Animals ; Cdc20 Proteins/metabolism* ; Cell Line ; Embryo, Mammalian/embryology* ; Embryonic Development ; Female ; Infertility, Female/metabolism* ; Mice ; Mutation ; Oocytes/metabolism*

Understanding limb development not only gives insights into the outgrowth and differentiation of the limb, but also has clinical relevance. Limb development begins with two paired limb buds (forelimb and hindlimb buds), which are initially undifferentiated mesenchymal cells tipped with a thickening of the ectoderm, termed the apical ectodermal ridge (AER). As a transitional embryonic structure, the AER undergoes four stages and contributes to multiple axes of limb development through the coordination of signalling centres, feedback loops, and other cell activities by secretory signalling and the activation of gene expression. Within the scope of proximodistal patterning, it is understood that while fibroblast growth factors (FGFs) function sequentially over time as primary components of the AER signalling process, there is still no consensus on models that would explain proximodistal patterning itself. In anteroposterior patterning, the AER has a dual-direction regulation by which it promotes the sonic hedgehog (Shh) gene expression in the zone of polarizing activity (ZPA) for proliferation, and inhibits Shh expression in the anterior mesenchyme. In dorsoventral patterning, the AER activates Engrailed-1 (En1) expression, and thus represses Wnt family member 7a (Wnt7a) expression in the ventral ectoderm by the expression of Fgfs, Sp6/8, and bone morphogenetic protein (Bmp) genes. The AER also plays a vital role in shaping the individual digits, since levels of Fgf4/8 and Bmps expressed in the AER affect digit patterning by controlling apoptosis. In summary, the knowledge of crosstalk within AER among the three main axes is essential to understand limb growth and pattern formation, as the development of its areas proceeds simultaneously.
Animals ; Apoptosis ; Body Patterning ; Bone Morphogenetic Proteins/biosynthesis* ; Developmental Biology ; Ectoderm/metabolism* ; Extremities/embryology* ; Fibroblast Growth Factor 10/metabolism* ; Fibroblast Growth Factors/biosynthesis* ; Gene Expression Regulation ; Hedgehog Proteins/biosynthesis* ; Homeodomain Proteins/biosynthesis* ; Mesoderm/metabolism* ; Mice ; Signal Transduction ; Wnt Proteins/biosynthesis*

Diffuse intrinsic pontine glioma (DIPG) is the main cause of brain tumor-related death among children. Until now, there is still a lack of effective therapy with prolonged overall survival for this disease. A typical strategy for preclinical cancer research is to find out the molecular differences between tumor tissue and para-tumor normal tissue, in order to identify potential therapeutic targets. Unfortunately, it is impossible to obtain normal tissue for DIPG because of the vital functions of the pons. Here we report the human fetal hindbrain-derived neural progenitor cells (pontine progenitor cells, PPCs) as normal control cells for DIPG. The PPCs not only harbored similar cell biological and molecular signatures as DIPG glioma stem cells, but also had the potential to be immortalized by the DIPG-specific mutation H3K27M in vitro. These findings provide researchers with a candidate normal control and a potential medicine carrier for preclinical research on DIPG.
Animals ; Brain Stem Neoplasms ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; Cellular Senescence ; Female ; Glioma ; genetics ; metabolism ; pathology ; Histones ; genetics ; Humans ; Mice, Inbred NOD ; Mice, SCID ; Neoplasm Transplantation ; Neoplastic Stem Cells ; drug effects ; metabolism ; pathology ; Neural Stem Cells ; drug effects ; metabolism ; pathology ; Pons ; embryology ; metabolism ; pathology ; Primary Cell Culture

OBJECTIVE: : To observe the expression of gene in the early development stage of wild zebrafish embryos. METHODS: : The collinearity of gene and the sequence similarity of G6pd protein were analyzed with gene database and BLAST software, respectively. Expression of gene in different development stages of zebrafish embryos was detected by hybridization. The -EGFP-pCS recombinant plasmids were microinjected into zebrafish embryos, and fluorescence was observed under a fluorescence microscope. The expression of G6pd protein at 24, 48 and 72 hour post fertilization (hpf) zebrafish embryos was detected by Western blotting; the enzyme activity of G6pd at 24, 48 and 72 hpf zebrafish embryos was detected by modified G6pd quantitative ratio method. RESULTS: : The G6pd protein similarity of zebrafish and human was 88%, and that of zebrafish and mouse was 87%. The results of hybridization showed that the gene was mainly expressed in the hematopoietic tissues of zebrafish; the results observed after microinjection of -EGFP-pCS recombinant plasmid were consistent with the results of hybridization. At 24, 48 and 72 hpf, the relative expression levels of G6pd protein in zebrafish embryos were 1.44±0.03, 1.47±0.05, and 1.54±0.02, respectively(>0.05); the G6pd enzyme activity levels were 1.74±0.17, 1.75±0.12, 1.71±0.22, respectively (>0.05). CONCLUSIONS : The study has observed the expression of gene and G6pd protein, and G6pd enzyme activity in zebrafish embryos at different development phases, which provides a reference for the establishment of a zebrafish G6PD deficiency model.
Animals ; Embryo, Nonmammalian ; Gene Expression Regulation, Developmental ; Glucosephosphate Dehydrogenase ; genetics ; Humans ; In Situ Hybridization ; Mice ; Plasmids ; genetics ; Zebrafish ; embryology ; genetics

Background: Valproic acid (VPA) exposure during pregnancy has been proven to contribute to congenital heart disease (CHD). Our previous findings implied that disruption of planar cell polarity (PCP) signaling pathway in cardiomyocytes might be a factor for the cardiac teratogenesis of VPA. In addition, the teratogenic ability of VPA is positively correlated to its histone deacetylase (HDAC) inhibition activity. This study aimed to investigate the effect of the VPA on cardiac morphogenesis, HDAC1/2/3, and PCP key genes (Vangl2/Scrib/Rac1), subsequently screening out the specific HDACs regulating PCP pathway. Methods: VPA was administered to pregnant C57BL mice at 700 mg/kg intraperitoneally on embryonic day 10.5. Dams were sacrificed on E15.5, and death/absorption rates of embryos were evaluated. Embryonic hearts were observed by hematoxylin-eosin staining to identify cardiac abnormalities. H9C2 cells (undifferentiated rat cardiomyoblasts) were transfected with Hdac1/2/3 specific small interfering RNA (siRNA). Based on the results of siRNA transfection, cells were transfected with Hdac3 expression plasmid and subsequently mock-treated or treated with 8.0 mmol/L VPA. Hdac1/2/3 as well as Vangl2/Scrib/Rac1 mRNA and protein levels were determined by real-time quantitative polymerase chain reaction and Western blotting, respectively. Total HDAC activity was detected by colorimetric assay. Results: VPA could induce CHD (P < 0.001) and inhibit mRNA or protein expression of Hdac1/2/3 as well as Vangl2/Scrib in fetal hearts, in association with total Hdac activity repression (all P < 0.05). In vitro, Hdac3 inhibition could significantly decrease Vangl2/Scrib expression (P < 0.01), while knockdown of Hdac1/2 had no influence (P > 0.05); VPA exposure dramatically decreased the expression of Vanlg2/Scrib together with Hdac activity (P < 0.01), while overexpression of Hdac3 could rescue the VPA-induced inhibition (P > 0.05). Conclusion VPA could inhibit Hdac1/2/3, Vangl2/Scrib, or total Hdac activity both in vitro and in vivo and Hdac3 might participate in the process of VPA-induced cardiac developmental anomalies.
Animals ; Cell Polarity ; Enzyme Inhibitors ; adverse effects ; Female ; Fetal Heart ; embryology ; Heart Defects, Congenital ; chemically induced ; physiopathology ; Histone Deacetylase Inhibitors ; Histone Deacetylases ; drug effects ; physiology ; Mice ; Mice, Inbred C57BL ; Nerve Tissue Proteins ; Pregnancy ; Rats ; Transfection ; Valproic Acid ; adverse effects

OBJECTIVE: In vitro culture of preimplantation embryos is improved by grouping embryos together in a drop of media. Individually cultured embryos are deprived of paracrine factors; with this in mind, we investigated whether the addition of a single embryo-secreted factor, interleukin-6 (IL-6), could improve the development of individually cultured embryos. METHODS: Mouse embryos were cultured individually in 2 µL of G1/G2 media in 5% oxygen and supplemented with a range of doses of recombinant mouse or human IL-6. RESULTS: Mouse IL-6 increased hatching at doses of 0.01 and 10 ng/mL compared to the control (93% and 93% vs. 78%, p<0.05) and increased the total number of cells at a dose of 0.1 ng/mL compared to the control (101.95±3.36 vs. 91.31±3.33, p<0.05). In contrast, the highest dose of 100 ng/mL reduced the total number of cells (79.86±3.29, p<0.05). Supplementation with human IL-6 had a different effect, with no change in hatching or total cell numbers, but an increase in the percentage of inner cell mass per embryo at doses of 0.1, 1, and 100 ng/mL compared to the control (22.9%±1.1%, 23.3%±1.1%, and 23.1%±1.1% vs. 19.5%±1.0%, p<0.05). CONCLUSION: These data show that IL-6 improved mouse embryo development when cultured individually in complex media; however, an excess of IL-6 may be detrimental. Additionally, these data indicate that there is some cross-species benefit of human IL-6 for mouse embryos, but possibly through a different mechanism than for mouse IL-6.
Animals ; Blastocyst* ; Cell Count* ; Culture Media ; Cytokines ; Embryology ; Embryonic Development ; Embryonic Structures* ; Female ; Fertilization in Vitro ; Humans ; In Vitro Techniques ; Interleukin-6* ; Mice* ; Oxygen ; Pregnancy

OBJECTIVEThis study aimed to investigate the expression pattern and function of Nuclear receptor subfamily 2 group E member 1 (Nr2e1) in retinoic acid (RA)-induced brain abnormality.

METHODSThe mouse model of brain abnormality was established by administering 28 mg/kg RA, and neural stem cells (NSCs) were isolated from the mouse embryo and cultured in vitro. Nr2e1 expression was detected by whole mount in situ hybridization, RT-PCR, and Western blotting. Nr2e1 function was determined by transducing Nr2e1 shRNA into NSCs, and the effect on the sonic hedgehog (Shh) signaling pathway was assessed in the cells. In addition, the regulation of Nr2e1 expression by RA was also determined in vitro.

RESULTSNr2e1 expression was significantly downregulated in the brain and NSCs of RA-treated mouse embryos, and knockdown of Nr2e1 affected the proliferation of NSCs in vitro. In addition, a similar expression pattern of Nr2e1 and RA receptor (RAR) α was observed after treatment of NSCs with different concentrations of RA.

CONCLUSIONOur study demonstrated that Nr2e1 could be regulated by RA, which would aid a better understanding of the mechanism underlying RA-induced brain abnormality.

Animals ; Brain ; cytology ; embryology ; Cell Proliferation ; Down-Regulation ; Gene Expression Regulation ; Gene Expression Regulation, Developmental ; drug effects ; Mice ; Mice, Inbred C57BL ; Neural Stem Cells ; drug effects ; physiology ; Receptors, Cytoplasmic and Nuclear ; genetics ; metabolism ; Tretinoin ; pharmacology

We used Smo siRNA to inhibit hedgehog signaling pathway in embryonic day (E) 13 palatal shelves in organ culture. SiRNA 4 was chosen as the most efficient from four synthesized Smo siRNAs. Palatal shelf fusion rate of 4 μg/mL cyclopamine group was the lowest and significantly lower than that of blank control group (P<0.05), and that of siRNA 4 group was also lower than that of blank control group (P=0.183). At 48 h after transfection, Smo protein level of siRNA 4 group was 64.8% lower than that of blank control group (P<0.05), and Gli1 protein level of 4 μg/mL cyclopamine group was 68.9% lower than that of blank control group (P<0.05). Hedgehog signaling pathway inhibition decreased palatal fusion in organ culture, probably owing to downregulation of Smo and Gli1 proteins.
Animals ; Hedgehog Proteins ; genetics ; metabolism ; Kruppel-Like Transcription Factors ; genetics ; metabolism ; Mice ; Nerve Tissue Proteins ; genetics ; metabolism ; Palate ; embryology ; metabolism ; RNA, Small Interfering ; genetics ; metabolism ; Signal Transduction ; Zinc Finger Protein Gli2 ; Zinc Finger Protein Gli3

The milk fat globule-EGF-factor 8 protein (MFG-E8) has been identified in various tissues, where it has an important role in intercellular interactions, cellular migration, and neovascularization. Previous studies showed that MFG-E8 is expressed in different cell types under normal and pathophysiological conditions, but its expression in hematopoietic stem cells (HSCs) during hematopoiesis has not been reported. In the present study, we investigated MFG-E8 expression in multiple hematopoietic tissues at different stages of mouse embryogenesis. Using immunohistochemistry, we showed that MFG-E8 was specifically expressed in CD34+ HSCs at all hematopoietic sites, including the yolk sac, aorta-gonad-mesonephros region, placenta and fetal liver, during embryogenesis. Fluorescence-activated cell sorting and polymerase chain reaction analyses demonstrated that CD34+ cells, purified from the fetal liver, expressed additional HSC markers, c-Kit and Sca-1, and that these CD34+ cells, but not CD34- cells, highly expressed MFG-E8. We also found that MFG-E8 was not expressed in HSCs in adult mouse bone marrow, and that its expression was confined to F4/80+ macrophages. Together, this study demonstrates, for the first time, that MFG-8 is expressed in fetal HSC populations, and that MFG-E8 may have a role in embryonic hematopoiesis.
Animals ; Antigens, CD34/analysis ; Antigens, Surface/*analysis ; Bone Marrow/ultrastructure ; Female ; Hematopoietic Stem Cells/*cytology ; Liver/embryology ; Mice/*embryology ; Milk Proteins/*analysis ; Placentation ; Pregnancy

OBJECTIVEThe glucocorticoid dexamethasone (DEX) can induce palatal cleft; however, the mechanism involved remains unclear. E-cadherin is an important cell adhesion molecule, and it can significantly affect cell fate and embryonic development. Recent studies have indicated that E-cadherin expression in palatal epithelial cells is suppressed in normal palate fusion. This study aimed to determine whether the change in E-cadherin expression is related to the incidence of cleft palate in DEX-induced mice.

METHODSMice were divided into the experimental group and the control group. Pregnant mice were injected with DEX on E10.0-E12.0, whereas mice in the control group were injected with normal saline. Hematoxylin and eosin (HE) staining, immunohistochemistry, and real-time quantitative polymerase chain reaction were employed to evaluate the effect of DEX on fetal mouse palatal processes, particularly the changes in E-cadherin and β-catenin expression levels in the phases of the experimental and control groups.

RESULTSData indicated that the incidence of cleft palate in the DEX group was 43.59% (17/39), whereas that in the control group was only 3.03% (1/33). The results of HE staining showed that the obviously shortened palatal processes could not contact and fuse with one another in the DEX-treated mice model compared with those in the control group. The ectopic expression of E-cadherin in embryonic palatal mesenchymal cells was also analyzed. The expression levels of E-cadherin and β-catenin in the experimental group were higher than those in the control group.

CONCLUSIONThese findings indicated that DEX could induce E-cadherin gene upregulation and ectopic expression, as well as high β-catenin expression, thereby inhibiting the growth of mesenchyme cells and cleft palate.

Animals ; Cadherins ; genetics ; metabolism ; Cleft Palate ; chemically induced ; embryology ; Dexamethasone ; adverse effects ; Disease Models, Animal ; Epithelial Cells ; Female ; Glucocorticoids ; Immunohistochemistry ; Mice ; Pregnancy ; beta Catenin ; metabolism