title: Leptin enhances lung maturity in the fetal rat.
abstract: Pulmonary alveolar type II cells synthesize and secrete phospholipids and surfactant proteins. In most mammalian species, the synthesis of phospholipids and proteins of lung surfactant increases with fetal lung maturation, which occurs late in gestation. Factors that may promote lung maturation and surfactant production include the placental hormone, leptin, whose expression increases with advancing gestational age. We demonstrate that physiologic concentrations of leptin (1 and 10 ng/mL) increase the levels of surfactant proteins (SP) A, B, and C mRNA as well as SP-A and SP-B protein in d-17 fetal rat lung explants in vitro. To determine whether leptin exerts similar effects in vivo, we administered leptin antenatally to pregnant rats and compared its effects to that of dexamethasone, a known mediator of fetal lung development. Antenatal treatment with leptin for 2 d significantly increased the average weight of the fetal lungs in relation to their body weight. Histologic analysis revealed that the increase in fetal lung weight was accompanied by an increase in the number and maturation of type II alveolar cells and the expression of surfactant proteins B and C in these cells. Collectively, these results suggest that leptin is a cytokine regulator of rat fetal lung maturity.
authors.affiliation: Department of Biomedical Research and Pediatrics, Alfred I. duPont Hospital for Children/Nemours Children's Clinic, Delaware 19803, USA.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Kirwin
authors.forename: Vineet
authors.initials: V
authors.lastname: Bhandari
authors.forename: Darlise
authors.initials: D
authors.lastname: Dimatteo
authors.forename: Carol
authors.initials: C
authors.lastname: Barone
authors.forename: Linda
authors.initials: L
authors.lastname: Johnson
authors.forename: Saptarashi
authors.initials: S
authors.lastname: Paul
authors.forename: Alan R
authors.initials: AR
authors.lastname: Spitzer
authors.forename: Avinash
authors.initials: A
authors.lastname: Chander
authors.forename: Sandra G
authors.initials: SG
authors.lastname: Hassink
authors.forename: Vicky L
authors.initials: VL
authors.lastname: Funanage
mesh_terms: D000818:Animals; D005260:Female; D047109:Fetal Development / Q000187:drug effects* / Q000502:physiology; D005333:Fetus / Q000737:chemistry / Q000187:drug effects* / Q000502:physiology; D020738:Leptin / Q000494:pharmacology* / Q000502:physiology; D008168:Lung / Q000254:growth & development*; D011247:Pregnancy; D037661:Pulmonary Surfactant-Associated Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D020738:Leptin; D037661:Pulmonary Surfactant-Associated Proteins; D012333:RNA, Messenger