He-Feng Huang

General imprinting status is stable in assisted reproduction–conceived offspring

OBJECTIVEnTo evaluate whether the genomic imprinting status of assistant reproductive technology (ART)-conceived offspring is stable.nnnDESIGNnProspective clinical observational study.nnnSETTINGnInxa0vitro fertilization (IVF) center, university-affiliated teaching hospital.nnnPATIENT(S)nSixty ART-conceived babies (30 IVF and 30 intracytoplasmic sperm injection [ICSI]) and 60 naturally conceived babies.nnnINTERVENTION(S)nCollection of umbilical cord blood and peripheral blood samples.nnnMAIN OUTCOME MEASURE(S)nExpression profile was examined by microarray and real-time reverse-transcription polymerase chain reaction (PCR), allele-specific expression was studied by direct sequencing after PCR, and DNA methylation status was investigated by sodium bisulfite sequencing.nnnRESULT(S)nHierarchic clustering demonstrated no obvious clustering between the ART- and naturally conceived offspring, suggesting similar genomic imprinting expression between the two groups. Three differentially expressed genes were identified in ART-conceived offspring, with PEG10 and L3MBTL up-regulated and PHLDA2 down-regulated. Allele-specific expression of the differentially expressed imprinted genes was maintained in the majority of the ART- and naturally conceived offspring. However, in one ICSI case, monoallelic expression of L3MBTL was disrupted and all CpGs were completely unmethylated. These were not inherited from the parents.nnnCONCLUSION(S)nThe global profile of imprinting is stable in children conceived through ART. However, imprinting of a few specific imprinted genes may be vulnerable in a fraction of ART-conceived children.

Bisphenol A Exposure May Induce Hepatic Lipid Accumulation via Reprogramming the DNA Methylation Patterns of Genes Involved in Lipid Metabolism.

Accumulating evidence suggests a role of bisphenol A (BPA) in metabolic disorders. However, the underlying mechanism is still unclear. Using a mouse BPA exposure model, we investigated the effects of long-term BPA exposure on lipid metabolism and the underlying mechanisms. The male mice exposed to BPA (0.5u2009μg BPA /kg/day, a human relevant dose) for 10 months exhibited significant hepatic accumulation of triglycerides and cholesterol. The liver cells from the BPA-exposed mice showed significantly increased expression levels of the genes related to lipid synthesis. These liver cells showed decreased DNA methylation levels of Srebf1 and Srebf2, and increased expression levels of Srebf1 and Srebf2 that may upregulate the genes related to lipid synthesis. The expression levels of DNA methyltransferases were decreased in BPA-exposed mouse liver. Hepa1-6 cell line treated with BPA showed decreased expression levels of DNA methyltransferases and increased expression levels of genes involved in lipid synthesis. DNA methyltransferase knockdown in Hepa1-6 led to hypo-methylation and increased expression levels of genes involved in lipid synthesis. Our results suggest that long-term BPA exposure could induce hepatic lipid accumulation, which may be due to the epigenetic reprogramming of the genes involved in lipid metabolism, such as the alterations of DNA methylation patterns.

Cardiovascular and metabolic profiles of offspring conceived by assisted reproductive technologies: a systematic review and meta-analysis

OBJECTIVEnTo evaluate cardiovascular and metabolic features of offspring conceived by inxa0vitro fertilization/intracytoplasmic sperm injection (IVF-ICSI).nnnDESIGNnLiterature review and meta-analysis.nnnSETTINGnNot applicable.nnnPATIENT(S)nOffspring from IVF-ICSI versus natural conception.nnnINTERVENTION(S)nNone.nnnMAIN OUTCOME MEASURE(S)nSystolic and diastolic blood pressure (SBP and DBP), cardiovascular function, body mass index (BMI), and lipid and glucose profiles.nnnRESULT(S)nWe included 19 studies that had recruited 2,112 IVF-ICSI and 4,096 naturally conceived offspring, ranging from childhood to early adulthood. The blood pressure levels of IVF-ICSI offspring were statistically significantly higher than those of naturally conceived offspring (weighted mean differences and confidence intervals: 1.88xa0mm Hg [95% CI, 0.27, 3.49] for SBP and 1.51xa0mm Hg [95% CI, 0.33, 2.70] for DBP). In addition, cardiac diastolic function was suboptimal and vessel thickness was higher among IVF-ICSI offspring. Compared with the metabolism of naturally conceived offspring, IVF-ICSI offspring displayed comparable BMI, lower low-density lipoprotein cholesterol levels, and higher fasting insulin levels.nnnCONCLUSION(S)nChildren conceived by IVF-ICSI manifested a minor yet statistically significant increase in blood pressure without the clustering of increased BMI or impaired lipid metabolism by early adulthood. Our findings indicate a risk of cardiovascular disease among IVF-ICSI offspring, which calls for longer-term follow-ups and further investigation.

G546A polymorphism of growth differentiation factor-9 contributes to the poor outcome of ovarian stimulation in women with diminished ovarian reserve

The growth differential factor-9 (GDF-9) gene, an oocyte-specific factor, was screened in 106 Chinese women with diminished ovarian reserve (DOR), and three single-nucleotide polymorphisms, c.G169A, c.C447T and c.G546A, were detected. We found GDF-9 c.G546A, but not c.G169A or c.C447T, to be correlated with the poor ovarian stimulation and in vitro fertilization outcomes in women with DOR.

Leptin down-regulates γ-ENaC expression: a novel mechanism involved in low endometrial receptivity

OBJECTIVEnTo examine epithelial Na(+) channel (ENaC) expression in endometrium of overweight/obese women with polycystic ovary syndrome (PCOS) during the window of implantation, and to explore the mechanism linking leptin-mediated reduction of γ-ENaC to low endometrial receptivity.nnnDESIGNnControlled, prospective, clinical, experimental study.nnnSETTINGnUniversity-based infertility center.nnnPATIENT(S)nBlood and endometrium samples were collected from 12 control women and 12 overweight/obese PCOS patients. Pregnancy outcomes were obtained from 245 women with male-factor infertility (533 cycles) and 57 infertile women with PCOS (120 cycles) who underwent intrauterine insemination.nnnINTERVENTION(S)nHuman endometrial biopsies.nnnMAIN OUTCOME MEASURE(S)nExpression of ENaC mRNA and protein in endometrium.nnnRESULT(S)nThe expression of γ-ENaC decreased in the secretory phase endometrium of PCOS patients who showed increased serum leptin levels. In cultured endometrial cells (Ishikawa cells), leptin dose-dependently down-regulated the expression of γ-ENaC and reduced the JAr spheroid attachment rate, which could be blocked by knockdown of STAT3, a signal in the pathway of leptin receptor activation. The overweight/obese PCOS patients with increased serum leptin levels showed a significantly increased biochemical pregnancy rate, suggesting that high leptin might attenuate endometrial receptivity and increase very early pregnancy loss.nnnCONCLUSION(S)nHigh serum leptin may reduce endometrial receptivity by activating the STAT3 signal pathway and down-regulating γ-ENaC expression in the endometrium. These results provide valuable new insights into the molecular mechanisms linking abnormal ENaC gene expression to early pregnancy loss in overweight/obese PCOS patients.

Cryoprotectants up-regulate expression of mouse oocyte AQP7, which facilitates water diffusion during cryopreservation

OBJECTIVEnTo investigate the effects of cryoprotectants on the expression of AQP7 in oocytes.nnnDESIGNnExperimental animal study.nnnSETTINGnUniversity-based research laboratory.nnnANIMAL(S)nAdult female C57BL/6J mice.nnnINTERVENTION(S)nIn metaphase II (MII) oocytes obtained from adult female C57BL/6J mice and from donations by fertile women, the mouse oocytes were treated with human tubal fluid medium containing 8% ethylene glycol (EG), 9.5% dimethylsulfoxide (DMSO), and 0.5 M sucrose, respectively; 293T cells transfected with GFP-hAQP7 expression vector were treated with the same solutions.nnnMAIN OUTCOME MEASURE(S)nAQP7 expression in oocytes examined by reverse-transcriptase-nested polymerase chain reaction and immunofluorescence, changes in the volume of mouse oocytes treated with different solutions calculated to determine their permeability to water, and survival rates of vitrified oocytes.nnnRESULT(S)nAQP7 is expressed in human and mouse oocytes. Cryoprotectants, including EG, DMSO, and sucrose, up-regulated AQP7 expression in mouse oocytes and 293T cells transfected with GFP-hAQP7 expression vector. Compared with other cryoprotectants, DMSO stimulated higher expression of AQP7, and this was associated with faster cell volume recovery and lower survival rates of vitrified oocytes.nnnCONCLUSION(S)nDMSO up-regulates AQP7 expression in mouse oocytes more than EG. This may facilitate water diffusion and reduce the time for oocytes to reach osmotic balance with the cryoprotectant solution during cryopreservation.

Altered DNA methylation in neonates born large-for-gestational-age is associated with cardiometabolic risk in children

Background Infants being born Large-for-gestational-age (LGA) are prone to developing cardiometabolic disease. However, the underlying mechanisms remain unclear. Results Clinical investigation showed that children born LGA had significantly higher serum level of total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-c), and insulin, ratio of TC/high-density lipoprotein-cholesterol (HDL-c) compared to children born appropriate for gestational age (AGA). Birth weight (BW) was positively correlated to TC, LDL-c, and the ratio of TC/HDL in serum. Genome-wide DNA methylation analyzed in umbilical cord blood of controls and macrosomia cases. We identified 3459 methylation variable positions (MVPs) achieving genome-wide significance (adjusted P-value < 0.05) with methylation differences of ≥ 5%. A total of 327 MVPs were filtered by methylation differences of ≥ 7% located within an island, which mapped to 213 genes. Function analysis using Ingenuity Pathway Analysis showed 16 genes enriched in “cardiovascular disease”. Four genes included contributed to hyperlipidemia. Materials And Methods Fifty-eight children aged 3–6 years born LGA and 123 subjects born AGA were enrolled. Anthropometric parameters and blood pressure (BP) were measured, and metabolic assessment was performed in all subjects. Genome-wide DNA methylation in umbilical blood was assayed by the 450K BeadChip in six AGA and six macrosomia newborns. Conclusions Our data indicate that excess birth weight may increase the risk of lipid dysfunction in children aged 3–6 years. It might through reprogramming a group of genes correlated to cardiovascular disease. The genes identified in this study might be potential biomarker for cardiometabolic disease.

Phoenixin-14 concentrations are increased in association with luteinizing hormone and nesfatin-1 concentrations in women with polycystic ovary syndrome

BACKGROUNDnPolycystic ovary syndrome (PCOS) is commonly characterized by obesity, insulin resistance (IR), hyperandrogenemia and hirsutism. Following the reported relationship between phoenixin-14 and gonadotropin production in rat hypothalamic-pituitary-gonadal axis, the present study was designed to investigate the circulating concentrations of phoenixin-14 and their associations with the concentrations of sex hormones including luteinizing hormone (LH), follicular stimulating hormone (FSH), estradiol (E2), progesterone (P4) and total testosterone (TT) in PCOS patients.nnnMETHODSnA total of 41 women with diagnosed PCOS using Rotterdam criteria and 37 healthy individuals were enrolled in the study.nnnRESULTSnSerum phoenixin-14 concentration in PCOS patients (n=41) was 0.515±0.044ng/ml, significantly higher than that in healthy controls (0.289±0.046ng/ml, n=37). PCOS patients had higher serum LH, dehydroepiandrosterone and fasting blood glucose concentrations, and higher index of homeostasis model of assessment-IR than those in healthy women. Correlation analysis showed significantly positive correlations of phoenixin-14 with LH, FSH, TT, P4, BMI and nesfatin-1 concentrations, and significantly negative correlations with E2 and serum insulin (FSI) concentrations, respectively.nnnCONCLUSIONSnCompared to control women, PCOS patients had significantly increased serum phoenixin-14, LH and androgen concentrations. The positive correlations of phoenixin-14 concentrations with LH and TT concentrations suggest a possible role of phoenixin-14 in the development of PCOS.

Hypertriglyceridemia in female rats during pregnancy induces obesity in male offspring via altering hypothalamic leptin signaling

Maternal obesity influence the childs long-term development and health. Though, the mechanism concerned in this process is still uncertain. In the present study, we explored whether overfeeding of a high-fat diet during pregnancy in female rats altered metabolic phenotypes in an F1 generation and authenticated the contribution of hypothalamic leptin signaling. Leptin responsiveness and the number of immunopositive neurons for phosphorylated signal transducer and activator transcription 3 (pSTAT3) were analyzed. Neuropeptide Y in the arcuate nucleus of the hypothalamus and in nucleus tractus solitaries was examined. Triglycerides and leptin levels were increased in the high-fat diet mother. The number of neuropeptide Y positive cell bodies and neurons was significantly increased in the high-fat diet-F1 offspring (HDF-F1) as compared to Chow-F1. Leptin administration significantly decreased the food intake and increased the pSTAT3 expression levels in neurons in the arcuate nucleus of Chow-F1. However, leptin did not show any effect on food intake and had a reduced effect on pSTAT3 expression levels in neurons in the arcuate nucleus of HDF-F1. From the present domino effect, we conclude that mothers exposed to high-fat diet during pregnancy may pass the obese phenotype to the succeeding generation via altering hypothalamic leptin signaling.Maternal obesity influence the childs long-term development and health. Though, the mechanism concerned in this process is still uncertain. In the present study, we explored whether overfeeding of a high-fat diet during pregnancy in female rats altered metabolic phenotypes in an F1 generation and authenticated the contribution of hypothalamic leptin signaling. Leptin responsiveness and the number of immunopositive neurons for phosphorylated signal transducer and activator transcription 3 (pSTAT3) were analyzed. Neuropeptide Y in the arcuate nucleus of the hypothalamus and in nucleus tractus solitaries was examined. Triglycerides and leptin levels were increased in the high-fat diet mother. The number of neuropeptide Y positive cell bodies and neurons was significantly increased in the high-fat diet-F1 offspring (HDF-F1) as compared to Chow-F1. Leptin administration significantly decreased the food intake and increased the pSTAT3 expression levels in neurons in the arcuate nucleus of Chow-F1. However, leptin did not show any effect on food intake and had a reduced effect on pSTAT3 expression levels in neurons in the arcuate nucleus of HDF-F1. From the present domino effect, we conclude that mothers exposed to high-fat diet during pregnancy may pass the obese phenotype to the succeeding generation via altering hypothalamic leptin signaling.

Serum estradiol levels in controlled ovarian stimulation directly affect the endometrium

Previous studies have shown that increasing estradiol concentrations had a toxic effect on the embryo and were deleterious to embryo adhesion. In this study, we evaluated the physiological impact of estradiol concentrations on endometrial cells to reveal that serum estradiol levels probably targeted the endometrium in controlled ovarian hyperstimulation (COH) protocols. An attachment model of human choriocarcinoma (JAr) cell spheroids to receptive-phase endometrial epithelial cells and Ishikawa cells treated with different estradiol (10−9u2009M or 10−7u2009M) concentrations was developed. Differentially expressed protein profiling of the Ishikawa cells was performed by proteomic analysis. Estradiol at 10−7u2009M demonstrated a high attachment rate of JAr spheroids to the endometrial cell monolayers. Using iTRAQ coupled with LC–MS/MS, we identified 45 differentially expressed proteins containing 43 significantly upregulated and 2 downregulated proteins in Ishikawa cells treated with 10−7u2009M estradiol. Differential expression of C3, plasminogen and kininogen-1 by Western blot confirmed the proteomic results. C3, plasminogen and kininogen-1 localization in human receptive endometrial luminal epithelium highlighted the key proteins as possible targets for endometrial receptivity and interception. Ingenuity pathway analysis of differentially expressed proteins exhibited a variety of signaling pathways, including LXR/RXR activation pathway and acute-phase response signaling and upstream regulators (TNF, IL6, Hmgn3 and miR-140-3p) associated with endometrial receptivity. The observed estrogenic effect on differential proteome dynamics in Ishikawa cells indicates that the human endometrium is the probable target for serum estradiol levels in COH cycles. The findings are also important for future functional studies with the identified proteins that may influence embryo implantation.