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    ADAMTS1, ADAMTS5, ADAMTS9 and aggrecanase-generated proteoglycan fragments are induced following spinal cord injury in mouse
    (Elsevier Ireland Ltd, 2013) Demircan, Kadir; Yonezawa, Tomoko; Takigawa, Tomoyuki; Topcu, Vehap; Erdogan, Serpil; Ucar, Fatma; Armutcu, Ferah
    ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) proteinases are involved in a variety of biological processes such as angiogenesis, cancer and arthritis. ADAMTSs appears to be responsible for the cleavage of proteoglycans in several tissues including brain and cartilage. Chondroitin sulfate proteoglycans (CSPGs) maintains the integrity of the brain extracellular matrix and major inhibitory contributors for glial scar and neural plasticity. The activity of aggrecanases in the central nervous system (CNS)has been reported. ADAMTSs are an enzyme degrading CSPGs in the brain. However, there is a little knowledge regarding ADAMTSs in the CNS. We investigated the expression levels of ADAMTSs mRNAs by RT-PCR after spinal cord injury in mouse. Transcripts encoding 4 of the 19 known ADAMTSs were evaluated in the mouse spinal cord following injury. ADAMTS1, -5 and -9 expression levels were found to be upregulated. No change was observed in ADAMTS4 expression. By means of immunohistochemistry, ADAMTSs were detected in the astrocytes implying its cellular source in SCI. Western blot analyses indicated that aggrecanase-generated proteoglycan fragments are produced after SCI. (c) 2013 Elsevier Ireland Ltd. All rights reserved.
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    ADAMTS4 and ADAMTS5 Knockout Mice Are Protected from Versican but Not Aggrecan or Brevican Proteolysis during Spinal Cord Injury
    (Hindawi Ltd, 2014) Demircan, Kadir; Topcu, Vehap; Takigawa, Tomoyuki; Akyol, Sumeyya; Yonezawa, Tomoko; Ozturk, Gulfer; Ugurcu, Veli
    The chondroitin sulfate proteoglycans (CSPGs) aggrecan, versican, and brevican are large aggregating extracellular matrix molecules that inhibit axonal growth of the mature central nervous system (CNS). ADAMTS proteoglycanases, including ADAMTS4 and ADAMTS5, degrade CSPGs, representing potential targets for ameliorating axonal growth-inhibition by CSPG accumulation after CNS injury. We investigated the proteolysis of CSPGs in mice homozygous for Adamts4 or Adamts5 null alleles after spinal cord injury (SCI). ADAMTS-derived 50-60 kDa aggrecan and 50 kDa brevican fragments were observed in Adamts4-/-, Adamts5-/-, and wt mice but not in the sham-operated group. By contrast Adamts4-/- and Adamts5-/- mice were both protected from versican proteolysis with an ADAMTS-generated 70 kDa versican fragment predominately observed in WT mice. ADAMTS1, ADAMTS9, and ADAMTS15 were detected by Western blot in Adamts4-/- mice' spinal cords after SCI. Immunohistochemistry showed astrocyte accumulation at the injury site. These data indicate that aggrecan and brevican proteolysis is compensated in Adamts4-/- or Adamts5-/- mice by ADAMTS proteoglycanase family members but a threshold of versican proteolysis is sensitive to the loss of a single ADAMTS proteoglycanase during SCI. We show robust ADAMTS activity after SCI and exemplify the requirement for collective proteolysis for effective CSPG clearance during SCI.
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    Early Induction of ADAMTS1,-4,-5 and-9 in IL-Stimulated Mouse Astrocytes
    (Turkish Neurosurgical Soc, 2014) Abali, Osman; Gokce, Emre Cemal; Cemil, Berker; Erdogan, Bulent; Yonezawa, Tomoko; Demircan, Kadir
    AIM: Astrocytes and extracellular matrix molecules have important roles in regulating synaptic functions between neurons in the central nervous system. However, under pathological conditions, these constituents are activated to form glial scar that is thought to be harmful for neuronal regeneration. The aim of this study was to evaluate the expression pattern of ADAMTS1, -4, -5 and -9 in IL-1 stimulated astrocyte cultures obtained from postnatal day zero mouse brains. MATERIAL and METHODS: Real time PCR analyses were performed. RESULTS: An overexpression of ADAMTS1, -4, -5 and -9 at the 3-h time point after IL-1 stimulation was found. IL-1 stimulation induced aggrecaneses and this effect was time dependent. Maximum increase was detected at 3-h (six fold increase). Interestingly the expression of ADAMTS1 and -4 appeared to be at the highest expression level but the ADAMTS5 and ADAMTS9 expression level was much weaker (three times and two times respectively). CONCLUSION:To the best of our knowledge, this is the first report demonstrating induction of ADAMTS in IL-1 induced astrocytes. Aggrecanases may play a role in tissue destruction in the progression of central nervous system (CNS) injury and they are differentially expressed in mouse CNS, suggesting a critical role in the pathogenesis of CNS injury. This can be a very crucial aetiologic factor for some neuropsychiatric disorders.