Toxicological Profile of a Quercus laurina Bark Extract Through Oral Administration: Impact on Hepatocyte Mitochondrial Bioenergetics.

Abstract

Quercus laurina is an oak species used orally in Mexican folk medicine. However, its toxicological profile has not yet been evaluated, which makes it difficult to determine safe doses for traditional preparations. This study, for the first time, evaluates the acute toxicity of an ethanolic extract of Q. laurina bark (QLBE) in Wistar rats in accordance with OECD guideline 423, and it explores the impact of QLBE on mitochondrial bioenergetics and glycolytic capacity in primary hepatocytes to determine whether the extract alters cellular energy metabolism. QLBE at 2000 mg/kg elicited death and tremors, and a dose-dependent hepatic injury, in addition to histopathological changes in the kidney, brain, lung, and heart. QLBE caused a significant reduction in the basal, ATP-linked, spare, and maximal mitochondrial respiratory capacities of hepatocytes, and it decreased glycolytic capacity after 2 and 24 h of exposure. These findings indicate that QLBE disrupts mitochondrial bioenergetics and glycolytic activity in hepatocytes, alterations that may be associated with the observed liver toxicity. HPLC and GC-MS analyses identified myo-inositol, quininic acid, and ellagic acid as the primary metabolites of QLBE. The results demonstrated the toxic potential of QLBE, thereby discouraging its unregulated use in traditional remedies in Mexican folk medicine.