Structural neuroplasticity such as neurite extension and dendritic spine dynamics is enhanced by brain-derived neurotrophic factor (BDNF) and impaired by types of inhibitory molecules that induce growth cone collapse and actin depolymerization, for example, myelin-associated inhibitors, chondroitin sulfate proteoglycans, and negative guidance molecules. These inhibitory molecules can activate RhoA/rho-associated coiled-coil containing protein kinase (ROCK) signaling (known to restrict structural plasticity). Intermittent hypoxia (IH) and high-intensity interval training (HIIT) are known to upregulate BDNF that is associated with improvements in learning and memory and greater functional recovery following neural insults. We investigated whether the RhoA/ROCK signaling pathway is also modulated by IH and HIIT in the hippocampus, cortex, and lumbar spinal cord of male Wistar rats. The gene expression of 25 RhoA/ROCK signaling pathway components was determined following IH, HIIT, or IH combined with HIIT (30 min/day, 5 days/wk, 6 wk). IH included 10 3-min bouts that alternated between hypoxia (15% O2) and normoxia. HIIT included 10 3-min bouts alternating between treadmill speeds of 50 cm·s-1 and 15 cm·s-1. In the hippocampus, IH and HIIT significantly downregulated Acan and NgR2 mRNA that are involved in the inhibition of neuroplasticity. However, IH and IH + HIIT significantly upregulated Lingo-1 and NgR3 in the cortex. This is the first time IH and HIIT have been linked to the modulation of plasticity-inhibiting pathways. These results provide a fundamental step toward elucidating the interplay between the neurotrophic and inhibitory mechanisms involved in experience-driven neural plasticity that will aid in optimizing physiological interventions for the treatment of cognitive decline or neurorehabilitation.NEW & NOTEWORTHY Intermittent hypoxia (IH) and high-intensity interval training (HIIT) enhance neuroplasticity and upregulate neurotrophic factors in the central nervous system (CNS). We provide evidence that IH and IH + HIIT also have the capacity to regulate genes involved in the RhoA/ROCK signaling pathway that is known to restrict structural plasticity in the CNS. This provides a new mechanistic insight into how these interventions may enhance hippocampal-related plasticity and facilitate learning, memory, and neuroregeneration.
- MeSH
- hipokampus * metabolismus MeSH
- hypoxie metabolismus patofyziologie MeSH
- kinázy asociované s rho * metabolismus genetika MeSH
- krysa rodu rattus MeSH
- mícha metabolismus fyziologie MeSH
- mozková kůra metabolismus fyziologie MeSH
- neuroplasticita fyziologie MeSH
- potkani Wistar * MeSH
- rho proteiny vázající GTP MeSH
- rhoA protein vázající GTP metabolismus MeSH
- signální transdukce * fyziologie MeSH
- vysoce intenzivní intervalový trénink * MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Breast cancer is the most prevalent cancer type in women worldwide. It proliferates rapidly and can metastasize into farther tissues at any stage due to the gradual invasiveness and motility of the tumor cells. These crucial properties are the outcome of the weakened intercellular adhesion, regulated by small guanosine triphosphatases (GTPases), which hydrolyze to the guanosine diphosphate (GDP)-bound conformation. We investigated the inactivating effect of ARHGAP1 on Rho GTPases involved signaling pathways after treatment with a high dose of doxorubicin. Label-free quantitative proteomic analysis of the proteome isolated from the MCF-7 breast cancer cell line, treated with 1 μM of doxorubicin, identified RAC1, CDC42, and RHOA GTPases that were inactivated by the ARHGAP1 protein. Upregulation of the GTPases involved in the transforming growth factor-beta (TGF-beta) signaling pathway initiated epithelial-mesenchymal transitions. These findings demonstrate a key role of the ARHGAP1 protein in the disruption of the cell adhesion and simultaneously allow for a better understanding of the molecular mechanism of the reduced cell adhesion leading to the subsequent metastasis. The conclusions of this study corroborate the hypothesis that chemotherapy with doxorubicin may increase the risk of metastases in drug-resistant breast cancer cells.
- MeSH
- cdc42 protein vázající GTP metabolismus MeSH
- doxorubicin farmakologie MeSH
- lidé MeSH
- MFC-7 buňky MeSH
- nádory prsu * farmakoterapie MeSH
- proteiny aktivující GTPasu * metabolismus MeSH
- proteomika MeSH
- rac1 protein vázající GTP metabolismus MeSH
- rho proteiny vázající GTP * metabolismus MeSH
- rhoA protein vázající GTP metabolismus MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
ARHGAP42 encodes Rho GTPase activating protein 42 that belongs to a member of the GTPase Regulator Associated with Focal Adhesion Kinase (GRAF) family. ARHGAP42 is involved in blood pressure control by regulating vascular tone. Despite these findings, disorders of human variants in the coding part of ARHGAP42 have not been reported. Here, we describe an 8-year-old girl with childhood interstitial lung disease (chILD), systemic hypertension, and immunological findings who carries a homozygous stop-gain variant (c.469G>T, p.(Glu157Ter)) in the ARHGAP42 gene. The family history is notable for both parents with hypertension. Histopathological examination of the proband lung biopsy showed increased mural smooth muscle in small airways and alveolar septa, and concentric medial hypertrophy in pulmonary arteries. ARHGAP42 stop-gain variant in the proband leads to exon 5 skipping, and reduced ARHGAP42 levels, which was associated with enhanced RhoA and Cdc42 expression. This is the first report linking a homozygous stop-gain variant in ARHGAP42 with a chILD disorder, systemic hypertension, and immunological findings in human patient. Evidence of smooth muscle hypertrophy on lung biopsy and an increase in RhoA/ROCK signaling in patient cells suggests the potential mechanistic link between ARHGAP42 deficiency and the development of chILD disorder.
- MeSH
- dítě MeSH
- homozygot MeSH
- hypertenze genetika MeSH
- intersticiální plicní nemoci genetika patologie MeSH
- leukocytóza genetika imunologie MeSH
- lidé MeSH
- lymfocytóza genetika imunologie MeSH
- myši MeSH
- proteiny aktivující GTPasu genetika MeSH
- rhoA protein vázající GTP genetika metabolismus MeSH
- rodokmen MeSH
- sekvenování exomu MeSH
- zvířata MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Directional migration during embryogenesis and tumor progression faces the challenge that numerous external signals need to converge to precisely control cell movement. The Rho guanine exchange factor (GEF) Trio is especially well suited to relay signals, as it features distinct catalytic domains to activate Rho GTPases. Here, we show that Trio is required for Xenopus cranial neural crest (NC) cell migration and cartilage formation. Trio cell-autonomously controls protrusion formation of NC cells and Trio morphant NC cells show a blebbing phenotype. Interestingly, the Trio GEF2 domain is sufficient to rescue protrusion formation and migration of Trio morphant NC cells. We show that this domain interacts with the DEP/C-terminus of Dishevelled (DVL). DVL - but not a deletion construct lacking the DEP domain - is able to rescue protrusion formation and migration of Trio morphant NC cells. This is likely mediated by activation of Rac1, as we find that DVL rescues Rac1 activity in Trio morphant embryos. Thus, our data provide evidence for a novel signaling pathway, whereby Trio controls protrusion formation of cranial NC cells by interacting with DVL to activate Rac1.
- MeSH
- crista neuralis cytologie embryologie MeSH
- fenotyp MeSH
- HEK293 buňky MeSH
- lidé MeSH
- plazmidy genetika MeSH
- pohyb buněk genetika MeSH
- protein dishevelled genetika metabolismus MeSH
- protein-serin-threoninkinasy genetika metabolismus MeSH
- proteinové domény MeSH
- proteiny Xenopus genetika metabolismus MeSH
- rac1 protein vázající GTP metabolismus MeSH
- rhoA protein vázající GTP metabolismus MeSH
- signální transdukce genetika MeSH
- transfekce MeSH
- vazba proteinů genetika MeSH
- výměnné faktory guaninnukleotidů genetika metabolismus MeSH
- Xenopus laevis embryologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Benzimidazole anthelmintics flubendazole and mebendazole are microtubule-targeting drugs that showed considerable anti-cancer activity in different preclinical models. In this study, the effects of flubendazole and mebendazole on proliferation, migration and cadherin switching were studied in a panel of oral cell lines in vitro. Both compounds reduced the viability of the PE/CA-PJ15 and H376 oral squamous carcinoma cells and of the premalignant oral keratinocytes DOK with the IC50 values in the range of 0.19-0.26 μM. Normal oral keratinocytes and normal gingival fibroblasts were less sensitive to the treatment. Flubendazole and mebendazole also reduced the migration of the PE/CA-PJ15 cell in concentrations that had no anti-migratory effects on the normal gingival fibroblasts. Levels of the focal adhesion kinase FAK, Rho-A and Rac1 GTPases and the Rho guanine nucleotide exchange factor GEF-H1 were decreased in both PE/CA-PJ15 cells and gingival fibroblasts following treatment. Both drugs also interfered with cadherin switching in the model of TGF-β-induced epithelial to mesenchymal transition (EMT) in the DOK cell line. Levels of N-cadherin were reduced in the TGF-β induced cells co-treated with flubendazol and mebendazole in very low concentration (50 nM). These results suggest direct effects of both benzimidazoles on selected processes of EMT in oral cell lines such as cadherin switching as well as cellular migration.
- MeSH
- buněčné linie MeSH
- cdc42 protein vázající GTP metabolismus MeSH
- epitelo-mezenchymální tranzice účinky léků MeSH
- fokální adhezní kinasa 1 metabolismus MeSH
- kadheriny metabolismus MeSH
- lidé MeSH
- mebendazol analogy a deriváty farmakologie MeSH
- nádory úst metabolismus patologie MeSH
- pohyb buněk účinky léků MeSH
- proliferace buněk účinky léků MeSH
- rhoA protein vázající GTP metabolismus MeSH
- spinocelulární karcinom metabolismus patologie MeSH
- transformující růstový faktor beta farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Classical Hodgkin lymphoma (cHL) has a typical clinical manifestation, with dissemination involving functionally neighboring lymph nodes. The factors involved in the spread of lymphoma cells are poorly understood. Here we show that cHL cell lines migrate with higher rates compared with non-Hodgkin lymphoma cell lines. cHL cell migration, invasion and adhesion depend on autocrine WNT signaling as revealed by the inhibition of WNT secretion with the porcupine inhibitors Wnt-C59/IWP-2, but did not affect cell proliferation. While application of recombinant WNT5A or WNT5A overexpression stimulates HL cell migration, neither WNT10A, WNT10B nor WNT16 did so. Time-lapse studies revealed an amoeboid type of cell migration modulated by WNT5A. Reduced migration distances and velocity of cHL cells, as well as altered movement patterns, were observed using porcupine inhibitor or WNT5A antagonist. Knockdown of Frizzled5 and Dishevelled3 disrupted the WNT5A-mediated RHOA activation and cell migration. Overexpression of DVL3-K435M or inhibition of ROCK (Rho-associated protein kinase) by Y-27632/H1152P disrupted cHL cell migration. In addition to these mechanistic insights into the role of WNT5A in vitro, global gene expression data revealed an increased WNT5A expression in primary HL cells in comparison with normal B-cell subsets and other lymphomas. Furthermore, the activity of both porcupine and WNT5A in cHL cells had an impact on lymphoma development in the chick chorionallantoic membrane assay. Massive bleeding of these lymphomas was significantly reduced after inhibition of WNT secretion by Wnt-C59. Therefore, a model is proposed where WNT signaling has an important role in regulating tumor-promoting processes.
- MeSH
- biologické modely MeSH
- biopsie MeSH
- buněčná adheze genetika MeSH
- dikobrazovití a urzonovití MeSH
- exprese genu MeSH
- frizzled receptory metabolismus MeSH
- Hodgkinova nemoc diagnostické zobrazování genetika metabolismus patologie MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- počítačová rentgenová tomografie MeSH
- pohyb buněk genetika MeSH
- proliferace buněk MeSH
- protein dishevelled metabolismus MeSH
- protein Wnt 5a genetika metabolismus MeSH
- rhoA protein vázající GTP metabolismus MeSH
- signální transdukce MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The tyrosine kinase Src acts as a key regulator of cell motility by phosphorylating multiple protein substrates that control cytoskeletal and adhesion dynamics. In an earlier phosphotyrosine proteomics study, we identified a novel Rho-GTPase activating protein, now known as ARHGAP42, as a likely biologically relevant Src substrate. ARHGAP42 is a member of a family of RhoGAPs distinguished by tandem BAR-PH domains lying N-terminal to the GAP domain. Like other family members, ARHGAP42 acts preferentially as a GAP for RhoA. We show that Src principally phosphorylates ARHGAP42 on tyrosine 376 (Tyr-376) in the short linker between the BAR-PH and GAP domains. The expression of ARHGAP42 variants in mammalian cells was used to elucidate its regulation. We found that the BAR domain is inhibitory toward the GAP activity of ARHGAP42, such that BAR domain deletion resulted in decreased active GTP-bound RhoA and increased cell motility. With the BAR domain intact, ARHGAP42 GAP activity could be activated by phosphorylation of Tyr-376 to promote motile cell behavior. Thus, phosphorylation of ARHGAP42 Tyr-376 is revealed as a novel regulatory event by which Src can affect actin dynamics through RhoA inhibition.
- MeSH
- fokální adheze metabolismus MeSH
- fosforylace MeSH
- lidé MeSH
- myši MeSH
- pohyb buněk fyziologie MeSH
- proteiny aktivující GTPasu genetika metabolismus MeSH
- rho proteiny vázající GTP antagonisté a inhibitory metabolismus MeSH
- rhoA protein vázající GTP antagonisté a inhibitory metabolismus MeSH
- skupina kinas odvozených od src-genu metabolismus MeSH
- tyrosin metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Hippo effectors YAP/TAZ act as on-off mechanosensing switches by sensing modifications in extracellular matrix (ECM) composition and mechanics. The regulation of their activity has been described by a hierarchical model in which elements of Hippo pathway are under the control of focal adhesions (FAs). Here we unveil the molecular mechanism by which cell spreading and RhoA GTPase activity control FA formation through YAP to stabilize the anchorage of the actin cytoskeleton to the cell membrane. This mechanism requires YAP co-transcriptional function and involves the activation of genes encoding for integrins and FA docking proteins. Tuning YAP transcriptional activity leads to the modification of cell mechanics, force development and adhesion strength, and determines cell shape, migration and differentiation. These results provide new insights into the mechanism of YAP mechanosensing activity and qualify this Hippo effector as the key determinant of cell mechanics in response to ECM cues.
- MeSH
- buněčná diferenciace genetika fyziologie MeSH
- buněčná membrána metabolismus MeSH
- buněčné linie MeSH
- buněčný převod mechanických signálů genetika fyziologie MeSH
- extracelulární matrix metabolismus MeSH
- fokální adheze genetika metabolismus fyziologie MeSH
- HEK293 buňky MeSH
- jaderné proteiny genetika metabolismus MeSH
- lidé MeSH
- mikrofilamenta metabolismus MeSH
- nádorové buněčné linie MeSH
- pohyb buněk genetika fyziologie MeSH
- rhoA protein vázající GTP genetika metabolismus MeSH
- stanovení celkové genové exprese MeSH
- transkripční faktory genetika metabolismus MeSH
- tvar buňky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Abnormal aggregation of Tau in glial cells has been reported in Alzheimer's disease (AD) and other tauopathies; however, the pathological significance of these aggregates remains unsolved to date. In this study, we evaluated whether full-length Tau (Tau441) and its aspartic acid421-truncated Tau variant (Tau421) produce alterations in the normal organization of the cytoskeleton and plasma membrane (PM) when transiently expressed in cultured C6-glial cells. Forty-eight hours post-transfection, abnormal microtubule bundling was observed in the majority of the cells, which expressed either Tau441 or Tau421. Moreover, both variants of Tau produced extensive PM blebbing associated with cortical redistribution of filamentous actin (F-Actin). These effects were reverted when Tau-expressing cells were incubated with drugs that depolymerize F-Actin. In addition, when glial cells showing Tau-induced PM blebbing were incubated with inhibitors of the Rho-associated protein kinase (ROCK) signaling pathway, both formation of abnormal PM blebs and F-Actin remodeling were avoided. All of these effects were initiated upstream by abnormal Tau-induced microtubule bundling, which may release the microtubule-bound guanine nucleotide exchange factor-H1 (GEF-H1) into the cytoplasm in order to activate its major effector RhoA-GTPase. These results may represent a new mechanism of Tau toxicity in which Tau-induced microtubule bundling produces activation of the Rho-GTPase-ROCK pathway that in turn mediates the remodeling of cortical Actin and PM blebbing. In AD and other tauopathies, these Tau-induced abnormalities may occur and contribute to the impairment of glial activity.
- MeSH
- aktiny účinky léků metabolismus MeSH
- buněčná membrána účinky léků metabolismus patologie MeSH
- buněčné linie MeSH
- cytoplazma metabolismus MeSH
- elektroforéza MeSH
- fluorescenční protilátková technika MeSH
- kinázy asociované s rho metabolismus MeSH
- koncové značení zlomů DNA in situ MeSH
- konfokální mikroskopie MeSH
- krysa rodu rattus MeSH
- neuroglie účinky léků metabolismus patologie MeSH
- proteiny tau genetika metabolismus MeSH
- rhoA protein vázající GTP metabolismus MeSH
- signální transdukce účinky léků MeSH
- transfekce MeSH
- tubulin metabolismus MeSH
- výměnné faktory guaninnukleotidů metabolismus MeSH
- western blotting MeSH
- zelené fluorescenční proteiny genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Altered calcium sensitization (mediated by RhoA/Rho-kinase pathway) and enhanced calcium entry through L-type voltage-dependent calcium channels (L-VDCCs) participate in blood pressure (BP) maintenance of adult spontaneously hypertensive rats (SHRs). This study aimed to evaluate ontogenetic changes of these two pathways in BP control of SHR and Wistar-Kyoto (WKY) aged 3, 5, 7, 13, 26 and 42 weeks. METHODS: BP response to acute administration of Rho-kinase inhibitor fasudil or L-VDCC blocker nifedipine and the expression of particular components of RhoA/Rho-kinase pathway were determined in young and adult animals. RESULTS: Fasudil-induced BP reduction was attenuated in young SHR compared with WKY, but was enhanced in adult SHR. In contrast, BP response to nifedipine was similar in 3-week-old SHR and WKY and it was augmented with age in SHR but not in WKY. Consequently, the ratio between fasudil-induced and nifedipine-induced BP changes was lower in all age groups of SHR compared with WKY. Fasudil effects on contractility of isolated arteries were attenuated in young but not in adult SHR. mRNA expression of selected Rho-GEFs (Arhgef1, Arhgef11 and Arhgef12) was decreased only in adult SHR, whereas p63RhoGEF and CPI-17 expression was reduced in both age groups of SHR. Active RhoA and phosphorylated CPI-17 were increased in adult but not in young SHR. CONCLUSION: The importance of RhoA/Rho-kinase pathway for BP/vascular tone control is attenuated in SHR from prehypertensive stages. Enhanced RhoA activation and/or CPI-17 phosphorylation might be counteracted by reduced expression of upstream activators of Rho-kinase (Rho-GEFs) together with lower expression of CPI-17 (in downstream cascade of Rho-kinase).
- MeSH
- 1-(5-isochinolinsulfonyl)-2-methylpiperazin analogy a deriváty farmakologie MeSH
- arterie účinky léků patofyziologie MeSH
- blokátory kalciových kanálů farmakologie MeSH
- exprese genu účinky léků MeSH
- faktory zaměňující Rho guanin nukleotidy genetika MeSH
- fosfoproteiny genetika metabolismus MeSH
- fosforylace MeSH
- hypertenze patofyziologie MeSH
- inhibitory proteinkinas farmakologie MeSH
- kinázy asociované s rho antagonisté a inhibitory metabolismus MeSH
- krevní tlak účinky léků fyziologie MeSH
- krysa rodu rattus MeSH
- messenger RNA metabolismus MeSH
- nifedipin farmakologie MeSH
- potkani inbrední SHR MeSH
- potkani inbrední WKY MeSH
- rhoA protein vázající GTP metabolismus MeSH
- signální transdukce MeSH
- svalová kontrakce MeSH
- svalové proteiny genetika metabolismus MeSH
- svaly hladké cévní účinky léků fyziologie MeSH
- vápník metabolismus MeSH
- vápníkové kanály - typ L účinky léků metabolismus MeSH
- výměnné faktory guaninnukleotidů genetika MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH