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This research examines the preferences and trade-offs of tenants during social housing retrofit programs, particularly in regard to implementing circular economy (CE) practices. The study looks beyond the relatively narrow consideration of energy efficiency, to respond to the broader requirements of the social housing sector—to incorporate and balance tenant needs with provider mandates, budgetary limitations, and wider social policy.Retrofitting, or upgrading, existing social housing stock has been proposed as a cost-efficient solution to concerns around energy efficiency, thermal performance, and quality issues.The research found that households’ preferences for housing retrofit and upgrade options did not necessarily align with evidence of optimal retrofit priorities and do not align with the typical activities which receive government funding. For example, commonly provided retrofit measures (such as draft sealing) were not widely valued, while less common interventions that were less focussed on energy efficiency (such as a deep clean) were highly regarded by consumer households.The objectives underlying retrofit programs are rarely explicit and vary greatly between stakeholders: social housing providers may be largely motivated to assist their tenants to avoid energy poverty; industry groups seem principally focussed on sustainability outcomes; and many tenants’ main motivation is wanting homes that are more liveable, efficient, clean and warm. These different, and often competing, objectives obviously limit successful outcomes. Retrofit and quality improvements that are undertaken with a short term focus, based on whatever funding or opportunities are available at that point in time, constrains all stakeholders from longer term planning or strategic coordination, but also reduces the opportunity to use CE principles in retrofit activities.

Vascular endothelial cell (EC) dysfunction plays a key role in diabetic complications. This study discovers significant upregulation of Quaking-7 (QKI-7) in iPS cell-derived ECs when exposed to hyperglycemia, and in human iPS-ECs from diabetic patients. QKI-7 is also highly expressed in human coronary arterial ECs from diabetic donors, and on blood vessels from diabetic critical limb ischemia patients undergoing a lower-limb amputation. QKI-7 expression is tightly controlled by RNA splicing factors CUG-BP and hnRNPM through direct binding. QKI-7 upregulation is correlated with disrupted cell barrier, compromised angiogenesis and enhanced monocyte adhesion. RNA immunoprecipitation (RIP) and mRNA-decay assays reveal that QKI-7 binds and promotes mRNA degradation of downstream targets CD144, Neuroligin 1 (NLGN1), and TNF-α-stimulated gene/protein 6 (TSG-6). When hindlimb ischemia is induced in diabetic mice and QKI-7 is knocked-down in vivo in ECs, reperfusion and blood flow recovery are markedly promoted. Manipulation of QKI-7 represents a promising strategy for the treatment of diabetic vascular complications., Vascular endothelial cell (EC) dysfunction contributes to the occurrence of diabetic complications. Here the authors report that in diabetic conditions, upregulation of the RNA binding protein QKI-7 in ECs due to the imbalance of RNA splicing factors CUG-BP and hnRNPM contributes to EC dysfunction, and that in vivo QKI-7 silencing improves blood flow recovery in diabetic mice with limb ischemia.

Dysfunction of endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) leads to ischaemia, the central pathology of cardiovascular disease. Stem cell technology will revolutionise regenerative medicine, but a need remains to understand key mechanisms of vascular differentiation. RNA-binding proteins have emerged as novel post-transcriptional regulators of alternative splicing and we have previously shown that the RNA-binding protein Quaking (QKI) plays roles in EC differentiation. In this study, we decipher the role of the alternative splicing isoform Quaking 6 (QKI-6) to induce VSMC differentiation from induced pluripotent stem cells (iPSCs). PDGF-BB stimulation induced QKI-6, which bound to HDAC7 intron 1 via the QKI-binding motif, promoting HDAC7 splicing and iPS-VSMC differentiation. Overexpression of QKI-6 transcriptionally activated SM22 (also known as TAGLN), while QKI-6 knockdown diminished differentiation capability. VSMCs overexpressing QKI-6 demonstrated greater contractile ability, and upon combination with iPS-ECs-overexpressing the alternative splicing isoform Quaking 5 (QKI-5), exhibited higher angiogenic potential

Dysfunction of endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) leads to ischaemia, the central pathology of cardiovascular disease. Stem cell technology will revolutionise regenerative medicine, but a need remains to understand key mechanisms of vascular differentiation. RNA-binding proteins have emerged as novel post-transcriptional regulators of alternative splicing and we have previously shown that the RNA-binding protein Quaking (QKI) plays roles in EC differentiation. In this study, we decipher the role of the alternative splicing isoform Quaking 6 (QKI-6) to induce VSMC differentiation from induced pluripotent stem cells (iPSCs). PDGF-BB stimulation induced QKI-6, which bound to HDAC7 intron 1 via the QKI-binding motif, promoting HDAC7 splicing and iPS-VSMC differentiation. Overexpression of QKI-6 transcriptionally activated SM22 (also known as TAGLN), while QKI-6 knockdown diminished differentiation capability. VSMCs overexpressing QKI-6 demonstrated greater contractile ability, and upon combination with iPS-ECs-overexpressing the alternative splicing isoform Quaking 5 (QKI-5), exhibited higher angiogenic potential in vivo than control cells alone. This study demonstrates that QKI-6 is critical for modulation of HDAC7 splicing, regulating phenotypically and functionally robust iPS-VSMCs. These findings also highlight that the QKI isoforms hold key roles in alternative splicing, giving rise to cells which can be used in vascular therapy or for disease modelling. This article has an associated First Person interview with the first author of the paper.

The mortality rate for (cardio)-vascular disease is one of the highest in the world, so a healthy functional endothelium is of outmost importance against vascular disease. In this study, human induced pluripotent stem (iPS) cells were reprogrammed from 1 ml blood of healthy donors and subsequently differentiated into endothelial cells (iPS-ECs) with typical EC characteristics. This research combined iPS cell technologies and next-generation sequencing to acquire an insight into the transcriptional regulation of iPS-ECs. We identified Endothelial cell-specific molecule 1 (ESM1) as one of the highest expressed genes during EC differentiation, playing a key role in EC enrichment and function by regulating connexin 40 (CX40) and eNOS. Importantly, ESM1 enhanced the iPS-ECs potential to improve angiogenesis and neovascularisation in in vivo models of angiogenesis and hind limb ischemia. These findings demonstrated for the first time that enriched functional ECs are derived through cell reprogramming and ESM1 signalling, opening the horizon for drug screening and cell-based therapies for vascular diseases. Therefore, this study showcases a new approach for enriching and enhancing the function of induced pluripotent stem (iPS) cell-derived endothelial cells from a very small amount of blood through ESM1 signalling, which greatly enhances their functionality and increases their therapeutic potential. © AlphaMed Press 2018.

Vascular endothelial cell (EC) dysfunction plays a key role in diabetic complications. This study discovers significant upregulation of Quaking-7 (QKI-7) in iPS cell-derived ECs when exposed to hyperglycemia, and in human iPS-ECs from diabetic patients. QKI-7 is also highly expressed in human coronary arterial ECs from diabetic donors, and on blood vessels from diabetic critical limb ischemia patients undergoing a lower-limb amputation. QKI-7 expression is tightly controlled by RNA splicing factors CUG-BP and hnRNPM through direct binding. QKI-7 upregulation is correlated with disrupted cell barrier, compromised angiogenesis and enhanced monocyte adhesion. RNA immunoprecipitation (RIP) and mRNA-decay assays reveal that QKI-7 binds and promotes mRNA degradation of downstream targets CD144, Neuroligin 1 (NLGN1), and TNF-α-stimulated gene/protein 6 (TSG-6). When hindlimb ischemia is induced in diabetic mice and QKI-7 is knocked-down in vivo in ECs, reperfusion and blood flow recovery are markedly promoted. Manipulation of QKI-7 represents a promising strategy for the treatment of diabetic vascular complications.

Cardiovascular disease (CVD) is the leading cause of death globally, in 2013 it was responsible for 30% of all deaths worldwide. It has been shown that endothelial dysfunction is a major pathological mechanism that precedes CVD, yet these damaged endothelial cells (ECs) display poor regenerative capabilities. Current therapy is inadequate or unsuitable for a significant number of patients, however it is thought that the ability to replace damaged ECs could serve as a valuable therapeutic option for the future. Recent capability to generate induced pluripotent stem cells (iPSCs) from adult cells and differentiate these towards ECs holds great promise in the area of regenerative medicine. Nevertheless, the differentiation process involved is complex and not fully understood. An appreciation of a variety of molecular mechanisms is required in order to enhance protocols that could be replicated for novel therapies. This project has derived ECs from iPSCs using a reliable protocol. Results here confirmed successful differentiation with an up-regulation in important endothelial markers at the mRNA level alongside positive immunofluorescent staining. These differentiated cells were characteristically similar to mature ECs. In order to expose underlying mechanisms of EC differentiation, the novel gene SETSIP was shown to be upregulated during this process. Further investigation to stimulate differentiating cells with a SETSIP peptide noted an induction in endothelial markers. Finally, experiments involving epigenetic drugs induced changes in both endothelial marker and SETSIP expression. This project has elucidated the role of SETSIP and data shown here may be important in advancing therapeutic potential through the development of more robust protocols concerning EC differentiation.

The fight against vascular disease requires functional endothelial cells (ECs) which could be provided by differentiation of induced Pluripotent Stem Cells (iPS Cells) in great numbers for use in the clinic. However, the great promise of the generated ECs (iPS‐ECs) in therapy is often restricted due to the challenge in iPS‐ECs preserving their phenotype and function. We identified that Follistatin‐Like 3 (FSTL3) is highly expressed in iPS‐ECs, and, as such, we sought to clarify its possible role in retaining and improving iPS‐ECs function and phenotype, which are crucial in increasing the cells’ potential as a therapeutic tool. We overexpressed FSTL3 in iPS‐ECs and found that FSTL3 could induce and enhance endothelial features by facilitating β‐catenin nuclear translocation through inhibition of glycogen synthase kinase‐3β activity and induction of Endothelin‐1. The angiogenic potential of FSTL3 was also confirmed both in vitro and in vivo. When iPS‐ECs overexpressing FSTL3 were subcutaneously injected in in vivo angiogenic model or intramuscularly injected in a hind limb ischemia NOD.CB17‐Prkdcscid/NcrCrl SCID mice model, FSTL3 significantly induced angiogenesis and blood flow recovery, respectively. This study, for the first time, demonstrates that FSTL3 can greatly enhance the function and maturity of iPS‐ECs. It advances our understanding of iPS‐ECs and identifies a novel pathway that can be applied in cell therapy. These findings could therefore help improve efficiency and generation of therapeutically relevant numbers of ECs for use in patient‐specific cell‐based therapies. In addition, it can be particularly useful toward the treatment of vascular diseases instigated by EC dysfunction. Stem Cells 2018;36:1033–1044

Atherosclerosis is the leading cause of death in the developed world and involves the production of an atherosclerotic plaque in the artery wall, limiting blood flow and resulting in conditions such as peripheral artery disease, coronary heart disease, myocardial infarction, and stroke. Autophagy is a method of self-digestion, primarily a survival pathway for the cell, to remove and/or recycle old and damaged proteins in the cytoplasm. There is increasing evidence that autophagy takes place in severe atherosclerotic plaques implicating macrophages and vascular smooth muscle cells. In addition, oxidized low-density lipoprotein (Ox-LDL) can also trigger autophagy in endothelial cells (ECs) through LC3β/BECLIN-1, leading to the lysosome-mediated degradation of Ox-LDL. However the role of autophagy in atherosclerosis still remains shrouded in mystery, as it is still debated whether autophagy is a damaging or a protective mechanism or a balance of both is needed for normal cellular function. X-Box binding protein 1 (XBP1) mRNA splicing is involved in the regulation of autophagy in ECs through BECLIN-1 transcriptional activation. It has recently been shown that sustained activation of XBP1 results in EC apoptosis and development of atherosclerosis. More evidence has shown the importance of XBP1 in eliciting an autophagic response in ECs. Therefore, it seems that the threshold of the autophagic responses could be determined through the tight regulation of the expression and duration of splicing activation of molecules, such as XBP1s, in a cell-specific manner.

The vascular endothelium is central to cardiovascular homeostasis. Repair and regeneration of endothelial cells (ECs) has been an important research focus for a number of years. The recent ability to derive ECs through cell reprogramming has opened new avenues. Reprogramming somatic cells to ECs is in its infancy, but the road ahead looks very promising. A new reprogramming strategy has ruled out safety issues concerned with teratoma formation. Cells exposed to reprogramming factors for 4 days become epigenetically primed and have been defined as Partially induced Pluripotent Stem (PiPS) cells. They do not transverse pluripotency, and so do not form tumours. They have shown the ability to be differentiated into ECs by culture conditions. Efficiency of reprogramming has increased from 0.01% to 30–40% in the case of PiPS-ECs, but there is scope for improvement as the underlying mechanisms are still unclear. The role of epigenetics in reprogramming has come to the forefront recently and the ability to generate a homogenous and functional EC population will be best sought through chromatin remodelling mechanisms. A protein found to be crucial in 4-day reprogramming was SETSIP, or SET similar protein. SETSIP has high sequence homology to SET with an additional 10 amino acids at the N-terminus. SET plays roles in chromatin remodelling as a transcriptional regulator and roles in differentiation, apoptosis and cell cycle progression. The study aims to elucidate a robust and efficient protocol for the production of a homogenous and functional EC population for use in personalised cardiovascular medicine. SETSIP has been overexpressed and knocked out of early PiPS-ECs and iPS-ECs to observe the effect on EC reprogramming. Luciferase assays have been undertaken to understand the EC specific pathways regulated by SETSIP. Experiments have also been performed to establish the effect of treatment with VEGF on SETSIP expression and EC differentiation. Future work will involve the employment of CRISPR technology to create a SETSIP deficient cell line to observe the differentiation potential of the cells and phenotype of any derived ECs. SETSIP was found to translocate to the cell nuclei, and capable of regulating expression of important EC markers. The functional consequences of this were assessed in vitro and in vivo where SETSIP was found to be important for the formation of vascular tubules. Furthermore, epigenetic modulators such as CBP/p300 were identified as potential mediators of the gene regulatory effects of SETSIP in ECs. These results represent an important step forward in understanding the process of EC reprogramming for use in regenerative medicine. These findings provide knowledge of the intricate processes during EC reprogramming not only to support the scientific validity of the newly generated ECs but also to ensure the safety of bringing cellular reprogramming to the bedside of cardiovascular patients.