Relationship Between the Serotypes and Hemagglutinin Gene Sequences of Avibacterium paragallinarum

Avibacterium paragallinarum has been subtyped into three serogroups (A, B, and C) and nine serovars (A-1, A-2, A-3, A-4, B-1, C-1, C-2, C-3, and C-4) according to the Page and Kume schemes. Both schemes use the hemagglutination inhibition test for serotyping. However, the relationship between the hemagglutinin gene (HMTp210) sequences and serotypes of A. paragallinarum is still unclear. This problem is partly due to the lack of information on the complete HMTp210 sequence from the formal reference strain of Page serogroup B (strain 0222 or Spross). In this study, we determined the complete HMTp210 sequence of strain Spross. The sequence of Spross and those of other HMTp210 sequences retrieved from GenBank were used to conduct phylogenetic analyses to investigate the relationship between the serotypes and HMTp210 sequences of A. paragallinarum. Four phylogenetic clusters, designated clusters A-1, A-2, B, and C, were identified. Clustering based on complete HMTp210 sequences correlates with serotyping based on hemagglutination inhibition tests. Serovar A-2 was found to contain a chimeric HMTp210 gene that might have resulted from recombination between serovar A-1 and serovar C-1. In addition, phylogenetic analysis based on partial sequences (approximately nucleotides 1-1200) of HMTp210 was sufficient to discriminate between serogroups A, B, and C. These findings could be valuable for developing a molecular method for serotyping of A. paragallinarum.

Molecular cloning and expression pattern of oriental river prawn (Macrobrachium nipponense) nitric oxide synthase

Nitric oxide synthase (NOS) produces nitric oxide (NO) by catalyzing the conversion of l-arginine to l-citrulline, with the concomitant oxidation of nicotinamide adenine dinucleotide phosphate. Recently, various studies have verified the importance of NOS invertebrates and invertebrates. However, the NOS gene family in the oriental river prawn Macrobrachium nipponense is poorly understood. In this study, we cloned the full-length NOS complementary DNA from M. nipponense (MnNOS) and characterized its expression pattern in different tissues and at different developmental stages. Real-time quantitative polymerase chain reaction (RT-qPCR) showed the MnNOS gene to be expressed in all investigated tissues, with the highest levels observed in the androgenic gland (P < 0.05). Our results revealed that the MnNOS gene may play a key role in M. nipponense male sexual differentiation. Moreover, RT-qPCR revealed that MnNOS mRNA expression was significantly increased in post-larvae 10 days after metamorphosis (P < 0.05). The expression of this gene in various tissues indicates that it may perform versatile biological functions in M. nipponense.

Identification of androgenic gland microRNA and their target genes to discover sex-related microRNA in the oriental river prawn, Macrobrachium nipponense

The oriental river prawn, Macrobrachium nipponense, is an important aquaculture species in China. The androgenic gland produces hormones that play crucial roles in the differentiation of crustaceans to the male sex. MicroRNA (miRNA) post-transcriptionally regulates many protein-coding genes, influencing important biological and metabolic processes. However, currently, there is no published data identifying miRNA in M. nipponense. In this study, we identified novel miRNA in the androgenic gland of M. nipponense. Using the high-throughput Illumina Solexa system, 1077 miRNA were identified from small RNA libraries by aligning with the de novo androgenic gland transcriptome of M. nipponense (obtained from RNA-Seq) and the sequences in the miRBase21 database. A total of 8,248, 76,011, and 78,307 target genes were predicted in the EST and SRA sequences provided in the NCBI database, and the androgenic gland transcriptome of M. nipponense, respectively. Some potential sex-related miRNA were identified based on the function of the predicted target genes. The results of our study provide new information regarding the miRNA expression in M. nipponense, which could be the basis for further genetic studies on decapod crustaceans.

Relaxin inhibits cardiac fibrosis and endothelial-mesenchymal transition via the Notch pathway

BACKGROUND

Relaxin (RLX) can prevent cardiac fibrosis. We aimed to investigate the possible mechanism and signal transduction pathway of RLX inhibiting cardiac fibrosis.

METHODS

Isoproterenol (5 mg·kg(-1)·d(-1)) was used to establish the cardiac fibrosis model in rats, which were administered RLX. The cardiac function, related targets of cardiac fibrosis, and endothelial-mesenchymal transition (EndMT) were measured. Transforming growth factor β (TGF-β) was used to induce EndMT in human umbilical vein endothelial cells, which were pretreated with RLX, 200 ng·mL(-1), then with the inhibitor of Notch. Transwell cell migration was used to evaluate cell migration. CD31 and vimentin content was determined by immunofluorescence staining and Western blot analysis. Notch protein level was examined by Western blot analysis.

RESULTS

RLX improved cardiac function in rats with cardiac fibrosis; it reduced the content of collagen I and III, increased the microvascular density of the myocardium, and suppressed the EndMT in heart tissue. In vitro, RLX decreased the mobility of human umbilical vein endothelial cells induced by TGF-β, increased the expression of endothelial CD31, and decreased vimentin content. Compared to TGF-β and RLX co-culture alone, TGF-β + RLX + Notch inhibitor increased cell mobility and the EndMT, but decreased the levels of Notch-1, HES-1, and Jagged-1 proteins.

CONCLUSION

RLX may inhibit the cardiac fibrosis via EndMT by Notch-mediated signaling.

Molecular cloning, characterization, and expression analysis of a Broad-Complex homolog during development in the oriental river prawn Macrobrachium nipponense

Broad-Complex (BR-C) is an early ecdysone-responsive gene encoding a family of zinc-finger transcription factors. In this study, we isolated the full-length cDNA of a BR-C homolog from the testes of the oriental river prawn (Macrobrachium nipponense), according to established expressed sequence tag information, using the rapid amplification of cDNA ends technique. The homolog was designated as MnBR-C. The full-length cDNA of MnBR-C contained a 1095-bp open reading frame encoding a precursor protein of 365 amino acid residues. Comparative and bioinformatic analyses revealed that MnBR-C exhibited a high degree of homology with BR-C proteins, and contained the BTB and Zf-H2C2-2 domains. Real-time quantitative polymerase chain reaction (qPCR) analysis revealed that the MnBR-C expression level varied significantly in the developing embryo, postembryonic larva, and adult tissue. Real-time qPCR showed that the MnBR-C gene was expressed in all of the tissues investigated, with the highest level of expression in the brain. In addition, MnBR-C was more abundantly expressed in the testes than in the ovaries.

Gene expression profile analysis of testis and ovary of oriental river prawn, Macrobrachium nipponense, reveals candidate reproduction-related genes

This study utilized high-throughput RNA sequencing technology to identify reproduction- and development-related genes of Macrobrachium nipponense by analyzing gene expression profiles of testis and ovary. More than 20 million 1 x 51-bp reads were obtained by Illumina sequencing, generating more than 7.7 and 11.7 million clean reads in the testis and ovary library, respectively. As a result, 10,018 unitags were supposed to be differentially expressed genes (DEGs) between ovary and testis. Compared to the ovary library, 4563 (45.5%) of these DEGs exhibited at least 6-fold upregulated expression, while 5455 (54.5%) DEGs exhibited at least 2-fold downregulated expression in the testis. The Gene Ontology (GO) enrichment analysis showed that 113 GO terms had potential molecular functions in reproduction. The Kyoto Encyclopedia of Genes and Genomes results revealed that the most important pathways may be relevant to reproduction and included 7 pathways. Forty-two genes were identified as reproduction-, development-, and sex-related genes based on GO classification and sequence comparison with other publications, including male reproductive-related LIM protein, spermatogenesis-associated protein, gametocyte-specific factor 1, VASA-like protein, vitellogenin, sex-determining protein fem-1, and other potential candidates. These results will advance research in the field of molecular genetics in M. nipponense and offer a valuable resource for further research related to reproduction in crustaceans.

Molecular cloning and expression analysis of two sex-lethal homolog genes during development in the oriental river prawn, Macrobrachium nipponense

In this study, two Sxl gene homologs, designated as Mnsxl1 and Mnsxl2, were cloned and characterized from the freshwater prawn Macrobrachium nipponense by rapid amplification of cDNA ends. The deduced amino acid sequences of Mnsxl1 and Mnsxl2 showed high sequence homology to the insect Sxl and contained conserved domains in two RNA-binding motifs. Real-time quantitative reverse transcription-polymerase chain reaction (RT-QPCR) showed that the Mnsxl1 and Mnsxl2 genes were expressed in all investigated tissues, with the highest level of expression in the intestine and liver. RT-QPCR also revealed that Mnsxl1 and Mnsxl2 mRNAs expressions were both significantly increased at 5 and 20 days post-larvae after metamorphosis. Thus, the results of the present study imply that Mnsxl1 and Mnsxl2 play complex and important roles in the sex differentiation of M. nipponense.

Absence of the adenosine A2A receptor confers pulmonary arterial hypertension and increased pulmonary vascular remodeling in mice

BACKGROUND

Pulmonary arterial hypertension (PAH) is characterized by sustained elevation of pulmonary vascular resistance resulting from endothelial and smooth muscle cell dysfunction and collagen deposition in pulmonary vascular walls. In this study, we investigated the role of the adenosine A(2A) receptor (A(2A)R) in the development of PAH by determining the effect of genetic inactivation of A(2A)Rs on pulmonary vascular remodeling in mice.

METHODS AND RESULTS

We characterized hemodynamic, histological and ultrastructural changes in pulmonary vascular remodeling in A(2A)R knockout (KO) mice compared with their wild-type (WT) littermates after exposure to normoxia and hypoxic conditions. After exposure to normoxia, compared to WT mice, A(2A)R KO mice displayed: (1) increased right ventricular systolic pressures and an elevated ratio of the right ventricle over left ventricle plus septum (Fulton index), (2) increased wall area and thickness as well as enhanced smooth muscle actin immunoreactivity in pulmonary resistance vessels, (3) increased proliferating cell nuclear antigen-positive cells in pulmonary resistance vessels and (4) increased smooth muscle cells hypertrophy and collagen deposition in the adventitia of pulmonary arteriole walls as revealed by electron microscope. By contrast, histological analysis revealed no features of hypertensive nephropathy in A(2A)R KO mice and there was no significant difference in systemic blood pressure, and left ventricular masses among the 3 genotypes. Furthermore, following chronic exposure to hypoxia, A(2A)R KO mice exhibited exacerbated elevation in right ventricular systolic pressure, hypertrophy of pulmonary resistance vessels and increased cell proliferation in pulmonary resistance vessels, compared to WT littermates. Thus, genetic inactivation of A(2A)Rs selectively produced PAH and associated increased smooth muscle proliferation and collagen deposition.

CONCLUSIONS

Extracellular adenosine acting at A(2A)Rs represents an important regulatory mechanism to control the development of PAH and pulmonary vascular remodeling.

Transport stress in broilers. II. Superoxide production, adenosine phosphate concentrations, and mRNA levels of avian uncoupling protein, avian adenine nucleotide translocator, and avian peroxisome proliferator-activated receptor-gamma coactivator-1alpha in skeletal muscles

The effect of transport stress on superoxide production and adenosine phosphate concentration in addition to avian uncoupling protein (avUCP), avian adenine nucleotide translocator, and avian peroxisome proliferator-activated receptor-gamma coactivator-1alpha mRNA levels of skeletal muscles in broilers was investigated. Arbor Acres chicks (n = 360, 46 d old, males) were randomly allotted to 1 of 5 treatments: unstressed control, 45-min (short-term) transport with 45-min (short-term) recovery, 45-min transport with 3-h (long-term) recovery, 3-h (long-term) transport with 45-min recovery, and 3-h transport with 3-h recovery. Each treatment consisted of 6 replicates with 12 birds each. All birds (except control group) were transported according to a designed protocol. Transport time affected reactive oxygen species production in the thigh muscle (P < 0.05), adenosine triphosphate (ATP) content and energy charge (EC) in both breast and thigh muscles (P < 0.05 for all 4 comparisons), ATP:adenosine diphosphate (ADP) ratio in the breast muscle (P < 0.05), and avUCP mRNA levels in the thigh muscle (P < 0.05). Long-term transport increased (P < 0.05) reactive oxygen species production, ATP content, ATP:ADP ratio, and EC in the thigh muscle, but it decreased ATP content, ATP:ADP ratio, and EC in the breast muscle. Long-term transport increased avUCP mRNA in the thigh muscle (P < 0.05). Long-term recovery increased the ATP (P < 0.05) and ADP (P < 0.05) concentrations, avian adenine nucleotide translocator mRNA (P < 0.05), and avian peroxisome proliferator-activated receptor-gamma coactivator-1alpha mRNA (P < 0.05) in the thigh muscle, whereas EC decreased (P < 0.05) in the breast muscle. There were interactions between transport and recovery time on ATP (P < 0.05), EC (P < 0.05), and avUCP mRNA level (P < 0.05) in the thigh muscle. This study suggests that long-term transport accelerates muscle energy metabolism and lipid peroxidation. A long-term recovery may help alleviate cellular damage and maintain meat quality by reducing the rate of energy metabolism and scavenging of free radicals formed.

Retroviral gene transfer of tissue-type plasminogen activator targets thrombolysis in vitro and in vivo

Patients usually have serious complications of thrombosis and bleeding by eating anticoagulation medicine for their residual lives after mechanical valve replacement operation. Tissue-type plasminogen activator (tPA) could target thrombolysis by activating plasminogen to fibrinolysin. In this study, we recombined a retroviral vector pLEGFP-N1-tPA and cultured purified packaging cells PT67/pLEGFP-N1-tPA to produce high-titer retrovirus. In vitro, two target cells, endothelial cell of umbilical vein (ECUV) 304 and heart muscle cell (HMC) that consist of endocardium and heart muscle, were infected by pLEGFP-N1-tPA. The results demonstrated that exogenous tPA was successfully transferred into ECUV304 and HMC. tPA in the two cells shows significant thrombolysis in plasma plate and the activity and content of tPA were high. Furthermore, in vivo, no thrombus was seen on the surface of Dacron patches (the same material making up a ring of mechanical valve) by tPA locally transferring around Dacron patches that were transplanted in the inferior caval veins of rabbits. tPA was successfully transferred into the local inferior caval vein. Activity and content of tPA were high in local tissue and blood and thrombolysis was effectively demonstrated by tPA rapidly, efficiently and long expressing. This laid the foundation for study and appliance of the tPA gene valve.

Antagonistic effects of melatonin on glutamate release and neurotoxicity in cerebral cortex

AIM

To observe the effects of melatonin (Mel) on glutamate (Glu) release from the cortical synaptosomes in old mice and on neurotoxicity induced by KCl, Glu in cultured cortical cells of fetal rat and to explore the antiaging mechanism of Mel.

METHODS

Glu release by the synaptosomes in old mouse cerebral cortex was detected in a spectrofluorophotometer. The neuronal viability in primary cultures from rat cerebral cortex was assessed using MTT stain and lactate dehydrogenase (LDH) efflux in the bathing medium.

RESULTS

Mel inhibited the K+ (30 mmol.L-1)-induced Glu release from synaptosomes either in calcium dependent or independent conditions [control (10.6 +/- 1.1), (9.2 +/- 0.7) mumol.g-1 (protein); Mel 0.1 mumol.L-1 (6.5 +/- 0.9), (7.5 +/- 0.6) mumol.g-1 (protein), respectively, P < 0.01 vs control group), increased MTT activity (control 0.67 +/- 0.04, 0.81 +/- 0.03; Mel 0.1 mumol.L-1 0.715 +/- 0.023, 0.925 +/- 0.027, P < 0.01 vs control group] and decreased LDH efflux (control 0.400 +/- 0.016, 0.379 +/- 0.016; Mel 0.1 mumol.L-1 0.345 +/- 0.021, 0.340 +/- 0.012, respectively, P < 0.01 vs control group), therefore, protected the neuronal viability against KCl and Glu-induced injury.

CONCLUSION

The inhibitory effect of Mel on Glu release from cortical synaptosome and the protective effect of Mel on cortical neurons against neurotoxicity are its antiaging mechanisms.

Effect of 17-beta-estradiol and ginsenoside Rg1 on reactive microglia induced by beta-amyloid peptides

The reactive microglias induced by 25 micromol of beta-amyloid peptides (Abeta25-35) and/or IFN-gamma can initiate the microglial respiratory burst and release NO, respectively. Oxidative stress and inflammatory function have been implicated in Alzheimer's disease (AD). We showed that 10 micromol 17-beta-estradiol (E2) and 1-10 micromol ginsenoside Rg1 (Rg1) could prevent the toxicity of Abeta25-35 and/or IFN-gamma to microglias, inhibit the microglial respiratory burst activity and decrease the accumulation of NO. These results demonstrated the protectional effect of E2 or Rg1 on neuron from damaging by reactive microglias in AD.

Interaction of berbamine compound E6 and calmodulin-dependent myosin light chain kinase

The interaction of the berbamine compound E6 and calmodulin (CaM)-dependent myosin light chain kinase (MLCK) has been studied. The experimental results showed that the inhibition of MLCK activity was increased with increasing amounts of E6 and was overcome completely by the addition of excessive CaM. The stimulatory activity of MLCK induced by CaM was gradually inhibited by the increasing concentrations of compound E6, showing that the inhibition of MLCK activity by compound E6 was concentration dependent; and the Ki was 0.95 microM. Compound E6 diminished the fluorescence intensity of dansyl-labeled CaM and the intensity was increased gradually by the addition of different amounts of CaM. Compound E6 had no effect on the activity of MLCK fragments produced by limited trypsinization, and it is a novel and considerably potent calmodulin antagonist.