Leptin as a Biomarker of Stress: A Systematic Review and Meta-Analysis

Body mass, neuro-hormonal stress processing, and disease activity in lean to obese people with multiple sclerosis

Overweight and obesity can worsen disease activity in multiple sclerosis (MS). Although psychobiological stress processing is increasingly recognized as important obesity factor that is tightly connected to proinflammatory metabolic hormones and cytokines, its role for MS obesity remains unexplored. Consequently, we investigated the interplay between body mass index (BMI), neural stress processing (functional connectivity, FC), and immuno-hormonal stress parameters (salivary cortisol and T cell glucocorticoid [GC] sensitivity) in 57 people with MS (six obese, 19 over-, 28 normal-, and four underweight; 37 females, 46.4 ± 10.6 years) using an Arterial-Spin-Labeling MRI task comprising a rest and stress stage, along with quantitative PCR. Our findings revealed significant positive connections between BMI and MS disease activity (i.e., higher BMI was accompanied by higher relapse rate). BMI was positively linked to right supramarginal gyrus and anterior insula FC during rest and negatively to right superior parietal lobule and cerebellum FC during stress. BMI showed associations with GC functioning, with higher BMI associated with lower CD8+ FKBP4 expression and higher CD8+ FKBP5 expression on T cells. Finally, the expression of CD8+ FKBP4 positively correlated with the FC of right supramarginal gyrus and left superior parietal lobule during rest. Overall, our study provides evidence that body mass is tied to neuro-hormonal stress processing in people with MS. The observed pattern of associations between BMI, neural networks, and GC functioning suggests partial overlap between neuro-hormonal and neural-body mass networks. Ultimately, the study underscores the clinical importance of understanding multi-system crosstalk in MS obesity.

The effects of sleep disruption on metabolism, hunger, and satiety, and the influence of psychosocial stress and exercise: A narrative review

Sleep deficiency is a ubiquitous phenomenon among Americans. In fact, in the United States, ∼78% of teens and 35% of adults currently get less sleep than recommended for their age-group, and the quality of sleep appears to be getting worse for many. The consequences of sleep disruption manifest in a myriad of ways, including insulin resistance and disrupted nutrient metabolism, dysregulation of hunger and satiety, and potentially increased body weight and adiposity. Consequently, inadequate sleep is related to an increased risk of various cardiometabolic diseases, including obesity, diabetes, and heart disease. Exercise has the potential to be an effective therapeutic to counteract the deleterious effects of sleep disruption listed above, whereas chronic psychosocial stress may causally promote sleep disruption and cardiometabolic risk. Here, we provide a narrative review of the current evidence on the consequences of short sleep duration and poor sleep quality on substrate metabolism, circulating appetite hormones, hunger and satiety, and weight gain. Secondly, we provide a brief overview of chronic psychosocial stress and its impact on sleep and metabolic health. Finally, we summarise the current evidence regarding the ability of exercise to counteract the adverse metabolic health effects of sleep disruption. Throughout the review, we highlight areas where additional interrogation and future exploration are necessary.

The Impact of Chronic Stress Related to COVID-19 on Eating Behaviors and the Risk of Obesity in Children and Adolescents

During the COVID-19 pandemic, an increase in the incidence of overweight and obesity in children was observed. It appears that unhealthy food choices, an unbalanced diet, and a sedentary lifestyle, as well as experiencing stress related to the pandemic, may be contributing to this disturbing trend. Chronic stress is a significant factor contributing to eating disorders and obesity in youngsters, involving medical, molecular, and psychological elements. Individuals under chronic stress often focus on appearance and weight, leading to negative body image and disrupted relationships with food, resulting in unhealthy eating behaviors. Chronic stress also impacts hormonal balance, reducing the satiety hormone leptin and elevating the appetite-stimulating hormone ghrelin, fostering increased hunger and uncontrolled snacking. Two systems, the hypothalamic-pituitary-adrenal axis and the sympathetic system with the adrenal medulla, are activated in response to stress, causing impaired secretion of noradrenaline and cortisol. Stress-related obesity mechanisms encompass oxidative stress, neuroinflammation, insulin resistance, and neurohormonal and neurotransmission disorders. Stress induces insulin resistance, elevating obesity risk by disrupting blood sugar regulation and fat storage. Stress also affects the gut microbiome, potentially influencing chronic inflammation and metabolic processes linked to obesity. In conclusion, chronic stress is a multifaceted risk factor for eating disorders and obesity in children, necessitating a comprehensive understanding of effective preventive and intervention strategies amid the escalating prevalence of childhood overweight and obesity.

On the origins of sleep disordered breathing, cardiorespiratory and metabolic dysfunction: which came first, the chicken or the egg?

Sleep disordered breathing (SDB) is a complex, sex specific and highly heterogeneous group of respiratory disorders. Nevertheless, sleep fragmentation and repeated fluctuations of arterial blood gases for several hours per night are at the core of the problem; together, they impose significant stress to the organism with deleterious consequences on physical and mental health. SDB increases the risk of obesity, diabetes, depression and anxiety disorders; however, the same health issues are risk factors for SDB. So, which came first, the chicken or the egg? What causes the appearance of the first significant apnoeic events during sleep? These are important questions because although moderate to severe SDB affects ∼500 million adults globally, we still have a poor understanding of the origins of the disease, and the main treatments (and animal models) focus on the symptoms rather than the cause. Because obesity, metabolic dysfunction and stress-related neurological disorders generally appear progressively, we discuss how the development of these diseases can lead to specific anatomical and non-anatomical traits of SDB in males and females while considering the impacts of sex steroids. In light of the growing evidence indicating that the carotid bodies are important sensors of key metabolic and endocrine signals associated with stress and dysmetabolism, we propose that these organs play a key role in the process.

JAK-STAT signaling in inflammation and stress-related diseases: implications for therapeutic interventions

The Janus kinase-signal transducer and transcription activator pathway (JAK-STAT) serves as a cornerstone in cellular signaling, regulating physiological and pathological processes such as inflammation and stress. Dysregulation in this pathway can lead to severe immunodeficiencies and malignancies, and its role extends to neurotransduction and pro-inflammatory signaling mechanisms. Although JAK inhibitors (Jakinibs) have successfully treated immunological and inflammatory disorders, their application has generally been limited to diseases with similar pathogenic features. Despite the modest expression of JAK-STAT in the CNS, it is crucial for functions in the cortex, hippocampus, and cerebellum, making it relevant in conditions like Parkinson's disease and other neuroinflammatory disorders. Furthermore, the influence of the pathway on serotonin receptors and phospholipase C has implications for stress and mood disorders. This review expands the understanding of JAK-STAT, moving beyond traditional immunological contexts to explore its role in stress-related disorders and CNS function. Recent findings, such as the effectiveness of Jakinibs in chronic conditions such as rheumatoid arthritis, expand their therapeutic applicability. Advances in isoform-specific inhibitors, including filgotinib and upadacitinib, promise greater specificity with fewer off-target effects. Combination therapies, involving Jakinibs and monoclonal antibodies, aiming to enhance therapeutic specificity and efficacy also give great hope. Overall, this review bridges the gap between basic science and clinical application, elucidating the complex influence of the JAK-STAT pathway on human health and guiding future interventions.

The Levels of Leptin, Cystatin C, Neuropilin-1 and Tau Protein in Relation to Dietary Habits in Patients with Alzheimer's Disease

Alzheimer's disease (AD) is the most common form of dementia in older people. Its prevalence is expected to increase, and therefore it poses a serious challenge to the healthcare system. The aim of the study was to assess the concentration of leptin, cystatin C, neuropilin-1 and tau protein, as well as the influence of dietary habits on these parameters, in a group of AD patients (n = 110) compared to 60 healthy people (n = 60). It has been shown that AD patients, compared to healthy people, are characterized by significantly higher median concentrations of leptin (9.97 vs. 3.08), cystatin c (1.53 vs. 0.56) and tau protein (8.46 vs. 4.19), but significantly lower median neuropilin-1 (69.94 vs. 167.28). Multiple regression analyses showed that leptin levels could be explained by dietary habits in 27%, cystatin C in 51%, neuropilin-1 in 41% and tau protein in 25% of cases. Modification of eating habits may contribute to improving the values of the discussed parameters.

Obesity, Adipokines, and Chronic and Persistent Pain in Rheumatoid Arthritis

We aimed to determine whether adipokines are associated with pain and polysymptomatic distress in patients with rheumatoid arthritis (RA) over time in a large patient registry. The cohort study was conducted in a subset of Forward; a patient-based multi-disease, multipurpose rheumatic disease registry with patients enrolled from community-based rheumatology practices across the U.S. Adipokines (adiponectin, leptin, and fibroblast growth factor[FGF]-21) were measured on stored serum as part of a multi-analyte panel. Body mass index (BMI), pain, polysymptomatic distress, and other patient-reported outcomes (PROs) were reported on biannual questionnaires. Linear regression was used to evaluate independent associations between BMI, adipokines, and PROs. Cox proportional hazards models evaluated independent associations between adipokines and clinically meaningful changes in pain over time (change in numerical rating>1.1 [range 0-10], sustained over 1 year). Among 645 patients included in these analyses, there were significant differences in RA characteristics, comorbidity, PROs, and adipokines across obesity categories. Of note, severely obese patients were more likely to experience greater pain, polysymptomatic distress, and fatigue. Patients with higher FGF-21 levels had higher pain and polysymptomatic stress at baseline, were more likely to use opioids, and were more likely to have sustained worsening pain over time [HR (per 1 SD) (95% CI): 1.22 (1.02,1.46) P = .03] independent of BMI. Obesity and elevated levels of FGF-21 are associated with pain and polysymptomatic distress in RA. Elevated FGF-21 levels may help identify those at risk of worsening pain trajectories over time, independent of BMI. PERSPECTIVE: This study characterizes the relationship between severe obesity and pain and polysymptomatic distress in patients with rheumatoid arthritis and demonstrates that the adipocytokine fibroblast growth factor-21 is independently associated with pain and predicts a worsening trajectory over time. Further mechanistic studies are needed.

Influence of COVID-19 on Stress at Work During the First Wave of the Pandemic Among Emergency Health Care Workers

OBJECTIVES

For more than 2 years, coronavirus disease (COVID-19) has forced worldwide health care systems to adapt their daily practice. These adaptations add to the already stressful demands of providing timely medical care in an overcrowded health care system. Specifically, the COVID-19 pandemic added stress to an already overwhelmed emergency and critical care health care workers (HCWs) on the front lines during the first wave of the pandemic.This study assessed comparative subjective and objective stress among frontline HCWs using a visual analog scale and biometric data, specifically heart rate variability (HRV).

METHODS

This is a prospective, observational study using surveys and heart rate monitoring among HCWs who work in 3 frontline health care units (emergency department, mobile intensive care unit, and intensive care unit) in the University Hospital of Clermont-Ferrand, France. Two sessions were performed: 1 during the first wave of the pandemic (April 10 to May 10, 2020) and 1 after the first wave of the pandemic (June 10 to July 15, 2020).The primary outcome is the difference in stress levels between the 2 time points. Secondary objectives were the impact of overcrowding, sociodemographics, and other variables on stress levels. We also assessed the correlation between subjective and objective stress levels.

RESULTS

Among 199 HCWs, 98 participated in biometric monitoring, 84 had biometric and survey data, and 12 with only biometric data. Subjective stress was higher during the second time point compared to the first (4.39 ± 2.11 vs 3.16 ± 2.34, P = 0.23). There were higher objective stress levels with a decrease in HRV between the first and the second time points. Furthermore, we found higher patient volumes as a source of stress during the second time point. We did not find any significant correlation between subjective and objective stress levels.

CONCLUSION

HCWs had higher stress levels between the 2 waves of the pandemic. Overcrowding in the emergency department is associated with higher stress levels. We did not find any correlation between subjective and objective stress among intensive care and emergency HCWs during the first wave of the pandemic.

Placenta DNA methylation levels of the promoter region of the leptin receptor gene are associated with infant cortisol

The intrauterine environment and early life stress regulation are widely recognized as an early foundation for lifelong physical and mental health. Methylation of CpG sites in the placenta represents an epigenetic modification that can potentially affect placental function, influence fetal development, and ultimately impact the health of offspring by programming the hypothalamic-pituitary-adrenal (HPA) axis stress response during prenatal development. Leptin, an adipokine produced by the placenta, is essential for energy homeostasis. It is also epigenetically regulated by promoter DNA methylation. Mounting evidence suggests that leptin also affects the stress response system. Though heterogeneity in the early stress response system may influence life-long mental and physical health, few studies explicitly examine the heterogeneity in the newborn stress response system. Less is known about leptin's association with the human hypothalamic-pituitary-adrenocortical (HPA) axis early in life. This study sought to serve as a proof of concept study investigating the relationship between newborn cortisol output trajectories and placental leptin DNA methylation in 117 healthy newborns from socioeconomically and racially- and ethnically-diverse families. We characterized heterogeneity in newborn cortisol output during the NICU Network Neurobehavioral Scales exam in the first week of life with latent growth mixture models. We then evaluated whether leptin promoter (LEP) methylation in placental samples was associated with newborn cortisol trajectories. Our findings suggest that increased placental LEP methylation, which corresponds to decreased leptin production, is associated with infant cortisol trajectories marked by increased cortisol output in the NNNS exam. These results provide important insights into the role of placental leptin DNA methylation in human newborn HPA axis development and subsequent developmental origins of health and disease processes.

Effects of Exogenous Glucocorticoid Infusion on Appetitic Center Development in Postnatal Dairy Bull Calves

The objective of this study was to determine the effects of exogenous glucocorticoid administration on leptin concentrations and brain development markers, such as protein and hypothalamic gene expression, in dairy bull calves. Within 4 h of parturition, Holstein bulls were intravenously infused with either a low cortisol dose (LC; n = 9, 3.5 µg/kg of body weight (BW)), high cortisol dose (HC; n = 9, 7.0 µg/kg BW), or control (CON; n = 9, saline) dose, with a 2nd infusion 24 h postpartum. Jugular blood was collected prior to infusion and daily until the calves were euthanized (day 5). Cerebrospinal fluid (CSF) from the third ventricle and adipose (omental, perirenal, and mesenteric) and hypothalamic tissue were collected. The blood and CSF samples were analyzed for leptin concentrations. The data were analyzed using SAS. Serum (p = 0.013) and CSF (p = 0.005) leptin concentrations in HC- and LC-treated calves were decreased compared with CON-treated calves. Leptin protein expression was decreased (p < 0.044) in perirenal and omental adipose tissue of LC-treated calves compared with CON-treated calves. Gene abundance of brain-derived neurotrophic factor and fibroblast growth factors 1 and 2 were decreased (p < 0.006) in HC- and LC-treated calves compared with CON-treated calves. In summary, cortisol administered to dairy bull calves reduced leptin concentrations, decreased leptin protein expression in perirenal and omental adipose tissue, and altered gene expression in hypothalamic tissue.

Impact of Two Types of Exercise Interventions on Leptin and Omentin Concentrations and Indicators of Lipid and Carbohydrate Metabolism in Males with Metabolic Syndrome

Leptin (LEP) and omentin (OMEN) are proteins whose concentrations change with the development of the metabolic syndrome (MetS). There are few intervention studies using various forms of physical activity in people with MetS that aim to determine the impact of physical exercise on the fluctuations of the presented hormones, and their results are contradictory. The present study aimed to examine the effect of two types of exercise intervention on LEP and OMEN concentrations and indicators of lipid and carbohydrate metabolism in males with MetS. The study included 62 males with MetS (age 36.6 ± 6.9 years, body mass 110.31 ± 17.37 kg), randomly allocated to EG1, the examined group with aerobic training (n = 21); EG2, the examined group with combined aerobic and resistance training (n = 21), both for 12 weeks, and the control group (CG) without interventions (n = 20). Anthropometric measurements, body composition (body fat [BF], android body fat [ANDR]), as well as a biochemical blood analysis (omentin [OMEN], leptin [LEP], quantitative insulin sensitivity check index [QUICKI], high-density lipoprotein cholesterol [HDL-C] and nonHDL-C) were performed at baseline, and at 6 and 12 weeks of interventions and after 4 weeks after ending intervention (follow-up). Intergroup and intragroup comparisons were performed. In the intervention groups EG1 and EG2, a decrease in BF was observed as well as an improvement in carbohydrate metabolism parameters. In the EG1 group, the level of ANDR was reduced. In EG2 a decrease in LEP concentration between measurements was confirmed. However, no significant changes were found in the concentration of OMEN in any groups. Combined aerobic and resistance exercises led to a higher reduction of LEP concentration than applying only aerobic training in males with MetS.

A genetic variant of fatty acid amide hydrolase (FAAH) exacerbates hormone-mediated orexigenic feeding in mice

Fatty acid amide hydrolase (FAAH) degrades the endocannabinoid anandamide. A polymorphism in FAAH (FAAH C385A) reduces FAAH expression, increases anandamide levels, and increases the risk of obesity. Nevertheless, some studies have found no association between FAAH C385A and obesity. We investigated whether the environmental context governs the impact of FAAH C385A on metabolic outcomes. Using a C385A knock-in mouse model, we found that FAAH A/A mice are more susceptible to glucocorticoid-induced hyperphagia, weight gain, and activation of hypothalamic AMP-activated protein kinase (AMPK). AMPK inhibition occluded the amplified hyperphagic response to glucocorticoids in FAAH A/A mice. FAAH knockdown exclusively in agouti-related protein (AgRP) neurons mimicked the exaggerated feeding response of FAAH A/A mice to glucocorticoids. FAAH A/A mice likewise presented exaggerated orexigenic responses to ghrelin, while FAAH knockdown in AgRP neurons blunted leptin anorectic responses. Together, the FAAH A/A genotype amplifies orexigenic responses and decreases anorexigenic responses, providing a putative mechanism explaining the diverging human findings.

The Impact of Job-Demand-Control-Support on Leptin and Ghrelin as Biomarkers of Stress in Emergency Healthcare Workers

Despite the available literature on the consequences of night shiftwork on stress and food intake, its impact on leptin and ghrelin has never been studied. We previously demonstrated that leptin and ghrelin were biomarkers related to stress, and acute stress-induced a decrease in leptin levels and an increase in ghrelin levels. We performed a prospective observational study to assess the influence of night work, nutrition, and stress on the levels of ghrelin and leptin among emergency healthcare workers (HCWs). We took salivary samples at the beginning of a day shift and/or at the end of a night shift. We also monitored stress using the job demand-control-support model of Karasek. We recorded 24-h food intake during the day shift and the consecutive night shift and during night work and the day before. We included 161 emergency HCWs. Emergency HCWs had a tendency for decreased levels of leptin following the night shift compared to before the dayshift (p = 0.067). Furthermore, the main factors explaining the decrease in leptin levels were an increase in job-demand (coefficient -54.1, 95 CI -99.0 to -0.92) and a decrease in job control (-24.9, -49.5 to -0.29). Despite no significant changes in ghrelin levels between shifts, social support was the main factor explaining the increase in ghrelin (6.12, 0.74 to 11.5). Food intake (kcal) also had a negative impact on leptin levels, in addition to age. Ghrelin levels also decreased with body mass index, while age had the opposite effect. In conclusion, we confirmed that ghrelin and leptin as biomarkers of stress were directly linked to the job demand-control-support model of Karasek, when the main cofounders were considered.

Cytokine database of stress and metabolic disorders (CdoSM): a connecting link between stress and cardiovascular disease, hypertension, diabetes and obesity

The risk of metabolic diseases is greatly increased by both chronic and acute stress. Irrespective of the cause, chronic or acute stress has the capacity to alter an individual's cytokine profile. For instance, it has been observed that stress significantly increased concentrations of IL 1 beta, IL 6 and TNF alpha. Alteration in cytokine profiles increase the likelihood of dysregulated metabolism, which subsequently acts as a driving force in the development of disorders, such as cardiovascular disease (CVD), hypertension, diabetes and obesity. Considering the dynamic and versatile role of cytokines in health and disease, an in-depth computational analysis (qualitative and quantitative) was performed to study the role of cytokines as an immuno-molecular link between rising stress levels and an increase in CVD, hypertension, diabetes and obesity. Upon a qualitative comparative analysis of cytokine profiles, a total of 14 cytokines (IL-6, TNF-alpha, IFN-gamma, IL-10, etc.) were observed to be commonly involved in stress and aforementioned four metabolic disorders. Further analysis of quantitative studies has revealed that the cytokine profile for coronary artery disease (CAD) showed remarkable increase in a couple of cytokines. IL 9 registered an increase of 67 percent to reach a concentration of 75 pg/mL. IL 3, on the other hand, was absent in control candidates but reached 56 ± 14 pg/mL in CAD patients. In case of diabetes, IFN-gamma showed an increase of 290 pg/mL. For obesity it was observed that both MCP-1 and IL-1 beta fell by 12.2 pg/mL to reach 44.4 pg/mL in obese patients. A fall of approximately 50 pg/mL was observed in the concentration of VEGF in obese patients. Similarly, hypertension was marked by reduction in concentration of several cytokines - MCP-1 and VEGF being a couple of them. Apart from performing an analysis of cytokine profiles, an innovative database [Cytokine database of Stress and Metabolic disorders (CdoSM)-https://www.akbi-nsut.co.in/] has also been created comprising cytokines involved in stress and the aforementioned metabolic disorders. Upon accessing the database, a user can find the list cytokines associated with a particular condition along with information on cytokine receptor/s; related research articles; cytokine concentration in control v/s diseased candidates for some specific cytokines and the Uniprot ID for the respective cytokine. Database can be accessed by the link-https://www.akbi-nsut.co.in/.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03375-0.

Acute sleep deprivation disrupts emotion, cognition, inflammation, and cortisol in young healthy adults

Chronic sleep deprivation has been demonstrated to diminish cognitive performance, alter mood states, and concomitantly dysregulate inflammation and stress hormones. At present, however, there is little understanding of how an acute sleep deprivation may collectively affect these factors and alter functioning. The present study aimed to determine the extent to which 24-h of sleep deprivation influences inflammatory cytokines, stress hormones, cognitive processing across domains, and emotion states. To that end, 23 participants (mean age = 20.78 years, SD = 2.87) filled out clinical health questionnaires measured by the Pittsburgh Sleep Quality Index, Morningness Eveningness Questionnaire, and Center for Epidemiological Studies Depression Scale. Actigraph was worn for seven days across testing to record sleep duration. At each session participants underwent a series of measures, including saliva and blood samples for quantification of leptin, ghrelin, IL-1β, IL-6, CRP, and cortisol levels, they completed a cognitive battery using an iPad, and an emotion battery. We found that an acute sleep deprivation, limited to a 24 h period, increases negative emotion states such as anxiety, fatigue, confusion, and depression. In conjunction, sleep deprivation results in increased inflammation and decreased cortisol levels in the morning, that are accompanied by deficits in vigilance and impulsivity. Combined, these results suggest that individuals who undergo 24 h sleep deprivation will induce systemic alterations to inflammation and endocrine functioning, while concomitantly increasing negative emotions.

Time of day differences in appetite and gut hormone responses to meal and stress challenges in adults with normal-weight and obesity

BACKGROUND

. Lifestyle factors like time of eating and stress exposure may impact physiology to promote excess weight gain. To understand behavioral and physiological mechanisms underlying these potential effects, we compared appetite and gut hormone responses to a series of meal and stress challenges beginning in the morning and the afternoon, in adults with normal-weight and obesity.

METHOD

. Thirty-two adults (16 with normal-weight, 16 with obesity) underwent the same test protocol on different days, each following an 8 h fast. On one day the protocol began in the morning (AM condition); on the other day it began in the late afternoon (PM condition). On each day they first received a standardized liquid meal (9:00am/4:00pm), then a stress test (Socially-Evaluated Cold Pressor Test, 11:10am/6:10pm), then an ad libitum buffet meal (11:40am/6:40pm). Appetite and stress ratings were obtained, and blood was drawn for measures of ghrelin, PYY, GLP-1, insulin, glucose, cortisol and leptin. Acetaminophen was administered as a tracer to assess gastric emptying of the liquid meal.

RESULTS

. Across all three challenges, AUC cortisol was lower in the PM vs. AM condition (all p<.001), and AUC insulin and leptin were higher in the obesity vs. normal-weight group (all p<.001). For the standardized liquid meal only, AUC hunger, desire to eat and ghrelin were greater in the PM vs. AM condition (all p<0.05), and AUC ghrelin was lower in the obesity vs. normal-weight group, even when controlling for baseline values (p<0.05). AUC glucose was higher in the evening for the normal-weight group only (condition x group interaction p<0.05). Post-liquid meal gastric emptying as indexed by AUC acetaminophen was slower in the PM vs. AM (p<.01). For the stress test, AUC cortisol was lower in the PM than the AM condition even when controlling for baseline values (p<.05). AUC leptin was lower in the evening in the obesity group only (condition x group interaction p<0.01). PYY showed an acute decrease post-stressor in the normal-weight but not the obesity group (p<.05). Post-stress ad libitum buffet meal intake was similar in the evening and morning conditions, and higher in the obesity group (p<0.05). Only among the obesity group in the evening condition, higher stressor-associated stress ratings were associated with lesser fullness in relation to the buffet meal (p<0.05).

CONCLUSIONS

. Normal-weight individuals and those with obesity may be at risk of evening overeating as a result of differential appetite and gut hormone responses following meal intake and stress exposure.

Anxiolytic effects of chewing gum during preoperative fasting and patient-centered outcome in female patients undergoing elective gynecologic surgery: randomized controlled study

Although previous studies reported that chewing gum during the preoperative fasting has the benefits of alleviating anxiety and dry mouth, preoperative chewing gum has yet to be accepted as a standard practice due to conventional anesthetic custom. Our study aimed to prospectively evaluate the effects of gum chewing on preoperative anxiety and patient's discomfort in female patients undergoing gynecologic surgery. Ninety-four patients were enrolled and randomized either into conventional fasting group (control group) or chewing gum with fasting group (gum group). The control group was instructed to fast from 3 p.m. on the day before surgery. The gum group performed preoperative fasting in the same manner, but was encouraged to chew gum freely during the fasting period. The primary endpoint was the degree of preoperative anxiety. For the evaluation of preoperative anxiety, Amsterdam preoperative anxiety and information scale (APAIS) was used. Preoperative gastric fluid volume and acidity were also measured as the secondary outcomes. Preoperative anxiety using APAIS was significantly lower in the gum group compared to the control group (control group vs. gum group: 20.9 vs. 17.8, p = 0.009). However, there was no significant difference in the gastric fluid analysis between the groups. In the female patients for elective gynecologic surgery, chewing gum during the preoperative fasting period helped to alleviate preoperative anxiety without additional increase of pulmonary aspiration risks.Trial registration: KCT0004422 (05/11/2019, https://cris.nih.go.kr ; registration number).

The Negative Impact of Night Shifts on Diet in Emergency Healthcare Workers

Despite the consequences of night-shift work, the diet of night-shift workers has not been widely studied. To date, there are no studies related to food intake among emergency healthcare workers (HCWs). We performed a prospective observational study to assess the influence of night work on the diet of emergency HCWs. We monitored 24-h food intake during a day shift and the consecutive night, and during night work and the daytime beforehand. We analyzed 184 emergency HCWs' food intakes. Emergency HCWs had 14.7% lower (-206 kcal) of their 24-h energy intake during night shifts compared to their day-shift colleagues (1606.7 ± 748.2 vs. 1400.4 ± 708.3 kcal, p = 0.049) and a 16.7% decrease in water consumption (1451.4 ± 496.8 vs. 1208.3 ± 513.9 mL/day, p = 0.010). Compared to day shifts, night-shift had 8.7% lower carbohydrates, 17.6% proteins, and 18.7% lipids. During the night shift the proportion of emergency HCWs who did not drink for 4 h, 8 h and 12 h increased by 20.5%, 17.5%, and 9.1%, respectively. For those who did not eat for 4 h, 8 h and 12 h increased by 46.8%, 27.7%, and 17.7%, respectively. A night shift has a huge negative impact on both the amount and quality of nutrients consumed by emergency healthcare workers.

Early Life Stress, Brain Development, and Obesity Risk: Is Oxytocin the Missing Link?

Obesity disease results from a dysfunctional modulation of the energy balance whose master regulator is the central nervous system. The neural circuitries involved in such function complete their maturation during early postnatal periods, when the brain is highly plastic and profoundly influenced by the environment. This phenomenon is considered as an evolutionary strategy, whereby metabolic functions are adjusted to environmental cues, such as food availability and maternal care. In this timeframe, adverse stimuli may program the body metabolism to maximize energy storage abilities to cope with hostile conditions. Consistently, the prevalence of obesity is higher among individuals who experienced early life stress (ELS). Oxytocin, a hypothalamic neurohormone, regulates the energy balance and modulates social, emotional, and eating behaviors, exerting both central and peripheral actions. Oxytocin closely cooperates with leptin in regulating energy homeostasis. Both oxytocin and leptin impact the neurodevelopment during critical periods and are affected by ELS and obesity. In this review article, we report evidence from the literature describing the effect of postnatal ELS (specifically, disorganized/inconstant maternal care) on the vulnerability to obesity with a focus on the role of oxytocin. We emphasize the existing research gaps and highlight promising directions worthy of exploration. Based on the available data, alterations in the oxytocin system may in part mediate the ELS-induced susceptibility to obesity.