The vomeronasal organ has an important role in mammal's social and sexual behaviours. In addition, it mediates defensive behavior through detection of protein pheromone homologues. In this work, a detailed morphological description of the postnatal development of the non-sensory epithelium (NSE) lining the vomeronasal duct (VND) of the female cat is provided using various histological techniques. The study focused on newborn, 2 weeks, 4 weeks, and 8 weeks of postnatal ages using four animals for each age. We report here for the first time that three types of NSE line the rostral segment of the VND; nonkeratinized stratified squamous epithelium, stratified cuboidal epithelium, and ciliated pseudo stratified columnar ciliated epithelium with goblet cells and that the VND undergoes 90° a change in its its axis from the vertical position caudally to the horizontal position rostral. The NSE which lines the lateral side of the VND middle segment is consists of cliated pseudostratified columnar epithelium without goblet cells. In addition to basal cells, the NSE contains ciliated and three types of nonciliated columnar epithelial cells (dark, light, and unstained). Mitotic figures were observed only in the basal cells layer during the first 2 weeks of postnatal development. Intraepithelial invading inflammatory cells were uncommon. Scanning electron microscopy revealed unevenly distributed long cilia intermingled with microvillar processes and intervening short microvillar processes. These projecting cilia and microvilli revealed a gradual increase in their height during development toward maturity.
Animals ; Cats* ; Cilia ; Epithelial Cells ; Epithelium* ; Female ; Goblet Cells ; Histological Techniques ; Humans ; Infant, Newborn ; Microscopy, Electron, Scanning ; Microvilli ; Vomeronasal Organ*

PURPOSE: Pulmonary surfactants for preterm infants contain mostly animal-derived surfactant proteins (SPs), which are essential for lowering surface tension. We prepared artificial pulmonary surfactants using synthetic human SP analogs and performed in vitro and in vivo experiments. MATERIALS AND METHODS: We synthesized peptide analogues that resemble human SP-B (RMLPQLVCRLVLRCSMD) and SP-C (CPVHLKRLLLLLLLLLLLLLLLL). Dipalmitoylphosphatidylcholine (DPPC), phosphatidylglycerol (PG), and palmitic acid (PA) were added and mixed in lyophilized to render powdered surfactant. Synsurf-1 was composed of DPPC:PG:PA:SP-B (75:25:10:3, w/w); Synsurf-2 was composed of DPPC:PG:PA:SP-C (75:25:10:3, w/w); and Synsurf-3 was composed of DPPC:PG:PA:SP-B:SP-C (75:25:10:3:3, w/w). We performed in vitro study to compare the physical characteristics using pulsating bubble surfactometer and modified Wilhelmy balance test. Surface spreading and adsorption test of the surfactant preparations were measured. In vivo test was performed using term and preterm rabbit pups. Pressure-volume curves were generated during the deflation phase. Histologic findings were examined. RESULTS: Pulsating bubble surfactometer readings revealed following minimum and maximum surface tension (mN/m) at 5 minutes: Surfacten® (5.5±0.4, 32.8±1.6), Synsurf-1 (16.7±0.6, 28.7±1.5), Synsurf-2 (7.9±1.0, 33.1±1.6), and Synsurf-3 (7.1±0.8, 34.5±1.0). Surface spreading rates were as follows: Surfacten® (27 mN/m), Synsurf-1 (43 mN/m), Synsurf-2 (27 mN/m), and Synsurf-3 (27 mN/m). Surface adsorption rate results were as follows: Surfacten® (28 mN/m), Synsurf-1 (35 mN/m), Synsurf-2 (29 mN/m), and Synsurf-3 (27 mN/m). The deflation curves were best for Synsurf-3; those for Synsurf-2 were better than those for Surfacten®. Synsurf-1 was the worst surfactant preparation. Microscopic examination showed the largest aerated area of the alveoli in the Synsurf-3 group, followed by Synsurf-1 and Surfacten®; Synsurf-2 was the smallest. CONCLUSION: Synsurf-3 containing both SP-B and SP-C synthetic analogs showed comparable and better efficacy than commercially used Surfacten® in lowering surface tension, pressure-volume curves, and tissue aerated area of the alveoli.
1,2-Dipalmitoylphosphatidylcholine ; Adsorption ; Animal Experimentation* ; Animals* ; Humans ; In Vitro Techniques* ; Infant, Newborn ; Infant, Premature ; Palmitic Acid ; Pulmonary Surfactant-Associated Proteins ; Pulmonary Surfactants ; Reading ; Surface Tension

OBJECTIVETo investigate the long-term effect of oligodendrocyte precursor cell (OPC) transplantation on a rat model of white matter injury (WMI) in the preterm infant.

METHODSA total of 80 Sprague-Dawley rats aged 3 days were randomly divided into sham-operation group, model control group, 5-day ventricular/white matter transplantation group, 9-day ventricular/white matter transplantation group, 14-day ventricular/white matter transplantation group (n=10 each). All groups except the sham-operation group were treated with right common carotid artery ligation and hypoxia for 80 minutes to establish a rat model of WMI in the preterm infant. OPCs were prepared from the human fetal brain tissue (10-12 gestational weeks). At 5, 9, and 14 days after modeling, 3×10OPCs were injected into the right lateral ventricle or white matter in each transplantation group, and myelin sheath and neurological function were evaluated under an electron microscope at ages of 60 and 90 days.

RESULTSElectron microscopy showed that at an age of 60 days, each transplantation group had a slight improvement in myelin sheath injury compared with the model control group; at an age of 90 days, each transplantation group had significantly thickened myelin sheath and reduced structural damage compared with the model control group, and the 14-day transplantation groups had the most significant changes. There were no significant differences in the degree of myelin sheath injury between the ventricular and white matter transplantation groups at different time points. At an age of 60 or 90 days, the transplantation groups had a significantly higher modified neurological severity score (mNSS) than the sham-operation group and a significantly lower mNSS than the model control group (P<0.05).

CONCLUSIONSOPC transplantation may have a long-term effect in the treatment of WMI in the preterm infant, and delayed transplantation may enhance its therapeutic effect.

Animals ; Animals, Newborn ; Disease Models, Animal ; Myelin Sheath ; pathology ; Oligodendrocyte Precursor Cells ; transplantation ; Rats ; Rats, Sprague-Dawley ; White Matter ; injuries ; pathology ; ultrastructure

OBJECTIVETo investigate the expression of autophagic gene and circadian gene in the neurons of neonatal rats after hypoxic-ischemic brain damage and the mechanism of nerve injury induced by hypoxia/ischemia.

METHODSTwelve Sprague-Dawley (SD) rats were randomly divided into hypoxic-ischemic (HI) group and sham-operation group, with 6 rats in each group. Ligation of the right common carotid artery and hypoxic treatment were performed to establish a model of hypoxic-ischemic brain damage. Western blot was used to measure the expression of the circadian protein Clock in the cortex and hippocampus. The neurons of the rats were cultured in vitro and randomly divided into oxygen glucose deprivation (OGD) group and control group. The neurons in the OGD group were treated with DMEM medium without glucose or serum to simulate ischemic state, and hypoxic treatment was performed to establish an in vitro model of hypoxic-ischemic brain damage. Western blot was used to measure the expression of autophagy-related proteins Beclin1 and LC3 and Clock protein at different time points. The changes in the expression of Beclin1 and LC3 were measured after the expression of Clock protein in neurons was inhibited by small interfering RNA technique.

RESULTSThe expression of autophagy-related proteins Beclin1 and LC3Ⅱ in neurons cultured in vitro displayed a rhythmic fluctuation; after OGD treatment, the expression of Beclin1 and LC3Ⅱ gradually increased over the time of treatment and no longer had a rhythmic fluctuation. Compared with the sham-operation group, the HI group had a significant reduction in the expression of Clock protein in the cortex and hippocampus (P<0.05). After OGD treatment, the neurons cultured in vitro had a significant reduction in the expression of Clock protein (P<0.05). Compared with the negative control group, the Clock gene inhibition group had significant reductions in the expression of Beclin1 and LC3Ⅱ (P<0.05).

CONCLUSIONSHypoxia/ischemia induces the disorder in the expression rhythm of autophagy-related proteins Beclin1 and LC3, and the mechanism may be associated with the fact that the circadian protein Clock participates in the regulation of the expression of Beclin1 and LC3.

Animals ; Animals, Newborn ; Autophagy ; genetics ; Beclin-1 ; genetics ; Circadian Rhythm ; Female ; Hypoxia-Ischemia, Brain ; metabolism ; Male ; Microtubule-Associated Proteins ; genetics ; Neurons ; metabolism ; Rats ; Rats, Sprague-Dawley

BACKGROUND AND PURPOSE: Lacosamide (LCM) is an antiepileptic drug that enhances the slow inactivation of sodium channels and modulates collapsin response mediator protein-2. LCM was recently demonstrated to exert a neuroprotective effect in a murine model of traumatic brain injury and status epilepticus. Assuming the same underlying excitotoxicity-related brain injury mechanism, we hypothesized that LCM would have a neuroprotective effect in hypoxic-ischemic brain injury. METHODS: We divided rats into three groups at each testing session: pre- or postfed with LCM, fed with normal saline, and sham. A hypoxic-ischemic brain injury was induced by subjecting 7-day-old rats to right carotid artery coagulation followed by 2.5 h of exposure to 8% oxygen. The animals were killed on postnatal day 12 to evaluate the severity of brain damage. Open field testing was also performed between week 2 and week 6, and the Morris water maze test was performed in week 7 after hypoxia-ischemia. RESULTS: The incidence of liquefactive cerebral infarction was lower in rats prefed with LCM at 100 mg/kg/dose, with the mortality rate being higher at higher doses (200 and 300 mg/kg/dose). The infarct areas were smaller in LCM-prefed rats in several brain regions including the hemisphere, hippocampus, cortex, and striatum. Spatial learning and memory function were better in LCM-prefed rats (p<0.05). No effect was observed in postfed rats. CONCLUSIONS: This study suggests that LCM pretreatment exerts a neuroprotective effect on hypoxia-ischemia in neonatal rats. The obtained results suggest that LCM pretreatment could be used as an effective neuroprotective method for neonates under hypoxic-ischemic conditions including heart surgery.
Animals ; Brain Injuries* ; Brain* ; Carotid Arteries ; Cerebral Infarction ; Hippocampus ; Humans ; Incidence ; Infant, Newborn ; Memory ; Methods ; Mortality ; Neuroprotection ; Neuroprotective Agents* ; Oxygen ; Rats* ; Semaphorin-3A ; Sodium Channels ; Spatial Learning ; Status Epilepticus ; Thoracic Surgery ; Water

No abstract available.
Animals ; Busulfan* ; Fetal Blood* ; Humans* ; Infant, Newborn* ; Liver* ; Mice* ; Umbilical Cord*

BACKGROUNDRecombinant human-erythropoietin (rh-EPO) has therapeutic efficacy for premature infants with brain damage during the active rehabilitation and anti-inflammation. In the present study, we found that the rh-EPO was related to the promotion of neovascularization. Our aim was to investigate whether rh-EPO augments neovascularization in the neonatal rat model of premature brain damage through the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) signaling pathway.

METHODSPostnatal day 5 (PD5), rats underwent permanent ligation of the right common carotid artery and were exposed to hypoxia for 2 h. All the rat pups were randomized into five groups as follows: (1) control group; (2) hypoxia-ischemic (HI) group; (3) HI + LY294002 group; (4) HI + rh-EPO group; and (5) HI + rh-EPO + LY294002 group. The phospho-Akt protein was tested 90 min after the whole operation, and CD34, vascular endothelial growth factor receptor 2 (VEGFR2), and vascular endothelial growth factor (VEGF) were also tested 2 days after the whole operation.

RESULTSIn the hypoxic and ischemic zone of the premature rat brain, the rh-EPO induced CD34+ cells to immigrate to the HI brain zone (P < 0.05) and also upregulated the VEGFR2 protein expression (P < 0.05) and VEGF mRNA level (P < 0.05) through the PI3K/Akt (P < 0.05) signaling pathway when compared with other groups.

CONCLUSIONSThe rh-EPO treatment augments neovascularization responses in the neonatal rat model of premature brain damage through the PI3K/Akt signaling pathway. Besides, the endogenous EPO may exist in the HI zone of rat brain and also has neovascularization function through the PI3K/Akt signaling pathway.

Animals ; Animals, Newborn ; Antigens, CD34 ; metabolism ; Brain ; drug effects ; metabolism ; pathology ; Disease Models, Animal ; Erythropoietin ; genetics ; metabolism ; therapeutic use ; Female ; Humans ; Hypoxia-Ischemia, Brain ; drug therapy ; metabolism ; Neovascularization, Physiologic ; drug effects ; Phosphatidylinositol 3-Kinase ; metabolism ; Pregnancy ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; genetics ; metabolism ; therapeutic use ; Signal Transduction ; drug effects ; Vascular Endothelial Growth Factor A ; genetics ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism

OBJECTIVETo explore the effects of rat bone mesenchymal stem cell (BMSC) transplantation on retinal neovascularization, and to observe the changes of hypoxia-inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factors (VEGF) in rats with oxygen-induced retinopathy (OIR).

METHODSSeventy-two seven-day-old Sprague-Dawley rats were randomly divided into three groups: normal control (CON), model (OIR) and BMSC transplantation. In the BMSC transplantation group, BMSCs were transplanted 5 days after oxygen conditioning. The phosphate buffered saline of the same volume was injected in the CON and OIR groups. The OIR model was prerpared according to the classic hyperoxygen method. At seven days after transplantation, retinal neovascularization was examined by retinal flat-mount staining and hematoxylin eosin (HE) staining. The expression of HIF-1α and VEGF proteins was examined by immunohistochemistry staining and Western blot analysis.

RESULTSThe retinal flat-mount staining results showed that the vessels were well organized in the CON group, but the vessels were irregularly organized, and lots of nonperfusion areas were observed in the OIR group. The large vessels were a bit circuitous, the retinal vessels were relatively organized, and less nonperfusion areas were noted in the BMSC transplantation group. The HE staining results showed that many neovessels and preretinal neovascular (pre-RNC) cells were observed on the internal limiting membrane in the OIR group. There were less pre-RNC cells in the BMSC transplantation group compared with the OIR group (P<0.01). The immunohistochemistry analysis showed that more HIF-1αand VEGFcells were observed in the OIR group compared with the CON group, and less HIF-1αand VEGFcells were observed in the BMSC transplantation group compared with OIR group (P<0.05). The Western blot analysis showed the expression of HIF-1α and VEGF proteins in the OIR group was significantly higher than that in the CON group. The expression of HIF-1α and VEGF proteins in the BMSC transplantation group was lower than that in the OIR group (P<0.01).

CONCLUSIONSBMSC transplantation therapy could alleviate retinal neovascularization in OIR rats, and its mechanisms might be associated with the inhibition of the expression of HIF-1α and VEGF proteins.

Animals ; Animals, Newborn ; Female ; Hypoxia-Inducible Factor 1, alpha Subunit ; analysis ; Male ; Mesenchymal Stem Cell Transplantation ; Rats ; Rats, Sprague-Dawley ; Retina ; chemistry ; Retinal Neovascularization ; prevention & control ; Retinopathy of Prematurity ; metabolism ; therapy ; Vascular Endothelial Growth Factor A ; analysis

OBJECTIVETo explore the mechanisms of neuroprotective effects of c-Jun N-terminal kinase (JNK)/FOXO3a transcription factor signaling pathway inhibition on hypoxic-ischemic neuronal apoptosis in neonatal rats with hypoxic-ischemic brain damage (HIBD).

METHODSSixty-four 7-day-old Sprague-Dawley rats were divided into four groups: hypoxia-ischemia (HI), sham-operated, JNK specific inhibitor AS601245-treated, and DMSO vehicle. Rats' cerebral cortexes were collected at 24 hours after HI. Western blot was used to detect the protein expression of JNK, p-JNK, FOXO3a, nuclear and cytoplasmic FOXO3a, Bim, and CC3. TUNEL staining was used to detect the apoptotic cells.

RESULTSCompared with the sham-operated group, p-JNK protein increased (P<0.01), nuclear protein of FOXO3a increased (P<0.01), cytoplasmic protein decreased (P<0.01), and pro-apoptotic proteins Bim and CC3 increased 24 hours after HI (P<0.01). Compared with the HI and DMSO vehicle groups, p-JNK protein was reduced (P<0.01), nuclear protein of FOXO3a was also reduced (P<0.01), cytoplasmic protein increased (P<0.01), and Bim and CC3 proteins decreased (P<0.01) in the AS601245-treated group 24 hours after HI. TUNEL positive cells were reduced in the AS601245-treated rats compared with the HI and DMSO vehicle groups 24 hours after HI (P<0.01).

CONCLUSIONSJNK activity increases in the neonatal rat brain with HI damage. JNK activity inhibition can inhibit FOXO3a translocation from cytoplasm to nucleus and downregulate the levels of pro-apoptotic proteins Bim and CC3, leading to the reduction of neuronal apoptosis.

Active Transport, Cell Nucleus ; Animals ; Animals, Newborn ; Apoptosis ; Cell Nucleus ; metabolism ; Female ; Forkhead Box Protein O3 ; metabolism ; Hypoxia-Ischemia, Brain ; pathology ; JNK Mitogen-Activated Protein Kinases ; physiology ; Male ; Neurons ; pathology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate mitophagy in an animal model of hypoxic-ischemic brain damage (HIBD) and its role in HIBD.

METHODSA total of 120 neonatal Sprague-Dawley rats aged 7 days were divided into three groups: sham-operation, HIBD, and autophagy inhibitor intervention (3MA group). The rats in the HIBD group were treated with right common carotid artery ligation and then put in a hypoxic chamber (8% oxygen and 92% nitrogen) for 2.5 hours. Those in the 3MA group were given ligation and hypoxic treatment at 30 minutes after intraperitoneal injection of 2 μL 3MA. Those in the sham-operation group were not given ligation or hypoxic treatment. Single cell suspension was obtained from all groups after model establishment. Immunofluorescence localization was performed for mitochondria labeled with MitoTracker, autophagosomes labeled with LysoTracker, and autophagy labeled with LC3 to observe mitophagy. After staining with the fluorescent probe JC-1, flow cytometry was used to measure mitochondrial membrane potential. TTC staining was used to measure infarct volume. Cytoplasmic proteins in cortical neurons were extracted, and Western blot was used to measure the expression of mitophagy-related proteins.

RESULTSCompared with the sham-operation group, the HIBD group had a significant reduction in mitochondrial membrane potential (P<0.05), a significant increase in mitophagy (P<0.05), a significant increase in the expression of the proteins associated with the division of the mitochondrial Drp1 and Fis1 (P<0.05), and a significant reduction in the expression of the mitochondrial outer membrane protein Tom20 and the mitochondrial inner membrane protein Tim23 (P<0.05). Compared with the HIBD group, the 3MA group had a significantly greater reduction in mitochondrial membrane potential (P<0.05), but showed significantly reduced mitophagy (P<0.05). In addition, the 3MA group had a significantly increased degree of cerebral infarction compared with the HIBD group (P<0.05).

CONCLUSIONSHIBD can increase the degree of mitophagy, and the inhibition of mitophagy can aggravate HIBD in neonatal rats.

Animals ; Animals, Newborn ; Female ; Hypoxia-Ischemia, Brain ; etiology ; physiopathology ; Male ; Mitochondrial Degradation ; physiology ; Rats ; Rats, Sprague-Dawley