Chemokine Expression in Neutrophils and Subcutaneous Adipose Tissue Cells Obtained during Abdominoplasty from Patients with Obesity and Normal Body Weight

Metabolic regulation of the immune system in health and diseases: mechanisms and interventions

Metabolism, including glycolysis, oxidative phosphorylation, fatty acid oxidation, and other metabolic pathways, impacts the phenotypes and functions of immune cells. The metabolic regulation of the immune system is important in the pathogenesis and progression of numerous diseases, such as cancers, autoimmune diseases and metabolic diseases. The concept of immunometabolism was introduced over a decade ago to elucidate the intricate interplay between metabolism and immunity. The definition of immunometabolism has expanded from chronic low-grade inflammation in metabolic diseases to metabolic reprogramming of immune cells in various diseases. With immunometabolism being proposed and developed, the metabolic regulation of the immune system can be gradually summarized and becomes more and more clearer. In the context of many diseases including cancer, autoimmune diseases, metabolic diseases, and many other disease, metabolic reprogramming occurs in immune cells inducing proinflammatory or anti-inflammatory effects. The phenotypic and functional changes of immune cells caused by metabolic regulation further affect and development of diseases. Based on experimental results, targeting cellular metabolism of immune cells becomes a promising therapy. In this review, we focus on immune cells to introduce their metabolic pathways and metabolic reprogramming, and summarize how these metabolic pathways affect immune effects in the context of diseases. We thoroughly explore targets and treatments based on immunometabolism in existing studies. The challenges of translating experimental results into clinical applications in the field of immunometabolism are also summarized. We believe that a better understanding of immune regulation in health and diseases will improve the management of most diseases.

Involvement of the Macrophage Migration Inhibitory Factor (MIF) in Lipedema

Lipedema is a chronic disorder that mainly affects women. It is often misdiagnosed, and its etiology remains unknown. Recent research indicates an accumulation of macrophages and a shift in macrophage polarization in lipedema. One known protein superfamily that contributes to macrophage accumulation and polarization is the macrophage migration inhibitory factor (MIF) family. MIF-1 and MIF-2 are ubiquitously expressed and also regulate inflammatory processes in adipose tissue. In this study, the expression of MIF-1, MIF-2 and CD74-a common receptor for both cytokines-was analyzed in tissue samples of 11 lipedema and 11 BMI-matched, age-matched and anatomically matched control patients using qPCR and immunohistochemistry (IHC). The mRNA expression of MIF-1 (mean 1.256; SD 0.303; p = 0.0485) and CD74 (mean 1.514; SD 0.397; p = 0.0097) were significantly elevated in lipedema patients, while MIF-2 expression was unaffected (mean 1.004; SD 0.358; p = 0.9718). The IHC analysis corroborated the results for CD74 expression on a cellular level. In conclusion, our results provide first evidence for a potential involvement of the MIF family, presumably via the MIF-1-CD74 axis, in lipedema.

Central regulation of stress-evoked peripheral immune responses

Stress-linked psychiatric disorders, including anxiety and major depressive disorder, are associated with systemic inflammation. Recent studies have reported stress-induced alterations in haematopoiesis that result in monocytosis, neutrophilia, lymphocytopenia and, consequently, in the upregulation of pro-inflammatory processes in immunologically relevant peripheral tissues. There is now evidence that this peripheral inflammation contributes to the development of psychiatric symptoms as well as to common co-morbidities of psychiatric disorders such as metabolic syndrome and immunosuppression. Here, we review the specific brain and spinal regions, and the neuronal populations within them, that respond to stress and transmit signals to peripheral tissues via the autonomic nervous system or neuroendocrine pathways to influence immunological function. We comprehensively summarize studies that have employed retrograde tracing to define neurocircuits linking the brain to the bone marrow, spleen, gut, adipose tissue and liver. Moreover, we highlight studies that have used chemogenetic or optogenetic manipulation or intracerebroventricular administration of peptide hormones to control somatic immune responses. Collectively, this growing body of literature illustrates potential mechanisms through which stress signals are conveyed from the CNS to immune cells to regulate stress-relevant behaviours and comorbid pathophysiology.

Neutrophils and their role in the aetiopathogenesis of type 1 and type 2 diabetes

Multiple and complex aetiological processes underlie diabetes mellitus, which invariably result in the development of hyperglycaemia. Although there are two prevalent distinct forms of the disease, that is, type 1 and type 2 diabetes, accumulating evidence indicates that these syndromes share more aetiopathological mechanisms than originally thought. This compels a rethinking of the approaches to prevent and treat the different manifestations of what eventually becomes a hyperglycaemic state. This review aims to address the involvement of neutrophils, the most abundant type of granulocytes involved in the initiation of the acute phase of inflammation, in the aetiopathogenesis of diabetes mellitus, with a focus on type 1 and type 2 diabetes. We review the evidence that neutrophils are the first leucocytes to react to and accumulate inside target tissues of diabetes, such as the pancreas and insulin-sensitive tissues. We then review available data on the role of neutrophils and their functional alteration, with a focus on NETosis, in the progression towards clinical disease. Finally, we review potential approaches as secondary and adjunctive treatments to limit neutrophil-mediated damage in the prevention of the progression of subclinical disease to clinical hyperglycaemia.

Serum levels of inflammatory markers and HbA1c in patients with type 2 diabetes and apical periodontitis: Preliminary findings

This pilot study assessed the glycaemic control and the serum levels of inflammatory mediators in type 2 diabetes (T2DM) patients with apical periodontitis (AP). Thirty individuals were divided into four groups: Healthy (H); with AP (AP); with T2DM (T2DM); and with T2DM and AP (T2DM-AP). Demographic and pharmacological data were registered. The body mass index (BMI) and the levels of glycated haemoglobin (HbA1c) and IL-1β, IL-6, IL-10, CCL3 and CCL4 were evaluated. AP areas were determined radiographically. Mean age was 64 ± 12 years, with 63% females. Most T2DM patients were under treatment with metformin and antihypertensives. BMI and H1bAc were significantly higher in T2DM patients in relation to H and AP groups. The AP areas were larger in the T2DM-AP group, compared with the AP group. These preliminary findings suggest no influence of AP on glycaemic control or inflammatory levels amongst T2DM patients, although T2DM increased the AP severity.

Melanoma Progression under Obesity: Focus on Adipokines

Simple Summary

Obesity is a rapidly growing public health problem and the reason for numerous diseases in the human body, including cancer. This article reviews the current knowledge of the effect of molecules secreted by adipose tissue-adipokines on melanoma progression. We also discuss the role of these factors as markers of incidence, metastasis, and melanoma patient survival. Understanding the functions of adipokines will lead to knowledge of whether and how obesity promotes melanoma growth.

Abstract

Obesity is a growing problem in the world and is one of the risk factors of various cancers. Among these cancers is melanoma, which accounts for the majority of skin tumor deaths. Current studies are looking for a correlation between obesity and melanoma. They suspect that a potential cause of its development is connected to the biology of adipokines, active molecules secreted by adipose tissue. Under physiological conditions, adipokines control many processes, including lipid and glucose homeostasis, insulin sensitivity, angiogenesis, and inflammations. However, when there is an increased amount of fat in the body, their secretion is dysregulated. This article reviews the current knowledge of the effect of adipokines on melanoma growth. This work focuses on the molecular pathways by which adipose tissue secreted molecules modify the angiogenesis, migration, invasion, proliferation, and death of melanoma cells. We also discuss the role of these factors as markers of incidence, metastasis, and melanoma patient survival. Understanding the functions of adipokines will lead to knowledge of whether and how obesity promotes melanoma growth. Further studies may contribute to the innovations of therapies and the use of adipokines as predictive and/or prognostic biomarkers.

Sex Differences in Macrophage Responses to Obesity-Mediated Changes Determine Migratory and Inflammatory Traits

The mechanisms whereby obesity differentially affects males and females are unclear. Because macrophages are functionally the most important cells in obesity-induced inflammation, we sought to determine reasons for male-specific propensity in macrophage migration. We previously determined that male mice fed a high-fat diet exhibit macrophage infiltration into the hypothalamus, whereas females were protected irrespective of ovarian estrogen, in this study, we show that males accumulate more macrophages in adipose tissues that are also more inflammatory. Using bone marrow cells or macrophages differentiated in vitro from male and female mice fed control or high-fat diet, we demonstrated that macrophages derived from male mice are intrinsically more migratory. We determined that males have higher levels of leptin in serum and adipose tissue. Serum CCL2 levels, however, are the same in males and females, although they are increased in obese mice compared with lean mice of both sexes. Leptin receptor and free fatty acid (FFA) receptor, GPR120, are upregulated only in macrophages derived from male mice when cultured in the presence of FFA to mimic hyperlipidemia of obesity. Unless previously stimulated with LPS, CCL2 did not cause migration of macrophages. Leptin, however, elicited migration of macrophages from both sexes. Macrophages from male mice maintained migratory capacity when cultured with FFA, whereas female macrophages failed to migrate. Therefore, both hyperlipidemia and hyperleptinemia contribute to male macrophage-specific migration because increased FFA induce leptin receptors, whereas higher leptin causes migration. Our results may explain sex differences in obesity-mediated disorders caused by macrophage infiltration.