The impact of body mass index on adaptive immune cells in the human bone marrow

Serum copper and obesity among healthy adults in the National Health and Nutrition Examination Survey

BACKGROUND

Copper (Cu) homeostasis are important processes in the cause of metabolic diseases, but the association between Cu and obesity remains unclear.

METHODS

Participants were drawn from the 2011-2016 National Health and Nutrition Examination Survey (NHANES). Weighted logistic regression assessed the associations of serum Cu concentrations (tertiles) with obesity and central obesity in individuals without comorbidities. Obesity was defined as a BMI ≥30.0 kg/m2, and central obesity was defined as a waist circumference ≥80 cm for women and ≥95 cm for men.

RESULTS

This cross-sectional study included 1,665 adults without comorbidities, representing 24,744,034 people (mean age 35.1 years, 48.5% female). High serum Cu levels (tertile 3: ≥19.19 μmol/L) were associated with higher odds of obesity (adjusted odds ratio [OR]: 4.48, 95% CI[confidence interval]: 2.44-8.32) and central obesity (OR: 2.36, 95% CI: 1.19-4.66) compared to low serum Cu levels (tertile 1: ≤15.64 μmol/L). The dose-response curve showed a nonlinear association between Cu levels and obesity (P-nonlinear = 0.02) and a linear association with central obesity (P-nonlinear = 0.21).

CONCLUSION

This study suggests that higher serum Cu levels are associated with increased odds of obesity in healthy American adults.

Immune Cell Alterations in Psychotic Disorders: A Comprehensive Systematic Review and Meta-Analysis

BACKGROUND

A comprehensive meta-analysis on the composition of circulating immune cells from both the myeloid and the lymphoid lines including specialized subsets in blood and cerebrospinal fluid (CSF) of patients with psychotic disorders compared with healthy control participants has been lacking.

METHODS

Multiple databases (PubMed, EMBASE, Cochrane Library, Web of Science, ClinicalTrials.gov, and PsycINFO) were searched for eligible studies up until October 18, 2022. All studies investigating circulating immune cells in the blood and CSF from patients with psychotic disorders (ICD-10: F20 and F22-29) compared with healthy control participants were included.

RESULTS

A total of 86 studies were included in the meta-analysis. In the blood, the following categories of immune cells were elevated: leukocyte count (31 studies, standardized mean difference [SMD] = 0.35; 95% CI, 0.24 to 0.46), granulocyte count (4 studies, SMD = 0.57; 95% CI, 0.12 to 1.01), neutrophil granulocyte count (21 studies, SMD = 0.32; 95% CI, 0.11 to 0.54), monocyte count (23 studies, SMD = 0.40; 95% CI, 0.23 to 0.56), and B lymphocyte count (10 studies, SMD = 0.26; 95% CI, 0.04 to 0.48). Additionally, the neutrophil/lymphocyte ratio (23 studies, SMD = 0.40; 95% CI, 0.19 to 0.60), the monocyte/lymphocyte ratio (9 studies, SMD = 0.31; 95% CI, 0.04 to 0.57), and the platelet/lymphocyte ratio (10 studies, SMD = 0.23; 95% CI, 0.03 to 0.43) were elevated. The CSF cell count showed a similar tendency but was not significantly elevated (3 studies, SMD = 0.14; 95% CI, -0.04 to 0.32).

CONCLUSIONS

The results indicate a broad activation of the immune system in psychotic disorders, with cells from both the myeloid and the lymphoid line being elevated. However, CSF analyses were lacking in most of the studies, and many studies were hampered by insufficient adjustment for confounding factors such as body mass index and smoking.

The Impact of Obesity on T and NK Cells after LVAD Implantation

INTRODUCTION

Infections are a major problem after left ventricular assist device (LVAD) implantation that affects morbidity, mortality, and the quality of life. Obesity often increases the risk for infection. In the cohort of LVAD patients, it is unknown if obesity affects the immunological parameters involved in viral defense. Therefore, this study investigated whether overweight or obesity affects immunological parameters such as CD8+ T cells and natural killer (NK) cells.

METHODS

Immune cell subsets of CD8+ T cells and NK cells were compared between normal-weight (BMI 18.5-24.9 kg/m2, n = 17), pre-obese (BMI 25.0-29.9 kg/m2, n = 24), and obese (BMI ≥30 kg/m2, n = 27) patients. Cell subsets and cytokine serum levels were quantified prior to LVAD implantation and at 3, 6, and 12 months after LVAD implantation.

RESULTS

At the end of the first postoperative year, obese patients (31.8% ± 2.1%) had a lower proportion of CD8+ T cells than normal-weight patients (42.4% ± 4.1%; p = 0.04), and the percentage of CD8+ T cells was negatively correlated with BMI (p = 0.03; r = -0.329). The proportion of circulating NK cells increased after LVAD implantation patients in normal-weight (p = 0.01) and obese patients (p < 0.01). Patients with pre-obesity showed a delayed increase (p < 0.01) 12 months after LVAD implantation. Further, obese patients showed an increase in the percentage of CD57+ NK cells after 6 and 12 months (p = 0.01) of treatment, higher proportions of CD56bright NK cells (p = 0.01), and lower proportions of CD56dim/neg NK cells (p = 0.03) 3 months after LVAD implantation than normal-weight patients. The proportion of CD56bright NK cells positively correlated with BMI (p < 0.01, r = 0.403) 1 year after LVAD implantation.

CONCLUSIONS

This study documented that obesity affects CD8+ T cells and subsets of NK cells in patients with LVAD in the first year after LVAD implantation. Lower proportions of CD8+ T cells and CD56dim/neg NK cells and higher proportion of CD56bright NK cells were detected in obese but not in pre-obese and normal-weight LVAD patients during the first year after LVAD implantation. The induced immunological imbalance and phenotypic changes of T and NK cells may influence viral and bacterial immunoreactivity.

Inflammaging: The ground for sarcopenia?

Sarcopenia is a progressive skeletal muscle disease that occurs most commonly in the elderly population, contributing to increased costs and hospitalization. Exercise and nutritional therapy have been proven to be effective for sarcopenia, and some drugs can also alleviate declines in muscle mass and function due to sarcopenia. However, there is no specific pharmacological treatment for sarcopenia at present. This review will mainly discuss the relationship between inflammaging and sarcopenia. The increased secretion of proinflammatory cytokines with aging may be because of cellular senescence, immunosenescence, alterations in adipose tissue, damage-associated molecular patterns (DAMPs), and gut microbes due to aging. These sources of inflammaging can impact the sarcopenia process through direct or indirect pathways. Conversely, sarcopenia can also aggravate the process of inflammaging, creating a vicious cycle. Targeting sources of inflammaging can influence muscle function, which could be considered a therapeutic target for sarcopenia. Moreover, not only proinflammatory cytokines but also anti-inflammatory cytokines can influence muscle and inflammation and participate in the progression of sarcopenia. This review focuses on the effects of TNF-α, IL-6, and IL-10, which can be detected in plasma. Therefore, clearing chronic inflammation by targeting proinflammatory cytokines (TNF-α, IL-1, IL-6) and the inflammatory pathway (JAK/STAT, autophagy, NF-κB) may be effective in treating sarcopenia.

Pediatric Obesity-Related Asthma: The Role of Nutrition and Nutrients in Prevention and Treatment

Childhood obesity rates have dramatically risen in numerous countries worldwide. Obesity is likely a factor in increased asthma risk, which is already one of the most widespread chronic respiratory pathologies. The pathogenic mechanism of asthma risk has still not yet been fully elucidated. Moreover, the role of obesity-related inflammation and pulmonary overreaction to environmental triggers, which ultimately result in asthma-like symptoms, and the importance of dietary characteristics is well recognized. Diet is an important adjustable element in the asthma development. Food-specific composition of the diet, in particular fat, sugar, and low-quality nutrients, is likely to promote the chronic inflammatory state seen in asthmatic patients with obesity. An unbalanced diet or supplementation as a way to control asthma more efficiently has been described. A personalized dietary intervention may improve respiratory symptoms and signs and therapeutic response. In this narrative review, we presented and discussed more recent literature on asthma associated with obesity among children, focusing on the risk of asthma among children with obesity, asthma as a result of obesity focusing on the role of adipose tissue as a mediator of systemic and local airway inflammation implicated in asthma regulation, and the impact of nutrition and nutrients in the development and treatment of asthma. Appropriate early nutritional intervention could possibly be critical in preventing and managing asthma associated with obesity among children.

Adipose Tissue Immunomodulation and Treg/Th17 Imbalance in the Impaired Glucose Metabolism of Children with Obesity

In the last few decades, obesity has increased dramatically in pediatric patients. Obesity is a chronic disease correlated with systemic inflammation, characterized by the presence of CD4 and CD8 T cell infiltration and modified immune response, which contributes to the development of obesity related diseases and metabolic disorders, including impaired glucose metabolism. In particular, Treg and Th17 cells are dynamically balanced under healthy conditions, but imbalance occurs in inflammatory and pathological states, such as obesity. Some studies demonstrated that peripheral Treg and Th17 cells exhibit increased imbalance with worsening of glucose metabolic dysfunction, already in children with obesity. In this review, we considered the role of adipose tissue immunomodulation and the potential role played by Treg/T17 imbalance on the impaired glucose metabolism in pediatric obesity. In the patient care, immune monitoring could play an important role to define preventive strategies of pediatric metabolic disease treatments.

Involvement of Interleukin-1 Receptor-Associated Kinase 4 and Interferon Regulatory Factor 5 in the Immunopathogenesis of SARS-CoV-2 Infection: Implications for the Treatment of COVID-19

Interleukin-1 receptor-associated kinase 4 (IRAK4) and interferon regulatory factor 5 (IRF5) lie sequentially on a signaling pathway activated by ligands of the IL-1 receptor and/or multiple TLRs located either on plasma or endosomal membranes. Activated IRF5, in conjunction with other synergistic transcription factors, notably NF-κB, is crucially required for the production of proinflammatory cytokines in the innate immune response to microbial infection. The IRAK4-IRF5 axis could therefore have a major role in the induction of the signature cytokines and chemokines of the hyperinflammatory state associated with severe morbidity and mortality in COVID-19. Here a case is made for considering IRAK4 or IRF5 inhibitors as potential therapies for the "cytokine storm" of COVID-19.

Obesity, Nutrients and the Immune System in the Era of COVID-19

The past year has shown that obesity is a risk factor for severe complications of SARS-CoV-2 infection. Excess fat mass during obesity is known to be a risk factor for chronic diseases but also for severe infections and infectious complications. We have focused here on the elements responsible for this particular susceptibility to infections and more specifically to COVID-19. Excess fat is, in itself, responsible for alterations of the immune system by disrupting the production and function of immune cells. Indeed, hypertrophic adipocytes produce more pro-inflammatory adipokines (including cytokines). The increase in their apoptosis induces a release of pro-inflammatory compounds into the circulation and a recruitment of pro-inflammatory macrophages into the adipose tissue. A chronic systemic inflammatory state is then observed. In addition, diet, apart from its role in the development of adipose tissue, can also affect the immune system, with excess simple sugars and saturated fats exerting pro-inflammatory effects. This inflammation, the adipokines released by the adipocytes, and the infiltration of lipids into the lymphoid organs affects the production of immune cells and, directly, the functions of these cells. The alteration of the immune system increases the risk of infection as well as complications, including secondary bacterial infections and septic states, and increases infection-related mortality. During COVID-19, the chronic inflammatory state promotes the cytokine shock, characteristic of severe forms, caused in particular by excessive activation of the NLRP3 inflammasome. Furthermore, in obese subjects, the already present endothelial dysfunction will render endothelial inflammation (endotheliitis) due to viral infiltration all the more severe. Added to this is a state of hypercoagulability and a decrease in respiratory capacity, leading to a risk of severe COVID-19 with cardiovascular complications, acute respiratory distress syndrome, and disseminated intravascular coagulation, which can lead to multiple organ failure and even death.

T cell phenotypes associated with insulin resistance: results from the Berlin Aging Study II

Background

Obesity is associated with chronic low-grade inflammation leading to metabolic and cardiovascular diseases, but a subset of obese individuals is considered insulin sensitive (IS). The underlying pathophysiologic mechanisms remain elusive and clinical studies on the relationship between inflammatory markers and metabolically healthy obesity (MHO) are scarce.

Methods

In this cross-sectional analysis, we included a sample of 437 older participants (60–84 years) from the Berlin Aging Study II (BASE-II). Peripheral blood mononuclear cells were isolated, immune cell subsets were analyzed with multiparameter flow cytometry and systemic cytokine levels were measured. Immune cell parameters were correlated with metabolic measures and multiple linear regression analysis was conducted and adjusted for various demographic and clinical factors.

Results

We found that frequencies of naïve and memory CD4⁺ and CD8⁺ T cells inversely correlated with measures for insulin sensitivity in the older population. Moreover, the percentages of naïve CD4⁺ and CD8⁺ T cells were significantly higher, whereas activated T cells and IL-6 levels were lower in IS compared to insulin resistant (IR) obese individuals. The percentages of naïve CD4⁺ and CD8⁺ T cells were predictive for impaired insulin sensitivity (ß = 0.16, p = 0.01 and ß = 0.11, p = 0.04), and the association of naïve CD4⁺ T cells with insulin sensitivity persisted after multivariate adjustment (ß = 0.14, p = 0.02).

Conclusions

These findings support the hypothesis that parameters of systemic inflammation can differentiate IS from IR obese individuals that are at higher risk for cardiometabolic diseases and may have clinical implications with regard to obesity treatment stratification.

Trial registration

DRKS00009277. Registered 31 August 2015 - Retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12979-020-00211-y.