Evidence for a positive correlation between serum cortisol levels and IL-1beta production by peripheral mononuclear cells in anorexia nervosa

A transdiagnostic and diagnostic-specific approach on inflammatory biomarkers in eating disorders: A meta-analysis and systematic review

Eating disorders (EDs) are severe mental illnesses with a multifactorial etiology and a chronic course. Among the biological factors related to pathogenesis and maintenance of EDs, inflammation acquired growing scientific interest. This study aimed to assess the inflammatory profile of EDs, focusing on anorexia nervosa, bulimia nervosa, and including for the first time binge eating disorder. A comprehensive research of existing literature identified 51 eligible studies for meta-analysis, comparing levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), osteoprotegerin (OPG), soluble receptor activator of nuclear factor kappa-B ligand (sRANKL), interleukin-1β (IL-1β), and interleukin-10 (IL-10) between patients with EDs and healthy controls (HCs). The systematic review explored other inflammatory biomarkers of interest, which did not meet the meta-analysis criteria. Results revealed significantly elevated levels of TNF-α, OPG, sRANKL, and IL-1β in patients with EDs compared to HCs. Additionally, the results highlighted the heterogeneity of inflammatory state among patients with EDs, emphasizing the need for further research into the association between inflammatory biomarkers and psychopathological correlates. This approach should transcend categorical diagnoses, enabling more precise subcategorizations of patients. Overall, this study contributed to the understanding of the inflammatory pathways involved in EDs, emphasizing potential implications for diagnosis, staging, and targeted interventions.

Immunoinflammatory processes: Overlapping mechanisms between obesity and eating disorders?

Obesity and eating disorders are conditions that involve eating behaviors and are sometimes comorbid. Current evidence supports alterations in immunoinflammatory processes in both obesity and eating disorders. A plausible hypothesis is that immunoinflammatory processes may be involved in the pathophysiology of obesity and eating disorders. The aim of this review is to highlight the link between obesity and eating disorders, with a particular focus on immunoinflammatory processes. First, the relation between obesity and eating disorders will be presented, followed by a brief review of the literature on their association with immunoinflammatory processes. Second, developmental factors will be discussed to clarify the link between obesity, eating disorders, and immunoinflammatory processes. Genetic and epigenetic risk factors as well as the potential roles of stress pathways and early life development will be presented. Finally, implications of these findings for future research are discussed. This review highlighted biological and developmental aspects that overlap between obesity and EDs, emphasizing the need for biopsychosocial research approaches to advance current knowledge and practice in these fields.

A systematic review of in vitro cytokine production in eating disorders

BACKGROUND

Eating disorders (EDs) have been associated with alterations in cytokine concentrations and production. This review examines whether in vitro cytokine production (i) is altered in people with EDs compared to healthy participants; and (ii) changes in response to treatment?

METHODS

Using PRISMA guidelines, we systematically reviewed articles reporting group comparisons or longitudinal assessments of spontaneous and/or stimulated cytokine production in vitro in people with EDs.

RESULTS

Twelve studies were included. Cross-sectional results were mixed in anorexia nervosa. Only one study measured cytokine production in bulimia nervosa. Two longitudinal studies showed that daily yoghurt consumption increases phytohemagglutinin-stimulated interferon-γ production in anorexia nervosa.

CONCLUSION

The mixed results could be accounted for by variations in experimental design. Our findings suggest that cytokine production could possibly be modulated through dietary interventions. However, due to the methodological heterogeneity and shortcomings of the included studies, it seems unreasonable to draw further conclusions.

Adipokines, cortisol and cytokine alterations in recent onset anorexia nervosa. A case-control study

INTRODUCTION

Psychological and neuroendocrine alterations are typical characteristics in anorexia nervosa patients. The role of adipokines and cytokines as mediators of body systems' adaptations to the patients' abnormal eating behavior is not well understood. The duration of disease seems to be a determinant of nutritional status and associated hormone changes. We aimed to assess whether alterations in adipokines, cytokines and cortisol do already exist in patients with a recent disease onset by means of a case-control study.

METHODS

Forty-one adolescent female patients on their first-episode and diagnosed with anorexia nervosa, were matched by age and socioeconomic status (SES) (1:1) with healthy girls. Leptin, soluble leptin receptor (sOB-R), adiponectin, cortisol, and the cytokines IL-1β, IL-2, IL-6 and TNF-α were examined.

RESULTS

The results showed reduced leptin and increased sOB-R and cortisol levels in AN patients. Adiponectin was also increased but opposite to the previous biomarkers did not correlate with BMI Z-score. Serum TNF-α and IL-2 showed significantly lower and higher values, respectively, in the AN patients than in the controls. Cortisol showed the strongest correlation with sOB-R (r=0.436; P=0.005).

CONCLUSIONS

Our study confirms previous findings on adipokine and cortisol alterations in AN patients, while overall cytokine results did not show a clear disruption in AN patients with short disease duration. The results highlight the need to disentangle the role of the sOB-R in the interactions between leptin and cortisol secretion.

Genetic risk factors for eating disorders: an update and insights into pathophysiology

Genome-wide-association studies (GWASs), epigenetic, gene-expression and gene-gene interaction projects, nutritional genomics and investigations of the gut microbiota have increased our knowledge of the pathophysiology of eating disorders (EDs). However, compared with anorexia nervosa, genetic studies in patients with bulimia nervosa and binge-eating disorder are relatively scarce, with the exception of a few formal genetic and small-sized candidate-gene-association studies. In this article, we review important findings derived from formal and molecular genetics in order to outline a genetics-based pathophysiological model of EDs. This model takes into account environmental and nutritional factors, genetic factors related to the microbiome, the metabolic and endocrine system, the immune system, and the brain, in addition to phenotypical traits of EDs. Shortcomings and advantages of genetic research in EDs are discussed against the historical background, but also in light of potential future treatment options for patients with EDs.

The increased risk for autoimmune diseases in patients with eating disorders

Objective

Research suggests autoimmune processes to be involved in psychiatric disorders. We aimed to address the prevalence and incidence of autoimmune diseases in a large Finnish patient cohort with anorexia nervosa, bulimia nervosa, and binge eating disorder.

Methods

Patients (N = 2342) treated at the Eating Disorder Unit of Helsinki University Central Hospital between 1995 and 2010 were compared with general population controls (N = 9368) matched for age, sex, and place of residence. Data of 30 autoimmune diseases from the Hospital Discharge Register from 1969 to 2010 were analyzed using conditional and Poisson regression models.

Results

Of patients, 8.9% vs. 5.4% of control individuals had been diagnosed with one or more autoimmune disease (OR 1.7, 95% CI 1.5–2.0, P<0.001). The increase in endocrinological diseases (OR 2.4, 95% CI 1.8–3.2, P<0.001) was explained by type 1 diabetes, whereas Crohn's disease contributed most to the risk of gastroenterological diseases (OR 1.8, 95% CI 1.4–2.5, P<0.001). Higher prevalence of autoimmune diseases among patients with eating disorders was not exclusively due to endocrinological and gastroenterological diseases; when the two categories were excluded, the increase in prevalence was seen in the patients both before the onset of the eating disorder treatment (OR 1.5, 95% CI 1.1–2.1, P = 0.02) and at the end of the follow-up (OR 1.4, 95% CI 1.1–1.8, P = 0.01).

Conclusions

We observed an association between eating disorders and several autoimmune diseases with different genetic backgrounds. Our findings support the link between immune-mediated mechanisms and development of eating disorders. Future studies are needed to further explore the risk of autoimmune diseases and immunological mechanisms in individuals with eating disorders and their family members.

The expression of cytokines and chemokines in the blood of patients with severe weight loss from anorexia nervosa: an exploratory study

Anorexia nervosa (AN) is a serious, potentially life-threatening disorder characterized by severe weight loss, dysregulated eating, and often excessive exercise. While psychiatric illnesses such as depression are associated with increased levels of pro-inflammatory mediators, evidence for such disturbances in patients with AN has been less clear. In an exploratory study of possible disturbances in immune responses in AN, we assayed a panel of cytokines and chemokines in the blood of patients undergoing inpatient treatment, testing the hypothesis that metabolic disturbances in this disease would lead to a pattern of immune disturbances distinct from that of other psychiatric diseases. For this purpose, we evaluated patients by the Beck Depression Inventory-II (BDI-II) and the Eating Disorders Examination-Questionnaire and assessed cytokines and chemokines by enzyme-linked immunosorbent assays. Patients reported a moderate level of depression (mean BDI-II = 22.6) but exhibited few immunologic abnormalities of the kind associated with major depressive disorder [e.g., increased interleukin (IL)-6]; RANTES showed the most frequent elevations and was increased in 4 of the patients studied. Together, these findings suggest that features of AN such as loss of adipose tissue and excessive exercise may attenuate cytokine production and thus modulate the experience of illness that impacts on core features of disease.

NLRP3 inflammasome is activated in mononuclear blood cells from patients with major depressive disorder

INTRODUCTION

Major depressive disorder (MDD) is a very prevalent disease which pathogenic mechanism remains elusive. There are some hypotheses and pilot studies suggesting that cytokines may play an important role in MDD. In this respect, we have investigated the role of NLRP3 inflammasome complex in the maturation of caspase-1 and the processing of its substrates, IL-1β and IL-18, in blood cells from MDD patients.

METHODS

Forty MDD patients were selected for this study, twenty without treatments and twenty treated with amitriptyline, a common tricyclic antidepressant. Blood samples from twenty healthy volunteers were included in the study. The inflammasome activation was studied by Western blot and real-time PCR of NLRP3 and caspase 1 and serum levels of IL-1β and 18.

RESULTS

We observed increased gene expression of NLRP3 and caspase-1 in blood cells, and increased serum levels of IL-1β and IL-18 in non-treated patients. IL-1β and IL-18 correlated with Beck Depression Inventory (BDI) scores of MDD patients. Interestingly, amitriptyline treatment reduced NLRP3 and caspase-1 gene expression, and IL-1β and IL-18 serum levels. As it is well established that oxidative stress is associated with NLRP3 inflammasome activation, we next studied mitochondrial ROS and lipid peroxidation (LPO) levels in MDD patients. Increased levels of mitochondrial ROS and LPO were observed in MDD patients, however oxidative damage was higher in MDD patients treated with amitriptyline.

CONCLUSIONS

These findings provide new insight into the pathogenesis of MDD and the effects of amitriptyline treatment on NLRP3 inflammasome activation and IL-1β and IL-18 serum levels.

Tumour necrosis factor alpha and oxidative stress as maintaining factors in the evolution of anorexia nervosa

OBJECTIVE

Aim of the study was to evaluate tumour necrosis factor α (TNF-α) axis and oxidative status in patients with anorexia nervosa (AN) seeking a possible correlation with both nutritional status and evolution of the disease.

SUBJECTS AND METHODS

Thirty-nine consecutive women with AN and an age-matched healthy control group were studied. Patients were 26±9 yr, with a body mass index (BMI) of 13.9±2 kg/m(2). TNF-α, its receptors TNF-R55 and TNF-R75, and oxidative status markers (selenium, ascorbic/ dehydroascorbic acid, retinol, α-tocopherol, selenium-dependent gluthatione peroxidase, reduced/oxidated gluthatione) were measured. A correlation with both nutritional indexes (body weight, BMI, albumin, prealbumin, transferrin, lymphocyte count) and disease duration was investigated. Pearson's correlation and unpaired Student's t-test were used to compare patients and controls.

RESULTS

TNF-α and oxidative status markers were significantly higher in patients than controls and TNF-α was directly related to dehydroascorbic acid (p<0.05). Both TNF-R55 and TNF-R75 were higher in patients with duration of disease longer than one year as compared to controls and patients with shorter duration. Receptors inversely correlated with BMI (p<0.05 and p<0.01) and directly with disease duration (p<0.05). Inverse correlation between disease duration and BMI was present (p<0.01).

CONCLUSIONS

The study showed activation of TNF-α axis and oxidative stress in AN patients, as well as correlation between the two systems. Due to the correlation between TNF receptors and both BMI and disease duration, a possible role of pro-inflammatory cytokines in the evolution of the eating disorder is suggested.

Immunogenicity and safety of H1N1 vaccination in anorexia nervosa--results from a pilot study

OBJECTIVE

In anorexia nervosa (AN) patients immunologic alterations are known, although their clinical significance remains a matter of debate. Currently, no recommendation can be given on the safety and immunogenicity of indicated vaccinations in this malnourished population.

METHOD

In this exploratory study, 10 AN patients' (eight female, two male, mean age 31.1 years, SD 16.3 years; mean BMI 14.8 kg/m(2), SD 1.6 kg/m(2)) antibody levels against H1N1 influenza were measured before vaccination, and were followed-up for two and three weeks after vaccination. They were compared with the immunological response in normal weight population, as reported in the literature. Clinical and socio-demographical data were collected.

RESULTS

In the AN group, H1N1 vaccination showed to be sufficiently immunogenic and safe, comparable to published data of normal weight population.

DISCUSSION

The findings provide preliminary evidence that vaccination seems recommendable even in extremely underweight AN patients. Further studies are needed to corroborate the present findings.

Immunological disturbance and infectious disease in anorexia nervosa: a review

OBJECTIVE

Severely malnourished patients with anorexia nervosa (AN) are reported to show fewer symptomatic viral infections and a poorer response to bacterial infection than controls. They are also reported to show mild immune system changes, although the relevance of these to altered infection disease presentation in AN and AN pathophysiology is unknown. Thus, in this paper, we suggest a range of immune system changes that might underpin these altered responses to common pathogens, and review a number of recent infectious disease findings for their utility in explaining the pathophysiology of AN.

METHODS

A systematic review of the literature pertaining to immunity and infectious disease in AN was performed.

RESULTS

AN is associated with leucopenia, and the increased spontaneous and stimulated levels of proinflammatory cytokines [i.e. interleukin (IL)-1β, IL-6 and tumour necrosis factor α). A range of less consistent findings are also reviewed. Most of these data were not controlled for length of illness, degree of malnutrition, micronutrient or vitamin deficiencies or recent refeeding and starvation.

CONCLUSION

Cytokine disturbances have been suggested to be causally related to AN symptomatology and pathophysiology of AN, although the evidence supporting this assertion is lacking. Immune and cytokine changes in AN do, however, occur in association with a decreased incidence of symptomatic viral infection, decreased clinical response to bacterial infection leading to delayed diagnosis and increased morbidity and mortality associated with the infections.

Malnutrition induces dissociated changes in lymphocyte count and subset proportion in patients with anorexia nervosa

OBJECTIVE

The effect of nutritional state on lymphocytes in patients with anorexia nervosa (AN) was studied.

METHOD

We studied total lymphocyte count (TLC), lymphocyte subsets, and nutritional markers [body mass index (BMI), insulin-like growth factor-1 (IGF-I)], and serum zinc concentration) in 33 patients with AN and 10 healthy controls.

RESULTS

TLC positively correlated with BMI (r = .680, p < .001), IGF-I (r = .609 p < .001), and zinc (r = .589, p < .001). The CD4+ T-lymphocyte (CD4) proportion correlated negatively with BMI (r = -.301, p = .05) and IGF-I (r = -.346, p = .023), counteracting the effect of malnutrition on TLC. However, because this increase in CD4 proportion was weak, patients with very severe malnutrition (indicated by serum zinc less than 40 microg/dL) had critically low CD4 counts of less than 200 cells/microL.

CONCLUSION

Our findings suggest that lymphocyte counts and subset proportion change in an opposite manner in patients with AN, and that decrease in serum zinc levels is nutrition-related.

Urinary steroids in young women with eating disorders

Urinary steroid components were measured after enzyme hydrolysis and methoxym-silyl derivatization by capillary gas chromatography in young women with eating disorders. Using three internal standards, programmed temperature from 50 to 300 degrees C and flame ionization detection, on ULTRA-1 capillary column the separation of 28 steroid components is possible. Fifteen young women with different eating disorders, i.e. anorexia nervosa, bulimia nervosa and bulimarexia (aged 16-28 years) and 15 healthy women (aged 22-26 years) collected 24-h urine. A significant decrease of dehydroepiandrosterone (p<0.05) and a significant elevation of the stress marker allo-tetrahydrocorticosterone (p<0.05) were observed in the patients with compared to the controls. Among the patients two groups were defined due to a significant difference in the content of the cortisol metabolites compared to each other and to controls (p<0.01). The results confirm the role of dehydroepiandrosterone in eating disorders. The increased level of the stress marker allo-tetrahydrocorticosterone refers to the involvement of stress in these diseases, but the relevance of hormone alteration to the pathophysiology of eating disorders remains to be elucidated. The reason of the differences in cortisol metabolites levels in some patients needs further investigations.

Changes in cytokine production and impaired hematopoiesis in patients with anorexia nervosa: the effect of refeeding

The changes in cytokines and hormones involved in hematopoiesis were studied in the serum of 7 girls with anorexia nervosa, 15-24 yr old, on admission and after 5% and 10% weight gain. Hematopoiesis was studied by in-vitro culturing of circulating granulocyte-macrophage colony forming cells and erythroid burst forming cells. Nutritional status was studied by anthropometric measurements and resting energy expenditure. On admission, granulocyte-macrophage colony forming cells and erythroid burst forming cells were significantly lower than in age-matched controls and increased significantly along weight gain. Blood leptin and erythropoietin levels increased significantly with weight gain. TNF-alpha levels tended to decrease while IL-1beta levels were lower than in the controls on admission (p <0.05) and did not change significantly during weight gain. IL-3, GM-CSF and IL-6 were undetected on admission or along weight gain. The changes in granulocyte-macrophage colony forming cells and erythroid burst forming cells positively correlated with changes in resting energy expenditure and fat free mass. These results may suggest that undernutrition affects hematopoiesis as indicated by the reduction of hematopoietic progenitor cells before treatment and the significant increase with weight gain. The changes in the levels of hormones and cytokines known to be involved in hematopoiesis along refeeding may suggest a role for these factors in anorexia nervosa.

Two young female patients with anorexia nervosa complicated by Mycobacterium tuberculosis infection

Patients with anorexia nervosa (AN) seldom present with infectious illness, despite malnutrition-induced immunodeficiency. We described two young women who had a long-standing history of severe emaciation and pulmonary or lymph node tuberculosis discovered during the treatment of AN. Both patients reported a positive history of BCG vaccination. Contact tracing failed to reveal sources of infection, although the tuberculosis was considered transferred. Since the decline of notification rates for tuberculosis have been stagnant and outbreaks in schools or hospitals have been increasing in Japan, special attention must be given to the possibility of opportunistic infections in AN patients.

The adrenal sensitivity to ACTH stimulation is preserved in anorexia nervosa

Hyperactivity of hypothalamus-pituitary-adrenal (HPA) axis in anorexia nervosa (AN) has been demonstrated and is likely to reflect a central nervous system (CNS)-mediated effect of starvation. Alterations in the adrenal response to ACTH in AN have also been reported by some authors. In order to define the adrenal sensitivity to ACTH in this condition, we studied cortisol (F), aldosterone (A) and DHEA responses to the sequential administration of low and supramaximal ACTH 1-24 doses (0.06 microg/m2 ACTH 1-24 iv at 0 min and 250 microg ACTH 1-24 iv at +60 min, respectively) in 10 young women with AN [ANW, age 21.2 +/- 0.9 yr, body mass index (BMI) 15.7 +/- 0.6 kg/m2]. The results in this group were compared with those recorded in 10 healthy normal women (HW, 23.4 +/- 1.1 yr, 21.9 +/- 0.9 kg/m2). In ANW urinary F levels were similar to those in HW. Basal serum F, A and DHEA levels in ANW were not significantly different from those in HW. In HW the lowest ACTH dose induced a significant (p<0.05) increase of F, A and DHEA. The maximal ACTH dose induced F, A and DHEA increases greater (p<0.05) than those induced by the lowest ACTH dose. In ANW both ACTH doses induced significant (p<0.05) F and DHEA increases which were not significantly different from those in HW, though a trend toward a lower cortisol response after ACTH 0.06 microg/m2 in ANW was present. Like in HW, in ANW the maximal ACTH dose induced F and DHEA increases greater (p<0.01) than those induced by the lowest dose. Unlike HW, in ANW A levels did not increase after the lowest ACTH dose while they increased after the maximal one overlapping the response in HW. In conclusion, the cortisol and DHEA responses to a very low and a supra-maximal ACTH dose in patients with AN were similar to those in healthy subjects, indicating that the sensitivity to ACTH of the fasciculata and reticularis adrenal zones is preserved in this condition. On the other hand, a reduced sensitivity to ACTH of the glomerularis adrenal zone in patients with AN is suggested by the lack of aldosterone response to the lowest corticotropin dose.

Cytokine mRNA expression patterns in the disease course of female adolescents with anorexia nervosa

Anorexia nervosa (AN) is a serious eating disorder characterized by extreme weight loss and abnormalities of the neuroendocrine and immune systems. Cytokines have been discussed to be involved in the pathomechanisms underlying cachexia. Therefore our study aimed at examining the mRNA expression pattern of tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), interleukin-6 (IL-6) and interleukin-10 (IL-10) in whole blood of 11 female AN patients and 10 age and sex matched normal weight control subjects using a sensitive quantitative polymerase chain reaction (PCR) method. We found a significant increase in TNF-alpha and IL-6 mRNA expression in anorectic patients at admission (mean BMI 14.8 +/- 1.3) when compared to controls. During follow-up, the expression of TNF-alpha mRNA remained significantly higher in formerly anorectic patients (mean BMI 18.7 +/- 0.5) while IL-6 mRNA expression decreased. We interpret our results as suggesting that TNF-alpha may contribute to metabolic abnormalities in anorexia nervosa even after goal BMI is achieved.

Involvement of cytokines in eating disorders: a critical review of the human literature

A number of findings from clinical and animal studies indicate that pro-inflammatory cytokines may play roles in eating disorders. The measurement of pro-inflammatory cytokines (IL-1, IL-6, TNFalpha), which are known to decrease food intake, provides highly variable data from which firm conclusions cannot be drawn. In most of the longitudinal studies where pro-inflammatory cytokines have been shown to be impaired in anorexia or bulimia nervosa, a return to normal values was observed after renutrition. However these findings do not exclude the possibility that pro-inflammatory cytokines might be overproduced in specific brain areas and act locally without concomitantly increased serum or immune production. It was also pointed out that the production of the major type-1 cytokines (especially IL-2) was depressed in anorexia nervosa. It remains unclear whether this is due to undernutrition or to a specific underlying cause common to eating disorders. The impaired cytokine profile observed in eating disorders could be related to several factors including impaired nutrition, psychopathological and neuroendocrine factors. More particular attention should be devoted to the deregulation of the anti/pro-inflammatory balance. Deregulation of the cytokine network may be responsible for medical complications in eating disorder patients who are afflicted with chronic underweight.

Hypothalamic-pituitary-adrenal axis function and cytokine production in multiple sclerosis with or without interferon-beta treatment

OBJECTIVES

Pro-inflammatory cytokines mediate brain damage in multiple sclerosis (MS); they can also influence the hypothalamic-pituitary-adrenal (HPA) axis function. We evaluated the possible abnormalities of HPA axis function in relapsing-remitting MS (RR-MS).

MATERIAL AND METHODS

IFN-gamma, TNF-alpha and IL-6 production by ex-vivo lymphocytes from 10 normal volunteers and 10 RR-MS patients before and during IFN-beta therapy was assessed; pituitary-adrenal function was evaluated by means of CRH and ACTH stimulation tests.

RESULTS

In untreated patients the production of IFN-gamma, TNF-alpha, IL-6 was increased, and was significantly decreased by IFN-beta. Neither basal, nor stimulated ACTH, cortisol, DHEA, DHEAs, 17-alpha-OH-progesterone levels differed between controls and RR-MS patients, both before and during treatment. Moreover, no correlation was found between endocrine and immune parameters.

CONCLUSION

In MS the HPA axis function seems normal and not influenced by IFN-beta treatment. This result is discussed in relation to the increased production of pro-inflammatory cytokines found in this disease.

Social stress in anorexia nervosa: a review of immuno-endocrine relationships

Anorexia nervosa (AN) patients have difficulty in establishing social contacts, leading to tension, anxiety and full-blown stress reactions. Stress hormones are chronically increased in AN, while immune function, which is involved in physical and psychological coping capacities, is mostly unimpaired. We examined immune function in a group of anorexics by measuring the T-lymphocyte proliferative response to stimulation with phytohemagglutinin (PHA), before and after in vivo acute administration of corticotropin-releasing hormone (CRH), to mirror a stress reaction. The responses of anorexics, before and after CRH stimulation, did not differ from those of controls. In a second group of anorexics, we measured plasma concentrations of interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) before and after psychopharmacological (fluoxetine, amineptine) therapy. Basal values of the cytokines were not different in patients and controls, and did not change during therapy. In the same patients, we measured basal concentrations of soluble IL-1 beta receptor antagonist (s-IL-1 beta-RA), soluble IL-6 receptor (sIL-6-R) and soluble TNF-alpha receptors I and II (sTNF-alpha-R-I and -II). S-IL-1 beta-RA and sTNF-alpha-R-I and -II levels were not different in patients and controls, while those of s-IL-6-R were lower than normal in anorexics. The normality of most of the immune parameters in our anorexics, in basal conditions, after a stressful stimulation and after pharmacological manipulation of neurotransmitters suggests that the well-known interrelation among immune, neuroendocrine and central nervous system functions is not maintained in AN, the immune system being somehow unresponsive to stimuli.