Investigating the Role of Epithelial-mesenchymal Crosstalk in the Pathology of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a disease of unknown aetiology, characterised by the progressive and irreversible scarring of parenchymal lung tissue that leads to respiratory failure and death. The disease is understood to be driven by an impaired and aberrant wound healing response, with an inappropriate reactivation of developmental signalling. The greatest risk factor for the disease is age, which is a process intimately associated with an increase in the burden of senescent cells. Such cells acquire a unique secretory phenotype and are known to have a significant impact on their local micro-environment. It was hypothesised that an alteration in epithelial-mesenchymal secretory communication, due to senescent-like changes in the fibroblast phenotype, may detrimentally contribute to lung homeostasis. An in vitro model of the lung airway was established in which primary human lung fibroblasts (HLFs) were co-cultured with human bronchial epithelial cells (HBECs). HBECs were cultured on a semi-permeable, transwell insert and co-cultured with either normal (NHLF), fibrotic (FHLF) or senescent fibroblasts. Over 72 hrs of co-culture, wound healing was assessed, via an epithelial scratch assay, and epithelial regeneration was measured, via trans-epithelial electrical resistance. Co-culture with NHLFs improves epithelial regeneration, however, FHLFs and senescent cells in co-culture show a diminished ability to promote epithelial regeneration and wound repair. The secretory repertoire of these cells contains elevated levels of IL-6, CXCL8, CXCL1 and GCSF (when assessed at both an RNA and protein level), factors strongly associated with the senescent phenotype. Targeting this secretome via treatment with the JAK 1/2 inhibitor Ruxolitinib attenuates these impairments and may point towards a new therapeutic strategy for the treatment of IPF

Characteristics of transplant athletes competing at national and international transplant games

OBJECTIVE: To describe the characteristics of athletes with solid-organ transplants (TxA) attending the British and World Transplant Games. METHODS: 220 TxA completed an online survey to explore transplant history, medications, training advice and support and limitations to training. RESULTS: TxA were predominantly caucasian, male, kidney recipients in their mid-forties and approximately 11 years post-transplant. The majority of TxA took some form of medication (immunosuppressants 88%, steroids 47%, antihypertensives 47%, statins 28%, antiplatelets 26%, antibiotics/antivirals/antifungals 20%). Stem cell recipients were least likely to require medication. Post-transplant complications were experienced by 40% of TxA, with 53% of these being rejection. Although over half the participants (57%) initially received exercise or training advice post-transplant, only 34% of these received this from their consultants or immediate medical team. Only 1% had been specifically directed towards transplant sport. Half of the TxA (53%) perceived there were limitations preventing them from performing at their potential, 45% considered they did not recover from training as well as non-TxA while 29% felt they trained equally to non-Tx’s. Only 6% considered medication impaired training. TxA competed for a range of reasons from social and health benefits to winning medals. CONCLUSIONS: TxA compete at the British and World Transplant Games for a diverse range of reasons. Athletes manage a range of medications with a range of exercise and health experiences pre-transplant. TxA face a lack of both general and specific exercise training and recovery guidance. The individuality of each TxA‘s background should be considered and is likely reflected in their exercise capacity and goals

Gully cut- and- fill cycles as related to agromanagement : a historical curve number simulation in the Tigray Highlands

Gully cut-and-fill dynamics are often thought to be driven by climate and/or deforestation related to population pressure. However, in this case-study of nine representative catchments in the Northern Ethiopian Highlands, we find that neither climate changes nor deforestation can explain gully morphology changes over the twentieth century. Firstly, by using a Monte Carlo simulation to estimate historical catchment-wide curve numbers, we show that the landscape was already heavily degraded in the nineteenth and early twentieth century – a period with low population density. The mean catchment-wide curve number (> 80) one century ago was, under the regional climatic conditions, already resulting in considerable simulated historical runoff responses. Secondly, twentieth century land-cover and runoff coefficient changes were confronted with twentieth century changing gully morphologies. As the results show, large-scale land-cover changes and deforestation cannot explain the observed processes. The study therefore invokes interactions between authigenic factors, small-scale plot boundary changes, cropland management and sociopolitical forces to explain the gully cut processes. Finally, semi-structured interviews and sedistratigraphic analysis of three filled gullies confirm the dominant impact of (crop)land management (tillage, check dams in gullies and channel diversions) on gully cut-and-fill processes. Since agricultural land management – including land tenure and land distribution – has been commonly neglected in earlier related research, we argue therefore that it can be a very strong driver of twentieth century gully morphodynamics

Differential expression of VEGF-Axxx isoforms is critical for development of pulmonary fibrosis

RATIONALE Fibrosis after lung injury is related to poor outcome, and idiopathic pulmonary fibrosis (IPF) can be regarded as an exemplar. Vascular endothelial growth factor (VEGF)-A has been implicated in this context, but there are conflicting reports as to whether it is a contributory or protective factor. Differential splicing of the VEGF-A gene produces multiple functional isoforms including VEGF-Aa and VEGF-Ab, a member of the inhibitory family. To date there is no clear information on the role of VEGF-A in IPF. OBJECTIVES To establish VEGF-A isoform expression and functional effects in IPF. METHODS We used tissue sections, plasma, and lung fibroblasts from patients with IPF and control subjects. In a bleomycin-induced lung fibrosis model we used wild-type MMTV mice and a triple transgenic mouse SPC-rtTATetoCreLoxP-VEGF-Ato conditionally induce VEGF-A isoform deletion specifically in the alveolar type II (ATII) cells of adult mice. MEASUREMENTS AND MAIN RESULTS IPF and normal lung fibroblasts differentially expressed and responded to VEGF-Aa and VEGF-Ab in terms of proliferation and matrix expression. Increased VEGF-Ab was detected in plasma of progressing patients with IPF. In a mouse model of pulmonary fibrosis, ATII-specific deficiency of VEGF-A or constitutive overexpression of VEGF-Ab inhibited the development of pulmonary fibrosis, as did treatment with intraperitoneal delivery of VEGF-Ab to wild-type mice. CONCLUSIONS These results indicate that changes in the bioavailability of VEGF-A sourced from ATII cells, namely the ratio of VEGF-Aa to VEGF-Ab, are critical in development of pulmonary fibrosis and may be a paradigm for the regulation of tissue repair

Basal body stability and ciliogenesis requires the conserved component Poc1

Centrioles are the foundation for centrosome and cilia formation. The biogenesis of centrioles is initiated by an assembly mechanism that first synthesizes the ninefold symmetrical cartwheel and subsequently leads to a stable cylindrical microtubule scaffold that is capable of withstanding microtubule-based forces generated by centrosomes and cilia. We report that the conserved WD40 repeat domain–containing cartwheel protein Poc1 is required for the structural maintenance of centrioles in Tetrahymena thermophila. Furthermore, human Poc1B is required for primary ciliogenesis, and in zebrafish, DrPoc1B knockdown causes ciliary defects and morphological phenotypes consistent with human ciliopathies. T. thermophila Poc1 exhibits a protein incorporation profile commonly associated with structural centriole components in which the majority of Poc1 is stably incorporated during new centriole assembly. A second dynamic population assembles throughout the cell cycle. Our experiments identify novel roles for Poc1 in centriole stability and ciliogenesis

'Ain't it a Ripping Night': Alcoholism and the Legacies of Empire in Salman Rushdie's Midnight's Children.

In the era of decolonisation that followed the Second World War, various authors sought to engage with India and the Empire’s past anew throughout their novels, identifying medicine and illness as key parts of Imperial authority and colonial experience. Salman Rushdie’s approach to the Raj in Midnight’s Children (1981) focused on the broad sweep of colonial life, juxtaposing the political and the personal. This article argues that Rushdie explores the history of colonial India by employing alcohol and alcoholism as lenses through which to explore the cultural, political and medical legacies of Empire. Through analysis of Midnight’s Children as well as a range of medical sources related to alcohol and inebriation, it will illustrate how drinking is central to Rushdie’s approach to secular and religious identities in newly independent India, as well as a means of satirising and undermining the supposed benefit that Empire presented to India and Indians

Adipose extracellular matrix remodelling in obesity and insulin resistance

The extracellular matrix (ECM) of adipose tissues undergoes constant remodelling to allow adipocytes and their precursor cells to change cell shape and function in adaptation to nutritional cues. Abnormal accumulation of ECM components and their modifiers in adipose tissues has been recently demonstrated to cause obesity-associated insulin resistance, a hallmark of type 2 diabetes. Integrins and other ECM receptors (e.g. CD44) that are expressed in adipose tissues have been shown to regulate insulin sensitivity. It is well understood that a hypoxic response is observed in adipose tissue expansion during obesity progression and that hypoxic response accelerates fibrosis and inflammation in white adipose tissues. The expansion of adipose tissues should require angiogenesis; however, the excess deposition of ECM limits the angiogenic response of white adipose tissues in obesity. While recent studies have focused on the metabolic consequences and the mechanisms of adipose tissue expansion and remodelling, little attention has been paid to the role played by the interaction between peri-adipocyte ECM and their cognate cell surface receptors. This review will address what is currently known about the roles played by adipose ECM, their modifiers, and ECM receptors in obesity and insulin resistance. Understanding how excess ECM deposition in the adipose tissue deteriorates insulin sensitivity would provide us hints to develop a new therapeutic strategy for the treatment of insulin resistance and type 2 diabetes

Potential responses to climate change in organisms with complex life histories: evolution and plasticity in Pacific salmon

Salmon life histories are finely tuned to local environmental conditions, which are intimately linked to climate. We summarize the likely impacts of climate change on the physical environment of salmon in the Pacific Northwest and discuss the potential evolutionary consequences of these changes, with particular reference to Columbia River Basin spring/summer Chinook (Oncorhynchus tshawytscha) and sockeye (Oncorhynchus nerka) salmon. We discuss the possible evolutionary responses in migration and spawning date egg and juvenile growth and development rates, thermal tolerance, and disease resistance. We know little about ocean migration pathways, so cannot confidently suggest the potential changes in this life stage. Climate change might produce conflicting selection pressures in different life stages, which will interact with plastic (i.e. nongenetic) changes in various ways. To clarify these interactions, we present a conceptual model of how changing environmental conditions shift phenotypic optima and, through plastic responses, phenotype distributions, affecting the force of selection. Our predictions are tentative because we lack data on the strength of selection, heritability, and ecological and genetic linkages among many of the traits discussed here. Despite the challenges involved in experimental manipulation of species with complex life histories, such research is essential for full appreciation of the biological effects of climate change