Identification of a hippocampal lncRNA-regulating network in a natural aging rat model.

BACKGROUND: Dysregulation of long noncoding RNA (lncRNA) expression is related to aging and age-associated neurodegenerative diseases, and the lncRNA expression profile in the aging hippocampus is not well characterized. In the present investigation, the changed mRNAs and lncRNAs were confirmed via deep RNA sequencing. GO and KEGG pathway analyses were conducted to investigate the principal roles of the clearly dysregulated mRNAs and lncRNAs. Subsequently, through the prediction of miRNAs via which mRNAs and lncRNAs bind together, a competitive endogenous RNA network was constructed. RESULTS: A total of 447 lncRNAs and 182 mRNAs were upregulated, and 385 lncRNAs and 144 mRNAs were downregulated. Real-time reverse transcription-polymerase chain reaction validated the reliability of mRNA and lncRNA sequencing. KEGG pathway and GO analyses revealed that differentially expressed (DE) mRNAs were associated with cell adhesion molecules (CAMs), the p53 signaling pathway (SP), phagosomes, PPAR SP and ECM-receptor interactions. KEGG pathway and GO analyses showed that the target genes of the DE lncRNAs were related to cellular senescence, the p53 signaling pathway, leukocyte transendothelial migration and tyrosine metabolism. Coexpression analyses showed that 561 DE lncRNAs were associated with DE mRNAs. A total of 58 lncRNA-miRNA-mRNA target pairs were confirmed in this lncRNA‒miRNA‒mRNA network, comprising 10 mRNAs, 13 miRNAs and 38 lncRNAs. CONCLUSIONS: We found specific lncRNAs and mRNAs in the hippocampus of natural aging model rats, as well as abnormal regulatory ceRNA networks. Our outcomes help explain the pathogenesis of brain aging and provide direction for further research.

Electroacupuncture promotes angiogenesis by regulating miR-142-5p and activating ADAMTS1/PI3K/AKT pathway in ischemic stroke rats. / 电针调控miR-142-5p和ADAMTS1/PI3K/AKTé€šè·¯ä¿ƒè¿›ç¼ºè¡€æ€§è„‘å’ä¸­å¤§é¼ è¡€ç®¡æ–°ç”Ÿçš„æœºåˆ¶ç ”ç©¶.

OBJECTIVES: To observe the effect of electroacupuncture on miR-142-5p and ADAMTS1/PI3K/AKT pathway in rats with ischemic stroke, so as to explore the regulatory mechanism of electroacupuncture on angiogenesis after ischemic stroke. METHODS: This study was divided into two parts. The first part of the experiment：SD rats were randomly divided into sham operation group, model group and electroacupuncture group. There were 20 rats in each group. The middle cerebral artery occlusion (MCAO) rat model was prepared using a modified Longa's method. In the electroacupuncture group, "Shuigou" (GV26) was selected for electroacupuncture intervention (4 Hz/20 Hz) for 30 min each time. The rats in the electroacupuncture group were given electroacupuncture immediately after successful modeling, once a day for 4 times. Hunter score and TTC staining were used to observe the neurological deficits and infarct volumes respectively；HE staining was used to observe the cortical pathological changes；immunohistochemistry was used to determine the changes of cerebral microvascular density. Real-time quantitative PCR and Western blot were used to observe the miR-142-5p expression, mRNA and protein expression levels of ADAMTS1, VEGF, PI3K, AKT, eNOS in ischemic cortex. The second part of the experiment：The rats were randomly divided into electroacupuncture+control group and electroacupuncture+miR-142-5p Antagomir group with 8 rats in each group. MCAO model was established after injection. Electroacupuncture+control group was given 0.9% sodium chloride solution injected into the right ventricle.The rats in the electroacupuncture+miR-142-5p Antagomir group were injected with miR-142-5p inhibitor into the right ventricle 30 min before modeling. Rats in electroacupuncture+control group and electroacupuncture+miR-142-5p Antagomir group were all given the same electroacupuncture treatment. Real-time fluorescence quantitative PCR was used to observe the effect of miR-142-5p Antagomir on the expression of miR-142-5p and ADAMTS1 mRNA. The effect of miR-142-5p Antagomir on ADAMTS1 protein was observed by Western blot. RESULTS: In the first part of the experiment, compared with the sham operation group, the Hunter score in the model group was significantly increased (P<0.01)；the volume of cerebral infarction in the model group was significantly increased (P<0.01)；the degree of brain edema and neuronal necrosis and the density of cerebral microvessels was increased；the cerebral microvascular density was significantly increased (P<0.01)；the expression levels of miR-142-5p and the mRNA expression levels of VEGF, AKT and eNOS were significantly decreased (P<0.01, P<0.05), and the protein expression levels of VEGF, p-AKT and eNOS were significantly down-regulated (P<0.01), while the mRNA expression levels of ADAMTS1 and PI3K, and the protein expression levels of ADAMTS1 and p-PI3K were all up-regulated (P<0.01, P<0.05) in the model group. Compared with the model group, after intervention, the Hunter score in the electroacupuncture group was decreased (P<0.01), the volume of cerebral infarction was significantly decreased (P<0.01)；the degree of brain edema and neuronal necrosis were alleviated；the cerebral microvascular density was significantly increased (P<0.01)；the expression of miR-142-5p and the mRNA expression of VEGF, PI3K, AKT and eNOS were increased (P<0.01), the protein expressions of VEGF, p-PI3K, p-AKT and eNOS were increased (P<0.01, P<0.05), while the mRNA and protein expression of ADAMTS1 were decreased (P<0.05, P<0.01). After injection of miR-142-5p inhibitor, compared with electroacupuncture+control group, the expression of miR-142-5p in electroacupuncture+miR-142-5p Antagomir group was decreased(P<0.05), while the mRNA and protein expression of ADAMTS1 were increased (P<0.01, P<0.05). CONCLUSIONS: Electroacupuncture at GV26 can improve the neurological damage of ischemic stroke rats, reduce the volume of cerebral infarction and promote angiogenesis. The mechanism may be associated with the function of electroacupuncture in promoting the expression of miR-142-5p, so as to inhibit the expression of its target gene ADAMTS1, mediate the up-regulation of VEGF expression, activate PI3K/AKT pathway, promote the release of eNOS, and participate in promoting angiogenesis in ischemic stroke rats.

Electroacupuncture Promotes Angiogenesis in Mice with Cerebral Ischemia by Inhibiting miR-7.

OBJECTIVE: To observe the angiogenesis effect of electroacupuncture (EA) at Shuigou acupoint (GV 26) in the treatment of cerebral ischemia, and explore the value of miRNA-7 (miR-7) in it. METHODS: First, 48 mice were randomly divided into sham operation, middle cerebral artery occlusion (MCAO) model, and EA treatment groups. Then 9 mice were divided into carrier control group, miR-7 knockout group and miR-7 overexpression group (n=3 each group). Finally, 20 mice were divided into model and carrier control group, model and miR-7 knockout group, EA treatment and carrier control group and EA treatment and miR-7 overexpression group, with 3-6 mice in each group. The MCAO model was established in the MCAO and EA groups. Neurological deficit score and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used to evaluate the severity of cerebral ischemia. Hematoxylin-eosin staining was used to describe basic pathological changes. Immunohistochemistry was used to quantify cerebral microvessel density. Real-time PCR and Western blot were used to detect the expression of miR-7 and its downstream target genes Krüppel-like factor 4/vascular endothelial growth factor (KLF4/VEGF) and angiopoietin-2 (ANG-2) in the ischemic cerebral cortex. RESULTS: After EA, neurological deficit scores and infarction volumes decreased, and the density of cerebral microvessels increased. In the MCAO group, miR-7 expression was higher than that in the sham group (P<0.01). After EA at GV 26, miR-7 expression decreased (P<0.01) and the expression of downstream target genes KLF4/VEGF and ANG-2 increased as compared with the MCAO group (P<0.01). After EA combined with overexpression of miR-7, the expression of downstream target genes KLF4/VEGF and ANG-2 decreased compared to the control EA group (P<0.01). After miR-7 knockdown, the expression of KLF4/VEGF and ANG-2 increased (P<0.05 or P<0.01). CONCLUSIONS: EA could promote angiogenesis in MCAO mice likely by inhibiting the expression of miR-7 and relieving inhibition of downstream target genes KLF4/VEGF and ANG-2.

Role of RbBP5 and H3K4me3 in the vicinity of Snail transcription start site during epithelial-mesenchymal transition in prostate cancer cell.

EMT (epithelial-mesenchymal transition) occurs in a wide range of tumor types, and has been shown to be crucial for metastasis. Epigenetic modifications of histones contribute to chromatin structure and result in the alterations in gene expression. Tri-methylation of histone H3 lysine 4 (H3K4me3) is associated with the promoters of actively transcribed genes and can serve as a transcriptional on/off switch. RbBP5 is a component of the COMPASS/ -like complex, which catalyzes H3K4me3 formation. In this study, we found that in the process of TGF-Beta1 induced EMT in the prostate cancer cell line DU145, H3K4me3 enrichment and RbBP5 binding increased in the vicinity of Snail (SNAI1) transcription start site. Knocking-down of RbBP5 notably decreased Snail expression and EMT. Recruitment of RbBP5 and formation of H3K4me3 at Snail TSS during EMT depend on binding of SMAD2/3 and CBP at Snail TSS. This study links the SMAD2/3 signal with Snail transcription via a histone modification - H3K4me3. Furthermore, our research also demonstrates that RbBP5 and even WRAD may be a promising therapeutic candidates in treating prostate cancer metastasis, and that DU145 cells maintain their incomplete mesenchymal state in an auto/ paracrine manner.