Biomedical subjects

Cristina Colombo

Publications and source records attributed to Cristina Colombo.

26 records · Page 2Linked to original sources

PubMed2003

Influence of CLOCK gene polymorphism on circadian mood fluctuation and illness recurrence in bipolar depression.

Recent studies showed that a polymorphism (T to C nucleotide substitution) in the 3' flanking region of the human CLOCK gene is associated with diurnal preferences of human healthy subjects, with higher "eveningness" in subjects carrying at least one copy of the C allele. We investigated the possible role of CLOCK gene polymorphism in the regulation of diurnal mood fluctuations during a major depressive episode. Sample (n = 101) was collected, in the context of previously reported trials, among patients affected by bipolar disorder type I, depressive episode without psychotic features, free of psychotropic medications. Perceived mood levels were assessed three times a day with self-administered visual analogue scales. Genotype groups showed no significant difference in diurnal mood fluctuations. When stratifying the sample by including only patients with an adequate period of observation (duration of illness higher than 5 years, n = 69), we post-hoc observed a significantly higher recurrence rate in homozygotes for the C variant, which was almost double than that of the other genotype groups. This preliminary observation leads to hypothesize a role for the CLOCK gene polymorphism in the regulation of long-term illness recurrence in bipolar disorder. Given the post-hoc nature of the finding, replication in independent samples is necessary to confirm it.

Bipolar Disorder↗

PubMed2003

Antidepressant effects of light therapy combined with sleep deprivation are influenced by a functional polymorphism within the promoter of the serotonin transporter gene.

BACKGROUND: A functional polymorphism within the promoter of the serotonin transporter has been shown to influence the antidepressant response to serotonergic drug treatments and to total sleep deprivation (TSD). The short-term relapse that follows acute response to TSD has been successfully prevented by combining TSD with light therapy. The mechanism of action of this combined treatment is unknown. METHODS: We tested the hypothesis that allelic variation of the serotonin transporter (5-HTT) linked polymorphic region (5-HTTLPR) could influence the response to the combination of light therapy and TSD. Twenty-two bipolar depressed inpatients were administered a night of TSD combined with 30 min light therapy given during the TSD night and in the morning after recovery sleep. 5-HTTLPR was genotyped using polymerase chain reaction techniques. Changes in perceived mood were rated on a visual analog scale. RESULTS: Light therapy sustained the effect of TSD. The effect was more marked in homozygotes for the long variant of 5-HTTLPR than in heterozygotes and homozygotes for the short variant. CONCLUSIONS: The influence of 5-HTTLPR on response to the combination of TSD and light therapy is similar to that observed on response to TSD and serotonergic drug treatments.

Adult↗

PubMed2003

Genetic dissection of psychopathological symptoms: insomnia in mood disorders and CLOCK gene polymorphism.

We investigated the possible effect of the 3111T/C CLOCK gene polymorphism on sleep disorders in a sample of 620 patients affected by major depressive disorder (MDD) and bipolar disorder (BP). We detected a significantly higher recurrence of initial (P = 0.0001), middle (P = 0.0009), and early (P = 0.0008) insomnia in homozygotes for the C variant and a similar trend concerning decreased need of sleep in BP (P = 0.0074). Other demographic and clinical features were found not related with CLOCK polymorphisms. This preliminary observation leads to hypothesize a possible involvement of the CLOCK gene polymorphism in the sleep disregulations in MDD and BP.

Adult↗

PubMed2003

Dopamine receptor D2 and D3 gene variants are not associated with the antidepressant effect of total sleep deprivation in bipolar depression.

Total sleep deprivation (TSD) is an effective treatment for mood disorders that is thought to act through an enhancement in several neurotransmitter pathways including dopaminergic transmission. Genetic factors are likely to play a major role in determining individual differences in TSD response. The aim of this study is to investigate the influence of dopamine receptor D3 (DRD3) and dopamine receptor D2 (DRD2) variants on TSD antidepressant efficacy in bipolar disorder. One hundred twenty-four depressed inpatients affected by bipolar disorder (DSM-IV) were treated with TSD and were genotyped for DRD3 first exon Gly/Ser variants and DRD2 codon 311 Ser/Cys variants using polymerase chain reaction techniques. DRD3 and DRD2 variants were not associated with TSD outcome. Consideration of possible stratification effects such as gender, age at onset and duration of illness did not reveal any association either. The tested gene variants are not a main factor influencing TSD outcome in bipolar disorder.

Adult↗

PubMed2003

5-HT(2A) receptor binding is reduced in drug-naive and unchanged in SSRI-responder depressed patients compared to healthy controls: a PET study.

OBJECTIVE: The aim of the study was to investigate differences in 5-HT(2A) receptor binding between healthy volunteers and patients with major depressive disorder (MDD), either never treated before with antidepressants (drug-naive: DN) or responding to paroxetine treatment (drug-treated: DT). METHODS: Nineteen DN patients with MDD and 15 euthymic DT (paroxetine 4 weeks) patients were compared with a group of 20 healthy controls (C) with positron emission tomography (PET) using [(18)F]fluoroethylspiperone ([(18)F]FESP), a 5-HT(2A) and D(2) receptor antagonist. A "binding index" (BI) of [(18)F]FESP to cortical and basal ganglia regions was calculated as the ratio of the activity in these regions to that of cerebellum. Differences in BI between groups, i.e. C versus DN or DT, were assessed by ANOVA, with or without age as covariate (ANCOVA). RESULTS: A significant reduction in BI ( P=0.003 ANOVA, P=0.001 ANCOVA) was found in DN patients in the frontal, occipital, temporal and cingulate cortices, but not in the striatum. No significant differences emerged between C and DT patients. CONCLUSIONS: The reduction of [(18)F]FESP BI in cortical areas of DN depressed, but not of euthymic DT patients suggests an association between the occurrence of depressive symptoms and impairment of cortical 5-HT(2A) receptors. [(18)F]FESP cortical BI may represent a state marker of depression.

Adult↗

PubMed2003

Dopaminergic modulation of apoptosis in human peripheral blood mononuclear cells: possible relevance for Parkinson's disease.

Dopamine (DA) modulates apoptosis in neuronal and non-neuronal cells, and dopaminergic pathways contribute to neurodegenerative disease. Human lymphocytes express dopaminergic receptors and DA transporters, and synthesize endogenous catecholamines, which may modulate apoptosis in these cells. In the present study, dopaminergic modulation of apoptosis was investigated in human peripheral blood mononuclear cells (PBMCs) obtained from healthy donors. Twenty-four-hour DA reduced at 0.1-5 x 3 10(-6) M and enhanced at 1-5 x 310(-4) M spontaneous apoptosis. DA 1 x 310(-6) M was inhibited by the D1-like receptor antagonist SCH 23390 1 x 310(-6) M, but not by the D2-like receptor antagonists domperidone 1 x 3 10(-6) M or haloperidol 1 x 3 10(-6) M, while the effect of DA 5 x 3 10(-4) M was prevented by the antioxidants glutathione 5-10 mM or N-acetyl-l-cysteine 1-10 mM. Intracellular reactive oxygen species were respectively reduced and increased by 1-3 h incubation with DA 0.1-10 x 3 10(-6) M and 1-5x310(-4) M. Twenty-four-hour DA 1 x 3 10(-6) M or 5 x 3 10(-4) M had no effect on PBMC expression of Cu/Zn superoxide dismutase or Bcl-2; however, DA 5 x 3 10(-4) M decreased caspase-3 activity. In human PBMCs, DA seems to promote apoptosis through oxidative mechanisms but may also result in cell rescue from apoptotic death possibly through activation of D1-like receptors. The dual effect of DA on human PBMCs closely resembles that on striatal neurons. Lymphocytes of patients with Parkinson's disease may show reduced DA content and impaired DA transporter immunoreactivity. Human PBMCs may thus represent a simple and readily accessible model to study DA-related mechanisms relevant for neurodegenerative disease.

Apoptosis↗

PubMed2003

Morning light treatment hastens the antidepressant effect of citalopram: a placebo-controlled trial.

BACKGROUND: Selective serotonin reuptake inhibitors are effective in approximately 70% of patients with a major depressive episode, but therapeutic changes usually require 2 weeks of administration to become clinically relevant. Adjunct light therapy has been proposed to hasten the effects of drug treatment. The purpose of the present study was to evaluate the effect of morning light therapy or placebo combined with citalopram in the treatment of patients affected by a major depressive episode without psychotic features. METHOD: Thirty inpatients (DSM-IV major depressive disorder [N = 21] and bipolar disorder [N = 9]) were treated with citalopram, 40 mg, and randomized in a 3:2 manner to receive 30 minutes of 400 lux green light treatment in the morning or placebo (exposure to a deactivated negative ion generator) during the first 2 weeks of drug treatment. Timing of light therapy was individually defined to obtain a 2-hour phase advance to morning light. Outcome was measured with the Hamilton Rating Scale for Depression and the Zung Self-Rating Depression Scale every week, and with a Visual Analogue Scale 3 times a day during the first week. RESULTS: All outcome measures showed significantly (p <.05) better mood improvement in light-treated patients, resulting in faster responses to antidepressant treatment. CONCLUSION: The combination of citalopram and light treatment was more effective than citalopram and placebo in the treatment of major depression. With an optimized timing of administration, low-intensity light treatment significantly hastened and potentiated the effect of citalopram, thus providing the clinical psychiatrists with an augmenting strategy that was found effective and devoid of side effects.

Circadian Rhythm↗

PubMed2002

Interleukine-6 serum levels correlate with response to antidepressant sleep deprivation and sleep phase advance.

Unstimulated production of interleukine-6 (IL-6) is known to be enhanced in patients affected by a major depressive episode. Recent studies supported a role for basal IL-6 levels in predicting response to antidepressant drug treatments. In a sample of 10 consecutively admitted drug-free bipolar depressed inpatients, we investigated the possible correlation between unstimulated pretreatment production of IL-6 and antidepressant response to a night of total sleep deprivation (TSD) followed by a night of sleep phase advance (SPA), a nonpharmacologic treatment which is known to rapidly improve depressive symptomatology. Changes in perceived mood during treatment were recorded with self-administered Visual Analogue Scales (VAS). We observed a significant inverse correlation between IL-6 serum levels and VAS scores after treatment, meaning that higher IL-6 values before treatment were associated with worse response. This finding is in agreement with previous studies about amitriptyline and lithium antidepressant treatments. Our preliminary finding confirms the clinical value of IL-6 baseline concentration as a predictor of response to antidepressant treatment.

Adult↗