• 한국식품위생안전성학회지
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• 제15권1호
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• pp.41-45
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• 2000

Induction of DNA fragmentation of rat embryonic midbrain cells was studied to see whether apoptosis plays a role in OTA-induced microcephaly observed in cultured rat whole embryos during embryogenesis. We first cultured whole embryos (prepared from day 9.5 gestation rats) for 48 hrs with OTA and found that OTA induced microcephaly in cultured rat whole embryos. We also examined whether the microcephaly seen in cultured whole embryos is partially related to the increase of apoptosis of undifferentiated embryonic midbrain cells. Embryonic midbrain cells were prepared from day 12 gestation rat embryos, and cultured in the mixture media of Dulbecco's modified eagle's medium nutrient and Ham's F12 (1：1) containing 10% Nuserum, 100 $\mu\textrm{g}$/ml of streptomycin and 100 units/ml of penicillin for 96 hrs. Induction of DNA fragmentation was increased by 0.25-1 $\mu\textrm{g}$/ml OTA in a dose dependent manner in the embryonic midbrain cells. We also tested whether increase of apoptosis by OTA would be associated with change of apoptosis-related proteins (TNF-$\alpha$ and P$^{53}$ ) level in embryonic midbrain cells. OTA also increased TNF-$\alpha$ and P$^{53}$ levels. These results show that OTA induced microcephaly in cultured whole embryos and this effect may be at least a part due to the induction of apoptosis and apoptosis-related protein levels of undifferentiated embryonic midbrain cells.

• Journal of Microbiology and Biotechnology
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• 제18권9호
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• pp.1590-1598
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• 2008

Cell proliferation and differentiation are critical processes in a developing fetal rat brain, during which programmed cell death (PCD) also plays an important role. One of the decisive factors for PCD is Bcl-2 family proteins, where Bax induces cell death, whereas Bcl-2 acts as an inhibitor of PCD. As maternal drinking is known to cause fetal alcohol syndrome (FAS) or malformation of the fetal brain during pregnancy, the objective of the present study was to investigate whether maternal ethanol exposure alters the PCD-related Bax and Bcl-2 protein expression during fetal brain development. Pregnant female rats were orally treated with 10% ethanol and the subsequent expressions of the Bax and Bcl-2 proteins examined in the fetal brain, including the forebrain, midbrain, and hindbrain, from gestational day (GD) 15.5 to GD 19.5, using Western blots, in situ hybridization, and immunohistochemistry. With regard to the ratio of Bcl-2 to Bax proteins (Bcl-2/Bax), the Bax protein was dominant in the forebrain and midbrain of the control GD 15.5 fetuses, except for the hindbrain, when compared with the respective ethanol-treated groups. Moreover, Bcl-2 became dominant in the midbrain of the control GD 17.5 fetuses when compared with the ethanol-treated group, representing an alternation of the natural PCD process by ethanol. Furthermore, a differential expression of the Bcl-2 and Bax proteins was found in the differentiating and migrating zones of the cortex, hippocampus, thalamus, and cerebellum. Thus, when taken together, the present results suggest that ethanol affects PCD in the cell differentiation and migration zones of the prenatal rat brain by modulating Bax and Bcl-2 expression in an age- and area-dependent manner. Therefore, this is the first evidence that ethanol may alter FAS-associated embryonic brain development through the alteration of Bax and Bc1-2 expression.