Search

Abstract Centromere pairing is crucial for synapsis in meiosis. This study delves into the Skp1-Cullin1-F-box protein (SCF) E3 ubiquitin ligase complex, specifically focusing on F-box protein 47 (FBXO47), in mouse meiosis. Here, we revealed that FBXO47 is localized at the centromere and it regulates centromere pairing cooperatively with SKP1 to ensure proper synapsis in pachynema. The absence of FBXO47 causes defective centromeres, resulting in incomplete centromere pairing, which leads to corruption of SC at centromeric ends and along chromosome axes, triggering premature dissociation of chromosomes and pachytene arrest. FBXO47 deficient pachytene spermatocytes exhibited drastically reduced SKP1 expression at centromeres and chromosomes. Additionally, FBXO47 stabilizes SKP1 by down-regulating its ubiquitination in HEK293T cells. In essence, we propose that FBXO47 collaborates with SKP1 to facilitate centromeric SCF formation in spermatocytes. In summary, we posit that the centromeric SCF E3 ligase complex regulates centromere pairing for pachynema progression in mice.

Abstract Histone lysine crotonylation, an evolutionarily conserved modification differing from acetylation, exerts pivotal control over diverse biological processes. Among these are gene transcriptional regulation, spermatogenesis, and cell cycle processes. However, the dynamic changes and functions of histone crotonylation in preimplantation embryonic development in mammals remain unclear. Here, we show that the transcription coactivator P300 functions as a writer of histone crotonylation during embryonic development. Depletion of P300 results in significant developmental defects and dysregulation of the transcriptome of embryos. Importantly, we demonstrate that P300 catalyzes the crotonylation of histone, directly stimulating transcription and regulating gene expression, thereby ensuring successful progression of embryo development up to the blastocyst stage. Moreover, the modification of histone H3 lysine 18 crotonylation (H3K18cr) is primarily localized to active promoter regions. This modification serves as a distinctive epigenetic indicator of crucial transcriptional regulators, facilitating the activation of gene transcription. Together, our results propose a model wherein P300-mediated histone crotonylation plays a crucial role in regulating the fate of embryonic development.

Endochondral ossification is the process by which cartilage is mineralized into bone, and is essential for the development of long bones. Osteocalcin (OCN), a protein abundant in bone matrix, also exhibits high expression in chondrocytes, especially hypertrophic chondrocytes, while its role in endochondral ossification remains unclear. Utilizing a new CRISPR/Cas9-mediated bglap–bglap2 deficiency (OCNem) mouse model generated in our laboratory, we provide the first evidence of OCN’s regulatory function in chondrocyte differentiation and endochondral ossification. The OCNem mice exhibited significant delays in primary and secondary ossification centers compared to wild-type mice, along with increased cartilage length in growth plates and hypertrophic zones during neonatal and adolescent stages. These anomalies indicated that OCN deficiency disturbed endochondral ossification during embryonic and postnatal periods. Mechanism wise, OCN deficiency was found to increase chondrocyte differentiation and postpone vascularization process. Furthermore, bone marrow mesenchymal stromal cells (BMSCs) from OCNem mice demonstrated an increased capacity for chondrogenic differentiation. Transcriptional network analysis implicated that BMP and TGF-β signaling pathways were highly affected in OCNem BMSCs, which is closely associated with cartilage development and maintenance. This elucidation of OCN’s function in chondrocyte differentiation and endochondral ossification contributes to a more comprehensive understanding of its impact on skeletal development and homeostasis.

Abstract Background Metabolic homeostasis is closely related to early impairment of cell fate determination and embryo development. The protein kinase mechanistic target of rapamycin (mTOR) is a key regulator of cellular metabolism in the body. Inhibition of mTOR signaling in early embryo causes postimplantation development failure, yet the mechanisms are still poorly understood. Methods Pregnancy mice and preimplantation mouse embryo were treated with mTOR inhibitor in vivo and in vitro respectively, and subsequently examined the blastocyst formation, implantation, and post-implantation development. We used immunofluorescence staining, RNA-Seq smart2, and genome-wide bisulfite sequencing technologies to investigate the impact of mTOR inhibitors on the quality, cell fate determination, and molecular alterations in developing embryos. Results We showed mTOR suppression during preimplantation decreases the rate of blastocyst formation and the competency of implantation, impairs the post implantation embryonic development. We discovered that blocking mTOR signaling negatively affected the transformation of 8-cell embryos into blastocysts and caused various deficiencies in blastocyst quality. These included problems with compromised trophectoderm cell differentiation, as well as disruptions in cell fate specification. mTOR suppression significantly affected the transcription and DNA methylation of embryos. Treatment with mTOR inhibitors increase lysosomal activation and disrupts the organization and dynamics of the actin cytoskeleton in blastocysts. Conclusions These results demonstrate that mTOR plays a crucial role in 8-cell to blastocyst transition and safeguards embryo quality during early embryo development.

Abstract Caseinolytic protease proteolytic subunit (ClpP) and caseinolytic protease X (ClpX) are mitochondrial matrix peptidases that activate mitochondrial unfolded protein response to maintain protein homeostasis in the mitochondria. However, the role of ClpP and ClpX in spermatogenesis remains largely unknown. In this study, we demonstrated the importance of ClpP/ClpX for meiosis and spermatogenesis with two conditional knockout (cKO) mouse models. We found that ClpP/ClpX deficiency reduced mitochondrial functions and quantity in spermatocytes, affected energy supply during meiosis and attenuated zygotene-pachytene transformation of the male germ cells. The dysregulated spermatocytes finally underwent apoptosis resulting in decreased testicular size and vacuolar structures within the seminiferous tubules. We found mTORC1 pathway was over-activated after deletion of ClpP/ClpX in spermatocytes. Long-term inhibition of the mTORC1 signaling via rapamycin treatment in vivo partially rescue spermatogenesis. The data reveal the critical roles of ClpP and ClpX in regulating meiosis and spermatogenesis.

Abstract The patterns of communication among different chondrocyte subtypes in human cartilage degeneration and regeneration help us understand the microenvironment of osteoarthritis and optimize cell-targeted therapies. Here, a single-cell transcriptome dataset of chondrocytes is used to explore the synergistic and communicative patterns of different chondrocyte subtypes. We collected 1600 chondrocytes from 10 patients with osteoarthritis and analyzed the active communication patterns for the first time based on network analysis and pattern recognition at the single-cell level. Manifold learning and quantitative contrasts were performed to analyze conserved and specific communication pathways. We found that ProCs (Proliferative chondrocytes), ECs (Effector chondrocytes), preHTCs (Prehypertrophic chondrocytes), HTCs (Hypertrophic chondrocytes), and FCs (Fibrocartilage chondrocytes) are more active in incoming and outgoing signaling patterns, which is consistent with studies on their close functional cooperation. Among them, preHTCs play multiple roles in chondrocyte communication, and ProCs and preHTCs have many overlapping pathways. These two subtypes are the most active among all chondrocyte subtypes. Interestingly, ECs and FCs are a pair of “mutually exclusive” subtypes, of which ECs are predominant in incoming patterns and FCs in outgoing patterns. The active signaling pathways of ECs and FCs largely do not overlap. COLLAGEN and LAMININ are the main pivotal pathways, which means they are very important in the repair and expansion of joint homeostasis. Notably, only preHTCs assume multiple roles (including sender, receiver, mediator, and influencer) and are involved in multiple communication pathways. We have examined their communication patterns from the perspective of cellular interactions, revealed the relationships among different chondrocyte subtypes, and, in particular, identified a number of active subtypes and pathways that are important for targeted therapy in the osteoarthritic microenvironment. Our findings provide a new research paradigm and new insights into understanding chondrocyte activity patterns in the osteoarthritic microenvironment.

Abstract Obesity has become a global concern because of increasing the risk of many diseases. Alterations in human gut microbiota have been proven to be associated with obesity, yet the mechanism of how the microbiota are altered by high salt diet (HSD) remains obscure. In this study, the changes of Small Intestinal Microbiota (SIM) in obesity-T2DM mice were investigated. High-throughput sequencing was applied for the jejunum microbiota analysis. Results revealed that high salt intake (HS) could suppress the body weight (B.W.) in some extent. In addition, significant T2DM pathological features were revealed in high salt-high fat diet (HS-HFD) group, despite of relatively lower food intake. High-throughput sequencing analysis indicated that the F/B ratio in HS intake groups increased significantly (P

Abstract Background The adipokine chemerin regulates adipogenesis and the metabolic function of both adipocytes and liver. Chemerin is elevated in preeclamptic women, and overexpression of chemerin in placental trophoblasts induces preeclampsia-like symptoms in mice. Preeclampsia is known to be accompanied by dyslipidemia, albeit via unknown mechanisms. Here, we hypothesized that chemerin might be a contributor to dyslipidemia. Methods Serum lipid fractions as well as lipid-related genes and proteins were determined in pregnant mice with chemerin overexpression in placental trophoblasts and chemerin-overexpressing human trophoblasts. In addition, a phospholipidomics analysis was performed in chemerin-overexpressing trophoblasts. Results Overexpression of chemerin in trophoblasts increased the circulating and placental levels of cholesterol rather than triglycerides. It also increased the serum levels of lysophosphatidic acid, high-density lipoprotein cholesterol (HDL-C), and and low-density lipoprotein cholesterol (LDL-C), and induced placental lipid accumulation. Mechanistically, chemerin upregulated the levels of peroxisome proliferator-activated receptor g, fatty acid-binding protein 4, adiponectin, sterol regulatory element-binding protein 1 and 2, and the ratio of phosphorylated extracellular signal-regulated protein kinase (ERK)1/2 / total ERK1/2 in the placenta of mice and human trophoblasts. Furthermore, chemerin overexpression in human trophoblasts increased the production of lysophospholipids and phospholipids, particularly lysophosphatidylethanolamine. Conclusions Overexpression of placental chemerin production disrupts trophoblast lipid metabolism, thereby potentially contributing to dyslipidemia in preeclampsia.

Type 2 diabetes (T2DM) is characterized by insulin secretion deficiencies and systemic insulin resistance (IR) in adipose tissue, skeletal muscle, and the liver. Although the mechanism of T2DM is not yet fully known, inflammation and insulin resistance play a central role in the pathogenesis of T2DM. G protein‐coupled receptors (GPCRs) are involved in endocrine and metabolic processes as well as many other physiological processes. GPR50 (G protein‐coupled receptor 50) is an orphan GPCR that shares the highest sequence homology with melatonin receptors. The aim of this study was to investigate the effect of GPR50 on inflammation and insulin resistance in 3T3‐L1 preadipocytes. GPR50 expression was observed to be significantly increased in the adipose tissue of obese T2DM mice, while GPR50 deficiency increased inflammation in 3T3‐L1 cells and induced the phosphorylation of AKT and insulin receptor substrate (IRS) 1. Furthermore, GPR50 knockout in the 3T3‐L1 cell line suppressed PPAR‐γ expression. These data suggest that GPR50 can attenuate inflammatory levels and regulate insulin signaling in adipocytes. Furthermore, the effects are mediated through the regulation of the IRS1/AKT signaling pathway and PPAR‐γ expression.

Abstract Background Maternal gestational diabetes mellitus (GDM) had long-term influences on the health of their children. However, the influences of GDM on the oral microbiota, which was closely related to oral and systemic health in offspring, were less documented. The present study aimed to explore the oral microbiota of neonates born to mothers with GDM is differentially colonized compared with those born to mothers without GDM, and whether any such differences persist to 1 month of age. Methods Oral samples were collected from children of mothers with (n = 20) and without GDM (n = 34) at birth and again at an average age of 1 month. The oral microbiota was characterized by 16S rRNA sequencing (V3-V4). Differences in diversity and composition according to maternal GDM status were assessed, and different metabolic functional pathways and microbial ecological networks were also analyzed. Results Although no significant differences were observed in diversity metrics between GDM and non-GDM groups (P > 0.05), we found significant differences in the taxonomic composition of oral microbiota from phylum to genus level between the two groups, with the GDM group exhibiting less abundance of Veillonella in both “Day 1” (P

Endometriosis is a common gynecological disease, characterized by the presence of endometrial-like lesions outside the uterus. This debilitating disease causes chronic pelvic pain and infertility with limited therapeutics. Chemerin is a secretory protein that acts on CMKLR1 (Chemokine-Like Receptor 1) to execute functions vital for immunity, adiposity, and metabolism. Abnormal chemerin/CMKLR1 axis underlies the pathological mechanisms of certain diseases including cancer and inflammatory diseases, but its role in endometriosis remains unknown. Herein, our results showed that chemerin and CMKLR1 are up-regulated in endometriotic lesions by analyzing the human endometriosis database and murine model. Knockdown of chemerin or CMKLR1 by shRNA led to mesenchymal-epithelial transition (MET) along with compromised viability, migration, and invasion of hEM15A cells. Most importantly, 2-(α-naphthoyl) ethyltrimethylammonium iodide (α-NETA), a small molecule antagonist for CMKLR1, was evidenced to exhibit profound anti-endometriosis effects (anti-growth, anti-mesenchymal features, anti-angiogenesis, and anti-inflammation) in vitro and in vivo. Mechanistically, α-NETA exhibited a dual inhibition effect on PI3K/Akt and MAPK/ERK signaling pathways in hEM15A cells and murine endometriotic grafts. This study highlights that the chemerin/CMKLR1 signaling axis is critical for endometriosis progression, and targeting this axis by α-NETA may provide new options for therapeutic intervention.

Preeclampsia, a clinical syndrome mainly characterized by hypertension and proteinuria, with a worldwide incidence of 3–8% and high maternal mortality, is a risk factor highly associated with maternal and offspring cardiovascular disease. However, the etiology and pathogenesis of preeclampsia are complicated and have not been fully elucidated. Obesity, immunological diseases and endocrine metabolic diseases are high-risk factors for the development of preeclampsia. Effective methods to treat preeclampsia are lacking, and termination of pregnancy remains the only curative treatment for preeclampsia. The pathogenesis of preeclampsia include poor placentation, uteroplacental malperfusion, oxidative stress, endoplasmic reticulum stress, dysregulated immune tolerance, vascular inflammation and endothelial cell dysfunction. The notion that placenta is the core factor in the pathogenesis of preeclampsia is still prevailing. G protein-coupled receptors, the largest family of membrane proteins in eukaryotes and the largest drug target family to date, exhibit diversity in structure and function. Among them, the secretin/adhesion (Class B) G protein-coupled receptors are essential drug targets for human diseases, such as endocrine diseases and cardiometabolic diseases. Given the great value of the secretin/adhesion (Class B) G protein-coupled receptors in the regulation of cardiovascular system function and the drug target exploration, we summarize the role of these receptors in placental development and preeclampsia, and outlined the relevant pathological mechanisms, thereby providing potential drug targets for preeclampsia treatment.

BackgroundImmunotherapy has achieved remarkable efficacy in treating oesophageal squamous cell carcinoma (ESCC). However, this treatment has limited efficacy in some patients. An increasing number of evidence suggested that immune cells within the tumour microenvironment (TME) are strongly related to immunotherapy response and patient prognosis. Thus, the landscape of immune cell infiltration (ICI) in ESCC needs to be mapped.MethodsIn the study, the ICI pattern in 206 cases of ESCC was characterised by two algorithms, namely, CIBERSORT and single-sample gene set enrichment analysis (ssGSEA). The ICI score of each specimen was calculated by principal component analysis (PCA) according to ICI signature genes A (ICISGA) and B (ICISGB). The prognostic difference was evaluated by using the Kaplan–Meier method. The related pathways of ICI score were investigated by applying gene set enrichment analysis (GSEA). The R packages of ‘regplot’, ‘timeROC’ and ‘rms’ were applied for the construction of nomogram model.ResultThree TME subtypes were identified with no prognostic implication. A total of 333 differentially expressed genes (DEGs) among immune subtypes were determined, among which ICISGA and ICISGB were identified. Finally, ICI scores were constructed, and the patients were grouped into high or low ICI score group. Compared with the low ICI score group, the high ICI score group had better prognosis. GSEA revealed that the high ICI score group referred to multiple signalling pathways, including B cell receptor, Fc gamma R-mediated phagocytosis, NOD-like receptor and TGF-β signalling pathways. In addition, the nomogram model was constructed to evaluate 1-, 3- and 5-year probability of death in an ESCC patient. The ROC and calibration curves indicated that the model has a good discrimination ability.ConclusionWe depicted a comprehensive ICI landscape in ESCC. ICI score may be used as a predictor of survival rate, which may be helpful for guiding immunotherapy in the future.

Chemerin is an adipokine that regulates metabolism in pregnancy. An elevation of serum chemerin level is associated with pregnancy complications. Consistently, we demonstrated that the chemerin expression was increased in placenta of preeclamptic patients at deliveries. The G protein-coupled receptor chemokine-like receptor 1 (CMKLR1) mediates the actions of chemerin. The functions of the chemerin-CMKLR1 axis in maintaining pregnancy are still unknown. In this study, we demonstrated that CMKLR1 was expressed in the decidual natural killer (dNK) cells and chorionic villi of human. Chemerin suppressed the proliferation of the dNK cells in vitro. Specific antagonist of CMKLR1, α-Neta abolished the suppressive effect of spent medium from chemerin-treated dNK cells culture on extravillous trophoblast invasion. Activation of the chemerin-CMKLR1 axis promoted fusion and differentiation of human cytotrophoblast to syncytiotrophoblast in vitro. We generated Cmklr1 knockout mice and showed that the Cmklr1 deficiency negatively affected pregnancy outcome in terms of number of implantation sites, litter size and fetal weight at birth. Histologically, the Cmklr1 deficiency impaired formation of the syncytiotrophoblast layer II, induced enlargement of the maternal lacunae in the labyrinth, increased the diameter of the spiral arteries and increased trophoblast invasion in the decidua. The Cmklr1 deficient placenta also displayed an increased number of dNK cells and serum IL-15 level. In summary, the chemerin-CMKLR1 axis regulated placental development and spiral artery remodeling in early pregnancy.

Mitochondria are highly dynamic organelles and their activity is known to be regulated by changes in morphology via fusion and fission events. However, the role of mitochondrial dynamics on cellular differentiation remains largely unknown. Here, we explored the molecular mechanism of mitochondrial fusion during spermatogenesis by generating an Mfn2 (mitofusin 2) conditional knock-out (cKO) mouse model. We found that depletion of MFN2 in male germ cells led to disrupted spermatogenesis and meiosis during which the majority of Mfn2 cKO spermatocytes did not develop to the pachytene stage. We showed that in these Mfn2 cKO spermatocytes, oxidative phosphorylation in the mitochondria was affected. In addition, RNA-Seq analysis showed that there was a significantly altered transcriptome profile in the Mfn2 deficient pachytene (or pachytene-like) spermatocytes, with a total of 262 genes up-regulated and 728 genes down-regulated, compared with wild-type (control) mice. Pathway enrichment analysis indicated that the peroxisome proliferator-activated receptor (PPAR) pathway was altered, and subsequent more detailed analysis showed that the expression of PPAR α and PPAR γ was up-regulated and down-regulated, respectively, in the MFN2 deficient pachytene (or pachytene-like) spermatocytes. We also demonstrated that there were more lipid droplets in the Mfn2 cKO cells than in the control cells. In conclusion, our study demonstrates a novel finding that MFN2 deficiency negatively affects mitochondrial functions and alters PPAR pathway together with lipid metabolism during spermatogenesis and meiosis.

The adipokine chemerin has been considered an important regulator of tumor immune surveillance. Chemerin recruits leukocytes through the receptor CMKLR1 to improve clinical outcomes of tumors and overall patient survival, but the role of GPR1 in tumors has not been widely investigated. Here, we found that GPR1 expression is elevated in breast cancer—especially triple-negative breast cancer (TNBC) tissues and cell lines. Herein, we screened a phage display peptide library to identify LRH7-G5, a peptide antagonist that blocks chemerin/GPR1 signaling. This peptide performed as an anticancer agent to suppress the proliferation of the TNBC cell lines MDA-MB-231 and HCC1937 but has little effect on T47D cells. LRH7-G5 treatment significantly blocked tumor growth in a TNBC cell-bearing orthotopic mouse model. Last, our results showed that this peptide’s antitumor role is mediated through the PI3K/AKT signaling pathway. In conclusion, these data collectively suggest that the chemerin receptor GPR1 is a novel target for controlling TNBC progression and establish peptide LRH7-G5 as a new therapeutic agent for suppressing TNBC tumor growth.

Microgravity has been shown to induces many changes in proliferation, differentiation and growth behavior of stem cells. Little is known about the effect of microgravity on hematopoietic differentiation of pluripotent stem cells (PSCs). In this study, we used the random position machine (RPM) to investigate whether simulated microgravity (SMG) allows the induction of hematopoietic stem/progenitor cell (HSPC) derived from human embryonic stem cells (hESCs) in vitro. The results showed that SMG facilitates hESCs differentiate to HSPC with more efficient induction of CD34+CD31+ hemogenic endothelium progenitors (HEPs) on day 4 and CD34+CD43+ HSPC on day 7, and these cells shows an increased generation of functional hematopoietic cells in colony-forming unit assay when compared with normal gravity (NG) conditions. Additionally, we found that SMG significantly increased the total number of cells on day 4 and day 7 which formed more 3D cell clusters. Transcriptome analysis of cells identified thousands of differentially expressed genes (DEGs) between NG and SMG. DEGs down-regulated were enriched in the axonogenesis, positive regulation of cell adhesion, cell adhesion molecule and axon guidance, while SMG resulted in the up-regulation of genes were functionally associated with DNA replication, cell cycle, PI3K-Akt signaling pathway and tumorigenesis. Interestingly, some key gene terms were enriched in SMG, like hypoxia and ECM receptor interaction. Moreover, HSPC obtained from SMG culture conditions had a robust ability of proliferation in vitro. The proliferated cells also had the ability to form erythroid, granulocyte and monocyte/macrophage colonies, and can be induced to generate macrophages and megakaryocytes. In summary, our data has shown a potent impact of microgravity on hematopoietic differentiation of hPSCs for the first time and reveals an underlying mechanism for the effect of SMG on hematopoiesis development.

As a multifaceted adipokine, chemerin has been found to perform functions vital for immunity, adiposity, and metabolism through its three known receptors (chemokine-like receptor 1, CMKLR1; G-protein-coupled receptor 1, GPR1; C-C motif chemokine receptor-like 2, CCRL2). Chemerin and the cognate receptors are also expressed in the hypothalamus, pituitary gland, testis, ovary, and placenta. Accumulating studies suggest that chemerin participates in normal reproduction and underlies the pathological mechanisms of certain reproductive system diseases, including polycystic ovary syndrome (PCOS), preeclampsia, and breast cancer. Herein, we present a comprehensive review of the roles of the chemerin system in multiple reproductive processes and human reproductive diseases, with a brief discussion and perspectives on future clinical applications.

Hyperandrogenism is a key pathological feature of polycystic ovarian syndrome (PCOS). Excess androgen can lead to PCOS-like cell hypertrophy in the ovaries and adipose tissue of rodents. Here, we established a dihydrotestosterone (DHT)-induced hyperandrogenic mouse model to analyze the differences in gene expression and signaling pathways of the ovaries and gonad fat pads of mice treated with or without DHT by RNA microarray analysis. From the results, we focused on the overlapping differentially expressed gene—Col6a5—and the major differentially enriched signaling pathway—lipid metabolism. We employed DHT-induced mouse ovarian stromal cell, adipogenic 3T3-L1 cell and hepatic cell line NCTC1469 models to investigate whether androgens directly mediate lipid accumulation and hypertrophy. We found that DHT increased lipid droplet accumulation in ovarian stromal cells and adipogenic 3T3-L1 cells but not NCTC1469 cells. DHT significantly altered stromal cell cholesterol metabolism and steroidogenesis, as indicated by changes in cholesterol levels and the expression of related genes, but these effects were not observed in 3T3-L1 cells. Moreover, Col6a5 expression was significantly increased in ovaries and gonadal fat pads of DHT-treated mice, and Col6a5 inhibition alleviated DHT-induced excess lipid accumulation and hypertrophy of ovarian stromal cells and adipogenic 3T3-L1 cells, even improved lipid metabolism in overnourished NCTC1469 cells. Our results indicate that Col6a5 plays important roles in the pathogenesis of DHT-induced lipid metabolism disorder and the hypertrophy of ovarian stromal cells and adipocytes.

Osteoprotegerin (OPG) is involved in various biological processes, including bone remodeling, vascular calcification and pancreatic β-cell function. Although some clinical studies have shown an increase in serum OPG level during pregnancy, the role of OPG in gestational diabetes mellitus (GDM) is largely unknown. Therefore, we explored the effect of OPG in metabolic homeostasis during pregnancy. We initially evaluated serum OPG levels using ELISA and western blotting techniques on samples from GDM patients. We also assessed OPG expression levels in maternal mice. We then used blastocysts transduced with lentiviruses capable of trophoblast-specific transgene expression to establish placenta-specific OPG knockdown or overexpression mouse models for functional and mechanistic investigation after embryo transplantation. We found that OPG expression was positively associated with GDM in clinical samples, and OPG levels were significantly increased in GDM patient sera and term placenta. Serum OPG was significantly increased in maternal compared to non-pregnant mice, and expression levels of OPG were the highest in placenta compared with other organs, including bone, liver and pancreas. OPG was also significantly increased in pregnant mice fed a high-fat diet (HFD). Placenta-specific OPG knockdown induced glucose intolerance, decreased β-cell proliferation and decreased serum insulin levels, whereas placenta-specific OPG overexpression promoted glucose tolerance and enhanced β-cell proliferation, which increased serum insulin production and decreased fetal weight in HFD-feeding pregnant mice. Placenta-derived OPG (pl-OPG) regulated glucose homeostasis during pregnancy via enhancement of β-cell proliferation, which suggests a potential therapeutic application of OPG for GDM.

Background/Aims: Gestational diabetes mellitus (GDM) is a common complication of pregnancy, but the mechanisms underlying the disorders remain unclear. The study aimed to identify mRNA and long non-coding RNA (lncRNA) profiles in placenta and gonadal fat of pregnant mice fed a high-fat diet and to investigate the transcripts and pathways involved in the development of gestational diabetes mellitus. Methods: Deep and broad transcriptome profiling was performed to assess the expression of mRNAs and lncRNAs in placenta and gonadal fat from 3 mice fed an HFD and chow during pregnancy. Then, differentially expressed mRNAs and lncRNAs were validated by quantitative real-time PCR. The function of the differentially expressed mRNAs was determined by pathway and Gene Ontology (GO) analyses, and the physical or functional relationships between the lncRNAs and the corresponding mRNAs were determined. Results: Our study revealed that 82 mRNAs and 52 lncRNAs were differentially expressed in the placenta of mice fed an HFD during pregnancy, and 202 mRNAs and 120 lncRNAs were differentially expressed in gonadal fat. GO and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed differentially expressed mRNAs of placenta were closely related to extracellular matrix interactions, digestion, adhesion, and metabolism, whereas the differentially expressed mRNAs in adipose tissue were related to metabolic and insulin signalling pathways. The gene network demonstrated that Actg2, Cnfn, Muc16, Serpina3k, NONMMUT068202, and NONMMUT068203, were the core of the network in placental tissue, and the genes Tkt, Acss2, and Elovl6 served as the core of the network in gonadal fat tissue. Conclusion: These newly identified key genes and pathways in mice might provide valuable information regarding the pathogenesis of GDM and might be used to improve early diagnosis, prevention, drug design, and clinical treatment.

Abstract Background Polycystic ovary syndrome (PCOS) is a complex genetic disease with multifarious phenotypes. Many researches use dehydroepiandrosterone (DHEA) to induce PCOS in pubertal mouse models. The aim of this study was to investigate the role of GPR1 in dehydroepiandrosterone (DHEA)-induced hyperandrogenized mice. Methods Prepubertal C57BL/6 mice (25 days of age) and Gpr1-deficient mice were each divided into two groups and injected daily with sesame oil with or without DHEA (6 mg/100 g) for 21 consecutive days. Hematoxylin and eosin (H&E) staining was performed to determine the characteristics of the DHEA-treated ovaries. Real-time PCR was used to examine steroid synthesis enzymes gene expression. Granulosa cell was cultured to explore the mechanism of DHEA-induced, GPR1–mediated estradiol secretion. Results DHEA treatment induced some aspects of PCOS in wild-type mice, such as increased body weight, elevated serum testosterone, increased number of small, cystic, atretic follicles, and absence of corpus luteum in ovaries. However, Gpr1 deficiency significantly attenuated the DHEA-induced weight gain and ovarian phenotype, improving steroidogenesis in ovaries and estradiol synthesis in cultured granulosa cells, partially through mTOR signaling. Conclusions In conclusion, Gpr1 deficiency leads to the improvement of steroid synthesis in mice hyperandrogenized with DHEA, indicating that GPR1 may be a therapeutic target for DHEA-induced hyperandrogenism.

Oncolytic virus (OV) as a promising therapeutic agent can selectively infect and kill tumor cells with naturally inherited or engineered properties. Considering the limitations of OVs monotherapy, combination therapy has been widely explored. MEK inhibitor (MEKi) Trametinib is an FDA-approved kinase inhibitor indicated for the treatment of tumors with BRAF V600E or V600K mutations. In this study, the oncolytic activity in vitro and anti-tumor therapeutic efficacy in vivo when combined with oHSV and MEKi Trametinib were investigated. We found: (1) Treatment with MEKi Trametinib augmented oHSV oncolytic activity in BRAF V600E-mutated tumor cells. (2) Combination treatment with oHSV and MEKi Trametinib enhanced virus replication mediated by down-regulation of STAT1 and PKR expression or phosphorylation in BRAF V600E-mutated tumor cells as well as BRAF wt/KRAS-mutated tumor cells. (3) A remarkably synergistic therapeutic efficacy was shown in vivo for BRAF wt/KRAS-mutated tumor models, when a combination of oHSV including PD-1 blockade and MEK inhibition. Collectively, these data provide some new insights for clinical development of combination therapy with oncolytic virus, MEK inhibition, and checkpoint blockade for BRAF or KRAS-mutated tumors.

The mammalian ovary has two main functions—producing mature oocytes for fertilization and secreting hormones for maintaining the ovarian endocrine functions. Both functions are vital for female reproduction. Primordial follicles are composed of flattened pre-granulosa cells and a primary oocyte, and activation of primordial follicles is the first step in follicular development and is the key factor in determining the reproductive capacity of females. The recent identification of the phosphatidylinositol 3 kinase (PI3K)/phosphatase and tensin homolog deleted on chromosome 10 (PTEN) signaling pathway as the key controller for follicular activation has made the study of primordial follicle activation a hot research topic in the field of reproduction. This review systematically summarizes the roles of the PI3K/PTEN signaling pathway in primordial follicle activation and discusses how the pathway interacts with various other molecular networks to control follicular activation. Studies on the activation of primordial follicles have led to the development of methods for the in vitro activation of primordial follicles as a treatment for infertility in women with premature ovarian insufficiency or poor ovarian response, and these are also discussed along with some practical applications of our current knowledge of follicular activation.

Maintenance of healthy bone quality and quantity requires a well-coordinated balance between bone formation by osteoblasts and bone resorption by osteoclasts. Chemerin is a novel adipokine with known functions such as regulating immunity and energy homeostasis through activation of chemokine-like receptor 1 (CMKLR1). G protein-coupled receptor 1 (GPR1) is the second mammalian chemerin receptor with similar binding affinity as CMKLR1. In male GPR1–/– mice, a phenotype with significantly low bone mineral density was observed. We hypothesise that GPR1 might participate the process of bone remodelling. In this study, we investigated the role of GPR1 in regulating bone mass maintenance in male mice, and for the first time, revealed that GPR1–/– male mice manifested seriously trabecular bone loss and lower serum testosterone levels compared to the wild type animals. Accordingly, the mRNA expression of biomarkers related to both osteoblast [collagen type I alpha 2 (Col1A2), osteocalcin (OCN)] and osteoclast [tartrate-resistant acid phosphatase (TRAP), Cathepsin K, NFATc1] were significantly decreased or increased in GPR1–/– mice relative to the wild type, respectively. However, other osteogenic markers, Osterix and ALP levels, were increased. Microcomputed tomography scanning and histological analyses proved that there was a myriad of trabecular bone loss in GPR1–/– mice. In the meantime, GPR1–/– mice presented a significant decrease in serum testosterone level. Taken together, these findings suggested that chemerin–GPR1 signalling might be directly or indirectly communicated with testosterone synthesis on bone turnover regulation. Further detailed studies are required to unveil how chemerin–GPR1 participates in bone metabolism. The translational potential of this article: More studies and knowledge about GPR1 regulating function in bone turnover might supply a novel therapeutic target for osteoporosis in the future.

Endometriosis is a common gynecological disease, characterized by the presence of endometrial-like lesions outside the uterus. This debilitating disease causes chronic pelvic pain and infertility with limited therapeutics. Chemerin is a secretory protein that acts on CMKLR1 (Chemokine-Like Receptor 1) to execute functions vital for immunity, adiposity, and metabolism. Abnormal chemerin/CMKLR1 axis underlies the pathological mechanisms of certain diseases including cancer and inflammatory diseases, but its role in endometriosis remains unknown. Herein, our results showed that chemerin and CMKLR1 are up-regulated in endometriotic lesions by analyzing the human endometriosis database and murine model. Knockdown of chemerin or CMKLR1 by shRNA led to mesenchymal-epithelial transition (MET) along with compromised viability, migration, and invasion of hEM15A cells. Most importantly, 2-(α-naphthoyl) ethyltrimethylammonium iodide (α-NETA), a small molecule antagonist for CMKLR1, was evidenced to exhibit profound anti-endometriosis effects (anti-growth, anti-mesenchymal features, anti-angiogenesis, and anti-inflammation) in vitro and in vivo. Mechanistically, α-NETA exhibited a dual inhibition effect on PI3K/Akt and MAPK/ERK signaling pathways in hEM15A cells and murine endometriotic grafts. This study highlights that the chemerin/CMKLR1 signaling axis is critical for endometriosis progression, and targeting this axis by α-NETA may provide new options for therapeutic intervention. [ABSTRACT FROM AUTHOR]