Molecular cloning and tissue distribution of glucokinase and glucose-6-phosphatase catalytic subunit paralogs in largemouth bass Micropterus salmoides: Regulation by dietary starch levels and a glucose load

The dysregulation of glucose-G6P (glucose-6-phosphate) interconversion is thought to be one of the main reasons for the low glucose disposal of carnivorous fish, but is not yet well understood in largemouth bass Micropterus salmoides (LMB). In this study, the full length cDNA sequences of genes encoding glucokinase (Gck, catalyzing glucose phosphorylation) and glucose-6-phosphatase catalytic subunit (G6pc, catalyzing glucose dephosphorylation) were cloned by the RACE method from the liver of LMB. Subsequently, the distribution of g6pc and gck as well as their transcriptional regulation by dietary starch levels and a glucose load were investigated. Only one gck gene was identified, while the tandem duplication of g6pca.1 gene was named as g6pca.2 in LMB. The full cDNA sequences of g6pca.1, g6pca.2 and gck in LMB were 1585, 1813 and 2115 bp in length, encoding 478, 352 and 359 amino acids, respectively. Gck was predicted to contain two hexokinase domains, an ATP-binding domain and multiple functional sites, while G6pca.1 and G6pca.2 contained nine transmembrane helices, a PAP2 (type-2 phosphatidic acid phosphatase) domain and multiple functional amino acid sites. Both g6pca.1 and g6pca.2 were predominantly distributed in the liver and to some extent in the intraperitoneal fat, intestine and pyloric caeca, while gck was mainly transcribed in the liver and to some extent in the heart, intestine and brain. Both feeding a high starch diet and a glucose load stimulated the mRNA expression of gck in the liver of LMB. An increase of dietary starch from 9% to 14% down-regulated the transcription of g6pca.1 in the liver of LMB. However, both the mRNA levels of hepatic g6pca.1 and g6pca.2 were sharply up-regulated in LMB during 1-3 h after a glucose load. Overall, the results of this study suggested that the functions of G6pc (G6pca.1 and G6pca.2) and Gck in LMB were highly conserved in evolution. Though hepatic glucose-G6P interconversion was well regulated at the transcript level in LMB fed high starch diets, a futile cycle between glucose and G6P was induced in the liver after a glucose load.

[Effect of recombinant human thrombin for hemostasis in liver resection: a randomized controlled phase Ⅲ clinical trial]

Objective: To evaluate the hemostatic efficacy, safety and immunogenicity of recombinant human thrombin in the treatment of liver wounds that still ooze after conventional surgical hemostasis. Methods: A multicenter, stratified randomized, double-blind, placebo-controlled phase Ⅲ trial with a planned enrollment of 510 subjects at 33 centers, with a 2∶1 randomization to the thrombin group versus the placebo group. An interim analysis will be conducted after approximately 70% of the subjects have completed the observation period. The primary efficacy endpoint was the rate of hemostasis within 6 minutes at the point of bleeding that could be evaluated. Safety analysis was performed one month after surgery, and the positive rates of anti-drug antibody (ADA) and neutralizing antibody were evaluated. Results: At the interim analysis, a total of 348 subjects had been randomized and received the study drug (215 were male and 133 were female). They were aged 19-69 (52.9±10.9)years. Among them, 232 were in the thrombin group and 116 were in the placebo group, with balanced and comparable demographics and baseline characteristics between the two groups. The hemostasis rate at 6 minutes was 71.6% (95%CI:65.75%-77.36%) in the thrombin group and 44.0% (95%CI: 34.93%-53.00%) in the placebo group, respectively (P<0.001). No grade≥3 drug-related adverse events and no drug-related deaths were reported from the study.No recombinant human thrombin-induced immunologically-enhanced ADA or immunologically-induced ADA was detected after topical use in subjects. Conclusion: Recombinant human thrombin has shown significant hemostatic efficacy and good safety in controlling bleeding during liver resection surgery, while also demonstrating low immunogenicity characteristics.

Molecular characterization of a teleost-specific toll-like receptor 22 (tlr22) gene from yellow catfish (Pelteobagrus fulvidraco) and its transcriptional change in response to poly I:C and Aeromonas hydrophila stimuli

Toll-like receptors (TLRs) are a class of pattern recognition receptors (PRRs) that can recognize pathogen-associated molecular patterns (PMPs) and play important roles in the innate immune system in vertebrates. In this study, we identified a teleost-specific tlr22 gene from yellow catfish (Pelteobagrus fulvidraco) and its immune roles in response to different pathogens were also determined. The open reading frame (ORF) of the tlr22 was 2892 bp in length, encoding a protein of 963 amino acids. Multiple protein sequences alignment, secondary and three-dimensional structure analyses revealed that TLR22 is highly conserved among different fish species. Phylogenetic analysis showed that the phylogenetic topology was divided into six families of TLR1, TLR3, TLR4, TLR5, TLR7 and TLR11, and TLR22 subfamily was clustered into TLR11 family. Meanwhile, synteny and gene structure comparisons revealed functional and evolutionary conservation of the tlr22 gene in teleosts. Furthermore, tlr22 gene was shown to be widely expressed in detected tissues except barbel and eye, with highest expression level in liver. The transcription of tlr22 was significantly increased in spleen, kidney, liver and gill tissues at different timepoints after Poly I:C infection, suggesting TLR22 plays critical roles in defensing virus invasion. Similarly, the transcription of tlr22 was also dramatically up-regulated in spleen, kidney and gill tissues with different patterns after Aeromonas hydrophila infection, indicating that TLR22 is also involved in resisting bacteria invasion. Our findings will provide a solid basis for the investigation the immune functions of tlr22 gene in teleosts, as well as provide useful information for disease control and treatment for yellow catfish.

Molecular Characterization and Expression Analysis of Intercellular Adhesion Molecule-1 (ICAM-1) Genes in Rainbow Trout (Oncorhynchus mykiss) in Response to Viral, Bacterial and Parasitic Challenge

The intercellular adhesion molecule-1 (ICAM-1), known as CD54, is a transmembrane cell surface glycoprotein that interacts with two integrins (i.e., LFA-1 and Mac-l) important for trans-endothelial migration of leukocytes. The level of ICAM-1 expression is upregulated in response to some inflammatory stimulations, including pathogen infection and proinflammatory cytokines. Yet, to date, our knowledge regarding the functional role of ICAM-1 in teleost fish remains largely unknown. In this study, we cloned and characterized the sequence of ICAM-1 in rainbow trout (Oncorhynchus mykiss) for the first time, which exhibited that the molecular features of ICAM-1 in fishes were relatively conserved compared with human ICAM-1. The transcriptional level of ICAM-1 was detected in 12 different tissues, and we found high expression of this gene in the head kidney, spleen, gills, skin, nose, and pharynx. Moreover, upon stimulation with infectious hematopoietic necrosis virus (IHNV), Flavobacterium columnare G₄ (F. columnare), and Ichthyophthirius multifiliis (Ich) in rainbow trout, the morphological changes were observed in the skin and gills, and enhanced expression of ICAM-1 mRNA was detected both in the systemic and mucosal tissues. These results indicate that ICAM-1 may be implicated in the mucosal immune responses to viral, bacterial, and parasitic infections in teleost fish, meaning that ICAM-1 emerges as a master regulator of mucosal immune responses against pathogen infections in teleost fish.

Molecular characterization of two leptin genes and their transcriptional changes in response to fasting and refeeding in Northern snakehead (Channa argus)

Leptin has been proved to play critical roles in energy metabolism, body weight regulation, food intake, reproduction and immunity in mammals. However, its roles are still largely unclear in fish. Here, we report two leptin genes (lepA and lepB) from the Northern snakehead (Channa argus) and their transcriptions in response to different feeding status. The snakehead lepA is 781 bp in length and contains a 480 bp open reading frame (ORF) encoding a 159-aa protein, while the snakehead lepB is 553 bp in length and contains a 477 bp ORF encoding a 158-aa protein. Multi-sequences alignment, three-dimensional (3D) model prediction, syntenic and genomic comparison, and phylogenetic analysis confirm two leptin genes are widely existing in teleost. Tissue distribution revealed that the two leptin genes exhibit different patterns. In a post-prandial experiment, the hepatic lepA and brain lepB showed a similar transcription pattern. In a long-term (2-week) fasting and refeeding experiment, the hepatic lepA and brain lepB showed a similar transcription change pattern induced by food deprivation stimulation but differential changes after refeeding. These findings suggest snakehead lepA and lepB are differential both in tissue distribution and molecular functions, and they might play as an important regulator in energy metabolism and food intake in fish, respectively.

Complete mitochondrial genome of Palaemonetes sinensis and its phylogenetic consideration

The aim of this study was to determine the complete mitochondrial genome (mitogenome) and the phylogenetic location of the Palaemonetes sinensis. The mitogenome was 15,736 bp in length, containing 22 transfer RNA genes (tRNAs), 13 protein-coding genes (PCGs), 2 ribosome RNA genes (rRNAs), and a control region (CR). The overall nucleotide composition is as follows: A, 35.69%; C, 21.66%; G, 12.39%; T, 30.26%. Nine and four PCGs were encoded on the heavy and light strands, respectively. Phylogenetic analysis suggested that P. sinensis shares a close relationship with Palaemon serenus and Palaemon capensis. These findings are helpful for better understanding the phylogenetic relationship among Caridea, as well as investigating the population genetics of P. sinensis in the future.

Complete mitochondrial genome of a kind of snakehead fish Channa siamensis and its phylogenetic consideration

The snakehead fish, Channa siamensis, belongs to the genus of Channa (perciformes: Channidae) and was first reported by Günther in 1861. Despite it has been described approximately for 15 decades, the genetic information is limited and the taxon status of this kind of fish is still unclear. The primary objective of this study is to get more genomic data and calculate the taxon location of this kind of fish. The next generation sequencing method was used to obtain the whole mitochondrial DNA information, and bioinformatic analysis was performed to investigate the evolutionary status and taxon location of C. siamensis. The circular mitochondrial DNA was 16,570 bp in length, and which showed typical piscine structure and arrangement. The overall nucleotide composition was 29.28% A, 24.72% T, 30.71% C, 15.29% G, with 54.1% AT, respectively. Phylogenetic analyses using concatenated amino acid and nucleotide sequences of the 13 protein-coding genes with two different methods (Maximum likelihood and Bayesian analysis) both highly supported C. siamensis belongs to the genus Channa and shows a close relationship with C. micropeltes. These data will provide more useful information for a better understanding of the mitochondrial genomic diversities and evolution in fish as well as novel genetic markers for studying population genetics and species identification.

Molecular cloning, tissue distribution, and effect of fasting and refeeding on the expression of neuropeptide Y in Channa argus

Neuropeptide Y (NPY) is a 36 amino-acid amidated peptide of the pancreatic polypeptide (PP) family, which plays an important role in appetite regulation and energy expenditure in mammals. Although several teleost NPY have been identified, its roles remain unclear in fish. We herein reported on the molecular cloning, tissue distribution and the effect of fasting on the expression of NPY in Channa argus, and designated as CaNPY. It consisted of a 300 bp open reading frame predicted to encode a prepro-NPY of 99 amino acids. Sequence analysis revealed that CaNPY was highly conserved (>60%) with other vertebrate NPY. Phylogenetic analysis highly supported CaNPY was closely related to piscine NPY. In addition, except for muscle and spleen tissues, CaNPY was found to extensively expressed in all other detected tissues, with the highest level in brain. Futhermore, the CaNPY transcript was found to significantly increase after short-term and long-term food deprivation, and dramatically decrease following refeeding. These findings suggested that CaNPY might be involved in food intake regulation and it could be as a potential target locus to improve commercial production of this kind of fish.

Molecular characterization of a cytosolic manganese superoxide dismutase from the Chinese mitten crab, Eriocheir sinensis

A cytosolic manganese superoxide dismutase gene (Es-cMnSOD) was cloned from the Chinese mitten crab Eriocheir sinensis, using reverse transcription-polymerase chain reaction and the rapid amplification of cDNA ends. The open reading frame of Es-cMnSOD is 867 bp in length and encodes a 288-amino acid protein without a signal peptide. The calculated molecular mass of the translated protein of Es-cMnSOD is 31.43 kDa, with an estimated isoelectric point of 6.30. The deduced amino acid sequence of Es-cMnSOD has similarities of 90, 89, 84, 87, and 81% to those of white shrimp Litopenaeus vannamei MnSOD, black tiger shrimp Penaeus monodon MnSOD, giant freshwater prawn Macrobrachium rosenbergii MnSOD, blue crab Callinectes sapidus MnSOD, and red swamp crayfish Procambarus clarkii MnSOD, respectively. Es-cMnSOD contains a manganese superoxide dismutase domain (DVWEHAYY) and 4 conserved amino acids responsible for binding manganese. Es-cMnSOD was expressed in the hemocytes, eyestalk, muscle, intestine, gill, and hepatopancreas. Es-cMnSOD transcripts in hemocytes of E. sinensis increased at 1.5 and 48 h after injection of Aeromonas hydrophila, indicating that the induction of the SOD system response occurred within a short period of time. This study suggests that MnSOD may play a critical role in crab immunity, allowing efficient activation of an early innate immune response in the crab.

The effect of aerobic exercise and Macrothele raven venom on tumor-bearing mice

Liver cancer is one of the most common cancers in the world. Macrothele raven venom, a complicated mixture of neurotoxic peptides, proteins and low molecular weight material, has antitumor properties, but its mechanism of action is unknown. Moderate exercise has been shown to shrink tumors and cause a remarkable reduction in the tumor growth rate. In this study, we examined the antitumor effect of Macrothele raven venom in combination with exercise on tumor-bearing mice. Our results demonstrate that aerobic exercise in combination with venom administered at different doses was much more effective in a mouse H22 hepatoma model compared to separate administration of the 2 treatments. The underlying mechanism of this effect may be related to the expression of various tumor suppressor factors.

Intervention of TLR4 signal pathway cytokines in severe liver injury with obstructive jaundice in rats

Obstructive jaundice is a common surgical disease and a variety of end-stage severe liver injuries still lack effective treatments. Compared to traditional liver transplantation therapy, herbal treatment is noninvasive and has fewer side effects. Research results have shown that a modified major decoction of bupleurum can reduce the toxic reaction of obstructive jaundice, even though the mechanism is unclear. A period of chronic exercise training can significantly reduce TLR4 expression in mononuclear cells and the secretion of inflammatory cell factors. Our study administered a modified major decoction of bupleurum in combination with exercise in rats with obstructive jaundice and the results indicated that applying a major bupleurum decoction in combination with moderately intense aerobic exercise showed a beneficial effect on adjusting the expression of liver inflammatory cytokines, which thus improved immunity and finally reduced the liver injury of rats with obstructive jaundice.

Bimetallic reactivity. One-site addition two-metal oxidation reactions using a di-Co(II) complex of a binucleating ligand with 5- and 6-coordinate sites

The preparation of an unsymmetrical binucleating ligand bearing a bridging oxadiazole ring flanked on one side by three ligands and on the other by four ligands is described. When bound to two metals, the ligand forms complexes where the metals are in 5- and 6-coordinate sites after the incorporation of an exogenous bridging ligand. A di-Co(2+) complex of this ligand has been prepared containing a hydroxide bridge. The complex is readily oxidized to the di-Co(3+) state by outer sphere electron transfer with ferrocenium ions. Addition of Br(2) or NO(2)(+) to the di-Co(2+) complex leads to the rapid formation of the di-Co(3+) bromo or nitro complexes, respectively. The ligand characteristics which allow for double oxidation with ferrocenium ions and for the one-site addition two-metal oxidations with Br(2) and NO(2)(+) are discussed in terms of mechanical coupling between the two metal sites.

Bimetallic reactivity. Preparation and properties of bimetallic complexes formed by binucleating ligands bearing 4- and 6-coordinate sites

Four binucleating ligands bearing 4- and 6-coordinate sites employing phenolate bridges have been prepared. Bimetallic copper(II) and nickel(II) complexes of some of these ligands have been isolated and characterized. Crystal structures of two of the copper(II) complexes have been determined. A monometallic manganese(II) complex of one of these ligands was isolated. Upon exposure to dioxygen, acetonitrile solutions of the complex in the presence of chloride ions lead to the formation of a manganese(IV) complex. The crystal structure of this complex is reported, and it is shown that the metal is in the 4-coordinate ligand site and is bound to two chloride ions.

Bimetallic reactivity. On the use of oxadiazoles as binucleating ligands

Two (1,3,4)-oxadiazole ligands have been prepared. In one case the oxadiazole ring is flanked by two o-aniline groups, and in the other case it is an extension of the first where the amines are condensed with 2-picolyl groups. A monometallic copper(II) complex of the former has been prepared, and its crystal structure was determined. A number of bimetallic copper(II), cobalt(II), and nickel(II) complexes of the di-deprotonated latter ligand were prepared and isolated. The crystal structure of the cobalt(II) complex bearing two acetate bridges is reported. The work demonstrates that the seldom-employed oxadiazole ring can be used effectively for generating bimetallic complexes.