Comer en tiempos de "crisis": nuevos contextos alimentarios y de salud en España / Eating in a time of "crisis": New health and dietary contexts in Spain

En las sociedades industrializadas se está reflexionando cada vez más sobre el impacto de la inseguridad alimentaria, entendida como la dificultad para asegurar la accesibilidad de una parte de la población a los recursos alimentarios suficientes para garantizar su subsistencia y bienestar. Con base en datos recogidos a partir de una investigación en curso en España, este artículo discute, por un lado, si la actual crisis económica está revirtiendo algunas de las tendencias positivas que el sistema agroalimentario industrial había favorecido, como la disminución de las diferencias sociales en el consumo y el derecho a la alimentación. Por otro lado, reflexiona acerca de la creciente precarización en las estrategias alimentarias y en el estado de salud de la población, así como sobre la necesidad de considerar la desigualdad social como variable explicativa de las diversas maneras de alimentarse.

This article analyzes the reasons why food insecurity in Spain must increasingly be understood as lack of access to sufficient food resources to guarantee the survival and wellbeing of part of the population. Using data collected in an ongoing research project, two possible causes for this are explored. First, it is argued that certain positive developments that seemed firmly established, such as recognition of the right to an adequate diet and the leveling out of social differences in food consumption, are now being reversed by the current economic crisis. Second, the analysis focuses on strategies people in precarious circumstances use to obtain food, their relationship to health, and the need to take social inequality into consideration as an explanatory variable in accounting for different ways of procuring daily sustenance.

Streptozotocin-induced diabetes mellitus affects lysosomal enzymes in rat liver

It has been previously shown that dextran sulfate administered to diabetic rats accumulates in the liver and kidney, and this could be due to a malfunction of the lysosomal digestive pathway. The aim of the present study was to evaluate the expression and activities of lysosomal enzymes that act upon proteins and sulfated polysaccharides in the livers of diabetic rats. Diabetes mellitus was induced by streptozotocin in 26 male Wistar rats (12 weeks old), while 26 age-matched controls received only vehicle. The livers were removed on either the 10th or the 30th day of the disease, weighed, and used to evaluate the activity, expression, and localization of lysosomal enzymes. A 50-60% decrease in the specific activities of cysteine proteases, especially cathepsin B, was observed in streptozotocin-induced diabetes mellitus. Expression (mRNA) of cathepsins B and L was also decreased on the 10th, but not on the 30th day. Sulfatase decreased 30% on the 30th day, while glycosidases did not vary (or presented a transitory and slight decrease). There were no apparent changes in liver morphology, and immunohistochemistry revealed the presence of cathepsin B in hepatocyte granules. The decrease in sulfatase could be responsible for the dextran sulfate build-up in the diabetic liver, since the action of sulfatase precedes glycosidases in the digestive pathway of sulfated polysaccharides. Our findings suggest that the decreased activities of cathepsins resulted from decreased expression of their genes, and not from general lysosomal failure, because the levels of glycosidases were normal in the diabetic liver.

Cathepsin B is activated as an executive protease in fetal rat alveolar type II cells exposed to hyperoxia

Alveolar type II cells are main target of hyperoxia-induced lung injury. The authors investigated whether lysosomal protease, cathepsin B (CB), is activated in fetal alveolar type II cells in the transitional period from the canalicular to saccular stages during 65%-hyperoxia and whether CB is related to fetal alveolar type II cell (FATIIC) death secondary to hyperoxia. FATIICs were isolated from embryonic day 19 rats and exposed to 65%-oxygen for 24 h and 36 h. The cells exposed to room air were used as controls. Cell cytotoxicity was assessed by lactate dehydrogenase-release and flow cytometry, and apoptosis was analyzed by TUNEL assay and flow cytometry. CB activity was assessed by colorimetric assay, qRT-PCR and western blots. 65%-hyperoxia induced FATIIC death via necrosis and apoptosis. Interestingly, caspase-3 activities were not enhanced in FATIICs during 65%-hyperoxia, whereas CB activities were greatly increased during 65%-hyperoxia in a time-dependent manner, and similar findings were observed with qRT-PCR and western blots. In addition, the preincubation of CB inhibitor prior to 65%-hyperoxia reduced FATIIC death significantly. Our studies suggest that CB activation secondary to hyperoxia might have a relevant role in executing the cell death program in FATIICs during the acute stage of 65%-hyperoxia.

Expression of cathepsin-B and -D in rat's brain after traumatic brain injury / 法医学杂志

OBJECTIVE@#To study the expression of cathepsin-B and -D in different time point after traumatic brain injury.@*METHODS@#Traumatic brain injury (TBI) model was established on rats, cathepsin-B and cathepsin-D immunofluorescence staining and confocal microscope analysis were performed. Positive cells were counted by confocal microscope and image analysis techniques were used to determine the morphological changes in each group.@*RESULTS@#Immunofluorescence staining results showed that cathepsin-B was activated 1 hour after TBI while cathepsin-D was not activated until 12hour after TBI. Both of them got to their peak during 4 to 8days, and kept a high level of activating 32days after TBI. Cathepsin-B and -D positive cells did not merge with caspase-3 positive cells until 6 h after TBI.@*CONCLUSION@#Cathepsin-B and -D could be the diagnostic markers of TBI and can estimating time course of lateral TBI. They blocked caspase-3 activation at the beginning period after TBI and started to promote cell death with caspase-3 6 h after TBI.