title: Twist relates to tubular epithelial-mesenchymal transition and interstitial fibrogenesis in the obstructed kidney.
abstract: Epithelial-mesenchymal transition (EMT) is a critical step in renal fibrosis. It has been recently reported that a transcription factor, Twist, plays a pivotal role in metastasis of breast tumors by inducing EMT. In this study, we examined whether Twist relates to renal fibrogenesis including EMT of tubular epithelia, evaluating Twist expression level in the unilateral ureteral obstruction (UUO) model. Kidneys of mice subjected to UUO were harvested 1, 3, 7, and 10 days after obstruction. Compared with control kidneys, Twist mRNA-level significantly increased 3 days after UUO (UUO day 3 kidney) and further augmented until 10 days after UUO. Twist expression increased in tubular epithelia of the dilated tubules and the expanded interstitial areas of UUO kidneys, where cell-proliferating appearances were frequently found in a time-dependent manner. Although a part of tubular cells in whole nephron segment were immunopositive for Twist in UUO day 7 kidneys, tubular epithelia downstream of nephron more frequently expressed Twist than upstream of nephron. In UUO day 7 kidneys, some tubular epithelia were confirmed to coexpress Twist and fibroblast-specific protein-1, a marker for EMT, indicating that Twist is involved in tubular EMT under pathological state. Twist was expressed also in a number of alpha-smooth muscle actin-positive myofibroblasts located in the expanded interstitial area of UUO kidneys. From these findings, the present investigation suggests that Twist is associated with tubular EMT, proliferation of myofibroblasts, and subsequent renal fibrosis in obstructed kidneys.
authors.affiliation: Department of Anatomy II, School of Dental Medicine, Tsurumi University, Yokohama, 230-8501, Japan.
authors.forename: Yujiro
authors.initials: Y
authors.lastname: Kida
authors.forename: Kinji
authors.initials: K
authors.lastname: Asahina
authors.forename: Hirobumi
authors.initials: H
authors.lastname: Teraoka
authors.forename: Inna
authors.initials: I
authors.lastname: Gitelman
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Sato
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis; D049109:Cell Proliferation; D004847:Epithelial Cells / Q000473:pathology*; D005355:Fibrosis; D007150:Immunohistochemistry; D007668:Kidney / Q000378:metabolism / Q000473:pathology*; D007684:Kidney Tubules / Q000378:metabolism / Q000473:pathology; D008297:Male; D008648:Mesoderm / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000096:biosynthesis; D013997:Time Factors; D051879:Twist-Related Protein 1 / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D014517:Ureteral Obstruction / Q000378:metabolism*; D051154:Wnt2 Protein / Q000096:biosynthesis / Q000235:genetics
chemical_list: D015415:Biomarkers; D012333:RNA, Messenger; D051879:Twist-Related Protein 1; D051154:Wnt2 Protein