Heroin addiction markedly affects the nutritional and metabolic status and frequently leads to malnutrition. The aim of our study was to compare circulating concentration of adipose tissue-derived hormones leptin, adiponectin and resistin in 12 patients with heroin addiction before and after one-year methadone maintenance treatment with the group of 20 age- and body mass index-matched healthy subjects. Basal serum leptin and adiponectin levels in heroin addicts were significantly decreased (3.4±
0.4 vs. 4.5±0.6 ng/ml and 18.9±3.3 vs. 33.9±3.1 ng/μl, respectively; p<0.05) while serum resistin concentrations were increased compared to healthy subjects (10.1±1.2 vs. 4.6±0.3 ng/ml; p<0.05). Moreover, positive correlation of serum leptin levels with body mass index was lost in the addicts in contrast to control group. One year of methadone maintenance treatment normalized serum leptin, but not serum adiponectin and resistin concentrations. In conclusion, circulating concentrations of leptin, adiponectin and resistin are markedly altered in patients with chronic heroin addiction. These alterations appear to be relatively independent of nutritional status and insulin sensitivity.
Adipose tissue-produced hormones significantly affect the metabolism of lipids and carbohydrates as well as numerous other processes in human body. It is generally accepted that endocrine dysfunction of adipose tissue may represent one of the causal links between obesity and insulin resistance/diabetes. Epidemiological studies underlined that obesity represents a significant risk factor for the development of cancer, although the exact mechanism of this relationship remains to be determined. Multiple recent studies have indicated that some of adipose tissue-derived hormones may significantly influence the growth and proliferation of tumorous stroma and malignant cells within. Here we review current knowledge about possible relationship of leptin and adiponectin to the etiopathogenesis of different malignant tumors. Most of the studies indicated that while leptin may potentiate the growth of cancer cells in vitro, adiponectin appears to have an opposite effect. Further studies are necessary to decide whether obesity-induced endocrine dysfunction of adipose tissue can directly influence carcinogenesis in different tissues and organs.
Cíl studie: Prozkoumat vztahy zavedených a zvažovaných prediktorů přežití u hemodialyzovaných pacientů a zjistit jejich spojitost s přítomností metabolického syndromu (MS). Typ studie: Observační průřezová studie. Název a sídlo pracoviště: Ústav klinické biochemie a hematologie, Univerzita Karlova v Praze, Lékařská fakulta v Plzni a Fakultní nemocnice Plzeň. Materiál a metoda: 80 hemodialyzovaných pacientů (věk 67,0 [61,0–73,5] let, BMI 27,5 [22,7–33,0] kg/m2; medián [mezikvartilové rozpětí], 37 žen) bylo rozděleno do 2 skupin podle defi nice MS (NCEP ATP III) (39 pacientů s MS). Vylučovací kritérium: CRP > 30 mg/l. Vzorky séra a plazmy byly odebírány těsně před zahájením hemodialýzy. Sledovány byly následující parametry: adiponektin (včetně vysokomolekulární formy), leptin, TNF-alfa, PAI-1, ADMA, inzulin, CRP, albumin. K hodnocení rozdílů mezi skupinami byl použit Wilcoxonův dvouvýběrový test. Výsledky: U adiponektinu a leptinu byly nalezeny rozdíly mezi pohlavími v rámci skupin. Koncentrace adiponektinu a podíl jeho vysokomolekulární (HMW) formy byly vyšší u žen ve skupině bez MS (95% CI pro rozdíl mediánů 0,45–10,33 mg/l, respektive 0,006–0,10, p < 0,05), ale mezi pohlavími u pacientů s MS se významně nelišily. Na druhou stranu, hladiny leptinu byly vyšší u žen pouze ve skupině s MS (CI 7,30–52,80 μg/l, p < 0,05). U pacientů s MS byly u obou pohlaví pozorovány nižší hladiny adiponektinu (CI 2,57–8,78 mg/l pro muže a 5,90–14,94 mg/l pro ženy, p < 0,001), nižší podíl HMW formy (CI 0,02–0,13 pro muže a 0,10–0,21 pro ženy, p < 0,001), vyšší hladiny leptinu (CI 11,50–48,10 μg/l pro muže a 31,60–78,40 μg/l pro ženy, p < 0,001) a vyšší hladiny inzulinu (CI 5,4–14,5 mIU/l, p < 0,001). U následujících parametrů nebyly zjištěny statisticky významné rozdíly mezi skupinami: ADMA (CI -0,32–0,13 μmol/l, p = 0,45), CRP (CI -1,55–3,05 mg/l, p = 0,59), PAI-1 (CI -0,7–6,3 μg/l, p = 0,16), TNF-alfa (CI -0,46–0,12 ng/l, p = 0,28) a albumin (CI -2,1–0,8 g/l, p = 0,41). Závěr: Koncentrace adiponektinu a leptinu odrážely přítomnost MS, hladiny zavedených prediktorů přežití, CRP a albuminu, se ale překvapivě mezi skupinami nelišily. Tyto výsledky by nasvědčovaly omezenému významu MS v prognóze hemodialyzovaných pacientů., Objective: To explore the relationships of established or putative survival predictors in hemodialysis patients and their connection with the presence of the metabolic syndrome (MS). Design: Observational, cross-sectional. Settings: Department of Clinical Biochemistry and Hematology, Faculty Hospital and Charles University – Faculty of Medicine in Pilsen, Czech Republic. Material and methods: 80 hemodialyzed patients (median [IQR] of age = 67.0 [61.0–73.5] years, BMI = 27.5 [22.7–33.0] kg/m2, 37 females) were divided into 2 groups according to NCEP ATP III defi nition of the MS (39 patients with MS). Exclusion criterion: CRP level > 30 mg/l. Serum and plasma samples were taken prior to hemodialysis initiation. Following parameters were examined: adiponectin (including high-molecular weight form), leptin, TNF-alpha, PAI-1, ADMA, insulin, CRP, albumin. Comparison between groups was done using Wilcoxon rank-sum test for independent samples. Results: Gender differences have been found in adiponectin and leptin levels within the groups. Adiponectin levels and the portion of its high-molecular weight (HMW) form were higher in females in the group without MS (95% CI for the difference of medians 0.45–10.33 mg/l and 0.006-0.10, p < 0.05), respectively, but were not different between sexes in the patients with MS. On the other hand, leptin levels were different (higher in females) only in the group with MS (CI 7.30–52.80 μg/l, p < 0.05). Both for males (M) and females (F), the group with MS showed lower adiponectin levels (CI 2.57–8.78 mg/l for M and 5.90–14.94 mg/l for F, p < 0.001), lower portion of HMW-adiponectin (CI 0.02–0.13 for M and 0.10–0.21 for F, p < 0.001), higher levels of leptin (CI 11.50–48.10 μg/l for M and 31.60–78.40 μg/l for F, p < 0.001) and higher levels of insulin (CI 5.4–14.5 mIU/l, p < 0,001). No statistically signifi cant differences were found in ADMA (CI 0.32–0.13 μmol/l, p = 0.45), CRP (CI 1.55–3.05 mg/l, p = 0.59), PAI-1 (CI 0.7–6.3 μg/l, p = 0.16), TNF-alpha (CI 0.46–0.12 ng/l, p = 0.28) and albumin levels (CI 2.1–0.8, p = 0.41). Conclusion: The concentration of adiponectin and leptin well refl ected the presence of the metabolic syndrome. Surprisingly, levels of conventional survival predictors (CRP, albumin) did not vary between the groups. These fi ndings may suggest a limited relevance of the MS concept in the prognosis of HD patients., Vostrý Michal, Rajdl D., Eiselt J., Malánová L., Pikner R., Trefil L., Racek J., and Lit.: 18
It is now generally accepted that adipose tissue acts as an endocrine organ producing a number of substances with an important role in the regulation of food intake, energy expenditure and a series of metabolic processes. Adiponectin is a recently discovered protein produced exclusively by adipocytes. A number of studies have shown that obesity, insulin resistance and atherosclerosis are accompanied by decreased adiponectin levels and that adiponectin replacement under experimental settings is able to diminish both insulin resistance and atherosclerosis. The aim of this review is to summarize the current knowledge about the physiology and pathophysiology of adiponectin and to discuss its potential in the treatment of insulin resistance and atherosclerosis.
Genes for adiponectin and resistin are candidate genes of insulin resistance and type 2 diabetes mellitus. The aim of our study was to determine the frequency of single nucleotide polymorphisms (SNP) 45T>G and 276G>T of the adiponectin gene and 62G>A and -180C>G of the resistin gene in patients with obesity (OB), anorexia nervosa (AN) and in control healthy normal-weight women (NW) and to study the influence of particular genotypes on serum concentrations of these hormones and on insulin sensitivity. Serum adiponectin, resistin, tumor necrosis factor alpha (TNF-alpha), insulin, cholesterol, glycated hemoglobin (HbA1c) and blood glucose levels were measured in 77 patients with OB, 28 with AN and 38 NW. DNA analysis was carried out by polymerase chain reaction with restriction analysis of PCR product. The presence of SNP ADP+276 G>T allele was accompanied by higher cholesterol levels in AN patients, higher adiponectin concentrations in OB patients and lower HbA1c levels in NW. SNP of the resistin gene 62G>A was associated with lower HbA1c in NW and higher cholesterol concentrations in OB group. The carriers of the minor G allele in the position -180 of the resistin gene within AN group had significantly higher BMI relative to non-carriers. We conclude that polymorphisms in adiponectin and resistin genes can contribute to metabolic phenotype of patients with obesity and anorexia nervosa., J. Křížová, M. Dolinková, Z. Lacinová, Š. Sulek, R. Doležalová, J. Housová, J. Krajíčková, D. Haluzíková, L. Bošanská, H. Papežová, M. Haluzík., and Obsahuje bibliografii a bibliografické odkazy
Serum levels of adiponectin were measured in patients with benign prostatic hyperplasia and prostate cancer of pT2 and pT3 stage. Adiponectin ELISA assay, immunohistochemistry, and selected metabolic and biochemical parameters measurement was performed in 25 patients with benign prostatic hyperplasia and 43 with prostate cancer (17 patients with organ-confined and 26 patients with locally advanced disease). Serum adiponectin levels did not differ between prostate benign hyperplasia and cancer clinical stage T2, but was significantly higher in pT3 relative to pT2 group (14.51± 4.92 vs. 21.41±8. 12, P = 0.003). Tissue immunohistochemistry showed enhanced staining in neoplastic prostate glands and intraepithelial neoplasia relative to benign prostatic hyperplasia without distinction between disease grade and stage. Serum adiponectin levels are higher in locally advanced relative to organ-confined prostate cancer and may thus serve as an auxiliary marker providing further improvement for discrimination between pT2 and pT3 stages., D. Housa, Z. Vernerová, J. Heráček, B. Procházka, P. Čechák, J. Kuncová, M. Haluzík., and Obsahuje bibliografii a bibliografické odkazy
Adiponectin (APN), an adipose tissue-excreted adipokine, plays protective roles in metabolic and cardiovascular diseases. In this study, the effects and mechanisms of APN on biological functions of rat vascular endothelial progenitor cells (VEPCs) were investigated in vitro . After administrating APN in rat VEPCs, the proliferation was measured by methyl thiazolyl tetrazolium (MTT) method, the apoptotic rate was test by Flow cytometry assay, mRNA expression of B-cell lymphoma-2 (Bcl-2) and vascular endothelial growth factor (VEGF) was determined by real-time reverse transcriptase polymerase chain reaction (RT-PCR), and protein expression of mechanistic target of rapamycin (mTOR), signal transducer and activator of transcription 3 (STAT3) and phospho-STAT3 (pSTAT3) was analyzed by Western blot. It was suggested that APN promoted the optical density (OD) value of VEPCs, enhanced mRNA expression of Bcl-2 and VEGF, and inhibited cell apoptotic rate. Furthermore, protein expression of pSTAT3 was also increased in the presence of APN. Moreover, APN changed-proliferation, apoptosis and VEGF expression of VEPCs were partially suppressed after blocking the mTOR-STAT3 signaling pathway by the mTOR inhibitor XL388. It was indicated that APN promoted biological functions of VEPCs through targeting the mTOR-STAT3 signaling pathway., Xiaoying Dong, Xia Yan, Wei Zhang, Shengqiu Tang., and Obsahuje bibliografii
Adiponectin acts as an endogenous antithrombotic factor. However, the mechanisms underlying the inhibition of platelet aggregation by adiponectin still remain elusive. The present study was designed to test whether adiponectin inhibits platelet aggregation by attenuation of oxidative/nitrative stress. Adult rats were fed a regular or high-fat diet for 14 weeks. The platelet was immediately separated and stimulated with recombinant full-length adiponectin (rAPN) or not. The platelet aggregation, nitric oxide (NO) and superoxide production, endothelial nitric oxide synthase (eNOS)/inducible NOS (iNOS) expression, and antioxidant capacity were determined. Treatment with rAPN inhibited hyperlipidemia- induced platelet aggregation (P<0.05). Interestingly, total NO, a crucial molecule depressing platelet aggregation and thrombus formation , was significantly reduced, rather than increased in rAPN-treated platelets. Treatment with rAPN markedly decreased superoxide production (-62 %, P<0.05) and enhanced antioxidant capacity (+38 %, P<0.05) in hyperlipidemic platelets. Hyperlipidemia-induced reduced eNOS phosphorylation and increased iNOS expression were significantly reversed following rAPN treatment (P<0.05, P<0.01, respectively). Taken together, these data suggest that adiponectin is an adipokine that suppresses platelet aggregation by enhancing eNOS activation and attenuating oxidative/nitrative stress including blocking iNOS expression and superoxide production., W.-Q. Wang ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Adiponectin is an adipokine increasing glucose and fatty acid metabolism and improving insulin sensitivity. The aim of this study was to investigate the role of adiponectin in the regulation of adipocyte lipolysis. Human adipocytes isolated from biopsies obtained during surgical operations from 16 non-obese and 17 obese subjects were incubated with 1) human adiponectin (20 μg/ml) or 2) 0.5 mM AICAR - activator of AMPK (adenosine monophosphate activated protein kinase). Following these incubations, isoprenaline was added (10-6 M) to investigate the influence of adiponectin and AICAR on catecholamine-induced lipolysis. Glycerol concentration was measured as lipolysis marker. We observed that adiponectin suppressed spontaneous lipolysis by 21 % and isoprenaline-induced lipolysis by 14 % in non-obese subjects. These effects were not detectable in obese individuals, but statistically significant differences in the effect of adiponectin between ob ese and non-obese were not revealed by two way ANOVA test. The inhibitory effect of AICAR and adiponectin on lipolysis was reversed by Compound C. Our results suggest, that adiponectin in physiological concentrations inhibits spontaneous as well as catecholamine-induced lipolysis. This effect might be lower in obese individuals and this regulation seems to involve AMPK., Z. Wedellová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Adipose tissue is a hormonally active tissue, producing adipocytokines which may influence activity of other tissues. Adiponectin, abundantly present in the plasma increases insulin sensitivity by stimulating fatty acid oxidation, decreases plasma triglycerides and improves glucose metabolism. Adiponectin levels are inversely related to the degree of adiposity. Anorexia nervosa and type 1 diabetes are associated with increased plasma adiponectin levels and higher insulin sensitivity. Decreased plasma adiponectin levels were reported in insulin-resistant states, such as obesity and type 2 diabetes and in patients with coronary artery disease.Activity of adiponectin is associated with leptin, resistin and with steroid and thyroid hormones, glucocorticoids, NO and others.
Adiponectin suppresses expression of extracellular matrix adhesive proteins in endothelial cells and atherosclerosis potentiating cytokines. Anti-atherogenic and anti-inflammatory properties of adiponectin and the ability to stimulate insulin sensitivity have made adiponectin an important object for physiological and pathophysiological studies with the aim of potential therapeutic applications.