Anti-Inflammatory effects of antidepressants through suppression of the interferon-gamma/interleukin-10 production ratio

There is some evidence that major depression--in particular, treatment-resistant depression (TRD)--is accompanied by activation of the inflammatory response system and that proinflammatory cytokines may play a role in the etiology of depression. This study was carried out to examine the effects of antidepressive agents, i.e., imipramine, venlafaxine, L-5-hydroxytryptophan, and fluoxetine on the production of interferon-gamma (IFN-gamma), a proinflammatory cytokine, and interleukin-10 (IL-10), a negative immunoregulatory cytokine. Diluted whole blood of fluoxetine-treated patients with TRD (mean age, 50.6+/-3.9 years) and age-matched healthy controls (mean age, 51.6+/-1.7 years) and younger healthy volunteers (mean age, 35.4+/-9.6 years) was stimulated with phytohemagglutinin (1 microg/mL) and lipopolysaccharide (5 microg/mL) for 48 hours with and without incubation with the antidepressants at 10-6 M and 10(-5) M. IFN-gamma and IL-10 were quantified by means of enzyme-linked immunoassays. The ratio of IFN-gamma to IL-10 production by immunocytes was computed because this ratio is of critical importance in determining the capacity of immunocytes to activate or inhibit monocytic and T-lymphocytic functions. All four antidepressive drugs significantly increased the production of IL-10. Fluoxetine significantly decreased the production of IFN-gamma. All four antidepressants significantly reduced the IFN-gamma/IL-10 ratio. There were no significant differences in the antidepressant-induced changes in IFN-gamma or IL-10 between younger and older healthy volunteers and TRD patients. Tricyclic antidepressants, selective serotonin reuptake inhibitors, and serotonin-noradrenaline reuptake inhibitors, as well as the immediate precursor of serotonin, have a common, negative immunoregulatory effect by suppressing the IFN-gamma/IL-10 production ratio. It is suggested that the therapeutic efficacy of antidepressants may be related to their negative immunoregulatory effects.

The inflammatory response following delivery is amplified in women who previously suffered from major depression, suggesting that major depression is accompanied by a sensitization of the inflammatory response system

BACKGROUND

There is now evidence that some patients with major depression show an activation of the inflammatory response system (IRS). This study was carried out to examine whether major depression may induce sensitization with increased IRS responses to the stress of child birth.

METHODS

Serum concentrations of interleukin-6 (IL-6), the soluble IL-6 receptor (sIL-6R), sgp130 (the IL-6 signal transducing protein) and the sIL-1R antagonist (sIL-1RA) were determined in 16 and 50 women with and without a lifetime history of major depression, respectively. Blood was collected 3-6 days before delivery and 1 and 3 days after delivery. On each occasion the women completed the Zung Depression Rating Scale (ZDS).

RESULTS

Serum IL-6, sIL-6R, sIL-1RA were significantly higher 1 and 3 days after delivery than before. Women who had suffered from a lifetime history of major depression had greater increases in serum IL-6 and sIL-1RA in the early puerperium than women without a lifetime history. Women who had suffered from a lifetime history of major depression had significantly higher IL-6, and sIL-1RA concentrations 1 and 3 days after delivery than women with a negative life-time history.

CONCLUSIONS

The responses of IL-6 and sIL-1RA following delivery are amplified in women who previously suffered from major depression. The results suggest that major depression is accompanied by a sensitization of the IRS.

Lowered serum dipeptidyl peptidase IV activity is associated with depressive symptoms and cytokine production in cancer patients receiving interleukin-2-based immunotherapy

There is some evidence that treatment with interleukin-2 (IL-2) and interferon-alpha (IFNalpha) frequently induces depressive symptoms and activation of the inflammatory response system (IRS). There is evidence that major depression is accompanied by lowered serum activity of dipeptidyl peptidase IV (DPP IV; EC 3.4.14.5), a membrane-bound serine protease which catalyses the cleavage of some cytokines and neuro-active peptides and which modulates T cell activation and the production of cytokines, such as IL-2. This study was carried out to examine the effects of immunochemotherapy with IL-2 and IFNalpha, alone and together, in cancer patients on serum DPP IV activity in relation to changes in depressive symptoms and the IRS. The Montgomery and Asberg Rating Scale (MADRS), serum DPP IV activity, and the serum IL-6, and IL-2 receptor (IL-2R) concentrations were measured in 26 patients with metastatic cancers before and three and five days after treatment with IL-2 and IFNalpha, alone or together. Treatment with IL-2 with or without IFNalpha significantly suppressed serum DPP IV activity. The MADRS scores were significantly elevated by treatment with IL-2 with or without IFNalpha, but not IFNalpha alone. The immunochemotherapy-induced decreases in serum DPP IV were significantly and inversely correlated with the increases in the MADRS. Treatment with IL-2 alone or combined with IFNalpha also elevated serum IL-6 and IL-2R. There were significant and inverse correlations between the immuchemotherapy-induced decreases in serum DPP IV and the elevations in serum IL-6 or IL-2R. In conclusion, treatment with IL-2/IFNalpha decreases serum DPP IV activity within 3-5 days and the immunochemotherapy-induced decreases in serum DPP IV activity are significantly and inversely related to treatment-induced increases in severity of depression and signs of activation of the IRS.

Improvement of Clostridium tumour targeting vectors evaluated in rat rhabdomyosarcomas

Previous studies have demonstrated the feasibility of using apathogenic clostridia as a promising strategy for hypoxia-specific tumour targeting. The present study shows that the use of the vascular targeting compound combretastatin A-4 phosphate could significantly (P<0.001) increase the number of Clostridium vegetative cells in rat rhabdomyosarcomas with sizes between 0.2 cm(2) and 3 cm(2). Furthermore, this study showed that administration of metronidazole for a 9-day period was sufficient to eliminate systemically administered Clostridium from the tumour. Moreover, previous Clostridium spore administration did not effect tumour colonisation, regardless of the immune response status of the host.

Lower serum activity of prolyl endopeptidase in anorexia and bulimia nervosa

The aim of this study was to examine whether anorexia and bulimia nervosa are accompanied by lower serum activity of prolyl endopeptidase (PEP;EC 3.4.21.26; post-proline cleaving enzyme), a cytosolic endopeptidase which cleaves peptide bonds on the carboxyl side of proline in proteins of relatively small molecular mass. Substrates of PEP are, amongst others, neuroactive peptides, such as arginine vasopressin, luteinizing hormone-releasing hormone, thyrotropin releasing hormone,alpha-melanocyte secreting hormone, substance P, oxytocin, bradykinin, neurotensin and angiotensin (Ag) I and II. Serum PEP activity was measured in the serum of 18 normal women, 21 anorexia nervosa and 21 bulimia nervosa women by means of a fluoremetric method. The Bulimic Investigatory Test, Edinburgh (BITE), the Eating Disorder Inventory (EDI) and the Hamilton Depression Rating Scale (HDRS) were scored. Serum PEP activity was significantly lower in patients with bulimia nervosa and anorexia nervosa, irrespective of the restricted or binging subtype, than in normal controls. There were significant and inverse correlations between serum PEP activity and the HDRS and BITE. In anorectic patients, but not in normal or bulimic patients, there was a significant correlation between serum PEP and body mass index. In bulimic patients, but not in normal or anorectic patients, there was a significant correlation between serum PEP and duration of illness. It is concluded that lowered serum PEP activity takes part in the pathophysiology of anorexia and bulimia nervosa. It is hypothesized that a combined dysregulation of PEP and neuroactive peptides, which are substrates of PEP, could be an integral component of eating disorders.

GP130 and c-kit signalling, initiated by the sIL-6R/IL-6 complex, is insufficient to expand the primitive adult bone marrow CD34+CD38- pre-CFU cell

It has previously been shown that gp130 and c-kit signalling synergize for the ex vivo expansion of human cord blood (CB) CD34+ haematopoietic progenitor cells. We were interested in evaluating this synergy within an ontogenetically different haematopoietic tissue [i.e. adult bone marrow (BM)] and on a more primitive progenitor subset (i.e. CD34+ CD38-cells), which are highly enriched for pre-colony forming unit (CFU) cells. These cells were plated out in a primary liquid culture supplemented with either interleukin (IL)-6+stem cell factor (SCF), IL-6+ SCF+soluble IL-6 receptor (sIL-6R), IL-6+SCF+sIL-6R+IL3+IL-1 or SCF+IL-3+IL-6+IL-1. Cell counting after liquid culture revealed an absolute expansion of 2.2-, 4.1-, 89.5- and 65.7-fold compared with initial cell input for the four-cytokine combinations, respectively. The secondary read-out assay revealed that this cell expansion in the liquid culture also resulted in CFU generation, with absolute cloning efficiencies of 0.002, 0.024, 12.13 and 7.73 (per cell initially present) for the respective cytokine combinations. These results indicate that gp130 and c-kit signalling alone (i.e. using IL6+SCF+sIL-6R), in terms of both cell number and CFU generation, insufficiently stimulate primitive adult BM CD34+CD38- haematopoietic cells in order to reach a CFU generation comparable with that obtained after multifactor stimulation. Adding sIL-6R to the multifactor stimulation and compared with this multifactor stimulation, a 1.7-fold synergy in terms of cell expansion and a 3.0-fold synergy in terms of CFU generation are obtained. The sIL-6R/IL-6 complex thus has a narrower spectrum of action on primitive adult BM CD34+CD38- cells than on CB CD34+ cells.

The effects of noradrenaline and alpha-2 adrenoceptor agents on the production of monocytic products

There are some reports that catecholamines may modulate the production of monocytic cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF alpha). The present study was carried out in order to examine the effects of noradrenaline (10(-5), 10(-6) and 10(-7) M), clonidine (10(-5), 10(-6) and 10(-7) M), an alpha2-adrenoceptor agonist, and yohimbine (10(-5), 10(-6) and 10(-7) M), an alpha 2-adrenoceptor antagonist, on the production of IL-6, the IL-1 receptor antagonist (IL-1RA) and TNF alpha by stimulated whole blood of normal humans. We measured the in vitro production of IL-6, TNF alpha and IL-1RA by stimulated (phytohemagglutinin+lipopolysaccharide), diluted whole blood of 16 normal volunteers. The results show that noradrenaline, 10(-5) M, significantly suppressed the production of IL-6; noradrenaline, 10(-5) and 10(-6) M, significantly suppressed the production of IL-1RA and TNF alpha; clonidine, 10(-5) M, significantly suppressed the production of TNF alpha; and yohimbine, 10(-5) and 10(-6) M, significantly suppressed the production of IL-1RA. It is concluded that (1) noradrenaline has significant negative immunoregulatory effects in humans through suppression of the production of (monocytic) proinflammatory cytokines, e.g. IL-6 and TNF alpha, and (2) the suppression of the production of TNF alpha may be related to alpha(2)-adrenoceptor-related mechanisms.

Suppressive effect of TRH and imipramine on human interferon-gamma and interleukin-10 production in vitro

It has been established that thyrotropin-releasing hormone (TRH) affects several aspects of immunoreactivity, e.g. production of pro-inflammatory cytokines, and enhances therapeutic efficiency of classic tricyclic antidepressants. On the other hand, it has been suggested that pro-inflammatory cytokines play a role in the etiology of depression, whereas the therapeutic efficacy of antidepressants is related to their negative immunoregulatory effect. In order to verify the hypothesis that the TRH-induced increase in the therapeutic efficiency of classic tricyclic antidepressants results from synergistic inhibitory effects of those two agents on the secretion of pro-inflammatory cytokines, we studied the effect of imipramine appliedjointly with TRH on the production of IFN-gamma and IL-10 by human whole blood cells stimulated in vitro by mitogens. A significant decrease in the production of IFN-gamma and IL-10 cytokines, by 36% and 34%, respectively, was observed in cells stimulated with mitogens and co-incubated with imipramine and TRH (either given at a dose of 10(-5) M). Under the same conditions, TRH alone did not change the production of those cytokines. Furthermore, imipramine alone decreased, not statistically significantly, though, the production of IFN-gamma. Hence our data only partly support the above-mentioned hypothesis, since TRH and imipramine applied jointly suppress the production of both the pro-inflammatory IFN-gamma and the anti-inflammatory IL-10 cytokines.

Molecular characterization of dipeptidyl peptidase activity in serum: soluble CD26/dipeptidyl peptidase IV is responsible for the release of X-Pro dipeptides

Dipeptidyl peptidase IV (DPPIV, EC 3.4.14.5) is a serine type protease with an important modulatory activity on a number of chemokines, neuropeptides and peptide hormones. It is also known as CD26 or adenosine deaminase (ADA; EC 3.5.4.4) binding protein. DPPIV has been demonstrated on the plasmamembranes of T cells and activated natural killer or B cells as well as on a number of endothelial and differentiated epithelial cells. A soluble form of CD26/DPPIV has been described in serum. Over the past few years, several related enzymes with similar dipeptidyl peptidase activity have been discovered, raising questions on the molecular origin(s) of serum dipeptidyl peptidase activity. Among them attractin, the human orthologue of the mouse mahogany protein, was postulated to be responsible for the majority of the DPPIV-like activity in serum. Using ADA-affinity chromatography, it is shown here that 95% of the serum dipeptidyl peptidase activity is associated with a protein with ADA-binding properties. The natural protein was purified in milligram quantities, allowing molecular characterization (N-terminal sequence, glycosylation type, CD-spectrum, pH and thermal stability) and comparison with CD26/DPPIV from other sources. The purified serum enzyme was confirmed as CD26.

Lower serum zinc in relation to serum albumin and proinflammatory cytokines in detoxified alcohol-dependent patients without apparent liver disease

Recently, it was reported that there may be an activation of the inflammatory response system in detoxified alcohol-dependent patients without apparent liver disease (AWLD). The aims of the present study were to examine serum zinc (Zn) concentrations, total serum protein (TSP) and patterns obtained in the electrophoretically separated protein fractions in relation to serum interleukin-6 (IL-6) and IL-8 concentrations in detoxified AWLD patients. Zn, TSP, SP electrophoresis, and serum IL-6 and IL-8 concentrations were determined in detoxified AWLD patients and age-matched healthy volunteers. Serum Zn, TSP and the serum concentrations of albumin (Alb) and the beta fraction were significantly lower in detoxified AWLD patients than in healthy volunteers. The percentage of the alpha2 fraction was significantly higher in detoxified AWLD patients. Lower serum Zn in detoxified AWLD patients was attributable to lowered serum Alb. Lower serum Alb was significantly and negatively correlated to increased serum IL-8. The percentage of the alpha1 and alpha2 fractions were significantly and positively related to serum IL-6 and IL-8. The results show that there is an in vivo activation of the inflammatory response system in detoxified AWLD patients and that lower serum Zn may be causally related to lower serum Alb.

Effects of serotonin and serotonergic agonists and antagonists on the production of interferon-gamma and interleukin-10

Serotonin (5-HT) is a neurotransmitter and an immune modulator. In vitro, antidepressants with a serotonergic mode of action have, at concentrations within the therapeutical range, negative immunoregulatory effects, i.e., they increase the production rate of interleukin-10 (IL-10), a negative immunoregulatory cytokine. We have hypothesized that part of these effects may be explained by the serotonergic activities of antidepressants on immunocytes. This study was carried out to examine the effects of 5-HT, p-chlorophenylalanine (PCPA), a 5-HT depleting agent, flesinoxan (a 5-HT1A agonist), m-chlorophenylpiperazine (mCPP; a 5-HT2A/2C agonist), and ritanserin (a 5-HT2A/2C antagonist) on the production rate of interferon-gamma (IFNgamma), a proinflammatory cytokine, and IL-10 by whole blood stimulated with polyclonal activators. The IFNgamma/IL-10 production ratio was computed, since this ratio reflects the pro- versus anti-inflammatory capacity of cultured whole blood. We found that: 1) 5-HT, 150 ng/mL, 1.5 microg/mL, and 15 microg/mL significantly decreased the IFNgamma/IL-10 ratio; 2) PCPA (5 microM) significantly suppressed the production of IFNgamma and IL-10; 3) flesinoxan (15 ng/mL; 1.5 microg/mL) had no significant effects on the production of the above cytokines; and 4) mCPP (2.7 microg/mL) and ritanserin (5.0 microg/mL) suppressed the IFNgamma/IL-10 ratio. It is concluded that intracellular 5-HT may be necessary for an optimal synthesis of IFNgamma and IL-10, and that extracellular 5-HT concentrations at or above serum values may suppress the production of the proinflammatory cytokine IFNgamma. The negative immunoregulatory effects of antidepressive drugs are probably not related to their serotonergic activities.

In humans, serum polyunsaturated fatty acid levels predict the response of proinflammatory cytokines to psychologic stress

BACKGROUND

Psychologic stress in humans induces the production of proinflammatory cytokines, such as interferon gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), and interleukin-6 (IL-6), and that of the negative immunoregulatory cytokine, IL-10. An imbalance of omega6 to omega3 polyunsaturated fatty acids (PUFAs) in the peripheral blood causes an overproduction of proinflammatory cytokines. The omega3 PUFAs reduce the production of proinflammatory cytokines.

METHODS

This study examines whether an imbalance in omega6 to omega3 PUFAs in human blood predicts a greater production of proinflammatory cytokines in response to psychologic stress. Twenty-seven university students had serum sampled a few weeks before and after as well as 1 day before a difficult oral examination. We determined the omega6 and omega3 fractions in serum phospholipids as well as the ex vivo production of IFN-gamma, TNF-alpha, IL-6, IL-10, and IL-5 by diluted whole blood stimulated with polyclonal activators.

RESULTS

Academic examination stress significantly increased the ex vivo, stimulated production of IFN-gamma, TNF-alpha and IL-10, and the IFN-gamma/IL-5 production ratio. Subjects with lower serum omega3 PUFA levels or with a higher omega6/omega3 ratio had significantly greater stress-induced TNF-alpha and IFN-gamma responses than subjects with higher serum omega3 PUFAs and a lower omega6/omega3 ratio, respectively. Subjects with lower serum omega3 PUFA levels or with a higher omega6/omega3 ratio had a significantly higher stress-induced increase in the IFN-gamma/IL-5 ratio than the remaining subjects.

CONCLUSIONS

Psychologic stress induces a Th-1-like or proinflammatory response in some subjects. An imbalance in the omega6 to omega3 PUFA ratio appears to predispose humans toward an exaggerated Th-1-like response and an increased production of monocytic cytokines, such as TNF-alpha, in response to psychologic stress. The results suggest that increased omega3 PUFA levels may attenuate the proinflammatory response to psychologic stress.

Plasma levels of interleukin-6, interleukin-10, and interleukin-1 receptor antagonist in depression: comparison between the acute state and after remission

There is now some evidence that major depression is accompanied by an immune response with an increased production of pro-inflammatory cytokines. The aim of the present study was to examine serum level of cytokines: interleukin-6 (IL-6), which is considered pro-inflammatory one and anti-inflammatory cytokines: interleukin 10 (IL-10), and interleukin-1 receptor antagonist (IL-1Ra) in acute clinical state of depression and after 6-week antidepressant treatment. Serum IL-6, IL-10, IL-1Ra levels were higher in the subjects with major depression than in normal controls although these results were not statistically significant. The mean score according to the Hamilton Depression Rating Scale (HDRS) in the patients significantly decreased during the 6 weeks of the study, demonstrating an overall improvement. Successful antidepressant treatment had no significant effect on serum level of this cytokines.

Immunosuppressive effects of clozapine and haloperidol: enhanced production of the interleukin-1 receptor antagonist

In schizophrenic patients, multiple immune abnormalities have been reported, including increased production of proinflammatory cytokines. There is some evidence that antipsychotic drugs may have immunosuppressive effects. The aim of this study was to examine the in-vitro effects of different concentrations of antipsychotic agents on cytokine production by human whole blood. We examined the effects of clozapine and haloperidol, 10(-4), 10(-6) and 10(-8)M, on the unstimulated and stimulated (lipopolysaccharide+phytohemagglutinin) production of interleukin-6 (IL-6), IL-10, interferon-gamma (IFNgamma), and the IL-1 receptor antagonist (IL-1RA). Clozapine, 10(-6) and 10(-8)M, and haloperidol, 10(-4), 10(-6), and 10(-8)M, significantly increased the unstimulated and stimulated production of IL-1RA. Clozapine 10(-6)M significantly increased the stimulated production of IFNgamma. Clozapine 10(-4)M significantly suppressed the unstimulated production of IL-6 and IL-1RA and the stimulated production of IL-6, IL-10, IFNgamma and IL-1RA. The results suggest that both clozapine and haloperidol, at concentrations within the therapeutic range, may exert immunosuppressive effects through an enhanced production of IL-1RA.

The in vitro immunosuppressive effects of moclobemide in healthy volunteers

BACKGROUND

Many studies have demonstrated that major depression is related to an activation of the inflammatory response system (IRS) with an increased production of proinflammatory cytokines. It has been shown that tricyclic antidepressants and serotonin reuptake inhibitors suppress the activation of the IRS in depression and have negative immunoregulatory effects in vitro. Little is known on the immune effects of moclobemide, a reversible monoamine oxidase A inhibitor.

METHODS

We examined, in nine normal volunteers, the in vitro effects of moclobemide on the production of interleukin-6 (IL-6), IL-8, tumor necrosis factor-alpha (TNFalpha), interferon-gamma (IFNgamma), IL-10 and the IL-1 receptor antagonist (IL-1RA) by diluted whole blood stimulated or not with lipopolysaccharide (LPS)+phytohemagglutinin (PHA).

RESULTS

Moclobemide 10(-3) and 10(-5) M significantly suppressed the unstimulated production of TNFalpha and IL-8, and significantly enhanced the stimulated-production of IL-10. The production of IL-6, IL-1RA and IFNgamma was not significantly affected either in the unstimulated or stimulated conditions.

CONCLUSIONS

Moclobemide has negative immunoregulatory capacities through inhibition of the production of proinflammatory cytokines, i.e. TNFalpha and IL-8, and through enhancement of the production of IL-10, an anti-inflammatory cytokine.

Pathogenesis of abnormal vaginal bacterial flora

OBJECTIVE

This study was undertaken to determine the relationships between microscopy findings on wet mounts, such as lactobacillary grade or vaginal leukocytosis, and results of vaginal culture, lactate and succinate content of the vagina, and levels of selected cytokines.

STUDY DESIGN

In a population of 631 unselected women seeking treatment at an obstetrics and gynecology outpatient clinic, vaginal fluid was obtained by wooden Ayre spatula for wet mounting and pH measurement, by high vaginal swab for culture, and by standardized vaginal rinsing with 2 mL 0.9% sodium chloride solution for measurements of lactate, succinate, interleukin 1beta, interleukin 8, leukemia inhibitory factor, and interleukin 1 receptor antagonist concentrations. Lactate and succinate levels were measured by gas-liquid chromatography and the cytokine concentrations were measured by specific immunoassays. Both univariate analysis (Student t test, Welch test, chi(2) test, and Fisher exact test) and multivariate regression analysis (Cox analysis) were used.

RESULTS

Increasing disturbance of the lactobacillary flora (lactobacillary grades I, IIa, IIb, and III) was highly correlated with the presence of Gardnerella vaginalis, Trichomonas vaginalis, enterococci, group B streptococci, and Escherichia coli. Vaginal pH and interleukin 8 and interleukin 1beta concentrations increased linearly with increasing lactobacillary grade, whereas lactate concentrations and the presence of epithelial cell lysis decreased. A similar pattern of associations with increasing leukocyte count was clear, but in addition there was an increase in leukemia inhibitory factor concentration. Multivariate analysis of vaginal leukocytosis, lactobacillary grades, and the presence of positive vaginal culture results showed that interleukin 1beta concentration was most closely related to the lactobacillary grade, leukemia inhibitory factor concentration was most closely related to the lactobacillary grade and positive culture results, interleukin 8 concentration was most closely related to positive culture results, and interleukin 1 receptor antagonist concentration was most closely related to vaginal leukocytosis and positive culture results. The concentration ratio of interleukin 1beta to interleukin 1 receptor antagonist remained stable, except when vaginal leukocytosis increased. In its most severe form, with >10 leukocytes per epithelial cell present, a decompensation of the vaginal flora with a collapse in interleukin 1beta and interleukin 1 receptor antagonist concentrations was seen, but there was a concurrent sharp increase in leukemia inhibitory factor concentration. This pattern was completely different from the course of the cytokine concentrations associated with a lactobacillary grade increase.

CONCLUSION

Both disturbed lactobacillary grade and the presence of increasing vaginal leukocytosis were correlated with lactobacillary substrate (lactate) concentration, pH, and the concentrations of a variety of cytokines. There was a remarkably linear increase in these cytokines as either leukocytosis or lactobacillary grade became more severe. In circumstances in which leukocytosis was extreme, however, interleukin 1beta was no longer produced but leukemia inhibitory factor concentrations increased. We speculate that in extreme inflammation the body tries to limit the damage that can be done by exaggerated cytokine production.

Effects of atypical antipsychotics on the inflammatory response system in schizophrenic patients resistant to treatment with typical neuroleptics

There is now some evidence that schizophrenia may be accompanied by an activation of the inflammatory response system (IRS) and that typical antipsychotics may suppress some signs of IRS activation in that illness. This study was carried out to examine (i) the serum concentrations of interleukin-6 (IL-6), IL-6 receptor (IL-6R), IL-1R antagonist (IL-1RA) and Clara Cell protein (CC16), an endogenous anticytokine, in nonresponders to treatment with typical neuroleptics and (ii) the effects of atypical antipsychotics on the above IRS variables. The above parameters were determined in 17 patients with treatment-resistant schizophrenia (TRS) to treatment with neuroleptics and in seven normal volunteers and 14 schizophrenic patients who had a good response to treatment with antipsychotic agents. Patients with TRS had repeated measurements of the IRS variables before and 2 and 4 months after treatment with atypical antipsychotics. Serum IL-6 was significantly higher in schizophrenic patients, irrespective of their response to typical antipsychotics, than in normal controls. Serum IL-1RA was significantly higher in the TRS patients than in controls, whereas responders took up an intermediate position. The serum concentrations of CC16 were significantly lower after treatment with atypical antipsychotics during 4 months than before treatment. It is concluded that (i) schizophrenia and, in particular, TRS is characterized by an activation of the monocytic arm of cell-mediated immunity and (ii) atypical antipsychotics may decrease the anti-inflammatory capacity of the serum in TRS patients.

Immune activation in the early puerperium is related to postpartum anxiety and depressive symptoms

The pathophysiology of the postpartum blues, common transient mood disorders in the first week postpartum, has remained elusive. Recently, however, it has been shown that depression and anxiety disorders are accompanied by activation of the inflammatory response system (IRS). This study was developed to determine whether the postnatal blues is associated with IRS activation. Serum concentrations of interleukin-6 (IL-6), IL-6 receptor (IL-6R), gp130 (the IL-6 signaling protein), IL-1R antagonist (IL-1RA) and leukemia inhibitory factor receptor (LIFR) were assayed in 22 nonpregnant women and in 91 pregnant women before delivery and 1 and 3 days after delivery. On each occasion the parturient women completed the State version of the Spielberger State-Trait-Anxiety-Inventory (STAI) and the Zung Depression Rating Scale (ZDS). Serum IL-6, IL-1RA and LIFR were significantly higher in pregnant women at the end of term than in nonpregnant women.

Effects of pregnancy and delivery on serum prolyl endopeptidase (PEP) activity: alterations in serum PEP are related to increased anxiety in the early puerperium and to postpartum depression

BACKGROUND

There is now some evidence that anxiety or anxiety disorders are related to increased activity of serum prolyl endopeptidase (PEP) and that major depression is related to lower serum PEP. The aims of the present study were to examine (i) the effects of pregnancy and delivery on serum PEP and (ii) the relationships between serum PEP and postpartum depression, anxiety in the early puerperium and a past history of depression.

METHODS

Serum PEP activity was measured in 11 healthy nonpregnant and in 98 pregnant women 3 days before delivery and 1 and 3 days after delivery. On the same occasions, pregnant females completed the Spielberger State Anxiety Inventory (STAI) and were divided into high and low anxiety responders, as defined by changes in the STAI. The presence of a previous depression and postpartum depression within 3 months of delivery was assessed by means of DSM-IV criteria.

RESULTS

Serum PEP activity was significantly higher 1 and 3 days after delivery than before. Women with a past history of depression as well as anxiety responders had significantly increased serum PEP activity over nonpregnant women and puerperae with a negative history and anxiety nonresponders, respectively. Parturients who developed a postpartum major, but not minor, depression had significantly lower serum PEP than parturients without postpartum depression. The results were controlled for maternal and labor variables, such as type of analgesia and delivery, induction of labor, breast feeding, parity, and duration of pregnancy and labor.

CONCLUSIONS

Our results show that, in puerperae, increased serum PEP is related to increased state anxiety in the early puerperium and that lowered serum PEP is related to a subsequent postpartum major depression.

INTERPRETATION

The results suggest that increased serum PEP may be related to postpartum anxious blues and that lowered serum PEP may predispose toward postpartum major depression.

Immunoendocrine findings in patients with eating disorders

Immune changes may occur in patients with anorexia nervosa (AN) or bulimia nervosa (BN), and a role for proinflammatory cytokines has been proposed in the pathogenesis of both disorders. We measured plasma levels of interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha (TNF-alpha), soluble forms of the cytokine receptor proteins gp130 and leukemia inhibitory factor receptor (LIF-R), the anti-inflammatory Clara cell 16-kD protein (CC16), prolactin (PRL), cortisol and 17beta-estradiol in 21 anorexic women, 21 bulimic women and 21 healthy females. As compared to healthy subjects, anorexics exhibited significantly increased plasma levels of gp130 and LIF-R, whereas bulimics had significantly decreased blood concentrations of CC16. No significant differences emerged in the blood levels of the remaining immune parameters. Both patient groups manifested higher plasma levels of cortisol and reduced plasma concentrations of PRL and 17beta-estradiol. In anorexics, a significant negative correlation was found between plasma levels of gp130 or LIF-R and the body mass index. These findings do not support the hypothesis that proinflammatory cytokines may play a pathogenetic role in eating disorders.

Inflammatory markers in younger vs elderly normal volunteers and in patients with Alzheimer's disease

BACKGROUND

Recently it has been reported that activation of the inflammatory response system (IRS) may play a role in the aging process and in the pathogenesis of the degenerative changes associated with Alzheimer's disease (SDAT). The aims of the present study were to examine the peripheral IRS in normal aging and in SDAT patients.

METHODS

Serum zinc (Zn), total serum protein (TSP), albumin (Alb), SP electrophoresis, and serum interleukin-6 (IL-6) and the stimulated production of tumor necrosis factor-alpha (TNFalpha) were determined in younger versus elderly healthy subjects and in SDAT patients vs. age-matched, healthy volunteers.

RESULTS

Serum Zn and Alb were significantly lower in elderly than in younger healthy volunteers and were significantly and inversely correlated with age. The production of TNFalpha was significantly higher in elderly than in younger healthy volunteers and was significantly and positively correlated with age. In SDAT patients, no significant changes in serum Zn or TNFalpha production could be found. Serum Alb was significantly lower and serum IL-6 and the alpha1 and alpha2 globulin fractions significantly higher in SDAT patients than in controls.

CONCLUSIONS

Activation of the IRS appears to accompany the normal aging process, i.e. lower serum Zn and Alb and increased TNFalpha production, as well as SDAT, i.e. lower serum Alb and increased serum IL-6 and alpha1 and alpha2 globulin fractions. The findings suggest that not all indicators of IRS activation in SDAT are related to those of the normal ageing process.

The fetomaternal dependency of cord blood interleukin-6

Interleukin-6 (IL-6) plays a major role in hematopoiesis, immune functioning, and the acute phase response. In umbilical cord blood, this cytokine was thought to be a marker of neonatal defense to stress and infection, however, neonatal IL-6 production is immature. We speculated that a maternal influence exists on neonatal IL-6, at least during uncomplicated deliveries. Of the 81 healthy parturients included in this study, 51 delivered vaginally, 20 with and 31 without epidural analgesia, and 30 underwent elective cesarean section, 20 with epidural and 10 with general anesthesia. Maternal blood was sampled on hospital admission and just after delivery. Neonatal blood was collected from the umbilical cord. A significant positive correlation was found between neonatal cord blood interleukin-6 levels and maternal serum IL-6 levels on admission (r = 0.57, p <0.001) and just after delivery (r = 0.79, p <0.001). This was not influenced by the type of delivery or anesthesia. Neonatal IL-6 levels were weakly negatively correlated with the duration of gestation and with the Apgar score 1 min after birth. A feto-maternal dependency of neonatal IL-6 on maternal serum IL-6 levels implies a priming or modulatory role of the maternal immune system on that of the neonate.

Decreased CD40 ligand induction in CD4 T cells and dysregulated IL-12 production during HIV infection

During HIV infection various cytokines are overproduced in early stages, whereas in advanced disease cytokines of the T helper 1 type (e.g. interferon-gamma (IFN-gamma)) are selectively deficient. During antigenic stimulation, the production of type-1 cytokines is enhanced by IL-12, secreted by antigen-presenting cells (APC) after their interaction with activated CD4 T cells. Two factors are essential in this process: priming APC with IFN-gamma and triggering the CD40 receptor on APC by CD40 ligand (CD40L). In view of the importance of this pathway, we compared its regulation in HIV-infected and control subjects. After cross-linking of the T cell receptor (TCR)/CD3 complex, the proportional expression of CD40L was similar on CD4+ T cells from controls and from patients with high circulating CD4 T counts (> 500/microl), but CD40L up-regulation was significantly reduced in patients with more advanced disease. Simultaneous triggering of the costimulatory receptor CD28 on T cells through its natural ligand CD80 partly corrected the CD40L defect in patients with intermediate CD4 T counts (200-500), but not in AIDS patients. Early production of IFN-gamma was preserved in lymphocytes from HIV+ patients. The expression of CD40 on peripheral monocytes from HIV+ subjects was increased in a disease stage-related fashion. Stimulation of mononuclear cells through cell-bound CD40L and soluble IFN-gamma induced significantly higher IL-12 in cultures from patients with > 200 circulating CD4 T cells, whereas IL-12 production was marginally decreased in cultures from patients with < 200 CD4 T cells, compared with healthy control cultures. In conclusion, our data suggest that impaired CD40L induction on CD4 T cells contributes to deficient type-1 responses through decreased IL-12 production in AIDS infection, whereas enhanced CD40-mediated IL-12 production in less advanced stages might contribute to increased levels of various cytokines in early disease