Loss of miR-23b/27b/24-1 Cluster Impairs Glucose Tolerance via Glycolysis Pathway in Mice.

Alterations in miRNAs are associated with many metabolic disorders, such as type 2 diabetes (T2DM). The miR-23b/27b/24-1 cluster contains miR-23b, miR-27b, and miR-24-1, which are located within 881 bp on chromosome 9. Studies examining the roles of miR-23b, miR-27b, and miR-24-1 have demonstrated their multifaceted functions in variable metabolic disorders. However, their joint roles in metabolism in vivo remain elusive. To investigate this subject, we constructed miR-23b/27b/24-1 cluster knockout (KO) mice. Compared with wild-type (WT) mice, the KO mice exhibited impaired glucose tolerance, which was accompanied by a reduction in the respiratory exchange rate (RER). These alterations were more noticeable after a high-fat diet (HFD) induction. Hepatic metabolomic results showed decreased expression of reduced nicotinamide adenine dinucleotide (NADH), nicotinamide adenine dinucleotide (NAD), phosphoenolpyruvic acid (PEP), and phosphoric acid, which are involved in the glycolysis pathway. The transcriptomic results indicated that genes involved in glycolysis showed a downregulation trend. qPCR and Western blot revealed that pyruvate kinase (PKLR), the key rate-limiting enzyme in glycolysis, was significantly reduced after the deletion of the miR-23b/27b/24-1 cluster. Together, these observations suggest that the miR-23b/27b/24-1 cluster is involved in the regulation of glucose homeostasis via the glycolysis pathway.

Role of Androgen Receptor for Reconsidering the "True" Polycystic Ovarian Morphology in PCOS.

PURPOSE: Polycystic ovarian morphology (PCOM) is one of the key features of polycystic ovary syndrome (PCOS). The diagnosis of PCOM according to the Rotterdam criteria (≥12 antral follicles per ovary) is debated because of the high prevalence of PCOM in the general population. Androgen receptor (AR) is associated with the PCOS phenotype and might as well play a role during folliculogenesis. This study is aimed to investigate the expression of the AR in PCOS granulosa cells (GCs) and its relationship with the PCOM phenotype. METHODS: 106 PCOS cases and 63 controls were included from the Center for Reproductive Medicine, Shandong University. The diagnosis of PCOS was following the Rotterdam criteria (2003). Total RNA was extracted from GCs retrieved from ovarian stimulation. The expression of AR was amplified by means of quantitative real-time polymerase chain reaction. RESULTS: The AR expression was significantly decreased in PCOS cases, especially in the tPCOM subgroup (≥20 antral follicles per ovary). Correlation analyses showed that AR expression was significantly correlated with serum FSH levels in controls and non-tPCOM. In the tPCOM subgroup, the AR expression was significantly correlated with serum LH levels. Interestingly, the significance of these correlations gradually disappeared as the threshold of antral follicles increased above 24 for PCOM. CONCLUSIONS: AR was differently expressed in PCOS and especially in the tPCOM subtype. The correlation of AR expression with serum FSH and LH might be associated with the number of follicles in PCOM.

RNA-Binding Protein IGF2BP2/IMP2 is a Critical Maternal Activator in Early Zygotic Genome Activation.

A number of genes involved in zygotic genome activation (ZGA) have been identified, but the RNA-binding maternal factors that are directly related to ZGA in mice remain unclear. The present study shows that maternal deletion of Igf  2bp2 (also commonly known as Imp2) in mouse embryos causes early embryonic developmental arrest in vitro at the 2-cell-stage. Transcriptomics and proteomics analyses of 2-cell-stage embryos in mice reveal that deletion of IMP2 downregulates the expression of Ccar1 and Rps14, both of which are required for early embryonic developmental competence. IGF2, a target of IMP2, when added in culture media, increases the proportion of wild-type embryos that develop successfully to the blastocyst stage: from 29% in untreated controls to 65% (50 × 10-9 m IGF2). Furthermore, in an experiment related to embryo transfer, foster mothers receiving IGF2-treated embryos deliver more pups per female than females who receive untreated control embryos. In clinically derived human oocytes, the addition of IGF2 to the culture media significantly enhances the proportion of embryos that develop successfully. Collectively, the findings demonstrate that IMP2 is essential for the regulation and activation of genes known to be involved in ZGA and reveal the potential embryonic development-related utility of IGF2 for animal biotechnology and for assisted reproduction in humans.

The HMGA2-IMP2 Pathway Promotes Granulosa Cell Proliferation in Polycystic Ovary Syndrome.

CONTEXT: The high mobility group AT hook 2 (HMGA2) gene was previously identified in a genome-wide association study as a candidate risk gene that might be related to polycystic ovary syndrome (PCOS). Whether HMGA2 contributes to promoting granulosa cell (GC) proliferation in PCOS remains unknown. OBJECTIVE: We sought to determine whether HMGA2 is involved in the ovarian dysfunction of PCOS and in the mechanism of increased GC proliferation. PATIENTS AND CELLS: mRNA expression was analyzed in ovarian GCs from 96 women with PCOS and 58 healthy controls. Immortalized human GCs (KGN and SVOG cells) were used for the mechanism study. MAIN OUTCOME MEASURES: mRNA expression in ovarian GCs was measured using quantitative RT-PCR, and KGN cells were cultured for proliferation assays after overexpression or knockdown of target genes. Protein expression analysis, luciferase assays, and RNA binding protein immunoprecipitation assays were used to confirm the mechanism study. RESULTS: HMGA2 and IGF2 mRNA binding protein 2 (IMP2) were highly expressed in the GCs of women with PCOS, and the HMGA2/IMP2 pathway promoted GC proliferation. Cyclin D2 and SERPINE1 mRNA binding protein 1 were regulated by IMP2 and were highly expressed in women with PCOS. CONCLUSIONS: The HMGA2/IMP2 pathway was activated in women with PCOS and promoted the proliferation of GCs. This might provide new insights into the dysfunction of GCs in PCOS.

Resveratrol improves in vitro maturation of oocytes in aged mice and humans.

OBJECTIVE: To evaluate the effects of resveratrol on oocyte maturation in aged mice and humans. DESIGN: Experimental laboratory study. SETTING: University-based reproductive medicine center. PATIENT(S): A total of 64 women 38-45 years of age undergoing intracytoplasmic sperm injection (ICSI) and 48-52-week-old female C57BL/6J mice. INTERVENTION(S): In vitro culture in the presence of three different concentrations of resveratrol (0.1, 1.0, and 10 µm) or dimethylsulfoxide. MAIN OUTCOME MEASURE(S): Parameters of oocyte nuclear maturation, fertilization, immunofluorescence intensity of mitochondria, and normal morphology of spindle and chromosome of oocytes undergoing in vitro maturation (IVM) in aged mice and humans; blastocyst formation and levels of SRIT1, CAT, SOD1, and GPX4 gene expressions in aged mice. RESULT(S): Resveratrol at 1.0 µm significantly increased first polar body emission rate in oocytes derived from aged mice and humans, and an increased percentage of fertilization and blastocyst formation was observed in aged mice. In addition, immunofluorescence intensity of mitochondria and normal morphology of spindle and chromosome of oocytes undergoing IVM were notably improved compared with control samples in aged mice and human. Furthermore, the use of resveratrol exhibited enhanced expression patterns of SRIT1, CAT, SOD1, and GPX4 in aged mice. CONCLUSION(S): Resveratrol induced oocyte maturation and blastocyst formation in aged mice, and improved oocyte maturation and quality was examined in aged humans. In conclusion, 1.0 µm resveratrol was the appropriate concentration in IVM medium.

Wilms' Tumor 1 Overexpression in Granulosa Cells Is Associated with Polycystic Ovaries in Polycystic Ovary Syndrome Patients.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a heterogeneous disorder characterized by chronic ovulatory dysfunction, hyperandrogenism, and polycystic ovaries. Wilms' tumor 1 (WT1) encoding a transcription factor involved in the differentiation of granulosa cells (GCs) regulates androgen receptor in the development of male genitalia. However, the expression pattern and possible role of WT1 in ovaries of PCOS patients are still unknown. METHODS: GCs from 95 PCOS patients (PCOS group) and 62 healthy controls (control group) were isolated. The expression of WT1 in GCs was quantified using the reverse transcription-polymerase chain reaction. The correlation between WT1 expression and clinical characteristics was evaluated in PCOS patients. RESULTS: WT1 expression was increased in PCOS patients compared with the normal controls. The expression of WT1 was moderately correlated with testosterone (r = 0.334, p = 0.001) and luteinizing hormone (r = 0.357, p = 0.001) levels and the antral follicle counts (r = 0.337, p = 0.001). CONCLUSIONS: Our study provided novel insights into the relationship between hyperandrogenism and polycystic ovaries of PCOS and WT1.

Integrated microRNA and mRNA signatures in peripheral blood lymphocytes of familial epithelial ovarian cancer.

PURPOSE: Characterization of the genetic landscapes of familial ovarian cancer through integrated analysis of microRNA and mRNA by partial least squares (PLS) and Monte Carlo technique based on genome-wide association studies (GWAS). METHODS: The miRNA and mRNA transcriptional data in familial ovarian cancer were characterized from the Gene Expression Omnibus (GEO) database. The miRNA and mRNA expression profiles in peripheral blood lymphocytes (PBLs) of 74 familial ovarian cancer patients and 47 control subjects were analyzed with the integration of partial least squares (PLS) and Monte Carlo techniques. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were also performed. RESULTS: Total of 16 miRNA-mRNA pairs were identified with the target gene prediction results of miRNAs and mRNAs. An innovated miRNA-mRNA integrated network was constructed in which 6 downregulated miRNAs and 1 upregulated miRNAs were included. KEGG and GO pathway enrichment analysis revealed over-representation of dysregulated miRNAs in various biological processes especially in cancer pathology. Hsa-miR-34b played a pivotal role in this network and interacted with other miRNAs. Hsa-miR-136 and hsa-miR-335 were associated with p53 and Erk1/2 pathways and tumor suppressors, such as PTEN. CONCLUSIONS: The results from this research provide insights on miRNA-mRNA networks and offer new tools for studying transcriptional variants in familial ovarian cancer.

Identification of reference genes for qRT-PCR in granulosa cells of healthy women and polycystic ovarian syndrome patients.

Comparative gene expression analysis by qRT-PCR is commonly used to detect differentially expressed genes in studies of PCOS pathology. Impaired GC function is strongly associated with PCOS pathogenesis, and a growing body of studies has been dedicated to identifying differentially expressed genes in GCs in PCOS patients and healthy women by qRT-PCR. It is necessary to validate the expression stability of the selected reference genes across the tested samples for target gene expression normalization. We examined the variability and stability of expression of the 15 commonly used reference genes in GCs from 44 PCOS patients and 45 healthy women using the GeNorm, BestKeeper, and NormFinder statistical algorithms. We combined the rankings of the three programs to produce a final ranking based on the geometric means of their stability scores. We found that HPRT1, RPLP0, and HMBS out of 15 examined commonly used reference genes are stably expressed in GCs in both controls and PCOS patients and can be used for normalization in gene expression profiling by qRT-PCR. Future gene-expression studies should consider using these reference genes in GCs in PCOS patients for more accurate quantitation of target gene expression and data interpretation.

STMN1 Promotes Progesterone Production Via StAR Up-regulation in Mouse Granulosa Cells.

Stathmin 1 (STMN1) is a biomarker in several types of neoplasms. It plays an important role in cell cycle progression, mitosis, signal transduction and cell migration. In ovaries, STMN1 is predominantly expressed in granulosa cells (GCs). However, little is known about the role of STMN1 in ovary. In this study, we demonstrated that STMN1 is overexpressed in GCs in patients with polycystic ovary syndrome (PCOS). In mouse primary GCs, the overexpression of STMN1 stimulated progesterone production, whereas knockdown of STMN1 decreased progesterone production. We also found that STMN1 positively regulates the expression of Star (steroidogenic acute regulatory protein) and Cyp11a1 (cytochrome P450 family 11 subfamily A member 1). Promoter and ChIP assays indicated that STMN1 increased the transcriptional activity of Star and Cyp11a1 by binding to their promoter regions. The data suggest that STMN1 mediates the progesterone production by modulating the promoter activity of Star and Cyp11a1. Together, our findings provide novel insights into the molecular mechanisms of STMN1 in ovary GC steroidogenesis. A better understanding of this potential interaction between STMN1 and Star in progesterone biosynthesis in GCs will facilitate the discovery of new therapeutic targets in PCOS.

[Prevalence, detection, management, and control of hypertension in the population of Mongolian and Han nationalities with age ≥ 55 years in a pastoral area of Inner Mongolia Autonomous Region].

OBJECTIVE: To know about the status of hypertension among Mongolian and Han aged older than 55 years living in pastoral area of the Inner Mongolia Autonomous Region. METHODS: Stratified sampling method was adopted and 9146 people aged 55 years or older were selected, blood pressure measurement and related information were collected, prevalence, awareness, treatment and control rates of hypertension were analyzed. RESULTS: The hypertension crude prevalence rate of Mongolian and Han subjects was 54.10% (standardized prevalence rate was 53.93%), in which, the Mongolian and Han subjects crude hypertension prevalence rate was 52.96% and 54.73% respectively (standardized prevalence rate was 53.44% and 55.08% respectively), and there was no statistically significant (P = 0.104). Among the male gender, awareness rate, treatment rate and control rate of hypertension was 61.03%, 46.73% and 11.87% respectively. Among the female gender, awareness rate, treatment rate and control rate of hypertension was 67.58%, 56.55% and 14.03% respectively. Among Mongolian and Han subjects, difference of hypertension prevalence of different age groups was statistically significant (P values were 0.032 and 0.000), Among Mongolian subjects, difference of hypertension awareness of different age groups was statistically significant (P = 0.000). Among Han subjects, difference of hypertension awareness rates, treatment rates, and control rates of different age groups were statistically significant (P values were 0.000, 0.047 and 0.043). CONCLUSION: Hypertension prevalence rate among Han and Mongolian people older than 55 years living in pastoral area of Inner Mongolia Autonomous Region is high while the awareness, treatment and control rates of hypertension are rather low.

Resting-state fMRI studies in epilepsy.

Epilepsy is a disease characterized by abnormal spontaneous activity in the brain. Resting-state functional magnetic resonance imaging (RS-fMRI) is a powerful technique for exploring this activity. With good spatial and temporal resolution, RS-fMRI is a promising approach for accurate localization of the focus of seizure activity. Although simultaneous electroencephalogram-fMRI has been performed with patients in the resting state, most studies focused on activation. This mini-review focuses on RS-fMRI alone, including its computational methods and its application to epilepsy.

[A prevalence study on mild cognitive impairment among the elderly populations of Mongolian and Han nationalities in a pastoral area of Inner Mongolia].

OBJECTIVE: To understand the epidemiological characteristics and distribution of mild cognitive impairment (MCI) in elderly populations from Mongolian and Han nationalities living in the pastoral areas of Inner Mongolia Autonomous Region of China. METHODS: According to the MCI clinical diagnostic criteria from Diagnostic and Statistical Manual of Mental Disorders 4th revised edition (DSM-IV) by American Psychiatric Association, the individuals under study were at the age of 55 or over, with Mongolian or Han ethnicities and living in the pastoral area of Inner Mongolia. RESULTS: The crude MCI morbidity rates of Mongolian and Han of the study populations in the pastoral area of Inner Mongolia Autonomous Region of China was 19.48% (1782/9146) and the standardization morbidity was 18.98%. The crude MCI morbidity rates of both Mongolian and Han ethnicities were 17.46% (the standardization morbidity was 16.99%) and 20.60% (the standardization morbidity was 19.98%), respectively. There showed a significant positive correlation between the crude morbidities and age, also significantly increasing with the latter. In the Mongolian population, the morbidity increased from 12.17% at the age 55-59 to 27.78% at 85 while in the Han population, the morbidity increased from 15.50% at the age 55-59 to 23.53% at 85. In both the populations of Mongolian and Han, there was a statistically difference found between the morbidities of MCI (χ2=13.229, P=0.000). The morbidity was higher in Hans than in the Mongolians. However, there was no statistically significant difference noticed between the morbidities of MCI in the Mongolian males and females (χ2=2.376, P=0.123). There was statistically significant difference found between the morbidities of MCI in the Han males and females, with females having higher risk than males (χ2=24.470, P=0.000). CONCLUSION: The morbidity of MCI in the elderly Mongolian and Han populations from the pastoral area of Inner Mongolia Autonomous Region of China was considered to be quite high and correlated to age and gender.

[Effects of recurrent audiogenic seizures on hippocampal structure and seizure behavior of P77PMC rats].

OBJECTIVE: To investigate the functional role of hippocampal mossy fiber sprouting in the pathophysiologic mechanism of initiation and propagation of epilepsy. METHODS: The authors examined hippocampal mossy fiber synaptic reorganization and the changes of hippocampal neurons in P77PMC rats at different stages in the course of recurrent seizures using Timm's method of silver sulfide staining and Nissl staining and observed the effects of recurrent audiogenic seizures (AGSs) on seizure behavior of P77PMC rats. RESULTS: Frequent recurrent AGSs could cause neuronal loss in CA(1) region of hippocampus and hippocampal mossy fiber sprouting got into the inner molecular layer of dentate gyrus in P77PMC rats, and could decrease the latency of IV/V grade of AGSs, increase the durations of AGSs. The mean A of CA(1) region of hippocampus in Nissl staining after 50 times of AGSs was 35.3 +/- 0.8, which was markedly lower than that of the control (44.1 +/- 0.5; F = 333.89, P < 0.001). The mean A of the inner molecular layer of dentate gyrus in Timm's staining after 50 times of AGSs was 49.3 +/- 4.6, which was markedly higher than that of the control (26.8 +/- 1.7; F = 76.83, P < 0.001). After 30 and 50 times of AGSs, the latent periods of IV/V grade of AGSs were 12 +/- 8 (t = 3.805; P < 0.02) and 17 +/- 7 (t = 5.927; P < 0.002) seconds shorter than the initial period of stimulation respectively on average, and the durations of AGSs were 19 +/- 18 (t = 2.644; P < 0.05) and 10 +/- 7 (t = 3.780; P < 0.02) seconds longer. CONCLUSION: Hippocampal mossy fiber sprouting and neuronal loss not only presents in limbic seizure, but also in AGS, the seizure can be initiated in brainstem but rapidly generalized;in AGS-prone rats, recurrent AGSs can cause mossy fiber synaptic reorganization and neuronal loss in hippocampus, and can also enhance seizure susceptibility of P77PMC rats. In the course of recurrent AGSs, enhanced seizure susceptibility happened before hippocampal mossy fiber sprouting. Their temporal relationships indicate that the anatomical changes may be preceded by functional changes of elevated excitability in the brain.