Anti-inflammatory effect of Solanum nigrum Linn. ethanolic leaves extract for oral ulcer in LPS stimulated THP 1 cell line

Abstract

Background: Recurrent Aphthous Stomatitis (RAS) is a common inflammatory condition of oral mucosa characterized by recurrent ulcers, significantly affecting the quality of life. The first line of treatment involves corticosteroids, which are associated with a range of adverse effects. Solanum nigrum Linn. (Black nightshade) is a common medicinal herb in India and has demonstrated anti-gastric ulcer effects of S. nigrum L. in previous research. However, to the best of our knowledge, no studies have been conducted to assess the effects of S. nigrum L. on the inflammatory mediators involved in RAS. This study aimed to investigate the anti-inflammatory effects of Solanum nigrum L. on inflammatory mediators of RAS using the THP1 cell line, an in vitro model for studying the pathogenesis of various inflammatory diseases. Materials and methods: Ethanolic extract of S. nigrum L. leaves was done using the Soxhlet apparatus and phytochemical screening for presence of secondary metabolites was performed. THP 1 cells were differentiated into macrophages using phorbol 12- myristate 13- acetate and activated by lipopolysaccharide (LPS). MTT assay was done to measure the cell viability. Results: THP1 cells were pretreated with concentrations (5, 10, 50, 100 µg/mL) of the extract. In vitro evaluation of S. nigrum L. extract at 100µg/mL revealed a statistically significant decrease in inflammatory mediators TNF-α, IL-1ꞵ, and IL-6.                                  Conclusion: This demonstrated that S. nigrum L. extract downregulates the inflammatory responses in RAS. Hence, S. nigrum L. demonstrated significant anti-inflammatory properties and can be used as a potential therapeutic formulation for managing RAS.