LTBP1 Gene Expression in the Cerebral Cortex and its Neuroprotective Mechanism in Mice with Postischemic Stroke Epilepsy.

OBJECTIVE: This study aimed at exploring the expression level of LTBP1 in the mouse model of epilepsy. The mechanism of LTBP1 in epileptic cerebral neural stem cells was deeply investigated to control the occurrence of epilepsy with neuroprotection. METHODS: qRT-PCR was conducted for the expression levels of LTBP1 in clinical human epileptic tissues and neural stem cells, as well as normal cerebral tissues and neural stem cells. The mouse model of postischemic stroke epilepsy (PSE) was established by the middle cerebral artery occlusion (MCAO). Then, qRT-PCR was conducted again for the expression levels of LTBP1 in mouse epileptic tissues and neural stem cells as well as normal cerebral tissues and neural stem cells. The activation and inhibitory vectors of LTBP1 were constructed to detect the effects of LTBP1 on the proliferation of cerebral neural stem cells in the PSE model combined with CCK-8. Finally, Western blot was conducted for the specific mechanism of LTBP1 affecting the development of epileptic cells. RESULTS: Racine score and epilepsy index of 15 mice showed epilepsy symptoms after the determination with MCAO, showing a successful establishment of the PSE model. LTBP1 expression in both diseased epileptic tissues and cells was higher than that in normal clinical epileptic tissues and cells. Meanwhile, qRT-PCR showed higher LTBP1 expression in both mouse epileptic tissues and their neural stem cells compared to that in normal tissues and cells. CCK-8 showed that the activation of LTBP1 stimulated the increased proliferative capacity of epileptic cells, while the inhibition of LTBP1 expression controlled the proliferation of epileptic cells. Western blot showed an elevated expression of TGFß/SMAD signaling pathway-associated protein SMAD1/5/8 after activating LTBP1. The expression of molecular MMP-13 associated with the occurrence of inflammation was also activated. CONCLUSION: LTBP1 can affect the changes in inflammation-related pathways by activating the TGFß/SMAD signaling pathway and stimulate the development of epilepsy, and the inhibition of LTBP1 expression can control the occurrence of epilepsy with neuroprotection.

The roles and mechanisms of miR-26 derived from exosomes of adipose-derived stem cells in the formation of carotid atherosclerotic plaque.

Background: This study explored the serum concentrations of miR-26 in patients with carotid atherosclerosis (CAS) and defined the roles and mechanisms of miR-26 derived from the exosomes of adipose-derived stem cells (ADSC-exos). Methods: The carotid artery width was diagnosed by ultrasound examination in patients with different degrees of CAS. The serum levels of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) in patients were detected by biochemistry. The serum levels of miR-26 were determined by quantitative polymerase chain reaction (qPCR). A model of CAS in ApoE-/- mice fed with a rich-fat diet was established to analyze the regulatory effects of serum miR-26 on blood lipids in mice. Adipose mesenchymal stem cell lines transfected with miR-26 were established. The regulatory relationship between the expression levels of inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1ß, and the expression levels of miR-26 in the supernatant of each group of cells was determined by qPCR. The ADSC-exos were extracted from ADSCs and injected into model mice through the tail vein. The therapeutic effect of ADSCs expressing miR-26 on model mice was evaluated by detecting the levels of inflammatory factors and blood lipids in the serum of the mice. Results: The degree of atherosclerosis (AS) was positively associated with the intima-media thickness (IMT) of the carotid artery. The serum levels of miR-26 in patients were inversely correlated with the levels of blood lipids (TC, TG, and LDL-C), and positively correlated with HDL-C levels. Similarly, in the CAS mouse model, the serum levels of miR-26 were inversely correlated with the levels of blood lipids (TC, TG, and LDL-C), and positively correlated with HDL-C level. In ADSCs transfected with miR-26, the miR-26 expression in the cell supernatant was negatively regulated by the expression of inflammatory factors, TNF-α, IL-6, and IL-1ß, in the cell supernatant. ADSC-exos expressing miR-26 has positive effects on correcting blood lipids and inflammatory factors in the mouse model of CAS. Conclusions: miR-26 has an active role in CAS and may be a novel target for the treatment of CAS in the future.

miR-539 Targeting SNAI2 Regulates MMP9 Signaling Pathway and Affects Blood-Brain Barrier Permeability in Cerebrovascular Occlusive Diseases: A Study Based on Head and Neck Ultrasound and CTA.

This study aimed to explore the expression level of miR-539 in the blood-brain barrier permeability induced by cerebrovascular occlusion and its mediated mechanism. Altogether, 48 patients with cerebral vascular occlusion lesions from March 2018 to June 2020 were collected. The expression level of miR-539 in the peripheral blood serum of the subjects was analyzed by qRT-PCR, and the participants were divided into two groups according to the results of head and neck ultrasound and CTA hemodynamics. The MCAO model of cerebral ischemia was established in rats, and the expression level of miR-539 was detected by qRT-PCR in brain tissues of different groups of rats. The effects of miR-539 on the permeability of blood-brain barrier were investigated by intraventricular injection of agomiR-539 and antagomir-539. The model of blood-brain barrier was established by culturing brain microvascular endothelial cells and pericytes in vitro, and the changes of miR-539 expression level and permeability after glucose and oxygen deprivation were detected. The expression level of SNAI2/MMP9 signaling pathway protein in cells was detected by Western blot. Compared with the healthy control group, the expression level of miR-539 in peripheral blood of patients with cerebrovascular occlusive disease decreased significantly, and the expression level of miR-539 in the MCAO rat model decreased and affected the permeability of blood-brain barrier. Glucose and oxygen deprivation treatment in brain microvascular endothelial cells can lead to downregulation of miR-539 expression and affect cell permeability. miR-539 in brain microvascular endothelial cells can target and bind to SNAI2 and participate in the regulation of endothelial cell permeability by affecting the SNAI2/MMP9 signaling pathway. The results of this study suggested that circulating miR-539 in peripheral blood may be a potential marker for predicting blood-brain barrier permeability after ischemic stroke. More detailed studies are needed to determine its diagnostic value.