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Changes in the metabolic profile within the intestine of lenok (Brachymystax lenok) when challenged to acute and lethal heat stress (HS) are studied using no-target HPLC-MS/MS metabonomic analysis. Of 51 differentially expressed metabolites identified in response to HS, 34 occurred in the positive ion mode and 17 in negative ion mode (VIP > 1, P < 0.05). Changes in metabolites (i.e. alpha-D-glucose, stachyose and L-lactate) related to carbohydrate and glycolysis are identified in HS-treated lenok. Fatty acid β-oxidation in HS-treated lenok was inhibited by accumulation of acetyl carnitine, palmitoylcarnitine, carnitine, and erucic acid. Many amino acids (L-tryptophan, D-proline, L-leucine, L-phenylalanine, L-aspartate, L-tyrosine, L-methionine, L-histidine and L-glutamine) decreased to support energy demands in HS-treated lenok. Oxidative damage in HS-treated lenok was indicated by decreased glycerophospholipid metabolites (i.e. glycerophosphocholine, 1-palmitoyl-2-hydroxy-sn-glycero-3-phosphoethanolamine, 1-palmitoyl-sn-glycero-3-phosphocholine, 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine, and 1, 2-dioleoyl-sn-glycero-3-phosphatidylcholine), and increased oxylipin production (12-HETE and 9R, 10S-EpOME). Oxidative stress increased formation of eicosanoids and dicarboxylic acids, overwhelming the mitochondrial β-oxidation pathway, while minor oxidative pathways (omega-oxidation and peroxisomal beta-oxidation) were likely to be activated in HS-treated lenok.

We assessed the acute and chronic effects of copper (Cu2+) on the antioxidant system in golden trout (Oncorhynchus mykiss aguabonita). The median lethal concentration after 96 h was determined as 0.24 mg L−1. We then used 0.06 (L) and 0.12 mg L−1 (H) Cu2+ to assess the responses of the antioxidant system to long-term exposure. The activities of superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase, glutathione reductase, reduced glutathione, and oxidized glutathione were measured in gill and liver tissue after 24 and 72 h and 7, 14, 21, and 28 days of exposure, as well as after 16 days of recovery in Cu2+-free water. Cu2+ accumulated to a greater extent in the liver than in the gill (0.61–0.75 mg kg−1 vs. 24.0–69.9 mg kg−1 in L group and 0.98–1.47 mg kg−1 vs. 33.3–66.03 mg kg−1 in H group). In the gill, we observed increases in the activities of superoxide dismutase, catalase, and glutathione peroxidase, as well as in the concentrations of reduced glutathione and oxidized glutathione. In the liver of L group, we observed increases in glutathione reductase activity and in the levels of reduced glutathione and oxidized glutathione. In L group, the activity of superoxide dismutase and reduced glutathione content increased after 24 h and then decreased over time, while catalase and glutathione reductase activity and oxidized glutathione levels increased. Data from the recovery period indicated that higher concentrations of Cu2+ may induce irreversible oxidative damage to the gill of golden trout.

Despite the broad knowledge of copper-induced stress and toxicity, data on the physiological responses to acute copper exposure and the correlation of those activities to a generalized stress response are still limited. The present study aimed to assess the physiological responses of golden trout to overcome copper stress at concentrations of 60 µg/L and 120 µg/L after 96 h, respectively. The activities of glucose-6-phosphate dehydrogenase (G6PD) phosphoenolpyruvate carboxykinase (PEPCK) and NADPH/NADP

Phosphorus (P) has been predicted to possess many two-dimensional (2D) allotropes, which have attracted intensive research attention due to their excellent properties and application promises. While only 2D black P films have been successfully obtained by the exfoliation method, fabrication of other phosphorus structures by epitaxial growth remains challenging. Recently, the metal-phosphorus network (MPhoN), a superstructure consisted of P and metal atoms has been realized, which offers a wider platform to study P and related compounds. In this paper, we report the observation of platinum-phosphorus networks obtained by P adsorption on Pt(111). Our findings not only enrich the diverse structures of the MPhoN family but also provide insights into the formation mechanism of epitaxial P and its interaction with the noble metal substrate.

To estimate the carbon source-sink function of mariculture ponds without a food supply, we analyzed carbon budgets and gaseous carbon fluxes in shrimp Marsupenaeus japonicus-sea cucumber Apostichopus japonicus polyculture seawater ponds (PSPs) without feeding. Over a 1 yr cycle, the total organic carbon outflow accounted for 78.6% of the inflow organic carbon in PSPs. Approximately 1558.1 kg ha-1 of organic carbon accumulated in PSPs, and the ratio of gaseous carbon exchange to carbon burial ranged from 0.73 to 1.45. The PSPs acted as a purification system where organic carbon is eliminated from the inflow water, and carbon retention in the sediment of such systems could offset their carbon emissions into the atmosphere.

We investigated the impacts of carbon dioxide (CO

Various miRNAs have been reported to regulate the chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs); however, whether miR-134 plays a role in this biological process remains undetermined. In the present study, we first evaluated the chondrogenic differentiation of BMSCs by Alcian blue staining, and examined the miR-134 expression by quantitative real-time PCR (qRT-PCR) during this process. And miR-134 inhibitor was used to investigate the functions of miR-134 in chondrogenic differentiation of BMSCs by Alcian blue staining, qRT-PCR, and Western blot. Subsequently, the correlation between miR-134 and SMAD6 was assessed via bioinformatics analysis and dual-luciferase reporter assay. Finally, the role of SMAD6 in chondrogenic differentiation of BMSCs was also determined through Alcian blue staining, qRT-PCR, and Western blot. As results showed that miR-134 expression was significantly down-regulated during chondrogenic differentiation, and inhibition of miR-134 obviously promoted chondrogenic differentiation. Dual-luciferase reporter assay indicated that miR-134 could directly target the 3′-UTRs of SMAD6, inhibit miR-134 expression in BMSCs, and up-regulate SMAD6 expression. Moreover, we found that overexpression of SMAD6 significantly promoted chondrogenic differentiation, and that SMAD6-induced promotion of chondrogenic differentiation could be reversed by miR-134 mimics. In conclusion, our findings suggest that miR-134 may act as a negative regulator during chondrogenic differentiation of BMSCs by interacting with SMAD6.

The sarcolemmal ATP-sensitive K+ (sarcKATP) channel plays a cardioprotective role during stress. However, the role of the sarcKATP channel in the apoptosis of cardiomyocytes and association with mitochondrial calcium remains unclear. For this purpose, we developed a model of LPS-induced sepsis in neonatal rat cardiomyocytes (NRCs). The TUNEL assay was performed in order to detect the apoptosis of cardiac myocytes and the MTT assay was performed to determine cellular viability. Exposure to LPS significantly decreased the viability of the NRCs as well as the expression of Bcl-2, whereas it enhanced the activity and expression of the apoptosis-related proteins caspase-3 and Bax, respectively. The sarcKATP channel blocker, HMR-1098, increased the apoptosis of NRCs, whereas the specific sarcKATP channel opener, P-1075, reduced the apoptosis of NRCs. The mitochondrial calcium uniporter inhibitor ruthenium red (RR) partially inhibited the pro-apoptotic effect of HMR-1098. In order to confirm the role of the sarcKATP channel, we constructed a recombinant adenovirus vector carrying the sarcKATP channel mutant subunit Kir6.2AAA to inhibit the channel activity. Kir6.2AAA adenovirus infection in NRCs significantly aggravated the apoptosis of myocytes induced by LPS. Elucidating the regulatory mechanisms of the sarcKATP channel in apoptosis may facilitate the development of novel therapeutic targets and strategies for the management of sepsis and cardiac dysfunction.

We investigated the impacts of carbon dioxide (CO2)-induced acidification on energy metabolism in muscle tissue of rainbow trout Oncorhynchus mykiss fry. Fry were exposed to freshwater in equilibrium with air containing CO2 at volume concentrations of 380, 1000 and 2000 ppm for 30 days. At this critical and sensitive life stage, we showed dose-dependent reductions in weight gain and changes in energy metabolism under projected future CO2 levels. Rainbow trout fry exposed to elevated CO2 concentrations produced more energy in muscle tissue because ATP levels were significantly elevated. Fry exposed to 1000 ppm CO2 had a higher activity of pyruvate kinase (PK), higher concentrations of pyruvate, acetate, 2-oxoglutarate, phenylalanine, tyrosine, inosine, uracil and uridine, and lower concentrations of anserine and IMP in muscle tissue based on metabolomic analysis. We infer that the increased ATP production in fry exposed to 1000 ppm CO2 is produced through glycolysis. In the 2000 ppm group, the protein content of muscle was lower than in the control, and the activities of PK, cytochrome C oxidase (COX), Na+/K+-ATP and Ca2+/Mg2+-ATPase were significantly higher. Concentrations of pyruvate, 2-oxoglutarate, histidine, anserine and IMP were significantly lower, and alanine, methionine, leucine, isoleucine, valine, lysine, pantothenate, uracil and inosine were significantly higher. Accelerated tissue decomposition may have sustained the higher production of ATP in the 2000 ppm group.

The Fatty acid-binding proteins (FABP) is a 14-15kDa intracellular protein which belong to large multigene family of intracellular lipid-binding proteins and play a important role in lipid uptake, transport lipid homeostasis. In this study, the rainbow trout FABP7 (GenBank accession No. JN413683) and actin (GenBank accession No. AF330142) were used to design primers for analyzing the expression during temperature challenge using qRT-PCR approach. The FABP7 are detected in liver, intestine and spleen in triploid, golden and diploid rainbow trout. After the temperature dropped from 10°C to 3°C, the relatively expression peaks at 6hr(triploid), 12hr (golden) in liver and 2hr (diploid) in intestine, the FABP7 reduced from 2hr and 6hr to 24hr in diploid and triploid rainbow trout in intestine, the FABP7 increased from 0hr to 24hr in diploid rainbow trout. After the temperature raise from 10°C to 18°C, the relatively expression peaks at 24hr (triploid) in intestine and 24hr (golden) in spleen, the FABP7 reduced from 2hr to 12hr (diploid and triploid) in intestine and 2hr to 12hr (diploid) and from and 0hr to 6hr (triploid) in spleen, the FABP7 increased from 2hr to 12hr (golden) in intestine. Overall, these results demonstrate the expression of FABP was received impact by changes of temperature.

Quantitative real-time PCR (qRT-PCR) is a highly sensitive, repeatable and high throughput technique for quantifying gene expression from diverse experimental conditions; Reference genes (R-genes) are commonly used to normalise qRT-PCR results. However, the expression levels of R-genes are not always stable under experimental conditions and should therefore be confirmed before being used as controls. In our study, we analysed the stability of eight commonly used genes, namely, GAPDH, 18S rRNA, 28S rRNA, ACTB, B2M, TUBA, Eef1a and P0, as references to accurately normalise the data of qRT-PCR. Seven tissues (heart, spleen, intestine, liver, ovary, testis and muscle) were analysed using qRT-PCR to confirm the stability of the eight R-genes pre- and post-bacterial infection, and the data were analysed by geNorm and NormFinder. Pre-bacterial infection, geNorm identified 18S rRNA as the most stable gene across the tissue types, while NormFinder identified P0; post-bacterial infection, 18S rRNA/Eef1a (in intestine) and GAPDH/P0 (in ovary) were the most stable pairs of genes identified by both geNorm and NormFinder. These results reveal that the expression stability of potential reference genes in O. macrolepis was affected under bacterial infection conditions.

One Acyl-CoA binding protein(ACBP) encoding gene was isolated from testis of Onychostoma macrolepis using homologous cloning and the RACE method. The full Oma-ACBP cDNA(GenBank accession no: JN254628) was 503 bp long and comprised 37 bp of the 5'-Untranslated Regions(UTR), 267 bp of the coding sequence(CDS) encoding a 88 amino acid proteins, and 199 bp of the 3'- Untranslated Regions(UTR) with the polyA tail. A condensed phylogenetic tree show that Oma-ACBP had similarities with vasas of fish species and even mammal and amphibian species, The Oma-ACBP shared 92% sequenced identity with Cyprinus carpio and 91% with Carassius auratus, including a conserved FABP domain, the result enriches our understanding in the study of sequence classification in Onychostoma macrolepis. The Quantitative real-time PCR analysis demonstrated that Oma-ACBP was highly expressed in intestine, spleen and liver, but weakly in testis, ovary, heart, brain, cheek, muscle and eye. It was highly expressed in liver and spleen(42% of dietary protein), weakly expressed in intestine (52% of dietary protein). In starvation challenge, the expression was weakly expressed from 5 day to 8 day, and highly expressed from 3 day to 5 day, and the expression kept stabilizing until the end of the experiment.

To construct a recombinant adenovirus vector carrying KATP; channel mutant subunit Kir6.2AAA and express it in rat cardiomyocytes.Based on the primers for Kir6.2 subunits, Kir6.2 GFG amino acids were site-directed mutated into AAA by means of overlap PCR. PCR products were cloned into pShuttle vector for sequence analysis. After Pme I linearization, it was transformed into adenovirus expression vector pAdEasy-1. Then the pAdEasy-1 was packaged into liposome and transfected into primary cultured rat cardiomyocytes. The expression of Kir6.2AAA was confirmed by reverse transcription PCR(RT-PCR) and Western blotting.The recombinant adenovirus carrying the gene fragment Kir6.2AAA and EGFP was constructed successfully, and the virus titer was 2.64×10(11); VP/mL. After infected by the recombinant adenovirus expressing Kir6.2AAA, rat cardiomyocytes expressed EGFP and emitted green fluorescence under a fluorescence microscope. RT-PCR demonstrated that the expression of Kir6.2AAA was significantly up-regulated in the infected cardiomyocytes, and Western blotting also proved the over-expression of Kir6.2AAA in the cardiomyocytes.The recombinant adenovirus carrying the gene fragment Kir6.2AAA and EGFP was constructed successfully and expressed correctly in rat cardiomyocytes.

The effects of temperature on SDA of taimen (Hucho taimen, Pallas) was evaluated, by measuring the temporal pattern of the oxygen consumption rates of taimen, after feeding, at four constant temperatures, 11.5, 14.5, 17.5, 20.5 °C. Peak VO2 increased linearly as temperature increased. Two peaks were observed during the SDA response at 11.5 °C, and it may be mainly resulted of mechanical SDA and biochemical of SDA when temperature was low enough. SDAE increased slowly to the maximum at 17.5 °C, and then decreased at 20.5 °C. The relationship between SDAE (kJ · kg−1) and temperature (t, °C) was described as: SDAE = − 0.1163t2 + 3.771t − 22.467, (R2 = 0.9999, n = 12, P < 0.001). The result showed that the optimum growth temperature of taimen occurred at 17.5 °C.

Specific Dynamic Action (SDA), the metabolic phenomenon resulting from the digestion and assimilation of a meal, is generally influenced by body mass. The effects of body mass on SDA of taimen (Hucho taimen, Pallas) was evaluated, by measuring the temporal pattern of the oxygen consumption rates of taimen with body masses, 38, 31, 24, 17, 10 g, after feeding, at 17.5 °C, Factorial scope of peak VO2, Duration and SDAE had a tendency to decrease with reduced body mass.

An ergodic process Q is constructed such that the divergence-rate D(P ‖ Q) is zero for all stationary processes P. The process Q is constructed using the cutting and stacking method.

Specific dynamic action (SDA), the metabolic phenomenon resulting from the digestion and assimilation of a meal, is generally influenced by temperature. The effects of temperature (5.5±0.5, 8.5±0.5, 11.5±0.5, 14.5±0.5, 17.5±0.5°C) on SDA of brook trout (Salvelinus fontinalus Mitchill) was evaluated, by measuring the temporal pattern of the oxygen consumption rates, after feeding. Peak VO 2 (highest recorded oxygen consumption rate following feeding) and SDAE (energy expended on SDA) increased slowly to a maximum at 14.5±0.5°C, and then decreased at 17.5±0.5 °C. The relationships between Peak VO 2 (mg·kg−1·h−1), the SDA E (kJ·kg−1) and temperature (t, °C) were respectively described as: Peak VO 2 = −0.1332t4 + 5.6612t3 −86.317t2 + 581.33t − 1275.3, SDA E = −23.59t4 + 999.28t3 − 15303t2 + 101913t − 229665 (n=650, R2 = 1, 4.5

The RNA helicase vasa is a member of the DEAD box protein family that plays an indispensable role in germcell and differentiation of reproductive system. In this study, vasa encoding genes was isolated from gonads of largescale shoveljaw fish (Onychostoma macrolepis) using homologous cloning and the RACE method. The complete cDNA of vasa gene (Gene Bank: HQ412513) contains a 760bp 5' Untranslated Regions (UTR), 1848 bp open reading frame (ORF), encoding 616 amino acids are predicted and 116 bp 3' Untranslated Regions (UTR). A condensed phylogenetic tree was constructed based on the amino acid sequences of the vasa and well-defined vertebrate vasa. The overall topology of the tree showed that the vasa in Onychostoma macrolepis clusters vasa had similarities with vasas of other species. The result enriches our understanding on the high level conservation of the amino acid sequence in the largescale shoveljaw fish. The largescale shoveljaw fish vasa shared 93% sequenced identity with Carassius auratus. The quantitative real-time PCR (qRT-PCR) analysis demonstrated that the vasa encoding gene was detected in intestine, heart, testis, liver, muscle, spleen, brain, cheek, ovary, and mainly detected in testis. During the different concentration of Estradiol, the tesitis vasa mRNA was weakly expressed from the dosage of 8 to 22μg/g body mass (p