Increased proliferation and neuronal fate in prairie vole brain progenitor cells cultured in vitro: effects by social exposure and sexual dimorphism.

BACKGROUND: The prairie vole (Microtus ochrogaster) is a socially monogamous rodent that establishes an enduring pair bond after cohabitation, with (6 h) or without (24 h) mating. Previously, we reported that social interaction and mating increased cell proliferation and differentiation to neuronal fate in neurogenic niches in male voles. We hypothesized that neurogenesis may be a neural plasticity mechanism involved in mating-induced pair bond formation. Here, we evaluated the differentiation potential of neural progenitor cells (NPCs) isolated from the subventricular zone (SVZ) of both female and male adult voles as a function of sociosexual experience. Animals were assigned to one of the following groups: (1) control (Co), sexually naive female and male voles that had no contact with another vole of the opposite sex; (2) social exposure (SE), males and females exposed to olfactory, auditory, and visual stimuli from a vole of the opposite sex, but without physical contact; and (3) social cohabitation with mating (SCM), male and female voles copulating to induce pair bonding formation. Subsequently, the NPCs were isolated from the SVZ, maintained, and supplemented with growth factors to form neurospheres in vitro. RESULTS: Notably, we detected in SE and SCM voles, a higher proliferation of neurosphere-derived Nestin + cells, as well as an increase in mature neurons (MAP2 +) and a decrease in glial (GFAP +) differentiated cells with some sex differences. These data suggest that when voles are exposed to sociosexual experiences that induce pair bonding, undifferentiated cells of the SVZ acquire a commitment to a neuronal lineage, and the determined potential of the neurosphere is conserved despite adaptations under in vitro conditions. Finally, we repeated the culture to obtain neurospheres under treatments with different hormones and factors (brain-derived neurotrophic factor, estradiol, prolactin, oxytocin, and progesterone); the ability of SVZ-isolated cells to generate neurospheres and differentiate in vitro into neurons or glial lineages in response to hormones or factors is also dependent on sex and sociosexual context. CONCLUSION: Social interactions that promote pair bonding in voles change the properties of cells isolated from the SVZ. Thus, SE or SCM induces a bias in the differentiation potential in both sexes, while SE is sufficient to promote proliferation in SVZ-isolated cells from male brains. In females, proliferation increases when mating is performed. The next question is whether the rise in proliferation and neurogenesis of cells from the SVZ are plastic processes essential for establishing, enhancing, maintaining, or accelerating pair bond formation. Highlights 1. Sociosexual experiences that promote pair bonding (social exposure and social cohabitation with mating) induce changes in the properties of neural stem/progenitor cells isolated from the SVZ in adult prairie voles. 2. Social interactions lead to increased proliferation and induce a bias in the differentiation potential of SVZ-isolated cells in both male and female voles. 3. The differentiation potential of SVZ-isolated cells is conserved under in vitro conditions, suggesting a commitment to a neuronal lineage under a sociosexual context. 4. Hormonal and growth factors treatments (brain-derived neurotrophic factor, estradiol, prolactin, oxytocin, and progesterone) affect the generation and differentiation of neurospheres, with dependencies on sex and sociosexual context. 5. Proliferation and neurogenesis in the SVZ may play a crucial role in establishing, enhancing, maintaining, or accelerating pair bond formation.

In this study, researchers evaluated whether social interactions and copulation induce changes in the proliferation and differentiation of neural progenitor cells in adult male and female voles using an in vitro neurosphere formation assay. The following groups were assigned: control animals without any exposure to another vole outside their litter, another group with social exposure consisting of sensory exposure to a vole of the opposite sex and a third group with social cohabitation and copulation. Forty eight hours after social interactions, cells were isolated from the neurogenic niche subventricular zone (SVZ) and cultured to assess their self-renewal and proliferation abilities to form neurospheres. The results showed in the social interaction groups, a greater number and growth of neurospheres in both males and females. Differentiation capacity was assessed by immunodetection of MAP2 and GFAP to identify neurons or glia, respectively, arise from neurospheres, with an increase in neuronal fate in groups with social interaction. In the second part of the study, the researchers analyzed the effect of different hormone and growth factor treatments and found that the response in both proliferation and differentiation potential may vary depending on the sociosexual context or sex. This study suggests that social interactions leading to pair bond formation alter the properties of SVZ cells, whereby proliferation and neurogenesis may have an impact on the establishment and maintenance of pair bonding.

Association of the EPAS1 rs7557402 Polymorphism with Hemodynamically Significant Patent Ductus Arteriosus Closure Failure in Premature Newborns under Pharmacological Treatment with Ibuprofen.

Patent ductus arteriosus (PDA) is frequent in preterm newborns, and its incidence is inversely associated with the degree of prematurity. The first choice of pharmacological treatment is ibuprofen. Several genes, including EPAS1, have been proposed as probable markers associated with a genetic predisposition for the development of PDA in preterm infants. EPAS 1 NG_016000.1:g.84131C>G or rs7557402 has been reported to be probably benign and associated with familial erythrocytosis by the Illumina Clinical Services Laboratory. Other variants of EPAS1 have been previously reported to be benign for familial erythrocytosis because they decrease gene function and are positive for familial erythrocytosis because the overexpression of EPAS1 is a key factor in uncontrolled erythrocyte proliferation. However, this could be inconvenient for ductal closure, since for this process to occur, cell proliferation, migration, and differentiation should take place, and a decrease in EPAS1 gene activity would negatively affect these processes. Single-nucleotide polymorphisms (SNPs) in EPAS1 and TFAP2B genes were searched with high-resolution melting and Sanger sequencing in blood samples of preterm infants with hemodynamically significant PDA treated with ibuprofen at the National Institute of Perinatology. The variant rs7557402, present in the EPAS1 gene eighth intron, was associated with a decreased response to treatment (p = 0.007, OR = 3.53). The SNP rs7557402 was associated with an increased risk of pharmacological treatment failure. A probable mechanism involved could be the decreased activity of the product of the EPAS1 gene.

Pluripotent Stem Cells as a Model for Human Embryogenesis.

Pluripotent stem cells (PSCs; embryonic stem cells and induced pluripotent stem cells) can recapitulate critical aspects of the early stages of embryonic development; therefore, they became a powerful tool for the in vitro study of molecular mechanisms that underlie blastocyst formation, implantation, the spectrum of pluripotency and the beginning of gastrulation, among other processes. Traditionally, PSCs were studied in 2D cultures or monolayers, without considering the spatial organization of a developing embryo. However, recent research demonstrated that PSCs can form 3D structures that simulate the blastocyst and gastrula stages and other events, such as amniotic cavity formation or somitogenesis. This breakthrough provides an unparalleled opportunity to study human embryogenesis by examining the interactions, cytoarchitecture and spatial organization among multiple cell lineages, which have long remained a mystery due to the limitations of studying in utero human embryos. In this review, we will provide an overview of how experimental embryology currently utilizes models such as blastoids, gastruloids and other 3D aggregates derived from PSCs to advance our understanding of the intricate processes involved in human embryo development.

Pure trisomy 2p syndrome in two siblings with an unbalanced translocation and minimal terminal 12q monosomy characterized by high-density microarray.

Pure partial trisomy 2p patients have rarely been reported. Oligonucleotide array analysis has proved to be important for examining 2p rearrangements to delineate the involved segment and to rule out additional imbalances modifying the phenotype. Here, we report 2 siblings with an unbalanced translocation that led to a partial trisomy 2p (p22.3pter) and a terminal deletion of 12q (q24.33qter). This finding was characterized by the molecular karyotyping of both siblings. The 12q loss spanned approximately 300 kb and did not yield clinical features in our patients. The trisomic region in the short arm of chromosome 2 spanned 32.8 Mb and yielded phenotypic features of pure distal 2p trisomy, notably facial anomalies, growth failure, and psychomotor delay. The clinical features of our patients help to delineate the phenotype of the pure trisomy 2p syndrome. Patient 2 also showed a horseshoe kidney which is a previously unrecognized defect associated with this syndrome.

El papel de la genética en la restricción del crecimiento intrauterino / The role of genetics in fetal growth restriction

Se define como restricción del crecimiento intrauterino (RCIU) a la alteración en el crecimiento fetal que determina un peso por debajo de la percentila 10 para la edad gestacional. Las causas genéticas de RCIU pueden dividirse en: cromosómicas, alteraciones de la epigenética o impronta y síndromes génicos. Se presenta el caso de una paciente con RCIU referida por sospecha de displasia ósea, en la que se descartó disfunción vascular placentaria por ultrasonido prenatal, infecciones, patología materna y displasias óseas por estudio radiológico normal. Se realizó cariotipo en el cordón umbilical y en tres diferentes sitios de la placenta por la posibilidad de un mosaico placentario, obteniéndose un resultado normal. Al nacimiento presentó peso y talla por debajo de la percentila 3, cráneo dolicocéfalo con frontal prominente, fontanela anterior amplia, cara pequeña, triangular con mentón en punta y clinodactilia bilateral. A los dos meses de edad se observó asimetría de extremidades inferiores y se refirió reflujo gastroesofágico. Con base en los criterios clínicos y resultados obtenidos se realizó el diagnóstico de síndrome de Silver-Russell.

Intrauterine growth restriction (IUGR) is an alteration in fetal development in which the fetal weight is below the 10th percentile for gestational age. The genetic causes of IUGR can be classified as: chromosomal, epigenetic and other imprinting disorders and monogenic syndromes. We report a patient with IUGR referred to our hospital with the prenatal diagnosis of achondroplasia. Vascular malfunction of the placentae, maternal pathology, and skeletal dysplasia were discarded. A karyotype in umbilical cord and in three different placental spots was performed, with a normal result in all of them, ruling out placentae mosaicism. At birth, the weight and height were below the 3th percentile. Physical examination showed: dolicocephaly, frontal prominence, large fontanels, small and triangular face, pointed chin and incurved bilateral fifth fingers. Two months later a lower limb asymmetry was noticed and gastroesophageal reflux was referred. With these clinical abnormalities and the studies performed the diagnosis of Silver-Russell syndrome was established.

Prenatal prevalence of skeletal dysplasias and a proposal ultrasonographic diagnosis approach.

OBJECTIVE: To determine the prevalence of fetal bone dysplasias diagnosed at the Department of Maternal Fetal Medicine (UNIMEF) of the Instituto Nacional de Perinatologia (INPer); and to describe the most frequent skeletal dysplasias and to propose a diagnostic flow chart. MATERIALS AND METHODS: This is a case series study including skeletal dysplasias cases from January 1995 until December 2009 at the UNIMEF Statistical analysis was performed using SPSS 12 statistical software. RESULTS: A total of 81,892 births were registered at the institution during the study period. The prevalence of bone dysplasia was 8.1 per 10,000 births. We used a diagnostic flow chart that was developed at our institution to diagnose skeletal dysplasias. Micromelia (n = 40, 59.7%) and both rhizomelia and mesomelia (n = 17, 25.3%) were highly prevalent. We found other structural anomalies in 40 cases (61.1%), which were associated with different skeletal dysplasias; these other anomalies were mainly congenital heart diseases (12 cases) with a predominance of ventricular septal defects. There was polyhydramnios in 43.2% of cases. The mean of the gestational age at diagnosis was 24.5 weeks (SD 5.66). The karyotype was obtained in 11.9% (8/67) of cases. A total of 7 stillbirths and 11 neonatal deaths were registered, of which only 10 cases received a necropsy. Births occurred in the third trimester for 88% of cases, of which 85% were born via Cesarean section, whereas in the second trimester, the vaginal approach was chosen in 100% of cases. CONCLUSIONS: The prenatal diagnosis of bone dysplasias is challenging due to the late development of the diagnostic features. Nevertheless, using ultrasonography in a systematic approach, in conjunction with a multidisciplinary approach, is a key factor in the diagnosis of this disease during the fetal period.

Major craniofacial defects: case series and prenatal diagnosis at the Instituto Nacional de Perinatología, Mexico.

OBJECTIVE: To describe the prenatal diagnosis, characteristics, development, perinatal outcome, and final diagnosis of pregnancies complicated by fetuses with major craniofacial defects, at the Instituto Nacional de Perinatologia, México, 1997-2008. MATERIAL AND METHODS: A retrospective, descriptive study from January of 1997 to January 2008, analyzed 152 pregnancies complicated by fetuses with major craniofacial defects, diagnosed at the Department of Fetal Medicine of the National Institute of Perinatology. Data were obtained from patients clinical records. RESULTS: . The mean age was 28 +/- 8 years, with the largest number of cases between 20 and 24. The mean gestational age at diagnosis was 27.5 +/- 6.4 gestational weeks. The average termination of pregnancy was at 35 +/- 5 gestational weeks. In 43.4% of cases there were no major structural defects associated with the facial defect. The most commonly associated structural alterations were cerebral, cardiac, and limb abnormalities. Karyotyping was performed in only 57 cases, and was abnormal in 25. CONCLUSIONS: Structural ultrasound should be performed on all pregnant women between weeks 18 and 24 for detection of major craniofacial defects. Where defects are found, a thorough review of other structures should be carried out to determine whether the defects are syndromic. A systematic and multidisciplinary approach is essential to providing the best care and appropriate advice to parents.