scholarly journals Dexmedetomidine Reduces Propofol-Induced Hippocampal Neuron Injury by Modulating the miR-377-5p/Arc Pathway

Author(s):  
Zong Chen ◽  
Yong Ding ◽  
Ying Zeng ◽  
Xue-Ping Zhang ◽  
Jian-Yan Chen

Abstract BackgroundPropofol and dexmedetomidine (DEX) are widely used in general anesthesia, and exert toxic and protective effects on hippocampal neurons, respectively. The study sought to investigate the molecular mechanisms of DEX-mediated neuroprotection against propofol-induced hippocampal neuron injury in mouse brains.MethodsHippocampal neurons of mice were treated with propofol, DEX, and propofol+DEX in vitro and in vivo. Neuronal apoptosis was evaluated by a means of TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) or Hochest 33258 staining; Arc positive expression in hippocampus tissues was detected using a microscope in immunohistochemistry assays; miRNA-377-5p expression levels were quantified by RT-PCR; the protein levels of Arc, DNMT3A, and DNMT3B were determined using western blot; CCK-8 kit was used to evaluated neuron viability; methylation analysis in miR-377-5p promoter was performed through the methylated DNA immunoprecipitation (MeDIP) assay; luciferase reporter assay was performed to confirm whether Arc was under targeted regulation of miR-377-5p.Results In the current study, both in vitro and in vivo, propofol treatment induced hippocampal neuron apoptosis and suppressed cell viability. DNMT3A and DNMT3B expression levels were decreased following propofol treatment, resulting in lowered methylation in the miR-377-5p promoter region and then enhanced expression of miR-377-5p, leading to a decrease in the expression level of downstream Arc. Conversely, the expression levels of DNMT3A and DNMT3B were increased following DEX treatment, thus methylation in miR-377-5p promoter region was improved, and miR-377-5p expression levels were decreased, leading to an increase in the expression level of downstream Arc. Finally, DEX pretreatment protected hippocampal neurons against propofol-induced neurotoxicity by recover the expression levels of DNMT3A, miR-377-5p, and Arc to the normal levels.ConclusionsDEX reduced propofol-induced hippocampal neuron injury via the miR-377-5p/Arc signaling pathway.

Author(s):  
Yulang Huang ◽  
Lifang Chen ◽  
Zongming Feng ◽  
Weixin Chen ◽  
Shaodi Yan ◽  
...  

Myocardial infarction (MI) remains a leading cause of morbidity and mortality worldwide. Endothelial progenitor cell (EPC)-derived exosomes have been found to be effective in alleviating MI, while the detailed mechanisms remain unclear. The present study aimed to determine the protective effects of EPC-derived exosomal miR-1246 and miR-1290 on MI-induced injury and to explore the underlying molecular mechanisms. The exosomes were extracted from EPCs; gene expression levels were determined by quantitative real-time PCR, and protein expression levels were determined by western blot and immunofluorescence staining, respectively. The angiogenesis and proliferation of human cardiac fibroblasts (HCFs) were determined by tube formation assay and immunofluorescence staining of PKH67, respectively. Luciferase reporter, CHIP, and EMSA assays determined the interaction between miR-1246/1290 and the targeted genes (EFL5 and SP1). The protective effects of miR-1246/1290 on MI were evaluated in a rat model of MI. EPC-derived exosomes significantly upregulated miR-1246 and miR-1290 expression and promoted phenotypic changes of fibroblasts to endothelial cells, angiogenesis, and proliferation in HCFs. Exosomes from EPCs with miR-1246 or miR-1290 mimics transfection promoted phenotypic changes of fibroblasts to endothelial cells and angiogenesis in HCFs, while exosomes from EPCs with miR-1246 or miR-1290 knockdown showed opposite effects in HCFs. Mechanistically, miR-1246 and miR-1290 from EPC-derived exosomes induced upregulation of ELF5 and SP1, respectively, by targeting the promoter regions of corresponding genes. Overexpression of both ELF5 and SP1 enhanced phenotypic changes of fibroblasts to endothelial cells and angiogenesis in HCFs pretreated with exosomes from EPCs with miR-1246 or miR-1290 mimics transfection, while knockdown of both EFL5 and SP1 exerted the opposite effects in HCFs. Both ELF5 and SP1 can bind to the promoter of CD31, leading to the upregulation of CD31 in HCFs. Furthermore, in vivo animal studies showed that exosomes from EPCs with miR-1246 or miR-1290 overexpression attenuated the MI-induced cardiac injury in the rats and caused an increase in ELF5, SP1, and CD31 expression, respectively, but suppressed α-SMA expression in the cardiac tissues. In conclusion, our study revealed that miR-1246 and miR-1290 in EPC-derived exosomes enhanced in vitro and in vivo angiogenesis in MI, and these improvements may be associated with amelioration of cardiac injury and cardiac fibrosis after MI.


2021 ◽  
Vol 12 ◽  
Author(s):  
Guangchan Jing ◽  
Huanyuan Wang ◽  
Fengwei Nan ◽  
Yuqin Liu ◽  
Mengren Zhang

P2X7/NLRP1/caspase-1 mediated neuronal injury plays an important role in diabetic cognitive impairment and eventually inflammatory cascade reaction. Chinese herbal compound Naofucong has been mainly used to treat cognitive disorders in Traditional Chinese Medicine The present study aimed to investigate whether its neuroprotective effects might be related to the inhibition of P2X7R/NLRP1/caspase-1 mediated neuronal injury or not. In this study, high glucose-induced HT22 hippocampal neurons were used to determine Naofucong-containing serum neuronal protective effects. Lentiviruses knock out of TXNIP and P2X7R was used to determine that protective effects of Naofucong was related to inflammatory response and P2X7/NLRP1/caspase-1 mediated neuronal injury. NAC was also used to inhibit oxidative stress, so as to determine that oxidative stress is an important starting factor for neuronal injury of HT22 cells cultured with high glucose. Naofucong decreased apoptosis, IL-1β and IL-18 levels in high glucose-induced HT22 hippocampal neuron cells. Naofucong suppressed NLRP1/caspase-1 mediated neuronal injury, and P2X7 was involved in process. HT22 cells cultured in high glucose had an internal environment with elevated oxidative stress, which could promote neuronal injury. The current study demonstrated that Naofucong could significantly improve high glucose-induced HT22 hippocampal neuron injury, which might be related to suppress P2X7R/NLRP1/caspase-1 pathway, which provides novel evidence to support the future clinical use of Naofucong.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shanshan Liu ◽  
Qing Liu ◽  
Yanjie Ju ◽  
Lei Liu

AbstractThis study aimed to evaluate the role of miR-383 in the regulation of Wnt-2 signaling in the rat model of chronic stress. The male SD rats with depressive-like behaviors were stimulated with chronic unpredictable mild stress (CUMS) including ice-water swimming for 5 min, food deprivation for 24 h, water deprivation for 24 h, stimulating tail for 1 min, turning night into day, shaking for 15 min (once/s), and wrap restraint (5 min/time) every day for 21 days. The expression levels of miRNAs were detected by qRT-PCR, and the expression levels of Wnt2, depression-impacted proteins (GFAP, BDNF, CREB), brain neurotransmitters (5-HT, NE, DA) and apoptosis-related proteins (Bax and Bcl-2) were evaluated by qRT-PCR and western blot. Bioinformatic analysis and luciferase reporter assay were performed to determine the relationship between miR-383 and Wnt2. Ethological analysis was evaluated by sugar preference test, refuge island test and open field tests. Rescue experiments including knockdown of miR-383, overexpression and silencing of Wnt2 were performed to determine the role of miR-383. High expression levels of miR-383 were observed in the hippocampus of rats submitted to CUMS model. Downregulation of miR-383 significantly inhibited the apoptosis and inflammatory response of hippocampal neurons, and increased the expression levels of GFAP, BDNF and CREB which were impacted in depression, as well as neurotransmitters, then attenuated neural injury in rats induced by CUMS. Furthermore, Wnt family member 2 (Wnt2) was identified as a target of miR-383, and silencing of Wnt2 obviously attenuated the protective effect of miR-383 inhibitor on the apoptosis and inflammatory response in hippocampal neurons, as well as neural injury in CUMS-induced rats. Downregulation of miR-383 ameliorated the behavioral and neurochemical changes induced by chronic stress in rats by directly targeting Wnt2, indicating that the miR-383/Wnt2 axis might be a potential therapeutic target for MDD.


2020 ◽  
Vol 40 (9) ◽  
Author(s):  
Jingli Qian ◽  
Guoping Li ◽  
Xiaosheng Jin ◽  
Chunfang Ma ◽  
Wanru Cai ◽  
...  

Abstract Objective: Our aim was to investigate the effect of emodin on intestinal and lung injury induced by acute intestinal injury in rats and explore potential molecular mechanisms. Methods: Healthy male Sprague–Dawley (SD) rats were randomly divided into five groups (n=10, each group): normal group; saline group; acute intestinal injury model group; model + emodin group; model+NF-κB inhibitor pynolidine dithiocarbamate (PDTC) group. Histopathological changes in intestine/lung tissues were observed by Hematoxylin and Eosin (H&E) and terminal deoxynucleotidyl transferase biotin-dUTP nick-end labeling (TUNEL) staining. Serum IKBα, p-IKBα, surfactant protein-A (SP-A) and toll-like receptor 4 (TLR4) levels were examined using enzyme-linked immunosorbent assay (ELISA). RT-qPCR was performed to detect the mRNA expression levels of IKBα, SP-A and TLR4 in intestine/lung tissues. Furthermore, the protein expression levels of IKBα, p-IKBα, SP-A and TLR4 were detected by Western blot. Results: The pathological injury of intestinal/lung tissues was remarkedly ameliorated in models treated with emodin and PDTC. Furthermore, the intestinal/lung injury scores were significantly decreased after emodin or PDTC treatment. TUNEL results showed that both emodin and PDTC treatment distinctly attenuated the apoptosis of intestine/lung tissues induced by acute intestinal injury. At the mRNA level, emodin significantly increased the expression levels of SP-A and decreased the expression levels of IKBα and TLR4 in intestine/lung tissues. According to ELISA and Western blot, emodin remarkedly inhibited the expression of p-IKBα protein and elevated the expression of SP-A and TLR4 in serum and intestine/lung tissues induced by acute intestinal injury. Conclusion: Our findings suggested that emodin could protect against intestinal and lung injury induced by acute intestinal injury by modulating SP-A and TLR4/NF-κB pathway.


2018 ◽  
Vol 20 (1) ◽  
pp. 98 ◽  
Author(s):  
Tingjin Zheng ◽  
Guoxing Ma ◽  
Mingqing Tang ◽  
Zhongwan Li ◽  
Ruian Xu

Prostate cancer (PCa) is a major health problem in males. Metastasis-associated with lung adenocarcinoma transcript-1 (MALAT1), which is overexpressed in PCa tissue, is associated with physiological and pathological conditions of PCa. M2 macrophages are major immune cells abundant in the tumor microenvironment. However, it remains unknown whether M2 macrophages are involved in the effects or not, and molecular mechanisms of MALAT1 on PCa progression have not yet been comprehensively explored. Here we reported that, M2 macrophages (PMA/IL-4 treated THP1) induced MALAT1 expression in PCa cell lines. Knockdown MALAT1 expression level in PCa cell lines inhibited cellular proliferation, invasion, and tumor formation. Further mechanistic dissection revealed that M2 macrophages secreted IL-8 was sufficient to drive up MALAT1 expression level via activating STAT3 signaling pathway. Additional chromatin immunoprecipitation (ChIP) and luciferase reporter assays displayed that STAT3 could bind to the MALAT1 promoter region and transcriptionally stimulate the MALAT1 expression. In summary, our present study identified the IL-8/STAT3/MALAT1 axis as key regulators during prostate tumorigenesis and therefore demonstrated a new mechanism for the MALAT1 transcriptional regulation.


2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Liang Yue ◽  
Lei Zhao ◽  
Haixiao Liu ◽  
Xia Li ◽  
Bodong Wang ◽  
...  

Glutamate- (Glu-) induced excitotoxicity plays a critical role in stroke. This study aimed to investigate the effects of APN on Glu-induced injury in HT22 neurons. HT22 neurons were treated with Glu in the absence or the presence of an APN peptide. Cell viability was assessed using the MTT assay, while cell apoptosis was evaluated using TUNEL staining. Levels of LDH, MDA, SOD, and GSH-Px were detected using the respective kits, and ROS levels were detected using dichlorofluorescein diacetate. Western blot was used to detect the expression levels of silent information regulator 1 (SIRT1), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), cleaved caspase-3, Bax, and Bcl-2. In addition to the western blot, immunofluorescence was used to investigate the expression levels of SIRT1 and PGC-1α. Our results suggest that APN peptide increased cell viability, SOD, and GSH-Px levels and decreased LDH release, ROS and MDA levels, and cell apoptosis. APN peptide upregulated the expression of SIRT1, PGC-1α, and Bcl-2 and downregulated the expression of cleaved caspase-3 and Bax. Furthermore, the protective effects of the APN peptide were abolished by SIRT1 siRNA. Our findings suggest that APN peptide protects HT22 neurons against Glu-induced injury by inhibiting neuronal apoptosis and activating SIRT1-dependent PGC-1αsignaling.


2019 ◽  
Author(s):  
YJ Fan ◽  
XX Li ◽  
Abd Allah A. H. Mohammed ◽  
Y Liu ◽  
Xiwu Gao

Abstract Background: Most aphids exhibit wing polyphenism in which wingless and winged morphs produce depending on the population density and host plant quality. Although the influence of environmental factors on wing polyphenism of aphids have been extensively investigated, molecular mechanisms underlining morph differentiation (i.e. wing development /degeneration), one downstream aspect of the wing polyphenism, has been poorly understood. Results: We examined the expression levels of the twenty genes involved in wing development network, and only vestigial (vg) showed significantly different expression levels in both whole-body and wall-body of third instar nymphs, with 5.4- and 16.14- fold higher expression in winged lines compared to wingless lines, respectively in Rhopalosiphum padi. vg expression was higher in winged lines compared to wingless lines in third, fourth instar nymphs and adults. Larger difference expression was observed in third (21.38-fold) and fourth (20.91-fold) instar nymphs relative to adults (3.12-fold). Suppression of vg using RNAi repressed the wing development of third winged morphs. Furthermore, dual luciferase reporter assay revealed that the miR-147 can target the vg mRNA. Modulation of miR-147b levels by microinjection of its agomir (mimic) decreased vg expression levels and repressed wing development. Conclusions: Our findings suggest that vg is essential for wing development in R. padi and that miR-147b modulates its expression.


2020 ◽  
Author(s):  
YJ Fan ◽  
XX Li ◽  
Abd Allah A. H. Mohammed ◽  
Y Liu ◽  
Xiwu Gao

Abstract Background: Most aphids exhibit wing polyphenism in which wingless and winged morphs produce depending on the population density and host plant quality. Although the influence of environmental factors on wing polyphenism of aphids have been extensively investigated, molecular mechanisms underlining morph differentiation (i.e. wing development /degeneration), one downstream aspect of the wing polyphenism , has been poorly understood. Results: We examined the expression levels of the twenty genes involved in wing development network, and only vestigial (vg ) showed significantly different expression levels in both whole-body and wall-body of third instar nymphs, with 5.4- and 16.14- fold higher expression in winged lines compared to wingless lines, respectively in Rhopalosiphum padi . vg expression was higher in winged lines compared to wingless lines in third, fourth instar nymphs and adults. Larger difference expression was observed in third (21.38-fold) and fourth (20.91-fold) instar nymphs relative to adults (3.12-fold). Suppression of vg using RNAi repressed the wing development of third winged morphs. Furthermore, dual luciferase reporter assay revealed that the miR-147 can target the vg mRNA. Modulation of miR-147b levels by microinjection of its agomir (mimic) decreased vg expression levels and repressed wing development. Conclusions : Our findings suggest that vg is essential for wing development in R. padi and that miR-147b modulates its expression. .


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Baohui Su ◽  
Yanguang Yuan ◽  
Junshan Zhang ◽  
Yuezhong Li ◽  
Qihui Zhang

Objective. To explore the therapeutic effects and mechanism of fluorescent mitoxantrone hydrochloride nanoparticles on giant cell tumor of bone. Methods. The adsorption capacity of nanoparticles to hydroxyapatite (HA), cell adsorption capacity, encapsulation rate, particle size, and potential of the nanoparticles were determined by HPLC and Zetasizer Nano ZS nanomicelle potentiometer. MTT assay was used to determine the toxicity of nanoparticles to cells. The fluorescent intensity of the nanoparticles and their location in the cells were observed under a fluorescence microscope. RT-qPCR and Western blotting were then used to measure the expression levels of miRNA, mRNA, and proteins in cells. Transwell and Annexin V-FITC/PI staining tests were used to study the cell invasion and apoptotic rate, respectively. The dual-luciferase reporter gene experiment was then carried out to verify the binding relationship between miR-125b and its predicted target. Results. ALN-FOL-MTO-NLC nanoparticles showed a stronger adsorption capacity for HA and stronger toxicity to GCTB28 cells. Compared to normal tissues, the expression level of miR-125b in giant bone tumor tissue and cells was significantly downregulated, and the expression level of miR-125b was upregulated to some extent after treatment. Overexpression of miR-125b or treatment of ALN-FOL-MTO-NLC nanoparticles can inhibit the malignant behavior of GCTB28 cells, whereas the inhibition of the expression of miR-125b can promote the malignant behavior of GCTB28 cells. The result showed that parathyroid hormone receptor 1 (PTH1R) was a downstream target gene for miR-125b. Rescue experiment showed that the treatment of GCTB28 with ALN-FOL-MTO-NLC nanoparticles while inhibiting miR-125b expression can reduce the inhibitory effect of miR-125b on the malignant behavior of GCTB28 cells, whereas upregulating the expression levels of miR-125b and PTH1R in GCTB28 cells had no significant effect on the malignant behavior of GCTB28 cells. Conclusion. ALN-FOL-MTO-NLC nanoparticles have a certain inhibitory effect on the malignant behavior of giant cell tumor of bone through the miR-125b/PTH1R molecular axis.


2010 ◽  
Vol 41 (3) ◽  
pp. 212-223 ◽  
Author(s):  
Wouter J. Eijgelaar ◽  
Anton J. G. Horrevoets ◽  
Ann-Pascale J. J. Bijnens ◽  
Mat J. A. P. Daemen ◽  
Wim F. J. Verhaegh

We focus on similarities in the transcriptome of human Kupffer cells and alveolar, splenic, and atherosclerotic plaque-residing macrophages. We hypothesized that these macrophages share a common expression signature. We performed microarray analysis on mRNA from these subsets (4 patients) and developed a novel statistical method to identify genes with significantly similar expression levels. Phenotypic and functional diversity between macrophage subpopulations reflects their plasticity to respond to microenvironmental signals. Apart from detecting differences in expression profiles, the comparison of the transcriptomes of different macrophage populations may also allow the definition of molecular similarities between these subsets. This new method calculates the maximum difference in gene expression level, based on the estimated confidence interval on that gene's expression variance. We listed the genes by equivalence ranking relative to expression level. FDR estimation was used to determine significance. We identified 500 genes with significantly equivalent expression levels in the macrophage subsets at 5.5% FDR using a confidence level of α = 0.05 for equivalence. Among these are the established macrophage marker CD68, IL1 receptor antagonist, and MHC-related CD1C. These 500 genes were submitted to IPA and GO clustering using DAVID. Additionally, hierarchical clustering of these genes in the Novartis human gene expression atlas revealed a subset of 200 genes specifically expressed in macrophages. Equivalently expressed genes, identified by this new method, may not only help to dissect common molecular mechanisms, but also to identify cell- or condition-specific sets of marker genes that can be used for drug targeting and molecular imaging.


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