A single application of hydrogen sulphide induces a transient osteoclast differentiation with RANKL expression in the rat model

Accepted 14 May 2009.

Abstract

Objective

Oral malodor is mainly attributed to volatile sulphur compounds (VSCs) such as hydrogen sulphide (H2S), methyl mercaptan and dimethyl sulphide. VSC accelerate periodontal soft tissue destruction. However, there is little information about the potential role of H2S in alveolar bone loss. The purpose of this animal study was to examine the effects of sodium hydrogen sulphide (NaHS), H2S donor drug, on osteoclast differentiation in rat periodontal tissue.

Design

Twenty-four male Wistar rats (8 weeks old) were divided into four groups: a control group and three experimental groups, which were examined at 3h, 1 day, and 3 days after topical application of 3μl NaHS (lM in physiological saline) into the gingival sulcus of rat first molar. Expression of tumour necrosis factor (TNF)-α, RANKL, NF-κB and tartrate-resistant acid phosphatase (TRAP) was evaluated in the periodontal tissue.

Results

Three hours after NaHS application, TNF-α expression increased in the periodontal ligament. The numbers of RANKL-positive osteoblasts and TRAP-positive osteoclasts significantly increased progressively with time and reached a maximum level after 1 day. Significant up-regulation of RANKL and NF-κB mRNA was observed at 3h after NaHS application.

Conclusions

H2S application caused a transient increase of osteoclast differentiation with up-regulation of RANKL expression in osteoblasts. H2S, which is primarily responsible for halitosis, may also contribute to alveolar bone resorption through RANKL expression.

Abbreviations: VSC, volatile sulphur compounds, H2S, hydrogen sulphide, NaHS, sodium hydrogen sulphide, NF, nuclear factor, RANKL, receptor activator of nuclear factor-κB ligand, TRAP, tartrate-resistant acid phosphatase, TNF-α, tumour necrosis factor-α, IL, interleukin, RT-PCR, reverse transcription-polymerase chain reaction

Keywords: Hydrogen sulphide, Osteoclast, RANKL, Periodontal disease

a Department of Preventive Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8525, Japan

b Department of Dental Sociology, Division of Sociological Approach in Dentistry, Kanagawa Dental College, 82 Inaoka-cho, Yokosuka 238-8580, Japan

c Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, Canada

d Department of Oral Health, School of Life Dentistry, Nippon Dental University, Japan

Corresponding author. Tel.: +81 86 235 6712; fax: +81 86 235 6714.

PII: S0003-9969(09)00126-5

doi:10.1016/j.archoralbio.2009.05.006

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