Heterologous Expression and Characterization of a pH-Stable Chitinase from Micromonospora aurantiaca with a Potential Application in Chitin Degradation.

To promote the bioconversion of marine chitin waste into value-added products, we expressed a novel pH-stable Micromonospora aurantiaca-derived chitinase, MaChi1, in Escherichia coli and subsequently purified, characterized, and evaluated it for its chitin-converting capacity. Our results indicated that MaChi1 is of the glycoside hydrolase (GH) family 18 with a molecular weight of approximately 57 kDa, consisting of a GH18 catalytic domain and a cellulose-binding domain. We recorded its optimal activity at pH 5.0 and 55 °C. It exhibited excellent stability in a wide pH range of 3.0-10.0. Mg2+ (5 mM), and dithiothreitol (10 mM) significantly promoted MaChi1 activity. MaChi1 exhibited broad substrate specificity and hydrolyzed chitin, chitosan, cellulose, soluble starch, and N-acetyl chitooligosaccharides with polymerization degrees ranging from three to six. Moreover, MaChi1 exhibited an endo-type cleavage pattern, and it could efficiently convert colloidal chitin into N-acetyl-D-glucosamine (GlcNAc) and (GlcNAc)2 with yields of 227.2 and 505.9 mg/g chitin, respectively. Its high chitin-degrading capacity and exceptional pH tolerance makes it a promising tool with potential applications in chitin waste treatment and bioactive oligosaccharide production.

Omega-3 polyunsaturated fatty acids (n-3 PUFAs), somatic and fatigue symptoms in cardiovascular diseases comorbid major depressive disorder (MDD): A randomized controlled trial.

INTRODUCTION: Cardiovascular diseases (CVDs) and major depressive disorder (MDD) are the two most disabling diseases. Patients with CVDs comorbid depression had somatic and fatigue symptoms and were associated with chronic inflammation and omega-3 polyunsaturated fatty acid (n-3 PUFA) deficits. However, there have been limited studies on the effects of n-3 PUFAs on somatic and fatigue symptoms in patients with CVDs comorbid MDD. METHOD: Forty patients with CVDs comorbid MDD (58% males, mean age of 60 ± 9 years) were enrolled and randomised to receive either n-3 PUFAs (2 g of eicosapentaenoic acid [EPA] and 1 g of docosahexaenoic acid[DHA] per day) or placebo in a 12-week double-blind clinical trial. We assessed the somatic symptoms with Neurotoxicity Rating Scale (NRS) and fatigue symptoms with Fatigue Scale at baseline, weeks 1, 2, 4, 8 and 12, as well as blood levels of Brain-Derived Neurotrophic Factor (BDNF), inflammatory biomarkers and PUFAs, at the baseline and week 12. RESULTS: The n-3 PUFAs group had a greater reduction in Fatigue scores than the placebo group at Week 4 (p =.042), while there were no differences in the changes of NRS scores. N-3 PUFAs group also had a greater increase in EPA (p =.001) and a greater decrease in total n-6 PUFAs (p =.030). Moreover, in the subgroup analyses in the younger age group (age < 55), the n-3 PUFAs group had a greater reduction on NRS total scores at Week 12 (p =.012) and NRS Somatic scores at Week 2 (p =.010), Week 8 (p =.027), Week 12 (p =.012) than the placebo group. In addition, the pre- and post-treatment changes of EPA and total n-3 PUFAs levels were negatively associated with the changes of NRS scores at Weeks 2, 4, and 8 (all p <.05), and the changes of BDNF levels were negatively associated with NRS scores at Weeks 8 and 12 (both p <.05) in the younger age group. In the older age group (age ≥ 55), there were a lesser reduction on NRS scores at Weeks 1, 2 and 4 (all p <.05), but a greater reduction on Fatigue score at Week 4 (p =.026), compared to the placebo group. There was no significant correlation between the changes of blood BDNF, inflammation, PUFAs and NRS and Fatigue scores in general and in the older age group. CONCLUSION: Overall, n-3 PUFAs improved the fatigue symptoms in patients with CVDs comorbid MDD and the general somatic symptoms in specific subpopulation of younger age patients, and perhaps via the interplay between BDNF and EPA. Our findings provide promising rationales for future studies to investigate the treatment effects of omega-3 fatty acids on fatigue and somatic symptoms of chronic mental and medical diseases.

Determination of D-serine and D-alanine Tissue Levels in the Prefrontal Cortex and Hippocampus of Rats After a Single Dose of Sodium Benzoate, a D-Amino Acid Oxidase Inhibitor, with Potential Antipsychotic and Antidepressant Properties.

The effects of the N-methyl-D-aspartate receptor activators D-serine, D-alanine, and sarcosine against schizophrenia and depression are promising. Nevertheless, high doses of D-serine and sarcosine are associated with undesirable nephrotoxicity or worsened prostatic cancer. Thus, alternatives are needed. DAAO inhibition can increase D-serine as well as D-alanine and protect against D-serine-induced nephrotoxicity. Although several DAAO inhibitors improve the symptoms of schizophrenia and depression, they can increase the plasma levels but not brain levels of D-serine. The mechanism of action of DAAO inhibitors remains unclear. We investigated the effects of the DAAO inhibitor sodium benzoate on the prefrontal cortex and hippocampal level of D-alanine as known another substrate with antipsychotic and antidepressant properties and other NMDAR-related amino acids, such as, L-alanine, D-serine, L-serine, D-glutamate, L-glutamate, and glycine levels. Our results indicate that sodium benzoate exerts antipsychotic and antidepressant-like effects without changing the D-serine levels in the brain prefrontal cortex (PFC) and hippocampus. Moreover, D-alanine levels in the PFC and hippocampus did not change. Despite these negative findings regarding the effects of D-amino acids in the PFC and hippocampus, sodium benzoate exhibited antipsychotic and antidepressant-like effects. Thus, the therapeutic effects of sodium benzoate are independent of D-serine or D-alanine levels. In conclusion, sodium benzoate may be effective among patients with schizophrenia or depression; however, the mechanisms of actions remain to be elucidated.

A novel l-rhamnose-binding lectin participates in defending against bacterial infection in zebrafish.

l-rhamnose-binding lectin (RBL), which is a class of animal lectins independent of Ca2+, can specifically bind l-rhamnose or d-galactose. Although several lectins in zebrafish have been reported, their functional mechanisms have not been fully uncovered. In this study, we discovered a novel l-rhamnose binding lectin (DrRBL) and studied its innate immune function. The DrRBL protein contains only one carbohydrate-recognition domain (CRD), which includes two strictly conserved motifs, "YGR" and "DPC". DrRBL was detected in all tested tissues and was present at high levels in the spleen, hepatopancreas and skin. After Aeromonas hydrophila challenge, the DrRBL mRNA level was significantly upregulated. Additionally, DrRBL was secreted into the extracellular matrix. Recombinant DrRBL (rDrRBL) could significantly inhibit the growth of gram-positive/negative bacteria, bind to several bacteria and cause obvious agglutination. The rDrRBL protein could combine with polysaccharides, such as PGN and LPS, rather than LTA. A more detailed study showed that rDrRBL could combine with monosaccharides, such as mannose, rhamnose and glucose, which are important components of PGN and LPS. However, rDrRBL could not bind to ribitol, which is an important component of LTA. The DrRBL deletion mutants, DrRBLΔ144-150 and DrRBLΔ198-200, were also constructed. DrRBLΔ144-150 ("ANYGRTD" deficient) showed weak bacterial inhibiting ability. However, DrRBLΔ198-200 ("DPC" deficient) showed weak agglutination ability. These results suggest that the "DPC" domain is important for agglutination. The conserved domain "ANYGRTD" is essential for inhibiting bacterial growth.

A C-type lectin containing two carbohydrate recognition domains participates in the antibacterial response by regulating the JNK pathway and promoting phagocytosis.

C-type lectins (CTLs) are important immune-related molecules in crustaceans. However, the immunologic mechanism by which CTLs eliminate invading pathogens is still unclear. In this study, we studied the antimicrobial mechanism of a CTL containing two carbohydrate recognition domains (DClec). After Aeromonas hydrophila challenge, several antimicrobial peptides (ALF1, ALF4, ALF5 and lys-i2) were upregulated. The transcript levels of ALF1, ALF4 and ALF5 were downregulated after A. hydrophila challenge in groups with DClec interference or inhibition compared with the control group. Similar results were obtained after c-Jun N-terminal kinase (JNK) interference. This finding indicates that DClec might regulate the JNK signalling pathway and subsequently adjust antimicrobial peptide (AMP) expression. Additionally, we found that DClec was secreted into the hemolymph. Recombinant protein DClec (rDClec) agglutinated gram-positive or gram-negative bacteria. Both rDClec and the native DClec in hemolymph bound to different bacteria. In this process, Ca2+ promoted the rDClec bacterial binding ability. After DClec interference, the phagocytosis ability of hemocytes was lower than that of the control group. Therefore, DClec can facilitate bacterial elimination by promoting AMPs expression and hemocyte phagocytosis.

Omega-3 polyunsaturated fatty acids in cardiovascular diseases comorbid major depressive disorder - Results from a randomized controlled trial.

INTRODUCTION: Cardiovascular diseases (CVDs) and major depressive disorder (MDD) will be the two most disabling diseases by 2030. Patients with CVDs comorbid depression had lower levels of total omega-3 polyunsaturated fatty acids (n-3 PUFAs), docosahexaenoic acid (DHA), and a higher omega-6 to omega-3 ratio. However, there have been limited studies on the effects n-3 PUFAs on MDD in patients with CVDs. METHOD: We have enrolled a total of 59 patients (64% males, mean age of 61.5 ±â€¯9.0 years and mean education of 10.2 ±â€¯4.2 years) with CVDs comorbid MDD. They were randomized into either receiving n-3 PUFAs (2 g per day of eicosapentaenoic acid (EPA) and 1 g of DHA) or placebo for 12 weeks. We assessed depression symptom severity with Hamilton Depression Rating Scale (HAMD) and Beck Depression Inventory (BDI), as well as blood fatty acid levels, electrocardiogram and blood biochemistry, at the baseline and at the endpoint. RESULTS: There were no differences between the n-3 PUFAs and placebo group in the changes of HAMD and BDI total scores, while PUFAs group had a greater reduction in HAMD Cognition subscale scores than the placebo group at week 8 (p < 0.05). Moreover, subgroup analyses found that the n-3 group had a greater reduction of HAMD Core subscale scores than the placebo group at the end of week 12 (p < 0.05) for the very severe DEP group (HAMD ≥ 23). CONCLUSION: Overall, n-3 PUFAs did not show a beneficial effect on depressive symptoms when compared with placebo. However, when stratified with depression severity, n-3 PUFAs supplementation improved core depression symptoms in the very severe MDD group. N-3 PUFAs supplementation may provide a treatment option for a subpopulation of patients with CVDs comorbid MDD.

Thymosin participates in antimicrobial immunity in zebrafish.

Thymosin hormones, which were shown to be involved in immune system development and differentiation in previous studies, have antimicrobial functions in different animals. Zebrafish are a useful model for immunology research. Although thymosin has been reported to be involved in the embryonic development of zebrafish, it is necessary to uncover the antimicrobial function of thymosin in zebrafish. In this study, we expressed thymosin ß (Tß) in zebrafish in vitro and studied its antimicrobial function. The Tß protein consists of 45 amino acids and is conserved among its family members, especially the actin-binding motif (LKKTET). Tß was expressed in all tested tissues and was highly expressed in the brain, liver and hindgut. After Aeromonas hydrophila challenge, the Tß transcript level increased in the skin, liver, kidney, spleen, thymus, foregut, gills and midgut. Purified recombinant thymosin ß (rTß) protein was used to study the antimicrobial mechanism. rTß could inhibit the growth of Staphylococcus aureus, Aeromonas hydrophila, Vibrio anguillarum, Pseudomonas aeruginosa and Klebsiella pneumoniae. rTß also binds to and agglutinates certain bacteria. Further study showed that rTß could combine with the polysaccharides from gram-negative and gram-positive bacterial walls. All results suggested that the Tß of zebrafish plays a significant role in innate antibacterial immune responses.

Is frying oil a dietary source of an endocrine disruptor? Anti-estrogenic effects of polar compounds from frying oil in rats.

The objective was to investigate endocrine-disrupting effects of polar compounds from oxidized frying oil. Estrogenicity of polar compounds was tested with a rat uterotrophic bioassay. Dietary oxidized frying oil (containing 51% polar compounds) or polar compounds isolated from it were incorporated into feed (in lieu of fresh soybean oil) and fed to ovariectomized rats, with or without treatment with exogenous ethynyl estradiol. Exogenous estrogen restored uterine weight, and caused histological abnormalities (stratified epithelia and conglomerate glands) as well as proliferation of uterine epithelial cells. However, tamoxifen or polar compounds reduced these effects. Furthermore, tamoxifen or polar compounds down-regulated uterine mRNA expression of estrogen receptor (ER)-target genes, implicating reduced ER activity in this hypo-uterotrophic effect. Inhibition of ER signaling and mitosis by polar compounds were attributed to reduced MAPK and AKT activation, as well as a reduced ligand binding domain-transactivity of ERα/ß. We concluded polar compounds from frying oil are potential endocrine-disrupting chemicals, with implications for food and environmental safety.

Scavenger Receptor C Mediates Phagocytosis of White Spot Syndrome Virus and Restricts Virus Proliferation in Shrimp.

Scavenger receptors are an important class of pattern recognition receptors that play several important roles in host defense against pathogens. The class C scavenger receptors (SRCs) have only been identified in a few invertebrates, and their role in the immune response against viruses is seldom studied. In this study, we firstly identified an SRC from kuruma shrimp, Marsupenaeus japonicus, designated MjSRC, which was significantly upregulated after white spot syndrome virus (WSSV) challenge at the mRNA and protein levels in hemocytes. The quantity of WSSV increased in shrimp after knockdown of MjSRC, compared with the controls. Furthermore, overexpression of MjSRC led to enhanced WSSV elimination via phagocytosis by hemocytes. Pull-down and co-immunoprecipitation assays demonstrated the interaction between MjSRC and the WSSV envelope protein. Electron microscopy observation indicated that the colloidal gold-labeled extracellular domain of MjSRC was located on the outer surface of WSSV. MjSRC formed a trimer and was internalized into the cytoplasm after WSSV challenge, and the internalization was strongly inhibited after knockdown of Mjß-arrestin2. Further studies found that Mjß-arrestin2 interacted with the intracellular domain of MjSRC and induced the internalization of WSSV in a clathrin-dependent manner. WSSV were co-localized with lysosomes in hemocytes and the WSSV quantity in shrimp increased after injection of lysosome inhibitor, chloroquine. Collectively, this study demonstrated that MjSRC recognized WSSV via its extracellular domain and invoked hemocyte phagocytosis to restrict WSSV systemic infection. This is the first study to report an SRC as a pattern recognition receptor promoting phagocytosis of a virus.

[Care Plan for Resuming the Physical Activity of Patients With Pancreatic Cancer and Diabetes After Surgery].

Many barriers influence the ability of postoperative cancer patients to reengage in normal physical activities. Training programs have been shown to be effective in helping restore physical activity in patients and in reducing the care burdens of family members. Nurses cannot use physical activity guidelines in their care plan to assess individual needs. The clinical practice guidelines for physical activity in survivorship were published by the National Comprehensive Cancer Network (NCCN) in 2016. These guidelines are used to assess patients' physical status, curable factors, physical barriers, and risk of postoperative pancreatic cancer and diabetes. In line with this assessment tool, the physical activity guidelines, and the recommendations for cancer patients, the authors planned a physical activity training program that addressed the actual needs of patients under their care. Further, the authors provided special notes for a diabetic diet that helped reduce the barriers to resuming physical activity and enhanced independent care efficacy. Meanwhile, the authors encouraged family members to participate in patient-care activities and family mental-health support and to promote patient participation in the training program in order to increase quality of life. The present project demonstrates that this care plan may provide an effective guide for nurses to help other cancer patients resume physical activity.

The bHLH142 Transcription Factor Coordinates with TDR1 to Modulate the Expression of EAT1 and Regulate Pollen Development in Rice.

Male sterility plays an important role in F1 hybrid seed production. We identified a male-sterile rice (Oryza sativa) mutant with impaired pollen development and a single T-DNA insertion in the transcription factor gene bHLH142. Knockout mutants of bHLH142 exhibited retarded meiosis and defects in tapetal programmed cell death. RT-PCR and in situ hybridization analyses showed that bHLH142 is specifically expressed in the anther, in the tapetum, and in meiocytes during early meiosis. Three basic helix-loop-helix transcription factors, UDT1 (bHLH164), TDR1 (bHLH5), and EAT1/DTD1 (bHLH141) are known to function in rice pollen development. bHLH142 acts downstream of UDT1 and GAMYB but upstream of TDR1 and EAT1 in pollen development. In vivo and in vitro assays demonstrated that bHLH142 and TDR1 proteins interact. Transient promoter assays demonstrated that regulation of the EAT1 promoter requires bHLH142 and TDR1. Consistent with these results, 3D protein structure modeling predicted that bHLH142 and TDR1 form a heterodimer to bind to the EAT1 promoter. EAT1 positively regulates the expression of AP37 and AP25, which induce tapetal programmed cell death. Thus, in this study, we identified bHLH142 as having a pivotal role in tapetal programmed cell death and pollen development.

Pathogen invasion changes the intestinal microbiota composition and induces innate immune responses in the zebrafish intestine.

Numerous bacteria are harbored in the animal digestive tract and are impacted by several factors. Intestinal microbiota homeostasis is critical for maintaining the health of an organism. However, how pathogen invasion affects the microbiota composition has not been fully clarified. The mechanisms for preventing invasion by pathogenic microorganisms are yet to be elucidated. Zebrafish is a useful model for developmental biology, and studies in this organism have gradually become focused on intestinal immunity. In this study, we analyzed the microbiota of normal cultivated and infected zebrafish intestines, the aquarium water and feed samples. We found that the predominant bacteria in the zebrafish intestine belonged to Gammaproteobacteria (67%) and that feed and environment merely influenced intestinal microbiota composition only partially. Intestinal microbiota changed after a pathogenic bacterial challenge. At the genus level, the abundance of some pathogenic intestinal bacteria increased, and these genera included Halomonas (50%), Pelagibacterium (3.6%), Aeromonas (2.6%), Nesterenkonia (1%), Chryseobacterium (3.4‰), Mesorhizobium (1.4‰), Vibrio (1‰), Mycoplasma (0.7‰) and Methylobacterium (0.6‰) in IAh group. However, the abundance of some beneficial intestinal bacteria decreased, and these genera included Nitratireductor (0.8‰), Enterococcus (0.8‰), Brevundimonas (0.7‰), Lactococcus (0.7‰) and Lactobacillus (0.4‰). Additionally, we investigated the innate immune responses after infection. ROS levels in intestine increased in the early stages after a challenge and recovered subsequently. The mRNA levels of antimicrobial peptide genes lectin, hepcidin and defensin1, were upregulated in the intestine after pathogen infection. These results suggested that the invasion of pathogen could change the intestinal microbiota composition and induce intestinal innate immune responses in zebrafish.

Scavenger receptor C promotes bacterial clearance in kuruma shrimp Marsupenaeus japonicus by enhancing hemocyte phagocytosis and AMP expression.

Scavenger receptors (SRs) comprise a large family of structurally diverse glycoproteins located on the cell membrane and function as pattern-recognition receptors (PRRs) participating in innate immunity in different species. Class C scavenger receptor (SRC) has been only identified in invertebrates and its biological functions still need to be researched. In this study, we characterized the anti-bacterial function of a SRC from kuruma shrimp Marsupenaeus japonicus (MjSRC). The mRNA level of MjSRC was up-regulated significantly in hemocytes of kuruma shrimp challenged by Vibrio anguillarum or Staphylococcus aureus. The recombinant extracellular domains (MAM and CCP domains) of MjSRC have the ability of binding different bacteria and glycans in vitro. After knockdown of MjSRC, the bacterial clearance ability and phagocytic rate of hemocyte decreased significantly in vivo. Meanwhile, overexpression of MjSRC in shrimp enhanced the clearance ability and phagocytic rate of hemocytes. Further study found that MjSRC could regulate the expression of several antimicrobial peptides (AMPs). All these results indicate that MjSRC plays important roles in antibacterial immunity in kuruma shrimp by enhancing hemocyte phagocytosis and AMP expression.

Polyunsaturated fatty acids levels and initial presentation of somatic symptoms induced by interferon-alpha therapy in patients with chronic hepatitis C viral infection.

OBJECTIVES: Somatic symptoms are common in depressive disorder and are similar to sickness behaviors due to inflammatory activation after cytokine administration. Omega-3 polyunsaturated fatty acids (PUFAs) are natural anti-inflammatory agents and may reduce inflammation-induced behavioral changes. The aim of this study was to investigate the role of PUFAs on the development of somatic symptoms and depression in patients of hepatitis C virus infection (HCV) receiving interferon-alpha therapy (IFN-α) in a prospective manner. METHODS: In this 24-week, prospective cohort study, 43 patients with chronic HCV ongoing IFN-α therapy were assessed with the mini-international neuropsychiatric interview for major depressive episodes and neurotoxicity rating scale (NRS) for somatic symptoms. RESULTS: One-third later developed IFN-α-induced depression (depression (DEP) group). As compared to subjects without depression, DEP group had higher NRS scores (P < 0.001), lower eicosapentaenoic acid (EPA) levels (P = 0.038) at week 2. Somatic symptoms, regardless of painful/non-painful characteristics, had positive association with arachidonic acid (P < 0.05), and negative association with EPA (P < 0.05). CONCLUSION: This study implies that early intervention with omega-3 PUFAs might be a promising strategy to prevent depression and somatic symptoms in patients receiving cytokine therapy.

Houttuynia cordata aqueous extract attenuated glycative and oxidative stress in heart and kidney of diabetic mice.

PURPOSE: The anti-glycative and anti-oxidative effects from Houttuynia cordata leaves aqueous extract (HCAE) in heart and kidney of diabetic mice were examined. METHODS: HCAE, at 1 or 2 %, was supplied in drinking water for 8 weeks. Plasma glucose and blood urea nitrogen (BUN) levels and creatine phosphokinase (CPK) activity were measured. The production of oxidative and inflammatory factors was determined. Activity and protein expression of associated enzymes or regulators were analyzed. RESULTS: HCAE intake at both doses lowered plasma glucose and BUN levels, and CPK activity and also restored creatinine clearance rate in diabetic mice. HCAE intake, only at 2 %, retained plasma insulin levels (P < 0.05). HCAE reduced reactive oxygen species, protein carbonyl, interleukin-6, tumor necrosis factor-alpha, N (ε) -(carboxymethyl)-lysine, pentosidine and fructose levels, and reserved glutathione content in heart and kidney of diabetic mice (P < 0.05). Diabetes enhanced aldose reductase (AR) activity and protein expression in heart and kidney (P < 0.05). HCAE intake at both doses decreased renal AR activity and protein expression, but only at 2 % lowered cardiac AR activity and protein expression (P < 0.05). Diabetes increased protein expression of RAGE, p47(phox) and gp91(phox), nuclear factor kappa-B (NF-κB) p50, NF-κB p65 and mitogen-activated protein kinase in heart and kidney (P < 0.05). HCAE intake only at 2 % limited RAGE expression, but at 1 and 2 % downregulated p47(phox), NF-κB p65 and p-p38 expression in these organs (P < 0.05). CONCLUSIONS: These findings suggest that Houttuynia cordata leaves aqueous extract could ameliorate cardiac and renal injury under diabetic condition.

Polyunsaturated fatty acids (PUFAs) levels in patients with cardiovascular diseases (CVDs) with and without depression.

BACKGROUND: Cardiovascular diseases (CVDs) are commonly comorbid with depression and vice versa. Polyunsaturated fatty acids (PUFAs) have been suggested to mediate in CVDs and depression in cross-sectional and observational studies. With the patients of CVDs, we investigated the role of depression on the effect of PUFAs. METHODS: Forty-four patients with CVDs were recruited and assessed with Hamilton depression rating scale (HAMD). Patients' CVDs markers were measured by electrocardiogram and their red blood cell (RBC) samples were collected for PUFAs analyses. RESULTS: The data of 44 subjects were analyzed; where 10 participants (23%) with CVDs had moderate or severe depression, defined by a HAMD score more than 19 points. The moderate depression group had lower docosahexaenoic acid (DHA), omega-3 (N3) and omega-6(N6) to N3 (N6/N3) ratio than non-depression group (HAMD score less than 8), while no differences between the 2 groups in terms of corrected QT (QTc) intervals and high sensitivity C-reactive protein (hsCRP) levels. Furthermore, when we analyzed the data with an inclusion of a more heterogeneous depression group, where HAMD score is greater than or equal to 10 (mild depression group, N=24), the differences in PUFAs levels between the 2 groups disappear. Secondary analysis of the moderate depression group showed a positive correlation between DHA, N3 PUFAs, and N6/N3 ratio and total HAMD scores, a positive correlation between N3 PUFAs and QTc intervals in non-depression group. CONCLUSION: Moderate depression group of patients with CVDs had lower levels of DHA, N3, and N6/N3 ratio than non-depression group, while both groups had no differences in QTc and hsCRP. On the other hand, the differences in PUFAs levels disappear in the mild depression group after inclusion of patients with CVDs with greater heterogeneity of depression. Hence, the role of N3 PUFAs is implicated in depression of patients with CVDs if the depression status is more strictly defined.

Catalase eliminates reactive oxygen species and influences the intestinal microbiota of shrimp.

Intestinal innate immune response is an important defense mechanism of animals and humans against external pathogens. The mechanism of microbiota homeostasis in host intestines has been well studied in mammals and Drosophila. The reactive oxygen species (ROS) and antimicrobial peptides have been reported to play important roles in homeostasis. However, how to maintain the microbiota homeostasis in crustacean intestine needs to be elucidated. In this study, we identified a novel catalase (MjCAT) involved in ROS elimination in kuruma shrimp, Marsupenaeus japonicus. MjCAT mRNA was widely distributed in hemocytes, heart, hepatopancreas, gills, stomach, and intestine. After the shrimp were challenged with pathogenic bacteria via oral infection, the expression level of MjCAT was upregulated, and the enzyme activity was increased in the intestine. ROS level was also increased in the intestine at early time after oral infection and recovered rapidly. When MjCAT was knocked down by RNA interference (RNAi), high ROS level maintained longer time, and the number of bacteria number was declined in the shrimp intestinal lumen than those in the control group, but the survival rate of the MjCAT-RNAi shrimp was declined. Further study demonstrated that the intestinal villi protruded from epithelial lining of the intestinal wall were damaged by the high ROS level in MjCAT-knockdown shrimp. These results suggested that MjCAT participated in the intestinal host-microbe homeostasis by regulating ROS level.

A fibrinogen-related protein (FREP) is involved in the antibacterial immunity of Marsupenaeus japonicus.

Fibrinogen-related proteins (FREPs) in invertebrates have important functions in innate immunity. In this study, the cDNA of FREP was identified from the kuruma shrimp Marsupenaeus japonicus (MjFREP2). The full-length cDNA of MjFREP2 is 1138 bp with an open reading frame of 954 bp that encodes a 317-amino acid protein comprising a signal peptide and a fibrinogen-like domain. MjFREP2 could be detected in hemocytes, heart, hepatopancreas, gills, stomach, and intestines. MjFREP2 could also be upregulated in hemocytes after Vibrio anguillarum and Staphylococcus aureus challenge. Agglutination and binding assay results revealed that the recombinant MjFREP2 bound to bacteria and polysaccharides. Immunocytochemical analysis results showed that MjFREP2 proteins were mainly distributed in the cytoplasm of hemocytes from unchallenged shrimp and transported to the membrane or secreted out of the cell after V. anguillarum or S. aureus challenge. The secreted MjFREP2 bound to the bacteria presented in shrimp hemolymph. The overexpression of MjFREP2 could enhance bacterial clearance by inducing the phagocytosis of hemocytes. This ability was impaired by knockdown of MjFREP2 with RNA interference. The cumulative mortality of MjFREP2-silenced shrimp was significantly higher than that of the control shrimp. These results suggested that MjFREP2 has an important function in the antibacterial immunity of M. japonicus.

Effect of Pleurotus tuber-regium polysaccharides supplementation on the progression of diabetes complications in obese-diabetic rats.

In this study, the effect of mushroom extracellular polysaccharides on fatty acid composition and liver peroxisome proliferator-activated receptor-alpha (PPAR-α) expression in obese-diabetic rats was investigated, and distinguished the association among anti-obesity, hypoglycemic and hypolipidemic properties. Extracellular polysaccharides from three different strains of Pleurotus tuber-regium were extracted and labeled as HP (high-percentage), MP (medium-percentage) and LP (low-percentage). Obese- diabetes (OD) was induced by chronic high-fat diet plus streptozotocin (STZ) injections. Simultaneously to the diet, polysaccharides were orally administered to OD groups (20 mg/kg body weight/8-week), and categorized into OD+HP, OD+MP and OD+LP groups (n = 10/group), respectively. High-fat diet plus STZ-induced hyperglycemia was prominently attenuated by polysaccharides. Increased fatty acid component n-6/n-3 ratio in liver and plasma of obese-diabetic rats was attenuated, while, reduced MUFA/ PUFA and MUFA/SFA ratios were restored (P < 0.01) with polysaccharides treatment. Furthermore, elevated serum total cholesterol, triglycerides and low-density lipoprotein (LDL) concentrations were controlled, and parallel restoration of decreased high-density lipoprotein (HDL) levels were found with polysaccharides supplementation. This hypolipidemic property might be associated with up-regulated liver PPAR-α mRNA expression and protein levels (P < 0.01). These findings concluded that stable fatty acid components and activated PPAR-α by polysaccharides may contribute to its hypoglycemic and hypolipidemic properties. Therefore, P. tuber-regium could be considered as nutritional supplement to treat diabetic complications.