4 replies to this topic

[johnross47]

http://www.scienceda...40929093856.htm

 

How the brain ages is still largely an open question -- in part because this organ is mostly insulated from direct contact with other systems in the body, including the blood and immune systems. In research that was recently published in Science, Weizmann Institute researchers Prof. Michal Schwartz of the Neurobiology Department and Dr. Ido Amit of Immunology Department found evidence of a unique "signature" that may be the "missing link" between cognitive decline and aging. The scientists believe that this discovery may lead, in the future, to treatments that can slow or reverse cognitive decline in older people.

 

Until a decade ago, scientific dogma held that the blood-brain barrier prevents the blood-borne immune cells from attacking and destroying brain tissue. Yet in a long series of studies, Schwartz's group had shown that the immune system actually plays an important role both in healing the brain after injury and in maintaining the brain's normal functioning. They have found that this brain-immune interaction occurs across a barrier that is actually a unique interface within the brain's territory.This interface, known as the choroid plexus, is found in each of the brain's four ventricles, and it separates the blood from the cerebrospinal fluid. Schwartz: "The choroid plexus acts as a 'remote control' for the immune system to affect brain activity. Biochemical 'danger' signals released from the brain are sensed through this interface; in turn, blood-borne immune cells assist by communicating with the choroid plexus.This cross-talk is important for preserving cognitive abilities and promoting the generation of new brain cells."

This finding led Schwartz and her group to suggest that cognitive decline over the years may be connected not only to one's "chronological age" but also to one's "immunological age," that is, changes in immune function over time might contribute to changes in brain function -- not necessarily in step with the count of one's years.

 

To test this theory, Schwartz and research students Kuti Baruch and Aleksandra Deczkowska teamed up with Amit and his research group in the Immunology Department. The researchers used next-generation sequencing technology to map changes in gene expression in 11 different organs, including the choroid plexus, in both young and aged mice, to identify and compare pathways involved in the aging process.

That is how they identified a strikingly unique "signature of aging" that exists solely in the choroid plexus -- not in the other organs. They discovered that one of the main elements of this signature was interferon beta -- a protein that the body normally produces to fight viral infection. This protein appears to have a negative effect on the brain: When the researchers injected an antibody that blocks interferon beta activity into the cerebrospinal fluid of the older mice, their cognitive abilities were restored, as was their ability to form new brain cells. The scientists were also able to identify this unique signature in elderly human brains. The scientists hope that this finding may, in the future, help prevent or reverse cognitive decline in old age, by finding ways to rejuvenate the "immunological age" of the brain.

 

 

 

 

 

[Danail Bulgaria]

Very interesting find. Well done

[to age or not to age]

Johnross

One thing that makes this interesting to me is that again and again, a pathway which is designed to help us when

we are young turns against us; operating at a level that keeps us fit for procreation, but runs on unchecked or at a level

that harms us from middle age on.  The mtor pathway is another example, which is why rapamycin, given to 60 year old mice, extends their lifespan. My guess is that science should look for the "black hats" in many things that are good for us when we are young.  There in will lie the answers, the targets.  

[mpe]

60 year old mice, wow, I have missed something.

[Mind]

Saw this yesterday: http://www.kurzweila...n-immune-system

 

Apparently there is a connection between the brain and immune system, perhaps overturning decades of theory regarding how various neurological diseases develop and are treated.

 

 

Overrturning decades of textbook teaching, researchers at the University of Virginia School of Medicine have discovered that the brain is directly connected to the immune system by vessels previously thought not to exist.

The finding could have significant implications for the study and treatment of neurological diseases ranging from autism to Alzheimer’s disease to multiple sclerosis.

“It changes entirely the way we perceive the neuro-immune interaction. We always perceived it before as something esoteric that can’t be studied. But now we can ask mechanistic questions.” said Jonathan Kipnis, PhD, professor in the UVA Department of Neuroscience and director of UVA’s Center for Brain Immunology and Glia (BIG).