Animals ; Brain ; embryology ; Ear ; embryology ; Esophagus ; embryology ; Fallopian Tubes ; embryology ; Female ; Heart ; embryology ; Humans ; Kidney ; embryology ; Liver ; embryology ; Lung ; embryology ; Male ; Organogenesis ; physiology ; Penis ; embryology ; Rabbits ; Stomach ; embryology ; Vagina ; embryology

Cells, Cultured ; Cyclic Nucleotide Phosphodiesterases, Type 2 ; antagonists & inhibitors ; metabolism ; Fibroblasts ; drug effects ; metabolism ; Glucosides ; pharmacology ; Humans ; Lung ; cytology ; embryology ; Phenols ; pharmacology ; Phosphodiesterase Inhibitors ; pharmacology ; Tumor Suppressor Protein p53 ; metabolism

OBJECTIVETo predict the target genes of rno-microRNA-296-5p (miR-296) using bioinformatics software and databases, and to provide a theoretical basis for further studies of biological effects of miR-296 in fetal lung development.

METHODSPubMed and Google were used to search for all reported literature on miR-296. The miRBase database was used to determine the sequence and evolutionary conservatism of miR-296. The TargetScans database was used to predict the target genes of miR-296. The DAVID Bioinformatics Resources 6.8 database was used for the functional enrichment analysis of the target genes. The KEGG database was used to analyze the signaling pathways of target genes.

RESULTSmiR-296 was reported to play important roles in many biological processes and have a high degree of sequence conservation among species. The target genes of miR-296 were involved in biological processes, cell components, and molecular function. Those target genes were significantly enriched in the mitogen-activated protein kinase signaling pathway, Wnt signaling pathway, and transforming growth factor-β signaling pathway (p<0.05).

CONCLUSIONSThe bioinformatics analysis of the target genes of miR-296 provides a basis for studying biological effects and mechanism of action of miR-296 in lung development.

Animals ; Computational Biology ; Humans ; Lung ; embryology ; MAP Kinase Signaling System ; physiology ; MicroRNAs ; physiology ; Transforming Growth Factor beta ; physiology ; Wnt Signaling Pathway ; physiology

This study investigated the expression of lung surfactant proteins SP-B and SP-C, and their modulating factors TTF-1 and PLAGL2 in the fetal lung of rats with fetal growth restriction (FGR). The rat FGR model was established by prenatal hypoxia in the first stage of pregnancy, 180 rats for experiment served as hypoxia group, and 197 healthy rats served as normal control group. The FGR incidence in hypoxia was compared with that in normal control group. The histological changes in the fetal lung were observed under the light microscope and electronic microscope in two groups. The SP-B, SP-C, TTF-1 and PLAGL2 proteins were determined in the fetal lung of two groups immunohistochemically. The expression levels of SP-B, SP-C, TTF-1 and PLAGL2 protein and mRNA in the fetal lung of two groups were detected by using Western blotting and RT-PCR respectively. The FGR rat model was successfully established by using hypoxia. Pathologically the fetal lung developed slowly, and the expression levels of SP-B, SP-C, TTF-1 and PLAGL2 protein and mRNA in the fetal lung were significantly reduced in hypoxia group as compared with those in normal control group. It was suggested that maternal hypoxia in the first stage of pregnancy could induce FGR, and reduce the expression of SP-B and SP-C, resulting in the disorder of fetal lung development and maturation.
Animals ; Base Sequence ; DNA Primers ; Female ; Fetal Growth Retardation ; Lung ; embryology ; metabolism ; Peptides ; metabolism ; Pregnancy ; Pulmonary Surfactant-Associated Protein B ; metabolism ; Rats ; Real-Time Polymerase Chain Reaction

OBJECTIVETo bioinformatically predict and analyze target genes of miRNA-126(*), with the aim of providing certain basis for related research about target genes and regulatory mechanism in the future.

METHODSThe miRNA chip technology was applied to measure expression levels of miRNA-126(*) in 3 time points (embryo 16, 19 and 21 days) of fetal lung development. Then the target genes of miRNA-126(*) were screened through miRGen2.0 database. Subsequent bioinformatic analysis of these target genes was performed by Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes Pathway analysis (KEGG Pathway analysis).

RESULTSmiRNA-126(*) manifested continuously upregulated expression with the lung development (from embryo 16 to 21 days). There were 422 predicted target genes in total, and the gene set mainly located in glucuronosyltransferase activity, transferase activity (GO molecular function), multicellular organismal development, developmental process (GO biology process) and intracellular part (GO cellular component). The KEGG Pathway analysis demonstrated that the gene set mostly located in RNA degradation (signal transduction pathway) and prion diseases (disease pathway).

CONCLUSIONSThe results suggest that miRNA-126(*) plays a certain role in fetal lung development and provide a basis for lung development research in the future.

Animals ; Computational Biology ; Female ; Glucuronosyltransferase ; metabolism ; Lung ; embryology ; Male ; MicroRNAs ; physiology ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; physiology

With the advances in pre- and post-natal medical care, the incidence of bronchopulmonary dysplasia (BPD) is on the rise, while its pathogenesis remains not clear. New BPD theory shows that the core pathogenesis of BPD is simple alveolar structure and pulmonary microvascular abnormalities that eventually lead to reduced pulmonary gas exchange, so the research on pulmonary microvascular development was gradually taken seriously. Pulmonary angiogenesis and vascular development require the participation of various cytokines and signaling pathways, the most important of which include VEGF/VEGFR pathway, Ang/Tie pathway, Ephrins/Eph pathway, and Notch/Jagged1 pathway. These cytokines and signaling pathways play important roles in pulmonary vascular development.
Angiopoietins ; physiology ; Blood Vessels ; embryology ; Bronchopulmonary Dysplasia ; etiology ; Cytokines ; physiology ; Ephrins ; physiology ; Humans ; Infant, Newborn ; Lung ; blood supply ; Neovascularization, Physiologic ; Receptors, Notch ; physiology ; Signal Transduction ; physiology ; Vascular Endothelial Growth Factor A ; physiology

OBJECTIVETo investigate the expression and role of miRNA-126/miRNA-126(*) in the fetal lung development of rats.

METHODSTwelve pregnant Sprague-Dawley rats were randomly divided into 3 groups and the fetal rats were removed at 16, 19 and 21 days of gestation respectively. Hematoxylin and eosin staining was performed to observe lung morphology of fetal rats. Then microRNA (miRNA) microarray was used to study the expression patterns of miRNA-126/miRNA-126(*) in fetal lungs at the three time points. And miRNA-126(*) was selected for further study by real-time PCR.

RESULTSThere was no evident difference in the expression of miRNA-126 among the three groups, however the expression level of miRNA-126(*) increased gradually as the fetal lung developed. The real-time PCR result further showed that expression of miRNA-126(*) increased gradually with lung development, displaying significant differences among the three groups (P<0.05).

CONCLUSIONSmiRNA-126(*) may play an important role in development of the fetal lung in rats.

Animals ; Female ; Lung ; embryology ; Male ; MicroRNAs ; analysis ; physiology ; Pregnancy ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction

OBJECTIVETo observe the effects of complement fragment C3f on expression and secretion of collagen I, III and transforming growth factor( TGF)-beta1 in human embryonic lung fibroblast (MRC-5) cells.

METHODSMRC-5 cells were cultured with C3f (the synthetic 17 peptides fragments of complement C3). The extracellular and intracellular expression levels of type I, III collagens and TGF-beta1 in MRC-5 cultures were detected by ELISA and immunohistochemistry, respectively.

RESULTSThe expression levels of type I, III collagen and TGF-beta1 in the supernatant of MRC-5 cultures decreased significantly with the concentrations of C3f as compared with controls (P < 0.05). Also the expression level of TGF-beta1 in MRC-5 cytoplasm reduced significantly as compared with controls (P < 0.05).

CONCLUSIONThe results of present in vitro study showed that the complement fragment C3f could reduce the formation of TGF-beta1 and type I, III collagens in MRC-5 cells, and inhibit the lung tissue fibrosis.

Cell Line ; Collagen Type I ; metabolism ; Collagen Type III ; metabolism ; Complement C3b ; pharmacology ; Fibroblasts ; drug effects ; metabolism ; Humans ; Lung ; cytology ; drug effects ; embryology ; Transforming Growth Factor beta1 ; metabolism

Alveolar type II cells are main target of hyperoxia-induced lung injury. The authors investigated whether lysosomal protease, cathepsin B (CB), is activated in fetal alveolar type II cells in the transitional period from the canalicular to saccular stages during 65%-hyperoxia and whether CB is related to fetal alveolar type II cell (FATIIC) death secondary to hyperoxia. FATIICs were isolated from embryonic day 19 rats and exposed to 65%-oxygen for 24 h and 36 h. The cells exposed to room air were used as controls. Cell cytotoxicity was assessed by lactate dehydrogenase-release and flow cytometry, and apoptosis was analyzed by TUNEL assay and flow cytometry. CB activity was assessed by colorimetric assay, qRT-PCR and western blots. 65%-hyperoxia induced FATIIC death via necrosis and apoptosis. Interestingly, caspase-3 activities were not enhanced in FATIICs during 65%-hyperoxia, whereas CB activities were greatly increased during 65%-hyperoxia in a time-dependent manner, and similar findings were observed with qRT-PCR and western blots. In addition, the preincubation of CB inhibitor prior to 65%-hyperoxia reduced FATIIC death significantly. Our studies suggest that CB activation secondary to hyperoxia might have a relevant role in executing the cell death program in FATIICs during the acute stage of 65%-hyperoxia.
Animals ; Caspase 3 ; Cathepsin B/*metabolism ; Cell Death ; Cell Hypoxia ; Enzyme Activation ; Female ; In Situ Nick-End Labeling ; L-Lactate Dehydrogenase/analysis ; Lung/metabolism ; Necrosis/metabolism ; Oxygen ; Pneumocytes/cytology/*metabolism ; Polymerase Chain Reaction ; Pregnancy ; Pulmonary Alveoli/cytology/embryology/*enzymology ; Rats ; Rats, Sprague-Dawley

OBJECTIVECyclinD1 and p21CIP1 are major proteins to regulate lung cell proliferation and involved in lung development and lung injury reparation. This study aimed to explore the expression manners of CyclinD1 and p21CIP1 at canalicular, saccular and alveolar stages during lung development in Sprague-Dawley rats.

METHODSLung tissues were obtained from fetal rats of 20 and 21 days gestational ages, and neonatal rats at 0, 3, 7, 14 and 21 days (n=6). Lung tissues were used for histopathology and the protein analysis of CyclinD1 and p21CIP1 (immunohistochemistry and Western blot).

RESULTSThe strongest expression of CyclinD1 and the weakest expression of p21CIP1 occurred at 20-21 days gestation (canalicular stage). At the canalicular stage, CyclinD1 was mainly expressed in epithelial cells, and the expression of p21CIP1was negative. At the saccular stage, the expression of CyclinD1 decreased significantly and the p21CIP1 expression increased significantly. Positive expression of CyclinD1 and p21CIP1 was found in epithelial cells and interstitial cells. At the alveolar stage, the CyclinD1 expression was the lowest and the p21CIP1 expression was the highest. The positive expression of CyclinD1 was found in interstitial cells and that of p21CIP1 was found in epithelial cells.

CONCLUSIONSThe location and quantity of CyclinD1 and p21CIP1 expression are different at various stages during lung development in rats. A strongest CyclinD1 expression found in the canalicular stage may be associated a high lung cell proliferation. A strongest p21CIP1 expression found in the alveolar stage may be associated with alveolar maturity.

Animals ; Blotting, Western ; Cyclin D1 ; analysis ; Cyclin-Dependent Kinase Inhibitor p21 ; analysis ; Female ; Immunohistochemistry ; Lung ; chemistry ; embryology ; Male ; Rats ; Rats, Sprague-Dawley