Insulin may be key to fighting Alzheimer's disease - Times Online: "Insulin, the hormone that regulates levels of sugar in the blood, may slow or prevent memory loss caused by Alzheimer’s disease, a study suggests.
Researchers examining the effects of diabetes drugs on the brain have found that the medication appears to protect cells responsible for the formation of memory.
The work offers further support for the theory that Alzheimer’s could be caused by a form of diabetes linked to the body’s failure to produce and process insulin effectively.
Cells in the hippocampus are susceptible to damage caused by amyloid beta-derived diffusible ligands (ADDLs), toxic proteins that build up in people with Alzheimer’s.
ADDLs attack the synapses – the junctions between nerve cells through which impulses pass – which help form memory. After the proteins have attached, the synapses lose their capacity to respond to incoming information, resulting in memory loss.
The researchers discovered that damage to neurons exposed to ADDLs was blocked by insulin, which stopped the proteins from attaching to the cells. The insulin-sensitising drug rosiglitazone enhanced protection afforded by low levels of insulin, the study showed.
William Klein, a professor of neurobiology and physiology at the Weinberg College of Arts and Sciences and a researcher in Northwestern University’s Cognitive Neurology and Alzheimer’s Disease Centre, said: “Therapeutics designed to increase insulin sensitivity in the brain could provide new avenues for treating Alzheimer’s disease.
“Sensitivity to insulin can decline with ageing, which presents a novel risk factor for Alzheimer’s disease. Our results demonstrate that bolstering insulin signalling can protect neurons from harm.”
Sergio Ferreira, another member of the research team and a professor of biochemistry in Rio de Janeiro, added: “Recognising that Alzheimer’s disease is a type of brain diabetes points the way to novel discoveries that may finally result in disease-modifying treatments for this devastating disease.” "