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Abstract Spermidine/spermine N1-acetyltransferase (SSAT) is a catabolic regulator of polyamines, ubiquitous molecules essential for cell proliferation and differentiation. In this study, the molecular characterization of the SSAT1 gene of the Sichuan white goose was analyzed, as well as its expression profiles in various follicles and tissues. The open reading frame of the SSAT1 cDNA (GenBank No. KM925008) is 516 bp in length and encodes a 171-amino acid protein with a putative molecular weight of 20 kDa. The predicted SSAT1 protein is highly conserved with those of other species, especially Gallus gallus. SSAT1 mRNA was ubiquitously expressed in all the examined tissues. The highest level of SSAT1 mRNA expression was found in the pineal gland (P<0.05), and was 12-fold greater than in the heart. The level of SSAT1 mRNA expression was relatively lower in preovulatory follicles, while it was higher in postovulatory follicles (POFs), particularly in POF1. Furthermore, as postovulatory follicles degenerated, SSAT1 expression gradually decreased. Our findings suggest that SSAT1 might play important roles in mediating the physiological function of the pineal gland and regulating the regression of POFs. [ABSTRACT FROM AUTHOR]

This paper systematically investigates the biomedical performance of selective laser melted (SLM) porous Ti6Al4V ELI scaffolds for bone implantation through in vitro and in vivo experiments. Scaffolds with pore sizes of 500 μm, 600 μm and 700 μm and porosities of 60% and 70% were manufactured in order to explore the optimum pore size and porosity. Rat bone marrow mesenchymal stem cells (rBMMSCs) were used in the in vitro experiments. Cell Counting Kit-8, live/dead staining and scanning electron microscope were used to assess the cytotoxicity of the porous scaffolds. DNA content quantification was performed to investigate cell proliferation on the porous scaffolds. The osteogenic differentiation of cells was measured by alkaline phosphatase (ALP) activity and osteogenic gene expressions, including bone morphogenetic protein-2 (BMP-2), collagen type 1α1 (COL-1), osteocalcin (OCN), osteopontin (OPN) and runt-related transcription factor-2 (RUNX-2). The Sprague-Dawley (SD) rat models with distal femoral condyles defect were used in the in vivo experiments. Micro-CT analysis and histological analysis were performed after implantation surgery to reveal the bone ingrowth into the porous scaffolds. All in vitro data were analyzed by one-way ANOVA followed by Tukey post hoc tests, in vivo data were analyzed using Kruskall-Wallis ANOVA and Conover-Inman post-hoc test. Based on the in vitro and in vivo experiments, it is found that the porous scaffolds manufactured by SLM did not induce a cytotoxic effect. Among all the porous scaffolds, the scaffold with a pore size of 500 μm and porosity of 60% showed the best cell proliferation and osteogenic differentiation (in vitro experiments) and bone ingrowth (in vivo experiments). • Systematically investigations of SLM Ti6Al4V ELI scaffolds for bone implantation through in vitro and in vivo experiments were conducted. • Based on the in vitro and in vivo experiments, it is found that the SLM scaffolds did not induce a cytotoxic effect. • The SLM scaffold with a pore size of 500μm and porosity of 60% showed the best cell proliferation and osteogenic differentiation and bone ingrowth. [ABSTRACT FROM AUTHOR]

Ornithine decarboxylase antizyme 1 (OAZ1) regulates both polyamine biosynthesis and transport and acts as a tumor suppressor because of its functions in the regulation of cell proliferation, apoptosis and growth. However, the roles of OAZ1 in the regulation of polyamine metabolism, cell proliferation, apoptosis and hormone receptor expression in granulosa cells (GCs) from geese have not been determined. To define the roles of OAZ1 in primary GCs, we constructed and transfected an Oaz1 overexpression vector with a thymidine deletion into primary GCs. Oaz1 overexpression induced 65 and 30% decreases in the putrescine and spermidine contents, respectively, 225% increase in the spermine content and up-regulated the expression levels of genes associated with polyamine metabolism (but Oaz2). The Ccnd1, Pcna, Bax and Caspase 3 mRNA expression levels in GCs overexpressing Oaz1 were significantly higher than the expression levels in the vehicle group ( p < 0.05). Additionally, a slight increase in the E2 concentration in the culture medium and enhanced Er, Fshr and Lhr expression were observed in the GCs 24 h after Oaz1 overexpression ( p < 0.05). These data suggested that Oaz1 up-regulated the expression of genes related to polyamine metabolic enzymes and reproductive hormone receptors, disturbed intracellular polyamine homeostasis, and affected the transcription of genes associated to cell proliferation and apoptosis in goose primary GCs. Taken together, our results indicate that modifying polyamine metabolism by Oaz1 may interfere with the expression of genes involved in cell proliferation, apoptosis and responsiveness of ovary toward hormones in goose GCs. [ABSTRACT FROM AUTHOR]

An increasing number of studies suggest that ornithine decarboxylase antizyme 1 (OAZ1), which is regarded as a tumor suppressor gene, regulates follicular development, ovulation, and steroidogenesis. The granulosa cells in the ovary play a critical role in these ovarian functions. However, the action of OAZ1 mediating physiological functions of granulosa cells is obscure. OAZ1 knockdown in granulosa cells of geese was carried out in the current study. The effect of OAZ1 knockdown on polyamine metabolism, cell proliferation, apoptosis, and hormone receptor transcription of primary granulosa cells in geese was measured. The viability of granulosa cells transfected with the shRNA OAZ1 at 48 h was significantly higher than the control (p<0.05). The level of putrescine and spermidine in granulosa cells down-regulating OAZ1 was 7.04- and 2.11- fold higher compared with the control, respectively (p<0.05). The CCND1, SMAD1, and BCL-2 mRNA expression levels in granulosa cells down-regulating OAZ1 were each significantly higher than the control, respectively (p<0.05), whereas the PCNA and CASPASE 3 expression levels were significantly lower than the control (p<0.05). The estradiol concentration, ER and LHR mRNA expression levels were significantly lower in granulosa cells down-regulating OAZ1 compared with the control (p<0.05). Taken together, our results indicated that OAZ1 knockdown elevated the putrescine and spermidine contents and enhanced granulosa cell viability and inhibited ER and LHR transcriptions of granulosa cells in geese. [ABSTRACT FROM AUTHOR]