Effects of Marijuana and Diazepam on Lipid Peroxidation, Na+, K+ ATPase, and Levels of Glutathione and 5-HTP in Rat Brain

Our aim was to evaluate the effects of marijuana (Mar) and diazepam (Dz) on lipid peroxidation (TBARS), Na+, K+ ATPase activity, levels of glutathione (GSH) and 5-hydroxytryptophan (5-HTP). Male Wistar rats were given a single dose per group: extract of Mar (100 µL/kg), Dz (5 mg/kg), Mar plus Dz, and NaCl for control. Sixty mins after treatment, animals were sacrificed, and their brains extracted and homogenised to measure GSH, TBARS and 5-HTP levels. Na+, K+ ATPase and total ATPase activities. GSH and TBARS did not show differences respect to controls. Na+, K+ ATPase activity was similar as well. However, groups treated with Mar, total ATPase activity decreased significantly (p < 0.05). Levels of 5-HTP decreased significantly (p = 0.0001) in rats treated either with Mar and or Dz. Mar and Dz induced biochemical effects on the serotonergic metabolism, which can alter the development and function in rat brain, because it has also been involved in scavenging free radicals present there

Neuroprogression: the hidden mechanism of depression

Norma A Labra Ruiz,1 Daniel Santamar&iacute;a del &Aacute;ngel,1 Hugo Ju&aacute;rez Olgu&iacute;n,2 Miroslava Lindoro Silva2 1Laboratory of Neurosciences, Instituto Nacional de Pediatria (INP), Mexico City, Mexico; 2Laboratory of Pharmacology, Instituto Nacional de Pediatr&iacute;a (INP), and Faculty of Medicine, Universidad Nacional Aut&oacute;noma de Mexico, Mexico City, Mexico Abstract: For many years, depressive disorder (DD) was considered a transient and natural disease of people&acute;s mood. Its etiology had been attributed mainly to biochemical alterations of the monoamines and their receptors. Nevertheless, its prevalence and considerable impact on the family and social environment of those afflicted by it have placed the disease as a global public health problem. Neuroprogression is the term used to describe the changes in several psychiatric conditions evidenced and observed in the clinical manifestations, biochemical markers, and cerebral structures of the patients with major depressive disorder (MDD), which frequently overlap with neurodegenerative disorders. DD is considered a potentially aggressive state of neuronal deterioration involving apoptosis, reduced neurogenesis, decreased neuronal plasticity, and increased immune response. Clinically, it encompasses a poor response to treatment and an increase in depressive episodes, both of which bring about vulnerability and decline of functions associated with structural changes in the brain. The interest of this work is to review the metabolic processes involved in the morphologic alterations in the limbic system reported in patients with MDD, as well as the neurologic bases of this complex pathology that include environmental stress, genetic vulnerability, alterations in the neurotransmission, and changes in the neuroplasticity, all of which today bring into limelight a mechanism of progressive neuronal damage. Keywords: depressive disorder, monoamines, neuroprogression, neuroendocrin

Farmacocinética comparada de metformina, en forma sólida y en formulación extemporánea líquida para pediatría, en voluntarios adultos sanos

ANTECEDENTES: fraccionar o pulverizar tabletas de metformina para ajustar dosis pediátricas dificulta su administración, genera inestabilidad del fármaco (oxidación/fotosensibilidad) y relativiza su biodisponibilidad. Se propone como alternativa de ajuste de dosis y de uniformidad de contenido una formulación extemporánea líquida a partir de tabletas de marca comercial. OBJETIVO: determinar la biodisponibilidad de metformina en formulación líquida, en voluntarios adultos sanos, para demostrar que su comportamiento farmacocinético permanece inalterado. MATERIALES Y MÉTODOS: estudio clínico, aleatorio, cruzado y longitudinal, en adultos sanos voluntarios (n=12), 7 varones y 5 mujeres, de 24.3 ± 1.8 años, con índice de masa corporal = 24.9 ± 2.5 kg/m2. Se obtuvieron muestras sanguíneas en gotas, colectadas en tarjetas Whatman 903®, a las 0.25, 0.5, 1, 2, 4, 8 y 12 horas de ingerir 250 mg del fármaco. Se extrajo el fármaco a partir de 5 discos de papel filtro con sangre impregnada (16 μL), por precipitación directa, con acetonitrilo (ACN) y metanol.  La detección fue en una columna AcQuity UPLC BEH HILIC (2.1 × 100mm, 1.7 μm) por espectrometría de masas en tándem. Fase móvil: acetato de amonio 5 mM y ACN (80:20; v/v), a 0.25 mL/min isocráticamente. La farmacocinética se determinó mediante el programa Win Nonlin Pro 3.1 y las diferencias se evaluaron por ANOVA de una vía (p ≤ 0.05). RESULTADOS: el método fue exacto, preciso, selectivo y lineal entre 50 y 1000 ng/mL, coeficiente de determinación (r) de 0.9982. Las muestras extraídas y almacenadas a 4°C fueron estables por 17 horas y hasta 2 meses a -80°C. La metformina en tableta tuvo una Cmáx de 553.4 ng/mL y de 692.2 ng/mL con la formulación líquida. El Tmáx fue menor con la solución edulcorada (1.6 h) que con la tableta (1.8 h). La ke fue menor con la forma líquida (0.29 vs. 0.32 h-1), lo que sugiere que se eliminó más rápidamente. El AUC0-12 fue igual en ambas formas (F=0.002, Fcrit=6.3). CONCLUSIONES: la formulación líquida de metformina es igualmente biodisponible que la forma farmacéutica original, con la ventaja de permitir dosis menores que la tableta, ajuste preciso de dosis y uniformidad de contenido