Lower total serum protein, albumin, and beta- and gamma-globulin in major and treatment-resistant depression: effects of antidepressant treatments.

Strong evidence has recently been reported that major depression is accompanied by an acute phase response (APR), characterized by elevated levels of positive acute phase proteins (APPs) and decreased levels of negative APPs. The APR is also reflected in lowered total serum protein (TSP) and specific changes in the major electrophoretically separated protein fractions. The present study examined pretreatment and posttreatment serum TSP and the concentrations and percentages of the major electrophoretically separated serum protein fractions in 37 major depressed subjects, of whom 29 had treatment-resistant depression (TRD), and in 29 normal controls. We found that TSP and the percentage and concentration of serum albumin (Alb) and gamma-globulin fraction were significantly lower in major depression and TRD than in normal controls. Serum beta-globulin concentrations were significantly lower in major depressed and TRD subjects than in normal controls. The percentages of the alpha 1- and alpha 2-globulin fractions were significantly higher in major depressed subjects than in normal controls. There were no significant effects of subchronic treatment with antidepressants on TSP, the percentage or concentration of the major electrophoretically separated protein fractions, i.e. alpha 1-, alpha 2- and beta-globulin. There was a significant increase in percentage of the gamma-globulin fraction after subchronic treatment with antidepressants. The results support the hypothesis that major depression and TRD are accompanied by a chronic APR.