title: Retinoic acid regulation of renal tubular epithelial and vascular smooth muscle cell function.
abstract: Vitamin A and its derivatives have been postulated to play an important role in renal tubulogenesis and compensatory hypertrophy. This study examined the effects of two carboxylic derivatives of vitamin A on Lewis lung carcinoma-porcine kidney-1 (LLC-PK1) renal tubular epithelial cell mito- and motogenesis and cell size. It was found that all-trans and 13-cis retinoic acids exerted modest, dose-dependent effects to stimulate incorporation of 3H-thymidine into acid-precipitable material of LLC-PK1 cells. The effects of all-trans retinoic acid to promote 3H-thymidine uptake in LLC-PK1 cells modestly enhanced that seen with acidic fibroblastic growth factor. Similar findings of these two retinoic acid derivatives to promote 3H-thymidine uptake and to enhance 3H-thymidine uptake stimulated by another growth factor (platelet-derived growth factor BB) were also observed in cultured bovine aortic smooth muscle cells. Both retinoic acids promoted healing of denuded areas made within confluent monolayers of serum-starved LLC-PK1 cells. All-trans retinoic acid also stimulated recovery of mechanically denuded areas within bovine aortic smooth muscle monolayers. Neither all-trans nor 13-cis retinoic acids s affected cell size as assessed by forward light scatter with flow cytometry, suggesting lack of effect to induce hypertrophy. These results demonstrate that two carboxylic acid derivatives of vitamin A are capable of stimulation of basal and growth factor-induced incorporation of 3H-thymidine uptake into acid-precipitable material and healing of denuded areas in disparate cell types. These findings are compatible with a role for vitamin A and its analogues in the tissue repair process.
authors.affiliation: Denver Veterans Affairs Medical Center and Department of Medicine, University of Colorado Health Sciences Center, 80262, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Anderson
authors.forename: C J
authors.initials: CJ
authors.lastname: Ray
authors.forename: B G
authors.initials: BG
authors.lastname: Hattler
mesh_terms: D000818:Animals; D000077214:Becaplermin; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects / Q000502:physiology; D016220:Fibroblast Growth Factor 1 / Q000494:pharmacology; D015474:Isotretinoin / Q000494:pharmacology*; D007684:Kidney Tubules / Q000166:cytology / Q000187:drug effects*; D018374:LLC-PK1 Cells; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D020574:Proto-Oncogene Proteins c-sis; D013552:Swine; D013936:Thymidine / Q000493:pharmacokinetics; D014212:Tretinoin / Q000494:pharmacology*; D014945:Wound Healing / Q000187:drug effects
chemical_list: D010982:Platelet-Derived Growth Factor; D020574:Proto-Oncogene Proteins c-sis; D016220:Fibroblast Growth Factor 1; D000077214:Becaplermin; D014212:Tretinoin; D015474:Isotretinoin; D013936:Thymidine