Neuroscience

Articles and news from the latest research reports.

Posts tagged gene activation

38 notes

Mild Blast Injury Causes Molecular Changes in Brain Akin to Alzheimer’s Disease

A multicenter study led by scientists at the University of Pittsburgh School of Medicine shows that mild traumatic brain injury after blast exposure produces inflammation, oxidative stress and gene activation patterns akin to disorders of memory processing such as Alzheimer’s disease. Their findings were recently reported in the online version of the Journal of Neurotrauma.

Blast-induced traumatic brain injury (TBI) has become an important issue in combat casualty care, said senior investigator Patrick Kochanek, M.D., professor and vice chair of critical care medicine and director of the Safar Center for Resuscitation Research at Pitt. In many cases of mild TBI, MRI scans and other conventional imaging technology do not show overt damage to the brain.

“Our research reveals that despite the lack of a lot of obvious neuronal death, there is a lot of molecular madness going on in the brain after a blast exposure,” Dr. Kochanek said. “Even subtle injuries resulted in significant alterations of brain chemistry.”

The research team developed a rat model to examine whether mild blast exposure in a device called a shock tube caused any changes in the brain even if there was no indication of direct cell death, such as bleeding. Brain tissues of rats exposed to blast and to a sham procedure were tested two and 24 hours after the injury.

Gene activity patterns, which shifted over time, resembled patterns seen in neurodegenerative diseases, particularly Alzheimer’s, Dr. Kochanek noted. Markers of inflammation and oxidative stress, which reflects disruptions of cell signaling, were elevated, but there was no indication of energy failure that would be seen with poor tissue oxygenation.

“It appears that although the neurons don’t die after a mild injury, they do sustain damage,” he said. “It remains to be seen what multiple exposures, meaning repeat concussions, do to the brain over the long term.”

(Source: upmc.com)

Filed under TBI brain injury inflammation brain tissue gene activation concussions neuroscience science

70 notes

Rhythmic Changes in Gene Activation Power the Circadian Clock
Rhythms underlie the daily functions of mammals, from sleep-wake cycles to metabolic processes in the liver. The circadian clock has evolved in response to daily changes in temperature and light in the environment. At the root of circadian rhythms are daily fluctuations in gene expression, which occur in part through the process of transcription—the creation of RNA from sequences of DNA. Although past studies have uncovered how changes in transcription states relate to irreversible processes, for example when cells become more specialized, much less is known about how transcription fluctuates in synch with recurring cycles.
Read more

Rhythmic Changes in Gene Activation Power the Circadian Clock

Rhythms underlie the daily functions of mammals, from sleep-wake cycles to metabolic processes in the liver. The circadian clock has evolved in response to daily changes in temperature and light in the environment. At the root of circadian rhythms are daily fluctuations in gene expression, which occur in part through the process of transcription—the creation of RNA from sequences of DNA. Although past studies have uncovered how changes in transcription states relate to irreversible processes, for example when cells become more specialized, much less is known about how transcription fluctuates in synch with recurring cycles.

Read more

Filed under circadian clock circadian rhythms gene activation mRNA science

free counters