Natural Toxins of Ageratum conyzoides from Hepatic Vein Occlusive Disease Affected Community in Ethiopia

Abstract

Pyrrolizidine alkaloids (PAs) are phytotoxins produced by plants as a secondary metabolite against herbivores. PAs account for acute hepatotoxic, mutagenic, carcinogenic and teratogenic effects in humans and animals. In vivo PA intoxications of humans and animals are well documented all over the globe. The current study investigated the toxicological chemical make-up of Ageratum conyzoides L, collected from North Western Zones of Tigray region of Ethiopia, where episodic outbreak of hepatic veno-occlusive disease (HVOD) occurred. During the episodic outbreak multiple hundred deaths were reported due to PAs intoxications. PAs contamination occurred through food items such as millet in the farm fields. This study has led to take interventional measures against the causative agents to cease the morbidity and mortality. The identified PAs possesses the 1:2 double bond in the pyrrole ring necessary for in vivo activation and subsequent liver intoxications. The presence of Angeloyl-platynecine, Angeloyl-retronecine, and the macrocyclic, Seneciphylline alkaloids in A. conyzoides L. is not known previously. Isolation of the different PAs were realized by column chromatography (CC) with silica gel, sephadex-LH-20 for size exclusion CC and cationexchanger (CE). PA detection was performed by TLC with Ehrlich reaction method of Mattocks and their identification with gas-chromatography/mass-spectrometry (GC-MS) equipped with standard PAs library. PA containing plants and compounds should be under the watchlist to prevent similar outbreaks worldwide.