Adiponectin in relation to exercise and physical performance in patients with type 2 diabetes and coronary artery disease

Adiponectin deficiency prevents chronic colitis-associated colonic fibrosis via inhibiting CXCL13 production

INTRODUCTION

Colonic fibrosis is a long-term complication of inflammatory bowel disease (IBD), often leading to functional impairment, intestinal obstruction, and surgery. Adiponectin (APN) is an adipokine derived from adipocytes that plays a pleiotropic role in fibrosis regulation, depending on tissue and cell type specific or disease context, but its role in colonic fibrosis remains unclear.

OBJECTIVE

To explore the role and involved mechanism of APN in chronic colitis-associated colonic fibrosis.

METHODS

Studies were performed in GEO database, colonic tissues of UC patients, dextran sulfate sodium (DSS)-induced colonic fibrosis in male wild-type (WT) and APN-/- mice, mouse L929 and human CCD-18Co fibroblasts treated with recombinant CXCL13 protein, and colonic fibrosis in WT mice infected with shRNA of CXCL13.

RESULTS

APN was highly expressed in the colonic tissues of UC patients and positively correlated with the colonoscopy score and colonic fibrosis markers COL1A1 and COL3A1. APN deficiency significantly improved chronic colitis-induced colonic fibrosis in mice with down-regulating collagenase accumulation and expressions of TGF-β, α-SMA, COL1A1, COL3A1, and MMP-9 in colonic tissues. Transcriptomics showed that APN deficiency mainly affected cytokine-cytokine receptor interactions, especially CXCL13 signaling. Follow-up studies showed that APN deficiency significantly decreased the number of colonic F4/80+CD206+CXCL13+ macrophages by weakening Akt phosphorylation. Additional experiments confirmed that CXCL13 notably increased the expressions of α-SMA and COL1A1 in mouse and human fibroblasts by activating p-Akt, p-p38, p-ERK, and p-JNK. Moreover, inhibiting CXCL13 with shRNA significantly ameliorated colonic fibrosis in mice with DSS-induced chronic colitis. Immunohistochemistry analysis revealed high expression of CXCL13 in the colon tissues of patients with UC, showing a positive correlation with APN, COL1A1, and COL3A1.

CONCLUSION

APN contributes to the progression of colonic fibrosis and can exacerbate this condition by regulating the secretion of CXCL13 in the colon, offering potential new perspectives on the pathophysiology of colonic fibrosis.

Diverse Cytokines Secreted by Adipocyte in Linking Cardio-Metabolic Disorder and SLE

Systemic lupus erythematosus (SLE) is a multi-factorial autoimmune-mediated disease with hyper-stimulation of immune cells especially the T lymphocytes. By this method, it might facilitate the systematic damages in multiple tissues and organs. Otherwise, SLE is also correlated with diverse cardio-metabolic comorbidities, including dyslipidemia, insulin resistance, and hypertension. It is worth-noting that the risk of cardio-metabolic disorders is significantly higher compared with the healthy patients which was reported as approximately one-third of SLE patients were proved as obesity. Notably, current focus is shifting to implementing cardio-metabolic protective strategies as well as elucidating underlying mechanisms of lupus-mediated obese status. On the other hand, adipocyte, as the most abundant endocrine cell in fat tissue, are dysfunctional in obese individuals with aberrant secretion of adipokines. It is proposing that the adipokine might link the pathology of cardio-metabolic disorders and SLE, whereas the related mechanism is complicated. In the current review, the functions of adipokine and the potential mechanisms by which the adipokine link cardio-metabolic disorders and SLE was well listed. Furthermore, the recommendations, which identify the adipokine as the potential therapeutic targets for the treatment of cardio-metabolic disorders and SLE, were also summarized.

Association of adipose tissue inflammation and physical fitness in older adults

An active lifestyle is of key importance for reduction of obesity and inflammation, as well as circulating levels of adipokines. Therefore, the aim of our study was to assess the relationship of physical fitness with chronic inflammatory status, and to evaluate biomarkers useful in the analysis of adipose tissue dysfunction. Sixty-three older adults (69.6 ± 5.1 years) were allocated to a high n = 31 (women n = 23 and men n = 8 male) or low physical fitness n = 32 (women n = 29 and men n = 3) group based on gait speed values (1.4-1.8 m/s or ≤ 1.3 m/s). The gait speed correlated with hand grip strength (rs = 0.493, p = 0.0001) and with leptin level (R = -0.372, p = 0.003), which shows the benefits of physical activity on muscle strength and circulating adipokines. In low physical fitness group, 58.1% individuals had adiponectin to leptin ratio (Adpn/Lep) < 0.5 revealing dysfunction of adipose tissue and high cardiometabolic risk; 20% of the group were obese with BMI ≥ 30 kg/m2. In high physical fitness group, 25.8% of individuals had Adpn/Lep ≥ 1.0 i.e., within the reference range. Markers of systemic inflammation were significantly related to physical fitness: CRP/gait speed (rs = -0.377) and HMGB-1/gait speed (rs = -0.264). The results of the ROC analysis for Adpn (AUC = 0.526), Lep (AUC = 0.745) and HMGB-1 (AUC = 0.689) indicated their diagnostic potential for clinical prognosis in older patients. The optimal threshold values corresponded to 1.2 μg/mL for Adpn (sensitivity 74.2%, specificity 41.9%, OR = 1.4, 95%Cl 0.488-3.902), 6.7 ng/mL for Lep (sensitivity 56.2%, specificity 93.5%, OR = 14.8, 95%Cl 3.574-112.229), 2.63 mg/L for CRP (sensitivity 51.6%, specificity 84.3%, OR = 4.4, 95% Cl 1.401- 16.063) and 34.2 ng/mL for HMGB-1 (sensitivity 62.0%, specificity 86.6%, OR = 12.0, 95%Cl 3.254-61.614). The highest sensitivity and specificity were observed for Leptin and HMGB-1. The study revealed changes in inflammatory status in older adults at various levels of physical fitness and demonstrated diagnostic usefulness of adipokines in the assessment of adipose tissue inflammation.

The Role of Adipose Tissue and Nutrition in the Regulation of Adiponectin

Adipose tissue (AT), composed mainly of adipocytes, plays a critical role in lipid control, metabolism, and energy storage. Once considered metabolically inert, AT is now recognized as a dynamic endocrine organ that regulates food intake, energy homeostasis, insulin sensitivity, thermoregulation, and immune responses. This review examines the multifaceted role of adiponectin, a predominant adipokine released by AT, in glucose and fatty acid metabolism. We explore the regulatory mechanisms of adiponectin, its physiological effects and its potential as a therapeutic target for metabolic diseases such as type 2 diabetes, cardiovascular disease and fatty liver disease. Furthermore, we analyze the impact of various dietary patterns, specific nutrients, and physical activities on adiponectin levels, highlighting strategies to improve metabolic health. Our comprehensive review provides insights into the critical functions of adiponectin and its importance in maintaining systemic metabolic homeostasis.

Circulating levels of C1q/TNF-α-related protein 6 (CTRP6) in coronary artery disease and its correlation with inflammatory markers

Introduction

Circulating levels of C1q/TNF-α-related protein 6 (CTRP6) is an adipokine that is involved in regulation of glucose and lipid metabolism, inflammation, and insulin sensitivity. However, the exact role of CTRP6 in metabolic processes remains unclear due to conflicting findings. To address current gap, we aimed to investigate the serum levels of CTRP6 in patients with coronary artery disease (CAD) and its association with inflammatory cytokines.

Method

In this case-control study, the serum levels of CTRP6, interlukin-6 (IL-6), tumor necrosis factor- α (TNF-α), adiponectin, and fasting insulin were measured using enzyme-linked immunosorbent assay (ELISA) kits in a total of 176 participants, consisting of 88 CAD patients and 88 control subjects. Additionally, various anthropometric and biochemical measurements were measured and compared between cases and controls.

Results

The present study found that serum levels of CTRP6 were significantly higher in the CAD group (561.3 ± 15.14) compared to the control group (429.3 ± 12.85, p < 0.001). After adjusting for age, sex, and body mass index (BMI), CTRP6 levels were found to be positively associated with the risk of CAD (p < 0.001). Correlation analysis in CAD subjects revealed a positive correlation between CTRP6 levels and BMI, systolic blood pressure (SBP), malondialdehyde (MDA), TNF-α, and IL-6, as well as a negative correlation with creatinine and total anti-oxidant capacity.

Conclusion

The findings of this study provide novel evidence that elevated serum levels of CTRP6 are significantly associated with an increased risk of developing CAD. Moreover, our results indicate a correlation between CTRP6 and various risk factors for atherosclerosis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-024-01415-5.

Exploring exercise-driven exerkines: unraveling the regulation of metabolism and inflammation

Exercise has many beneficial effects that provide health and metabolic benefits. Signaling molecules are released from organs and tissues in response to exercise stimuli and are widely termed exerkines, which exert influence on a multitude of intricate multi-tissue processes, such as muscle, adipose tissue, pancreas, liver, cardiovascular tissue, kidney, and bone. For the metabolic effect, exerkines regulate the metabolic homeostasis of organisms by increasing glucose uptake and improving fat synthesis. For the anti-inflammatory effect, exerkines positively influence various chronic inflammation-related diseases, such as type 2 diabetes and atherosclerosis. This review highlights the prospective contribution of exerkines in regulating metabolism, augmenting the anti-inflammatory effects, and providing additional advantages associated with exercise. Moreover, a comprehensive overview and analysis of recent advancements are provided in this review, in addition to predicting future applications used as a potential biomarker or therapeutic target to benefit patients with chronic diseases.

Development of a rapid and ultrasensitive magnetic chemiluminescence immunoassay for the detection of adiponectin and its clinical application

Adiponectin (ADPN), which serum/plasma adiponectin levels are closely associated with insulin resistance and type 2 diabetes, and lower adiponectin levels predict an increased risk of diabetes, is a strong indicator of diabetes risk in people at high risk of diabetes in different races. Using the unique principle and performance advantages of chemiluminescence immunoassay (CLIA), an ADPN-CLIA method with high sensitivity, high specificity and wide detection range was established based on the principle of two-steps method of sandwich-type, with the magnetic particles (MPs) as the solid phase carrier and acridinium ester (AE) as the chemiluminescence reaction system. The selection of the main raw materials required, the preparation conditions of MPs-coated antibodies, the methods of AE-labeled antibodies, sample requirements and reaction modes were optimized and evaluated. AE labeling experiment was successfully performed with the labeling efficiency of 8.366 and the antibody utilization rate of 96.8%. The chemiluminescent immunoassay for ADPN had a good linear relationship from 0 ng/mL to 250 ng/mL (R2 =0.9993), with the detection limit of 0.05 ng/mL. The coefficient of variation (CV) of intra-assay and inter-assay precision were both less than 5% respectively. The recovery rates for accuracy were from 91.26% to 107.46%. The comparison experiment of 80 clinical serum samples between the developed ADPN-CLIA with the immunoturbidimetry showed that the correlation coefficient was 0.956, and the Bland-Altman analysis showed that the limits of agreement were - 0.364 and 0.433.

A Narrative Review on Adipose Tissue and Overtraining: Shedding Light on the Interplay among Adipokines, Exercise and Overtraining

Lifestyle factors, particularly physical inactivity, are closely linked to the onset of numerous metabolic diseases. Adipose tissue (AT) has been extensively studied for various metabolic diseases such as obesity, type 2 diabetes, and immune system dysregulation due to its role in energy metabolism and regulation of inflammation. Physical activity is increasingly recognized as a powerful non-pharmacological tool for the treatment of various disorders, as it helps to improve metabolic, immune, and inflammatory functions. However, chronic excessive training has been associated with increased inflammatory markers and oxidative stress, so much so that excessive training overload, combined with inadequate recovery, can lead to the development of overtraining syndrome (OTS). OTS negatively impacts an athlete's performance capabilities and significantly affects both physical health and mental well-being. However, diagnosing OTS remains challenging as the contributing factors, signs/symptoms, and underlying maladaptive mechanisms are individualized, sport-specific, and unclear. Therefore, identifying potential biomarkers that could assist in preventing and/or diagnosing OTS is an important objective. In this review, we focus on the possibility that the endocrine functions of AT may have significant implications in the etiopathogenesis of OTS. During physical exercise, AT responds dynamically, undergoing remodeling of endocrine functions that influence the production of adipokines involved in regulating major energy and inflammatory processes. In this scenario, we will discuss exercise about its effects on AT activity and metabolism and its relevance to the prevention and/or development of OTS. Furthermore, we will highlight adipokines as potential markers for diagnosing OTS.

Effects of Aerobic Exercise on Serum Adiponectin Concentrations in Children and Adolescents with Obesity: A Systematic Review and Meta-Analysis

Serum adiponectin plays a vital role in various physiological processes, such as anti-inflammatory, anti-atherosclerotic, anti-apoptotic and pro-angiogenic activities. Any abnormalities in its concentration can lead to adverse health outcomes, particularly in children and adolescents. Therefore, it is crucial to investigate factors influencing serum adiponectin concentrations in this population. The primary objective of this study was to systematically evaluate the impact of aerobic exercise on serum adiponectin concentrations in children and adolescents with obesity. To achieve this, a comprehensive literature search was conducted up to January 2023, utilising five databases: PubMed, Web of Science, Embase, Cochrane Library and Clinicaltrial.gov. The inclusion criteria involved studies that focused solely on aerobic exercise as an intervention for children and adolescents with obesity. Only studies that reported outcome indicators related to serum adiponectin were considered for analysis. The quality of the included studies was assessed using the Cochrane Risk of Bias (ROB) assessment tool, and statistical analysis was performed using RevMan 5.4.1 analysis software. This meta-analysis incorporated data from eight trials, involving a total of 272 subjects. The results demonstrated that aerobic training significantly increased serum adiponectin concentrations [standardized mean difference (SMD) = 0.85; 95% confidence interval (CI) = 0.33 to 1.37; I2 = 0%; p = 0.001] in children and adolescents with obesity when compared to non-exercise controls. Furthermore, the magnitude of this effect appears to be influenced by the intensity of aerobic exercise, with higher-intensity aerobic exercise resulting in greater increases in serum adiponectin concentrations.