Pollution causes brain damage, depression






ISLAMABAD – Long-term exposure to air pollution could damage the brain and cause depression, besides triggering learning and memory problems.
Mice tests showed that, in the long term, dirty air could cause actual physical changes to the brain which resulted in negative effects.
While other studies have looked at the impact of polluted air on heart and lungs, this is one of the first to look at the effect on the brain, said doctoral student Laura Fonken from the Ohio State University who led the study.
“The results suggest that prolonged exposure to polluted air can have visible, negative effects on the brain which can lead to a variety of health problems,” she said, reports the journal Molecular Psychiatry.
“This could have important and troubling implications for people who live and work in polluted urban areas around the world,” Fonken added, according to the a foreign newspaper. Fonken and her colleagues at Ohio State exposed mice to either filtered air or polluted air six hours a day, five days a week for almost half their lifespan which was 10 months.
After 10 months of exposure, behavioural tests were carried out on the rodents, including a learning and memory test.
After five days of training they were placed on a brightly lit area and given two minutes to find the dark escape hole where they would be more comfortable.
The mice which breathed the polluted air took longer to learn where the escape hole was and at later tests they were more likely to forget where it was. In another experiment, mice exposed to the polluted air showed more depressive-like and higher levels of anxiety-like behaviours in one test, but not in another
Nicotine protects brain from Parkinson’s disease
A new research has found that nicotine prevents us from developing Parkinson’s disease by protecting dopamine neurons in the brain. The discovery may lead to entirely new types of treatments for the disease.
“This study raises the hope for a possible neuroprotective treatment of patients at an early step of the disease or even before at a stage where the disease has not been diagnosed according to motor criteria,” said Patrick P. Michel, co-author of the study from the Institut du Cerveau et de la Moelle Epiniere, Hopital de la Salpetriere, in Paris, France.
To make this discovery, scientists used mice genetically engineered without a specific nicotine receptor (the alpha-7 subtype) and mice with a functional receptor.
Using tissue from mouse embryos, researchers prepared brain cultures using conditions that favour the slowly progressing loss of dopamine neurons, a hallmark of the disease.
The scientists found that nicotine had the potential to rescue dopamine neurons in cultures from normal mice, but not in cultures from mice without the nicotine receptor.
These findings suggest that it may be feasible to develop novel therapies for Parkinson’s disease that target nicotine receptors, particularly the alpha-7 nicotine receptor.
Smoking, high BP may shrink your brain
Smoking, high blood pressure, diabetes and being overweight in middle age may cause brain shrinkage and lead to cognitive problems up to a decade later, a new study has suggested.
“These factors appeared to cause the brain to lose volume, to develop lesions secondary to presumed vascular injury, and also appeared to affect its ability to plan and make decisions as quickly as 10 years later. A different pattern of association was observed for each of the factors,” said study author Charles DeCarli, MD, with the University of California at Davis in Sacramento and a Fellow of the American Academy of Neurology.
“Our findings provide evidence that identifying these risk factors early in people of middle age could be useful in screening people for at-risk dementia and encouraging people to make changes to their lifestyle before it’s too late,” added DeCarli.
The study involved 1,352 people without dementia from the Framingham Offspring Study with an average age of 54.
The study found that people with high blood pressure developed white matter hyperintensities, or small areas of vascular brain damage, at a faster rate than those with normal blood pressure readings and had a more rapid worsening of scores on tests of executive function, or planning and decision making, corresponding to five and eight years of chronological aging respectively.
People with diabetes in middle age lost brain volume in the hippocampus (measured indirectly using a surrogate marker) at a faster rate than those without diabetes. Smokers lost brain volume overall and in the hippocampus at a faster rate than nonsmokers and were also more likely to have a rapid increase in white matter hyperintensities.
People who were obese at middle age were more likely to be in the top 25 percent of those with the faster rate of decline in scores on tests of executive function, DeCarli said. People with a high waist-to-hip ratio were more likely to be in the top 25 percent of those with faster decrease in their brain volume.

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