Biomedical subjects

B Minner

Publications and source records attributed to B Minner.

18 recordsLinked to original sources

PubMed1995

Increased plasma serine concentrations in depression.

Recently, it has been shown that higher plasma serine concentrations are a possible biological marker for psychoses including schizophrenia. The present study was carried out in order to investigate plasma serine levels in 123 depressed subjects (41 minor; 47 simple major; 35 melancholic depressives) and 50 normal controls. It was found that plasma serine concentrations were significantly higher in depressed subjects than in normal controls. There were no significant correlations between plasma serine and postdexamethasone cortisol values. Dexamethasone administration had a significant suppressive effect on plasma serine levels in depression but not in normal controls. In the latter--but not in depressed subjects--there were significant positive correlations between plasma serine and L-tryptophan concentrations.

Adult↗

PubMed1993

Sleep disorders and anxiety as symptom profiles of sympathoadrenal system hyperactivity in major depression.

Recently, it has been reported that major depression is accompanied by an increased sympathoadrenal system (SAS) activity. In order to study the psychopathological correlates of SAS activity in depression, the authors measured the 24 h urinary excretion of catecholamines (CA), i.e., noradrenaline (NE), adrenaline (E), dopamine (DA) and the NE/E metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) in 80 unipolar depressed subjects. The excretion of these indices of SAS activity have been studied in relation to the depressive items of the Structured Clinical Interview for DSM-III (SCID) and the Hamilton Depression Rating Scale (HDRS). There were significant positive correlations between the SCID item sleep disorders and the HDRS item middle insomnia, on the one hand, and NE, E and DA excretion, on the other. The MHPG excretion in 24 h urine was significantly and negatively related to somatic anxiety and hypochondriasis. It is suggested that these intertwined relationships between increased CA turnover, sleep discontinuity and anxiety may reflect the occurrence of a hyperarousal state in some major depressives that may be regarded as a coping response to various putative noxious stimuli.

Adrenal Glands↗

PubMed1993

Autoimmunity in depression: increased antiphospholipid autoantibodies.

Some groups have recently reported higher titers of autoantibodies in depressed subjects than in normal controls. The present study investigates whether depressed patients exhibit increased antiphospholipid antibody titers compared with normal controls. The authors measured the binding index (BI) of antiphosphatidylserine (APSA), antipartial thromboplastin (APTA) and anticardiolipin (ACA) in 22 minor, 23 simple major and 20 melancholic depressives, 10 healthy controls and 104 normal controls with negative autoantibody sera. Depressed subjects exhibited significantly higher APSA and APTA antibody titers compared with normal controls. A large number of depressed subjects (+/- 54%) showed APTA and APSA positivity, defined as BI > or = 2 standard deviations above the mean BI of normal controls. There was a significant discrimination (> or = 2.8 standard deviations) between melancholic subjects and healthy controls with respect to BI of ACA, APSA and APTA. However, by using a more conservative value for phospholipid positivity (i.e., BI > or = 5 standard deviations above the mean BI of a reference sample of normal sera), the subject's autoantibody titers were, on the whole, within the normal range. Our results point towards a higher expression of antiphospholipid antibodies during depression but a much lower incidence of positive patients than in classical autoimmune disorders, such as systemic lupus erythematosus.

Adult↗

PubMed1992

Evidence for a systemic immune activation during depression: results of leukocyte enumeration by flow cytometry in conjunction with monoclonal antibody staining.

Several studies have reported a suppressed immune function (e.g. blast transformation) during depression. In an attempt to define the cellular basis of the reported immune disorders, the present study investigates the leukocyte cell subset profile of minor, simple major, and melancholic depressives, versus normal controls. We have counted the number of white blood cells (WBC) lymphocytes, monocytes, and granulocytes, while the number of lymphocyte (sub)populations has been identified by phenotype, using monoclonal antibody staining in conjunction with flow cytometry. The following cell surface antigens were determined: CD3+ (pan T), CD19+ (pan B), CD4+ (T helper/inducer), CD8+ (T suppressor/cytotoxic), CD4+CD45RA (T-memory cells), CD4+CD45RA+ (T-virgin cells), surface Ig, class II MHC HLA-DR, and CD25+ (IL-2 receptor). By means of pattern recognition methods, we established distinct immunological changes in minor and simple major depressed and in melancholic patients, setting them apart from the reference population. Depression, per se, is characterized by a higher number of WBC, monocytes, class II MHC HLA-DR, and memory T cells. Minor and simple major depressives exhibited an increased T helper/suppressor ratio. Increased numbers of IL-2 receptor bearing cells are a hallmark for major depression. Melancholics showed an increased number of pan T, pan B and T suppressor/cytotoxic cells. It was concluded that the established immune cell profile of depressed patients may point towards the existence of a systemic immune activation during that illness.

Adjustment Disorders↗

PubMed1991

Decreased serum dipeptidyl peptidase IV activity in major depression.

It has been recently shown that severe depression is characterized by immune dysfunctions such as blunted mitogen-induced blast transformation, which is linked to interleukin-2 (IL-2) mechanisms, and to autoimmune responses. In order to explore one of the putative pathophysiological mechanisms underlying both factors, we have measured the predexamethasone and postdexamethasone serum dipeptidyl-peptidase IV (DPP IV) activity in depressed inpatients and normal controls. This enzyme is an important mediator of IL-2-related blast proliferation, and it may play a role in autoimmunity. We found significantly lower DPP IV levels in major depressives as compared with healthy controls, and melancholics exhibited significantly lower enzyme activity than minor depressives. There was a significant negative correlation between serum DPP IV activity and the severity of illness. However, we were unable to detect any significant relationships between DPP IV on the one hand, and mitogen-induced blast transformation, soluble IL-2 receptor accumulation in PHA culture supernatant, total number of leukocytes and lymphocytes, T lymphocytes, CD4+ and CD25+ cells, on the other. Men exhibited significantly higher serum DPP IV levels than women.

Adjustment Disorders↗

PubMed1991

Coexisting dysregulations of both the sympathoadrenal system and hypothalamic-pituitary-adrenal-axis in melancholia.

In order to delineate putatively coexisting dysregulations between sympathoadrenal system and hypothalamic-pituitary-adrenal (HPA)-axis during depression, the authors measured the following: the pre and postdexamethasone (1 mg) 24 hr urine excretion of noradrenaline, dopamine, adrenaline, 3-methoxy-4-hydroxyphenylglycol (MHPG), free cortisol (UFC), and plasma cortisol. Melancholic patients were characterized by a significantly higher excretion of noradrenaline, dopamine and adrenaline, combined with significantly increased UFC, postdexamethasone plasma cortisol, and UFC values. We found significant and positive correlations between UFC on the one hand, and the 24hr urine excretion of noradrenaline, dopamine, and adrenaline, on the other. By the same token, we established significant relationships between the 24 hr urine excretion of those catecholamines and the postdexamethasone UFC and plasma cortisol values. Cortisol nonsuppressors exhibited a significantly higher excretion of noradrenaline, dopamine and adrenaline, as compared with cortisol suppressors. Dexamethasone administration did not have a significant effect on the urinary output of noradrenaline, dopamine, adrenaline or MHPG.

Adrenal Glands↗

PubMed1991

Serum postdexamethasone prolactin measures in depressive patients and control subjects.

Recently, some researchers noted significant positive relationships between postdexamethasone serum cortisol and prolactin levels, whilst endogenous depressives exhibited a significantly lower suppression of prolactin by dexamethasone than non-endogenous patients or normal controls. To ascertain the extent of prolactin responses to dexamethasone in severely depressed patients, we measured 8 a.m. pre- and postdexamethasone prolactin levels in 104 depressed and 42 normal subjects. Serum cortisol levels were also determined in depressed patients before and after dexamethasone administration. We found a significant suppressive effect of dexamethasone on prolactin levels. There were no significant differences either in pre- or postdexamethasone prolactin, or in actual dexamethasone-induced decrements in prolactin between normal controls, melancholics, simple major or minor depressed subjects. We have not found any significant relationships between cortisol and prolactin, either under baseline or postdexamethasone conditions.

Adjustment Disorders↗

PubMed1991

HPA-axis hormones and prolactin responses to dextro-fenfluramine in depressed patients and healthy controls.

1. Like other authors we have established disturbances in central serotonergic neurotransmission in severely depressed patients by implementing hypothalamic pituitary adrenal (HPA)-axis hormones and prolactin responses to serotonin agonists or precursors. 2. Challenge probes with D,L fenfluramine have yielded controversial results. This substance, however, is not as serotonin-selective as previously believed. 3. Dextro(D)-fenfluramine, the dextrorotatory isomer of fenfluramine, constitutes a specific and potent serotonergic agonist. 4. In the present study the authors determined the following in healthy volunteers, and in depressed inpatients: the adrenocorticotropic hormone (ACTH), beta endorphin, prolactin and cortisol responses to D-fenfluramine administration (45 mg orally), total L-tryptophan and the 8 a.m. postdexamethasone cortisol values. 5. We found no significant differences in any of the post-D-fenfluramine hormone levels across healthy controls, minor, simple major and melancholic depressives. There were no significant correlations between L-tryptophan or postdexamethasone cortisol on the one hand, and any of the post-D-fenfluramine hormone values on the other.

Adrenocorticotropic Hormone↗

PubMed1991

Cortisol escape from suppression by dexamethasone during depression is strongly predicted by basal cortisol hypersecretion and increasing age combined.

We determined baseline 0800h plasma cortisol concentrations, 24-hr urinary free cortisol (UFC) excretion, the post-dexamethasone cortisol values at 0800h and 1600h, and the 0800h dexamethasone concentrations in 60 depressed patients categorized according to the DSM-III. Up to 59% of the variability in the 0800h post-dexamethasone cortisol values could be explained by the multiple regression on UFC, 0800h basal plasma cortisol, age (all positively related), and dexamethasone concentrations (negatively related). The 1600h post-dexamethasone cortisol data were best explained (i.e., 55% of the variance) by the multiple regression on basal plasma cortisol, UFC (positive) and dexamethasone (negative). After controlling for UFC, baseline plasma cortisol, and age no significant effects of the depressive state (diagnostic classification or severity of illness) on the post-dexamethasone cortisol values could be detected. It can be deduced that cortisol non-suppression during depression is related strongly to baseline cortisol hypersecretion and increasing age. These factors are additive and contribute independently towards cortisol escape from suppression by dexamethasone.

Adult↗

PubMed1991

A further exploration of the relationships between immune parameters and the HPA-axis activity in depressed patients.

In order to investigate the relationship between the immune apparatus and the hypothalamic-pituitary-adrenal (HPA)-axis activity in depressed patients, we measured in vitro lymphocyte responses to the mitogens Phytohaemagglutinin (PHA), Pokeweed (PWM) and Concanavalin A (Con A) and 8 a.m. baseline cortisol values in plasma, free cortisol excretion in 24 h urine (UFC), basal and post-dexamethasone beta-endorphin values. Major depressed patients with melancholia/psychotic features exhibited a significantly lower mitogen-induced blast transformation as compared to minor and simple major depressed patients. The lymphocyte responses to the three mitogens were significantly inversely related to baseline cortisol values and postdexamethasone beta-endorphin values. The proliferative capacity of lymphocytes to stimulation with PHA and PWM was significantly and positively related to UFC excretion. Up to 45% of the variance in the immune-responses to the mitogens was explained by the baseline cortisol, post-dexamethasone beta-endorphin and UFC values.

Adult↗

PubMed1991

A multivariate study of simultaneous escape from suppression by dexamethasone of urinary free cortisol, plasma cortisol, adrenocorticotropic hormone and beta-endorphin in melancholic patients.

To investigate the relationships between pre- and postdexamethasone hypothalamic-pituitary-adrenal (HPA) axis functioning in depression, we measured the levels of baseline and postdexamethasone urinary free cortisol (UFC), plasma cortisol, adrenocorticotropic hormone (ACTH) and beta-endorphin. We found that dexamethasone significantly suppressed all hormone levels. All 4 postdexamethasone hormones--but not their baseline levels--were significantly higher in melancholic subjects than in minor and simple major depressives. We have accumulated evidence that the melancholic and minor depression groups form discrete classes in postdexamethasone HPA axis hormone levels; this supports the biological heterogeneity hypothesis of melancholia. We found that a combination of the postdexamethasone UFC and beta-endorphin values yielded the most significant diagnostic tool for melancholia. Our results suggest that the measurements of both hormones may constitute the most accurate index reflecting the HPA axis escape from suppression by dexamethasone in melancholia. By means of pathway analysis, we determined the causal relationships between age, dexamethasone circulating levels, diagnostic depression classification and the various baseline and postdexamethasone hormone values.

Adrenocorticotropic Hormone↗

PubMed1990

Prediction of the DST results in depressives by means of urinary-free cortisol excretion, dexamethasone levels, and age.

This study investigates the relationships between cortisol escape from suppression by dexamethasone during a depressive episode, and the baseline activity of the hypothalamic-pituitary-adrenal (HPA) axis, circulating dexamethasone levels, and age. To this end, we measured urinary-free cortisol (UFC) excretion in 24-hr urine samples and the 8 AM cortisol and dexamethasone levels after administration of 1 mg dexamethasone in 50 depressive patients. We found that up to 54% of the variance in the postdexamethasone cortisol values could be explained by the multiple regression on UFC, age, and dexamethasone levels. By utilizing these three parameters, the dexamethasone suppression test (DST) nonsuppressor/suppressor state was correctly identified in 92% of the subjects. It was shown that an important part of the variance in postdexamethasone cortisol is actually background variance, irrelevant to depression and produced by the cumulative effects of the three aforementioned parameters. Only a small part (less than 20%) of the variance in postdexamethasone cortisol is determined by the actual depressive state. It was concluded that (1) baseline hypersecretion of cortisol, (2) decrements in the bioavailability of the test substance, (3) increasing age, and (4) the depressive state per se--all of which are cumulative--contribute independently to cortisol escape from suppression by 1 mg dexamethasone.

Adult↗

PubMed1990

Effects of dexamethasone on the availability of L-tryptophan and on the insulin and FFA concentrations in unipolar depressed patients.

Several authors have shown that the availability of L-tryptophan (L-TRP) in the serum is lower in patients with major depression than in controls. It has recently been reported that the administration of a dose of dexamethasone sufficient to cause cortisol suppression also caused significant decrements in the availability of L-TRP. In order to elucidate the putative pathophysiological mechanisms underlying this decreased L-TRP disposition, the authors examined 37 depressed women categorized according to the DSM-III. L-TRP, the sum of five competing amino acids (CAA), the L-TRP/CAA ratio, and insulin and free fatty acid (FFA) levels were determined both before and after oral administration of 1 mg dexamethasone. The availability of L-TRP was significantly lower in depressed women with melancholia compared with simple major and minor depressives. The baseline disposal of L-TRP was related neither to insulin nor to FFA concentrations Dexamethasone administration significantly reduced the L-TRP and L-TRP/CAA values and increased FFA and insulin levels. Postdexamethasone L-TRP and FFA levels were significantly and positively correlated.

Adjustment Disorders↗

PubMed1990

Suppressant effects of dexamethasone on the availability of plasma L-tryptophan and tyrosine in healthy controls and in depressed patients.

Formation in the brain of serotonin from L-tryptophan (L-TRP) and noradrenaline from tyrosine are pathways related to the pathophysiology of major depression and to the regulation of the hypothalamic-pituitary-adrenal (HPA) axis. In the past, decrements in L-TRP availability and disorders in the HPA axis have repeatedly been observed in major depressed patients; both factors were shown to be inversely correlated. In order to investigate the relationships between glucocorticosteroid activity and the availability of L-TRP and tyrosine, the authors measured L-TRP, tyrosine, valine, leucine, isoleucine and phenylalanine in baseline conditions and after treatment with 1 mg dexamethasone in 16 healthy controls and in 50 depressed patients. The ratios between L-TRP and tyrosine and the sums of the amino acids known to compete with them during transport across the blood-brain barrier were computed as an index of (respectively) the serotonin and noradrenaline synthesis in the brain. We found significantly decreased plasma L-TRP and tyrosine levels after treatment with dexamethasone compared with basal levels. Accordingly, the plasma ratios between L-TRP and tyrosine and the sum of the competing amino acids were significantly reduced by dexamethasone administration. It was hypothesized that through these actions of dexamethasone on peripheral amino acids, the central noradrenaline and serotonin control over the HPA-axis could be altered.

Adult↗

PubMed1989

Cortisol, ACTH, prolactin and beta-endorphin responses to fenfluramine administration in major-depressed patients.

In the past, some researchers found increased cortisol and prolactin responses to the administration of fenfluramine in major-depressed patients. It was believed that the fenfluramine test could prove to constitute another challenge probe to reflect the central serotonergic function. The present study was conducted in order to investigate the pituitary/adrenal responses to fenfluramine in major- versus minor-depressed patients. To this end we administered 60 mg D,L-fenfluramine p.o. to 40 depressed patients categorized according to the DSM-III. The basal levels of cortisol, adrenocorticotrophic hormone (ACTH), beta-endorphins and prolactin and their levels 2 and 4 h after fenfluramine administration were measured. We found no significant effect for fenfluramine treatment on cortisol, ACTH or beta-endorphins. There was a significant (p = 0.02) effect for fenfluramine treatment on prolactin. The enhanced secretion of prolactin was only significant (p = 0.006) in major (296.X2, 296.X3, 296.X4) and not in minor (300.40, 309.00) depressives. It was concluded that our findings corroborate the thesis of a hypersensitive serotonergic neurotransmission during a major depressive episode.

Adrenocorticotropic Hormone↗

PubMed1989

Impaired lymphocyte stimulation by mitogens in severely depressed patients. A complex interface with HPA-axis hyperfunction, noradrenergic activity and the ageing process.

To investigate the relationships between the immune apparatus, major depression, and HPA-axis and noradrenergic activity, the authors measured the lymphocyte stimulation responses to the mitogens phytohaemagglutinin (PHA), pokeweed mitogen (PWM) and concanavalin A (CON A), post-dexamethasone cortisol (DST) values and 3-methoxy-4-hydroxyphenylglycol (MHPG) excretion in 24-hour urine samples from 48 patients. We found that lymphocyte responses to PHA and PWM in melancholic and psychotic depressives were significantly lower than in minor depressives. The lymphocyte responses to PHA, PWM and CON A showed significantly negative correlations with age, DST results and HRSD score. Responses to PHA were significantly negatively correlated with MHPG excretion. Up to +/- 33% of the variance in the three mitogenic lymphocyte responses could be explained by canonical correlation with age, DST results and MHPG values.

Adult↗

PubMedDate not supplied

The influences of dexamethasone levels on the predictive value of the DST for unipolar major depression and the relationships between post-dexamethasone cortisol and ACTH levels.

To investigate the relationships between dexamethasone (DEX) and post-DEX cortisol and adrenocorticotropic hormone (ACTH) levels, the authors measured DEX at 8.00 a.m. and post-DEX cortisol and ACTH levels at 8.00 a.m. and 4.00 p.m. in 72 depressed patients categorized according to DSM-III. Cortisol non-suppressors exhibited significantly (P = 0.0006) decreased levels of DEX compared to suppressors. DEX levels at 8.00 a.m. explained 21.1% of the variance in the post-DEX cortisol values at 8.00 a.m. and 34.5% of those at 4.00 p.m. DEX levels were not significantly different among minor depressives (300.40, 309.00), major depressives without melancholia (296.X2) or with melancholia and/or psychotic features (296.X3, 296.X4). In the latter the post-DEX cortisol was significantly increased compared to all other depressives and these differences remained significant even after adjusting for the variations in DEX (by means of regression analysis). Also the diagnostic performance of the post-DEX cortisol values for major depression with associated features versus minor depression was not substantially affected when the DEX levels were accounted for. ACTH levels after DEX were shown to correlate significantly (P less than 0.05) and negatively with DEX. Although post-DEX ACTH levels did not differ among the DSM-III diagnostic categories, cortisol non-suppressors averaged significantly (P = 0.0004) higher ACTH levels than suppressors.

Adrenocorticotropic Hormone↗

PubMedDate not supplied

Immune cell parameters in severely depressed patients: negative findings.

Cross-sectional population studies reported decreased mitogen-induced lymphocyte responsiveness in severely depressed patients. This immunologic impairment, indicative of T- and/or B-cell dysfunction, was related to disturbances in the dexamethasone suppression test (DST) and to age effects. Glucocorticoid overdrive, a hallmark for severe depression, exerts immunosuppressive effects through the impact on neutrophils, lymphocytes, and monocytes and natural killer cells (NKC). This paper has analyzed the relation of peripheral blood immune parameters to severe depression, DST results and age. The population consisted of 37 inpatients categorized according to DSM-III as minor depression (300.40, 309.00), simple major depression (296.X2) or major depression with melancholia and/or with psychotic features (296.X3, 296.X4). The number of leukocytes, neutrophils, lymphocytes and monocytes was counted. T-cell (total T-cell, T-helper, T-suppressor, HLA-DR), B-cell (LN1 and immunoglobulin (Ig) receptors), monocytes (M1 and M3 membrane antigens) and NKC activity were identified by phenotype using monoclonal antibodies. No differences were detected between the depressive subgroups for any of the parameters examined. There were no relationships between these immune variables and the severity of illness, DST results or age.

Adult↗