Hydroxychloroquine reduces hypertension and soluble fms-like kinase-1 in a Nω-nitro-l-arginine methyl ester-induced preeclampsia rat model.

OBJECTIVE: Hydroxychloroquine, a drug used for malaria and autoimmune diseases reportedly has beneficial effects against preeclampsia in pregnant women with lupus. However, its mechanism against preeclampsia remains unclear. We investigated the effect of hydroxychloroquine on an Nω-nitro-l-arginine methyl ester-induced preeclampsia rat model. METHODS: Pregnant Sprague-Dawley rats were divided into four groups based on treatment (administered on gestational days 7-18): control, Nω-nitro-l-arginine methyl ester, hydroxychloroquine, and Nω-nitro-l-arginine methyl ester plus hydroxychloroquine. All animals were sacrificed on gestational day 19. We assayed tube formation and determined reactive oxygen species levels using human umbilical vein endothelial cells. RESULTS: Results showed that hydroxychloroquine significantly lowered mean systolic blood pressure (P  < 0.05) in Nω-nitro-l-arginine methyl ester-treated rats. Hydroxychloroquine did not affect their fetal and placental weights. Hydroxychloroquine mitigated Nω-nitro-l-arginine methyl ester-associated changes in proteinuria (P  < 0.05). It normalized plasma soluble fms-like kinase-1 (P  < 0.05) and endothelin-1 (P  < 0.01) levels. In the tube formation assay, hydroxychloroquine increased the total meshes area (P  < 0.05) and mitigated Nω-nitro-l-arginine methyl ester-induced reactive oxygen species formation (P  < 0.05) in human umbilical vein endothelial cells. CONCLUSION: We conclude that hydroxychloroquine alleviated hypertension, proteinuria, and normalized soluble fms-like kinase-1 and endothelin-1 levels in our preeclampsia model and that these changes may involve the restoration of endothelial dysfunction; thus, hydroxychloroquine could potentially be used for preventing preeclampsia, even in the absence of lupus.

Effect of hydroxychloroquine and chloroquine on syncytial differentiation and autophagy in primary human trophoblasts.

During placentation, cytotrophoblasts differentiate and fuse to form multinucleated cells (syncytiotrophoblasts) in a process that involves autophagy. Appropriate syncytial differentiation is essential for establishing a healthy pregnancy. In this study, we evaluated the effect of two chloroquine compounds, hydroxychloroquine (HCQ) and chloroquine (CQ), on syncytial differentiation and autophagy in cultured primary human trophoblasts (PHTs). PHT cells were isolated from the human term placenta. Bafilomycin, a well-known autophagy inhibitor, was used as a positive control. Biochemical and morphological differentiation was assessed in syncytiotrophoblasts, and autophagy-related proteins and genes were evaluated. Affymetrix Human Gene 2.0 ST Array profiling was used to identify genes affected by HCQ during syncytial differentiation. Chloroquine compounds lowered the production of beta-human chorionic gonadotropin (ß-hCG) and the fusion index in PHTs. Syncytial differentiation in PHT was associated with the increased expression of ATG4C mRNA (autophagy-related gene), and this expression was affected by CQ but not by HCQ. Microarray analysis revealed that HCQ or CQ affected several genes (MMP15, GPC3, CXCL10, TET-1, and S100A7) during syncytial differentiation, which were different from that of the syncytial differentiation suppression (Ham's/Waymouth media) or autophagy inhibition (bafilomycin treatment). Using Kyoto Encyclopedia of Genes and Genomes analysis we identified that HCQ might affect JAK2 signaling in the syncytial differentiation of PHT. In conclusion, chloroquine compounds could mitigate biochemical and morphological syncytial trophoblast differentiation in cultured PHT cells through the JAK signaling pathway rather than the inhibition of autophagic activity.