Zdravá strava je důležitá pro udržování celkového zdraví a pocitu celkové spokojenosti, prevenci chronických onemocnění, optimalizaci očekávané délky života a klinickou péči o prakticky všechny chorobné stavy. Dietní mýty (tj. představy týkající se výživy, které nejsou podloženy vědeckými důkazy nebo jim odporují) mohou být překážkou pro konzumaci zdravé stravy. Dietní mýty existují v oblasti mikronutrientů, makronutrientů, nevýživových složek a energie získávané z potravy. Příklady mýtů z každé z výše uvedených skupin zahrnují tvrzení, že se pacienti musejí zaměřit na příjem dostatečného množství kalcia, aby měli zdravé kosti, že tuk v potravě vede k obezitě a má škodlivý vliv na zdraví cévních stěn, že veškerá vláknina (ať už přirozeně se vyskytující, nebo dodaná uměle) je prospěšná a že energie přijatá stravou se lineárním vztahem s jednoduchou aritmetikou přeměňuje na kilogramy tělesné hmotnosti. Běžnou oblastí dietních mýtů jsou některé názory výživových poradců, které zdůrazňují vybrané složky stravy v protikladu ke stravě jako celku. Doporučení týkající se zdravé stravy představují celostnější pohled; odpovídající důkazy podporují doporučení omezit příjem výrazně technologicky upravených potravin a naopak doporučují konzumaci minimálně zpracovaných potravin, obecně ve formě, která se co nejvíce blíží té, v jaké se potrava vyskytuje v přírodě. Praktičtí lékaři mohou být pacientům nápomocni vyvracením těchto mýtů a poskytováním rozumných rad týkajících se stravy s tím, že se zaměří na současnou stravu a širší výživové modely.

Healthy dietary intake is important for the maintenance of general health and wellness, the prevention of chronic illness, the optimization of life expectancy, and the clinical management of virtually all disease states. Dietary myths (i.e., concepts about nutrition that are poorly supported or contradicted by scientific evidence) may stand in the way of healthy dietary intake. Dietary myths exist about micronutrients, macronutrients, non-nutrients, and food energy. Representative myths of each type include following: that patients need to focus on consuming enough calcium to ensure bone health, dietary fat leads to obesity and is detrimental to vascular health, all fiber (whether naturally occurring or artificially added) is beneficial, and food calories translate to pounds of body weight through a linear relationship and simple arithmetic. A common theme for dietary myths is a reductionist view of diet that emphasizes selected food constituents as opposed to whole foods. Healthy dietary advice takes a more holistic view; consistent evidence supports recommendations to limit the consumption of ultraprocessed foods and to eat whole or minimally processed foods, generally in a form that is as close to what occurs in nature as possible. Family physicians can help dispel myths for patients and give sound nutritional advice by focusing on actual foods and broader dietary patterns.

• MeSH
• dieta metody   využití   MeSH
• dítě MeSH
• dospělí MeSH
• fyziologie výživy MeSH
• kardiovaskulární nemoci prevence a kontrola   terapie   MeSH
• kostní denzita účinky léků   MeSH
• lidé MeSH
• metaanalýza jako téma MeSH
• mléčné výrobky využití   MeSH
• nedostatek vitaminu D * farmakoterapie   metabolismus   prevence a kontrola   MeSH
• obezita MeSH
• osteoporotické fraktury diagnóza   prevence a kontrola   terapie   MeSH
• osteoporóza diagnóza   metabolismus   prevence a kontrola   MeSH
• postmenopauzální osteoporóza diagnóza   komplikace   prevence a kontrola   MeSH
• potravinářská technologie metody   MeSH
• potravní vláknina * využití   MeSH
• programy na snížení hmotnosti metody   pracovní síly   MeSH
• průzkumy a dotazníky využití   MeSH
• senioři MeSH
• směrnice jako téma MeSH
• syrová strava využití   MeSH
• tuky * aplikace a dávkování   metabolismus   škodlivé účinky   MeSH
• vápník * aplikace a dávkování   metabolismus   škodlivé účinky   MeSH
• výsledek terapie MeSH
• výživová politika * MeSH
• vzdělávání pacientů jako téma MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH

• MeSH
• alfa blokátory MeSH
• beta blokátory MeSH
• biofarmacie MeSH
• dospělí MeSH
• lidé MeSH
• růstový hormon fyziologie   sekrece   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH

Aim: Human induced pluripotent stem cells (iPSCs) are inefficiently derived from somatic cells by overexpression of defined transcription factors. Overexpression of H2A histone variant macroH2A1.1, but not macroH2A1.2, leads to increased iPSC reprogramming by unclear mechanisms. Materials & methods: Cleavage under targets and tagmentation (CUT&Tag) allows robust epigenomic profiling of a low cell number. We performed an integrative CUT&Tag-RNA-Seq analysis of macroH2A1-dependent orchestration of iPSCs reprogramming using human endothelial cells. Results: We demonstrate wider genome occupancy, predicted transcription factors binding, and gene expression regulated by macroH2A1.1 during reprogramming, compared to macroH2A1.2. MacroH2A1.1, previously associated with neurodegenerative pathologies, specifically activated ectoderm/neural processes. Conclusion: CUT&Tag and RNA-Seq data integration is a powerful tool to investigate the epigenetic mechanisms occurring during cell reprogramming.

• MeSH
• endoteliální buňky metabolismus   MeSH
• histony * metabolismus   MeSH
• indukované pluripotentní kmenové buňky * metabolismus   MeSH
• lidé MeSH
• přeprogramování buněk genetika   MeSH
• sekvenování transkriptomu MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Background: Gene expression in eukaryotic cells can be governed by histone variants, which replace replication-coupled histones, conferring unique chromatin properties. MacroH2A1 is a histone H2A variant containing a domain highly similar to H2A and a large non-histone (macro) domain. MacroH2A1, in turn, is present in two alternatively exon-spliced isoforms: macroH2A1.1 and macroH2A1.2, which regulate cell plasticity and proliferation in a remarkably distinct manner. The N-terminal and the C-terminal tails of H2A histones stem from the nucleosome core structure and can be target sites for several post-translational modifications (PTMs). MacroH2A1.1 and macroH2A1.2 isoforms differ only in a few amino acids and their ability to bind NAD-derived metabolites, a property allegedly conferring their different functions in vivo. Some of the modifications on the macroH2A1 variant have been identified, such as phosphorylation (T129, S138) and methylation (K18, K123, K239). However, no study to our knowledge has analyzed extensively, and in parallel, the PTM pattern of macroH2A1.1 and macroH2A1.2 in the same experimental setting, which could facilitate the understanding of their distinct biological functions in health and disease. Methods: We used a mass spectrometry-based approach to identify the sites for phosphorylation, acetylation, and methylation in green fluorescent protein (GFP)-tagged macroH2A1.1 and macroH2A1.2 expressed in human hepatoma cells. The impact of selected PTMs on macroH2A1.1 and macroH2A1.2 structure and function are demonstrated using computational analyses. Results: We identified K7 as a new acetylation site in both macroH2A1 isoforms. Quantitative comparison of histone marks between the two isoforms revealed significant differences in the levels of phosphorylated T129 and S170. Our computational analysis provided evidence that the phosphorylation status in the intrinsically disordered linker region in macroH2A1 isoforms might represent a key regulatory element contributing to their distinct biological responses. Conclusions: Taken together, our results report different PTMs on the two macroH2A1 splicing isoforms as responsible for their distinct features and distribution in the cell.

• Publikační typ
• časopisecké články MeSH

Gene expression and epigenetic processes in several brain regions regulate physiological processes such as cognitive functions and social behavior. MacroH2A1.1 is a ubiquitous variant of histone H2A that regulates cell stemness and differentiation in various organs. Whether macroH2A1.1 has a modulatory role in emotional behavior is unknown. Here, we employed macroH2A1.1 knock-out (-/- ) mice to perform a comprehensive battery of behavioral tests, and an assessment of hippocampal synaptic plasticity (long-term potentiation) accompanied by whole hippocampus RNA sequencing. MacroH2A1.1-/- mice exhibit a stunningly enhancement both of sociability and of active stress-coping behavior, reflected by the increased social behavior in social activity tests and higher mobility time in the forced swim test, respectively. They also display an increased hippocampal synaptic plasticity, accompanied by significant neurotransmission transcriptional networks changes. These results suggest that systemic depletion of histone macroH2A1.1 supports an epigenetic control necessary for hippocampal function and social behavior.

• MeSH
• adaptace psychologická MeSH
• chování zvířat * MeSH
• hipokampus cytologie   MeSH
• histony klasifikace   genetika   metabolismus   MeSH
• myši knockoutované MeSH
• myši MeSH
• neuroplasticita fyziologie   MeSH
• psychický stres MeSH
• regulace genové exprese MeSH
• sociální chování MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Rationale: Loss of histone macroH2A1 induces appearance of cancer stem cells (CSCs)-like cells in hepatocellular carcinoma (HCC). How CSCs interact with the tumor microenvironment and the adaptive immune system is unclear. Methods: We screened aggressive human HCC for macroH2A1 and CD44 CSC marker expression. We also knocked down (KD) macroH2A1 in HCC cells, and performed integrated transcriptomic and secretomic analyses. Results: Human HCC showed low macroH2A1 and high CD44 expression compared to control tissues. MacroH2A1 KD CSC-like cells transferred paracrinally their chemoresistant properties to parental HCC cells. MacroH2A1 KD conditioned media transcriptionally reprogrammed parental HCC cells activated regulatory CD4+/CD25+/FoxP3+ T cells (Tregs). Conclusions: Loss of macroH2A1 in HCC cells drives cancer stem-cell propagation and evasion from immune surveillance.

• MeSH
• antigeny CD44 metabolismus   MeSH
• chemorezistence * MeSH
• forkhead transkripční faktory metabolismus   MeSH
• genový knockdown MeSH
• glykolýza MeSH
• hepatocelulární karcinom farmakoterapie   imunologie   metabolismus   patologie   MeSH
• histony metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• metabolomika metody   MeSH
• nádorové buněčné linie MeSH
• nádorové kmenové buňky účinky léků   imunologie   patologie   MeSH
• nádorové mikroprostředí imunologie   MeSH
• nádory jater farmakoterapie   imunologie   metabolismus   patologie   MeSH
• parakrinní signalizace * MeSH
• receptor interleukinu-2 - alfa-podjednotka metabolismus   MeSH
• regulace genové exprese u nádorů MeSH
• regulační T-lymfocyty imunologie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

DNA damage repair (DDR) is a safeguard for genome integrity maintenance. Increasing DDR efficiency could increase the yield of induced pluripotent stem cells (iPSC) upon reprogramming from somatic cells. The epigenetic mechanisms governing DDR during iPSC reprogramming are not completely understood. Our goal was to evaluate the splicing isoforms of histone variant macroH2A1, macroH2A1.1, and macroH2A1.2, as potential regulators of DDR during iPSC reprogramming. GFP-Trap one-step isolation of mtagGFP-macroH2A1.1 or mtagGFP-macroH2A1.2 fusion proteins from overexpressing human cell lines, followed by liquid chromatography-tandem mass spectrometry analysis, uncovered macroH2A1.1 exclusive interaction with Poly-ADP Ribose Polymerase 1 (PARP1) and X-ray cross-complementing protein 1 (XRCC1). MacroH2A1.1 overexpression in U2OS-GFP reporter cells enhanced specifically nonhomologous end joining (NHEJ) repair pathway, while macroH2A1.1 knock-out (KO) mice showed an impaired DDR capacity. The exclusive interaction of macroH2A1.1, but not macroH2A1.2, with PARP1/XRCC1, was confirmed in human umbilical vein endothelial cells (HUVEC) undergoing reprogramming into iPSC through episomal vectors. In HUVEC, macroH2A1.1 overexpression activated transcriptional programs that enhanced DDR and reprogramming. Consistently, macroH2A1.1 but not macroH2A1.2 overexpression improved iPSC reprogramming. We propose the macroH2A1 splicing isoform macroH2A1.1 as a promising epigenetic target to improve iPSC genome stability and therapeutic potential.

• MeSH
• DNA MeSH
• endoteliální buňky metabolismus   MeSH
• histony * metabolismus   MeSH
• indukované pluripotentní kmenové buňky * metabolismus   MeSH
• lidé MeSH
• myši MeSH
• oprava DNA MeSH
• protein XRCC1 genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Lipid catabolism and anabolism changes play a role in stemness acquisition by cancer cells, and cancer stem cells (CSCs) are particularly dependent on the activity of the enzymes involved in these processes. Lipidomic changes could play a role in CSCs' ability to cause disease relapse and chemoresistance. The exploration of lipid composition and metabolism changes in CSCs in the context of hepatocellular cancer (HCC) is still incomplete and their lipidomic scenario continues to be elusive. We aimed to evaluate through high-throughput mass spectrometry (MS)-based lipidomics the levels of the members of the six major classes of sphingolipids and phospholipids in two HCC cell lines (HepG2 and Huh-7) silenced for the expression of histone variant macroH2A1 (favoring stemness acquisition), or silenced for the expression of focal adhesion tyrosine kinase (FAK) (hindering aggressiveness and stemness). Transcriptomic changes were evaluated by RNA sequencing as well. We found definite lipidomic and transcriptomic changes in the HCC lines upon knockdown (KD) of macroH2A1 or FAK, in line with the acquisition or loss of stemness features. In particular, macroH2A1 KD increased total sphingomyelin (SM) levels and decreased total lysophosphatidylcholine (LPC) levels, while FAK KD decreased total phosphatidylcholine (PC) levels. In conclusion, in HCC cell lines knocked down for specific signaling/epigenetic processes driving opposite stemness potential, we defined a lipidomic signature that hallmarks hepatic CSCs to be exploited for therapeutic strategies.

• MeSH
• buňky Hep G2 MeSH
• fokální adhezní kinasa 1 antagonisté a inhibitory   nedostatek   genetika   MeSH
• fosfatidylcholiny metabolismus   MeSH
• genový knockdown MeSH
• hepatocelulární karcinom genetika   metabolismus   patologie   MeSH
• histony antagonisté a inhibitory   nedostatek   genetika   MeSH
• lidé MeSH
• lipidomika MeSH
• lysofosfatidylcholiny metabolismus   MeSH
• metabolismus lipidů * genetika   MeSH
• nádorové biomarkery genetika   metabolismus   MeSH
• nádorové buněčné linie MeSH
• nádorové kmenové buňky metabolismus   patologie   MeSH
• nádory jater genetika   metabolismus   patologie   MeSH
• regulace genové exprese u nádorů MeSH
• sekvenování transkriptomu MeSH
• sfingomyeliny metabolismus   MeSH
• stanovení celkové genové exprese MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: There is an urgent need to develop better materials to provide anatomical support to the pelvic floor without compromising its function. OBJECTIVE: Our aim was to assess outcomes after simulated vaginal prolapse repair in a sheep model using three different materials: (1) ultra-lightweight polypropylene (PP) non-degradable textile (Restorelle) mesh, (2) electrospun biodegradable ureidopyrimidinone-polycarbonate (UPy-PC), and (3) electrospun non-degradable polyurethane (PU) mesh in comparison with simulated native tissue repair (NTR). These implants may reduce implant-related complications and avoid vaginal function loss. DESIGN, SETTING, AND PARTICIPANTS: A controlled trial was performed involving 48 ewes that underwent NTR or mesh repair with PP, UPy-PC, or PU meshes (n=12/group). Explants were examined 60 and 180 d (six per group) post-implantation. INTERVENTION: Posterior rectovaginal dissection, NTR, or mesh repair. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Implant-related complications, vaginal contractility, compliance, and host response were assessed. Power calculation and analysis of variance testing were used to enable comparison between the four groups. RESULTS: There were no visible implant-related complications. None of the implants compromised vaginal wall contractility, and passive biomechanical properties were similar to those after NTR. Shrinkage over the surgery area was around 35% for NTR and all mesh-augmented repairs. All materials were integrated well with similar connective tissue composition, vascularization, and innervation. The inflammatory response was mild with electrospun implants, inducing both more macrophages yet with relatively more type 2 macrophages present at an early stage than the PP mesh. CONCLUSIONS: Three very different materials were all well tolerated in the sheep vagina. Biomechanical findings were similar for all mesh-augmented repair and NTR. Constructs induced slightly different mid-term inflammatory profiles. PATIENT SUMMARY: Product innovation is needed to reduce implant-related complications. We tested two novel implants, electrospun and an ultra-lightweight polypropylene textile mesh, in a physiologically relevant model for vaginal surgery. All gave encouraging outcomes.

• MeSH
• biokompatibilní materiály MeSH
• chirurgické síťky * MeSH
• gynekologické chirurgické výkony MeSH
• modely nemocí na zvířatech MeSH
• modely u zvířat MeSH
• ovce MeSH
• polypropyleny * MeSH
• prolaps dělohy chirurgie   MeSH
• protézy - design MeSH
• pyrimidinony MeSH
• testování materiálů MeSH
• textilie MeSH
• výsledek terapie MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH

Hepatocellular carcinomas (HCC) contain a subpopulation of cancer stem cells (CSCs), which exhibit stem cell-like features and are responsible for tumor relapse, metastasis, and chemoresistance. The development of effective treatments for HCC will depend on a molecular-level understanding of the specific pathways driving CSC emergence and stemness. MacroH2A1 is a variant of the histone H2A and an epigenetic regulator of stem-cell function, where it promotes differentiation and, conversely, acts as a barrier to somatic-cell reprogramming. Here, we focused on the role played by the histone variant macroH2A1 as a potential epigenetic factor promoting CSC differentiation. In human HCC sections we uncovered a significant correlation between low frequencies of macroH2A1 staining and advanced, aggressive HCC subtypes with poorly differentiated tumor phenotypes. Using HCC cell lines, we found that short hairpin RNA-mediated macroH2A1 knockdown induces acquisition of CSC-like features, including the growth of significantly larger and less differentiated tumors when injected into nude mice. MacroH2A1-depleted HCC cells also exhibited reduced proliferation, resistance to chemotherapeutic agents, and stem-like metabolic changes consistent with enhanced hypoxic responses and increased glycolysis. The loss of macroH2A1 increased expression of a panel of stemness-associated genes and drove hyperactivation of the nuclear factor kappa B p65 pathway. Blocking phosphorylation of nuclear factor kappa B p65 on Ser536 inhibited the emergence of CSC-like features in HCC cells knocked down for macroH2A1. Conclusion: The absence of histone variant macroH2A1 confers a CSC-like phenotype to HCC cells in vitro and in vivo that depends on Ser536 phosphorylation of nuclear factor kappa B p65; this pathway may hold valuable targets for the development of CSC-focused treatments for HCC. (Hepatology 2018;67:636-650).

• MeSH
• buňky Hep G2 MeSH
• fosforylace MeSH
• hepatocelulární karcinom patologie   MeSH
• histony fyziologie   MeSH
• lidé MeSH
• nádorové kmenové buňky patologie   MeSH
• nádory jater patologie   MeSH
• proliferace buněk MeSH
• stanovení celkové genové exprese MeSH
• transkripční faktor RelA metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH