miR-129-5p targets FEZ1/SCOC/ULK1/NBR1 complex to restore neuronal function in mice with post-stroke depression.

Post-stroke depression (PSD) seriously affects the normal life of patients. Based on the previous sequencing results, this study selected miR-129-5p as the research object, which was significantly reduced in the PSD model by screening. To clarify the regulatory role of miR-129-5p, this study overexpressed and interfered with miR-129-5p in neuronal cells cultured in vitro, tested its effect on neuronal cell autophagy, and determined expressions of fasciculation and elongation protein zeta-1 (FEZ1), short coiled-coil protein (SCOC), unc-51 like autophagy activating kinase 1 (ULK1) and autophagy cargo receptor (NBR1) autophagy-related proteins. The dual-luciferase reporter system and immunoprecipitation were applied to detect the molecular regulatory mechanism of miR-129-5 and FEZ1, SCOC, ULK1 and NBR1. Findings of the present study revealed that the autophagy of neuronal cells was markedly decreased by overexpressing miR-129-5p (p < 0.05), and expressions of FEZ1, SCOC, ULK1 and NBR1 were substantially reduced (p < 0.05). The dual-luciferase reporter system results indicated that FEZ1, SCOC, ULK1 and NBR1 were all miR-129-5p target genes. Furthermore, immunoprecipitation assay revealed that SCOC, ULK1 and NBR1 could directly bind to the FEZ1 protein. The experiments at an animal level demonstrated that miR-129-5p could effectively alleviate the behavioral indicators of PSD model mice. Taken together, this study testified that SCOC/ULK1/NBR1 proteins could directly bind to FEZ1 to form protein complex, and all of the four proteins FEZ1/SCOC/ULK1/NBR1 were miR-129-5p target genes. miR-129-5p overexpression could effectively restore the behavioral characteristics of model mice, and reduce the autophagy-related proteins FEZ1/SCOC/ULK1/NBR1.

Differential expression analysis of microRNAs and mRNAs in the mouse hippocampus of post-stroke depression (PSD) based on transcriptome sequencing.

To clarify the differential expressions of microRNAs and mRNAs in a PSD model, this study employed PSD mice for model construction by injecting vasoconstrictor ET-1 (angioendothelin-1) into the medial prefrontal cortex (mPFC) of mice. The animals underwent elevated plus maze test, open field test, tail suspension test, and forced swimming test subsequently. Transcriptome sequencing was performed to analyze the differentially expressed mRNAs and microRNAs. The results showed that open arm entries and time of PSD mice were markedly decreased. Times of the entry to center for mice in the model group were apparently decreased. The climbing time of mice in the model group was greatly decreased. The behavior of PSD mice indicated a marked change, and several indicators of the behavioral tests were significantly lower than those of the control group. Transcriptome sequencing analysis demonstrated that expressions of 1 206 genes and 21 microRNAs were markedly upregulated in model group, whereas expressions of 2 113 genes and 32 microRNAs were markedly downregulated. GO analysis revealed that the differentially expressed genes were mainly involved in regulatory pathways of single-multicellular organism process, developmental process, cell periphery, plasma membrane, and neuron projection. Meanwhile, KEGG analysis results indicated that the differentially expressed genes mostly participated in signaling pathways of neuroactive ligand-receptor interaction, calcium signaling pathway, and cytokine-cytokine receptor interaction. In conclusion, differentially expressed microRNAs and mRNAs were screened, which offers a theoretical foundation for further investigation of molecular mechanisms and novel insight for the early identification, prevention, and treatment of PSD.

Dynamic Behavior of the Liquid Flow Coalescing with a Droplet in Hydrophobic Microchannels.

In this study, the dynamic behavior of the moving liquid column coalescing with a sessile droplet in a hydrophobic microchannel under pressure driven flow conditions is numerically investigated using coupled Volume of Fluid with Level Set (CLSVOF) interface tracking method implemented in ANSYS-Fluent 14.5 in conjunction with the continuum surface force (CSF) model. Numerical result reveals that the coalescence between the moving liquid column and droplet can accelerate the original liquid column movement. Effects of the wettability, head pressure, and droplet size and position are also investigated. It is found that the velocity increment ratio increases with increasing the contact angle and decreasing the head pressure. Larger droplet and smaller distance between the droplet and inlet can result in a larger velocity increment ratio as a result of higher surface energy and lower viscous dissipation energy. The maximum velocity increment ratio of 0.17 is obtained with a 10000-µm3 droplet that is positioned at 200 µm in a microchannel with 100 µm in width and 300 µm in length and contact angle of 120°.