A novel antipsychotic, perospirone, has antiserotonergic and antidopaminergic effects in human brain: findings from neuroendocrine challenge tests

Therapeutic drug monitoring of perospirone: The lowest effective plasma concentration in patients with schizophrenia

OBJECTIVES

This study investigated the effects of demographic factors such as age, sex and comedications on the plasma concentrations of perospirone in individuals diagnosed with schizophrenia. Additionally, the relationship between these plasma levels and the clinical efficacy of the medication was explored.

METHODS

Data regarding the plasma concentration of perospirone in patients with schizophrenia were obtained from the Xi'an Mental Health Center and were retrospectively analysed.

RESULTS

The study results revealed a range of 0.50-1.59 ng/mL for the 25th-75th percentile of perospirone concentration in the plasma, which ranged from 0.07 to 6.0 ng/mL. The plasma concentration of perospirone increased with the daily oral dose (r = 0.283, P < 0.05). Furthermore, patients with higher plasma perospirone concentrations and concentration-to-dose ratios (C/D) tended to be older or were women. Notably, the coadministration of valproate significantly reduced perospirone concentration and the C/D ratio by 54.7% and 35.3%, respectively (P < 0.01). Receiver operating characteristics curve analyses revealed that patients exhibited a good clinical response when their plasma perospirone concentrations were ≥ 1.17 ng/mL.

CONCLUSION

The findings suggest that therapeutic drug monitoring of perospirone and adjustments to achieve steady-state concentrations of ≥ 1.17 ng/mL can be beneficial for optimising treatment for patients with schizophrenia.

Psychotropics and Male Reproduction

Psychotropic drugs, including antidepressants, antipsychotics, and anticonvulsants, all have negative effects on sexual function and semen quality. These adverse events vary among men and are less pronounced for some medications, allowing their effects to be managed to some extent. Use of specific serotonin reuptake inhibitors (SSRIs) is prevalent in men of reproductive age; and application to treat premature ejaculation increases the number of young men on SSRI therapy. Oxidative damage to sperm can result from prolonged residence in the male reproductive tract. The increase in ejaculatory latency seen with SSRIs likely underlies some of their negative effects on semen quality, including higher sperm DNA fragmentation, seen in all SSRIs evaluated thus far. These medications increase prolactin (PRL) levels in some men, and this is often credited with inhibitory effects on male reproduction; however, testosterone levels are generally normal, reducing the likelihood of direct HPG axis inhibition by PRL. The tricyclic antidepressants have also been shown to increase PRL levels in some studies but not in others. The exception is the tricyclic antidepressant clomipramine, which profoundly increases PRL levels and may depress semen quality. Other antidepressants modulating synaptic levels of serotonin, norepinephrine, and/or dopamine may have toxicity similar to SSRIs, but most have not been evaluated. In limited studies, norepinephrine-dopamine reuptake inhibitors (NDRIs) and serotonin agonist/reuptake inhibitors (SARIs) have had minimal effects on PRL levels and on sexual side effects. Antipsychotic medications increase PRL, decrease testosterone, and increase sexual side effects, including ejaculatory dysfunction. The greatest evidence is for chlorpromazine, haloperidol, reserpine, risperidone, and thioridazine, with less effects seen with aripiprazole and clozapine. Remarkably few studies have looked at antipsychotic effects on semen quality, and this is an important knowledge gap in reproductive pharmacology. Lithium increases PRL and LH levels and decreases testosterone although this is informed by few studies. The anticonvulsants, many used for other indications, generally decrease free or bioavailable testosterone with variable effects on the other reproductive hormones. Valproate, carbamazepine, oxcarbazepine, and levetiracetam decrease semen quality; other anticonvulsants have not been investigated for this adverse reaction. Studies are required evaluating endpoints of pregnancy and offspring health for psychotropic medications.

Type A behavior pattern and hyperthymic temperament: possible association with bipolar IV disorder

BACKGROUND

Type A behavior pattern (TABP) has traditionally been reported to be associated with coronary heart disease and, more recently, several researchers have examined its association with depression and bipolar disorder. According to Akiskal and Pinto (1999), there are 2 subtypes of bipolar spectrum which are not associated with manic or hypomanic state. These are bipolar II1/2 (depression in those who have cyclothymic temperament) and bipolar IV (depression in those who have hyperthymic temperament). Our hypothesis is that individuals with hyperthymic temperament may have a tendency towards TABP.

OBJECTIVES

The purposes of the present study are to investigate the association between TABP and hyperthymic temperament and to determine other biological factors associated with TABP.

METHODS

Fifty healthy subjects were assessed for TABP and hyperthymic temperament by self-rating scales, daily activity, sleep time and illuminance by actigraphy, and central serotonergic function via the neuroendocrine challenge test. Serum brain-derived neurotrophic factor (BDNF) levels were also measured.

RESULTS

Stepwise regression analysis indicated that hyperthymic temperament score was positively associated with TABP scores and both sleep time and snooze time were negatively associated with TABP scores. BDNF levels were not associated with TABP scores.

CONCLUSIONS

These findings suggest that individuals with hyperthymic temperament may have a tendency towards TABP, and TABP persons may have short sleep time and short snooze time. Although further studies are required to investigate the association between TABP and affective disorders, the present findings clearly indicate the association between TABP and hyperthymic temperament, which may be associated with bipolar IV disorder. Taking TABP as a risk factor of cardiovascular events into consideration, this association between TABP and bipolar IV disorder may account for the well-known cardiovascular mortality in bipolar disorder.

Biological aspect of hyperthymic temperament: light, sleep, and serotonin

RATIONALE

Hyperthymic temperament is one of several premorbid temperaments putatively associated with bipolar disorder. Several reports suggest that depressive patients with hyperthymic temperament may belong to the proposed soft bipolar spectrum.

OBJECTIVES

To investigate biological aspects of hyperthymic temperament, the present study examined daily activity, sleep time, central serotonergic function, and other relevant variables in relation to hyperthymic temperament in healthy subjects.

METHODS

Fifty six healthy subjects were monitored via the actigraphy system to measure daily total activity, sleep time, and illuminance. A neuroendocrine challenge test was performed to estimate central serotonergic function.

RESULTS

Multiple regression analysis revealed that higher illuminance of daytime, greater fluctuation in sleep time, and lower central serotonergic function significantly and independently predicted hyperthymic temperament scores.

CONCLUSIONS

The present findings suggest that light, sleep, and serotonin are crucial factors in understanding hyperthymic temperament, which may be common to bipolar disorder.

Fluctuating serotonergic function in premenstrual dysphoric disorder and premenstrual syndrome: findings from neuroendocrine challenge tests

RATIONALE

Premenstrual dysphoric disorder (PMDD) has been assumed to be a subtype of premenstrual syndrome (PMS) with depressive symptoms, such as depressive mood, tension, anxiety, and mood liability during luteal phase. At present, no conclusion has been established about serotonergic function in PMDD.

OBJECTIVE

The purpose of this study was to investigate the serotonergic function of PMDD subjects in comparison to PMS without PMDD subjects and normal controls via neuroendocrine challenge tests.

SUBJECTS AND METHODS

Twenty-four women (seven with PMDD, eight with PMS without PMDD, and nine normal controls) were tested on three occasions (follicular phase, early luteal phase, and late luteal phase) receiving paroxetine 20 mg orally as a serotonergic probe at 8:00 A: .M: . Plasma ACTH and cortisol were measured prior to the administration and every hour for 6 h thereafter.

RESULTS

As a whole, there were significant differences in serotonergic function measured by ACTH and cortisol responses to paroxetine challenge across these three groups. PMDD subjects showed higher serotonergic function in follicular phase but lower serotonergic function in luteal phase, compared with women with PMS without PMDD and normal controls.

CONCLUSION

The present findings suggest that PMDD women have fluctuating serotonergic function across their menstrual cycles and that the pattern may be different from PMS without PMDD.

Perospirone in the treatment of patients with delirium

Perospirone is a recently developed atypical antipsychotic with potent serotonin 5-HT2 and dopamine D2 antagonist activity. Other atypical antipsychotics including risperidone, quetiapine and olanzapine have been widely used for treatment, not only for schizophrenia symptoms but also for delirium, because of their low potential to induce extrapyramidal disturbances. In the present study the effectiveness and safety of perospirone in patients with delirium are described. Thirty-eight patients with DSM-IV delirium were given open-label perospirone. To evaluate the usefulness of perospirone, scores from 13 severity items of the Delirium Rating Scale-Revised-98 were assessed. Data were gathered from October 2003 to September 2004. Perospirone was effective in 86.8% (33/38) of patients, and the effect appeared within several days (5.1 +/- 4.9 days). The initial dose was 6.5 +/- 3.7 mg/day and maximum dose of perospirone was 10.0 +/- 5.3 mg/day. There were no serious adverse effects. However, increased fatigue (15.2%), sleepiness (6.1%), akathisia (3.0%) and a decline in blood pressure (3.0%) were observed. It is proposed that perospirone may be another safe and effective atypical antipsychotic drug for the treatment of delirium symptoms in hospitalized patients. This is a preliminary open trial, and further randomized double-blind placebo-controlled tests are needed.

The effect of perospirone on auditory P300 in schizophrenia: a preliminary study

The present study was performed to determine the effect of perospirone, a novel antipsychotic drug with D(2)/5-HT(2A) antagonist and partial 5-HT(1A) agonist properties, on auditory P300 in eight patients with chronic schizophrenia. Switching to an equivalent dose of perospirone from prior antipsychotic medication was associated with a significant improvement in the negative symptoms of the positive and negative syndrome scale (PANSS). The change in P300 amplitude following a switch to perospirone correlated significantly with the improvement of general psychopathology symptoms, as well as with the change in scores on items of delusions, hallucinatory behavior, emotional withdrawal, depression, poor attention, and disturbance of volition. These results suggest that clinical improvement in response to perospirone in some patients may, at least in part, be mediated through cognitive change indexed by P300 in chronic schizophrenia.

Role of 5-HT(1A) receptors in the modulation of stress-induced lactate metabolism in the medial prefrontal cortex and basolateral amygdala

RATIONALE

Lactate has been shown to play a significant role in energy metabolism and reflect neural activity in the brain.

OBJECTIVES

Using in vivo microdialysis technique, we measured extracellular lactate concentrations in the medial prefrontal cortex (mPFC) and the basolateral amygdaloid (BLA) nucleus of rats under electric foot shock stress. Moreover, to examine the role of serotonin (5-HT)(1A) receptors in brain energy metabolism in response to stressors, we attempted to determine whether the stress-induced changes of extracellular lactate levels in the mPFC and BLA are attenuated by tandospirone, a partial agonist at 5-HT(1A) receptors, or perospirone, a novel atypical antipsychotic with a 5-HT(1A) receptor partial agonist and 5-HT(2A)/dopamine-D(2) antagonist property.

RESULTS

Foot shock stress led to an increase in extracellular lactate concentrations both in the mPFC and BLA. Tandospirone (2 mg/kg) attenuated the foot shock stress-induced increase of extracellular lactate concentrations in both of the brain regions, which was blocked by pretreatment with WAY-100635, a selective 5-HT(1A) antagonist. On the other hand, perospirone (0.3 mg/kg) attenuated the increment of extracellular lactate concentrations in the mPFC and BLA, which was unaltered by pretreatment with WAY-100635.

CONCLUSIONS

These results indicate that the foot shock stress-induced increase in lactate metabolism is partly regulated by 5-HT(1A) receptors both in cortical and limbic regions.

Perospirone in the treatment of schizophrenia: effect on verbal memory organization

The present study was performed to determine if perospirone, a novel antipsychotic drug with D2/5-HT2A antagonist and partial 5-HT1A agonist properties, would improve memory organization in twelve patients with chronic schizophrenia. Switching to equivalent dose of perospirone from prior antipsychotic medication was associated with a significant improvement in indices of verbal memory organization of the Auditory Verbal Learning Test. Negative symptoms and extrapyramidal side effects were also ameliorated after switching to perospirone. The distinct cognitive enhancement profile of perospirone may be attributable to its partial 5-HT1A agonist action.