“But what we wanted to know was whether exposure to milder stress, of the kind we experience in our daily lives, can induce tau phosphorylation,” explains senior research associate and first author Dr. Robert A. Rissman.
When the researchers restrained mice for half an hour, it resulted only in a transient phosphorylation of tau. But when they simulated chronic stress by repeating the procedure every day for two weeks, the modification lasted long enough to let tau molecules tumble off the cytoskeleton and pile up in insoluble heaps of protein.
During the study, the researchers genetically engineered mice to lack either CRFR1 or CRFR2.
“And sure enough, the CRF receptors turn out to be integrally and differentially involved,” says Sawchenko.
In the absence of CRFR1, stress-induced tau phosphorylation was abrogated, while in mice missing CRFR2 the effect was amplified, says the researcher, adding that pharmacological studies with small molecule inhibitors replicated the effect.
“We may have discovered another application. Such drugs could have a prophylactic effect or delay the progression of Alzheimer’s disease,” Sawchenko says.
Source-ANI
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