Immune Changes in Schizophrenia

The concept that a dysfunctional immune system plays a role in the etiology of schizophrenia can be traced back to the 19th century when it was estimated that approximately one-third of psychotic patients in Europe were suffering from neurosyphilis, a condition that has largely disappeared following the introduction of antibiotics in the 20th century. However, in the last century, it was observed that viral infections such as rubella and the influenza virus were also associated with the symptoms of schizophrenia, at least in some patients [6]. Perhaps the most compelling evidence for a link between schizophrenia and a dysfunctional immune system has been provided by Lindholm et al. [7] who demonstrated that a locus at chromosome 6p22 was linked to both schizophrenia and to the genes of the human lymphocyte (HLA) system. This system is crucially involved in combating viruses which might account for the increased vulnerability of schizophrenic patients to viral infections.

Another interesting connection between schizophrenia and the immune system has been provided by the susceptibility of first-degree relatives of schizophrenic patients to insulin-dependent diabetes mellitus. This susceptibility appears to be associated with the HLA locus on chromosome 6 [8]. Such an observation is particularly important because of the association between the metabolic syndrome and type 2 diabetes in schizophrenic patients being treated with the second-generation antipsychotic olanzapine. Clearly, there are differences in the genetic signal between type 1 and type 2 diabetes. Thus, there appears to be a decrease in the frequency of schizophrenia in patients with type 1 diabetes [9], which suggests that insulin, as such, is not directly linked to the pathology of schizophrenia. As is becoming apparent, type 2 diabetes is a possible consequence of dysfunctional metabolism initiated by immune, endocrine and mitochondrial changes that are symptomatic of schizophrenia.

Nutrient excess

Nutrient excess

> Energy input << energy output

Inflammation

> Energy input << energy output

(long-chain fatty acid accumulation; fat depots)

Obesity

Inflammation

Insulin resistance

Metabolic disorders (cardiovascular disease; type 2 diabetes, etc.)

Fig. 1. Link between inflammation, obesity, diabetes and cardiovascular disease in schizophrenic patients.

Despite the circumstantial evidence linking viral infections to schizophrenia, no single virus has so far been identified as a causal agent. Furthermore, there is no evidence of a major immune reaction in the brains of schizophrenic patients; for example, no marked gliosis or evidence of lymphocyte infiltrates even though there is evidence of diffuse humoral reactivity in some patients. In addition, there is evidence that some of the peripheral immune changes are reflected in the brain [10, 11]. Leonard [10] has critically reviewed the evidence linking a disorder of the immune system to the psychopathology of schizophrenia

Supplements For Diabetics

Supplements For Diabetics

All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.

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