Integrative Wound-Healing Effects of Clinacanthus nutans Extract and Schaftoside Through Anti-Inflammatory, Endothelial-Protective, and Antiviral Mechanisms
Nipitpawn Limpanich, Pattarasuda Chayapakdee, Kullanun Mekawan, Saruda Thongyim, Rujipas Yongsawas, Phanuwit Khamwong, Yingmanee Tragoolpua, Thida Kaewkod, Siriphorn Jangsutthivorawat, Jarunee Jungklang, Usawadee Chanasut, Angkhana Inta, Phatchawan Arjinajarn, Aussara Panya, Hataichanok Pandith
Abstract
Clinacanthus nutans (Burm.f.) Lindau is a Southeast Asian medicinal plant traditionally used for treating skin inflammation and infections. This study evaluated its wound-healing potential through anti-inflammatory, cytoprotective, and antiviral mechanisms. HPLC-DAD analysis identified schaftoside as the major flavonoid in the 95% ethanolic leaf extract. In the lipopolysaccharide (LPS)-stimulated murine macrophage cell line (RAW 264.7), both C. nutans extract (5 and 50 μg/mL) and its flavonoid schaftoside (5 and 20 μg/mL) significantly downregulated the expression of pro-inflammatory genes, including cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and prostaglandin E2 (PGE2), under both pre-treatment and post-treatment conditions. ELISA confirmed dose-dependent inhibition of human COX-2 enzymatic activity, reaching up to 99.3% with the extract and 86.9% with schaftoside. In the endothelial cell models (CCL-209), the extract exhibited low cytotoxicity and effectively protected cells from LPS-induced apoptosis, preserving vascular integrity critical to tissue regeneration. Antiviral assays demonstrated suppression of HSV-2 replication, particularly during early infection, which may help prevent infection-related delays in wound healing. Collectively, these findings suggest that C. nutans and schaftoside promote wound repair by attenuating inflammatory responses, supporting endothelial survival, and controlling viral reactivation. These multifunctional properties highlight their potential as natural therapeutic agents for enhancing wound-healing outcomes.