Acrolein Induces Endoplasmic Reticulum Stress and Causes Airspace Enlargement

BACKGROUND: Given the relative abundance and toxic potential of acrolein in inhaled cigarette smoke, it is surprising how little is known about the pulmonary and systemic effects of acrolein. Here we test the hypothesis whether systemic administration of acrolein could cause endoplasmic reticulum (ER) stress, and lung cell apoptosis, leading to the enlargement of the alveolar air spaces in rats. METHODS: Acute and chronic effects of intraperitoneally administered acrolein were tested. Mean alveolar airspace area was measured by using light microscopy and imaging system software. TUNEL staining and immunohistochemistry (IHC) for active caspase 3 and Western blot analysis for active caspase 3, and caspase 12 were performed to detect apoptosis. The ER-stress related gene expression in the lungs was determined by Quantitative real-time PCR analysis. Acrolein-protein adducts in the lung tissue were detected by IHC. RESULTS: Acute administration of acrolein caused a significant elevation of activated caspase 3, upregulation of VEGF expression and induced ER stress proteins in the lung tissue. The chronic administration of acrolein in rats led to emphysematous lung tissue remodeling. TUNEL staining and IHC for cleaved caspase 3 showed a large number of apoptotic septal cells in the acrolein-treated rat lungs. Chronic acrolein administration cause the endoplasmic reticulum stress response manifested by significant upregulation of ATF4, CHOP and GADd34 expression. In smokers with COPD there was a considerable accumulation of acrolein-protein adducts in the inflammatory, airway and vascular cells. CONCLUSIONS: Systemic administration of acrolein causes endoplasmic reticulum stress response, lung cell apoptosis, and chronic administration leads to the enlargement of the alveolar air spaces and emphysema in rats. The substantial accumulation of acrolein-protein adducts in the lungs of COPD patients suggest a role of acrolein in the pathogenesis of emphysema

Sleep disorders in high school and pre-university students

Adolescence is a period in which youngsters have to make choices such as applying for university. The selection process is competitive, and it brings distress and anxiety, risk factors for the appearance of sleep disorders. OBJECTIVE: To verify the occurrence of sleep disorders in third-year high school and pre-university students. METHOD: This cross-sectional descriptive study comprised a sample of 529 students (M=241, F=288) from three public schools, four private schools and two pre-university courses - a middle-class neighborhood in the city of São Paulo - aged between 16 and 19 years old. We used the Pittsburgh Sleep Quality Index (PSQI) - a standardized questionnaire. RESULTS: The participants (52.9%) took about 30 minutes to fall asleep, with an average of 306.4 minutes asleep, moderate daytime sleepiness (n=243, 45.9%) and indisposition (n=402, 75.9%) to develop the activities. The scores (M and F) were similar regarding problems that affect sleep. CONCLUSION: The investigated population showed sleep disorders and poor sleep quality