Molecular and ultrastructure abnormalities in ovaries of Calosoma olivieri collected from Kafr El Zayat, Egypt triggered by heavy metal exposure

Abstract

Heavy metal pollution is one of the main causes of environmental changes. C. olivieri is used as a biomonitoring beetle in a polluted site in the city of Kafr El-Zayat in the province of Al Gharbia in Egypt which houses pesticides and chemicals factories. After analyzing our data, we noticed a significant variation in mRNA expression of MT and HSp70 in the polluted group compared with the control group which indicates the effect of exposure to heavy metals. On the level of ultrastructural examination, the data revealed several abnormalities in semithin and transmission sections as the trophocytes and oocytes in the polluted group undergo degeneration. The ooplasms were clearly seen to vacuolate and dissociate. There were also deteriorated yolk granules seen. The trophocytes in the control group looked like spherical cells with normal nuclear envelopes and agglomerated chromatin in the nucleus. On the other hand, there were some cellular deteriorations in the polluted group. Occasionally, aberrant nuclei with a defined or intended nuclear envelope were observed in the FECs.