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Hypercholesterolemia is characterized by elevated low-density lipoprotein (LDL)-cholesterol levels and an increased risk of cardiovascular disease. The adipokine chemerin is an additional risk factor. Here we investigated whether cholesterol-lowering with statins or proprotein convertase subtilisin-kexin type 9 inhibitors (PCSK9i) affects chemerin. Both statins and PCKS9i lowered plasma LDL-cholesterol, triglycerides and total cholesterol in hypercholesterolemic patients, and increased high-density lipoprotein (HDL)-cholesterol. Yet, only statins additionally reduced chemerin and high-sensitivity C-reactive protein (hsCRP). Applying PCSK9i on top of statins did not further reduce chemerin. Around 20% of chemerin occurred in the HDL2/HDL3 fractions, while >75% was free. Statins lowered both HDL-bound and free chemerin. Pull-down assays revealed that chemerin binds to the HDL-component Apolipoprotein A-I (ApoA-I). The statins, but not PCSK9i, diminished chemerin secretion from HepG2 cells by upregulating LDL receptor mRNA. Furthermore, chemerin inhibited HDL-mediated cholesterol efflux via its chemerin chemokine-like receptor 1 in differentiated macrophages. In conclusion, statins, but not PCSK9i, lower circulating chemerin by directly affecting its release from hepatocytes. Chemerin binds to ApoA-I and inhibits HDL-mediated cholesterol efflux. Statins prevent this by lowering HDL-bound chemerin. Combined with their anti-inflammatory effect evidenced by hsCRP suppression, this represents a novel cardiovascular protective function of statins that distinguishes them from PCSK9i.
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Chemerin is a distant member of the cystatin protein family, initially discovered as a chemotactic factor and subsequently also reported to act as adipokine and angiogenetic factor. The biological activity of chemerin is regulated at different levels, such as gene expression, protein processing and interaction with both signaling and nonsignaling receptors. Chemerin is mostly produced by stromal cells, such as adipocytes, fibroblasts, epithelial and endothelial cells and circulates in almost all human tissues as a zymogen that needs to be proteolytically activated to exert its biological functions. At the receptor level, chemerin binds a G protein-coupled seven transmembrane domain receptor Chemerin1 (also named ChemR23 and CMKLR1), mostly expressed by innate immune cells, such as macrophages, dendritic cells and NK cells and by border cells. In addition, chemerin may bind GPR1, a weak signaling receptor, and CCRL2, a nonsignaling receptor expressed by barrier cells, such as endothelial and epithelial cells, able to regulate leukocytes migration by multiple mechanisms. The aim of this review is to summarize the contribution of chemerin in the regulation of immune responses.
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Interactions between female metabolic status, immune response, and reproductive system functioning are complex and not fully understood. We hypothesized that chemerin, considered a hormonal link between the above-mentioned processes, influences endometrial functions, particularly cytokine secretion and signalling. Using porcine endometrial explants collected during early pregnancy and the estrous cycle, we investigated chemerin effects on the secretion of interleukins (IL-1ß, IL-6, IL-8), leukaemia inhibitory factor (LIF), tumour necrosis factor α (TNFα), transforming growth factor α (TGFα), and protein abundances of their respective receptors. Our results demonstrate chemerin modulation of cytokine secretion and receptor expression, with effects dependent on the stage of pregnancy and dose of chemerin. Furthermore, chemerin influences the phosphorylation of stress-activated protein kinase/Jun-amino-terminal kinase (SAPK/JNK) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κß) in the endometrium. Chemerin multifaceted actions, such as involvement in immune response, cell proliferation, and tissue remodelling seem to be mediated by cytokines, at least in the endometrium. These findings underscore the potential crosstalk between chemerin and hormonal signalling pathways, providing insights into the complex mechanisms underlying early pregnancy establishment and maintenance.
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Chemerin and resistin are adipokines studied as potential markers for early diagnosis and disease severity in patients with knee osteoarthritis (KOA) Therefore, we aimed to investigate the associations serum and synovial levels of chemerin and resistin with inflammatory parameters and ultrasonographic scores (US) in KOA individuals. Serum was collected from 28 patients with KOA and synovial fluid was obtained from 16 of them. Another 31 age and sex matched cases with no joint disease were included as healthy controls. Concentrations of chemerin, resistin, interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) were determined with ELISA. Erythrocyte sedimentation rate (ESR), C-reactive protein, serum uric acid (UA) were measured in the patients group. Participants with KOA underwent US assessment using the Outcome Measures in Rheumatology (OMERACT) scores. Patients with KOA had statistically significant higher level of serum resistin than healthy controls [11.05 (3.78-24.13) ng/mL and 7.23 (3.83-12.19) respectively, p < 0.001]. A strong correlation was found between serum chemerin and ESR (r = 0.434, p = 0.021), uric acid (r = 0.573, p = 0.001) as well as the US (r=-0.872, p < 0.001). Serum resistin demonstrated significant association with TNF-alpha (r = 0.398, p = 0.044). In conclusion, both chemerin and resistin might contribute to inflammatory changes associated with KOA. Further studies are needed to elucidate their potential role in the pathogenesis of the disease.
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Objectives: Chemerin, as a novel multifunctional adipokine, is proposed to be involved in high cancer risk and mortality. The present study was aimed to evaluate the prognostic value of serum Chemerin and neutrophils in patients with oral squamous cell carcinoma (OSCC). Materials and methods: 120 patients with OSCC were included in this prospective cohort study. The levels of serum Chemerin were measured by enzyme-linked immunosorbent assay (ELISA). We also explored the possible effects of Chemerin on neutrophils' chemokines in OSCC using a real-time PCR, western blotting. Results: Levels of serum Chemerin, neutrophils and NLR were significantly higher among non-survivors compared to survivors of OSCC (both P < 0.05). Higher serum Chemerin levels were associated with advanced TNM stage, lymph node metastasis, differentiation and tumor recurrence (both P < 0.05). Serum Chemerin levels correlated with neutrophils and NLR levels (r = 0.708, r = 0.578, both P < 0.05). Based on ROC analysis, Chemerin + NLR predicted OSCC patient mortality with 81.54 % sensitivity and 87.27 % specificity, with an AUC of 0.8898. In a Kaplan-Meier analysis, high serum Chemerin levels, high neutrophil levels and high NLR levels were associated with shorter overall and disease-free survival (both P < 0.05). A univariate and multivariate Cox regression analysis showed that serum Chemerin and neutrophils were independent risk factors for OSCC. (both P < 0.05). QRT-PCR and western blotting results showed that Chemerin upregulated the expression of chemokines IL-17 and CXCL-5 in neutrophils (both P < 0.05). Conclusions: Our study suggests that measurement of serum Chemerin and neutrophils might be a useful diagnostic and prognostic biomarker for OSCC patients. Chemerin may promote neutrophils infiltration in OSCC through upregulation of chemokines IL17 and CXCL-5.
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Adipokines play essential roles in regulating a range of biological processes, but growing evidence indicates that they are also fundamental in immunological mechanisms and, primarily, inflammatory responses. Adipokines mediate their actions through specific receptors. However, although adipokine receptors are widely distributed in many cell and tissue types, limited data are available on their expression in mast cells (MCs) and, consequently, adipokine's significance in the modulation of MC activity within the tissues. In this study, we demonstrate that rat peritoneal MCs constitutively express the leptin receptor (i.e. LEPR), adiponectin receptors (i.e. ADIPOR1 and ADIPOR2) and the chemerin receptor (i.e. CMKLR1). We also found that LEPR, ADIPOR1, ADIPOR2 and CMKLR1 expression in MCs changes in response to stimulation by their specific ligands and some cytokines with potent proinflammatory properties. Furthermore, the involvement of intracellular signaling molecules in leptin-, adiponectin- and chemerin-induced MC response was analyzed. Overall, our findings suggest that adipokines leptin, adiponectin and chemerin can significantly affect the activity of MCs in various processes, especially during inflammation. These observations may contribute significantly to understanding the relationship between adipokines, immune mechanisms and diseases or conditions with an inflammatory component.
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BACKGROUND: With aging, white adipose tissue (WAT) undergoes distribution change and browning inhibition, which could be attenuated by exercise. Adipokine chemerin exerts roles in the above changes of WAT, and our previous studies demonstrated the effect of decreased chemerin on exercise-induced improvement of glucose and lipid metabolism in high fat diet (HFD) feeding male mice, so this study is to clarify whether chemerin's effects on glucose and lipid metabolism are associated with the distribution and browning of WAT. METHODS: After diet and exercise interventions, body weight and adipose tissue contents in different depots of male mice were weighed, body composition and energy metabolism parameters were determined by Echo MRI Body Composition Analyzer and metabolic cage, respectively. The levels of serum adiponectin and leptin were detected by ELISA, and the protein levels of PGC-1α, UCP1, adiponectin and leptin in WAT were measured by Western blot. RESULTS: Chemerin knockout exacerbated HFD-induced weight gain, upregulated the increases of visceral and subcutaneous WAT (vWAT and sWAT, especial in sWAT), and inhibited WAT browning, but improved blood lipid. Exercise reduced the body weight and WAT distribution, increased sWAT browning and further improved blood lipid in aged HFD male mice, which were abrogated by chemerin knockout. Detrimental alterations of leptin, adiponectin and adiponectin/leptin ratio were discovered in the serum and WAT of aged HFD chemerin(-/-) mice; and exercise-induced beneficial changes in these adipokines were blocked by chemerin knockout. CONCLUSION: Chemerin influences blood lipid of aged male mice under HFD and exercise states through regulating the distribution and browning of WAT, which might be related to the changes of adiponectin, leptin and adiponectin/leptin ratio.
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Adiponectina , Tecido Adiposo Marrom , Tecido Adiposo Branco , Quimiocinas , Dieta Hiperlipídica , Leptina , Camundongos Knockout , Condicionamento Físico Animal , Animais , Masculino , Tecido Adiposo Branco/metabolismo , Condicionamento Físico Animal/fisiologia , Quimiocinas/metabolismo , Quimiocinas/sangue , Camundongos , Leptina/sangue , Leptina/metabolismo , Adiponectina/metabolismo , Adiponectina/sangue , Tecido Adiposo Marrom/metabolismo , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Lipídeos/sangue , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos Endogâmicos C57BL , Metabolismo dos Lipídeos/fisiologia , Peso Corporal/fisiologia , Metabolismo Energético/fisiologia , Proteína Desacopladora 1/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismoRESUMO
Embryonic mortality is a significant problem in the commercial duck industry worldwide. Therefore, identification of new biomarkers for duck embryo development is necessary. In the chicken (order Galliformes), we previously showed that chemerin is a hormone locally produced by the reproductive tract in hens, particularly in the magnum area, leading to its accumulation in the egg white and within the embryo annexes during embryonic development. We therefore hypothesized that the chemerin concentration in egg white could be a biomarker of egg performance and reproductive parameters in Pekin ducks (order Anseriformes). Thus, we collected eggs from Pekin ducks over a 5-d period at three stages of the laying period (before the laying peak, after the laying peak, and at the end of the laying period) to measure the chemerin concentrations in egg white by enzyme-linked immunosorbent assay. The chemerin concentration in egg white decreased during the laying period and was not associated with reproductive parameters. We found negative correlations between the chemerin level in egg white and the albumen weight. Reverse-transcriptase quantitative polymerase chain reaction showed that chemerin and its three receptors CMKLR1, GPR1, and CCRL2 were expressed in the reproductive tract and within allantoic and amniotic annexes during embryo development. Chemerin concentrations strongly increased in amniotic fluid on embryonic day 16 (ED16) when the egg white was transferred into the amniotic sac. Finally, chemerin inhibition in egg white by in ovo injections of anti-chemerin antibodies (0.01, 0.1, and 1 µg) increased the embryo mortality rate. These data demonstrate the important role of the chemerin system during egg formation and embryo development in Pekin ducks, suggesting their potential use as biomarkers for determining the quality of poultry eggs and embryo development.
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Proteínas Aviárias , Quimiocinas , Patos , Desenvolvimento Embrionário , Animais , Patos/embriologia , Patos/metabolismo , Patos/crescimento & desenvolvimento , Quimiocinas/metabolismo , Quimiocinas/genética , Feminino , Proteínas Aviárias/metabolismo , Proteínas Aviárias/genética , Clara de Ovo/química , Receptores de Quimiocinas/metabolismo , Receptores de Quimiocinas/genética , Biomarcadores/metabolismoRESUMO
Chemerin is an adipokine that contributes to metabolism regulation. Nucleus tractus solitarius (NTS) is the first relay station in the brain for accepting various visceral afferent activities for regulating cardiovascular activity. However, the roles of chemerin in the NTS in regulating sympathetic activity and blood pressure are almost unknown. This study aimed to determine the role and potential mechanism of chemerin in the NTS in modulating sympathetic outflow and blood pressure. Bilateral NTS microinjections were performed in anaesthetized adult male Sprague-Dawley rats. Renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP) and heart rate (HR) were continuously recorded. Chemerin and its receptor chemokine-like receptor 1 (CMKLR1) were highly expressed in caudal NTS (cNTS). Microinjection of chemerin-9 to the cNTS increased RSNA, MAP and HR, which were prevented by CMKLR1 antagonist α-NETA, superoxide scavenger tempol or N-acetyl cysteine, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitors diphenyleneiodonium or apocynin. Chemerin-9 increased superoxide production and NADPH oxidase activity in the cNTS. The increased superoxide production induced by chemerin-9 was inhibited by α-NETA. The effects of cNTS microinjection of chemerin-9 on the RSNA, MAP and HR were attenuated by the pretreatment with paraventricular nucleus (PVN) microinjection of NMDA receptor antagonist MK-801 rather than AMPA/kainate receptor antagonist CNQX. These results indicate that chemerin-9 in the NTS increases sympathetic outflow, blood pressure and HR via CMKLR1-mediated NADPH oxidase activation and subsequent superoxide production in anaesthetized normotensive rats. Glutamatergic inputs in the PVN are needed for the chemerin-9-induced responses.
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Pressão Sanguínea , Quimiocinas , Ratos Sprague-Dawley , Núcleo Solitário , Sistema Nervoso Simpático , Animais , Núcleo Solitário/efeitos dos fármacos , Núcleo Solitário/fisiologia , Núcleo Solitário/metabolismo , Masculino , Quimiocinas/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Sistema Nervoso Simpático/fisiologia , Sistema Nervoso Simpático/efeitos dos fármacos , Ratos , Receptores de Quimiocinas/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , NADPH Oxidases/metabolismo , Superóxidos/metabolismoRESUMO
Induction of beige fat for thermogenesis is a potential therapy to improve homeostasis against obesity. ß3-adrenoceptor (ß3-AR), a type of G protein-coupled receptor (GPCR), is believed to mediate the thermogenesis of brown fat in mice. However, ß3-AR has low expression in human adipose tissue, precluding its activation as a standalone clinical modality. This study aimed at identifying a potential GPCR target to induce beige fat. We found that chemerin chemokine-like receptor 1 (CMKLR1), one of the novel GPCRs, mediated the development of beige fat via its two ligands, chemerin and resolvin E1 (RvE1). The RvE1 levels were decreased in the obese mice, and RvE1 treatment led to a substantial improvement in obese features and augmented beige fat markers. Inversely, despite sharing the same receptor as RvE1, the chemerin levels were increased in obesogenic conditions, and chemerin treatment led to an augmented obese phenotype and a decline of beige fat markers. Moreover, RvE1 and chemerin induced or restrained the development of beige fat, respectively, via the mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway. We further showed that RvE1 and chemerin regulated mTORC1 signaling differentially by forming hydrogen bonds with different binding sites of CMKLR1. In conclusion, our study showed that RvE1 and chemerin affected metabolic homeostasis differentially, suggesting that selectively modulating CMKLR1 may be a potential therapeutic target for restoring metabolic homeostasis.
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The adipokine chemerin contributes to exercise-induced improvements in glucose and lipid metabolism; however, the underlying mechanism remains unclear. We aimed to confirm the impact of reduced chemerin expression on exercise-induced improvement in glycolipid metabolism in male diabetic (DM) mice through exogenous chemerin administration. Furthermore, the underlying mechanism of chemerin involved in changes in muscle mitochondria function mediated by androgen/androgen receptor (AR) was explored by generating adipose-specific and global chemerin knockout (adipo-chemerin-/- and chemerin-/-) mice. DM mice were categorized into the DM, exercised DM (EDM), and EDM + chemerin supplementation groups. Adipo-chemerin-/- and chemerin-/- mice were classified in the sedentary or exercised groups and fed either a normal or high-fat diet. Exercise mice underwent a 6-wk aerobic exercise regimen. The serum testosterone and chemerin levels, glycolipid metabolism indices, mitochondrial function, and protein levels involved in mitochondrial biogenesis and dynamics were measured. Notably, exogenous chemerin reversed exercise-induced improvements in glycolipid metabolism, AR protein levels, mitochondrial biogenesis, and mitochondrial fusion in DM mice. Moreover, adipose-specific chemerin knockout improved glycolipid metabolism, enhanced exercise-induced increases in testosterone and AR levels in exercised mice, and alleviated the detrimental effects of a high-fat diet on mitochondrial morphology, biogenesis, and dynamics. Finally, similar improvements in glucose metabolism (but not lipid metabolism), mitochondrial function, and mitochondrial dynamics were observed in chemerin-/- mice. In conclusion, decreased chemerin levels affect exercise-induced improvements in glycolipid metabolism in male mice by increasing mitochondrial number and function, likely through changes in androgen/AR signaling.NEW & NOTEWORTHY Decreased chemerin levels affect exercise-induced improvements in glycolipid metabolism in male mice by increasing mitochondrial number and function, which is likely mediated by androgen/androgen receptor expression. This study is the first to report the regulatory mechanism of chemerin in muscle mitochondria.
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Quimiocinas , Glucose , Metabolismo dos Lipídeos , Camundongos Knockout , Receptores Androgênicos , Animais , Quimiocinas/metabolismo , Masculino , Camundongos , Metabolismo dos Lipídeos/fisiologia , Metabolismo dos Lipídeos/genética , Receptores Androgênicos/metabolismo , Receptores Androgênicos/genética , Glucose/metabolismo , Dieta Hiperlipídica , Diabetes Mellitus Experimental/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Condicionamento Físico Animal/fisiologia , Camundongos Endogâmicos C57BL , Mitocôndrias Musculares/metabolismo , Mitocôndrias/metabolismo , Androgênios/metabolismo , Androgênios/farmacologia , Músculo Esquelético/metabolismoRESUMO
Chemerin acts as both a chemotactic agent and an adipokine that undergoes proteolytic cleavage, converting inactive precursors into their active forms before being subsequently inactivated. Elevated chemerin levels are linked to obesity and type 2 diabetes mellitus (T2D). This study aimed to elucidate the effects of T2D and obesity on chemerin levels by comparing plasma samples from individuals with a normal weight and T2D (BMI < 25; NWD group n = 22) with those from individuals who are overweight or obese and have T2D (BMI ≥ 25; OWD group n = 39). The total chemerin levels were similar in the NWD and OWD groups, suggesting that T2D may equalize the chemerin levels irrespective of obesity status. The cleavage of chemerin has been previously linked to myocardial infarction and stroke in NWD, with potential implications for inflammation and mortality. OWD plasma exhibited lower levels of cleaved chemerin than the NWD group, suggesting less inflammation in the OWD group. Here, we showed that the interaction between obesity and T2D leads to an equalization in the total chemerin levels. The cleaved chemerin levels and the associated inflammatory state, however, differ significantly, underscoring the complex relationship between chemerin, T2D, and obesity.
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Chemerin is a chemokine/adipokine, regulating inflammation, adipogenesis and energy metabolism whose activity depends on successive proteolytic cleavages at its C-terminus. Chemerin levels and processing are correlated with insulin resistance. We hypothesized that chemerin processing would be higher in individuals with type 2 diabetes (T2D) and in those who are insulin resistant (IR). This hypothesis was tested by characterizing different chemerin forms by specific ELISA in the plasma of 18 participants with T2D and 116 without T2D who also had their insulin resistance measured by steady-state plasma glucose (SSPG) concentration during an insulin suppression test. This approach enabled us to analyze the association of chemerin levels with a direct measure of insulin resistance (SSPG concentration). Participants were divided into groups based on their degree of insulin resistance using SSPG concentration tertiles: insulin sensitive (IS, SSPG ≤ 91 mg/dL), intermediate IR (IM, SSPG 92-199 mg/dL), and IR (SSPG ≥ 200 mg/dL). Levels of different chemerin forms were highest in patients with T2D, second highest in individuals without T2D who were IR, and lowest in persons without T2D who were IM or IS. In the whole group, chemerin levels positively correlated with both degree of insulin resistance (SSPG concentration) and adiposity (BMI). Participants with T2D and those without T2D who were IR had the most proteolytic processing of chemerin, resulting in higher levels of both cleaved and degraded chemerin. This suggests that increased inflammation in individuals who have T2D or are IR causes more chemerin processing.
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The adipokines, visfatin, chemerin, and its receptor are expressed in the testis. It has also been shown that heat-stress alters the secretion and expression of other adipokines. Testicular heat-stress is now well known to cause the impairment in the testis. It has also been documented that heat-stress changes the expression of genes and proteins in the testis. To the best of our knowledge, the expression and localization of visfatin chemerin and its receptor have not been investigated in the heat-stressed testis. Therefore, the present study has investigated the expression and localization of these proteins in the heat-stressed testis. The expression of visfatin and chemerin and receptor exhibits a differential repossess against the heat stress. Visfatin expression was up-regulated while chemerin and chemerin receptor was down-regulated in the heat-stressed testis as shown by western blot analysis. The immunolocalization of visfatin and chemerin showed increased abundance in the seminiferous tubules of heat-stressed mice testis. Furthermore, abundance of visfatin, chemerin, and its receptor showed a decrease in abundance in the Leydig cells of heat-stressed testis. The decreased abundance of these proteins in the Leydig cells coincides with decreased 3ß-HSD immunostaining along with decreased testosterone levels. These results suggest that heat-stress might decrease testosterone secretion by modulating visfatin and chemerin in the Leydig cells. The increased abundance of visfatin and chemerin in the primary spermatocytes, round spermatid, and multinucleated germ cells also coincides with increased immunostaining of active caspase-3. Moreover, expression of Bcl-2 was down-regulated, and expression of active caspase-3 and HSP70 were up-regulated along with increased oxidative stress in the heat-stressed testis, suggesting stimulated apoptosis. In conclusion, our results showed that visfatin, chemerin, and its receptor are differentially expressed in the testis under heat-stress and within the testis also it might differentially regulate testosterone biosynthesis in the Leydig cells and apoptosis in the seminiferous tubules.
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Quimiocinas , Resposta ao Choque Térmico , Nicotinamida Fosforribosiltransferase , Receptores de Quimiocinas , Testículo , Masculino , Animais , Camundongos , Quimiocinas/metabolismo , Testículo/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Receptores de Quimiocinas/metabolismo , Receptores de Quimiocinas/genética , Células Intersticiais do Testículo/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Caspase 3/metabolismoRESUMO
We currently have a large sum of clinical and experimental data documenting the involvement of numerous adipokines in the maintenance of energy homeostasis in healthy individuals and their dysregulation in diseases such as obesity, metabolic syndrome or type 2 diabetes. Despite the impressive discoveries made in this field over many years, much remains to be done before understanding all the physiological and pathological implications, and hoping for the development of other effective and safe therapeutic strategies. Two original adipokines will be taken as examples to illustrate these remarks, chemerin and neuregulin 4.
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Adipocinas , Tecido Adiposo , Biomarcadores , Quimiocinas , Obesidade , Humanos , Adipocinas/metabolismo , Adipocinas/fisiologia , Tecido Adiposo/metabolismo , Obesidade/metabolismo , Biomarcadores/análise , Quimiocinas/metabolismo , Quimiocinas/fisiologia , Neurregulinas/metabolismo , Neurregulinas/fisiologia , Neurregulinas/genética , Diabetes Mellitus Tipo 2/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Animais , Síndrome Metabólica/metabolismoRESUMO
This study aims to investigate the effects of Gualou Xiebai Banxia Decoction(GXBD) on type 2 diabetes mellitus(T2DM) combined with acute myocardial infarction(AMI) in rats via chemerin/chemokine-like receptor 1(CMKLR1)/peroxisome proliferator-activated receptor α(PPARα) signaling pathway, and to explore the mechanism of GXBD in alleviating glucose and lipid metabolism disorders. The SD rats were randomized into control, model, positive control, and low-and high-dose GXBD groups. The rat model of T2DM was established by administration with high-fat emulsion(HFE) by gavage and intraperitoneal injection with streptozotocin, and then coronary artery ligation was performed to induce AMI. The control and model groups were administrated with the equal volume of normal saline, and other groups were administrated with corresponding drugs by gavage. Changes in relevant metabolic indicators were assessed by ELISA and biochemical assays, and the protein levels of chemerin, CMKLR1, and PPARα in the liver, abdominal fat, and heart were determined by Western blot. The results showed that GXBD alleviated the myocardial damage and reduced the levels of blood lipids, myocardial enzymes, and inflammatory cytokines, while it did not lead to significant changes in blood glucose. Compared with the model group, GXBD down-regulated the expression of chemerin in peripheral blood and up-regulated the expression of cyclic adenosine monophosphate(cAMP) and protein kinase A(PKA) in the liver. After treatment with GXBD, the protein levels of chemerin and CMKLR1 in the liver, abdominal fat, and heart were down-regulated, while the protein levels of PPARα in the liver and abdominal fat were up-regulated. In conclusion, GXBD significantly ameliorated the disorders of glycolipid metabolism in the T2DM-AMI model by regulating the chemerin/CMKLR1/PPARα signaling pathway to exert a protective effect on the damaged myocardium. This study provides a theoretical basis for further clinical study of GXBD against T2DM-AMI and is a manifestation of TCM treatment of phlegm and turbidity causing obstruction at the protein level.
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Diabetes Mellitus Tipo 2 , Medicamentos de Ervas Chinesas , Infarto do Miocárdio , Ratos , Animais , PPAR alfa/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ratos Sprague-Dawley , Transdução de Sinais , Infarto do Miocárdio/tratamento farmacológico , QuimiocinasRESUMO
Adipose tissue is an active endocrine gland, synthesizing and secreting multiple signaling molecules termed adipokines. Following the detection of adipokines and their receptors in the mammary tissue of various species, it is indicated that adipokines play a role in the development of the mammary gland. The aim of the present study was to determine the concentration-dependent influence of three adipokines, leptin, adiponectin, and chemerin, on the viability, apoptosis, and secretory activity of BME-UV1 bovine mammary epithelial cells. The study confirmed that BME-UV1 cells contain the leptin receptor (Ob-R) protein, and express transcripts of adiponectin (ADIPOR1 and ADIPOR2) and chemerin (CMLKR1 and GPR1) receptors. Regardless of the administered dose, none of the three tested adipokines had an effect on the viability of BME-UV1 cells, and the number of apoptotic cells remained unchanged. However, chemerin (100 ng/mL) stimulated BME-UV1 cells to synthesize and secrete αS1-casein, the major protein component of milk. These results indicate that chemerin may be a potent regulator of the bovine mammary epithelial cells' functional differentiation, contributing, along with the major systemic hormones and local growth factors, to the development of the bovine mammary gland.
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Apoptose , Quimiocinas , Células Epiteliais , Glândulas Mamárias Animais , Animais , Bovinos , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/citologia , Quimiocinas/metabolismo , Feminino , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular , Receptores de Adiponectina/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Caseínas/metabolismo , Adiponectina/metabolismoRESUMO
Recruitment and accumulation of reactive astrocytes around senile plaques are common pathological features of Alzheimer's disease (AD), with unclear mechanisms. Chemerin, an adipokine implicated in neuroinflammation, acts through its receptor, chemokine-like receptor 1 (CMKLR1), which also functions as a receptor for amyloid ß (Aß). The impact of the chemerin/CMKLR1 axis on astrocyte migration towards Aß plaques is unknown. Here we investigated the effect of CMKLR1 on astrocyte migration around Aß deposition in APP/PS1 mice with Cmklr1 knockout (APP/PS1-Cmklr1-/-). CMKLR1-expressed astrocytes were upregulated in the cortices and hippocampi of 9-month-old APP/PS1 mice. Chemerin mainly co-localized with neurons, and its expression was reduced in the brains of APP/PS1 mice, compared to WT mice. CMKLR1 deficiency decreased astrocyte colocalization with Aß plaques in APP/PS1-Cmklr1-/- mice, compared to APP/PS1 mice. Activation of the chemerin/CMKLR1 axis promoted the migration of primary cultured astrocytes and U251 cells, and reduced astrocyte clustering induced by Aß42. Mechanistic studies revealed that chemerin/CMKLR1 activation induced STING phosphorylation. Deletion of STING attenuated the promotion of the chemerin/CMKLR1 axis relative to astrocyte migration and abolished the inhibitory effect of chemerin on Aß42-induced astrocyte clustering. These findings suggest the involvement of the chemerin/CMKLR1/STING pathway in the regulation of astrocyte migration and recruitment to Aß plaques/Aß42.
Assuntos
Doença de Alzheimer , Astrócitos , Quimiocinas , Peptídeos e Proteínas de Sinalização Intercelular , Placa Amiloide , Receptores de Quimiocinas , Animais , Astrócitos/metabolismo , Quimiocinas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Receptores de Quimiocinas/metabolismo , Receptores de Quimiocinas/genética , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Humanos , Peptídeos beta-Amiloides/metabolismo , Camundongos Knockout , Movimento Celular , Transdução de Sinais , Camundongos Transgênicos , Camundongos Endogâmicos C57BLRESUMO
We executed this study to determine if chemerin-like receptor 1 (CMKLR1), a Gi/o protein-coupled receptor expressed by leukocytes and non-leukocytes, contributes to the development of phenotypic features of non-atopic asthma, including airway hyperresponsiveness (AHR) to acetyl-ß-methylcholine chloride, lung hyperpermeability, airway epithelial cell desquamation, and lung inflammation. Accordingly, we quantified sequelae of non-atopic asthma in wild-type mice and mice incapable of expressing CMKLR1 (CMKLR1-deficient mice) following cessation of acute inhalation exposure to either filtered room air (air) or ozone (O3), a criteria pollutant and non-atopic asthma stimulus. Following exposure to air, lung elastic recoil and airway responsiveness were greater while the quantity of adiponectin, a multi-functional adipocytokine, in bronchoalveolar lavage (BAL) fluid was lower in CMKLR1-deficient as compared to wild-type mice. Regardless of genotype, exposure to O3 caused AHR, lung hyperpermeability, airway epithelial cell desquamation, and lung inflammation. Nevertheless, except for minimal genotype-related effects on lung hyperpermeability and BAL adiponectin, we observed no other genotype-related differences following O3 exposure. In summary, we demonstrate that CMKLR1 limits the severity of innate airway responsiveness and lung elastic recoil but has a nominal effect on lung pathophysiology induced by acute exposure to O3.
Assuntos
Asma , Ozônio , Pneumonia , Animais , Camundongos , Masculino , Ozônio/efeitos adversos , Adiponectina/farmacologia , Pulmão , Pneumonia/induzido quimicamente , Líquido da Lavagem Broncoalveolar , Receptores Acoplados a Proteínas G , Asma/genética , Quimiocinas/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologiaRESUMO
The prevalence of osteoporosis has been on the rise globally. With ageing populations, research has sought therapeutic solutions in novel areas. One such area is that of the adipokines. Current literature points to an important role for these chemical mediators in relation to bone metabolism. Well-established adipokines have been broadly reported upon. These include adiponectin and leptin. However, other novel adipokines such as visfatin, nesfatin-1, meteorin-like protein (Metrnl), apelin and lipocalin-2 are starting to be addressed pre-clinically and clinically. Adipokines hold pro-inflammatory and anti-inflammatory properties that influence the pathophysiology of various bone diseases. Omentin-1 and vaspin, two novel adipokines, share cardioprotective effects and play essential roles in bone metabolism. Studies have reported bone-protective effects of omentin-1, whilst others report negative associations between omentin-1 and bone mineral density. Lipocalin-2 is linked to poor bone microarchitecture in mice and is even suggested to mediate osteoporosis development from prolonged disuse. Nesfatin-1, an anorexigenic adipokine, has been known to preserve bone density. Animal studies have demonstrated that nesfatin-1 treatment limits bone loss and increases bone strength, suggesting exogenous use as a potential treatment for osteopenic disorders. Pre-clinical studies have shown adipokine apelin to have a role in bone metabolism, mediated by the enhancement of osteoblast genesis and the inhibition of programmed cell death. Although many investigations have reported conflicting findings, sufficient literature supports the notion that adipokines have a significant influence on the metabolism of bone. This review aims at highlighting the role of novel adipokines in osteoporosis while also discussing their potential for treating osteoporosis.