Effect of prenatal exposure of green tea extract on the developing central nervous system of rat fetuses; histological, immune-histochemical and ultrastructural studies

Abstract

Although, several health benefits were associated with green tea, these effects may be beneficial up to a certain dose. Higher doses of green tea may cause several adverse effects. So, there is a need to test the potential negative effects of green tea during pregnancy. This study was designated to evaluate the effect of prenatal exposure of green tea extract on the development of the central nervous system of 20-day old rat fetuses. The pregnant rats were divided into 4 groups; the control group (received distal water) and the other 3 groups received green tea extract at different doses (200, 600 & 1000 mg/kg/day, respectively) from the 6th to 15th day of gestation i.e., during the organogenesis phase of development. Cerebral cortex, cerebellum and spinal cord specimens were subjected to histological, immunohistochemical and ultrastructure investigations. The body weight of both mothers and fetuses was significantly decreased in the groups that received 600 and 1000 mg green tea extract. Also, the neuronal tissues displayed various signs of degeneration which were evident with the 600 and 1000 mg doses. Green tea extract also increases the glial fibrillary acidic protein (GFAP) and decreases the proliferating cell nuclear antigen (PCNA) which were directly proportional with increasing the dose. Administration of green tea extract during rat organogenesis period induced various histological, immunohistochemical and ultrastructural degenerative changes in the cerebral cortex, cerebellum and spinal cord of 20-day old rat fetuses. These deleterious changes were directly proportional to increasing the green tea extract dose. Thus, it should be stressed that the effect of green tea is dose-dependent and therefore it can be either beneficial or adverse.

A Proteomics-Based Identification of the Biological Networks Mediating the Impact of Epigallocatechin-3-Gallate on Trophoblast Cell Migration and Invasion, with Potential Implications for Maternal and Fetal Health

“…While the inhibition of cancer cell activities by EGCG is beneficial, the same effects could potentially affect the physiological functions of normal cells and cause negative outcomes. For pregnant women, consuming green tea or purified EGCG is not completely safe or risk-free, as EGCG has been shown to inhibit blastocyst implantation, cause embryonic cytotoxicity, suppress the neural progenitor cells in the embryo, and affect the development of the central nervous system of the fetus [ 8 , 9 , 10 ]. These side effects might arise from EGCG’s inhibitory effect on the cell activities required for fetal development, including cell division and migration, which are crucial for the morphogenesis and development of the fetus [ 8 ].…”