title: Active hyaluronidase 2 expression in the granulation tissue formed in the healing process of equine superficial digital flexor tendonitis.
abstract: Upregulation of hyaluronidase 2 (HYAL2), one of somatic hyaluronidase (HAase), was demonstrated in granulation tissue during the healing of equine superficial digital flexor tendon injuries. The activity of HAase was assessed by hyaluronan (HA)-containing gel zymography and in situ zymography using frozen sections obtained from normal and injured tendon tissues. Elevated HAase activity was identified in the extract from the tendinopathic tissues, with lower levels of the activity in normal tendons. In situ zymography using fluorescently-labeled HA demonstrated HAase activity in the granulation tissue formed in the injured region. In addition, in situ hybridization analysis indicated that fibroblastic cells in the granulation tissue of the injured tendon actively expressed HYAL2 but not HYAL1. Quantitative RT-PCR further confirmed a higher level of amplicons corresponding to HYAL2 in tendonitis-derived samples. These results suggest that elevated HYAL2 activity in the granulation tissue could participate in controlling the healing process in equine tendonitis.
authors.affiliation: Department of Tissue Physiology, Tokyo University of Agriculture and Technology, Tokyo, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Yuda
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kasashima
authors.forename: Atsutoshi
authors.initials: A
authors.lastname: Kuwano
authors.forename: Kan
authors.initials: K
authors.lastname: Sato
authors.forename: Shunji
authors.initials: S
authors.lastname: Hattori
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Arai
mesh_terms: D000818:Animals; D005552:Forelimb; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D006097:Granulation Tissue / Q000201:enzymology* / Q000378:metabolism; D006734:Horse Diseases / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D006736:Horses; D006821:Hyaluronoglucosaminidase / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008297:Male; D052256:Tendinopathy / Q000201:enzymology / Q000235:genetics / Q000378:metabolism / Q000662:veterinary*; D015854:Up-Regulation
chemical_list: D006821:Hyaluronoglucosaminidase