scholarly journals MiR-301a Mediates the Effect of IL-6 on the AKT/GSK Pathway and Hepatic Glycogenesis by Regulating PTEN Expression

2015 ◽  
Vol 35 (4) ◽  
pp. 1413-1424 ◽  
Author(s):  
Lin Dou ◽  
Shuyue Wang ◽  
Xiaofang Sui ◽  
Xiangyu Meng ◽  
Tao Shen ◽  
...  

Background/Aims: IL-6 has been implicated in the pathogenesis of insulin resistance. MiR-301a plays an important role in various biological and pathological processes, including cellular development and differentiation, inflammation, apoptosis and cancer. However, whether miR-301a mediates IL-6-induced insulin resistance in hepatocytes remains unknown. Methods: The activation of AKT/GSK pathway and the level of glycogenesis were examed in NCTC 1469 cells transfected miR-301a mimics and inhibitor. Using computational miRNA target prediction database, PTEN was a target of miR-301a. The effect of miR-301a on PTEN expression was evaluated using Luciferase assay and western blot. A PTEN-specific siRNA was used to further determine the effect of PTEN on IL-6-induced insulin resistance. Results: In vivo and in vitro treatment with IL-6 was led to down-regulation of miR-301a, accompanied by impairment of theAKT/GSK pathway and glycogenesis. Importantly, over-expression of miR-301a rescued IL-6-induced decreased activation of the AKT/GSK pathway and hepatic glycogenesis. In contrast, down-regulation of miR-301a induced impaired phosphorylation of AKT and GSK, accompanied by reduced glycogenesis in hepatocytes. Moreover, our results indicate that suppression of PTEN, a target of miR-301a, diminished the effect of IL-6 on the AKT/GSK pathway and hepatic glycogenesis. Conclusion: We present novel evidence of the contribution of miR-301a to IL-6-induced insulin resistance by direct regulation of PTEN expression.

Author(s):  
Xiaoyan Wu ◽  
Wenhui Dong ◽  
Ming Kong ◽  
Haozhen Ren ◽  
Jinglin Wang ◽  
...  

Liver fibrosis is mediated by myofibroblasts, a specialized cell type involved in wound healing and extracellular matrix production. Hepatic stellate cells (HSC) are the major source of myofibroblasts in the fibrotic livers. In the present study we investigated the involvement of CXXC-type zinc-finger protein 5 (CXXC5) in HSC activation and the underlying mechanism. Down-regulation of CXXC5 was observed in activated HSCs compared to quiescent HSCs both in vivo and in vitro. In accordance, over-expression of CXXC5 suppressed HSC activation. RNA-seq analysis revealed that CXXC5 influenced multiple signaling pathways to regulate HSC activation. The proto-oncogene MYCL1 was identified as a novel target for CXXC5. CXXC5 bound to the proximal MYCL1 promoter to repress MYCL1 transcription in quiescent HSCs. Loss of CXXC5 expression during HSC activation led to the removal of CpG methylation and acquisition of acetylated histone H3K9/H3K27 on the MYCL1 promoter resulting in MYCL1 trans-activation. Finally, MYCL1 knockdown attenuated HSC activation whereas MYCL1 over-expression partially relieved the blockade of HSC activation by CXXC5. In conclusion, our data unveil a novel transcriptional mechanism contributing to HSC activation and liver fibrosis.


2018 ◽  
Vol 47 (1) ◽  
pp. 245-256 ◽  
Author(s):  
Fengming Yang ◽  
Ke Wei ◽  
Zhiqiang Qin ◽  
Weitao Liu ◽  
Chuchu Shao ◽  
...  

Background/Aims: MicroRNAs regulate a wide range of biological processes of non-small cell lung cancer (NSCLC). Although miR-598 has been reported to act as a suppressor in osteosarcoma and colorectal cancer, the physiological function of miR-598 in NSCLC remains unknown. In this study, the role of miR-598 in NSCLC was investigated. Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to estimate the expression of miR-598 and Derlin-1 (DERL1) in both NSCLC tissues and cell lines. Immunohistochemistry (IHC) analyzed the association between the miR-598 expression and epithelial-mesenchymal transition (EMT) hallmark genes (E-cadherin, Vimentin) by staining the tumors representative of the high- and low-expression groups. The effect of miR-598 and DERL1 on invasion and migration was determined in vitro using transwell and wound-healing assays. The molecular mechanism underlying the relevance between miR-598 and DERL1 was elucidated by luciferase assay and Western blot. Western blot assessed the expression levels of EMT hallmark genes in cell lines. Xenograft tumor formation assay was conducted as an in vivo experiment. Results: In this study, a relatively low level of miR-598 and high DERL1 expressions were found in NSCLC specimens and cell lines. IHC results established a positive correlation between the miR-598 expression and E-cadherin and a negative with Vimentin. DERL1 was verified as a direct target of miR-598 by luciferase assay. In vitro, the over-expression of miR-598 negatively regulated DERL1 and EMT for the suppression of invasion and migration. In vivo, the over-expression of miR-598 could inhibit tumor cell metastasis in NSCLC. Conclusions: These findings for the first time revealed that miR-598, as a tumor suppressor, negatively regulate DERL1 and EMT to suppress the invasion and migration in NSCLC, thereby putatively serving as a novel therapeutic target for NSCLC clinical treatment.


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Xiaohuan Xia ◽  
Hongfang Lu ◽  
Chunhong Li ◽  
Yunlong Huang ◽  
Yi Wang ◽  
...  

Abstract Background Recent studies suggested that miR-17~106 family was involved in the regulation of neural stem/progenitor cells (NPCs). However, distinct function of each family member was reported in regulating stem cells within and without the brain. Hence, to investigate the roles of individual miRNAs in miR-17~106 family and mechanisms underlying their effects on neurogenesis is important to extend our understanding in the CNS development. Methods Here, we examined the influence of miR-106a/b on the proliferation, differentiation, and survival of embryonic NPCs using specific mimics and inhibitor. The targets of miR-106a/b were identified from miRNA target prediction database and confirmed by luciferase assay. Specific siRNAs were utilized to erase the effects of miR-106a/b on the expression levels of target genes. Results A positive correlation was observed between the temporal reduction of miR-106a/b expression levels and the decline of NPC pools in vivo and in vitro. The perturbation of miR-106’s function approaches revealed that miR-106b, but not miR-106a, facilitated the maintenance of NPCs and repressed the generation of both neuronal and glial cells, without preference to a particular lineage. No effect was observed for miR-106a/b in NPCs’ survival. The influence of miR-106b on NPCs’ proliferation and differentiation is likely achieved by directly inhibiting the expression of Tp53inp1 and Cdkn1a, key components of Tp53inp1-Tp53-Cdkn1a axis. Conclusion Our study demonstrated a novel axis, miR-106b-Tp53inp1-Tp53-Cdkn1a, in regulating the proliferation and differentiation of NPCs.


2020 ◽  
Vol 17 (2) ◽  
pp. 125-132
Author(s):  
Marjanu Hikmah Elias ◽  
Noraziah Nordin ◽  
Nazefah Abdul Hamid

Background: Chronic Myeloid Leukaemia (CML) is associated with the BCRABL1 gene, which plays a central role in the pathogenesis of CML. Thus, it is crucial to suppress the expression of BCR-ABL1 in the treatment of CML. MicroRNA is known to be a gene expression regulator and is thus a good candidate for molecularly targeted therapy for CML. Objective: This study aims to identify the microRNAs from edible plants targeting the 3’ Untranslated Region (3’UTR) of BCR-ABL1. Methods: In this in silico analysis, the sequence of 3’UTR of BCR-ABL1 was obtained from Ensembl Genome Browser. PsRNATarget Analysis Server and MicroRNA Target Prediction (miRTar) Server were used to identify miRNAs that have binding conformity with 3’UTR of BCR-ABL1. The MiRBase database was used to validate the species of plants expressing the miRNAs. The RNAfold web server and RNA COMPOSER were used for secondary and tertiary structure prediction, respectively. Results: In silico analyses revealed that cpa-miR8154, csi-miR3952, gma-miR4414-5p, mdm-miR482c, osa-miR1858a and osa-miR1858b show binding conformity with strong molecular interaction towards 3’UTR region of BCR-ABL1. However, only cpa-miR- 8154, osa-miR-1858a and osa-miR-1858b showed good target site accessibility. Conclusion: It is predicted that these microRNAs post-transcriptionally inhibit the BCRABL1 gene and thus could be a potential molecular targeted therapy for CML. However, further studies involving in vitro, in vivo and functional analyses need to be carried out to determine the ability of these miRNAs to form the basis for targeted therapy for CML.


2021 ◽  
pp. 1-12
Author(s):  
Pengli Wang ◽  
Dan Zheng ◽  
Hongyang Qi ◽  
Qi Gao

BACKGROUND: MicroRNAs (miRNAs) play potential role in the development of various types of cancer conditions including pancreatic cancer (PC) targeting several cellular processes. Present study was aimed to evaluate function of miR-125b and the mechanism involved in PC. METHODS: Cell migration, MTT and BrdU study was done to establish the migration capability, cell viability and cell proliferation respectively. Binding sites for miR-125b were recognized by luciferase assay, expression of protein by western blot and immunofluorescence assay. In vivo study was done by BALB/c nude xenograft mice for evaluating the function of miR-125b. RESULTS: The study showed that expression of miR-125b was elevated in PC cells and tissues, and was correlated to proliferation and migration of cells. Also, over-expression of miR-125b encouraged migration, metastasis and proliferation of BxPC-3 cells, the suppression reversed it. We also noticed that thioredoxin-interacting protein (TXNIP) was the potential target of miR-125b. The outcomes also suggested that miR-125b governed the expression of TXNIP inversely via directly attaching to the 3′-UTR activating hypoxia-inducible factor 1α (HIF1α). Looking into the relation between HIF1α and TXNIP, we discovered that TXNIP caused the degradation and export of HIF1α by making a complex with it. CONCLUSION: The miR-125b-TXNIP-HIF1α pathway may serve useful strategy for diagnosing and treating PC.


Biomolecules ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 99 ◽  
Author(s):  
Danja J. Den Hartogh ◽  
Evangelia Tsiani

Type 2 diabetes mellitus (T2DM) is a metabolic disease characterized by insulin resistance and hyperglycemia and is associated with personal health and global economic burdens. Current strategies/approaches of insulin resistance and T2DM prevention and treatment are lacking in efficacy resulting in the need for new preventative and targeted therapies. In recent years, epidemiological studies have suggested that diets rich in vegetables and fruits are associated with health benefits including protection against insulin resistance and T2DM. Naringenin, a citrus flavanone, has been reported to have antioxidant, anti-inflammatory, hepatoprotective, nephroprotective, immunomodulatory and antidiabetic properties. The current review summarizes the existing in vitro and in vivo animal studies examining the anti-diabetic effects of naringenin.


Human Cell ◽  
2021 ◽  
Author(s):  
Jiaying Zhu ◽  
Zhu Zhu ◽  
Yipin Ren ◽  
Yukang Dong ◽  
Yaqi Li ◽  
...  

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.


2017 ◽  
Vol 2017 ◽  
pp. 1-16 ◽  
Author(s):  
Nahed El-Najjar ◽  
Rashmi P. Kulkarni ◽  
Nancy Nader ◽  
Rawad Hodeify ◽  
Khaled Machaca

Diabetes is a complex disease that is characterized with hyperglycemia, dyslipidemia, and insulin resistance. These pathologies are associated with significant cardiovascular implications that affect both the macro- and microvasculature. It is therefore important to understand the effects of various pathologies associated with diabetes on the vasculature. Here we directly test the effects of hyperglycemia on vascular smooth muscle (VSM) Ca2+signaling in an isolated in vitro system using the A7r5 rat aortic cell line as a model. We find that prolonged exposure of A7r5 cells to hyperglycemia (weeks) is associated with changes to Ca2+signaling, including most prominently an inhibition of the passive ER Ca2+leak and the sarcoplasmic reticulum Ca2+-ATPase (SERCA). To translate these findings to the in vivo condition, we used primary VSM cells from normal and diabetic subjects and find that only the inhibition of the ER Ca2+leaks replicates in cells from diabetic donors. These results show that prolonged hyperglycemia in isolation alters the Ca2+signaling machinery in VSM cells. However, these alterations are not readily translatable to the whole organism situation where alterations to the Ca2+signaling machinery are different.


2010 ◽  
Vol 24 (3) ◽  
pp. 632-643 ◽  
Author(s):  
Edward Arvisais ◽  
Xiaoying Hou ◽  
Todd A. Wyatt ◽  
Koumei Shirasuna ◽  
Heinrich Bollwein ◽  
...  

Abstract Little is known about the early intracellular events that contribute to corpus luteum regression. Experiments were designed to determine the effects of prostaglandin F2α (PGF2α) on phosphatidylinositol-3-kinase (PI3K)/Akt signaling in the corpus luteum in vivo and in vitro. Treatment of midluteal-phase cows with a luteolytic dose of PGF2α resulted in a rapid increase in ERK and mammalian target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase (p70S6K1) signaling and a rapid suppression of Akt phosphorylation in luteal tissue. In vitro treatment of primary cultures of luteal cells with PGF2α also resulted in an increase in ERK and mTOR/p70S6K1 signaling and a diminished capacity of IGF-I to stimulate PI3K, Akt, and protein kinase C ζ activation. Accounting for the reductions in PI3K and Akt activation observed in response to PGF2α treatment, we found that PGF2α promoted the phosphorylation of serine residues (307, 612, 636) in the insulin receptor substrate 1 (IRS1) peptide sequence in vivo and in vitro. Serine phosphorylation of IRS1 was associated with reduced formation of IGF-I-stimulated IRS1/PI3Kp85 complexes. Furthermore, treatment with inhibitors of the MAPK kinase 1/ERK or mTOR/p70S6K1 signaling pathways prevented PGF2α-induced serine phosphorylation of IRS1 and abrogated the inhibitory actions of PGF2α on Akt activation. Taken together, these experiments provide compelling evidence that PGF2α treatment stimulates IRS1 serine phosphorylation, which may contribute to a diminished capacity to respond to IGF-I. It seems likely that the rapid changes in phosphorylation events are among the early events that mediate PGF2α-induced corpus luteum regression.


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