Immune-metabolic profiling of anorexic patients reveals an anti-oxidant and anti-inflammatory phenotype

Comparison of Adiponectin Levels in Anorexia Nervosa, Bulimia Nervosa, Binge-Eating Disorder, Obesity, Constitutional Thinness, and Healthy Controls: A Network Meta-Analysis

Adiponectin is a protein hormone that is produced and secreted primarily by adipose tissue. The levels of adiponectin in those with eating disorders, obesity, and healthy controls have been extensively studied. However, the general picture of the differences in adiponectin levels across the mentioned conditions is still unclear and fragmented. In this study, we pooled previous studies and performed a network meta-analysis to gain a global picture of comparisons of adiponectin levels across eating disorders, obesity, constitutional thinness, and healthy controls. Electronic databases were searched for anorexia nervosa, avoidant restrictive food intake disorder, binge-eating disorder, bulimia nervosa, healthy controls, night eating syndrome, obesity, and constitutional thinness in studies where adiponectin levels were measured. A total of 4262 participants from 50 published studies were included in the network meta-analysis. Adiponectin levels were significantly higher in participants with anorexia nervosa than in healthy controls (Hedges' g = 0.701, p < 0.001). However, adiponectin levels in constitutionally thin participants were not significantly different from those of healthy controls (Hedges' g = 0.470, p = 0.187). Obesity and binge-eating disorder were associated with significantly lower adiponectin levels compared to those of healthy controls (Hedges' g = -0.852, p < 0.001 and Hedges' g = -0.756, p = 0.024, respectively). The disorders characterized by excessive increases or decreases in BMI were associated with significant changes in adiponectin levels. These results suggest that adiponectin may be an important marker of severely disequilibrated homeostasis, especially in fat, glucose, and bone metabolisms. Nonetheless, an increase in adiponectin may not simply be associated with a decrease in BMI, as constitutional thinness is not associated with a significant increase in adiponectin.

Clinical and Peripheral Biomarkers in Female Patients Affected by Anorexia: Does the Neutrophil/Lymphocyte Ratio (NLR) Affect Severity?

Anorexia Nervosa (AN) is a disabling disorder characterized by extreme weight loss and frequent chronicization, especially in its most severe forms. This condition is associated with a pro-inflammatory state; however, the role of immunity in symptom severity remains unclear. Total cholesterol, white blood cells, neutrophils, lymphocytes, platelets, iron, folate, vitamin D and B12 were dosed in 84 female AN outpatients. Mildly severe (Body Mass Index-BMI ≥ 17) versus severe (BMI < 17) patients were compared using one-way ANOVAs or χ² tests. A binary logistic regression model was run to investigate the potential association between demographic/clinical variables or biochemical markers and the severity of AN. Patients with severe anorexia (compared to mild forms) were older (F = 5.33; p = 0.02), engaged in more frequent substance misuse (χ² = 3.75; OR = 3.86; p = 0.05) and had a lower NLR (F = 4.12; p = 0.05). Only a lower NLR was predictive of severe manifestations of AN (OR = 0.007; p = 0.031). Overall, our study suggests that immune alterations may be predictive of AN severity. In more severe forms of AN, the response of the adaptive immunity is preserved, while the activation of the innate immunity may be reduced. Further studies with larger samples and a wider panel of biochemical markers are needed to confirm the present results.

Association of gut-specific non-inflammatory T lymphocytes with chronic anorexia nervosa and constitutional thinness

OBJECTIVE

Previous studies of AN showed low-grade inflammation. Are low-grade inflammation and circulating lymphocytes associated with chronic conditions?

METHOD

Peripheric blood cytokines were measured using Luminex™ technology in a chronic AN cohort (mean = 67.42 months), compared to Constitutional Thinness (CT), Constitutional Obesity (CO), and Healthy Controls (HC). Secondarily a prospective cohort of chronic AN (mean = 54.11 months) was recruited to compare the functional lymphocyte profile in blood by flow cytometry to CT and HC.

RESULTS

In the AN group, most cytokine concentrations were lower than in CT and HC groups. The IL-23 (98.02 pg/ml) was elevated related to HC and CO, and the IL-10 (4.178 pg/ml) was elevated versus CO. In the CT group, IL-9 (0.06216 pg/ml) was elevated compared to AN. The AN group had high Treg (9.259% of CD4⁺ ) and CD8⁺ Integrinβ7⁺ (9.552% of CD3⁺ ) versus HC for lymphocyte populations. In CT group, elevated Treg (9.7% of CD4⁺ ) elevated percentage of CD4⁺ CCR9⁺ (5.867% of CD3⁺ ) and CD8⁺ Integrinβ7⁺ (10.21% of CD3⁺ ) were found versus HC.

CONCLUSIONS

The chronic state of AN and CT is surprisingly non-inflammatory with elevated Treg cells. These results suggest that maintaining a dysregulated response to intestinal antigens may contribute to maintaining AN.

Adiponectin in anorexia nervosa and its modifiers: A meta-regression study

OBJECTIVE

Adiponectin, which is secreted from adipose tissue, is a protein hormone. Although a large body of studies have found that circulating adiponectin levels increase in anorexia nervosa (AN) and caloric restriction, the effect of subtypes of AN and modifiers of adiponectin in AN are not yet known.

METHODS

A systematic search of electronic databases was performed using the search terms "adiponectin," "anorexia nervosa," and "eating disorder" up to January 2021. All studies published in peer-reviewed journals, which included cases and control groups, were selected. The main outcome was the pooled standardized mean difference (SMD) in adiponectin levels between cases and controls, using the random-effects model. Modifiers of SMD were tested via meta-regression. Heterogeneity and publication bias were evaluated.

RESULTS

Thirty-four studies met all eligibility criteria. The total sample of AN participants (Hedges' g = .765, p < .0001), and specifically the binge-eating/purging (Hedges' g = 1.211, p < .00001) and restrictive subtypes (Hedges' g = .913, p < .00001) of AN have increased adiponectin plasma levels compared with healthy controls. Meta-regression determined that insulin, IGF-1, BMI, triglyceride, resistin, glucose, IL-6 levels are significant modifiers of adiponectin levels.

DISCUSSION

Compared with controls, adiponectin levels are higher in AN overall, and specifically in the binge-eating/purging and the restrictive AN subtypes. Many of metabolic parameters of glucose metabolism and pro-inflammatory molecules modify the relationship between AN and adiponectin levels. Adipose tissue is important to maintain metabolic stability.

PUBLIC SIGNIFICANCE

Anorexia nervosa is a psychiatric disorder associated with a severe decrease in body weight and multiple metabolic abnormalities, including an increase in the hormone adiponectin. In this paper, we used meta-analysis, a powerful statistical method, to aggregate data from 34 rigorously selected research reports. This enabled us to understand the value of adiponectin to differentiate clinical subtypes of anorexia nervosa and the relations between adiponectin and other important metabolic parameters.

Growth factors in anorexia nervosa: a systematic review and meta-analysis of cross-sectional and longitudinal data

OBJECTIVES

Growth factors are signalling molecules that play roles in the survival, proliferation, migration, and differentiation of cells. Studies have found alterations in specific growth factors in anorexia nervosa (AN).

METHODS

This systematic review and meta-analysis examined articles from three databases, measuring growth factors in AN cross-sectionally and longitudinally, and in recovered AN (rec-AN) cross-sectionally. Random-effects meta-analyses were conducted for brain-derived neurotrophic factor (BDNF) and insulin growth factor-I (IGF-1) for cross-sectional and longitudinal studies.

RESULTS

A total of 82 studies were included: 56 cross-sectional (BDNF: n = 15; IGF-1: n = 41) and 24 longitudinal (BDNF: n = 5; IGF-1: n = 19) were meta-analysed and 20 studies were narratively synthesised. In cross-sectional analyses, BDNF and IGF-1 were lower in AN compared to controls, and BDNF was marginally greater in rec-AN compared to controls. In longitudinal meta-analyses, BDNF and IGF-1 increased from baseline to follow-up. Cross-sectional subgroup analyses revealed no differences in BDNF between controls and AN binge-eating/purging subtypes.

CONCLUSIONS

It is likely that the low BDNF and IGF-1 levels found in AN are consequences of starvation, which are reversible with weight restoration. The increase in BDNF and IGF-1 during therapeutic weight restoration might improve neuroplasticity, which is the basis of learning, and thus psychotherapeutic success.

Skin microbiota analysis in patients with anorexia nervosa and healthy-weight controls reveals microbial indicators of healthy weight and associations with the antimicrobial peptide psoriasin

Anorexia nervosa (AN), a psychiatric condition defined by low body weight for age and height, is associated with numerous dermatological conditions. Yet, clinical observations report that patients with AN do not suffer from infectious skin diseases like those associated with primary malnutrition. Cell-mediated immunity appears to be amplified in AN; however, this proinflammatory state does not sufficiently explain the lower incidence of infections. Antimicrobial peptides (AMPs) are important components of the innate immune system protecting from pathogens and shaping the microbiota. In Drosophila melanogaster starvation precedes increased AMP gene expression. Here, we analyzed skin microbiota in patients with AN and age-matched, healthy-weight controls and investigated the influence of weight gain on microbial community structure. We then correlated features of the skin microbial community with psoriasin and RNase 7, two highly abundant AMPs in human skin, to clarify whether an association between AMPs and skin microbiota exists and whether such a relationship might contribute to the resistance to cutaneous infections observed in AN. We find significant statistical correlations between Shannon diversity and the highly abundant skin AMP psoriasin and bacterial load, respectively. Moreover, we reveal psoriasin significantly associates with Abiotrophia, an indicator for the healthy-weight control group. Additionally, we observe a significant correlation between an individual's body mass index and Lactobacillus, a microbial indicator of health. Future investigation may help clarify physiological mechanisms that link nutritional intake with skin physiology.

Effects of Different Types of Chronic Training on Bioenergetic Profile and Reactive Oxygen Species Production in LHCN-M2 Human Myoblast Cells

Human skeletal muscle contains three different types of fibers, each with a different metabolism. Exercise differently contributes to differentiation and metabolism in human myoblast cells. The aims of the present study were to investigate the effects of different types of chronic training on the human LHCN-M2 myoblast cell bioenergetic profile during differentiation in real time and on the ROS overproduction consequent to H₂O₂ injury. We demonstrated that exercise differently affects the myoblast bioenergetics: aerobic exercise induced the most efficient glycolytic and oxidative capacity and proton leak reduction compared to untrained or anaerobic trained sera-treated cells. Similarly, ROS overproduction after H₂O₂ stress was lower in cells treated with differently trained sera compared to untrained sera, indicating a cytoprotective effect of training on the reduction of oxidative stress, and thus the promotion of longevity. In conclusion, for the first time, this study has provided knowledge regarding the modifications induced by different types of chronic training on human myoblast cell bioenergetics during the differentiation process in real time, and on ROS overproduction due to stress, with positive implications in terms of longevity.

Expression of CXCR4 on CD4+ T cells predicts body composition parameters in female adolescents with anorexia nervosa

Anorexia nervosa (AN) is a severe eating disorder characterized by excessive weight loss and lack of recognition of the seriousness of the current low body weight. Individuals with AN frequently exhibit an enhanced inflammatory state and altered blood levels of cytokines and chemokines. However, the expression of chemokine receptors in AN and the association with body composition parameters and treatment effects are still unknown. In this study, we examined the expression of CCR4, CCR6, CXCR3, and CXCR4 on peripheral blood T cells in female adolescents with AN before (T0, n = 24) and after 6 weeks of multimodal therapy (T1, n = 20). We also investigated their value to predict body mass index (BMI) and fat mass index (FMI) at baseline. Using multi-parameter flow cytometry, we found increased expression of CCR4, CXCR3, and CXCR4, but not CCR6, on CD4⁺ T cells in AN at T0 when compared to healthy controls (HC, n = 20). At T1, CXCR3 and CXCR4 expression decreased in AN. We found a close link between CCR4, CCR6 and CXCR4 expression and the adolescent mental health status in the study cohort as determined by the Strengths and Difficulties Questionnaire (SDQ). Specifically, CXCR4 expression correlated positively with emotional symptoms and peer relationship problems, as well as with the total sum score of the SDQ. In addition, CXCR4 expression on CD4⁺ T cells was a significant predictor of BMI and FMI in female adolescents. Our findings that CXCR4 expression on T cells is altered in adolescents with AN and predicts body composition parameters in adolescents suggest an impact of this chemokine receptor in the pathogenesis of AN.

Adolescent eating disorder with catheter-related bloodstream infection

BACKGROUND

Treatment of adolescent eating disorder requires early improvement of nutritional status. Central venous hyperalimentation is used but catheter-related bloodstream infection (CRBSI) is a complication. There have been no reports examining risk factors for CRSBI in eating disorders.

METHODS

The subjects were 51 patients who received nutritional therapy with the use of a peripherally inserted central catheter (PICC) from January 2012 to December 2019. The courses of weight and white blood cell (WBC) count were examined retrospectively during nutritional therapy. Onset factors for CRBSI were determined and a case series of CRBSI caused by Candida parapsilosis is presented.

RESULTS

The day of minimum weight occurred on or before day 7 in 37 of the 51 patients, and this day was preceded by the day with the lowest WBC at a significant rate. The minimum weight day was significantly delayed in CRSBI cases compared with non-CRBSI cases (P = 0.02). In the case series of CRBSI caused by C. parapsilosis, the median WBC count before CRBSI decreased to 2,570 (1,680-3,270)/μL at a median of day (12-90) 36. Catheter-related bloodstream infection developed at a median of day (26-133) 38. The PICC was immediately removed and an antifungal drug was started, leading to cure with no after effects in all subjects.

CONCLUSIONS

In patients with an eating disorder treated with nutritional therapy using a PICC, prolonged resistance to weight gain became a risk factor for developing CRBSI. White blood cell counts recover after weight gain, which suggests that there is a risk of developing CRBSI, even with improved appetite and weight gain.

COVID-19 and the gastrointestinal tract: Source of infection or merely a target of the inflammatory process following SARS-CoV-2 infection?

Gastrointestinal (GI) symptoms have been described in a conspicuous percentage of coronavirus disease 2019 (COVID-19) patients. This clinical evidence is supported by the detection of viral RNA in stool, which also supports the hypothesis of a possible fecal-oral transmission route. The involvement of GI tract in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is corroborated by the theoretical assumption that angiotensin converting enzyme 2, which is a SARS-CoV-2 target receptor, is present along the GI tract. Studies have pointed out that gut dysbiosis may occur in COVID-19 patients, with a possible correlation with disease severity and with complications such as multisystem inflammatory syndrome in children. However, the question to be addressed is whether dysbiosis is a consequence or a contributing cause of SARS-CoV-2 infection. In such a scenario, pharmacological therapies aimed at decreasing GI permeability may be beneficial for COVID-19 patients. Considering the possibility of a fecal-oral transmission route, water and environmental sanitation play a crucial role for COVID-19 containment, especially in developing countries.

Fractalkine, sICAM-1 and Kynurenine Pathway in Restrictive Anorexia Nervosa-Exploratory Study

The link between the kynurenine pathway and immunomodulatory molecules—fractalkine and soluble intercellular adhesion molecule-1 (sICAM-1)—in anorexia nervosa (AN) remains unknown. Fractalkine, sICAM-1, tryptophan (TRP), kynurenine (KYN), neuroprotective kynurenic acid (KYNA), neurotoxic 3-OH-kynurenine (3-OH-KYN), and the expression of mRNA for kynurenine aminotransferases (KAT1-3) were studied in 20 female patients with restrictive AN (mostly drug-free, all during first episode of the disease) and in 24 controls. In AN, serum fractalkine, but not sICAM-1, KYNA, KYN, TRP or 3-OH-KYN, was higher; ratios TRP/KYN, KYN/KYNA, KYN/3-OH-KYN and KYNA/3-OH-KYN were unaltered. The expression of the gene encoding KAT3, but not of genes encoding KAT1 and KAT2 (measured in blood mononuclear cells), was higher in patients with AN. In AN, fractalkine positively correlated with TRP, while sICAM-1 was negatively associated with 3-OH-KYN and positively linked with the ratio KYN/3-OH-KYN. Furthermore, TRP and fractalkine were negatively associated with the body mass index (BMI) in AN. Expression of KAT1, KAT2 and KAT3 did not correlate with fractalkine, sICAM-1 or BMI, either in AN or control. Increased fractalkine may be an independent factor associated with the restrictive type of AN. Excessive physical activity probably underlies increased expression of KAT3 observed among enrolled patients. Further, longitudinal studies on a larger cohort of patients should be aimed to clarify the contribution of fractalkine and KAT3 to the pathogenesis of AN.

Anorexia Nervosa and the Immune System-A Narrative Review

The pathogenesis of an increasing number of chronic diseases is being attributed to effects of the immune system. However, its role in the development and maintenance of anorexia nervosa is seemingly under-appreciated. Yet, in examining the available research on the immune system and genetic studies in anorexia nervosa, one becomes increasingly suspicious of the immune system’s potential role in the pathophysiology of anorexia nervosa. Specifically, research is suggestive of increased levels of various pro-inflammatory cytokines as well as the spontaneous production of tumor necrosis factor in anorexia nervosa; genetic studies further support a dysregulated immune system in this disorder. Potential contributors to this dysregulated immune system are discussed including increased oxidative stress, chronic physiological/psychological stress, changes in the intestinal microbiota, and an abnormal bone marrow microenvironment, all of which are present in anorexia nervosa.

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.

Reconceptualizing anorexia nervosa

Anorexia nervosa (AN) has one of the highest mortality rates of any psychiatric disorder. Treatments are often ineffective and relapse is common. Most research attempting to understand the underlying causes and maintenance factors of AN has focused on environmental contributions, yet there is much to be explored in terms of biological risk and maintenance factors. In this paper, we focus primarily on AN research related to genetics and the complex microbial community in the gut (intestinal microbiota), and how these impact our conceptualization of this disorder. Emerging research identifying significant negative genetic correlations between AN and obesity suggests that the conditions may represent 'metabolic bookends'. The identification of underlying biological mechanisms may provide both insight into extreme weight dysregulation on both ends of the spectrum and new possible points of entry for AN treatment. Additionally, the reported microbial imbalance (dysbiosis) in the gut microbiota in AN patients, potentially due to a nutrient- and energy-deprived gut environment, implies alterations in functional and metabolic capacity of the gut microbiome. The extent to which AN and obesity can also be considered to be 'microbiome bookends' requires further investigation. Finally, we discuss ongoing and future AN projects exploring the interplay between host genomics, the environment, and cumulative microbial genomes (microbiome) as well as interventions at the microbial and gut level.

Brain-Behavior-Immune Interaction: Serum Cytokines and Growth Factors in Patients with Eating Disorders at Extremes of the Body Mass Index (BMI) Spectrum

Alterations of the immune system are known in eating disorders (EDs), however the importance of cytokine balance in this context has not been clarified. We compared cytokines and growth factors at opposite ends of BMI ranges, in 90 patients classified in relation to BMI, depressive and EDs comorbidities. Serum concentrations of interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) were determined by a biochip analyzer (Randox Labs). Differences were calculated through ANOVA. Possible predictors of higher cytokine levels were evaluated through regression analysis. IL-1α, IL-10, EGF, and IFN-γ were altered individuals with anorexia nervosa (AN) and binge eating disorder (BED). Night-eating was associated with IL-8 and EGF levels, IL-10 concentrations with post-dinner eating and negatively with sweet-eating, long fasting with higher IFN-γ levels. IL-2 increase was not linked to EDs, but to the interaction of depression and BMI. Altogether, for the first time, IL-1α, IL-10, EGF, and IFN-γ were shown to differ between AN and HCs, and between AN and individuals with obesity with or without BED. Only IL-2 was influenced by depression. Dysfunctional eating behaviors predicted abnormal concentrations of IL-10, EGF, IL-8 and IFN-γ.

Increased lipid and lipoprotein concentrations in anorexia nervosa: A systematic review and meta-analysis

OBJECTIVE

Alterations in blood lipid concentrations in anorexia nervosa (AN) have been reported; however, the extent, mechanism, and normalization with weight restoration remain unknown. We conducted a systematic review and a meta-analysis to evaluate changes in lipid concentrations in acutely-ill AN patients compared with healthy controls (HC) and to examine the effect of partial weight restoration.

METHOD

A systematic literature review and meta-analysis (PROSPERO: CRD42017078014) were conducted for original peer-reviewed articles.

RESULTS

Forty-eight studies were eligible for review; 33 for meta-analyses calculating mean differences (MD). Total cholesterol (MD = 22.7 mg/dL, 95% CI = 12.5, 33.0), high-density lipoprotein (HDL; MD = 3.4 mg/dL, CI = 0.3, 7.0), low-density lipoprotein (LDL; MD = 12.2 mg/dL, CI = 4.4, 20.1), triglycerides (TG; MD = 8.1 mg/dL, CI = 1.7, 14.5), and apolipoprotein B (Apo B; MD = 11.8 mg/dL, CI = 2.3, 21.2) were significantly higher in acutely-ill AN than HC. Partially weight-restored AN patients had higher total cholesterol (MD = 14.8 mg/dL, CI = 2.1, 27.5) and LDL (MD = 16.1 mg/dL, CI = 2.3, 30.0). Pre- versus post-weight restoration differences in lipid concentrations did not differ significantly.

DISCUSSION

We report aggregate evidence for elevated lipid concentrations in acutely-ill AN patients compared with HC, some of which persist after partial weight restoration. This could signal an underlying adaptation or dysregulation not fully reversed by weight restoration. Although concentrations differed between AN and HC, most lipid concentrations remained within the reference range and meta-analyses were limited by the number of available studies.

Inflammatory Markers in Anorexia Nervosa: An Exploratory Study

Inflammation has been suggested to play a pathophysiological role in anorexia nervosa (AN). In this exploratory cross-sectional study, we measured serum concentrations of 40 inflammatory markers (including cytokines, chemokines, and adhesion molecules) and brain-derived neurotrophic factor (BDNF) in people with AN (n = 27) and healthy controls (HCs) (n = 13). Many of these inflammatory markers had not been previously quantified in people with AN. Eating disorder (ED) and general psychopathology symptoms were assessed. Body mass index (BMI) and body composition data were obtained. Interleukin (IL)-6, IL-15, and vascular cell adhesion molecule (VCAM)-1 concentrations were significantly elevated and concentrations of BDNF, tumor necrosis factor (TNF)-β, and vascular endothelial growth factor (VEGF)-A were significantly lower in AN participants compared to HCs. Age, BMI, and percentage body fat mass were identified as potential confounding variables for several of these inflammatory markers. Of particular interest is that most of the quantified markers were unchanged in people with AN, despite them being severely underweight with evident body fat loss, and having clinically significant ED symptoms and severe depression and anxiety symptoms. Future research should examine the replicability of our findings and consider the effect of additional potential confounding variables, such as smoking and physical activity, on the relationship between AN and inflammation.

Study of salivary and serum vaspin and total antioxidants in anorexia nervosa

OBJECTIVES

Patients with anorexia nervosa (AN) are primarily at high risk of multiple somatic complications, including oral diseases. In recent years, a number of new molecules that may play a potentially important role in AN progress and prognosis have been identified in saliva, but their exact roles are still poorly understood. Two such group of substances are antioxidants and vaspin. The purpose of this observational, cross-sectional study was to measure both the salivary and serum total antioxidant status (TAS), and vaspin (VASP) concentrations of patients with AN in comparison to an average population.

MATERIAL AND METHODS

Ninety subjects participated (30 patients with AN, 60 matched healthy control subjects). A clinical examination was made, and blood and salivary samples were taken during the acute stage of AN (BMI < 15 kg/m²) in the first week of hospitalization. Enzyme immunoassay (ELISA) suitable for measuring VASP and colorimetric assay for TAS were used.

RESULTS

Anorexic patients had significant reductions in salivary flow, TAS, and an elevation in VASP levels in their saliva and serum. Significant correlations between TAS, VASP, salivary flow, and nutritional status were detected.

CONCLUSION

Determination of TAS and VASP in combined biological material confirmed that saliva might be a reliable non-invasive source of information for potent nutritional biomarkers.

CLINICAL RELEVANCE

Our findings suggest that VASP cannot be excluded, as its increased concentration in saliva is an adaptive mechanism in reduced TAS, one resulting from diminished salivary secretion. It is therefore worth conducting further research aimed at recognizing the role of TAS and VASP in the saliva of underweight patients.

Anorexia nervosa and uric acid beyond gout: An idea worth researching

Uric acid is best known for its role in gout-the most prevalent inflammatory arthritis in humans-that is also described as an unusual complication of anorexia nervosa (AN). However, beyond gout, uric acid could also be involved in the pathophysiology and psychopathology of AN, as it has many biological functions serving as a pro- and antioxidant, neuroprotector, neurostimulant, and activator of the immune response. Further, recent research suggests that uric acid could be a biomarker of mood dysfunction, personality traits, and behavioral patterns. This article discusses the hypothesis that uric acid in AN may not be a mere innocent bystander determined solely by AN behavior and its medical complications. In contrast, the relation between uric acid and AN may have evolutionary origin and may be reciprocal, where uric acid regulates some features and pathophysiological processes of AN, including weight and metabolism regulation, oxidative stress, immunity, mood, cognition, and (hyper)activity.

Studies of Isolated Peripheral Blood Cells as a Model of Immune Dysfunction

Peripheral blood mononuclear cells (PBMCs) have been used as a surrogate model of immune function in studies of multiple medical areas, such as metabolic diseases and immune dysfunction. This chapter describes a standardized technique for blood draw and preparation of PBMCs from whole blood using density gradient centrifugation, followed by cell culture. The main focus is on collection of the PBMC culture media and extraction of cellular proteins in order to provide the materials for biomarker studies.

Inverse Association of Circulating SIRT1 and Adiposity: A Study on Underweight, Normal Weight, and Obese Patients

Context: Sirtuins (SIRTs) are NAD+-dependent deacetylases, cellular sensors to detect energy availability, and modulate metabolic processes. SIRT1, the most studied family member, influences a number of tissues including adipose tissue. Expression and activity of SIRT1 reduce with weight gain and increase in conditions of starvation. Objective: To focus on SIRT1 plasma concentrations in different conditions of adiposity and to correlate SIRT1 with fat content and distribution, energy homeostasis and inflammation in under-weight, normal-weight, and obese individuals. Materials and Methods: 21 patients with anorexia nervosa, 26 normal-weight and 75 patients with obesity were evaluated. Body fat composition by dual-energy X-ray absorptiometry, ultrasound liver adiposity, echocardiographic epicardial fat thickness (EFT), inflammatory (ESR, CRP, and fibrinogen), and metabolic (FPG, insulin, LDL- and HDL-cholesterol, triglycerides) parameters, calculated basal metabolic rate (BMR) and plasma SIRT1 (ELISA) were measured. Results: SIRT1 was significantly higher in anorexic patients compared to normal-weight and obese patients (3.27 ± 2.98, 2.27 ± 1.13, and 1.36 ± 1.31 ng/ml, respectively). Linear regression models for each predictor variable adjusted for age and sex showed that SIRT1 concentration was inversely and significantly correlated with EFT, fat mass %, liver fat content, BMR, weight, BMI, WC, LDL-cholesterol, insulin, ESR. Stepwise multiple regression analysis revealed that age and EFT were the best independent correlates of SIRT1 (β = -0.026 ± 0.011, p = 0.025, and β = -0.516 ± 0.083, p < 0.001, respectively). Conclusions: Plasma SIRT1 shows a continuous pattern that inversely follows the whole spectrum of adiposity. SIRT1 significantly associates with EFT, a strong index of visceral fat phenotype, better than other indexes of adiposity studied here.

Immune disorders in anorexia

Anorexia nervosa is a disease involving eating disorders. It mainly affects young people, especially teenage women. The disease is often latent and occurs in many sub-clinical and partial forms. Approximately from 0.3% to 1% of the population suffers from anorexia. It has been shown that patients with anorexia develop neurotransmitter-related disorders, leading to uncontrolled changes in the immune and endocrine systems. Interactions between cytokines, neuropeptides, and neurotransmitters play an important role in disease development. Significant malnutrition induces disorders and alterations in T-cell populations. The cellular response in patients with anorexia nervosa has been shown to be normal, although opinions on this issue are controversial. Laboratory studies on neutrophils in anorexia patients showed decreased adhesion and reduced bactericidal and cell activities. Despite such unfavourable results, patients with anorexia are resistant to infections, which are very rare in this group. Glutamine improves the performance of the human immune system. The administration of glutamine to anorexia patients, as a supplement to parenteral nutrition, has resulted in significant improvements in immune system parameters. The results of previous studies on the causes and risk factors in the development of anorexia nervosa are still ambiguous. One can hope that the differences and similarities between patients with anorexia nervosa and those with other forms of protein-calorie malnutrition may be helpful in determining the relationship between nutritional status and body defences and susceptibility to infection, and can help to broaden the knowledge about the aetiopathogenesis of anorexia nervosa.

Cellular bioenergetics is impaired in patients with chronic fatigue syndrome

Chronic fatigue syndrome (CFS) is a highly debilitating disease of unknown aetiology. Abnormalities in bioenergetic function have been cited as one possible cause for CFS. Preliminary studies were performed to investigate cellular bioenergetic abnormalities in CFS patients. A series of assays were conducted using peripheral blood mononuclear cells (PBMCs) from CFS patients and healthy controls. These experiments investigated cellular patterns in oxidative phosphorylation (OXPHOS) and glycolysis. Results showed consistently lower measures of OXPHOS parameters in PBMCs taken from CFS patients compared with healthy controls. Seven key parameters of OXPHOS were calculated: basal respiration, ATP production, proton leak, maximal respiration, reserve capacity, non-mitochondrial respiration, and coupling efficiency. While many of the parameters differed between the CFS and control cohorts, maximal respiration was determined to be the key parameter in mitochondrial function to differ between CFS and control PBMCs due to the consistency of its impairment in CFS patients found throughout the study (p≤0.003). The lower maximal respiration in CFS PBMCs suggests that when the cells experience physiological stress they are less able to elevate their respiration rate to compensate for the increase in stress and are unable to fulfil cellular energy demands. The metabolic differences discovered highlight the inability of CFS patient PBMCs to fulfil cellular energetic demands both under basal conditions and when mitochondria are stressed during periods of high metabolic demand.

Increased naive CD4+ and B lymphocyte subsets are associated with body mass loss and drive relative lymphocytosis in anorexia nervosa patients

Anorexia nervosa (AN) is an atypical form of malnutrition with peculiar changes in the immune system. We hypothesized that different lymphocyte subsets are differentially affected by malnutrition in AN, and thus, our aim was to investigate the influence of body mass loss on the variability of lymphocyte subsets in AN patients. A group of 66 adolescent female patients, aged 12-17 years, referred for their first episode of either AN or feeding or eating disorders not elsewhere classified were studied upon admission (46 AN-restricting subtype, 11 AN-binge/purging subtype, and 9 feeding or eating disorders not elsewhere classified). Ninety healthy adolescents served as controls. White blood cells and lymphocyte subsets were analyzed by flow cytometry. Relationships with the body mass index (BMI) z score were assessed in linear models adjusted by diagnostic subtype and age. Leukocyte numbers were lower in AN patients than in controls, and relative lymphocytosis was observed in AN-restricting subtype. Lower CD8⁺, NK, and memory CD8⁺ counts were found in eating disorder patients compared with controls. No differences were found for CD4⁺ counts or naive and memory CD4⁺ subsets between the groups. Negative associations between lymphocyte percentage and the BMI z score, as well as between the B cell counts, naive CD4⁺ percentage and counts, and the BMI z score, were found. In conclusion, increased naive CD4⁺ and B lymphocyte subsets associated with body mass loss drive the relative lymphocytosis observed in AN patients, which reflects an adaptive mechanism to preserve the adaptive immune response.

TRPM8 downregulation by angiotensin II in vascular smooth muscle cells is involved in hypertension

Angiotensin II (Ang II)-induced injury of vascular smooth muscle cells (VSMCs) serves an important role in hypertension and other cardiovascular disorders. Transient receptor potential melastatin 8 (TRPM8) is a thermally‑regulated Ca2+‑permeable channel that is activated by reduced body temperature. Although several recent studies have revealed the regulatory effect of TRPM8 in vascular tone and hypertension, the precise role of TRPM8 in dysfunction of vascular smooth muscle cells (VSMCs) induced by Ang II remains elusive. In the present study, the possible function of TRPM8 in Ang II‑induced VSMCs malfunction in vivo and in vitro was investigated. In the aortae from rats that had undergone a two‑kidney one‑clip operation, which is a widely‑used renovascular hypertension model, the mRNA and protein levels of TRPM8 were reduced. In addition, exogenous Ang II treatment decreased TRPM8 mRNA and protein expression levels in primary cultures of rat VSMCs. TRPM8 activation by menthol, a pharmacological agonist, in VSMCs, significantly attenuated the Ang II‑induced increase in reactive oxygen species and H2O2 production. In addition, TRPM8 activation reduced the Ang II‑induced upregulation of NADPH oxidase (NOX) 1 and NOX4 in VSMCs. Furthermore, TRPM8 activation relieved the Ang II‑induced activation of ras homolog gene family, member A‑rho associated protein kinase 2 and janus kinase 2 signaling pathways in VSMCs. In conclusion, the results presented in the current study indicated that TRPM8 downregulation by Ang II in VSMCs may be involved in hypertension.

Temporal Association of Certain Neuropsychiatric Disorders Following Vaccination of Children and Adolescents: A Pilot Case-Control Study

BACKGROUND

Although the association of the measles, mumps, and rubella vaccine with autism spectrum disorder has been convincingly disproven, the onset of certain brain-related autoimmune and inflammatory disorders has been found to be temporally associated with the antecedent administration of various vaccines. This study examines whether antecedent vaccinations are associated with increased incidence of obsessive-compulsive disorder (OCD), anorexia nervosa (AN), anxiety disorder, chronic tic disorder, attention deficit hyperactivity disorder, major depressive disorder, and bipolar disorder in a national sample of privately insured children.

METHODS

Using claims data, we compared the prior year's occurrence of vaccinations in children and adolescents aged 6-15 years with the above neuropsychiatric disorders that were newly diagnosed between January 2002 and December 2007, as well as two control conditions, broken bones and open wounds. Subjects were matched with controls according to age, gender, geographical area, and seasonality. Conditional logistic regression models were used to determine the association of prior vaccinations with each condition.

RESULTS

Subjects with newly diagnosed AN were more likely than controls to have had any vaccination in the previous 3 months [hazard ratio (HR) 1.80, 95% confidence interval 1.21-2.68]. Influenza vaccinations during the prior 3, 6, and 12 months were also associated with incident diagnoses of AN, OCD, and an anxiety disorder. Several other associations were also significant with HRs greater than 1.40 (hepatitis A with OCD and AN; hepatitis B with AN; and meningitis with AN and chronic tic disorder).

CONCLUSION

This pilot epidemiologic analysis implies that the onset of some neuropsychiatric disorders may be temporally related to prior vaccinations in a subset of individuals. These findings warrant further investigation, but do not prove a causal role of antecedent infections or vaccinations in the pathoetiology of these conditions. Given the modest magnitude of these findings in contrast to the clear public health benefits of the timely administration of vaccines in preventing mortality and morbidity in childhood infectious diseases, we encourage families to maintain vaccination schedules according to CDC guidelines.

Near-fatal Anorexia Nervosa in a Middle-aged Woman

Anorexia nervosa (AN) is a serious psychiatric disorder which typically occurs in young women; however, more and more cases in middle-aged women are being reported. The management of this complex disease requires a team approach, and full recovery occurs only in 50% of patients. Endocrine and metabolic complications are commonly observed, the latter of which may even be life-threatening, and require prompt and proper management. Infections, albeit reported, are not usually a major clinical problem in these patients. We herein report the case of a severely malnourished middle-aged woman with long-standing AN who was hospitalized with marked hypokalaemia (1.5 mEq/L) and rhabdomyolysis; during hospitalization she developed septic shock and acute respiratory distress syndrome, which required urgent admission to the intensive care unit. She underwent sedation and tracheal intubation for mechanical ventilation and was managed with combined therapies, which eventually led to a successful outcome. Life-threatening medical complications can occur not only in young women but in middle-aged women with AN as well and require a combined multidisciplinary approach.

Prevailing vitamin D status influences mitochondrial and glycolytic bioenergetics in peripheral blood mononuclear cells obtained from adults

BACKGROUND

Circulating peripheral blood mononuclear cells (PBMCs) are exposed to metabolic and immunological stimuli that influence their functionality. We hypothesized that prevailing vitamin D status [25(OH)D] would modulate the bioenergetic profile of PBMCs derived from humans.

MATERIALS AND METHODS

38 participants (16 males, 22 females) ranging in body fat from 14-51% were studied. PBMCs were isolated from whole blood, counted and freshly seeded for bioenergetic analysis using the Seahorse XF^e96 flux analyser. Whole body energy metabolism via indirect calorimetry, body composition by dual-energy X-ray absorptiometry, and relevant clinical biochemistry were measured. Data was analysed based on 25(OH)D cut-offs of <50nmol/L (Group 1, n=12), 50-75nmol/L (Group 2, n=15) and ≥75nmol/L (Group 3, n=11). A multivariate general linear model adjusting for age, fat mass, fat-free mass, parathyroid hormone and insulin sensitivity was used.

RESULTS

There were significant differences in cellular mitochondrial function between groups. Group 1 had significantly higher basal respiration (p=0.001), non-mitochondrial respiration (p=0.009), ATP production (p=0.001), proton leak (p=0.018), background glycolysis (p=0.023) and glycolytic reserve (p=0.039) relative to either Group 2 or Group 3; the latter two did not differ on any measures. There were no differences in bioenergetic health index (BHI), resting metabolic rates and systemic inflammatory markers between groups.

CONCLUSIONS

Inadequate vitamin D status adversely influenced bioenergetic parameters of PBMCs obtained from adults, in a pattern consistent with increased oxidative metabolism and activation of these cells.

Towards a science of eating disorders: Replacing myths with realities: The fourth Birgit Olsson lecture

BACKGROUND

For too long we have been "stuck" in old perspectives that have hampered the advance of knowledge. In part, this is related to the challenges that people have in unlearning misinformation.

AIM

To address the need for an upgrade in the eating disorders field.

METHOD

To assist with replacing outdated and inaccurate ideas with new data, this lecture reviewed novel approaches to eating disorders that engage scientists and clinicians from diverse fields to approach questions about aetiology and treatment of eating disorders through new lenses. This forward-looking lecture outlined critical questions that need to be addressed to move the field forward and strategies for engaging scientists from different fields.

RESULTS

Leading-edge findings on genetics, intestinal microbiota, and neuroscience are reviewed.

CONCLUSIONS

This review encourages the integration of new evidence-based knowledge to form the backbone of our understanding of and approach to eating disorders.

Peripheral blood natural killer cells and mild thyroid abnormalities in women with reproductive failure

Abnormalities in peripheral blood natural killer (NK) cells have been reported in women with primary infertility and recurrent spontaneous abortion (RSA) and several studies have been presented to define cutoff values for abnormal peripheral blood NK cell levels in this context. Elevated levels of NK cells were observed in infertile/RSA women in the presence of thyroid autoimmunity (TAI), while no studies have been carried out, to date, on NK cells in infertile/RSA women with non-autoimmune thyroid diseases. The contribution of this study is two-fold: (1) the evaluation of peripheral blood NK cell levels in a cohort of infertile/RSA women, in order to confirm related data from the literature; and (2) the assessment of NK cell levels in the presence of both TAI and subclinical hypothyroidism (SCH) in order to explore the possibility that the association between NK cells and thyroid function is not only restricted to TAI but also to SCH. In a retrospective study, 259 age-matched women (primary infertility [n = 49], primary RSA [n = 145], and secondary RSA [n = 65]) were evaluated for CD56+CD16+NK cells by flow cytometry. Women were stratified according to thyroid status: TAI, SCH, and without thyroid diseases (ET). Fertile women (n = 45) were used as controls. Infertile/RSA women showed higher mean NK cell levels than controls. The cutoff value determining the abnormal NK cell levels resulted ⩾15% in all the groups of women. Among the infertile/RSA women, SCH resulted the most frequently associated thyroid disorder while no difference resulted in the prevalence of TAI and ET women between patients and controls. A higher prevalence of women with NK cell levels ⩾15% was observed in infertile/RSA women with SCH when compared to TAI/ET women. According to our data, NK cell assessment could be used as a diagnostic tool in women with reproductive failure and we suggest that the possible association between NK cell levels and thyroid function can be described not only in the presence of TAI but also in the presence of non-autoimmune thyroid disorders.