Modulation of cardiac muscle contractility by phosphorylation, HCM and DCM causing mutations and small molecules

Mutations in sarcomeric proteins that cause familial hypertrophic cardiomyopathy and dilated cardiomyopathy have been shown to abolish the coupled relationship between troponin I phosphorylation and myofilament Ca2+-sensitivity, a phenomenon referred to as uncoupling. In normal heart, PKA phosphorylation of troponin I Ser22 and 23 leads to a 2-fold decrease in Ca2+-sensitivity and a corresponding increase in the rate of Ca2+ release from TnC and is essential for the lusitropic response to adrenergic stimulation. Therefore, uncoupling results in a blunted response to β1-adrenergic activation and has been demonstrated in animal models with hypertrophic cardiomyopathy and dilated cardiomyopathy mutations at a cellular, tissue and whole animal level. However, the molecular mechanisms and physiological relevance of uncoupling as a common phenomenon in cardiomyopathy-associated sarcomeric mutations are not well-understood. In this study, I have employed a multidisciplinary approach to probe for the presence of troponin uncoupling in mutation-containing cardiomyopathy models at an atomistic, molecular and cellular level. I have employed molecular dynamics simulation to elucidate how the structure and dynamics of troponin can give rise to physiological properties of cardiomyopathy. Additionally, I have investigated small molecules analogues of EGCG and silybin for recoupling properties that can restore the abolished relationship between troponin I phosphorylation and myofilament Ca2+-sensitivity in vitro, identifying a number of promising recoupling agents via in vitro motility assay. Moreover, I have demonstrated uncoupling at the cellular level as a blunting of the time to relaxation in intact cardiomyocytes following β-adrenergic stimulation and have developed a methodology that is capable of distinguishing cellularly-active recoupling molecules from candidates that are toxic. I have identified two promising recoupling agents, silybin B and resveratrol, using the contractile study presented herein, demonstrated by a reversal of the blunted phenotype. My investigation has demonstrated the feasibility of small molecules as recoupling agents and their therapeutic potential.Open Acces

Rethinking the UK languages curriculum:arguments for the inclusion of linguistics

This paper argues for a place for linguistics within the UK Modern Languages curriculum as part of a more pluralistic approach to languages study. Based on an intervention involving over 300 A-level students of French, German and Spanish, we demonstrate: 1) that it is feasible and appropriate to include linguistics topics on the A-level Modern Foreign Languages (MFL) curriculum; 2) that many of these topics are inherently interesting for A-level language students; and 3) that pupils report increased confidence in their language skills after having been exposed to a short linguistics course (four hours). In light of our further finding that there is already considerable untapped scope for linguistics within the current formal framework of the A-level MFL qualification, we recommend that linguistics topics should be included in MFL A-levels as a matter of priority. This is the case not least because linguistics has the potential to attract new pupils to the study of MFL, while also providing a crucial bridge between language skills and cultural content, which are so often kept apart in existing MFL curricula. Lastly, we argue that the introduction of linguistics into languages teaching raises awareness of the harmfulness of deeply entrenched prescriptive and standard-language-ideological beliefs in schools, and this will lead to a more inclusive discipline

Teacher perspectives on the introduction of linguistics in the languages classroom. Evidence from a co-creation project on French, German and Spanish

Linguistics is conspicuously absent from language teaching in UK schools. A-level cultural topics cover a range of themes such as cyber-society, cultural heritage and multiculturalism, but the approach taken to these topics is not informed by linguistics. In previous work, we have argued that this is an unfortunate omission not only because linguistics is appealing to many language students and perceived by them to be useful, but also because the existing cultural topics could be significantly enriched by the inclusion of the critical/analytical study of language itself. In this paper, we provide concrete examples of how linguistics can be integrated into the existing A-level curriculum for Modern Foreign Languages (MFL) in England and Wales. Reporting on a project in which teachers trialled linguistics materials co-created by us (a group of academics) and experienced languages teachers, we present evidence that linguistics materials are perceived to be both highly novel and nonetheless compatible with the existing A-level curriculum. Data from questionnaires and semi-structured interviews with participating teachers also show that: (i) these new materials can be taught with little or no prior experience of linguistics; and (ii) adding linguistics materials to the curriculum leads to significant impacts on teacher and pupil attitudes towards language(s). Despite some challenges, which we also discuss, the results highlight again the great potential of linguistics as a component of language teaching and the contribution that it can make to the enrichment of the discipline. (DIPF/Orig.

Molecular Defects in Cardiac Myofilament Ca2+-Regulation Due to Cardiomyopathy-Linked Mutations Can Be Reversed by Small Molecules Binding to Troponin

The inherited cardiomyopathies, hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM) are relatively common, potentially life-threatening and currently untreatable. Mutations are often in the contractile proteins of cardiac muscle and cause abnormal Ca2+ regulation via troponin. HCM is usually linked to higher myofilament Ca2+-sensitivity whilst in both HCM and DCM mutant tissue there is often an uncoupling of the relationship between troponin I (TnI) phosphorylation by PKA and modulation of myofilament Ca2+-sensitivity, essential for normal responses to adrenaline. The adrenergic response is blunted, and this may predispose the heart to failure under stress. At present there are no compounds or interventions that can prevent or treat sarcomere cardiomyopathies. There is a need for novel therapies that act at a more fundamental level to affect the disease process. We demonstrated that epigallocatechin-3 gallate (EGCG) was found to be capable of restoring the coupled relationship between Ca2+-sensitivity and TnI phosphorylation in mutant thin filaments to normal in vitro, independent of the mutation (15 mutations tested). We have labeled this property “re-coupling.” The action of EGCG in vitro to reverse the abnormality caused by myopathic mutations would appear to be an ideal pharmaceutical profile for treatment of inherited HCM and DCM but EGCG is known to be promiscuous in vivo and is thus unsuitable as a therapeutic drug. We therefore investigated whether other structurally related compounds can re-couple myofilaments without these off-target effects. We used the quantitative in vitro motility assay to screen 40 compounds, related to C-terminal Hsp90 inhibitors, and found 23 that can re-couple mutant myofilaments. There is no correlation between re-couplers and Hsp90 inhibitors. The Ca2+-sensitivity shift due to TnI phosphorylation was restored to 2.2 ± 0.01-fold (n = 19) compared to 2.0 ± 0.24-fold (n = 7) in wild-type thin filaments. Many of these compounds were either pure re-couplers or pure desensitizers, indicating these properties are independent; moreover, re-coupling ability could be lost with small changes of compound structure, indicating the possibility of specificity. Small molecules that can re-couple may have therapeutic potential. HIGHLIGHTS - Inherited cardiomyopathies are common diseases that are currently untreatable at a fundamental level and therefore finding a small molecule treatment is highly desirable. - We have identified a molecular level dysfunction common to nearly all mutations: uncoupling of the relationship between troponin I phosphorylation and modulation of myofilament Ca2+-sensitivity, essential for normal responses to adrenaline. - We have identified a new class of drugs that are capable of both reducing Ca2+-sensitivity and/or recouping the relationship between troponin I phosphorylation and Ca2+-sensitivity. - The re-coupling phenomenon can be explained on the basis of a single mechanism that is testable. - Measurements with a wide range of small molecules of varying structures can indicate the critical molecular features required for recoupling and allows the prediction of other potential re-couplers

Investigation of attentional bias in obsessive compulsive disorder with and without depression in visual search

Copyright: © 2013 Morein-Zamir et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedWhether Obsessive Compulsive Disorder (OCD) is associated with an increased attentional bias to emotive stimuli remains controversial. Additionally, it is unclear whether comorbid depression modulates abnormal emotional processing in OCD. This study examined attentional bias to OC-relevant scenes using a visual search task. Controls, non-depressed and depressed OCD patients searched for their personally selected positive images amongst their negative distractors, and vice versa. Whilst the OCD groups were slower than healthy individuals in rating the images, there were no group differences in the magnitude of negative bias to concern-related scenes. A second experiment employing a common set of images replicated the results on an additional sample of OCD patients. Although there was a larger bias to negative OC-related images without pre-exposure overall, no group differences in attentional bias were observed. However, OCD patients subsequently rated the images more slowly and more negatively, again suggesting post-attentional processing abnormalities. The results argue against a robust attentional bias in OCD patients, regardless of their depression status and speak to generalized difficulties disengaging from negative valence stimuli. Rather, post-attentional processing abnormalities may account for differences in emotional processing in OCD.Peer reviewedFinal Published versio

Ecological enhancement techniques to improve habitat heterogeneity on coastal defence structures

Sea level rise and higher storm frequency are increasing the need for the placement of hard coastal defences worldwide. The majority of these defences lack optimal habitats for intertidal species, resulting in low diversity and abundance. The construction of coastal defences within marine protected areas (MPA) is also increasing and this study investigates ways to limit the loss of species diversity and intertidal habitat caused by installing rock armour defence structures and other coastal developments. Arrays of holes and grooves were created on granite rock armour in the north of England at Runswick Bay, N. Yorkshire and limestone rock groynes in southern England at Boscombe, Poole Bay, Dorset. Runswick Bay is a Marine Conservation Zone (MCZ) designated for its intertidal habitat and Boscombe is located in close proximity to a Special Area of Conservation (SAC). After 12 months, the treatments had attracted new species to the defence structures and increased the overall diversity and abundance of organisms compared to control areas. Mobile fauna including crabs and fish were also recorded utilising the holes and grooves at Boscombe. Non-native species were recorded in grooves at one site however their abundance was not significantly different to that of control areas. At the southern site, species known to be spreading in response to climate change were found in treatments but not in control areas. The cost of the installation of these enhancement techniques was low in relation to that of the defence scheme and could be easily incorporated before, during or after construction. Through evaluation of the use of these ecological enhancement techniques on coastal structures, it is suggested that they have considerable potential to increase biodiversity on artificial structures, particularly when used within large-scale coastal engineering defence projects

Transcriptomics in Interferon-α-Treated Patients Identifies Inflammation-, Neuroplasticity- and Oxidative Stress-Related Signatures as Predictors and Correlates of Depression

Owing to the unique opportunity to assess individuals before and after they develop depression within a short timeframe, interferon-α (IFN-α) treatment for chronic hepatitis C virus (HCV) infection is an ideal model to identify molecular mechanisms relevant to major depression, especially in the context of enhanced inflammation. Fifty-eight patients were assessed prospectively, at baseline and monthly over 24 weeks of IFN-α treatment. New-onset cases of depression were determined using the Mini International Neuropsychiatric Interview (MINI). Whole-blood transcriptomic analyses were conducted to investigate the following: (1) baseline gene expression differences associated with future development of IFN-α-induced depression, before IFN-α, and (2) longitudinal gene expression changes from baseline to weeks 4 or 24 of IFN-α treatment, separately in those who did and did not develop depression. Transcriptomics data were analyzed using Partek Genomics Suite (1.4-fold, FDR adjusted pless than or equal to0.05) and Ingenuity Pathway Analysis Software. Twenty patients (34%) developed IFN-α-induced depression. At baseline, 73 genes were differentially expressed in patients who later developed depression compared with those who did not. After 4 weeks of IFN-α treatment, 592 genes were modulated in the whole sample, representing primarily IFN-α-responsive genes. Substantially more genes were modulated only in patients who developed depression (n=506, compared with n=70 in patients who did not), with enrichment in inflammation-, neuroplasticity- and oxidative stress-related pathways. A similar picture was observed at week 24. Our data indicate that patients who develop IFN-α-induced depression have an increased biological sensitivity to IFN-α, as shown by larger gene expression changes, and specific signatures both as predictors and as correlates