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A hipertensão arterial é a principal causa de morte precoce no mundo. Existem diversos fatores que contribuem para sua variação dentro da fisiologia do ritmo circadiano, e que exercem forte impacto sobre o controle da pressão arterial (PA). Os valores da PA sofrem interferência de acordo com o horário da medida. Nas primeiras horas da manhã PAS aumenta rapidamente em 20 a 25 mmHg e a PAD em 10 a 15 mmHg. As drogas anti-hipertensivas, sofrem diversas influências na sua absorção, metabolização e excreção dependentes do ritmo circadiano e de suas propriedades físico-químicas. O ciclo circadiano exerce grande impacto no controle da PA, e apenas modificando o horário das prescrições, seguindo o ritmo circadiano, talvez seja possível obter melhor controle pressórico com menor dose da medicação, reduzindo assim, as possíveis reações adversas

Hypertension is the leading cause of early death worldwide. Several factors contribute to its variation within the physiology of circadian rhythm, and these factors have a strong impact on blood pressure (BP) control. BP values are influenced by the measurement time. In the early hours of the morning, SBP increases rapidly by 20 to 25 mmHg and DBP by 10 to 15 mmHg. Antihypertensive drugs suffer from a variety of influences on their absorption, metabolism and excretion, depending on the circadian rhythm and its physical-chemical properties. The circadian cycle has a great impact on BP control, and only by changing the schedule of prescriptions, following the circadian rhythm, it may be possible to obtain better pressure control with a lower dose of medication, thus reducing potential adverse reactions

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Sibutramine is a non-selective serotonin-norepinephrine reuptake inhibitor orally administered for weight loss. In a previous study, we showed pharmacological mechanisms involved in the reduction of sperm quality and fertility of rats exposed for 30 days to this anorexigen in the light phase of the light-dark (l/d) cycle. It is already known that rodents are nightlife animals, with higher metabolic activity during the dark phase than in the light phase of the light-dark (l/d) cycle. Thus, the present study aimed to investigate whether the deleterious effects on reproductive parameters after sibutramine administration would be enhanced after a shorter period of exposure during the dark phase of the l/d cycle. For this, adult male Wistar rats were treated with sibutramine (10 mg/kg/d) or vehicle for 15 days during the dark phase of the l/d cycle. Sibutramine treatment decreased final body and reproductive organ weights, as well as serum testosterone levels. Sperm transit time through the epididymis was accelerated, and sperm concentration and motility were diminished in the sibutramine-exposed rats. The decrease in sperm concentration was also verified in the epididymal histological sections. In conclusion, the deleterious effects of sibutramine on reproductive parameters of male rats were enhanced when the exposure occurred in the dark phase of the l/d cycle, even after a short exposure duration. Our results reinforce the impact of timing on drug therapeutic action.

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The last decade has witnessed the emergence of new chronopharmacological perspectives. In the case of sleep disorders, the accumulating evidence suggests that even a minor dysfunction in the biological clock can impact broadly upon body physiology causing increases in sleep onset latency, phase delays or advances in sleep initiation, frequent nocturnal awakenings, reduced sleep efficiency, delayed and shortened rapid eye movement sleep and increased periodic leg movements, among others. Thus, restoration of the adequate circadian pattern of proper sleep hygiene, targeted exposure to light and the use of chronobiotic drugs, such as melatonin, which affect the output phase of clock-controlled circadian rhythms, can help to recover the sleep-wake cycle. The optimization of drug effects and/or minimization of toxicity by timing medications with regard to biological rhythms is known as chronotherapeutics. While chronotherapeutical approaches have been particularly successful in the treatment of hypertension, allergies and some forms of cancer, a time-dependent pharmacological approach can be also effective when dealing with sleep disruptions like insomnia. A large proportion of patients under benzodiazepine (BZD)/Z drug treatment fail to achieve a complete and sustained recovery and are left with residual symptoms, like tolerance or dependency, that make relapse or recurrence more likely, and poorer quality of life a reality. Thus the chronic and extensive use of BZD/Z drugs has become a public health issue and has led to multiple campaigns to reduce both prescription and consumption of BZD/Z-drugs. This short review discusses available data on the efficacy of melatonin to reduce chronic BZD use in insomnia patients.

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The objective of this research work was to design, develop and optimize the self micro-emulsifying drug delivery system (SMEDDS) of Felodipine (FL) filled in hard gelatine capsule coated with polymer in order to achieve rapid drug release after a desired time lag in the management of hypertension. Microemulsion is composed of a FL, Lauroglycol FCC, Transcutol P and Cremophor EL. The optimum surfactant to co-surfactant ratio was found to be 2:1. The resultant microemulsions have a particle size in the range of 65-85 nm and zeta potential value of -13.71 mV. FL release was adequately adjusted by using pH independent polymer i.e. ethyl cellulose along with dibutyl phthalate as plasticizer. Influence of formulation variables like viscosity of polymer, type of plasticizer and percent coating weight gain was investigated to characterize the time lag. The developed formulation of FL SMEDDS capsules coated with ethyl cellulose showed time lag of 5-7 h which is desirable for chronotherapeutic application.

O objetivo desse trabalho de pesquisa foi planejar, desenvolver e otimizar sistema de liberação de fármaco auto-microemulsificante(SMEDDS) de felodipino (FL) em cápsulas de gelatina dura revestidas com polímero, a fim de obter liberação rápida após tempo desejado no manejo da hipertensão. A microemulsão é composta de FL, lauroglilcol FCC, Transcutol P e Cremophor EL. A proporção ótima de tensoativo e de co-tensoativo foi de 2:1. As microemulsões resultantes têm tamanho de partícula na faixa de 65-85 nm com potencial zeta de -13,71 mV. A liberação de FL foi ajustada adequadamente, utilizando-se polímero independente de pH, como etilcelulose com ftalato de dibutila como plastificante. A influência das variáveis da formulação, como viscosidade do polímero, tipo de plastificante e ganho percentual de peso do revestimento foi investigada para caracterizar o intervalo de tempo de liberação. A formulação de cápsulas de FL SMEDDS revestidas com etilcelulose mostrou intervalo de tempo de liberação de 5 a 7 horas, o que é desejável para uma aplicação cronoterapêutica.

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Se ha demostrado que las funciones fisiológicas oscilan durante ciclos de 24 horas (circadianos), menos de 24 horas (ultradianos) y mayores de 24 horas (infradianos), lo que se denomina ritmos biológicos (cronobiología). El presente artículo hace énfasis en cómo los ritmos biológicos pueden incidir en la respuesta a los medicamentos y la terapéutica psiquiátrica (cronofarmacología, cronoterapia). Esta variable de estudio podría ofrecer nuevos márgenes en la eficacia y seguridad de los medicamentos y hacer su uso más racional.

It has been shown that physiological functions oscillate during cycles of 24 hours (circadian), of less than 24 (ultradian) and larger than 24 hours (infradian). These are called biological rhythms (chronobiology). This article emphasizes on how biological rhythms may influence response to drugs and psychiatric treatment (chronopharmacology, chronotherapy). The study of this variable could offer new perspectives on efficacy and safety of drugs in order to pursue a more rational use of them.

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Se ha demostrado que las funciones fisiológicas oscilan durante ciclos de 24 horas (circadianos), menos de 24 horas (ultradianos) y mayores de 24 horas (infradianos), lo que se denomina ritmos biológicos (cronobiología). El presente artículo hace énfasis en cómo los ritmos biológicos pueden incidir en la respuesta a los medicamentos y la terapéutica psiquiátrica (cronofarmacología, cronoterapia). Esta variable de estudio podría ofrecer nuevos márgenes en la eficacia y seguridad de los medicamentos y hacer su uso más racional.

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The objective of this study was to prepare and evaluate chronotherapeutic drug delivery systems (ChrDDs) of torsemide. Compression coated tablets (CCT) containing torsemide in the core tablet were prepared by the compression coating technique with different grades of polyethylene oxide (PEO WSR 301 & 1105). The optimized formulations were characterised for tabletting parameters and drug polymer interaction by Fourier-Transform Infrared Spectroscopy (FTIR).The hardness of all the CCT using PEO WSR 301 & PEO WSR 1105 were in the range 6-8 kg/cm² & 5.5 to 7 kg/cm² respectively. Their friability values were <0.3 percent. All the CCT showed a clear lag time but finalized as per the predetermined lag time. As the amount of PEO was increased in the outer layer the drug released was delayed. The drug content of all the CCT was >99 percent. The FTIR studies showed no interaction throughout the process of development. Formulations of F7 and of P7 were considered optimized formulations since they yielded a predetermined lag time of 6h before burst release. Hence, these formulations can be exploited to achieve chronotherapeutic drug delivery systems of Torsemide for the treatment of hypertension at the time the patient needs it.

O objetivo deste estudo foi preparar e avaliar sistemas cronoterapêuticos de liberação de fármacos (ChrDDs) de torsemida. Comprimidos revestidos por compressão (CCT) contendo torsemida no (núcleo) foram preparados pela técnica de revestimento por compressão, com diferentes categorias de óxido de polietileno (PEO WSR 301 & 1105). As formulações otimizadas foram caracterizadas por parâmetros de compressão e interação fármaco polímero por Infravermelho com Transformada de Fourier (FTIR). A dureza dos CCT utilizando PEO WSR 301 e PEO WSR 1105 foi entre 6-8 kg/cm² e 5,5 a 7 kg/cm², respectivamente. Os valores de friabilidade foram <0,3 por cento. Todos os CCT mostraram claro tempo de retardo, mas finalizaram de acordo com o tempo de retardo pré-determinado. À medida que a quantidade de PEO aumentava na camada mais externa, a liberação do fármaco era retardada. O teor de fármaco em todos os CCT foi >99 por cento. Os estudos de FTIR mostraram que não h[a interação durante o processo de desenvolvimento. As formulações F7 e P7 foram consideradas otimizadas, uma vez que resultaram em tempo de retardo pré-determinado de 6 h antes da liberação por meio de explosão. Dessa forma, estas formulações podem ser exploradas para se obter sistemas de liberação.

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Recently we have evaluated the role of glucocorticoids (GC) and other stress hormones in the pathogeny of age-related diseases. In order to perform this evaluation, we considered the DOHaD paradigm discussing long-term effects of adverse perinatal factors. In the present work, a part of the data collected previously was used for analyzing the role of GC in aging, as well as in age-related pharmacotherapy. The data were gathered in various databases, preferably in English, during the last 25-30 years. Although some authors suggest that GC can be considered as hormones of aging, the majority of investigators are quite careful in this respect. Nevertheless, it appears that the role of GC in various stages of ontogeny and transitions between them is well established. Besides, there are a lot of data that confirm a contribution of GC to the phenomena of perinatal programming/imprinting of adult diseases. What for the relationship between GC and aging, some studies confirm its existence, at least partially. Having analyzed the dynamics of morbidity and mortality of age-related diseases, we concluded on the absence of evidence in favor of unique general scheme of aging, where GC could play a role. However, in a rather paradoxal mode it was demonstrated that GC participate, at least indirectly, in the mechanisms of action of various drugs used for the treatment of cardiometabolic disorders (beta-blockers, angiotensin antagonists, some oral hypoglycemic agents) and neuropsychiatric diseases (antidepressants, antipsychotic agents, benzodiazepines and some anticonvulsive medicines), as well as in the effects of toxic agents (for example, drugs of abuse, including caffeine). Using the concept of hormesis, we discuss a reason for frequent utilization of these drugs, and not GC or their antagonists, in age-related pharmacotherapy. The caution is suggested in considering the essential function of GC in aging. Nevertheless, due to existence of theory that connects GC with aging via the mechanisms of allostasis, we are planning to elaborate a more detailed model that might include, besides GC, also some other hormones, cytokines, etc., as well as their interactions. It is stressed that the interactions of GC with other bioregulators should be reevaluated in a chronobiological mode, in order to strengthen the bases of chronopharmacotherapy. One of the principal challenges is the prevention of adverse effects of pharmacotherapy in long-term. In this sense, DOHaD paradigm has opened the discussion of possibility for pharmacotoxicologic programming / imprinting, an important question attracting the attention of researchers.

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