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miRNA-21 is dysregulated in response to vein grafting in multiple models and genetic ablation in mice attenuates neointima formation.

McDonald RA, White KM, Wu J, Cooley BC, Robertson KE, Halliday CA, McClure JD, Francis S, Lu R, Kennedy S, George SJ, Wan S, van Rooij E, Baker AH - Eur. Heart J. (2013)

Bottom Line: Identifying novel strategies to prevent neointimal thickening is important.Thus, this study aimed to identify microRNAs (miRNAs) that are dysregulated during neointimal formation and determine their pathophysiological relevance following miRNA manipulation.Furthermore, pharmacological knockdown of miR-21 in human veins resulted in target gene de-repression and a significant reduction in neointimal formation.

View Article: PubMed Central - PubMed

Affiliation: Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8TA, UK.

ABSTRACT

Aims: The long-term failure of autologous saphenous vein bypass grafts due to neointimal thickening is a major clinical burden. Identifying novel strategies to prevent neointimal thickening is important. Thus, this study aimed to identify microRNAs (miRNAs) that are dysregulated during neointimal formation and determine their pathophysiological relevance following miRNA manipulation.

Methods and results: We undertook a microarray approach to identify dysregulated miRNAs following engraftment in an interpositional porcine graft model. These profiling experiments identified a number of miRNAs which were dysregulated following engraftment. miR-21 levels were substantially elevated following engraftment and these results were confirmed by quantitative real-time PCR in mouse, pig, and human models of vein graft neointimal formation. Genetic ablation of miR-21 in mice or grafted veins dramatically reduced neointimal formation in a mouse model of vein grafting. Furthermore, pharmacological knockdown of miR-21 in human veins resulted in target gene de-repression and a significant reduction in neointimal formation.

Conclusion: This is the first report demonstrating that miR-21 plays a pathological role in vein graft failure. Furthermore, we also provided evidence that knockdown of miR-21 has therapeutic potential for the prevention of pathological vein graft remodelling.

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Related in: MedlinePlus

Global microRNA profiling and assessment of miR-21 in vein grafting. (A) A schematic diagram illustrating how the samples were prepared for global microRNA expression, using microfluidic cards. Ungrafted saphenous veins were compared with veins subjected to vein grafting for a period of 7 and 28 days. We evaluated only targets which were >4-fold up-regulated at both time points. (B) A heat map of the only microRNAs which were significantly up-regulated >4-fold; the table summarizes the fold change, P-values, and the false discovery rate (FDR) for each microRNA. (C) Relative quantification of the miR-21 array results normalized to miR-199a-3p. (D) Verification of TLDA array by real-time-PCR, demonstrating up-regulation of miR-21 in porcine veins following grafting for 7 and 28 days (n = 6/group). (E) Expression of miR-21 in control ungrafted jugular vein (JV) and vein graft (VG) from mice (n = 5/group). (F) Real-time PCR for miR-21 expression in HSV subjected to culture for a period of 0, 7, 14, or 28 days to allow neointimal lesions to develop (n = 6/group). Error bars denote SEM; *P < 0.05, **P < 0.01. Data were analysed by one-way ANOVA with a Tukey's post-test.
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EHT105F1: Global microRNA profiling and assessment of miR-21 in vein grafting. (A) A schematic diagram illustrating how the samples were prepared for global microRNA expression, using microfluidic cards. Ungrafted saphenous veins were compared with veins subjected to vein grafting for a period of 7 and 28 days. We evaluated only targets which were >4-fold up-regulated at both time points. (B) A heat map of the only microRNAs which were significantly up-regulated >4-fold; the table summarizes the fold change, P-values, and the false discovery rate (FDR) for each microRNA. (C) Relative quantification of the miR-21 array results normalized to miR-199a-3p. (D) Verification of TLDA array by real-time-PCR, demonstrating up-regulation of miR-21 in porcine veins following grafting for 7 and 28 days (n = 6/group). (E) Expression of miR-21 in control ungrafted jugular vein (JV) and vein graft (VG) from mice (n = 5/group). (F) Real-time PCR for miR-21 expression in HSV subjected to culture for a period of 0, 7, 14, or 28 days to allow neointimal lesions to develop (n = 6/group). Error bars denote SEM; *P < 0.05, **P < 0.01. Data were analysed by one-way ANOVA with a Tukey's post-test.

Mentions: In order to identify aberrantly expressed miRNA during neointima formation in the setting of vein graft failure, we compared miRNA expression patterns by microarray analysis in ungrafted and grafted porcine SVs isolated 7 and 28 days post-engraftment (Figure 1A). Global miRNA profiling analysis revealed that 21 out of 377 miRNAs were up-regulated following engraftment (see Supplementary material online, Figure S1 and Table S1), 6 of which were up-regulated more than 4-fold (FDR < 0.1) at 7 and 28 days post-engraftment (Figure 1B). From this data set, we focused on miR-21 due to the substantial up-regulation observed in pig grafts compared with controls (Figure 1C) and since it has previously been implicated in SMC and fibroblast proliferation following acute vascular injury.25,26Figure 1


miRNA-21 is dysregulated in response to vein grafting in multiple models and genetic ablation in mice attenuates neointima formation.

McDonald RA, White KM, Wu J, Cooley BC, Robertson KE, Halliday CA, McClure JD, Francis S, Lu R, Kennedy S, George SJ, Wan S, van Rooij E, Baker AH - Eur. Heart J. (2013)

Global microRNA profiling and assessment of miR-21 in vein grafting. (A) A schematic diagram illustrating how the samples were prepared for global microRNA expression, using microfluidic cards. Ungrafted saphenous veins were compared with veins subjected to vein grafting for a period of 7 and 28 days. We evaluated only targets which were >4-fold up-regulated at both time points. (B) A heat map of the only microRNAs which were significantly up-regulated >4-fold; the table summarizes the fold change, P-values, and the false discovery rate (FDR) for each microRNA. (C) Relative quantification of the miR-21 array results normalized to miR-199a-3p. (D) Verification of TLDA array by real-time-PCR, demonstrating up-regulation of miR-21 in porcine veins following grafting for 7 and 28 days (n = 6/group). (E) Expression of miR-21 in control ungrafted jugular vein (JV) and vein graft (VG) from mice (n = 5/group). (F) Real-time PCR for miR-21 expression in HSV subjected to culture for a period of 0, 7, 14, or 28 days to allow neointimal lesions to develop (n = 6/group). Error bars denote SEM; *P < 0.05, **P < 0.01. Data were analysed by one-way ANOVA with a Tukey's post-test.
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Related In: Results  -  Collection

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EHT105F1: Global microRNA profiling and assessment of miR-21 in vein grafting. (A) A schematic diagram illustrating how the samples were prepared for global microRNA expression, using microfluidic cards. Ungrafted saphenous veins were compared with veins subjected to vein grafting for a period of 7 and 28 days. We evaluated only targets which were >4-fold up-regulated at both time points. (B) A heat map of the only microRNAs which were significantly up-regulated >4-fold; the table summarizes the fold change, P-values, and the false discovery rate (FDR) for each microRNA. (C) Relative quantification of the miR-21 array results normalized to miR-199a-3p. (D) Verification of TLDA array by real-time-PCR, demonstrating up-regulation of miR-21 in porcine veins following grafting for 7 and 28 days (n = 6/group). (E) Expression of miR-21 in control ungrafted jugular vein (JV) and vein graft (VG) from mice (n = 5/group). (F) Real-time PCR for miR-21 expression in HSV subjected to culture for a period of 0, 7, 14, or 28 days to allow neointimal lesions to develop (n = 6/group). Error bars denote SEM; *P < 0.05, **P < 0.01. Data were analysed by one-way ANOVA with a Tukey's post-test.
Mentions: In order to identify aberrantly expressed miRNA during neointima formation in the setting of vein graft failure, we compared miRNA expression patterns by microarray analysis in ungrafted and grafted porcine SVs isolated 7 and 28 days post-engraftment (Figure 1A). Global miRNA profiling analysis revealed that 21 out of 377 miRNAs were up-regulated following engraftment (see Supplementary material online, Figure S1 and Table S1), 6 of which were up-regulated more than 4-fold (FDR < 0.1) at 7 and 28 days post-engraftment (Figure 1B). From this data set, we focused on miR-21 due to the substantial up-regulation observed in pig grafts compared with controls (Figure 1C) and since it has previously been implicated in SMC and fibroblast proliferation following acute vascular injury.25,26Figure 1

Bottom Line: Identifying novel strategies to prevent neointimal thickening is important.Thus, this study aimed to identify microRNAs (miRNAs) that are dysregulated during neointimal formation and determine their pathophysiological relevance following miRNA manipulation.Furthermore, pharmacological knockdown of miR-21 in human veins resulted in target gene de-repression and a significant reduction in neointimal formation.

View Article: PubMed Central - PubMed

Affiliation: Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8TA, UK.

ABSTRACT

Aims: The long-term failure of autologous saphenous vein bypass grafts due to neointimal thickening is a major clinical burden. Identifying novel strategies to prevent neointimal thickening is important. Thus, this study aimed to identify microRNAs (miRNAs) that are dysregulated during neointimal formation and determine their pathophysiological relevance following miRNA manipulation.

Methods and results: We undertook a microarray approach to identify dysregulated miRNAs following engraftment in an interpositional porcine graft model. These profiling experiments identified a number of miRNAs which were dysregulated following engraftment. miR-21 levels were substantially elevated following engraftment and these results were confirmed by quantitative real-time PCR in mouse, pig, and human models of vein graft neointimal formation. Genetic ablation of miR-21 in mice or grafted veins dramatically reduced neointimal formation in a mouse model of vein grafting. Furthermore, pharmacological knockdown of miR-21 in human veins resulted in target gene de-repression and a significant reduction in neointimal formation.

Conclusion: This is the first report demonstrating that miR-21 plays a pathological role in vein graft failure. Furthermore, we also provided evidence that knockdown of miR-21 has therapeutic potential for the prevention of pathological vein graft remodelling.

Show MeSH
Related in: MedlinePlus