Oral malodorous compound inhibits osteoblast proliferation

Area of Science:

• Oral biology
• Cell signaling
• Periodontal disease mechanisms

Background:

• Oral malodorous compounds like hydrogen sulfide (H2S) are linked to periodontitis.
• Volatile sulfur compounds (VSCs) exhibit toxicity to periodontal tissues, impacting collagen, extracellular matrix, and inducing apoptosis.
• H2S toxicity is comparable to cyanate, highlighting its potential role in oral pathology.

Purpose of the Study:

• To investigate the impact of H2S on osteoblast proliferation.
• To elucidate the role of the mitogen-activated protein kinase (MAPK) signaling pathway in H2S-induced effects on osteoblasts.

Main Methods:

• Osteoblasts (human NHOst and murine MC3T3-E1) were exposed to varying concentrations of H2S.
• Cell proliferation was quantified using [3H]thymidine incorporation assays.
• Mitogen-activated protein kinase (MAPK) pathway activation (ERK1/2 and p38 phosphorylation) was assessed via Western blot analysis in NHOst.

Main Results:

• H2S exposure significantly reduced osteoblast proliferation in a dose-dependent manner, with a 79% decrease at 100 ng/ml.
• H2S treatment transiently increased ERK1/2 and p38 phosphorylation, indicating MAPK pathway activation.
• Inhibition of MAPK/ERK kinase (MEK) or p38 blocked H2S-induced activation of these signaling molecules.

Conclusions:

• Hydrogen sulfide (H2S) demonstrably inhibits human osteoblastic cell proliferation.
• The MAPK signaling pathway mediates the inhibitory effects of H2S on osteoblast proliferation.