Francesca Brambilla

Neuroendocrine responses to experimentally-induced psychological stress in healthy humans

Previous studies of hormonal and neurophysiological changes in response to psychological stress in humans have produced contrasting findings due to differing experimental procedures and consistent individual variability. Habituation effects, which influence physiological coping in response to exposure to repeated stress, need to be investigated more extensively. In the present study, twenty healthy male subjects were each exposed twice to the same psychosocial stressor (Stroop Color Word Interference task, public speaking and mental arithmetic in front of an audience) during a first session (day 1) and a second session (day 8). Plasma concentrations of norepinephrine (NE), epinephrine (EPI), adrenocorticotropic hormone (ACTH), cortisol (CORT) and prolactin (PRL) were measured immediately before the beginning of the tests and at their end, 30 min later, on both experimental days. For the total group, NE, EPI, ACTH, and CORT levels were significantly elevated, and PRL levels were significantly decreased, after stress exposure on day 1. ACTH and CORT levels showed less significant increases after stress on day 8. In contrast, NE and EPI responses to stress were not significantly blunted, and PRL response was unchanged on day 8. Cluster analysis revealed two groups of subjects who showed different habituation patterns for ACTH and CORT. The first group (n=12) of subjects showed a reduction of ACTH and CORT responses to stress on day 8. The subjects of the second group (n=8) displayed a significant increase of ACTH and cortisol in response to stress on day 8, without any habituation effect. These results increase the evidence concerning the involvement of the HPA axis and catecholamines in response to psychological stress, and suggest that possible individual differences in the neuroendocrine coping mechanisms may affect mood regulation and the state of health.

Neuroendocrine Responses to Psychological Stress in Adolescents with Anxiety Disorder

Neurotransmitter-neuroendocrine and cardiovascular responses to the administration of a psychologically stressful mixed-model test (Mental Arithmetic, Stroop Color Word Interference Task, Trier Social Stress Test) were examined in 20 male peripubertal subjects affected by anxiety disorder (group A: 14 with generalized anxiety disorder, 6 with generalized anxiety disorder and separation anxiety disorder) and 20 junior school adolescents, matched for age, without overt psychological disorders (group B). Plasma levels of norepinephrine (NE), epinephrine (EPI), adrenocorticotropic hormone (ACTH), β-endorphin (β-EP), cortisol (CORT), growth hormone (GH), prolactin (PRL) and testosterone (Te) were measured immediately before the beginning of the tests and 30 min later at their end. Mean prestress values of GH, PRL, β-EP and ACTH were significantly higher in anxious subjects than in controls. There was no difference in NE, EPI, CORT and Te prestress levels in the two groups. After the psychological stress session NE, GH and Te concentrations increased significantly in anxious subjects (A), but not in controls. In contrast, β-EP and PRL decreased significantly during the psychological stress session in anxious subjects, and were unaffected by stress in the subjects without anxiety. No significant changes were found in ACTH, CORT and EPI during the challenge either in anxious subjects or in controls, which may be attributed to the late time of poststress blood sampling. In contrast to controls, heart rate and systolic blood pressure increased significantly in anxious subjects after psychological stress testing. Our data support the hypothesis that the hyperactivity of the noradrenergic system in response to stress is associated with anxiety disorders in adolescents and might influence the responses of GH and Te. High prestress basal values of stress hormones seem to be induced in anxious subjects by the anticipation of the task or by a persistent hyperactivity of the noradrenergic system. Further studies are needed to investigate in more detail the involvement of the HPA axis in anxious adolescents by a more refined resolution of time points of blood sampling.

Reliable typing of systemic amyloidoses through proteomic analysis of subcutaneous adipose tissue

Considering the important advances in treating specific types of systemic amyloidoses, unequivocal typing of amyloid deposits is now essential. Subcutaneous abdominal fat aspiration is the easiest, most common diagnostic procedure. We developed a novel, automated approach, based on Multidimensional Protein Identification Technology, for typing amyloidosis. Fat aspirates were obtained from patients with the most common systemic amyloidoses (ALλ, ALκ, transthyretin, and reactive amyloidosis), with Congo red score more than or equal to 3+, and nonaffected controls. Peptides from extracted and digested proteins were analyzed by Multidimensional Protein Identification Technology. On semiquantitative differential analysis (patients vs controls) of mass spectrometry data, specific proteins up-represented in patients were identified and used as deposit biomarkers. An algorithm was developed to classify patients according to type and abundance of amyloidogenic proteins in samples; in all cases, proteomic characterization was concordant with fibril identification by immunoelectron microscopy and consistent with clinical presentation. Our approach allows reliable amyloid classification using readily available fat aspirates.

Olanzapine therapy in anorexia nervosa: psychobiological effects.

Dopamine impairments occur in anorexia nervosa. The aim of this study was to see whether treatment with the atypical dopamine antagonist antipsychotic olanzapine improves the disorder. Thirty anorexics, 18 restricted and 12 bingeing–purging, underwent a 3-month course of cognitive behavioral therapy, plus at random and double-blinded oral olanzapine (2.5 mg for 1 month, 5 mg for 2 months) in half and oral placebo in the other half of them. BMI, psychopathological aspects (eating disorder inventory, Hamilton Rating Scale, Buss–Durkee Rating Scale, Yale Brown Cornell for Eating Disorders Rating Scale, temperament–character inventory), and homovanillic acid blood concentrations for dopamine secretion, were monitored at baseline and then monthly during the trial. At the end of the trial BMI, total eating disorder inventory, total Yale Brown Cornell for Eating Disorders Rating Scale, Buss–Durkee Rating Scale, Hamilton Rating Scale scores and in olanzapine-treated patients the subitems of eating disorder inventory ineffectiveness and maturity fear, of Buss–Durkee Rating Scale direct aggressiveness, of temperament–characteristic inventory persistence had improved significantly. When stratified for anorexia nervosa subtype, BMI changes were significant among anorexia nervosa bingeing-purging patient, ‘depression’ (Hamilton Rating Scale) and ‘direct aggressiveness’ (Buss–Durkee Rating Scale) among anorexia nervosa bingeing–purging patients, ‘persistence’ (temprerament–characteristic inventory), among anorexics restricted patients, with a trend toward significance for obsessivity–compulsivity (Yale Brown Cornell for Eating Disorders Rating Scale). homovanilic acid blood levels increased significantly in the cognitive behavioral therapy+olanzapine group. No correlations were observed between homovanilic acid concentrations and psychopathological parameters. The pharmacological treatment can significantly improve specific aspects of anorexia nervosa.

Long-term immune-endocrine effects of bereavement: relationships with anxiety levels and mood

Psychological, endocrine and immune parameters were measured over a 6-month period in 14 healthy subjects who underwent an unpredictable acute emotional stress (e.g. sudden death of a loved one) compared with 14 controls who did not. Probands were profoundly stressed as assessed 10 days after bereavement by their scores on the Hamilton Rating Scales of Anxiety and Depression, adrenocorticotropin and cortisol plasma concentrations, and non-suppression in response to dexamethasone. Functional alterations of immune parameters, such as responsiveness of peripheral blood lymphocytes to mitogens, were found 40 days after bereavement. Despite a normal number of circulating lymphocyte subsets, the functional activity of natural killer (NK) cells was markedly reduced at day 40. Changes in the intracellular concentration of beta-endorphin in peripheral blood mononuclear cells correlated with anxiety and depression scores. Controls showed no changes in psychometric, endocrine and immune measures during the 6-month study. Cluster analysis revealed two groups of bereaved subjects with different patterns of immune and endocrine changes: (1) Five subjects, characterized by harm-avoidant temperament and long-lasting dysphoric mood, showed reduced responsiveness of peripheral blood lymphocytes to mitogens, decreased NK cell activity and non-suppression in response to dexamethasone that persisted for 6 months. (2) Nine subjects showed significant changes only during the early phase after bereavement. Our data suggest that the immunological consequences of stress do not simply overlap with psychological and endocrine alterations, and are particularly severe and long-lasting in a subgroup of subjects, indicating the importance of individual variability in the capacity to cope with stress.

Psychoimmunoendocrine Aspects of Panic Disorder

Immunological, neuroendocrine and psychological parameters were examined in 14 psychophysically healthy subjects and in 17 panic disorder patients before and after a 30-day course of alprazolam therapy. T lymphocyte proliferation in response to the mitogen phytohemagglutinin, lymphocyte beta-endorphin (beta-EP) concentrations, plasma ACTH, cortisol and beta-EP levels were examined in basal conditions and after corticotropin-releasing hormone (CRH) stimulation. Cortisol inhibition by dexamethasone (DST) and basal growth hormone (GH) and prolactin levels were also examined. Depression, state or trait anxiety, anticipatory anxiety, agoraphobia, simple and social phobias, severity and frequency of panic attacks were monitored by rating scales. The immune study did not reveal any significant difference between patients and controls, or any effect of alprazolam therapy. The hormonal data for the two groups were similar, except for higher than normal basal ACTH and GH plasma levels, lower than normal ratios between the ACTH and cortisol responses to CRH, and blunted DST in some patients. All the impairments improved after alprazolam therapy, in parallel with decreases in anxiety and in severity and frequency of panic attacks.

Interleukin-1β and tumor necrosis factor-α in children with major depressive disorder or dysthymia

Background: Immune function is altered in adult depressed patients. The aim of our study was to see whether or not cytokine secretion is impaired at a very young phase of development of depressive disorders, possibly being pathogenetically involved in their course. Methods: Basal plasma concentrations of interleukin-1β (Il-1β) and tumor necrosis factor-α (TNF-α) were measured radioimmunologically in 22 drug-free children–adolescents, 11 with recurrent major depressive disorders (MDD) and 11 with dysthymia (DYS), and in 11 psychophysically healthy age–sex matched controls. Depression was monitored using the Poznanski Rating Scale and Anxiety with the Reynold Rating Scale. Results: Il-1β levels were not significantly different in MDD from controls and significantly higher than normal in DYS subjects. TNF-α levels were not significantly different in MDD patients from controls and significantly lower than normal in DYS patients. Cytokine concentrations were correlated with anxious and depressive symptomatology in MDD but not in DYS patients. Conclusions: There is a cytokine pathology in depressive disorders of obscure etiopathogenetical significance.

Physiological and behavioral responses to minor stressors in offspring of patients with panic disorder

Nineteen children born to patients with panic disorder and a comparison group of 16 children born to unaffected, non-psychiatric patient subjects exposed to novel and mildly stressful situations (visiting an unfamiliar place and watching a movie containing anxiogenic scenes) were assessed for their behaviors, heart rate, respiratory rate and salivary cortisol secretion. At arrival children born to patients with panic disorder had significantly longer latency of first spontaneous verbal comment, fewer prosocial behavior, and increased distress and attachment behavior. During the projection of the movie, children of the two groups differed for attachment, distress, and exploration behaviors. During the anxiogenic scenes children born to patients with panic disorder showed increased behavioral inhibition and higher heart rate. Autonomic modulation, respiratory rates and cortisol secretion were similar in the two groups. Some distinct psychophysiological patterns may constitute early manifestations of the transmitted liability to panic disorder.

A label‐free internal standard method for the differential analysis of bioactive lupin proteins using nano HPLC‐Chip coupled with Ion Trap mass spectrometry

Quantitative proteomics based on MS is useful for pointing out the differences in some food proteomes relevant to human nutrition. Stable isotope label‐free (SIF) techniques are suitable for comparing an unlimited number of samples by the use of relatively simple experimental workflows. We have developed an internal standard label‐free method based on the intensities of peptide precursor ions from MS/MS spectra, collected in data dependent runs, for the simultaneous qualitative characterization and relative quantification of storage proteins of Lupinus albus seeds in protein extracts of four lupin cultivars (cv Adam, Arés, Lucky, Multitalia). The use of an innovative microfluidic system, the HPLC‐Chip, coupled with a classical IT mass spectrometer, has allowed a complete qualitative characterization of all proteins. In particular, the homology search mode has permitted to identify single amino acid substitutions in the sequences of vicilins (β‐conglutin precursor and vicilin‐like protein). The MS/MS sequencing of substituted peptides confirms the high heterogeneity of vicilins according to the peculiar characteristics of the vicilin‐encoding gene family. Two suitable bioinformatics parameters were optimized for the differential analyses of the main bioactive proteins: the “normalized protein average of common reproducible peptides” (N‐ACRP) for γ‐conglutin, which is a homogeneous protein, and the “normalized protein mean peptide spectral intensity” (N‐MEAN) for the highly heterogenous class of the vicilins.

Serotonergic dysfunction across the eating disorders: relationship to eating behaviour, purging behaviour, nutritional status and general psychopathology

BACKGROUND Several recent studies have pointed to a dysfunction of serotonin transmission in patients with eating disorders. Notwithstanding, it is not known whether serotonergic abnormalities are related primarily to eating and/or purging behaviour, nutritional status or general psychopathological dimensions. Therefore, by using a validated neuroendocrine strategy, we investigated central serotonergic function in patients with anorexia nervosa, bulimia nervosa or binge-eating disorder who differ on the above parameters. METHODS Plasma prolactin response to D-fenfluramine (30 mg p.o.) or placebo was measured in 58 drug-free female volunteers, comprising 15 underweight anorexic women, 18 bulimic women, 10 women with binge-eating disorder and 15 female healthy controls. Behavioural assessment included ratings of eating disorder symptoms, depression, aggression and food-related obsessions and compulsions. RESULTS A significantly decreased prolactin response to D-fenfluramine was found in underweight anorexic women and in bulimics with high frequency bingeing ( > 2 binge episodes/day), but not in patients with binge-eating disorder or in bulimics with low frequency bingeing (< I binge episode/day). In the whole bulimic group, a negative correlation emerged between frequency of bingeing and prolactin response. No significant correlation was found between physical or psychopathological measures and the hormonal response in any group. CONCLUSIONS These results confirm our previous findings of an impaired serotonergic transmission in underweight anorexics and in bulimics with high frequency bingeing, but not in patients with less severe bulimia nervosa. Moreover, they show, for the first time, that the hypothalamic serotonergic system is not altered in women with binge-eating disorder.