Scientists at the University of California , San Francisco ( UCSF ) have managed to correct some of the memory and learning offspring associated withDown syndrome . Their survey involved mice that had been genetically engineered to develop a mouse equivalent of Down syndrome , rather than citizenry , but the researchers say their finding are still promising .
Down syndromeis a stipulation because of an extra chromosome . Most people have 23 pair of chromosome , which carry genetic material , but mass with Down syndrome have three copies of chromosome 21 , rather than a pair . The superfluous chromosome results from an error in cadre division and can come from either the mother ’s testis or Padre ’s spermatozoon .
Down syndrome can run tophysical changeslike hapless muscle timbre as well as cognitive and behavioral issue like delayed speech development and a unforesightful care span . It can also increase the risk of other health condition like visual sense problem and gist abnormalities . Nevertheless , thanks to melioration in care and support for hoi polloi with Down syndrome , many with the experimental condition live long , happy lives .
Scientists have traditionally focused on the genetic science of the experimental condition , but the team behind the new study decide to wait at protein production instead . They analyze protein production in mice mastermind to develop most of the chromosomal , developmental , and cognitive freakishness that move human race with Down syndrome using a process called polysome profiling .
Publishing their finding inScience , the team base that the engineered shiner live a 39 pct fall in protein production in the genus Hippocampus of their brains , a region fundamental to memory board formation . They concluded that this is the answer of the activation of a circuit anticipate the integrated tension response ( ISR ) by cells in the hippocampus .
The squad also found that the ISR was activated in brain samples take from deceased people who had Down syndrome . They even spot the pattern in the cells of a someone with Down syndrome who only carried an surplus chromosome in sure cells . The ISR was only activated in the redundant - chromosome cells .
“ The cell is forever monitoring its own health , ” explained Professor Peter Walter of UCSF in astatement . “ When something go wrong , the cell responds by making less protein , which is usually a level-headed response to cellular stress . But you need protein synthetic thinking for higher cognitive functions , so when protein synthesis is reduced , you get a pathology ofmemory formation . ”
To see if they could undo this declination in protein production , the researchers blocked an enzyme in the mice known as PKR , which triggers activating of the IRS . Without this enzyme , the ISR was not activated and protein production did not falter , which in routine improved the mice ’s cognitive abilities .
Interestingly , three different approaches successfully meliorate cognition and even boosted physical brain role . These were deleting the PKR gene totally , yield the mouse a drug that quells activity of the PKR enzyme , and using a drug that heighten protein production to counter the effects of the ISR .
It ’s significant to remember that the inquiry is in its infancy and is ground on findings in black eye and post - mortem human tissue . Further enquiry will be needed to affirm the results and find out more about the link between Down syndrome and the ISR .
Nevertheless , the researchers go for that their findings might contribute to the development of potential treatment for Down syndrome in the time to come .
In aperspective pieceaccompanying the study , Mark Halliday and Giovanna Mallucci of the University of Cambridge write that the team “ provide compelling evidence that Down syndrome ( DS ) , the most common genetic cause of intellectual disability , join the pantheon of neurological disorders in which dysregulated ISR signal play a key persona . ”
energizing of the IRS has also been linked toAlzheimer ’s , traumatic brain injury , andprion disease , the study authors mention .
