Problem Earlier, we showed that calpain activated by increasing intracellular calcium ion concentration in endometrial cells, causes endometrial dysfunction for implantation and early pregnancy. In the present study, we investigated the existence and distribution of calpains, calpastatin, integrin β3 and α-fodrin in decidua from patients with recurrent miscarriage.
Method of study Deciduae were surgically collected from 29 patients with recurrent miscarriage and 20 healthy women with informed consent. Immunohistochemistry, sodium dodecyl sulphate–polyacrylamide gel electrophoresis, and western blot analysis were performed.
Results Staining of μ-calpain, m-calpain, calpastatin, integrin β3 and α-fodrin were observed in the cytoplasm of stromal and epithelial cells in decidua using immunohistochemistry. No significant differences were observed in staining patterns. Western blot analysis showed no significant differences in expression of m-calpain, calpastatin and α-fodrin, whereas μ-calpain was significantly higher and integrin β3 was lower in subject.
Conclusion The results suggest that cleavage of integrin β3 by μ-calpain may have an adverse effect on the mechanism of early pregnancy.