Kooperativer Bibliotheksverbund

Berlin Brandenburg

and
and

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Type of Medium
Language
Year
  • 1
    Language: English
    In: Clinical Reviews in Bone and Mineral Metabolism, 2011, Vol.9(2), pp.94-106
    Description: The human genome encodes 11 cysteine cathepsins belonging to the papain-like family of cysteine peptidases that are known predominantly as endo-lysosomal enzymes. However, it is now understood that the functions and activities of cysteine cathepsins are not limited to endo-lysosomal compartments, as they are also active in the peri- and extracellular space. The thyroid gland is an endocrine organ where such intra- and extracellular proteolytic activities are required to solubilize the prohormone thyroglobulin from its luminal, covalently cross-linked storage forms for subsequent processing into smaller protein fragments and thyroid hormone liberation. Cathepsin K has been identified as one of the cysteine cathepsins with a crucial role in thyroglobulin processing. However, cathepsin K has mainly been a key focus of attention in the last few years because of its high expression in osteoclasts and due to its essential role as collagenase and elastase important for bone remodelling. Besides its remarkable function as an endopeptidase acting on high-molecular mass, covalently cross-linked extracellular substrates such as type I collagen, elastin or thyroglobulin, cathepsin K is also one of the very few proteolytic enzymes that is able to directly liberate thyroxine from thyroglobulin fragments by exopeptidase action. Thus, thyroid cathepsin K is now accepted as a cysteine peptidase with a vital role in liberation of thyroid hormones, which in turn are essential for homoeostasis by triggering a number of important biological processes, ranging from growth and brain development in young vertebrates to tissue remodelling events during morphogenesis or wound healing, as well as control of metabolic pathways and thermoregulation in adults. This review focuses on thyroid cathepsin K and will discuss how localization and trafficking within thyroid epithelial cells explain its thyroid-specific functions. The effects of targeted cathepsin K gene ablation will be summarized from the perspective of the thyroid gland, and we will propose potential consequences of short- and long-term inhibition of thyroid cathepsin K activity for the main thyroid hormone target tissues, namely bone, cardiovascular and immune systems, intestine, and the central nervous system, in addition to the thyroid gland itself.
    Keywords: Cysteine cathepsins ; Extracellular proteolysis ; Thyroid hormones ; Thyroglobulin
    ISSN: 1534-8644
    E-ISSN: 1559-0119
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Language: English
    In: Biological chemistry, September 2012, Vol.393(9), pp.959-70
    Description: Cathepsin K is important for the brain, because its deficiency in mice is associated with a marked decrease in differentiated astrocytes and changes in neuronal patterning in the hippocampus as well as with learning and memory deficits. As cathepsin K activity is most prominent in hippocampal regions of wild type animals, we hypothesised alterations in astrocyte-mediated support of neurons as a potential mechanism underlying the impaired brain functions in cathepsin K-deficient mice. To address this hypothesis, we have generated and characterised astroglia-rich primary cell cultures from cathepsin K-deficient and wild type mice and compared these cultures for possible changes in metabolic support functions and cell composition. Interestingly, cells expressing the oligodendrocytic markers myelin-associated glycoprotein and myelin basic protein were more frequent in astroglia-rich cultures from cathepsin K-deficient mice. However, cell cultures from both genotypes were morphologically comparable and similar with respect to glucose metabolism. In addition, specific glutathione content, glutathione export and γ-glutamyl-transpeptidase activity remained unchanged, whereas the specific activities of glutathione reductase and glutathione-S-transferase were increased by around 50% in cathepsin K-deficient cultures. Thus, lack of cathepsin K in astroglia-rich cultures appears not to affect metabolic supply functions of astrocytes but to facilitate the maturation of oligodendrocytes.
    Keywords: Astrocytes -- Cytology ; Cathepsin K -- Deficiency
    ISSN: 14316730
    E-ISSN: 1437-4315
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Language: English
    In: Cellular and Molecular Life Sciences, 2011, Vol.68(6), pp.1079-1090
    Description: Human cytomegalovirus (HCMV) is a major pathogen in immunocompromised individuals. Here, non-toxic concentrations of the anti-cancer kinase inhibitor sorafenib were shown to inhibit replication of different HCMV strains (including a ganciclovir-resistant strain) in different cell types. In contrast to established anti-HCMV drugs, sorafenib inhibited HCMV major immediate early promoter activity and HCMV immediate early antigen (IEA) expression. Sorafenib is known to inhibit Raf. Comparison of sorafenib with the MEK inhibitor U0126 suggested that sorafenib inhibits HCMV IEA expression through inhibition of Raf but independently of signaling through the Raf downstream kinase MEK 1/2. In concordance, siRNA-mediated depletion of Raf but not of MEK-reduced IEA expression. In conclusion, sorafenib diminished HCMV replication in clinically relevant concentrations and inhibited HCMV IEA expression, a pathophysiologically relevant event that is not affected by established anti-HCMV drugs. Moreover, we demonstrated for the first time that Raf activation is involved in HCMV IEA expression.
    Keywords: Human cytomegalovirus ; Sorafenib ; Kinase inhibitor ; Raf ; Immediate early antigen ; Cancer chemotherapy ; Oncomodulation ; Antiviral therapy
    ISSN: 1420-682X
    E-ISSN: 1420-9071
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Language: English
    In: Neuron, 18 March 2015, Vol.85(6), pp.1177-1192
    Description: Traumatic brain injury (TBI) is linked to several pathologies for which there is a lack of understanding of disease mechanisms and therapeutic strategies. To elucidate injury mechanisms, it is important to consider how physical forces are transmitted and transduced across all spatial scales of the brain. Although the mechanical response of the brain is typically characterized by its material properties and biological structure, cellular mechanotransduction mechanisms also exist. Such mechanisms can affect physiological processes by responding to exogenous mechanical forces directed through sub-cellular components, such as extracellular matrix and cell adhesion molecules, to mechanosensitive intracellular structures that regulate mechanochemical signaling pathways. We suggest that cellular mechanotransduction may be an important mechanism underlying the initiation of cell and sub-cellular injuries ultimately responsible for the diffuse pathological damage and clinical symptoms observed in TBI, thereby providing potential therapeutic opportunities not previously explored in TBI. The disease mechanism of traumatic brain injury is poorly understood and therapeutic interventions are non-existent. Cellular mechanotransduction and the cellular mechanical environment likely play a critical role in pathology and clinical symptoms, yet their explicit involvement remains unexplored.
    Keywords: Biology ; Anatomy & Physiology
    ISSN: 0896-6273
    E-ISSN: 1097-4199
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Language: English
    In: Science (New York, N.Y.), 08 July 2016, Vol.353(6295), pp.158-62
    Description: Inspired by the relatively simple morphological blueprint provided by batoid fish such as stingrays and skates, we created a biohybrid system that enables an artificial animal--a tissue-engineered ray--to swim and phototactically follow a light cue. By patterning dissociated rat cardiomyocytes on an elastomeric body enclosing a microfabricated gold skeleton, we replicated fish morphology at 1/10 scale and captured basic fin deflection patterns of batoid fish. Optogenetics allows for phototactic guidance, steering, and turning maneuvers. Optical stimulation induced sequential muscle activation via serpentine-patterned muscle circuits, leading to coordinated undulatory swimming. The speed and direction of the ray was controlled by modulating light frequency and by independently eliciting right and left fins, allowing the biohybrid machine to maneuver through an obstacle course.
    Keywords: Light ; Robotics ; Tissue Engineering ; Skates (Fish) -- Physiology ; Swimming -- Physiology
    ISSN: 00368075
    E-ISSN: 1095-9203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Language: English
    In: FASEB journal : official publication of the Federation of American Societies for Experimental Biology, January 2014, Vol.28(1), pp.162-75
    Description: Cysteine cathepsins are endolysosomal cysteine proteases highly expressed in macrophages; however, their individual contributions to the elimination of bacteria and bacteria-induced cytokine production by macrophages are unknown. We assessed the contribution of cysteine cathepsins to macrophage defense pathways against Staphylococcus aureus by using chemical inhibitors and by infecting primary bone marrow-derived macrophages deficient in 1 of 7 major macrophage-expressed endolysosomal cysteine proteases. We show that cysteine cathepsins are involved in the phagocytosis and killing of S. aureus. Cathepsin L was identified as an executor of nonoxidative killing. Moreover, microarray data revealed cysteine cathepsins to be important for the maximal induction of certain proinflammatory genes, such as IL6, in response to S. aureus. Cysteine cathepsin's contribution to IL6 production was dependent on phagocytosis, and cathepsin K was identified to be a critical protease in this process. Analysis of macrophages with impaired trafficking of endolysosomal Toll-like receptors (TLRs) to the acidic compartment revealed that they were not involved in cathepsin-dependent IL6 induction. Because IL6 production was completely dependent on the TLR-adaptor protein myeloid differentiation primary response gene 88 (MyD88), it appears that other TLRs are involved. In summary, lysosomal cysteine proteases are functionally linked to the complex bactericidal and inflammatory activities of macrophages.
    Keywords: Innate Immune System ; Lysosome ; Nonoxidative Killing ; Phagocyte ; Proteases ; Cathepsin K -- Metabolism ; Cathepsin L -- Metabolism ; Cytokines -- Metabolism ; Macrophages -- Metabolism ; Phagocytosis -- Physiology ; Staphylococcus Aureus -- Immunology
    ISSN: 08926638
    E-ISSN: 1530-6860
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Language: English
    In: Journal of neurophysiology, 01 March 2017, Vol.117(3), pp.1320-1341
    Description: Brain in vitro models are critically important to developing our understanding of basic nervous system cellular physiology, potential neurotoxic effects of chemicals, and specific cellular mechanisms of many disease states. In this study, we sought to address key shortcomings of current brain in vitro models: the scarcity of comparative data for cells originating from distinct brain regions and the lack of multiregional brain in vitro models. We demonstrated that rat neurons from different brain regions exhibit unique profiles regarding their cell composition, protein expression, metabolism, and electrical activity in vitro. In vivo, the brain is unique in its structural and functional organization, and the interactions and communication between different brain areas are essential components of proper brain function. This fact and the observation that neurons from different areas of the brain exhibit unique behaviors in vitro underline the importance of establishing multiregional brain in vitro models. Therefore, we here developed a multiregional brain-on-a-chip and observed a reduction of overall firing activity, as well as altered amounts of astrocytes and specific neuronal cell types compared with separately cultured neurons. Furthermore, this multiregional model was used to study the effects of phencyclidine, a drug known to induce schizophrenia-like symptoms in vivo, on individual brain areas separately while monitoring downstream effects on interconnected regions. Overall, this work provides a comparison of cells from different brain regions in vitro and introduces a multiregional brain-on-a-chip that enables the development of unique disease models incorporating essential in vivo features. Due to the scarcity of comparative data for cells from different brain regions in vitro, we demonstrated that neurons isolated from distinct brain areas exhibit unique behaviors in vitro. Moreover, in vivo proper brain function is dependent on the connection and communication of several brain regions, underlining the importance of developing multiregional brain in vitro models. We introduced a novel brain-on-a-chip model, implementing essential in vivo features, such as different brain areas and their functional connections.
    Keywords: Brain-on-a-Chip ; Different Brain Regions ; Electrophysiology ; Metabolism ; Protein Expression ; Brain -- Anatomy & Histology ; Neurons -- Classification
    ISSN: 00223077
    E-ISSN: 1522-1598
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Language: English
    In: BMC Neuroscience, July 27, 2011, Vol.12, p.74
    Description: Background Cathepsin K is a cysteine peptidase known for its importance in osteoclast-mediated bone resorption. Inhibitors of cathepsin K are in clinical trials for treatment of osteoporosis. However, side effects of first generation inhibitors included altered levels of related cathepsins in peripheral organs and in the central nervous system (CNS). Cathepsin K has been recently detected in brain parenchyma and it has been linked to neurobehavioral disorders such as schizophrenia. Thus, the study of the functions that cathepsin K fulfils in the brain becomes highly relevant. Results Cathepsin K messenger RNA was detectable in all brain regions of wild type (WT) mice. At the protein level, cathepsin K was detected by immunofluorescence microscopy in vesicles of neuronal and non-neuronal cells throughout the mouse brain. The hippocampus of WT mice exhibited the highest levels of cathepsin K activity in fluorogenic assays, while the cortex, striatum, and cerebellum revealed significantly lower enzymatic activities. At the molecular level, the proteolytic network of cysteine cathepsins was disrupted in the brain of cathepsin K-deficient (Ctsk.sup.-/-.sup.) animals. Specifically, cathepsin B and L protein and activity levels were altered, whereas cathepsin D remained largely unaffected. Cystatin C, an endogenous inhibitor of cysteine cathepsins, was elevated in the striatum and hippocampus, pointing to regional differences in the tissue response to Ctsk ablation. Decreased levels of astrocytic glial fibrillary acidic protein, fewer and less ramified profiles of astrocyte processes, differentially altered levels of oligodendrocytic cyclic nucleotide phosphodiesterase, as well as alterations in the patterning of neuronal cell layers were observed in the hippocampus of Ctsk.sup.-/- .sup.mice. A number of molecular and cellular changes were detected in other brain regions, including the cortex, striatum/mesencephalon, and cerebellum. Moreover, an overall induction of the dopaminergic system was found in Ctsk.sup.-/- .sup.animals which exhibited reduced anxiety levels as well as short- and long-term memory impairments in behavioral assessments. Conclusion We conclude that deletion of the Ctsk gene can lead to deregulation of related proteases, resulting in a wide range of molecular and cellular changes in the CNS with severe consequences for tissue homeostasis. We propose that cathepsin K activity has an important impact on the development and maintenance of the CNS in mice.
    Keywords: Cathepsins -- Research ; Cathepsins -- Physiological Aspects ; Cathepsins -- Health Aspects ; Learning Disorders -- Risk Factors ; Learning Disorders -- Development And Progression ; Learning Disorders -- Care And Treatment ; Learning Disorders -- Research ; Memory Disorders -- Risk Factors ; Memory Disorders -- Development And Progression ; Memory Disorders -- Care And Treatment ; Memory Disorders -- Research
    ISSN: 1471-2202
    Source: Cengage Learning, Inc.
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Language: English
    In: BMC Neuroscience, July 27, 2011, Vol.12, p.74
    Description: Background Cathepsin K is a cysteine peptidase known for its importance in osteoclast-mediated bone resorption. Inhibitors of cathepsin K are in clinical trials for treatment of osteoporosis. However, side effects of first generation inhibitors included altered levels of related cathepsins in peripheral organs and in the central nervous system (CNS). Cathepsin K has been recently detected in brain parenchyma and it has been linked to neurobehavioral disorders such as schizophrenia. Thus, the study of the functions that cathepsin K fulfils in the brain becomes highly relevant. Results Cathepsin K messenger RNA was detectable in all brain regions of wild type (WT) mice. At the protein level, cathepsin K was detected by immunofluorescence microscopy in vesicles of neuronal and non-neuronal cells throughout the mouse brain. The hippocampus of WT mice exhibited the highest levels of cathepsin K activity in fluorogenic assays, while the cortex, striatum, and cerebellum revealed significantly lower enzymatic activities. At the molecular level, the proteolytic network of cysteine cathepsins was disrupted in the brain of cathepsin K-deficient (Ctsk.sup.-/-.sup.) animals. Specifically, cathepsin B and L protein and activity levels were altered, whereas cathepsin D remained largely unaffected. Cystatin C, an endogenous inhibitor of cysteine cathepsins, was elevated in the striatum and hippocampus, pointing to regional differences in the tissue response to Ctsk ablation. Decreased levels of astrocytic glial fibrillary acidic protein, fewer and less ramified profiles of astrocyte processes, differentially altered levels of oligodendrocytic cyclic nucleotide phosphodiesterase, as well as alterations in the patterning of neuronal cell layers were observed in the hippocampus of Ctsk.sup.-/- .sup.mice. A number of molecular and cellular changes were detected in other brain regions, including the cortex, striatum/mesencephalon, and cerebellum. Moreover, an overall induction of the dopaminergic system was found in Ctsk.sup.-/- .sup.animals which exhibited reduced anxiety levels as well as short- and long-term memory impairments in behavioral assessments. Conclusion We conclude that deletion of the Ctsk gene can lead to deregulation of related proteases, resulting in a wide range of molecular and cellular changes in the CNS with severe consequences for tissue homeostasis. We propose that cathepsin K activity has an important impact on the development and maintenance of the CNS in mice.
    Keywords: Osteoporosis ; Enzymes ; Intermediate Filament Proteins ; Brain ; Messenger Rna ; Cystine ; Medical Research ; Neurons ; Schizophrenia ; Cysteine ; Animal Behavior ; Cathepsins
    ISSN: 1471-2202
    Source: Cengage Learning, Inc.
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    In: Journal of Comparative Neurology, 01 May 2016, Vol.524(7), pp.1309-1336
    Description: In the brain, extracellular matrix (ECM) components form networks that contribute to structural and functional diversity. Maladaptive remodeling of ECM networks has been reported in neurodegenerative and psychiatric disorders, suggesting that the brain microenvironment is a dynamic structure. A lack of quantitative information about ECM distribution in the brain hinders an understanding of region‐specific ECM functions and the role of ECM in health and disease. We hypothesized that each ECM protein as well as specific ECM structures, such as perineuronal nets (PNNs) and interstitial matrix, are differentially distributed throughout the brain, contributing to the unique structure and function in the various regions of the brain. To test our hypothesis, we quantitatively analyzed the distribution, colocalization, and protein expression of aggrecan, brevican, and tenascin‐R throughout the rat brain utilizing immunohistochemistry and mass spectrometry analysis and assessed the effect of aggrecan, brevican, and/or tenascin‐R on neurite outgrowth in vitro. We focused on aggrecan, brevican, and tenascin‐R as they are especially expressed in the mature brain, and have established roles in brain development, plasticity, and neurite outgrowth. The results revealed a differentiated distribution of all three proteins throughout the brain and indicated that their presence significantly reduces neurite outgrowth in a 3D in vitro environment. These results underline the importance of a unique and complex ECM distribution for brain physiology and suggest that encoding the distribution of distinct ECM proteins throughout the brain will aid in understanding their function in physiology and in turn assist in identifying their role in disease. J. Comp. Neurol. 524:1309–1336, 2016. © 2016 Wiley Periodicals, Inc. The authors identified a brain region–specific distribution of ECM proteins, suggesting the existence of a complex and tightly controlled network with specific functions of this network in distinct brain regions. In turn, this information provides a basis to identify ECM alterations in disease and the consequences thereof.
    Keywords: Aggrecan ; Brain Extracellular Matrix ; Brevican ; Perineuronal Nets ; Tenascin‐R ; Rrid: Ab_90460 ; Rrid: Ab_398211 ; Rrid: Ab_2207009
    ISSN: 0021-9967
    E-ISSN: 1096-9861
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages