Influence of obesity on immune function

Deep immune cell phenotyping and induced immune cell responses at admission stratified by BMI in patients hospitalized with COVID-19: An observational multicenter cohort pilot study

INTRODUCTION

Overweight and obesity are linked to increased hospitalization and mortality in COVID-19 patients. This study aimed to characterize induced immune responses and deep immune cell profiles stratified by BMI in hospitalized COVID-19 patients.

METHODS AND RESULTS

This observational multicenter cohort pilot study included 122 adult patients with PCR-confirmed COVID-19 in Denmark, stratified by BMI (normal weight, overweight, obese). Inflammation was assessed using TruCulture® and immune cell profiles by flow cytometry with a customized antibody panel (DuraClone®). Patients with obesity had a more pro-inflammatory phenotype with increased TNF-α, IL-8, IL-17, and IL-10 levels post-T cell stimulation, and altered B cell profiles. Patients with obesity showed higher concentrations of naïve, transitional, and non-isotype switched memory B cells, and plasmablasts compared to normal weight patients and healthy controls.

CONCLUSIONS

Obesity in hospitalized COVID-19 patients may correlate with elevated pro-inflammatory cytokines, anti-inflammatory IL-10, and increased B cell subset activation, highlighting the need for further studies.

Host obesity impacts genetic variation in influenza A viral populations

Obesity is well established as a risk factor for many noncommunicable diseases; however, its consequences for infectious disease are poorly understood. Here, we investigated the impact of host obesity on influenza A virus (IAV) genetic variation using a diet-induced obesity ferret model and the A/Hong Kong/1073/1999 (H9N2) strain. Using a co-caging study design, we investigated the maintenance, generation, and transmission of intrahost IAV genetic variation by sequencing viral genomic RNA obtained from nasal wash samples over multiple days of infection. We found evidence for an enhanced role of positive selection acting on de novo mutations in obese hosts that led to nonsynonymous changes that rose to high frequency. In addition, we identified numerous cases of mutations throughout the genome that were specific to obese hosts and that were preserved during transmission between hosts. Despite detection of obese-specific variants, the overall viral genetic diversity did not differ significantly between obese and lean hosts. This is likely due to the high supply rate of de novo variation and common evolutionary adaptations to the ferret host regardless of obesity status, which we show are mediated by variation in the hemagglutinin and polymerase genes (PB2 and PB1). We also identified defective viral genomes (DVGs) that were found uniquely in either obese or lean hosts, but the overall DVG diversity and dynamics did not differ between the two groups. Our study suggests that obesity may result in a unique selective environment impacting intrahost IAV evolution, highlighting the need for additional genetic and functional studies to confirm these effects.IMPORTANCEObesity is a chronic health condition characterized by excess adiposity leading to a systemic increase in inflammation and dysregulation of metabolic hormones and immune cell populations. Influenza A virus (IAV) is a highly infectious pathogen responsible for seasonal and pandemic influenza. Host risk factors, including compromised immunity and pre-existing health conditions, can contribute to increased infection susceptibility and disease severity. During viral replication in a host, the negative-sense single-stranded RNA genome of IAV accumulates genetic diversity that may have important consequences for viral evolution and transmission. Our study provides the first insight into the consequences of host obesity on viral genetic diversity and adaptation, suggesting that host factors associated with obesity alter the selective environment experienced by a viral population, thereby impacting the spectrum of genetic variation.

Metabolic Recovery with the Persistence of Proinflammatory Leucocyte Dysfunction After Bariatric Intervention for Obesity

PURPOSE

A suitable option for severe obesity treatment is a surgical approach. After surgery, metabolic markers and weight frequently return to adequate values; however, concerning systemic inflammatory mediators, the results are inconsistent. Furthermore, it has been suggested that leucocyte function may be affected even after weight normalization. This study aimed to determine if the surgical treatment of obesity influences the production of cytokines by LPS-stimulated as a function of leucocytes.

MATERIALS AND METHODS

We performed a cross-sectional study that investigated the production of cytokines in response to lipopolysaccharide (LPS) along a kinetic of simulation by leucocytes recovered from individuals with normal weight (NW, n = 8), persons living with obesity (Ob, n = 7), persons living with obesity and diabetes mellitus (Ob-DM, n = 17), and persons that used to live with obesity who underwent bypass surgery (fOb + bypass, n = 8) and recover normal weigh.

RESULTS

IL-6 levels were significantly higher in the Ob and fOb + bypass groups than in NW (p = 0.043). IL-10 secretion without LPS was significantly higher in the NW group than in the other groups explored (p < 0.05). When exposed to LPS, the IL-10 levels increased in all groups except the NW group. As also observed for IL-18 and IL-33, the secretion curve of the fOb + bypass group was more similar to the Ob group, even when they had reached normal weight, as opposed to the NW group.

CONCLUSION

Our results show that in patients with fOb + bypass, inflammatory and anti-inflammatory cytokine production dynamics remain disrupted even with improved metabolic control and normal weight recovery.

The impact of metabolic disorders on management of periodontal health in children

Periodontitis is a chronic inflammatory disease caused by plaque biofilm which shares risk factors with systemic chronic diseases such as diabetes, cardiovascular disease, and osteoporosis. Many studies have found increased prevalence and rate of progression of periodontal disease in children with common metabolic disorders. Although the causal relationship and specific mechanism between them has not been determined yet. The aim of this paper is to progress on the impact of metabolic disorders on periodontal health in children and the underlying mechanisms, which provides new evidences for the prevention and intervention of metabolic disorders and periodontitis in children.

Neutrophils: tissue and circulating signatures of pediatric non-alcoholic fatty liver disease

The recent rise in non-alcoholic fatty liver disease (NAFLD) among children and adolescents led to a thorough investigation of the peculiarities of the cellular infiltrate which characterize the disease at young ages. This review aims to highlight the key involvement of neutrophils in the pathogenesis of pediatric NAFLD and the potential biomarker role of neutrophil-to-lymphocyte ratio (NLR) in the same pediatric disorder. Neutrophils, which are first responders to inflammation, constitute an abundant component of an infiltrate which is particularly disposed within the portal area of children with NAFLD. The involvement of neutrophils in triggering liver fibrosis has been related amongst others to reactive oxygen species (ROS) production, to the stimulation of hepatic stellate cells, and to their synthesis of neutrophil elastase. As immune imbalance characterizes NAFLD, potentially emerging non-invasive biomarkers such as NLR have been proposed for the detection and prognosis of NAFLD. In adults, several studies asserted the role of NLR in the prediction of advancing liver fibrosis and mortality in subjects with NAFLD. In children, data is scarce with contradicting findings, as some studies failed to identify significant shifting in NLR values in children with NAFLD when compared with obese controls without liver impairment. However, NLR seems to significantly increase in children with obesity and different degrees of NAFLD when compared to healthy counterparts and their changes seem to be reversible with weight loss. Still, paucity of pediatric studies calls for future research addressing the role of NLR in predicting NAFLD development and progression in children with obesity.

Understanding the Immunological Quality of Breast Milk in Maternal Overweight and Obesity

Maternal obesity, affecting many pregnant women globally, not only poses immediate health risks but also modulates breast milk composition. Obesity is linked to inflammation and oxidative stress, impacting breast milk's immune properties. This paper explores the intricate relationship between maternal metabolic disorders, such as obesity, and breast milk's immunological components. We conducted a thorough search for original and review articles published until 17 October 2023 in the PUBMED/Scopus database. This search included several terms related to human breast milk, immunological properties, and obesity. Articles were selected with the consensus of all authors. Maternal metabolic disorders have discernible effects on the composition of immune-related components in breast milk, such as immunoglobulins, lactoferrin, leptin, ghrelin, adiponectin, C-reactive protein, growth factors, extracellular vesicles, and lymphocytes. These changes in breast milk composition can significantly impact the newborn's immune system, with potential long-term health implications beyond the immediate postnatal period. Maternal metabolic health is a critical factor in shaping the health trajectory of the neonate through breastfeeding, although the full advantages of breastfeeding for children of mothers with obesity remain uncertain. Ongoing research aims to understand and unravel these links.

Seroprevalence of hepatitis A virus antibodies among children and adolescents living in Northern Thailand: an implication for hepatitis A immunization

This cross-sectional study aimed to assess seroprevalence of hepatitis A virus (HAV) antibodies and identify factors associated with HAV seropositivity among children and adolescents aged 1-18 years who resided in Chiang Mai, Thailand. Sociodemographic characteristics, sanitation/hygiene, and history of HAV vaccination were collected. Anti-HAV IgG antibody was determined, and a level ≥ 1.0 S/CO defined HAV seropositivity. We enrolled 300 participants; median age 8.7 years, 54% male, and 13% overweight (BMI z-score: + 1 to + 2 standard deviation [SD]). Sixty-five participants (22%) were vaccinated against HAV. Overall, 84/300 participants (28%) demonstrated HAV seropositivity, of whom 55/65 (85%) and 29/235 (12%) were among vaccinated and unvaccinated participants (P < 0.001), respectively. Previous HAV vaccination (adjusted odds ratio [aOR] 47.2; 95% CI 20.0-111.8) and overweight (aOR 4.4; 95% CI 1.7-11.3, compared with normal weight [BMI z-score: - 2 to + 1 SD]) were significantly associated with seropositivity of HAV. In the stratified analyses, crowded bedroom (aOR 3.2; 95% CI 1.3-7.8, per one person increase) and overweight (aOR 5.0; 95% CI 1.8-13.7) were factors associated with HAV seropositivity among vaccinated and unvaccinated participants, respectively. Seroprevalence of HAV antibodies in healthy Thai children and adolescents was relatively low. Recommendation of HAV vaccination for these populations, particularly those with high-risk conditions, should be considered.

Host obesity impacts genetic variation in influenza A viral populations

Obesity is a chronic health condition characterized by excess adiposity leading to a systemic increase in inflammation and dysregulation of metabolic hormones and immune cell populations. Obesity is well established as a risk factor for many noncommunicable diseases; however, its consequences for infectious disease are poorly understood. Influenza A virus (IAV) is a highly infectious pathogen responsible for seasonal and pandemic influenza. Host risk factors, including compromised immunity and pre-existing health conditions, can contribute to increased infection susceptibility and disease severity. During viral replication in a host, the negative sense single stranded RNA genome of IAV accumulates genetic diversity that may have important consequences for viral evolution and transmission. Here, we investigated the impact of host obesity on IAV genetic variation using a diet induced obesity ferret model. We infected obese and lean male ferrets with the A/Hong Kong/1073/1999 (H9N2) IAV strain. Using a co-caging study design, we investigated the maintenance, generation, and transmission of intrahost IAV genetic variation by sequencing viral genomic RNA obtained from nasal wash samples over multiple days of infection. We found evidence for an enhanced role of positive selection acting on de novo mutations in obese hosts that led to nonsynonymous changes that rose to high frequency. In addition, we identified numerous cases of recurrent low-frequency mutations throughout the genome that were specific to obese hosts. Despite these obese-specific variants, overall viral genetic diversity did not differ significantly between obese and lean hosts. This is likely due to the high supply rate of de novo variation and common evolutionary adaptations to the ferret host regardless of obesity status, which we show are mediated by variation in the hemagglutinin (HA) and polymerase genes (PB2 and PB1). As with single nucleotide variants, we identified a class of defective viral genomes (DVGs) that were found uniquely in either obese or lean hosts, but overall DVG diversity and dynamics did not differ between the two groups. Our study provides the first insight into the consequences of host obesity on viral genetic diversity and adaptation, suggesting that host factors associated with obesity alter the selective environment experienced by a viral population, thereby impacting the spectrum of genetic variation.

Obesity Is Associated with Changes in Laboratory Biomarkers in Chilean Patients Hospitalized with COVID-19

BACKGROUND AND AIMS

It is reported that patients with obesity are more frequently hospitalized for COVID-19, and evidence exists that obesity is a risk factor, regardless of other comorbidities. The objective of this study was to evaluate the association of obesity with changes in laboratory biomarkers in hospitalized Chilean patients.

MATERIALS AND METHODS

A total of 202 hospitalized patients (71 with obesity and 131 without obesity) with a diagnosis of COVID-19 were included in the study. Demographic, clinical, and laboratory (days 1, 3, 7, 15) data were obtained. We performed a statistical analysis, assuming significance with a value of p < 0.05.

RESULTS

Significant differences in chronic respiratory pathology are observed between patients with and without obesity. The inflammatory markers CPR, ferritin, NLR, and PLR are elevated during the evaluated period, while changes in leukocyte populations are present on day 1 (eosinophils) and day 3 (lymphocytes). Finally, a persistent elevation of D-dimer level is observed, presenting significant differences on day 7 between patients with and without obesity. Obesity had a positive correlation with admission to the critical patient unit, invasive mechanical ventilation, and length of hospital stay.

CONCLUSION

Patients with obesity hospitalized for COVID-19 present marked elevations of inflammatory and hemostasis parameters, with a correlation between obesity, changes in laboratory biomarkers, and the risk of adverse clinical outcomes also observed.

Leptin, Adiponectin, and Melatonin Modulate Colostrum Lymphocytes in Mothers with Obesity

Pregnancy complicated by obesity is associated with adverse triggered gestational and neonatal outcomes, with reductions in the subtypes of CD4+ T-lymphocytes representing the modulators of inflammation. It needs to be better established how maternal nutritional statuses impact the neuroendocrine-immune system's action and affect the immunological mechanisms of the maternal-infant relationship via breastfeeding. This study examined the effects of maternal obesity on human colostrum lymphocytes and the intracellular mechanisms of lymphocyte modulation in the presence of leptin, adiponectin, and melatonin via cell proliferation; the release of intracellular calcium; and apoptosis induction. This cross-sectional study analyzed colostrum samples from 52 puerperal splits and divided them into overweight and eutrophic groups. Colostrum lymphocytes underwent immunophenotyping and cell proliferation by flow cytometry and intracellular calcium release and apoptosis assays by immunofluorescence in the presence or absence of hormones. Significant differences were considered when p < 0.05 by the chi-square or t-test. Maternal obesity reduced the population of T-lymphocytes and TCD4+ in human colostrum and proliferative activities (p < 0.05). These hormones restore lymphocyte proliferation to a level similar to the eutrophic group (p < 0.05). Leptin, adiponectin, melatonin hormones, and biological actions consolidated in the scientific literature also represent maternal and infant protection mechanisms via colostrum and the modulation of human colostrum lymphocytes.

Infections and immunity: associations with obesity and related metabolic disorders

About one-fourth of the global population is either overweight or obese, both of which increase the risk of insulin resistance, cardiovascular diseases, and infections. In obesity, both immune cells and adipocytes produce an excess of pro-inflammatory cytokines that may play a significant role in disease progression. In the recent coronavirus disease 2019 (COVID-19) pandemic, important pathological characteristics such as involvement of the renin-angiotensin-aldosterone system, endothelial injury, and pro-inflammatory cytokine release have been shown to be connected with obesity and associated sequelae such as insulin resistance/type 2 diabetes and hypertension. This pathological connection may explain the severity of COVID-19 in patients with metabolic disorders. Many studies have also reported an association between type 2 diabetes and persistent viral infections. Similarly, diabetes favors the growth of various microorganisms including protozoal pathogens as well as opportunistic bacteria and fungi. Furthermore, diabetes is a risk factor for a number of prion-like diseases. There is also an interesting relationship between helminths and type 2 diabetes; helminthiasis may reduce the pro-inflammatory state, but is also associated with type 2 diabetes or even neoplastic processes. Several studies have also documented altered circulating levels of neutrophils, lymphocytes, and monocytes in obesity, which likely modifies vaccine effectiveness. Timely monitoring of inflammatory markers (e.g., C-reactive protein) and energy homeostasis markers (e.g., leptin) could be helpful in preventing many obesity-related diseases.

Adipocyte-mediated epigenomic instability in human T-ALL cells is cytotoxic and phenocopied by epigenetic-modifying drugs

The world’s population with obesity is reaching pandemic levels. If current trends continue, it is predicted that there will be 1.5 billion people with obesity by 2030. This projection is alarming due to the association of obesity with numerous diseases including cancer, with recent studies demonstrating a positive association with acute myeloid leukemia (AML) and B cell acute lymphoblastic leukemia (B-ALL). Interestingly, several epidemiological studies suggest the converse relationship may exist in patients with T cell acute lymphoblastic leukemia (T-ALL). To determine the relationship between obesity and T-ALL development, we employed the diet-induced obesity (DIO) murine model and cultured human T-ALL cells in adipocyte-conditioned media (ACM), bone marrow stromal cell-conditioned media, stromal conditioned media (SCM), and unconditioned media to determine the functional impact of increased adiposity on leukemia progression. Whereas only 20% of lean mice transplanted with T-ALL cells survived longer than 3 months post-inoculation, 50%–80% of obese mice with leukemia survived over this same period. Furthermore, culturing human T-ALL cells in ACM resulted in increased histone H3 acetylation (K9/K14/K18/K23/K27) and methylation (K4me3 and K27me3) posttranslational modifications (PTMs), which preceded accelerated cell cycle progression, DNA damage, and cell death. Adipocyte-mediated epigenetic changes in human T-ALL cells were recapitulated with the H3K27 demethylase inhibitor GSK-J4 and the pan-HDAC inhibitor vorinostat. These drugs were also highly cytotoxic to human T-ALL cells at low micromolar concentrations. In summary, our data support epidemiological studies demonstrating that adiposity suppresses T-ALL pathogenesis. We present data demonstrating that T-ALL cell death in adipose-rich microenvironments is induced by epigenetic modifications, which are not tolerated by leukemia cells. Similarly, GSK-J4 and vorinostat treatment induced epigenomic instability and cytotoxicity profiles that phenocopied the responses of human T-ALL cells to ACM, which provides additional support for the use of epigenetic modifying drugs as a treatment option for T-ALL.

Increased Surgical Site Subcutaneous Fat Thickness Is Associated with Infection after Posterior Cervical Fusion

Background: Previous literature has associated increased body mass index (BMI) with risk of surgical site infection (SSI) after posterior cervical fusion (PCF) surgery. However, few studies have examined the association between local adiposity and risk of SSI, re-admission, and re-operation after PCF. Local adiposity is easily measured on pre-operative magnetic resonance imaging (MRI) and may act as a more accurate predictor compared with BMI. Patients and Methods: Subjects undergoing PCF from 2013-2018 at a single institution were identified retrospectively. Posterior cervical subcutaneous fat thickness, paraspinal muscle thickness, and lamina-to-skin distance measurements were obtained from computed tomography (CT) or MRI scans. Subjects with active infection, malignancy, or revision procedures were excluded. Results: Two hundred five patients were included with 20 developing SSIs. Subjects with SSIs had a longer fusion construct (4.90 vs. 3.71 levels; p = 0.001), higher Elixhauser comorbidity index (ECI; 2.05 vs. 1.34; p = 0.045), had a history of diabetes mellitus (30% vs. 10.8%; p = 0.026), higher subcutaneous fat thickness (30.5 vs. 23.6 mm; p = 0.013), and higher lamina-to-skin distance (66.4 vs. 57.9 mm; p = 0.027). Subcutaneous fat thickness (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.01-1.10]; p = 0.026) and lamina-to-skin distance (OR, 1.05; 95% CI, 1.01-1.09]; p = 0.014) were associated with SSI in multivariable analysis. A subcutaneous fat thickness cutoff value of 23.2 mm had 90% sensitivity and 54.1% specificity for prediction of SSI. There was no association need for re-admission or re-operation. Conclusions: Increased posterior cervical fat may increase the risk of SSI after PCF. Pre-operative advanced imaging may be a valuable tool for assisting with patient counseling, optimization, and risk stratification.

BMI in early adulthood is associated with severe COVID-19 later in life: A prospective cohort study of 1.5 million Swedish men

OBJECTIVE

Overweight and obesity have been identified as risk factors for severe COVID-19; however, prospective cohort studies investigating the association between overweight early in life and severity of COVID-19 are lacking.

METHODS

This study included 1,551,670 Swedish men, born between 1950 and 1987, with BMI registered at age 18 years. They were followed until January 9, 2021. COVID-19 cases and comorbidities were identified through the National Patient, Intensive Care, and Cause of Death registries. Outcomes included the following: 1) hospitalization; 2) intensive care unit admission; and 3) death.

RESULTS

The study found 4,315 cases (mean age = 56.4 years [SD 8.8]) of patients hospitalized because of COVID-19, of which 729 were admitted to an intensive care unit, and altogether there were 224 deaths. The risk for hospital admission increased with higher values of BMI at age 18 years, despite adjustment for comorbidities, from an odds ratio (OR) of 1.19 (95% CI: 1.08-1.31) at BMI = 22.5 to 25 to an OR of 1.68 (95% CI: 1.39-2.02) at BMI ≥ 30, compared with BMI = 18.5 to 20. ORs for intensive care unit admission were 1.44 (95% CI: 1.13-1.84) at BMI = 22.5 to 25 and 2.61 (95% CI: 1.73-3.93) at BMI ≥ 30.

CONCLUSIONS

Higher BMI in early adulthood was associated with severe COVID-19 many years later, with a risk increase starting already at BMI ≥ 22.5. This underlines the necessity of preventive actions against overweight in youth to offer protection against coming viral pandemics.

Egg-Phosphatidylcholine Attenuates T-Cell Dysfunction in High-Fat Diet Fed Male Wistar Rats

Obesity is associated with immune dysfunction including an impaired T-cell function characterized by a lower IL-2 (proliferation marker) production after stimulation. Phosphatidylcholine (PC), a form of choline mostly found in eggs, has been shown to beneficially modulate T-cell responses during the lactation period by increasing the production of IL-2. To determine the impact of egg-PC as part of a high-fat diet on immune function we randomly fed male Wistar rats one of three diets containing the same amount of total choline but differing in the form of choline: 1-Control low fat [CLF, 10% wt/wt fat, 100% free choline (FC)]; 2- Control high-fat (CHF, 25% wt/wt fat, 100% FC); 3- PC high-fat (PCHF, 25% wt/wt, 100% PC). After 9 weeks of feeding, rats were euthanized. Cell phenotypes and ex vivo cytokine production by splenocytes stimulated with phorbol 12-myristate 13-acetate plus ionomycin (PMA+I), lipopolysaccharide (LPS) and pokeweed (PWM) were measured by flow cytometry and ELISA, respectively. Rats fed the PCHF diet had a lower proportion of CD3+ cells when compared to both the CLF and the CHF. Following PMA+I stimulation, splenocytes from the CHF group produced less IL-2 and TNF-α compared to CLF and PCHF groups. No significant differences in cytokine production were found among groups after LPS and PWM stimulation. Our results show that feeding a high-fat diet impairs T-cell responses, as measured by ex vivo cytokine production, which can be attenuated by providing egg-PC.

COVID-19 and obesity: the meeting of two pandemics

COVID-19 and obesity are two pandemic diseases that the world is currently facing. Both activate the immune system and mediate inflammation. A sequence of disease phases in patients with severe COVID-19 results in a cytokine storm, which amplifies the subclinical inflammation that already exists in patients with obesity. Pro-inflammatory cytokines and chemotactic factors increase insulin resistance in obesity. Therefore, a greater systemic inflammatory response is establishe, along with an increased risk of thrombotic phenomena and hyperglycemic conditions. These changes further impair pulmonary, cardiac, hepatic, and renal functions, in addition to hindering glycemic control in people with diabetes and pre-diabetes. This review explains the pathophysiological mechanisms of these two pandemic diseases, provides a deeper understanding of this harmful interaction and lists possible therapeutic strategies for this risk group.

Review of the recent clinical trials for PD-1/PD-L1 based lung cancer immunotherapy

INTRODUCTION

Lung cancer is known for its high mortality rate and prevalence in the world today. For decades, chemotherapy has been used as the main treatment for this cancer, but this has changed over time. Immune checkpoint inhibitors (ICIs) such as programmed death 1 and programmed death-ligand 1 (PD-1/PD-L1) blocking agents have been assessed in numerous clinical trials as single or combination therapy and have shown overall promising results. Nevertheless, various challenges have been encountered, which cast doubts over this method.

AREAS COVERED

We provide an introduction to the mechanisms underlying the PD-1/PD-L1 pathway. Then, we discuss the latest results from the most leading-edge studies evaluating PD-1/PD-L1 inhibitors in different lines of lung cancer therapy (some of which have gained FDA approval), potential biomarkers, and major challenges of ICI therapy.

EXPERT OPINION

Currently, the standard of care (SoC) for lung cancer consists mostly of chemotherapeutics. With further studies and ongoing trials evaluating novel ICI therapy, FDA has been approving specific ICI therapeutics, including PD-1/PD-L1 inhibitors, for particular types of lung cancer. However, for ICIs to play a key role in SoC, we need to overcome the major challenges of ICI therapy.

The healthy behaviours and COVID-19 mortality among Iranian women: a case-control study

BACKGROUND

Women are among the susceptible groups to Coronavirus disease-19 (COVID-19) in Ardabil, north-west of Iran, despite the current global status. The underlying causes of high incidence and fatality rate of women in Ardabil are not fully understood. Hence, this study aimed to investigate the healthy behaviours in women of Ardabil and its relationship with COVID-19 mortality.

METHODS

We conducted a case-control study to compare the adherence to health protocols and behaviours with respect to COVID-19 between the infected (261 patients) and healthy (515 persons) women. Health protocols and behaviours such as using mask, gloves, disinfectants, history of travelling and contacting, and attending various gatherings and places during the COVID-19 pandemic along with demographic variables were defined as independent variables, and COVID-19 death rate was defined as the dependent variable. Multivariable logistic regression methods were used to explore the risk factors associated with COVID-19 mortality.

RESULTS

Chi-square and Fisher tests showed significant differences between infected and healthy women in terms of history of contact and traveling (p < 0.05), wearing mask (p < 0.001), going to work place (p < 0.001), and attend public gatherings (p = 0.038). Multivariable logistic regression disclosed that the age group over 80 years: 8.97 times (95% CI 2.27-29.85), women with underlying chronic diseases: 4.14 times (95% CI 1.61-10.64), and obese women: 3.01 times (95% CI 1.04-6.03) were more likely to die from COVID-19 than other women.

CONCLUSION

Considering the high incidence and mortality rate in Ardabil women due to COVID-19 and the corresponding health behavioural factors, special emphasis should be given to the increase of women awareness on the importance of healthy behaviours, diet, and life-style.

Mucosal-Associated Invariant T Cell Response to Acute Exercise and Exercise Training in Older Obese Women

(1) Background: Obesity is a major global public health concern as it is associated with many of the leading causes of preventable deaths. Exercise reduces obesity-induced inflammation; however, it is unknown how exercise training may impact mucosal associated invariant T (MAIT) cells in overweight/obese (OW) post-menopausal women. Therefore, the purpose of this study was to investigate (i) circulating MAIT-cells at rest in OW vs. Lean women, (ii) the response of MAIT-cells to a single bout of combined aerobic and resistance exercise, and (iii) the effects of 12 weeks of exercise training (EX) or educational program (ED) on the MAIT-cell response in OW. (2) Methods: OW completed an acute exercise session or sitting control, underwent 12 weeks of exercise training or received educational materials, and then repeated the exercise session/sitting control. Lean post-menopausal women provided a baseline comparison. (3) Results: OW had lower circulating MAIT-cells at rest than Lean prior to exercise training; however, after training EX displayed improved MAIT-cell frequency. Additionally, prior to training EX did not exhibit MAIT-cell mobilization/egress, however, both improved after training. (4) Conclusions: Reduced MAIT-cell frequency and ability to mobilize/egress were potentially partially rescued in EX after 12 weeks of exercise training; however, further research is needed to elucidate age or obesity-induced attenuations in MAIT-cells.

COVID-19, body mass index and cholesterol: an ecological study using global data

Background

Coronavirus disease 2019 (COVID-19) is now globally considered a serious economic, social and health threat. A wide range of health related factors including Body Mass Index (BMI) is reported to be associated with the disease. In the present study, we analyzed global databases to assess the correlation of BMI and cholesterol with the risk of COVID-19.

Methods

In this ecological study, we used age-standardized BMI and cholesterol levels as well as the incidence and mortality ratio of COVID-19 at the national-levels obtained from the publicly available databases such as the World Health Organization (WHO) and NCD Risk Factor Collaboration (NCD-RisC). Bivariate correlation analysis was applied to assess the correlations between the study variables. Mean differences (standard deviation: SD) of BMI and cholesterol levels of different groups were tested using independent sample t-test or Mann–Whitney rank test as appropriate. Multivariable linear regression analysis was performed to identify variables affecting the incidence and mortality ratio of COVID-19.

Results

Incidence and mortality ratio of COVID-19 were significantly higher in developed (29,639.85 ± 20,210.79 for cases and 503.24 ± 414.65 for deaths) rather than developing (8153.76 ± 11,626.36 for cases and 169.95 ± 265.78 for deaths) countries (P < 0.01). Results indicated that the correlations of BMI and cholesterol level with COVID-19 are stronger in countries with younger population. In general, the BMI and cholesterol level were positively correlated with COVID-19 incidence ratio (β = 2396.81 and β = 30,932.80, p < 0.01,‌ respectively) and mortality ratio (β = 38.18 and β = 417.52, p < 0.05,‌ respectively) after adjusting for socioeconomic and demographic factors.

Conclusion

Countries with higher BMI or cholesterol at aggregate levels had a higher ratios of COVID-19 incidence and mortality. The aggregated level of cholesterol and BMI are important risk factors for COVID-19 major outcomes, especially in developing countries with younger populations. We recommend monitoring and promotion of health indicices to better prevent morbidity and mortality of COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11715-7.

The Role of Obesity in the Immunopathogenesis of COVID-19 Respiratory Disease and Critical Illness

Coronavirus disease (COVID-19), the clinical syndrome caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is currently a global health pandemic with substantial morbidity and mortality. COVID-19 has cast a shadow on nearly every aspect of society, straining health systems and economies across the world. Although it is widely accepted that a close relationship exists between obesity, cardiovascular disease, and metabolic disorders on infection, we are only beginning to understand ways in which the immunological sequelae of obesity functions as a predisposing factor related to poor clinical outcomes in COVID-19. As both the innate and adaptive immune systems are each primed by obesity, the alteration of key pathways results in both an immunosuppressed and hyperinflammatory state. The present review will discuss the cellular and molecular immunology of obesity in the context of its role as a risk factor for severe COVID-19, discuss the role of cytokine storm, and draw parallels to prior viral epidemics such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and 2009 H1N1.

Associations of Body Composition and Physical Activity Level With Multiple Measures of Epigenetic Age Acceleration

Epigenetic clocks use DNA methylation to estimate biological age. Whether body composition and physical activity are associated with these clocks is not well understood. Using blood samples collected at enrollment (2003-2009) from 2,758 women in the US nationwide Sister Study, we calculated 6 epigenetic age acceleration metrics using 4 epigenetic clocks (Hannum, Horvath, PhenoAge, GrimAge). Recreational physical activity was self-reported, and adiposity measures were assessed by trained medical examiners (body mass index (BMI), waist-to-hip ratio (WtH), waist circumference). In cross-sectional analyses, all adiposity measures were associated with epigenetic age acceleration. The strongest association was for BMI and PhenoAge, a measure of biological age that correlates with chronic disease (BMI of ≥35.0 vs. 18.5-24.9, β = 3.15 years, 95% confidence interval (CI): 2.41, 3.90; P for trend < 0.001). In a mutual-adjustment model, both were associated with PhenoAge age acceleration (BMI of ≥35.0 vs. 18.5-24.9, β = 2.69 years, 95% CI: 1.90, 3.48; P for trend < 0.001; quartile 4 vs.1 WtH, β = 1.00 years, 95% CI: 0.34, 1.65; P for trend < 0.008). After adjustment, physical activity was associated only with GrimAge (quartile 4 vs. 1, β = -0.42 years, 95% CI: -0.70, -0.14; P for trend = 0.001). Physical activity attenuated the waist circumference associations with PhenoAge and GrimAge. Excess adiposity was associated with epigenetic age acceleration; physical activity might attenuate associations with waist circumference.

A High-Fat Diet Increases Influenza A Virus-Associated Cardiovascular Damage

BACKGROUND

Influenza A virus (IAV) causes a wide range of extrarespiratory complications. However, the role of host factors in these complications of influenza virus infection remains to be defined.

METHODS

Here, we sought to use transcriptional profiling, virology, histology, and echocardiograms to investigate the role of a high-fat diet in IAV-associated cardiac damage.

RESULTS

Transcriptional profiling showed that, compared to their low-fat counterparts (LF mice), mice fed a high-fat diet (HF mice) had impairments in inflammatory signaling in the lung and heart after IAV infection. This was associated with increased viral titers in the heart, increased left ventricular mass, and thickening of the left ventricular wall in IAV-infected HF mice compared to both IAV-infected LF mice and uninfected HF mice. Retrospective analysis of clinical data revealed that cardiac complications were more common in patients with excess weight, an association which was significant in 2 out of 4 studies.

CONCLUSIONS

Together, these data provide the first evidence that a high-fat diet may be a risk factor for the development of IAV-associated cardiovascular damage and emphasizes the need for further clinical research in this area.

Obesity and Prevalence of Latent Tuberculosis: A Population-Based Survey

OBJECTIVE

Diminution in body weight is a known risk factor that increases the burden of active tuberculosis (TB). However, conflicting evidence exists for the effect of body weight on the risk of latent tuberculosis infection (LTBI). The objective of the present study is to examine the prevalence of LTBI at different body weights, evaluate the extent of association between body mass index (BMI) and LTBI and identify factors mediating this relationship in an adult population.

METHODS

We conducted a cross-sectional study to estimate the relationship between BMI and LTBI in participants from the US-National Health and Nutrition Examination Survey (NHANES; 2012, n = 5156; 514 with LTBI and 4642 controls).

RESULTS

The association between BMI and levels of cardiometabolic risk markers in both LTBI and control groups had a similar profile. When adjusted for age and sex, BMI was significantly inversely correlated with the prevalence of LTBI (r = -0.147, P < .001). Effect of BMI on the risk of LTBI was evaluated using multivariate logistic regression models adjusted for age, sex, diabetes, and level of education. In this model, increasing BMI was significantly associated with lower risk of LTBI (OR = 0.85; 95%CI: 0.77-0.96, P < .01).

CONCLUSION

This study further establishes an inverse relationship between BMI and prevalence of LTBI. Decreased BMI can be considered as a risk factor in LTBI, the reservoir for active TB cases.

Impact of obesity and SARS-CoV-2 infection: implications for host defence - a living review

The role of obesity in the pathophysiology of respiratory virus infections has become particularly apparent during the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, where obese patients are twice as likely to suffer from severe coronavirus disease 2019 (COVID-19) than healthy weight individuals. Obesity results in disruption of systemic lipid metabolism promoting a state of chronic low-grade inflammation. However, it remains unclear how these underlying metabolic and cellular processes promote severe SARS-CoV-2 infection. Emerging data in SARS-CoV-2 and Influenza A virus (IAV) infections show that viruses can further subvert the host's altered lipid metabolism and exploit obesity-induced alterations in immune cell metabolism and function to promote chronic inflammation and viral propagation. In this review, we outline the systemic metabolic and immune alterations underlying obesity and discuss how these baseline alterations impact the immune response and disease pathophysiology. A better understanding of the immunometabolic landscape of obese patients may aid better therapies and future vaccine design.

Factors associated with 30-day soft tissue complications following upper extremity sarcoma surgery

BACKGROUND AND OBJECTIVES

The incidence of soft tissue complications following sarcoma surgery in the upper extremity is reportedly high. Therefore, this study assessed the National Surgical Quality Improvement Program (NSQIP) database to identify independent risk factors, while also reporting the incidence of soft tissue complications in the first 30 days after surgery.

METHODS

A total of 620 patients that underwent surgical treatment for upper extremity sarcoma were included from the NSQIP database. Soft tissue complications were defined as surgical site infection, wound dehiscence, or soft-tissue related reoperations. Clinically relevant patient and treatment characteristics were selected and analyzed.

RESULTS

The 30-day soft tissue complication rate was 4.7%. In the multivariable analysis, higher body mass index (p = .047) and longer operative times (p = .002) were independently associated with soft tissue complications.

CONCLUSIONS

Higher body mass index and longer operative times are risk factors for soft tissue complications following upper extremity sarcoma surgery. The soft-tissue complication rate following resection of upper extremity tumors is low in this national cohort, possibly due to the relatively small tumor size and low prevalence of radiotherapy.

Peripheral Markers of Depression

Major Depressive Disorder (MDD) is a leading cause of disability worldwide, creating a high medical and socioeconomic burden. There is a growing interest in the biological underpinnings of depression, which are reflected by altered levels of biological markers. Among others, enhanced inflammation has been reported in MDD, as reflected by increased concentrations of inflammatory markers-C-reactive protein, interleukin-6, tumor necrosis factor-α and soluble interleukin-2 receptor. Oxidative and nitrosative stress also plays a role in the pathophysiology of MDD. Notably, increased levels of lipid peroxidation markers are characteristic of MDD. Dysregulation of the stress axis, along with increased cortisol levels, have also been reported in MDD. Alterations in growth factors, with a significant decrease in brain-derived neurotrophic factor and an increase in fibroblast growth factor-2 and insulin-like growth factor-1 concentrations have also been found in MDD. Finally, kynurenine metabolites, increased glutamate and decreased total cholesterol also hold promise as reliable biomarkers for MDD. Research in the field of MDD biomarkers is hindered by insufficient understanding of MDD etiopathogenesis, substantial heterogeneity of the disorder, common co-morbidities and low specificity of biomarkers. The construction of biomarker panels and their evaluation with use of new technologies may have the potential to overcome the above mentioned obstacles.

Gene expression of the immunoinflammatory and immunological status of obese dogs before and after weight loss

Obesity is characterized by a low degree of chronic inflammation state that, along with metabolic modifications, promotes important changes in the animal's organism. Adipose tissue actively participates in inflammation and immunity, and several defense cells of the organism may, therefore, be involved in the diversity found between obese and ideal weight individuals. Studies regarding this subject have shown immune cell changes in humans and rats, however, the literature is scarce in relation to dogs. Thus, the present study aimed to evaluate the gene expression profile of immunoinflammatory response and the lymphoproliferation of obese dogs before and after weight loss. Eight female dogs, neutered, of different breeds, aged between 1 and 8 years (4.74±3.19), obese, with body condition score (BCS) of 9 out of a 9-point scale and body composition determined by the deuterium isotope dilution method were included. The obese dogs were enrolled in a weight loss program and after losing 20% of their initial weight became a second experimental group. A third experimental group consisted of eight female dogs, neutered, aged between 1 and 8 years (3.11±0.78) and with ideal BCS (5 out of a 9-point scale). Gene expression of immunoinflammatory cytokines (resistin, leptin, adiponectin, TNF-α, IL-6, IL-8, and IL-10) was assessed by qRT-PCR and immunity was assessed by lymphoproliferative response using the flow cytometry technique. The data that presented normal distribution was evaluated by analysis of variance by the PROC MIXED of the SAS and when differences were detected, these were compared by the Tukey test. Regarding the gene expression data, the procedure PROC GLIMMIX was adopted and the methodology of generalized linear model was used, in which the Gama distribution proved to be adequate. Values of p<0.05 were considered significant. The mean weight loss period of the animals included in the study was 194.25 ± 28.31 days and the mean weekly weight loss rate was 1.02 ± 0.82%. The average fat mass, both in percentage (P<0.001) and in kilograms (P = 0.012), was higher in the obese group (40.88%; 8.91kg), returning to normal and without difference between the control group (19.16%; 3.01kg) and after weight loss (22.10%; 4.11kg). The weight loss program resulted in an increase in percentage of lean body mass (P = 0.001), 55.50% in obese animals vs 77.90% in obese dogs after weight loss, the latter with no difference when compared to the control group (80.84%). The obese group presented increased gene expression of resistin and IL-8 in relation to the weight loss group (P = 0.002). In adiponectin, the obese group presented increased mRNA gene expression when compared to the weight loss group (P = 0.003). The evaluation of lymphocyte proliferation showed differences between the group of obese animals before and after weight loss (P = 0.004). Weight loss resulted in an increase in the lymphoproliferation rate (18.48%) compared to obese dogs at the beginning of the study (10.71%). These results indicate that weight loss modulates the immunoinflammatory response of obese dogs and may present important benefits to health and longevity of dogs.

Systematic analysis for the relationship between obesity and tuberculosis

OBJECTIVES

Underweight or low body mass index (BMI) is an established risk factor for active tuberculosis. Recent evidence, however, suggests that overweight is associated with lower incidence of tuberculosis. The objective of this systematic review and meta-analysis is to understand the relationship between obesity and tuberculosis and document the extent of association between the two conditions over the range of BMI from underweight to obesity.

METHODS

A comprehensive literature search was conducted to identify studies reporting prevalence of the different BMIs in patients with tuberculosis and controls. Thirty studies of adult humans reporting the incidence of tuberculosis at different weight categories were selected for inclusion for meta-analysis in the present study.

RESULTS

In tuberculosis, the prevalence of underweight was 3-fold higher than that in controls (P = 0.001) whereas the proportion of overweight and obesity was 2-fold lower (P = 0.001). One unit increase in BMI was associated with 2% reduction in tuberculosis incidence (P < 0.001). Adjusted odds ratio of tuberculosis was 4.96 (95% confidence interval: 4.87-5.05) in underweight and 0.26 in obesity.

CONCLUSION

This study further establishes low body weight as a risk factor for tuberculosis whilst overweight and obesity are associated with lower disease risk. Body weight can be considered as a prognostic indictor in the clinical course of tuberculosis.

Facial appearance and metabolic health biomarkers in women

Facial appearance has been suggested to provide an honest cue of an individual’s biological condition. However, there is little direct evidence that facial attractiveness reflects actual health. Here we tested if facial appearance is related with metabolic health biomarkers. Face photographs of 161 healthy, young women (M_age = 28.59, SD_age = 2.34) were assessed in terms of perceived attractiveness and health. Metabolic health was evaluated based on levels of markers of lipid and glucose metabolism balance, liver functioning, and inflammation. BMI, testosterone (T), and estradiol (E2) levels were controlled. Facial attractiveness, but not health, was negatively related with lipid profile components detrimental to health (total cholesterol, LDL, triglycerides) but not with relatively protective for health HDL. When controlled for BMI, E2, and T, only the relationship between attractiveness and triglycerides remained significant. Facial appearance was unrelated with glucose metabolism, liver functioning, and inflammatory markers. The results suggest, that for healthy women of reproductive age, such measures as BMI and sex hormone levels may be better predictors of attractiveness, compared to measures of metabolic health. Markers of lipid, glucose homeostasis, liver functioning or low-grade inflammation may be rather indicators of future health, of lesser importance in mating context, thus only modestly reflected in facial appearance.

Thoracoscopic radical surgery for a morbidly obese patient with early lung cancer after laparoscopic sleeve gastrectomy: a case report

Background

We experienced a case of early stage lung cancer involving a morbidly obese patient. Obesity is associated with a higher incidence of surgical complications. We examined the effectiveness of laparoscopic sleeve gastrectomy as a primary weight loss procedure in a morbidly obese patient who required oncological surgery.

Case presentation

A 64-year-old morbidly obese female with a body mass index of 43.5 kg/m² was referred to our hospital to undergo weight loss. A right-sided lung mass was found incidentally on computed tomography conducted in preparation for laparoscopic sleeve gastrectomy, which was performed prior to tumor surgery. As a result, weight loss was achieved within 2.5 months after the laparoscopic sleeve gastrectomy, and the patient’s type-2 diabetes, hypertension, and dyslipidemia, which are linked to obesity, were markedly ameliorated. After a quick intraoperative pathological inspection revealed that the tumor was malignant, thoracoscopic right lung superior lobe resection was performed safely.

Conclusions

Laparoscopic sleeve gastrectomy proved to be a powerful approach in a case in which a morbidly obese patient with early stage cancer needed to lose weight rapidly.

Obesity is associated with increased susceptibility to influenza A (H1N1pdm) but not H3N2 infection

BACKGROUND

Obesity has been shown to increase the risk of severe outcomes and death for influenza virus infections. However, we don't understand the influence of obesity on susceptibility to infection or on non-severe influenza outcomes.

METHODS

We performed a case-ascertained, community-based study of influenza transmission within households in Nicaragua. To investigate whether obesity increases the likelihood of influenza infection and symptomatic infection we use logistic regression models.

RESULTS

Between 2015 and 2018, a total of 335 index cases with influenza A and 1,506 of their household contacts were enrolled. Obesity was associated with increased susceptibility to symptomatic H1N1pdm infection among adults (OR: 2.10, 95%CI: 1.08-4.06), but not children, and this association increased with age. Among adults with H1N1pdm infection, obesity was associated with increased likelihood of symptoms (OR: 3.91, 95%CI: 1.55-9.87). For middle aged and older adults with obesity there was also a slight increase in susceptibility to any H1N1pdm infection (OR: 1.20, 95%CI: 0.62-2.34). Body Mass Index (BMI) was also linearly associated with increased susceptibility to symptomatic H1N1pdm infection, primarily among middle aged and older adult women (5-unit BMI increase OR: 1.40, 95%CI: 1.00-1.97). Obesity was not associated with increased H3N2 susceptibility or associated symptoms.

CONCLUSIONS

We found that among adults obesity is associated with susceptibility to H1N1pdm infection and with symptoms associated with H1N1pdm infection, but not with susceptibility to H3N2 infection or associated symptoms. These findings will help target prevention efforts and therapeutics to this high-risk population.

A Complex Systems Model of Breast Cancer Etiology: The Paradigm II Conceptual Model

BACKGROUND

The etiology of breast cancer is a complex system of interacting factors from multiple domains. New knowledge about breast cancer etiology continues to be produced by the research community, and the communication of this knowledge to other researchers, practitioners, decision makers, and the public is a challenge.

METHODS

We updated the previously published Paradigm model (PMID: 25017248) to create a framework that describes breast cancer etiology in four overlapping domains of biologic, behavioral, environmental, and social determinants. This new Paradigm II conceptual model was part of a larger modeling effort that included input from multiple experts in fields from genetics to sociology, taking a team and transdisciplinary approach to the common problem of describing breast cancer etiology for the population of California women in 2010. Recent literature was reviewed with an emphasis on systematic reviews when available and larger epidemiologic studies when they were not. Environmental chemicals with strong animal data on etiology were also included.

RESULTS

The resulting model illustrates factors with their strength of association and the quality of the available data. The published evidence supporting each relationship is made available herein, and also in an online dynamic model that allows for manipulation of individual factors leading to breast cancer (https://cbcrp.org/causes/).

CONCLUSIONS

The Paradigm II model illustrates known etiologic factors in breast cancer, as well as gaps in knowledge and areas where better quality data are needed.

IMPACT

The Paradigm II model can be a stimulus for further research and for better understanding of breast cancer etiology.

The potential impacts of obesity on COVID-19

Obese patients are at increased risk of exacerbations from viral respiratory infections. During the H1N1 pandemic, obesity was associated with an increased risk of influenza-associated intensive care unit (ICU) admission and death, longer duration of mechanical ventilation, and longer duration of ICU and hospital length of stay compared with the non-obese. These observations have raised a concern about the correlation between obesity and the current COVID-19 pandemic. In this review, we have outlined the potential impacts of obesity on respiratory physiology and the function of both innate and adaptive immune responses. Also, it has been clearly illustrated that obese patients are potentially more vulnerable to COVID-19 and more contagious than lean patients. The comorbidities associated with obesity were found to be correlated with a severe clinical course of COVID-19 and increased mortality and high BMI has been shown to be correlated with hospitalisation, the need for mechanical ventilation and non-survival. The review also sheds light on the challenges that obese patients pose for healthcare providers inside and outside ICUs.

Inflammatory markers in depression: A meta-analysis of mean differences and variability in 5,166 patients and 5,083 controls

IMPORTANCE

The magnitude and variability of cytokine alterations in depression are not clear.

OBJECTIVE

To perform an up to date meta-analysis of mean differences of immune markers in depression, and to quantify and test for evidence of heterogeneity in immune markers in depression by conducting a meta-analysis of variability to ascertain whether only a sub-group of patients with depression show evidence of inflammation.

DATA SOURCES

Studies that reported immune marker levels in peripheral blood in patients with depression and matched healthy controls in the MEDLINE database from inception to August 29th 2018 were examined.

STUDY SELECTION

Case-control studies that reported immune marker levels in peripheral blood in patients with depression and healthy controls were selected.

DATA EXTRACTION AND SYNTHESIS

Means and variances (SDs) were extracted for each measure to calculate effect sizes, which were combined using multivariate meta-analysis.

MAIN OUTCOMES AND MEASURES

Hedges g was used to quantify mean differences. Relative variability of immune marker measurements in patients compared with control groups as indexed by the coefficient of variation ratio (CVR).

RESULTS

A total of 107 studies that reported measurements from 5,166 patients with depression and 5,083 controls were included in the analyses. Levels of CRP (g = 0.71; 95%CI: 0.50-0.92; p < 0.0001); IL-3 (g = 0.60; 95%CI: 0.31-0.89; p < 0.0001); IL-6 (g = 0.61; 95%CI: 0.39-0.82; p < 0.0001); IL-12 (g = 1.18; 95%CI: 0.74-1.62; p < 0.0001); IL-18 (g = 1.97; 95%CI: 1.00-2.95; p < 0.0001); sIL-2R (g = 0.71; 95%CI: 0.44-0.98; p < 0.0001); and TNFα (g = 0.54; 95%CI: 0.32-0.76; p < 0.0001) were significantly higher in patients with depression. These findings were robust to a range of potential confounds and moderators. Mean-scaled variability, measured as CVR, was significantly lower in patients with depression for CRP (CVR = 0.85; 95%CI: 0.75-0.98; p = 0.02); IL-12 (CVR = 0.61; 95%CI: 0.46-0.80; p < 0.01); and sIL-2R (CVR = 0.85; 95%CI: 0.73-0.99; p = 0.04), while it was unchanged for IL-3, IL-6, IL-18, and TNF α.

CONCLUSIONS AND RELEVANCE

Depression is confirmed as a pro-inflammatory state. Some of the inflammatory markers elevated in depression, including CRP and IL-12, show reduced variability in patients with depression, therefore supporting greater homogeneity in terms of an inflammatory phenotype in depression. Some inflammatory marker elevations in depression do not appear due to an inflamed sub-group, but rather to a right shift of the immune marker distribution.

Immunological Implications of Physical Inactivity among Older Adults during the COVID-19 Pandemic

Social distancing has been adopted worldwide to control severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission. Social isolation is likely to lead to a decline in physical activity, which could result in immune system dysfunction, thereby increasing infection susceptibility and exacerbating the pathophysiology of conditions that are common among older adults, including cardiovascular disease, cancer, and inflammatory disorders. Older adults and people living with these comorbidities are at a greater risk for complications during coronavirus disease 2019 (COVID-19). In this review, we discuss the negative impact of physical inactivity on immune function and showcase evidence that regular physical activity may be an effective strategy to counter some of the deleterious effects of social isolation. Furthermore, we briefly highlight key research questions in exercise immunology, with a focus on older adults in the context of COVID-19. Although it is worth emphasizing that there is no direct evidence that physical activity can prevent or treat ­COVID-19, promoting an active lifestyle is a key intervention to counteract the effects of social isolation, especially in older adults and other at-risk individuals, such as those living with chronic diseases associated with ageing and lifestyle.

Implant-induced inflammatory angiogenesis is up-regulated in obese mice

The damaging effects of obesity extend to multiple pre-existing tissue/organs. However, the influence of this condition on key components (inflammation and angiogenesis) of fibrovascular connective proliferating tissue, essential in repair processes, has been neglected. Our objective in this study was to investigate whether obesity would influence inflammatory-angiogenesis induced by synthetic matrix of polyether-polyurethane implanted subcutaneously in high-fat-fed obese C57/BL6 mice. Fourteen days after implantation, the inflammatory and angiogenic components of the newly formed tissue intra-implant were evaluated. The pro-inflammatory enzyme activities, myeloperoxidase (MPO) and N-acetyl-β-D-glucosaminidase (NAG), the levels of TNF-α, CXCL1/KC and CCL2 and NF-κB transcription factor were examined. Angiogenesis was determined by morphometric analysis of implant blood vessels, intra-implant levels of hemoglobin content, VEGF levels, and western blot for VEGFR2. All inflammatory and angiogenic markers were increased in the implants of obese mice compared with their non-obese counterparts. Similarly, activation of the NF-κB pathway and phosphorylation of VEGFR2 were higher in implants of obese mice (1.60 ± 0.28 Np65/Cp65; 0.96 ± 0.08 p-VEGFR2/VEGFR2-T) compared with implants of non-obese animals (1.40 ± 0.14; 0.49 ± 0.08). These observations suggest that obesity exerts critical role in sponge-induced inflammatory-angiogenesis, possibly by activating fibrovascular components in the inflamed microenvironment. Thus, this pathological condition causes damage not only to pre-existing tissues/organs but also to newly formed proliferating fibrovascular tissue. This is relevant to the development of therapeutic approaches to improve healing processes in patients with obesity.

T cell-mediated regulation of the microbiota protects against obesity

The microbiota influences obesity, yet organisms that protect from disease remain unknown. During studies interrogating host-microbiota interactions, we observed the development of age-associated metabolic syndrome (MetS). Expansion of Desulfovibrio and loss of Clostridia were key features associated with obesity in this model and are present in humans with MetS. T cell-dependent events were required to prevent disease, and replacement of Clostridia rescued obesity. Inappropriate immunoglobulin A targeting of Clostridia and increased Desulfovibrio antagonized the colonization of beneficial Clostridia. Transcriptional and metabolic analysis revealed enhanced lipid absorption in the obese host. Colonization of germ-free mice with Clostridia, but not Desulfovibrio, down-regulated genes that control lipid absorption and reduced adiposity. Thus, immune control of the microbiota maintains beneficial microbial populations that constrain lipid metabolism to prevent MetS.

Obesity-Associated Alterations of Natural Killer Cells and Immunosurveillance of Cancer

Obesity is accompanied by a systemic chronic low-grade inflammation as well as dysfunctions of several innate and adaptive immune cells. Recent findings emphasize an impaired functionality and phenotype of natural killer (NK) cells under obese conditions. This review provides a detailed overview on research related to overweight and obesity with a particular focus on NK cells. We discuss obesity-associated alterations in subsets, distribution, phenotype, cytotoxicity, cytokine secretion, and signaling cascades of NK cells investigated in vitro as well as in animal and human studies. In addition, we provide recent insights into the effects of physical activity and obesity-associated nutritional factors as well as the reduction of body weight and fat mass on NK cell functions of obese individuals. Finally, we highlight the impact of impaired NK cell physiology on obesity-associated diseases, focusing on the elevated susceptibility for viral infections and increased risk for cancer development and impaired treatment response.

Perinatal complications and executive dysfunction in early-onset schizophrenia

BACKGROUND

The present study examined the association between perinatal obstetric complications and executive dysfunction in early-onset schizophrenia (EOS), compared to healthy controls. Higher incidences of obstetric complications and more severe executive dysfunctions characterize EOS. Research shows extensive brain maturation in newborns, suggesting them to be particularly vulnerable for perinatal insults. Executive function is mainly mediated by the prefrontal cortex, an area that matures last during pregnancy. Thus, exposure to perinatal complications may influence executive dysfunction in EOS.

METHODS

The participants were 19 EOS patients and 54 healthy controls. Executive function was assessed with the D-KEFS Color Word Interference Test and the Wisconsin Card Sorting Test. Information on perinatal obstetric complications and Apgar 5-min scores were obtained from the Norwegian Medical Birth Registry. Associations between perinatal conditions and executive function were studied using stepwise regression analyses.

RESULTS

Perinatal complications, and especially shorter gestational lengths, were significantly associated with significant executive dysfunctions in EOS. Perinatal complications did not affect executive function among healthy controls. A significant relationship between lower Apgar 5-min scores and executive dysfunction was found among both EOS patients and healthy controls.

CONCLUSIONS

Exposure to perinatal complications, and particularly a shorter gestational length, was associated with increased executive dysfunction in EOS. Exposed healthy controls did not exhibit similar executive difficulties, suggesting that the EOS patients seemed especially vulnerable for executive deficits due to perinatal insults. The findings indicate that EOS youths learn more slowly and experience more difficulty with problem-solving, which carry important implications for clinical practice. Lower Apgar 5-min scores were associated with executive dysfunction in both groups. Low Apgar score at 5 min may therefore be an important early indicator of executive difficulties among adolescents, independent of diagnosis.

Obesity-Related Microenvironment Promotes Emergence of Virulent Influenza Virus Strains

Obesity is associated with increased disease severity, elevated viral titers in exhaled breath, and significantly prolonged viral shed during influenza A virus infection. Due to the mutable nature of RNA viruses, we questioned whether obesity could also influence influenza virus population diversity. Here, we show that minor variants rapidly emerge in obese mice. The variants exhibit increased viral replication, resulting in enhanced virulence in wild-type mice. The increased diversity of the viral population correlated with decreased type I interferon responses, and treatment of obese mice with recombinant interferon reduced viral diversity, suggesting that the delayed antiviral response exhibited in obesity permits the emergence of a more virulent influenza virus population. This is not unique to obese mice. Obesity-derived normal human bronchial epithelial (NHBE) cells also showed decreased interferon responses and increased viral replication, suggesting that viral diversity also was impacted in this increasing population.IMPORTANCE Currently, 50% of the adult population worldwide is overweight or obese. In these studies, we demonstrate that obesity not only enhances the severity of influenza infection but also impacts viral diversity. The altered microenvironment associated with obesity supports a more diverse viral quasispecies and affords the emergence of potentially pathogenic variants capable of inducing greater disease severity in lean hosts. This is likely due to the impaired interferon response, which is seen in both obese mice and obesity-derived human bronchial epithelial cells, suggesting that obesity, aside from its impact on influenza virus pathogenesis, permits the stochastic accumulation of potentially pathogenic viral variants, raising concerns about its public health impact as the prevalence of obesity continues to rise.

Lack of Differences in Inflammation and T Cell-Mediated Function between Young and Older Women with Obesity

Both obesity and aging are associated with dysregulated immune and inflammatory responses. There is limited knowledge, however, on differences in the immune system between young and older adults with obesity. The goal of this study was to compare circulating inflammatory cytokines and T cell-mediated immune response between young and older women with obesity. Twenty-three young (23–43 years) and 21 older (60–83 years) women with obesity were recruited at the Weight and Wellness Center at Tufts Medical Center. Circulating inflammatory cytokines (CRP, IL-6, and IL-1β) and ex vivo indicators of T cell-mediated immune function were compared between the groups. Older women with obesity had significantly fewer circulating CD3+, CD8+, CD19+, and natural killer T (NKT) cells compared to young women with obesity (p = 0.016, p < 0.0001, p = 0.0003, and p < 0.0001, respectively). However, with few exceptions, there was no significant difference in inflammation markers or stimulated lymphocyte proliferation and cytokine production by peripheral blood mononuclear cells between young and older participants. These findings are in contrast to those previously reported in young and old subjects with healthy weight and call for further investigation into the impact of obesity on premature aging of the immune system.

An Integrative Proteomic/Lipidomic Analysis of the Gold Nanoparticle Biocorona in Healthy and Obese Conditions

Introduction: When nanoparticles (NPs) enter a physiological environment, a coating of biomolecules or biocorona (BC) forms on the surface. Formation of the NP-BC is dependent on NP properties, the physiological environment, and time. The BC influences NP properties and biological interactions such as cellular internalization, immune responses, biodistribution, and others, leading to pharmacological and toxicological consequences. To date, examination of the NP-BC has focused primarily on protein components and healthy conditions. Therefore, we evaluated the protein and lipid content of BCs that formed on physicochemically distinct gold nanoparticles (AuNPs) under healthy and obese conditions. A comprehensive understanding of the NP-BC is necessary for the translation of in vitro toxicity assessments to clinical applications. Materials and Methods: AuNPs with two coatings (poly-N-vinylpyrrolidone [PVP] or citrate) and diameters (20 or 100 nm) were incubated in pooled human serum, and an integrated proteomic/lipidomic approach was used to evaluate BC composition. Macrophages were utilized to evaluate differential immune responses due to variations in the AuNP-BC. Results: AuNPs form distinct BCs based on physicochemical properties and the surrounding environment, with the obese BC containing more proteins and fewer lipids than the healthy BC. Differential macrophage inflammatory responses were observed based on AuNP properties and BC composition. Discussion and Conclusion: Overall, these findings demonstrate that AuNP size and coating, as well as physiological environment, influence the protein and lipid composition of the BC, which impacts cellular responses following exposure. These findings demonstrate that incorporation of BCs representing distinct physiological conditions may enhance the translatability of nanosafety in vitro studies.

Obesity and adiposity indicators in asthma and allergic rhinitis in children

PURPOSE OF REVIEW

The prevalence of obesity and allergic diseases, such as asthma and allergic rhinitis, is increasing worldwide not only in adults, but also in children. Experimental and clinical studies have demonstrated the effect of obesity not only on asthma, but also on other allergic diseases.

RECENT FINDINGS

Allergic diseases, such as asthma and allergic rhinitis, are common chronic inflammatory diseases of the airways. Obesity is an increasingly common pediatric disease and is a risk factor for the development of asthma in that obese patients with asthma tend to have more severe asthma that does not respond well to standard asthma therapy. On the contrary, children with asthma maybe at a high risk of obesity, suggesting that the relationship of asthma and obesity seems to be interrelated. The role of obesity on the development of allergic rhinitis is not well defined, whereas allergic rhinitis may have an impact on obesity.

SUMMARY

Childhood obesity is often considered to be less serious than obesity in adults because of the greater risk of complications in obese adults. In this review, we discuss the allergic confounders of obesity and the impact of allergic diseases on obesity. Proper control of the BMI within the normal range in children with allergic diseases is important.

The association of obesity and serum leptin levels with complete blood count and some serum biochemical parameters in Iranian overweight and obese individuals

Background: Obesity has been suggested to be well correlated with altered levels of complete blood count (CBC) parameters. In this study, the relationship of body mass index (BMI) and circulating leptin levels with CBC among obese and overweight adults was examined. Methods: CBC and biochemical parameters, WBC and hematological profiles, leptin levels, related factors to liver, and kidney and lipid profiles were measured among 184 obese and overweight people aged 18-60 years. Statistical analysis was performed using SPSS software. To assess the normality of data, the Kolmogorov-Smirnov test was used. Logarithmic transformation was performed for some variables with non-normal distribution. The association between 2 quantitative variables was measured using bivariate correlation (Pearson or Spearman). Pearson correlations and multiple regression analysis were performed to assess the correlation between variables. Simple and multiple regression analyses were performed to predict some variables. P- value <0.05 was considered significant. Results: Hematocrit, insulin, fasting blood sugar, uric acid, TG, LDL-C, VLDL-C, and ALT were positively correlated with BMI (p=0.041, r=0.149 for hematocrit; p≤0.001, r=0.520 for insulin; p≤0.001, r=0.363 for FBS; p≤0.001, r=0.309 for uric acid; p=0.015, r=0.189 for TG; p=0.030, r=161 for LDL-C; p=0.019, r=0.181 for VLDL-C; p≤0.001, r=0.299 for ALT), whereas urea and HDL-C were negatively correlated with BMI (p≤0.001, r=-0.368 for urea; p≤0.001, r=-0.297 for HDL-C). Moreover, LDL-C and insulin were positively correlated with leptin (P = 0.011, r = 0.194 for LDL-C, P = 0.013, r = 0.114 for insulin) and hematocrit, urea, creatinine, TG and VLDL-C were negatively correlated with leptin (p=0.040, r=-0.162 for hematocrit; p≤0.001, r=-0.305 for urea; p=0.007, r=-0.219 for creatinine; p=0.025, r=0.188 for TG; p=0.007, r=-0.218 for VLDL-C). Our analysis showed that white blood cell was positively correlated with leptin (β=17.36, p=0.048). Also, other CBC parameters had no significant correlations with BMI and leptin. Conclusion: According to the findings of this study, BMI had a negative association with urea and HDL-C, while BMI had a positive association with insulin, hematocrit, FBS, uric acid, TG, VLDL-C, LDL-C, and ALT. Furthermore, leptin had a negative association with hematocrit, creatinine, and urea, TG, VLDL-C and a positive association with LDL-C and insulin among the participants of this study.

Obesity as an Inflammatory Agent Can Cause Cellular Changes in Human Milk due to the Actions of the Adipokines Leptin and Adiponectin

Adiponectin and leptin play roles in the hunger response, and they can induce the inflammatory process as the initial mechanism of the innate immune response. It is possible for alterations in the levels of these adipokines to compromise the functional activity of human colostrum phagocytes. Therefore, the objective of this study is to analyze the effects of adiponectin and leptin on colostrum mononuclear (MN) cells. Colostrum was collected from 80 healthy donors, who were divided into two groups: the control group and the high body mass index (BMI) group. MN cells were used to analyze phagocytosis by flow cytometry, and reactive oxygen species (ROS), intracellular calcium, and apoptosis were assessed by fluorimetry using a microplate reader. Adipokines restored the levels of phagocytosis to the high BMI group (p < 0.05), with a mechanism that is action-dependent on the release of ROS and intracellular calcium. However, adiponectin and leptin simultaneously contributed to better microbicidal activity, thus reflecting an increase in the apoptosis level (p < 0.05) in the high BMI group. Probably, the maintenance of the balance between adiponectin and leptin levels enhances the protection and decreases the indices of neonatal infection in the breastfeeding infants of women with high BMI values. Therefore, policies that support pre-gestational weight control should be encouraged.

Impact of Obesity on Influenza A Virus Pathogenesis, Immune Response, and Evolution

With the rising prevalence of obesity has come an increasing awareness of its impact on communicable disease. As a consequence of the 2009 H1N1 influenza A virus pandemic, obesity was identified for the first time as a risk factor for increased disease severity and mortality in infected individuals. Over-nutrition that results in obesity causes a chronic state of meta-inflammation with systemic implications for immunity. Obese hosts exhibit delayed and blunted antiviral responses to influenza virus infection, and they experience poor recovery from the disease. Furthermore, the efficacy of antivirals and vaccines is reduced in this population and obesity may also play a role in altering the viral life cycle, thus complementing the already weakened immune response and leading to severe pathogenesis. Case studies and basic research in human cohorts and animal models have highlighted the prolonged viral shed in the obese host, as well as a microenvironment that permits the emergence of virulent minor variants. This review focuses on influenza A virus pathogenesis in the obese host, and on the impact of obesity on the antiviral response, viral shed, and viral evolution. We comprehensively analyze the recent literature on how and why viral pathogenesis is altered in the obese host along with the impact of the altered host and pathogenic state on viral evolutionary dynamics in multiple models. Finally, we summarized the effectiveness of current vaccines and antivirals in this populations and the questions that remain to be answered. If current trends continue, nearly 50% of the worldwide population is projected to be obese by 2050. This population will have a growing impact on both non-communicable and communicable diseases and may affect global evolutionary trends of influenza virus.

Influenza in obese travellers: increased risk and complications, decreased vaccine effectiveness

BACKGROUND

Obesity is a worldwide epidemic and was empirically shown to increase the risk of developing severe influenza virus infection. As international travel becomes more common and obesity is now prevalent even in low- and middle-income countries, travellers may have an increased risk of contracting influenza virus especially during peak influenza season.

METHODS

An analysis of the literature, centred on publications from 2014-19, was performed, with an emphasis on human epidemiological data, human studies ex vivo and studies in mouse models of obesity. Our search efforts focused on influenza disease severity, pathogenesis, evolutionary dynamics and measures of infection control in the obese and overweight host.

RESULTS

Obesity is associated with an increased risk of infection, as well as a greater chance for hospitalization and severe complications. Studies in mouse models of obesity have uncovered that obese hosts suffer increased viral spread, delayed viral clearance and heightened damage to the respiratory epithelium. Innate and adaptive immune responses are delayed, thus increasing morbidity and mortality. Further, infection control measures, including vaccination and antivirals, prove less effective in obese hosts. Finally, the obese microenvironment allows for increased duration and amount of viral shedding and potentially increases the chance for emergence of virulent minor variants in the viral population. Together, obese hosts are at high risk of influenza infection, as well as severe sequelae following infection.

CONCLUSION

Obese travellers should be aware of influenza activity in the regions visited, as well as take protective measures prior to travel. Vaccination is highly recommended for all travellers, but especially highly susceptible obese travellers.