Apocynin prevents vascular effects caused by chronic exposure to low concentrations of mercury.

UNLABELLED: Mercury increases the risk of cardiovascular disease and oxidative stress and alters vascular reactivity. This metal elicits endothelial dysfunction causing decreased NO bioavailability via increased oxidative stress and contractile prostanoid production. NADPH oxidase is the major source of reactive oxygen species (ROS) in the vasculature. Our aim was to investigate whether treatment with apocynin, an NADPH oxidase inhibitor, prevents the vascular effects caused by chronic intoxication with low concentrations of mercury. Three-month-old male Wistar rats were treated for 30 days with a) intramuscular injections (i.m.) of saline; b) HgCl(2) (i.m. 1(st) dose: 4.6 µg/kg, subsequent doses: 0.07 µg/kg/day); c) Apocynin (1.5 mM in drinking water plus saline i.m.); and d) Apocynin plus HgCl(2). The mercury treatment resulted in 1) an increased aortic vasoconstrictor response to phenylephrine and reduced endothelium-dependent responses to acetylcholine; 2) the increased involvement of ROS and vasoconstrictor prostanoids in response to phenylephrine, whereas the endothelial NO modulation of such responses was reduced; and 3) the reduced activity of aortic superoxide dismutase (SOD) and glutathione peroxidase (GPx) and increased plasma malondialdehyde (MDA) levels. Treatment with apocynin partially prevented the increased phenylephrine responses and reduced the endothelial dysfunction elicited by mercury treatment. In addition, apocynin treatment increased the NO modulation of vasoconstrictor responses and aortic SOD activity and reduced plasma MDA levels without affecting the increased participation of vasoconstrictor prostanoids observed in aortic segments from mercury-treated rats. CONCLUSIONS: Mercury increases the vasoconstrictor response to phenylephrine by reducing NO bioavailability and increasing the involvement of ROS and constrictor prostanoids. Apocynin protects the vessel from the deleterious effects caused by NADPH oxidase, but not from those caused by prostanoids, thus demonstrating a two-way action.

[Changes in factors associated with the nutrition transition in Mexico]. / Cambios en factores relacionados con la transición alimentaria y nutricional en México.

OBJECTIVES: To describe the demographic and socioeconomic changes, food availability and food expense in Mexico during 1980-2000. METHODS: From official statistics (Population Census, FAO Food Balance Sheets, Family Income and Expense National Survey and Economic Census) we estimated the evolution of population distribution according to locality size, occupational structure, woman participation in the wage-earning labor force, minimum wage, availability of food establishments and expense in food. RESULTS: The percentage of the population that lives in urban areas has increased, they are employed in the tertiary sector, womens participation in the labor market has increased but real minimum wages have decreased. Vegetables, oleaginous, oils, fish and seafood availability have decreased whereas animal fat, vegetables, fruits, softdrinks, meats and egg availability have increased. The number of inexpensive restaurants (cocinas económicas and fondas) has also increased. Food expenses have decreased while amount of money spent in food consumed away from home has increased. CONCLUSIONS: In Mexico, the growth in urban areas and the tertiary job sector shows a parallel growth in the availability of high fat and protein food, a greater diet variety and more opportunities to consume food not prepared in the home. On the other hand, the sale of equipment and places designed for recreational physical activity have increased. By reducing employment in the primary sector it is foreseeable that labor intensive physical activity will become less important overtime.

Cambios en factores relacionados con la transición alimentaria y nutricional en México / Changes in factors associated with the nutrition transition in Mexico

Objetivo: Describir las características demográficas y socioeconómicas al igual que sus cambios, así como la disponibilidad de alimentos y el gasto en alimentación en México, durante el periodo 1980-2000. Material y métodos: A partir de estadísticas oficiales (Censos de Población, hojas de balance de la FAO, Encuesta Nacional de Ingresos y Gastos de los Hogares y Censos Económicos) se estimó la evolución de distribución de la población de acuerdo al tamaño de localidad, estructura ocupacional, participación de la mujer en el trabajo asalariado, salario mínimo, disponibilidad de alimentos per cápita, disponibilidad de establecimientos en los que se expenden alimentos y gasto destinado para alimentación. Resultados: Los cambios socioeconómicos que se observaron fueron: aumento del porcentaje de población que habita en zonas urbanas, de la población ocupada en el sector terciario, de la participación de la mujer en el trabajo asalariado, así como la disminución del valor real del salario mínimo. Disminuyó la disponibilidad de leguminosas, oleaginosas, aceites vegetales, pescados y mariscos, mientras que se incrementó la de grasas animales, verduras, frutas, bebidas alcohólicas, carnes y huevo. Aumentó el número de restaurantes, fondas y cocinas económicas. El gasto destinado para alimentación ha disminuido, no así el de bebidas y alimentos consumidos fuera del hogar. Conclusiones: En México, el aumento de las zonas urbanas y del trabajo en el sector terciario es paralelo al aumento en la disponibilidad de alimentos ricos en grasa y proteína, de una mayor variedad de la dieta y más oportunidades para consumir alimentos preparados fuera del hogar. Por la reducción de los empleos en el sector primario es previsible que la actividad física laboral cada vez tenga menos importancia. Por el contrario, se ha incrementado la venta de equipos y establecimientos relacionados con la actividad física recreativa.

OBJECTIVES: To describe the demographic and socioeconomic changes, food availability and food expense in Mexico during 1980-2000. METHODS: From official statistics (Population Census, FAO Food Balance Sheets, Family Income and Expense National Survey and Economic Census) we estimated the evolution of population distribution according to locality size, occupational structure, woman participation in the wage-earning labor force, minimum wage, availability of food establishments and expense in food. RESULTS: The percentage of the population that lives in urban areas has increased, they are employed in the tertiary sector, womens participation in the labor market has increased but real minimum wages have decreased. Vegetables, oleaginous, oils, fish and seafood availability have decreased whereas animal fat, vegetables, fruits, softdrinks, meats and egg availability have increased. The number of inexpensive restaurants (cocinas económicas and fondas) has also increased. Food expenses have decreased while amount of money spent in food consumed away from home has increased. CONCLUSIONS: In Mexico, the growth in urban areas and the tertiary job sector shows a parallel growth in the availability of high fat and protein food, a greater diet variety and more opportunities to consume food not prepared in the home. On the other hand, the sale of equipment and places designed for recreational physical activity have increased. By reducing employment in the primary sector it is foreseeable that labor intensive physical activity will become less important overtime.