Hypoxia is involved in the regulation of stem cell fate, and hypoxia-inducible factor 1 (HIF-1) is the master regulator of hypoxic response. Here, we focus on the effect of hypoxia on intracellular signaling pathways responsible for mouse embryonic stem (ES) cell maintenance. We employed wild-type and HIF-1α-deficient ES cells to investigate hypoxic response in the ERK, Akt, and STAT3 pathways. Cultivation in 1% O2 for 24 h resulted in the strong dephosphorylation of ERK and its upstream kinases and to a lesser extent of Akt in an HIF-1-independent manner, while STAT3 phosphorylation remained unaffected. Downregulation of ERK could not be mimicked either by pharmacologically induced hypoxia or by the overexpression. Dual-specificity phosphatases (DUSP) 1, 5, and 6 are hypoxia-sensitive MAPK-specific phosphatases involved in ERK downregulation, and protein phosphatase 2A (PP2A) regulates both ERK and Akt. However, combining multiple approaches, we revealed the limited significance of DUSPs and PP2A in the hypoxia-mediated attenuation of ERK signaling. Interestingly, we observed a decreased reactive oxygen species (ROS) level in hypoxia and a similar phosphorylation pattern for ERK when the cells were supplemented with glutathione. Therefore, we suggest a potential role for the ROS-dependent attenuation of ERK signaling in hypoxia, without the involvement of HIF-1.

• MeSH
• down regulace MeSH
• faktor 1 indukovatelný hypoxií - podjednotka alfa metabolismus   MeSH
• mitogenem aktivované proteinkinasy kinas metabolismus   MeSH
• myší embryonální kmenové buňky metabolismus   MeSH
• myši MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• signální transdukce MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• faktor 1 indukovatelný hypoxií - podjednotka alfa MeSH
• mitogenem aktivované proteinkinasy kinas MeSH
• reaktivní formy kyslíku MeSH

PURPOSE: Although beneficial effects of the dietary n-3 docosahexaenoic acid (DHA) or butyrate in colon carcinogenesis have been implicated, the mechanisms of their action are not fully clear. Here, we investigated modulations of composition of individual phospholipid (PL) classes, with a particular emphasis on cardiolipins (CLs), in colon cells treated with DHA, sodium butyrate (NaBt), or their combination (DHA/NaBt), and we evaluated possible associations between lipid changes and cell fate after fatty acid treatment. METHODS: In two distinct human colon cell models, foetal colon (FHC) and adenocarcinoma (HCT-116) cells, we compared patterns and composition of individual PL classes following the fatty acid treatment by HPLC-MS/MS. In parallel, we measured the parameters reflecting cell proliferation, differentiation and death. RESULTS: In FHC cells, NaBt induced primarily differentiation, while co-treatment with DHA shifted their response towards cell death. In contrast, NaBt induced apoptosis in HCT-116 cells, which was not further affected by DHA. DHA was incorporated in all main PL types, increasing their unsaturation, while NaBt did not additionally modulate these effects in either cell model. Nevertheless, we identified an unusually wide range of CL species to be highly increased by NaBt and particularly by DHA/NaBt, and these effects were more pronounced in HCT-116 cells. DHA and DHA/NaBt enhanced levels of high molecular weight and more unsaturated CL species, containing DHA, which was specific for either differentiation or apoptotic responses. CONCLUSIONS: We identified a wide range of CL species in the colon cells which composition was significantly modified after DHA and NaBt treatment. These specific CL modulations might contribute to distinct cellular differentiation or apoptotic responses.

• Klíčová slova
• Apoptosis, Butyrate, Cardiolipins, Colon cancer, Docosahexaenoic acid, Phospholipids,
• MeSH
• apoptóza účinky léků   MeSH
• buněčná diferenciace účinky léků   MeSH
• fosfolipidy chemie   MeSH
• HCT116 buňky MeSH
• kaspasa 3 genetika   metabolismus   MeSH
• kolon cytologie   účinky léků   MeSH
• kyselina máselná farmakologie   MeSH
• kyseliny dokosahexaenové farmakologie   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• proliferace buněk účinky léků   MeSH
• tandemová hmotnostní spektrometrie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• CASP3 protein, human MeSH Prohlížeč
• fosfolipidy MeSH
• kaspasa 3 MeSH
• kyselina máselná MeSH
• kyseliny dokosahexaenové MeSH

Alkaline phosphatase is an enzyme commonly expressed in almost all living organisms. In humans and other mammals, determinations of the expression and activity of alkaline phosphatase have frequently been used for cell determination in developmental studies and/or within clinical trials. Alkaline phosphatase also seems to be one of the key markers in the identification of pluripotent embryonic stem as well as related cells. However, alkaline phosphatases exist in some isoenzymes and isoforms, which have tissue specific expressions and functions. Here, the role of alkaline phosphatase as a stem cell marker is discussed in detail. First, we briefly summarize contemporary knowledge of mammalian alkaline phosphatases in general. Second, we focus on the known facts of its role in and potential significance for the identification of stem cells.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Intestinal homeostasis is precisely regulated by a number of endogenous regulatory molecules but significantly influenced by dietary compounds. Malfunction of this system may result in chronic inflammation and cancer. Dietary essential n-3 polyunsaturated fatty acids (PUFAs) and short-chain fatty acid butyrate produced from fibre display anti-inflammatory and anticancer activities. Both compounds were shown to modulate the production and activities of TNF family cytokines. Cytokines from the TNF family (TNF- α, TRAIL, and FasL) have potent inflammatory activities and can also regulate apoptosis, which plays an important role in cancer development. The results of our own research showed enhancement of apoptosis in colon cancer cells by a combination of either docosahexaenoic acid (DHA) or butyrate with TNF family cytokines, especially by promotion of the mitochondrial apoptotic pathway and modulation of NF κ B activity. This review is focused mainly on the interaction of dietary PUFAs and butyrate with these cytokines during colon inflammation and cancer development. We summarised recent knowledge about the cellular and molecular mechanisms involved in such effects and outcomes for intestinal cell behaviour and pathologies. Finally, the possible application for the prevention and therapy of colon inflammation and cancer is also outlined.

• MeSH
• apoptóza MeSH
• butyráty metabolismus   MeSH
• cytokiny metabolismus   MeSH
• dieta MeSH
• kolon patologie   MeSH
• kyseliny dokosahexaenové metabolismus   MeSH
• lidé MeSH
• mitochondrie patologie   MeSH
• myši MeSH
• nádory metabolismus   MeSH
• nenasycené mastné kyseliny metabolismus   MeSH
• NF-kappa B metabolismus   MeSH
• střevní sliznice metabolismus   MeSH
• tumor nekrotizující faktory metabolismus   MeSH
• zánět metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• butyráty MeSH
• cytokiny MeSH
• kyseliny dokosahexaenové MeSH
• nenasycené mastné kyseliny MeSH
• NF-kappa B MeSH
• tumor nekrotizující faktory MeSH