The aim of the studies was to ascertain if adenosine is able to co-operate with selected hematopoietic growth factors and cytokines, namely with granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), stem cell factor (SCF), interleukin-3 (IL-3), and interleukin-11 (IL-11), in inducing the growth of colonies from hematopoietic progenitor cells for granulocytes and macrophages (GM-CFC) from normal bone marrow cells in vitro. Adenosine was found not to produce any colonies when present in the cultures as the only potential stimulator. All the tested cytokines and growth factors were observed to induce the growth of distinct numbers of GM-CFC colonies, with the exception of IL-11. When suboptimal concentrations of the evaluated cytokines and growth factors were tested in the cultures in which various concentrations of adenosine were concomitantly present, mutually potentiating effects were found in the case of IL-3 and SCF. These results confirm the role of adenosine in regulation of granulopoiesis and predict IL-3 and SCF as candidates for further in vivo studies of their combined administration with adenosine.
Erythrocytes (RBC) from untrained male Wistar rats and rat glomerular endothelial cells (EC) were used to investigate the effects of acute exercise (speed: 20 m/min, slope: 0, duration: 1 hour) on RBC membrane protein oxidation and adhesion to cultured EC. Experimental animals were divided into juvenile (age 10 weeks) and adult (age 30 weeks) groups for these studies. Immediately following exercise, juvenile rat RBC membrane protein oxidation was significantly enhanced. Adult rat RBC showed significantly higher basal protein oxidation than juvenile RBC; but the level of adult rat RBC membrane protein oxidation was unaffected by exercise. Prior to exercise, adult rat RBC showed significantly higher adhesion to EC than RBC of juvenile rat. There was no difference in plasma fibronectin or fibrinogen levels following exercise. Only juvenile rat RBC showed a significant decrease in sialic acid residue content following exercise. These experiments show that there are changes in RBC-EC interactions following exercise that are influenced by animal age.
This review briefly outlines the history and possibilities of bone reconstruction using various types of artificial materials, which allow interaction with cells only on the surface of the implant or enable ingrowth of cells inside the material. Information is also provided on the most important properties of bone cells taking part in bone tissue development, and on diseases and regeneration. The most common cell types used for testing cell-material interaction in vitro are listed, and the most commonly used approaches to this testing are also mentioned. A considerable part of this review is dedicated to the physical and chemical properties of the materi al surface, which are decisive for the cell-material interaction, and also to modifications to the surface of the material aimed at integrating it better with the surrounding bone tissue. Special attention is paid to the effects of nanoscale and microscale surface roughness on cell behaviour, to material surface patterning, which allows regionally-selective adhesion and growth of cells, an d also to the surface chemistry. In addition, coating the materials with bioactive layers is examined, particularly those create d by deposition of fullerenes, hybrid metal-fullerene composites, carbon nanotubes, nanocrystalline diamond films, diamond-like carbon, and nanocomposite hydrocarbon plasma polymer films enriched with metals., M. Vandrovcová, L. Bačáková., and Obsahuje bibliografii a bibliografické odkazy
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.
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