Increasing the phagocytic activity of microglia could improve the resistance of immunocompromised patients to CNS infections. We studied the microglial responses upon stimulation with the Nod2 ligand muramyl dipeptide (MDP) alone or in combination with a TLR1/2, 3 or 4 agonist. MDP caused a mild release of NO, but induced neither a significant release of pro-inflammatory cytokines nor an expression of molecules associated with professional antigen presentation. Using the Escherichia coli K1 model, microglial pre-stimulation with MDP enhanced bacterial phagocytosis which was strengthened on TLR-pre-stimulated cells. Dual pre-stimulation of Nod2 and TLR1/2 or 4 caused maximal phagocytosis and intracellular killing.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jneuroim.2012.07.012DOI Listing

Publication Analysis

Top Keywords

ligand muramyl
8
muramyl dipeptide
8
phagocytosis intracellular
8
intracellular killing
8
escherichia coli
8
nucleotide-binding oligomerization
4
oligomerization domain-containing-2
4
domain-containing-2 ligand
4
dipeptide enhances
4
enhances phagocytosis
4

Similar Publications

The nucleotide binding oligomerization domain containing 2 (NOD2) protein and its ligand N-acetyl muramyl dipeptide (MDP) are crucially involved in Crohn's disease (CD). However, the mechanism by which NOD2 signaling is regulated in CD patients remains unclear. Ubiquitin specific protease (USP14) is a deubiquitylase that plays an important role in immunity.

View Article and Find Full Text PDF
Article Synopsis
  • Recent studies highlight the role of bacterial peptidoglycan fragments, specifically the muramyl dipeptide (MDP), as signaling molecules from gut bacteria that may influence brain function and behavior.
  • MDP triggers rapid changes in gene expression and cytokine secretion in microglial cells, with its lowest effective dose significantly impacting CCL5, which is crucial for memory and synaptic function.
  • The study suggests that varying MDP levels activate distinct microglial responses by involving NF-κB and MAPK pathways, positioning microglia as key players in the communication between gut microbiota and brain health.
View Article and Find Full Text PDF

Structure-activity relationship in NOD2 agonistic muramyl dipeptides.

Eur J Med Chem

May 2024

Department of Chemistry and Centre of Advanced Studies in Chemistry, Panjab University, Chandigarh, 160014, India; National Interdisciplinary Centre of Vaccine, Immunotherapeutics and Antimicrobials, Panjab University, Chandigarh, 160014, India. Electronic address:

Nucleotide-binding oligomerization domain 2 (NOD2) is a receptor of the innate immune system that is capable of perceiving bacterial and viral infections. Muramyl dipeptide (MDP, N-acetyl muramyl L-alanyl-d-isoglutamine), identified as the minimal immunologically active component of bacterial cell wall peptidoglycan (PGN) is recognized by NOD2. In terms of biological activities, MDP demonstrated vaccine adjuvant activity and stimulated non-specific protection against bacterial, viral, and parasitic infections and cancer.

View Article and Find Full Text PDF

Correction for 'A closer look at ligand specificity for cellular activation of NOD2 with synthetic muramyl dipeptide analogues' by Christopher Adamson , , 2024, , 2212-2215, https://doi.org/10.1039/D3CC05807G.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!