Role of leptin as a link between metabolism and the immune system

Role of leptin and adiponectin in immune response and inflammation

Adipose tissue has gained significant attention for its role in immune response and inflammation through the secretion of adipokines. Adipokines, such as leptin and adiponectin, are secreted by adipose tissue and have been implicated in various physiological processes, with a focus on their role in modulating immune responses and inflammation. Leptin and adiponectin are the most abundant adipokines in human, playing a crucial role in regulating functions of the heart, skeletal muscle, growth, and inflammation. Leptin, a pro-inflammatory adipokine, is involved in controlling food intake and energy expenditure, and it influences immune cell activation and cytokine production. In contrast, adiponectin, an anti-inflammatory adipokine, circulates at high levels in the plasma and modulates immune cell functions, counteracting the effects of leptin. Here we provided an overview of the role of adipokines in immune response and inflammation. In addition，The leptin-adiponectin ratio (Adpn/Lep) has emerged as a significant indicator of various metabolic diseases and conditions. Further research is needed to fully elucidate the mechanisms by which adipokines influence immune responses and to identify potential therapeutic targets for inflammatory and metabolic disorders.

Effects of multi-strain probiotics supplementation on body adiposity and metabolic profile in individuals with hypertension and overweight following an energy-restricted diet: A randomized clinical trial

BACKGROUND & AIMS

Recent evidence suggests that gut microbiota has a potential role in the pathophysiology of obesity and other cardiovascular disease (CVD) risk factors, including hypertension, dyslipidemia, and type 2 diabetes. However, clinical trials evaluating the effects of probiotics supplementation on these outcomes have found inconsistent results, probably due to the wide heterogeneity in trial designs. In addition, there is a lack of studies investigating whether probiotics can enhance the beneficial effects of caloric restriction in individuals with increased risk of CVD as individuals with hypertension and excess body adiposity. Thus, the aim of this study was to evaluate the effects of multi-strain probiotics supplementation on body adiposity, glycemic homeostasis, lipid profile, and serum adipokine levels in individuals with hypertension and excess body weight following an energy restricted diet.

METHODS

A randomized, double-blind, placebo controlled clinical trial was conducted for 12 weeks. Were included 66 individuals aged between 40 and 65 years; both sexes; body mass index (BMI) ≥ 25 and < 40 kg/m2 and diagnosis of hypertension. Were excluded smokers; individuals using probiotics, prebiotics, symbiotics and antibiotics in the last 3 months; presenting diabetes, chronic kidney disease or liver failure; and pregnant and lactating women. Participants were allocated into 2 groups: group with supplementation of 8 probiotic strains in capsules (3 × 1010 CFU/day) or control group (placebo capsules). Both groups followed a low-calorie diet. Participants underwent anthropometric, body composition (dual-energy radiological absorptiometry) and biochemical (glucose metabolism, lipid profile, adiponectin, and leptin) evaluation at baseline and at the end of the study.

RESULTS

After 12 weeks of intervention, the probiotics group presented: a) reduction of body weight, BMI, circumferences of waist, hip and neck and waist-to-height ratio; b) decrease in total fat mass (kg); and c) reduction of glycated hemoglobin (HbA1c). In the control group, it was observed: a) significant reduction in all anthropometric variables; b) significant reduction in total fat mass (kg and %), trunk fat mass (kg), visceral fat and load capacity index. In the comparison between groups, there was a higher decrease in HbA1c in the probiotics group (p < 0.05).

CONCLUSION

Multi-strain probiotics supplementation associated with energy restriction in individuals with excess body weight and hypertension promoted a significant improvement in glucose homeostasis assessed by HbA1c. The clinical trial was registered at www.ensaiosclinicos.gov.br: RBR-7jw4ry.

Leptin as a potential neuroprotective target in Parkinson's Disease: Exploring its role in Neuroinflammation, oxidative Stress, and dopaminergic neurodegeneration

Parkinson's disease (PD) is the second most commonneurodegenerative disease, characterized bybradykinesia, resting tremor, stiffness, and postural instabilityresulting due to the progressive loss ofdopaminergic neurons in the substantia nigra (SN). The pathophysiology of PDis extremely complex and involves mitochondrial dysfunction, oxidative stress, neuroinflammation, and disruption of protein homeostasis. Its progression is affected by both environmental and genetic factors, including mutations in the alpha-synuclein (SNCA), PTEN-induced kinase 1 (PINK1), and leucine-rich repeat kinase 2 (LRRK2) genes. Leptin, primarily secreted by the adipose tissue, has garnered significant interest for its involvement in neuroprotective mechanisms and potential role in the progression of PD. Its receptors located in the SN and hippocampus region indicate its role in neuronal survival and function. The role of leptin in the central nervous system (CNS) highlights its impact on neuroinflammation, oxidative stress, and synaptic plasticity. Recent studies indicate that through activation of Janus kinase/signal transducer and activator of transcription (JAK2/STAT3) and the phosphoinositide 3 kinase (PI3 K)/Akt pathways, leptin may exert a neuroprotective effect by preventing the degeneration of dopaminergic neurons, which marked as the hallmark in the pathophysiology of PD. Additionally, leptin's interaction with neurotrophic factors and its ability to enhance synaptic plasticity highlight its vital role in preserving neuronal health. This review summarizes the role of leptin as a neuroprotective mechanism in PD and explores its potential role as a therapeutic target for treatment to enhance neuroprotection and clinical outcome, by addressing the neurodegenerative characteristics associated with PD.

Metabolic Signalling Peptides and Their Relation to Clinical and Demographic Characteristics in Acute and Recovered Females with Anorexia Nervosa

Background/Objectives: Recent research has established that metabolic factors may increase the vulnerability to develop anorexia nervosa (AN). The aim of this study was to explore the serum concentrations of leptin, insulin-like growth factor-1 (IGF-1), insulin and insulin receptor substrate (IRS-1) as possible state or trait biomarkers for AN in the acute and recovery (recAN) phases. Our secondary aim was to test associations between the tested markers and demographic and clinical characteristics. Methods: This cross-sectional study included data from 56 participants with AN, 24 recAN participants and 51 healthy controls (HCs). Enzyme-linked immunosorbent assays (ELISAs) were used to quantify serum concentrations of leptin, IGF-1, insulin and IRS-1. An analysis of covariance (ANCOVA) and linear regression models were utilised to test our results. Results: There were significant differences with a large effect size between the groups for serum leptin (p < 0.001; d = 0.80), whereby people with AN had lower leptin than those with recAN (p = 0.023; d = 0.35) and HCs (p < 0.001; d = 0.74). The between-group comparison of IGF-1 did not reach significance, although the effect size was moderate (d = 0.6) and was driven by lower levels of IGF-1 in people with acute AN compared to HCs (p = 0.036; d = 0.53). Serum insulin and IRS-1 did not differ between groups. Conclusions: Low leptin levels seen in individuals with AN may be due to starvation leading to fatty tissue depletion. Understanding the regulation of IGF-1 and insulin signalling over the course of the disorder requires further investigation.

Leptin and Insulin in COPD: Unveiling the Metabolic-Inflammatory Axis-A Narrative Review

Chronic obstructive pulmonary disease (COPD) is a progressive and debilitating condition characterized by airflow limitations and systemic inflammation. The interaction between the metabolic and inflammatory pathways plays a key role in disease progression, with leptin and insulin emerging as pivotal metabolic regulators. Leptin, an adipokine that regulates energy homeostasis, and insulin, the primary regulator of glucose metabolism, are both altered in COPD patients. This narrative review provides an in-depth examination of the roles of leptin and insulin in COPD pathogenesis, focusing on the molecular mechanisms through which these metabolic regulators interact with inflammatory pathways and how their dysregulation contributes to a spectrum of extrapulmonary manifestations. These disturbances not only exacerbate COPD symptoms but also increase the risk of comorbidities such as metabolic syndrome, diabetes, cardiovascular disease, or muscle wasting. By exploring the underlying mechanisms of leptin and insulin dysregulation in COPD, this review underscores the significance of the metabolic-inflammatory axis, suggesting that restoring metabolic balance through leptin and insulin modulation could offer novel therapeutic strategies for improving clinical outcomes.

Decreased number of myeloid-derived suppressor cells in the placental trophoblast of gestational diabetes mellitus. Possible role of leptin

Gestational diabetes mellitus (GDM) is the most common complication of pregnancy and significantly increases both maternal and fetal morbidity and mortality. Inflammation is a hallmark of GDM, and placental inflammation may play a key role in the pathophysiology of the disease. Myeloid-derived suppressor cells (MDSCs), which are innate immunosuppressive, are thought to contribute to feto-maternal tolerance. In normal pregnancies, elevated levels of MDSCs have been observed in both peripheral and umbilical cord blood. Our hypothesis postulates that trophoblasts from placentas belonging to women with GDM may have lower levels of MDSCs compared to trophoblasts from placentas originating from healthy pregnancies. Furthermore, since leptin is overexpressed in the placenta of GDM patients, we hypothesized that leptin might contribute to the reduction of MDSCs. To test this, we investigated the in vitro effects of leptin on MDSC levels in isolated peripheral blood leukocytes after 24 h of incubation. Our findings indicate that trophoblasts from placentas from women with GDM contain a lower percentage of MDSCs compared to trophoblasts from healthy pregnancies. In addition, in vitro studies demonstrated that leptin reduces the number of MDSCs in peripheral blood leukocytes. In conclusion, MDSCs are decreased in placentas from pregnancies with GDM, and leptin appears to reduce the number of MDSCs in leukocytes isolated in vitro. Increased leptin expression in trophoblasts from placentas of women with GDM may contribute to the lower levels of MDSCs, potentially playing a role in placental inflammation. However, further investigations are required to fully elucidate this mechanism.

Frozen Shoulder as a Metabolic and Immune Disorder: Potential Roles of Leptin Resistance, JAK-STAT Dysregulation, and Fibrosis

Frozen shoulder (FS) is a complex and multifactorial condition characterized by persistent inflammation, fibrosis, and metabolic dysregulation. Despite extensive research, the underlying drivers of FS remain poorly understood. Recent findings indicate the coexistence of pro-inflammatory and fibrosis-resolving macrophages within affected tissues, suggesting a dysregulated immune response influenced by metabolic and neuroendocrine factors. This review proposes that leptin resistance, a hallmark of metabolic syndrome and chronic inflammation, may play a central role in FS pathogenesis by impairing macrophage polarization, perpetuating inflammation, and disrupting fibrosis resolution. The JAK-STAT signaling pathway, critically modulated by leptin resistance, may further contribute to immune dysregulation by sustaining inflammatory macrophage activation and interfering with tissue remodeling. Additionally, FS shares pathogenic features with fibrotic diseases driven by TGF-β signaling, mitochondrial dysfunction, and circadian disruption, further linking systemic metabolic dysfunction to localized fibrotic pathology. Beyond immune and metabolic regulation, alterations in gut microbiota, bacterial translocation, and chronic psychosocial stress may further exacerbate systemic inflammation and neuroendocrine imbalances, intensifying JAK-STAT dysregulation and leptin resistance. By examining the intricate interplay between metabolism, immune function, and fibrotic remodeling, this review highlights targeting leptin sensitivity, JAK-STAT modulation, and mitochondrial restoration as novel therapeutic strategies for FS treatment. Future research should explore these interconnections to develop integrative interventions that address both the metabolic and immune dysregulation underlying FS, ultimately improving clinical outcomes.

Leptin and Leptin Signaling in Multiple Sclerosis: A Narrative Review

Obesity, a pandemic health problem, is now considered as a chronic inflammatory state, related to many autoimmune diseases, such as multiple sclerosis. Thus, adipokines, inflammatory mediators secreted by adipose tissue, play an important role modulating the immune response. In this context, obesity, especially during adolescent age, seems to be a key factor for the development of multiple sclerosis. Leptin, the main pro-inflammatory adipokine secreted by the adipose tissue, has been found increased in patients with multiple sclerosis and is able to regulate the immune system promoting a pro-inflammatory response. Leptin signaling in both innate and adaptative immune cells might have immunomodulatory effects in the context of multiple sclerosis. In this way, leptin has been found to produce a Th1 and Th17 response, increasing M1 macrophages and decreasing regulatory T cells and Th2 response. Moreover, circulating inflammatory adipokines, such as leptin, have been found in people with multiple sclerosis. In the present work, we are reviewing literature to update the body of knowledge regarding the role of obesity and leptin in multiple sclerosis.

Identification of genes involved in energy metabolism in preeclampsia and discovery of early biomarkers

Background

Preeclampsia is a complex pregnancy condition marked by hypertension and organ dysfunction, posing significant risks to maternal and fetal health. This study investigates the role of energy metabolism-associated genes in preeclampsia development and identifies potential early diagnostic biomarkers.

Methods

Preeclampsia datasets from Gene Expression Omnibus were analyzed for batch correction, normalization, and differential expression. Enrichment analyses using gene ontology, Kyoto Encyclopedia of Genes and Genomes, and gene set enrichment were performed. Protein-protein interaction networks were constructed to identify key genes, and regulatory networks involving transcription factors, miRNAs, and RNA-binding proteins were established. Differential expression was validated with receiver operating characteristic curve analyses, and immune infiltration was assessed.

Results

Six energy metabolism-related genes were identified. Enrichment analyses revealed their involvement in glycolysis, gluconeogenesis, lipid transport, bone remodeling, and glucagon secretion. Key differentially expressed genes included CRH(Corticotropin-Releasing Hormone), LEP(Leptin), PDK4(Pyruvate Dehydrogenase Kinase Isozyme 4), SPP1(Secreted Phosphoprotein 1), and SST(Somatostatin). PDK4 exhibited moderate accuracy in receiver operating characteristic analysis. Immune infiltration analysis indicated significant differences between preeclampsia and control samples. qRT-PCR confirmed LEP and CRH increased, while SPP1 expression in preeclampsia samples.

Conclusion

Dysregulated energy metabolism-related genes may contribute to preeclampsia through metabolic and immune changes. Identifying these genes aids in understanding preeclampsia's molecular basis and early diagnosis. Future studies should validate these markers in larger cohorts and explore targeted treatments.

Inflammatory biomarkers as cost-effective predictive tools in metabolic dysfunction-associated fatty liver disease

Qu and Li emphasize a fundamental aspect of metabolic dysfunction-associated fatty liver disease in their manuscript, focusing on the critical need for non-invasive diagnostic tools to improve risk stratification and predict the progression to severe liver complications. Affecting approximately 25% of the global population, metabolic dysfunction-associated fatty liver disease is the most common chronic liver condition, with higher prevalence among those with obesity. This letter stresses the importance of early diagnosis and intervention, especially given the rising incidence of obesity and metabolic syndrome. Research advancements provide insight into the potential of biomarkers (particularly inflammation-related) as predictive tools for disease progression and treatment response. This overview addresses pleiotropic biomarkers linked to chronic inflammation and cardiometabolic disorders, which may aid in risk stratification and treatment efficacy monitoring. Despite progress, significant knowledge gaps remain in the clinical application of these biomarkers, necessitating further research to establish standardized protocols and validate their utility in clinical practice. Understanding the complex interactions among these factors opens new avenues to enhance risk assessment, leading to better patient outcomes and addressing the public health burden of this worldwide condition.

Association between metabolic syndrome and benign prostatic hyperplasia: The underlying molecular connection

Benign prostatic hyperplasia (BPH), a common cause of lower urinary tract symptoms (LUTS), has been recently regarded as a metabolic disease. Metabolic syndrome (MetS) is a constellation of metabolic disarrangements, including insulin resistance, obesity, hypertension, and dyslipidemia, and it has been established that these components of MetS are important contributing factors exacerbating the degree of prostatic enlargement and bladder outlet obstruction among patients with BPH. Clinical and experimental studies demonstrated that many molecules, such as insulin, insulin-like growth factor 1 (IGF-1), androgen and estrogen, and adipokines, are involved in the overlapping pathogenesis of BPH and MetS, indicating that clinicians might be able to simultaneously alleviate or cure two diseases by choosing appropriate medications. This article aims to systematically review the pathophysiological aspect and traditional etiology and pathogenesis of BPH and discuss the intricate association between MetS and BPH from the molecular point of view, in an attempt to provide stronger evidence for better treatment of two diseases.

The dietary inflammatory index and asthma prevalence: a cross-sectional analysis from NHANES

Background

Inflammation is a key factor in the development of asthma, and diet significantly influences inflammatory responses. This study examines the relationship between the Dietary Inflammatory Index (DII) and asthma prevalence.

Methods

We conducted a cross-sectional analysis using data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Demographic details, anthropometric measurements, dietary habits, lifestyle factors, and asthma status were recorded for all participants. Multivariable logistic regression was utilized to assess the relationship between DII and asthma prevalence. Additionally, restricted cubic spline (RCS) analysis was employed to explore the nonlinearity and dose-response relationship between DII and asthma risk. Subgroup analyses were stratified by gender, age, race, body mass index (BMI), poverty income ratio (PIR), education, smoking status, alcohol use, and family medical history to dissect the association between DII and asthma across diverse populations.

Results

The analysis included 37,283 adults from NHANES. After adjusting for potential confounders in the multivariable logistic regression model, a significant positive association was identified between DII and asthma (OR, 95% CI: 1.05, 1.02-1.09, per 1 SD increase). The RCS analysis revealed a nonlinear association (p for nonlinearity = 0.0026), with an inflection point at 1.366, beyond which an increase in DII was significantly associated with asthma risk. Furthermore, the stratified analyses indicated a positive association between DII and asthma in the majority of subgroups.

Conclusion

The findings underscore a significant and nonlinear association between DII and asthma. To enhance asthma prevention and management, greater emphasis should be placed on modulating dietary-induced inflammation.

The Expression of Genes Related to Reverse Cholesterol Transport and Leptin Receptor Pathways in Peripheral Blood Mononuclear Cells Are Decreased in Morbid Obesity and Related to Liver Function

Obesity is frequently accompanied by non-alcoholic fatty liver disease (NAFLD). These two diseases are associated with altered lipid metabolism, in which reverse cholesterol transport (LXRα/ABCA1/ABCG1) and leptin response (leptin receptor (Ob-Rb)/Sam68) are involved. The two pathways were evaluated in peripheral blood mononuclear cells (PBMCs) from 86 patients with morbid obesity (MO) before and six months after Roux-en-Y gastric bypass (RYGB) and 38 non-obese subjects. In the LXRα pathway, LXRα, ABCA1, and ABCG1 mRNA expressions were decreased in MO compared to non-obese subjects (p < 0.001, respectively). Ob-Rb was decreased (p < 0.001), whereas Sam68 was increased (p < 0.001) in MO. RYGB did not change mRNA gene expressions. In the MO group, the LXRα pathway (LXRα/ABCA1/ABCG1) negatively correlated with obesity-related variables (weight, body mass index, and hip), inflammation (C-reactive protein), and liver function (alanine-aminotransferase, alkaline phosphatase, and fatty liver index), and positively with serum albumin. In the Ob-R pathway, Ob-Rb and Sam68 negatively correlated with alanine-aminotransferase and positively with albumin. The alteration of LXRα and Ob-R pathways may play an important role in NAFLD development in MO. It is possible that MO patients may require more than 6 months following RYBGB to normalize gene expression related to reverse cholesterol transport or leptin responsiveness.

Microbiota-gut-brain axis and its therapeutic applications in neurodegenerative diseases

The human gastrointestinal tract is populated with a diverse microbial community. The vast genetic and metabolic potential of the gut microbiome underpins its ubiquity in nearly every aspect of human biology, including health maintenance, development, aging, and disease. The advent of new sequencing technologies and culture-independent methods has allowed researchers to move beyond correlative studies toward mechanistic explorations to shed light on microbiome-host interactions. Evidence has unveiled the bidirectional communication between the gut microbiome and the central nervous system, referred to as the "microbiota-gut-brain axis". The microbiota-gut-brain axis represents an important regulator of glial functions, making it an actionable target to ameliorate the development and progression of neurodegenerative diseases. In this review, we discuss the mechanisms of the microbiota-gut-brain axis in neurodegenerative diseases. As the gut microbiome provides essential cues to microglia, astrocytes, and oligodendrocytes, we examine the communications between gut microbiota and these glial cells during healthy states and neurodegenerative diseases. Subsequently, we discuss the mechanisms of the microbiota-gut-brain axis in neurodegenerative diseases using a metabolite-centric approach, while also examining the role of gut microbiota-related neurotransmitters and gut hormones. Next, we examine the potential of targeting the intestinal barrier, blood-brain barrier, meninges, and peripheral immune system to counteract glial dysfunction in neurodegeneration. Finally, we conclude by assessing the pre-clinical and clinical evidence of probiotics, prebiotics, and fecal microbiota transplantation in neurodegenerative diseases. A thorough comprehension of the microbiota-gut-brain axis will foster the development of effective therapeutic interventions for the management of neurodegenerative diseases.

Role of Leptin in Obesity, Cardiovascular Disease, and Type 2 Diabetes

Diabetes mellitus (DM) is a highly prevalent disease worldwide, estimated to affect 1 in every 11 adults; among them, 90-95% of cases are type 2 diabetes mellitus. This is partly attributed to the surge in the prevalence of obesity, which has reached epidemic proportions since 2008. In these patients, cardiovascular (CV) risk stands as the primary cause of morbidity and mortality, placing a substantial burden on healthcare systems due to the potential for macrovascular and microvascular complications. In this context, leptin, an adipocyte-derived hormone, plays a fundamental role. This hormone is essential for regulating the cellular metabolism and energy balance, controlling inflammatory responses, and maintaining CV system homeostasis. Thus, leptin resistance not only contributes to weight gain but may also lead to increased cardiac inflammation, greater fibrosis, hypertension, and impairment of the cardiac metabolism. Understanding the relationship between leptin resistance and CV risk in obese individuals with type 2 DM (T2DM) could improve the management and prevention of this complication. Therefore, in this narrative review, we will discuss the evidence linking leptin with the presence, severity, and/or prognosis of obesity and T2DM regarding CV disease, aiming to shed light on the potential implications for better management and preventive strategies.

Adolescent intermittent ethanol (AIE) produces lasting, sex-specific changes in rat body fat independent of changes in white blood cell composition

Early initiation of alcohol use during adolescence, and adolescent binge drinking are risk factors for the development of alcohol use disorder later in life. Adolescence is a time of rapid sex-dependent neural, physiological, and behavioral changes as well as a period of heightened vulnerability to many effects of alcohol. The goal of the present studies was to determine age-related changes in blood (leukocyte populations) and body composition across adolescence and early adulthood, and to investigate whether adolescent intermittent ethanol (AIE) exposure would alter the trajectory of adolescent development on these broad physiological parameters. We observed significant ontogenetic changes in leukocyte populations that were mirrored by an age-related increase in cytokine expression among mixed populations of circulating leukocytes. Despite these developmental changes, AIE did not significantly alter overall leukocyte numbers or cytokine gene expression. However, AIE led to sex-specific changes in body fat mass and fat percentage, with AIE-exposed male rats showing significantly decreased fat levels and female rats showing significantly increased fat levels relative to controls. These changes suggest that while AIE may not alter overall leukocyte levels, more complex phenotypic changes in leukocyte populations could underlie previously reported differences in cytokine expression. Coupled with long-term shifts in adipocyte levels, this could have long-lasting effects on innate immunity and the capacity of individuals to respond to later immunological and physiological threats.

Adipokines in atopic dermatitis: the link between obesity and atopic dermatitis

Atopic dermatitis (AD) is a chronic skin condition with intense pruritus, eczema, and dry skin. The recurrent intense pruritus and numerous complications in patients with AD can profoundly affect their quality of life. Obesity is one of its comorbidities that has been confirmed to be the hazard factor of AD and also worsen its severity. Nevertheless, the specific mechanisms that explain the connection between obesity and AD remain incompletely recognized. Recent studies have built hopes on various adipokines to explain this connection. Adipokines, which are disturbed by an obese state, may lead to immune system imbalances in people with AD and promote the development of the disease. This review focuses on the abnormal expression patterns of adipokines in patients with AD and their potential regulatory molecular mechanisms associated with AD. The connection between AD and obesity is elucidated through the involvement of adipokines. This conduces to the in-depth exploration of AD pathogenesis and provides a new perspective to develop therapeutic targets.

Leptin and Leptin Receptor Polymorphisms in Infants and Their Parents: Correlation with Preterm Birth

It has been proven that single-nucleotide polymorphisms (SNPs) in LEP and LEPR genes could predispose individuals to an increased risk of pregnancy adverse outcomes (PAOs) such as recurrent pregnancy loss (RPL) and pre-eclampsia. Preterm birth (PTB) is the leading cause of infant mortality. We decided to investigate the correlation between PTB and LEP and LEPR SNPs. The study cohort included families who underwent spontaneous PTB and control samples of families who had at-term-born (≥37 weeks of gestational age) children. Swabs were performed by rubbing the sticky end for about 30 s on the gum and on the inside of the cheek, allowing us to collect the flaking cells of the oral mucosa. Genotyping of the three SNPs-LEPRA668G, LEPG2548A and A19G-was carried out via an ARMS-MAMA real-time PCR procedure, as previously described. Regarding LEPG2548A, we found that the most expressed genotype in infants both in the preterm and the at-term group was AG; however, we did not discover any statistically significant difference (p = 0.97). Considering LEPA19G, none among the infants and parents were found to carry the AA genotype. No statistically significant differences were found between children, mothers and fathers belonging to preterm and at-term groups. We did not find a statistically significant association in newborns and their mother, but our results show a statistical correlation with the LEPRA668G genotype GG of the father. This fact can contribute to defining genetic risk factors for PTB. Further studies are certainly needed to better clarify the role of genetics in influencing preterm delivery.

Zinc homeostasis and redox alterations in obesity

Impairment of both cellular zinc and redox homeostasis is a feature of several chronic diseases, including obesity. A significant two-way interaction exists between redox metabolism and the relatively redox-inert zinc ion. Redox metabolism critically influences zinc homeostasis and controls its cellular availability for various cellular functions by regulating zinc exchange from/to zinc-binding proteins. Zinc can regulate redox metabolism and exhibits multiple pro-antioxidant properties. On the other hand, even minor disturbances in zinc status and zinc homeostasis affect systemic and cellular redox homeostasis. At the cellular level, zinc homeostasis is regulated by a multi-layered machinery consisting of zinc-binding molecules, zinc sensors, and two selective families of zinc transporters, the Zinc Transporter (ZnT) and Zrt, Irt-like protein (ZIP). In the present review, we summarize the current state of knowledge on the role of the mutual interaction between zinc and redox homeostasis in physiology and pathophysiology, pointing to the role of zinc in the alterations responsible for redox stress in obesity. Since zinc transporters primarily control zinc homeostasis, we describe how changes in the expression and activity of these zinc-regulating proteins are associated with obesity.

Leptin antagonism attenuates hypertension and renal injury in an experimental model of autoimmune disease

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder that is characterized by B- and T-lymphocyte dysfunction and altered cytokine production, including elevated levels of the adipocytokine leptin. Leptin has various immunomodulatory properties, including promoting the expansion of proinflammatory T lymphocytes and the proliferation and survival of B cells. In the present study, we hypothesized that leptin antagonism would improve B- and T-cell dysfunction and attenuate hypertension in an experimental model of SLE, the NZBWF1 mouse. To test this hypothesis, 28-week-old female control and SLE mice were administered 5 mg/kg of murine leptin superantagonist (LA) or vehicle via ip injection every other day for four weeks. Analysis of peripheral blood immune cell populations showed no changes in total CD45R+ B and CD3+ T cell percentages after treatment with LA. However, SLE mice treated with LA had an improved CD4/CD8 ratio and decreased CD3+CD4-CD8- double negative (DN) T cells. Blood pressure was higher in SLE than in control, and treatment with LA decreased blood pressure in SLE mice. Treatment with LA also delayed the onset of albuminuria and decreased glomerulosclerosis in SLE mice. Renal immune cell infiltration was significantly higher in SLE mice as compared with control, but LA treatment was associated with decreased levels of renal CD4+ T cells. In conclusion, these data suggest that leptin plays a pathogenic role in the development of hypertension in SLE, in part, by promoting the expansion of inflammatory DN T cells and the infiltration of T cells into the kidneys.

Dietary fructose-mediated adipocyte metabolism drives antitumor CD8+ T cell responses

Fructose consumption is associated with tumor growth and metastasis in mice, yet its impact on antitumor immune responses remains unclear. Here, we show that dietary fructose modulates adipocyte metabolism to enhance antitumor CD8+ T cell immune responses and control tumor growth. Transcriptional profiling of tumor-infiltrating CD8+ T cells reveals that dietary fructose mediates attenuated transition of CD8+ T cells to terminal exhaustion, leading to a superior antitumor efficacy. High-fructose feeding initiates adipocyte-derived leptin production in an mTORC1-dependent manner, thereby triggering leptin-boosted antitumor CD8+ T cell responses. Importantly, high plasma leptin levels are correlated with elevated plasma fructose concentrations and improved antitumor CD8+ T cell responses in patients with lung cancer. Our study characterizes a critical role for dietary fructose in shaping adipocyte metabolism to prime antitumor CD8+ T cell responses and highlights that the fructose-leptin axis may be harnessed for cancer immunotherapy.

Metabolic influences on T cell in psoriasis: a literature review

Psoriasis is a systemic inflammatory disease that frequently coexists with various other conditions, such as essential hypertension, diabetes, metabolic syndrome, and inflammatory bowel disease. The association between these diseases may be attributed to shared inflammatory pathways and abnormal immunomodulatory mechanisms. Furthermore, metabolites also play a regulatory role in the function of different immune cells involved in psoriasis pathogenesis, particularly T lymphocytes. In this review, we have summarized the current research progress on T cell metabolism in psoriasis, encompassing the regulation of metabolites in glucose metabolism, lipid metabolism, amino acid metabolism, and other pathways within T cells affected by psoriasis. We will also explore the interaction and mechanism between psoriatic metabolites and immune cells. Moreover, we further discussed the research progress of metabolomics in psoriasis to gain a deeper understanding of its pathogenesis and identify potential new therapeutic targets through identification of metabolic biomarkers associated with this condition.

Case report: Rapid improvements of anorexia nervosa and probable myalgic encephalomyelitis/chronic fatigue syndrome upon metreleptin treatment during two dosing episodes

A comorbidity of anorexia nervosa (AN) and myalgic encephalomyelitis (ME/CSF) is uncommon. A 17 years-old male adolescent with possible onset of ME/CFS after an Epstein Barr Virus infection (EBV) and later onset of AN during a second period of weight loss was twice treated off-label with metreleptin for 15 and 11 days, respectively. As in previous cases, eating disorder specific cognitions and mood improved. Interestingly, fatigue and post-exertional muscle pain (P-EMP) improved, too. We discuss potential mechanisms. Treatment with metreleptin may prove beneficial in AN and in ME/CSF associated with substantial weight loss.

Maternal obesity and high leptin levels prime pro-inflammatory pathways in human cord blood leukocytes

INTRODUCTION

Maternal obesity alters the immune function in the offspring. We hypothesize that maternal obesity and pro-inflammatory pathways induce leptin-related genes in neonatal monocytes, whereby high leptin levels enhance their inflammatory response.

METHODS

Transcriptional profiles of cord blood leukocytes (CBL) in basal and pro-inflammatory conditions were studied to determine differentially expressed genes (DEG). The DNA methylation profile of CB monocytes (CBM) of neonates born to control BMI mothers and women with obesity was assayed to identify differentially methylated probes (DMP). CBM-derived macrophages were cultured with or without leptin (10-100 ng/ml) and then stimulated with lipopolysaccharide (LPS, 100 ng/ml) and interferon-gamma (20 ng/ml) to assess the induction of TNF-α and IL-10 transcripts.

RESULTS

CBL from pregnancies with obesity (CBL-Ob) showed 12,183 DEG, affecting 49 out of 78 from the leptin pathway. Control CBM exposed to LPS showed 45 leptin-related DEG, an effect prevented by the co-exposure to LPS and IL-10. Conversely, CBM-Ob showed 5279 DMP enriched in insulin- and leptin-related genes, and Lasso regression of leptin-related DMP showed high predictive value for plasma leptin levels (r2 = 0.9897) and maternal BMI categories (AUC = 1). Chronic exposure to leptin increased TNF-α and decreased IL-10 levels in control BMI samples but not in Ob-CBM. Enhanced TNF-α induction after proinflammatory stimulation was observed in leptin-treated control BMI samples.

DISCUSSION

Obesity in pregnancy is associated with a distinctive expression and DNA methylation profile of leptin-related genes in cord blood monocytes, meanwhile, leptin enhances the expression of pro-inflammatory cytokines upon stimulation with M1-skewing agents.

How hypoxia affects microbiota metabolism in mice

Objective

To investigate the relationship between gut microbiota and the fecal metabolites of hypoxic environments in mice.

Methods

High-fat diet-induced obese mice (n = 20) and normal diet-fed mice (n = 20) were randomly divided into four groups: high altitude obese group (HOB), high altitude normal weight group (HN), low altitude obese group LOB (LOB), and low altitude normal weight group (LN). Fecal samples from each group were 16S rRNA gene sequenced, and five samples from each of the four groups above were selected for non-targeted fecal metabolomics analysis using liquid chromatography-mass spectrometry. The relationship between gut microbiota and fecal metabolites was analyzed using SIMCA 14.1, MetaboAnalyst 5.0 and R 4.1.11.

Results

(A) Body weight was significantly lower in the hypoxic obesity group than in the normoxic obesity group. (B) Differences in α-diversity and β-diversity were found in the fecal gut microbiota of mice of different body weights and altitude, and the diversity of gut microbiota was higher in the normal group than in the obese group; the results of the comparison between the two groups showed that Faecalibaculum, Romboutsia, Lactobacillus, and A2 were associated with obesity; Romboutsia was associated with hypoxia. (C) The metabolic profiles of fecal metabolites differed between groups: gut microbiota were associated with nucleotide and amino acid metabolism in the same body groups, while gut microbiota were associated with lipid and amino acid metabolism in the same oxygen concentration groups.

Conclusion

(a) Gut microbiota diversity was reduced in obese groups. Romboutsia was the dominant microbiota in the hypoxia group. (b) Gut microbiota were associated with nucleotide and amino acid metabolism in the same body weight groups, while they were associated with lipid and amino acid metabolism in the same altitude groups.

Mineral elements and adiposity-related consequences in adolescents with intellectual disabilities

BACKGROUND

Patients with intellectual disabilities are shown to have a limited capacity for cooperation, communication,and other biological consequences, which significantly require a specialized interest in healthcare professionals worldwide.

AIM

In this respect, the present study was designed to evaluate the levels mineral elements, and their correlation with oxidative stress markers and adiposity markers; leptin (L), adiponectin (A), and L/A ratio in adolescents with intellectual disabilities.

METHODS

A total of 350 schoolchildren aged (12-18 years) were randomly invited to participate in this prospective, observational study. Only 300 participants agreed to participate in this study. According to Intelligence quotients scores (IQ) measured by WISC-III, the participants were classified into two groups; the healthy control group (no = 180; IQ = 90-114); and the moderate intellectual disability (MID) group (no = 120; IQ = 35-49). Adiposity markers; body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), physical activity scores, adipokines biomarkers; leptin, adiponectin, L/A ratio, oxidative stress, and plasma mineral elements were evaluated by prevalidated questionnaires, inductively coupled plasma-mass spectrometry (ICP-MS), colorimetric, and immunoassay techniques.

RESULTS

Intellectual disability of moderate type was reported in 40% of the studied populations most of them are men aged 12-18 years (66.6% for men vs. 33.3 for females). Obesity was shown to be associated with the degree of intellectual disability of the students. There was a significant (P = 0.001) increase in the BMI, WHR, and WHtR scores as obesity markers with poor physical activity (P = 0.01) in students with poor disability compared to healthy controls (HC). The levels of leptin (P = 0.001), adiponectin (P = 0.01), and L/A ratio (P = 0.01) as adiposity biomarkers were significantly increased in students with MID compared to healthy controls. Also, oxidative stress measured by malondialdehyde (MDA) (P = 0.01) and total antioxidant capacity (TAC) (P = 0.01) were significantly increased in students with MID compared to healthy control subjects. In addition, mineral elements were shown to be linked with intellectual disability. The data showed that the levels of Fe, Mn, Zn, Hg, Pb, Ca, Cr, Mg, and Ni significantly (P = 0.001) increased, and the levels of Al, Na, K, Cu, and Zn/Cu ratio significantly (P = 0.001) decreased in subjects with MID compared to healthy controls. Correlation analysis concluded that changes in mineral elements significantly correlated with adiposity markers, oxidative stress, and the scores of intellectual disability (WISC III-IQ score).

CONCLUSION

The intellectual disability of moderate type (MID) was associated with abnormal changes in the levels of essential mineral elements and adipokines and increased levels of cellular oxidative stress. Thus, evaluating plasma mineral elements and adipokines levels could be a potential diagnostic parameter for diagnosing MID.

Metabolic and Bariatric Endoscopy: A Mini-Review

We are currently in a worldwide obesity pandemic, which is one of the most significant health problems of the 21st century. As the prevalence of obesity continues to rise, new and innovate treatments are becoming available. Metabolic and bariatric endoscopic procedures are exciting new areas of gastroenterology that have been developed as a direct response to the obesity crisis. These novel interventions offer a potentially reversible, less invasive, safer, and more cost-effective method of tackling obesity compared to traditional bariatric surgery. Minimally invasive endoscopic treatments are not entirely novel, but as technology has rapidly improved, many of the procedures have been proven to be extremely effective for weight loss and metabolic health, based on high-quality clinical trial data. This mini-review examines the existing evidence for the most prominent metabolic and bariatric procedures, followed by a discussion on the future trajectory of this emerging subspecialty.

Dynamic lipidome alterations associated with human health, disease and ageing

Lipids can be of endogenous or exogenous origin and affect diverse biological functions, including cell membrane maintenance, energy management and cellular signalling. Here, we report >800 lipid species, many of which are associated with health-to-disease transitions in diabetes, ageing and inflammation, as well as cytokine-lipidome networks. We performed comprehensive longitudinal lipidomic profiling and analysed >1,500 plasma samples from 112 participants followed for up to 9 years (average 3.2 years) to define the distinct physiological roles of complex lipid subclasses, including large and small triacylglycerols, ester- and ether-linked phosphatidylethanolamines, lysophosphatidylcholines, lysophosphatidylethanolamines, cholesterol esters and ceramides. Our findings reveal dynamic changes in the plasma lipidome during respiratory viral infection, insulin resistance and ageing, suggesting that lipids may have roles in immune homoeostasis and inflammation regulation. Individuals with insulin resistance exhibit disturbed immune homoeostasis, altered associations between lipids and clinical markers, and accelerated changes in specific lipid subclasses during ageing. Our dataset based on longitudinal deep lipidome profiling offers insights into personalized ageing, metabolic health and inflammation, potentially guiding future monitoring and intervention strategies.

Obesity and recurrent miscarriage: The interconnections between adipose tissue and the immune system

Currently, obesity is considered a global public health problem. It is the main risk factor for noncommunicable diseases and reproductive complications, such as recurrent miscarriage (RM). RM affects approximately 1% of couples of reproductive age, and recent studies suggest that its prevalence is increasing. Immunological abnormalities may be responsible for a significant number of cases of unexplained RM. Obesity is recognized as a chronic low-grade inflammatory condition. The accumulation of fat in obese adipose tissue promotes changes in the local and systemic immune response. Adipokines, exosomes, micro-RNAs, lipids, and other factors released or secreted by adipose tissue are responsible for the interconnection between obesity and the immune system. Obesity-induced dysregulation of the innate and acquired immune response is also involved in the immunopathology of pregnancy loss in patients with unexplained RM. Therefore, understanding the communication pathways between maternal adipose tissue and the immune response in women living with obesity and RM is an important objective. Thus, diagnostic tools and new immunomodulatory therapies may be proposed for the management of patients with concurrent obesity and RM.

Relationship between leptin and white blood cells: a potential role in infection susceptibility and severity-the Olivetti Heart Study

A number of evidence showed an emerging role of leptin on immune system, involving inflammation, and innate and adaptive immunity. Few observational studies have evaluated the relationship between leptin and immunity, albeit with low statistical power and methodological differences. Therefore, the aim of this study was to evaluate the potential role of leptin on the immunity, expressed as white blood cells (WBC)-and its subpopulations, by comprehensive multivariate models in a sample of adult men. A cross-sectional evaluation of a general population comprised 939 subjects participating in the Olivetti Heart Study, with available leptin levels and WBC-and its subpopulations. WBC were significantly and positively associated with leptin, C-reactive protein and HOMA index (p < 0.05), but not with age and anthropometric indices (p > 0.05). The multivariate analysis confirmed the association between leptin and WBC, after accounting for main confounders (p < 0.05). Additional analysis on WBC subpopulations showed a positive and significant correlation between leptin and lymphocytes, monocytes and eosinophils (p < 0.05), but not with neutrophils and basophils (p > 0.05). After stratification by body weight, the positive and significant association between leptin and WBC-and its subpopulations-was found in excess body weight participants. The results of this study indicate a direct relationship between leptin levels and WBC-and its subpopulations-in excess body weight participants. These results support the hypothesis that leptin has modulatory functions on immunity and role in the pathophysiology of immune-related diseases, in particular in those associated with excess body weight.

Association of Serum Leptin and Adiponectin Concentrations with Type 2 Diabetes Biomarkers and Complications Among Saudi Women

Objective

Hyperglycemia and insulin resistance (IR) put obese women with Type 2 diabetes mellitus (T2DM) at risk for cardiovascular disease (CVD).

Methods

150 T2DM women aged 30-45 were studied cross-sectionally at Madinah Hospital lab to find T2DM risk factors and their association with adiponectin/leptin levels.

Results

Women with T2DM showed greater fasting blood glucose (FBG), hemoglobin A1c (HbA1c), triglycerides (TG), body mass index (BMI), waist circumference (WC), insulin resistance (IR), high-sensitivity C-reactive protein (hs-CRP), and CVD risk (high atherogenic index of plasma (AIP) and leptin), but decreased high-density lipoprotein (HDL-cholesterol) and poor insulin sensitivity with low adiponectin. Obese women with T2DM had increased leptin and reduced adiponectin. Leptin levels were significantly related to IR, BMI, and AIP (B= 3.97, P= 0.02) but not WC. Leptin levels were negatively correlated with insulin sensitivity (IS) and HDL-c (P< 0.05). In linear regression analysis, adiponectin levels had a significant association with IS and HDL-c (P= 0.03, P= 0.04) but an inverse relationship with IR, BMI, WC (B=-2.91, P= 0.04), and AIP (P< 0.05).

Conclusion

Increased leptin levels are related to high IR, AIP, and BMI among T2DM female patients. Similarly, adiponectin levels decrease IS and HDL-c. Therefore, obese T2DM women with high leptin and low adiponectin levels should be periodically checked to avoid or decrease consequences like CVD.

Adipokines as Diagnostic and Prognostic Markers for the Severity of COVID-19

Accumulating evidence implicates obesity as a risk factor for increased severity of disease outcomes in patients infected with severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Obesity is associated with adipose tissue dysfunction, which not only predisposes individuals to metabolic complications, but also substantially contributes to low-grade systemic inflammation, altered immune cell composition, and compromised immune function. This seems to impact the susceptibility and outcome of diseases caused by viruses, as obese people appear more vulnerable to developing infections and they recover later from infectious diseases than normal-weight individuals. Based on these findings, increased efforts to identify suitable diagnostic and prognostic markers in obese Coronavirus disease 2019 (COVID-19) patients to predict disease outcomes have been made. This includes the analysis of cytokines secreted from adipose tissues (adipokines), which have multiple regulatory functions in the body; for instance, modulating insulin sensitivity, blood pressure, lipid metabolism, appetite, and fertility. Most relevant in the context of viral infections, adipokines also influence the immune cell number, with consequences for overall immune cell activity and function. Hence, the analysis of the circulating levels of diverse adipokines in patients infected with SARS-CoV-2 have been considered to reveal diagnostic and prognostic COVID-19 markers. This review article summarizes the findings aimed to correlate the circulating levels of adipokines with progression and disease outcomes of COVID-19. Several studies provided insights on chemerin, adiponectin, leptin, resistin, and galectin-3 levels in SARS-CoV-2-infected patients, while limited information is yet available on the adipokines apelin and visfatin in COVID-19. Altogether, current evidence points at circulating galectin-3 and resistin levels being of diagnostic and prognostic value in COVID-19 disease.

The Role of Adipokines in the Pathogenesis of Psoriasis

Psoriasis is a chronic and immune-mediated skin condition characterized by pro-inflammatory cytokines and keratinocyte hyperproliferation. Dendritic cells, T lymphocytes, and keratinocytes represent the main cell subtypes involved in the pathogenesis of psoriasis, while the interleukin-23 (IL-23)/IL-17 pathway enhances the disease progression. Human adipose tissue is an endocrine organ, which secretes multiple proteins, known as adipokines, such as adiponectin, leptin, visfatin, or resistin. Current evidence highlights the immunomodulatory roles of adipokines, which may contribute to the progression or suppression of psoriasis. A better understanding of the complexity of psoriasis pathophysiology linked with adipokines could result in developing novel diagnostic or therapeutic strategies. This review aims to present the pathogenesis of psoriasis and the roles of adipokines in this process.

Prognostic roles of leptin-signaling proteins, PD-L1, and tumor-infiltrating lymphocytes in surgically-resected biliary tract cancers

BACKGROUND

Biliary tract cancers are rare, with a poor patient prognosis. Leptin and programmed death-ligand 1 (PD-L1) influence CD8⁺ and forkhead box P3 (FOXP3)⁺ lymphocytes, and thus, cancer cell growth. We aimed to define the prognostic implications of these variables and the clinicopathological features of biliary tract cancers.

METHODS

Immunohistochemistry for leptin signaling-related proteins (leptin, leptin receptor, pSTAT3, extracellular-regulated kinase, mammalian target of rapamycin), PD-L1, CD8, and FOXP3 and in situ hybridization for Epstein-Barr virus-encoded small RNAs were performed in 147 cases of surgically-resected biliary tract cancers.

RESULTS

Immune cell PD-L1-positivity, tumor size < 3 cm, adjuvant chemotherapy, no recurrence, and early-stage tumors were correlated with better 5-year survival in the tumoral PD-L1^(-) and leptin^(-) subgroups, and extrahepatic cholangiocarcinoma through multivariate analysis (all p < 0.05). Immune cell PD-L1 and adjuvant chemotherapy lost its prognostic significance in the tumoral PD-L1⁺ and leptin⁺ subgroups.

CONCLUSIONS

The prognostic implication of the variables may depend upon tumoral protein expression and the anatomical site. Immune cell PD-L1-positivity and the administration of adjuvant chemotherapy may indicate the favorable survival of patients with surgically-resected biliary tract cancers, specifically, in the tumoral PD-L1^(-) or tumor leptin^(-) subgroups and extrahepatic cholangiocarcinoma. PD-L1- or leptin-targeted therapy combined with conventional chemotherapy may benefit the tumoral PD-L1⁺ or leptin⁺ subgroups.

Leptin regulates thymic plasmacytoid dendritic cell ability to influence the thymocyte distribution in vitro

Leptin, the adipocyte-derived hormone, involved in regulating food intake and body weight, plays an important role in immunity and reproduction. Leptin signals via the specific membrane receptors expressed in most types of immune cells including dendritic cells (DCs) and thymocytes. Leptin enhances thymopoiesis and modulates T-cell-mediated immunity. Thymic plasmacytoid DCs (pDCs) are predominated in the thymus. They play an important role in thymocyte differentiation. We have analyzed whether leptin mediates its effects on human thymocytes by influencing on pDCs. We used leptin at concentration corresponding to its level during II-III trimesters of physiological pregnancy. We cultivated leptin-primed pDCs with autologous thymocytes and estimated the main thymocyte subsets expressing αβ chains of the T-cell receptor (αβTCR), natural regulatory T-cells (tTreg), natural T-helpers producing interleukin-17 (nTh17) and invariant natural killer T-cells (iNKT) in vitro. We have shown that leptin augmented CD86, CD276 expressions and depressed IL-10 productions by pDCs. Leptin-primed pDCs decreased the percentage of CD4⁺CD8⁺αβTCR⁺ thymocytes, increased CD4^hiCD8^-/loαβTCR⁺ cells. pDCs cultivated with leptin decreased the number of iNKT precursors, and did not change the number of tTreg and nTh17 precursors. Thus, leptin's important role in regulation of thymic pDC abilities to influence on the thymocyte distribution was indicated in vitro.

Association between sedentary time and plasma leptin levels in middle-aged and older adult population in Taiwan: A community-based, cross-sectional study

Background

Association of sedentary behavior and plasma leptin levels is a popular topic in recent research. Aged populations often suffer from cardiometabolic diseases, and leptin is considered a novel marker for many cardiometabolic diseases. To further explore this topic, our research investigates the relationship between sedentary time and serum leptin levels in middle-aged and older populations.

Methods

A total of 396 middle-aged and older adult Taiwanese participants were included in this study. We recorded their self-reported sitting time as sedentary time. Participants were categorized into low leptin, medium leptin group, and high leptin groups according to the tertile of serum leptin level in the study. We also analyzed the anthropometric and cardiometabolic parameters between the three groups. Spearman's correlation coefficient was used to analyze the correlation between leptin level, sedentary time, and other cardiometabolic risk factors. The relationsip between leptin and sedentary time was also shown in a scatter plot. Multivariate linear regression was performed to determine the association between serum leptin levels and sedentary time after adjusting for age, sex, alcohol consumption, smoking, triglycerides, body mass index (BMI), fasting plasma glucose, systolic blood pressure, uric acid, creatinine, and alanine transaminase (ALT).

Results

In our study, data from a total of 396 participants were analyzed. The average age of participants was 64.75 (±8.75) years, and ~41.4% were male. A longer period of sedentary time was observed in the high leptin group. A positive correlation was found between serum leptin level and sedentary time in Spearman's correlation, in all BMI groups. Serum leptin levels were positively associated with sedentary time (B = 0.603, p = 0.016) in the multivariate linear regression after adjusting for age, sex, alcohol consumption, smoking, triglycerides, BMI, fasting plasma glucose, systolic blood pressure, uric acid, creatinine, and ALT.

Conclusion

Prolonged sedentary time can be an independent risk factor for high serum leptin levels, and high leptin levels can be a novel marker in future healthcare to screen the individual with prolonged sedentary time. Furthermore, based on our study, future research can further explore the relationship between leptin levels and health promotion, especially decreasing sedentary time in the middle-aged and elder population, which is vulnerable to cardiometabolic diseases.

Intermittent fasting and immunomodulatory effects: A systematic review

Introduction

strategy of periodic food restriction and fixed eating windows, could beneficially modify individuals by losing body weight, regulating glucose or lipid metabolism, reducing blood pressure, and modulating the immune system. Specific effects of IF and its mechanisms have not yet been assessed collectively. Thus, this systematic review aims to summarize and compare clinical trials that explored the immunomodulatory effects of IF.

Methods

After screening, 28 studies were included in this systematic review.

Results

In addition to weight loss, IF could benefit health subjects by strengthening their circadian rhythms, migrating immune cells, lower inflammatory factors, and enriching microbials. In addition of the anti-inflammatory effect by regulating macrophages, protection against oxidative stress with hormone secretion and oxidative-related gene expression plays a key beneficial role for the influence of IF on obese subjects.

Discussion

Physiological stress by surgery and pathophysiological disorders by endocrine diseases may be partly eased with IF. Moreover, IF might be used to treat anxiety and cognitive disorders with its cellular, metabolic and circadian mechanisms. Finally, the specific effects of IF and the mechanisms pertaining to immune system in these conditions require additional studies.

Role of Leptin as a Link between Asthma and Obesity: A Systematic Review and Meta-Analysis

Asthma and obesity are considered as highly prevalent diseases with a great impact on public health. Obesity has been demonstrated to be an aggravating factor in the pathogenesis of asthma. Adipose tissue secretes proinflammatory cytokines and mediators, including leptin, which may promote the development and severity of asthma in obese patients. This study is a systematic review and a meta-analysis based on the relationship between leptin and asthma during obesity. MEDLINE, Cochrane, EMBASE and CINAHL databases were used. Data heterogeneity was analyzed using Cochran’s Q and treatment effect with the DerSimonian and Laird method. Random effect analyses were carried out to test data sensitivity. Asymmetry was estimated using Begg’s and Egger’s tests. All studies showed significant differences in leptin levels. The effect of the measures (p < 0.001), data sensitivity (p < 0.05) and data asymmetry were statistically significant, as well as tBegg’s test (p = 0.010) and Egge’s test (p < 0.001). Despite the existing limiting factors, the results of this study support the relevant role of leptin in the pathophysiology of asthma in obese subjects. Nevertheless, further studies are needed to obtain better insight in the relationship between leptin and asthma in obesity.

Relationship among Body Composition, Adipocytokines, and Irisin on Exercise Capacity and Quality of Life in COPD: A Pilot Study

Adipose tissue is an endocrine organ that interferes with the severity of chronic obstructive pulmonary disease (COPD). Although inflammatory markers, body composition, and nutritional status have a significant impact on pulmonary function, the real contribution of adipocytokines and myokines in COPD is still controversial. We aimed to evaluate the role played by the body composition, leptin, adiponectin, haptoglobin, and irisin on the functional exercise capacity, respiratory function, and quality of life (QoL) in COPD. In 25 COPD (20% GOLD-1; 60% GOLD-2; 20% GOLD-3) patients and 26 matched control subjects, we find that leptin, total adiponectin and haptoglobin are significantly increased whereas the 6 min walk test (6MWT) and physical functioning scores are significantly decreased in COPD versus controls. A significant positive relationship is found between leptin and fat mass and between 6MWT and the good health indicators of nutritional status. A significant inverse relationship is found between 6MWT and leptin and fat mass, FEV₁ and haptoglobin, and irisin and haptoglobin. Phase angle and leptin level are significant predictors for functional exercise capacity assessed with 6MWT. Taken altogether, the results of this pilot study further support the role played by body composition and adipocytokines on exercise capacity respiratory function and QoL in COPD.

Effectiveness and safety of different academic schools of traditional Chinese medicine in the treatment of obesity: A protocol for systematic review and meta-analysis

BACKGROUND

Obesity is a global epidemic. Since 1975, the global obesity rate has almost tripled. Although many systematic reviews and clinical trials have shown that traditional Chinese medicine (TCM) can effectively treat obesity, the effectiveness and safety of different academic schools of TCM in treating obesity have not been systematically evaluated.

METHODS

The retrieval language of this study was Chinese and English. From the date of creation of the following data to June 2023, the data of Medline, PubMed, Embase, Cochrane Science Network, China Biomedical Literature Database, Central Controlled Trial Registration Center, and China Science Journal Database were retrieved, respectively. This study included clinical randomized controlled trials related to the treatment of obesity by different academic schools of TCM. The main outcome measures were body mass index, waist circumference, hip circumference, waist hip ratio, body fat content, fasting blood glucose, glycosylated hemoglobin, and blood lipid level. In addition, we manually searched other resources, including reference lists of identified publications, conference articles, and gray literature.

RESULTS

This study will provide a more diverse choice of treatment options.

CONCLUSION

The purpose of this study is to summarize and evaluate the effectiveness and safety of different academic schools of TCM in improving and treating obese patients from clinical trials, so as to provide more options for obesity treatment.

Obesity and Risk for Lymphoma: Possible Role of Leptin

Obesity, which is considered a pandemic due to its high prevalence, is a risk factor for many types of cancers, including lymphoma, through a variety of mechanisms by promoting an inflammatory state. Specifically, over the last few decades, obesity has been suggested not only to increase the risk of lymphoma but also to be associated with poor clinical outcomes and worse responses to different treatments for those diseases. Within the extensive range of proinflammatory mediators that adipose tissue releases, leptin has been demonstrated to be a key adipokine due to its pleotropic effects in many physiological systems and diseases. In this sense, different studies have analyzed leptin levels and leptin/leptin receptor expressions as a probable bridge between obesity and lymphomas. Since both obesity and lymphomas are prevalent pathophysiological conditions worldwide and their incidences have increased over the last few years, here we review the possible role of leptin as a promising proinflammatory mediator promoting lymphomas.

A new perspective: Fat tissue and adipokines in rheumatic heart valves

OBJECTIVE

To observe fat tissue and the expression of adipokines in rheumatic heart valves and explore the possible role of fat tissue and adipokines in the pathology of rheumatic heart disease (RHD).

METHODS

In this retrospective study, a total of 29 patients who received mitral valve replacement surgery were included. The study group consisted of 25 patients with RHD while the control group consisted of 4 patients with secondary mitral insufficiency caused by coronary heart disease (CAD). The clinical data of the patients including medical history, age, body mass index (BMI), fasting blood glucose (FBG), total triglycerides (TG), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), apolipoprotein(a) [apo(a)], apolipoprotein(b) [apo(b)] were collected and compared. Cardiac ultrasonography was used to assess valve conditions before surgery. The removed valves were collected. The hematoxylin-eosin (HE) staining, oil-red O staining, and Masson's trichrome staining were adopted to evaluate the histological changes in the mitral valve. Immunohistochemical (IMC) staining was performed to evaluate the expression of adiponectin, leptin, and chemerin.

RESULTS

There was no significant difference in general information and blood lipid levels between the two groups (all p > .05). Preoperative ultrasonography showed adipose tissue in the mitral valve of RHD patients. In the study group, rheumatic mitral valve samples showed thickening, adherence at the junction of the leaflets, calcification, and yellowish or fat mass by naked observation. The HE staining showed that there was calcification, inflammatory cell infiltration, fibrous tissue arranged disorder, and neovascularization. The oil-red O staining suggested fatty infiltration. Masson's trichrome staining suggested disorderly arrangement of collagen fiber and elastic fiber in rheumatic lesions, and the lesions were dominated by collagen fiber hyperplasia and less elastic fiber hyperplasia. The results of IMC indicated that chemerin was not expressed in valves of the control group. Most of the valve samples from the study group also did not show leptin and the leptin was seen in only a few rheumatic mitral valves with vascular hyperplasia. Adiponectin was not found in the valves of the study group and the control group.

CONCLUSION

Adipose tissue in the rheumatic mitral valve could be observed by ultrasound. The fat mass and adipokines existed in rheumatic mitral valves, the adipocytokine chemerin is involved in the progression of the pathology in RHD.

The Role of Adipokines in Inflammatory Mechanisms of Obesity

Adipokines are currently widely studied cellular signaling proteins produced by adipose tissue and involved in various processes, including inflammation; energy and appetite modulation; lipid and glucose metabolism; insulin sensitivity; endothelial cell functioning; angiogenesis; the regulation of blood pressure; and hemostasis. The current review attempted to highlight the key functions of adipokines in the inflammatory mechanisms of obesity, its complications, and its associated diseases. An extensive search for materials on the role of adipokines in the pathogenesis of obesity was conducted online using the PubMed and Scopus databases until October 2022.

Adipose tissue-to-breast cancer crosstalk: Comprehensive insights

The review focuses on mechanistic evidence for the link between obesity and breast cancer. According to the IARC study, there is sufficient evidence that obesity is closely related to a variety of cancers. Among them, breast cancer is particularly disturbed by adipose tissue due to the unique histological structure of the breast. The review introduces the relationship between obesity and breast cancer from two aspects, including factors that promote tumorigenesis or metastasis. We summarize alterations in adipokines and metabolic pathways that contribute to breast cancer development. Breast cancer metastasis is closely related to obesity-induced pro-inflammatory microenvironment, adipose stem cells, and miRNAs. Based on the mechanism by which obesity causes breast cancer, we list possible therapeutic directions, including reducing the risk of breast cancer and inhibiting the progression of breast cancer. We also discussed the risk of autologous breast remodeling and fat transplantation. Finally, the causes of the obesity paradox and the function of enhancing immunity are discussed. Evaluating the balance between obesity-induced inflammation and enhanced immunity warrants further study.

Square wave voltammetric approach to leptin immunosensing and optimization of driving parameters with chemometrics

Square wave voltammetry serves as an effective analytical means to evaluate antigen-antibody coupling at the solid-liquid interface. Herein, we describe 3-aminopropyltrimethoxysilane (APTMS) induced irreversible immobilization of anti-leptin to micellar gold nanoparticles (AuNPs). Antibodies (Abs) were orthogonally loaded on micellized AuNP assemblies via amino residual groups. The ratio of bound Ab molecules was determined by the Bradford assay. The AuNP/Ab layer modified electrodes with variable antibody surface coverage (∼400 ± 55-200 ± 30 Ab/NP) were analyzed in terms of change in backward, net current (Ip) components. The rate of antigen coupling was found to be consistent with the variation in antibody density as well as the binding affinity. The lowest detection limit was observed at the femtomolar level (0.25 fM/mL) over a wide range of antigen concentration (6.2 ng/mL to 0.12 fg/mL). The variables affecting the epitope-paratope interaction were further optimized using a chemometric approach and a response surface methodology (RSM).

A Sedentary and Unhealthy Lifestyle Fuels Chronic Disease Progression by Changing Interstitial Cell Behaviour: A Network Analysis

Managing chronic diseases, such as heart disease, stroke, diabetes, chronic lung disease and Alzheimer’s disease, account for a large proportion of health care spending, yet they remain in the top causes of premature mortality and are preventable. It is currently accepted that an unhealthy lifestyle fosters a state of chronic low-grade inflammation that is linked to chronic disease progression. Although this is known to be related to inflammatory cytokines, how an unhealthy lifestyle causes cytokine release and how that in turn leads to chronic disease progression are not well known. This article presents a theory that an unhealthy lifestyle fosters chronic disease by changing interstitial cell behavior and is supported by a six-level hierarchical network analysis. The top three networks include the macroenvironment, social and cultural factors, and lifestyle itself. The fourth network includes the immune, autonomic and neuroendocrine systems and how they interact with lifestyle factors and with each other. The fifth network identifies the effects these systems have on the microenvironment and two types of interstitial cells: macrophages and fibroblasts. Depending on their behaviour, these cells can either help maintain and restore normal function or foster chronic disease progression. When macrophages and fibroblasts dysregulate, it leads to chronic low-grade inflammation, fibrosis, and eventually damage to parenchymal (organ-specific) cells. The sixth network considers how macrophages change phenotype. Thus, a pathway is identified through this hierarchical network to reveal how external factors and lifestyle affect interstitial cell behaviour. This theory can be tested and it needs to be tested because, if correct, it has profound implications. Not only does this theory explain how chronic low-grade inflammation causes chronic disease progression, it also provides insight into salutogenesis, or the process by which health is maintained and restored. Understanding low-grade inflammation as a stalled healing process offers a new strategy for chronic disease management. Rather than treating each chronic disease separately by a focus on parenchymal pathology, a salutogenic strategy of optimizing interstitial health could prevent and mitigate multiple chronic diseases simultaneously.

Type 2 Diabetes Mellitus: Pathogenic Features and Experimental Models in Rodents

Type 2 diabetes mellitus (T2DM) is the most common endocrine disorder (90%) in the world; it has numerous clinical, immunological, and genetic differences from type 1 diabetes mellitus. The pathogenesis of T2DM is complex and not fully clear. To date, animal models remain the main tool by which to study the pathophysiology and therapy of T2DM. Rodents are considered the best choice among animal models, because they are characterized by a small size, short induction period, easy diabetes induction, and economic efficiency. This review summarizes data on experimental models of T2DM that are currently used, evaluates their advantages and disadvantages vis-a-vis research, and describes in detail the factors that should be taken into account when using these models. Selection of a suitable model for tackling a particular issue is not always trivial; it affects study results and their interpretation.

Protective Effects of High-Fat Diet against Murine Colitis in Association with Leptin Signaling and Gut Microbiome

Inflammatory bowel disease (IBD) is characterized by chronic intestinal-tract inflammation with dysregulated immune responses, which are partly attributable to dysbiosis. Given that diet plays a critical role in IBD pathogenesis and progression, we elucidated the effects of a high-fat diet (HFD) feeding on IBD development in relation to immune dysfunction and the gut microbiota. Five-week-old male C57BL/6J mice were fed either a normal diet (ND) or HFD for 14 weeks. The animals were further divided into ND, ND+ dextran sulfate sodium (DSS), HFD, and HFD+DSS treatment groups. The HFD+DSS mice exhibited lower body weight loss, lower disease activity index, longer colon length, and increased tight-junction protein expression and goblet-cell proportions compared with the ND+DSS mice. The T helper (h)1 and Th17 cell populations and pro-inflammatory cytokines involved in colitis pathogenesis were significantly more reduced in the HFD+DSS mice than in the ND+DSS mice. The HFD+DSS mice showed significantly increased serum leptin concentrations, colonic leptin receptor expression, enhanced anti-apoptotic AKT expression, and reduced pro-apoptotic MAPK and Bax expression compared with the ND+DSS mice, suggesting the involvement of the leptin-mediated pathway in intestinal epithelial cell apoptosis. The alterations in the gut-microbiota composition in the HFD+DSS group were the opposite of those in the ND+DSS group and rather similar to those of the ND group, indicating that the protective effects of HFD feeding against DSS-induced colitis are associated with changes in gut-microbiota composition. Overall, HFD feeding ameliorates DSS-induced colitis and colonic mucosal damage by reinforcing colonic barrier function and regulating immune responses in association with changes in gut-microbiota composition.

Quercetin ameliorates salivary gland apoptosis and inflammation in primary Sjögren's syndrome through regulation of the leptin/OB-R signaling

Dry mouth is the main manifestation of Sjögren syndrome (SS). Quercetin has been reported to alleviate radiation-induced salivary gland damage, yet the effect of quercetin on SS-caused salivary gland damage remains unclear. This study aimed to investigate the effects of quercetin on SS-induced salivary gland damage and the mechanism underlying its therapeutic potential in SS. Here, NOD/Ltj mice were used to spontaneously mimic SS-induced salivary gland inflammation in vivo and salivary gland epithelial cells (SGECs) were stimulated by interferon-γ (IFN-γ) to mimic cell inflammation in vitro. Results showed that quercetin significantly reduced loss of saliva flow, salivary gland damage, cell apoptosis, and inflammatory response in NOD/Ltj mice. Quercetin treatment also significantly reduced the increased serum leptin (LP) levels in NOD/Ltj mice. Furthermore, quercetin blocked the increases in the expression of obesity receptor (OB-R) and its downstream Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling in the salivary glands. In vitro experiments confirmed that quercetin could protect SGECs from IFN-γ-induced cell apoptosis and inflammation through the LP/OB-R-activated JAK2/STAT3 signaling. Hence, quercetin might protect against SS-induced salivary gland damage by relieving cell apoptosis and inflammation by inhibiting the LP/OB-R signaling, providing a new perspective for treating SS-induced dry mouth.

Inflammation and Gastric Cancer

Gastric cancer remains a major killer globally, although its incidence has declined over the past century. It is the fifth most common cancer and the third most common reason for cancer-related deaths worldwide. Gastric cancer is the outcome of a complex interaction between environmental, host genetic, and microbial factors. There is significant evidence supporting the association between chronic inflammation and the onset of cancer. This association is particularly robust for gastrointestinal cancers in which microbial pathogens are responsible for the chronic inflammation that can be a triggering factor for the onset of those cancers. Helicobacter pylori is the most prominent example since it is the most widespread infection, affecting nearly half of the world’s population. It is well-known to be responsible for inducing chronic gastric inflammation progressing to atrophy, metaplasia, dysplasia, and eventually, gastric cancer. This review provides an overview of the association of the factors playing a role in chronic inflammation; the bacterial characteristics which are responsible for the colonization, persistence in the stomach, and triggering of inflammation; the microbiome involved in the chronic inflammation process; and the host factors that have a role in determining whether gastritis progresses to gastric cancer. Understanding these interconnections may improve our ability to prevent gastric cancer development and enhance our understanding of existing cases.