title: Tanshinone IIA pretreatment renders free flaps against hypoxic injury through activating Wnt signaling and upregulating stem cell-related biomarkers.
abstract: Partial or total flap necrosis after flap transplantation is sometimes clinically encountered in reconstructive surgery, often as a result of a period of hypoxia that exceeds the tolerance of the flap tissue. In this study, we determine whether tanshinone IIA (TSA) pretreatment can protect flap tissue against hypoxic injury and improve its viability. Primary epithelial cells isolated from the dorsal skin of mice were pretreated with TSA for two weeks. Cell counting kit-8 and Trypan Blue assays were carried out to examine the proliferation of TSA-pretreated cells after exposure to cobalt chloride. Then, Polymerase chain reaction and Western blot analysis were used to determine the expression of β-catenin, GSK-3β, SOX2, and OCT4 in TSA-treated cells. In vivo, after mice were pretreated with TSA for two weeks, a reproducible ischemic flap model was implemented, and the area of surviving tissue in the transplanted flaps was measured. Immunohistochemistry was also conducted to examine the related biomarkers mentioned above. Results show that epidermal cells, pretreated with TSA, showed enhanced resistance to hypoxia. Activation of the Wnt signaling pathway in TSA-pretreated cells was characterized by the upregulation of β-catenin and the downregulation of GSK-3β. The expression of SOX2 and OCT4 controlled by Wnt signaling were also found higher in TSA pretreated epithelial cells. In the reproducible ischaemic flap model, pretreatment with TSA enhanced resistance to hypoxia and increased the area of surviving tissue in transplanted flaps. The expression of Wnt signaling pathway components, stem-cell related biomarkers, and CD34, which are involved in the regeneration of blood vessels, was also upregulated in TSA-pretreated flap tissue. The results show that TSA pretreatment protects free flaps against hypoxic injury and increases the area of surviving tissue by activating Wnt signaling and upregulating stem cell-related biomarkers.
authors.affiliation: Department of Burns and Plastic Surgery, Shaanxi Provincial People's Hospital, Xi'an 710068, China. xuzihan0925@163.com.
authors.forename: Zihan
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Department of Burns and Plastic Surgery, Shaanxi Provincial People's Hospital, Xi'an 710068, China. zzsxa2006@163.com.
authors.forename: Zhenxin
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Plastic Surgery, the Second Affiliated Hospital of Soochow University, Suzhou 215004, China. ljwu1986@163.com.
authors.forename: Lijun
authors.initials: L
authors.lastname: Wu
authors.affiliation: Department of Burns and Plastic Surgery, Shaanxi Provincial People's Hospital, Xi'an 710068, China. sunyaowen888@163.com.
authors.forename: Yaowen
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Burns and Plastic Surgery, Shaanxi Provincial People's Hospital, Xi'an 710068, China. yadongg2000@163.com.
authors.forename: Yadong
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Department of Burns and Plastic Surgery, Shaanxi Provincial People's Hospital, Xi'an 710068, China. qingaoping@163.com.
authors.forename: Gaoping
authors.initials: G
authors.lastname: Qin
authors.affiliation: Department of Burns and Plastic Surgery, Shaanxi Provincial People's Hospital, Xi'an 710068, China. mszping@163.com.
authors.forename: Shengzhi
authors.initials: S
authors.lastname: Mu
authors.affiliation: Department of Burns and Plastic Surgery, Shaanxi Provincial People's Hospital, Xi'an 710068, China. doctorfanronghui@163.com.
authors.forename: Ronghui
authors.initials: R
authors.lastname: Fan
authors.affiliation: Department of Burns and Plastic Surgery, Shaanxi Provincial People's Hospital, Xi'an 710068, China. wangben.369@163.com.
authors.forename: Benfeng
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Burns and Plastic Surgery, Shaanxi Provincial People's Hospital, Xi'an 710068, China. xuesonggaowenjie@163.com.
authors.forename: Wenjie
authors.initials: W
authors.lastname: Gao
mesh_terms: D045784:Abietanes / Q000494:pharmacology*; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D015687:Cell Hypoxia; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D003035:Cobalt / Q000494:pharmacology; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects* / Q000378:metabolism; D058752:Free Tissue Flaps; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism; D000071679:Glycogen Synthase Kinase 3 beta; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D050814:Octamer Transcription Factor-3 / Q000378:metabolism; D055748:SOXB1 Transcription Factors / Q000378:metabolism; D012867:Skin / Q000378:metabolism / Q000473:pathology; D016378:Tissue Transplantation; D015854:Up-Regulation / Q000187:drug effects*; D060449:Wnt Signaling Pathway / Q000187:drug effects*; D051176:beta Catenin / Q000378:metabolism
chemical_list: D045784:Abietanes; D015415:Biomarkers; D050814:Octamer Transcription Factor-3; C494174:Pou5f1 protein, mouse; D055748:SOXB1 Transcription Factors; C527783:Sox2 protein, mouse; D051176:beta Catenin; C021751:tanshinone; D003035:Cobalt; D000071679:Glycogen Synthase Kinase 3 beta; C000605507:Gsk3b protein, mouse; D038362:Glycogen Synthase Kinase 3; C018021:cobaltous chloride