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Acta Pharmacologica Sinica May 2016Secreted proteins play critical roles in physiological and pathological processes and can be used as biomarkers and therapies for aging and disease. Metrnl is a novel... (Review)
Review
Secreted proteins play critical roles in physiological and pathological processes and can be used as biomarkers and therapies for aging and disease. Metrnl is a novel secreted protein homologous to the neurotrophin Metrn. But this protein, unlike Metrn that is mainly expressed in the brain, shows a relatively wider distribution in the body with high levels of expression in white adipose tissue and barrier tissues. This protein plays important roles in neural development, white adipose browning and insulin sensitization. Based on its expression and distinct functions, this protein is also called Cometin, Subfatin and Interleukin 39, which refer to its neurotrophic effect, adipokine function and the possible action as a cytokine, respectively. The spectrum of Metrnl functions remains to be determined, and the mechanisms of Metrnl action need to be elucidated. In this review, we focus on the discovery, structural characteristics, expression pattern and physiological functions of Metrnl, which will assist in developing this protein as a new therapeutic target or agent.
Topics: Adipokines; Adipose Tissue, Brown; Adipose Tissue, White; Animals; Humans; Insulin Resistance; Intercellular Signaling Peptides and Proteins; Nerve Growth Factors; Nerve Tissue Proteins; Organ Specificity
PubMed: 27063217
DOI: 10.1038/aps.2016.9 -
Obesity Facts 2019Increasing prevalence of obesity requires the investigation of respective comorbidities, including tumor diseases like colorectal, renal, post-menopausal breast,... (Review)
Review
BACKGROUND
Increasing prevalence of obesity requires the investigation of respective comorbidities, including tumor diseases like colorectal, renal, post-menopausal breast, prostate cancer, and leukemia. To date, molecular mechanisms of the malignant transformation of these peripheral tissues induced by obesity remain unclear. Adipose tissue secretes factors with hormone-like functions, the adipokines, and is therefore categorized as an endocrine organ. Current research demonstrates the ability of adipose tissue to alter DNA methylation and gene expression in peripheral tissues, probably affecting microRNA (miR) expression.
METHODS
Literature was analyzed for adipokine-regulated miRs. Many of these adipokine upregulated or downregulated miRs exert either oncogenic or anti-tumoral potential.
RESULTS
The three selected and analyzed adipokines, adiponectin, leptin, and resistin, induce more strongly oncogenic miRs and simultaneously reduce anti-tumoral miRs than vice versa. This effect is not only true for the pure number of regulated miRs, it is also the case by consideration of the abundance of the respective miR expression based on actual data sets derived from next-generation sequencing.
CONCLUSION
The link of obesity and cancer is analyzed under the aspect of adipokine-regulated miRs. At the same time the impact of miR abundance is considered as a regulatory variable. This context offers new strategies for tumor therapy and diagnostics.
Topics: Adipokines; Adipose Tissue; Female; Gene Expression Regulation, Neoplastic; Genes, Tumor Suppressor; Humans; Leptin; Male; MicroRNAs; Neoplasms; Obesity; Oncogenes
PubMed: 30999294
DOI: 10.1159/000496625 -
BMC Endocrine Disorders Feb 2022Bariatric surgery is considered to be the most effective treatment option for weight reduction in obese patients. Abdominal obesity is frequently accompanied by...
BACKGROUND
Bariatric surgery is considered to be the most effective treatment option for weight reduction in obese patients. Abdominal obesity is frequently accompanied by metabolic syndrome (MS). Adipokines are cell signaling proteins that have direct impact upon the metabolic homeostasis. The purpose of this analysis was to evaluate the effect of bariatric surgery, including laparoscopic sleeve gastrectomy (LSG) and laparoscopic gastric bypass (LRYGB) on the adipokine levels and metabolic profile as well as MS and status of type 2 diabetes (T2D).
METHODS
We analyzed anthropometric parameters, blood levels of adipokines, vitamins, lipids and inflammatory markers in 30 bariatric surgery patients with obesity of class II or III 1 month before and 1 year after surgery as well as in 60 obese patients from general practice (GP) and 15 patients with normal body mass (control).
RESULTS
The BMI was significantly higher among patients before surgery and GP patients in comparison to control and post-surgery patients. The levels of glucose, cholesterol and LDL-cholesterol, triglyceride and hs-CRP were the highest in patients before surgery but decreased significantly after surgery, while the level of HDL-cholesterol increased after surgery. The levels of adiponectin increased and that of leptin decreased after surgery. The significant difference in the concentration of resistin was revealed between LSG and LRYGB methods. The relationship between resistin and vitamin D was also found. The patients with MS and T2D displayed significantly greater reduction in lipid markers and adipokine levels than the rest of patients.
CONCLUSION
Remarkable changes in levels of adipokines after bariatric surgery appear like increase in adiponectin and decrease in leptin levels. Significant improvement in anthropometric parameters, metabolic and inflammatory markers occurs, suggesting high potential for reduction of metabolic syndrome and risk for type 2 diabetes. We have shown for the first time ever that level of vitamin D may be involved in resistin regulation.
Topics: Adipokines; Adult; Aged; Bariatric Surgery; Biomarkers; Diabetes Mellitus, Type 2; Female; Humans; Lipids; Male; Middle Aged; Obesity, Morbid; Vitamins
PubMed: 35114975
DOI: 10.1186/s12902-022-00942-7 -
International Journal of Molecular... Sep 2019Chemerin is widely recognized as an adipokine, with diverse biological roles in cellular differentiation and metabolism, as well as a leukocyte chemoattractant. Research... (Review)
Review
Chemerin is widely recognized as an adipokine, with diverse biological roles in cellular differentiation and metabolism, as well as a leukocyte chemoattractant. Research investigating the role of chemerin in the obesity-cancer relationship has provided evidence both for pro- and anti-cancer effects. The tumor-promoting effects of chemerin primarily involve direct effects on migration, invasion, and metastasis as well as growth and proliferation of cancer cells. Chemerin can also promote tumor growth via the recruitment of tumor-supporting mesenchymal stromal cells and stimulation of angiogenesis pathways in endothelial cells. In contrast, the majority of evidence supports that the tumor-suppressing effects of chemerin are immune-mediated and result in a shift from immunosuppressive to immunogenic cell populations within the tumor microenvironment. Systemic chemerin and chemerin produced within the tumor microenvironment may contribute to these effects via signaling through CMKLR1 (chemerin), GPR1 (chemerin), and CCLR2 on target cells. As such, inhibition or activation of chemerin signaling could be beneficial as a therapeutic approach depending on the type of cancer. Additional studies are required to determine if obesity influences cancer initiation or progression through increased adipose tissue production of chemerin and/or altered chemerin processing that leads to changes in chemerin signaling in the tumor microenvironment.
Topics: Adipokines; Animals; Biomarkers; Chemokines; Disease Susceptibility; Humans; Immunomodulation; Neoplasms; Obesity; Organ Specificity; Protein Binding; Signal Transduction
PubMed: 31561459
DOI: 10.3390/ijms20194778 -
Annales de Biologie Clinique Jun 2020The identification of leptin allowed the discovery of a new endocrine system. This major adipokine controlling energy homeostasis is also involved in the regulation of... (Review)
Review
The identification of leptin allowed the discovery of a new endocrine system. This major adipokine controlling energy homeostasis is also involved in the regulation of neuroendocrine function and fertility. Unfortunately, leptin is not able to treat common obesity, which associates hyperleptinemia and resistance to the hormone. Conversely, treatment with recombinant leptin is effective in situations of leptin deficiency. Several pathophysiological situations associated with adipose tissue dysfunctions and abnormal regulation of leptin secretion are discussed in this review. The advantage of the potential use of the leptin assay in some pathophysiological conditions is proposed.
Topics: Adipokines; Adipose Tissue; Animals; Homeostasis; Humans; Leptin; Obesity; Secretory Pathway
PubMed: 32540812
DOI: 10.1684/abc.2020.1560 -
International Journal of Molecular... Mar 2024The co-occurrence of asthma and obesity is becoming an increasingly common health problem. It became clear that both diseases are closely related, since... (Review)
Review
The co-occurrence of asthma and obesity is becoming an increasingly common health problem. It became clear that both diseases are closely related, since overweight/obesity are associated with an increased risk of asthma development, and more than half of the subjects with severe or difficult-to-treat asthma are obese. Currently, there are no specific guidelines for the treatment of this group of patients. The mechanisms involved in the asthma-obesity phenotype include low-grade chronic inflammation and changes in pulmonary physiology. However, genetic predispositions, gender differences, comorbid conditions, and gut microbiota also seem to be important. Regulatory peptides affect many processes related to the functioning of the respiratory tract and adipose tissue. Adipokines such as leptin, adiponectin, resistin, and the less studied omentin, chemerin, and visfatin, as well as the gastrointestinal hormones ghrelin, cholecystokinin, glucagon-like peptide-1, and neuropeptides, including substance P or neuropeptide Y, can play a significant role in asthma with obesity. The aim of this article is to provide a concise review of the contribution of particular peptides in inflammatory reactions, obesity, asthma, and a combination of both diseases, as well as emphasize their potential role in the effective treatment of the asthma-obesity phenotype in the future.
Topics: Humans; Leptin; Obesity; Adipokines; Adipose Tissue; Adiponectin; Asthma; Phenotype
PubMed: 38542187
DOI: 10.3390/ijms25063213 -
International Journal of Molecular... Oct 2020It 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... (Review)
Review
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.
Topics: Adipokines; Adipose Tissue; Animals; Cardiovascular Diseases; Humans; Inflammation
PubMed: 33081064
DOI: 10.3390/ijms21207711 -
JPMA. the Journal of the Pakistan... Apr 2023Adipose tissue or fat tissue is a loose connective tissue that consists mainly of adipocytes. Adipocytes are classified on the basis of their secretory origin,... (Review)
Review
Adipose tissue or fat tissue is a loose connective tissue that consists mainly of adipocytes. Adipocytes are classified on the basis of their secretory origin, differentiation, distribution, cell characteristics, such as amount of mitochondria, size and type of lipid droplets, and expression of uncoupled protein-1. Adipocytes secrete adipokines that are divided as white adipokines, brown adipokines and beige adipokines. Adipokines have been used as diagnostic and prognostic markers for different oral diseases. Irisin, chemerin, resistin, adiponectin, zinc alpha 2 macroglobulin, leptin, visfatin, tumour necrosis factor-alpha and interleukin-6 are some important adipokines associated with oral diseases, such as dental caries, periodontal diseases, recurrent aphthous stomatitis, oral cancers, oral premalignant lesions, Sjogren's syndrome, Kawasaki disease and Behcet's disease. The current narrative review was planned to focus on the pathophysiological role of adipokines in oral diseases and their role as biomarkers for early diagnosis and prompt treatment.
Topics: Humans; Adipokines; Dental Caries; Prognosis; Leptin; Adipose Tissue; Adiponectin
PubMed: 37052000
DOI: 10.47391/JPMA.4737 -
International Journal of Molecular... Mar 2022White adipose tissue (WAT) is a specialized tissue whose main function is lipid synthesis and triglyceride storage. It is now considered as an active organ secreting a... (Review)
Review
White adipose tissue (WAT) is a specialized tissue whose main function is lipid synthesis and triglyceride storage. It is now considered as an active organ secreting a plethora of hormones and cytokines namely adipokines. Discovered in 1994, leptin has emerged as a key molecule with pleiotropic functions. It is primarily recognized for its role in regulating energy homeostasis and food intake. Currently, further evidence suggests its potent role in reproduction, glucose metabolism, hematopoiesis, and interaction with the immune system. It is implicated in both innate and adaptive immunity, and it is reported to contribute, with other adipokines, in the cross-talking networks involved in the pathogenesis of chronic inflammation and immune-related diseases of the musculo-skeletal system such as osteoarthritis (OA) and rheumatoid arthritis (RA). In this review, we summarize the most recent findings concerning the involvement of leptin in immunity and inflammatory responses in OA and RA.
Topics: Adipokines; Arthritis, Rheumatoid; Humans; Immune System Diseases; Inflammation; Leptin; Osteoarthritis
PubMed: 35270000
DOI: 10.3390/ijms23052859 -
Nutrients Nov 2022The mineralocorticoid receptor (MR) acts as an essential regulator of blood pressure, volume status, and electrolyte balance. However, in recent decades, a growing body... (Review)
Review
The mineralocorticoid receptor (MR) acts as an essential regulator of blood pressure, volume status, and electrolyte balance. However, in recent decades, a growing body of evidence has suggested that MR may also have a role in mediating pro-inflammatory, pro-oxidative, and pro-fibrotic changes in several target organs, including the adipose tissue. The finding that MR is overexpressed in the adipose tissue of patients with obesity has led to the hypothesis that this receptor can contribute to adipokine dysregulation and low-grade chronic inflammation, alterations that are linked to the development of obesity-related metabolic and cardiovascular complications. Moreover, several studies in animal models have investigated the role of MR antagonists (MRAs) in preventing the metabolic alterations observed in obesity. In the present review we will focus on the potential mechanisms by which MR activation can contribute to adipose tissue dysfunction in obesity and on the possible beneficial effects of MRAs in this setting.
Topics: Animals; Receptors, Mineralocorticoid; Adipose Tissue; Obesity; Adipokines; Blood Pressure
PubMed: 36432422
DOI: 10.3390/nu14224735