scholarly journals MiR-26a inhibits the inflammatory response of microglia by targeting HMGA2 in intracerebral hemorrhage

2020 ◽  
Vol 48 (6) ◽  
pp. 030006052092961 ◽  
Author(s):  
Jun Jin ◽  
Feng Zhou ◽  
Jie Zhu ◽  
Weixian Zeng ◽  
Yong Liu

Objective Intracerebral hemorrhage (ICH) is a common cerebrovascular disease with high mortality and poor prognosis. Therefore, the biological function and underlying molecular mechanism of miR-26a in inflammatory injury following ICH was investigated. Methods The potential role of miR-26a was investigated in lipopolysaccharide (LPS)-treated microglial cells by quantitative real-time PCR. To explore the potential role of HMGA2 in the miR-26a-regulated inflammatory response, LPS-induced microglial cells were cotransfected with an miR-26a mimic and pcDNA-HMGA2. Then, lentivirus-mediated overexpression of an miR-26a mimic in mouse microglial cells was performed, and the effects of miR-26a treatment on IL-6, IL-1β, and TNF-α expression in the mouse brain, neurological behavior, and rotarod test performance of mice after ICH were observed. Results MiR-26a was significantly downregulated in LPS-treated microglia and ICH mouse models. MiR-26a markedly reduced IL-6, IL-1β, and TNF-α expression in LPS-treated microglial cells. Furthermore, HMGA2 was verified as a direct target of miR-26a. In vivo, miR-26a overexpression in mouse microglial cells significantly suppressed proinflammatory cytokine expression in mouse brains and markedly improved the neurological behavior and rotarod test performance of mice after ICH. Conclusion MiR-26a remarkably inhibited proinflammatory cytokine release by targeting HMGA2, indicating that miR-26a could protect against secondary brain injury following ICH.

2021 ◽  
Vol 28 (1) ◽  
Author(s):  
Neha Pandey ◽  
Meghana Rastogi ◽  
Sunit K. Singh

Abstract Background Chandipura virus (CHPV) is a negative single-stranded RNA virus of the Rhabdoviridae family. CHPV infection has been reported in Central and Western India. CHPV causes acute encephalitis with a case fatality rate of 70 % and mostly affects children below 15 years of age. CHPV infection in brain leads to neuronal apoptosis and activation of the microglial cells. The microRNAs (miRNAs) are small endogenous non-coding RNA that regulate the gene expression. Viral infections perturb the expression pattern of cellular miRNAs, which may in turn affect the expression pattern of downstream genes. This study aims to investigate hsa-miR-21-5p mediated regulation of PTEN, AKT, NF-ĸBp65, IL-6, TNF-α, and IL-1β, in human microglial cells during CHPV infection. Methods To understand the role of hsa-miR-21-5p in CHPV infection, the human microglial cells were infected with CHPV (MOI-0.1). Real-time PCR, western blotting, Luciferase assay, over-expression and knockdown techniques were used to understand the role of hsa-miR-21-5p in the regulation of PTEN, AKT and, NF-ĸBp65, IL-6, TNF-α, and IL-1β in this study. Results The hsa-miR-21-5p was found to be upregulated during CHPV infection in human microglial cells. This led to the downregulation of PTEN which promoted the phosphorylation of AKT and NF-ĸBp65. Over-expression of hsa-miR-21-5p led to the decreased expression of PTEN and promoted further phosphorylation of AKT and NF-ĸBp65 in human microglial cells. However, the inhibition of hsa-miR-21-5p using hsa-miR-21-5p inhibitor restored the expression. Conclusions This study supports the role of hsa-miR-21-5p in the regulation of pro-inflammatory genes in CHPV infected human microglial cells.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Jianwei Zhang ◽  
Lei Han ◽  
Feng Chen

Abstract Background Let-7a-5p is demonstrated to be a tumor inhibitor in nasopharyngeal carcinoma. However, the role of let-7a-5p in chronic rhinosinusitis with nasal polyps (CRSwNP) has not been reported. This study is designed to determine the pattern of expression and role of let-7a-5p in CRSwNP. Methods The expression level of let-7a-5p, TNF-α, IL-1β, and IL-6 in CRSwNP tissues and cells were detected by RT-qPCR. Western blot assay was carried out to measure the protein expression of the Ras-MAPK pathway. Dual luciferase reporter assay and RNA pull-down assay were used to explore the relationship between let-7a-5p and IL-6. Results Let-7a-5p was significantly downregulated in CRSwNP tissues and cells. Moreover, the mRNA expression of TNF-α, IL-1β and IL-6 was increased in CRSwNP tissues, while let-7a-5p mimic inhibited the expression of TNF-α, IL-1β and IL-6. Besides that, let-7a-5p was negatively correlated with TNF-α, IL-1β and IL-6 in CRSwNP tissues. In our study, IL-6 was found to be a target gene of let-7a-5p. Additionally, let-7-5p mimic obviously reduced the protein levels of Ras, p-Raf1, p-MEK1 and p-ERK1/2, while IL-6 overexpression destroyed the inhibitory effect of let-7a-5p on the Ras-MAPK pathway in CRSwNP. Conclusion We demonstrated that let-7a-5p/IL-6 interaction regulated the inflammatory response through the Ras-MAPK pathway in CRSwNP.


Author(s):  
Meng Li ◽  
Xiaoyang Huang ◽  
Qingcui Zhuo ◽  
Jinghui Zhang ◽  
Xiuli Ju

Neonatal sepsis (NS) occurs in neonates within 28 days, especially preterm infants. The dysregulation of miRNAs is widely detected in NS. The study investigated the expression changes and clinical significance of miR-129-5p in NS patients and further explored the regulatory role of miR-129-5p in the LPS-induced inflammatory response in monocytes. A total of 75 neonates with NS and 84 neonates without NS were recruited. qRT-PCR was used for the measurement of miR-129-5p expression. The receiver operating characteristic (ROC) curve was constructed for diagnostic value analysis. ELISA was used to detect the concentration of inflammatory cytokines. Monocytes were isolated from the blood of neonates to investigate the role of miR-129-5p in the LPS-induced inflammatory response in vitro. miR-129-5p was low expressed in the serum of NS cases compared with controls. Serum miR-129-5p had a diagnostic value for NS with a sensitivity of 82.7% and specificity of 79.8%. There was close association for serum miR-129-5p with TNF-α (r = -0.652, p < 0.001) and IL-8 (r = -0.700, p < 0.001) levels in NS patients. Overexpression of miR-129-5p reversed the increasing trend of TNF-α and IL-8 induced by LPS, whereas miR-129-5p downregulation aggravated the increase of TNF-α and IL-8 induced by LPS in monocytes. MiR-129-5p was downregulated in the serum of NS patients, and it might be a promising biomarker for disease diagnosis. Overexpression of miR-129-5p alleviated the inflammatory response of NS.


2021 ◽  
Author(s):  
Kim Chiok ◽  
Kevin Hutchison ◽  
Lindsay Grace Miller ◽  
Santanu Bose ◽  
Tanya A Miura

Critically ill COVID-19 patients infected with SARS-CoV-2 display signs of generalized hyperinflammation. Macrophages trigger inflammation to eliminate pathogens and repair tissue, but this process can also lead to hyperinflammation and resulting exaggerated disease. The role of macrophages in dysregulated inflammation during SARS-CoV-2 infection is poorly understood. We used SARS-CoV-2 infected and glycosylated soluble SARS-CoV-2 Spike S1 subunit (S1) treated THP-1 human-derived macrophage-like cell line to clarify the role of macrophages in pro-inflammatory responses. Soluble S1 upregulated TNF-α and CXCL10 mRNAs, and induced secretion of TNF-α from THP-1 macrophages. While THP-1 macrophages did not support productive SARS-CoV-2 replication, virus infection resulted in upregulation of both TNF-α and CXCL10 genes. Our study shows that S1 is a key viral component inducing inflammatory response in macrophages, independently of virus replication. Thus, virus-infected or soluble S1-activated macrophages may become sources of pro-inflammatory mediators contributing to hyperinflammation in COVID-19 patients.


2020 ◽  
Vol 40 (6) ◽  
Author(s):  
Xudong Wang ◽  
Yali Wang ◽  
Mingjian Kong ◽  
Jianping Yang

Abstract Background: Septic acute kidney injury is considered as a severe and frequent complication that occurs during sepsis. The present study was performed to understand the role of miR-22-3p and its underlying mechanism in sepsis-induced acute kidney injury. Methods: Rats were injected with adenovirus carrying miR-22-3p or miR-NC in the caudal vein before cecal ligation. Meanwhile, HK-2 cells were transfected with the above adenovirus following LPS stimulation. We measured the markers of renal injury (blood urea nitrogen (BUN), serum creatinine (SCR)). Histological changes in kidney tissues were examined by hematoxylin and eosin (H&E), Masson staining, periodic acid Schiff staining and TUNEL staining. The levels of IL-1β, IL-6, TNF-α and NO were determined by ELISA assay. Using TargetScan prediction and luciferase reporter assay, we predicted and validated the association between PTEN and miR-22-3p. Results: Our data showed that miR-22-3p was significantly down-regulated in a rat model of sepsis-induced acute kidney injury, in vivo and LPS-induced sepsis model in HK-2 cells, in vitro. Overexpression of miR-22-3p remarkably suppressed the inflammatory response and apoptosis via down-regulating HMGB1, p-p65, TLR4 and pro-inflammatory factors (IL-1β, IL-6, TNF-α and NO), both in vivo and in vitro. Moreover, PTEN was identified as a target of miR-22-3p. Furthermore, PTEN knockdown augmented, while overexpression reversed the suppressive role of miR-22-3p in LPS-induced inflammatory response. Conclusions: Our results showed that miR-22-3p induced protective role in sepsis-induced acute kidney injury may rely on the repression of PTEN.


1998 ◽  
Vol 274 (1) ◽  
pp. L26-L31 ◽  
Author(s):  
Paul J. Jagielo ◽  
Timothy J. Quinn ◽  
Nilofer Qureshi ◽  
David A. Schwartz

To further determine the importance of endotoxin in grain dust-induced inflammation of the lower respiratory tract, we evaluated the efficacy of pentaacylated diphosphoryl lipid A derived from the lipopolysaccharide of Rhodobacter sphaeroides (RsDPLA) as a partial agonist of grain dust-induced airway inflammation. RsDPLA is a relatively inactive compound compared with lipid A derived from Escherichia coli (LPS) and has been demonstrated to act as a partial agonist of LPS-induced inflammation. To assess the potential stimulatory effect of RsDPLA in relation to LPS, we incubated THP-1 cells with RsDPLA (0.001–100 μg/ml), LPS (0.02 μg endotoxin activity/ml), or corn dust extract (CDE; 0.02 μg endotoxin activity/ml). Incubation with RsDPLA revealed a tumor necrosis factor (TNF)-α stimulatory effect at 100 μg/ml. In contrast, incubation with LPS or CDE resulted in TNF-α release at 0.02 μg/ml. Pretreatment of THP-1 cells with varying concentrations of RsDPLA before incubation with LPS or CDE (0.02 μg endotoxin activity/ml) resulted in a dose-dependent reduction in the LPS- or CDE-induced release of TNF-α with concentrations of RsDPLA of up to 10 μg/ml but not at 100 μg/ml. To further understand the role of endotoxin in grain dust-induced airway inflammation, we utilized the unique LPS inhibitory property of RsDPLA to determine the inflammatory response to inhaled CDE in mice in the presence of RsDPLA. Ten micrograms of RsDPLA intratracheally did not cause a significant inflammatory response compared with intratracheal saline. However, pretreatment of mice with 10 μg of RsDPLA intratracheally before exposure to CDE (5.4 and 0.2 μg/m3) or LPS (7.2 and 0.28 μg/m3) resulted in significant reductions in the lung lavage concentrations of total cells, neutrophils, and specific proinflammatory cytokines compared with mice pretreated with sterile saline. These results confirm the LPS-inhibitory effect of RsDPLA and support the role of endotoxin as the principal agent in grain dust causing airway inflammation.


2020 ◽  
Vol 78 (6) ◽  
Author(s):  
Xia Luo ◽  
Bo Xu ◽  
Tianqin Xiong ◽  
Yulin Su ◽  
Chang liu ◽  
...  

ABSTRACT Currently, the potential role of the alterations occurring in the liver immune system and intestinal flora in liver injury remains unknown. Our study aimed to explore the impacts of intestinal microbial barrier damage induced by ceftriaxone on liver immunity. We developed the BALB/c mice model by administering ceftriaxone. The intestinal microbial barrier damage was observed by 16S rRNA, and the pathological changes of intestines and livers were detected by H&E or transmission electron microscope. The activation of immunocytes were tested by Flow Cytometry; the expression of LPS, ALT, AST, IL-6 and TNF-α were detected by Limulus Test or ELISA. Compared to the control, the intestinal microbes significantly decreased in ceftriaxone group. Additionally, the weight of cecum contents increased, the intestinal wall became thinner and the villus in the small intestine and cecum were damaged. The expression of LPS and the ratio of liver lymphocytes were significantly increased. H&E results indicated the structures of liver arose the pathologic changes. Meanwhile, the content of serum ALT, AST, IL-6 and TNF-α increased. Collectively, our study indicates that the damages of gut microbial barrier induced by ceftriaxone prompted activation of immunocytes and release of inflammatory cytokines, which may lead to chronic inflammation in liver.


2018 ◽  
Vol 1437 (1) ◽  
pp. 15-21 ◽  
Author(s):  
Rosanna Ramhorst ◽  
Guillermina Calo ◽  
Daniel Paparini ◽  
Daiana Vota ◽  
Vanesa Hauk ◽  
...  

2020 ◽  
Vol 11 (10) ◽  
pp. 9252-9262 ◽  
Author(s):  
Zhigang Zhang ◽  
Changming Guo ◽  
Huijie Jiang ◽  
Bing Han ◽  
Xiaoqiao Wang ◽  
...  

Schematic diagram of the mechanism of post treatment with natural astaxanthin attenuating arsenic-induced inflammatory response in rat liver.


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