Direct reciprocal effects of resistin and adiponectin on vascular endothelial cells: a new insight into adipocytokine-endothelial cell interactions

Serum Adiponectin Levels Increase in Acute Ischemic Stroke and Correlate with Patients' Outcomes: A Pilot Study

Stroke is a leading cause of death and severe disability worldwide. Rapid diagnosis is critical to ensure the timely administration of medical treatment. Given that in some cases CT scans fail to show the classic clinical signs of stroke, we aimed to evaluate the diagnostic capacity of adiponectin levels and their association with the clinical parameters of patients with acute ischemic stroke (AIS). Adiponectin was measured within 24 h (T1) and 48 h (T2) of AIS onset in 70 patients. A total of 68 control cases were included in the study. Adiponectin levels were significantly higher in the AIS patients than in the controls (16.64 (3.79; 16.69) vs. 3.78 (3.79; 16.69); p < 0.001), with an accuracy of 0.98 (AUC = 0.99). Lower levels were seen in males and in AIS patients with obesity. Higher levels of adiponectin at T1 were associated with a moderate/severe NIHSS score at patient discharge. Moreover, higher levels of borderline significance were seen in patients who died within 12 months of their AIS episode (p = 0.054). Adiponectin may be a useful biomarker for the identification of AIS patients who do not present classic CT signs and could be used to stratify severe cases. Further studies are needed to validate these results.

Proteomics approach for biomarker discovery in Kawasaki disease

INTRODUCTION

Kawasaki disease (KD) is a medium vessel vasculitis mainly affecting children below the age of 5. KD is the leading cause of acquired heart disease in developed countries. Diagnosis of KD is clinical, and there are no pathognomonic laboratory tests to confirm the diagnosis. There is a paucity of studies that have utilized proteomic approach for biomarker discovery in KD. Identification of these biomarkers may be helpful for early and more effective diagnosis and may aid in the treatment of KD.

AREA COVERED

The present review focuses on studies that have utilized the proteomic approach in the identification of biomarkers in patients with KD. We have divided these biomarkers into three different categories: the biomarkers used for (a) assessment of risk of KD; (b) assessment of risk of coronary artery aneurysms; and (c) assessment of treatment resistance.

EXPERT OPINION

Efforts to improve the clinical and diagnostic evaluation of KD have focused on general markers of inflammation that are not specific for KD. Identification of a proteomic-based biomarker can reliably and specifically differentiate KD from other diseases and could help in the prompt diagnosis. Comprehensive analysis of the serum proteome of patients with KD may be helpful in identifying candidate protein biomarkers.

The Complex Immunological Alterations in Patients with Type 2 Diabetes Mellitus on Hemodialysis

It is widely known that diabetes mellitus negatively impacts both the innate immunity (the inflammatory response) and the acquired immunity (the humoral and cellular immune responses). Many patients with diabetes go on to develop chronic kidney disease, which will necessitate hemodialysis. In turn, long-term chronic hemodialysis generates an additional chronic inflammatory response and impairs acquired immunity. The purpose of this paper is to outline and compare the mechanisms that are the basis of the constant aggression towards self-components that affects patients with diabetes on hemodialysis, in order to find possible new therapeutic ways to improve the functionality of the immune system. Our study will take a detailed look at the mechanisms of endothelial alteration in diabetes and hemodialysis, at the mechanisms of inflammatory generation and signaling at different levels and also at the mechanisms of inflammation-induced insulin resistance. It will also discuss the alterations in leukocyte chemotaxis, antigen recognition and the dysfunctionalities in neutrophils and macrophages. Regarding acquired immunity, we will outline the behavioral alterations of T and B lymphocytes induced by diabetes mellitus and chronic hemodialysis.

Adipose tissue as a therapeutic target for vascular damage in Alzheimer's disease

Adipose tissue has recently been recognized as an important endocrine organ that plays a crucial role in energy metabolism and in the immune response in many metabolic tissues. With this regard, emerging evidence indicates that an important crosstalk exists between the adipose tissue and the brain. However, the contribution of adipose tissue to the development of age-related diseases, including Alzheimer's disease, remains poorly defined. New studies suggest that the adipose tissue modulates brain function through a range of endogenous biologically active factors known as adipokines, which can cross the blood-brain barrier to reach the target areas in the brain or to regulate the function of the blood-brain barrier. In this review, we discuss the effects of several adipokines on the physiology of the blood-brain barrier, their contribution to the development of Alzheimer's disease and their therapeutic potential. LINKED ARTICLES: This article is part of a themed issue From Alzheimer's Disease to Vascular Dementia: Different Roads Leading to Cognitive Decline. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.6/issuetoc.

Predictive value of adipokines for the severity of acute pancreatitis: a meta-analysis

BACKGROUND

Severe acute pancreatitis (SAP) is a dangerous condition with a high mortality rate. Many studies have found an association between adipokines and the development of SAP, but the results are controversial. Therefore, we performed a meta-analysis of the association of inflammatory adipokines with SAP.

METHODS

We screened PubMed, EMBASE, Web of Science and Cochrane Library for articles on adipokines and SAP published before July 20, 2023. The quality of the literature was assessed using QUADAS criteria. Standardized mean differences (SMD) with 95% confidence intervals (CI) were calculated to assess the combined effect. Subgroup analysis, sensitivity analysis and publication bias tests were also performed on the information obtained.

RESULT

Fifteen eligible studies included 1332 patients with acute pancreatitis (AP). Pooled analysis showed that patients with SAP had significantly higher serum levels of resistin (SMD = 0.78, 95% CI:0.37 to 1.19, z = 3.75, P = 0.000). The difference in leptin and adiponectin levels between SAP and mild acute pancreatitis (MAP) patients were not significant (SMD = 0.30, 95% CI: -0.08 to 0.68, z = 1.53, P = 0.127 and SMD = 0.11, 95% CI: -0.17 to 0.40, z = 0.80, P = 0.425, respectively). In patients with SAP, visfatin levels were not significantly different from that in patients with MAP (SMD = 1.20, 95% CI: -0.48 to 2.88, z = 1.40, P = 0.162).

CONCLUSION

Elevated levels of resistin are associated with the development of SAP. Resistin may serve as biomarker for SAP and has promise as therapeutic target.

Imbalance of helper T cell subtypes and adipokine secretion in perivascular adipose tissue as a trigger of atherosclerosis in chronic Porphyromonas gingivalis W83 infection

Periodontal disease, a prevalent oral disease, is an independent risk factor for atherosclerosis. Porphyromonas gingivalis (P.g), a keystone pathogen of periodontal disease, contributes to the pathogenesis of atherosclerosis. However, the exact mechanism remains unclear. An increasing number of studies have proposed the atherogenic influence of perivascular adipose tissue (PVAT) in pathological conditions including hyperlipidemia and diabetes. Nevertheless, the role of PVAT in atherosclerosis promoted by P.g infection has not been explored. In our study, we investigated the association between P.g colonization in PVAT and progression of atherosclerosis through experiments on clinical samples. We further investigated P.g invasion of PVAT, PVAT inflammation, aortic endothelial inflammation, aortic lipid deposition, and systemic inflammation in C57BL/6 J mice with or without P.g infection at 20, 24, and 28 weeks of age. PVAT inflammation, characterized by imbalance in Th1/Treg and dysregulated adipokine levels, was associated with P.g invasion, preceding endothelial inflammation that occurred independently of its direct invasion. The phenotype of systemic inflammation coincided with that of PVAT inflammation, but systemic inflammation occurred after endothelial inflammation. Therefore PVAT inflammation in early atherosclerosis could be a primary trigger of aortic endothelial inflammation and lipid deposition in chronic P.g infection, through the dysregulated paracrine secretion of T helper-1-related adipokines.

Positive association between serum resistin and smoking was strongest in homozygotes of the G-A haplotype at c.-420 C>G and c.-358 G>A in RETN promoter: the Toon Genome Study

Resistin is mainly expressed in human monocytes/macrophages and is associated with insulin resistance, inflammation, and atherosclerosis. Serum resistin is strongly correlated with the G-A haplotype defined by single nucleotide polymorphisms (SNPs) c.-420 C>G (SNP-420) (rs1862513) and c.-358 G>A (SNP-358) (rs3219175) in the promoter region of the human resistin gene (RETN). Smoking is also associated with insulin resistance. We investigated the association between smoking and serum resistin and the effect of the G-A haplotype on this association. Participants were recruited under the Toon Genome Study (an observational epidemiology research in the Japanese population). Of these, 1975 subjects genotyped for both SNP-420 and SNP-358 were analyzed for serum resistin by grouping them based on smoking status and G-A haplotype status. RETN mRNA, isolated from whole blood cells, was evaluated in smokers (n = 7) and age-, sex-, and BMI-matched non-smokers (n = 7) with the G-A haplotype homozygotes. Serum resistin tended to be higher in current smokers who smoked more cigarettes per day (P for trend < 0.0001). The positive association between serum resistin and smoking was strongest in the G-A haplotype homozygotes, followed by heterozygotes and non-carriers (interaction P < 0.0001). This positive association was stronger in the G-A homozygotes than the C-G homozygotes (interaction P < 0.0001). RETN mRNA was 1.40-fold higher in smokers than non-smokers with the G-A homozygotes (P = 0.022). Therefore, the positive association between serum resistin and smoking was strongest in the G-A haplotype homozygotes defined by RETN SNP-420 and SNP-358.

Adipokines in atherosclerosis: unraveling complex roles

Adipokines are biologically active factors secreted by adipose tissue that act on local and distant tissues through autocrine, paracrine, and endocrine mechanisms. However, adipokines are believed to be involved in an increased risk of atherosclerosis. Classical adipokines include leptin, adiponectin, and ceramide, while newly identified adipokines include visceral adipose tissue-derived serpin, omentin, and asprosin. New evidence suggests that adipokines can play an essential role in atherosclerosis progression and regression. Here, we summarize the complex roles of various adipokines in atherosclerosis lesions. Representative protective adipokines include adiponectin and neuregulin 4; deteriorating adipokines include leptin, resistin, thrombospondin-1, and C1q/tumor necrosis factor-related protein 5; and adipokines with dual protective and deteriorating effects include C1q/tumor necrosis factor-related protein 1 and C1q/tumor necrosis factor-related protein 3; and adipose tissue-derived bioactive materials include sphingosine-1-phosphate, ceramide, and adipose tissue-derived exosomes. However, the role of a newly discovered adipokine, asprosin, in atherosclerosis remains unclear. This article reviews progress in the research on the effects of adipokines in atherosclerosis and how they may be regulated to halt its progression.

Perivascular Adipose Tissue Oxidative Stress in Obesity

Perivascular adipose tissue (PVAT) adheres to most systemic blood vessels in the body. Healthy PVAT exerts anticontractile effects on blood vessels and further protects against cardiovascular and metabolic diseases. Healthy PVAT regulates vascular homeostasis via secreting an array of adipokine, hormones, and growth factors. Normally, homeostatic reactive oxygen species (ROS) in PVAT act as secondary messengers in various signalling pathways and contribute to vascular tone regulation. Excessive ROS are eliminated by the antioxidant defence system in PVAT. Oxidative stress occurs when the production of ROS exceeds the endogenous antioxidant defence, leading to a redox imbalance. Oxidative stress is a pivotal pathophysiological process in cardiovascular and metabolic complications. In obesity, PVAT becomes dysfunctional and exerts detrimental effects on the blood vessels. Therefore, redox balance in PVAT emerges as a potential pathophysiological mechanism underlying obesity-induced cardiovascular diseases. In this review, we summarise new findings describing different ROS, the major sources of ROS and antioxidant defence in PVAT, as well as potential pharmacological intervention of PVAT oxidative stress in obesity.

Obesity and diabetes

Obesity, which has currently reached pandemic dimensions, is usually accompanied by diabetes mellitus type 2 (T2DM). These two conditions share common pathophysiological mechanisms. Adipose tissue secretes cytokines which are involved in inflammation and various endocrine functions. As for T2DM, it is characterized also by inflammation, mitochondrial dysfunction, and hyperinsulinemia. These conditions occur also in other diseases related to obesity and T2DM, like cardiovascular disease (CVD) and nonalcoholic fatty liver disease (NAFLD). Thus, management of obesity-related complications with lifestyle modification, anti-obesity drugs, and bariatric surgery, all contribute to improvement in any of these conditions. This review provides an overview of the literature addressing the association between obesity and T2DM, briefly discussing the pathophysiological mechanisms linking these conditions and outlining the management approach at the overlap of obesity and T2DM.

Temperature-Dependent Effects of Eicosapentaenoic Acid (EPA) on Browning of Subcutaneous Adipose Tissue in UCP1 Knockout Male Mice

Uncoupling protein 1 (UCP1) plays a central role in thermogenic tissues by uncoupling cellular respiration to dissipate energy. Beige adipocytes, an inducible form of thermogenic cells in subcutaneous adipose tissue (SAT), have become a major focus in obesity research. We have previously shown that eicosapentaenoic acid (EPA) ameliorated high-fat diet (HFD)-induced obesity by activating brown fat in C57BL/6J (B6) mice at thermoneutrality (30 °C), independently of UCP1. Here, we investigated whether ambient temperature (22 °C) impacts EPA effects on SAT browning in wild-type (WT) and UCP1 knockout (KO) male mice and dissected underlying mechanisms using a cell model. We observed resistance to diet-induced obesity in UCP1 KO mice fed HFD at ambient temperature, with significantly higher expression of UCP1-independent thermogenic markers, compared to WT mice. These markers included the fibroblast growth factor 21 (FGF21) and sarco/endoplasmic reticulum Ca²⁺-ATPase 2b (SERCA2b), suggesting the indispensable role of temperature in beige fat reprogramming. Surprisingly, although EPA induced thermogenic effects in SAT-derived adipocytes harvested from both KO and WT mice, EPA only increased thermogenic gene and protein expression in the SAT of UCP1 KO mice housed at ambient temperature. Collectively, our findings indicate that the thermogenic effects of EPA, which are independent of UCP1, occur in a temperature-dependent manner.

Role of adiponectin, resistin and monocyte chemo-attractant protein-1 in overweight/obese asthma phenotype in children

BACKGROUND

Asthma is a chronic inflammatory disorder of the airways with diverse overlapping pathologies and phenotypes contributing to a significant heterogeneity in clinical manifestations. Obesity may modify asthma risk, phenotype, and prognosis. A suggested mechanism linking obesity and asthma is through systemic inflammation. Adipokines secreted by adipose tissue were suggested to provide a link between obesity and asthma.

OBJECTIVE

To have an understanding for the contribution of adiponectin, resistin and MCP-1 to development of distinct asthma phenotype in overweight/obese children through assessment of their serum level and correlation to pulmonary function tests.

SUBJECTS AND METHODS

The study included 29 normal weight asthmatics, 23 overweight/obese asthmatic children and 30 controls. All cases were subjected to detailed history taking, thorough examination and pulmonary function tests. Serum adiponectin, resistin, MCP-1 and IgE were assessed to all recruited subjects.

RESULTS

Adiponectin level was significantly higher in overweight/obese asthmatics (24900 ± 1600 ng/ml) compared to normal weight asthmatics (21700 ± 1700 ng/ml) and control (23000 ± 3200 ng/ml), (p < 0.001 & 0.051 respectively). Normal weight asthmatics had significantly lower adiponectin level than control, (p = 0.039). A significant low level of MCP-1 in overweight/obese asthmatics (149.5 (20-545) ng/L) compared to control (175 (28 -1123.5) ng/L), p = 0.037. No significant difference was found regarding resistin. Normal weight asthmatics had significantly lower FEV₁% and FVC% compared to overweight/obese asthmatics (p = 0.036, 0.016 respectively). A significant positive correlation was found between (FEV1%, FVC) and BMI in normal weight asthmatics (P = 0.01, < 0.01 respectively) and a significant negative correlation between PEF and BMI (-0.42, p = 0.05) in obese/overweight asthmatics. Resistin/adiponectin ratio was not affected by sex, degree of asthma severity or level of asthma control in either normal weight or overweight/obese asthmatic.

CONCLUSION

This work could suggest that adiponectin may play a role in overweight/obese asthma phenotype where it is possible to have a dual action (pro & anti- inflammatory). It seems that resistin had no role in asthma pathogenesis.

Resistin Contribution to Cardiovascular Risk in Chronic Kidney Disease Male Patients

BACKGROUND

Resistin is a molecule that belongs to the Resistin-Like Molecules family (RELMs), the group of proteins taking part in inflammatory processes. Increased resistin concentrations are observed in cardiovascular complications. Resistin contributes to the onset of atherosclerosis and intensifies the atherosclerotic processes. The aim of this study was to investigate the relationship between resistin and cardiovascular (CV) risk in men with chronic kidney disease (CKD) not treated with dialysis.

MATERIALS AND METHODS

One hundred and forty-two men were included in the study: 99 men with eGFR lower than 60 mL/min/1.73 m² and 43 men with eGFR ≥ 60 mL/min/1.73 m². CV risk was assessed. Serum resistin, tumor necrosis factor-alpha (TNF-alpha) and plasminogen activator inhibitor-1 (PAI-1) were measured among other biochemical parameters.

RESULTS

We observed that resistin concentrations were significantly higher in patients with CKD compared to individuals with eGFR ≥ 60 mL/min/1.73 m² (p = 0.003). In CKD, after estimating the general linear model (GLM), we found that resistin is associated with CV risk (p = 0.026) and PAI-1 serum concentrations (0.012). The relationship of PAI-1 with resistin depends on the level of CV risk in CKD (p = 0.048).

CONCLUSIONS

Resistin concentrations rise with the increase of CV risk in CKD patients and thus resistin may contribute to the progression of cardiovascular risk in this group of patients. The relationship between resistin and CV risk is modified by PAI-1 concentrations.

Adipokines and incident venous thromboembolism: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Obesity leads to adipocyte hypertrophy and adipokine dysregulation and is an independent risk factor for venous thromboembolism (VTE). However, the association between adipokines and VTE is not well established.

OBJECTIVES

To examine whether adipokines are associated with increased risk of incident VTE.

METHODS

We studied 1888 participants of the Multi-Ethnic Study of Atherosclerosis cohort who were initially free of VTE and had adipokine (adiponectin, leptin, and resistin) levels measured at either examination 2 or 3 (2002-2004 or 2004-2005, respectively). During follow-ups, VTE was ascertained through hospitalization records and death certificates by using ICD-9 and 10 codes. We used multivariable Cox proportional hazards regression to assess the association between 1 standard deviation (SD) log-transformed increments in adipokines and incident VTE.

RESULTS

The mean ± SD age was 64.7 ± 9.6 years, and 49.8% of participants were women. Medians (interquartile range) of adiponectin, leptin, and resistin were 17.3 (11.8-26.2) mcg/mL, 13.5 (5.6-28.2) ng/mL, and 15.0 (11.9-19.0) ng/mL, respectively. There were 78 incident cases of VTE after a median of 9.7 (5.0-12.4) years of follow-up. After adjusting for sociodemographics, smoking, and physical activity, the hazard ratios (95% CIs) per 1 SD increment of adiponectin, leptin, and resistin were 1.14 (0.90-1.44), 1.29 (1.00-1.66), and 1.38 (1.09-1.74), respectively. The association for resistin persisted after further adjustments for body mass index and computed tomography-derived total visceral adipose tissue area.

CONCLUSION

Higher resistin levels were independently associated with greater risk of incident VTE. Larger prospective cohort studies are warranted to confirm this association.

Multiple sclerosis and obesity: The role of adipokines

Multiple Sclerosis (MS), a chronic inflammatory disease of the central nervous system that leads to demyelination and neurodegeneration has been associated with various environmental and lifestyle factors. Population-based studies have provided evidence showing the prevalence of MS is increasing worldwide. Because a similar trend has been observed for obesity and metabolic syndrome, interest has grown in possible underlying biological mechanisms shared by both conditions. Adipokines, a family of soluble factors produced by adipose tissue that participate in a wide range of biological functions, contribute to a low state of chronic inflammation observed in obesity, and influence immune function, metabolism, and nutritional state. In this review, we aim to describe epidemiological and biological factors common to MS and obesity, as well as provide an update on current knowledge of how different pro- and anti-inflammatory adipokines participate as immune response mediators in MS, as well as in the animal model for MS, namely, experimental autoimmune encephalomyelitis (EAE). Multiple Sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) leading to demyelination, and neurodegeneration. Although its pathogenesis is not yet fully understood, there is considerable evidence to suggest MS arises from complex interactions between individual genetic susceptibility and external environmental factors. In recent decades, population-based studies have provided evidence indicating the prevalence of MS is increasing worldwide, in parallel with the rise in obesity and metabolic syndrome. This synchronous increment in the incidence of both MS and obesity has led to a search for potential biological mechanisms linking both conditions. Notably, a large number of studies have established significant correlation between obesity and higher prevalence, or worse prognosis, of several immune-mediated conditions. Fat tissue has been found to produce a variety of soluble factors named adipokines. These mediators, secreted by both adipocytes as well as diverse immune cells, participate in a wide range of biological functions, further strengthening the concept of a link between immune function, metabolism, and nutritional state. Because obesity causes overproduction of pro-inflammatory adipokines (namely leptin, resistin and visfatin) and reduction of anti-inflammatory adipokines (adiponectin and apelin), adipose tissue dysregulation would appear to contribute to a state of chronic, low-grade inflammation favoring the development of disease. In this review, we present a summary of current knowledge related to the pathological effects of different adipokines, prevalent in obese MS patients.

Adiponectin Protects Hypoxia/Reoxygenation-Induced Cardiomyocyte Injury by Suppressing Autophagy

Adiponectin is a cytokine produced by adipocytes and acts as a potential cardioprotective agent and plays an important role in myocardial ischemia/reperfusion injury. In a myocardial hypoxia/reoxygenation model using neonatal rat ventricular myocytes, we investigated the contribution of adiponectin-mediated autophagy to its cardioprotective effects. Cardiomyocytes were exposed to hypoxia/reoxygenation pretreated with or without adiponectin in the presence of absence of rapamycin. Cell viability was analyzed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. Western blotting assay was used to determine the expression levels of microtubule-associated proteins 1A/1B light chain 3B (LC3B), adenosine monophosphate-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), p62/sequestosome 1, unc-51 like autophagy activating kinase 1 (ULK1), and Beclin-1. Autophagosome formation was detected by monodansylcadaverine staining. We found that hypoxia induced a time dependent decline in cardiomyocyte viability, and increase in autophagy and reoxygenation further augmented hypoxia-induced autophagy induction and consequently reduced cell viability. Adiponectin treatment alleviated hypoxia/reoxygenation-induced cellular damage and autophagy in cardiomyocytes. Adiponectin treatment also attenuated hypoxia/reoxygenation-promoted cardiomyocyte autophagy even in the presence of another autophagy stimulator rapamycin in part by inhibiting vacuolar hydron-adenosine triphosphatase. Additionally, autophagy suppression by adiponectin during hypoxia/reoxygenation was associated with the attenuated phosphorylation of AMPK and ULK1, augmented phosphorylation of mTOR, and the reduced protein expression levels of Beclin-1 in cardiomyocytes. Taken together, these results suggest that adiponectin protects ischemia/reperfusion-induced cardiomyocytes by suppressing autophagy in part through AMPK/mTOR/ULK1/Beclin-1 signaling pathway.

Cardiovascular protection by SGLT2 inhibitors - Do anti-inflammatory mechanisms play a role?

BACKGROUND

Metabolic syndrome and related metabolic disturbances represent a state of low-grade inflammation, which accelerates insulin resistance, type 2 diabetes (T2D) and cardiovascular disease (CVD) progression. Among antidiabetic medications, sodium glucose co-transporter (SGLT) 2 inhibitors are the only agents which showed remarkable reductions in heart failure (HF) hospitalizations and major cardiovascular endpoints (MACE) as well as renal endpoints regardless of diabetes status in large randomized clinical outcome trials (RCTs). Although the exact mechanisms underlying these benefits are yet to be established, growing evidence suggests that modulating inflammation by SGLT2 inhibitors may play a key role.

SCOPE OF REVIEW

In this manuscript, we summarize the current knowledge on anti-inflammatory effects of SGLT2 inhibitors as one of the mechanisms potentially mediating their cardiovascular (CV) benefits. We introduce the different metabolic and systemic actions mediated by these agents which could mitigate inflammation, and further present the signalling pathways potentially responsible for their proposed direct anti-inflammatory effects. We also discuss controversies surrounding some of these mechanisms.

MAJOR CONCLUSIONS

SGLT2 inhibitors are promising anti-inflammatory agents by acting either indirectly via improving metabolism and reducing stress conditions or via direct modulation of inflammatory signalling pathways. These effects were achieved, to a great extent, in a glucose-independent manner which established their clinical use in HF patients with and without diabetes.

Inflammation as a link between periodontal disease and obesity

Nutrition plays a critical role in the homeostatic balance, maintenance of health, and longevity. There is a close link between inflammatory diseases and nutritional health. Obesity is a severe pathological process with grave implications on several organ systems and disease processes, including type 2 diabetes, cardiovascular disease, osteoarthritis, and rheumatoid arthritis. The impact of obesity on periodontal inflammation has not been fully understood; the association between nutritional balance and periodontal inflammation is much less explored. This review is focused on the potential mechanistic links between periodontal diseases and obesity and common inflammatory activity pathways that can be pharmacologically targeted.

Obesity and Chronic Kidney Disease A Current Review

Background

Obesity poses significant challenges to healthcare globally, particularly through its bi-directional relationship with co-morbid metabolic conditions such as type 2 diabetes and hypertension. There is also emerging evidence of an association between obesity and chronic kidney disease (CKD) which is less well characterized.

Methods

A literature search of electronic libraries was conducted to identify and present a narrative review of the interplay between obesity and CKD.

Findings

Obesity may predispose to CKD directly as it is linked to the histopathological finding of obesity-related glomerulopathy and indirectly through its widely recognized complications such as atherosclerosis, hypertension, and type 2 diabetes. The biochemical and endocrine products of adipose tissue contribute to pathophysiological processes such as inflammation, oxidative stress, endothelial dysfunction, and proteinuria. The prevention and management of obesity may prove critical in counteracting both the development and advancement of CKD. Moreover, measures of abdominal adiposity such as waist circumference, are generally associated with worse morbidity and mortality in individuals receiving maintenance hemodialysis.

Conclusion

Obesity is a risk factor for the onset and progression of CKD and should be recognized as a potential target for a preventative public health approach to reduce CKD rates within the general population. Future research should focus on the use of glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors in patients with CKD and obesity due to their multi-faceted actions on major outcomes.

The Role of Perivascular Adipose Tissue-Derived Hydrogen Sulfide in the Control of Vascular Homeostasis

Significance: Emerging evidence suggests that perivascular adipose tissue (PVAT) has a relevant role in the control of vascular tone in physiology and pathology. Healthy PVAT has anticontractile, anti-inflammatory, and antioxidative actions. Accumulating data from both human and experimental animal models indicate that PVAT dysfunction is conceivably coupled to cardiovascular diseases, and it is associated with vascular inflammation, oxidative stress, and arterial remodeling. Therefore, "healthy" PVAT may constitute a novel therapeutic target for the prevention and treatment of cardiovascular diseases. Recent Advances: Hydrogen sulfide (H₂S) has been recognized as a vascular anti-contractile factor released from PVAT. The enzymes deputed to H₂S biosynthesis are variously expressed in PVAT and strictly dependent on the vascular bed and species. Metabolic and cardiovascular diseases can alter the morphological and secretory characteristics of PVAT, influencing also the H₂S signaling. Here, we discuss the role of PVAT-derived H₂S in healthy conditions and its relevance in alterations occurring in vascular disorders. Critical Issues: We discuss how a better understanding may help in the prevention of vascular dysfunction related to alteration in PVAT-released H₂S as well as the importance of the interplay between PVAT and H₂S. Future Directions: We propose future directions to evaluate the contribution of each enzyme involved in H₂S biosynthesis and their alteration/switch occurring in vascular disorders and the remaining challenges in investigating the role of H₂S. Antioxid. Redox Signal. 37, 84-97.

Resistin Associated With Cytokines and Endothelial Cell Adhesion Molecules Is Related to Worse Outcome in COVID-19

Introduction

Resistin is reported to form a cytokine network and cause endothelial damage. The pathogenesis of coronavirus disease 2019 (COVID-19) remains unknown, but the association between cytokine storm and endothelial damage is crucial. This study aimed to evaluate resistin in COVID-19 pathogenesis compared with sepsis.

Materials and Methods

First, we evaluated the association of plasma resistin levels and disease severity and clinical outcome in two large cohorts: a publicly available cohort including 306 COVID-19 patients in the United States (MGH cohort) and our original cohort including only intubated 113 patients in Japan (Osaka cohort 1). Second, to understand pathogenesis, we evaluate resistin, cytokines and endothelial cell adhesion molecules in COVID-19 compared with sepsis. Blood samples were collected from 62 ICU-treated COVID-19 patients and 38 sepsis patients on day 1 (day of ICU admission), days 2-3, days 6-8, and from 18 healthy controls (Osaka cohort 2). The plasma resistin, inflammatory cytokines (IL-6, IL-8, MCP-1 and IL-10) and endothelial cell adhesion molecules (ICAM-1 and VCAM-1) were compared between patients and control. Correlations among resistin, inflammatory cytokines and endothelial cell adhesion molecules were evaluated in COVID-19 and sepsis.

Results

In the MGH cohort, the day 1 resistin levels were associated with disease severity score. The non-survivors showed significantly greater resistin levels than survivors on days 1, 4 and 8. In the Osaka cohort 1, 28-day non-survivors showed significantly higher resistin levels than 28-day survivors on days 6-8. Patients with late recovery (defined as the day of weaning off mechanical ventilation >12 or death) had significantly higher resistin levels than those with early recovery on day 1 and days 6-8. In the Osaka cohort 2, plasma resistin levels were elevated in COVID-19 and sepsis patients compared to controls at all measurement points and were associated with inflammatory cytokines and endothelial cell adhesion molecules.

Conclusion

Resistin was elevated in COVID-19 patients and was associated with cytokines and endothelial cell adhesion molecules. Higher resistin levels were related to worse outcome.

Distribution of Adiponectin Receptors in the Brain of Adult Mouse: Effect of a Single Dose of the Adiponectin Receptor Agonist, AdipoRON, on Ischemic Stroke

Adiponectin exhibits pleiotropic effects, including anti-inflammatory, anti-apoptotic, anti-oxidant, and neuroprotective ones. Although some studies have documented brain expression in different rodent models of its receptors, AdipoR1 and AdipoR2, their global distribution remains incomplete. Here, we demonstrated that both AdipoR are widely distributed in the brains of adult mice. Furthermore, by double immunostaining studies, we showed that AdipoR1 and AdipoR2 are mainly expressed in neurons and blood vessels. Then, considering the wide distribution of both receptors and the neuroprotective effects of adiponectin, we tested the therapeutic effect of a single injection of the adiponectin receptor agonist, AdipoRON (5 mg.kg⁻¹), 24 h after stroke in a model of middle cerebral artery occlusion technique (MCAO). Under our experimental conditions, we demonstrated that AdipoRON did not modulate the infarct volume, cell death, neuroinflammatory parameters including microglia activation and oxidative stress. This study suggests that a protocol based on multiple injections of AdipoRON at a higher dose after MCAO could be considered to promote the therapeutic properties of AdipoRON on the brain repair mechanism and recovery.

The spike protein of SARS-CoV-2 induces endothelial inflammation through integrin α5β1 and NF-κB signaling

Vascular endothelial cells (ECs) form a critical interface between blood and tissues that maintains whole-body homeostasis. In COVID-19, disruption of the EC barrier results in edema, vascular inflammation, and coagulation, hallmarks of this severe disease. However, the mechanisms by which ECs are dysregulated in COVID-19 are unclear. Here, we show that the spike protein of SARS-CoV-2 alone activates the EC inflammatory phenotype in a manner dependent on integrin ⍺5β1 signaling. Incubation of human umbilical vein ECs with whole spike protein, its receptor-binding domain, or the integrin-binding tripeptide RGD induced the nuclear translocation of NF-κB and subsequent expression of leukocyte adhesion molecules (VCAM1 and ICAM1), coagulation factors (TF and FVIII), proinflammatory cytokines (TNF⍺, IL-1β, and IL-6), and ACE2, as well as the adhesion of peripheral blood leukocytes and hyperpermeability of the EC monolayer. In addition, inhibitors of integrin ⍺5β1 activation prevented these effects. Furthermore, these vascular effects occur in vivo, as revealed by the intravenous administration of spike, which increased expression of ICAM1, VCAM1, CD45, TNFα, IL-1β, and IL-6 in the lung, liver, kidney, and eye, and the intravitreal injection of spike, which disrupted the barrier function of retinal capillaries. We suggest that the spike protein, through its RGD motif in the receptor-binding domain, binds to integrin ⍺5β1 in ECs to activate the NF-κB target gene expression programs responsible for vascular leakage and leukocyte adhesion. These findings uncover a new direct action of SARS-CoV-2 on EC dysfunction and introduce integrin ⍺5β1 as a promising target for treating vascular inflammation in COVID-19.

Environmental Contaminants Acting as Endocrine Disruptors Modulate Atherogenic Processes: New Risk Factors for Cardiovascular Diseases in Women?

The number of aged individuals is increasing worldwide, rendering essential the comprehension of pathophysiological mechanisms of age-related alterations, which could facilitate the development of interventions contributing to “successful aging” and improving quality of life. Cardiovascular diseases (CVD) include pathologies affecting the heart or blood vessels, such as hypertension, peripheral artery disease and coronary heart disease. Indeed, age-associated modifications in body composition, hormonal, nutritional and metabolic factors, as well as a decline in physical activity are all involved in the increased risk of developing atherogenic alterations that raise the risk of CVD development. Several factors have been reported to play a role in the alterations observed in muscle and endothelial cells and that lead to increased CVD, such as genetic pattern, smoking and unhealthy lifestyle. Moreover, a difference in the risk of these diseases in women and men has been reported. Interestingly, in the past decades attention has been focused on a potential role of several pollutants that disrupt human health by interfering with hormonal pathways, and more specifically in non-communicable diseases such as obesity, diabetes and CVD. This review will focus on the potential alteration induced by Endocrine Disruptors (Eds) in the attempt to characterize a potential role in the cellular and molecular mechanisms involved in the atheromatous degeneration process and CVD progression.

Associations of adipokine levels with the prevalence and extent of valvular and thoracic aortic calcification: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

Extra-coronary calcification (ECC) is a marker of atherosclerosis and independently associated with cardiovascular disease (CVD). Adipokines may mediate the effect of obesity on atherosclerosis. However, the relationship of adipokines with ECC is not well-established. We examined the associations of leptin, resistin and adiponectin with ECC in a diverse community-based cohort.

METHODS

We performed a cross-sectional analysis of 1897 adults without clinical CVD in the MESA cohort. Serum adipokine levels and non-contrast cardiac CT scans were obtained at Exam 2 or 3 (randomly assigned). ECC was quantified by Agatston score and included calcification of the mitral annulus (MAC), aortic valve (AVC), ascending thoracic aorta (ATAC) and descending thoracic aorta (DTAC). We used multivariable regression to evaluate the associations between leptin, resistin and adiponectin [per 1 SD ln(adipokine] with ECC prevalence (score >0) and extent [ln(score+1)].

RESULTS

The mean age of participants was 65 ± 10 years; 49% women. After adjusting for demographic factors, adiponectin was inversely associated with AVC prevalence and extent; leptin positively associated with MAC prevalence and extent; and resistin positively associated with ATAC prevalence and extent and DTAC extent. After adjustment for BMI and other CVD risk factors, adiponectin remained inversely associated with AVC prevalence, and resistin remained associated with greater ATAC prevalence and extent. Leptin was not associated with measures of ECC after full adjustment. No adipokine was associated with MAC after full adjustment.

CONCLUSIONS

We identified significant associations between select adipokines and specific markers of ECC. Adipokines may play a role in the development of systemic atherosclerosis.

High Serum Levels of Resistin is Associated With Acute Cerebral Infarction

BACKGROUND

The inflammatory process is involved in the pathogenesis of atherosclerosis and brain tissue injury following cerebral ischemia. Human resistin is a member of small cysteine-rich secreted proteins and has been implicated in inflammatory responses. This study investigated the association of serum resistin level with acute cerebral infarction (ACI). We also investigated its association with the short-term functional outcome.

METHODS

This study included 106 patients with ACI and 106 age-matched and sex-matched healthy control subjects. Serum resistin level was assessed by using enzyme-linked immunosorbent sandwich assay. The association of serum resistin levels with ACI was analyzed by logistic regression analysis.

RESULTS

The serum resistin level was significantly higher in patients with ACI than the control group [median (interquartile range), 35.7 ng/mL (13.0 to 70.5) ng/mL vs. 10.5 ng/ml (15.4 to 16.6), P<0.001]. Logistic regression analysis showed that serum resistin level was associated with an ACI (odds ratio=1.055, 95% confidence interval: 1.035-1.074, P<0.001). Among stroke subtypes, the serum resistin level was higher in the patients with large artery atherosclerosis than those with other subtypes (P=0.013). High resistin levels were also significantly associated with unfavorable functional outcome at discharge (odds ratio=1.043, 95% confidence interval: 1.024-1.063, P<0.001).

CONCLUSIONS

This study suggests the potential association of resistin with stroke and cerebral atherosclerosis. Increased serum resistin levels were also associated with early unfavorable neurological outcome.

Adipokines in dental pulp: physiological, pathological, and potential therapeutic roles

BACKGROUND

Hundreds of adipokines have been identified, and their extensive range of endocrine functions-regulating distant organs such as oral tissues-and local autocrine/paracrine roles have been studied. In dentistry, however, adipokines are poorly known proteins in the dental pulp; few of them have been studied despite their large number. This study reviews recent advances in the investigation of dental-pulp adipokines, with an emphasis on their roles in inflammatory processes and their potential therapeutic applications.

HIGHLIGHTS

The most recently identified adipokines in dental pulp include leptin, adiponectin, resistin, ghrelin, oncostatin, chemerin, and visfatin. They have numerous physiological and pathological functions in the pulp tissue: they are closely related to pulp inflammatory mechanisms and actively participate in cell differentiation, mineralization, angiogenesis, and immune-system modulation.

CONCLUSION

Adipokines have potential clinical applications in regenerative endodontics and as biomarkers or targets for the pharmacological management of inflammatory and degenerative processes in dental pulp. A promising direction for the development of new therapies may be the use of agonists/antagonists to modulate the expression of the most studied adipokines.

Adipokines as Immune Cell Modulators in Multiple Sclerosis

Multiple sclerosis (MS), a chronic inflammatory and demyelinating disease of the central nervous system (CNS), is a major clinical and societal problem, which has a tremendous impact on the life of patients and their proxies. Current immunomodulatory and anti-inflammatory therapies prove to be relatively effective; however, they fail to concomitantly stop ongoing neurological deterioration and do not reverse acquired disability. The proportion to which genetic and environmental factors contribute to the etiology of MS is still incompletely understood; however, a recent association between MS etiology and obesity was shown, with obesity greatly increasing the risk of developing MS. An altered balance of adipokines, which are white adipose tissue (WAT) hormones, plays an important role in the low-grade chronic inflammation during obesity by their pervasive modification of local and systemic inflammation. Vice versa, inflammatory factors secreted by immune cells affect adipokine function. To explore the role of adipokines in MS pathology, we will here review the reciprocal effects of adipokines and immune cells and summarize alterations in adipokine levels in MS patient cohorts. Finally, we will discuss proof-of-concept studies demonstrating the therapeutic potential of adipokines to target both neuroinflammation and neurodegeneration processes in MS.

Salmon peptides limit obesity-associated metabolic disorders by modulating a gut-liver axis in vitamin D-deficient mice

OBJECTIVE

This study investigated the effects of a low-dose salmon peptide fraction (SPF) and vitamin D₃ (VitD₃ ) in obese and VitD₃ -deficient mice at risk of metabolic syndrome (MetS).

METHODS

Obese and VitD₃ -deficient low-density lipoprotein receptor (LDLr)^-/- /apolipoprotein B100 (ApoB)^100/100 mice were treated with high-fat high-sucrose diets, with 25% of dietary proteins replaced by SPF or a nonfish protein mix (MP). The SPF and MP groups received a VitD₃ -deficient diet or a supplementation of 15,000 IU of VitD₃ per kilogram of diet. Glucose homeostasis, atherosclerosis, nonalcoholic fatty liver disease, and gut health were assessed.

RESULTS

VitD₃ supplementation increased plasma 25-hydroxyvitamin D to optimal status whereas the VitD₃ -deficient diet maintained moderate deficiency. SPF-treated groups spent more energy and accumulated less visceral fat in association with an improved adipokine profile. SPF lowered homeostatic model assessment of insulin resistance compared with MP, suggesting that SPF can improve insulin sensitivity. SPF alone blunted hepatic and colonic inflammation, whereas VitD₃ supplementation attenuated ileal inflammation. These effects were associated with changes in gut microbiota such as increased Mogibacterium and Muribaculaceae.

CONCLUSIONS

SPF treatment improves MetS by modulating hepatic and gut inflammation along with gut microbiota, suggesting that SPF operates through a gut-liver axis. VitD₃ supplementation has limited influence on MetS in this model.

Study of Some Inflammatory Mediators in the Serum of Patients With Atherosclerosis and Acute Myocardial Infarction

Background and aim of the study The aim of this study is to evaluate the changes in the inflammatory mediator's serum amyloid A (SAA), adiponectin, and resistin in the serum of patients with stable angina and acute myocardial infarction. Subjects and methods The study was done on 60 subjects divided into three groups: 20 healthy normal individuals as a control group, 20 patients with stable angina (atherosclerotic plaque), and 20 patients with myocardial infarction. Fasting blood samples were withdrawn from all subjects and serum was prepared. SAA, resistin, and adiponectin levels were quantitatively measured by enzyme-linked immunosorbent assay (ELISA). Results The SAA level was significantly higher in both stable angina and the acute myocardial infarction group than the control group (2.7179 ± 0.44501 mg/L) and the serum resistin level was significantly higher (p-value = 0.0) in the stable angina (8.368 ± 1.633 ng/ml) and the acute myocardial infarction (13.606 ± 2.067 ng/ml) groups (p-value= 0.0) than the control group. (2.4272±1.25210 ng/ml). Moreover, resistin levels in stable angina when compared to the AMI showed a significant difference between them (p-value = 0.0) while adiponectin was significantly lower in the acute myocardial infarction group. (6.641±2.6011 µg/mL, p-value = 0.019) than its level in the control group (11.873±1.798 µg/mL). While the adiponectin level showed no significant differences between stable angina in comparison to the AMI. Conclusion SAA can be used as a confirmatory marker for stable angina and a diagnostic tool for AMI patients. Both SAA and resistin may participate in the atherosclerosis process as an effectors molecule of inflammatory reactions. For adiponectin, we concluded that it has the antiatherogenic property and its levels were lower in both the stable angina and acute myocardial infarction groups.

Metabolic syndrome and hidradenitis suppurativa: epidemiological, molecular, and therapeutic aspects

Hidradenitis suppurativa (HS) is a chronic, suppurative condition of the pilosebaceous unit. Patients suffering from HS demonstrate a molecular profile in keeping with a state of systemic inflammation and are often found to fit the criteria for a diagnosis of metabolic syndrome (MetS). In this paper, we review the literature with regards to established data on the prevalence of MetS in HS patients and revise the odds ratio of comorbid disease. Furthermore, we attempt to draw parallels between inflammatory pathways in HS and MetS and evaluate how convergences may explain the risk of comorbid disease, necessitating the need for multidisciplinary care.

Adiponectin and cardiometabolic trait and mortality: where do we go?

Adiponectin is an adipocyte-derived cytokine known for its cardioprotective effects in preclinical studies. Early epidemiologic studies replicated these findings and drew great interest. Subsequent large-scale prospective cohorts, however, showed that adiponectin levels seemed not to relate to incident coronary artery disease (CAD). Even more surprisingly, a paradoxical increase of all-cause and cardiovascular (CV) mortality with increased adiponectin levels was reported. The adiponectin-mortality paradox has been explained by some groups asserting that adiponectin secretion is promoted by elevated natriuretic peptides (NP). Other groups have proposed that adiponectin is elevated due to adiponectin resistance in subjects with metabolic syndrome or heart failure (HF). However, there is no unifying theory that can clearly explain this paradox. In patients with HF with reduced ejection fraction (HFrEF), stretched cardiomyocytes secrete NPs, which further promote release of adiponectin from adipose tissue, leading to adiponectin resistance. On the other hand, adiponectin biology may differ in patients with heart failure with preserved ejection fraction (HFpEF), which constitutes 50% of all of HF. Most HFpEF patients are obese, which exerts inflammation and myocardial stiffness, that is likely to prevent myocardial stretch and subsequent NP release. This segment of the patient population may display a different adiponectin biology from its HFrEF counterpart. Dissecting the adiponectin-mortality relation in terms of different HF subtypes may help to comprehensively understand this paradox. Mendelian Randomization (MR) analyses claimed that adiponectin levels are not causally related to CAD or metabolic syndrome. Results from MR studies, however, should be interpreted with great caution because the underlying history of CAD or CHF were not taken into account in these analyses, an issue that may substantially confound the results. Here, we discuss many aspects of adiponectin; cardiometabolic traits, therapeutic interventions, and the ongoing debate about the adiponectin paradox, which were recently described in basic, epidemiologic, and clinical studies.

Ghrelin and adipokines: An overview of their physiological role, antimicrobial activity and impact on cardiovascular conditions

The human body has many different hormones that interact with each other and with other factors such as proteins, cell receptors and metabolites. There is still a limited understanding of some of the underlying biological mechanisms of some hormones. In the past decades, science and technology have made major advancements in regard to innovation and knowledge in fields such as medicine. However, some conditions are complex and have many variables that their full picture is still unclear, even though some of these conditions have an alarming rate of incidence and serious health consequences. Conditions such as type 2 diabetes, obesity, nonalcoholic liver disease (NAFLD), cancer in its different forms and even mental conditions, such as Alzheimer's disease, are some of the most common diseases in the 21st century. These conditions are relevant not only because of their high incidence on the general population, but also because of their severity. In this chapter, we present an overview of cardiovascular (CV) diseases. According to the World Health Organization (WHO), cardiovascular diseases, such as coronary artery disease (CAD), heart attack, cardiomyopathy and heart failure (among others), are the number one cause of death worldwide. In 2016, it was estimated that 17.9 million people died from CV diseases, representing more than 30% of all global deaths. Approximately 95% of people who died from CV diseases were so-called "premature deaths" because were referenced to individuals under the age of 70 years old. In this chapter we described some of the hormones that may have an impact on CV diseases, including ghrelin, a peptide that is mostly produced in the stomach, known to induce hunger. Ghrelin is linked to an increase in body fat, i.e., adipose tissue in animals. For this reason, we also included the adipokines leptin, adiponectin and resistin. The main objectives of this chapter are to present the state of the art knowledge concerning the mechanisms of each hormone relevant to CV diseases; to compile data and results that further elucidate the relevance of these peptides for several physiological events, conditions and diseases; and to discuss the metabolic impact of each hormone. We established connections between multiple peptides and the underlying condition/disease with tools such as STRING, referring to research using databases, such as UniProt, DisGeNET and Proteomics DB. Fig. 1 shows a network that summarizes the information presented in this chapter, which serves as a visual representation.

Adipokines in vascular calcification

Adipose tissue (AT), a critical endocrine gland, is capable of producing and secreting abundant adipokines. Adipokines act on distant or adjacent organ tissues via paracrine, autocrine, and endocrine mechanism, which play attractive roles in the regulation of glycolipid metabolism and inflammatory response. Increasing evidence shows that adipokines can connect obesity with cardiovascular diseases by serving as promoters or inhibitors in vascular calcification. The chronic hypoxia in AT, caused by the adipocyte hypertrophy, is able to trigger imbalanced adipokine generation, which leads to apoptosis, osteogenic differentiation of vascular smooth muscle cells (VSMCs), vascular inflammation, and abnormal deposition of calcium and phosphorus in the vessel wall. The objectives of this review aim at providing a brief summary of the crucial influence of major adipokines on the formation and development of vascular calcification, which may contribute to better understanding these adipokines for establishing the appropriate therapeutic strategies to counteract obesity-associated vascular calcification.

Cellular and Molecular Processes in Pulmonary Hypertension

Pulmonary hypertension (PH) is a progressive lung disease characterized by persistent pulmonary vasoconstriction. Another well-recognized characteristic of PH is the muscularization of peripheral pulmonary arteries. This pulmonary vasoremodeling manifests in medial hypertrophy/hyperplasia of smooth muscle cells (SMCs) with possible neointimal formation. The underlying molecular processes for these two major vascular responses remain not fully understood. On the other hand, a series of very recent studies have shown that the increased reactive oxygen species (ROS) seems to be an important player in mediating pulmonary vasoconstriction and vasoremodeling, thereby leading to PH. Mitochondria are a primary site for ROS production in pulmonary artery (PA) SMCs, which subsequently activate NADPH oxidase to induce further ROS generation, i.e., ROS-induced ROS generation. ROS control the activity of multiple ion channels to induce intracellular Ca²⁺ release and extracellular Ca²⁺ influx (ROS-induced Ca²⁺ release and influx) to cause PH. ROS and Ca²⁺ signaling may synergistically trigger an inflammatory cascade to implicate in PH. Accordingly, this paper explores the important roles of ROS, Ca²⁺, and inflammatory signaling in the development of PH, including their reciprocal interactions, key molecules, and possible therapeutic targets.

PVAT targets VSMCs to regulate vascular remodelling: angel or demon

Vascular remodelling refers to abnormal changes in the structure and function of blood vessel walls caused by injury, and is the main pathological basis of cardiovascular diseases such as atherosclerosis, hypertension, and pulmonary hypertension. Among them, the neointimal hyperplasia caused by abnormal proliferation of vascular smooth muscle cells (VSMCs) plays a key role in the pathogenesis of vascular remodelling. Perivascular adipose tissue (PVAT) can release vasoactive substances to target VSMCs and regulate the pathological process of vascular remodelling. Specifically, PVAT can promote the conversion of VSMCs phenotype from contraction to synthesis by secreting visfatin, leptin, and resistin, and participate in the development of vascular remodelling-related diseases. Conversely, it can also inhibit the growth of VSMCs by secreting adiponectin and omentin to prevent neointimal hyperplasia and alleviate vascular remodelling. Therefore, exploring and developing new drugs or other treatments that facilitate the beneficial effects of PVAT on VSMCs is a potential strategy for prevention or treatment of vascular remodelling-related cardiovascular diseases.

Resistance training decreases plasma levels of adipokines in postmenopausal women

Physical inactivity and the onset of menopause increase the risk of cardiovascular disease amongst postmenopausal women. We aim to investigate the effect of resistance training (RT) on plasma levels of selected cytokines, adipokines, myokines, and sex hormones in postmenopausal women with vasomotor symptoms. This was a sub-study of a randomised controlled trial investigating the effects of RT on vasomotor symptoms in postmenopausal women. Women were randomised to join a 15-week RT program (n = 26) or remain sedentary as control (n = 29). Venous blood samples were taken at week-0 and week-15 for all participants. Enzyme-linked immunosorbent assays and multiple bead assays were used to measure cytokines, adipokines, myokines, and sex hormones in plasma. Plasma measurements of 16 of 33 analytes were within detectable limits. After adjusting for good compliance in the RT group (58% of RT participants), after 15 weeks, significantly lower plasma levels of adiponectin (p < 0.001), lipocalin-2 (p < 0.01) and resistin (p = 0.04) were found. Comparing control and RT women, using change-over-time values, significant increases in median testosterone and sex hormone binding globulin levels were seen in RT women. RT intervention lowers the levels of adipokines, particularly adiponectin, in postmenopausal women with vasomotor symptoms. These results were secondary outcomes of a clinical trial, and further investigations in a larger cohort are essential with the additional control of diet control and body composition analyses. Nevertheless, our study shows RT may be a beneficial intervention in reducing inflammation amongst postmenopausal women.

Potential Benefits of Acupuncture and Herbs for Obesity-Related Chronic Inflammation by Adipokines

The adipose tissue is an organ that stores energy in the form of fats. It also has been known as an endocrine playing an integral role in metabolic homeostasis by secreting various adipokines. In obesity, the adipokine components and secretion patterns are altered toward proinflammation with weight gain, causing low chronic inflammation, which is closely linked to various metabolic diseases. Acupuncture and herbs are used for the management of obesity and its comorbidities, and it has been observed that these therapies affect the amount of expression and concentration of adipokines with improved metabolic phenotypes in both animal and human metabolic diseases. In this review, we discuss the role of adipokines and summarize beneficial effects of the treatments such as electroacupuncture, pharmacopuncture, catgut embedding acupuncture, and single and multiple medicinal herbs on obesity and its relations to adipokine composition. It will provide a new insight for applying adipokines as surrogate markers in complementary and alternative medicine practice.

Recent insights on modulation of inflammasomes by adipokines: a critical event for the pathogenesis of obesity and metabolism-associated diseases

Aberrant production of adipokines, a group of adipocytes-derived hormones, is considered one of the most important pathological characteristics of obesity. In individuals with obesity, beneficial adipokines, such as adiponectin are downregulated, whereas leptin and other pro-inflammatory adipokines are highly upregulated. Hence, the imbalance in levels of these adipokines is thought to promote the development of obesity-linked complications. However, the mechanisms by which adipokines contribute to the pathogenesis of various diseases have not been clearly understood. Inflammasomes represent key signaling platform that triggers the inflammatory and immune responses through the processing of the interleukin family of pro-inflammatory cytokines in a caspase-1-dependent manner. Beyond their traditional function as a component of the innate immune system, inflammasomes have been recently integrated into the pathological process of multiple metabolism- and obesity-related disorders such as cardiovascular diseases, diabetes, fatty liver disease, and cancer. Interestingly, emerging evidence also highlights the role of adipokines in the modulation of inflammasomes activation, making it a promising mechanism underlying distinct biological actions of adipokines in diseases driven by inflammation and metabolic disorders. In this review, we summarize the effects of adipokines, in particular adiponectin, leptin, visfatin and apelin, on inflammasomes activation and their implications in the pathophysiology of obesity-linked complications.

Adipokines and Inflammation: Focus on Cardiovascular Diseases

It is well established that adipose tissue, apart from its energy storage function, acts as an endocrine organ that produces and secretes a number of bioactive substances, including hormones commonly known as adipokines. Obesity is a major risk factor for the development of cardiovascular diseases, mainly due to a low grade of inflammation and the excessive fat accumulation produced in this state. The adipose tissue dysfunction in obesity leads to an aberrant release of adipokines, some of them with direct cardiovascular and inflammatory regulatory functions. Inflammation is a common link between obesity and cardiovascular diseases, so this review will summarise the role of the main adipokines implicated in the regulation of the inflammatory processes occurring under the scenario of cardiovascular diseases.

Perivascular Adipose Tissue as a Target for Antioxidant Therapy for Cardiovascular Complications

Perivascular adipose tissue (PVAT) is the connective tissue surrounding most of the systemic blood vessels. PVAT is now recognized as an important endocrine tissue that maintains vascular homeostasis. Healthy PVAT has anticontractile, anti-inflammatory, and antioxidative roles. Vascular oxidative stress is an important pathophysiological event in cardiometabolic complications of obesity, type 2 diabetes, and hypertension. Accumulating data from both humans and experimental animal models suggests that PVAT dysfunction is potentially linked to cardiovascular diseases, and associated with augmented vascular inflammation, oxidative stress, and arterial remodeling. Reactive oxygen species produced from PVAT can be originated from mitochondria, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, and uncoupled endothelial nitric oxide synthase. PVAT can also sense vascular paracrine signals and response by secreting vasoactive adipokines. Therefore, PVAT may constitute a novel therapeutic target for the prevention and treatment of cardiovascular diseases. In this review, we summarize recent findings on PVAT functions, ROS production, and oxidative stress in different pathophysiological settings and discuss the potential antioxidant therapies for cardiovascular diseases by targeting PVAT.

The Role of Adipokines in the Development of Arterial Stiffness and Hypertension

The study aimed to assess the role and the relationship of adipokines as well as parameters of arterial stiffness in newly diagnosed hypertension. Forty-nine newly diagnosed hypertensive cases (median age 47 ± 6 years) and 48 normotensive patients (median age 47 ± 6 years) were enrolled to this study. Patients underwent echocardiography, noninvasive assessment of hemodynamic parameters using SphygmoCor tonometer (Atcor Med). The levels of the adipokines-leptin, adiponectin, and resistin-were investigated. The augmentation pressure, augmentation index, and pulse wave velocity (PWV) were higher in patients with hypertension compared with controls (Ps < .05). Patients with hypertension had higher E/E' ratio, higher diameter of left atrium, and lower tricuspid annular plane systolic excursion compared with the control group (Ps < .05). Patients with hypertension had significant higher levels of leptin (ng/mL) and lower levels of adiponectin (μg/mL) compared with normotensive patients. The multivariate analysis showed that PWV (odds ratio [OR] 1.95, 95% CI, 1.2-2.9; P = .002) and leptin level (OR 1.01, 95% CI, 1.004-1.031; P = .01) were significantly associated with hypertension. Arterial stiffness as determined by PWV and leptin are associated with newly diagnosed hypertension. Elevated serum leptin level may influence the potential mechanism leading to sympathetic activation.

Mechanistic Links Between Obesity, Diabetes, and Blood Pressure: Role of Perivascular Adipose Tissue

Obesity is increasingly prevalent and is associated with substantial cardiovascular risk. Adipose tissue distribution and morphology play a key role in determining the degree of adverse effects, and a key factor in the disease process appears to be the inflammatory cell population in adipose tissue. Healthy adipose tissue secretes a number of vasoactive adipokines and anti-inflammatory cytokines, and changes to this secretory profile will contribute to pathogenesis in obesity. In this review, we discuss the links between adipokine dysregulation and the development of hypertension and diabetes and explore the potential for manipulating adipose tissue morphology and its immune cell population to improve cardiovascular health in obesity.

Perivascular Adipocytes in Vascular Disease

Perivascular adipocytes residing in the vascular adventitia are recognized as distinct endocrine cells capable of responding to inflammatory stimuli and communicating with the sympathetic nervous system and adjacent blood vessel cells, thereby releasing adipocytokines and other signaling mediators to maintain vascular homeostasis. Perivascular adipocytes exhibit phenotypic heterogeneity (both white and brown adipocytes) and become dysfunctional in conditions, such as diet-induced obesity, thus promoting vascular inflammation, vasoconstriction, and smooth muscle cell proliferation to potentially contribute to the development of vascular diseases, such as atherosclerosis, hypertension, and aortic aneurysms. Although accumulating data have advanced our understanding of the role of perivascular adipocytes in modulating vascular function, their impact on vascular disease, particularly in humans, remains to be fully defined. This brief review will discuss the mechanisms whereby perivascular adipocytes regulate vascular disease, with a particular emphasis on recent findings and current limitations in the field of research.

Leptin: Adiponectin ratio discriminated the risk of metabolic syndrome better than adiponectin and leptin in Southwest Nigeria

AIM

To assess the ability of leptin, adiponectin and leptin: adiponectin ratio (LAR) to discriminate apparently healthy subjects with metabolic syndrome in Southwest Nigeria.

METHODS

One hundred and twenty three subjects with metabolic syndrome (cases) were age matched with 123 subjects without metabolic syndrome. The serum adiponectin and leptin levels were measured using standard procedures. The ability of serum adiponectin, leptin and LAR to discriminate metabolic syndrome and its components were determined using the receiver operating curve and linear regression.

RESULTS

The median age of the cases (49 IQR 42, 56 years) was not significantly different from the controls (48 IQR 39, 56 years) p = 0.252. The adiponectin levels was reduced with increasing number of the components of metabolic syndrome from 11.6 (IQR 9.6, 13.5) among subjects without any component of metabolic syndrome to 6.5 (IQR 5.7, 7.7) in subjects with more than three components of metabolic syndrome. For leptin and LAR, the values increased with increasing components (p < 0.001). LAR (AUC 0.960) discriminated metabolic syndrome better than adiponectin (AUC 0.865) and leptin (AUC = 0.918) in males and females (LAR AUC = 0.966, adiponectin AUC = 0.888, leptin AUC = 0.929).

CONCLUSION

LAR had better ability to discriminate the risk of metabolic syndrome than adiponectin and leptin alone in males and females among apparently healthy subjects from Southwest Nigeria.