An in vitro anti-inflammatory effect of Thai propolis in human dental pulp cells.

Abstract

OBJECTIVE:

To explore the potential for development of Thai propolis extract as a pulp capping agent to suppress pulpal inflammation from dental pulp infections. This study aimed to examine the anti-inflammatory effect of the propolis extract on the arachidonic acid pathway, activated by interleukin (IL)-1β, in cultured human dental pulp cells.

METHODOLOGY:

Dental pulp cells, isolated from three freshly extracted third molars, were first characterized for their mesenchymal origin and treated with 10 ng/ml of IL-1β in the presence or absence of non-toxic concentrations of the extract from 0.08 to 1.25 mg/ml, as determined by the PrestoBlue cytotoxic assay. Total RNA was harvested and analyzed for mRNA expressions of 5-lipoxygenase (5-LOX) and cyclooxygenase-2 (COX-2). Western blot hybridization was performed to investigate COX-2 protein expression. Culture supernatants were assayed for released prostaglandin E2 levels. Immunofluorescence was conducted to determine involvement of nuclear factor-kappaB (NF-kB) in the inhibitory effect of the extract.

RESULTS:

Stimulation of the pulp cells with IL-1β resulted in the activation of arachidonic acid metabolism via COX-2, but not 5-LOX. Incubation with various non-toxic concentrations of the propolis extract significantly inhibited upregulated COX-2 mRNA and protein expressions upon treatment with IL-1β (p<0.05), resulting in a significant decrease in elevated PGE2 levels (p<0.05). Nuclear translocation of the p50 and the p65 subunits of NF-kB upon treatment with IL-1β was also blocked by incubation with the extract.

CONCLUSIONS:

Upregulated COX-2 expression and enhanced PGE2 synthesis upon treatment with IL-1β in human dental pulp cells were suppressed by incubation with non-toxic doses of Thai propolis extract via involvement of the NF-kB activation. This extract could be therapeutically used as a pulp capping material due to its anti-inflammatory properties.

• Authors: Nutthapong Kantrong, Jittranut Kumtawee, Teerasak Damrongrungruang, Subin Puasiri, Anupong Makeudom, Suttichai Krisanaprakornkit, Pattama Chailertvanitkul
• Journal: Journal of applied oral science : revista FOB (J Appl Oral Sci) Vol. 31 Pg. e20230006 ( 2023) ISSN: 1678-7765 [Electronic] Brazil
• PMID: 37283330 (Publication Type: Journal Article)

Chemical References

• Anti-Inflammatory Agents
• Arachidonic Acid
• Cyclooxygenase 2
• Dinoprostone
• NF-kappa B
• Plant Extracts
• Propolis
• RNA, Messenger

Topics

• Humans
• Anti-Inflammatory Agents (pharmacology)
• Arachidonic Acid (pharmacology)
• Cells, Cultured
• Cyclooxygenase 2 (metabolism)
• Dental Pulp (cytology, drug effects)
• Dinoprostone (metabolism)
• NF-kappa B
• Plant Extracts
• Propolis (pharmacology)
• RNA, Messenger (metabolism)