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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.

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 αVβ3 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.

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.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.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.Our research has enriched the pathological mechanism of PCOS and may provide a new clue for the clinical treatment of PCOS.

We report a new pattern of a bicyclic helical peptide constructed through head-to-tail cross-linking. The described bicyclic helical peptide has a head-to-tail cross-linking arm and a C-terminal

Ovarian failure in postmenopausal female leads E2 to dramatic decrease which is an important reason of menopausal dyslipidemia. PCSK9 as a secretory lipid metabolic regulator plays a critical role in the cholesterol metabolism by negatively regulating LDLR in hepatocytes. Clinical data showed PCSK9 was elevated and positively correlated with LDL-C in the blood of postmenopausal women. However, the relationship between E2 and PCSK9 and the role of PCSK9 in postmenopausal dyslipidemia are still unclear. In this research, 10-week-old ovariectomized mice were fed for 4 weeks with normal diet or high-fat diet, then tested the lipid metabolism profiles and PCSK9 in the blood and the expression of LDLR and PCSK9 in the liver. On this basis, PCSK9-/- ovariectomized mice were used to further verify the effect of PCSK9 in dyslipidemia of ovariectomized mice. Finally, the ovariectomized mice with high-fat diet were subcutaneous injected respectively with E2 or PCSK9 inhibitor alone or both together for 2 weeks and were tested as previous experiment. The results showed PCSK9, TC and LDL-c all increased in the blood of in WT ovariectomized mice and their PCSK9 is positively correlated with LDL-c, while there were on obvious lipid metabolism disorder in the PCSK9−/− ovariectomized mice. PCSK9 inhibitor increased the LDLR on the liver and ameliorated the dyslipidemia in WT ovariectomized mice. It suggests that PCSK9 plays an important role in the dyslipidemia of ovariectomized mice, which provides a new strategy for clinical diagnosis and treatment of the dyslipidemia in post-menopause.

Uterine receptivity to the embryo is crucial for successful implantation. The establishment of uterine receptivity requires a large amount of energy, and abnormal energy regulation causes implantation failure. Glucose metabolism in the endometrium is tissue specific. Glucose is largely stored in the form of glycogen, which is the main energy source for the endometrium. AMP-activated protein kinase (AMPK), an important energy-sensing molecule, is a key player in the regulation of glucose metabolism and its regulation is also tissue specific. However, the mechanism of energy regulation in the endometrium for the establishment of uterine receptivity remains to be elucidated. In this study, we aimed to investigate the energy regulation mechanism of mouse uterine receptivity and its significance in embryo implantation. The results showed that the AMPK, p-AMPK, glycogen synthase 1, and glycogen phosphorylase M levels and the glycogen content in mouse endometrial epithelium varied in a periodic manner under regulation by the ovarian hormone. Specifically, progesterone significantly activated AMPK, promoted glycogenolysis, and upregulated glycogen phosphorylase M expression. AMPK regulated glycogen phosphorylase M expression and promoted glycogenolysis. AMPK was also found to be activated by changes in the energy or glycogen of the endometrial epithelial cells. The inhibition of AMPK activity or glycogenolysis altered the uterine receptivity markers during the window of implantation and ultimately interfered with implantation. In summary, consistency and synchronization of AMPK and glycogen metabolism constitute the core regulatory mechanism in mouse endometrial epithelial cells involved in the establishment of uterine receptivity.

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.

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 αVβ3 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.

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.

Background To evaluate the clinical characteristic, microsurgical treatment and outcomes of patients with multi-segment intramedullary cervical spinal cord tumors (MSICCT). Materials and methods Prospective single center cohort study. 63 patients underwent microsurgery for MSICCT. Pre and postoperative function were assessed using the modified McCormick's grade, IJOA scoring system, and analyzed using the appropriate statistical tests. Results 41 males, 22 females, three spinal segments were involved in 22(35%) cases, four or more in 41(65%) of cases. Majority of the tumors were ependymoma (54%), followed by astrocytoma (low grade 25%, high grade 8%). McCormick's grade: I&II in 40 patients (64%). There was no statistical difference between preoperative and three-month postoperative IJOA scores (P = 0.76), indicating no significant neurological deterioration after surgery. The extent of surgical resection was highly correlated to histological tumor type of MSICCT (χ2 = 34.82, P = 0.0001) and three-month postoperative IJOA scores (F = 2.62, P = 0.006). There is a high proportion of total resection in ependymomas, haemangioblastomas, cavernomas and schwannoma, whereas, we only achieved partial resection in most gliomas. With a mean follow up of 5.5 years (3 months–more than 12 years), clinical outcome improved or stabilized in 91% of cases (80% improved, 11% stabilized, 9% deteriorated). Conclusion This series of MSICCT showed that high extent of surgical resection could be achieved in most ependymomas with good long-term outcome. Astrocytomas, in contrary remained challenging with 25% achieved gross total resection. Overall, compared to previous surgical series, we showed encouraging improvement in the clinical outcome of these patients managed surgically.

The mixture of several effluents, caused by the improper handling and management of effluents, generated multi-component wastewater containing both metals and dyes, leading to the complicated treatment process. In this study, a continuous adsorption of Pb(II) and methylene blue (MB) has been studied in single and binary solutions by using graphite oxide coated sand (GO-sand) as an adsorbent in a fixed-bed column. GO-sand was analyzed by X-ray photoelectron spectroscopy before and after analyte adsorption. Compared with sand filter, adsorption quantity and capacity for Pb(II) and MB by GO-sand filter were greatly increased. In Pb(II) and MB single solutions, the experimental parameters were investigated in detail including initial concentration, flow rate, bed depth and pH. Exhaustion time decreased with increasing initial concentration and flow rate, and increased with increasing bed depth and pH. In the Pb(II)-MB binary solution, exhaustion time significantly decreased for Pb(II) adsorption, but increased for MB adsorption. The reason was explained that the more favorable adsorption for MB onto the surface of GO-sand than that for Pb(II), which was derived from π–π interaction between MB and GO on sand surface in packed filter. The Yoon–Nelson model was applied at different concentration of Pb(II) and MB to predict the breakthrough curves. The experimental data were well fit with the model indicating that it was suitable for this column design.