Chemical Induction of Trophoblast Hypoxia by Cobalt Chloride Leads to Increased Expression of DDIT3

Choriocarcinoma cells BeWo b30 are used to model human placental trophoblast hypoxia using cobalt (II) chloride and hydroxyquinoline derivative (HD) as chemical inducers of hypoxia-inducible factor (HIF). In this study, it was shown that both substances activate the hypoxic pathway and the epithelial–mesenchymal transition and inhibit the pathways of cell proliferation. However, CoCl(2) caused activation of the apoptosis pathway, increased the activity of effector caspases 3 and 7, and increased the expression of the unfolded protein response target DDIT3. The mTORC1 pathway was activated upon exposition to CoCl(2), while HD suppressed this pathway, as it happens during real trophoblast hypoxia. Thus, effect of CoCl(2) on BeWo cells can be a model of severe hypoxia with activation of apoptosis, while HD mimics moderate hypoxia.