High Glucose Reduces the Paracellular Permeability of the Submandibular Gland Epithelium via the MiR-22-3p/Sp1/Claudin Pathway

Tight junctions (TJs) play an important role in water, ion, and solute transport through the paracellular pathway of epithelial cells; however, their role in diabetes-induced salivary gland dysfunction remains unknown. Here, we found that the TJ proteins claudin-1 and claudin-3 were significantly increased in the submandibular glands (SMGs) of db/db mice and high glucose (HG)-treated human SMGs. HG decreased paracellular permeability and increased claudin-1 and claudin-3 expression in SMG-C6 cells. Knockdown of claudin-1 or claudin-3 reversed the HG-induced decrease in paracellular permeability. MiR-22-3p was significantly downregulated in diabetic SMGs and HG-treated SMG-C6 cells. A miR-22-3p mimic suppressed claudin-1 and claudin-3 expression and abolished the HG-induced increases in claudin-1 and claudin-3 levels in SMG-C6 cells, whereas a miR-22-3p inhibitor produced the opposite effects. Specificity protein-1 (Sp1) was enhanced in diabetic SMGs and HG-treated SMG-C6 cells, which promoted claudin-1 and claudin-3 transcription through binding to the corresponding promoters. A luciferase reporter assay confirmed that miR-22-3p repressed Sp1 by directly targeting the Sp1 mRNA 3′-untranslated region (3′-UTR). Consistently, the miR-22-3p mimic suppressed, whereas the miR-22-3p inhibitor enhanced, the effects of HG on Sp1 expression. Taken together, our results demonstrate a new regulatory pathway through which HG decreases the paracellular permeability of SMG cells by inhibiting miR-22-3p/Sp1-mediated claudin-1 and claudin-3 expression.

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MicroRNA-124 controls human vascular smooth muscle cell phenotypic switch via Sp1

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00660.2016 ◽

2017 ◽

Vol 313 (3) ◽

pp. H641-H649 ◽

Cited By ~ 21

Author(s):

Yangfeng Tang ◽

Shangyi Yu ◽

Yang Liu ◽

Jiajun Zhang ◽

Lin Han ◽

...

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cell ◽

Muscle Cell ◽

Vascular Smooth Muscle Cell ◽

Untranslated Region ◽

Phenotypic Switch ◽

Specificity Protein 1 ◽

Microrna 124 ◽

Specificity Protein

Phenotypic switch of vascular smooth muscle cells (VSMCs) plays an important role in the pathogenesis of atherosclerosis and aortic dissection. However, the mechanisms of phenotypic modulation are still unclear. MicroRNAs have emerged as important regulators of VSMC function. We recently found that microRNA-124 (miR-124) was downregulated in proliferative vascular diseases that were characterized by a VSMC phenotypic switch. Therefore, we speculated that the aberrant expression of miR-124 might play a critical role in human aortic VSMC phenotypic switch. Using quantitative RT-PCR, we found that miR-124 was dramatically downregulated in the aortic media of clinical specimens of the dissected aorta and correlated with molecular markers of the contractile VSMC phenotype. Overexpression of miR-124 by mimicking transfection significantly attenuated platelet-derived growth factor-BB-induced human aortic VSMC proliferation and phenotypic switch. Furthermore, we identified specificity protein 1 (Sp1) as the downstream target of miR-124. A luciferase reporter assay was used to confirm direct miR-124 targeting of the 3′-untranslated region of the Sp1 gene and repression of Sp1 expression in human aortic VSMCs. Furthermore, constitutively active Sp1 in miR-124-overexpressing VSMCs reversed the antiproliferative effects of miR-124. These results demonstrated a novel mechanism of miR-124 modulation of VSMC phenotypic switch by targeting Sp1 expression. NEW & NOTEWORTHY Previous studies have demonstrated that miR-124 is involved in the proliferation of a variety of cell types. However, miRNAs are expressed in a tissue-specific manner. We first identified miR-124 as a critical regulator in human aortic vascular smooth muscle cell differentiation, proliferation, and phenotype switch by targeting the 3′-untranslated region of specificity protein 1.

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Thiamine transporter 2 is involved in high glucose-induced damage and altered thiamine availability in cell models of diabetic retinopathy

Diabetes and Vascular Disease Research ◽

10.1177/1479164119878427 ◽

2019 ◽

Vol 17 (1) ◽

pp. 147916411987842 ◽

Cited By ~ 1

Author(s):

Elena Beltramo ◽

Aurora Mazzeo ◽

Tatiana Lopatina ◽

Marina Trento ◽

Massimo Porta

Keyword(s):

Transcription Factor ◽

Diabetic Retinopathy ◽

High Glucose ◽

Cell Models ◽

Blood Retinal Barrier ◽

Transketolase Activity ◽

Specificity Protein 1 ◽

Thiamine Transport ◽

Factor Specificity ◽

Specificity Protein

Thiamine prevents high glucose-induced damage in microvasculature, and progression of retinopathy and nephropathy in diabetic animals. Impaired thiamine availability causes renal damage in diabetic patients. Two single-nucleotide polymorphisms in SLC19A3 locus encoding for thiamine transporter 2 are associated with absent/minimal diabetic retinopathy and nephropathy despite long-term type 1 diabetes. We investigated the involvement of thiamine transporter 1 and thiamine transporter 2, and their transcription factor specificity protein 1, in high glucose-induced damage and altered thiamine availability in cells of the inner blood–retinal barrier. Human endothelial cells, pericytes and Müller cells were exposed to hyperglycaemic-like conditions and/or thiamine deficiency/over-supplementation in single/co-cultures. Expression and localization of thiamine transporter 1, thiamine transporter 2 and transcription factor specificity protein 1 were evaluated together with intracellular thiamine concentration, transketolase activity and permeability to thiamine. The effects of thiamine depletion on cell function (viability, apoptosis and migration) were also addressed. Thiamine transporter 2 and transcription factor specificity protein 1 expression were modulated by hyperglycaemic-like conditions. Transketolase activity, intracellular thiamine and permeability to thiamine were decreased in cells cultured in thiamine deficiency, and in pericytes in hyperglycaemic-like conditions. Thiamine depletion reduced cell viability and proliferation, while thiamine over-supplementation compensated for thiamine transporter 2 reduction by restoring thiamine uptake and transketolase activity. High glucose and reduced thiamine determine impairment in thiamine transport inside retinal cells and through the inner blood–retinal barrier. Thiamine transporter 2 modulation in our cell models suggests its major role in thiamine transport in retinal cells and its involvement in high glucose-induced damage and impaired thiamine availability.

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Characterization of the human topoisomerase IIβ (TOP2B) promoter activity: essential roles of the nuclear factor-Y (NF-Y)- and specificity protein-1 (Sp1)-binding sites

Biochemical Journal ◽

10.1042/bj20020791 ◽

2002 ◽

Vol 368 (3) ◽

pp. 741-751 ◽

Cited By ~ 19

Author(s):

Chun-Nam LOK ◽

Alexander J. LANG ◽

Shelagh E.L. MIRSKI ◽

Susan P.C. COLE

Keyword(s):

Binding Sites ◽

Promoter Activity ◽

Luciferase Reporter ◽

Cancer Drug ◽

Resting Cells ◽

Nuclear Factor ◽

Nuclear Factor Y ◽

Specificity Protein 1 ◽

Topo Ii ◽

Specificity Protein

Eukaryotic topoisomerase II (topo II) catalyses topological genomic changes essential for chromosome segregation, chromatin reorganization, DNA replication and transcription. Mammalian topo II exists as two isoforms, designated α and β. Human topo IIα is an important cancer drug target, and an established determinant of drug sensitivity and resistance. Human topo IIβ is also the target of anticancer drugs but its role in drug resistance is less clear. The two human topo II proteins are encoded by the TOP2A and TOP2B genes, respectively, which despite their highly conserved structural organization, are subject to distinctly different modes of regulation. In the present study, we have cloned and characterized the human TOP2B promoter containing a 1.3kb fragment of the 5′-flanking and untranslated region (-1067 to +193). We found that the promoter activity of this TOP2B fragment was constant throughout the cell cycle, in contrast to the activity of the proximal promoter of TOP2A which was low in resting cells and enhanced during proliferation. Analyses of 5′-serially and internally deleted luciferase reporter constructs revealed that 80% of the TOP2B promoter activity could be attributed to the region between −533 and −481. Mutational analyses of putative regulatory elements indicated that two inverted CCAAT boxes (ICBs) within this region were essential for TOP2B promoter activity and gel mobility-shift assays indicated these sites bound the transcription factor nuclear factor-Y (NF-Y). Co-transfection experiments using a dominant-negative form of subunit A of NF-Y suggested that TOP2B promoter activity required direct interaction of NF-Y with the ICBs. In addition, a specificity protein-1 (Sp1)-binding GC box located just upstream of the ICBs was shown to contribute to TOP2B promoter activity in a synergistic manner with the ICBs. Our results suggest that the binding sites for NF-Y and Sp1 are critical for TOP2B transcription.

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Sequential Activation of Hypoxia-Inducible Factor 1 and Specificity Protein 1 is Required for Hypoxia-Induced Transcriptional Stimulation of Abcc8

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2011.159 ◽

2011 ◽

Vol 32 (3) ◽

pp. 525-536 ◽

Cited By ~ 37

Author(s):

Seung Kyoon Woo ◽

Min Seong Kwon ◽

Zhihua Geng ◽

Zheng Chen ◽

Alexander Ivanov ◽

...

Keyword(s):

Cerebral Ischemia ◽

Binding Sites ◽

Hypoxia Inducible Factor ◽

Luciferase Reporter ◽

Hypoxia Inducible Factor 1 ◽

Specificity Protein 1 ◽

Reporter Assays ◽

Sequential Activation ◽

Specificity Protein ◽

Stimulation Of

Cerebral ischemia causes increased transcription of sulfonylurea receptor 1 (SUR1), which forms SUR1-regulated NC(Ca-ATP) channels linked to cerebral edema. We tested the hypothesis that hypoxia is an initial signal that stimulates transcription of Abcc8, the gene encoding SUR1, via activation of hypoxia-inducible factor 1 (HIF1). In the brain microvascular endothelial cells, hypoxia increased SUR1 abundance and expression of functional SUR1-regulated NC(Ca-ATP) channels. Luciferase reporter activity driven by the Abcc8 promoter was increased by hypoxia and by coexpression of HIF1α. Surprisingly, a series of luciferase reporter assays studying the Abcc8 promoter revealed that binding sites for specificity protein 1 (Sp1), but not for HIF, were required for stimulation of Abcc8 transcription by HIF1α. Luciferase reporter assays studying Sp1 promoters of three species, and chromatin immunoprecipitation analysis in rats after cerebral ischemia, indicated that HIF binds to HIF-binding sites on the Sp1 promoter to stimulate transcription of the Sp1 gene. We conclude that sequential activation of two transcription factors, HIF and Sp1, is required to stimulate transcription of Abcc8 following cerebral ischemia. Sequential gene activation in cerebral ischemia provides a plausible molecular explanation for the prolonged treatment window observed for inhibition of the end-target gene product, SUR1, by glibenclamide.

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Integrative analysis of competitive endogenous RNA network reveals the regulatory role of non-coding RNAs in high-glucose-induced human retinal endothelial cells

PeerJ ◽

10.7717/peerj.9452 ◽

2020 ◽

Vol 8 ◽

pp. e9452

Author(s):

Nan-Jue Cao ◽

He-Nan Liu ◽

Feng Dong ◽

Wei Wang ◽

Wei Sun ◽

...

Keyword(s):

Endothelial Cells ◽

High Glucose ◽

Luciferase Reporter ◽

Reporter Assay ◽

Ppi Network ◽

Hub Genes ◽

Retinal Endothelial Cells ◽

Qrt Pcr ◽

Cerna Network ◽

Non Coding Rnas

Background Increasing evidence has suggested that non-coding RNAs (ncRNAs) play critical roles in the pathogenesis of diabetic retinopathy (DR), but their underlying mechanisms remain unclear. The purpose of this study was to determine latent key genes and to structure a competing endogenous RNA (ceRNA) regulatory network to discover the potential molecular mechanisms governing the effects of high glucose on human retinal endothelial cells (HRECs). Methods We obtained microarray data for long non-coding RNA (lncRNA) and mRNA of high-glucose-induced HREC samples from NCBI GEO datasets. The ceRNA network was screened using intersecting prediction results from miRcode, TargetScan, miRTarBase and miRDB. The protein–protein interaction (PPI) network was constructed using the Search Tool for the Retrieval of Interacting Genes and hub genes were obtained using the cytoHubba app. The ClusterProfiler package was applied for performing Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The expression of key RNAs was verified using the qRT-PCR method. A key ceRNA subnetwork was constructed based on the criticality of the genes and its binding sites were verified by luciferase reporter assay. The viability and apoptosis of HRECs were tested using the transfection of the miR-449c inhibitor. Results A total of 3,328 lncRNAs and 2,017 mRNAs were screened for differentially expressed (DE) profiles. The newly constructed ceRNA network was composed of 410 lncRNAs, 35 miRNAs and 122 mRNAs. The 10 hub genes were identified through the PPI network. GO and KEGG analysis revealed that DE mRNAs were mainly related to the positive regulation of the mRNA catabolic process, cell polarity, and the G1/S transition of mitotic and cell cycle signaling pathways. QRT-PCR was used to verify RNAs and the most important genes were screened out. A key ceRNA subnetwork OIP5-AS1/miR-449c/MYC was established. The binding site was verified by luciferase reporter assay. The expression levels of OIP5-AS1 and MYC increased after miR-449c inhibitor transfection, miR-449c decreased, HRECs activity increased, and apoptosis decreased, compared with the control group. Conclusion We successfully built the key ceRNA subnetwork, OIP5-AS1/miR-449c/MYC, by applying the GEO database for data analysis and mining. The results from the ceRNA network allow us to better understand the effect of ncRNAs on HRECs under hyperglycemic conditions and the pathogenesis of DR.

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MiR-144-3p Inhibits BMSC Proliferation and Osteogenic Differentiation Via Targeting FZD4 in Steroid-Associated Osteonecrosis

Current Pharmaceutical Design ◽

10.2174/1381612825666190930094019 ◽

2020 ◽

Vol 25 (45) ◽

pp. 4806-4812 ◽

Cited By ~ 3

Author(s):

Zhibo Sun ◽

Fei Wu ◽

Yue Yang ◽

Feng Liu ◽

Fengbo Mo ◽

...

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Nuclear Translocation ◽

Bone Diseases ◽

Luciferase Reporter ◽

Reporter Assay ◽

Alizarin Red ◽

Over Expression ◽

Negative Effect ◽

Proliferation Ability

Background: MicroRNAs have recently been recognized to be engaged in the development of bone diseases. Objective: This study was performed to elucidate the effects of miR-144-3p on proliferation and osteogenesis of mesenchymal stem cells (MSCs) from the patients with steroid-associated osteonecrosis (ONFH) and its related mechanism. Method: The expression level of miR-144-3p in the MSCs from the proximal femur of the patients was examined by Real-time PCR. The cell proliferation ability was assayed by MTT. The differentiation ability of MSCs was assayed by Alizarin Red S (ARS) staining. The interaction between miR-144-3p and frizzled4 (FZD4) was investigated by Real-time PCR, western blot and luciferase reporter assay. Results: ONFH samples had the obviously high expression of miR-144-3p compared to the control. MiR-144-3p had a negative effect on the proliferation and osteogenesis of MSCs. Via targeting FZD4, miR-144-3p decreased β-catenin nuclear translocation, the transcription of RUNX2 and COL1A1. Over-expression of FZD4 partially reversed miR-144-3p-induced decrease in the proliferation and osteogenesis of MSCs. Conclusion: MiR-144-3p might play an important role in the development of ONFH and might be used as a novel class of therapeutic targets for this disease.

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Long noncoding RNA OIP5-AS1 overexpression promotes viability and inhibits high glucose-induced oxidative stress of cardiomyocytes by targeting microRNA-34a/SIRT1 axis in diabetic cardiomyopathy

Endocrine Metabolic & Immune Disorders - Drug Targets ◽

10.2174/1871530321666201230090742 ◽

2020 ◽

Vol 21 ◽

Author(s):

Haiyun Sun ◽

Chong Wang ◽

Ying Zhou ◽

Xingbo Cheng

Keyword(s):

Oxidative Stress ◽

Protein Expression ◽

Diabetic Cardiomyopathy ◽

High Glucose ◽

Long Noncoding Rna ◽

Noncoding Rna ◽

Luciferase Reporter ◽

H9c2 Cells ◽

Promoting Effect

Objective: Diabetic cardiomyopathy (DCM) is an important complication of diabetes. This study was attempted to discover the effects of long noncoding RNA OIP5-AS1 (OIP5-AS1) on the viability and oxidative stress of cardiomyocyte in DCM. Methods: The expression of OIP5-AS1 and microRNA-34a (miR-34a) in DCM was detected by qRT-PCR. In vitro, DCM was simulated by high glucose (HG, 30 mM) treatment in H9c2 cells. The viability of HG (30 mM)-treated H9c2 cells was examined by MTT assay. The reactive oxygen species (ROS), superoxide dismutase (SOD) and malondialdehyde (MDA) levels were used to evaluate the oxidative stress of HG (30 mM)-treated H9c2 cells. Dual-luciferase reporter assay was used to confirm the interactions among OIP5-AS1, miR-34a and SIRT1. Western blot was applied to analyze the protein expression of SIRT1. Results: The expression of OIP5-AS1 was down-regulated in DCM, but miR-34a was up-regulated. The functional experiment stated that OIP5-AS1 overexpression increased the viability and SOD level, while decreased the ROS and MDA levels in HG (30 mM)-treated H9c2 cells. The mechanical experiment confirmed that OIP5-AS1 and SIRT1 were both targeted by miR-34a with the complementary binding sites at 3′UTR. MiR-34a overexpression inhibited the protein expression of SIRT1. In the feedback experiments, miR-34a overexpression or SIRT1 inhibition weakened the promoting effect on viability, and mitigated the reduction effect on oxidative stress caused by OIP5-AS1 overexpression in HG (30 mM)-treated H9c2 cells. Conclusions: OIP5-AS1 overexpression enhanced viability and attenuated oxidative stress of cardiomyocyte via regulating miR-34a/SIRT1 axis in DCM, providing a new therapeutic target for DCM.

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MicroRNA-513b-5p targets COL1A1 and COL1A2 associated with the formation and rupture of intracranial aneurysm

Scientific Reports ◽

10.1038/s41598-021-94116-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Zheng Zheng ◽

Yan Chen ◽

Yinzhou Wang ◽

Yongkun Li ◽

Qiong Cheng

Keyword(s):

Cell Death ◽

Intracranial Aneurysm ◽

Luciferase Reporter Assay ◽

Luciferase Reporter ◽

Control Group ◽

Type I ◽

Mrna Levels ◽

Reporter Assay ◽

Over Expression ◽

Tnf Α

AbstractCollagen-type I alpha 1 chain (COL1A1) and COL1A2 are abnormally expressed in intracranial aneurysm (IA), but their mechanism of action remains unclear. This study was performed to investigate the mechanism of COL1A1 and COL1A2 affecting the occurrence and rupture of IA. Quantitative real-time polymerase chain reaction was used to measure the expression of hsa-miR-513b-5p, COL1A1, COL1A2, TNF-α, IL-6, MMP2, MMP3, MMP9 and TIMP4 in patients with ruptured IA (RA) (n = 100), patients with un-ruptured IA (UA) (n = 100), and controls (n = 100). Then, human vascular smooth muscle cells (HASMCs) were cultured, and dual luciferase reporter assay was performed to analyse the targeting relationship between miR-513b-5p and COL1A1 or COL1A2. The effects of the miR-513b-5p mimic and inhibitor on the proliferation, apoptosis, and death of HASMC and the RIP1-RIP3-MLKL and matrix metalloproteinase pathways were also explored. The effect of silencing and over-expression of COL1A1 and COL1A2 on the role of miR-513b-5p were also evaluated. Finally, the effects of TNF-α on miR-513b-5p targeting COL1A1 and COL1A2 were tested. Compared with those in the control group, the serum mRNA levels of miR-513b-5p, IL-6 and TIMP4 were significantly decreased in the RA and UA groups, but COL1A1, COL1A2, TNF-α, IL-1β, MMP2, MMP3 and MMP9 were significantly increased (p < 0.05). Compared with those in the UA group, the expression of COL1A1, COL1A2, TNF-α, IL-1β and MMP9 was significantly up-regulated in the RA group (p < 0.05). Results from the luciferase reporter assay showed that COL1A1 and COL1A were the direct targets of miR-513b-5p. Further studies demonstrated that miR-513b-5p targeted COL1A1/2 to regulate the RIP1-RIP3-MLKL and MMP pathways, thereby enhancing cell death and apoptosis. Over-expression of COL1A1 or COL1A2, rather than silencing COL1A1/2, could improve the inhibitory effect of miR-513b-5p on cell activity by regulating the RIP1-RIP3-MLKL and MMP pathways. Furthermore, over-expression of miR-513b-5p and/or silencing COL1A1/2 inhibited the TNF-α-induced cell proliferation and enhanced the TNF-α-induced cell death and apoptosis. The mechanism may be related to the inhibition of collagen I and TIMP4 expression and promotion of the expression of RIP1, p-RIP1, p-RIP3, p-MLKL, MMP2 and MMP9. MiR-513b-5p targeted the inhibition of COL1A1/2 expression and affected HASMC viability and extracellular mechanism remodelling by regulating the RIP1-RIP3-MLKL and MMP pathways. This process might be involved in the formation and rupture of IA.

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Circ-ACTR2 aggravates the high glucose-induced cell dysfunction of human renal mesangial cells through mediating the miR-205-5p/HMGA2 axis in diabetic nephropathy

Diabetology & Metabolic Syndrome ◽

10.1186/s13098-021-00692-x ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Jie Yun ◽

Jinyu Ren ◽

Yufei Liu ◽

Lijuan Dai ◽

Liqun Song ◽

...

Keyword(s):

Oxidative Stress ◽

Diabetic Nephropathy ◽

High Glucose ◽

Cell Injury ◽

Mesangial Cells ◽

Protein Detection ◽

Cell Counting ◽

Luciferase Reporter ◽

Enzyme Linked Immunosorbent Assay ◽

Cell Dysfunction

Abstract Background Circular RNAs (circRNAs) have been considered as pivotal biomarkers in Diabetic nephropathy (DN). CircRNA ARP2 actin-related protein 2 homolog (circ-ACTR2) could promote the HG-induced cell injury in DN. However, how circ-ACTR2 acts in DN is still unclear. This study aimed to explore the molecular mechanism of circ-ACTR2 in DN progression, intending to provide support for the diagnostic and therapeutic potentials of circ-ACTR2 in DN. Methods RNA expression analysis was conducted by the quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Cell growth was measured via Cell Counting Kit-8 and EdU assays. Inflammatory response was assessed by Enzyme-linked immunosorbent assay. The protein detection was performed via western blot. Oxidative stress was evaluated by the commercial kits. The molecular interaction was affirmed through dual-luciferase reporter and RNA immunoprecipitation assays. Results Circ-ACTR2 level was upregulated in DN samples and high glucose (HG)-treated human renal mesangial cells (HRMCs). Silencing the circ-ACTR2 expression partly abolished the HG-induced cell proliferation, inflammation and extracellular matrix accumulation and oxidative stress in HRMCs. Circ-ACTR2 was confirmed as a sponge for miR-205-5p. Circ-ACTR2 regulated the effects of HG on HRMCs by targeting miR-205-5p. MiR-205-5p directly targeted high-mobility group AT-hook 2 (HMGA2), and HMGA2 downregulation also protected against cell injury in HG-treated HRMCs. HG-mediated cell dysfunction was repressed by miR-205-5p/HMGA2 axis. Moreover, circ-ACTR2 increased the expression of HMGA2 through the sponge effect on miR-205-5p in HG-treated HRMCs. Conclusion All data have manifested that circ-ACTR2 contributed to the HG-induced DN progression in HRMCs by the mediation of miR-205-5p/HMGA2 axis.

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