A 6-month prospective, observational, naturalistic, uncontrolled study to evaluate the effectiveness and tolerability of oral ziprasidone in patients with schizophrenia.

This multicenter, uncontrolled, naturalistic study evaluated the effectiveness and tolerability of 6 months of treatment with ziprasidone in 1266 patients with a diagnosis of schizophrenia. The percentage of responders (at least 30% reduction in PANSS total score) in the primary analysis sample (n=1022) was 47.3% (95% CI 44.2-50.4) at the end of the study. Patients showed a significant and clinically relevant reduction in the PANSS total, positive, negative and general psychopathology subscales scores (effect size of 1.60, 1.83, 0.62 and 1.40 respectively). Overall, 453 (35.8%) patients withdrew from the study; 9.3% withdrew owing to adverse events. Ziprasidone doses greater than 120 mg/day were associated with a lower risk of discontinuation for any cause (OR 0.46, 95% CI 0.33-0.65) Ziprasidone was well tolerated. Most common side effects were: insomnia, somnolence and nervousness. The effectiveness and tolerability of ziprasidone in clinical practice are consistent to those previously shown in the more restricted and homogeneous populations of clinical trials.

Serotonin upregulates the activity of phagocytosis through 5-HT1A receptors.

1 In this study, we investigated whether serotonin could regulate the in vitro activity of phagocytosis through 5-hydroxytryptamine or serotonin (5-HT(1A)) receptors. 2 Mouse peritoneal macrophages were cultured with serotonin and the activity of phagocytosis was assessed by the uptake of zymosan and latex particles added to the culture media. Specific binding of [(3)H]8-OH-DPAT and immunohistochemistry using an affinity-purified anti-5-HT(1A)-receptor antibody were assayed in the macrophages. In addition, we took advantage of the availability of pharmacological inhibitors of nuclear factor-kappaB (NF-kappaB) to explore its role in the regulation of the 5-HT(1A) receptor. 3 Serotonin increased the in vitro activity of phagocytosis in a dose-dependent manner. The 5-HT(1A) receptor agonist (+/-)-8-hydroxy-2-(di-n-propyl-amino)-tetralin (R(+)-8-OH-DPAT) reproduced these effects. Serotonin- or R(+)-8-OH-DPAT-induced increases in phagocytosis were blocked by the 5-HT(1A) receptor antagonist WAY100635 and the NF-kappaB inhibitor pyrrolidinedithiocarbamate. Moreover, mouse peritoneal macrophages expressed specific binding sites for [(3)H]8-OH-DPAT when cultivated in the presence of zymosan or latex beads. Immunohistochemistry confirmed the expression of the 5-HT(1A) receptor protein in the macrophages. 4 These results show that serotonin can upregulate the activity of peritoneal macrophages through 5-HT(1A) receptors.

Cold exposure inhibits leptin secretion in vitro by a direct and non-specific action on adipose tissue.

OBJECTIVE: Leptin secretion is reduced by low temperatures in experimental animals, and this effect has been explained as an adaptive mechanism to cold environments. This study investigated the in vitro effects of cold exposure on human white adipose tissue. DESIGN: To understand whether the low temperature action is a direct or a mediated effect, leptin secretion was assessed in vitro in human omental adipose tissue incubated at varied temperatures, from 38 donors. As an internal control, the effect of reduced temperatures on in vitro GH secretion by GH3 cells was assessed. METHODS: Measurement of hormones secretion was carried out with an RIA, while human ob gene mRNA expression was assessed with reverse transcription PCR. RESULTS: Compared with the standard temperature of 37 degrees C, leptin secretion by human adipose tissue was significantly (P<0.05) reduced when the incubations were carried out at 34.5 degrees C (41% inhibition), and 32 degrees C (68% inhibition), with no parallel changes in the ob mRNA expression. At these reduced temperatures, glucocorticoid-mediated leptin secretion was well preserved. When the effect of reduced temperatures was assessed on in vitro GH secretion, a superimposable reduction was observed. CONCLUSIONS: These results indicate: (i) that low temperatures reduce leptin secretion by acting directly on the adipose tissue and (ii) that the similar reduction in a hormone unrelated to energy metabolism, such as GH, suggests that the observed reduction is a mechanical perturbation of leptin secretion, which may be devoid of physiological implications.