CLDN3 expression and function in pregnancyinduced hypertension

This aim of the present study was to investigate the expression and function of claudin 3 (CLDN3) in pregnancyinduced hypertension. The mRNA expression levels of CLDN3 in the placental tissue and peripheral blood of patients with pregnancyinduced hypertension were measured using reverse transcriptionquantitative PCR. Human trophoblast HTR8/SVneo cells overexpressing CLDN3 were generated using a lentiviral vector. Cell Counting kit8 (CCK8) assay, flow cytometry, Transwell chamber assays, confocal laser scanning microscopy and western blot analysis were performed to detect cell proliferation, invasion, migration and apoptosis, in addition to matrix metalloproteinase (MMP) expression and ERK1/2 phosphorylation. The mRNA expression levels of CLDN3 were significantly reduced in the placental tissues and peripheral blood samples of patients with pregnancyinduced hypertension compared with healthy pregnant controls. CLDN3 overexpression significantly increased HTR8/SVneo cell proliferation, invasion and migration whilst reducing apoptosis. HTR8/SVneo cells overexpressing CLDN3 also exhibited increased myofiber levels, increased MMP2 and MMP9 expression and increased ERK1/2 signaling activity. CLDN3 downregulation may be associated with the pathogenesis of pregnancyinduced hypertension. In conclusion, CLDN3 promotes the proliferative and invasive capabilities of human trophoblast cells, with the underlying mechanisms possibly involving upregulation of MMP expression via the ERK1/2 signaling pathway.