Maria Cristina Baroni

Neuroendocrine correlates of depression in abstinent heroin-dependent subjects

The functions of the central alpha-adrenergic, serotoninergic and dopaminergic systems were investigated in 28 heroin-dependent subjects 6-8 weeks after detoxification, and in 22 healthy control subjects (group C). Fourteen heroin-dependent subjects with depressive comorbidity (group A), and 14 heroin-dependent subjects without other Axis I and II pathologies (group B) were included among abstinent substance abusers. Norepinephrine (NE) function was evaluated by growth hormone (GH) responses to acute stimulation with clonidine (clon); serotonin (5-HT) function by prolactin (PRL) and cortisol (CORT) responses to acute stimulation with D-fenfluramine (D-fen) and dopamine (DA) function by GH and PRL responses to acute administration of bromocriptine (brom). Central NE activity, as measured by the GH-clon test, seems to be well preserved both in A and B subjects. PRL and CORT responses to D-fen were significantly blunted both in A subjects and in B subjects, in comparison with control subjects (C); the PRL response in A subjects was significantly lower than in B subjects. The DA system of B subjects was found unimpaired; in contrast, a significantly higher GH response to brom in A subjects (depressed) could express D2 post-synaptic receptor hypersensitivity and, therefore, decreased pre-synaptic DA release. In sum, the study of central monoamine function revealed an alteration only of the 5-HT system in detoxified heroin-dependent subjects without psychiatric comorbidity, which might be a trait character of these subjects, possibly involved in the pathogenesis of the disorder. A more significant impairment of 5-HT function and the hypersensitivity of post-synaptic DA receptors in A subjects suggests that specific biological correlates of psychiatric comorbidity may characterize substance abuser subtypes.

Serum CXCL10 levels and occurrence of thyroid dysfunction in patients treated with interferon-α therapy for hepatitis C virus-related hepatitis

OBJECTIVE Thyroid autoimmunity is a common side effect of interferon-alpha (IFN-alpha) treatment for chronic hepatitis C. There are currently no reliable parameters to predict the occurrence of thyroid dysfunctions in patients undergoing IFN-alpha therapy. CXC chemokine ligand 10 (CXCL10) is a chemokine known to play a role in both thyroid autoimmune disease and hepatitis C virus (HCV) hepatitis. DESIGN The aim of this study was to evaluate serum CXCL10 levels in HCV patients treated with IFN-alpha in relation to the occurrence of thyroid dysfunctions. Serum CXCL10 levels were assayed in 25 HCV patients (proven to be negative for serum thyroid antibodies) before and during IFN-alpha therapy (2, 4 and 6 months) and in 50 healthy controls. HCV patients were retrospectively selected according to the occurrence of IFN-alpha-induced thyroid dysfunction and were assigned to two groups. Group I included 15 patients who did not develop thyroid antibody positivity or dysfunction; group II included ten patients who showed the appearance of serum thyroid antibodies, followed by clinically overt thyroid dysfunction. RESULTS Patients with HCV, regardless of the development of thyroid dysfunctions, had significantly higher serum CXCL10 than controls (261.6+/-123.4 vs 80.4+/-33.6 pg/ml; P<0.00001). Pretreatment mean serum CXCL10 levels were significantly higher in Group I versus Group II (308.6+/-130.7 vs 191.1+/-69.4 pg/ml; P<0.05). Groups I and II showed different rates of favourable response to IFN-alpha treatment (33 and 90% respectively). CONCLUSION Our results suggest that measuring serum CXCL10 before IFN-alpha treatment may be helpful for identifying those patients with higher risk to develop thyroid dysfunction, and require a careful thyroid surveillance throughout the treatment.

Pulmonary Complications in Diabetes Mellitus: The Role of Glycemic Control

Insulin deficiency induces an increase in blood glucose levels that, in long run, becomes toxic for many organs and systems. Microangiopathy and derangements in the immune function are known consequences of hyperglycemia, but the way in which these systemic alterations may affect pulmonary function has been scarcely investigated. Although confirmation from large clinical trials is still to come, the diabetic disease seems to hit the pulmonary microcirculation as any other organ by increasing vessel wall thickness and impairing gas exchange, which leads to a measurable loss of function and respiratory efficiency. In addition, a diabetic lung is more susceptible to low respiratory tract infections by atypical microorganisms and more likely to host severe episodes of pneumonia than a normal, non-diabetic lung. This is a review of current knowledge on the impact of diabetes mellitus in lung health. We have paid special attention to the role of metabolic control in preventing damage to the lung by sustained hyperglycemia.

Pivagabine effects on neuroendocrine responses to experimentally-induced psychological stress in humans

Neuroendocrinology of chronic stress seems to be characterized by HPA axis hyperactivity and early childhood stressors have been hypothesized to predispose individuals to adult onset depression by means of dysregulation of the HPA axis. Pivagabine (PVG), a hydrophobic 4-aminobutyric acid derivative, has been used experimentally recently in the treatment of different disorders related to stress-maladaptation, because of its possible inhibitory action on corticotrophin releasing factor secretion and HPA axis function. In the present study, 20 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) and cortisol (CORT), heart rate (HR) and systolic blood pressure (SBP) were measured immediately before the beginning of the tests and at their end, 30 min later, on both experimental days. Utilizing a double blind schedule, the subjects received pivagabine (900 mg, twice a day)(PVG group: nine subjects) or placebo (PBO group: 11 subjects) during the 7 days between the two stress sessions. NE, EPI, ACTH, and CORT levels were significantly elevated after stress exposure on day 1 and day 8 in PBO group subjects. After PVG treatment, on day 8, ACTH, CORT, NE and EPI responses to stress were significantly blunted, together with HR and SBP, in PVG group subjects. These results add to the evidence concerning PVG capacity to inhibit the HPA axis in humans, in response to stressful stimuli, and suggest that the action of PVG may be mediated not only by GABAergic receptors, but also by the suppression of catecholamines response. PVG treatment could modulate HPA hyper-responsiveness to stress in subjects with negative affectivity and depressive traits.

Maintenance of renal function in a patient with a history of acute paroxysmal nocturnal hemoglobinuria-associated kidney injury

Abstract Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, life-threatening blood disorder characterized by intravascular hemolysis, thrombosis and bone marrow failure. Acute kidney injury, including acute renal failure, have been reported in patients with PNH. We report the case of a 36-year-old male patient with PNH who developed acute kidney injury following an infection of undetermined diagnosis. Although hemolysis was initially controlled and renal function stabilized following packed red blood cell transfusion and empirical levofloxacin and prednisone, he later experienced recurrent episodes of hemolysis and hematuria requiring monthly red blood cell support. Given the high risk of thromboembolic events, treatment with standard-dose eculizumab was started. The patient’s hematologic values improved, renal function was maintained, and no thromboembolic events occurred.