scholarly journals TREM-2-p38 MAPK signaling regulates neuroinflammation during chronic cerebral hypoperfusion combined with diabetes mellitus

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Jiawei Zhang ◽  
Yu Liu ◽  
Yaling Zheng ◽  
Yan Luo ◽  
Yu Du ◽  
...  

Abstract Background Diabetes mellitus (DM) and chronic cerebral hypoperfusion(CCH)are both risk factors for cognitive impairment. However, whether DM and CCH can synergistically promote cognitive impairment and the related pathological mechanisms remain unknown. Methods To investigate the effect of DM and CCH on cognitive function, rats fed with high-fat diet (HFD) and injected with low-dose streptozotocin (STZ) followed by bilateral common carotid artery occlusion (BCCAO) were induced to mimic DM and CCH in vivo and mouse BV2 microglial cells were exposed to hypoxia and/or high glucose to mimic CCH complicated with DM pathologies in vitro. To further explore the underlying mechanism, TREM-2-specific small interfering RNA and TREM-2 overexpression lentivirus were used to knock out and overexpress TREM-2, respectively. Results Cognitive deficits, neuronal cell death, neuroinflammation with microglial activation, and TREM-2-MAPK signaling were enhanced when DM was superimposed on CCH both in vivo and in vitro. Manipulating TREM-2 expression levels markedly regulated the p38 MAPK signaling and the inflammatory response in vitro. TREM-2 knockout intensified while TREM-2 overexpression suppressed the p38 MAPK signaling and subsequent pro-inflammatory mediator production under high glucose and hypoxia condition. Conclusions These results suggest that TREM-2 negatively regulates p38 MAPK-mediated inflammatory response when DM was synergistically superimposed on CCH and highlight the importance of TREM-2 as a potential target of immune regulation in DM and CCH.

2020 ◽  
Author(s):  
Yaling Zheng ◽  
Jiawei Zhang ◽  
Yao Zhao ◽  
Yaxuan Zhang ◽  
Xiaojie Zhang ◽  
...  

Abstract BackgroundChronic cerebral hypoperfusion (CCH) is regarded as a high-risk factor for cognitive decline in vascular dementia (VaD). We have previously shown that diabetes mellitus (DM) synergistically promotes CCH-induced cognitive dysfunction via exacerbating neuroinflammation. Furthermore, curcumin has been shown to exhibit anti-inflammatory and neuroprotective activities. However, the effects of curcumin on CCH-induced cognitive impairments in DM have remained unknown.MethodsRats were fed with a high-fat diet (HFD) and injected with low-dose streptozotocin (STZ), followed by bilateral common carotid artery occlusion (BCCAO), to model DM and CCH in vivo. After BCCAO, curcumin (50 mg/kg) was administered intraperitoneally every two days for eight weeks to evaluate its therapeutic effects. Additionally, mouse BV2 microglial cells were exposed to hypoxia and high glucose to model CCH and DM pathologies in vitro. ResultsCurcumin treatment significantly improved DM/CCH-induced cognitive deficits and attenuated neuronal cell death. Molecular analysis revealed that curcumin exerted protective effects via suppressing neuroinflammation induced by microglial activation, regulating the triggering receptor expressed on myeloid cells 2 (TREM2)/toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) pathway, alleviating apoptosis, and reducing nod-like receptor protein 3 (NLRP3)-dependent pyroptosis.ConclusionsTaken together, our findings suggest that curcumin represents a promising therapy for DM/CCH-induced cognitive impairments.


2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Bin Leng ◽  
Cong Li ◽  
Yang Sun ◽  
Kun Zhao ◽  
Ling Zhang ◽  
...  

Vascular endothelial dysfunction is associated with increased mortality in patients with diabetes. Astragaloside IV (As-IV) is a bioactive saponin with therapeutic potential as an anti-inflammatory and antiendothelial dysfunction. However, the underlying mechanism for how As-IV ameliorated endothelial dysfunction is still unclear. Therefore, in this study, we examined the protective effect of As-IV against endothelial dysfunction and explored potential molecular biology mechanism. In vivo, rats were intraperitoneally injected with streptozotocin (STZ) at a dose of 65 mg/kg body weight to establish a diabetic model. In vitro studies, rat aortic endothelial cells (RAOEC) were pretreated with As-IV, SB203580 (p38 MAPK inhibitor) for 2 h prior to the addition of high glucose (33 mM glucose). Our findings indicated that As-IV improved impaired endothelium-dependent relaxation and increased the levels of endothelial NO synthase (eNOS) and nitric oxide (NO) both in vivo and in vitro. Besides, As-IV treatment inhibited the elevated inflammation and oxidative stress in diabetic model both in vivo and in vitro. Moreover, As-IV administration reversed the upregulated expression of P2X7R and p-p38 MAPK in vivo and in vitro. Additionally, the effects of both P2X7R siRNA and SB203580 on endothelial cells were similar to As-IV. Collectively, our study demonstrated that As-IV rescued endothelial dysfunction induced by high glucose via inhibition of P2X7R dependent p38 MAPK signaling pathway. This provides a theoretical basis for the further study of the vascular endothelial protective effects of As-IV.


2021 ◽  
Vol 12 ◽  
Author(s):  
Grazia Maugeri ◽  
Claudio Bucolo ◽  
Filippo Drago ◽  
Settimio Rossi ◽  
Michelino Di Rosa ◽  
...  

This study aimed to investigate the high glucose damage on human retinal pigment epithelial (RPE) cells, the role of p38 MAPK signaling pathway and how dimethyl fumarate can regulate that. We carried out in vitro studies on ARPE-19 cells exposed to physiological and high glucose (HG) conditions, to evaluate the effects of DMF on cell viability, apoptosis, and expression of inflammatory and angiogenic biomarkers such as COX-2, iNOS, IL-1β, and VEGF. Our data have demonstrated that DMF treatment attenuated HG-induced apoptosis, as confirmed by reduction of BAX/Bcl-2 ratio. Furthermore, in RPE cells exposed to HG we observed a significant increase of iNOS, COX-2, and IL-1β expression, that was reverted by DMF treatment. Moreover, DMF reduced the VEGF levels elicited by HG, inhibiting p38 MAPK signaling pathway. The present study demonstrated that DMF provides a remarkable protection against high glucose-induced damage in RPE cells through p38 MAPK inhibition and the subsequent down-regulation of VEGF levels, suggesting that DMF is a small molecule that represents a good candidate for diabetic retinopathy treatment and warrants further in vivo and clinical evaluation.


2021 ◽  
Vol 12 ◽  
Author(s):  
Wenxian Li ◽  
Di Wei ◽  
Zheng Zhu ◽  
Xiaomei Xie ◽  
Shuqin Zhan ◽  
...  

Chronic cerebral hypoperfusion (CCH) contributes to cognitive impairments, and hippocampal neuronal death is one of the key factors involved in this process. Dl-3-n-butylphthalide (D3NB) is a synthetic compound originally isolated from the seeds of Apium graveolens, which exhibits neuroprotective effects against some neurological diseases. However, the protective mechanisms of D3NB in a CCH model mimicking vascular cognitive impairment remains to be explored. We induced CCH in rats by a bilateral common carotid artery occlusion (BCCAO) operation. Animals were randomly divided into a sham-operated group, CCH 4-week group, CCH 8-week group, and the corresponding D3NB-treatment groups. Cultured primary hippocampal neurons were exposed to oxygen-glucose deprivation/reperfusion (OGD/R) to mimic CCH in vitro. We aimed to explore the effects of D3NB treatment on hippocampal neuronal death after CCH as well as its underlying molecular mechanism. We observed memory impairment and increased hippocampal neuronal apoptosis in the CCH groups, combined with inhibition of CNTF/CNTFRα/JAK2/STAT3 signaling, as compared with that of sham control rats. D3NB significantly attenuated cognitive impairment in CCH rats and decreased hippocampal neuronal apoptosis after BCCAO in vivo or OGD/R in vitro. More importantly, D3NB reversed the inhibition of CNTF/CNTFRα expression and activated the JAK2/STAT3 pathway. Additionally, JAK2/STAT3 pathway inhibitor AG490 counteracted the protective effects of D3NB in vitro. Our results suggest that D3NB could improve cognitive function after CCH and that this neuroprotective effect may be associated with reduced hippocampal neuronal apoptosis via modulation of CNTF/CNTFRα/JAK2/STAT3 signaling pathways. D3NB may be a promising therapeutic strategy for vascular cognitive impairment induced by CCH.


2021 ◽  
Vol 12 ◽  
Author(s):  
Dan He ◽  
Qiang Li ◽  
Guangli Du ◽  
Guofeng Meng ◽  
Jijia Sun ◽  
...  

Background: Guizhi has the pharmacological activity of anti-inflammatory. However, the effect mechanism of Guizhi against nephrotic syndrome (NS) remains unclear. A network pharmacological approach with experimental verification in vitro and in vivo was performed to investigate the potential mechanisms of Guizhi to treat NS.Methods: Active compounds and potential targets of Guizhi, as well as the related targets of NS were obtained from the public databases. The intersecting targets of Guizhi and NS were obtained through Venny 2.1.0. The key targets and signaling pathways were determined by protein-protein interaction (PPI), genes ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analysis. And the overall network was constructed with Cytoscape. Molecular docking verification was carried out by AutoDock Vina. Finally, in vitro and in vivo experiments were performed to verify the mechanism of Guizhi to treat NS.Results: 63 intersecting targets were obtained, and the top five key targets mainly involed in NF- Kappa B and MAPK signaling pathway. In the overall network, cinnamaldehyde (CA) was the top one active compound with the highest degree value. The molecular docking showed that the top five key targets were of good binding activity with the active components of Guizhi. To in vitro experiment, CA, the main active component of Guizhi, inhibited the secretion of IL-1β, IL-6, TNF-α in LPS challenged RAW264.7 cells, and down regulated the protein expression of p-NF-κB p65 and p-p38 MAPK in LPS challenged RAW264.7 cells. In vitro experiment showed that, 24 urinary protein and renal function were increased in ADR group. To western blot, CA down regulated the protein expression of p-p38 MAPK in rats of adriamycin-induced nephropathy.Conclusion: CA might be the main active component of Guizhi to treat NS, and the underlying mechanism might mainly be achieved by inhibiting MAPK signaling pathway.


2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Rongze Wang ◽  
Yuanxu Zhang ◽  
Fujun Jin ◽  
Gongchen Li ◽  
Yao Sun ◽  
...  

Abstract Type 1 diabetes mellitus (T1DM) is an autoimmune insulin-dependent disease associated with destructive bone homeostasis. Accumulating evidence has proven that miRNAs are widely involved in the regulation of bone homeostasis. However, whether miRNAs also regulate osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in T1DM mice is under exploration. In this study, miRNA microarray was utilized to screen the differentially expressed miRNAs, which uncovered that miR-214-3p potentially inhibited BMSCs osteogenic differentiation in T1DM mice. We found that high glucose suppressed BMSCs osteogenic differentiation with significant elevation of the miR-214-3p expression. Further study found that the osteogenic differentiation of BMSCs was inhibited by AgomiR-214-3p while enhanced by AntagomiR-214-3p in BMSCs supplemented with high glucose. Moreover, we found that miR-214-3p knockout T1DM mice were resistant to high-glucose-induced bone loss. These results provide a novel insight into an inhibitory role of high-glucose-induced miR-214-3p in BMSCs osteogenic differentiation both in vitro and in vivo. Molecular studies revealed that miR-214-3p inhibits BMSCs osteogenic differentiation by targeting the 3′-UTR of β-catenin, which was further corroborated in human bone specimens and BMSCs of T1DM patients. Taken together, our study discovered that miR-214-3p is a pivotal regulator of BMSCs osteogenic differentiation in T1DM mice. Our findings also suggest that miR-214-3p could be a potential target in the treatment of bone disorders in patients with T1DM.


2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Feng He ◽  
Zonghui Xiao ◽  
Hailan Yao ◽  
Sen Li ◽  
Miao Feng ◽  
...  

Abstract Background The P38 mitogen-activated protein kinase (MAPK) pathway plays an essential role in CVB3-induced diseases. We previously demonstrated microRNA-21 has potential inhibitory effect on the MAP2K3 which locates upstream of P38 MAPK and was upregulated in mouse hearts upon CVB3 infection. However, the effect and underlying mechanism of miRNA-21 on CVB3 infection remain unclear. Methods We detected continuous changes of cellular miRNA-21 and P38 MAPK proteins expression profiling post CVB3 infection in vitro within 12 h. P38 MAPK signaling was inhibited by the specific inhibitor, small interfering RNA and miRNA-21 mimic in vitro, CVB3 replication, cell apoptosis rate and proliferation were detected. Viral load in the mice heart, cardiomyocyte apoptosis rate and histological of the heart were also detected in the mice model of viral myocarditis pretreated with miRNA-21-lentivirus. Results We observed significant upregulation of miRNA-21 expression followed by suppression of the MAP2K3/P38 MAPK signaling in CVB3-infected Hela cells. The inactivation of the MAP2K3/P38 MAPK signaling by P38 MAPK specific inhibitor, small interfering RNA against MAP2K3, or miRNA-21 overexpression significantly inhibited viral progeny release from CVB3-infected cells. Mechanistically, when compared with control miRNA, miRNA-21 showed no effect on capsid protein VP1 expression and viral load within host cells, while significantly reversing CVB3-induced caspase-3 activation and cell apoptosis rate, further promoting proliferation of infected cells, which indicates the inhibitory effect of miRNA-21 on CVB3 progeny release. In the in vivo study, when compared with control miRNA, miRNA-21 pretreatment remarkably inactivated the MAP2K3/P38 MAPK signaling in mice and protected them against CVB3 infection as evidenced by significantly alleviated cell apoptosis rate, reduced viral titers, necrosis in the heart as well as by remarkably prolonged survival time. Conclusions miRNA-21 were reverse correlated with P38 MAPK activation post CVB3 infection, miRNA-21 overexpression significantly inhibited viral progeny release and decreased myocytes apoptosis rate in vitro and in vivo, suggesting that miRNA-21 may serve as a potential therapeutic agent against CVB3 infection through targeting the MAP2K3/P38 MAPK signaling.


2017 ◽  
Vol 46 (29) ◽  
pp. 9481-9490 ◽  
Author(s):  
Zhao Zhang ◽  
Hua-Hua Wang ◽  
Hua-Jun Yu ◽  
Yu-Zhen Xiong ◽  
Hai-Tao Zhang ◽  
...  

A gallium(iii) tris(ethoxycarbonyl)corrole is a highly effective photosensitizer against A549 cancer cells via p38 MAPK signaling cascade pathways.


2021 ◽  
Vol 4 (2) ◽  
pp. 1-13
Author(s):  
Kesevan Rajah Kumaran ◽  
Habibah Abdul Wahab ◽  
Zurina Hassan

Vascular dementia (VaD), is one of the most common types of dementia in the ageing population, initiated by chronic cerebral hypoperfusion (CCH). At present, effective therapeutic approaches to cure VaD are still missing. Cholinergic system dysfunction in the central nervous system (CNS) has been recognised as one of the main reasons for learning and memory impairment in VaD patients. Therefore, medications that restore the level of acetylcholine (ACh) neurotransmitter by inhibiting cholinesterase activity were proposed as a potential candidate to treat VaD patients. Permanent occlusion of bilateral common carotid arteries (POBCCA) surgery method was performed to develop CCH model in rats. The present study evaluated the anti-cholinesterase activity of three Malaysian plant methanol leaf extracts in vitro and further validated its cognitive-enhancing effects in vivo using POBCCA rats. The selected plant extracts were Coccoloba uvifera (stems), Mimusops elengi (leaves) and Syzygium aqueum (leaves). The in vitro anti-cholinesterase activities of these plants were determined using Ellman's method. The effects of selected plant extracts (100 and 200 mg/kg, p.o.) on learning and memory functions were evaluated using a series of behavioural tests. All the selected plant extracts exhibited good anti-acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities in vitro, with IC50 ranging from 3.67 to 16.04 and 5.6 to 13.95 µg/mL, respectively. Extracts of S. aqueum (200 mg/kg) improve both short- and long-term recognition memories, whereas M. elengi and S. aqueum (200 mg/kg) extracts improve spatial learning. None of the extracts impaired motor and exploratory functions in POBCCA rats. In conclusion, methanol extracts of C. uvifera, M. elengi and S. aqueum showed good anti-cholinesterase activity in vitro. However, only M. elengi and S. aqueum improve learning and memory function in POBCCA rats.


MAP Kinase ◽  
2016 ◽  
Vol 4 (1) ◽  
Author(s):  
Li Xing

The trigger and etiology of chronic inflammatory diseases are not well understood, hindering the development of efficient therapeutic approaches. The observation that abnormal activity of the p38 MAPK is common to all inflammatory diseases raised the expectation that p38 inhibitors would serve as general anti-inflammatory therapeutics. A large number of inhibitors were consequently discovered. Several compounds of different scaffolds, blocking the p38 MAPK signaling pathway, have entered phase II clinical trials for rheumatoid arthritis, chronic obstructive pulmonary disease, pain, cardiovascular diseases, and cancer. As I review here, in almost all cases the clinical trials have failed, leading to re-design of compounds and re-evaluation of p38 as a suitable target. I describe how structural features, unique to p38<span>α</span>, have been employed in the inhibitor design and achieved high degree of kinome selectivity. I then focus on some of the drugs that reached human trials and summarize their <em>in vitro/in vivo</em> pharmacological profiles and the related outcomes from clinical investigations. These compounds include VX-745, VX-702, RO-4402257, SCIO- 469, BIRB-796, SD-0006, PH-797804, AMG-548, LY2228820, SB-681323 and GW-856553. Finally, I discuss novel suggested approaches for the use of p38 inhibitors such as combining p38 inhibition with inhibiting other targets that function in parallel inflammatory pathways for achieving efficacy in treating inflammatory diseases.


Sign in / Sign up

Export Citation Format

Share Document