Ethnopharmacological relevance: Infusions of Solanum chrysotrichum (Schldl.) or "sosa" are employed in Traditional Mexican Medicine for the local and systemic treatment of skin and mucosal infections. Different studies have verified its antifungal effectiveness and therapeutic safety in superficial mycosis caused by dermatophytes or yeasts, and have identified a group of spirostanic saponins, denominated SC-2-SC-6, as responsible for the antifungal activity. Of these, SC-2 is the most active molecule. Electron microscopy studies showed that SC-2 disintegrates cell wall and internal membranes of the fungi studied. In order to continue the systematic study of Solanum chrysotrichum, the goal of the present study was to evaluate the toxicity, genotoxicity, and cytotoxicity of the three different extracts of Solanum chrysotrichum.
Materials and methods: From the dried leaves of Solanum chrysotrichum, we obtained the aqueous, hydroalcoholic, and ethanolic extracts. Saponins (SC-2-SC-6) were quantified by High-performance liquid chromatography (HPLC). For the toxicology study, we formed four groups: three experimental groups, treated with each of the extracts at 1-g/kg doses per os (po) during 4 weeks, and a negative control group treated with the vehicle. For the genotoxicity study, we added another group, which was treated with cyclophosphamide for 1 week. The cytotoxicity study was carried out with international methods and employing the nasopharyngeal cancer (KB) and breast cancer (MDA) cell lines.
Results: The three evaluated extracts did not modify either of the behavioral parameters, and on the hepatic-function biochemical tests (alanine aminotransferase [ALT] and aspartate aminotransferase [AST]), did not showed significant increase on comparing to placebo. The genotoxicity parameters did not exhibit differences between the experimental groups and the placebo (control) group. Histologic analysis showed that the three extracts caused amyloidosis and moderate necrosis in liver, and focal tumefaction in kidney, as well as significant, but clinically irrelevant, elevations of creatinine with the aqueous and hydroalcoholic, but not with the ethanolic, extracts. In addition, the aqueous and ethanolic extracts exhibited interesting cytotoxic activity against the KB cell line.
Conclusions: At the doses administered, the ethanolic extract of Solanum chrysotrichum showed a slightly toxic effect on liver and kidney, without biochemical or genotoxic repercussions and with cytotoxic activity against the KB cell line.
Keywords: Antifungal; Solanaceae; Solanum chrysotrichum; Steroidal saponins; Toxicology and safety.
© 2013 Published by Elsevier Ireland Ltd.