Anti-Inflammatory, Antioxidant, and Reparative Effects of Casearia sylvestris Leaf Derivatives on Periodontium In Vitro

Abstract

Gingival inflammation compromises the integrity of the gingival epithelium and the underlying tissues, highlighting the need for adjuvant therapies with immunomodulatory and healing properties. <i>Casearia sylvestris</i>, a medicinal plant known as guaçatonga, is traditionally used to treat inflammatory lesions. This study aimed to investigate the effects of <i>C. sylvestris</i> on the synthesis of pro- and anti-inflammatory, proteolytic, and antioxidant molecules and on wound healing in epithelial cells. A human telomerase-immortalized gingival keratinocyte cell line (TIGKs) was used, and cells were exposed to <i>Escherichia coli</i> lipopolysaccharide (LPS) in the presence and absence of <i>C. sylvestris</i> extract, its diterpene-concentrated fraction, and its clerodane diterpene casearin J for 24 h and 48 h. Gene expression and protein synthesis were analyzed by RT-qPCR and ELISA, respectively. Nitric oxide (NO) and NF-κB activation were analyzed by Griess reaction and immunofluorescence, respectively. Additionally, cell viability was evaluated by alamarBlue^® assay, and an automated scratch assay was used for wound healing. LPS significantly increased the expression of cytokines (TNF-α, IL-1β, IL-6, IL-8, IL-10, IL-17), proteases (MMP-1 and MMP-13), iNOS as well as NO synthesis, and triggered NF-κB nuclear translocation. It also reduced IL-4 expression, cell viability, and cellular wound repopulation. Treatment with <i>C. sylvestris</i> derivatives significantly abrogated all aforementioned LPS-induced effects by 80-100%. Furthermore, even at higher concentrations, <i>C. sylvestris</i> did not affect cell viability, thus proving the safety of its derivatives. <i>C. sylvestris</i> exerts anti-inflammatory, antiproteolytic, and antioxidant effects on gingival keratinocytes, highlighting its potential as a valuable adjunct in the prevention and treatment of periodontal diseases.