血清HCG, AFP联合超声检查对前置胎盘植入类型的相关性分析

目的:探讨超声对植入胎盘诊断的敏感性及特异性及血清AFP、HCG和不同胎盘植入类型的相关性。方法:选取孕晚期前置胎盘产妇208例,按孕周1:1匹配,选取入无前置胎盘无胎盘植入的产妇208例为对照组。产前对所有研究对象进行胎盘超声学检查,根据术后病理将胎盘植入类型分为粘连性胎盘、植入性胎盘和穿透性胎盘组。同时测定产前、产后3 d、产后4 w血清AFP和HCG水平。结果:208例前置胎盘最终病理确诊胎盘植入67例,占32.21%(其中粘连性胎盘组31例、植入性胎盘组19例、穿透性胎盘组17例),产前超声诊断62例。超声对胎盘植入诊断总的敏感性86.56%,特异性97.16%。对照组、前置胎盘并胎盘植入组、单纯胎盘前置组胎盘厚度平均(2.34±0.63)cm、(3.27±0.78)cm、(2.42±0.61)cm,差异有统计学意义(P0.05)。粘连性胎盘植入组、植入性胎盘组、穿透性胎盘组产前、产后3 d、产后4 w各时间点血清AFP、β-HCG均明显高于对照组和前置胎盘组,差异有统计学意义(P0.05)。穿透性胎盘组产前、产后3 d、产后4 w各时间点血清AFP、β-HCG高于粘连性胎盘组和植入性胎盘组,差异有统计学意义(P0.05)。结论:超声对穿透性胎盘植入诊断具有较高的特异性和敏感性,但对粘连性胎盘植入诊断的敏感性和特异性不高,血清AFP和HCG水平和胎盘植入类型有一定关系,联合检测有助于胎盘植入类型的诊断。     

SNAT4 isoform of system A amino acid transporter is expressed in human placenta

The system A amino acid transporter is encoded by three members of the Slc38 gene family, giving rise to three subtypes: Na+-coupled neutral amino acid transporter (SNAT)1, SNAT2, and SNAT4. SNAT2 is expressed ubiquitously in mammalian tissues; SNAT1 is predominantly expressed in heart, brain, and placenta; and SNAT4 is reported to be expressed solely by the liver. In the placenta, system A has an essential role in the supply of neutral amino acids needed for fetal growth. In the present study, we examined expression and localization of SNAT1, SNAT2, and SNAT4 in human placenta during gestation. Real-time quantitative PCR was used to examine steady-state levels of system A subtype mRNA in early (6-10 wk) and late (10-13 wk) first-trimester and full-term (38-40 wk) placentas. We detected mRNA for all three isoforms from early gestation onward. There were no differences in SNAT1 and SNAT2 mRNA expression with gestation. However, SNAT4 mRNA expression was significantly higher early in the first trimester compared with the full-term placenta (P < 0.01). We next investigated SNAT4 protein expression in human placenta. In contrast to the observation for gene expression, Western blot analysis revealed that SNAT4 protein expression was significantly higher at term compared with the first trimester (P < 0.05). Immunohistochemistry and Western blot analysis showed that SNAT4 is localized to the microvillous and basal plasma membranes of the syncytiotrophoblast, suggesting a role for this isoform of system A in amino acid transport across the placenta. This study therefore provides the first evidence of SNAT4 mRNA and protein expression in the human placenta, both at the first trimester and at full term.     

The calpain system in human placenta

The calpain system is involved in a number of human pathologies ranging from the muscular dystrophies to Alzheimer's disease. It is important, therefore, to be able to obtain and to characterize both mu-calpain and m-calpain from human tissue. Although human mu-calpain can be conveniently obtained from either erythrocytes or platelets, no readily available source of human m-calpain has been described. Human placenta extracts contain both mu-calpain and m-calpain in nearly equal proportions and in significant quantities (3-4 mg mu-calpain and 4-5 mg m-calpain/1000 g placenta tissue). Placenta also contains calpastatin that elutes off ion-exchange columns over a wide range of KCl concentrations completely masking the mu-calpain activity eluting off these columns and even partly overlapping m-calpain elution. Placenta mu-calpain requires 50-70 microM Ca2+ and placenta m-calpain requires 450-460 microM Ca2+ for half-maximal proteolytic activity. Western analysis of washed placenta tissue shows that placenta contains both mu- and m-calpain, although some of the mu-calpain in whole placenta extracts likely originates from the erythrocytes that are abundant in the highly vascularized placenta. Placenta calpastatin could not be purified with conventional methods. The most prominent form of calpastatin in Western analyses of placenta obtained as soon as possible after birth was approximately 48-51 kDa; partly purified preparations of placenta calpastatin also contained 48-51 and 70 kDa polypeptides. Human placenta extracts likely contain two different calpastatin isoforms, a 48-51 kDa "placenta calpastatin" and a 70 kDa erythrocyte calpastatin.     

Origin of deoxycorticosterone and deoxycorticosterone sulfate in human pregnancy: absence of steroid 21-sulfatase activity in sulfatase-deficient placenta

The activity of steroid 21-sulfatase, the enzyme that catalyzes the hydrolysis of deoxycorticosterone sulfate (DOC-SO4) is demonstrable in human placenta. Thus, it is possible that this placental enzyme, by way of the hydrolysis of either DOC-SO4 or 21-hydroxypregnenolone mono- or di-sulfate of fetal origin, may be important in the biosynthesis of DOC, which is present in the plasma of pregnant women in high concentration. To investigate this issue further, we evaluated steroid 21-sulfatase activity in microsomal preparations of a sulfatase-deficient placenta. Immediately after delivery, at term, of a living male fetus with sulfatase deficiency, a microsome-enriched fraction of placental tissue was prepared; sulfatase activity was evaluated by use of three substrates, viz. dehydroisoandrosterone sulfate (DS), estrone sulfate (E1-SO4), and DOC-SO4, in various concentrations. Similar incubations were conducted with aliquots of a microsome-enriched fraction prepared from placental tissue of a normal fetus that was delivered, at term, within minutes of the time of delivery of the infant with sulfatase deficiency. In microsomal fractions from the normal placenta, each of the steroid sulfates was hydrolyzed. In the absence of microsomes, and in the presence of microsomal fractions from the sulfatase-deficient placenta, the hydrolysis of DOC-SO4 and DS was not detected. Moreover, in microsomes prepared from the sulfatase-deficient placenta, E1-SO4 was hydrolyzed at a rate that was only 10% of that in incubations with microsomal preparations of the normal placenta. We conclude that with sulfatase deficiency, the placenta is deficient not only in sulfatase activity for steroid-3-sulfates but for steroid 21-sulfates, e.g. DOC-SO4, as well.     

Localization and variation of TRAIL and its receptors in human placenta during gestation

The localization of TRAIL and its receptors in human placenta was studied under light microscopy using immunohistochemistry method. The variation of TRAIL and its receptors with development was also detected by in situ semi-quantification. The syncytiotrophoblast, cytotrophoblast, stromal cells and the capillary endothelium cells in human placenta all appeared to be TRAIL immunoreactive and the immunoreactive material was distributed on membrane and in cytoplasm with negative nuclei. During whole gestation there was no obvious variation of the staining of TRAIL. Although DR4, DR5, DcR1 and DcR2 can also be detected in the placenta throughout pregnancy, DR4 and DR5 staining increased with development whereas DcR1 and DcR2 staining decreased. Interestingly, at the beginning of the gestation DR4 and DR5 staining distributed on the cytotrophoblast mainly, whereas DcR1 and DcR2 mainly located in the syncytiotrophoblast cells. Collectively, these results suggest that human placenta may not only produce TRAIL but also be a TRAIL target organ, and that TRAIL/TRAILR system could take part in the self-homeostasis of placenta during whole gestation.     

Excretion of fetal biliverdin by the rat placenta-maternal liver tandem

Fetal liver immaturity is accompanied by active heme catabolism. Thus fetal biliary pigments must be excreted toward the mother by the placenta. To investigate biliverdin handling by the placenta-maternal liver tandem, biliverdin-IXalpha was administered to 21-day pregnant rats through the jugular vein or the umbilical artery of an in situ perfused placenta. Jugular administration resulted in the secretion into maternal bile of both bilirubin and biliverdin (3:1). However, when biliverdin was administered to the placenta, most of it was transformed into bilirubin before being transferred to the maternal blood. Injecting Xenopus laevis oocytes with mRNA from rat liver or placenta enhanced their ability to take up biliverdin, which was inhibited by estradiol 17beta-d-glucuronide. The expression of three OATP isoforms in this system revealed that they have a varying degrees of ability to transport biliverdin (Oatp1/1a1 > Oatp2/1a4 > Oatp4/1b2). The abundance of their mRNA in rat trophoblast was Oatp1/1a1 > Oatp4/1b2 > Oatp2/1a4. The expression of biliverdin-IXalpha reductase in rat placenta was detected by RT-PCR/sequencing and Western blot analysis. The relative abundance of biliverdin-IXalpha reductase mRNA (determined by real-time quantitative RT-PCR) was fetal liver > placenta > maternal liver. Common bile duct ligation in the last week of pregnancy induced an upregulation of biliverdin-IXalpha reductase in maternal liver but had no effect on fetal liver and placenta. In conclusion, several members of the OATP family may contribute to the uptake of fetal biliverdin by the rat placenta. Before being transferred to the mother, biliverdin is extensively converted into bilirubin by biliverdin-IXalpha reductase, whose expression is maintained even though bilirubin excretion into maternal bile is impaired.     

Ultrastructural development of chorioallantoic placenta in the Indian Miniopterus bat, Miniopterus schreibersii fuliginosus (Hodgson).

The chorioallantoic placental interhemal membrane of Miniopterus schreibersii fuliginosus has been described electron-microscopically. Morphologically there are three main types of placentae which develop in chronological sequence. They are (1) primary placenta, (2) secondary placenta and (3) tertiary placenta. In neural groove and limb-bud embryos the primary placenta consists of the following elements which separate the maternal and fetal circulations: (1) a continuous ectoplasmic layer, (2) intrasyncytial lamina, (3) syncytiotrophoblast, (4) cytotrophoblast, (5) basal lamina, (6) mesenchyme and (7) fetal endothelium. The primary placenta degenerates until term when it consists of a thin syncytiotrophoblastic layer resting on basal lamina. Mesenchyme does not show the presence of fetal capillaries. The secondary placenta is formed in early limb-bud embryos. The electron microscope has revealed that the placenta is of the endotheliomonochorial type and (1) consists of a well-developed maternal endothelium, (2) the trophoblast surrounding the maternal blood tubule is cellular, not syncytial as previously thought and the apical plasma membrane of these trophoblastic cells is in direct contact with the discontinuous interstitial membrane, (3) basal lamina, (4) mesenchyme and (5) fetal endothelium. Tertiary placenta at full term stage is of the hemodichorial type having the following elements: (1) thin ectoplasmic layer, (2) a thick intrasyncytial lamina, (3) syncytiotrophoblast, (4) cytotrophoblast, (5) basal lamina, (6) mesenchyme and (7) fetal endothelium. The definitive chorioallantoic placental barrier in this bat thus differs from the organization earlier proposed by Chari and Gopalakrishna [Proc. Indian Acad. Sci. 93: 463-483, 1984] on the basis of light-microscopic observations: (1) the absence of maternal endothelium in the primary placenta from the neural groove and early limb-bud embryos, (2) the existence of only cellular trophoblast in the secondary placenta throughout the gestation and (3) the presence of well-developed hemodichorial tertiary placenta is the unique feature of the interhemal membrane in higher Chiroptera.     

Retained placenta in Friesian mares: incidence, and potential risk factors with special emphasis on gestational length

During the foaling seasons of 1999 and 2000, the incidence of retained placenta in 495 normal parturitions of 436 Friesian brood mares was studied. Retained placenta was defined as a failure to expel all fetal membranes within 3 h of the delivery of the foal. Furthermore, the sex of the foal, month of breeding, sire and dam's sire, age of the mare, and time of day of foaling, were studied as factors that might be associated with retained placenta in Friesian mares after normal foalings, and with gestational length. The analysis was carried out using marginal logistic regression, and mixed linear regression, respectively. The incidence of retained placenta was 54%. Mean length of gestation was 331.6 days. Colts were carried 1.5 days longer than fillies. Mares bred in July-September had a 4-day shorter gestation period (329 days) than mares bred earlier in the year. There was a mare, sire, and dam's sire effect on gestational length, and a mare effect on the occurrence of retained placenta. Mares foaling at 4 and >17 years of age, tended to have a lower incidence of retained placenta than mares foaling at 5-17 years of age. No association was found between the occurrence of retained placenta, and gestational length, sex of the foal, month of breeding, dam's sire, and time of day of foaling. It was concluded that the observed high incidence of retained placenta indicates that the Friesian breed of horses has a higher risk for retained placenta than other breeds of horses.     

AQP1在CD-1纯系野生型孕鼠胎盘组织的表达

目的：研究水通道蛋白1（Aquaporin 1,AQP1）在小鼠胎盘组织的分布及表达,初步探讨AQP1在羊水循环及母胎液体平衡中的作用。方法：各取四只雌雄成年健康野生型CD1小鼠（wild type,AQP1＋/＋）及AQP1基因敲除小鼠（AQP1-KO,AQP1-/）-,将纯合子AQP1基因敲除雌雄小鼠等数量合笼交配,第二日检出阴道栓者记为妊娠第1天（1 gestational day,1GD）;野生型小鼠同样合笼记录。分别取两组13GD孕鼠的胎盘组织各一个,应用逆转录-聚合酶链反应（RT-PCR）技术及免疫组织化学技术检测AQP1胎盘组织中的表达,并确定AQP1在小鼠胎盘组织的定位。结果：1.RT-PCR结果表明AQP1在CD-1野生型孕鼠胎盘组织表达,AQP1基因敲除鼠无表达;2.免疫组织化学方法发现AQP1表达于小鼠胎盘血管内皮细胞和滋养细胞,AQP1基因敲除鼠无表达。结论：在mRNA水平和蛋白水平均发现AQP1在CD-1纯系野生型孕鼠胎盘组织的表达,提示AQP1可能在羊水循环及母胎液体平衡中发挥作用。     

AQP1 在CD-1 纯系野生型孕鼠胎盘组织的表达

目的:研究水通道蛋白1(Aquaporin 1,AQP1)在小鼠胎盘组织的分布及表达,初步探讨AQP1在羊水循环及母胎液体平衡中的作用.方法:各取四只雌雄成年健康野生型CD1小鼠(wildt ype,AQP1+/+)及AQP1基因敲除小鼠(AQP1-KO,AQP1-/-),将纯合子AQP1基因敲除雌雄小鼠等数量合笼交配,第二日检出阴道拴者记为妊娠第1天(1 gestational day,1GD);野生型小鼠同样合笼记录.分别取两组13GD孕鼠的胎盘组织各一个,应用逆转录-聚合酶链反应(RT-PCR)技术及免疫组织化学技术检测AQP1胎盘组织中的表达,并确定AQP1在小鼠胎盘组织的定位.结果:1.RT-PCR结果表明AQP1在CD-1野生型孕鼠胎盘组织表达,AQP1基因敲除鼠无表达;2.免疫组织化学方法发现AQP1表达于小鼠胎盘血管内皮细胞和滋养细胞,AQP1基因敲除鼠无表达.结论:在mRNA水平和蛋白水平均发现AQP1在CD-1纯系野生型孕鼠胎盘组织的表达,提示AQP1可能在羊水循环及母胎液体平衡中发挥作用.     

Equine retained placenta: technique for and tolerance to umbilical artery injections of collagenase

Under laboratory conditions and in clinical experiments, bacterial collagenase has proven to be effective in hydrolyzing placenta and detaching cotyledon from caruncle in the bovine species. Laboratory studies in which placental samples were incubated with collagenase have also demonstrated that collagenase is 3.7 times more effective in hydrolyzing equine placenta than bovine placenta. This led to the hypothesis that collagenase may be a potential treatment for mares with retained placenta. However, that collagenase may hydrolyze the uterine wall and perforate the uterus was a concern. It was the purpose of this study thus to determine any adverse effects of collagenase on the equine uterus and to develop a method for intraplacental injection of collagenase. Three normally expelled intact placentas from Arabian mares, 10 cyclic mixed-breed mares, and 4 mares of various breeds with retained placenta were used. Fluoroscein dye and latex were used to study the placental vasculature and to determine a suitable dose of collagenase; placentas were hydrolyzed by collagenase solution in vitro. Bacterial collagenase solution (40,000 units, 200 ml) was infused into the uterine lumen of each cyclic mare. Uterine biopsies were obtained from the mares before collagenase infusion and again at 16 h and 26 d after infusion. In the mares with retained placenta, each placenta was infused via its umbilical cord vessels with 200,000 units of bacterial collagenase in 1 L of saline. Results showed that none of the uteri from cyclic mares were damaged by collagenase treatment. During a 4-wk period of monitoring (including endoscopy) mares with retained placenta did not show any abnormalities. Retained placentas were expelled in less than 6 h after collagenase treatment. It was concluded that intraplacental injections of collagenase are a safe and potentially effective treatment for retained placenta in mares.     

Purification and properties of glutathione peroxidase from human placenta.

Glutathione peroxidase (glutathione--H2O2 oxidoreductase; EC 1.11.1.9) was purified to homogeneity from human placenta by using (NH4)2SO4 precipitation, ion-exchange chromatography, Sephadex gel filtration and preparative polyacrylamide-disc-gel electrophoresis. Glutathione peroxidase from human placenta is a tetramer, having 4g-atoms of selenium/mol of protein. The molecular weight of the enzyme is about 85000 with a subunit size of about 22,000. Kinetic properties of the enzyme are described. On incubation with cyanide, glutathione peroxidase is completely and irreversibly inactivated and selenium is released as a low-molecular-weight fragment. Reduced glutathione, beta-mercaptoethanol and dithiothreitol protect the enzyme from inactivation by cyanide and the release of selenium. Properties of human placental glutathione peroxidase are similar to those of isoenzyme A reported earlier by us from human erythrocytes. The presence of isoenzyme, B, reported earlier by us in human erythrocytes, was not detected in placenta. Also selenium-independent glutathione peroxidase (isoenzyme II), which is specific for cumene hydroperoxide, was not present in human placenta.     

Accumulation of Capsaicin in Seed, Pericarp and Placenta of Capsicum annuum L Fruit

The accumulation of capsaicin in different parts of fruit viz, placenta, pericarp and seeds of Capsicum annuum L cv Punjab Lal was compared with the activities of first four enzymes of capsaicin biosynthetic pathway at various physiological stages. Capsaicin accumulation (mg g^?1 DW) was about ten fold higher in placenta (63.96), than in pericarp (7.12) and seeds (5.06) in ripe fruits. Capsaicin accumulation was 5.79 mg g^?1 DW at 28 DAF in whole fruit. The specific activity of PAL was also ten times higher in placenta, whereas the specific activities of Ca4H, Ca3H and CaOMT were about two times higher in placenta than in other parts of fruit. The trend CaOMT > PAL > Ca4H > Ca3H was observed with peak activity at 28 DAF for Ca3H and CaOMT and at 35 DAF for PAL and Ca4H in placenta. These four enzymes showed low activity during the period up to 21 DAF, and peak activities for these enzymes were obtatined at the time of maximum growth of fruit in length and thereafter.     

人ING4的基因克隆及真核表达

目的克隆人生长抑制因子家族（inhibitor of growth famility member4,ING4）基因,构建其真核表达载体pEGFP—ING4。方法提取人胎盘总RNA,经RT—PCR扩增出ING4 cDNA,克隆至pEGFP—C2载体,构建的真核表达载体pEGFP—ING4用双酶切、基因测序进行序列鉴定;转染MCF-7细胞用荧光显微镜和免疫组化检测重组质粒的表达。结果RT—PCR产物为750bp的条带,双酶切和基因测序正确,转染可见目的蛋白融合表达。结论从人胎盘组织中成功克隆了ING4基因并构建其真核表达质粒在人MCF-7细胞中表达,为进一步研究1NG4基因的作用及抗肿瘤机制奠定了基础。     

Listeria monocytogenes traffics from maternal organs to the placenta and back

Infection with Listeria monocytogenes is a significant health problem during pregnancy. This study evaluates the role of trafficking between maternal organs and placenta in a pregnant guinea pig model of listeriosis. After intravenous inoculation of guinea pigs, the initial ratio of bacteria in maternal organs to placenta was 10(3)-10(4):1. Rapid increase of bacteria in the placenta changed the ratio to 1:1 after 24 h. Utilizing two wild-type strains, differentially marked by their susceptibility to erythromycin, we found that only a single bacterium was necessary to cause placental infection, and that L. monocytogenes trafficked from maternal organs to the placenta in small numbers. Surprisingly, bacteria trafficked in large numbers from the placenta to maternal organs. Bacterial growth, clearance, and transport between organs were simulated with a mathematical model showing that the rate of bacterial clearance relative to the rate of bacterial replication in the placenta was sufficient to explain the difference in the course of listeriosis in pregnant versus nonpregnant animals. These results provide the basis for a new model where the placenta is relatively protected from infection. Once colonized, the placenta becomes a nidus of infection resulting in massive reseeding of maternal organs, where L. monocytogenes cannot be cleared until trafficking is interrupted by expulsion of the infected placental tissues.     

The purification and identification of calmodulin from human placenta

A protein which showed similarity to bovine brain calmodulin in electrophoretic mobilities on polyacrylamide gels in the presence of 40% glycerol (pH 8.6) and 0.1% sodium dodecyl sulfate (pH 7.2) was isolated from human placenta. Its final yield was approx. 4 mg per kg human placenta. The placenta protein was similar to bovine brain calmodulin in stimulating bovine brain calmodulin-deficient cyclic nucleotide phosphodiesterase in the presence of calcium. However, its stimulating activity was eliminated by ethyleneglycol-bis(beta-aminoethyl ether)-N,N'-tetraacetic acid (EGTA) or trifluoperazine. In addition, there is a close resemblance in amino acid composition between the placental protein and bovine brain calmodulin. These results indicate that calmodulin is present in human placenta.     

Human placenta S-adenosylmethionine: protein carboxyl O-methyltransferase (protein methylase II). Purification and characterization

1. Protein methylase II was purified from human placenta approx. 8700-fold with a yield of 14%. 2. Unlike protein methylase II from other sources, the activity of human placenta enzyme was completely inhibited by 2 mM Cu2+. Other divalent ions were without effect. 3. Human chorionic gonadotropin (HCG), immunoglobulin A and calf thymus histones served as good in vitro substrates for the enzyme, particularly HCG. 4. The Km for S-adenosyl-L-methionine and Ki for S-adenosyl-L-homocysteine were 2.08 x 10(-6) and 5.8 x 10(-7) M, respectively. 5. The protein methylase II activity in human placenta changed with gestational age, the activity at 1st and 2nd trimester being approximately twice that of term placenta.     

The expression of proprotein convertase PACE4 is highly regulated by Hash-2 in placenta: possible role of placenta-specific basic helix-loop-helix transcription factor, human achaete-scute homologue-2

PACE4 is a member of the mammalian subtilisin-like proprotein convertase (SPC) family, which contribute to the activation of transforming growth factor (TGF) beta family proteins. We previously reported that PACE4 is highly expressed in syncytiotrophoblasts of human placenta [Tsuji et al. (2003) BIOCHIM: Biophys. Acta 1645, 95-104]. In this study, the regulatory mechanism for PACE4 expression in placenta was analyzed using a human placental choriocarcinoma cell line, BeWo cells. Promoter analysis indicated that an E-box cluster (E4-E9) in the 5'-flanking region of the PACE4 gene acts as a negative regulatory element. The binding of human achaete-scute homologue 2 (Hash-2) to the E-box cluster was shown by gel mobility-shift assay. The overexpression of Hash-2 caused a marked decrease in PACE4 gene expression. When BeWo cells were grown under low oxygen (2%) conditions, the expression of Hash-2 decreased, while that of PACE4 increased. In both cases, other SPCs, such as furin, PC5/6, and PC7/8, were not affected. Further, PACE4 expression was found to be developmentally regulated in rat placenta. By in situ hybridization, Mash-2 (mammalian achaete-scute homologue 2) mRNA was found to be expressed in the spongiotrophoblast layer where PACE4 was not expressed. In contrast, the PACE4 mRNA was expressed mainly in the labyrinthine layer where Mash-2 was not detected. These results suggest that PACE4 expression is down-regulated by Hash-2/Mash-2 in both human and rat placenta and that many bioactive proteins might be regulated by PACE4 activity.     

Paternal obesity induces epigenetic aberrations and gene expression changes in placenta and fetus

Paternal epigenome regulates placental and fetal growth. However, the effect of paternal obesity on placenta and its subsequent effect on the fetus via sperm remains unknown. We previously discovered abnormal methylation of imprinted genes involved in placental and fetal development in the spermatozoa of obese rats. In the present study, elaborate epigenetic characterization of sperm, placenta, and fetus was performed. For 16 weeks, male rats were fed either control or a high-fat diet. Following mating studies, sperm, placenta, and fetal tissue were collected. Significant changes were observed in placental weights, morphology, and cell populations. Methylation status of imprinted genes—Igf2, Peg3, Cdkn1c, and Gnas in spermatozoa, correlated with their expression in the placenta and fetus. Placental DNA methylating enzymes and 5-methylCytosine levels increased. Furthermore, in spermatozoa, DNA methylation of a few genes involved in pathways associated with placental endocrine function—gonadotropin-releasing hormone, prolactin, estrogen, and vascular endothelial growth factor, correlated with their expression in placenta and fetus. Changes in histone-modifying enzymes were also observed in the placenta. Histone marks H3K4me3, H3K9me3, and H4ac were downregulated, while H3K27me3 and H3ac were upregulated in placentas derived from obese male rats. This study shows that obesity-related changes in sperm methylome translate into abnormal expression in the F1-placenta fathered by the obese male, presumably affecting placental and fetal development.     

Benzylamine oxidase activity in rat embryo and placenta at organogenesis

Benzylamine oxidase, characterized by its sensitivity to semi-carbazide (1 X 10(-2) mol/l) inhibition and its insensitivity to deprenyl (4 X 10(-4) mol/l) inhibition, is present in rat placenta during days 10-15 of the gestation period and in the embryo at days 11-15. The activity represents a substantial part of the overall activity observed with p-chlorobenzylamine as substrate. A much higher activity is present in the placenta than in the embryo.