In vivo and in silico investigations of the toxicological and analgesic properties of unprocessed Aloe vera gel in experimental rat models

Abstract

Aloe vera is a commonly used plant in both food and medicine industry. The potential toxicological side-effects of prolonged intake of Aloe extract have not been evaluated in detail. This work presents an in-depth toxicological study of the crude unprocessed A. vera gel in experimental rats. Acute and sub-chronic toxicity was evaluated in a 1 to 28-day long feeding schedule of the aqueous homogenized gel material. Hemoglobin, total protein, high density lipoprotein (HDL), low density lipoprotein (LDL), cholesterol, triglyceride, serum creatinine, serum alanine transaminase (SGPT), aspartate transaminase (SGOT) and alkaline phosphatase were examined and kidney and liver histology was performed. In the acute toxicity test, the behavioral aspects were also considered. A molecular docking assay was performed to investigate the binding affinities of pure A. vera compounds with liver and kidney toxicological marker enzymes, in order to assess the probable mode of action of selected Aloe constituents. Solubility factors for the active constituents were also studied to determine their possible miscibility with body fluids. The results from in vivo tests provided no major toxicological indications. Crude Aloe gel consumption up to 4 g/kg body weight (b.w.) showed no toxicological side effects. From the structural standpoint, Aloe-based bioactive molecules, such as Aloe-emodin, acetophenone, ?-sitosterol, cholestenol and squalene showed promising binding affinity to qualify as alternative and complementary medicines. The synergistic roles of all A. vera constituents remain to be validated in human disease models.