RESUMO
Metabolic modifications during the developmental period can extend longevity. We found that malic enzyme (Men) overexpression during the larval period lengthened the lifespan of Drosophila. Men overexpression by S106-GeneSwitch-Gal4 driver increased pyruvate content and NADPH/NADP(+) ratio but reduced triglyceride, glycogen, and ATP levels in the larvae. ROS levels increased unexpectedly in Men-overexpressing larvae. Interestingly, adults exposed to larval Men-overexpression maintained ROS tolerance with enhanced expression levels of glutathione-S-transferase D2 and thioredoxin-2. Our results suggest that metabolic changes mediated by Men during development might be related to the control of ROS tolerance and the longevity of Drosophila.
Assuntos
Proteínas de Drosophila/biossíntese , Drosophila melanogaster/crescimento & desenvolvimento , Longevidade/fisiologia , Malato Desidrogenase/biossíntese , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster/enzimologia , Drosophila melanogaster/genética , Glutationa Transferase/metabolismo , Glicogênio/metabolismo , Larva/enzimologia , Larva/genética , Larva/crescimento & desenvolvimento , Longevidade/genética , Malato Desidrogenase/genética , NADP/metabolismo , Ácido Pirúvico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxinas/metabolismo , Triglicerídeos/metabolismoRESUMO
OBJECTIVES: In Korea, an average of 258 workers claim compensation for their noise-induced hearing loss (NIHL) on an annual basis. Indeed, hearing disorder ranks first in the number of diagnoses made by occupational medical check-ups. Against this backdrop, this study analyzed the impact of 19 types of noise-generating machines and equipment on the sound pressure levels in workplaces and NIHL occurrence based on a 2009 national survey on work environments. METHODS: Through this analysis, a series of statistical models were built to determine posterior probabilities for each worksite with an aim to present risk ratings for noise levels at work. RESULTS: It was found that air compressors and grinding machines came in first and second, respectively in the number of installed noise-generating machines and equipment. However, there was no direct relationship between workplace noise and NIHL among workers since noise-control equipment and protective gear had been in place. By building a logistic regression model and neural network, statistical models were set to identify the influence of the noise-generating machines and equipment on workplace noise levels and NIHL occurrence. CONCLUSION: This study offered NIHL prevention measures which are fit for the worksites in each risk grade.