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Arteriosclerosis, Thrombosis, and... Nov 2019Perivascular adipocytes residing in the vascular adventitia are recognized as distinct endocrine cells capable of responding to inflammatory stimuli and communicating... (Review)
Review
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.
Topics: Adipocytes; Adipokines; Animals; Computed Tomography Angiography; Endothelium, Vascular; Humans; Obesity; Phenotype; Signal Transduction; Vascular Diseases; Vasoconstriction; Vasodilation
PubMed: 31510794
DOI: 10.1161/ATVBAHA.119.312304 -
Frontiers in Endocrinology 2023Circulating adipokines and ghrelin affect bone remodeling by regulating the activation and differentiation of osteoblasts and osteoclasts. Although the correlation... (Meta-Analysis)
Meta-Analysis
CONTEXT
Circulating adipokines and ghrelin affect bone remodeling by regulating the activation and differentiation of osteoblasts and osteoclasts. Although the correlation between adipokines, ghrelin, and bone mineral density (BMD) has been studied over the decades, its correlations are still controversial. Accordingly, an updated meta-analysis with new findings is needed.
OBJECTIVE
This study aimed to explore the impact of serum adipokine and ghrelin levels on BMD and osteoporotic fractures through a meta-analysis.
DATA SOURCES
Studies published till October 2020 in Medline, Embase, and the Cochrane Library were reviewed.
STUDY SELECTION
We included studies that measured at least one serum adipokine level and BMD or fracture risk in healthy individuals. We excluded studies with one or more of the following: patients less than 18 years old, patients with comorbidities, who had undergone metabolic treatment, obese patients, patients with high physical activities, and a study that did not distinguish sex or menopausal status.
DATA EXTRACTION
We extracted the data that include the correlation coefficient between adipokines (leptin, adiponectin, and resistin) and ghrelin and BMD, fracture risk by osteoporotic status from eligible studies.
DATA SYNTHESIS
A meta-analysis of the pooled correlations between adipokines and BMD was performed, demonstrating that the correlation between leptin and BMD was prominent in postmenopausal women. In most cases, adiponectin levels were inversely correlated with BMD. A meta-analysis was conducted by pooling the mean differences in adipokine levels according to the osteoporotic status. In postmenopausal women, significantly lower leptin (SMD = -0.88) and higher adiponectin (SMD = 0.94) levels were seen in the osteoporosis group than in the control group. By predicting fracture risk, higher leptin levels were associated with lower fracture risk (HR = 0.68), whereas higher adiponectin levels were associated with an increased fracture risk in men (HR = 1.94) and incident vertebral fracture in postmenopausal women (HR = 1.18).
CONCLUSIONS
Serum adipokines levels can utilize to predict osteoporotic status and fracture risk of patients.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021224855, identifier CRD42021224855.
Topics: Male; Humans; Female; Adolescent; Bone Density; Leptin; Adipokines; Adiponectin; Ghrelin; Osteoporotic Fractures
PubMed: 37181034
DOI: 10.3389/fendo.2023.1044039 -
Chinese Medical Journal Aug 2023Sarcopenia is an age-related disease that mainly involves decreases in muscle mass, muscle strength and muscle function. At the same time, the body fat content increases...
Sarcopenia is an age-related disease that mainly involves decreases in muscle mass, muscle strength and muscle function. At the same time, the body fat content increases with aging, especially the visceral fat content. Adipose tissue is an endocrine organ that secretes biologically active factors called adipokines, which act on local and distant tissues. Studies have revealed that some adipokines exert regulatory effects on muscle, such as higher serum leptin levels causing a decrease in muscle function and adiponectin inhibits the transcriptional activity of Forkhead box O3 (FoxO3) by activating peroxisome proliferators-activated receptor-γ coactivator -1α (PGC-1α) and sensitizing cells to insulin, thereby repressing atrophy-related genes (atrogin-1 and muscle RING finger 1 [MuRF1]) to prevent the loss of muscle mass. Here, we describe the effects on muscle of adipokines produced by adipose tissue, such as leptin, adiponectin, resistin, mucin and lipocalin-2, and discuss the importance of these adipokines for understanding the development of sarcopenia.
Topics: Humans; Adipokines; Leptin; Adiponectin; Sarcopenia; Muscles
PubMed: 37442757
DOI: 10.1097/CM9.0000000000002255 -
Neurobiology of Aging Dec 2019Aberrant insulin and adipokine signaling has been implicated in cognitive decline associated with both type 2 diabetes mellitus and neurodegenerative diseases. We...
Aberrant insulin and adipokine signaling has been implicated in cognitive decline associated with both type 2 diabetes mellitus and neurodegenerative diseases. We established methods that reliably measure insulin, adiponectin and leptin signaling, and their crosstalk, in thawed postmortem mid-frontal cortical tissue from cognitively normal older subjects with a short postmortem interval. Insulin-evoked insulin receptor (IR) activation increases activated, tyrosine-phosphorylated IRβ on tyrosine residues 960, 1150, and 1151, insulin receptor substrate-1 recruitment to IRβ and phosphorylated RAC-α-serine/threonine-protein kinase. Adiponectin augments, but leptin inhibits, insulin signaling. Adiponectin activates adiponectin receptors to induce APPL1 binding to adiponectin receptor 1 and 2 and T-cadherin and downstream adenosine monophosphate-dependent protein kinase phosphorylation. Insulin inhibited adiponectin-induced signaling. In addition, leptin-induced leptin receptor (OB-R) signaling promotes Janus kinase 2 recruitment to OB-R and Janus kinase 2 and downstream signal transducer and activator of transcription 3 phosphorylation. Insulin enhanced leptin signaling. These data demonstrate insulin and adipokine signaling interactions in human brain. Future studies can use these methods to examine insulin, adiponectin, and leptin metabolic dysregulation in aging and disease states, such as type 2 diabetes and Alzheimer's disease-related dementias.
Topics: Adipokines; Aging; Brain; Humans; Insulin; Leptin; Postmortem Changes; Signal Transduction
PubMed: 31539648
DOI: 10.1016/j.neurobiolaging.2019.08.012 -
Journal of Cardiovascular Pharmacology... 2023Diabetes is a long-term chronic disease, and cardiovascular disease is the leading cause of death. Diabetic cardiomyopathy (DCM), one of the cardiovascular complications... (Review)
Review
Diabetes is a long-term chronic disease, and cardiovascular disease is the leading cause of death. Diabetic cardiomyopathy (DCM), one of the cardiovascular complications of diabetes, has many uncertain factors. Epicardial fat, as the heart fat bank, functions as fatty tissue and is the heart's endocrine organ. The existence of diabetes affects the distribution of heart fat and promotes the secretion of adipokine. In different pathological conditions, it can promote the secretion of pro-inflammatory adipokine, reactive oxygen species, oxidative stress, and even autophagy, thus affecting cardiac function. In this paper, we will elaborate on the mechanism of epicardial fat in the pathogenesis of diabetic cardiomyopathy.
Topics: Humans; Diabetic Cardiomyopathies; Adipose Tissue; Pericardium; Cardiovascular Diseases; Adipokines; Diabetes Mellitus
PubMed: 36752345
DOI: 10.1177/10742484231151820 -
Cells Jul 2022It is increasingly recognized that hypoxia may develop in adipose tissue as its mass expands. Adipose tissue is also the main reservoir of lipophilic pollutants,...
It is increasingly recognized that hypoxia may develop in adipose tissue as its mass expands. Adipose tissue is also the main reservoir of lipophilic pollutants, including polychlorinated biphenyls (PCBs). Both hypoxia and PCBs have been shown to alter adipose tissue functions. The signaling pathways induced by hypoxia and pollutants may crosstalk, as they share a common transcription factor: aryl hydrocarbon receptor nuclear translocator (ARNT). Whether hypoxia and PCBs crosstalk and affect adipokine secretion in human adipocytes remains to be explored. Using primary human adipocytes acutely co-exposed to different levels of hypoxia (24 h) and PCB126 (48 h), we observed that hypoxia significantly inhibits the PCB126 induction of cytochrome P450 (CYP1A1) transcription in a dose-response manner, and that Acriflavine (ACF)-an HIF1α inhibitor-partially restores the PCB126 induction of CYP1A1 under hypoxia. On the other hand, exposure to PCB126 did not affect the transcription of the vascular endothelial growth factor-A (VEGFA) under hypoxia. Exposure to hypoxia increased leptin and interleukin-6 (IL-6), and decreased adiponectin levels dose-dependently, while PCB126 increased IL-6 and IL-8 secretion in a dose-dependent manner. Co-exposure to PCB126 and hypoxia did not alter the adipokine secretion pattern observed under hypoxia and PCB126 exposure alone. In conclusion, our results indicate that (1) hypoxia inhibits PCB126-induced CYP1A1 expression at least partly through ARNT-dependent means, suggesting that hypoxia could affect PCB metabolism and toxicity in adipose tissue, and (2) hypoxia and PCB126 affect leptin, adiponectin, IL-6 and IL-8 secretion differently, with no apparent crosstalk between the two factors.
Topics: Adipocytes; Adipokines; Adiponectin; Aryl Hydrocarbon Receptor Nuclear Translocator; Cytochrome P-450 CYP1A1; Environmental Pollutants; Humans; Hypoxia; Interleukin-6; Interleukin-8; Leptin; Polychlorinated Biphenyls; Vascular Endothelial Growth Factor A
PubMed: 35892579
DOI: 10.3390/cells11152282 -
Adipocyte Dec 2023Adipokines are proteins secreted by adipose tissue to regulate glucolipid metabolism and play vital roles in our body. Different adipokines have more than one endocrine...
Adipokines are proteins secreted by adipose tissue to regulate glucolipid metabolism and play vital roles in our body. Different adipokines have more than one endocrine function and be divided into several different categories according to their functions, including adipokines involved in glucolipid metabolism, the inflammatory response, insulin action, activation of brown adipose tissue (BAT) and appetite regulation. Multiple adipokines interact with each other to regulate metabolic processes. Based on the recent progress of adipokine research, this article discusses the role and mechanism of various adipokines in glucolipid metabolism, which may provide new ideas for understanding the pathogenesis and improving the treatment of various metabolic diseases.
Topics: Adipokines; Glucose; Lipid Metabolism; Adipose Tissue; Adipose Tissue, Brown; Energy Metabolism; Leptin
PubMed: 37077042
DOI: 10.1080/21623945.2023.2202976 -
Biomolecules Nov 2022Leptin is an adipokine directly correlated with the proinflammatory obese-associated phenotype. Leptin has been demonstrated to inhibit adipogenesis, promote fat... (Review)
Review
Leptin is an adipokine directly correlated with the proinflammatory obese-associated phenotype. Leptin has been demonstrated to inhibit adipogenesis, promote fat demarcation, promote a chronic inflammatory state, increase insulin sensitivity, and promote angiogenesis. Leptin, a regulator of the immune response, is implicated in the pathology of asthma. Studies involved in the key cell reaction and animal models of asthma have provided vital insights into the proinflammatory role of leptin in asthma. Many studies described the immune cell and related cellular pathways activated by leptin, which are beneficial in asthma development and increasing exacerbations. Subsequent studies relating to animal models support the role of leptin in increasing inflammatory cell infiltration, airway hyperresponsiveness, and inflammatory responses. However, the conclusive effects of leptin in asthma are not well elaborated. In the present study, we explored the general functions and the clinical cohort study supporting the association between leptin and asthma. The main objective of our review is to address the knowns and unknowns of leptin on asthma. In this perspective, the arguments about the different faces of leptin in asthma are provided to picture the potential directions, thus yielding a better understanding of asthma development.
Topics: Animals; Leptin; Cohort Studies; Asthma; Obesity; Adipokines
PubMed: 36551211
DOI: 10.3390/biom12121780 -
Journal of Atherosclerosis and... 2011Dysregulation of adipose tissue-derived bioactive molecules, termed adipokines, is recognized as common ground for insulin resistance and metabolic syndrome associated... (Review)
Review
Dysregulation of adipose tissue-derived bioactive molecules, termed adipokines, is recognized as common ground for insulin resistance and metabolic syndrome associated with obesity. However, adipokine dysregulation is paradoxically associated with lipodystrophy and lipoatrophy with aging. In familial partial lipodystrophic syndromes and Hutchinson-Gilford progeria syndrome, both of which are caused by mutations in the LMNA gene, loss of adipose tissue is associated with adipokine dysregulation, insulin resistance, and atherosclerosis, suggesting a critical role of adipose tissue function in controlling whole body energy metabolism, age-related pathologies, and longevity. Centenarians, a model of healthy aging and longevity, are reported to exhibit preserved insulin sensitivity as well as favorable adipokine profiles, particularly high levels of circulating adiponectin. Furthermore, adipose tissue dysfunction indicated by dysregulation of leptin, tumor necrosis factor-α, and adiponectin is associated with poor prognosis in centenarians. In contrast to results obtained for obesity, adipokine dysregulation in centenarians is associated with very low leptin levels, suggesting that age-related lipoatrophy is the major factor for adipose tissue dysfunction at an advanced age. These observations suggest that adipose tissue excess as well as its aging is implicated in the regulation of adipokines, insulin sensitivity, and lifespan in humans.
Topics: Adipokines; Adiponectin; Adipose Tissue; Aged, 80 and over; Aging; Animals; Humans; Insulin; Insulin Resistance; Mice; Mutation; Obesity; Phenotype; Prognosis; Tumor Necrosis Factor-alpha
PubMed: 21551960
DOI: 10.5551/jat.7039 -
Frontiers in Endocrinology 2023
Topics: Humans; Adipokines; Leptin; Obesity; Neoplasms
PubMed: 38107522
DOI: 10.3389/fendo.2023.1340171