
In this study, the stimulatory effects of different lactic acid bacteria strains, and their subcellular fractions, on the THP-1 cell line were evaluated. Lactobacillus plantarum was found in particular to induce high levels of IL-23p19 mRNA, but it moderately induced TNF-a production. IL-10 production was not entirely affected by L. plantarum stimulation. When subcellular fractions of L. plantarum were used to treat THP-1 cells, IL-23p19 mRNA expression was enhanced in a doseresponsive manner, specifically by lipoteichoic acid (LTA). The cotreatment of THP-1 cells by both L. plantarum and Staphylococcus aureus LTA resulted in decreased IL-10 production when compared with cells treated by S. aureus LTA alone. Taken together, these data suggest that LTA isolated from L. plantarum elicits stimulatory effects upon the expression of IL-23p19 and inhibitory effects on pathogen-mediated IL-10 production.
It is known that lactic acid bacteria (LAB) have many beneficial health effects, including antioxidative activity and immune regulation. In this study, the immune regulatory effects of Lactobacillus sakei and Lactobacillus plantarum, which are found in different types of kimchi, were evaluated. L. sakei and its lipoteichoic acid (LTA) have greater immune stimulating potential in IL-12, IFN-γ, and TNF-α production as compared with L. plantarum in an in vitro condition. On the other hand, L. plantarum is assumed to repress the Th1 immune response in murine experiments. After being injected with LPS, L. plantarum-fed mice maintained a healthier state, and the level of TNF-α in their blood was lower than in other bacterial strainfed mice and in the LPS-only control mice. Additionally, IL-12 production was significantly decreased and the production of IL-4 was greatly increased in the splenocytes from L. plantarum-fed mice. Further experiments revealed that the pre-injection of purified LTA from L. plantarum (pLTA), L. sakei (sLTA), and S. aureus (aLTA) decreased TNF-α and IL-4 production in LPS-injected mice. Mouse IL-12, however, was significantly increased by aLTA pre-injection. In conclusion, the L. sakei and L. plantarum strains have immune regulation effects, but the effects differ in cytokine production and the regulatory effects of the Th1/Th2 immune response.
The lipoteichoic acid (LTA) of Staphylococcus aureus (aLTA) and Lactobacillus plantarum (pLTA) engage the same toll-like receptor 2 (TLR2) signaling pathway but exert different effects on innate immunity and inflammation. The mechanisms underlying these differential effects are not yet clear. Human oligonucleotide microarrays were used to investigate the transcriptome of human THP-1 monocytes upon exposure to aLTA or pLTA, and differential gene expression profiles were observed between the aLTA-and pLTA-treated cells. The expression level of 1,302 genes in aLTAtreated cells increased more than 2-fold; some of which have been implicated in immune or inflammatory responses, cell adhesion, cell signal transduction, transcription factors, anion transport, proteolysis, and oxidative processes. Particularly, a variety of genes that encode cytokines and chemokines, and TLR signaling-related molecules belonging to the tumor necrosis factor receptor-associated factor (TRAF), nuclear factor-kappa B, and signal transducer and activator of transcription families were remarkably up-regulated by aLTA stimulation. In contrast, pLTA treatment altered the expression of only 90 genes by more than 1.5-fold, and these genes were not correlated with innate immunity, inflammation or other related processes. The different effects mediated by aLTA and pLTA were further verified and compared by analysis of the expression of a selected group of genes, including TRAFs and some cytokines and chemokines, using real time-polymerase chain reaction and ELISA. These data suggest that aLTA and pLTA have different immunomodulatory potentials. Compared with pLTA, aLTA is a stronger stimulator and impacts the expression of many innate immunity-and/or inflammation-related genes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.