RESUMEN
Visfatin is a multi-functional molecule that can act intracellularly and extracellularly as an adipokine, cytokine and enzyme. One of the main questions concerning visfatin is the mechanism of its secretion; whether, how and from which cells visfatin is released. The objective of this in vitro study was to observe the active secretion of visfatin from 3T3-L1 preadipocytes and adipocytes, HepG2 hepatocytes, U-937, THP-1 and HL-60 monocytes and macrophages. The amount of visfatin in media and cell lysate was always related to the intracellular enzyme, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), to exclude the passive release of visfatin. Visfatin was not found in media of 3T3-L1 preadipocytes. In media of 3T3-L1 adipocytes and HepG2 hepatocytes, the ratio of visfatin to the amount of GAPDH was identical to cell lysates. Hence, it is likely that these cells do not actively secrete visfatin in a significant manner. However, we found that significant producers of visfatin are differentiated macrophages and that the amount of secreted visfatin depends on used cell line and it is affected by the mode of differentiation. Results show that 3T3-L1 adipocytes and HepG2 hepatocytes released visfatin only passively during the cell death. U-937 macrophages secrete visfatin in the greatest level from all of the tested cell lines.
Asunto(s)
Adipocitos/metabolismo , Hepatocitos/metabolismo , Macrófagos/metabolismo , Nicotinamida Fosforribosiltransferasa/metabolismo , Células 3T3-L1 , Animales , Células Hep G2 , Humanos , Ratones , Células U937RESUMEN
This article focuses on rationing of expensive medical care in the Czech Republic. It distinguishes between political and clinical decision levels and reviews the debate in the Western literature on explicit and implicit rules. The contemporary situation of the Czech health care system is considered from this perspective. Rationing reoccurred in the mid 90s after the shift in health care financing from fee-for-service to prospective budgets. The lack of explicit rules is obvious. Implicit forms of rationing, done by physicians at the clinical level prevail, implying uncontrolled power of the medical profession and lacking transparency for ethical considerations of equity to access. It seems to be acceptable for physicians to play the role of allocators, probably because of their experience with rationing during the socialist period. Traditional rationing stereotypes from the previous regime seem to persist despite the health care system transformation during the 90s.
Asunto(s)
Ética Médica , Asignación de Recursos para la Atención de Salud , Reforma de la Atención de Salud/economía , Reforma de la Atención de Salud/normas , Médicos/ética , República Checa , Asignación de Recursos para la Atención de Salud/economía , Política de Salud , Humanos , Rol del Médico , PolíticaRESUMEN
Male Wistar rats were offered food for either 24, 6, or 1 h a day at two different ambient temperatures -21 or 6 degrees C. At room temperature, rats offered food for 6 h a day matched their food intake to that of rats with 24 h of food-availability in 2-3 days, so that no main changes in total food intake, gross food efficiency, and body weight were recorded. No impairment of thermoregulatory capacity was recorded as judged by the unaltered oxidative capacity of brown adipose tissue and skeletal muscle. Nonetheless, a transient hypothermia was recorded at the beginning of the experiment in the food-restricted group. Rats that were only offered food 1 h a day were unable to sustain the food intake of the control animals, so that a continuous decline in body weight and a negative gross food efficiency ensured. In the cold, the food intake of rats offered food for only 6 or 1 h a day was similar to that showed by the corresponding groups at 21 degrees C. These results suggest a maximum rate for digestive processes, irrespective of ambient temperature. However, such levels of food intake were clearly insufficient to cope with the thermoregulatory enhanced energy demand at 6 degrees C, ad judged by the decrease in body weight.
Asunto(s)
Temperatura Corporal/fisiología , Peso Corporal/fisiología , Ingestión de Alimentos/fisiología , Animales , Privación de Alimentos , Masculino , Ratas , Ratas WistarRESUMEN
After 8 weeks of intermittent fasting, mice fed both a standard laboratory diet and a high-fat diet became hyperphagic and showed an increased amount of glycogen storage in the liver. An important effect of the adaptation to intermittent feeding with a high-fat diet seems to be an activation of the oxidation of lipids. Lipid oxidation prevails over lipogenesis so that the protein levels in the liver and skeletal muscle are preserved and maintained constant.
Asunto(s)
Grasas de la Dieta/farmacología , Glucógeno/metabolismo , Metabolismo de los Lípidos , Hígado/metabolismo , Músculo Esquelético/metabolismo , Proteínas/metabolismo , Animales , Composición Corporal/efectos de los fármacos , Composición Corporal/fisiología , Ayuno , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Músculo Esquelético/efectos de los fármacos , Tamaño de los Órganos/efectos de los fármacosRESUMEN
The simultaneous effect of intermittent starvation and a high-fat diet were investigated in mice after several weeks of experimental feeding. The animals adapted to intermittent fasting fed a high-fat diet showed a lower degree of hyperphagia than animals adapted to intermittent fasting fed a standard laboratory diet. The weight of both individual portions of the stomach was elevated in adapted animals fed both a standard laboratory diet and the high-fat diet. The weight of the small intestine was increased in adapted animals fed a high-fat diet. The length of the small intestine was not changed after 8 weeks of intermittent starvation in both adapted groups (standard laboratory diet, high-fat diet). A higher amount of body fat was found in both groups of animals adapted to intermittent fasting (standard laboratory diet, high-fat diet) but adapted animals fed a high-fat diet showed less body fat than adapted animals fed a standard laboratory diet. Lower levels of serum lipids were found in adapted animals fed a high-fat diet. These results suggest that both lipogenesis and lipid oxidation are accentuated by intermittent starvation and a high-fat diet act concomitantly.