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Dive into the research topics where Johanna Assies is active.

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Featured researches published by Johanna Assies.


Biological Psychiatry | 2001

Significantly reduced docosahexaenoic and docosapentaenoic acid concentrations in erythrocyte membranes from schizophrenic patients compared with a carefully matched control group

Johanna Assies; Ritsaert Lieverse; Peter Vreken; R. J. A. Wanders; Peter M. Dingemans; Donald H. Linszen

BACKGROUND Fatty acid research in schizophrenia has demonstrated an altered cell membrane phospholipid metabolism. Erythrocyte membrane phospholipid composition closest reflects that of neuronal membranes. METHODS (Poly)(un)saturated fatty acid concentrations were measured in the erythrocyte membranes of 19, consecutively admitted, medicated young schizophrenic patients and then compared with matched control subjects. Psychiatric symptomatology was rated with the Positive and Negative Symptom Scale and Montgomery-Asberg Depression Rating Scale. Because diet, hormones, and cannabis influence fatty acid metabolism, we included these factors in our study. RESULTS The most distinctive findings concerned the omega-3 series: C22:5 omega-3, C22:6 omega-3 (docosahexaenoic acid), and the sum of omega-3 fatty acids were significantly decreased. Interestingly, C20:4 omega-6 (arachidonic acid) was not lowered. In the omega-9 series, higher levels of C22:1 omega-9 and lower levels its elongation product, C24:1 omega-9 (nervonic acid), were found. Interestingly, the other arm of the desaturation-elongation sequence of C18:1 omega-9, C20:3 omega-9, was lower in patients. The total omega-9 fatty acid levels were also lower in patients. CONCLUSIONS Significant differences in erythrocyte fatty acid composition were found. The differences were not due to diet or hormonal status and could not be explained by the medication or cannabis use. No consistent pattern emerged from the different fatty acid abnormalities and the clinical symptom scores.


Psychoneuroendocrinology | 2006

HPA- and HPT-axis alterations in chronic posttraumatic stress disorder

Miranda Olff; Yener Guzelcan; Giel-Jan de Vries; Johanna Assies; Berthold P. R. Gersons

Posttraumatic stress disorder (PTSD) has been associated with dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis as well as of the hypothalamus-pituitary-thyroid (HPT) axis. Findings have not been consistent and may depend on methodological issues like controlling for relevant variables. This study examines the levels of six HPA and HPT-axis related hormones in civilian PTSD patients without psychotropic medication. In a cross sectional study, 39 chronic PTSD patients and 44 healthy volunteers were included. Psychometric instruments included SCID, SI-PTSD, IES-R and BDI. The plasma hormones levels assessed were cortisol, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEA-S), prolactin, thyrotropin (TSH), and free thyroxin (fT4). Results showed that patients had significantly lower plasma cortisol, prolactin and TSH levels compared to the comparison group. The difference between TSH levels in patients and comparison subjects only emerged after controlling for relevant background variables. Furthermore, the severity of PTSD symptoms was negatively related to cortisol levels. Secondary analyses revealed no statistically significant effect of comorbid depression (26% of patients) on any of the hormone levels. Complex feedback mechanisms are likely to result in altered levels of stress related hormones in PTSD, and results depend on controlling for relevant variables. Further research with longitudinal designs is needed to find out whether these lower hormone levels are preexisting risk factors or consequence of trauma and whether these alterations are deleterious or adaptive.


Psychoneuroendocrinology | 2007

Changes in cortisol and DHEA plasma levels after psychotherapy for PTSD

Miranda Olff; Giel-Jan de Vries; Yener Guzelcan; Johanna Assies; Berthold P. R. Gersons

Post-traumatic stress disorder (PTSD) has been associated with dysregulation of the neuroendocrine system. In this study we examine the effects of psychotherapy in 21 PTSD patients, with and without coexisting depression, on the levels of six stress-related hormones: cortisol, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone-sulfate (DHEA-S), prolactin, thyrotropin (TSH) and free thyroxin (fT4). The results show that after brief eclectic psychotherapy (BEP) significant changes occurred in levels of cortisol and DHEA. Responders showed an increase in cortisol and DHEA levels, while in non-responders both hormone levels decreased. Differences were only found after controlling for depressive symptoms. In conclusion, effective psychotherapy for PTSD may alter dysregulations in the Hypothalamus-pituitary-adrenal (HPA)-axis, but comorbid depressive symptoms should be taken into account.


Journal of Neurology, Neurosurgery, and Psychiatry | 1999

Progression of abnormalities in adrenomyeloneuropathy and neurologically asymptomatic X-linked adrenoleukodystrophy despite treatment with "Lorenzo's oil"

B.M. van Geel; Johanna Assies; E.B. Haverkort; J.H.T.M. Koelman; Ben W.J.M. Verbeeten; Peter G. Barth

OBJECTIVES X-linked adrenoleukodystrophy (X-ALD) is an inherited disorder of peroxisomal fatty acid oxidation, biochemically characterised by the accumulation of saturated very long chain fatty acids (VLCFAs), particularly hexacosanoic acid (C26:0). Dietary treatment with a 4:1 mixture of glyceroltrioleate and glyceroltrierucate (“Lorenzo’s oil”) normalises plasma VLCFA concentrations, but neither ameliorates nor arrests the rapid progression of neurological symptoms in the cerebral variants of X-ALD. The efficacy of “Lorenzo’s oil” in the milder phenotypes of X-ALD was assessed, as this has been much less investigated. METHODS Twenty two patients who were treated with “Lorenzo’s oil” for at least 12 months for a median period of 2.5 (range 1.0–6.0) years were studied. Two had asymptomatic ALD, four the “Addison only” variant, 13 adrenomyeloneuropathy (AMN), and three were symptomatic female carriers. RESULTS The plasma C26:0 concentration normalised or near normalised in 19 patients (86%), in the three others it decreased significantly. Nevertheless, disability as measured with the extended disability status scale score increased mildly (0.5 (95% confidence interval (95% CI) 0.25–1.0)) in the 16 patients with neurological symptoms. Furthermore, one “Addison only” patient and one patient with AMN developed cerebral demyelination, and another “Addison only” patient developed AMN. Adrenocortical insufficiency evolved in one patient with AMN, and hypogonadism in one patient with asymptomatic ALD and two patients with AMN. Nerve conduction, evoked potential studies (SEP, BAEP, VEP), and abnormalities on cerebral MRI did not improve. On the other hand, side effects were often noted—namely, mild increases in liver enzymes (55%), thrombocytopenia (55%), gastrointestinal complaints (14%), and gingivitis (14%). We also found a mild decrease in haemoglobin concentration and leucocyte count. CONCLUSIONS The data suggest that treatment with “Lorenzo’s oil” neither improved neurological or endocrine function nor arrested progression of the disease. Furthermore, the oil often induced adverse effects. Therefore, it is advocated that “Lorenzo’s oil” should not be prescribed routinely to patients with X-ALD who already have neurological deficits.


PLOS ONE | 2010

Plasma and erythrocyte fatty acid patterns in patients with recurrent depression: a matched case-control study.

Johanna Assies; F. Pouwer; Anja Lok; Roel J. T. Mocking; Claudi Bockting; Ieke Visser; Nico G. G. M. Abeling; M. Duran; Aart H. Schene

Background The polyunsaturated fatty acid (PUFA) composition of (nerve) cell membranes may be involved in the pathophysiology of depression. Studies so far, focussed mainly on omega-3 and omega-6 PUFAs. In the present study, saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and PUFAs of the omega-3, -6 and -9 series in plasma and erythrocytes of patients with recurrent major depressive disorder (MDD-R) were compared with controls. Methodology and Principal Findings We carried out a case-control study. The sample consisted of 137 patients with MDD-R and 65 matched non-depressed controls. In plasma and erythrocytes of patients with MDD-R the concentrations of most of the SFAs and MUFAs, and additionally erythrocyte PUFAs, all with a chain length >20 carbon (C) atoms, were significantly lower than in the controls. In contrast, the concentrations of most of the shorter chain members (≤18C) of the SFAs and MUFAs were significantly higher in the patients. Estimated activities of several elongases in plasma of patients were significantly altered, whereas delta-9 desaturase activity for C14∶0 and C18∶0 was significantly higher. Conclusions/Significance The fatty acid status of patients with MDD-R not only differs with regard to omega-3 and omega-6 PUFAs, but also concerns other fatty acids. These alterations may be due to: differences in diet, changes in synthesizing enzyme activities, higher levels of chronic (oxidative) stress but may also result from adaptive strategies by providing protection against enhanced oxidative stress and production of free radicals.


Neurology | 1994

Predominance of the adrenomyeloneuropathy phenotype of X‐linked adrenoleukody strophy in the Netherlands: A survey of 30 kindreds

B. M. van Geel; Johanna Assies; G. J. Weverling; Peter G. Barth

X-linked adrenoleukodystrophy (X-ALD) is an inherited disorder of peroxisomal β-oxidation associated with accumulation of saturated very long-chain fatty acids, which results in central and peripheral demyelination and in impaired function of adrenal cortex and testes. The phenotypic expression is highly variable, childhood cerebral ALD (CCALD) and adrenomyeloneuropathy (AMN) being the main variants. We explored the 30 Dutch kindreds well known to the Dutch X-ALD/AMN Study Group and phenotyped 77 male patients: 35 (46%) had AMN and 24 (31%) CCALD or adolescent cerebral ALD (AdolCALD). These percentages differ significantly from previous reports, in which 25 to 28% of the patients developed AMN and 53 to 57% CCALD or AdolCALD. Our findings indicate that—at least in the Netherlands—AMN may be the most frequent phenotype of X-ALD.


Translational Psychiatry | 2016

Meta-analysis and meta-regression of omega-3 polyunsaturated fatty acid supplementation for major depressive disorder.

Roel J. T. Mocking; I Harmsen; Johanna Assies; Maarten W. J. Koeter; Henricus G. Ruhé; Aart H. Schene

Omega-3 polyunsaturated fatty acid (PUFA) supplementation has been proposed as (adjuvant) treatment for major depressive disorder (MDD). In the present meta-analysis, we pooled randomized placebo-controlled trials assessing the effects of omega-3 PUFA supplementation on depressive symptoms in MDD. Moreover, we performed meta-regression to test whether supplementation effects depended on eicosapentaenoic acid (EPA) or docosahexaenoic acid dose, their ratio, study duration, participants’ age, percentage antidepressant users, baseline MDD symptom severity, publication year and study quality. To limit heterogeneity, we only included studies in adult patients with MDD assessed using standardized clinical interviews, and excluded studies that specifically studied perinatal/perimenopausal or comorbid MDD. Our PubMED/EMBASE search resulted in 1955 articles, from which we included 13 studies providing 1233 participants. After taking potential publication bias into account, meta-analysis showed an overall beneficial effect of omega-3 PUFAs on depressive symptoms in MDD (standardized mean difference=0.398 (0.114–0.682), P=0.006, random-effects model). As an explanation for significant heterogeneity (I2=73.36, P<0.001), meta-regression showed that higher EPA dose (β=0.00037 (0.00009–0.00065), P=0.009), higher percentage antidepressant users (β=0.0058 (0.00017–0.01144), P=0.044) and earlier publication year (β=−0.0735 (−0.143 to 0.004), P=0.04) were significantly associated with better outcome for PUFA supplementation. Additional sensitivity analyses were performed. In conclusion, present meta-analysis suggested a beneficial overall effect of omega-3 PUFA supplementation in MDD patients, especially for higher doses of EPA and in participants taking antidepressants. Future precision medicine trials should establish whether possible interactions between EPA and antidepressants could provide targets to improve antidepressant response and its prediction. Furthermore, potential long-term biochemical side effects of high-dosed add-on EPA supplementation should be carefully monitored.


Acta Psychiatrica Scandinavica | 2014

Effects of oxidative stress on fatty acid- and one-carbon-metabolism in psychiatric and cardiovascular disease comorbidity

Johanna Assies; Roel J. T. Mocking; Anja Lok; Henricus G. Ruhé; F. Pouwer; Aart H. Schene

Cardiovascular disease (CVD) is the leading cause of death in severe psychiatric disorders (depression, schizophrenia). Here, we provide evidence of how the effects of oxidative stress on fatty acid (FA) and one‐carbon (1‐C) cycle metabolism, which may initially represent adaptive responses, might underlie comorbidity between CVD and psychiatric disorders.


Psychiatry Research-neuroimaging | 2004

Elevated salivary dehydroepiandrosterone-sulfate but normal cortisol levels in medicated depressed patients: preliminary findings

Johanna Assies; Ieke Visser; Nancy A. Nicolson; Teunis A. Eggelte; Elisabeth M. Wekking; Jochanan Huyser; Ritsaert Lieverse; Aart H. Schene

Major depression is often associated with dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. In contrast to cortisol, dehydroepiandrosterone-sulfate (DHEA-S) has been less extensively studied in depressed patients. This study examined salivary morning and evening levels of cortisol and DHEA-S in 13 medicated, unipolar, non-psychotic depressed patients and 13 healthy volunteers. Diurnal declines in cortisol and DHEA-S levels were found in both depressed and control groups. In patients compared with controls, DHEA-S was significantly elevated, in conjunction with normal cortisol levels. Based on DHEA-S at 22:00 h only, 77% of the subjects were correctly classified in a discriminant analysis as depressed or control. When simultaneously entered in a multiple regression analysis, DHEA-S (morning and evening) and cortisol (evening only) predicted symptom severity in depressed patients. These preliminary results suggest that DHEA-S may be a more sensitive indicator of depression and symptom severity than cortisol in medicated but still clinically depressed patients.


Psychiatry Research-neuroimaging | 2012

Lower cortisol levels predict recurrence in remitted patients with recurrent depression: A 5.5 year prospective study

Claudi Bockting; Anja Lok; Ieke Visser; Johanna Assies; Maarten W. J. Koeter; Aart H. Schene

Major Depressive Disorder (MDD) is a highly recurrent disease. Stress-responsive system dysfunction seems to persist after remission. In patients with more chronic and recurrent depressive episodes, state related HPA-axis dysregulation might be a risk factor for prospective recurrence. This study examines the predictive effect of cortisol on consecutive episodes in remitted recurrently depressed patients. Cortisol was assessed in saliva in remitted recurrently depressed patients (n=55) that were followed up prospectively for 5.5 years after remission. Recurrence was assessed using a well validated structured interview. Lower mean morning cortisol levels predicted earlier time to recurrence over 5.5 year after correction for residual symptoms (p=0.015). Residual symptoms and childhood trauma slightly confounded the association between cortisol and recurrence. Lower cortisol levels were associated with having experienced traumatic childhood life events (42.3% in patients with lower cortisol versus 19.2% in patients with higher cortisol). Our study provides further support for the predictive role over 5.5 year of HPA axis dysregulation, i.e. lower morning cortisol levels, of recurrence in recurrently depressed patients. Childhood trauma is associated to having lower cortisol levels. It might have long term consequences for dealing with stress and the HPA-axis.

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Aart H. Schene

Radboud University Nijmegen

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Anja Lok

University of Amsterdam

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Ieke Visser

University of Amsterdam

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Miranda Olff

University of Amsterdam

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