Identification of autophagy signaling network that contributes to stroke in the ischemic rodent brain via gene expression

Dysregulated lncRNA and mRNA may promote the progression of ischemic stroke via immune and inflammatory pathways: results from RNA sequencing and bioinformatics analysis

BACKGROUND

Long non-coding RNAs (lncRNAs) are widely involved in gene transcription regulation and which act as epigenetic modifiers in many diseases.

OBJECTIVE

To determine whether lncRNAs are involved in ischemic stroke (IS), we analyzed the expression profile of lncRNAs and mRNAs in IS.

METHODS

RNA sequencing was performed on the blood of three pairs of IS patients and healthy controls. Differential expression analysis was used to identify differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs). Based on the co-expression relationships between lncRNA and mRNA, a series of bioinformatics analysis including GO and KEGG enrichment analysis and PPI analysis, were conducted to predict the function of lncRNA.

RESULTS

RNA sequencing produced a total of 5 DElncRNAs and 144 DEmRNAs. Influenza A pathway and Herpes simplex infection pathway were the most significant pathways. EP300 and NFKB1 were the most important target proteins, and Human leucocyte antigen (HLA) family were the key genes in IS.

CONCLUSIONS

Analysis of this study revealed that dysregulated lncRNAs in IS may lead to IS by affecting the immune and inflammation system.

Buyang Huanwu Decoction promotes neurogenesis via sirtuin 1/autophagy pathway in a cerebral ischemia model

Stroke is one of the main causes of disease-related mortality worldwide. Buyang Huanwu Decoction (BHD) has been used to protect against stroke and stroke-induced disability for several years in China. Studies have shown that BHD can relieve neuronal damage in rats with cerebral ischemia/reperfusion (I/R) injury. However, the mechanism remains unclear. A middle cerebral artery occlusion and reperfusion (MCAO-R) model was used in the present study. The animals were treated with BHD (5, 10 and 20 g/kg) or rapamycin. Infarct size and modified neurological severity score were calculated on day 5 following MCAO-R surgery. Cellular changes around the ischemic penumbra were revealed by hematoxylin and eosin and Nissl staining. The protein expression levels of nestin, brain-derived neurotrophic factor (BDNF), doublecortin on the X chromosome (DCX) and autophagy-related proteins (beclin 1, LC3-II and p62) in the peri-ischemic area of the brain were detected. The results demonstrated that post-surgical treatment with BHD reduced the brain infarct size and improved neurological deficits in MCAO-R rats. BHD protected against MCAO-R-induced neuronal impairment and promoted neurogenesis, increased the protein expression of nestin, BDNF and DCX and markedly enhanced autophagy by increasing beclin 1 and LC3-II and decreasing p62. Meanwhile, BHD promoted the expression of sirtuin 1 (SIRT1), an important regulator of autophagy. In conclusion, the present study suggested that post-surgical treatment with BHD could protect rat brains from I/R injury, potentially through the SIRT1/autophagy pathway.

Targeting Common Signaling Pathways for the Treatment of Stroke and Alzheimer's: a Comprehensive Review

Neurodegenerative diseases such as stroke and Alzheimer's disease (AD) are two inter-related disorders that affect the neurons in the brain and central nervous system. Alzheimer's is a disease by undefined origin and causes. Stroke and its most common type, ischemic stroke (IS), occurs due to the blockade of cerebral blood vessels. As an important feature, both of disorders are associated with irreversible damages to the brain and nervous system. In this regard, finding common signaling pathways and the same molecular origin between these two diseases may be a promising way for their solution. On the basis of literature appraisal, the most common signaling cascades implicated in the pathogenesis of AD and stroke including notch, autophagy, inflammatory, and insulin signaling pathways were reviewed. Furthermore, current therapeutic strategies including natural and synthetic pharmaceuticals aiming modulation of respective signaling factors were scrutinized to ameliorate neural deficits in AD and stroke. Taken together, digging deeper in the common connections and signal targeting can be greatly helpful in understanding and unified treating of these disorders.

Naringin Targets NFKB1 to Alleviate Oxygen-Glucose Deprivation/Reoxygenation-Induced Injury in PC12 Cells Via Modulating HIF-1α/AKT/mTOR-Signaling Pathway

This study was designed to investigate the effect of naringin in oxygen-glucose deprivation/reoxygenation (OGD/R) model and its mechanism. The target gene of naringin and the enriched pathways of the gene were searched and identified using bioinformatics analysis. Then OGD/R model was built using PC12 cells, after which the cells were treated with different concentrations of naringin. Subsequently, cell proliferation and apoptosis were evaluated by cell counting kit-8 (CCK-8) and flow cytometry assays, respectively. Meanwhile, the expression of NFKB1 in PC12 cells underwent OGD/R-induced injury was detected by qRT-PCR, while apoptosis-related and pathway-related proteins were checked by Western blot. DCF-DA kit was utilized to measure the level of ROS. Our results revealed that NFKB1, which was upregulated in MACO rats and OGD/R-treated PC12 cells, was a target gene of naringin. Naringin could alleviate OGD/R-induced injury via promoting the proliferation, and repressing the apoptosis of PC12 cells through regulating the expression of NFKB1 and apoptosis-associated proteins and ROS level. Besides, the depletion of NFKB1 was positive to cell proliferation but negative to cell apoptosis. Moreover, the depletion of NFKB1 enhanced the influences of naringin on cell proliferation and apoptosis as well as the expression of apoptosis-related proteins and ROS level. Western blotting indicated that both naringin treatment and depletion of NFKB1 could increase the expression of HIF-1α, p-AKT, and p-mTOR compared with OGD/R group. What's more, treatment by naringin and si-NFKB1 together could significantly increase these effects. Nevertheless, the expression of AKT and mTOR among each group was almost not changed. In conclusion, naringin could prevent the OGD/R-induced injury in PC12 cells in vitro by targeting NFKB1 and regulating HIF-1α/AKT/mTOR-signaling pathway, which might provide novel ideas for the therapy of cerebral ischemia-reperfusion (I/R) injury.

Dual Functions of Microglia in Ischemic Stroke

Ischemic stroke is a leading cause of morbidity and mortality worldwide. Resident microglia are the principal immune cells of the brain, and the first to respond to the pathophysiological changes induced by ischemic stroke. Traditionally, it has been thought that microglial activation is deleterious in ischemic stroke, and therapies to suppress it have been intensively explored. However, increasing evidence suggests that microglial activation is also critical for neurogenesis, angiogenesis, and synaptic remodeling, thereby promoting functional recovery after cerebral ischemia. Here, we comprehensively review the dual role of microglia during the different phases of ischemic stroke, and the possible mechanisms controlling the post-ischemic activity of microglia. In addition, we discuss the dynamic interactions between microglia and other cells, such as neurons, astrocytes, oligodendrocytes, and endothelial cells within the brain parenchyma and the neurovascular unit.

Integrated analysis of ischemic stroke datasets revealed sex and age difference in anti-stroke targets

Ischemic stroke is a common neurological disorder and the burden in the world is growing. This study aims to explore the effect of sex and age difference on ischemic stroke using integrated microarray datasets. The results showed a dramatic difference in whole gene expression profiles and influenced pathways between males and females, and also in the old and young individuals. Furthermore, compared with old males, old female patients showed more serious biological function damage. However, females showed less affected pathways than males in young subjects. Functional interaction networks showed these differential expression genes were mostly related to immune and inflammation-related functions. In addition, we found ARG1 and MMP9 were up-regulated in total and all subgroups. Importantly, IL1A, ILAB, IL6 and TNF and other anti-stroke target genes were up-regulated in males. However, these anti-stroke target genes showed low expression in females. This study found huge sex and age differences in ischemic stroke especially the opposite expression of anti-stroke target genes. Future studies are needed to uncover these pathological mechanisms, and to take appropriate pre-prevention, treatment and rehabilitation measures.