Morphostructural and immunohistochemical study on the role of metallothionein in the detoxification of heavy metals in Apis mellifera L., 1758

Honey is a valuable food produced by bees from sugary substances that they gather in nature. The action taken by the bee to transform the nectar into honey is long and complex. Except for honey, where heavy metals are absent or are found only in trace amounts, the bees and their products have always been considered excellent biomarkers of such contaminants. We have assumed that the absence of heavy metals in honey is due to the presence a detoxification system at the level of the digestive system of bees, which could include the use of metallothionein, proteins that have a role in the homeostatic control of metals essential and nonessential. We have placed the hives in three different zones, an industrial zone, an area to the city center and a rural control area. Investigations were conducted with ICP-MS for the detection of heavy metals in the intestines of honey bee forangers and honey, the metallothioneins have been identified by immunohistochemical and Western-blotting analisys. Investigations conducted by ICP-MS on samples taken in three different areas not have never shown significant differences in the content of heavy metals, while the presence of metallothionein has been highlighted only in epithelium of the honey sac, demonstrating the existence of an efficient system of detoxification of heavy metals.