In studies conducted earlier, laboratory levels showed that being infected in early age will have some effects due to the hard immune response that the body present at sequential illness, which has other negative side effects that hurt the patient’s learning and memory, as it was discovered from recent researches that having problems in learning is usually due to the immunity system.
Scientists found that this is a result of the signaling molecule called Interleukin-1, or IL-1that specialized immune system cells is produced in the brain called microglia release in case of infection in the body.
While the IL-1 is so important to have normal learning and memory in the hippocampus region of the brain, but in case that IL-1 is release too much in the brain it can damage and affect the learning and memory.
In an experiment conducted on young rates for almost ten years, these rats were infected in purpose and after this they were also infected again with consisting of only harmless, dead bacteria, when they were tested after the second infection they showed highly effective immune response, and there learning and memory was highly affected.
The doctor who did this study said that “The microglia remember that infection
and respond differently, The infection itself wasn’t doing permanent damage. It was changing the immune system somehow.” The second infection according to results didn’t have to involve the brain directly, in addition the harm of the bacteria on the limps made signals that urged the glia in the brain pump out extra IL-1, and according to another researcher the rats who were infected did handle it very well but on the cost of hurting their brain.
After this test, scientists tried to find out what is the change that happened to the rats by using immunology techniques to take a specific cell from the brain tissue fast enough to know what had happened to it, the result was that they saw the galial cells behaving the same as immune system macrophages behave in other places in the body(gobbling up other cells and tearing them apart) they also did a pruning function in order to streamline the brain’s neural architecture as it grows up.
Also to experience the effects the happened to the memory, the team did another test in which they exposed the rats to some voice and mild shocks in their feet, when repeating the test regular rats remembered what happened by freezing in their places while other rats produced IL-1, and it was like it’s the first time to experience the effects, it was like Alzheimer symptoms, said one of the researchers, according to this we can know why some people are more weak to cognitive impairments from chronic infections, aging and neurodegenerative diseases such as Alzheimer’s disease