Genetic influence on cardiovascular reactivity

In a new study recently published in Psychosomatic Medicine, PredSL PI Harold Snieder and co-workers investigated the genetic and environmental architecture of blood pressure and underlying hemodynamics at rest and during stress in two ethnic groups. Cardiovascular measures obtained during both conditions showed substantial heritability indices that were comparable between individuals of African and European descent. Most of the variance in both resting and stress levels was found to be explained by common genetic factors, although other genetic factors that only contribute to cardiovascular levels during stress were also found to be important.

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Study Identifies New Gene Variations Associated With Heart Rate

New genetic variations associated with heart rate have been identified in a collaborative genome-wide study in which 268 researchers from 211 institutions, as well as six large research consortia joined forces. PredSL PI Harold Snieder contributed to this study. Since heart rate is a marker of cardiovascular health, researchers anticipated that a better understanding of its genetic regulation might provide a first step towards identifying targets for new drugs to treat cardiovascular disease. The study titled, “Identification of Heart Rate-Associated Loci and Their Effects on Cardiac Conduction and Rhythm Disorders,” was published online last week in the April issue of Nature Genetics.

To gain new insights into the genetic regulation of heart rate, the rseearchers spent three years working on a genome-wide association study using data from 181,171 participants from 65 studies during 2009-2012.  This effort resulted in the discovery of 14 new genetic variations that are associated with heart rate. Without any prior hypothesis, the entire human genome was studied, hoping to identify new genetic variations that no one before had even imagined would play a role in the regulation of heart rate. Experimental down-regulation of gene expression was then conducted on fruit flies and zebrafish, to better understand how genetic variations might affect heart rate. These experiments identified 20 genes with a role in heart rate regulation, signal transmission, embryonic development of the heart, as well cardiac disorders, such as dilated cardiomyopathy, congenital heart failure and sudden heart failure. The findings in humans as well as in fruit flies and zebrafish provide new insights into mechanisms that regulate heart rate.

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Natasha Maurits appointed visiting professor at Department of Bioengineering at Strathclyde University

Per January 1, 2013, Natasha Maurits has been appointed Visiting Professor at the Department of Bioengineering at Strathclyde University in Glasgow, UK, for a period of three years. Here, she will further expand her scientific collaboration with Prof. Bernard Conway and his group. Prof. Conway is an expert in the neuronal mechanisms that contribute to the generation and control of movement in humans and employs a variety of techniques (a.o. high density EEG data capture and analysis systems, haptic interfaces for hand and arm, virtual reality and multichannel EMG recording and analysis). In addition, Maurits will teach, conveying her knowledge on clinical neuroengineering to bioengineering students.

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Changes in DNA methylation in hypertension

On 11 jan 2013 a new paper from PredSL PI Harold Snieder and collaborators was published in the journal PLOS ONE entitled “A Genome-Wide Methylation Study on Essential Hypertension in Young African American Males. After Snieder’s group published the first epigenome-wide association study (EWAS) of obesity in 2010 this is now also the very first study of its kind investigating hypertension. They conclude that identification of a difference in a blood leukocyte DNA methylation site between hypertensive cases and normotensive controls suggests that changes in DNA methylation may play an important role in the pathogenesis of hypertension. The age dependency of the effect further suggests complexity of epigenetic regulation in this age-related disease.

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The Road Map for European Ageing Research: a source of inspiration for PredSL

Road mapThe Road Map for European Ageing Research was drafted last year by the FUTURAGE project and contains the research agenda that will enable Europe to respond successfully to the unprecedented demographic challenges it faces. The Road Map priority themes for future ageing research are all based on eight fundamental assumptions: multi-disciplinarity, user engagement, a life course perspective, a person-environment perspective, the importance of diversities and intergenerational relationships, knowledge exchange and technological innovation. PredSL links two Road Map priority themes: Maintaining and regaining mental capacity and Inclusion and participation in the community and in the labour market.

Cochrane review on interventions to facilitate return to work

PredSL PI Ute Bültmann contributed to a Cochrane Review on interventions to facilitate return to work in adults with adjustment disorders that was published today.

Adjustment disorders are a frequent cause of sick leave and various interventions have been developed to expedite the return to work (RTW) of individuals on sick leave due to adjustment disorders. The review assesses the effects of interventions facilitating RTW for workers with acute or chronic adjustment disorders and discusses results from nine studies reporting on 10 psychological interventions and one combined intervention in 1546 participants.

 

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Cortisol and anxiety and depressive problems – results from TRAILS

PredSL PI Catharina Hartman contributed to  a study – that was published today in Psychoneuroendocrinology – on the relationship between anxiety and depressive problems and hypothalamic-pituitary-adrenal (HPA)-axis activity (cortisol in the morning). The study was executed in children from the TRAILS study, a general population and clinic-referred cohort.

Anxiety and depressive problems have often been related to higher hypothalamic-pituitary-adrenal (HPA)-axis activity (basal morning cortisol levels and cortisol awakening response [CAR]) and externalizing problems to lower HPA-axis activity. However, associations appear weaker and more inconsistent than initially assumed. Previous studies from TRAILS suggested sex-differences in these relationships and differential associations with specific dimensions of depressive problems in a general population sample of children (10-12 years). Using the TRAILS population sample (n=1604), the authors found most support for higher cortisol (mainly CAR) in relation to depressive problems. However, in general, associations were weak. Therefore, the present results shed doubt on the relevance of single day cortisol measurements for problem behaviors in the milder range. Associations may be stronger in more severe or persistent psychopathology.

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On the threshold of disorder

Today, Julie Karsten defended her PhD thesis entitled ‘On the treshold of disorder. Definition and course of subthreshold depression and subthreshold anxiety’. She was supervised by PredSL PI Catharina Hartman, Brenda Penninx and Willem Nolen. Her thesis resulted in five published papers in high ranking journals.

Subthreshold depression and subthreshold anxiety are common and associated with increased impairment, subjective suffering, and economic costs. Furthermore, individuals
with subthreshold depression or subthreshold anxiety are at elevated risk for developing full-syndromal psychiatric disorders. However, no empirically based operationalization for these subthreshold disorders is available, leading to different outcomes in the literature regarding symptom features, correlates, and course. In this thesis, Karsten empirically operationalized subthreshold, yet clinically significant depression and anxiety leading to functional impairment, on the criterion that mental problems must be impairing to be regarded as clinically significant (the so called “clinical significance criterion of mental disorder”). More information is available from the RuG website.

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Femke Abma defends PhD thesis on work functioning

On 31 October Femke Abma, PhD student in PredSL PI Ute Bültmann’s group, will defend her thesis entitled ‘Work functioning development and evaluation of a measurement tool’.

In recent years, a change in the attention of occupational healthcare in the Netherlands from return-to-work towards stay-at-work has occurred. The shift towards stay at work requires new interventions and measures to assess effectiveness of interventions and to monitor work functioning. The thesis describes the development of a generic instrument that evaluates health-related work functioning to facilitate actions towards optimal functioning at work, sustainable work participation and work reintegration. The full press release is available from the RuG website.

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Older brains communicate differently

Ageing makes the networks in our brain less specific. Linda Geerligs, one of PredSL PI Natasha Maurits’ PhD students, used connectivity analysis of fMRI results to prove that the connections in our brain change as we grow older.

When compared with their younger counterparts, connectivity in the brain networks of older people decreases, while connectivity between brain networks increases. Linda also found evidence to suggest that the decrease in connectivity in the brain networks corresponds with slower reaction times and declining memory among the elderly. The research findings have been published online in Human Brain Mapping today.

The insights provided by this kind of fundamental research are very interesting. If we can discover exactly what changes in the brain during the ageing process and what the effects of these changes are, this will give us new leads for finding new treatments for elderly people with concentration and memory problems.

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