Toxicity analysis of the methanolic extract of Gaertnera phanerophlebia Baker (RUBIACEAE): Aerial parts

Recently, herbal medicines have become increasingly popular, with high usage rates in Africa (90 %) and in India (70 %). In Madagascar, they are considered a good, natural alternative to allopathic medicines. However, as more and more herbal drugs are recommended, concerns about their safety have emerged. Consumers and some practitioners have limited knowledge of the potential risks of herbal remedies. As part of the promoting and innovating of the practice of Malagasy traditional medicine, acute and subacute toxicological studies were carried out on Gaertnera phanerophlebia Baker, an endemic species of the RUBIACEAE family. It has been used as a febrifuge and wound healing but there is very little information about its direct toxic effects on organisms. This study aimed to characterize the toxicological profile of the methanolic extract from the aerial parts in male and female mice via oral administration. In vivo experiment indicates that, while the methanolic extract (ST380RF) of the aerial parts has a high acute safety profile (non-toxic up to 5,000 mg/kg of b.w), repeated 28-day exposure at lower doses (5 mg/kg of b.w) caused significant hepatotoxicity and nephrotoxicity, as evidenced by biochemical, hematological and anatomopathological studies of vital organs. These results demonstrate that even if a substance is harmless, its gradual accumulation in the body following repeated exposure over a long period can lead to serious adverse effects that are often impossible to detect until a critical threshold is reached. They also confirm that pharmacological benefits cannot replace comprehensive subacute safety evaluations before human application.