Dopamine receptor D2 and D4 genes, GABA(A) alpha-1 subunit genes and response to lithium prophylaxis in mood disorders

Lithium is an effective prophylactic agent in mood disorders, and genetic factors are likely to modulate individual susceptibility to lithium treatment. The aim of this study is to investigate the influence of dopamine receptor D2 (DRD2), D4 exon 3 (DRD4), and gamma-aminobutyric acid type A (GABA(A)) receptor alpha-1 subunit (GABRA1) gene variants on the efficacy of lithium prophylaxis in mood disorders. Patients with mood disorders (N = 125: bipolar subtype, n = 100; major depressive disorder subtype, n = 25) were followed prospectively for an average of 53 months and were typed for DRD2 (Ser311/Cys311: n = 121, VNTR: n = 63), DRD4 (n = 125) and GABRA1 (n = 61) variants using polymerase chain reaction (PCR) techniques. DRD2, DRD4 and GABRA1 variants were not associated with response to lithium. A trend was observed toward a better outcome of DRD4* 2/4 subjects, but it was due to only two subjects. Consideration of possible stratification effects like gender, polarity, family history, age at onset and duration of lithium treatment did not reveal any association either. DRD2, DRD4 and GABRA1 variants therefore do not appear to be associated with the outcome of lithium prophylaxis in mood disorders.

Symptomatologic analysis of psychotic and non-psychotic depression

BACKGROUND

The aim of the present study is to evaluate the symptomatologic presentation of delusional compared to non-delusional major depressive episodes.

METHODS

Two hundred and eighty-eight subjects suffering from mood disorder (144 bipolar, 133 unipolar) were assessed at admission by the Hamilton Depression Rating Scale (HAMD-21).

RESULTS

Depressive symptomatology was more severe in the delusional sample, even after the exclusion of the items directly involved with delusional symptoms (P = 0.00002).

CONCLUSIONS

Our data support the hypothesis of delusional depression as a more severe form of mood disorder.

No association between serotonin-2A receptor gene polymorphism and psychotic symptomatology of mood disorders

Abnormalities of the serotonergic system are involved in the pathophysiology of mood disorders. In the present study, we investigated the possible influence of the T102C polymorphism of the serotonin-2A receptor gene (5-HT2A, 13q14-21) on the symptomatology of mood disorders. Inpatients affected by mood disorders (n = 246, 149 bipolar, 97 major depressive disorder) were assessed with a checklist of operational criteria for psychotic illness (OPCRIT) to score their lifetime psychotic symptomatology. The subjects were also typed for 5-HT2A variants using polymerase chain reaction techniques. No association was found between this polymorphism and psychopathology as defined by the four symptomatologic factors used in phenotype definition (mania, depression, delusion and disorganization). Genetic variation at the 5-HT2A receptor gene does not, therefore, appear to play a major role in the pathogenesis of major mood disorders.

Rate of switch from depression into mania after therapeutic sleep deprivation in bipolar depression

Sleep deprivation is a potentially useful non-pharmacological treatment for depression. A relationship between sleep loss and the onset of mania has been reported, so it is possible that a switch from depression into mania after sleep deprivation might be expected in bipolar depressed patients who are treated with sleep deprivation. In a sample of 206 bipolar depressed treated with three cycles of sleep deprivation, alone or in combination with heterogeneous medications, we observed a 4.85% switch rate into mania and a 5.83% switch rate into hypomania. These percentages are comparable to those observed with antidepressant drug treatments.

Social adjustment and self-esteem in remitted patients with mood disorders

Mood disorders are characterized by manic and depressive episodes alternating with normal mood. While social function is heavily impaired during episodes of illness, there are conflicting opinions about inter-episode function. The present paper focuses on self-esteem and social adjustment in remitted mood disorders patients. Patients with mood disorders (99 bipolar and 86 major depressive subjects, in remission) were compared with a group of 100 control subjects. The self-esteem scale (SES) and the social adjustment scale (SAS) were used to measure self-esteem and social adjustment, respectively, in both groups of subjects. Patients with mood disorder exhibited worse social adjustment and lower self-esteem than control subjects. These results strongly confirm previous observations of poor inter-episode function in patients with mooddisorder.

Ongoing lithium treatment prevents relapse after total sleep deprivation

Forty bipolar depressed inpatients underwent three consecutive cycles of total sleep deprivation (TSD). At the beginning of the study, 20 patients were free of psychotropic drugs and 20 had been receiving lithium medication for at least 6 months. Mood was rated on the Hamilton Rating Scale for Depression before and after TSD; perceived mood changes during treatment were evaluated with self-administered visual analog scales. Patients undergoing long-term lithium treatment showed a significantly better response to TSD as rated on both scales: 13 of 20 patients (vs. 2 of 20 patients without lithium) showed a sustained response during a follow-up period of 3 months. This preliminary evidence of a positive interaction of TSD and long-term lithium treatment could be explained by a synergistic effect of both treatments on brain serotonergic function, possibly via a desensitization of 5-hydroxytryptamine-1A inhibitory autoreceptors.

A psychometric-genetic study of schizotypal disorder

This study aimed to clarify the structure and the etiological constituents of schizotypal disorder (SPD) by directly interviewing pairs of twins. A latent class analysis was applied to each individual's outcome for specified SPD items, such that each subject's phenotype could be redefined in terms of individual probabilities of class membership. Intraclass correlations were then calculated for each twin pair, and a standard univariate twin model applied. The best latent class analysis solution encompassed a model with four latent classes (three latent classes of SPD subjects, one of non-SPD). The intraclass correlations revealed a moderate to high heritability for two out of three SPD classes and for the modal class (a class composed of subjects that possessed a conditional probability of belonging to any of the SPD classes). Model fittings revealed considerable variation in the extent to which the different classes of SPD were influenced by additive genetic constituents or non-genetic factors. Although these data confirm the importance of genetic contributors in determining liability to SPD and the schizophrenia spectrum, they indicate that there is a relationship between psychometric multidimensionality and etiological heterogeneity in SPD.

Serotonin transporter gene (5-HTTLPR) is not associated with depressive symptomatology in mood disorders

Disturbances of the serotoninergic neutrotransmitter system have been implicated in the pathogenesis of mood disorders. A functional polymorphism in the upstream regulatory region of the serotonin transporter gene (5-HTTLPR) has been recently reported to be associated with both unipolar and bipolar disorder. In this study, we investigated the possibility that the 5-HTTLPR might be associated with depressive symptomatology in a sample of mood disorder subjects. One hundred and thirty-two psychiatric inpatients affected by major depressive (n = 67) and bipolar (n = 65) disorder (DSM-IV) were assessed at admission by the Hamilton Depression Rating Scale (HAMD-21, divided into Core, Sleep, Activity, Psychic anxiety, Somatic anxiety and Delusion clusters) and were typed using PCR techniques. The only prior treatment permitted was low dose benzodiazepines (<5 mg diazepam or equivalent); no prior (<2 weeks) antidepressant or neuroleptic treatment was allowed. 5-HTTLPR variants were not associated with total depressive symptomatology as measured by HAMD. The short 5-HTTLPR variant was marginally associated with higher psychic anxiety scores (F = 7.11, d.f. = 1,262, P = 0.008). The association was stronger among bipolars and early onset subjects. 5-HTTLPR variants were not associated with the remaining symptom clusters. The upstream regulatory region of the serotonin transporter gene has not, therefore, a major influence on the depressive symptomatology in mood disorder subjects.

Serotonin transporter gene not associated with psychotic symptomatology of mood disorders

A functional polymorphism in the upstream regulatory region of the serotonin transporter gene (5-HTTLPR) has been recently reported to be associated with mood disorders. In the present study we investigated the possible influence of 5-HTTLPR on the symptomatology of mood disorders. Two hundred and thirty inpatients affected by mood disorders (160 bipolar and 70 major depressive disorder) were assessed by the Operational Criteria checklist for psychotic illness (OPCRIT) and were also typed for the 5-HTTLPR variants using PCR techniques. Mania, Depression, Delusion and Disorganization were the four symptomatologic factors used as phenotype definition. 5-HTTLPR variants were not associated with these symptomatologic factors, and consideration of possible stratification effects, such as sex, age of onset and polarity, did not reveal any association either. The serotonin transporter gene does not, therefore, appear to be associated with the symptomatology of mood disorders.

Sustained antidepressant effect of sleep deprivation combined with pindolol in bipolar depression. A placebo-controlled trial

Total sleep deprivation (TSD) shows powerful but transient clinical effects in patients affected by bipolar depression. Pindolol blocks the serotonergic 5-HT1A autoreceptor, thus improving the antidepressant effect of selective serotonin reuptake inhibitors. We evaluated the interaction of TSD and pindolol in the treatment of acute episodes of bipolar depression. Forty bipolar depressed inpatients were randomized to receive pindolol 7.5 mg/day or placebo for nine days in combination with three consecutive TSD cycles. Pindolol significantly improved the antidepressant effect of TSD, and prevented the short-term relapse after treatment. The response rate (HDRS scores < 8) at the end of treatment was 15/20 for pindolol, and 3/20 for placebo. Coadministration of pindolol and TSD resulted in a complete response, which could be sustained for six months with lithium salts alone, in 65% of cases. This results suggest a major role for serotonergic transmission in the mechanism of action of TSD, and makes TSD treatment more effective in the treatment of bipolar depression.

Abnormalities of cyclic adenosine monophosphate signaling in platelets from untreated patients with bipolar disorder

BACKGROUND

Abnormalities in the cyclic adenosine monophosphate (cAMP)-dependent phosphorylation system have been recently reported in patients with bipolar disorder. We evaluated the immunoreactivity of the regulatory and catalytic subunits of cAMP-dependent protein kinase (protein kinase A) and 1 of its substrates, Rap1, in platelets from untreated euthymic, manic, and depressed patients with bipolar disorder and healthy subjects.

METHODS

Platelets were collected from 112 drug-free patients with bipolar disorder (52 euthymic, 29 depressed, and 31 manic) and 62 healthy subjects. The levels of cAMP-dependent protein kinase and Rap1 were assessed by Western blot analysis, immunostaining, and computer-assisted imaging.

RESULTS

The immunolabeling of the catalytic subunit of cAMP-dependent protein kinase was significantly different among groups (P<.001), with higher values in untreated depressed and manic patients with bipolar disorder compared with untreated euthymic patients with bipolar disorder and healthy subjects. No significant differences were found in the immunolabeling of the regulatory subunits (type I and type II) of cAMP-dependent protein kinase. The immunolabeling of Rap1 was significantly higher (P<.001) in untreated euthymic, depressed, and manic patients than in healthy persons.

CONCLUSIONS

Levels of Rap1 and the catalytic subunit of cAMP-dependent protein kinase are altered in the platelets of bipolar patients. These findings may provide clues toward understanding the involvement of cAMP signaling in the pathogenesis of bipolar disorder.

Factor analysis of delusional disorder symptomatology

Delusional disorder symptomatology has been poorly investigated with factor analytic studies. Most attempts to identify its symptomatologic structure were made with schizophrenic or mixed psychotic populations and included only delusional symptoms. The purpose of this study was to analyze the whole symptomatologic structure of delusional disorder. One hundred eight inpatients with delusional disorder (DSM-III-R) were evaluated for lifetime symptoms using the Operational Criteria (OPCRIT) checklist for psychotic illness and included in a factorial analysis. Four factors were evaluated: (1) core depressive symptoms, (2) hallucinations, (3) delusions, and (4) irritability symptoms. Thus, when scored by the OPCRIT checklist, delusional symptomatology consisted of four independent factors, indicating a substantial heterogeneity of this diagnostic category.

Complex segregation analysis for obsessive compulsive disorder and related disorders

Complex segregation analysis was applied to a sample of 107 Italian families with probands with obsessive compulsive disorder (OCD), using regressive logistic models to test for possible models of genetic transmission. We used two different phenotypic definitions of affection: 1) OCD; and 2) OCD plus Tourette's syndrome/chronic motor tics (CMT). Because of the potential relationship between OCD, Tourette's syndrome (TS), and other tic disorders, we considered these diagnoses to be determined by the same liability in subsequent steps of the analysis. For the 107 OCD families, the best fit was a dominant model of transmission (with a higher penetrance for females). When the phenotype boundaries were widened (OCD + CMT + TS), an unrestricted model of transmission became the best fit. We concluded that additional data are needed to support the hypothesis that Tourette's syndrome and OCD share a common etiology: on the basis of clinical and epidemiological considerations, the OCD phenotype probably presents a higher level of heterogeneity than the TS phenotype, and it could be regulated through different etiologic pathways.

No interaction of GABA(A) alpha-1 subunit and dopamine receptor D4 exon 3 genes in symptomatology of major psychoses

Previously, we reported on an association of the dopamine receptor D4 (DRD4) gene with delusional symptomatology of major psychoses. However, despite the strength of the association, it only accounted for 2% of the variance, indicating that contributions from other genes were probable. In the present study, we investigated the original cohort of subjects to evaluate the gene for the gamma-aminobutyric acid type A (GABA(A)) receptor alpha-1 subunit (GABRA1). The possible association of GABRA1 with the psychopathology of major psychoses was tested both alone and in interaction with DRD4. Four hundred and sixty-one inpatients affected by major psychoses were assessed by the operational criteria checklist for psychotic illness (OPCRIT) and were also typed for the DRD4 and GABRA1 variants using PCR techniques. Mania, depression, delusion, and disorganization were the four symptomatologic factors used as phenotype definitions. GABRA1 variants were not associated with these symptomatologic factors, and consideration of possible stratification effects such as sex and psychiatric diagnosis also did not reveal any association. GABRA1 variants did not significantly influence the association of DRD4 with delusional symptoms. No interaction was observed on the other symptom factors. The GABA(A) alpha-1 subunit gene does not, therefore, interact with DRD4 in the symptomatology of major psychoses.

Serotonin transporter gene is not associated with symptomatology of schizophrenia

The serotonin transporter gene is a primary candidate for involvement in major psychoses. A functional polymorphism in the upstream regulatory region of the serotonin transporter gene (5-HTTLPR) has recently been reported to be associated with a variety of psychopathological conditions. In the present study, we investigated the potential influence of the 5-HTTLPR on the psychopathology of schizophrenia. One hundred and sixty-one inpatients affected by schizophrenia (DSMIII-R) were assessed by the Operational Criteria checklist for psychotic illness (OPCRIT) and were typed for their 5-HTTLPR variants by PCR techniques. Mania, Depression, Delusion and Disorganization were the four symptomatologic factors used to define phenotype. 5-HTTLPR variants were not associated with these symptomatologic factors, and consideration of possible stratification effects such as sex, and age of onset did not reveal any association either. The serotonin transporter gene is not a liability factor for the symptomatology of schizophrenia.

Worsening of delusional depression after sleep deprivation: case reports

Five patients (three bipolars and two unipolars) affected by a major depressive episode with psychotic features were treated with total sleep deprivation (TSD) without concurrent psychotropic medication. After TSD we observed a worsening in psychotic as well as in depressive symptoms as rated on the Dimension of Delusional Experience Rating Scale and on Hamilton Rating Scale for Depression, respectively. TSD is known to markedly enhance the activity of brain monoaminergic pathways. Given the interaction between brain serotonergic and dopaminergic systems in delusional depression, it is possible that an enhancement in dopaminergic activity may be responsible of the symptomatological worsening in delusional depressives observed after TSD.

GABAA alpha-1 subunit gene not associated with depressive symptomatology in mood disorders

Considerable evidence implicates the neurotransmitter gamma-aminobutyric acid (GABA) in the biochemical pathophysiology of mood disorders. In this study, we investigated the possibility that the gene for the gamma-aminobutyric acid type A (GABAA) receptor alpha-1 subunit (GABRA1) might be associated with depressive symptomatology in a sample of mood disorder subjects. Sixty-seven inpatients affected by unipolar (n = 37) and bipolar (n = 30) disorder (DSMIV) were assessed at admission by the Hamilton depression rating scale (HAMD) and were typed using polymerase chain reaction (PCR) techniques. GABRA1 variants were not associated with depressive symptomatology, and consideration of possible stratification effects such as sex, psychiatric diagnosis and illness severity did not reveal any association either. GABAA alpha-1 subunit gene is not, therefore, associated with depressive symptomatology in mood disorder subjects.

Faster onset of action of fluvoxamine in combination with pindolol in the treatment of delusional depression: a controlled study

This double-blind, controlled study was undertaken to investigate whether the addition of pindolol could improve the therapeutic response to fluvoxamine of depressed patients with psychotic features. After a 1-week placebo run-in period, 72 patients received fluvoxamine 300 mg/day in combination with placebo or pindolol 7.5 mg/day. At study completion, 28 (80%) of 35 patients treated with fluvoxamine plus placebo and 29 (80.5%) of 36 patients treated with fluvoxamine plus pindolol were categorized as responders (reduction of their score on the 21-item Hamilton Rating Scale for Depression to 8 or less and on the Dimension for the Delusional Experience Rating Scale to 0). In the third and fourth weeks, the response rates were significantly superior in the fluvoxamine plus pindolol group (p = 0.0001, p = 0.023, respectively). Treatment response seemed to be unrelated to the demographic and the clinical characteristics recorded. No significant difference was found comparing plasma levels of fluvoxamine between groups, thus excluding a pharmacokinetic interaction. Other than mild nausea and sedation in a few patients, treatments were well tolerated. No medically significant adverse events occurred. Depressed patients with psychotic features who were administered pindolol experienced a more rapid improvement during fluvoxamine treatment. Thus, the combination of fluvoxamine with pindolol may be a useful pharmacologic strategy in the treatment of this disorder. A rapid clinical response in such patients is of relevance in clinical practice as well as in economic fields, given the direct and indirect costs of depression.

Mode of inheritance in mood disorder families according to fluvoxamine response

Mood disorders are known to cluster within families, but the mode of transmission remains largely unknown. The purpose of our analysis was to determine whether selection of a sample that was homogeneous in its response to an antidepressant provided stronger evidence for a single major locus. Complex segregation analysis was applied to a sample of 171 Italian families of bipolar and unipolar probands that were responsive to the antidepressant fluvoxamine. We used regressive logistic analyses to determine the best fit from among environmental, arbitrary Mendelian, dominant, recessive and additive models. For the 171 affective families with probands that were responsive to the antidepressant fluvoxamine, a Mendelian model of inheritance was rejected. When considering 68 families of bipolar probands, the best fit was obtained for a Mendelian dominant model of transmission. The identification of a Mendelian mode of transmission in bipolar subjects who were selected according to their response to fluvoxamine supports the use of a pharmacological criterion as a tool for identifying true genetic disorders.

Dopamine receptor D2 Ser/Cys311 variant associated with disorganized symptomatology of schizophrenia

The dopamine D2 receptor gene has been proposed as a genetic risk factor for schizophrenia (Arinami et al., 1994). However, a number of replications failed to confirm the initial report. The finding of a stronger association considering schizophrenics with the absence of negative symptoms (Arinami et al., 1996) suggested that the influence of DRD2 variants should be analyzed more at the level of symptoms rather than syndromes. One hundred and four inpatients affected by schizophrenia (n = 99) and delusional disorder (n = 5) (DSM IV) were assessed at admission by the Operational Criteria for Psychotic Illness (OPCRIT) and were typed for DRD2 variants using polymerase chain reaction (PCR) techniques. Subjects with the S311C variant presented a higher score on the 'Disorganization' factor (P = 0.012). Consideration of possible stratification effects such as sex and age of onset did not reveal any deviation from the whole sample. In conclusion, our preliminary report suggests that the DRD2 S311C variant may be a liability factor for disorganized symptoms among schizophrenics or for a subtype of schizophrenia characterized by highly disorganized symptomatology.

Polymorphism within the promoter of the serotonin transporter gene and antidepressant efficacy of fluvoxamine

Depression with psychotic features has been shown to respond to selective serotonin reuptake inhibitors (SSRIs). The serotonin transporter (5-HTT) is a prime target for SSRIs. A functional polymorphism within the promoter region of the 5-HTT gene, leading to different transcriptional efficiency, was recently reported. We tested the hypothesis that allelic variation of the 5-HTT promoter could be related to the antidepressant response to fluvoxamine and/or augmentation with pindolol (a serotonin autoreceptors antagonist) which has been suggested as an augmentation therapy for nonresponders. One hundred and two inpatients with major depression with psychotic features were randomly assigned to treatment with a fixed dose of fluvoxamine and either placebo or pindolol for 6 weeks. Depression severity was assessed once a week using the Hamilton Depression Rating Scale. Allelic variation in each subject was determined using a PCR-based method. Data were analyzed with a three-way repeated measures analysis of variance. Both homozygotes for the long variant (l/l) of the 5-HTT promoter and heterozygotes (l/s) showed a better response to fluvoxamine than homozygotes for the short variant (s/s). In the group treated with fluvoxamine plus pindolol all the genotypes acted like l/l treated with fluvoxamine alone. Fluvoxamine efficacy in delusional depression seems to be related to allelic variation within the promoter of the 5-HTT gene. Even though other factors may be implicated, genotyping at 5-HTT promoter may represent a promising tool to individualize the pharmacological treatment of depression.

Perceived mood and skin body temperature rhythm in depression

Eighteen inpatients affected by recurrent major depression were monitored in their clinical and biological features during the acute episode of illness. Diurnal mood variations rated with Visual Analogue Scale (VAS) and diurnal variations of skin body temperature were measured every 2 h consecutively for 2 days. Circadian rhythmicity of the two parameters was evaluated by cosinor analysis separately for each patient. The inspection of the individual cosine fitting shows that patients with a high circadian rhythmicity in perceived severity of symptomatology tend to show low circadian rhythmicity in skin body temperature, whereas patients with a low VAS oscillation tend to display a higher diurnal variation in skin body temperature. A chi-square test confirmed a statistical significance of the discordance between the two rhythms. We discuss our findings hypothesizing a different degree of entrainment of the disease process to the main circadian pacemaker.

Effects of lithium on cAMP-dependent protein kinase in rat brain

We have investigated the effects of lithium treatment on cAMP-dependent protein kinase in discrete brain areas of rat by using photoaffinity labeling as well as western blotting. Lithium administered for 5 weeks resulted in a significant increase of the cAMP binding to the 52 kDa cAMP-receptor in the soluble, but not in the particulate, fractions of both hippocampus and frontal cortex. Moreover, immunoblotting experiments revealed that chronic lithium treatment significantly increased the immunoreactivity against the regulatory and the catalytic subunits of the cAMP-dependent protein kinase in the soluble fraction of both brain areas. In contrast, no appreciable effect was observed in the particulate fractions. Short-term lithium treatment induced a significant increase in the immunolabeling of the catalytic subunits in the soluble fraction of both areas; whereas, the regulatory subunits and the actin were unchanged. In the particulate fractions, short-term lithium treatment did not elicit any substantial modification. Taken together, the results of the present study add to the growing evidence indicating that components of the cAMP signalling could play a crucial role in the biochemical action of lithium.

Familial concordance of fluvoxamine response as a tool for differentiating mood disorder pedigrees

Concordance to antidepressant response in members of the same family is a common observation in clinical practice. However, few published data support this view; moreover families with affected members responder to the same antidepressant have been poorly studied. We have analyzed 45 pairs consisting of one mood disorder fluvoxamine double-responder proband and one first-degree relative with known outcome to fluvoxamine treatment. Among 45 pairs 30 (67%) were concordant for good response to fluvoxamine. In family pedigrees of concordant pairs we found a significantly higher distribution of bipolar forms in secondary cases than in families of non concordant pairs (14.9% vs 3.9% P = 0.039) suggesting that concordance to antidepressant therapy could select families with higher genetic loading.