58 research outputs found
Ankyrin repeat and Single KH domain 1 (ANKHD1) drives renal cancer cell proliferation via binding to and altering a subset of miRNAs
Clear cell Renal Cell Carcinoma (ccRCC) represents the most common kidney cancer worldwide. Increased cell proliferation associated with abnormal microRNA (miRNA) regulation are hallmarks of carcinogenesis. Ankyrin repeat and single KH domain 1 (ANKHD1) is a highly conserved protein found to interact with core cancer pathways in Drosophila, however its involvement in RCC is completely unexplored. Quantitative PCR studies coupled with large-scale genomics data analyses demonstrated that ANKHD1 is significantly upregulated in kidneys of RCC patients when compared to healthy controls. Cell cycle analyses revealed that ANKHD1 is an essential factor for RCC cell division. To understand the molecular mechanism(s) utilized by ANKHD1 to drive RCC cell proliferation we performed bioinformatics analyses which revealed that ANKHD1 contains a putative miRNA-binding motif. We screened 48 miRNAs with tumour-enhancing or suppressing activities, and found that ANKHD1 binds to and regulates three tumour-suppressing miRNAs (i.e. miR-29a, miR-205, and miR-196a). RNA-immunoprecipitation assays demonstrated that ANKHD1 physically interacts with its target miRNAs via a single K-Homology (KH)-domain, located in the c-terminus of the protein. Functionally we discovered that ANKHD1 positively drives ccRCC cell mitosis via binding to and suppressing mainly miR-29a and to a lesser degree via miR-196a/205, leading to an upregulation in pro-proliferative genes such as CCDN1. Collectively, these data identify ANKHD1 as a new regulator of ccRCC proliferation via specific miRNA interactions
The controversial role of fibrosis in Autosomal Dominant Polycystic Kidney Disease
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is characterized by the progressive growth of cysts but it is also accompanied by diffuse tissue scarring or fibrosis. A number of recent studies have been published in this area, yet the role of fibrosis in ADPKD remains controversial. Here, we will discuss the stages of fibrosis progression in ADPKD, and how these compare with other common kidney diseases. We will also provide a detailed overview of some key mechanistic pathways to fibrosis in the polycystic kidney. Specifically, the role of the ‘chronic hypoxia hypothesis’, persistent inflammation, Transforming Growth Factor beta (TGFβ), Janus Kinase/Signal Transducers and Activators of Transcription (JAK/STAT) and microRNAs will be examined. Evidence for and against a pathogenic role of extracellular matrix during ADPKD disease progression will be provided
Renal expression of JAK2 is high in polycystic kidney disease and its inhibition reduces cystogenesis.
Autosomal dominant polycystic kidney disease (ADPKD) is the most common renal genetic disorder, however it still lacks a cure. The discovery of new therapies heavily depends on understanding key signalling pathways that lead to ADPKD. The JAnus Kinase and Signal Transducers and Activators of Transcription (JAK/STAT) pathway is aberrantly activated and contributes to ADPKD pathogenesis via enhancing epithelial proliferation. Yet the mechanisms underlying the upregulation of JAK/STAT activity in this disease context is completely unknown. Here, we investigate the role of JAK2 in ADPKD using a murine model of ADPKD (Pkd1nl/nl). In normal kidneys, JAK2 expression is limited to tubular epithelial and vascular cells with lesser staining in bowman's capsule and remains below detection level in the interstitium. By contrast, in kidneys of mice with ADPKD, JAK2 is higher in cyst-lining cells when compared to normal tubules and critically, it is ectopically expressed in the interstitium, suggesting that ectopic JAK2 may contribute to ADPKD. JAK2 activity was inhibited using either curcumin, a natural compound with strong JAK2 inhibitor activity, or Tofacitinib, a clinically used selective JAK small molecule inhibitor. JAK2 inhibition led to significantly reduced tyrosine phosphorylation of STAT3 and markedly reduced cystic growth of human and mouse ADPKD-derived cells in cystogenesis assays. Taken together, our results indicate that blockade of JAK2 shows promise as a novel therapeutic target in ADPKD
Data on CUX1 isoforms in idiopathic pulmonary fibrosis lung and systemic sclerosis skin tissue sections
This data article contains complementary figures related to the
research article entitled, “Transforming growth factor-β-induced
CUX1 isoforms are associated with fibrosis in systemic sclerosis
lung fibroblasts” (Ikeda et al. (2016) [2], http://dx.doi.org/10.1016/j.
bbrep.2016.06.022), which presents that TGF-β increased CUX1
binding in the proximal promoter and enhancer of the COL1A2 and
regulated COL1. Further, in the scleroderma (SSc) lung and diffuse
alveolar damage lung sections, CUX1 localized within the α-
smooth muscle actin (α-SMA) positive cells (Fragiadaki et al., 2011)
[1], “High doses of TGF-beta potently suppress type I collagen via
the transcription factor CUX1” (Ikeda et al., 2016) [2]. Here we
show that CUX1 isoforms are localized within α-smooth muscle
actin-positive cells in SSc skin and idiopathic pulmonary fibrosis
(IPF) lung tissue sections. In particular, at the granular and prickle
cell layers in the SSc skin sections, CUX1 and α-SMA are colocalized.
In addition, at the fibrotic loci in the IPF lung tissue
sections, CUX1 localized within the α-smooth muscle actin (α-
SMA) positive cells
Endothelial dysfunction in COVID-19: a position paper of the ESC Working Group for Atherosclerosis and Vascular Biology, and the ESC Council of Basic Cardiovascular Science
The COVID-19 pandemic is an unprecedented healthcare emergency causing mortality and illness across the world. Although primarily affecting the lungs, the SARS-CoV-2 virus also affects the cardiovascular system. In addition to cardiac effects, e.g. myocarditis, arrhythmias, and myocardial damage, the vasculature is affected in COVID-19, both directly by the SARS-CoV-2 virus, and indirectly as a result of a systemic inflammatory cytokine storm. This includes the role of the vascular endothelium in the recruitment of inflammatory leucocytes where they contribute to tissue damage and cytokine release, which are key drivers of acute respiratory distress syndrome (ARDS), in disseminated intravascular coagulation, and cardiovascular complications in COVID-19. There is also evidence linking endothelial cells (ECs) to SARS-CoV-2 infection including: (i) the expression and function of its receptor angiotensin-converting enzyme 2 (ACE2) in the vasculature; (ii) the prevalence of a Kawasaki disease-like syndrome (vasculitis) in COVID-19; and (iii) evidence of EC infection with SARS-CoV-2 in patients with fatal COVID-19. Here, the Working Group on Atherosclerosis and Vascular Biology together with the Council of Basic Cardiovascular Science of the European Society of Cardiology provide a Position Statement on the importance of the endothelium in the underlying pathophysiology behind the clinical presentation in COVID-19 and identify key questions for future research to address. We propose that endothelial biomarkers and tests of function (e.g. flow-mediated dilatation) should be evaluated for their usefulness in the risk stratification of COVID-19 patients. A better understanding of the effects of SARS-CoV-2 on endothelial biology in both the micro- and macrovasculature is required, and endothelial function testing should be considered in the follow-up of convalescent COVID-19 patients for early detection of long-term cardiovascular complications
Mechanical Activation of Hypoxia-Inducible Factor 1α Drives Endothelial Dysfunction at Atheroprone Sites
OBJECTIVE: Atherosclerosis develops near branches and bends of arteries that are exposed to low shear stress (mechanical drag). These sites are characterized by excessive endothelial cell (EC) proliferation and inflammation that promote lesion initiation. The transcription factor HIF1α (hypoxia-inducible factor 1α) is canonically activated by hypoxia and has a role in plaque neovascularization. We studied the influence of shear stress on HIF1α activation and the contribution of this noncanonical pathway to lesion initiation. APPROACH AND RESULTS: Quantitative polymerase chain reaction and en face staining revealed that HIF1α was expressed preferentially at low shear stress regions of porcine and murine arteries. Low shear stress induced HIF1α in cultured EC in the presence of atmospheric oxygen. The mechanism involves the transcription factor nuclear factor-κB that induced HIF1α transcripts and induction of the deubiquitinating enzyme Cezanne that stabilized HIF1α protein. Gene silencing revealed that HIF1α enhanced proliferation and inflammatory activation in EC exposed to low shear stress via induction of glycolysis enzymes. We validated this observation by imposing low shear stress in murine carotid arteries (partial ligation) that upregulated the expression of HIF1α, glycolysis enzymes, and inflammatory genes and enhanced EC proliferation. EC-specific genetic deletion of HIF1α in hypercholesterolemic apolipoprotein E-defecient mice reduced inflammation and endothelial proliferation in partially ligated arteries, indicating that HIF1α drives inflammation and vascular dysfunction at low shear stress regions. CONCLUSIONS: Mechanical low shear stress activates HIF1α at atheroprone regions of arteries via nuclear factor-κB and Cezanne. HIF1α promotes atherosclerosis initiation at these sites by inducing excessive EC proliferation and inflammation via the induction of glycolysis enzymes
Design, synthesis and antiparasitic evaluation of click phospholipids
A library of seventeen novel ether phospholipid analogues, containing 5-membered heterocyclic rings (1,2,3-triazolyl, isoxazolyl, 1,3,4-oxadiazolyl and 1,2,4-oxadiazolyl) in the lipid portion were designed and synthesized aiming to identify optimised miltefosine analogues. The compounds were evaluated for their in vitro antiparasitic activity against Leishmania infantum and Leishmania donovani intracellular amastigotes, against Trypanosoma brucei brucei and against different developmental stages of Trypanosoma cruzi. The nature of the substituents of the heterocyclic ring (tail) and the oligomethylene spacer between the head group and the heterocyclic ring was found to affect the activity and toxicity of these compounds leading to a significantly improved understanding of their structure\u2013activity relationships. The early ADMET profile of the new derivatives did not reveal major liabilities for the potent compounds. The 1,2,3-triazole derivative 27 substituted by a decyl tail, an undecyl spacer and a choline head group exhibited broad spectrum antiparasitic activity. It possessed low micromolar activity against the intracellular amastigotes of two L. infantum strains and T. cruzi Y strain epimastigotes, intracellular amastigotes and trypomastigotes, while its cytotoxicity concentration (CC50) against THP-1 macrophages ranged between 50 and 100 \ub5M. Altogether, our work paves the way for the development of improved ether phospholipid derivatives to control neglected tropical diseases
Snail1 factor behaves as a therapeutic target in renal fibrosis.
Kidney fibrosis is a devastating disease that leads to organ failure, and no
specific treatment is available to preserve organ function. In fibrosis,
myofibroblasts accumulate in the interstitium leading to massive
deposition of extracellular matrix and organ disfunction. The origin of
myofibroblasts is multiple and the contribution of renal epithelial cells
after undergoing epithelial-to-mesenchymal transition (EMT) is still
debated. In a model unable to reactivate the EMT inducer Snail1 upon
damage, we show that Snail1 is required in renal epithelial cells for the
development of fibrosis. Damage-mediated Snail1 reactivation induces a
partial EMT that relays fibrotic and inflammatory signals to the interstitium
through the activation of TGF-β and NF-B pathways. Snail1-induced
fibrosis can be reverted in vivo and inhibiting Snail1 in a model of
obstructive nephropathy highly ameliorates fibrosis. These results
reconcile conflicting data on the role of EMT in renal fibrosis and provide
avenues for the design of antifibrotic therapies.pre-print8435 K
Synthesis of new oxytocin analogues with high antagonistic activity
The synthesis of new OT analogues bearing the following modifications: L-ŕ-t-butylglycine [Gly(Bu')] at positions 8 and 9, D-Cys and D-Tyr(Et) at positions 6 and 2, respectively, and Mpa or Pen at position 1 have been described
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