title: Leptin accelerates enterocyte turnover during methotrexate-induced intestinal mucositis in a rat.
abstract: Gastrointestinal mucositis occurs as a consequence of cytotoxic treatment. In the present study, we tested whether leptin can protect gut epithelial cells from methotrexate (MTX)-induced intestinal damage. Non-pretreated and pretreated with MTX Caco-2 cells were incubated with increasing concentrations of leptin for 24 h. Cell proliferation and apoptosis were assessed using FACS analysis. Adult rats were divided into three experimental groups: Control rats; MTX-rats were treated with a single dose of MTX, and MTX-LEP rats were also treated with leptin for 3 d. Intestinal mucosal damage (Park score), mucosal structural changes (bowel and mucosal weight, mucosal DNA and protein content, villus height and crypt depth), enterocyte proliferation, and enterocyte apoptosis were measured at sacrifice. RT-PCR was used to determine the level of bax and bcl-2 mRNA expression. In the vitro experiment, treatment with leptin of Caco-2 cells pre-treated with MTX resulted in a significant stimulation of cell proliferation and inhibition of cell apoptosis in a dose-dependent manner. In the vivo experiment, MTX-LEP rats demonstrated a greater jejunal and ileal bowel and mucosal weight, mucosal DNA and protein, villus height and crypt depth, as well as a greater enterocyte proliferation index compared to MTX-animals. MTX-LEP rats also showed a trend toward an increase in enterocyte apoptosis that was accompanied by an increase in bax mRNA and decrease in bcl-2 mRNA expression. In conclusion, leptin enhances proliferation and decreases apoptosis in Caco-2 cells pretreated with MTX. In a rat model of MTX-induced mucositis, treatment with leptin improves intestinal recovery and enhances enterocyte turnover.
authors.affiliation: The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Laboratory of intestinal adaptation and recovery, Bnai Zion Medical Center, Haifa, Israel. igor-dr@internet-zahav.net
authors.forename: Igor
authors.initials: I
authors.lastname: Sukhotnik
authors.forename: Jorge G
authors.initials: JG
authors.lastname: Mogilner
authors.forename: Dan
authors.initials: D
authors.lastname: Shteinberg
authors.forename: Rahel
authors.initials: R
authors.lastname: Karry
authors.forename: Michael
authors.initials: M
authors.lastname: Lurie
authors.forename: Benno M
authors.initials: BM
authors.lastname: Ure
authors.forename: Ron
authors.initials: R
authors.lastname: Shaoul
authors.forename: Arnold G
authors.initials: AG
authors.lastname: Coran
mesh_terms: D000818:Animals; D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D018938:Caco-2 Cells; D049109:Cell Proliferation / Q000187:drug effects; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D020895:Enterocytes / Q000378:metabolism* / Q000502:physiology; D016650:Fluorescein-5-isothiocyanate / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D006801:Humans; D007082:Ileum / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007583:Jejunum / Q000378:metabolism; D020738:Leptin / Q000494:pharmacology*; D008297:Male; D008727:Methotrexate / Q000009:adverse effects; D052016:Mucositis / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function; D013997:Time Factors; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D017304:Annexin A5; D005456:Fluorescent Dyes; D020738:Leptin; D012333:RNA, Messenger; D051028:bcl-2-Associated X Protein; D016650:Fluorescein-5-isothiocyanate; D008727:Methotrexate