Related Experiment Video
Updated: Jun 23, 2026
07:15
Robust Ligature-Induced Model of Murine Periodontitis for the Evaluation of Oral Neutrophils
Published on: January 21, 2020
TGF-beta1 Inhibits TLR-mediated odontoblast responses to oral bacteria
O V Horst1, K A Tompkins, S R Coats
1Department of Oral Biology, University of Washington, Seattle, WA 98195-7132, USA.
Journal of Dental Research
|May 2, 2009
Summary
Transforming growth factor-beta1 (TGF-beta1) impacts odontoblast responses to oral bacteria by modulating Toll-like receptor (TLR) expression. This balance influences pulpal inflammation during dental caries.
Area of Science:
- Oral biology
- Immunology
- Dental research
Background:
- Transforming growth factor-beta1 (TGF-beta1) has known roles in tooth development and repair.
- Its specific function in the tooth's microbial defense system, particularly concerning odontoblast responses to oral bacteria, remains unclear.
- Odontoblasts are crucial in sensing bacterial signals within carious dentin.
Purpose of the Study:
- To investigate the role of TGF-beta1 in modulating odontoblast responses to various oral bacteria.
- To determine the involvement of Toll-like receptors (TLRs) in these bacterial recognition pathways.
Main Methods:
- Assessing odontoblast responses to specific oral bacteria (Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, Streptococcus mutans, Enterococcus faecalis, Lactobacillus casei).
- Analyzing the expression levels of Toll-like receptors (TLR2 and TLR4) on odontoblast cell surfaces.
- Evaluating the impact of TGF-beta1 on TLR expression and subsequent odontoblast activation.
Main Results:
- Odontoblast responses to bacteria were dependent on TLR2 and TLR4 expression.
- Certain bacteria (P. gingivalis, P. intermedia, F. nucleatum) activated both TLRs, with TLR4 being more significant.
- A deficiency in cell-surface TLR2 correlated with diminished responses to other bacteria (S. mutans, E. faecalis, L. casei).
- TGF-beta1 was found to inhibit TLR2 and TLR4 expression, thereby reducing odontoblast reactivity.
Conclusions:
- The interplay between TLR-mediated inflammation and TGF-beta1's anti-inflammatory effects is critical in regulating pulpal inflammation.
- Understanding this balance is key to developing strategies for managing dental caries and associated inflammatory conditions.
Related Concept Videos
01:27The Oral Microbiota
The oral microbiome includes a complex ecosystem comprising over 700 microbial species, identified through genomic sequencing and culture-based analyses to date. This community includes a core microbiome, found universally among individuals, and a variable component influenced by environmental factors such as diet, lifestyle, and host genetics. Site-specific conditions, including oxygen gradients, pH levels, and nutrient availability, determine the spatial distribution of these microorganisms...
01:16TGF - β Signaling Pathway
The TGF-β signaling pathway regulates cell growth, differentiation, adhesion, motility, and development. TGF-β ligands that induce TGF-β signaling are synthesized in their latent form. Several proteases or cell surface receptors such as integrins act upon the latent form, releasing the active ligand. There are three types of mammalian TGF-βs: (TGF-β1, TGF-β2, and TGF-β3) that bind as homodimers or heterodimers to TGF-β receptors. The TGF-β receptors are of three kinds RI, RII, and RIII. The RI...
01:22Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...
01:17Hormones and Bone Tissue
The endocrine system produces and secretes hormones, which interact with the skeletal system. These hormones control bone growth, maintain bone once it is formed, and remodel it.
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
02:26NF-κB-dependent Signaling Pathway
The transcription factor NF-κB was discovered in 1986 in the lab of Nobel laureate Professor David Baltimore, for its interaction with the immunoglobulin light chain enhancer in B-cells. After more than three decades of study, it is now evident that NF-κB regulates the expression of over 100 genes. Most of these genes play an essential role in the innate and adaptive immune responses as well as the inflammatory responses of animals.
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
01:28Development of the Oral Microbiota
The establishment of the oral microbiome begins before birth, challenging the long-held belief that the fetal oral cavity is sterile. The presence of oral microbes such as Streptococcus and Fusobacterium in amniotic fluid suggests that microbial exposure may occur in utero, potentially through translocation from the maternal oral or gastrointestinal tract. This early colonization primes the neonatal immune system and sets the stage for subsequent microbial succession. Maternal health,...