Effects of dietary tryptophan on the antioxidant capacity and immune response associated with TOR and TLRs/MyD88/NF-κB signaling pathways in northern snakehead, Channa argus (Cantor, 1842).

Introduction: Dietary tryptophan (Trp) has been shown to influence fish feed intake, growth, immunity and inflammatory responses. The purpose of this study was to investigate the effect and mechanism of Trp on immune system of juvenile northern snakehead (Channa argus Cantor, 1842). Methods: A total of 540 fish (10.21 ± 0.11 g) were fed six experimental diets containing graded levels of Trp at 1.9, 3.0, 3.9, 4.8, 5.9 and 6.8 g/kg diet for 70 days, respectively. Results and Discussion: The results showed that supplementation of 1.9-4.8 g/kg Trp in diets had no effect on the hepatosomatic index (HSI) and renal index (RI), while dietary 3.9 and 4.8 g/kg Trp significantly increased spleen index (SI) of fish. Dietary 3.9, 4.8, 5.9 and 6.8 g/kg Trp enhanced the total hemocyte count (THC), the activities of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD). Malondinaldehyde (MDA) levels in the blood were significantly decreased by consuming 3.9 and 4.8 g/kg Trp. Fish fed with 3.0 and 3.9 g/kg Trp diets up-regulated interleukin 6 (il-6) and interleukin 8 (il-8) mRNA levels. The expression of tumor necrosis factor α (tnf-α) was highest in fish fed with 3.0 g/kg Trp diet, and the expression of interleukin 1ß (il-1ß) was highest in fish fed with 3.9 g/kg Trp diet. Dietary 4.8, 5.9 and 6.8 g/kg Trp significantly decreased il-6 and tnf-α mRNA levels in the intestine. Moreover, Trp supplementation was also beneficial to the mRNA expression of interleukin 22 (il-22). Additionally, the mRNA expression levels of target of rapamycin (tor), toll-like receptor-2 (tlr2), toll-like receptor-4 (tlr4), toll-like receptor-5 (tlr5) and myeloid differentiation primary response 88 (myd88) of intestine were significantly up-regulated in fish fed 1.9, 3.0 and 3.9 g/kg Trp diets, and down-regulated in fish fed 4.8, 5.9 and 6.8 g/kg Trp diets. Dietary 4.8 and 5.9 g/kg Trp significantly increased the expression of inhibitor of nuclear factor kappa B kinase beta subunit (ikkß) and decreased the expression of inhibitor of kappa B (iκbα), but inhibited nuclear transcription factor kappa B (nf-κb) mRNA level. Collectively, these results indicated that dietary 4.8 g/kg Trp could improve antioxidant capacity and alleviate intestinal inflammation associated with TOR and TLRs/MyD88/NF-κB signaling pathways.

Nrf2 pathway in vegetable oil-induced inflammation of large yellow croaker (Larimichthys crocea).

This study was conducted to investigate the effects and regulation of dietary vegetable oil (VO, enriched with α-linolenic acid [ALA] and linoleic acid [LNA]) on the nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor-κB (NF-κB) pathways in large yellow croaker. In vivo study showed that the VO diet significantly decreased the activity of antioxidant enzymes and antioxidant enzyme-related mRNA expression in the liver tissue, in comparison with the fish oil (FO) diet (P < 0.05). The suppression of antioxidant capacity might be due to the decrease of nuclear Nrf2 protein translocation, Nrf2 binding to antioxidant response element (ARE) sequences, and subsequently, antioxidant genes transcription as electrophoretic mobility shift assay (EMSA) and luciferase assay showed. VO-derivated ALA and LNA exerted a lower antioxidant capacity than FO-derivated DHA and EPA, characterized by significantly lower nucleus Nfr2 protein expression but significantly higher ROS production values in primary hepatocytes (P < 0.05). The pro-inflammatory genes (tumor necrosis factor α [TNFα] and interleukin 1ß [IL1ß]) expression was significantly higher in the liver tissue of fish fed the VO diet which might be due to the activation of the NF-κB pathway (P < 0.05). Knockdown of the Nrf2 gene negatively affected the anti-inflammatory effect of fatty acids by increasing the expression of TNFα and the IL1ß gene and nuclear p65 protein (P < 0.05). In general, the results indicated that dietary vegetable oil decreased antioxidant capacity but induced inflammatory responses through the Nrf2/NF-κB pathway.

A Supramolecular-Based Dual-Wavelength Phototherapeutic Agent with Broad-Spectrum Antimicrobial Activity Against Drug-Resistant Bacteria.

With the ever-increasing threat posed by the multi-drug resistance of bacteria, the development of non-antibiotic agents for the broad-spectrum eradication of clinically prevalent superbugs remains a global challenge. Here, we demonstrate the simple supramolecular self-assembly of structurally defined graphene nanoribbons (GNRs) with a cationic porphyrin (Pp4N) to afford unique one-dimensional wire-like GNR superstructures coated with Pp4N nanoparticles. This Pp4N/GNR nanocomposite displays excellent dual-modal properties with significant reactive-oxygen-species (ROS) production (in photodynamic therapy) and temperature elevation (in photothermal therapy) upon light irradiation at 660 and 808 nm, respectively. This combined approach proved synergistic, providing an impressive antimicrobial effect that led to the complete annihilation of a wide spectrum of Gram-positive, Gram-negative, and drug-resistant bacteria both in vitro and in vivo. The study also unveils the promise of GNRs as a new platform to develop dual-modal antimicrobial agents that are able to overcome antibiotic resistance.

Adipose tissue contributes to hepatic pro-inflammatory response when dietary fish oil is replaced by vegetable oil in large yellow croaker (Larimichthys crocea): An ex vivo study.

The shortage of fish oil (FO) leads to the extensive use of vegetable oil (VO) in marine fish diets. High replacement percentage of dietary FO by VO induced pro-inflammatory response of adipose tissue (AT) and liver tissue (LT) in large yellow croaker (Larimichthys crocea). Mammalian studies showed that the secretion of cytokines by AT affected the immune response of LT. To investigate whether or not the inflammation response of LT is related to AT in large yellow croaker, LT and AT cells from fish fed FO diet (FOL and FOA) and VO diet (VOL and VOA) were co-cultured in a trans-well system, which resulted in an assembly of the two cells types sharing the culture medium but being separated by the membrane of the insert. Co-culture of FOL and FOA was selected as the control group (FOL-FOA). Results indicated that, when compared with the control group, the expression of pro-inflammatory genes (toll like receptors [TLRs], tumour necrosis factor α [TNFα], interleukin 1ß [IL1ß], suppressor of cytokine signalling 3 [SOCS3] and cyclooxygenase 2 [COX2]) in FOL was significantly increased in the co-culture group of FOL and VOA (FOL-VOA), while the expression of anti-inflammatory genes (arginase I [ArgI] and transforming growth factor ß1 [TGFß1]) in FOL was significantly depressed. On the contrary, a significantly depressed expression of pro-inflammatory genes (TLRs, TNFα, IL1ß and COX2) and increased expression of anti-inflammatory genes (interleukin 10 [IL10]) in VOL was observed in the co-culture group of VOL and FOA (VOL-FOA) when compared with the co-culture group of VOL and VOA (VOL-VOA). The change of immune-related gene expressions in LT cells was attributed to nuclear factor κB (NF-κB) signalling since the expression of the p65 protein was observed to show a similar trend to the expression of pro-inflammatory genes. It is speculated that dietary VO increased the secretion of cytokines, which induced pro-inflammatory response in LT cells. These ex vivo results indicate that AT plays a vital role in LT pro-inflammatory response in fish fed VO diet.

Influence of a Dietary Vegetable Oil Blend on Serum Lipid Profiles in Large Yellow Croaker ( Larimichthys crocea).

Serum lipid metabolic responses are associated with certain metabolic disorders induced by dietary habits in mammals. However, such associations have not been reported in fish. Lipidomic analyses were performed to investigate fish lipid metabolic responses to a dietary vegetable oil (VO) blend and to elucidate the mechanism of how the dietary VO blend affects serum lipid profiles. Results showed that the dietary VO blend strongly affects serum lipid profiles, especially the ratio of triglyceride/phosphatidylcholine (TAG/PC), via inhibiting hepatic PC biosynthesis and facilitating hepatic and intestinal lipoprotein assembly. Studies in vitro suggested that changes of serum TAG/PC ratio may be partially attributed to altered fatty acid composition in diets. Additionally, the reduction of 16:0/18:1-PC induced by the dietary VO blend may play a role in abnormal lipid deposition through inhibiting PPARA-mediated activation of ß-oxidation. These findings suggested that the serum TAG/PC ratio might be a predictive parameter for abnormal lipid metabolism induced by dietary nutrition in fish.

Selenium-mediated protection in reversing the sensitivity of bacterium to the bactericidal antibiotics.

Inducing production of damaging reactive oxygen species (ROS) is an important criterion to distinguish the bactericidal antibiotics from bacteriostatic antibiotics. Selenoenzymes were generally recognized to be a powerful antioxidant capable of scavenging free radicals, protecting the cells from the harmful effects of ROS. Therefore, the present study was carried out to investigate the selenium (Se)-mediated protection in reversing antibiotic sensitivity and the role of selenoenzymes in alleviating the negative effects of oxidative stress. The cellular antioxidant activity of Se-enriched bacteria was analyzed, as well as intracellular ROS production and elimination when Se-enriched bacteria in the presence of various antibiotics. Compared to complete inhibition of the parental strain by bactericidal antibiotics, it only exhibited slight and reversible inhibition of Se-enriched Escherichia coli ATCC25922 and Staphylococcus aureus ATCC25923 at the same conditions, which indicated that intracellular selenium provided substantial protection against antibiotics. ROS generation caused by bactericidal antibiotics was confirmed by fluorescence spectrophotometry using 2', 7'-dichloro- uorescein diacetate (DCFH-DA) as substrate. The time course experiments of pretreatment with selenium showed significant decrease of ROS level at 2h. In summary, the present study provides experimental evidence supporting selenoenzymes has good scavenging effect to ROS and can protect bacteria from oxidative stress injury induced by bactericidal antibiotics.

Dietary vegetable oil suppressed non-specific immunity and liver antioxidant capacity but induced inflammatory response in Japanese sea bass (Lateolabrax japonicus).

High percentage of dietary vegetable oil (VO) induced negative effects on immunity in numerous fish species. The present study was conducted to investigate whether VO could exert anti-immunological effects by regulating non-specific immunity, liver antioxidant capacity and nuclear factor kappa beta (NF-κB) signaling in Japanese sea bass (Lateolabrax japonicus). Three iso-nitrogenous and iso-lipid diets were formulated by replacing 0% (FO, the control), 50% (FV) and 100% (VO) of fish oil with vegetable oil. Each diet was randomly fed to triplicate groups of fish for 10 weeks. Results showed that the alternative complement pathway (ACP) activity and the disease resistance were significantly lower in fish fed VO diets compared with the control group (P < 0.05). Liver superoxide dismutase (SOD), catalase (CAT) and glutathion peroxidase (GPx) enzyme activities, as well as total antioxidant capacity (T-AOC) significantly decreased in fish fed VO diets (P < 0.05). Meanwhile, significantly low level of liver SOD1 and CAT mRNA, nuclear factor erythroid 2-related factor 2 (Nrf2) of both mRNA and protein were observed in fish fed VO diets when compared with fish fed FO diets (P < 0.05). However, the transcription level of TNFα and IL1ß was significantly higher in the liver of fish fed VO diets, which might be attributed to the activation of NF-κB signaling pathway since the protein expression of p65, one of the key members of NF-κB family, was significantly increased (P < 0.05). These results suggested that dietary VO could lower the ACP activity, disease resistance and liver antioxidant capacity, but it could also exacerbate inflammatory response by activating NF-κB signaling pathway in Japanese sea bass.

Regulation of FADS2 transcription by SREBP-1 and PPAR-α influences LC-PUFA biosynthesis in fish.

The present study was conducted to explore the mechanisms leading to differences among fishes in the ability to biosynthesize long-chain polyunsaturated fatty acids (LC-PUFAs). Replacement of fish oil with vegetable oil caused varied degrees of increase in 18-carbon fatty acid content and decrease in n-3 LC-PUFA content in the muscle and liver of rainbow trout (Oncorhynchus mykiss), Japanese seabass (Lateolabrax japonicus) and large yellow croaker (Larimichthys crocea), suggesting that these fishes have differing abilities to biosynthesize LC-PUFAs. Fish oil replacement also led to significantly up-regulated expression of FADS2 and SREBP-1 but different responses of the two PPAR-α homologues in the livers of these three fishes. An in vitro experiment indicated that the basic transcription activity of the FADS2 promoter was significantly higher in rainbow trout than in Japanese seabass or large yellow croaker, which was consistent with their LC-PUFA biosynthetic abilities. In addition, SREBP-1 and PPAR-α up-regulated FADS2 promoter activity. These regulatory effects varied considerably between SREBP-1 and PPAR-α, as well as among the three fishes. Taken together, the differences in regulatory activities of the two transcription factors targeting FADS2 may be responsible for the different LC-PUFA biosynthetic abilities in these three fishes that have adapted to different ambient salinity.

Vegetable oil induced inflammatory response by altering TLR-NF-κB signalling, macrophages infiltration and polarization in adipose tissue of large yellow croaker (Larimichthys crocea).

High level of vegetable oil (VO) in diets could induce strong inflammatory response, and thus decrease nonspecific immunity and disease resistance in most marine fish species. The present study was conducted to investigate whether dietary VO could exert these anti-immunological effects by altering TLR-NF-κB signalling, macrophages infiltration and polarization in adipose tissue of large yellow croaker (Larimichthys crocea). Three iso-nitrogenous and iso-lipid diets with 0% (FO, fish oil, the control), 50% (FV, fish oil and vegetable oil mixed) and 100% (VO, vegetable oil) vegetable oil were fed to fish with three replicates for ten weeks. The results showed that activities of respiratory burst (RB) and alternative complement pathway (ACP), as well as disease resistance after immune challenge were significantly decreased in large yellow croaker fed VO diets compared to FO diets. Inflammatory response of experimental fish was markedly elevated by VO reflected by increase of pro-inflammatory cytokines (IL1ß and TNFα) and decrease of anti-inflammatory cytokine (arginase I and IL10) genes expression. TLR-related genes expression, nucleus p65 protein, IKKα/ß and IκBα phosphorylation were all significantly increased in the AT of large yellow croaker fed VO diets. Moreover, the expression of macrophage infiltration marker proteins (cluster of differentiation 68 [CD68] and colony-stimulating factor 1 receptor [CSF1R]) was significantly increased while the expression of anti-inflammatory M2 macrophage polarization marker proteins (macrophage mannose receptor 1 [MRC1] and cluster of differentiation 209 [CD209]) was significantly decreased in the AT of large yellow croaker fed VO diets. In conclusion, VO could induce inflammatory responses by activating TLR-NF-κB signalling, increasing macrophage infiltration into adipose tissue and polarization of macrophage in large yellow croaker.

[Relationship between regulation effect of salvia miltiorrhiza on AQP2 in kidney and promoting blood circulation and diuresis].

Partial nature of "promoting blood circulation and dieresis" of Salvia Miltiorrhizain was initially demonstrated by investigating the regulation effect of AQP2 expression in kidney of trauma blood stasis model rats with the Salvia Miltiorrhizain so as to provide guidance for its clinical deployment of administration. Random allocation was taken to averagely divide 30 SD rats into two groups: 10 rats in normal group and 20 rats in blood stasis syndrome group. Trauma blood stasis rat model was established by quantitatively beating. Then the rat model group was divided into model group and salvia group. After 7 days of treatment, the rat kidney AQP2 expression was detected, the content of urine AQP2 was compared and the damaged local muscle and kidney pathological changes were observed by immunohistochemical method and western blot method. Compared with that of the normal group, rats in model group had inflammatory cells infiltration, blood stasis and edema of the injured local muscles and up-regulated AQP2 expression, decreasing urinary output, and kidney tissues blood stasis and edema (P < 0.05). On the other hand, compared with that of the model group, those parameters of rats in salvia group were all decreasing except urine output (P < 0.05). Such result indicated that Salvia Miltiorrhiza can reduce trauma blood stasis rat content of urine AQP2 and down-regulated AQP2 expression in kidney tissue, so as to reduce the reabsorption of water by renal tubular and increase urine output. The promoting blood circulation effect of Salvia Miltiorrhizain can alleviate the degree of the damaged tissue edema and encourage urine drainage. This therapy is closely related to the effect of regulating AQP2 in kidney by salvia, so the purpose of this study by verifying "promoting blood circulation and diuresis" as the mechanism for the regulation effect of the salvia on AQP2 expression.

[Influence of liver function on pregnancy outcome of women with hepatitis B virus who receive individualized nutritional management].

OBJECTIVE: To evaluate the influence of liver function on pregnancy outcome of women who are infected with the hepatitis B virus (HBV) and who receive individualized nutrition management during the perinatal period. METHODS: A total of 210 pregnant women were enrolled for study between January 2011 and July 2013. The women were divided into the following groups according to self-selected participation in individualized nutritional treatment and management plans (n =87, observation group) or in routine prenatal care without any nutrition management plan (n =123, control group). Inter-group differences in pregnancy complications, liver function and perinatal outcome were assessed statistically. RESULTS: The following pregnancy complications were recorded during the study:hypertension disorder, gestational diabetes, anemia and fetal growth restriction; however, the rates of these complications were significantly lower in the observation group than in the control group (P less than 0.05). The observation group also had significantly lower incidence rates of preterm labor, fetal distress and neonatal asphyxia (P less than 0.05). The observation group also had significantly lower proportions of hypoalbuminemia and abnormal liver function, and correlation analysis indicated that birth weight is correlated with the pregnant woman's energy and protein intake. CONCLUSION: Women with HBV can benefit from individualized nutrition management during the prenatal period, experiencing improved pregnancy outcome and reduced occurrence of pregnancy complications. The application of individualized and balanced nutrition management had no effect on fetal growth and development.

Regulation of tissue LC-PUFA contents, Δ6 fatty acyl desaturase (FADS2) gene expression and the methylation of the putative FADS2 gene promoter by different dietary fatty acid profiles in Japanese seabass (Lateolabrax japonicus).

The present study was conducted to evaluate the influences of different dietary fatty acid profiles on the tissue content and biosynthesis of LC-PUFA in a euryhaline species Japanese seabass reared in seawater. Six diets were prepared, each with a characteristic fatty acid: Diet PA: Palmitic acid (C16:0); Diet SA: Stearic acid (C18:0); Diet OA: Oleic acid (C18:1n-9); Diet LNA: α-linolenic acid (C18:3n-3); Diet N-3 LC-PUFA: n-3 LC-PUFA (DHA+EPA); Diet FO: the fish oil control. A 10-week feeding trial was conducted using juvenile fish (29.53 ± 0.86 g). The results showed that Japanese seabass had limited capacity to synthesize LC-PUFA and fish fed PA, SA, OA and LNA showed significantly lower tissue n-3 LC-PUFA contents compared to fish fed N-3 LC-PUFA and FO. The putative gene promoter and full-length cDNA of FADS2 was cloned and characterized. The protein sequence was confirmed to be homologous to FADS2s of marine teleosts and possessed all the characteristic features of microsomal fatty acid desaturases. The FADS2 transcript levels in liver of fish fed N-3 LC-PUFA and FO were significantly lower than those in fish fed other diets except LNA while Diet PA significantly up-regulated the FADS2 gene expression compared to Diet LNA, N-3 LC-PUFA and FO. Inversely, fish fed N-3 LC-PUFA and FO showed significantly higher promoter methylation rates of FADS2 gene compared to fish fed the LC-PUFA deficient diets. These results suggested that Japanese seabass had low LC-PUFA synthesis capacity and LC-PUFA deficient diets caused significantly reduced tissue n-3 LC-PUFA contents. The liver gene expression of FADS2 was up-regulated in groups enriched in C16:0, C18:0 and C18:1n-9 respectively but not in the group enriched in C18:3n-3 compared to groups with high n-3 LC-PUFA contents. The FADS2 gene expression regulated by dietary fatty acids was significantly negatively correlated with the methylation rate of putative FADS2 gene promoter.

[The proliferating ability inhibited by energy controllable steep pulse in breast cancer cell line and its mechanism].

This was a study aimed to observe the proliferating ability inhibited by energy controllable steep pulse (ECSP) and to detect the expression of gene with relation to the proliferating ability of the tumor in breast cancer cell line; the possible mechanisms were also addressed. Human breast cancer cell line MDA-MB-231 was treated with ECSP; the apoptosis and the expression of tumor suppressor gene--Rb genes and E2F1 genes in ECSP group and control group were detected by TUNEL staining and Reverse Transcripitional PCR respectively. ECSP was found to inhibit the proliferating ability of breast cancer cells markedly, the cell amount in ECSP group decreased and the TUNEL positive cells increased obviously, compared to control; 24 hours after treatment the expression of Rb genes mRNA increased, whereas the expression of E2F1 mRNA decreased. These findings indicate that the proliferating ability of breast cancer cells can be inhibited by ECSP markedly, the apoptosis of breast cancer cell can be induced by ECSP, and the Rb genes and E2F1 genes may be involved in the course.

[Steep pulse changes the expression of tissue factor in ovarian tumor].

As a micro-wound and target-aimed technology without special limitation, Electric Pulses have been widely researched in tumor treatment and the effects have been demonstrated by a series of experiments, yet the mechanism has not been explained clearly. In this experiment, energy controllable steep pulse (ECSP) was used to treat nude mice bearing human ovarian tumor, and the result was compared with that of the control group. The expression of an important coagulant factor-tissue factor (TF) was analyzed, as TF was also a tumor indicator of invasion and metastasis, the result may indicate the relationship among ECSP, thrombosis and tumor invasion. In this study, to shed light on the mechanism of tumor treatment in electrical fields, nude mice bearing ovarian tumors were randomly divided into the treated group and the untreated group. We treated the former group and took out the tumor instantly. The thrombosis and necrosis of ovarian tumor were observed under microscope. The expression of TF was analyzed by SP immunohistochemistry and RT-PCR. Lower level of TF expression was noticed in the tumor tissue treated by ECSP, and more apparent thrombosis was also seen in this group. The results make it clear that ECSP can accelerate thrombosis and consume coagulant factors such as TF, and that low expression of TF in tumor tissue can cut out the signal paths of tumor invasion. So it is suggested that ECSP may restrain tumor invasion and metastasis by modulating thrombosis.