Lactobacillus johnsonii L531 Ameliorates Escherichia coli-Induced Cell Damage via Inhibiting NLRP3 Inflammasome Activity and Promoting ATG5/ATG16L1-Mediated Autophagy in Porcine Mammary Epithelial Cells

Abstract

Escherichia coli (E. coli), a main mastitis-causing pathogen in sows, leads to mammary tissue damage. Here, we explored the effects of Lactobacillus johnsonii L531 on attenuating E. coli-induced inflammatory damage in porcine mammary epithelial cells (PMECs). L. johnsonii L531 pretreatment reduced E. coli adhesion to PMECs by competitive exclusion and the production of inhibitory factors and decreased E. coli-induced destruction of cellular morphology and ultrastructure. E. coli induced activation of NLRP3 inflammasome associated with increased expression of NLRP3, ASC, and cleaved caspase-1, however, L. johnsonii L531 inhibited E. coli-induced activation of NLRP3 inflammasome. Up-regulation of interleukin (Il)-1β, Il-6, Il-8, Il-18, tumor necrosis factor alpha, and chemokine Cxcl2 expression after E. coli infection was attenuated by L. johnsonii L531. E. coli infection inhibited autophagy, whereas L. johnsonii L531 reversed the inhibitory effect of E. coli on autophagy by decreasing the expression of autophagic receptor SQSTM1/p62 and increasing the expression of autophagy-related proteins ATG5, ATG16L1, and light chain 3 protein by Western blotting analysis. Our findings suggest that L. johnsonii L531 pretreatment restricts NLRP3 inflammasome activity and induces autophagy through promoting ATG5/ATG16L1-mediated autophagy, thereby protecting against E. coli-induced inflammation and cell damage in PMECs.

Anti-Staphylococcus aureus Single-Chain Fragment Variables Play a Protective Anti-Inflammatory Role In Vitro and In Vivo

“…In the present study, TNF-α, IL-6, and IL-1β exhibited a sharp decrease in scFvs mixture group compared with the NC group (p < 0.05), indicating that scFvs have anti-inflammatory effects on mammary gland tissues. IL-8 and IL-18 contributed to neutrophil chemotaxis, which plays an important role in anti-bacterial immune response [34][35][36]. These studies indicated that suitable levels of five proinflammatory cytokines are vital for host defenses, whereas overmuch production can cause systemic inflammation and damage rather than protective effects.…”

“…IL-8 and IL-18 are the proinflammatory molecules mediated by NFκB signal pathway in an inflammatory microenvironment. Previous studies showed that IL-8 and IL-18 contributed to neutrophil chemotaxis, which plays an important role in antibacterial immune response [34][35][36]. Inhibiting the production of TNF-α, IL-18, IL-6, IL-1β, and IL-8 is helpful to prevent inflammation.…”

The potential of probiotics in the amelioration of hyperuricemia

“…Probiotic intervention is promising for modulating the NLRP3 pathways and has been verified by many studies. 154–157 NLRP3 activation was inhibited by probiotic supplementation, which stabilized osmotic pressure. 158 Lactobacillus also reduced ROS production by restoring the abnormal mitochondrial membrane potential, which alleviated NLRP3 activation.…”

Modulatory Properties of Food and Nutraceutical Components Targeting NLRP3 Inflammasome Activation

“…The beneficial effects of a direct modulation of NLRP3 were also confirmed by a downregulation of pro-inflammatory cytokines, upregulation of anti-inflammatory players. These results have been also described feeding animals or treating cells derived from livestock with probiotics (1 × 10 5 CFU of Lactobacillus rhamnosus GR-1 and 3 × 10 5 –2 × 10 7 CFU of Lactobacillus johnsonii L531) with the aim of limiting the inflammatory damage of bacterial infections induced by Escherichia coli in porcine mammary epithelial cells, MAC-T cells and in a mouse mastitis model, or Salmonella typhimurium in IPEC-J2 cells [ 184 , 185 , 186 ]. The administration of these probiotics allowed limited bacterial adhesion to cells and bacterial alteration of cellular morphology, thus removing the first cause of ROS production and immune system activation.…”