91 research outputs found
Germination characteristics among different sheepgrass (Leymus chinensis) germplasm during the seed development and after-ripening stages
Sheepgrass (Leymus chinensis (Trin.) Tzvel) is an important forage grass in the Eurasian steppe. However, little information is available concerning its seed morphological features and germination characteristics during seed development and after-ripening among different germplasm. To clarify the appropriate seed harvest time and the effects of germplasm, seed development and after-ripening on seed germination, 20 germplasm of sheepgrass were selected. Moreover, the seed morphological and physical changes as well as the seed germination and dormancy characteristics of sheepgrass during seed development stages were analyzed using a seven—d gradient of day after pollination (DAP). The results indicated that the seed water content decreased significantly during 35–42 DAP and that the highest seed germination rate of most germplasm was observed at 35–42 DAP. Thus, 35–42 DAP may be the best time to harvest sheepgrass to obtain the maximum seed germination rate and avoid seed shattering. Furthermore, our results indicated that there were six types of germination patterns, including germplasm with increasing germination rates in the developing seed, such as S19 and S13, and germplasm that maintained a consistently low germination rate, such as S10. Moreover, we compared the seed germination rate of eight germplasm during seed development in both 2016 and 2017, and the results indicated that the seed germination patterns of the eight germplasm were highly consistent between the two consecutive years, suggesting that germplasm rather than year is the major factor in determining germination during seed development. The effect of after-ripening on seed germination was different among the germplasm where four types of germination patterns were revealed for 10 germplasm and resulted in various dormancy features. A two-factor ANOVA analysis suggested that the germplasm of the sheepgrass has a large influence on seed germination, whether during seed development or after-ripening. Thus, these findings lay the foundation for future studies on seed dormancy and germination and may guide the breeding of new cultivars of sheepgrass with better germination performance
Fibroblast growth factor-1 (FGF-1) promotes adipogenesis by downregulation of carboxypeptidase A4 (CPA4) – a negative regulator of adipogenesis implicated in the modulation of local and systemic insulin sensitivity
Fibroblast growth factor-1 (FGF-1) promotes differentiation of human preadipocytes into mature adipocytes via modulation of a BMP and Activin Membrane-Bound Inhibitor (BAMBI)/Peroxisome proliferator-activated receptor (PPAR?)-dependent network. Here, we combined transcriptomic and functional investigations to identify novel downstream effectors aligned with complementary analyses of gene expression in human adipose tissue to explore relationships with insulin sensitivity. RNA-Seq and qRT-PCR analysis revealed significant down-regulation of carboxypeptidase A4 (CPA4) following FGF-1 treatment or induction of differentiation of human preadipocytes in a BAMBI/PPAR?-independent manner. siRNA-mediated knockdown of CPA4 resulted in enhanced differentiation of human preadipocytes. Furthermore, expression of CPA4 in subcutaneous adipose tissue correlated negatively with indices of local and systemic (liver and muscle) insulin sensitivity. These results identify CPA4 as a negative regulator of adipogenesis that is down-regulated by FGF-1 and a putative deleterious modulator of local and systemic insulin sensitivity. Further investigations are required to define the molecular mechanism(s) involved and potential therapeutic opportunities
Regulation of Adipogenesis by Quinine through the ERK/S6 Pathway
Quinine is a bitter tasting compound that is involved in the regulation of body weight as demonstrated in in vivo animal models and in vitro models of the adipogenic system. Arguments exist over the positive or negative roles of quinine in both in vivo animal models and in vitro cell models, which motivates us to further investigate the functions of quinine in the in vitro adipogenic system. To clarify the regulatory functions of quinine in adipogenesis, mouse primary preadipocytes were induced for differentiation with quinine supplementation. The results showed that quinine enhanced adipogenesis in a dose dependent manner without affecting lipolysis. The pro-adipogenic effect of quinine was specific, as other bitter tasting agonists had no effect on adipogenesis. Moreover, the pro-adipogenic effect of quinine was mediated by activation of ERK/S6 (extracellular-signal-regulated kinase/Ribosomal protein S6) signaling. Knockdown of bitter taste receptor T2R106 (taste receptor, type 2, member 106) impaired the pro-adipogenic effect of quinine and suppressed the activation of ERK/S6 signaling. Taken together, quinine stimulates adipogenesis through ERK/S6 signaling, which at least partly functions via T2R106
Mouse Maternal High-Fat Intake Dynamically Programmed mRNA m6A Modifications in Adipose and Skeletal Muscle Tissues in Offspring
Epigenetic mechanisms have an important role in the pre- and peri-conceptional programming by maternal nutrition. Yet, whether or not RNA m6A methylation—an old epigenetic marker receiving increased attention recently—is involved remains an unknown question. In this study, mouse high-fat feeding prior to conception was shown to induce overweight and glucose intolerant dams, which then continued to be exposed to a high-fat diet during gestation and lactation. The dams on a standard diet throughout the whole experiment were used as a control. Results showed that maternal high-fat intake impaired postnatal growth in male offspring, indicated by decreased body weight and Lee’s index at 3, 8 and 15 weeks old, but the percentages of visceral fat and tibialis anterior relative to the whole body weights were significantly increased at eight weeks of age. The maternal high-fat exposure significantly increased mRNA N6-methyladenosine (m6A) levels in visceral fat at three weeks old, combined with downregulated Fat mass and obesity-associated gene (FTO) and upregulated Methyltransferase like 3 (METTL3) transcription, and these changes were reversed at eight weeks of age. In the tibialis anterior muscle, the maternal high-fat diet significantly enhanced m6A modifications at three weeks, and lowered m6A levels at 15 weeks of age. Accordingly, FTO transcription was significantly inhibited at three weeks and stimulated at 15 weeks of age, and METTL3 transcripts were significantly improved at three weeks. Interestingly, both FTO and METTL3 transcription was significantly elevated at eight weeks of age, and yet the m6A modifications remained unchanged. Our study showed that maternal high-fat intake could affect mRNA m6A modifications and its related genes in offspring in a tissue-specific and development-dependent way, and provided an interesting indication of the working of the m6A system during the transmission from maternal nutrition to subsequent generations
Rho-Associated Protein Kinases Play an Important Role in the Differentiation of Rat Adipose-Derived Stromal Cells into Cardiomyocytes In Vitro
<div><p>Adipose-derived stromal cells (ADSCs) represent a readily available abundant supply of mesenchymal stem cells and have the ability to differentiate into cardiomyocytes in mice and human, making ADSCs a promising source of cardiomyocytes for transplantation. However, there has been no report of differentiation of rat ADSCs into cardiomyocytes. In addition, signaling pathways in the differentiation process from ADSCs to cardiomyocytes are unknown. In this study, we first demonstrated that rat ADSCs spontaneously differentiated into cardiomyocytes in vitro, when cultured on a complete medium formulation MethoCult GF M3534. These differentiated cells possessed cardiomyocyte phenotype and expressed cardiac markers. Moreover, these cells showed open excitation-contracting coupling and Ca<sup>2+</sup> transient and contracted spontaneously. The role of Rho-associated protein kinases (ROCKs) in the differentiation process was then studied by using ROCK-specific inhibitor Y-27632 and ROCK siRNAs. These agents changed the arrangement of cytoskeleton and diminished appearance of cardiomyocyte phenotype, accompanied by inhibition of c-Jun N-terminal kinase (JNK) phosphorylation and promotion of Akt phosphorylation. Collectively, this is the first study to demonstrate that rat ADSCs could spontaneously differentiate into cardiomyocytes in vitro and ROCKs play an important role in the differentiation of ADSCs into beating cardiomyocytes in conjunction of the PI3K/Akt pathway and the JNK pathway.</p></div
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Astaxanthin improves preserved semen quality at 17 degrees C by enhancing sperm antioxidant and motility properties
Porcine sperm is rich in polyunsaturated fatty acids; therefore, it is highly susceptible to oxidative damage during storage. Inhibition of oxidative stress during preservation is essential for maintaining sperm motility. Astaxanthin is a potent antioxidant used in the cosmetic and pharmaceutical industries. This study aimed to explore the effect of supplementing astaxanthin as an extender of porcine semen preservation dilutions at 17 degrees C. Various concentrations of astaxanthin were added to diluted porcine semen at 17 degrees C. We performed computer-assisted semen analysis, evaluation of plasma membrane integrity and acrosome integrity, and measurement of total antioxidant activity, malondialdehyde (MDA) content, reactive oxygen species levels, superoxide dismutase (SOD) activity, catalase (CAT) activity, glutathione peroxidase (GSH-PX) activity and sperm motility parameters. Compared with the control group, the addition of 0.25 mu g/ml astaxanthin group significantly improved sperm motility parameters stored on the fifth day; these were increased levels of sperm SOD, GSH-PX and CAT (p < .05), increased sperm adenosine trisphosphate and lactate dehydrogenase levels and decreased sperm MDA levels (p < .05). These findings suggest that adding 0.25 mu g/ml of astaxanthin improves the quality of porcine semen stored at 17 degrees C. Our findings provide theoretical support for developing new protective agents critical for preserving pig semen at 17 degrees C
Mineralization characteristics and geological significance of Rb-rich granitic pegmatite veins in Shangnan-Danfeng area, eastern Qinling belt
Granitic pegmatite is an important source of rare metal minerals, but its mineralization characteristics need to be further studied. This study conducted a combined field geological, indoor microscopic and major-trace elemental investigation on the petrological and geochemical characteristics of the Ziyugou Rb-rich granitic pegmatite veins in the Shangnan-Danfeng area of the eastern Qinling belt. The Ziyugou granitic pegmatites intruded the Danfeng Group. After comprehensive evaluation, 14 Rb-rich granitic pegmatite veins have been identified. On the basis of garnet contents and alteration types, the granitic pegmatites can be divided into five types: microcline granitic pegmatite, garnet-rich microcline granitic pegmatite, greisenized microcline granitic pegmatite, greisenized garnet-rich microcline granitic pegmatite and silicified microcline granitic pegmatite. The Ziyugou granitic pegmatite veins are generally peraluminous, rich in Rb, HFSE and HREE but depleted in Ba, Sr and Ti. Granitic pegmatite veins with little or without alteration usually contain highest Rb contents. Therefore, primary microcline, garnet, secondary muscovite and quartz can be served as key minerals to effectively indicate the Rb fertility of granitic pegmatite veins. The Ziyugou granitic pegmatite veins obviously postdate the Kuanping granite, and both of them exhibit significantly different geochemical characteristics. These features strongly indicate that the Ziyugou granitic pegmatite veins cannot be derived from the magmas forming the Kuanping granite, and their parent rocks were speculated to be located in depth
Morphology and expression of cardiac markers before and after differentiation of ADSCs into cardiomyocytes.
<p>(A) Morphological change of ADSCs into cardiomyocytes in the absence (left panels) or presence (right panels) of ROCK-specific inhibitor Y-27632. After 6 days of culture, spindle shaped cells (black arrow), small round cells (gray arrow) and small tube cells (white arrow) appeared in the top panel, with no beating. After 12 days, single contractive cells (white arrow) were shown in the center panel; After 18dyas, myotube-like structure formed a cohesive network in the bottom panels and they began to contract synchronously. Scale bars  = 100 µm. (B) Expression of cardiac genes was determined by RT-PCR before (lane 1 for undifferentiated ADSCs) and after (lane 2 for beating cells) differentiation of ADSCs into cardiomyocytes. Rat heart tissue was used as a positive control (lane 4), with no cDNA as a negative control (lane 3). Expression of α-cardiac actin, α-MHC, β-MHC, ANP, cTnT, GATA4 and MEF-2C mRNA was higher in ADSCs-derived beating cells than in undifferentiated ADSCs.</p
Differential protein expression by undifferentiated ADSCs and ADSCs-derived cells in the absence or presence of Y-27632.
<p>Expression of cMHC (A), cTnI (B), Connexin 45 (C) and RyR2/DHPR (D) in the ADSCs (day 3) and ADSCs-derived cells (day 16, in the absence or presence of Y-27632) by flow cytometer analyses. Right column figures represent results from 3 independent experiments. * <i>P</i><0.05.</p
Expression of cardiac proteins, excitation-contraction coupling proteins and signaling proteins in beating cardiomyocytes.
<p>Expression of MLC-2v(A), cTnT(B) and RyR2/DHPR (C) in the SCR siRNA and ROCK siRNA groups by flow cytometer analyses. (D) Change of JNK and PI3K/Akt from Western Blot analyses. Lane 1 represents undifferentiated ADSCs (day 3), while lanes 2 to 5represent SCR siRNA, ROCKI siRNA, ROCKII siRNA and Both siRNA groups, respectively (day 16). Phosphorylation level  =  phosphorylation/total. * <i>P</i><0.05.</p
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