Shuping Han

Pre-Pregnancy Body Mass Index in Relation to Infant Birth Weight and Offspring Overweight/Obesity: A Systematic Review and Meta-Analysis

Background Overweight/obesity in women of childbearing age is a serious public-health problem. In China, the incidence of maternal overweight/obesity has been increasing. However, there is not a meta-analysis to determine if pre-pregnancy body mass index (BMI) is related to infant birth weight (BW) and offspring overweight/obesity. Methods Three electronic bibliographic databases (MEDLINE, EMBASE and CINAHL) were searched systematically from January 1970 to November 2012. The dichotomous data on pre-pregnancy overweight/obesity and BW or offspring overweight/obesity were extracted. Summary statistics (odds ratios, ORs) were used by Review Manager, version 5.1.7. Results After screening 665 citations from three electronic databases, we included 45 studies (most of high or medium quality). Compared with normal-weight mothers, pre-pregnancy underweight increased the risk of small for gestational age (SGA) (odds ratios [OR], 1.81; 95% confidence interval [CI], 1.76–1.87); low BW (OR, 1.47; 95% CI, 1.27–1.71). Pre-pregnancy overweight/obesity increased the risk of being large for gestational age (LGA) (OR, 1.53; 95% CI, 1.44–1.63; and OR, 2.08; 95% CI; 1.95–2.23), high BW (OR, 1.53; 95% CI, 1.44–1.63; and OR, 2.00; 95% CI; 1.84–2.18), macrosomia (OR, 1.67; 95% CI, 1.42–1.97; and OR, 3.23; 95% CI, 2.39–4.37), and subsequent offspring overweight/obesity (OR, 1.95; 95% CI, 1.77–2.13; and OR, 3.06; 95% CI, 2.68–3.49), respectively. Sensitivity analyses revealed that sample size, study method, quality grade of study, source of pre-pregnancy BMI or BW had a strong impact on the association between pre-pregnancy obesity and LGA. No significant evidence of publication bias was observed. Conclusions Pre-pregnancy underweight increases the risk of SGA and LBW; pre-pregnancy overweight/obesity increases the risk of LGA, HBW, macrosomia, and subsequent offspring overweight/obesity. A potential effect modification by maternal age, ethnicity, gestational weight gain, as well as the role of gestational diseases should be addressed in future studies.

Trends in Overweight and Obesity among Children and Adolescents in China from 1981 to 2010: A Meta-Analysis

Background Overweight/obesity is a serious public health problem that affects a large part of the world population across all age and racial/ethnic groups. However, there has not been a meta-analysis of the prevalence of childhood and adolescent overweight/obesity in China during the past 30 years. Methods The China National Knowledge Infrastructure and Wanfang DATA, MEDLINE, EMBASE and Cumulative Index to Nursing and Allied Health Literature were searched for relevant studies published between January 1970 and June 2012. The prevalence of overweight/obesity over time was pooled using Stata/SE, version 9. Summary statistics (odds ratios, ORs) were used to compare sex-specific and urban-rural preponderance of overweight/obesity using Review Manager. Results After screening 1326 papers, we included 35 papers (41 studies), most of medium quality. The prevalence of overweight/obesity increased from 1.8% (95% confidence interval [CI], 0.4%–3.1%) and 0.4% (95% CI, −0.1% to −0.8%) respectively in 1981–1985 to 13.1% (95% CI, 11.2%–15.0%) and 7.5% (95% CI, 6.6%–8.4%) respectively in 2006–2010. The average annual increase was 8.3% and 12.4% respectively. Boys were more likely to be overweight/obese than girls (OR, 1.36; 95% CI, 1.24–1.49 and OR, 1.68; 95% CI, 1.52–1.86 respectively). The prevalence of overweight/obesity was higher in urban areas than in rural areas (OR, 1.66; 95% CI, 1.54–1.79 and OR, 1.97; 95% CI, 1.68–2.30 respectively). For age-specific subgroup analyses, both overweight and obesity increased more rapidly in the toddler stage than in other developmental stages. Sensitivity analyses showed that sample-size differences, study quality, overweight/obesity criteria and geographical distribution affected overweight/obesity prevalence. Conclusions Toddlers and urban boys were at particularly high risk; the prevalence in these groups increased more rapidly than in their counterparts. Public health prevention strategies are urgently needed to modify health behaviors of children and adolescents and control overweight/obesity in China.

Genetic Polymorphisms in Adipokine Genes and the Risk of Obesity: A Systematic Review and Meta‐Analysis

Polymorphisms in adipokine genes, such as leptin (LEP), leptin receptor (LEPR), resistin (RETN), adiponectin (ADIPOQ), interleukin‐1β (IL‐1β), IL‐6 (IL‐6), and tumor necrosis factor‐α (TNF‐α) may be involved in the development of obesity. We conducted a systematic review of published evidence on the association between different adipokine genes and the risk of obesity. Librarian‐designed searches of PubMed and HuGeNet, review of reference lists from published reviews and content expert advice identified potentially eligible studies. The genotyping information and polymorphisms of different adipokine genes, numbers of genotyped cases and controls and frequencies of genotypes were extracted from 48 eligible studies included in this review. Twenty‐one polymorphisms each associated with obesity in at least one study were identified. Polymorphisms in the adipokine genes, LEP, LEPR, and RETN were not associated with obesity susceptibility, whereas ADIPOQ G276T (T vs. G: odds ratio (OR), 1.59; 95% confidence interval (CI), 1.39–1.81), IL‐1β C3953T (CC vs. CT+TT: OR, 1.61; 95% CI, 1.18–2.20), and TNF‐α G308A (GG vs. GA+AA: OR, 1.19; 95% CI, 1.02–1.39) polymorphisms were associated with an increased risk of obesity. The IL‐6 G174C polymorphism was also associated obesity when using allelic comparisons, the recessive genetic model and the dominant genetic model with OR (95% CI) of 1.95 (1.37–2.77), 1.44 (1.15–1.80), and 1.36 (1.16–1.59), respectively. No significant evidence of publication bias was present. However, these “null” results were underpowered due to a small pooled sample size, and analysis of additional case‐control studies with larger sample sizes should provide further clarifications.

Identification of maternal serum microRNAs as novel non-invasive biomarkers for prenatal detection of fetal congenital heart defects.

BACKGROUND Congenital heart defects (CHD) are the most common form of malformation during embryonic development. Circulating miRNAs have recently been shown to serve as diagnostic/prognostic biomarkers in patients with cancers. Our current study focused on the altered expression of maternal serum miRNAs and their correlation with fetal CHD. METHODOLOGY/PRINCIPLE FINDINGS We systematically performed SOLiD sequencing followed by individual quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assays to identify and validate the expression of maternal serum miRNAs at 18-22 weeks of gestation. Four miRNAs (miR-19b, miR-22, miR-29c and miR-375) were found to be significantly up-regulated in pregnant women with fetal CHD, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.79, 0.671, 0.767 and 0.693, respectively. Furthermore, the combination of the four miRNAs using multiple logistic regression analysis showed a larger AUC (0.813) that was more efficient for the early detection of fetal CHD. CONCLUSIONS/SIGNIFICANCE We identified and validated a class of four maternal serum miRNAs which could act as novel non-invasive biomarkers for the prenatal detection of fetal CHD.

Effects of miR - 19b Overexpression on Proliferation, Differentiation, Apoptosis and Wnt/β-Catenin Signaling Pathway in P19 Cell Model of Cardiac Differentiation In Vitro

MicroRNA (miR)-19b is part of the miR-17–92 cluster associated with cardiac development. Here, we investigated the effects of overexpressing miR-19b on proliferation, differentiation, apoptosis, and regulation of the Wnt/β-catenin signaling pathway in the multipotent murine P19 cell line that can be induced to undergo cardiogenesis. P19 cells were transfected with the miR-19b plasmid or empty vector, and miR-19b overexpression was verified by Quantitative Real-Time PCR (qPCR). The miR-19b or vector control stable cell lines were selected using Blasticidin S HCl, and their proliferation, cell cycle, and apoptosis levels were analyzed using the Cell Counting Kit-8 and flow cytometry. P19 cell differentiation markers, apoptosis-related genes (bax, bcl-2), and Wnt/β-catenin signaling pathway-related genes were detected by qPCR, the corresponding proteins by Western blot. Expression of the Wnt pathway and differentiation marker proteins was also verified by immunofluorescence. Morphological changes associated with apoptosis were observed by electron microscopy and Hoechst staining. On the basis of these results, we demonstrated that miR-19b overexpression promoted proliferation and differentiation but inhibited apoptosis in P19 cells; Wnt and β-catenin expressions were decreased, while that of GSK3β was increased with miR-19b overexpression. Overexpression of miR-19b inhibited activation of the Wnt/β-catenin signaling pathway in P19 cells, which may regulate cardiomyocyte differentiation. Our findings may bring new insights into the mechanisms underlying cardiac diseases and suggest that miR-19b is a potential new therapeutic target for cardiovascular diseases.

microRNA expression profiling of the developing mouse heart

microRNAs (miRNAs) play an important role in regulating normal organ physiology and development. Many miRNAs show spatially and temporally restricted expression patterns during embryogenesis and organogenesis. This study aimed to characterize the miRNA profile of the fetal mouse heart at 4 key time-points [embryonic day (E)12.5, E14.5, E16.5 and E18.5] in its development, by performing a sequencing by oligonucleotide ligation and detection (SOLiD) miRNA screen. The 4 time-points were designated as groups M1 (E18.5), M2 (E16.5), M3 (E14.5) and M4 (E12.5). miRNAs found to have consistent fold-changes of >2.0) between the 4 time-points were selected for further analysis. Ten miRNAs (mmu-miR-23b, mmu-miR-24, mmu-miR-23a, mmu-miR-375, mmu-miR-29a, mmu-miR-93, mmu-miR-21, mmu-miR-25, mmu-let-7b and mmu-miR-27b) that were the most highly expressed in the 4 groups, including the percentage >1% of total read counts, were identified. No miRNA was consistently downregulated or upregulated. There were 16 differentially expressed miRNAs between the later development group (M1+M2) and the early development group (M3+M4), which were validated by quantitative real-time PCR. Several members of the let-7 miRNA cluster (mmu-let-7a/7d/7e/7f) were upregulated in the later development group compared with the early development group. A network analysis of the predicted targets of mmu-let-7a/7d/7e/7f identified 5 target genes (FOXP1, TBX5, HAND1, AKT2 and PPARGC1A), known to be involved in cardiac development. Therefore, this study identified several miRNAs that are abundantly expressed in the developing heart, several of which are differentially expressed in the 4 time-points studied. Findings of this analysis may thus clarify the mechanisms of normal heart development and provide a physiological basis for future studies on congenital heart disease.

Potential role of maternal serum microRNAs as a biomarker for fetal congenital heart defects

Congenital heart defects (CHD) are the most common form of major birth defect, affecting almost 1% of live births. These defects place a significant economic burden on the National Health Service and on the psychological wellbeing of affected families. The early screening and identification of neonates with CHD could reduce morbidity and mortality by allowing proactive medical treatment and parental counseling about options during pregnancy, including termination. Fetal echocardiography is the principal screening tool for the identification of CHD, but its accuracy mainly depends on the skill and experience of the operator. Various biomarkers of screening for fetal CHD are currently available, such as nuchal translucency (NT), β-hCG and PAPP-A; however, these are non-specific indexes with high incidences of false positive results. Certain specific microRNAs (miRNAs) of cardiogenesis have been identified, which correlate positively with placental miRNA expression. These miRNAs of placental origin can be detected in maternal peripheral blood. Therefore, we postulate that these maternal serum miRNAs may be a potential biomarker for fetal CHD.

Overexpression of miR-19b impairs cardiac development in zebrafish by targeting ctnnb1.

Background: MicroRNAs are broadly accepted as crucial regulators of cardiovascular development, and dysregulation of their expression has been linked to cardiac disease. MicroRNA cluster miR-17-92 has been implicated in cardiac development and function, yet its defined mechanisms of action in this context are uncertain. Here, we focused on miR-19b, a key component of the miR-17-92 cluster proven to induce cardiomyocyte proliferation in vitro. We aimed to identify the biological significance of miR-19b in cardiac development and its underlying molecular mechanism of action in vivo. Methods: We micro-injected zebrafish embryos with different concentrations (0, 2, 4 and 8 μm) of miR-19b mimics or a negative control, and assessed the embryo malformation rate, mortality rate, hatching rate and heart abnormalities at 72 hours post-fertilization (72 hpf). Results: We found that overexpression of miR-19b impacted left-right symmetry and cardiac development of zebrafish embryos, characterized by pericardial edema, slower heart rate and cardiac looping defects in a dose-dependent manner. Moreover, several important signaling molecules in the Wnt signaling pathway were abnormally expressed, suggesting that overexpression of miR-19b induces the inhibition of the Wnt signaling pathway by directly targeting ctnnb1. Interestingly, the deformed cardiac phenotype was partially rescued by treatment with the GSK3β inhibitor lithium chloride. Conclusion: Our findings suggest that miR-19b regulates laterality development and heart looping in zebrafish embryos by targeting ctnnb1.

miR-30c regulates proliferation, apoptosis and differentiation via the Shh signaling pathway in P19 cells

MicroRNAs (miRNAs) are small, non-coding single-stranded RNAs that suppress protein expression by binding to the 3′ untranslated regions of their target genes. Many studies have shown that miRNAs have important roles in congenital heart diseases (CHDs) by regulating gene expression and signaling pathways. We previously found that miR-30c was highly expressed in the heart tissues of aborted embryos with ventricular septal defects. Therefore, this study aimed to explore the effects of miR-30c in CHDs. miR-30c was overexpressed or knocked down in P19 cells, a myocardial cell model that is widely used to study cardiogenesis. We found that miR-30c overexpression not only increased cell proliferation by promoting cell entry into S phase but also suppressed cell apoptosis. In addition, we found that miR-30c inhibited dimethyl sulfoxide-induced differentiation of P19 cells. miR-30c knockdown, in contrast, inhibited cell proliferation and increased apoptosis and differentiation. The Sonic hedgehog (Shh) signaling pathway is essential for normal embryonic development. Western blotting and luciferase assays revealed that Gli2, a transcriptional factor that has essential roles in the Shh signaling pathway, was a potential target gene of miR-30c. Ptch1, another important player in the Shh signaling pathway and a transcriptional target of Gli2, was downregulated by miR-30c overexpression and upregulated by miR-30c knockdown. Collectively, our study revealed that miR-30c suppressed P19 cell differentiation by inhibiting the Shh signaling pathway and altered the balance between cell proliferation and apoptosis, which may result in embryonic cardiac malfunctions.

Circulating LncRNAs as Novel, Non-Invasive Biomarkers for Prenatal Detection of Fetal Congenital Heart Defects

Objectives: To explore the clinical value of circulating long non-coding RNAs (lncRNAs) as biomarkers to predict fetal congenital heart defects (CHD) in pregnant women. Methods: Differential expression of lncRNAs isolated from the plasma of pregnant women with typical fetal CHD or healthy controls was analyzed by microarray. Gene ontology (GO), pathway and network analysis were performed to study the function of the lncRNAs. Differentially expressed lncRNAs were validated in plasma samples from 62 pregnant women with typical CHD and 62 matched controls by RT-PCR. The sensitivity and specificity of each lncRNA in the diagnosis of fetal CHD was determined by ROC curve analysis. Results: Microarray analysis identified 3694 up-regulated and 3919 down-regulated (fold change ≥2.0) lncRNAs. The top ten significantly differentially expressed, CHD-associated lncRNAs were validated by RT-PCR. Five significantly up-regulated or down-regulated lncRNAs were identified: ENST00000436681, ENST00000422826, AA584040, AA709223 and BX478947 with the AUC of ROC curves calculated as 0.892, 0.817, 0.755, 0.882 and 0.886, respectively. Conclusions: Specific lncRNAs aberrantly expressed in the plasma of pregnant women with typical fetal CHD may play a key role in the development of CHD and may be used as novel biomarkers for prenatal diagnosis of fetal CHD.