Cancer cells facilitate tumor growth by creating favorable tumor micro-environments (TME), altering homeostasis and immune response in the extracellular matrix (ECM) of surrounding tissue. A potential factor that contributes to TME generation and ECM remodeling is the cytoskeleton-associated human death-associated protein kinase 1 (DAPK1). Increased tumor cell motility and de-adhesion (thus, promoting metastasis), as well as upregulated plasminogen-signaling, are shown when functionally analyzing the DAPK1 ko-related proteome. However, the systematic investigation of how tumor cells actively modulate the ECM at the tissue level is experimentally challenging since animal models do not allow direct experimental access while artificial in vitro scaffolds cannot simulate the entire complexity of tissue systems. Here, we used the chorioallantoic membrane (CAM) assay as a natural, collagen-rich tissue model in combination with all-optical experimental access by multiphoton microscopy (MPM) to study the ECM remodeling potential of colorectal tumor cells with and without DAPK1 in situ and even in vivo. This approach demonstrates the suitability of the CAM assay in combination with multiphoton microscopy for studying collagen remodeling during tumor growth. Our results indicate the high ECM remodeling potential of DAPK1 ko tumor cells at the tissue level and support our findings from proteomics.

• Klíčová slova
• ECM remodeling, MPM, collagen, colon cancer, uPAR,
• Publikační typ
• časopisecké články MeSH

Chronic renal failure (CRF) is associated with an increased incidence of cardiovascular diseases. Intensive research revealed a number of alterations in the heart during CRF; however, possible interventricular differences in CRF-induced cardiac remodeling have so far not been addressed. CRF was induced by two-stage surgical 5/6 nephrectomy (NX) in male Wistar rats. Cellular hypertrophy was quantified using immunohistological morphometric analysis. Contraction force and membrane potential were recorded in left and right ventricle papillary muscles with an isometric force transducer and high-resistance glass microelectrodes. Hypertrophy was present in the left ventricle (LV) of NX animals, but not in the right ventricle (RV) of NX animals, as documented by both ventricle/body weight ratios and cellular morphometric analysis of the cross-sectional area of myocytes. The contraction force was reduced in the LV of NX animals but increased in the RV of NX animals compared with sham-operated rats. Rest potentiation of contraction force was relatively more pronounced in the LV of NX rats. Fifty percent substitution of extracellular sodium with lithium significantly increased the contraction force only in the LV of NX animals. Action potential durations were shortened in both ventricles of CRF animals. Cardiac structural and contractile remodeling in CRF shows significant interventricular differences. CRF induces hypertrophy of the LV but not of the RV. LV hypertrophy was associated with a reduction of contraction force, whereas in the RV, the contraction force was enhanced. Partial recovery of contractile function of the LV by rest potentiation or lithium substitution indicates a role of the Na(+)/Ca(2+) exchanger in this phenomenon.

• MeSH
• chronické selhání ledvin komplikace   patofyziologie   MeSH
• hypertenze MeSH
• hypertrofie levé komory srdeční komplikace   patofyziologie   MeSH
• kardiovaskulární nemoci komplikace   patofyziologie   MeSH
• kontrakce myokardu MeSH
• krysa rodu Rattus MeSH
• membránové potenciály MeSH
• náhodné rozdělení MeSH
• nefrektomie MeSH
• potkani Wistar MeSH
• remodelace komor * MeSH
• sloučeniny lithia farmakologie   MeSH
• srdce - funkce komor MeSH
• srdeční komory patofyziologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• sloučeniny lithia MeSH

A new study has uncovered three mechanisms of motor-independent membrane tubulation. In vitro reconstitution using a minimal set of proteins shows that the accumulation of crosslinking proteins at the membrane-microtubule interface is sufficient to drive tubulation, which is enhanced by coupling with microtubule dynamics.

• MeSH
• mikrotubuly * MeSH
• proteiny * MeSH
• Publikační typ
• časopisecké články MeSH
• komentáře MeSH
• Názvy látek
• proteiny * 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.

• Klíčová slova
• F-Actin remodeling, Rho associated protein kinase, RhoGTPases, Tau, glial degeneration, membrane blebbing, tauopathies,
• 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
• Názvy látek
• aktiny MeSH
• kinázy asociované s rho MeSH
• proteiny tau MeSH
• rhoA protein vázající GTP MeSH
• tubulin MeSH
• výměnné faktory guaninnukleotidů MeSH
• zelené fluorescenční proteiny MeSH

Regulation of axon guidance and pruning of inappropriate synapses by class 3 semaphorins are key to the development of neural circuits. Collapsin response mediator protein 2 (CRMP2) has been shown to regulate axon guidance by mediating semaphorin 3A (Sema3A) signaling; however, nothing is known about its role in synapse pruning. Here, using newly generated crmp2-/- mice we demonstrate that CRMP2 has a moderate effect on Sema3A-dependent axon guidance in vivo, and its deficiency leads to a mild defect in axon guidance in peripheral nerves and the corpus callosum. Surprisingly, crmp2-/- mice display prominent defects in stereotyped axon pruning in hippocampus and visual cortex and altered dendritic spine remodeling, which is consistent with impaired Sema3F signaling and with models of autism spectrum disorder (ASD). We demonstrate that CRMP2 mediates Sema3F signaling in primary neurons and that crmp2-/- mice display ASD-related social behavior changes in the early postnatal period as well as in adults. Together, we demonstrate that CRMP2 mediates Sema3F-dependent synapse pruning and its dysfunction shares histological and behavioral features of ASD.

• Klíčová slova
• axon guidance, collapsin response mediator protein 2, dendritic spines, semaphorins, synapse pruning,
• MeSH
• dendritické trny MeSH
• membránové proteiny fyziologie   MeSH
• mezibuněčné signální peptidy a proteiny genetika   MeSH
• myši knockoutované MeSH
• myši MeSH
• neurony MeSH
• neuroplasticita MeSH
• poruchy autistického spektra * MeSH
• proteiny nervové tkáně genetika   fyziologie   MeSH
• semaforiny * MeSH
• signální transdukce MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• collapsin response mediator protein-2 MeSH Prohlížeč
• membránové proteiny MeSH
• mezibuněčné signální peptidy a proteiny MeSH
• proteiny nervové tkáně MeSH
• Sema3f protein, mouse MeSH Prohlížeč
• semaforiny * MeSH

Lipoid character of plasma membrane namely the presence of polyenic fatty acids enables to interact with membrane proteins and in certain extent also to modulate their function. During the development, molecules of membrane fatty acids become more and more complex, and the ratio of polyenic fatty acids/saturated fatty acids in the brain rises, while the concentration of monoenic fatty acids remained relatively stable. This phenomenon is apparent also in the ratio of unsaturated fatty acids OMEGA-3 in plasma of newborns which correlates with the birth weight. Plasma membrane reflects local specializations of nerve cells. Its composition varies in functionally specialized regions called domains. Specialized domains of nerve cells determine the function of dendrites, soma, axon, axon hillock ect. Premature weaning of laboratory rats results in structural changes and in the increase of excitability of neuronal circuits in hypothalamus, septum and hippocampus which indicate the possibility of membrane composition changes. In synapses, transport proteins of synaptic vesicles, act together with the specific proteins of the presynaptic membrane. Membrane proteins determine the release of neurotransmitter at different conditions of synaptic activity, and they can contribute to the recovery of neurotransmitter content after the repeated hyperactivity. In the model of experimental kindling, repeated seizures bring about decreases and distribution changes of synaptic vesicles.

• MeSH
• buněčná membrána fyziologie   MeSH
• lidé MeSH
• lipidové dvojvrstvy MeSH
• membránové proteiny fyziologie   MeSH
• neurony fyziologie   MeSH
• neuroplasticita fyziologie   MeSH
• synapse fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• lipidové dvojvrstvy MeSH
• membránové proteiny MeSH

BACKGROUND: Bronchial epithelial reticular basement membrane (RBM) thickening occurs in diseases with both eosinophilic (allergic bronchial asthma [BA]) and neutrophilic (cystic fibrosis [CF] and primary ciliary dyskinesia [PCD]) chronic airway inflammation; however, the lung function and airway remodeling relation remains unclear. The aim of this study was to test whether ventilation inhomogeneity is related to RBM thickening. METHODS: Multiple breath washout test, endobronchial biopsy, and BAL were performed in 24 children with CF, 11 with PCD, 15 with BA, and in 19 control subjects. Lung clearance index at 2.5% (1/40th) of starting nitrogen concentration (LCI2.5), RBM thickness, and lavage fluid cytology were quantified; their mutual associations were studied by using Spearman rank correlations (r). RESULTS: In asthma, ventilation inhomogeneity (mean ± SD) was mild (LCI2.5, 9.3 ± 1.4 vs 7.9 ± 0.9 in control subjects; P = .0391), and the RBM thickened (5.26 ± 0.98 μm vs 3.12 ± 0.62 μm in control subjects; P < .0001). No relation between RBM thickness and ventilation inhomogeneity or lavage cytology was found. In CF and PCD, RBM thickness was similar to that in asthma (4.54 ± 0.66 μm and 5.27 ± 1.11 μm, respectively), but ventilation inhomogeneity was significantly higher (LCI2.5, 12.5 ± 2.4 and 11.8 ± 2.5). Both in CF and PCD, RBM thickness correlated with LCI2.5 (r = 0.594, P = .015; r = 0.821, P = .023). In PCD only, RBM thickness was also related to the number of neutrophils in lavage fluid (r = 0.821; P = .023). CONCLUSIONS: Lung function impairment in relation to RBM thickness was milder in BA than in CF and PCD. In asthma, ventilation inhomogeneity did not correlate with RBM thickness, whereas it did in CF and PCD. This outcome suggests a different structure-function relation in these diseases.

• Klíčová slova
• airway remodeling, bronchial asthma, cystic fibrosis, multiple breath washout test, primary ciliary dyskinesia, reticular basement membrane thickening,
• MeSH
• bazální membrána patologie   MeSH
• biopsie metody   MeSH
• bronchiální astma * patologie   patofyziologie   MeSH
• bronchoalveolární lavážní tekutina MeSH
• bronchoskopie MeSH
• bronchy * patologie   patofyziologie   MeSH
• cystická fibróza * patologie   patofyziologie   MeSH
• dítě MeSH
• korelace dat MeSH
• lidé MeSH
• mukociliární clearance MeSH
• neutrofily patologie   MeSH
• plicní ventilace fyziologie   MeSH
• poruchy ciliární motility * patologie   patofyziologie   MeSH
• remodelace dýchacích cest MeSH
• respirační funkční testy metody   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Mechanosensory ion channels are proteins that are sensitive to mechanical forces. They are found in tissues throughout the body and play an important role in bone remodeling by sensing changes in mechanical stress and transmitting signals to bone-forming cells. Orthodontic tooth movement (OTM) is a prime example of mechanically induced bone remodeling. However, the cell-specific role of the ion channels Piezo1 and Piezo2 in OTM has not been investigated yet. Here we first identify the expression of PIEZO1/2 in the dentoalveolar hard tissues. Results showed that PIEZO1 was expressed in odontoblasts, osteoblasts, and osteocytes, while PIEZO2 was localized in odontoblasts and cementoblasts. We therefore used a Piezo1floxed/floxed mouse model in combination with Dmp1cre to inactivate Piezo1 in mature osteoblasts/cementoblasts, osteocytes/cementocytes, and odontoblasts. Inactivation of Piezo1 in these cells did not affect the overall morphology of the skull but caused significant bone loss in the craniofacial skeleton. Histological analysis revealed a significantly increased number of osteoclasts in Piezo1floxed/floxed;Dmp1cre mice, while osteoblasts were not affected. Despite this increased number of osteoclasts, orthodontic tooth movement was not altered in these mice. Our results suggest that despite Piezo1 being crucial for osteoclast function, it may be dispensable for mechanical sensing of bone remodeling.

• MeSH
• buňky pojivové tkáně * MeSH
• iontové kanály MeSH
• myši MeSH
• osteoblasty * MeSH
• osteocyty MeSH
• osteoklasty MeSH
• remodelace kosti MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• iontové kanály MeSH
• Piezo1 protein, mouse MeSH Prohlížeč

The aim of present study was to investigate functional and physical alterations in membranes of heart mitochondria that are associated with remodeling of these organelles in acute phase of streptozotocin-induced diabetes and to elucidate the role of these changes in adaptation of the heart to acute streptozotocin-induced diabetes (evaluated 8 days after single dose streptozotocin application to male Wistar rats). Action of free radicals on the respiratory chain of diabetic-heart mitochondria was manifested by 17 % increase (p<0.05) in oxidized form of the coenzyme Q(10) and resulted in a decrease of states S3 and S4 respiration, the respiratory control index, rate of phosphorylation (all p<0.01) and the mitochondrial transmembrane potential (p<0.05), but the ADP/O ratio decreased only moderately (p>0.05). On the contrary, membrane fluidity and the total mitochondrial Mg2+-ATPase activity increased (both p<0.05). In diabetic heart mitochondria, linear regression analysis revealed a reciprocal relationship between the increase in membrane fluidity and decrease in trans-membrane potential (p<0.05, r = 0.67). Changes in membrane fluidity, transmembrane potential, Mg2+-ATPase activity and the almost preserved ADP/O ratio appear as the manifestation of endogenous protective mechanisms participating in the functional remodeling of mitochondria which contributes to adaptation of the heart to diabetes.

• MeSH
• Ca(2+)-Mg(2+)-ATPasa metabolismus   MeSH
• experimentální diabetes mellitus metabolismus   patofyziologie   MeSH
• fluidita membrány MeSH
• fyziologická adaptace MeSH
• krysa rodu Rattus MeSH
• membránový potenciál mitochondrií MeSH
• mitochondriální membrány metabolismus   MeSH
• myokard enzymologie   metabolismus   MeSH
• oxidativní fosforylace MeSH
• potkani Wistar MeSH
• srdeční mitochondrie enzymologie   metabolismus   MeSH
• transport elektronů MeSH
• ubichinon analogy a deriváty   metabolismus   MeSH
• volné radikály metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• Ca(2+)-Mg(2+)-ATPasa MeSH
• coenzyme Q10 MeSH Prohlížeč
• ubichinon MeSH
• volné radikály MeSH

Changes in environmental temperature represent one of the major stresses faced by microorganisms as they affect the function of the cytoplasmic membrane. In this study, we have analyzed the thermal adaptation in two closely related respiratory pathogens Bordetella pertussis and Bordetella bronchiseptica Although B. pertussis represents a pathogen strictly adapted to the human body temperature, B. bronchiseptica causes infection in a broad range of animals and survives also outside of the host. We applied GC-MS to determine the fatty acids of both Bordetella species grown at different temperatures and analyzed the membrane fluidity by fluorescence anisotropy measurement. In parallel, we also monitored the effect of growth temperature changes on the expression and production of several virulence factors. In response to low temperatures, B. pertussis adapted its fatty acid composition and membrane fluidity to a considerably lesser extent when compared with B. bronchiseptica Remarkably, B. pertussis maintained the production of virulence factors at 24 °C, whereas B. bronchiseptica cells resumed the production only upon temperature upshift to 37 °C. This growth temperature-associated differential modulation of virulence factor production was linked to the phosphorylation state of transcriptional regulator BvgA. The observed differences in low-temperature adaptation between B. pertussis and B. bronchiseptica may result from selective adaptation of B. pertussis to the human host. We propose that the reduced plasticity of the B. pertussis membranes ensures sustained production of virulence factors at suboptimal temperatures and may play an important role in the transmission of the disease.

• Klíčová slova
• bacterial pathogenesis, bacterial signal transduction, fatty acid, host adaptation, membrane function, virulence factor,
• MeSH
• aklimatizace * MeSH
• anizotropie MeSH
• bakteriální proteiny metabolismus   MeSH
• Bordetella bronchiseptica cytologie   fyziologie   MeSH
• Bordetella pertussis cytologie   fyziologie   MeSH
• buněčná membrána metabolismus   MeSH
• cytoplazma metabolismus   MeSH
• druhová specificita MeSH
• faktory virulence metabolismus   MeSH
• fluorescenční spektrometrie MeSH
• fosforylace MeSH
• lidé MeSH
• mastné kyseliny chemie   MeSH
• plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
• signální transdukce MeSH
• tělesná teplota MeSH
• teplota * MeSH
• transkripční faktory metabolismus   MeSH
• virulence MeSH
• životní prostředí MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• BvgA protein, Bacteria MeSH Prohlížeč
• faktory virulence MeSH
• mastné kyseliny MeSH
• transkripční faktory MeSH