INFEKTIO MM. PSYYKKISTEN SAIRAUKSIEN AIHEUTTAJINA

[Bb]

Lähettäjä: Soijuv Lähetetty: 25.10.2005 10:40

Erilaiset fyysiset ja psyykkiset sairaudet saattavat olla kokonaan tai osittain infektion laukaiseman autoimmuuniprosessin aikaansaamia. Tästä ovat esimerkkeinä esim. 1 tyypin diabetes, MS-tauti, bulimia, anoreksia jne:


Molecular self-loathing

Sep 29th 2005
From The Economist
Anorexia and bulimia may be autoimmune diseases and so may several other psychiatric illnesses

SOMETIMES, the immune system works in mysterious ways. During an infection one of its roles is to produce antibodies designed to attack and eliminate the invading bugs. However, in certain unlucky individuals the body also develops so-called autoantibodies which attack its own tissue, sometimes with devastating effects. The result is known as an autoimmune disease, two well-known examples of which are type-1 diabetes and multiple sclerosis. But there is a widespread suspicion among researchers in the field that a lot more diseases than these have an autoimmune component. In particular, they think, a number of illnesses usually labelled as psychiatric are actually, at bottom, the result of autoimmunity.

Until now, that suspicion has been based on correlations between certain sorts of infection and certain sets of psychiatric symptoms. But work just published in the Proceedings of the National Academy of Sciences by Serguei Fetissov of the Karolinska Institute in Stockholm and his colleagues has tied the connection more tightly for two psychiatric eating disorders anorexia nervosa and bulimia nervosa.

Dr Fetissov's work suggests that abnormal levels of autoantibodies against hormones called melanocortins are a crucial part of the cause of these two diseases. Melanocortins are small protein molecules that carry messages between nerve cells in the brain. They are involved in regulating a variety of complex behaviours, including social interactions, stress responses and most importantly in this context food intake. So it is easy to see how interfering with them could cause anorexia and bulimia.
Shooting the messenger

To test this idea, Dr Fetissov and his colleagues analysed blood serum from three groups of women (both anorexia and bulimia are more common in women than in men). One of these groups consisted of people diagnosed as anorexic. The second was composed of individuals diagnosed as bulimic. The third contained people with no eating disorder.

The researchers looked to see whether there was any relationship between the levels of autoantibodies to melanocortins in these women and their expression of particular psychological traitsâ??such as â??Drive for thinness