PCSK9 involves in the high-fat diet-induced abnormal testicular function of male mice.

In brief: Impaired spermatogenesis resulting from disturbed cholesterol metabolism due to intake of high-fat diet (HFD) has been widely recognized, however, the role of preprotein invertase subtilin 9 (PCSK9), which is a negative regulator of cholesterol metabolism, has never been reported. This study aims to reveal the role of PCSK9 on spermatogenesis induced by HFD in mice. Abstract: Long-term consumption of a high-fat diet (HFD) is an important factor that leads to impaired spermatogenesis exhibiting poor sperm quantity and quality. However, the mechanism of this is yet to be elucidated. Disrupted cholesterol homeostasis is one of many crucial pathological factors which could contribute to impaired spermatogenesis. As a negative regulator of cholesterol metabolism, preprotein invertase subtilin 9 (PCSK9) mediates low density lipoprotein receptor (LDLR) degradation to the lysosome, thereby reducing the expression of LDLR on the cell membrane and increasing serum low-density lipoprotein cholesterol level, resulting in lipid metabolism disorders. Here, we aim to study whether PCSK9 is a pathological factor for impaired spermatogenesis induced by HFD and the underlying mechanism. To meet the purpose of our study, we utilized wild-type C57BL/6 male mice and PCSK9 knockout mice with same background as experimental subjects and alirocumab, a PCSK9 inhibitor, was used for treatment. Results indicated that HFD induced higher PCSK9 expression in serum, liver, and testes, and serum PCSK9 is negatively correlated with spermatogenesis, while both PCSK9 inhibitor treatment and PCSK9 knockout methodologies ameliorated impaired lipid metabolism and spermatogenesis in mice fed a HFD. This could be due to the overexpression of PCSK9 induced by HFD leading to dyslipidemia, resulting in testicular lipotoxicity, thus activating the Bcl-2-Bax-Caspase3 apoptosis signaling pathway in testes, particularly in Leydig cells. Our study demonstrates that PCSK9 is an important pathological factor in the dysfunction of spermatogenesis in mice induced by HFD. This finding could provide innovative ideas for the diagnosis and treatment of male infertility.

Contribution of high-fat diet-induced PCSK9 upregulation to a mouse model of PCOS is mediated partly by SREBP2.

The incidence of polycystic ovary syndrome (PCOS) due to high-fat diet (HFD) consumption has been increasing significantly. However, the mechanism by which a HFD contributes to the pathogenesis of PCOS has not been elucidated. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key protein that regulates cholesterol metabolism. Our previous study revealed abnormally high PCSK9 levels in serum from patients with PCOS and in serum and hepatic and ovarian tissues from PCOS model mice, suggesting that PCSK9 is involved in the pathogenesis of PCOS. However, the factor that induces high PCSK9 expression in PCOS remains unclear. In this study, Pcsk9 knockout mice were used to further explore the role of PCSK9 in PCOS. We also studied the effects of a HFD on the expression of PCSK9 and sterol regulatory element-binding protein 2 (SREBP2), a regulator of cholesterol homeostasis and a key transcription factor that regulates the expression of PCSK9, and the roles of these proteins in PCOS pathology. Our results indicated HFD may play an important role by inducing abnormally high PCSK9 expression via SREBP2 upregulation. We further investigated the effects of an effective SREBP inhibitor, fatostain, and found that it could reduce HFD-induced PCSK9 expression, ameliorate hyperlipidemia and improve follicular development in PCOS model mice. Our study thus further elucidates the important role of an HFD in the pathogenesis of PCOS and provides a new clue in the prevention and treatment of this disorder.

Progesterone-induced miR-152 interferes with embryonic implantation by downregulating GLUT3 in endometrial epithelium.

To investigate the role of progesterone-induced micro-RNA (miR)-152 in early embryonic development and implantation by regulating GLUT3 in endometrial epithelium, qRT-PCR was used to detect the expression of miR-152, GLUT1, and GLUT3 in the endometrial epithelial cells of female mice. GLUT1 and GLUT3 proteins were detected by immunohistochemical staining in the mouse endometrial epithelium. Bioinformatics prediction associated with a luciferase assay was performed to determine whether GLUT1 and GLUT3 are target genes of miR-152. Specific miR-152 mimics or inhibitors were transfected into the endometrial epithelial cells to, respectively, overexpress or downregulate miR-152. Next, the glucose concentration of uterine fluid was measured by conducting high-performance liquid chromatography in vivo, and the glucose uptake of the endometrial epithelial cells was observed using a fluorometric assay in vitro. Early embryonic development and implantation were also observed after the miR-152 mimics or inhibitors had been transfected. Embryo transfer was observed after the miR-152 mimic transfection. miR-152 was found to directly target and thereby downregulate GLUT3 expression. The expressions of both miR-152 and GLUT3 in the mouse endometrial epithelium had spatiotemporal characteristics on days 1-4 of pregnancy. miR-152 affected the glucose concentration of uterine fluid and the glucose uptake of endometrial epithelial cells. The transfection of specific miR-152 mimics led to impaired embryonic development and implantation. To conclude, in endometrial epithelial cells, progesterone-induced miR-152 downregulates GLUT3 at the posttranscriptional level to maintain a proper glucose concentration in the uterine fluid, which is necessary for early embryonic development and implantation.

[Progesterone-induced microRNA-1a inhibits the proliferation of endometrial epithelial cells].

The aim of the present study was to investigate the effects of progesterone (P4)-induced microRNA-1a (miR-1a) on the proliferation of endometrial epithelial cells (EECs) and the underlying mechanism. In vivo, following subcutaneous injection of estradiol (E2) alone (E2 group) or combined injections of E2 and P4 (E2P4 group) in ovariectomized mice, quantitative real-time PCR (qPCR) was used to check the expression of miR-1a-3p in the directly isolated mouse EECs. The agomir or antagomir specific for miR-1a-3p was injected into one side of the uterine horns of ovariectomized mice pretreated with E2 alone or in combination with P4, and the non-specific control agomir or antagomir was injected into their contralateral horns. Flow cytometry was used to analyze the cell cycle of EECs. Immunohistochemistry (IHC) was used to examine the location and expression of cyclin D2, cyclin E1, and cyclin E2 in the uterine tissue sections. In vitro, primary cultured mouse EECs were pretreated with E2 alone (E2 group) or in combination with P4 (E2P4 group). qPCR was used to detect the expression of miR-1a-3p. Exogenous mimic of miR-1a-3p was transfected into E2-pretreated EECs, and EdU incorporation analysis was used to test the proliferation activity of the EECs. The result of in vivo experiment showed that the expression of miR-1a-3p in E2P4 group was significantly higher than that in E2 group (P < 0.05). The miR-1a-3p agomir arrested cell cycle at G1 to S transition in the mice injected subcutaneously with E2 alone (P < 0.05). Conversely, silencing of miR-1a-3p with transfection of miR-1a-3p antagomir promoted the entry of cells into S phase in the mice injected subcutaneously with both E2 and P4 (P < 0.05). The expressions of cyclin E1 and cyclin E2, except for cyclin D2, in uterine sections were also dramatically reduced by miR-1a-3p overexpression in the uterine epithelium (P < 0.05). In vitro, miR-1a-3p was not expressed in the cells of both E2 and E2P4 groups. The mimic of miR-1a-3p decreased EECs proliferation activity (P < 0.05). These results indicate that P4-induced miR-1a can inhibit the expression of cyclin E1 and cyclin E2, consequently suppressing the proliferation of mouse EECs by arresting cells at G1/S phase.

Relocalisation and activation of integrins induced rapidly by oestrogen via G-protein-coupled receptor 30 in mouse blastocysts.

Integrins are the dominant and final adhesion molecules in the attachment process between the blastocysts and endometrium. It is necessary for oestrogen to rapidly activate mouse blastocysts so that they attach to the endometrial epithelium. Our previous study suggested that oestrogen can rapidly induce an increase in intracellular calcium in mouse blastocysts via G-protein-coupled receptor 30 (GPR30). Thus, we deduced that integrins may be involved in GPR30 mediation of the fast effect of oestrogen on mouse blastocysts in implantation. To prove our hypothesis, we used immunofluorescence staining and in vitro coculture of mouse blastocysts and endometrial epithelial cell line (EECs), Ishikawa cells, in the present study. We found that αv and ß1 integrin clustered in mouse blastocysts, and that ß3 integrin was relocalised to the apical membrane of blastocyst cells when embryos were treated with 1 µM 17ß-estradiol (E2), 1 µM E2 conjugated to bovine serum albumin (E2-BSA) and 1 µM G-1, a specific GPR30 agonist, for 30 min respectively, whereas pretreatment with 1 µM G15, a specific GPR30 antagonist, and 5 µM 1,2-Bis(2-aminophenoxy)ethane-N,N,N'',N''-tetraacetic acid tetrakis (acetoxymethyl ester)(BAPTA/AM), a cellular Ca2+ chelator, blocked the localisation of integrins induced by oestrogen via GPR30 in mouse blastocyst cells. E2, E2-BSA and G-1 increased the fibronectin (FN)-binding activity of integrins in blastocysts, whereas G15 and BAPTA/AM blocked the activation of integrins induced by oestrogen via GPR30 in mouse blastocysts. Inhibition of integrins by Arg-Gly-Asp peptide in blastocysts resulted in their failure to adhere to EECs in vitro, even if oestrogen or G-1 was provided. Together, the results indicate the fast effect of oestrogen via the GPR30 membrane receptor further induces relocalisation and activation of integrins in mouse blastocysts, which play important roles in the adhesion of blastocysts to EECs.

[Estrogen induced rapid increase of intracellular calcium plays important role in the implantation of mouse blastocysts].

OBJECTIVE: To study the roles of the increased intracellular calcium induced rapidly by estrogen in the implantation of mouse blastocysts. METHODS: The mouse blastocysts were collected from the female mice on the pregnant day 4, divided into 3 groups: control, E2-BSA and BAPTA +E2-BSA. Immunofluorescence staining, confocal microscopy, embryo and endometrial epithenial cells co-culture and embryo transfer were used to investigate the effect of increased intracellular calcium induced by E2-BSA on the expression and localization of integrins in blastocysts and their adhesion to endometrial epithenial calls (EECs) and implantation into the endometrium. RESULTS: The increase of intracellular calcium induced rapidly by estrogen could cause the cluster and relocation of integrin av and beta3, and BAPTA might block this effect, the adhesion rate of blastocysts in contol group was 35.5%, BAPTA +E2-BSA group was 26.7% and significantly lower than 65.6% of E2-BSA group (P<0.05), and the implantation rate in BAPTA+E2-BSA group was 11.8%, which was significantly lower than 52.9% of E2-BSA group (P<0.05). CONCLUSION: The rapid increase of intracellular calcium induced by estrogen may cause the relocalization of integrin in blastocysts and their adhesion to ECCs, which is important in the process of implantation.

Expression of aldose reductase in mouse endometrial epithelial cells and its role in sperm capacitation.

The survival, motility and capacitation of sperm in the female reproductive tract are important prerequisites for fertilization. The uterus is the main location for sperm capacitation. One of the most important physiological functions of the endometrial epithelium is to create a suitable uterine environment under the regulation of ovarian hormones, to ensure sperm capacitation. The composition of uterine fluid directly affects sperm capacitation. Fructose is an important component of semen that supports sperm viability and motility. Aldose reductase, a rate-limiting enzyme in the polyol pathway, metabolizes sorbitol and fructose, thereby supplying cells with necessary energy for functional activities. Existing studies have reported the presence aldose reductase in the endometrium, leading us to hypothesize that its expression in endometrial epithelium might promote sperm capacitation by maintaining the uterine environment. Yet, the mechanism of regulation has not been clarified. In this study, we investigated the expression of aldose reductase in mouse endometrial epithelium and its potential role in sperm capacitation. We initially investigated the periodic characteristics of glucose, fructose and sorbitol in uterine fluid. We then studied the temporal and spatial characteristics of aldose reductase in the endometrial epithelium. Next, we examined the effect of aldose reductase on glucose, fructose and sorbitol in uterine fluid. Finally, we explored the effect of aldose reductase on sperm capacitation and fertilization. The results showed that glucose and fructose content in uterine fluid and the expression of aldose reductase fluctuated periodically during physiological periods. Inhibition of aldose reductase in the endometrial epithelium interfered with sperm capacitation and fertilization by reducing the fructose levels in the uterine fluid. To conclude, the aldose reductase-mediated polyol pathway in endometrial epithelial cells is essential to maintain an appropriate fructose environment in the uterine fluid for sperm capacitation and fertilization.

Hyperandrogen-induced polyol pathway flux increase affects ovarian function in polycystic ovary syndrome via excessive oxidative stress.

AIMS: Polycystic ovary syndrome (PCOS) is a common endocrine disorder in the women of childbearing age. It is characterized by hyperandrogenism and abnormal follicular growth and ovulation. The polyol pathway is a glucose metabolism bypass pathway initiated by aldose reductase (ADR). Androgen induces the expression of ADR in the male reproductive tract, which has a general physiological significance for male reproductive function. Here we investigate whether hyperandrogenemia in PCOS leads to increased flux of the polyol pathway in ovarian tissue, which in turn affects follicular maturation and ovulation through oxidative stress. MAIN METHODS: We used clinical epidemiological methods to collect serum and granulosa cells from clinical subjects for a clinical case-control study. At the same time, cell biology and molecular biology techniques were used to conduct animal and cell experiments to further explore the mechanism of hyperandrogen-induced ovarian polyol pathway hyperactivity and damage to ovarian function. KEY FINDINGS: Here, we find that hyperandrogenism of PCOS can induce the expression of ovarian aldose reductase, which leads to the increase of the polyol pathway flux, and affects ovarian function through excessive oxidative stress. SIGNIFICANCE: Our research has enriched the pathological mechanism of PCOS and may provide a new clue for the clinical treatment of PCOS.

[PP2A is involved in the inhibitory effect of progesterone on proliferation of mouse endometrial epithelial cells].

OBJECTIVE: To study the effect of protein phosphatase 2A (PP2A) in the negative regulation of progesterone on the proliferation of mouse endometrial epithelial cells (EECs). METHODS: Mouse EECs were isolated and cultured in vitro, which were divided into four groups when they grown to confluence: control group (P4) was treated with 1 micromol/L progesterone only, group A, B and C were treated respectively with 1 micromol/L progesterone and different concentrations of okadaic acid (5 nmol/L, 10 nmol/L and 20 nmol/L). After 24 h, the numbers of cells in different phases of the cell cycle were counted with flow cytometry. RESULTS: The effect of OA on mouse EECs was concentration-dependent. Compared with control group of P4, the change of cell cycle procession in group A was not obvious. Lower proportion of cells in G1 and G2/M phase and higher proportion of cells in S phase in group B, higher proportion of cells in G1 and S phase and lower proportion of cells in G2/M phase in group C were observed. CONCLUSION: Adequate dose OA inhibiting PP2A could release the inhibitory effect of progesterone on proliferation of mouse EECs obviously, this suggested that PP2A was involved in the inhibitory effect of progesterone on proliferation of EECs by influencing the process of cell cycle.

Exploring the association between epilepsy and depression: A systematic review and meta-analysis.

OBJECTIVE: This study offers meta-analytic data on the potential association between epilepsy and depression especially for the prevalence of depression in epilepsy or vice versa. METHODS: The relevant studies were searched and identified from nine electronic databases. Studies that mentioned the prevalence and/or incidence of epilepsy and depression were included. Hand searches were also included. The search language was English and the search time was through May 2022. Where feasible, random-effects models were used to generate pooled estimates. RESULTS: After screening electronic databases and other resources, 48 studies from 6,234 citations were included in this meta-analysis. The period prevalence of epilepsy ranged from 1% to 6% in patients with depression. In population-based settings, the pooled period prevalence of depression in patients with epilepsy was 27% (95% CI, 23-31) and 34% in clinical settings (95% CI, 30-39). Twenty studies reported that seizure frequency, low income, unemployment of the patients, perception of stigma, anxiety, being female, unmarried status, disease course, worse quality of life, higher disability scores, and focal-impaired awareness seizures were risk factors for depression. CONCLUSION: Our study found that epilepsy was associated with an increased risk of depression. Depression was associated with the severity of epilepsy.

Expression of SGLT1 in the Mouse Endometrial Epithelium and its Role in Early Embryonic Development and Implantation.

Many functional activities of endometrium epithelium are energy consuming which are very important for maintaining intrauterine environment needed by early embryonic development and establishment of implantation window. Glucose is a main energy supplier and one of the main components of intrauterine fluid. Obviously, glucose transports in endometrium epithelium involve in for these activities but their functions have not been elucidated. In this research, we observed a spatiotemporal pattern of sodium glucose transporter 1 (SGLT1) expression in the mouse endometrium. We also determined that progesterone can promote the expression of SGLT1 in the mouse endometrial epithelium in response to the action of oestrogen. Treatment with the SGLT1 inhibitor phlorizin or small interfering RNA specific for SGLT1 (SGLT1-siRNA) altered glucose uptake in primary cultured endometrial epithelial cells, which exhibited reduced ATP levels and AMPK activation. The injection of phlorizin or SGLT1-siRNA into one uterine horn of each mouse on day 2 of pregnancy led to an increased glucose concentration in the uterine fluid and decreased number of harvested normal blastocysts and decreased expression of integrin αVß3 in endometrial epithelium and increased expression of mucin 1 and lactoferrin in endometrial epithelium and the uterine homogenates exhibited activated AMPK, a decreased ATP level on day 4, and a decreased number of implantation sites on day 5. In embryo transfer experiments, pre-treatment of the uterine horn with phlorizin or SGLT1-siRNA during the implantation window led to a decreased embryo implantation rate on day 5 of pregnancy, even when embryos from normal donor mice were used. In conclusion, SGLT1, which participates in glucose transport in the mouse endometrial epithelium, inhibition and/or reduced expression of SGLT1 affects early embryo development by altering the glucose concentration in the uterine fluid. Inhibition and/or reduced expression of SGLT1 also affects embryo implantation by influencing energy metabolism in epithelial cells, which consequently influences implantation-related functional activities.

The Effects of Altered Endometrial Glucose Homeostasis on Embryo Implantation in Type 2 Diabetic Mice.

Type 2 diabetes mellitus (T2DM) is a disease characterized by hyperglycemia resulting from insulin resistance. In recent years, the incidence of T2DM has been increasing. Women with T2DM often suffer from infertility and early miscarriage; however, the underlying mechanisms remain unclear. Insulin is the most important regulatory hormone of glycogen metabolism. In addition, 5' adenosine monophosphate-activated protein kinase (AMPK) is an important regulator of glycogen metabolism. Patients with T2DM have inhibited AMPK expression in the liver, which leads to impaired glucose metabolism. However, the role of AMPK in endometrial glycogen metabolism has not been reported. In this study, a mouse model of T2DM was established to investigate whether altered endometrial glucose metabolism affects early embryo implantation. Metformin and insulin were used for therapy; the resulting changes to glycogen metabolism and embryo implantation were examined. The results indicate that the concentrations of glycogen decreased significantly in T2DM mice, resulting in insufficient energy supplies for proper endometrial function, and thereby impeding embryonic implantation. Interestingly, endometrial AMPK was not found to be overactivated. Insulin treatment was found to partially resolve the embryo implantation defects in T2DM mice. Metformin improved blood glucose but did not have a significant effect on local endometrial glucose metabolism. This study explored the changes in endometrial glucose metabolism in T2DM mouse, and the effects of these changes on embryo implantation. We found that insulin, but not metformin, significantly resolved embryo implantation problems. These findings will help to increase our understanding of the pathomechanisms of infertility and early miscarriage in women with T2DM.

GLUT4 in Mouse Endometrial Epithelium: Roles in Embryonic Development and Implantation.

GLUT4 is involved in rapid glucose uptake among various kinds of cells to contribute to glucose homeostasis. Prior data have reported that aberrant glucose metabolism by GLUT4 dysfunction in the uterus could be responsible for infertility and increased miscarriage. However, the expression and precise functions of GLUT4 in the endometrium under physiological conditions remain unknown or controversial. In this study, we observed that GLUT4 exhibits a spatiotemporal expression in mouse uterus on pregnant days 1-4; its expression especially increased on pregnant day 4 during the window of implantation. We also determined that estrogen, in conjunction with progesterone, promotes the expression of GLUT4 in the endometrial epithelium in vivo or in vitro. GLUT4 is an important transporter that mediates glucose transport in endometrial epithelial cells (EECs) in vitro or in vivo. In vitro, glucose uptake decreased in mouse EECs when the cells were treated with GLUT4 small interfering RNA (siRNA). In vivo, the injection of GLUT4-siRNA into one side of the mouse uterine horns resulted in an increased glucose concentration in the uterine fluid on pregnant day 4, although it was still lower than in blood, and impaired endometrial receptivity by inhibiting pinopode formation and the expressions of leukemia inhibitory factor (LIF) and integrin ανß3, finally affecting embryonic development and implantation. Overall, the obtained results indicate that GLUT4 in the endometrial epithelium affects embryo development by altering glucose concentration in the uterine fluid. It can also affect implantation by impairing endometrial receptivity due to dysfunction of GLUT4.

Impact of Disturbed Glucose Homeostasis Regulated by AMPK in Endometrium on Embryo Implantation in Diabetes Mice.

The incidence of diabetes in women of childbearing age has been increasing recently and implantation failure and early abortion are important reasons for infertility in diabetic women. Glycogen synthesis and decomposition are the cores of glucose homeostasis in endometrium and AMPK is activated when cellular energy consumption increases. Embryo implantation is a complex process required huge energy. Yet the changes of glucose metabolism in endometrium and its impact on embryo implantation in diabetic women are still unclear. In this research, we established diabetic pregnancy mice model by intraperitoneal injecting streptozotocin on pregnant day 1. We first tested the changes of endometrial glucose homeostasis and embryo implantation. Next, we demonstrated abnormal activation of AMPK in the endometrium of diabetic mice and its affecting endometrial glucose homeostasis. Finally, we compared the endometrial glucose homeostasis and embryo implantation outcome in diabetic pregnant mice treated with insulin or insulin combined with metformin. The results indicated that there was disturbed glucose homeostasis associated with excessive activation of AMPK in endometrium of diabetic pregnant mice. AMPK inhibitor improved the over-activation of AMPK pathway in the endometrium, meanwhile, partially corrected the abnormal glycogen metabolism and improved the implantation. Insulin improved the disorder of endometrial glucose homeostasis and implantation of diabetic mice. Our research explores the causes of high abortion and infertility rate in diabetic women which is to provide a therapeutic reference for patients with diabetes complicated with infertility and early abortion.

[Mechanisms of nongenomic effect of 17beta-estradiol on human spermatozoa].

OBJECTIVE: To study the mechanisms of nongenomic effect of 17beta-estradiol on human spermatozoa. METHODS: The intracellular calcium ([Ca2+]i) in the spermatozoa was measured by flow cytometry after the spermatozoa was treated with the inhibitors of trans-membrane signaling transduction pathways and impermeable 17beta-estradiol (E2-BSA). Western blot was used to detect the activation of the signal proteins after the spermatozoa was treated with 1 x 10(-6) mol/L E2-BSA and tamoxifen, an estrogen receptor inhibitor. RESULTS: Adenylyl cyclase (AC) inhibitor SQ22536, phospholipase C (PLC) inhibitor U73122 and protein tyrosine kinase (TPK) inhibitor Genistein all deterred the increase of [Ca2+]i caused by E2-BSA. E2-BSA also increased the PLC protein and PKC protein significantly. Tamoxifen, an antagonist of estrogen receptor, did not inhibit the activation of PLC caused by E2-BSA. CONCLUSION: The E2-BSA has an effect on human spermatozoa in a nongenomic pathway, possibly through the transmembrane signal transduction in relation to AC, PLC and TPK.

[Feasibility and safety of right heart catheterization and pulmonary angiography through the antebrachium veins].

OBJECTIVE: To investigate the feasibility and safety of right heart catheterization through the antebrachium veins. METHODS: A total of 68 consecutive patients suspected with pulmonary vascular diseases underwent standard right heart catheterization and pulmonary angiography through the antebrachium veins were enrolled in this multicenter, cross-sectional study. RESULTS: The rate of successfully inserting the sheath into antebrachium veins was as high as 97.1% (66/68) and the rate of successfully performing right heart catheterization or pulmonary angiography through vascular access of antebrachium veins was 91.2% (62/68). The reasons of unsuccessful inserting the catheter to the right heart were due to the abnormality of antebrachium veins (2 cases) or stenosis of subclavian vein (3 cases) or unsatisfactory engorging of antebrachium veins since the history of drug injection (1 case). Haemorrhage of branch of axillary vein was the only adverse event occurred in one patient. CONCLUSION: It is a safe, convenient and well-tolerant option to perform right heart catheterization and pulmonary angiography through the vascular access of antebrachium veins.

Progesterone-Induced miR-145/miR-143 Inhibits the Proliferation of Endometrial Epithelial Cells.

Our previous study showed that progesterone (P4) can specifically regulate the expression of some microRNAs (miRNAs) in endometrial epithelium. In the present study, we verified the P4-dependent expression of miR-145/miR-143 in endometrial epithelial cells, explored the regulative mechanism of the P4 receptor (PR), and investigated their effects on the proliferation of endometrial epithelial cells. Our results showed that P4 can induce the expression of miR-145/143 in endometrial epithelial cells by acting on the PR A subtype. P4-induced miR-145/143 can inhibit the expression of cyclin D2 by binding to cyclin D2 mRNA 3'UTR. It can also inhibit cell proliferation in mouse endometrial epithelium by arresting the cell cycle during the G1-S checkpoint. Furthermore, miR-145 and miR-143 can inhibit the proliferation of human endometrial cancer cells. In conclusion, P4-induced miR-145/miR-143 is an important regulator in the proliferation of endometrial epithelial cells, and it can also inhibit the proliferation of human endometrial cancer cells. Our study indicates miRNAs are important mechanism of P4 in inhibiting the proliferation of endometrial epithelial cells. And these miRNAs are potential candidates for the diagnosis of endometrial cancer and therapeutic targets.

[Nongenomic action and mechanism of 17ß-estradiol in cytosolic calcium concentration in delayed implantation mouse endometrial stromal cells].

To investigate the existence of nongenomic action of 17ß-estradiol (E(2)) in the delayed implantation mouse endometrial stromal cells, the changes in intracellular calcium concentration ([Ca(2+)](i)) and the upstream of calcium signal in vitro were detected. The experiment was composed of two parts. Firstly, the change in [Ca(2+)](i) in endometrial stromal cells induced by E(2) under different conditions was detected. The mice were divided into 6 groups as follows: 0.1% dimethylsulfoxide (DMSO) control group, 1×10(-8) mol/L bovine serum albumin (BSA) control group, 1×10(-8) mol/L E(2) group, 1×10(-8) mol/L E(2) conjugated with BSA (E(2)-BSA) group, 1×10(-8) mol/L E(2) + calcium-free medium group, 1×10(-8) mol/L E(2) + 5 mg/mL tamoxifen group, with 4 mice in each group. The endometrial tissue was obtained from delayed implantation mice at pregnant day 7, and digested by incubation of tissue minces in Hankos balanced salts (HBSS, pH 7.2), which contained glucose (1 g/L), and collagenase I (0.125%), for 1 h at 37 degrees C. The stromal cells were preloaded with 2.5 mmol/L Fluo-3/AM, a fluorescent probe of calcium, for 30 min. A confocal laser scanning microscope, which fixed the wave length of excitation and emission at 488 nm and 526 nm, respectively, was used to detect the change in [Ca(2+)](i). Secondly, the mechanism of E(2) effects in endometrial stromal cells was investigated. Immunofluorescent method was used to detect the change in phosphorylation of phospholipase C (PLC) before and after the stromal cells were treated with E(2) for 5 min, 15 min, and 30 min. Seven delayed implantation mice were used. The results were as follows. [Ca(2+)](i) increased immediately and reached the maximum at 15 min after the stromal cells were treated with 1×10(-8) mol/L E(2) and returned to the normal level at 30 min. In E(2)-BSA group and E(2) + calcium-free medium group the same results were obtained as that in E(2) group, but there was no increase of [Ca(2+)](i) in DMSO and BSA groups. Tamoxifen, a traditional antagonist of estrogen receptor, did not inhibit the increase in [Ca(2+)](i) induced by E(2). Immunofluorescent results showed that the change in phosphorylated-PLC level had the same trend as [Ca(2+)](i) after the cells were treated with E(2). Compared with that in the control group, the immunofluorescent intensity increased at the beginning and achieved the maximum at 15 min (P<0.001), then declined to the normal level at 30 min. These results suggest that the rapid response of [Ca(2+)](i) induced by E(2) in the endometrial stromal cells in delayed implantation mice is possibly carried out through a nongenomic pathway, and the transmembrane signal transduction is related to the phosphorylation of PLC in this process.

[The progesterone-induced expression of cyclin G1 and its effect on the proliferation of mouse uterine epithelial cells].

The aim of the present study is to investigate the effect of progesterone-induced expression of cyclin G1 on the proliferation of endometrial epithelial cells. To obtain mouse endometrial epithelial cells, the uteri were isolated from ovariectomized mice which were injected subcutaneously with 100 ng estradiol per day for two days. Then the uteri were digested by dispase and pancreatin respectively. Endometrial epithelial cells were cultured in DMEM/F12 containing 6% fetal bovine serum, and divided into four groups when they grew to confluence. Each of the groups was treated as follows: Group E was treated with 0.01 micromol/L estradiol only, group P was treated with 1 micromol/L progesterone, group EP was treated with both 0.01 micromol/L estradiol and 1 micromol/L progesterone, and group C was treated with 0.01% DMSO for control. Immunocytochemistry was used to examine the expression of cyclin G1 protein. MTT assay was used to evaluate metabolic activity of cells. Flow cytometry was used to check the number of cells distributing in each phase of the cell cycle. The result of immunocytochemistry showed that there was no expression of cyclin G1 protein in group C and group E, while cyclin G1 was obviously expressed in group P and group EP and localized in nucleus. In the MTT assay, compared with group C, the viability of group E significantly increased, while that of both group P and group EP decreased significantly. The results of flow cytometry were in accordance with those of MTT, which showed that compared with group C, group E had a higher proportion of cells in S phase, while group P, as well as group EP had a lower proportion of cells in S phase but a higher proportion in G1 phase and G2/M phase. These results indicate that progesterone could induce cyclin G1 expression in the primary culture of mouse endometrial epithelial cells, meanwhile inhibit the proliferation of cells and block the cell cycle progression. Thus, progesterone-induced expression of cyclin G1 is probably a negative factor in regulating cell cycle, which is involved in the inhibitory effect of progesterone on the proliferation of endometrial epithelial cells.

[Temporospatial expression of cyclin G1 in normal human endometria].

OBJECTIVE: To study the temporospatial expression of cyclin G1 protein and mRNA in normal human endometrium and its physiological implications. METHODS: Human endometria samples were taken from 15 women in proliferative phase, 11 in early secretory phase, and 15 in mid-late secretary phase. Cyclin G1 protein and mRNA in the normal human endometria were measured by immunohistochemistry and in situ hybridization, respectively. RESULTS: The expression of cyclin G1 protein in the epithelium cells was low in proliferative phase. The expression increased at early secretary phase and reached the highest at mid-late secretary phase. The expression of cyclin G1 protein in stromal cells only appeared at mid-late secretary phase. The cyclin G1 protein was localized in nucleus. The expression of cyclin G1 mRNA was localized in cytoplasma, but had similar cycles as the expression of cyclin G1 protein. CONCLUSION: The expression of Cyclin G1 in normal human endometria is progesterone dependence.