OBJECTIVE: GDF11 is a member of the TGF-β superfamily that was recently implicated as potential "rejuvenating" factor, which can ameliorate metabolic disorders. The main objective of the presented study was to closely characterize the role of GDF11 signaling in the glucose homeostasis and in the differentiation of white adipose tissue. METHODS: We performed microscopy imaging, biochemical and transcriptomic analyses of adipose tissues of 9 weeks old ob/ob mice and murine and human pre-adipocyte cell lines. RESULTS: Our in vivo experiments employing GDF11 treatment in ob/ob mice showed improved glucose/insulin homeostasis, decreased weight gain and white adipocyte size. Furthermore, GDF11 treatment inhibited adipogenesis in pre-adipocytes by ALK5-SMAD2/3 activation in cooperation with the WNT/β-catenin pathway, whose inhibition resulted in adipogenic differentiation. Lastly, we observed significantly elevated levels of the adipokine hormone adiponectin and increased glucose uptake by mature adipocytes upon GDF11 exposure. CONCLUSION: We show evidence that link GDF11 to adipogenic differentiation, glucose, and insulin homeostasis, which are pointing towards potential beneficial effects of GDF11-based "anti-obesity" therapy.

• MeSH
• adipogeneze * MeSH
• adiponektin metabolismus   MeSH
• beta-katenin * metabolismus   MeSH
• buněčná diferenciace fyziologie   MeSH
• glukosa metabolismus   MeSH
• inzulin metabolismus   MeSH
• kostní morfogenetické proteiny metabolismus   MeSH
• lidé MeSH
• myši MeSH
• protein Smad2 MeSH
• protein Smad3 MeSH
• receptory regulované proteiny Smad MeSH
• růstové diferenciační faktory metabolismus   MeSH
• signální dráha Wnt MeSH
• TGF-beta receptor I. typu MeSH
• transformující růstový faktor beta metabolismus   MeSH
• tukové buňky metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

OBJECTIVES: Chemotherapeutic drugs induce senescence in cancer cells but, unlike replicative senescence or oncogene-induced senescence, do so rather inefficiently and depending on DNA damage. A thorough understanding of the biology of chemotherapy-induced senescent cells requires their isolation from a mixed population of adjacent senescent and non-senescent cancer cells. MATERIALS AND METHODS: We have developed and optimized a rapid iodixanol (OptiPrep)-based gradient centrifugation system to identify, isolate and characterize doxorubicin (DXR)-induced senescent hepatocellular carcinoma (HCC) cells (HepG2 and Huh-7) in vitro. RESULTS: After cellular exposure to DXR, we used iodixanol gradient-based centrifugation to isolate and re-plate cells on collagen-coated flasks, despite their low or null proliferative capacity. The isolated cell populations were enriched for DXR-induced senescent HCC cells, as confirmed by proliferation arrest assay, and β-galactosidase and DNA damage-dependent γH2A.X staining. CONCLUSIONS: Analysing pure cultures of chemotherapy-induced senescent versus non-responsive cancer cells will increase our knowledge on chemotherapeutic mechanisms of action, and help refine current therapeutic strategies.

• MeSH
• doxorubicin farmakologie   MeSH
• hepatocelulární karcinom patologie   MeSH
• kyseliny trijodbenzoové farmakologie   MeSH
• lidé MeSH
• nádory jater patologie   MeSH
• poškození DNA účinky léků   MeSH
• separace buněk * metody   MeSH
• stárnutí buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

OBJECTIVES: Bioactive peptides derived from receptor binding motifs of native proteins are a potent source of bioactive molecules that can induce signalling pathways. These peptides could substitute for osteogenesis promoting supplements. The work presented here compares three kinds of bioactive peptides derived from collagen III, bone morphogenetic protein 7 (BMP-7) and BMP-2 with their potential osteogenic activity on the model of porcine mesenchymal stem cells (pMSCs). MATERIALS AND METHODS: pMSCs were cultured on electrospun polycaprolactone nanofibrous scaffolds with different concentrations of the bioactive peptides without addition of any osteogenic supplement. Analysis of pMSCs cultures included measurement of the metabolic activity and proliferation, immunofluorescence staining and also qPCR. RESULTS: Results showed no detrimental effect of the bioactive peptides to cultured pMSCs. Based on qPCR analysis, the bioactive peptides are specific for osteogenic differentiation with no detectable expression of collagen II. Our results further indicate that peptide derived from BMP-2 protein promoted the expression of mRNA for osteocalcin (OCN) and collagen I significantly compared to control groups and also supported deposition of OCN as observed by immunostaining method. CONCLUSION: The data suggest that bioactive peptide with an amino acid sequence of KIPKASSVPTELSAISTLYL derived from BMP-2 protein was the most potent for triggering osteogenic differentiation of pMSCs.

• MeSH
• buněčná diferenciace účinky léků   MeSH
• buněčné kultury MeSH
• kolagen typ II genetika   metabolismus   MeSH
• kolagen typu I genetika   metabolismus   MeSH
• konfokální mikroskopie MeSH
• kultivované buňky MeSH
• mezenchymální kmenové buňky cytologie   účinky léků   metabolismus   MeSH
• mikroskopie elektronová rastrovací MeSH
• miniaturní prasata MeSH
• osteogeneze účinky léků   MeSH
• osteokalcin genetika   metabolismus   MeSH
• peptidy chemie   farmakologie   MeSH
• prasata MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

OBJECTIVES: Faulty wound healing is a global healthcare problem. Chronic wounds are generally characterized by a reduction in availability of growth factors. New strategies are being developed to deliver growth factors more effectively. METHODS: In this study, we introduced electrospun scaffolds composed of polycaprolactone (PCL) nanofibers functionalized with adhered platelets, as a source of numerous growth factors. Three concentrations of platelets were immobilized to nanofibrous scaffolds by simple adhesion, and their influence on adhesion, proliferation and metabolic activity of seeded cells (murine fibroblasts, keratinocytes and melanocytes) was investigated. RESULTS: The data obtained indicated that presence of platelets significantly promoted cell spreading, proliferation and metabolic activity in all the skin-associated cell types. There were no significant differences among tested concentrations of platelets, thus even the lowest concentration sufficiently promoted proliferation of the seeded cells. CONCLUSIONS: Such complex stimulation is needed for improved healing of chronic wounds. However, the nanofibrous system can be used not only as a skin cover, but also in broader applications in regenerative medicine.

• MeSH
• buněčná adheze MeSH
• buněčné linie MeSH
• fibroblasty cytologie   metabolismus   MeSH
• hojení ran MeSH
• keratinocyty cytologie   metabolismus   MeSH
• melanocyty cytologie   metabolismus   MeSH
• myši MeSH
• nanovlákna chemie   ultrastruktura   MeSH
• polyestery chemie   MeSH
• proliferace buněk * MeSH
• tkáňové inženýrství MeSH
• tkáňové podpůrné struktury chemie   MeSH
• trombocyty cytologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

OBJECTIVES: Therapeutic potential of conventionally used platinum-based drugs in treatment of colorectal tumours has been limited due to high incidence of tumour resistance to them and to their severe side effects. This evokes a search for more suitable anti-cancer drugs. We have compared ability of oxaliplatin and a novel platinum(IV) complex, LA-12, to modulate the cell cycle and induce apoptosis in human colon adenocarcinoma HCT116 wt and p53/p21 null cells, and have investigated molecular mechanisms involved. MATERIALS AND METHODS: Cell cycle-related changes were analysed by flow cytometry (bromodeoxyuridine/propidium iodide staining, histone H3 phosphorylation). Apoptosis was detected using flow cytometry (assays monitoring caspase activity) and fluorescence microscopy (nuclear morphology). Changes in levels of genes/proteins involved in cell cycle and apoptosis regulation were examined by RT-PCR and western blotting. RESULTS: Our results highlight the outstanding ability of LA-12 to induce effective elimination of colon cancer cells independently of p53/p21, and in significantly lower doses compared to oxaliplatin. While oxaliplatin induced p53- and p21-dependent G2 -phase arrest associated with downregulation of cyclin B1 and Cdk1, LA-12 allowed cells to enter M-phase of the cell cycle regardless of p53/p21 status. CONCLUSIONS: Higher malignant cell toxicity and ability to bypass cell cycle arrest important for the cell damage repair suggest LA-12 to be a more effective candidate for elimination of colon tumours from a variety of genetic backgrounds, compared with oxaliplatin.

• MeSH
• adenokarcinom farmakoterapie   genetika   MeSH
• amantadin analogy a deriváty   farmakologie   MeSH
• antitumorózní látky farmakologie   MeSH
• apoptóza účinky léků   genetika   MeSH
• buněčné dělení účinky léků   genetika   MeSH
• cyklin B1 genetika   MeSH
• HCT116 buňky MeSH
• inhibitor p21 cyklin-dependentní kinasy genetika   MeSH
• lidé MeSH
• mitóza účinky léků   genetika   MeSH
• nádorové buněčné linie MeSH
• nádorový supresorový protein p53 genetika   MeSH
• nádory tračníku farmakoterapie   genetika   MeSH
• organoplatinové sloučeniny farmakologie   MeSH
• proliferace buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVES: We prepared 3D poly (ε-caprolactone) (PCL) nanofibre scaffolds and tested their use for seeding, proliferation, differentiation and migration of mesenchymal stem cell (MSCs). MATERIALS AND METHODS: 3D nanofibres were prepared using a special collector for common electrospinning; simultaneously, a 2D PCL nanofibre layer was prepared using a classic plain collector. Both scaffolds were seeded with MSCs and biologically tested. MSC adhesion, migration, proliferation and osteogenic differentiation were investigated. RESULTS: The 3D PCL scaffold was characterized by having better biomechanical properties, namely greater elasticity and resistance against stress and strain, thus this scaffold will be able to find broad applications in tissue engineering. Clearly, while nanofibre layers of the 2D scaffold prevented MSCs from migrating through the conformation, cells infiltrated freely through the 3D scaffold. MSC adhesion to the 3D nanofibre PCL layer was also statistically more common than to the 2D scaffold (P < 0.05), and proliferation and viability of MSCs 2 or 3 weeks post-seeding, were also greater on the 3D scaffold. In addition, the 3D PCL scaffold was also characterized by displaying enhanced MSC osteogenic differentiation. CONCLUSIONS: We draw the conclusion that all positive effects observed using the 3D PCL nanofibre scaffold are related to the larger fibre surface area available to the cells. Thus, the proposed 3D structure of the nanofibre layer will find a wide array of applications in tissue engineering and regenerative medicine.

• MeSH
• buněčná diferenciace * MeSH
• buněčné kultury přístrojové vybavení   metody   MeSH
• kultivované buňky MeSH
• lidé MeSH
• mezenchymální kmenové buňky cytologie   metabolismus   MeSH
• nanovlákna chemie   ultrastruktura   MeSH
• osteogeneze MeSH
• osteokalcin metabolismus   MeSH
• pohyb buněk MeSH
• polyestery chemie   MeSH
• povrchové vlastnosti MeSH
• proliferace buněk MeSH
• pružnost MeSH
• regenerativní lékařství MeSH
• sialoprotein vázající integrin metabolismus   MeSH
• tkáňové inženýrství MeSH
• tkáňové podpůrné struktury * MeSH
• viabilita buněk MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVES: The aim of this study was to develop functionalized nanofibres as a simple delivery system for growth factors (GFs) and make nanofibre cell-seeded scaffold implants a one-step intervention. MATERIALS AND METHODS: We have functionalized polycaprolactone (PCL) nanofibres with thrombocytes adherent on them. Immobilized, these thrombocytes attached to nanofibre scaffolds were used as a nanoscale delivery system for native (autologous) proliferation and differentiation factors, in vitro. Pig chondrocytes were seeded on the thrombocyte-coated scaffolds and levels of proliferation and differentiation of these cells were compared with those seeded on non-coated scaffolds. RESULTS: Immobilized thrombocytes on PCL nanofibres effectively enhanced chondrocyte proliferation due to time-dependent degradation of thrombocytes and release of their GFs. CONCLUSIONS: These simply functionalized scaffolds present new possibilities for nanofibre applications, as smart cell scaffolds equipped with a GF delivery tool.

• MeSH
• buněčná diferenciace MeSH
• chondrocyty cytologie   MeSH
• imobilizované buňky metabolismus   MeSH
• kultivované buňky MeSH
• mezibuněčné signální peptidy a proteiny aplikace a dávkování   MeSH
• nanovlákna chemie   MeSH
• nosiče léků chemie   MeSH
• polyestery chemie   MeSH
• prasata MeSH
• proliferace buněk MeSH
• trombocyty cytologie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVES: This study was performed to explore the strategy of combining Chk1 inhibitors with ionizing radiation (IR) to selectively target p53-deficient cancer cells. MATERIALS AND METHODS: Survival and cell cycle progression were measured in response to IR and the Chk1 inhibitors, UCN-01 and CEP-3891, in colon carcinoma HCT116 p53+/+ and p53-/- cells, and in osteosarcoma U2OS-VP16 cells with conditional expression of dominant-negative p53 (p53DD). RESULTS: Clonogenic survival was selectively reduced in HCT116 p53-/- compared to p53+/+ cells after treatment with UCN-01 and IR, and HCT116 p53+/+ cells also displayed strong p53-dependent G(1) arrest in the 1st cell cycle after IR. In contrast, clonogenic survival was affected similarly in U2OS-VP16 cells with and without expression of p53DD. However, death of U2OS-VP16 cells was p53 dependent as assessed by cell viability assay at 72 h, and this was associated with p53-dependent G(1) arrest in the 2nd cell cycle after treatment. Notably, HCT116 cells were overall more resistant than U2OS cells to cytotoxic effects of Chk1 inhibitors. CONCLUSION: Our results suggest that p53-dependent G(1) arrest in both 1st and 2nd cell cycles may protect human cancer cells from cell death after treatment with IR and Chk1 inhibitors. However, a challenge for future clinical use will be that different cancers display different intrinsic sensitivity to such inhibitors.

• MeSH
• buněčná smrt účinky léků   genetika   MeSH
• buněčný cyklus * účinky léků   genetika   účinky záření   MeSH
• geny p53 účinky léků   MeSH
• HCT116 buňky MeSH
• ionizující záření MeSH
• lidé MeSH
• nádorový supresorový protein p53 * genetika   metabolismus   fyziologie   MeSH
• nádory nervového systému genetika   MeSH
• nádory tračníku * farmakoterapie   genetika   metabolismus   MeSH
• nádory * genetika   MeSH
• proteinkinasy MeSH
• staurosporin analogy a deriváty   MeSH
• viabilita buněk účinky léků   genetika   účinky záření   MeSH
• Check Tag
• lidé MeSH

OBJECTIVES: This article is to study the role of G(1)/S regulators in differentiation of pluripotent embryonic cells. MATERIALS AND METHODS: We established a P19 embryonal carcinoma cell-based experimental system, which profits from two similar differentiation protocols producing endodermal or neuroectodermal lineages. The levels, mutual interactions, activities, and localization of G(1)/S regulators were analysed with respect to growth and differentiation parameters of the cells. RESULTS AND CONCLUSIONS: We demonstrate that proliferation parameters of differentiating cells correlate with the activity and structure of cyclin A/E-CDK2 but not of cyclin D-CDK4/6-p27 complexes. In an exponentially growing P19 cell population, the cyclin D1-CDK4 complex is detected, which is replaced by cyclin D2/3-CDK4/6-p27 complex following density arrest. During endodermal differentiation kinase-inactive cyclin D2/D3-CDK4-p27 complexes are formed. Neural differentiation specifically induces cyclin D1 at the expense of cyclin D3 and results in predominant formation of cyclin D1/D2-CDK4-p27 complexes. Differentiation is accompanied by cytoplasmic accumulation of cyclin Ds and CDK4/6, which in neural cells are associated with neural outgrowths. Most phenomena found here can be reproduced in mouse embryonic stem cells. In summary, our data demonstrate (i) that individual cyclin D isoforms are utilized in cells lineage specifically, (ii) that fundamental difference in the function of CDK4 and CDK6 exists, and (iii) that cyclin D-CDK4/6 complexes function in the cytoplasm of differentiated cells. Our study unravels another level of complexity in G(1)/S transition-regulating machinery in early embryonic cells.

• MeSH
• biologické modely MeSH
• buněčná diferenciace MeSH
• buněčný rodokmen MeSH
• cyklin A metabolismus   MeSH
• cyklin D1 MeSH
• cyklin E metabolismus   MeSH
• cyklin-dependentní kinasa 4 metabolismus   MeSH
• cyklin-dependentní kinasa 6 metabolismus   MeSH
• cykliny metabolismus   MeSH
• embryo savčí cytologie   metabolismus   MeSH
• embryonální kmenové buňky metabolismus   MeSH
• financování organizované MeSH
• G1 fáze MeSH
• inhibitor p27 cyklin-dependentní kinasy metabolismus   MeSH
• intracelulární prostor metabolismus   MeSH
• lidé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• proliferace buněk MeSH
• S fáze MeSH
• transport proteinů MeSH
• vazba proteinů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH

• MeSH
• apoptóza MeSH
• finanční podpora výzkumu jako téma MeSH
• lidé MeSH
• nádorové buňky kultivované MeSH
• nádorový supresorový protein p53 fyziologie   MeSH
• protoonkogenní proteiny c-bcl-2 genetika   MeSH
• protoonkogenní proteiny genetika   MeSH
• regulace genové exprese MeSH
• železo fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH