Toxicological assessment of the Achyrocline satureioides aqueous extract in the Caenorhabditis elegans alternative model

ABSTRACT

Achyrocline satureioides, popularly called “marcela” in Brazil, is used in traditional medicine in South America. A. satureioides, inflorescences are used for many conditions, including to minimize the Sars-Cov-2 symptoms. Therefore, the aim of this study was to determine the toxicity profile of A. satureioides aqueous extract (ASAE), using the Caenorhabditis elegans (C. elegans) alternative model. Survival, reproduction, development, and transgenerational assays were performed. The effects of ASAE were investigated under conditions of thermal stress and presence of oxidant hydrogen peroxide (H₂O₂). In addition, C. elegans strains containing high antioxidant enzyme levels and elevated lineages of daf-16, skn-1 and daf-2 regulatory pathways were examined. The ASAE LC₅₀ value was found to be 77.3 ± 4 mg/ml. The concentration of ASAE 10 mg/ml (frequently used in humans) did not exhibit a significant reduction in worm survival at either the L1 or L4 stage, after 24 or 72 hr treatment. ASAE did not markedly alter the body area. In N2 strain, ASAE (10 or 25 mg/ml) reversed the damage initiated by H₂O₂. In addition, ASAE protected the damage produced by H₂O₂ in strains containing significant levels of sod-3, gst-4 and ctl − 1,2,3, suggesting modulation in these antioxidant systems by this plant extract. ASAE exposure activated daf-16 and skn-1 stress response transcriptional pathways independently of daf-2, even under extreme stress. Data suggest that ASAE, at the concentrations tested in C. elegans, exhibits a reliable toxicity profile, which may contribute to consideration for safe use in humans.

GRAPHICAL ABSTRACT

KEYWORDS:

• Achyrocline satureioides
• Caenorhabditis elegans
• marcela
• oxidative stress
• toxicity
• gene expression
• nuclear translocation

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding author, upon reasonable request.

Additional information

Funding

This work was supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) (number 88887.506777/2020–00); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) fellowships (Dr. Patrícia Pereira; number 304870/2022-6).