Project description:MicroRNAs are powerful gene expression regulators, but their corneal repertoire and potential changes in corneal diseases remain unknown. Our purpose was to identify miRNAs altered in the human diabetic cornea by microarray analysis, and to examine their effects on wound healing in cultured telomerase-immortalized human corneal epithelial cells (HCEC) in vitro. Using microarrays, 29 miRNAs were identified as differentially expressed in diabetic samples. Two miRNA candidates showing the highest fold increased in expression in the diabetic cornea were confirmed by Q-PCR and further characterized. HCEC transfection with h-miR-146a or h-miR-424 significantly retarded wound closure, but their respective antagomirs significantly enhanced wound healing vs. controls. Cells treated with h-miR-146a or h-miR-424 had decreased p-p38 and p-EGFR staining, but these increased over control levels close to the wound edge upon antagomir treatment. In conclusion, several miRNAs with increased expression in human diabetic central corneas were found. Two such miRNAs inhibited cultured corneal epithelial cell wound healing. Dysregulation of miRNA expression in human diabetic cornea may be an important mediator of abnormal wound healing. Total RNA was extracted from age-matched human autopsy normal (n=6) and diabetic (n=6) central corneas, Flash Tag end-labeled, and hybridized to Affymetrix® GeneChip® miRNA Arrays. Select miRNAs associated with diabetic cornea were validated by quantitative RT-PCR (Q-PCR) and by in situ hybridization (ISH) in independent samples.
Project description:MicroRNAs are powerful gene expression regulators, but their corneal repertoire and potential changes in corneal diseases remain unknown. Our purpose was to identify miRNAs altered in the human diabetic cornea by microarray analysis, and to examine their effects on wound healing in cultured telomerase-immortalized human corneal epithelial cells (HCEC) in vitro. Using microarrays, 29 miRNAs were identified as differentially expressed in diabetic samples. Two miRNA candidates showing the highest fold increased in expression in the diabetic cornea were confirmed by Q-PCR and further characterized. HCEC transfection with h-miR-146a or h-miR-424 significantly retarded wound closure, but their respective antagomirs significantly enhanced wound healing vs. controls. Cells treated with h-miR-146a or h-miR-424 had decreased p-p38 and p-EGFR staining, but these increased over control levels close to the wound edge upon antagomir treatment. In conclusion, several miRNAs with increased expression in human diabetic central corneas were found. Two such miRNAs inhibited cultured corneal epithelial cell wound healing. Dysregulation of miRNA expression in human diabetic cornea may be an important mediator of abnormal wound healing.
Project description:The corneal epithelium is maintained by limbal epithelial stem cells (LESCs) and are largely responsible for corneal optical transparency and protection by continuous population of corneal epithelial cells. Diabetes mellitus (DM) has been shown to affect all structures of the eye including the cornea which can result in delayed wound healing and potential vision loss. MicroRNAs (miRNAs) are short non-coding oligonucleotides that regulate various cellular functions, including oxidative stress response, by repressing translation. miR-10b-5p was previously identified to be upregulated in diabetic vs. non-diabetic limbal cells and our purpose was to understand the role of miR-10b-5p in human limbal epithelial cells in normal and pathological conditions such as diabetes mellitus. It was hypothesized that miR-10b-5p influences corneal epithelial homeostasis by modulating antioxidant defenses and wound healing processes. Through integrated transcriptomic and proteomic analyses, we identified GCLM and LANCL1 as key miR-10b-5p targets, revealing its profound impact on glutathione metabolism, sulfur compound biosynthesis processes, and antioxidant defenses. Our finding suggests that miR-10b suppression disrupts redox balance which potentially leads to heightened oxidative stress, impaired wound healing and increased cellular vulnerability in diabetic corneas. Further research into miR-10b inhibitors or gene modulation strategies may pave the way for novel treatments aimed at mitigating oxidative stress-related corneal dysfunction, particularly in diabetes-induced ocular diseases.
Project description:MicroRNAs (miRNAs) are small, stable non-coding RNA molecules with regulatory function and marked tissue specificity that post-transcriptionally regulate gene expression, however their role in fungal keratitis remain unknown. Our purpose was to identify the miRNAs in human cornea from fungal keratitis patients and understand their key role in regulation of pathogenesis. Corneal samples from normal cadaver (n=3) and fungal keratitis (n=5) patients were pooled separately and total RNA was extracted. Deep sequencing was done using Illumina HiSeq1000 platform to identify miRNA profile. We identified seventy five differentially expressed miRNAs in fungal keratitis corneas. Select miRNAs were validated by real-time RT-PCR (Q-PCR). We predicted their role in regulating target genes in several pathways by combining miRNA target genes and pathway analysis, and mRNA expression of select target genes were further analysed by Q-PCR. MiR-21-5p, miR-223-3p, miR-146b-5p, miR-155-5p, miR-511-5p were found to be involved in inflammatory and immune responses, regulating Toll like receptor signaling pathways, which is of particular interest. MiR-451a with an increased expression in keratitis may have a role in wound healing by targeting Macrophage Migration Inhibitory Factor (MIF). Further, we highlighted that Neurotrophin signaling pathway may play a role in wound healing process. One novel miRNA was also detected in cornea. In conclusion, several miRNAs with high expression in fungal keratitis corneas point towards their role in regulation of pathogenesis. Further insights in understanding miRNAs role in wound healing and inflammation may help design new therapeutic strategies. Control and fungal keratitis, human corneal miRNA profiles were generated using IlluminaHiseq1000 platform
Project description:The corneal epithelium is maintained by limbal epithelial stem cells (LESCs) and is largely responsible for corneal optical transparency and protection by continuously renewing population of corneal epithelial cells. Diabetes mellitus (DM) affects all structures of the eye including the cornea, which can result in delayed wound healing and potential vision loss. MicroRNAs (miRNAs) are short non-coding oligonucleotides that regulate various cellular functions, including oxidative stress response, by repressing protein translation. MiR-10b-5p was previously identified to be upregulated in diabetic vs. non-diabetic limbal cells, and our purpose was to understand the role of miR-10b-5p in human limbal epithelial cells in healthy and diabetic conditions. Through integrated transcriptomic and proteomic analyses, we identified GCLM and LANCL1 as key miR-10b-5p targets, revealing its profound impact on glutathione metabolism, sulfur compound biosynthesis processes, and antioxidant defenses. Our findings suggest that overexpression of miR-10b disrupts redox balance, which potentially leads to heightened oxidative stress and increased cellular vulnerability in diabetic corneas. Understanding miR-10b function in corneal epithelial cells may pave the way for novel therapeutic strategies to mitigate oxidative stress and normalize corneal health in diabetic patients.
Project description:Diabetic foot ulcer (DFU) is a serious complication of diabetes mellitus, which causes great health damage and economic burden to patients. The pathogenesis of DFU is not fully understood.We screened wound healing-related genes using bioinformatics analysis, and full-thickness skin injury mice model and cellular assays were used to explore the role of target genes in diabetic wound healing. SFRP2 was identified as a wound healing-related gene, and the expression of SFRP2 is associated with immune cell infiltration in DFU. In vivo study showed that suppression of SFRP2 delayed the wound healing process of diabetic mice, impeded angiogenesis and matrix remodeling, and increased macrophage infiltration in wound tissues. In addition, suppression of SFRP2 enhanced M1 polarization in both the early and later stage of wound healing, and decreased M2 polarization in the later stage, which impeded the transition of M1 to M2 polarization of wound healing. Moreover, suppression of SFRP2 affected the transcriptome signatures-related to inflammatory response and energy metabolism at the early stage of wound healing. Extracellular flux analysis (EFA) showed that suppression of SFRP2 decreased mitochondrial energy metabolism and increased glycolysis in injury-related macrophages. Furthermore, suppression of SFRP2 inhibited transcriptome signaturesrelated to carbohydrate metabolism, lipid metabolism and amino acid metabolism, which consists the three main components of energy metabolism of macrophages. In conclusions, SFRP2 may function as a wound healing-related gene in DFU, and suppression of SFRP2 impaired diabetic wound healing by compromising the M1-to-M2 transition of macrophages and modulating the balance between mitochondrial energy metabolism and glycolysis.
Project description:Diabetic foot ulcer (DFU) is a serious complication of diabetes mellitus, which causes great health damage and economic burden to patients. The pathogenesis of DFU is not fully understood.We screened wound healing-related genes using bioinformatics analysis, and full-thickness skin injury mice model and cellular assays were used to explore the role of target genes in diabetic wound healing. SFRP2 was identified as a wound healing-related gene, and the expression of SFRP2 is associated with immune cell infiltration in DFU. In vivo study showed that suppression of SFRP2 delayed the wound healing process of diabetic mice, impeded angiogenesis and matrix remodeling, and increased macrophage infiltration in wound tissues. In addition, suppression of SFRP2 enhanced M1 polarization in both the early and later stage of wound healing, and decreased M2 polarization in the later stage, which impeded the transition of M1 to M2 polarization of wound healing. Moreover, suppression of SFRP2 affected the transcriptome signatures-related to inflammatory response and energy metabolism at the early stage of wound healing. Extracellular flux analysis (EFA) showed that suppression of SFRP2 decreased mitochondrial energy metabolism and increased glycolysis in injury-related macrophages. Furthermore, suppression of SFRP2 inhibited transcriptome signaturesrelated to carbohydrate metabolism, lipid metabolism and amino acid metabolism, which consists the three main components of energy metabolism of macrophages. In conclusions, SFRP2 may function as a wound healing-related gene in DFU, and suppression of SFRP2 impaired diabetic wound healing by compromising the M1-to-M2 transition of macrophages and modulating the balance between mitochondrial energy metabolism and glycolysis.
Project description:Impaired healing of diabetic wounds causes significant morbidity and mortality. This study aimed to identify novel mechanisms of diabetic wound healing defects and test a therapeutic intervention using diabetic mouse and pig models. We found Smad7 transgene expression in mouse epidermis promoting wound healing in diabetic dbdb mice, with reductions in obesity and blood glucose. To isolate effects of Smad7 on wounds, we created a Smad7-based biologic (Tat-PYC-Smad7) that penetrates wound cells. Topical application of Tat-PYC-Smad7 to diabetic pig and mouse wounds accelerated healing compared to controls. RNAseq analysis of mouse wound samples showed reduced TGF/NFB signaling, leading to faster re-epithelialization and better extracellular matrix remodeling. Tat-PYC-Smad7 also attenuated neutrophil degranulation and NETosis by blocking histone 3 citrullination and inhibiting myeloperoxidase activities. Our study reveals that Tat-PYC-Smad7 promotes diabetic wound healing by targeting keratinocytes and neutrophils, providing insight into cellular mechanisms of diabetic wound healing defects targetable by Smad7-based therapy.
Project description:Corneal injuries remain a major cause of consultation in the ophthalmology clinics worldwide. Repair of corneal wounds is a complex mechanism that involves cell death, migration, proliferation, differentiation, and extracellular matrix (ECM) remodeling. In the present study, we used a tissue-engineered, two-layers (epithelium and stroma) human cornea as a biomaterial to study both the cellular and molecular mechanisms of wound healing. Gene profiling on microarrays revealed important alterations in the pattern of genes expressed by tissue-engineered corneas in response to wound healing. Expression of many MMPs-encoding genes was shown by microarray and qPCR analyses to increase in the migrating epithelium of wounded corneas. Many of these enzymes were converted into their enzymatically active form as wound closure proceeded. In addition, expression of MMPs by human corneal epithelial cells (HCECs) was affected both by the stromal fibroblasts and the collagen-enriched ECM they produce. Most of all, results from mass spectrometry analyses provided evidence that a fully stratified epithelium is required for proper synthesis and organization of the ECM on which the epithelial cells adhere. In conclusion, and because of the many characteristics it shares with the native cornea, this human two layers corneal substitute may prove particularly useful to decipher the mechanistic details of corneal wound healing. Primary cultures of human corneal epithelial cells cultivated on BSA (number of replicates: 7), Collagen type I (number of replicates: 2), Collagen type IV (number of replicates: 2), Fibronectin (number of replicates: 2), Tenascin C (number of replicates: 2) and Laminin (number of replicates: 2) matrix. Central, internal and external ring of wounded Tissue-engineered human cornea.
Project description:At present, there is no effective treatment for diabetic wounds, and the cost of treatment is high. MicroRNAs (miRNAs) plays an important role in the process of diabetic wound healing. By regulating the expression of target genes, it regulates growth factors, cytokines and signal pathways, thereby affecting various stages of ulcer healing such as hemostasis, anti-inflammatory, proliferation and remodeling. In this study, differential expression of miRNAs in diabetic wound was screened. MiR-206 was selected as the research object to detect the effect of miR-206 on the proliferation of fibroblasts and vascular endothelial cell by regulating HIF-1?. Finally, in vivo studies showed that miR-206 antagomir could promote the expression of HIF-1?, CD34 and VEGF, and further promote wound healing in diabetic rats.