scholarly journals Intestinal Epithelial Cell Derived Exosomes Package MicroRNA-23a-3p Alleviate Gut Damage After Ischemia/Reperfusion via Targeting MAP4K4

2021 ◽  
Author(s):  
Jin Yang ◽  
Xinguo Zheng ◽  
Yanling Wu ◽  
Aiping Wang ◽  
Chenhui Wang ◽  
...  
Keyword(s):  
Cell Function ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Bioactive Molecules ◽  
Intestinal Epithelial ◽  
Target Molecule ◽  
Downstream Target ◽  
Gut Damage

Abstract Backgroud: Intestinal epithelial cells (IEC) contribute to regulate gut injury after intestinal isochemia/reperfusion (II/R). Exosomes are well documented to deliver bioactive molecules to recipient cells to modulate cell function. However, the role of IEC-derived exosomes in gut damage after II/R and the underlying mechanisms remains unclear. Methods IEC-derived exosomes were intravenously injected into the rats after the superior mesenteric artery occlusion for 45 min following reperfusion for 6h. The scores of gut injury, ZO-1 and IL-17A expression, TNF-α and endotoxin concentration were determined at 3 days after II/R assault. Exosomal microRNA-23a-3p and its downstream target molecule-MAP4K4 were also detected. Results Our results showed that the IEC-derived exosomes attenuated the damage of IECs after oxygen-glucose deprivation in vitro (p<0.05) and the degree of gut injury at 3 days after II/R assault in vivo (p<0.05). Injection of miR-23a-3p knockdown exosomes derived from IECs aggravated the II/R injury whereas PF-6260933, a small-molecule inhibitor of MAP4K4, was partly reversed the injuried degree by intraperitoneal injection. Underlying mechanism studies revealed that exosomal miR-23a-3p attenuated gut damage by regulating its downstream target MAP4K4. Conclusions We demonstrated that IEC-derived exosomes alleviated the II/R injury and promoted gut damage recovery via exosomal miR-23a-3p and its downstream target molecule-MAP4K4.

scholarly journals N6-methyladenosine demethylase FTO impairs hepatic ischemia–reperfusion injury via inhibiting Drp1-mediated mitochondrial fragmentation

2021 ◽  
Vol 12 (5) ◽  
Author(s):  
Ying Dong Du ◽  
Wen Yuan Guo ◽  
Cong Hui Han ◽  
Ying Wang ◽  
Xiao Song Chen ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Mitochondrial Fragmentation ◽  
Hepatic Ischemia ◽  
Adeno Associated Virus ◽  
Downstream Target ◽  
Hepatic Ischemia Reperfusion

AbstractDespite N6-methyladenosine (m6A) is functionally important in various biological processes, its role and the underlying regulatory mechanism in the liver remain largely unexplored. In the present study, we showed that fat mass and obesity-associated protein (FTO, an m6A demethylase) was involved in mitochondrial function during hepatic ischemia–reperfusion injury (HIRI). We found that the expression of m6A demethylase FTO was decreased during HIRI. In contrast, the level of m6A methylated RNA was enhanced. Adeno-associated virus-mediated liver-specific overexpression of FTO (AAV8-TBG-FTO) ameliorated the HIRI, repressed the elevated level of m6A methylated RNA, and alleviated liver oxidative stress and mitochondrial fragmentation in vivo and in vitro. Moreover, dynamin-related protein 1 (Drp1) was a downstream target of FTO in the progression of HIRI. FTO contributed to the hepatic protective effect via demethylating the mRNA of Drp1 and impairing the Drp1-mediated mitochondrial fragmentation. Collectively, our findings demonstrated the functional importance of FTO-dependent hepatic m6A methylation during HIRI and provided valuable insights into the therapeutic mechanisms of FTO.

scholarly journals LINGO-1 shRNA protects the brain against ischemia/reperfusion injury by inhibiting the activation of NF-κB and JAK2/STAT3

Human Cell ◽  
2021 ◽  
Author(s):  
Jiaying Zhu ◽  
Zhu Zhu ◽  
Yipin Ren ◽  
Yukang Dong ◽  
Yaqi Li ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Nuclear Translocation ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Mice Model ◽  
Down Regulation

AbstractLINGO-1 may be involved in the pathogenesis of cerebral ischemia. However, its biological function and underlying molecular mechanism in cerebral ischemia remain to be further defined. In our study, middle cerebral artery occlusion/reperfusion (MACO/R) mice model and HT22 cell oxygen–glucose deprivation/reperfusion (OGD/R) were established to simulate the pathological process of cerebral ischemia in vivo and in vitro and to detect the relevant mechanism. We found that LINGO-1 mRNA and protein were upregulated in mice and cell models. Down-regulation LINGO-1 improved the neurological symptoms and reduced pathological changes and the infarct size of the mice after MACO/R. In addition, LINGO-1 interference alleviated apoptosis and promoted cell proliferation in HT22 of OGD/R. Moreover, down-regulation of LINGO-1 proved to inhibit nuclear translocation of p-NF-κB and reduce the expression level of p-JAK2 and p-STAT3. In conclusion, our data suggest that shLINGO-1 attenuated ischemic injury by negatively regulating NF-KB and JAK2/STAT3 pathways, highlighting a novel therapeutic target for ischemic stroke.

scholarly journals Hippo-YAP/MCP-1 mediated tubular maladaptive repair promote inflammation in renal failed recovery after ischemic AKI

2021 ◽  
Vol 12 (8) ◽  
Author(s):  
Zhihuang Zheng ◽  
Chuanlei Li ◽  
Guangze Shao ◽  
Jinqing Li ◽  
Kexin Xu ◽  
...  
Keyword(s):  
Chronic Inflammation ◽  
Ischemia Reperfusion ◽  
Hippo Pathway ◽  
Glucose Deprivation ◽  
Macrophage Infiltration ◽  
Renal Inflammation ◽  
Monocyte Chemoattractant Protein 1 ◽  
The Hippo Pathway

AbstractAcute kidney injury (AKI) is associated with significant morbidity and its chronic inflammation contributes to subsequent chronic kidney disease (CKD) development. Yes-associated protein (YAP), the major transcriptional coactivator of the Hippo pathway, has been shown associated with chronic inflammation, but its role and mechanism in AKI-CKD transition remain unclear. Here we aimed to investigate the role of YAP in AKI-induced chronic inflammation. Renal ischemia/reperfusion (I/R) was used to induce a mouse model of AKI-CKD transition. We used verteporfin (VP), a pharmacological inhibitor of YAP, to treat post-IRI mice for a period, and evaluated the influence of YAP inhibition on long-term outcomes of AKI. In our results, severe IRI led to maladaptive tubular repair, macrophages infiltration, and progressive fibrosis. Following AKI, the Hippo pathway was found significantly altered with YAP persistent activation. Besides, tubular YAP activation was associated with the maladaptive repair, also correlated with interstitial macrophage infiltration. Monocyte chemoattractant protein 1 (MCP-1) was found notably upregulated with YAP activation. Of note, pharmacological inhibition of YAP in vivo attenuated renal inflammation, including macrophage infiltration and MCP-1 overexpression. Consistently, in vitro oxygen-glucose deprivation and reoxygenation (OGD/R) induced YAP activation and MCP-1 overproduction whereas these could be inhibited by VP. In addition, we modulated YAP activity by RNA interference, which further confirmed YAP activation enhances MCP-1 expression. Together, we concluded tubular YAP activation with maladaptive repair exacerbates renal inflammation probably via promoting MCP-1 production, which contributes to AKI-CKD transition.

scholarly journals miR-19a/b-3p promotes inflammation during cerebral ischemia/reperfusion injury via SIRT1/FoxO3/SPHK1 pathway

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Feng Zhou ◽  
Yu-Kai Wang ◽  
Cheng-Guo Zhang ◽  
Bing-Yi Wu
Keyword(s):  
Inflammatory Responses ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Artery Occlusion ◽  
Luciferase Assay ◽  
In Vivo Model ◽  
Tunel Staining

Abstract Background Stroke affects 3–4% of adults and kills numerous people each year. Recovering blood flow with minimal reperfusion-induced injury is crucial. However, the mechanisms underlying reperfusion-induced injury, particularly inflammation, are not well understood. Here, we investigated the function of miR-19a/b-3p/SIRT1/FoxO3/SPHK1 axis in ischemia/reperfusion (I/R). Methods MCAO (middle cerebral artery occlusion) reperfusion rat model was used as the in vivo model of I/R. Cultured neuronal cells subjected to OGD/R (oxygen glucose deprivation/reperfusion) were used as the in vitro model of I/R. MTT assay was used to assess cell viability and TUNEL staining was used to measure cell apoptosis. H&E staining was employed to examine cell morphology. qRT-PCR and western blot were performed to determine levels of miR-19a/b-3p, SIRT1, FoxO3, SPHK1, NF-κB p65, and cytokines like TNF-α, IL-6, and IL-1β. EMSA and ChIP were performed to validate the interaction of FoxO3 with SPHK1 promoter. Dual luciferase assay and RIP were used to verify the binding of miR-19a/b-3p with SIRT1 mRNA. Results miR-19a/b-3p, FoxO3, SPHK1, NF-κB p65, and cytokines were elevated while SIRT1 was reduced in brain tissues following MCAO/reperfusion or in cells upon OGD/R. Knockdown of SPHK1 or FoxO3 suppressed I/R-induced inflammation and cell death. Furthermore, knockdown of FoxO3 reversed the effects of SIRT1 knockdown. Inhibition of the miR-19a/b-3p suppressed inflammation and this suppression was blocked by SIRT1 knockdown. FoxO3 bound SPHK1 promoter and activated its transcription. miR-19a/b-3p directly targeted SIRT1 mRNA. Conclusion miR-19a/b-3p promotes inflammatory responses during I/R via targeting SIRT1/FoxO3/SPHK1 axis.

scholarly journals VX765, a Specific Caspase-1 Inhibitor, Alleviates Lung Ischemia Reperfusion Injury by Suppressing Endothelial Pyroptosis and Barrier Dysfunction

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Siyi Wu ◽  
Zhao Li ◽  
Mengling Ye ◽  
Chunxia Liu ◽  
Hao Liu ◽  
...  
Keyword(s):  
Protective Effect ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
High Morbidity ◽  
Barrier Dysfunction ◽  
Caspase 1

Lung ischemia reperfusion injury (LIRI) is a complex pathophysiological process with high morbidity and mortality. An important pathophysiological characteristic of LIRI is endothelial barrier dysfunction, although the mechanism involved in this process remains unclear. VX765, a specific caspase-1 inhibitor, has been shown to have a protective effect against several diseases including sepsis, atherosclerosis, and glial inflammatory disease. The objective of this study was to determine whether VX765 had a protective effect in LIRI. The results showed that lung ischemia/reperfusion (I/R) and oxygen/glucose deprivation and reoxygenation (OGD/R) induced endothelial pyroptosis and barrier dysfunction characterized by an inflammatory response. Treatment with VX765 successfully alleviated I/R- and OGD/R-induced endothelial pyroptosis and barrier dysfunction by inhibiting caspase-1 in vivo and in vitro. In conclusion, these findings showed that VX765 provided effective protection against lung I/R-induced endothelial pyroptosis and barrier dysfunction.

scholarly journals Xingnaojing Injection Protects against Cerebral Ischemia Reperfusion Injury via PI3K/Akt-Mediated eNOS Phosphorylation

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Yue-Ming Zhang ◽  
Xiao-Yu Qu ◽  
Jing-Hui Zhai ◽  
Li-Na Tao ◽  
Huan Gao ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Underlying Mechanism ◽  
Dapi Staining ◽  
Pi3k Inhibitor Ly294002 ◽  
Cerebral Ischemic

Xingnaojing (XNJ) injection, derived from traditional Chinese medicine formulation, has a protective effect against stroke, but the underlying mechanism is unclear, which severely limited its clinical application. This research aims to elucidate the role and mechanism of XNJ in reducing cerebral ischemic reperfusion (I/R) injury. Rats received 2 h cerebral ischemia followed by reperfusion of 24 h and were intraperitoneally given 5, 10, or 15 ml/kg XNJ 24 h before ischemia and at the onset of reperfusion, respectively. TTC staining, HE staining, and neurological score were implied to evaluate the effectiveness of XNJ. The protein expressions of PI3K/Akt and eNOS signaling were measured. Experiments were further performed in human brain microvascular endothelial cells (HBMECs) to investigate the protective mechanisms of XNJ. HBMECs were subjected to 3 h oxygen and glucose deprivation following 24 h of reoxygenation (OGD) to mimic cerebral I/R in vitro. PI3K inhibitor LY294002 was added with or without the preconditioning of XNJ. Multiple methods including western blot, immunofluorescence, DAPI staining, JC-1, and flow cytometry were carried out to evaluate the effect of XNJ on HBMECs. XNJ could improve rat cerebral ischemic injury and OGD induced HBMECs apoptosis. In vivo and in vitro researches indicated that the mechanism might be relevant to the activation of PI3K/Akt/eNOS signaling.

scholarly journals Schizandrin Protects against OGD/R-Induced Neuronal Injury by Suppressing Autophagy: Involvement of the AMPK/mTOR Pathway

Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3624 ◽  
Author(s):  
Guangyun Wang ◽  
Tiezheng Wang ◽  
Yuanyuan Zhang ◽  
Fang Li ◽  
Boyang Yu ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Pc12 Cells ◽  
Cell Damage ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Mtor Pathway ◽  
Protective Effects ◽  
Compound C

The neuroprotective role of schizandrin (SA) in cerebral ischemia-reperfusion (I/R) was recently highlighted. However, whether SA plays a regulatory role on autophagy in cerebral I/R injury is still unclear. This study aimed to explore whether the neuroprotective mechanisms of SA were linked to its regulation of AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/autophagy pathway in vivo and in vitro. The present study confirmed that SA significantly improved oxygen-glucose deprivation/re-oxygenation (OGD/R)-induced PC12 cells injury. The results of immunoblotting and confocal microscope showed that SA decreased autophagy in OGD/R-injured PC12 cells, which was reflected by the decreased Beclin-1 and LC3-II expression, autophagy flux level, and LC3 puncta formation. In addition, the autophagy inducer rapamycin partially prevented the effects of SA on cell viability and autophagy after OGD/R, whereas the autophagy inhibitor 3-methyladenine (3-MA) exerted the opposite effect. The results of Western blotting showed that SA markedly decreased the phosphorylation of AMPK (p-AMPK), whereas the phosphor-mTOR (p-mTOR) levels increased in the presence of OGD/R insult. Furthermore, pretreatment with the AMPK inducer AICAR partially reversed the protective effects and autophagy inhibition of SA. However, AMPK inhibitor Compound C pretreatment further promoted the inhibition of SA on autophagy induction and cell damage induced by OGD/R. Taken together, these findings demonstrate that SA protects against OGD/R insult by inhibiting autophagy through the regulation of the AMPK-mTOR pathway and that SA may have therapeutic value for protecting neurons from cerebral ischemia.

scholarly journals Mucin degrader Akkermansia muciniphila accelerates intestinal epithelial regeneration and repairs damaged intestinal mucosa

2020 ◽  
Author(s):  
Mi-Na Kweon ◽  
Seungil Kim ◽  
Tae-Young Kim ◽  
Yeji Kim ◽  
Yong-Soo Lee ◽  
...  
Keyword(s):  
Intestinal Epithelial ◽  
Akkermansia Muciniphila ◽  
Epithelial Regeneration ◽  
Epithelial Development ◽  
Degrading Bacteria ◽  
Pre Treatment ◽  
Gut Damage ◽  
G Protein Coupled

Abstract Background: Mucin-degrading bacteria are densely populated in the intestinal epithelium; however, their interaction with intestinal stem cells (ISCs) and their progeny has not been elucidated. To determine whether mucin-degrading bacteria play a role in gut homeostasis, mice were treated with Akkermansia muciniphila, a specialized species that degrades mucin. A total of 32 fecal samples were obtained from healthy volunteers and A. muciniphila was isolated from 11 samples. Mechanism of A. muciniphila was observed in vivo and in vitro, and studied using organoids, histology, metagenomics, and whole genome sequencing.Results: We found that administration of A. muciniphila for 4 weeks accelerated theproliferation of Lgr5+ ISCs and promoted the differentiation of Paneth cells and goblet cells in the small intestine (SI). The levels of acetic and propionic acids were higher in the cecal contents of A. muciniphila-treated mice than in PBS-treated mice. SI organoids treated with cecal content supernatant obtained from A. muciniphila-treated mice were larger and could be diminished by treatment with G protein-coupled receptor (Gpr)41/43 antagonists. Pre- treatment of mice with A. muciniphila reduced gut damage caused by radiation and methotrexate. A novel isotype of A. muciniphila strain was isolated from heathy human feces that possessed improved functions for intestinal epithelial regeneration.Conclusions: These findings suggest that mucin-degrading bacteria (such as A. muciniphila)may play a crucial role in promoting ISC-mediated epithelial development and contribute to intestinal homeostasis maintenance.

scholarly journals Microglia-derived FGF21 as a modulator of astrocytic phenotype and cerebral ischemia injury

2020 ◽  
Author(s):  
Fei Liu ◽  
Dongxue Wang ◽  
Liyun Zhu ◽  
Jingting Du ◽  
Ping Lin ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Cell Counting ◽  
Fibroblast Growth Factor 21 ◽  
Protective Effects ◽  
Triphenyltetrazolium Chloride

Abstract Background: Fibroblast growth factor 21 (FGF21) is an important neuroprotective factor in the central nervous system (CNS), and it has been reported that FGF21 can protect against cerebral ischemia during the acute phase. However, the possible effects of FGF21 on ischemic brains and the interactions between FGF21 and nonneuronal cells have not been examined. Thus, the aim of this study was to elucidate the protective effects of endogenous FGF21 in ischemic brains.Methods: In this study, in vivo ischemia/reperfusion injury mouse model established by transient middle cerebral artery occlusion (MCAO)/reperfusion and in vitro cell models of oxygen/glucose deprivation (OGD)/reoxygenation (R) were used. Western blot analysis, RT-PCR, double immunofluorescence staining, immunohistochemistry, 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin-eosin (H&E) staining, neurobehavioral tests, cell counting kit-8 (CCK-8) assay and high-throughput gene sequencing were employed to explore the mechanism by which FGF21 unleash neuroprotective effort of astrocyte phenotype shifts in ischemic stroke.Results: We found that cortical FGF21 expression significantly increased after MCAO/reperfusion, peaking at 7 d. Ischemia-activated microglia were the main sources of endogenous FGF21 in brain tissue. However, FGF21 deficiency aggravated brain injury and slowed neurological functional recovery in FGF21 knockout mice. The in vitro and vivo studies revealed that FGF21 could activate astrocytes and mediate astrocytic phenotype. FGF21-activated astrocytes contributed to neuronal survival and synaptic protein upregulation after ischemia.Conclusion: Collectively, our data indicate that FGF21 plays vital roles in alleviating ischemic brain by mediating the manifestation of potentially pro-recovery astrocytic phenotypes. Therefore, modulation of FGF21 is a potential target strategy for stroke.

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