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The epigenetic regulation of nuclear factor erythroid 2-related factor 2 (Nrf2), a pivotal redox transcription factor, plays a crucial role in maintaining cellular homeostasis. Recent research has underscored the significance of epigenetic modifications of Nrf2 in the pathogenesis of diabetic foot ulcers (DFUs). This study investigates the epigenetic reversal of Nrf2 by pterostilbene (PTS) in human endothelial cells in a hyperglycemic microenvironment (HGM). The activation potential of PTS on Nrf2 was evaluated through ARE-Luciferase reporter assays and nuclear translocation studies. Following 72 h of exposure to an HGM, mRNA expression and protein levels of Nrf2 and its downstream targets NAD(P)H quinone oxidoreductase 1 (NQO1), heme-oxygenase 1(HO-1), superoxide dismutase (SOD), and catalase (CAT) exhibited a decrease, which was mitigated in PTS-pretreated endothelial cells. Epigenetic markers, including histone deacetylases (HDACs class I-IV) and DNA methyltransferases (DNMTs 1/3A and 3B), were found to be downregulated under diabetic conditions. Specifically, Nrf2-associated HDACs, including HDAC1, HDAC2, HDAC3, and HDAC4, were upregulated in HGM-induced endothelial cells. This upregulation was reversed in PTS-pretreated cells, except for HDAC2, which exhibited elevated expression in endothelial cells treated with PTS in a hyperglycemic microenvironment. Additionally, PTS was observed to reverse the activity of the methyltransferase enzyme DNMT. Furthermore, CpG islands in the Nrf2 promoter were hypermethylated in cells exposed to an HGM, a phenomenon potentially counteracted by PTS pretreatment, as shown by methyl-sensitive restriction enzyme PCR (MSRE-qPCR) analysis. Collectively, our findings highlight the ability of PTS to epigenetically regulate Nrf2 expression under hyperglycemic conditions, suggesting its therapeutic potential in managing diabetic complications.
Assuntos
Antioxidantes , Células Endoteliais , Epigênese Genética , Hiperglicemia , Fator 2 Relacionado a NF-E2 , Estilbenos , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Humanos , Epigênese Genética/efeitos dos fármacos , Estilbenos/farmacologia , Hiperglicemia/metabolismo , Antioxidantes/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Microambiente Celular/efeitos dos fármacos , Histona Desacetilases/metabolismo , Histona Desacetilases/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Inativação Gênica , Estresse Oxidativo/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacosRESUMO
Diabetic nephropathy (DN), a severe complication of type 2 diabetes mellitus (T2DM), is marked by heightened endoplasmic reticulum stress (ERS) and oxidative stress (OS) due to protein misfolding and free radical generation. We investigated the sodium-glucose co-transporter-2 inhibitor (SGLT2i), canagliflozin (Cana), in alleviating ERS and OS in DN patients and THP-1 cells under hyperglycemic condition. A total of 120 subjects were divided into four groups, with 30 subjects in each group: healthy controls, T2DM individuals, DN patients receiving standard treatment, and those treated with Cana. The control group had no history of diabetes, cardiovascular or renal diseases, or other comorbidities. Cana was administered at doses of either 100 or 300 mg per day based on the estimated glomerular filtration rate (eGFR) value of DN individuals, with a mean follow-up of 6 months. Additionally, THP-1 monocytes were exposed to HGM (33.3 mM glucose with a cytokine cocktail of TNF-α and IFN-γ at 50 ng/mL each) to evaluate the relative levels of ERS, OS markers, and nuclear factor erythroid 2-related factor 2 (Nrf2), the transcription factor regulating cellular redox, which is downregulated in diabetes. Our results revealed that ERS markers GRP78 and PERK, as well as OS markers TXNIP and p22phox, were elevated in both DN patients and HGM-treated THP-1 monocytes and were reduced by Cana intervention. Furthermore, Cana regulated the phosphorylation of Nrf2, Akt, and EIF2α in HGM-treated monocytes. In conclusion, our findings highlight the role of Cana in activating Nrf2, thereby attenuating ERS and OS to mitigate DN progression.
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Recent evidence has implicated the role of microRNA-146a (miR-146a) in regulating inflammatory responses. In the present study, we investigated the role of miRNA-146a in the progression of diabetic foot ulcer (DFU) in type 2 diabetes mellitus patients (T2DM) and studied its correlation with stress mediators such as Endoplasmic Reticulum (ER) and oxidative stress. Ninety subjects were enrolled and evenly distributed among three groups: Controls (n = 30), T2DM without complications (n = 30) and T2DM with foot ulcers (n = 30). Subsequently, each group was further subdivided based on the University of Texas classification. Peripheral blood was collected from all the study subjects, while tissue biopsies were taken only from DFU patients. Total RNA from both PBMCs and wound tissues were isolated using miRNA isolation kit and qPCR was performed to check the expression of miR-146a, ER stress and oxidative stress markers. Our findings revealed a significant decrease in miR-146a expression among T2DM patients with Grade 2 and Grade 3 DFUs compared with those with Grade 0 and Grade 1 DFUs. Notably, inflammatory genes regulated by miR-146a, including TRAF6, IRAK-1 and ADAM, were all upregulated in T2DM patients with Grade 2 and Grade 3 DFUs. Moreover, reduced miR-146a levels were correlated with increased markers of ER stress and oxidative stress in Grade 2 and Grade 3 DFU patients. Furthermore, our in vitro experiment using mouse 3T3 fibroblasts demonstrated a downregulation of miR-146a following induction of hyperglycaemia, ER stress and oxidative stress in these cells. These findings suggest a potential link between diminished miR-146a expression and heightened oxidative and ER stress in T2DM patients with more severe grades of DFUs. Our results imply that targeting miR-146a may hold therapeutic promise for managing disease progression in DFU patients, as it could help alleviate oxidative and ER stress associated with diabetic complications.
Assuntos
Diabetes Mellitus Tipo 2 , Pé Diabético , Progressão da Doença , Estresse do Retículo Endoplasmático , Inflamação , MicroRNAs , Estresse Oxidativo , Humanos , Pé Diabético/metabolismo , Pé Diabético/patologia , MicroRNAs/metabolismo , MicroRNAs/genética , Masculino , Feminino , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Pessoa de Meia-Idade , Inflamação/metabolismo , Animais , Camundongos , IdosoRESUMO
Non-healing lesions in diabetic foot ulcers are a significant effect of poor angiogenesis. Epigenetic regulators, mainly lncRNA and miRNA, are recognized for their important roles in disease progression. We deciphered the regulation of lncRNA NEAT1 through the miR-146a-5p/mafG axis in the progression of DFU. A lowered expression of lncRNA NEAT1 was associated with dysregulated angiogenesis through the reduced expression of mafG, SDF-1α, and VEGF in chronic ulcer subjects compared to acute DFU. This was validated by silencing NEAT1 by SiRNA in the endothelial cells which resulted in the transcriptional repression of target genes. Our in silico analysis identified miR-146a-5p as a potential target of lncRNA NEAT1. Further, silencing NEAT1 led to an increase in the levels of miR-146a-5p in chronic DFU subjects. This research presents the role of the lncRNA NEAT1/miR-146a-5p/mafG axis in enhancing angiogenesis in DFU.
Assuntos
Pé Diabético , MicroRNAs , Neovascularização Fisiológica , RNA Longo não Codificante , Humanos , Pé Diabético/patologia , Células Endoteliais/metabolismo , MicroRNAs/genética , RNA Longo não Codificante/genéticaRESUMO
Vitamin D deficiency is prevalent in pregnancy and has been associated with increased occurrences of preeclampsia, cesarean delivery, neonatal bacterial vaginosis, and gestational diabetes. CYP24A1, recognized as a key factor in vitamin D metabolism homeostasis, encodes 24-hydroxylase responsible for converting 25(OH)D3 and 1,25(OH)2D3 into inactive metabolites. Recently, we have reported CYP24A1 overexpression in patients with gestational diabetes mellitus (GDM) and trophoblast cells exposed to hyperglycemia. In this study, we explored miRNA-mediated regulation of CYP24A1 in GDM progression, validating our findings through silencing experiments in a trophoblast cell line. In silico tools identified miR-125b-5p as a putative target of CYP24A1. Expression analysis revealed downregulation of miR-125b-5p in blood samples from early GDM and GDM compared to healthy pregnant women, positively correlating with vitamin D levels. Hyperglycemic exposure in human trophoblastic cell lines (BeWo) decreased miR-125b-5p expression, concomitant with an increase in CYP24A1. To confirm the regulatory role of miR-125b on CYP24A1, we transfected BeWo cells with antimiR-125b or miR-125b mimic. AntimiR-125b transfection heightened CYP24A1 levels, while miR-125b mimic overexpression resulted in decreased CYP24A1 expression. These findings establish miR-125b as a regulator of CYP24A1. To explore the influence of miR-125b on vitamin D metabolism, trophoblast cells overexpressing miR-125b were treated with 0.1 and 1 µM calcitriol. Hyperglycemic conditions exhibited a reduction in CYP24A1 levels. Collectively, our results indicate that miR-125b may regulate vitamin D metabolism by targeting CYP24A1, contributing to GDM progression. These findings may pave the way for understanding vitamin D resistance in concurrent GDM development and identifying novel miRNAs targeting CYP24A1.
Assuntos
Diabetes Gestacional , MicroRNAs , Feminino , Humanos , Recém-Nascido , Gravidez , Diabetes Gestacional/genética , Diabetes Gestacional/metabolismo , MicroRNAs/genética , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Vitamina D , Vitamina D3 24-Hidroxilase/genética , Vitamina D3 24-Hidroxilase/metabolismoRESUMO
The role of inflammasomes in gestational diabetes mellitus (GDM) has emerged as a critical area of research in recent years. Inflammasomes, key components of the innate immune system, are now recognized for their involvement in the pathogenesis of GDM. Activation of inflammasomes in response to various triggers during pregnancy can produce pro-inflammatory cytokines, such as interleukin-1ß (IL-1ß) and interleukin-18 (IL-18), contributing to systemic inflammation and insulin resistance. This dysregulation not only impacts maternal health but also poses significant risks to fetal development and long-term health outcomes. Understanding the intricate interplay between inflammasomes and GDM holds promise for developing novel therapeutic strategies and interventions to mitigate the adverse effects of this condition on both mothers and their offspring. Researchers have elucidated that targeting inflammasomes using anti-inflammatory drugs and compounds can effectively reduce inflammation in GDM. Furthermore, the addition of nuclear factor erythroid 2-related factor 2 (Nrf2) to this complex mechanism opens novel avenues for therapeutics. The antioxidant properties of Nrf2 may potentially suppress inflammasome activation in GDM. This comprehensive review investigates the intricate relationship between inflammasomes and GDM, emphasizing the pivotal role of inflammation in its pathogenesis. It also sheds light on potential therapeutic strategies targeting inflammasome activation and explores the role of Nrf2 in mitigating inflammation in GDM.
Assuntos
Diabetes Gestacional , Inflamassomos , Gravidez , Feminino , Humanos , Diabetes Gestacional/tratamento farmacológico , Fator 2 Relacionado a NF-E2 , Inflamação/tratamento farmacológico , Interleucina-1beta , Proteína 3 que Contém Domínio de Pirina da Família NLRRESUMO
Iron overload is linked to heightened susceptibility to ferroptosis, a process increasingly implicated in diabetes pathogenesis. This present study aims to assess the utility of Lactoferrin in predicting different stages of GDM and explore its association with disease pathology and ferroptosis. In this observational study, 72 pregnant women were recruited and categorized into three groups: healthy pregnant women without diabetes (NGDM, n = 24), early gestational diabetes (eGDM, n = 24), and established gestational diabetes (GDM, n = 24), all receiving standard antenatal care at 12 weeks of gestation. Circulating levels of ferritin, soluble transferrin receptor (sTFR), and Lactoferrin using multiplexed bead-based cytokine immunoassay. Gene expression analysis focused on analyzing crucial ferroptosis regulators, SLC7A11 and GPX4, in isolated peripheral blood mononuclear cells (PBMCs). A significant elevation in ferritin levels and a decrease in the sTFR: Ferritin ratio supported iron overload and disrupted iron homeostasis in GDM subjects. Notably, Lactoferrin levels were significantly lower in women with GDM than in the control group and those with eGDM. This decline in Lactoferrin correlated with increased hyperglycemia indicators and reduced expression of ferroptosis regulators among GDM patients. Furthermore ROC curve analysis demonstrated that Lactoferrin shows promise as a valuable marker for distinguishing individuals with GDM from those with eGDM. Lactoferrin shows promise as a biomarker for detecting GDM. These findings indicate its role as a potential biomarker and highlight Lactoferrin as a critical regulator of hyperglycemia and ferroptosis in women with GDM.
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Diabetes Gestacional , Ferroptose , Hiperglicemia , Sobrecarga de Ferro , Gravidez , Feminino , Humanos , Diabetes Gestacional/diagnóstico , Ferro/metabolismo , Lactoferrina/metabolismo , Leucócitos Mononucleares/metabolismo , Ferritinas , Receptores da Transferrina/metabolismo , BiomarcadoresRESUMO
Pterostilbene (PTS), known for its diverse beneficial effects via Nuclear factor erythroid-2 related factor (Nrf2) activation, holds potential for Diabetic Foot Ulcer (DFU) treatment. However, PTS-mediated Nrf2 regulation in diabetic wounds has yet to be elucidated. We used IC21 macrophage-conditioned media to simulate complex events that can influence the fibroblast phenotype using L929 cells during the wound healing process under a hyperglycemic microenvironment. We found that PTS attenuated fibroblast migration and alpha-smooth muscle actin (α-SMA) levels and hypoxia-inducible factor- 1 alpha (HIF1α). Furthermore, we demonstrated that wounds in diabetic mice characterized by impaired wound closure in a heightened inflammatory milieu, such as the NOD-like receptor P3 (NLRP3) and intercellular adhesion molecule 1 (ICAM1), and deficient Nrf2 response accompanying lowered Akt signaling and heme oxygenase1 (HO1) expression along with the impaired macrophage M2 marker CD206 expression, was rescued by administration of PTS. Such an elicited response was also compared favorably with the standard treatment using Regranex, a commercially available topical formulation for treating DFUs. Our findings suggest that PTS regulates Nrf2 in diabetic wounds, triggering a pro-wound healing response mediated by macrophages. This insight holds the potential for developing targeted therapies to heal chronic wounds, including DFUs.
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Diabetes Mellitus Experimental , Pé Diabético , Fator 2 Relacionado a NF-E2 , Estilbenos , Cicatrização , Animais , Camundongos , Diabetes Mellitus Experimental/complicações , Macrófagos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais , Cicatrização/efeitos dos fármacos , Estilbenos/farmacologia , Estilbenos/uso terapêutico , Pé Diabético/tratamento farmacológicoRESUMO
The nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor crucial in regulating cellular homeostasis and apoptosis. The NRF2 gene has been implicated in various biological activities, including antioxidant, anti-inflammatory, and anticancer properties. NRF2 can be regulated genetically and epigenetically at the transcriptional, post-transcriptional, and translational levels. Although DNA methylation is one of the critical biological processes vital for gene expression, sometimes, anomalous methylation patterns result in the dysregulation of genes and consequent diseases and disorders. Several studies have reported promoter hypermethylation downregulated NRF2 expression and its downstream targets. In contrast to the unalterable nature of genetic patterns, epigenetic changes can be reversed, opening up new possibilities in developing therapies for various metabolic disorders and diseases. This review discusses the current state of the NRF2-mediated antioxidative and chemopreventive activities of several natural phytochemicals, including sulforaphane, resveratrol, curcumin, luteolin, corosolic acid, apigenin, and most other compounds that have been found to activate NRF2. This epigenetic reversal of hypermethylated NRF2 states provides new opportunities for research into dietary phytochemistry that affects the human epigenome and the possibility for cutting-edge approaches to target NRF2-mediated signaling to prevent chronic disorders.
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Metilação de DNA , Fator 2 Relacionado a NF-E2 , Humanos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/genética , Epigênese Genética , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Doença Crônica , Polifenóis/farmacologiaRESUMO
Nuclear factor erythroid-2-related factor 2 (Nrf2) is a stress-activated transcription factor regulating antioxidant genes, and a deficiency thereof, slowing lymphangiogenesis, has been reported in diabetic foot ulcer (DFU). The mode of Nrf2 regulation in DFU has been less explored. Emerging studies on miRNA-mediated target regulation show miRNA to be the leading player in the pathogenesis of the disease. In the present study, we demonstrated the role of miR-27b in regulating Nrf2-mediated angiogenesis in DFU. A lower expression of mRNA targets, such as Nrf2, HO-1, SDF-1α, and VEGF, was observed in tissue biopsied from chronic DFU subjects, which was in line with miR-27b, signifying a positive correlation with Nrf2. Similarly, we found significantly reduced expression of miR-27b and target mRNAs Nrf2, HO-1, SDF-1α, and VEGF in endothelial cells under a hyperglycemic microenvironment (HGM). To confirm the association of miR-27b on regulating Nrf2-mediated angiogenesis, we inhibited its expression through RNA interference-mediated knockdown and observed disturbances in angiogenic signaling with reduced endothelial cell migration. In addition, to explore the role of miR-27b and angiogenesis in the activation of Nrf2, we pretreated the endothelial cells with two well-known pharmacological compounds-pterostilbene and resveratrol. We observed that activation of Nrf2 through these compounds ameliorates impaired angiogenesis on HGM-induced endothelial cells. This study suggests a positive role of miR-27b in regulating Nrf2, which seems to be decreased in DFU and improves on treatment with pterostilbene and resveratrol.
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Nuclear factor erythroid 2-related factor 2 (Nrf2), a transcriptional regulator, is the predominant factor in modulating oxidative stress and other cellular signaling responses. Studies from our lab and others highlighted that activation of the Nrf2 pathway by small molecules improves endothelial function by suppressing oxidative and endoplasmic reticulum (ER) stress. However, the exact mechanisms by which Nrf2 elicits these effects are unknown. In the present study, we developed CRISPR/Cas9-mediated Nrf2 knocked-out human endothelial cells, and proteomic signature was studied using LC-MS/MS. We identified 723 unique proteins, of which 361 proteins were found to be differentially regulated and further screened in the Nrf2ome online database, where we identified a highly interconnected signaling network in which 70 proteins directly interact with Nrf2. These proteins were found to regulate some key cellular and metabolic processes in the regulation actin cytoskeleton, ER stress, angiogenesis, inflammation, Hippo signaling pathway, and epidermal growth factor/fibroblast growth factor (EGF/FGF) signaling pathway. Our findings suggest the role of Nrf2 in maintaining endothelium integrity and its relationship with the crucial cellular processes which help develop novel therapeutics against endothelial dysfunction and its associated complications.
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Células Endoteliais , Fator 2 Relacionado a NF-E2 , Humanos , Cromatografia Líquida , Células Endoteliais/metabolismo , Endotélio Vascular , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Proteômica , Espectrometria de Massas em TandemRESUMO
Pancreatic beta-cell death has been established as a critical mediator in the progression of type 1 and type 2 diabetes mellitus. Beta-cell death is associated with exacerbating hyperglycemia and insulin resistance and paves the way for the progression of DM and its complications. Apoptosis has been considered the primary mechanism of beta-cell death in diabetes. However, recent pieces of evidence have implicated the substantial involvement of several other novel modes of cell death, including autophagy, pyroptosis, necroptosis, and ferroptosis. These distinct mechanisms are characterized by their unique biochemical features and often precipitate damage through the induction of cellular stressors, including endoplasmic reticulum stress, oxidative stress, and inflammation. Experimental studies were identified from PubMed literature on different modes of beta cell death during the onset of diabetes mellitus. This review summarizes current knowledge on the crucial pathways implicated in pancreatic beta cell death. The article also focuses on applying natural compounds as potential treatment strategies in inhibiting these cell death pathways.
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Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Apoptose/fisiologia , Células Secretoras de Insulina/metabolismo , Morte Celular , Estresse do Retículo Endoplasmático/genéticaRESUMO
Diabetes mellitus is associated with defects in islet ß-cell functioning and consequent hyperglycemia resulting in multi-organ damage. Physiologically relevant models that mimic human diabetic progression are urgently needed to identify new drug targets. Three-dimensional (3D) cell-culture systems are gaining a considerable interest in diabetic disease modelling and are being utilized as platforms for diabetic drug discovery and pancreatic tissue engineering. Three-dimensional models offer a marked advantage in obtaining physiologically relevant information and improve drug selectivity over conventional 2D (two-dimensional) cultures and rodent models. Indeed, recent evidence persuasively supports the adoption of appropriate 3D cell technology in ß-cell cultivation. This review article provides a considerably updated view of the benefits of employing 3D models in the experimental workflow compared to conventional animal and 2D models. We compile the latest innovations in this field and discuss the various strategies used to generate 3D culture models in diabetic research. We also critically review the advantages and the limitations of each 3D technology, with particular attention to the maintenance of ß-cell morphology, functionality, and intercellular crosstalk. Furthermore, we emphasize the scope of improvement needed in the 3D culture systems employed in diabetes research and the promises they hold as excellent research platforms in managing diabetes.
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Transcription factors regulate gene expression and play crucial roles in development and differentiation of pancreatic ß-cell. The expression and/or activities of these transcription factors are reduced when ß-cells are chronically exposed to hyperglycemia, which results in loss of ß-cell function. Optimal expression of such transcription factors is required to maintain normal pancreatic development and ß-cell function. Over many other methods of regenerating ß-cells, using small molecules to activate transcription factors has gained insights, resulting in ß-cells regeneration and survival. In this review, we discuss the broad spectrum of transcription factors regulating pancreatic ß-cell development, differentiation and regulation of these factors in normal and pathological states. Also, we have presented set of potential pharmacological effects of natural and synthetic compounds on activities of transcription factor involved in pancreatic ß-cell regeneration and survival. Exploring these compounds and their action on transcription factors responsible for pancreatic ß-cell function and survival could be useful in providing new insights for development of small molecule modulators.
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Células Secretoras de Insulina , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Diferenciação Celular , Pâncreas/metabolismo , Células Secretoras de Insulina/metabolismoRESUMO
Macrophages exhibit a high degree of plasticity that is physiologically relevant in wound healing, and disruption in normal macrophage response leads to delayed wound closure resulting in chronic wounds. Here, we attempt to discern macrophage responses to hemin via regulation of the nuclear factor-erythroid factor 2-related factor 2 (Nrf2) that could help us better understand the pathophysiology of diabetic foot ulcers (DFU). We demonstrate the alleviation of hemin-mediated Nrf2 suppression and M2 macrophage polarization by pterostilbene (PTS), a proven Nrf2 activator. IC-21 macrophages were treated with hemin under the normoglycemic or hyperglycemic environment with or without PTS and the expression levels of various markers, such as Nrf2 and its downstream target Heme Oxygenase-1 (HO-1), CD206, Ferroportin-1 among others were analyzed using qPCR and Western blot. Our results revealed that hemin under hyperglycemia reduced Nrf2 activation and its downstream targets, M2 polarization, and the induction of a proinflammatory cellular environment, and interestingly all of these were remedied by PTS treatment. Gelatin zymography of matrix metalloproteinase2 (MMP2) expression revealed that hemin under hyperglycemic condition significantly elevated MMP2 expression, which was reversed by PTS treatment. Further proteomic analysis using liquid chromatography with tandem mass spectrometry (LC-MS/MS) revealed a heightened cellular stress profile accompanying inflammation that was suppressed by PTS. This study has furthered our understanding on the role of Nrf2 in attenuating hemin-induced perturbations in macrophage responses and suggests a potential therapeutic target in the management of DFU.
Assuntos
Hemina , Macrófagos , Fator 2 Relacionado a NF-E2 , Estilbenos , Hemina/efeitos adversos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Polaridade Celular , Hiperglicemia , Fator 2 Relacionado a NF-E2/metabolismo , Pé Diabético , Estilbenos/farmacologia , Animais , Camundongos , Linhagem CelularRESUMO
OBJECTIVE: The present study was conducted to explore the allele frequencies of MICA gene Exon-5 transmembrane and to measure the circulatory MICA levels in various histologic grades of patients with oral submucous fibrosis (OSF) compared to healthy individuals. STUDY DESIGN: We enrolled a total of 595 patients for this cross-sectional study and divided them into 2 groups: healthy controls (n = 320) and patients with OSF (n = 275). Further, patients with OSF were subdivided based on their histologic gradings. The genomic DNA was extracted followed by a polymerase chain reaction and genotyping using the ABI Prism DNA Sequencer (ThermoFisher Scientific, Inc., Waltham, MA, USA). RESULTS: Our study showed that the A5 allele of the MICA gene in the Exon-5 region conferred significant risk for patients with OSF. With reference to the histologic gradings of OSF, we found that the MICA gene conferred statistically significant risk among patients with grade III OSF. On the other hand, the A8 allele of MICA gene in the Exon-5 region conferred significant protection among the overall OSF cohort and in the grade III of histologic grade. Finally, the circulatory human MICA levels were found to have a stepwise increase from grade I toward grade III in patients with OSF. CONCLUSION: Our results suggested that the A5 allele in MICA might confer risk for the progression of OSF among the South Indian ethnic population.
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Fibrose Oral Submucosa , Humanos , Estudos Transversais , Éxons/genética , Frequência do Gene/genética , Antígenos de Histocompatibilidade Classe I , Fibrose Oral Submucosa/genética , Polimorfismo Genético/genéticaRESUMO
Chronic hyperglycemia damages the nerves and blood vessels, culminating in other vascular complications. Such complications enhance cytokine, oxidative and endoplasmic reticulum (ER) stress. ER is the primary organelle where proteins are synthesised and attains confirmatory changes before its site of destination. Perturbation of ER homeostasis activates signaling sensors within its lumen, the unfolded protein response (UPR) that orchestrates ER stress and is extensively studied. Increased ER stress markers are reported in diabetic complications in addition to lncRNA that acts as an upstream marker inducing ER stress response. This review focuses on the mechanisms of lncRNA that regulate ER stress markers, especially during the progression of diabetic complications. Through this systemic review, we showcase the dysfunctional lncRNAs that act as a leading cause of ER stress response to the progression of diabetic complications.
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Complicações do Diabetes , Diabetes Mellitus , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Estresse do Retículo Endoplasmático/genética , Resposta a Proteínas não Dobradas/genética , Complicações do Diabetes/genética , Proteínas/metabolismo , Diabetes Mellitus/genéticaRESUMO
Circular RNA (circRNA) is a neoteric researched transcript that involves gene regulation by serving as a micro-RNA (miRNA) sponge. This circRNA-miRNA-mRNA interaction is being recently explored, and its dysregulation is associated with disease pathogenesis and progression. Studies have demonstrated the involvement of this regulatory network in endothelium dysfunction-mediated regulation of pathology in vascular diseases. The disturbances or imbalance of vasodilation and vasoconstriction factors due to changes in oxidative stress, inflammatory markers, and nitric oxide signaling leads to endothelial dysfunction. These disturbances cause impermeability of blood through the endothelial barrier, thus developing atherosclerotic lesions. Advancements in high-throughput techniques like genome and RNA sequencing have made us understand this complex regulatory network causing endothelial dysfunction. In this review, we emphasize the network of interactions between circRNA, miRNA, and mRNA that mediates gene regulation and is linked to endothelial dysfunction in various pathological conditions.
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MicroRNAs , Doenças Vasculares , Humanos , RNA Circular/genética , MicroRNAs/genética , RNA Mensageiro/genética , Redes Reguladoras de Genes , Doenças Vasculares/genéticaRESUMO
The regulation of angiogenesis by nuclear factor erythroid 2-related factor 2 (Nrf2), a master redox transcription factor, is well established. In the present study, we aimed to activate Nrf2 by mangiferin (MG) and investigate its potential to regulate angiogenesis under a hyperglycemic (HG) environment in human endothelial cells. The mRNA expression of Nrf2 and its downstream targets HO-1, SOD-1, and CAT were observed to be decreased at 72 h of HG (33.3 mM glucose) exposure, and was ameliorated in MG (24 h) pretreated endothelial cells. ROS generation was assessed using an DCFDA assay, where we found the ROS generated at HG exposure was quenched by MG in a dose-dependent manner. The angiogenic markers HIF-1α and VEGF were also decreased in HG-induced endothelial cells, which significantly increased in the cells pretreated with MG. In addition, we have observed substantially more closed tube network formation in MG pretreated cells, which was low in HG-induced endothelial cells. The cell migration potential was monitored using a scratch assay, where the cells activated by MG showed a more significant movement than those under HG stress. Furthermore, to understand the role of Nrf2 in regulating angiogenesis, we knocked out the Nrf2 using CRISPR/Cas9 in endothelial cells. The wild-type endothelial cells exposed to MG alone showed a cytoprotective effect under a hyperglycemic environment. Our findings collectively demonstrated that MG helps regulate impaired angiogenesis under a hyperglycemic environment through Nrf2 signaling.