Gender differences and inflammation: an in vitro model of blood cells stimulation in prepubescent children

Sex differences in associations of metabolic inflammation and insulin resistance with incident type 2 diabetes mellitus: a retrospective cohort of adults with annual health examinations

BACKGROUND AND AIMS

Cardio-kidney-metabolic diseases are major causes of premature death worldwide, with type 2 diabetes mellitus (T2DM) playing a critical role. Inflammation and insulin resistance have been implicated in the pathogenesis of T2DM. This study aimed to investigate the sex-specific associations of metabolic inflammation and insulin resistance with incident T2DM to support personalized prevention and management strategies.

METHODS

A retrospective cohort was used to analyse annual health examination data from the general practice department of a general hospital in Shanghai between 2021 and 2023. After excluding participants diagnosed with T2DM, cardiovascular disease or chronic kidney disease at baseline, 1214 adults were followed up for two years. Cox proportional hazards and logistic regression models were used to assess the associations of triglyceride-glucose body mass index (TyG-BMI), the lymphocyte/high-density lipoprotein cholesterol ratio (LHR), the monocyte/high-density lipoprotein cholesterol ratio (MHR), and the neutrophil/high-density lipoprotein cholesterol ratio (NHR) with incident T2DM.

RESULTS

In the total population, TyG-BMI (all HR/OR > 1, P < 0.05), LHR, MHR and NHR were significantly and positively associated with incident T2DM. TyG-BMI was significantly associated with incident T2DM in men (both HR/OR > 1, P < 0.05), whereas LHR, MHR and NHR were strongly associated with incident T2DM in women (all HR/OR > 1, P < 0.05). The interaction effect between LHR and sex was statistically significant.

CONCLUSION

Sex differences play an important role in incident T2DM. Men should be aware of weight control to avoid obesity-related insulin resistance, whereas women should monitor metabolic inflammation indicators such as LHR for early detection and intervention of their T2DM risk.

Exposure to volatile organic compounds and growth indicators in adolescents: Unveiling the association and potential intervention strategies

Environmental pollutant is considered to be one of the important factors affecting adolescent growth. However, the effects of volatile organic compounds (VOCs) exposure on adolescent growth have not been assessed. Data from the National Health and Nutrition Examination Survey (NHANES) 2011-2018 was used to examine the associations between VOCs exposure and adolescent growth indicators through three statistical models. The mediating effect of bone mineral density (BMD) on these associations was examined. The potential pathways and key targets were identified by the network pharmacology analysis methods. This study included 746 adolescents. Three statistical methods consistently showed a negative correlation between VOCs exposure and adolescent growth indicators. Furthermore, BMD mediated the relationship between VOCs exposure and adolescent growth indicators, with mediated proportion ranging from 4.3 % to 53.4 %. Network pharmacology analysis found a significant enrichment in IL-17 signaling pathway. Moreover, the adverse effects of VOCs exposure on adolescent growth were observed to significantly attenuate in adolescents with high serum vitamin D levels. Our results suggested that VOCs exposure was an adverse factor affecting adolescent growth, with BMD playing a significant regulatory role, and IL-17 signaling pathway was the underlying mechanism. Vitamin D supplementation may be a viable strategy to prevent VOCs exposure from affecting adolescent growth.

Sex diferences in serum and synovial fluid C-reactive protein concentration in healthy dogs

Differences between serum C-reactive protein (SCRP) and synovial fluid C-reactive protein (SFCRP) concentrations in healthy animals may be influenced by the sex of the individual and associated with various factors. The objective of this study was to evaluate the disparities in SCRP and SFCRP concentrations between females and males, as well as within each sex. Sixty healthy dogs (N = 60), comprising both sexes, were enrolled in the study. Peripheral blood and knee synovial fluid samples were collected for SCRP and SFCRP analysis, respectively. Serum C-reactive protein (SCRP) and SFCRP concentrations were measured, with mean of 9.61 ± 4.96 mg/L for SCRP and 1.28 ± 3.05 mg/L for SFCRP. Notably, SFCRP concentrations were consistently lower than SCRP concentrations in both sexes. Statistically significant differences were observed between sexes for both SCRP (P = 0.021) and SFCRP (P = 0.007). Further analysis within females revealed statistically significant differences between SCRP and SFCRP concentrations (P = 0.002), whereas in males, such differences were not significant (P = 0.175). Additionally, weak correlations were found between SCRP and SFCRP concentrations for both sexes (females r = 0.07; males r = 0.29). Joint capsule thickness was assessed using ultrasonography, revealing thicker joint capsules in males. A robust positive association was noted between joint capsule thickness and the SFCRP concentration in both sexes. These findings offer valuable insights into the dynamics of CRP in the context of joint health in male and female patients, elucidating the underlying pathological mechanisms of joint disease and inflammation. Overall, this underscores the importance of considering sex-specific factors in the assessment and management of joint health, as well as in the design and interpretation of studies involving SFCRP concentrations.

Granulocyte- Macrophage Colony-Stimulating Factor Reverses Immunosuppression Acutely Following a Traumatic Brain Injury and Hemorrhage Polytrauma in a Juvenile Male Rat Model

Traumatic brain injury (TBI) is a common cause of morbidity and mortality in children. We have previously shown that TBI with a concurrent extracranial injury reliably leads to post-injury suppression of the innate and adaptive immune systems. In patients with post-injury immune suppression, if immune function could be preserved, this might represent a therapeutic opportunity. As such, we examined, in an animal injury model, whether systemic administration of granulocyte macrophage colony-stimulating factor (GM-CSF) could reverse post-injury immune suppression and whether treatment was associated with neuroinflammation or functional deficit. Prepubescent male rats were injured using a controlled cortical impact model and then subjected to removal of 25% blood volume (TBI/H). Sham animals underwent surgery without injury induction, and the treatment groups were sham and injured animals treated with either saline vehicle or 50 μg/kg GM-CSF. GM-CSF was administered following injury and then daily until sacrifice at post-injury day (PID) 7. Immune function was measured by assessing tumor necrosis factor-α (TNF-α) levels in whole blood and spleen following ex vivo stimulation with pokeweed mitogen (PWM). Brain samples were assessed by multiplex enzyme-linked immunosorbent assay (ELISA) for cytokine levels and by immunohistochemistry for microglia and astrocyte proliferation. Neuronal cell count was examined using cresyl violet staining. Motor coordination was evaluated using the Rotarod performance test. Treatment with GM-CSF was associated with a significantly increased response to PWM in both whole blood and spleen. GM-CSF in injured animals did not lead to increases in levels of pro-inflammatory cytokines in brain samples but was associated with significant increases in counted astrocytes. Finally, while injured animals treated with saline showed a significant impairment on behavioral testing, injured animals treated with GM-CSF performed similarly to uninjured animals. GM-CSF treatment in animals with combined injury led to increased systemic immune cell response in whole blood and spleen in the acute phase following injury. Improved immune response was not associated with elevated pro-inflammatory cytokine levels in the brain or functional impairment.

Sex-related immunity: could Toll-like receptors be the answer in acute inflammatory response?

An increasing number of studies have highlighted the existence of a sex-specific immune response, wherein men experience a worse prognosis in cases of acute inflammatory diseases. Initially, this sex-dependent inflammatory response was attributed to the influence of sex hormones. However, a growing body of evidence has shifted the focus toward the influence of chromosomes rather than sex hormones in shaping these inflammatory sex disparities. Notably, certain pattern recognition receptors, such as Toll-like receptors (TLRs), and their associated immune pathways have been implicated in driving the sex-specific immune response. These receptors are encoded by genes located on the X chromosome. TLRs are pivotal components of the innate immune system, playing crucial roles in responding to infectious diseases, including bacterial and viral pathogens, as well as trauma-related conditions. Importantly, the TLR-mediated inflammatory responses, as indicated by the production of specific proteins and cytokines, exhibit discernible sex-dependent patterns. In this review, we delve into the subject of sex bias in TLR activation and explore its clinical implications relatively to both the X chromosome and the hormonal environment. The overarching objective is to enhance our understanding of the fundamental mechanisms underlying these sex differences.

The influence of neonatal BCG vaccination on in vitro cytokine responses to Plasmodium falciparum

BACKGROUND

Bacillus Calmette-Guérin (BCG) vaccination has off-target protective effects against infections unrelated to tuberculosis. Among these, murine and human studies suggest that BCG vaccination may protect against malaria. We investigated whether BCG vaccination influences neonatal in vitro cytokine responses to Plasmodium falciparum. Blood samples were collected from 108 participants in the Melbourne Infant Study BCG for Allergy and Infection Reduction (MIS BAIR) randomised controlled trial (Clinical trials registration NCT01906853, registered July 2013), seven days after randomisation to neonatal BCG (n = 66) or no BCG vaccination (BCG-naïve, n = 42). In vitro cytokine responses were measured following stimulation with P. falciparum-infected erythrocytes (PfIE) or E. coli.

RESULTS

No difference in the measured cytokines were observed between BCG-vaccinated and BCG-naïve neonates following stimulation with PfIE or E. coli. However, age at which blood was sampled was independently associated with altered cytokine responses to PfIE. Being male was also independently associated with increased TNF-a responses to both PfIE and E. coli.

CONCLUSION

These findings do not support a role for BCG vaccination in influencing in vitro neonatal cytokine responses to P. falciparum. Older neonates are more likely to develop P. falciparum-induced IFN-γ and IFN-γ-inducible chemokine responses implicated in early protection against malaria and malaria pathogenesis.

Inflammation and cytomegalovirus viremia during pregnancy drive sex-differentiated differences in mortality and immune development in HIV-exposed infants

Children who are HIV-exposed but uninfected have increased infectious mortality compared to HIV-unexposed children, raising the possibility of immune abnormalities following exposure to maternal viraemia, immune dysfunction, and co-infections during pregnancy. In a secondary analysis of the SHINE trial in rural Zimbabwe we explored biological pathways underlying infant mortality, and maternal factors shaping immune development in HIV-exposed uninfected infants. Maternal inflammation and cytomegalovirus viraemia were independently associated with infant deaths: mortality doubled for each log10 rise in maternal C-reactive protein (adjusted hazard ratio (aHR) 2.09; 95% CI 1.33-3.27), and increased 1.6-fold for each log10 rise in maternal cytomegalovirus viral load (aHR 1.62; 95% CI 1.11-2.36). In girls, mortality was more strongly associated with maternal C-reactive protein than cytomegalovirus; in boys, mortality was more strongly associated with cytomegalovirus than C-reactive protein. At age one month, HIV-exposed uninfected infants had a distinct immune milieu, characterised by raised soluble CD14 and an altered CD8 + T-cell compartment. Alterations in immunophenotype and systemic inflammation were generally greater in boys than girls. Collectively, these findings show how the pregnancy immune environment in women with HIV underlies mortality and immune development in their offspring in a sex-differentiated manner, and highlights potential new intervention strategies to transform outcomes of HIV-exposed children. ClinicalTrials.gov/NCT01824940.

Gendered Impact of Age, Toilet Facilities, and Cooking Fuels on the Occurrence of Acute Respiratory Infections in Toddlers in Indonesia and the Philippines

INTRODUCTION

The purpose of the study was to analyze the risk factors of acute respiratory infections (ARI) in children under five in Indonesia and the Philippines and to implement a primary review of the characteristics of toddlers and their households in both countries.

METHODS

Data were obtained from the 2017 Demographic and Health Survey (DHS) of Indonesia and the Philippines. The characteristics of children, mothers, and households were analyzed using bivariate and multivariate logistic regression to examine the significant correlations between variables.

RESULTS

The percentage of children under five with ARI symptoms in 2017 was 1.51% in the Philippines and 4.22% in Indonesia. In Indonesia, males aged under one year had significantly lower occurrences of ARI symptoms (OR 0.54, 95% CI 0.36-0.82). In the Philippines, dirty cooking fuels had a significant effect on increasing the likelihood of ARI in female toddlers (OR 4.01, 95% CI 1.02-15.83). In the Philippines, the unavailability of toilet facilities had a significant effect on increasing the likelihood of ARI in male toddlers (OR 2.67, 95% CI 1.15-6.16).

CONCLUSION

The comparison of risk factors between male and female toddlers revealed different results in some variables, as follows: children aged under one year, dirty cooking fuels, and unavailable toilet facilities. The role of parents is fundamental in taking care of female toddlers, since they are more exposed to ARI at the age of under one year and are more prone to indoor air pollution from solid cooking fuels.

From infection to repair: Understanding the workings of our innate immune cells

In a world filled with microbes, some posing a threat to our body, our immune system is key to living a healthy life. The innate immune system is made of various cell types that act to guard our bodies. Unlike the adaptive immune system that has a specific response, our innate immune system encompasses cells that elicit unspecific immune responses, triggered whenever the right signals are detected. Our understanding of immunity started with the concept of our immune system only responding to "nonself" like the pathogens that invade our body. However, over the past few decades, we have learned that the immune system is more than an on/off switch that recognizes nonself. The innate immune system regularly patrols our bodies for pathogens and tissue damage. Our innate immune system not only seeks to resolve infection but also repair tissue injury, through phagocytosing debris and initiating the release of growth factors. Recently, we are starting to see that it is not just recognizing danger, our innate immune system plays a crucial role in repair. Innate immune cells phenotypically change during repair. In the context of severe injury or trauma, our innate immune system is modified quite drastically to help repair, resulting in reduced infection control. Moreover, these changes in immune cell function can be modified by sex as a biological variable. From past to present, in this overview, we provide a summary of the innate immune cells and pathways in infection and tissue repair. This article is categorized under: Immune System Diseases > Molecular and Cellular Physiology.

Innate Immune Activation and Circulating Inflammatory Markers in Preschool Children

Early childhood is characterised by repeated infectious exposures that result in inflammatory responses by the innate immune system. In addition, this inflammatory response to infection is thought to contribute to the epidemiological evidence linking childhood infection and adult non-communicable diseases. Consequently, the relationship between innate immune responses and inflammation during early life may inform prevention of NCDs later in life. In adults, non-genetic host factors such as age, sex, and obesity, strongly impact cytokine production and circulating mediators, but data in children are lacking. Here, we assessed cytokine responses and inflammatory markers in a population of healthy preschool children (mean age 4.2 years). We studied associations between cytokines, plasma inflammatory markers and non-genetic host factors, such as sex, age, adiposity, season, and immune cell composition. Similar to adults, boys had a higher inflammatory response than girls, with IL-12p70 and IL-10 upregulated following TLR stimulation. Adiposity and winter season were associated with increased circulating inflammatory markers but not cytokine production. The inflammatory markers GlycA and hsCRP were positively associated with production of a number of cytokines and may therefore reflect innate immune function and inflammatory potential. This dataset will be informative for future prospective studies relating immune parameters to preclinical childhood NCD phenotypes.

Gut Barrier Dysfunction and Type 2 Immunity: Implications for Compulsive Behavior

To date, much of the focus of gut-brain axis research has been on gut microbiota regulation of anxiety and stress-related behaviors. Much less attention has been directed to potential connections between gut microbiota and compulsive behavior. Here, we discuss a potential link between gut barrier dysfunction and compulsive behavior that is mediated through "type 2" rather than "type 1" inflammation. We examine connections between compulsive behavior and type 2 inflammation in Tourette syndrome, obsessive-compulsive disorder, autism, addiction, and post-traumatic stress disorder. Next, we discuss potential connections between gut barrier dysfunction, type 2 inflammation, and compulsive behavior. We posit a potential mechanism whereby gut barrier dysfunction-associated type 2 inflammation may drive compulsive behavior through histamine regulation of dopamine neurotransmission. Finally, we discuss the possibility of exploiting the greater accessibility of the gut relative to the brain in identifying targets to treat compulsive behavior disorders.

Unraveling the Mystery of COVID-19 Postvaccination Myocarditis: A Systematic Review of Current Cases

From the early stages of the pandemic, the development and mass production of a safe and effective vaccine seemed like the greatest tool, to win the fight against the virus. In the present study, we comprehensively conducted a systematic review of all current cases worldwide to better understand whether there is a link between COVID-19 vaccination and one of the most devastating complications, cardiac Inflammation. Our search retrieved over 250 results, of which 130 met the inclusion criteria, and their respective data were extracted. The results suggest that postvaccination myocarditis and pericarditis are more likely to be seen in male, younger, and mRNA-vaccinated individuals. Most affected patients experienced symptoms following the second shot, and complaint of chest pain was the most prevalent presentation. Currently, no direct link can be drawn between the vaccines and the risk of cardiac inflammation.

The Effects of Maternal Smoking on Pregnancy and Offspring: Possible Role for EGF?

Cigarette smoke exposure during pregnancy and lactation is associated with adverse pregnancy outcomes. Here, we investigated the effects of maternal smoke exposure on pregnancy and offspring immunity and explored whether, epidermal growth factor (EGF), an important growth-promoting factor in human colostrum and milk, might be a possible missing link in maternal smoke exposure and changes in infants’ immune responses. Pregnant BALB/c mice were exposed to either cigarette smoke or air during gestation and lactation, and effects on pulmonary inflammation in dams and immune responses in offspring were examined. Maternal smoke exposure increased airway hyperresponsiveness and accumulation of inflammatory cells in the lungs of pregnant dams compared to non-pregnant dams. The E-cadherin protein expression was reduced in mammary glands of cigarette smoke-exposed pregnant dams. EGF levels were higher in mammary glands and serum of smoke-exposed pregnant dams compared to air-exposed pregnant dams. Offspring from cigarette smoke-exposed dams exhibited elevated levels of IL-17A, MCP-1, IL-22, and IL-13 in anti-CD3 stimulated spleen cell culture supernatants. EGF levels were also increased in serum of offspring from smoke-exposed dams. A positive correlation was observed between serum EGF levels and neutrophil numbers in bronchoalveolar lavage fluid of the dams. Interestingly, IL-17A, MCP-1, IL-22, IL13, and IFN-γ levels in anti-CD3 stimulated spleen cell culture supernatants of male pups also showed a positive correlation with EGF serum levels. In summary, our results reveal that maternal smoke exposure predisposes dams to exacerbated airway inflammation and offspring to exacerbated immune responses and both phenomena are associated with elevated EGF concentrations.

The Effects of Biological Sex on Sepsis Treatments in Animal Models: A Systematic Review and a Narrative Elaboration on Sex- and Gender-Dependent Differences in Sepsis

Preclinical studies provide an opportunity to evaluate the relationship between sex and sepsis, and investigate underlying mechanisms in a controlled experimental environment. The objective of our systematic review was to assess the impact of biological sex on treatment response to fluid and antibiotic therapy in animal models of sepsis. Furthermore, we provide a narrative elaboration of sex-dependent differences in preclinical models of sepsis.

DATA SOURCES

MEDLINE and Embase were searched from inception to March 16, 2020.

STUDY SELECTION

All studies reporting sex-stratified data comparing antibiotics and/or fluid resuscitation with a placebo or no treatment arm in an in vivo model of sepsis were included.

DATA EXTRACTION

Outcomes of interest were mortality (primary) and organ dysfunction (secondary). Risk of bias was assessed. Study selection and data extraction were conducted independently and in duplicate.

DATA SYNTHESIS

The systematic search returned 2,649 unique studies, and two met inclusion criteria. Both studies used cecal ligation and puncture models with imipenem/cilastatin antibiotics. No eligible studies investigated fluids. In one study, antibiotic therapy significantly reduced mortality in male, but not female, animals. The other study reported no sex differences in organ dysfunction. Both studies were deemed to be at a high overall risk of bias.

CONCLUSIONS

There is a remarkable and concerning paucity of data investigating sex-dependent differences in fluid and antibiotic therapy for the treatment of sepsis in animal models. This may reflect poor awareness of the importance of investigating sex-dependent differences. Our discussion therefore expands on general concepts of sex and gender in biomedical research and sex-dependent differences in key areas of sepsis research such as the cardiovascular system, immunometabolism, the microbiome, and epigenetics. Finally, we discuss current clinical knowledge, the potential for reverse translation, and directions for future studies.

REGISTRATION

PROSPERO CRD42020192738.

Sex Differences in Respiratory Viral Pathogenesis and Treatments

Biological sex affects the outcome of diverse respiratory viral infections. The pathogenesis of respiratory infections caused by viruses ranging from respiratory syncytial virus to influenza viruses and severe acute respiratory syndrome coronavirus 2 differs between the sexes across the life course. Generally, males are more susceptible to severe outcomes from respiratory viral infections at younger and older ages. During reproductive years (i.e., after puberty and prior to menopause), females are often at greater risk than males for severe outcomes. Pregnancy and biological sex affect the pathogenesis of respiratory viral infections. In addition to sex differences in the pathogenesis of disease, there are consistent sex differences in responses to treatments, with females often developing greater immune responses but experiencing more adverse reactions than males. Animal models provide mechanistic insights into the causes of sex differences in respiratory virus pathogenesis and treatment outcomes, where available. Expected final online publication date for the Annual Review of Virology, Volume 8 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Gender differences in patients with severe dental infections presenting to hospital

Introduction Gender differences have been documented in prevalence and morbidity of caries, gingivitis and oral health, but not previously in cervicofacial infection. Identification and minimisation of gender inequalities is a World Health Organisation priority, and there are physiological, behavioural and cultural reasons to suspect that sex and gender differences may be present.Methods Analysis was carried out of the MTReC National Snapshot audit of cervicofacial infections. This database was created by oral and maxillofacial surgery trainees in 2017 and records over 400 variables in 1,002 individual patients admitted to hospital with severe odontogenic infection.Results Records were available for 1,002 patients with cervicofacial infection (456 females and 546 males). There were significant differences between recorded gender in those presenting with airway compromise (male 7% vs female 2%, p = 0.001), severe inflammatory response syndrome (male 60% vs female 39%, p = 0.007) and requirement for awake fibre-optic intubation on admission (male 4% vs female 1%, p = 0.014).Discussion These results suggest that male patients access healthcare later in their disease than female patients, and with more severe systemic compromise. This may be due to prevalent cultural and behavioural norms. As equality of access is the responsibility of the administrator, we discuss methods which might improve timely presentation in males with cervicofacial infections.

Selective inflammatory propensities in adopted adolescents institutionalized as infants

This study examined whether early life adversity (ELA) limited to infancy was associated with an increase in circulating levels of proinflammatory cytokines and cellular cytokine responses to three stimulants [lipopolysaccharide (LPS), phytohemagglutinin (PHA), and phorbol myristate acetate plus ionomycin (PMA/IO)]. Participants were previously institutionalized (PI) youth (N = 45, 56 % female) who had spent their first years in institutional care (e.g., orphanages, baby homes) before being adopted into well-resourced homes (median age at adoption = 13 mos) and non-adopted comparisons (NA; N = 38, 55 % female). Their age range was 13.3-21.2 years (M = 16.3 years). This analysis followed up an earlier report on these youth (Reid et al., 2019a) that identified an increase in terminally differentiated CD8 + CD57 T cells among the PI relative to the NA youth. Cytokine levels in circulation were not highly correlated and thus examined separately. PI youth had higher circulating levels of Tumor Necrosis Factor-alpha (TNFα), but not Interleukin-1β (IL-1β) or Interleukin-6 (IL-6). Cytokine responses to in vitro activation within each stimulant condition were highly correlated and were thus combined to generate an index of the inflammatory reaction to each stimulant. Using Multivariate Analysis of Covariance, there was a highly significant multivariate effect of group, which was carried primarily by the PMA/IO condition, with PI youth exhibiting a larger inflammatory response than NA youth. Tests of mediation showed that both the early rearing effects on circulating TNFα and the composite inflammatory index of PMA/IO responsiveness were mediated in the statistical model by the percentage of CD8 + CD57+ TEMRA cells in circulation, a marker of replicative senescence in T cells. Sex differences were also found in circulating levels of IL-6 and TNFα, with males having higher levels than females.

Chronic hypoxaemia and gender status modulate adiponectin plasmatic level and its multimer proportion in severe COPD patients: new endotypic presentation?

BACKGROUND

Disease progression in COPD patient is associated to lung function decline, leading to a higher risk of hypoxaemia and associated comorbidities, notably cardiovascular diseases (CVD). Adiponectin (Ad) is an adipokine with cardio-protective properties. In COPD patients, conflicting results were previously reported regarding Ad plasmatic (Adpl) level, probably because COPD is a heterogeneous disease with multifactorial influence. Among these factors, gender and hypoxaemia could interact in a variety of ways with Ad pathway. Therefore, we postulated that these components could influence Adpl level and its multimers in COPD patients and contribute to the appearance of a distinct endotype associated to an altered CVD risk.

METHODS

One hundred COPD patients were recruited: 61 were men and 39 were women. Patients who were not severely hypoxemic were allocated to non-hypoxemic group which included 46 patients: 27 men and 19 women. Hypoxemic group included 54 patients: 34 men and 20 women. For all patients, Adpl level and proportion of its different forms were measured. Differences between groups were evaluated by Rank-Sum tests. The relationship between these measures and BMI, blood gas analysis (PaO2, PaCO2), or lung function (FEV1, FEV1/FVC, TLCO, TLC, RV) were evaluated by Pearson correlation analysis.

RESULTS

Despite similar age, BMI and obstruction severity, women had a higher TLC and RV (median: TLC = 105%; RV = 166%) than men (median: TLC = 87%; RV = 132%). Adpl level was higher in women (median = 11,152 ng/ml) than in men (median = 10,239 ng/ml) and was negatively associated with hyperinflation (R = - 0,43) and hypercapnia (R = - 0,42). The proportion of the most active forms of Ad (HMW) was increased in hypoxemic women (median = 10%) compared with non-hypoxemic women (median = 8%) but was not modulated in men.

CONCLUSION

COPD pathophysiology seemed to be different in hypoxemic women and was associated to Ad modulations. Hyperinflation and air-trapping in association with hypercapnia and hypoxaemia, could contribute to a modulation of Adpl level and of its HMW forms. These results suggest the development of a distinct endotypic presentation, based on gender.

The influence of sex, genotype, and dose on serum and hippocampal cytokine levels in juvenile mice developmentally exposed to a human-relevant mixture of polychlorinated biphenyls

Polychlorinated biphenyls (PCBs) are pervasive environmental contaminants implicated as risk factors for neurodevelopmental disorders (NDDs). Immune dysregulation is another NDD risk factor, and developmental PCB exposures are associated with early life immune dysregulation. Studies of the immunomodulatory effects of PCBs have focused on the higher-chlorinated congeners found in legacy commercial mixtures. Comparatively little is known about the immune effects of contemporary, lower-chlorinated PCBs. This is a critical data gap given recent reports that lower-chlorinated congeners comprise >70% of the total PCB burden in serum of pregnant women enrolled in the MARBLES study who are at increased risk for having a child with an NDD. To examine the influence of PCBs, sex, and genotype on cytokine levels, mice were exposed throughout gestation and lactation to a PCB mixture in the maternal diet, which was based on the 12 most abundant PCBs in sera from MARBLES subjects. Using multiplex array, cytokines were quantified in the serum and hippocampus of weanling mice expressing either a human gain-of-function mutation in ryanodine receptor 1 (T4826I mice), a human CGG premutation repeat expansion in the fragile X mental retardation gene 1 (CGG mice), or both mutations (DM mice). Congenic wildtype (WT) mice were used as controls. There were dose-dependent effects of PCB exposure on cytokine concentrations in the serum but not hippocampus. Differential effects of genotype were observed in the serum and hippocampus. Hippocampal cytokines were consistently elevated in T4826I mice and also in WT animals for some cytokines compared to CGG and DM mice, while serum cytokines were usually elevated in the mutant genotypes compared to the WT group. Males had elevated levels of 19 cytokines in the serum and 4 in the hippocampus compared to females, but there were also interactions between sex and genotype for 7 hippocampal cytokines. Only the chemokine CCL5 in the serum showed an interaction between PCB dose, genotype, and sex. Collectively, these findings indicate differential influences of PCB exposure and genotype on cytokine levels in serum and hippocampal tissue of weanling mice. These results suggest that developmental PCB exposure has chronic effects on baseline serum, but not hippocampal, cytokine levels in juvenile mice.

COVID-19 as an Acute Inflammatory Disease

The 2019 coronavirus disease (COVID-19) pandemic caused by the virus severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has created an unprecedented global crisis for the infrastructure sectors, including economic, political, healthcare, education, and research systems. Although over 90% of infected individuals are asymptomatic or manifest noncritical symptoms and will recover from the infection, those individuals presenting with critical symptoms are in urgent need of effective treatment options. Emerging data related to mechanism of severity and potential therapies for patients presenting with severe symptoms are scattered and therefore require a comprehensive analysis to focus research on developing effective therapeutics. A critical literature review suggests that the severity of SARS-CoV-2 infection is associated with dysregulation of inflammatory immune responses, which in turn inhibits the development of protective immunity to the infection. Therefore, the use of therapeutics that modulate inflammation without compromising the adaptive immune response could be the most effective therapeutic strategy.

COVID-19 and Individual Genetic Susceptibility/Receptivity: Role of ACE1/ACE2 Genes, Immunity, Inflammation and Coagulation. Might the Double X-chromosome in Females Be Protective against SARS-CoV-2 Compared to the Single X-Chromosome in Males?

In December 2019, a novel severe acute respiratory syndrome (SARS) from a new coronavirus (SARS-CoV-2) was recognized in the city of Wuhan, China. Rapidly, it became an epidemic in China and has now spread throughout the world reaching pandemic proportions. High mortality rates characterize SARS-CoV-2 disease (COVID-19), which mainly affects the elderly, causing unrestrained cytokines-storm and subsequent pulmonary shutdown, also suspected micro thromboembolism events. At the present time, no specific and dedicated treatments, nor approved vaccines, are available, though very promising data come from the use of anti-inflammatory, anti-malaria, and anti-coagulant drugs. In addition, it seems that males are more susceptible to SARS-CoV-2 than females, with males 65% more likely to die from the infection than females. Data from the World Health Organization (WHO) and Chinese scientists show that of all cases about 1.7% of women who contract the virus will die compared with 2.8% of men, and data from Hong Kong hospitals state that 32% of male and 15% of female COVID-19 patients required intensive care or died. On the other hand, the long-term fallout of coronavirus may be worse for women than for men due to social and psychosocial reasons. Regardless of sex- or gender-biased data obtained from WHO and those gathered from sometimes controversial scientific journals, some central points should be considered. Firstly, SARS-CoV-2 has a strong interaction with the human ACE2 receptor, which plays an essential role in cell entry together with transmembrane serine protease 2 (TMPRSS2); it is interesting to note that the ACE2 gene lays on the X-chromosome, thus allowing females to be potentially heterozygous and differently assorted compared to men who are definitely hemizygous. Secondly, the higher ACE2 expression rate in females, though controversial, might ascribe them the worst prognosis, in contrast with worldwide epidemiological data. Finally, several genes involved in inflammation are located on the X-chromosome, which also contains high number of immune-related genes responsible for innate and adaptive immune responses to infection. Other genes, out from the RAS-pathway, might directly or indirectly impact on the ACE1/ACE2 balance by influencing its main actors (e.g., ABO locus, SRY, SOX3, ADAM17). Unexpectedly, the higher levels of ACE2 or ACE1/ACE2 rebalancing might improve the outcome of COVID-19 in both sexes by reducing inflammation, thrombosis, and death. Moreover, X-heterozygous females might also activate a mosaic advantage and show more pronounced sex-related differences resulting in a sex dimorphism, further favoring them in counteracting the progression of the SARS-CoV-2 infection.

Enhanced Myeloid Leukocytes in Obese Children and Adolescents at Risk for Metabolic Impairment

Objective: We aimed to examine if myeloid leukocyte profiles are associated with metabolic impairment in children and adolescents with obesity, and if sex, age, or race influence this relationship. Methods: 282 children ages 8-17 were evaluated. Predictor measures were absolute neutrophil counts (ANC), absolute monocyte count, monocyte subtypes and C reactive protein (CRP). Outcome variables were waist circumference, fasting glucose and insulin, HOMA-IR, HbA1c (%) and lipid profiles. Pearson correlation coefficients were used to determine associations between predictor and outcome variables. Wilcoxon two-sample tests were used to evaluate differences by sex. Results: CRP (p < 0.0001), ANC (p < 0.0018), and classical monocytes (p = 0.05) were significantly higher in children with obesity. CRP, ANC and classical monocytes showed positive correlations with waist circumference, insulin, HOMA-IR and triglycerides. CRP was positively associated with ANC overall (p = 0.05). ANC demonstrated positive correlation with monocytes (p < 0.001). The associations between predictor and outcome variables were influenced by sex, race, and age. Conclusions: CRP and myeloid leukocyte populations, specifically classical monocytes and neutrophils associate with both body composition and metabolic parameters in children with obesity suggesting that these cells may play a critical role in metabolic impairment. Race, gender and age interactions between monocytes and metabolic parameters were significant.

Pubertal Status and Age are Differentially Associated with Inflammatory Biomarkers in Female and Male Adolescents

A better understanding of the maturational correlates of inflammatory activity during adolescence is needed to more appropriately study both normal and abnormal development. Inflammation is the immune system's first response to infection, injury, or psychological stress, and it has been shown to be elevated in individuals with both physical and psychological conditions. This study examined unique associations between (1) pubertal status and inflammatory biomarkers, and (2) age and inflammatory biomarkers, and whether these relationships differed by sex in a diverse sample of 155 adolescents (54.2% female, 45.8% male; M_age = 16.22) from a northeastern city in the US. A more advanced pubertal status was uniquely associated with lower levels of tumor necrosis factor alpha (TNF-α) and interleukin-8 (IL-8). Chronological age was uniquely associated with lower IL-8 levels. The association between pubertal status and C-reactive protein (CRP) levels differed by sex: more mature females had higher CRP, whereas pubertal status and CRP were not significantly associated in males. These findings highlight an important relation between pubertal development and inflammatory activity during adolescence.

Methanol extract of Cola nitida ameliorates inflammation and nociception in experimental animals

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Methanol extract Cola nitida possesses analgesic properties in mice.

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Methanol extract of Cola nitida showed anti-inflammatory activity.

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Methanol extract of cola nitida mediates its nociceptive action through cholinergic pathway.

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Opioid and beta adrenergic pathways do not mediate the analgesic potential of Cola nitida.

Methanol extract of Cola nitida (MECN) was evaluated for its anti-inflammatory and analgesic activities using rats and mice. Inflammatory activity of MECN was assessed by carrageenan-induced paw oedema while analgesic activity was evaluated by acetic acid –induced writhing and formalin paw lick test. Histological analyses of the paws were also carried out. There was evaluation of the mechanism(s) of action of MECN using naloxone, a blocker of opioid receptors; atropine, blocker of muscarinic receptors; and propranolol, blocker of beta adrenergic receptors. Findings from the study revealed that MECN has both anti-inflammatory and analgesic properties. These properties were found to be dose dependent with 200 mg/kg of MECN discovered to be the most potent dose. 200 mg/kg was able to cause statistically significant reduction in paw size (p < 0.001) when compared with the carrageenan group. Histological analysis revealed that rats treated with 200 mg/kg of MECN showed no inflammatory cells in the left paw compared to other groups treated with carrageenan. In the formalin test, the number of paw licking was significantly reduced by MECN at 50 mg/kg, 100 mg/kg and 200 mg/kg in both neurogenic and inflammatory pain responses (p < 0.001) even as 200 mg/kg showed the highest percentage inhibition of 98.17% while 100 mg/kg of aspirin showed percentage inhibition of 93.66%. In acetic acid-induced writhing test, 50 mg/kg, 100 mg/kg and 200 mg/kg of MECN produced significant inhibition of writhes when compared with control as highest inhibition is observed in mice that received 200 mg/kg which is similar to aspirin. Administration of propranolol and naloxone was unable to reverse the analgesic function of MECN. However, atropine administration blocked the analgesic function of MECN. This shows that MECN exhibits its analgesic property through cholinergic pathway and not opioid and adrenergic pathways. Phytochemical screening revealed that MECN contains flavonoids, steroids, saponins, tannins, anthraquinines, terpenoids, and alkanoids. These phytochemical contents may thus be responsible for its analgesic and anti-inflammatory properties.

Sex-differences in LPS-induced neonatal lung injury

Being of the male sex has been identified as a risk factor for multiple morbidities associated with preterm birth, including bronchopulmonary dysplasia (BPD). Exposure to inflammatory stress is a well-recognized risk factor for developing BPD. Whether there is a sex difference in pulmonary innate immune TLR4 signaling, lung injury and subsequent abnormal lung development is unknown. Neonatal (P0) male and female mice (ICR) were exposed to systemic LPS (5 mg/kg, IP) and innate immune signaling, and the transcriptional response were assessed (1 and 5 hours), along with lung development (P7). Male and female mice demonstrated a similar degree of impaired lung development with decreased radial alveolar counts, increased surface area, increased airspace area and increased mean linear intercept. We found no differences between male and female mice in the baseline pulmonary expression of key components of TLR4-NFκB signaling, or in the LPS-induced pulmonary expression of key mediators of neonatal lung injury. Finally, we found no difference in the kinetics of LPS-induced pulmonary NFκB activation between male and female mice. Together, these data support the conclusion that the innate immune response to early postnatal LPS exposure and resulting pulmonary sequelae is similar in male and female mice.

The Number of X Chromosomes Influences Inflammatory Cytokine Production Following Toll-Like Receptor Stimulation

Sex differences are observed in the evolution of numerous inflammatory conditions. Women exhibit better clinical courses compared to men in acute inflammatory processes, yet worse prognosis in several chronic inflammatory diseases. Inflammatory markers are significantly different between prepubertal boys and girls, whose sex steroid levels are very low, suggesting genetics play a role. To evaluate the potential influence of the X chromosome, we studied cytokine production and protein phosphorylation following Toll-like receptor (TLR) activation in whole blood and purified neutrophils and monocytes of healthy adults of both sexes as well as subjects with Klinefelter syndrome. We recorded higher levels of inflammatory cytokines in men compared to both women and patients with Klinefelter syndrome following whole blood stimulation. In purified monocytes, production of inflammatory cytokines was also higher in men compared to women, while Klinefelter subjects expressed the same pattern of cytokine production as males, in contrast with whole blood analyses. These differences remained after adjusting for sex steroid levels. Our study revealed higher cytokine inflammatory responses in men than women, yet also compared to subjects with Klinefelter syndrome, who carry two copies of the X chromosome, like women, and thus potentially benefit from the cellular mosaicism of X-linked genes.

Cytokine secretion responsiveness of lymphomonocytes following cortisol cell exposure: Sex differences

The stress hormone cortisol has been recognized as a coordinator of immune response. However, its different ability to modulate the release of inflammatory mediators in males and females has not been clarified yet. Indeed, the dissection of cortisol specific actions may be difficult due to the complex hormonal and physio-pathological individual status. Herein, the release of inflammatory mediators following increasing cortisol concentrations was investigated in an in vitro model of primary human male and female lymphomonocytes. The use of a defined cellular model to assess sex differences in inflammatory cytokine secretion could be useful to exclude the effects of divergent and fluctuating sex hormone levels occurring in vivo. Herein, the cells were challenged with cortisol concentrations resembling the plasma levels achieving in physiological and stressful conditions. The production of cytokines and other molecules involved in inflammatory process was determined. In basal conditions, male cells presented higher levels of some pro-inflammatory molecules (NF-kB and IDO-1 mRNAs, IL-6 and kynurenine) than female cells. Following cortisol exposure, the levels of the pro-inflammatory cytokines, IL-6 and IL-8, were increased in male cells. Conversely, in female cells IL-6 release was unchanged and IL-8 levels were decreased. Anti-inflammatory cytokines, IL-4 and IL-10, did not change in male cells and increased in female cells. Interestingly, kynurenine levels were higher in female cells than in male cells following cortisol stimulus. These results highlighted that cortisol differently affects male and female lymphomonocytes, shifting the cytokine release in favour of a pro-inflammatory pattern in male cells and an anti-inflammatory secretion profile in female cells, opening the way to study the influences of other stressful factors involved in the neurohumoral changes occurring in the response to stress conditions.

Sex differences influencing micro- and macrovascular endothelial phenotype in vitro

KEY POINTS

Endothelial dysfunction is an early hallmark of multiple disease states that also display sex differences with respect to age of onset, frequency and severity. Results of in vivo studies of basal and stimulated microvascular barrier function revealed sex differences that are difficult to ascribe to specific cells or environmental factors. The present study evaluated endothelial cells (EC) isolated from macro- and/or microvessels of reproductively mature rats under the controlled conditions of low-passage culture aiming to test the assumption that EC phenotype would be sex independent. The primary finding was that EC, regardless of where they are derived, retain a sex-bias in low-passage culture, independent of varying levels of reproductive hormones. The implications of the present study include the fallacy of expecting a universal set of mechanisms derived from study of EC from one sex and/or one vascular origin to apply uniformly to all EC under unstimulated conditions, and no less in disease.

ABSTRACT

Vascular endothelial cells (EC) are heterogeneous with respect to phenotype, reflecting at least the organ of origin, location within the vascular network and physical forces. As an independent influence on EC functions in health or aetiology, susceptibility, and progression of dysfunction in numerous disease states, sex has been largely ignored. The present study focussed on EC isolated from aorta (macrovascular) and skeletal muscle vessels (microvascular) of age-matched male and female rats under identical conditions of short-term (passage 4) culture. We tested the hypothesis that genomic sex would not influence endothelial growth, wound healing, morphology, lactate production, or messenger RNA and protein expression of key proteins (sex hormone receptors for androgen and oestrogens α and β; platelet endothelial cell adhesion molecule-1 and vascular endothelial cadherin mediating barrier function; α_v β₃ and N-cadherin influencing matrix interactions; intracellular adhesion molecule-1 and vascular cell adhesion molecule-1 mediating EC/white cell adhesion). The hypothesis was rejected because the EC origin (macro- vs. microvessel) and sex influenced multiple phenotypic characteristics. Statistical model analysis of EC growth demonstrated an hierarchy of variable importance, recapitulated for other phenotypic characteristics, with predictions assuming EC homogeneity < sex < vessel origin < sex and vessel origin. Furthermore, patterns of EC mRNA expression by vessel origin and by sex did not predict protein expression. Overall, the present study demonstrated that accurate assessment of sex-linked EC dysfunction first requires an understanding of EC function by position in the vascular tree and by sex. The results from a single EC tissue source/species/sex cannot provide universal insight into the mechanisms regulating in vivo endothelial function in health, and no less in disease.

Sexual dimorphism in bacterial infections

Background

Sex differences are important epidemiological factors that impact in the frequency and severity of infectious diseases. A clear sexual dimorphism in bacterial infections has been reported in both humans and animal models. Nevertheless, the molecular mechanisms involved in this gender bias are just starting to be elucidated. In the present article, we aim to review the available data in the literature that report bacterial infections presenting a clear sexual dimorphism, without considering behavioral and social factors.

Main body

The sexual dimorphism in bacterial infections has been mainly attributed to the differential levels of sex hormones between males and females, as well as to genetic factors. In general, males are more susceptible to gastrointestinal and respiratory bacterial diseases and sepsis, while females are more susceptible to genitourinary tract bacterial infections. However, these incidences depend on the population evaluated, animal model and the bacterial species. Female protection against bacterial infections and the associated complications is assumed to be due to the pro-inflammatory effect of estradiol, while male susceptibility to those infections is associated with the testosterone-mediated immune suppression, probably via their specific receptors. Recent studies indicate that the protective effect of estradiol depends on the estrogen receptor subtype and the specific tissue compartment involved in the bacterial insult, suggesting that tissue-specific expression of particular sex steroid receptors contributes to the susceptibility to bacterial infections. Furthermore, this gender bias also depends on the effects of sex hormones on specific bacterial species. Finally, since a large number of genes related to immune functions are located on the X chromosome, X-linked mosaicism confers a highly polymorphic gene expression program that allows women to respond with a more expanded immune repertoire as compared with men.

Conclusion

Notwithstanding there is increasing evidence that confirms the sexual dimorphism in certain bacterial infections and the molecular mechanisms associated, further studies are required to clarify conflicting data and to determine the role of specific hormone receptors involved in the gender bias of bacterial infections, as well as their potential as therapeutic targets.

Immune function? A missing link in the gender disparity in preterm neonatal outcomes

INTRODUCTION

In neonatology, males exhibit a more severe disease course and poorer prognosis in many pathological states when compared to females. Perinatal brain injury, respiratory morbidity, and sepsis, among other complications, preferentially affect males. Preterm neonates (born <37 weeks gestation) display a particularly marked sexual disparity in pathology, especially at the borders of viability. The sex biases in preterm neonatal outcomes and underlying multifactorial mechanisms have been incompletely explored. Sex-specific clinical phenomena may be partially explained by intrinsic differences in immune function. The distinct immune system of preterm neonates renders this patient population vulnerable, and it is increasingly important to consider biological sex in disease processes and to strive for improved outcomes for both sexes. Areas covered: We discuss the cellular responses and molecular intermediates in immune function which are strongly dependent on sex-specific factors such as the genetic and hormonal milieu of premature birth and consider novel findings in a clinical context. Expert commentary: The role of immune function in the manifestation of sex-specific disease manifestations and outcomes in preterm neonates is a critical prognostic variable. Further mechanistic elucidation will yield valuable translational and clinical information of disease processes in preterm neonates which may be harnessed for modulation.

Sex Differences in Inflammatory Response and Acid-Base Balance in Prepubertal Children with Severe Sepsis

PURPOSE AND METHODS

The severity and prognosis of various acute inflammatory conditions, such as sepsis, differ between males and females. The mechanisms underlying these sex differences probably involve both hormonal and genetic factors. In order to evaluate a possible genetic influence, we reviewed clinical signs and biological inflammatory markers of prepubertal children with severe sepsis admitted to the pediatric intensive care unit (PICU).

FINDINGS

A total of 142 prepubertal children, 66 girls and 76 boys, suffering from severe sepsis and admitted to the PICU were included. The survival rate demonstrated a tendency to be higher in females (P = 0.14). Maximum white blood cell count (23,800 cells/μL [15,110-34,600] in girls vs. 19,025 cells/μL [12,358-26,098] in boys, P = 0.02), neutrophil count (16,944 cells/μL [10,620-27,540] vs. 13,756 cells/μL [8410-20,110], P = 0.03), and C-reactive protein level (26.2 mg/dL [15.7-33.6] vs. 18.8 mg/dL [11.1-30.0], P = 0.04) were all significantly higher in girls. Girls also exhibited significantly longer fever duration (2 days [1-6] vs. 1 day [1-3] for the boys, P <0.01), lower pH on admission (7.32 [7.25-7.39] vs. 7.37 [7.31-7.43] P = 0.03), and lower base excess (-6 mEq/L [-10.7 to -0.8] vs. -2.3 mEq/L [-6.6 to -2.6], P <0.01), as well as lower bicarbonate levels (19.1 mEq/l [15.9-24.0] vs. 21.15 mEq/l [18.3-26.68], P = 0.04), when compared with the boys.

CONCLUSIONS

Our study revealed higher neutrophilic inflammation, as well as lower pH on admission, in girls with severe sepsis; associated with longer fever duration, which could contribute to better pathogen clearance. However, further studies are needed to demonstrate the link between acidosis and modulation of the immune response.

Human cells involved in atherosclerosis have a sex

The influence of sex has been largely described in cardiovascular diseases. Atherosclerosis is a complex process that involves many cell types such as vessel cells, immune cells and endothelial progenitor cells; however, many, if not all, studies do not report the sex of the cells. This review focuses on sex differences in human cells involved in the atherosclerotic process, emphasizing the role of sex hormones. Furthermore, we report sex differences and issues related to the processes that determine the fate of the cells such as apoptotic and autophagic mechanisms. The analysis of the data reveals that there are still many gaps in our knowledge regarding sex influences in atherosclerosis, largely for the cell types that have not been well studied, stressing the urgent need for a clear definition of experimental conditions and the inclusion of both sexes in preclinical studies.

Sex differences in immune responses

Males and females differ in their immunological responses to foreign and self-antigens and show distinctions in innate and adaptive immune responses. Certain immunological sex differences are present throughout life, whereas others are only apparent after puberty and before reproductive senescence, suggesting that both genes and hormones are involved. Furthermore, early environmental exposures influence the microbiome and have sex-dependent effects on immune function. Importantly, these sex-based immunological differences contribute to variations in the incidence of autoimmune diseases and malignancies, susceptibility to infectious diseases and responses to vaccines in males and females. Here, we discuss these differences and emphasize that sex is a biological variable that should be considered in immunological studies.

Impact of Cadmium Exposure on the Association between Lipopolysaccharide and Metabolic Syndrome

Cadmium (Cd) is an environmental contaminant that has a direct impact on the gut microbiome. Perturbations in the gut microbiome have been linked to metabolic disorders associated with inflammation generated by lipopolysaccharide (LPS). We investigated the impact of Cd on the association between LPS and metabolic syndrome. The study population consisted of 200 apparently healthy subjects (30–64 years of age; 96 men, 104 women). Serum LPS and blood Cd concentrations were measured by ELISA and graphite furnace-atomic absorption spectrophotometry (GF-AAS), respectively. The highest LPS quartile was associated with a greater prevalence of metabolic syndrome in men. There was a significant association between LPS activity and metabolic syndrome in men with blood Cd concentrations higher than the 50th percentile (OR = 3.05, 95% CI = 1.39–6.70); however, this relationship was not significant in men with blood Cd concentrations lower than the 50th percentile. The results of this study provide evidence for a strong association between high LPS activity and the prevalence of metabolic syndrome in men with relatively high blood Cd concentrations. Therefore, exposure to Cd may potentiate the association between LPS and metabolic syndrome in men.

Thyroid autoimmunity as a window to autoimmunity: An explanation for sex differences in the prevalence of thyroid autoimmunity

Autoimmune thyroid diseases (AITDs), predominately Graves׳ disease and Hashimoto׳s thyroiditis, comprise the most common autoimmune diseases in humans. Both have the production of anti-thyroid antibody as an important aspect and both are much more prevalent in females, being at least 10 times more common than in males. Using these two clues, a hypothesis for the initiation of thyroid autoimmunity is proposed that helps to make the case that the thyroid is one of the most sensitive sites for autoimmunity and helps account for the prevalence and the observed sex differences in AITDs and associated diseases, such as type 1 diabetes and Latent Autoimmune Diabetes in Adults (LADA). The primary mechanisms proposed involve the underlying state of inflammation as a result of the adipokines, especially leptin, TNF-α, and IL-6, and the receptors able to recognize pathogen-associated molecular patterns (PAMP׳s) and damage-associated molecular patterns (DAMP׳s) through Toll-like receptors (TLR) and others receptors present on thyrocytes. The adipokines are produced by adipose tissue, but have hormone-like and immune modulating properties. As the levels of leptin are significantly higher in females, an explanation for the sex difference in thyroid autoimmunity emerges. The ability of the thyrocytes to participate in innate immunity through the TLR provides an adjuvant-like signal and allows for the action of other agents, such as environmental factors, viruses, bacteria, and even stress to provide the initiation step to break tolerance to thyroid self-antigens. Seeing the thyroid as one of the most sensitive sites for autoimmunity, means that for many autoimmune disorders, if autoimmunity is present, it is likely to also be present in the thyroid - and that that condition in the thyroid was probably earlier. The evidence is seen in multiple autoimmune syndrome.

Probiotics and vitamin C for the prevention of respiratory tract infections in children attending preschool: a randomised controlled pilot study

Background:

This pilot study investigates the efficacy of a probiotic consortium (Lab4) in combination with vitamin C on the prevention of respiratory tract infections in children attending preschool facilities.

Subjects/methods:

In a double-blind, randomised, placebo-controlled pilot study with children aged 3–6 years, 57 received 1.25 × 10¹⁰ colony-forming units of Lactobacillus acidophilus CUL21 (NCIMB 30156), Lactobacillus acidophilus CUL60 (NCIMB 30157), Bifidobacterium bifidum CUL20 (NCIMB 30153) and Bifidobacterium animalis subsp. lactis CUL34 (NCIMB 30172) plus 50 mg vitamin C or a placebo daily for 6 months.

Results:

Significant reductions in the incidence rate of upper respiratory tract infection (URTI; 33%, P=0.002), the number of days with URTI symptoms (mean difference: −21.0, 95% confidence interval (CI):−35.9, −6.0, P=0.006) and the incidence rate of absence from preschool (30%, P=0.007) were observed in the active group compared with the placebo. The number of days of use of antibiotics, painkillers, cough medicine or nasal sprays was lower in the active group and reached significance for use of cough medicine (mean difference: −6.6, 95% CI: −12.9, −0.3, P=0.040). No significant differences were observed in the incidence rate ratio or duration of lower respiratory tract infection or in the levels of plasma cytokines, salivary immunoglobulin A or urinary metabolites.

Conclusions:

Supplementation with a probiotic/vitamin C combination may be beneficial in the prevention and management of URTIs.

Adiposity, aerobic fitness, muscle fitness, and markers of inflammation in children

PURPOSE

The purpose of this study was to describe levels of inflammation markers in Norwegian children and to examine the associations of adiposity, aerobic fitness, and muscle fitness with markers of inflammation.

METHODS

In 2005-2006, 1467 nine-year-olds were randomly selected from all regions in Norway. The participation rate was 89%. The inflammatory markers evaluated included C-reactive protein (CRP), leptin, adiponectin, plasminogen activator inhibitor-1, tumor necrosis factor-α, hepatocyte growth factor, resistin, and interleukin-6. We assessed muscular strength by measuring explosive, isometric, and endurance strength. Aerobic fitness was measured directly during a maximal cycle ergometer test. Adiposity was expressed as waist circumference (WC).

RESULTS

The girls had significantly higher levels of CRP, leptin, adiponectin, and resistin and lower levels of tumor necrosis factor-α compared with the boys. We observed a graded association of CRP and leptin levels across quintiles of WC, aerobic fitness, and muscle fitness (P ≤ 0.001 for all participants). The regression analyses revealed that WC, aerobic fitness, and muscle fitness were independently associated with the CRP (WC β = 0.158, P < 0.001; aerobic fitness β = -0.190, P < 0.001; muscle fitness β = -0.122, P < 0.002) after adjustments for sex, age, Tanner pubertal stage, and the other independent variables. The same pattern was observed for leptin levels (WC β = 0.406, P < 0.001; aerobic fitness β = -0.298, P < 0.001; muscle fitness β = -0.064, P < 0.036).

CONCLUSIONS

These data represent a reference material with respect to inflammatory markers. Our results show that adiposity, aerobic fitness, and muscle fitness were independently associated with the CRP and leptin levels.

Sex and inflammation in respiratory diseases: a clinical viewpoint

This review discusses sex differences in the prognosis of acute or chronic inflammatory diseases. The consequences of severe inflammation vary in relation to sex, depending on illness duration. In the majority of acute diseases, males present higher mortality rates, whereas continuous chronic inflammation associated with tissue damage is more deleterious in females. The recruitment of cells, along with its clinical expression, is more significant in females, as reflected by higher inflammatory markers. Given that estrogens or androgens are known to modulate inflammation, their different levels in males and females cannot account for the sexual dimorphism observed in humans and animals from birth to death with regard to inflammation. Numerous studies evaluated receptors, cytokine production, and clinical outcomes in both animals and humans, revealing that estrogens clearly modulate the immune response, but the results are contradictory and difficult to link to hormone concentrations. Even in prepubescent children, the presentation of acute pneumonia or chronic diseases mimics the adult pattern. Several genes located on the X chromosome have been shown to encode molecules involved in inflammation. Moreover, 10% to 15% of the genes from silenced X chromosome may escape inhibition. Females are also a mosaic of cells with genes from either paternal or maternal X chromosome. Therefore, polymorphism of X-linked genes would result in the presence of two cell populations with distinct regulatory arsenals, providing females with greater diversity to fight against infectious challenges, in comparison with the uniform cell populations in hemizygous males. The similarities observed between males and Turner syndrome patients using an endotoxin stimulation model support the difference in gene expression between monosomy and disomy for the X chromosome. Considering the enhanced inflammation in females, cytokine production may be assumed to be higher in females than males. Even if all results are not clear-cut, nonetheless, many studies have reported higher cytokine levels in both male humans and animals than in females. High IL-6 levels in males correlated with poorer prognosis and shorter longevity. A sound understanding of the basic regulatory mechanisms responsible for these gender differences may lead to new therapeutic targets.

Gender difference in genetic association between IL1A variant and early lumbar disc degeneration: a three-year follow-up

OBJECTIVE

The purpose of the present study was to analyze the associations between specific genetic markers and early disc degeneration (DD) or early disc degeneration progression (DDP) defined by magnetic resonance imaging (MRI).

METHODS

We selected eleven of the most promising single nucleotide polymorphisms (SNP) and compared the distributions of these genetic markers between groups defined by MRI in a Danish adolescent population (N=166) over a three-year follow-up period.

RESULTS

We observed a ten-fold higher annual incidence of endplate changes than previously reported in adults. The gender difference in IL1A rs1800587 association with DD remained significant and another association with DDP emerged in follow-up assessment. Among girls, the rs1800587 T-allele was associated both with DD (OR 2.82 [95% CI 1.29-6.16]) and with DDP (OR 2.45 [95% CI 1.03-5.82]). Among boys, the IL6 rs1800795 genotype G/C was protective in both DD (OR 0.26 [95% CI 0.09-0.72]) and DDP (OR 0.32 [95% CI 0.12-0.88]) with the IL6 rs1800797 genotype G/A was associated with a decreased likelihood of DD (OR 0.27 [95% CI 0.10-0.77]). Gender-genotype interactions were significant for polymorphisms in both IL1A and IL6. Correction for multiple testing weakened the associations for IL6 polymorphisms.

CONCLUSION

We conclude that gender specific effects in lumbar disc degeneration and its progression are possible. However, further evaluations in larger populations are needed. Our results provide some support to the hypothesis that early disc degeneration is an especially important phase in the cascade of degenerative disc disease.

Identifying predictors of interferon-γ release assay results in pediatric latent tuberculosis: a protective role of bacillus Calmette-Guerin?: a pTB-NET collaborative study

RATIONALE

Interferon-γ (IFN-γ) release assays are widely used to diagnose latent infection with Mycobacterium tuberculosis in adults, but their performance in children remains incompletely evaluated to date.

OBJECTIVES

To investigate factors influencing results of IFN-γ release assays in children using a large European data set.

METHODS

The Pediatric Tuberculosis Network European Trials group pooled and analyzed data from five sites across Europe comprising 1,128 children who were all investigated for latent tuberculosis infection by tuberculin skin test and at least one IFN-γ release assay. Multivariate analyses examined age, bacillus Calmette-Guérin (BCG) vaccination status, and sex as predictor variables of results. Subgroup analyses included children who were household contacts.

MEASUREMENTS AND MAIN RESULTS

A total of 1,093 children had a QuantiFERON-TB Gold In-Tube assay and 382 had a T-SPOT.TB IFN-γ release assay. Age was positively correlated with a positive blood result (QuantiFERON-TB Gold In-Tube: odds ratio [OR], 1.08 per year increasing age [P < 0.0001]; T-SPOT.TB: OR, 1.14 per year increasing age [P < 0.001]). A positive QuantiFERON-TB Gold In-Tube result was shown by 5.5% of children with a tuberculin skin test result less than 5 mm, by 14.8% if less than 10 mm, and by 20.2% if less than 15 mm. Prior BCG vaccination was associated with a negative IFN-γ release assay result (QuantiFERON-TB Gold In-Tube: OR, 0.41 [P < 0.001]; T-SPOT.TB: OR, 0.41 [P < 0.001]). Young age was a predictor of indeterminate IFN-γ release assay results, but indeterminate rates were low (3.6% in children < 5 yr, 1% in children > 5 yr).

CONCLUSIONS

Our data show that BCG vaccination may be effective in protecting children against Mycobacterium tuberculosis infection. To restrict use of IFN-γ release assays to children with positive skin tests risks underestimating latent infection.

Host and environmental factors influencing respiratory secretion of pro-wheezing biomarkers in preterm children

Cytokines are actively secreted by the respiratory mucosa of preterm children and participate in the pathogenesis of wheezing. This study aimed to identify the factors that could potentially influence respiratory secretion of cytokines in these children. A nasopharyngeal aspirate (NPA) was collected from 77 preterm children 1 yr after birth. NPAs from 14 healthy, 1-yr-old term children were collected in parallel. 27 cytokines were measured in the NPAs using a multiplex assay. Multivariate stepwise regression analysis with Bonferroni correction evidenced that the variable [daycare attendance] was associated with higher levels of [monocyte chemoattractant protein-1 (MCP-1), IL-6, vascular endothelial growth factor (VEGF), IL-1β, IL-10, tumor necrosis factor (TNF)-α]; [male sex] with higher levels of (MCP-1, VEGF, and IL-1β); [smokers at home] was associated with higher levels of MCP-1 (p < 0.0013). In turn, [prophylaxis with palivizumab] was associated with lower levels of (IL-6, IL-7) (p < 0.0013). All these mediators participate in the pathogenesis of asthma and recurrent wheezing. Preterm children secreted higher levels of chemokines (interferon-gamma inducible protein-10, macrophage inflammatory protein-1α, Eotaxin, MCP-1), growth factors (platelet-derived growth factor-bb, VEGF, fibroblast growth factor-basic, granulocyte macrophage colony-stimulating factor), Th1 (IL12, interferon-γ), Th2 (IL-9, IL-13), Th17 (IL-6, IL-17) cytokines, and immunomodulatory mediators (IL1RA and granulocyte colony-stimulating factor) than term children. In conclusion, we have identified for the first time a group of individual and environmental factors influencing respiratory secretion of cytokines in preterm children at the long term after birth. To know these factors could help to prevent the instauration of conditions linked to the appearance of chronic respiratory diseases such as wheezing or asthma.