Propofol induces apoptosis and inhibits the proliferation of rat embryonic neural stem cells via gamma-aminobutyric acid type A receptor.

We investigated the effect of propofol on the proliferation and viability of rat embryonic neural stem cells (rENSCs) and the potential mechanisms involved. rENSCs were isolated and cultured in vitro and treated with 1, 10, or 50 µM propofol, while the control group was treated with 0.1 µM dimethyl sulfoxide. The effect of propofol on the proliferation and viability of rENSCs was examined by proliferation and apoptosis assays. Real-time polymerase chain reaction was employed to analyze the mRNA expression of checkpoint kinase 1 (Chk1) and p53 in rENSCs exposed to propofol. Immunoprecipitation assay and western blotting analysis were performed to analyze the effect of propofol on Chk1 and p53 activity. The gamma-aminobutyric acid type A (GABAA) receptor antagonist securinine was added to the rENSCs before being treated with propofol to investigate the role of the GABAA receptor in propofol-triggered effects on rENSCs. rENSCs specifically expressing nestin protein were successfully isolated and cultured for experiments. The inhibitory effect of propofol on rENSCs increased dose-dependently. The percentage of apoptotic cells increased to 11.7% and the activity of Chk1 and p53 enhanced after treatment with 50 µM propofol. However, addition of securinine abrogated propofol-induced apoptosis and activation of Chk1. The GABAA receptor mediates propofol-induced apoptosis and proliferation inhibition of rENSCs, possibly by modulating the Chk1/p53 signaling pathway.

Molecular cloning and characterization of a proliferating cell nuclear antigen gene by chemically induced male sterility in wheat (Triticum aestivum L.).

Although a number of studies have shown that chemical hybridizing agents (CHAs) affect anther growth and regulate cell-cycle progression, little is known about the molecular and cellular mechanisms involved. Proliferating cell nuclear antigen (PCNA) is an essential factor in DNA replication, and in many other processes in eukaryotic cells. In this study, the open reading frame of TaPCNA, the PCNA in wheat (Triticum aestivum L.), was cloned by reverse transcription polymerase chain reaction (RT-PCR). Sequence analysis revealed that this gene was 792-bp long and encoded a protein with 234 amino acids. Alignment of the TaPCNA-predicted sequence revealed a high degree of identity with PCNAs from other plant species. A subcellular localization assay indicated that TaPCNA was localized in the nucleus. The TaPCNA was cloned into the prokaryotic expression plasmid pET32a, and the recombinant plasmid was transformed into BL21 (DE3). TaPCNA expression was induced by 0.5 mM isopropyl-beta-D-thiogalactopyranoside and verified using sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blot assays, which indicated that the fusion protein was successfully expressed. The gene involved in the G1-to-S transition, Histone H4, was downregulated by 1376- CIMS, which is a chemically induced male sterility line. However, a semi-quantitative RT-PCR revealed that TaPCNA expression was upregulated in 1376-CIMS. Our results suggest that CHAs (SQ-1) induce DNA damage in wheat anthers. DNA damage results in either the delay or arrest of cell-cycle progression, which affects anther development. This study will help to elucidate the mechanisms of SQ-1-induced male sterility.

Role of IL-6 polymorphism on the development of cardiovascular events and coronary artery disease in patients receiving hemodialysis.

We aimed to investigate the role of IL-6 polymorphism on the development of cardiovascular events and coronary artery disease in patients receiving hemodialysis. Blood samples were collected from 216 patients receiving hemodialysis treatment. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to genotype IL-6 -634C/G, -174G/C and -572C/G. By multivariate analysis, we found that the IL-6 -634GG genotype was associated with increased risk of cardiovascular events in patients receiving hemodialysis, with HR (95%CI) of 4.07 (1.20-15.70). Similarly, we found that the IL-6-174CC genotype was related to the onset and development of cardiovascular events in patients receiving hemodialysis, with HR (95%CI) of 3.33 (1.21-9.51). However, we did not find an association between IL-6 -572C/G polymorphism and risk of cardiovascular events in patients receiving hemodialysis.

Relationship between male sterility and ß-1,3-glucanase activity and callose deposition-related gene expression in wheat (Triticum aestivum L.).

In previous studies, we first isolated one different protein ß-1,3-glucanase using two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry from normal wheat (Triticum aestivum L.) and chemical hybridization agent-induced male sterility (CIMS) wheat. In this experiment, ß-1,3-glucanase activity and the expression of a callose deposition-related gene, UDP-glucose phosphorylase (UGPase), were determinate in normal, CIMS, and genetic male sterility (GS) wheat. ß-1,3-glucanase activity was significantly different between the fertile and sterile lines during callose synthesis and degradation, but there was no difference between CIMS and GS wheat. The UGPase gene of callose deposition was highly expressed in the meiophase and sharply decreased in the tetrad stage. However, the expression of the UGPase gene was significantly different between the fertile and sterile lines. These data indicated that ß-1,3-glucanase activity and the expression of the UGPase gene play important roles in the male sterility of wheat. Consequently, pollen mother cells (PMCs) might degenerate at the early meiosis stage, and differences in UGPase gene expression and ß-1,3-glucanase activity might eventually result in complete pollen collapse. In addition, the critical period of anther abortion might be the meiosis stage to the tetrad stage rather than what we previously thought, the mononuclear period.

Meta-analysis of association between IL-6 -634C/G polymorphism and osteoporosis.

Osteoporosis is a common disease in the aging population and studies have shown that interleukin-6 (IL-6) is potentially implicated in its pathogenesis. This study was designed to assess the association between the IL-6 gene -634C/G polymorphism and osteoporosis. PubMed, Embase, China National Knowledge Infrastructure, and Wanfang databases were searched for eligible studies published up to and including December 2014 in English or Chinese. Meta-analysis was conducted by the RevMan5.2 software. Weighted mean difference and 95% confidence interval (95%CI) were calculated by a fixed-effect or random-effect model. Bone mineral density (BMD) was regarded as the assessment index. As a result, a total of four articles with 3068 subjects were included. Differences in BMD between the CC and GG genotypes were 0.03 g/cm(2) (95%CI = 0.01 to 0.05) at total body, 0.01 g/cm(2) (95%CI = 0.00 to 0.03) at femoral neck, and 0.03 g/cm(2) (95%CI = 0.00 to 0.06) at the lumbar spine (P < 0.05). For the CG versus GG genotypes, the differences in BMD were 0.03 g/cm(2) (95%CI = 0.02 to 0.05) at total body and 0.02 g/cm(2) (95%CI = 0.00 to 0.03 at the femoral neck (P < 0.05). For the CC versus CG genotypes, the differences in BMD were not significant (P > 0.05). In conclusion, the GG genotype of the -634C/G polymorphism in IL-6 appears to play a role in reducing BMD, which affects normal bone metabolism and leads to osteoporosis.

A Medicago truncatula H+-pyrophosphatase gene, MtVP1, improves sucrose accumulation and anthocyanin biosynthesis in potato (Solanum tuberosum L.).

We recently cloned MtVP1, a type I vacuolar-type H(+)-translocating inorganic pyrophosphatase from Medicago truncatula. In the present study, we investigated the cellular location and the function of this H(+)-PPase in Arabidopsis and potato (Solanum tuberosum L.). An MtVP1::enhanced green fluorescent protein fusion was constructed, which localized to the plasma membrane of onion epidermal cells. Transgenic Arabidopsis thaliana overexpressing MtVP1 had more robust root systems and redder shoots than wild-type (WT) plants under conditions of cold stress. Furthermore, overexpression of MtVP1 in potato accelerated the formation and growth of vegetative organs. The tuber buds and stem base of transgenic potatoes became redder than those of WT plants, but flowering was delayed by approximately half a month. Interestingly, anthocyanin biosynthesis was promoted in transgenic Arabidopsis seedlings and potato tuber buds. The sucrose concentration of transgenic potato tubers and tuber buds was enhanced compared with that of WT plants. Furthermore, sucrose concentration in tubers was higher than that in tuber buds. Although there was no direct evidence to support Fuglsang's hypothetical model regarding the effects of H(+)-PPase on sucrose phloem loading, we speculated that sucrose concentration was increased in tuber buds owing to the increased concentration in tubers. Therefore, overexpressed MtVP1 enhanced sucrose accumulation of source organs, which might enhance sucrose transport to sink organs, thus affecting anthocyanin biosynthesis.

Expression profile of insulin-like growth factor system genes in muscle tissues during the postnatal development growth stage in ducks.

Insulin-like growth factors (IGFs) are regulators that modulate the proliferation and differentiation of muscle tissues. We quantified the messenger RNA (mRNA) expression of IGF-I, IGF-II, and type I and II IGF receptors (IGF-IR and IGF-IIR) in muscle tissues including the breast, leg, and myocardium during an early postnatal development growth stage (post-hatching weeks 1-8) in ducks. The results showed a significant age-related change in mRNA in these muscle tissues. In breast muscle, the developmental expression of IGF-I and IGF-II was highest during week 1 but decreased quickly and maintained a relatively lower level. Leg muscle had the highest mRNA expression of IGF-I and IGF-II genes at week 3. In myocardial tissues, the expression level of IGF-IR and IGF-IIR genes exhibited a "rise-decline" developmental trend. The expression patterns of IGF-I/IGF-IR and IGF-II/IGF-IIR were different between weeks 4 and 6. The same expression pattern was observed for IGF-I and IGF-IR; however, it was different from that observed for IGF-II and IGF-IIR. Our results showed a negative correlation between IGF-II mRNA expression and leg muscle weight at week 4 (P < 0.05). A negative correlation was also found between IGF-II mRNA expression and breast muscle weight (P < 0.01), and a positive correlation was found between IGF-IR expression and breast muscle weight. At week 6, a positive correlation was found between IGF-IR expression and breast muscle weight. However, at week 8, a negative correlation was found between IGF-IR expression and breast muscle weight. The results showed that the expression of IGF mRNA in duck tissues exhibits a specific developmental trend and an age-related pattern, suggesting that the regulation mechanism of these 4 genes in proliferation and differentiation of muscle tissues differed.