Wound healing activity of Pluchea indica leaf extract in oral mucosal cell line and oral spray formulation containing nanoparticles of the extract

Abstract

Context: Pluchea indica (L.) Less (Asteraceae) is an herb used as a traditional medicine for wound healing. The chemical compounds found in Pluchea indica leaves are phenolic acids, flavonoids, anthocyanins and carotenoids.

Objective: This study investigates the effect of Pluchea indica leaf ethanol extract and its nanoparticles (NPs) on cytotoxicity, cell survival and migration of human oral squamous carcinoma cell line.

Materials and methods: Cell viability was measured using MTT assay to assess the effect of Pluchea indica leaf extract and NPs (1–500 μg/mL) on cytotoxicity and cell survival. The effect of Pluchea indica leaf extract and NPs on cell migration was determined by scratch assay. The % relative migration was calculated after 24, 48 and 72 h of treatment.

Results: The sizes of Pluchea indica leaf extract NPs were in a range of nanometers. NPs possessed negative charge with the polydispersity index (PDI) smaller than 0.3. After the treatment for 24, 48 and 72 h, Pluchea indica leaf extract had IC₅₀ value of 443.2, 350.9 and 580.5 μg/mL, respectively, whereas the IC₅₀ value of NPs after the treatment for 24, 48 and 72 h were 177.4, 149.2 and 185.1 μg/mL, respectively. The % relative migration of cells was significantly increased when the cells were treated with 62.5 and 125 μg/mL of the extract and 62.5 μg/mL of NPs.

Discussion and Conclusions: NPs increased cytotoxicity of the Pluchea indica leaf extract, increased the migration of cells at low concentration and increased colloidal stability of the extract in an oral spray formulation.

Keyword:

• Cytotoxicity
• migration
• cell survival
• HO-1-N-1
• scratch assay
• colloidal stability study
• solvent displacement method

Acknowledgements

The authors gratefully acknowledge the use of the facility of the Research Center for Drug Discovery and Development, Srinakharinwirot University.

Disclosure statement

The authors report no declaration of interest.

Additional information

Funding

This research was supported by Faculty of Pharmacy, Srinakharinwirot University.