RESUMEN
BACKGROUND: Agomelatine is an antidepressant drug that acts as an agonist of melatoninergic MT1/2 receptors and an antagonist of serotonergic 5-HT2C receptors. Studies suggest that agomelatine has anxiolytic properties in social anxiety, but there are no studies that assessed the effects of this compound in human experimental anxiety induced by a public speaking test. The objective of our investigation was to assess the effects of agomelatine on human experimental anxiety using the Simulation Public Speaking Test (SPST). METHODS: Agomelatine (25 mg, n = 14), citalopram (20 mg, n = 14), venlafaxine (75 mg, n = 14), or placebo (n = 14) were administered in single doses to healthy volunteers in a double-blind study. Subjective anxiety was assessed with the Visual Analogue Mood Scale. Arterial blood pressure, heart rate, and blood levels of prolactin and cortisol were also recorded, as well as plasma levels of the 3 drugs. RESULTS: The SPST induced significant subjective, physiological, and hormonal effects in all groups. The SPST also increased the anxiety and decreased mental sedation Visual Analogue Mood Scale factors during the anticipatory and performance phases of the test. Citalopram increased anxiety during the test in females, whereas agomelatine and venlafaxine were not different from placebo. CONCLUSIONS: Confirming previous results, a serotonin selective reuptake inhibitor, citalopram, caused an anxiogenic effect in the SPST only in females. Acute administration of a low dose of agomelatine failed to modify the behavioral and physiological changes caused by this test. Future studies using higher doses and repeated administration should investigate if agomelatine behavioral and physiological effects could be detected in human experimental anxiety models.
RESUMEN
The aim of this study is to assess the effects of sibutramine (S) 15 mg/day, fluoxetine (F) 60 mg/day, and metformin (M) 1,700 mg/day, as an adjunct therapy to a 1,500 kcal/day diet, in reducing anthropometric and metabolic parameters. S (n= 8), F (n= 9), and M (n= 8) were compared to placebo (n= 10) in 35 obese patients in a 90-day trial. Side effects were also studied during the treatment. The data demonstrated that F therapy resulted in a greater average reduction in BMI (11.0 percent), weight (10.0 percent), abdominal circumference (11.0 percent) and percentfatty-tissue (12.8). An elevation in HDL-cholesterol (25.8 percent) and a reduction in average triglyceride levels (28.3 percent) were also shown. S presented a 7.91 percent reduction in the abdominal circumference and a 9.65 reduction in percentfatty-tissue was also found. M group presented reductions in BMI (4.03 percent), waist circumference (6.92 percent), HOMA (23.5 percent) and blood pressure (6.08 percent in systolic and 2.08 percent in diastolic). In general, the three drugs can be considered well tolerated. We concluded that F and S demonstrated a greater mean reduction in anthropometric and metabolic parameters when compared to M, however all of them are useful for that purpose, when the subjectsÆ characteristics are considered.
O objetivo deste estudo foi avaliar o efeito da sibutramina (S) 15 mg/dia, fluoxetina (F) 60 mg/dia, e metformina (M) 1.700 mg/dia, associadas a uma dieta de 1.500 kcal/dia, na redução de parâmetros antropométricos e metabólicos. S (n= 8), F (n= 9) e M (n= 8) foram comparadas ao placebo (n= 10) em 35 pacientes obesos durante 90 dias de tratamento. As reações adversas também foram avaliadas durante o tratamento. O grupo F demonstrou uma redução no IMC (11,0 por cento), peso (10,0 por cento), circunferência abdominal (11,0 por cento) e por cento de tecido adiposo (12,8). Também foram observados um aumento nos níveis de HDL-colesterol (25,8 por cento) e uma redução nos níveis de triglicérides (28,3 por cento), no grupo F. O grupo S apresentou uma redução de 7,91 por cento na circunferência abdominal e de 9,65 na por cento de tecido adiposo. Já o grupo M apresentou reduções no IMC (4,03 por cento), circunferência abdominal (6,92 por cento), HOMA (23,5 por cento) e pressão arterial (6,08 por cento na sistólica, 2,08 por cento na diastólica). Os três fármacos analisados foram bem tolerados durante o tratamento. Concluímos que a F e a S demonstraram maior eficácia na redução dos parâmetros antropométricos e metabólicos dos pacientes obesos quando comparadas à M, entretanto todas podem ser prescritas para essa finalidade, desde que sejam consideradas as características individuais dos pacientes.