Antioxidative and anti-cytogenotoxic potential of Lysiphyllum strychnifolium (Craib) A. Schmitz extracts against cadmium-induced toxicity in human embryonic kidney (HEK293) and dermal fibroblast (HDF) cells.

Exposure to cadmium (Cd) results in bioaccumulation and irreversible damage; this encourages an investigation of alternatives to address Cd toxicity, using natural compounds. Lysiphyllum strychnifolium , a well-known Thai medicinal plant, was investigated for its phytochemical compounds and corresponding bioactivities, including antioxidant and anti-cytogenotoxic effects against Cd toxicity in HEK293 renal and HDF dermal cell models. The crude extract of L. strychnifolium (LsCrude) was partitioned into four fractions, using sequential polarity solvents (hexane, dichloromethane, ethyl acetate, and water, denoted as LsH, LsD, LsE, and LsW, respectively). The extraction yields were 1.79 %, 5.08 %, 8.53 %, and 70.25 % (w/w), respectively. Phytochemical screening revealed the presence of tannins, alkaloids, and flavonoids in LsCrude and its fractions, except for LsH. LsE exhibited the highest concentrations of phenolics (286.83 ± 6.83 mg GAE/g extract) and flavonoids (86.36 ± 1.29 mg QE/g extract). Subsequent 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging and ferric-reducing ability of plasma (FRAP) reducing powder assays demonstrated the high antioxidant capacity of LsCrude and its fractions. The lowest IC ₅₀ value (9.11 ± 0.43 μg/mL) in the DPPH assay corresponded to LsW, whereas the highest total FRAP value (6.06 ± 0.70 mg QE Eq./g dry mass) corresponded to LsE. MTT and alkaline comet assays revealed the lack of toxicity of the extracts, which were considered safe. Upon exposure to Cd at the CC ₅₀ level, HEK293 cells treated with LsE suppressed Cd-induced damage. HDF cells treated with LsCrude, LsD, or LsE attenuated Cd-induced damage. In the pre-treatment, LsD protected the HDF cells against Cd-mediated cytogenotoxicity. These anti-cytogenotoxic potentials are likely due to the antioxidant properties of the phytochemicals. Our findings highlight the cyto-geno-protective properties of L. strychnifolium stem extracts against Cd toxicity in HEK293 and HDF cells, and provide a novel approach for combating oxidative stress and DNA damage caused by environmental pollutants.
Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors gratefully acknowledge the financial support from the Faculty of Pharmaceutical Sciences, Prince of Songkla University, and National Science, Research and Innovation Fund (NSRF) and Prince of Songkla University (Grant No PHA6601315S). The authors also would like to thank the Faculty of Pharmaceutical Sciences, and Phytomedicine and the Pharmaceutical Biotechnology Excellence Center (PPBEC) for providing laboratory facilities. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(© 2024 The Authors. Published by Elsevier Ltd.)