Comparative Oral, Dermal, and Intraperitoneal Acute Toxicity of Gaertnera phanerophlebia (RUBIACEAE) Twig Leaf Extract in Mice

The RUBIACEAE family is a promising source in herbal medicine. Many of them are widely used to treat various diseases in folk medicine. This research aims to promote biodiversity in Madagascar and innovate traditional malagasy medicine. The leafy twigs of Gaertnera phanerophlebia Baker (RUBIACEAE), a species endemic to the Great Island, have been used to treat pain, fever and wounds. Until now, few studies on its pharmacological and toxicological effects have been published thus so far. So, this study aims to verify the safety of the plant extract and determine the possible side effects by comparing its acute toxicity via three different administration routes in mice. In vivo results demonstrated that the leafy twigs crude extract (ST380RF) is non-toxic and non-irritating to the skin according to the Draize index. No mortality or sever effetcs were observed with oral administration up to the maximum dose of 5,000 mg/kg of body weight. Anatomopathological studies of vital organs revealed no adverse effects. However, intraperitoneal injection of the crude extract resulted in the death of some animals, yielding an LD50 of 225,007 mg/kg of b.w, which is considered moderatly toxic according to the Hodge et Sterner classification. Additionally, macroscopic and microscopic analysis of vital organs revealed moderate changes in the spleen and kidneys. These results suggested that the oral and dermal administration of the leafy twigs of this plant appeared harmless and safe for medication. Anyway, since no data are available on the effects of repeated exposure, dermal application seems reasonable for drug development based on the crude extract.