Protective effect of magnesium sulfate on cranial nerves in preeclampsia rats through NF-κB/ICAM-1 pathway

OBJECTIVE The aim of this study was to investigate the protective effect of magnesium sulfate (MgSO4) on the cranial nerves of preeclampsia (PE) rats through the nuclear factor-κB (NF-κB)/intercellular adhesion molecule-1 (ICAM-1) pathway. MATERIALS AND METHODS A total of 30 pregnant rats were randomly divided into three groups, including control group, model group, and treatment group, with 10 rats in each group. Systolic blood pressure was measured at 13 d, 15 d, and 19 d. The apoptosis level in brain tissues was detected via Western blotting and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Protein expression of genes was detected using immunohistochemical staining. Moreover, the messenger ribonucleic acid (mRNA) expressions of NF-κB and ICAM-1 in brain tissues were determined through Reverse Transcription-Polymerase Chain Reaction (RT-PCR). RESULTS Systolic blood pressure exhibited significant differences among the three groups at 15 d and 19 d of gestational age (p<0.05). At 15 d of gestational age, systolic blood pressure was significantly higher in model group than that of control group (p<0.05). However, it was slightly lower in treatment group than model group (p<0.05). At 19 d of gestational age, systolic blood pressure was significantly higher in model group than control group (p<0.05). However, it decreased remarkably in treatment group when compared with model group (p<0.05). In treatment group, systolic blood pressure at 19 d was significantly lower than that at 15 d (p<0.05). Subsequent Western blotting revealed that the protein expression of B-cell lymphoma-2 (Bcl-2) in brain tissues decreased evidently, whereas the expression of Bcl-2 associated X protein (Bax) increased significantly in model group compared with control group, showing statistically significant differences (p<0.01). The protein expression of Bcl-2 in brain tissues increased significantly, while the expression of Bax declined remarkably in treatment group compared with model group (p<0.01). The number of apoptotic cells in model group and treatment group increased significantly compared with that in control group, with the largest in model group (p<0.05). However, it remarkably declined in treatment group compared with model group (p<0.05). These results suggested that MgSO4 treatment could significantly reduce neuronal apoptosis in PE rats. According to the results of immunohistochemistry, the protein expressions of NF-κB and ICAM-1 in brain tissues were significantly higher in model group and treatment group than those in control group (p<0.05). However, they were significantly lower in treatment group than model group (p<0.05). RT-PCR results manifested that the mRNA expressions of NF-κB and ICAM-1 in brain tissues exhibited evident differences among the three groups (p<0.05). Model group and treatment group showed significantly up-regulated mRNA expressions of NF-κB and ICAM-1 in brain tissues compared with control group (p<0.05). The highest mRNA expression was observed in model group. However, treatment group exhibited remarkably decreased mRNA expressions of NF-κB and ICAM-1 in brain tissues compared with model group (p<0.05). CONCLUSIONS MgSO4 exerts a protective effect on cranial nerves of PE rats by inhibiting the NF-κB/ICAM-1 signaling pathway.