Lpp of Escherichia coli K1 inhibits host ROS production to counteract neutrophil-mediated elimination

Zhang, Xuewei; An, Ming-Xin; Huang, Zeng-Kang; Ma, Lan; Zhao, Dan; Zhao, Yang; Shi, Junxiu; Liu, Dongxin; Li, Qiang; Wu, Anhua; Chen, Yuhua; Zhao, Wei‐Dong

doi:10.1016/j.redox.2022.102588

Cited by 6 publications

(3 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The cells were incubated with subinhibitory concentrations (1/8, 1/4, or 1/2 of the MIC) of glabridin, infected with L. monocytogenes at an MOI of 10:1, and then incubated at 37°C with 5% CO 2 for 2 h. The cells were stained with Hoechst 33342 (Beyotime Biotechnology, Shanghai, China) and observed via confocal laser scanning microscopy (FV3000, Olympus, Japan) at 350 nm excitation and 460 nm emission. Images of random fields were acquired from each group ( Zhang X. W. et al, 2023 ). The MET formation in the PMA-treated macrophages was set as 100%.…”

Section: Methodsmentioning

confidence: 99%

Subinhibitory concentrations of glabridin from Glycyrrhiza glabra L. reduce Listeria monocytogenes motility and hemolytic activity but do not exhibit antimicrobial activity

Liao,

Yu,

Guo

et al. 2024

Front. Microbiol.

View full text Add to dashboard Cite

Increases in the virulence and survival of some pathogens in the presence of subinhibitory concentrations of antibiotics have been reported. However, research on the effects of subinhibitory concentrations of antimicrobial substances derived from traditional Chinese medicine on pathogens is still insufficient. Glabridin is a well-known active isoflavone found in licorice roots that possesses a wide range of biological activities. Therefore, in this study, Listeria monocytogenes (L. monocytogenes) exposed to subinhibitory concentrations of glabridin was used as the research object. The minimum inhibitory concentration (MIC) was determined for L. monocytogenes. We investigated the impacts of subinhibitory concentrations of glabridin on the morphology, motility, biofilm formation, adherence, and survival of L. monocytogenes. The results indicated that the MIC of glabridin for L. monocytogenes was 31.25 μg/mL. At 1/8, 1/4, or 1/2 of the MIC, glabridin did not affect the growth, morphology, flagellar production, or biofilm formation of L. monocytogenes. However, subinhibitory concentrations of glabridin inhibited bacterial swimming and swarming motility and decreased the hemolytic activity of L. monocytogenes. Glabridin reduced the hemolytic activity of L. monocytogenes culture supernatants. The results also showed that subinhibitory concentrations of glabridin had no toxic effect on RAW264.7 cells but decreased the intracellular growth of L. monocytogenes in RAW264.7 cells. Furthermore, subinhibitory concentrations of glabridin triggered ROS production but did not induce MET formation in macrophages. In addition, glabridin did not enhance the capacity of L. monocytogenes to trigger METs or the extracellular killing of macrophages by METs. Thus, we conclude that subinhibitory concentrations of glabridin reduce L. monocytogenes motility and hemolytic activity but do not exhibit antimicrobial activity. Glabridin could be an interesting food additive as a bacteriostatic agent with anti-Listeria activity.

show abstract

Section: Methodsmentioning

confidence: 99%

Subinhibitory concentrations of glabridin from Glycyrrhiza glabra L. reduce Listeria monocytogenes motility and hemolytic activity but do not exhibit antimicrobial activity

Liao,

Yu,

Guo

et al. 2024

Front. Microbiol.

View full text Add to dashboard Cite

show abstract

“…A subsequent increase in T cells in the lungs suggests that neonatal neutrophils can also efficiently recruit T cells. These responses, however, were not observed in P5 pups inoculated with wildtype B. pertussis , suggesting that pertussis toxin disrupts neutrophil accumulation in the lungs [ 29 ]. Similarly, a mutant of E. coli lacking Lpp was successfully controlled in mice and rats by P5–P9.…”

Section: The Neonatal Immune System Is Composed Of Unique Cellsmentioning

confidence: 99%

“…This control required NADPH oxidase-generated ROS from neutrophils. However, this effect was not observed in wildtype E. coli , suggesting that Lpp suppresses neutrophil killing to promote disease in neonates [ 29 ]. This suggests that pathogens produce specific factors which disrupt neonatal neutrophils and prevent control of infection from neonatal lungs.…”

Section: The Neonatal Immune System Is Composed Of Unique Cellsmentioning

confidence: 99%

The Neonatal Immune System and Respiratory Pathogens

Sedney

Harvill

2023

Microorganisms

View full text Add to dashboard Cite

Neonates are more susceptible to some pathogens, particularly those that cause infection in the respiratory tract. This is often attributed to an incompletely developed immune system, but recent work demonstrates effective neonatal immune responses to some infection. The emerging view is that neonates have a distinctly different immune response that is well-adapted to deal with unique immunological challenges of the transition from a relatively sterile uterus to a microbe-rich world, tending to suppress potentially dangerous inflammatory responses. Problematically, few animal models allow a mechanistic examination of the roles and effects of various immune functions in this critical transition period. This limits our understanding of neonatal immunity, and therefore our ability to rationally design and develop vaccines and therapeutics to best protect newborns. This review summarizes what is known of the neonatal immune system, focusing on protection against respiratory pathogens and describes challenges of various animal models. Highlighting recent advances in the mouse model, we identify knowledge gaps to be addressed.

show abstract

Pathogens in engineered water systems

Huang,

Zhao,

et al. 2024

Water Security: Big Data-Driven Risk Identification, Assessment and Control of Emerging Contaminants

View full text Add to dashboard Cite

Lpp of Escherichia coli K1 inhibits host ROS production to counteract neutrophil-mediated elimination

Cited by 6 publications

References 49 publications

Subinhibitory concentrations of glabridin from Glycyrrhiza glabra L. reduce Listeria monocytogenes motility and hemolytic activity but do not exhibit antimicrobial activity

Subinhibitory concentrations of glabridin from Glycyrrhiza glabra L. reduce Listeria monocytogenes motility and hemolytic activity but do not exhibit antimicrobial activity

The Neonatal Immune System and Respiratory Pathogens

Pathogens in engineered water systems

Contact Info

Product

Resources

About