Acute Impact of the Artificial Sweetener Aspartame on the Ultrastructures of Hepatocyte in Mice

Abstract

A non-saccharide artificial sweetener, aspartame (L-aspartyl-L-phenylalanine methyl ester) is used worldwide as a sugar substitute in many foods and beverages. The objective of this work was to clarify the acute impact of various doses of daily ingestion of Aspartame at the cellular level of the liver tissues in mice. Sixty adult male mice were divided into five groups including control fed normal diet and tap water, while other 4 groups (12 each) were daily fed orally with 1 mL of either 40, 500, 1000 and 1500 mg/Kg b.wt. APM dissolved in distilled water using gavages for consecutive 5 weeks. Liver samples fixed in 10% formalin were cut as 5 μ m using Leica microtome and the sections were stained with both routine Heamatoxylene and Eosin (H & E) as well as Transmission electron Microscope (TEM). Histological results showed cellular changes in the hepatic tissues which were proportional with the increased doses. The hepatocytes had developed fatty droplets in the cytoplasm of almost all cells, loss of nuclei, necrosis detectable at LM level. Lymphatic nodules were also generated around the triads and the central hepatic veins as well as intracellular gaps with higher doses. The TEM results demonstrated degradation of mitochondria indicating the direct acute effects of the aspartame on hepatic tissues which all were proportional with the increased doses. It is concluded that the daily ingestion of aspartame, even at lower doses, has acute effects and is dose dependant on hepatic cells which could exert further risks onto other tissues of consumers on the long run.