scholarly journals Reconsideration of the Semaphorin-3A Binding Motif Found in Chondroitin Sulfate Using Galnac4s-6st-Knockout Mice

Biomolecules ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1499
Author(s):  
Satomi Nadanaka ◽  
Shinji Miyata ◽  
Bai Yaqiang ◽  
Jun-ichi Tamura ◽  
Osami Habuchi ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Chondroitin Sulfate ◽  
Knockout Mice ◽  
Neuronal Plasticity ◽  
Binding Motif ◽  
Semaphorin 3A ◽  
Wild Type ◽  
Perineuronal Net ◽  
Wisteria Floribunda

The chondroitin sulfate (CS)-rich dense extracellular matrix surrounding neuron cell bodies and proximal dendrites in a mesh-like structure is called a perineuronal net (PNN). CS chains in PNNs control neuronal plasticity by binding to PNN effectors, semaphorin-3A (Sema3A) and orthodenticle homeobox 2. Sema3A recognizes CS-containing type-E disaccharide units (sulfated at O-4 and O-6 of N-acetylgalactosamine). Type-E disaccharide units are synthesized by N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase (GalNAc4S-6ST). In this study, we demonstrated that Sema3A accumulates in the PNNs surrounding parvalbumin cells, even in mice deficient in GalNAc4S-6ST. In addition, there were no differences in the number and structure of PNNs visualized by Cat316 antibody and Wisteria floribunda lectin, which recognize CS chains, between wild type and GalNAc4S-6ST knockout mice. Therefore, we re-examined the Sema3A binding motif found in CS chains using chemically synthesized CS tetrasaccharides. As a result, we found that non-sulfated GalNAc residues at the non-reducing termini of CS chains are required for the binding of Sema3A.

scholarly journals Tenascin-R promotes assembly of the extracellular matrix of perineuronal nets via clustering of aggrecan

2014 ◽  
Vol 369 (1654) ◽  
pp. 20140046 ◽  
Author(s):  
Markus Morawski ◽  
Alexander Dityatev ◽  
Maike Hartlage-Rübsamen ◽  
Maren Blosa ◽  
Max Holzer ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Neurological Disorders ◽  
Polyclonal Antibodies ◽  
Brain Slices ◽  
Perineuronal Nets ◽  
Wild Type ◽  
Extracellular Matrix Molecules ◽  
Histological Appearance ◽  
Organotypic Slice Cultures ◽  
Wisteria Floribunda

Perineuronal nets (PNs) in the brains of tenascin-R-deficient ( tn-r −/− ) mice develop in temporal concordance with those of wild-type ( tn-r +/+ ) mice. However, the histological appearance of PNs is abnormal in adult tn-r −/− mice. Here, we investigated whether similar defects are also seen in dissociated and organotypic cultures from hippocampus and forebrain of tn-r −/− mice and whether the structure of PNs could be normalized. In tn-r −/− cultures, accumulations of several extracellular matrix molecules were mostly associated with somata, whereas dendrites were sparsely covered, compared with tn-r +/+ mice. Experiments to normalize the structure of PNs in tn-r −/− organotypic slice cultures by depolarization of neurons, or by co-culturing tn-r +/+ and tn-r −/− brain slices failed to restore a normal PN phenotype. However, formation of dendritic PNs in cultures was improved by the application of tenascin-R protein and rescued by polyclonal antibodies to aggrecan and a bivalent, but not monovalent form of the lectin Wisteria floribunda agglutinin. These results show that tenascin-R and aggrecan are decisive contributors to formation and stabilization of PNs and that tenascin-R may implement these functions by clustering of aggrecan. Proposed approaches for restoration of normal PN structure are noteworthy in the context of PN abnormalities in neurological disorders, such as epilepsy, schizophrenia and addiction.

scholarly journals Chondroitin Sulfate Induces Depression of Synaptic Transmission and Modulation of Neuronal Plasticity in Rat Hippocampal Slices

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Elisa Albiñana ◽  
Javier Gutierrez-Luengo ◽  
Natalia Hernández-Juarez ◽  
Andrés M. Baraibar ◽  
Eulalia Montell ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Synaptic Transmission ◽  
Neuronal Plasticity ◽  
Chondroitin Sulphate ◽  
Hippocampal Slices ◽  
Long Term Potentiation ◽  
Dependent Manner ◽  
Perineuronal Net ◽  
Concentration Dependent Manner ◽  
Population Spike Amplitude

It is currently known that in CNS the extracellular matrix is involved in synaptic stabilization and limitation of synaptic plasticity. However, it has been reported that the treatment with chondroitinase following injury allows the formation of new synapses and increased plasticity and functional recovery. So, we hypothesize that some components of extracellular matrix may modulate synaptic transmission. To test this hypothesis we evaluated the effects of chondroitin sulphate (CS) on excitatory synaptic transmission, cellular excitability, and neuronal plasticity using extracellular recordings in the CA1 area of rat hippocampal slices. CS caused a reversible depression of evoked field excitatory postsynaptic potentials in a concentration-dependent manner. CS also reduced the population spike amplitude evoked after orthodromic stimulation but not when the population spikes were antidromically evoked; in this last case a potentiation was observed. CS also enhanced paired-pulse facilitation and long-term potentiation. Our study provides evidence that CS, a major component of the brain perineuronal net and extracellular matrix, has a function beyond the structural one, namely, the modulation of synaptic transmission and neuronal plasticity in the hippocampus.

scholarly journals Chondroitin sulfate N-acetylgalactosaminyltransferase-1 is required for normal cartilage development

2010 ◽  
Vol 432 (1) ◽  
pp. 47-55 ◽  
Author(s):  
Yumi Watanabe ◽  
Kosei Takeuchi ◽  
Susumu Higa Onaga ◽  
Michiko Sato ◽  
Mika Tsujita ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Chondroitin Sulfate ◽  
Type Ii Collagen ◽  
Short Chain ◽  
Type Ii ◽  
Wild Type ◽  
Collagen Fibres ◽  
Normal Cartilage ◽  
Cartilage Development ◽  
Homozygous Mutant

CS (chondroitin sulfate) is a glycosaminoglycan species that is widely distributed in the extracellular matrix. To understand the physiological roles of enzymes involved in CS synthesis, we produced CSGalNAcT1 (CS N-acetylgalactosaminyltransferase 1)-null mice. CS production was reduced by approximately half in CSGalNAcT1-null mice, and the amount of short-chain CS was also reduced. Moreover, the cartilage of the null mice was significantly smaller than that of wild-type mice. Additionally, type-II collagen fibres in developing cartilage were abnormally aggregated and disarranged in the homozygous mutant mice. These results suggest that CSGalNAcT1 is required for normal CS production in developing cartilage.

scholarly journals Chondroitin 6-Sulfation Regulates Perineuronal Net Formation by Controlling the Stability of Aggrecan

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Shinji Miyata ◽  
Hiroshi Kitagawa
Keyword(s):  
Extracellular Matrix ◽  
Chondroitin Sulfate ◽  
Neural Plasticity ◽  
Adult Brain ◽  
Chondroitin Sulfate Proteoglycans ◽  
Perineuronal Nets ◽  
Perineuronal Net ◽  
A Disintegrin And Metalloproteinase ◽  
The Stability ◽  
Thrombospondin Motif

Perineuronal nets (PNNs) are lattice-like extracellular matrix structures composed of chondroitin sulfate proteoglycans (CSPGs). The appearance of PNNs parallels the decline of neural plasticity, and disruption of PNNs reactivates neural plasticity in the adult brain. We previously reported that sulfation patterns of chondroitin sulfate (CS) chains on CSPGs influenced the formation of PNNs and neural plasticity. However, the mechanism of PNN formation regulated by CS sulfation remains unknown. Here we found that overexpression of chondroitin 6-sulfotransferase-1 (C6ST-1), which catalyzes 6-sulfation of CS chains, selectively decreased aggrecan, a major CSPG in PNNs, in the aged brain without affecting other PNN components. Both diffuse and PNN-associated aggrecans were reduced by overexpression of C6ST-1. C6ST-1 increased 6-sulfation in both the repeating disaccharide region and linkage region of CS chains. Overexpression of 6-sulfation primarily impaired accumulation of aggrecan in PNNs, whereas condensation of other PNN components was not affected. Finally, we found that increased 6-sulfation accelerated proteolysis of aggrecan by a disintegrin and metalloproteinase domain with thrombospondin motif (ADAMTS) protease. Taken together, our results indicate that sulfation patterns of CS chains on aggrecan influenced the stability of the CSPG, thereby regulating formation of PNNs and neural plasticity.

scholarly journals IL-17F depletion accelerates chitosan conduit guided peripheral nerve regeneration

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Feixiang Chen ◽  
Weihuang Liu ◽  
Qiang Zhang ◽  
Ping Wu ◽  
Ao Xiao ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Sciatic Nerve ◽  
Peripheral Nerve ◽  
Nerve Regeneration ◽  
Knockout Mice ◽  
Inflammatory Markers ◽  
Nerve Repair ◽  
Peripheral Nerve Regeneration ◽  
Wild Type ◽  
Anti Inflammatory

AbstractPeripheral nerve injury is a serious health problem and repairing long nerve deficits remains a clinical challenge nowadays. Nerve guidance conduit (NGC) serves as the most promising alternative therapy strategy to autografts but its repairing efficiency needs improvement. In this study, we investigated whether modulating the immune microenvironment by Interleukin-17F (IL-17F) could promote NGC mediated peripheral nerve repair. Chitosan conduits were used to bridge sciatic nerve defect in IL-17F knockout mice and wild-type mice with autografts as controls. Our data revealed that IL-17F knockout mice had improved functional recovery and axonal regeneration of sciatic nerve bridged by chitosan conduits comparing to the wild-type mice. Notably, IL-17F knockout mice had enhanced anti-inflammatory macrophages in the NGC repairing microenvironment. In vitro data revealed that IL-17F knockout peritoneal and bone marrow derived macrophages had increased anti-inflammatory markers after treatment with the extracts from chitosan conduits, while higher pro-inflammatory markers were detected in the Raw264.7 macrophage cell line, wild-type peritoneal and bone marrow derived macrophages after the same treatment. The biased anti-inflammatory phenotype of macrophages by IL-17F knockout probably contributed to the improved chitosan conduit guided sciatic nerve regeneration. Additionally, IL-17F could enhance pro-inflammatory factors production in Raw264.7 cells and wild-type peritoneal macrophages. Altogether, IL-17F may partially mediate chitosan conduit induced pro-inflammatory polarization of macrophages during nerve repair. These results not only revealed a role of IL-17F in macrophage function, but also provided a unique and promising target, IL-17F, to modulate the microenvironment and enhance the peripheral nerve regeneration.

scholarly journals A Rubisco-binding protein is required for normal pyrenoid number and starch sheath morphology inChlamydomonas reinhardtii

2019 ◽  
Vol 116 (37) ◽  
pp. 18445-18454 ◽  
Author(s):  
Alan K. Itakura ◽  
Kher Xing Chan ◽  
Nicky Atkinson ◽  
Leif Pallesen ◽  
Lianyong Wang ◽  
...  
Keyword(s):  
Surface Area ◽  
Structure And Function ◽  
Binding Motif ◽  
Starch Granules ◽  
Wild Type ◽  
Bisphosphate Carboxylase ◽  
Biophysical Mechanism ◽  
Mechanism Function ◽  
And Function

A phase-separated, liquid-like organelle called the pyrenoid mediates CO2fixation in the chloroplasts of nearly all eukaryotic algae. While most algae have 1 pyrenoid per chloroplast, here we describe a mutant in the model algaChlamydomonasthat has on average 10 pyrenoids per chloroplast. Characterization of the mutant leads us to propose a model where multiple pyrenoids are favored by an increase in the surface area of the starch sheath that surrounds and binds to the liquid-like pyrenoid matrix. We find that the mutant’s phenotypes are due to disruption of a gene, which we call StArch Granules Abnormal 1 (SAGA1) because starch sheath granules, or plates, in mutants lacking SAGA1 are more elongated and thinner than those of wild type. SAGA1 contains a starch binding motif, suggesting that it may directly regulate starch sheath morphology. SAGA1 localizes to multiple puncta and streaks in the pyrenoid and physically interacts with the small and large subunits of the carbon-fixing enzyme Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase), a major component of the liquid-like pyrenoid matrix. Our findings suggest a biophysical mechanism by which starch sheath morphology affects pyrenoid number and CO2-concentrating mechanism function, advancing our understanding of the structure and function of this biogeochemically important organelle. More broadly, we propose that the number of phase-separated organelles can be regulated by imposing constraints on their surface area.

Ascorbic acid and CoQ10 ameliorate the reproductive ability of superoxide dismutase 1-deficient female mice†

2019 ◽  
Author(s):  
Naoki Ishii ◽  
Takujiro Homma ◽  
Jaeyong Lee ◽  
Hikaru Mitsuhashi ◽  
Ken-ichi Yamada ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Superoxide Dismutase ◽  
Coenzyme Q10 ◽  
Knockout Mice ◽  
Knockout Mouse ◽  
Superoxide Dismutase 1 ◽  
Wild Type ◽  
Positive Effects ◽  
Reproductive Ability ◽  
Ascorbic Acid Supplementation

Abstract Superoxide dismutase 1 suppresses oxidative stress within cells by decreasing the levels of superoxide anions. A dysfunction of the ovary and/or an aberrant production of sex hormones are suspected causes for infertility in superoxide dismutase 1-knockout mice. We report on attempts to rescue the infertility in female knockout mice by providing two antioxidants, ascorbic acid and/or coenzyme Q10, as supplements in the drinking water of the knockout mice after weaning and on an investigation of their reproductive ability. On the first parturition, 80% of the untreated knockout mice produced smaller litter sizes compared with wild-type mice (average 2.8 vs 7.3 pups/mouse), and supplementing with these antioxidants failed to improve these litter sizes. However, in the second parturition of the knockout mice, the parturition rate was increased from 18% to 44–75% as the result of the administration of antioxidants. While plasma levels of progesterone at 7.5 days of pregnancy were essentially the same between the wild-type and knockout mice and were not changed by the supplementation of these antioxidants, sizes of corpus luteum cells, which were smaller in the knockout mouse ovaries after the first parturition, were significantly ameliorated in the knockout mouse with the administration of the antioxidants. Moreover, the impaired vasculogenesis in uterus/placenta was also improved by ascorbic acid supplementation. We thus conclude that ascorbic acid and/or coenzyme Q10 are involved in maintaining ovarian and uterus/placenta homeostasis against insults that are augmented during pregnancy and that their use might have positive effects in terms of improving female fertility.

scholarly journals Activation of microglia induces symptoms of Parkinson’s disease in wild-type, but not in IL-1 knockout mice

2013 ◽  
Vol 10 (1) ◽  
Author(s):  
Sachiko Tanaka ◽  
Atsuko Ishii ◽  
Hirokazu Ohtaki ◽  
Seiji Shioda ◽  
Takemi Yoshida ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Knockout Mice ◽  
Wild Type

scholarly journals Food restriction by intermittent fasting induces diabetes and obesity and aggravates spontaneous atherosclerosis development in hypercholesterolaemic mice

2013 ◽  
Vol 111 (6) ◽  
pp. 979-986 ◽  
Author(s):  
Gabriel G. Dorighello ◽  
Juliana C. Rovani ◽  
Christopher J. F. Luhman ◽  
Bruno A. Paim ◽  
Helena F. Raposo ◽  
...  
Keyword(s):  
Knockout Mice ◽  
Plasma Levels ◽  
Food Restriction ◽  
Ldl Receptor ◽  
Intermittent Fasting ◽  
Wild Type ◽  
Obesity And Diabetes ◽  
Ad Libitum ◽  
Atherosclerosis Development ◽  
Ldl Receptor Knockout Mice

Different regimens of food restriction have been associated with protection against obesity, diabetes and CVD. In the present study, we hypothesised that food restriction would bring benefits to atherosclerosis- and diabetes-prone hypercholesterolaemic LDL-receptor knockout mice. For this purpose, 2-month-old mice were submitted to an intermittent fasting (IF) regimen (fasting every other day) over a 3-month period, which resulted in an overall 20 % reduction in food intake. Contrary to our expectation, epididymal and carcass fat depots and adipocyte size were significantly enlarged by 15, 72 and 68 %, respectively, in the IF mice compared with the ad libitum-fed mice. Accordingly, plasma levels of leptin were 50 % higher in the IF mice than in the ad libitum-fed mice. In addition, the IF mice showed increased plasma levels of total cholesterol (37 %), VLDL-cholesterol (195 %) and LDL-cholesterol (50 %). As expected, in wild-type mice, the IF regimen decreased plasma cholesterol levels and epididymal fat mass. Glucose homeostasis was also disturbed by the IF regimen in LDL-receptor knockout mice. Elevated levels of glycaemia (40 %), insulinaemia (50 %), glucose intolerance and insulin resistance were observed in the IF mice. Systemic inflammatory markers, TNF-α and C-reactive protein, were significantly increased and spontaneous atherosclerosis development were markedly increased (3-fold) in the IF mice. In conclusion, the IF regimen induced obesity and diabetes and worsened the development of spontaneous atherosclerosis in LDL-receptor knockout mice. Although being efficient in a wild-type background, this type of food restriction is not beneficial in the context of genetic hypercholesterolaemia.

Sign in / Sign up

Export Citation Format

Share Document