It seems that scientists are on the verge of revolutionizing how doctors diagnose and treat early stage Alzheimer’s. Earlier this year, a group of researchers reported a detectable urine odor biomarker
in a mouse model of the disease. Now, researchers from Tel Aviv University and Harvard University have found a correlation
between a blood-borne biomarker protein and declining cognitive conditions. The discovery could propel a new diagnostic blood test to detect the early signs of Alzheimer’s disease.
Currently, diagnosis of Alzheimer’s disease is very limited and time-consuming. Doctors and experts have to conduct a battery of cognitive tests to look for impairments in cognition, memory, social functioning, and behaviors. The tests are highly subjective, but remain the best practice for diagnosing Alzheimer’s, as the true confirmation can only come from brain autopsy reports.
But researchers now propose that a blood-based protein could be the new biomarker for detecting Alzheimer’s.
The protein is known as activity-dependent neuroprotective protein (ADNP)
, and is essential for brain formation. Mutations in this gene are frequently associated with autism spectrum disorder. Moreover, ADNP is the only protein that has been shown to decrease significantly in the serum of Alzheimer’s patients.
In the current study, researchers from Tel Aviv University and Harvard University sought to uncover a pattern of ADNP levels in 11 healthy elderly individuals, 15 mild cognitively impaired (MCI) patients, and 17 Alzheimer’s dementia patients. They found that higher ADNP protein levels in the blood serum are significantly associated with higher “premorbid intelligence,” which is defined as a person’s cognitive function prior to the onset of brain disease. Conversely, lower ADNP mRNA levels are associated with higher amyloid presence in cognitively normal elderly individuals.
To put it another way, “The more ADNP RNA found in the blood cells, the fewer aggregates found in the brain of elderly cognitively normal individuals,” said Illana Gozes, study leader and professor at the Tel Aviv University in Israel. “We have found a clear connection between ADNP levels in the blood and amyloid plaques — a hallmark Alzheimer’s — in the brain.”
They also reported that ADNP levels correlate with intelligence quotient (IQ) levels. Gozes says, “…the more ADNP in the serum, the higher the person’s IQ level.”
The consequences of these findings could potentially improve how doctors assess intelligence decline in pre-Alzheimer’s and Alzheimer’s patients. The authors propose that instead of the laborious subjective cognitive tests that are currently in practice, doctors could use regular blood tests to measure ADNP levels, which can disclose Alzheimer’s risks and related IQ status.
“This study has provided the basis to detect this biomarker in routine, non-invasive blood tests, and it is known that early intervention is invaluable to Alzheimer’s patients,” said Prof. Gozes. “We are now planning to take these preliminary findings forward into clinical trials — to create a pre-Alzheimer’s test that will help to tailor potential preventative treatments.”
Additional source: EurekAlert!