Ethanolic extract of Alternanthera littoralis P. Beauv. aerial parts: Safety assessment and efficacy in experimental models of articular

Abstract

Ethnopharmacological relevance: Alternanthera littoralis P. Beauv. (Amaranthaceae) is an herbaceous species native to Brazil and widely used in traditional medicine. Its aerial parts are commonly prepared as infusions or decoctions and employed to treat inflammatory conditions, microbial infections, and parasitic diseases. Beyond medicinal purposes, it is consumed as a wild edible plant, reflecting its nutritional and cultural significance. Despite these extensive uses, there is limited pharmacological evidence supporting its traditional applications.

Aim of the study: This study aimed to evaluate the anti-inflammatory, analgesic, and anti-arthritic activities of the ethanolic extract obtained from the aerial parts of Alternanthera littoralis (EEAL) and assess its safety profile in toxicological assays in mice.

Materials and methods: EEAL was prepared from authenticated plant material and tested in zymosan-induced arthritis, paw inflammation induced by complete Freund's adjuvant (CFA), and carrageenan-induced pleurisy models. Anti-hyperalgesic, anti-edematous, and anti-inflammatory effects were evaluated alongside biochemical markers. Acute and subacute oral toxicity were assessed according to OECD guidelines.

Results: EEAL significantly reduced joint hyperalgesia, edema, leukocyte migration, myeloperoxidase (MPO) activity, and nitric oxide production across models, with effects comparable to standard anti-inflammatory drugs. The extract was well tolerated in toxicity assays, with no mortality or severe adverse effects. A mild alanine aminotransferase (ALT) elevation was observed at higher doses, without other signs of hepatotoxicity.

Conclusions: EEAL exhibits significant anti-inflammatory, analgesic, and anti-arthritic activities, supporting its traditional use and potential as a safe ethnopharmacological resource. Further studies should focus on compound isolation, chronic toxicity, and pharmacokinetics.

Keywords: Amaranthaceae; Carrageenan; Experimental models; Pleurisy; Safety; Zymosan.