AQP8 may affect glioma proliferation and growth by regulating GSK-3ß phosphorylation and nuclear transport of ß-catenin.

PURPOSE: The purpose of this work is to examine the impact of AQP8 on the proliferation and development of human glioma cell lines A172 and U251 and to determine if aquaporin 8 (AQP8) is associated with GSK-3ß phosphorylation and nuclear transport of ß-catenin in the Wnt signaling pathway. METHODS: AQP8 knockdown cell lines were constructed using a CRISPR/Cas9 double vector lentivirus infection. SAM/dCas9 was used to construct AQP8 overexpression cell lines and the CV084 lentivirus vector was used to construct AQP8 rescue cell lines. AQP8 and its mRNA, and phosphorylated GSK-3ß, ß-catenin, and other related proteins, were detected using western blot and qRT-PCR. Glioma cell apoptosis was detected using Hoechst 33342 dye. The migration of glioma cells was discovered using a wound healing assay. ß-catenin localization in cells was detected using immunofluorescence staining. RESULTS: The proliferative and migratory capacities of A172 and U251 cells were significantly enhanced after AQP8 overexpression. The Wnt signaling pathways appeared to have higher levels of phosphorylated GSK-3ß and ß-catenin, and a rise in the fluorescence intensity ratio of ß-catenin in the nucleus and cytoplasm, which suggests that ß-catenin translocated into the nucleus, while AQP8 knockdown produced the opposite effect. Further, overexpression of AQP8 in AQP8 knockdown cell lines rescued the reduction of related protein levels caused by AQP8 knockdown. CONCLUSION: High AQP8 expression promotes proliferation and growth of glioma cells, a process associated with phosphorylation of GSK-3ß and nuclear translocation of ß-catenin.

Effect of cryopreservation on A172 and U251 glioma cells infected with lentiviral vectors designed for CRISPR/Cas9-mediated aquaporin-8 knock-out.

Among the three existing targeted gene editing technologies, zinc-finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats-CRISPR-associated 9 (CRISPR-Cas9), the latter is widely used owing to its simplicity, efficiency, and low cost. Here, we routinely infected A172 and U251 cells with lentiviral vectors, in which aquaporin-8 (AQP8) was knocked out using CRISPR/Cas9. Our results indicated that cryopreservation did not significantly alter the viral infection efficiency, but influenced AQP8 expression in the infected cells at both protein and mRNA levels compared with the non-cryopreserved samples. Further, AQP8 expression at protein and mRNA levels in recovered cryopreserved infected cells did not significantly differ from those in the blank and negative controls, indicating that the lentivirus was still infectious at low temperatures. However, it failed to release the AQP8-targeting guide RNA in the infected cells, or the guide RNA was released, but underwent changes that caused it to malfunction in the cells with CRISPR/Cas9-mediated AQP8 knock-out. Our findings possibly provide some insights into the reliability of lentiviruses as CRISPR/Cas9 vectors.

[Comparative analysis of electroacupuncture, metformin and their combination on cognitive function and senile plaques of cerebral cortex and hippocampus in APP/PS1 mice].

OBJECTIVE: To compare the effect of electroacupuncture (EA), metformin and EA plus metformin on the cognitive ability and senile plaques (SPs) in cerebral cortex and hippocampus of Alzheimer's disease (AD) mice, so as to explore a better treatment method for AD. METHODS: Twenty-four male APP/PS1 mice were randomly divided into model, metformin (medication), EA and EA+medication groups, with 6 mice in each group. Other 6 male wild C57 mice were used as the control group. EA (2 Hz, 1.0 mA) was applied to "Baihui" (GV20) and "Shenshu" (BL23) for 15 min, once a day, for 4 weeks, with 1 day's off every week. The mice of the medication group received gavage of metformin (300 mg·kg-1·d-1) once a day for 4 weeks. Morris water maze tests were used to assess the cognitive function of mice. H.E. staining was used to observe the histopathological changes of neurons in the cortex and hippocampus. Immunohistochemical method was used to observe the cerebral cortex and hippocampal SPs. The expression levels of SPs formation-related proteins: ß-site amyloid precursor protein cleaving enzyme 1(ßACE1) and insulin-degrading enzyme (IDE) in the cortex and hippocampus were detected by Western blot. RESULTS: Compared with the control group, the escape latency, number of SPs and the expression of ßACE1 in the cortex and hippocampus were ob-viously increased (P<0.01), and the times of platform quadrant crossing and the expression of IDE protein were markedly decreased in the model group (P<0.01). In comparison with the model group, the escape latency, and the number of SPs and expression of ßACE1 proteins in the cortex and hippocampus in the 3 treatment groups were significantly down-regulated (P<0.01), while the times of platform quadrant crossing, and the expression of IDE protein in both cortex and hippocampus of the three treatment groups were considerably up-regulated (P<0.01). Comparison among the three treatment groups showed that the therapeutic effect of EA+medication was significantly superior to that of medication and simple EA in down-regulating the escape latency, the number of SPs and expression of ßACE1 in the cortex and hippocampus (P<0.01), and in up-regulating the times of the platform quadrant crossing, and expression of IDE protein in both cortex and hippocampus (P<0.01). No significant differences were found between the simple medication and simple EA in all the indexes mentioned above (P>0.05). CONCLUSION: EA, metformin and EA plus metformin can improve cognitive ability and relieve SP formation in cerebral cortex and hippocampus in AD mice, which may be associated with their functions in down-regulating the expression of ßACE1 and up-regulating the expression of IDE. The therapeutic effects of EA plus metformin are apparently better than those of simple EA and simple metformin.

[Effect of electroacupuncture on the expression of insulin signal pathway related proteins in hippocampus in mice with Alzheimer's disease].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the expression of insulin phosphatidylinositol-3 kinase/glycogen synthetase kinase-3α (PI3K/GSK3α) signal pathway related proteins in the hippocampus in mice with Alzheimer's disease (AD), and to explore the regulatory mechanism of EA on improving the pathological characteristics of AD. METHODS: Twelve male APP/PS1 double transgenic mice were randomly divided a model group and a treatment group, 6 mice in each group; another 6 wild-type male mice were taken as the control group. The mice in the treatment group were treated with EA (continuous wave, 2 Hz of frequency) at "Baihui" (GV 20) and bilateral "Shenshu" (BL 23), once a day; 7-day treatment was taken as a course of treatment, and 2 courses of treatment were given. The immunohistochemistry method and Western blot method were used to detect the distribution and expression level of hippocampal PI3K/GSK3α signal pathway related proteins P85α, P110α, GSK3α and pS21GSK3α, and the number of hippocampal senile plaques (SP) was observed. RESULTS: The proteins of P85α, P110α, GSK3α and pS21GSK3α were mainly distributed in the cytoplasm of hippocampal neurons, and the GSK3α was also distributed in the axons of neurons in the model group and the treatment group. The immunohistochemistry results showed that the distribution level of GSK3α in the hippocampus in the model group was significantly higher than that in the control group (P<0.001), and the distribution level of pS21GSK3α, P85α and P110α was significantly decreased (P<0.01, P<0.001); compared with the model group, the distribution level of GSK3α in the hippocampus in the treatment group was significantly decreased (P<0.001), and the distribution level of pS21GSK3α, P85α and P110α in hippocampus was significantly increased (P<0.05, P<0.001). The Western blot results showed compared with the control group, the expression of pS21GSK3α, P85α and P110α as well as the ratio of pS21GSK3α/GSK3α in the hippocampus in the model group were significantly decreased (P<0.001), and the expression of GSK3α was increased (P<0.05); compared with the model group, the expression of pS21GSK3α, P85α, P110α and the ratio of pS21GSK3α/GSK3α in the hippocampus in the treatment group were significantly increased (P<0.01, P<0.001), and the expression of GSK3α was decreased (P<0.05). Compared with the control group, the number of hippocampal SP in the model group was significantly increased (P<0.001); compared with the model group, the number of hippocampal SP in the treatment group was significantly decreased (P<0.01). CONCLUSION: EA could effectively regulate the expression of PI3K/GSK3α signal pathway related proteins in the hippocampus in mice with AD, so as to reduce the formation and deposition of SP.