title: Hyperthermia exacerbates the effects of cathepsin L on claudin-1 in a blood-brain barrier model in vitro.
abstract: OBJECTIVE
  The effects of cathepsin L on claudin-1 expression were investigated under hyperthermic condition in a blood-brain barrier (BBB) model in vitro, in order to estimate the potential effects of hyperthermia on BBB dysfunction.
  
  
  METHODS
  Brain microvascular endothelial cells (BMECs) and astrocytes were obtained from rat brain. The BBB models were randomly divided into a sham (37°C) group, a 39°C group, a 37°C+cathepsin L group and a 39°C+cathepsin L group. The permeability of BBB was judged. The expressions of cathepsin L in astrocytes and claudin-1 in BMECs were detected using immunohistochemistry method and western blot assay.
  
  
  RESULTS
  The permeability of BBB models was higher in the 39°C group than in the sham group. The cathepsin L expression in astrocytes was higher in the 39°C group than in the sham group (P<0.01), whereas the claudin-1 expression in BMECs was lower in the 39°C group than in the sham group (P<0.01). The claudin-1 expression in BMECs was significantly lower in the 37°C+cathepsin L group than in the sham group (P<0.01). At the same time point, the claudin-1 expression in BMECs was significantly lower in the 39°C+cathepsin L group than in the 37°C+cathepsin L group (P<0.01).
  
  
  CONCLUSIONS
  Hyperthermia can probably decrease claudin-1 expression in BMECs by upregulating cathepsin L expression in astrocytes in a BBB model in vitro.
authors.affiliation: Department of Postgraduate, Kunming Medical University, Kunming, Yunnan, China.
authors.forename: Conghua
authors.initials: C
authors.lastname: Ji
authors.affiliation: Department of Postgraduate, Kunming Medical University, Kunming, Yunnan, China.
authors.forename: Limin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Clinical Laboratory, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China.
authors.forename: Rongrong
authors.initials: R
authors.lastname: Dai
authors.affiliation: Department of Postgraduate, Kunming Medical University, Kunming, Yunnan, China.
authors.forename: Li
authors.initials: L
authors.lastname: Shan
authors.affiliation: Department of Pathology, the First People's Hospital of Yunnan Province, Kunming, Yunnan, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Clinical Laboratory, the Affiliated Kunhua Hospital of Kunming University of Science and Technology, Kunming, Yunnan, China.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Department of Neurology, the First People's Hospital of Yunnan Province, Kunming, Yunnan, China. Electronic address: mq301@sina.com.cn.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Meng
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism; D001692:Biological Transport / Q000187:drug effects; D001812:Blood-Brain Barrier / Q000187:drug effects* / Q000378:metabolism*; D001921:Brain / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism; D056668:Cathepsin L / Q000378:metabolism / Q000494:pharmacology*; D002463:Cell Membrane Permeability; D062445:Claudin-1 / Q000096:biosynthesis*; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D005334:Fever / Q000378:metabolism*; D006979:Hyperthermia, Induced / Q000379:methods; D066298:In Vitro Techniques; D055806:Microvessels; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D015854:Up-Regulation
chemical_list: D062445:Claudin-1; D056668:Cathepsin L
keywords: Astrocytes; Blood-brain barrier; Brain microvascular endothelial cells; Cathepsin L; Claudin-1; Hyperthermia