The SOCS and STAT from JAK/STAT signaling pathway of kuruma shrimp Marsupenaeus japonicus: molecular cloning, characterization and expression analysis

Signal transducer and activators of transcription (STAT) gene, suppressors of cytokine signaling (SOCS) has been isolated from kuruma shrimp, Marsupenaeus japonicus and characterized. The kuruma shrimp STAT (MjSTAT) cDNA was composed of 2901 bp consisting of 801 amino acid residues which includes a protein interaction domain, all alpha domain, DNA binding domain and SH2 domain. Homology analysis of MjSTAT showed 94.1% and 34.0% identities with Penaeus monodon STAT (PmSTAT) and Drosophila melanogaster STAT92E (DmSTAT), respectively. The kuruma shrimp SOCS (MjSOCS) cDNA was composed of 1675 bp consisting of 342 amino acid residues including a SH2 domain and C-terminal SOCS domain. Homology analysis of MjSOCS showed 52.6% and 21.3% identities with Chinese mitten crab (Eriocheir sinensis) SOCS2 and fruit fly (D. melanogaster) SOCS44A, respectively. The MjSTAT and MjSOCS genes are constitutively expressed in the muscle, stomach, brain and gill of kuruma shrimp. In lymphoid organ cells, an enhanced expression of both MjSTAT and MjSOCS genes are observed following stimulation with peptidoglycan and polycytidylic acid. These observations suggest that MjSTAT and MjSOCS might play a major role in the innate immune defense of kuruma shrimp. The discovery of JAK/STAT signaling pathway in shrimp will allow a complete and concrete understanding of shrimp cytokine signaling.

Phylogenetic relationships among the family Ommastrephidae (Mollusca: Cephalopoda) inferred from two mitochondrial DNA gene sequences

Squids of the family Ommastrephidae are distributed worldwide, and the family includes many species of commercial importance. To investigate phylogenetic relationships among squid species of the family Ommastrephidae, partial nucleotide sequences of two mitochondrial gene loci (cytochrome c oxidase subunit I [1277bp] and 16S rRNA [443bp]) of 15 ommastrephid species and two outgroup species from the families Loliginidae and Enoploteuthidae were determined and used to construct parsimony and distance based phylogenetic trees. The molecular data provided several new phylogenetic inferences. The monophyletic status of three subfamilies (Illicinae, Todarodinae and Ommastrephinae) was well supported, although phylogenetic relationships between the subfamilies were not resolved. Inclusion of a problematic species, Ornithoteuthis volatilis, to Todarodinae was indicated. Within Todarodinae, the Japanese common squid Todarodes pacificus was observed to have much closer relationship to the species of the genus Nototodarus than to its congener (Todarodes filippovae). These results indicate that re-evaluation of several morphological key characters for ommastrephid taxonomy may be necessary.

Separation of EEG and ECG components based on wavelet shrinkage and variable cosine window

During ambulatory monitoring, it is sometimes required to record an electroencephalogram (EEG) and an electrocardiogram (ECG) simultaneously. It would be ideal if both EEG and ECG could be obtained with one measurement. Here, we introduce an algorithm that combines the wavelet shrinkage and variable cosine window operation to separate the EEG and ECG components from an EEG signal recorded with a noncephalic reference (NCR). Evaluation using simulated data and actual measured data showed that accurate frequency analysis of EEG and an R-R detection-based heart rate analysis were feasible with our proposed algorithm, which improved the signal-averaging based algorithm so that ECG components containing ectopic beats can be applied.

Proliferação de linfócitos e apoptose de células CD5+ de bovinos infectados pelo vírus da leucose enzoótica bovina

Avaliaram-se a proliferação de linfócitos e a apoptose de células CD5+ de bovinos naturalmente infectados pelo vírus da leucose enzoótica bovina. Para tal, 100 vacas da raça Holandesa, em lactação, foram triadas quanto ao sorodiagnóstico para a leucose enzoótica bovina e o perfil hematológico, e 15 foram escolhidos e distribuídos uniformemente entre os três grupos, a saber: animais negativos, animais positivos alinfocitóticos e animais positivos e que manifestaram linfocitose persistente (LP). Para a avaliação da proliferação de linfócitos, procedeu-se ao isolamento das células mononucleares por gradiente de centrifugação, em que 2x10(6) linfócitos por mL foram plaqueados por poço e analisados por citometria de fluxo utilizando-se o fluorocromo CFSE-DA. A apoptose do sangue periférico deu-se utilizando a anexina V-FITC, e para a identificação das células CD5+, utilizaram-se anticorpos monoclonais. Ocorreu menor proliferação de linfócitos nos animais infectados e que manifestavam LP, e menor apoptose de células CD5+ do sangue periférico. Pode-se sugerir que o desenvolvimento da LP, resultante do aumento de linfócitos B, deve-se à redução do processo apoptótico das células CD5+, principal população infectada, e que a maior proliferação linfocitária pode se restringir apenas ao estádio inicial do desenvolvimento da LP.

Molecular cloning, in vitro expression and functional characterization of canine ADAMTS13

A disintegrin and metalloproteinase with thrombospondin type 1 motifs, number 13 (ADAMTS13) is a plasma zinc metalloprotease also known as von Willebrand factor (VWF)-cleaving protease. Deficiency of ADAMTS13 activity is known to cause thrombotic thrombocytopenic purpura (TTP) in humans. We isolated the canine ADAMTS13 cDNA, which encodes 1502 amino acids, and expressed the recombinant protein to evaluate VWF-cleaving ability. Although the propeptide domain was longer and the TSP1 repeat domain was shorter than those in other species, the overall structures were similar to human and mouse ADAMTS13. Recombinant canine ADAMTS13 cleaved the 250-kDa VWF monomer into two fragments of 150 kDa and 120 kDa. Furthermore, high molecular weight VWF multimers were abolished based on the activity of ADAMTS13. These results could facilitate research into hemostatic disorders such as TTP in dogs.

Deciphering the DNA repair protein, Rad23 from kuruma shrimp Marsupenaeus japonicus: full-length cDNA cloning and characterization

AIMS

 Lesions of DNA are removed by nucleotide excision repair (NER) process in the living systems. NER process-related host factors are believed to aid recovery steps during viral integration. Here, we report identification and characterization of a DNA repair molecule Rad23 from kuruma shrimp Marsupenaeus japonicus.

METHODS AND RESULTS

The full-length cDNA of M. japonicus Rad23 gene (MjRad23) has 1149 bp coding for a putative protein of 382 amino acids with a 5' untranslated region (UTR) of 92 bp and 3' UTR region of 1116 bp. Quantitative expression analysis revealed MjRad23 is constitutively expressed in all the organs of healthy shrimp, whereas with high level in muscle tissue. Although MjRad23 expression is observed in every haemolymph samplings to post-white spot syndrome virus infection, high expression is recorded at 2 h post infection (h.p.i.). MjRad23 consists of putative functional domains including one ubiquitin domain (UBQ), two ubiquitin-associated domains (UBA) and one heat-shock chaperonin-binding motif (STI1). Multiple alignment of MjRad23 with Rad23 of other species showed highly significant identity ranging from 37 to 53%; however, high homology is observed with Rad23 of Bombyx mori (BmRad23). UBQ domain region alignment revealed maximum of 66% homology with Rad23 of Apis melifera (AmRad23). MjRad23 clustered with invertebrate sector along with insect species in evolution analysis. Three-dimensional structural analyses demonstrated the highest identity between MjRad23 and human Rad23A (hHR23A).

CONCLUSIONS

The present work revealed the presence of MjRad23 gene, which is essential in DNA repair process. Further studies are required to clarify the involvement of MjRad23 in NER process.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report on identification and characterization of DNA repair protein in crustaceans, which will lead to further investigation to explore the molecular mechanisms behind the NER process.

Diazepam decreases leukocyte-endothelium interactions in situ

High doses of diazepam reduce the inflammatory paw edema in rats. This effect was attributed to an action of diazepam on the Translocator Protein (TSPO). We evaluated the effects of diazepam (10 mg/kg, intraperitoneally) on leukocyte rolling and migration. In carrageenan-induced acute inflammation, diazepam decreased the interaction of leukocytes with endothelial cells (rolling) and the number of leukocytes in the mesentery (migration). RU486 (antagonist of glucocorticoid receptors) reduced the effects of diazepam on leukocyte rolling and migration, suggesting a participation of endogenous corticosteroids. We also showed that the effects of diazepam on leukocyte-endothelium interactions are mediated by nitric oxide (NO), since prior treatment with l-arginine (precursor of NO) partially precludes the inhibitory effects of diazepam; conversely, pretreatment with L-NAME (false substrate of the NO synthase) somewhat potentiates the effects of diazepam. The pathways that underlie the effects of diazepam remain to be further elucidated, but we believe that both local and systemic mechanisms may overlap to explain the influence of diazepam on leukocyte-endothelium interactions.

Expression of fibrosis-related genes in canine chronic hepatitis

Molecular regulation of fibrosis in chronic canine hepatitis is poorly understood. The authors employed quantitative polymerase chain reaction (PCR) to determine the expression levels of genes reported to be related to fibrosis in other species (human, mouse, and rat) and to elucidate the relationship of these genes with the degree of fibrosis and the presence or absence of ascites and/or jaundice in dogs with hepatitis. Nine fibrosis-related genes were assayed: PDGFB, PDGFD, MMP2, TIMP1, THBS1, COL1A1, COL3A1, TGFB1, and TGFB2. Liver samples of 15 dogs with chronic hepatitis and 4 healthy control dogs were obtained via laparoscopic biopsy and subjected to histologic and quantitative PCR analyses. The expression of all 9 genes showed significant positive correlation (P<.01, r>.70) with the degree of fibrosis. Furthermore, the expression levels of all genes except TGFB1 were significantly higher (P<.05) in dogs with hepatic failure-related symptoms (ascites/jaundice). Results suggest that these 9 genes are integral to the development of fibrosis in canine chronic hepatitis.

Detection of Renibacterium salmoninarum, the Causative Agent of Bacterial Kidney Disease in Salmonid Fish, from Pen-Cultured Coho Salmon

The detection of Renibacterium salmoninarum antigen from pen-cultured coho salmon was attempted. Flounder (Limanda herzensteini) (n = 24), greenling (Hexagrammos otakii) (n = 5), Japanese sculpin (Cottus japonicus) (n = 1), and flathead (Platycephalus indicus) (n = 22) captured by fishing around coho salmon net pens were examined for the presence of R. salmoninarum antigen by an indirect dot blot assay and by an indirect fluorescent-antibody technique using polyclonal and monoclonal antibodies. R. salmoninarum antigen was detected from kidney samples of one greenling and six flathead. Moreover, 86 scallops (Patinopecten yessoensis) were hung from the edge of the net pen for 50 days, and R. salmoninarum antigen was demonstrated in 31 samples by the indirect dot blot assay and the indirect fluorescent-antibody technique.

Chronic administration of DSP-7238, a novel, potent, specific and substrate-selective DPP IV inhibitor, improves glycaemic control and beta-cell damage in diabetic mice

AIMS

The purpose of this study is to assess the in vitro enzyme inhibition profile of DSP-7238, a novel non-cyanopyrrolidine dipeptidyl peptidase (DPP) IV inhibitor and to evaluate the acute and chronic effects of this compound on glucose metabolism in two different mouse models of type 2 diabetes.

METHODS

The in vitro enzyme inhibition profile of DSP-7238 was assessed using plasma and recombinant enzymes including DPP IV, DPP II, DPP8, DPP9 and fibroblast activation protein alpha (FAPalpha) with fluorogenic substrates. The inhibition type was evaluated based on the Lineweaver-Burk plot. Substrate selectivity of DSP-7238 and comparator DPP IV inhibitors (vildagliptin, sitagliptin, saxagliptin and linagliptin) was evaluated by mass spectrometry based on the changes in molecular weight of peptide substrates caused by release of N-terminal dipeptides. In the in vivo experiments, high-fat diet-induced obese (DIO) mice were subjected to oral glucose tolerance test (OGTT) following a single oral administration of DSP-7238. To assess the chronic effects of DSP-7238 on glycaemic control and pancreatic beta-cell damage, DSP-7238 was administered for 11 weeks to mice made diabetic by a combination of high-fat diet (HFD) and a low-dose of streptozotocin (STZ). After the dosing period, HbA1c was measured and pancreatic damage was evaluated by biological and histological analyses.

RESULTS

DSP-7238 and sitagliptin both competitively inhibited recombinant human DPP IV (rhDPP IV) with K(i) values of 0.60 and 2.1 nM respectively. Neither vildagliptin nor saxagliptin exhibited competitive inhibition of rhDPP IV. DSP-7238 did not inhibit DPP IV-related enzymes including DPP8, DPP9, DPP II and FAPalpha, whereas vildagliptin and saxagliptin showed inhibition of DPP8 and DPP9. Inhibition of glucagon-like peptide-1 (GLP-1) degradation by DSP-7238 was apparently more potent than its inhibition of chemokine (C-X-C motif) ligand 10 (IP-10) or chemokine (C-X-C motif) ligand 12 (SDF-1alpha) degradation. In contrast, vildagliptin and saxagliptin showed similar degree of inhibition of degradation for all the substrates tested. Compared to treatment with the vehicle, single oral administration of DSP-7238 dose-dependently decreased plasma DPP IV activity and improved glucose tolerance in DIO mice. In addition, DSP-7238 significantly decreased HbA1c and ameliorated pancreatic damage following 11 weeks of chronic treatment in HFD/STZ mice.

CONCLUSIONS

We have shown in this study that DSP-7238 is a potent DPP IV inhibitor that has high specificity for DPP IV and substrate selectivity against GLP-1. We have also found that chronic treatment with DSP-7238 improves glycaemic control and ameliorates beta-cell damage in a mouse model with impaired insulin sensitivity and secretion. These findings indicate that DSP-7238 may be a new therapeutic agent for the treatment of type 2 diabetes.

Molecular cloning and transcriptional analysis of a newly identified anti-lipopolysaccharide factor gene in kuruma shrimp, Marsupenaeus japonicus

AIM

In the present study, we have cloned a new family of anti-lipopolysaccharide factor (ALF) from haemocytes of kuruma shrimp Marsupenaeus japonicus (MjALF2) using RACE method.

METHODS AND RESULTS

Transcriptional analysis of MjALF2 gene in the organs of healthy shrimp revealed prominent expression in gills and muscle. In vitro LPS stimulation in the lymphoid organ cells resulted in significant increase in expression at 48, 8 and 12 h poststimulation, compared to the nonstimulated cells. In vivo injection of V. penaeicida does not show any high expression in time course assay. Phylogenetic analysis showed MjALF2 is placed in the group closer to P. monodon isoform 1 and 2 than to MjALF1. The full-length MjALF2 gene consists of 558 bp with a 363 -bp open reading frame, encoding 121 amino acids. The deduced peptide contains a putative signal peptide of 22 amino acids with molecular mass of about 13.8 kDa molecular mass. The deduced amino acid sequence of MjALF2 showed 83.3 and 56.7% identity with ALF sequences of P. monodon.

CONCLUSIONS

The present work revealed the presence of MjALF2 gene, which is highly expressed in gills and muscle of healthy kuruma shrimp. Further studies are required to clarify the involvement of MjALF2 in immune responses for using as a therapeutic agent.

SIGNIFICANCE AND IMPACT OF THE STUDY

Antimicrobial peptides are promising potential therapeutic agents for disease control in aquaculture. Understanding the relation of MjALF2 with innate immunity mechanism will lead to develop better health management strategies for long-term sustainability of the shrimp industry.