Objective:To investigate the effect of gap junction protein Cx43 inhibitor carbenoxolone (CBX) on cognitive function and its possible mechanism in epileptic rats.Methods:One hundred and twenty Wistar rats were randomly divided into sham-operated group, epilepsy group, epilepsy+solvent group, and epilepsy+CBX group ( n=30). The models of temporal lobe epilepsy in the later three groups were prepared by injection of kainic acid in the hippocampus. Intraperitoneal injection of CBX (20 mg/kg) or equal amount of normal saline were given to the rats in the epilepsy+CBX group and epilepsy+solvent group 30 min before modeling. Western blotting was used to detect the protein expressions of phosphorylated (p)-Cx43 and microtubule associated protein light chain 3 (LC3) in the hippocampus 6, 12, and 24 h after modeling; the protein localization of p-Cx43 and LC3 in the hippocampus and optical density of their positive cells were detected by immunohistochemistry 24 h after modeling; the learning and memory abilities of rats were tested by Morris water maze experiment 30 d after modeling. Results:Western blotting results showed that as compared with those in the sham-operated group, p-CX43 and LC3 protein expressions in the hippocampal CA3 regions of epilepsy group and epilepsy+solvent group were significantly increased at 6, 12 and 24 h after modeling ( P<0.05); as compared with the epilepsy group and epilepsy+solvent group, the epilepsy+CBX group had statistically decreased p-CX43 and LC3 protein expressions in the hippocampal CA3 regions at each time point ( P<0.05). Immunohistochemical staining showed that p-CX43 was localized at the cell membrane and cytoplasm of hippocampal astrocytes; LC3 was located at the cytoplasm of hippocampal neurons. As compared with those in the sham-operated group, the optical density values of p-CX43 and LC3 positive cells in hippocampal CA3 regions of epilepsy group and epilepsy+solvent group were increased ( P<0.05). As compared with those in the epilepsy group and the epilepsy+solvent group, the optical density values of p-CX43 and LC3 positive cells in the hippocampal CA3 regions of the epilepsy+CBX group were significantly decreased ( P<0.05). Morris water maze test results showed that as compared with that in the sham-operated group, the escape latency in the epilepsy group and epilepsy+solvent group was significantly prolonged ( P<0.05); as compared with that in the epilepsy group and epilepsy+solvent group, the latency in the epilepsy+CBX group was significantly shortened ( P<0.05). Conclusion:CBX can weaken the neuronal autophagy and reduce the damage to cognitive function by inhibiting the p-Cx43 protein expression in the astrocytes of the hippocampal CA3 regions.

Objective To investigate the molecular mechanism of miR-139-5p targeting transforming growth factor-β1 (TGF-β1) in the regulation of epithelial mesenchymal transition (EMT),thus inhibiting invasion and metastasis of hepatoma cells.Methods Bioinformatics methods were used to determine whether miR-139-5p was the best binding miRNA of TGF-β1.Correlation between the TGF-β1 expression as detected by immunohistochemistry and Western blot,and the miR-139-5p level by qRT-PCR in 56 hepatoma tissues and 20 normal tissues,respectively,was analyzed.The relationship between the miR-139-5p level as detected by qRT-PCR,and TGF-β1,E-cadherin and Vimentin by Western blot in the high and low metastatic hepatoma cell lines were investigated.In recombinant cell lines,whether miR-139-5p could bind to the 3'UTR site of TGF-β1 was evaluated,and the effect on invasive ability after modulating miR-139-5p level was also tested by the transwell method.Results A total of 20 miRNAs were found to be able to bind with TGF-β1 by bioinformatics methods and among these mRNAs,miR-139-5p was the best target miRNA with the highest specificity and strongest stability to bind TGF-β1.The positive expression rates of TGF-β1 in hepatoma tissues and adjacent normal liver tissues were 80.4％ (45/56) and 15.0％ (3/20),respectively,(P ＜0.05).There were significant differences on the expressions of TGF-β1,E-cadherin and Vimentin among the different metastatic cell lines (all P ＜ 0.05).After miR-139-5p was transfected into hepatoma cells,miR-139-5p could bind to the 3'UTR site of TGF-β1,resulting in downregulating TGF-β1 expression.When compared to the other three groups,the cell line with a high expression of miR-139-5p had a significantly lower count of invasive cells (53 ± 4/high magnification field) (P ＜ 0.05).Conclusion miRNA139-5p could specifically bind to the 3'UTR site of TGF-β1 and regulate the EMT signaling pathway,thus suppressing invasion and metastasis of hepatoma cells.