Toxicological evaluation by in vitro and in vivo assays of an aqueous extract prepared from Echinodorus macrophyllus leaves

• Published in: Toxicology letters Vol. 116; no. 3; pp. 189 - 198
• Main Authors: da Costa Lopes, Leonardo, Albano, Franco, Augusto Travassos Laranja, Gustavo, Marques Alves, Luciano, Fernando Martins e Silva, Luis, Poubel de Souza, Gabriele, de Magalhães Araujo, Isabela, Firmino Nogueira-Neto, José, Felzenszwalb, Israel, Kovary, Karla
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 16.08.2000; Amsterdam Elsevier Science
• Subjects: Animals; Aqueous extract; Biological and medical sciences; Body Weight - drug effects; Cell Survival - drug effects; Comet assay; DNA - drug effects; Dose-Response Relationship, Drug; Drug toxicity and drugs side effects treatment; Echinodorus macrophyllus; Genotoxicity; Humans; Male; Medical sciences; Mice; Miscellaneous (drug allergy, mutagens, teratogens...); Mutagenicity; Mutagenicity Tests; Organ Size - drug effects; Pharmacology. Drug treatments; Plant Extracts - toxicity; Plants, Medicinal; Rats; Tumor Cells, Cultured; South America; Brazil; America; ALT, alanine aminotransferase; DMEM, Dulbecco's Minimal Essential Medium; EDTA, ethylenediaminetetraacetic acid; Genotoxicity; FBS, fetal bovine serum; Aqueous extract; ALP, alkaline phosphatase; Comet assay; DMSO, dimethylsulfoxide; PBS, phosphate-buffered saline; NaOH, sodium hydroxide; Tris, Tris(hydroxymethyl)aminomethane; BPB, bromophenol blue; TCA, trichloroacetic acid; Mutagenicity; Echinodorus macrophyllus; AST, aspartate aminotransferase; Monocotyledones; Pharmacognosy; Mutagenicity testing; Toxicity; Rodentia; Plant leaf; Medicinal plant; Vertebrata; Mammalia; Folk medicine; Mouse; Animal; DNA; Angiospermae; Spermatophyta; Alismataceae; Aqueous solution
• ISSN: 0378-4274; 1879-3169
• DOI: 10.1016/S0378-4274(00)00220-4

Toxicity of an aqueous extract prepared from Echinodorus macrophyllus dried leaves, a plant used in folk medicine to treat inflammation and kidney malfunctions, was estimated by different bioassays. Mutagenicity of the aqueous extract was evaluated in the Salmonella/microsome assay (TA97a, TA98, TA100 and TA102 strains), with or without metabolic activation. No mutagenic activity (lyophilized extract tested up to 50 mg/plate) could be detected to any of the tester strain. Furthermore, no cytotoxic effect has been observed when a crude extract of E. macrophyllus (up to 7.5 mg/ml) was tested on the exponential growth of hepatoma and normal kidney epithelial cells in culture. Toxicity of E. macrophyllus was also evaluated in male Swiss mice after 6 weeks of continuous ingestion of the aqueous extract in drinking water. Average daily ingested doses were 3, 23 and 297 mg/kg for a lyophilized extract, and 2200 mg/kg for a crude extract, with dose two being equivalent to the daily dose recommended to humans. At the end of the treatment, all animals revealed a deficit in final body weight ranging from 5 to 47%. Biochemical analysis of the plasma revealed some minor alterations indicating subclinical hepatic toxicity. Genotoxic effect on liver, kidney and blood cells has been also evaluated by the comet assay, being negative to liver and blood cells. However, DNA analyses of the kidney cells detected some genotoxic activity for the highest dose tested of E. macrophyllus extract, either lyophilized or crude. On the other hand, exposure dose of 23 mg/kg, equivalent to the daily dose recommended to humans, did not revealed any genotoxic effect and hence this herb seems to be safe to human organism.