Lipase Activity Research Articles

Insecticidal, biochemical and histological effects of monoterpenes against Musca domestica (Diptera: Muscidae)

The insecticidal activity of ten monoterpenes against larvae of Musca domestica (Diptera: Muscidae) was evaluated. Monoterpenes were mixed with food-media at concentrations of 2.5, 5.0, 10.0, 25.0, 50.0, 75.0 and 100.0 mg/kg. Three monoterpenes, p-cymene, 1,8-cineole and cuminaldehyde displayed a durable larvicidal activity with LC50 values of 0.14, 1.59 and 1.90 mg/kg 3 days post treatment. The three monoterpenes were more toxic than deltamethrin (LC50 = 3.36 mg/kg). Likewise, monoterpenes induced a significant reduction in pupation and adult emergence. Cuminaldehyde at 25.0 mg/kg, and p-cymene, 1,8-cineole and citronellal at 50.0 mg/kg caused a complete inhibition of pupation and adult emergence. Also, p-cymene at 25.0 mg/kg reduced the activity of larval amylase and lipase, while 1,8-cineole and cuminaldehyde increased their activity. Cuminaldehyde and α-terpinene inhibited the activity of proteases whereas p-cymene enhanced their activity. In the case of acetylcholinesterase, general-esterase and adenosinetriphosphatase, p-cymene and 1,8-cineole induced enzyme inhibition and citronellal increased enzyme activities. Finally, the tested monoterpenes caused histological changes on treated larvae, such as the basement membrane appeared and the epithelium cells deformed in some points and seen filled with scattered vacuoles. These findings indicate that the tested monoterpenes have a potential to be applied in IPM programs of M. domestica.

Formulation of Novel Microbial Consortia for Rapid Composting of Biodegradable Municipal Solid Waste: An Approach in the Circular Economy

Urbanization and rapid industrialization have led to the escalation of municipal solid waste generation and accumulation. Composting is widely recognized as a sustainable solution for solid waste management. However, its long-term investment is considered a disadvantage. The present research study discusses the rapid biotransformation of solid waste into valorized compost. Bacteria were isolated from soil, solid waste, and leachate samples from open dump sites. From the 18 different bacterial consortia created using potential isolates, the five most promising consortia were selected based on concurrent different enzyme production. These selected consortia were incorporated into typical compost bins with Municipal Solid Waste (MSW). Daily monitoring of enzymatic activity, pH, conductivity, bulk density, moisture, and temperature, along with other composting parameters, was conducted. The study’s results demonstrated that consortium No. 5, comprising Bacillus haynesii, Bacillus amyloliquefaciens, and Bacillus safensis, exhibited significant (p<0.05) enzyme activity of cellulase, amylase, lipase and proteinase enzymes during composting compared to the control and other treatment setups. Consortium No. 5 also facilitated rapid and successful composting, as evidenced by significant alterations of composting parameters by exhibiting a shorter average composting time, reducing it from 110±10 days to 20±3 days, showcasing the potential applicability of formulated bacterial consortium as a sustainable and greener approach to the global solid waste problem. The novelty of this study lies in the isolation of local bacterial strains from open dump sites soil, MSW, and MSW leachate samples, which were then utilized in the composting organic fraction of MSW, enhancing the potential for effective waste management.

Influence of Milk Pasteurization on the Key Aroma Compounds in a 30 Weeks Ripened Pilot-Scale Gouda Cheese Elucidated by the Sensomics Approach.

Gouda cheese was produced from pasteurized milk and ripened for 30 weeks (PM-G). By application of gas chromatography/olfactometry and an aroma extract dilution analysis on the volatiles isolated by extraction/SAFE distillation, 25 odor-active compounds in the flavor dilution (FD) factor range from 16 to 4096 were identified. Butanoic acid, 2- and 3-methylbutanoic acid, and acetic acid showed the highest FD factors, and 2-phenylethanol, δ-decalactone, and δ-dodecalactone were most odor-active in the neutral-basic fraction. Quantitations by stable isotope dilution assays followed by a calculation of odor activity values (OAVs) revealed acetic acid, 3-methylbutanoic acid, butanoic acid, and butane-2,3-dione with the highest OAVs. Finally, an aroma recombinate prepared based on the quantitative data well agreed with the aroma profile of the PM-G. In Gouda cheese produced from raw (nonpasteurized) milk (RM-G), qualitatively the same set of odor-active compounds was identified. However, higher OAVs of butanoic acid, hexanoic acid, and their corresponding ethyl esters were found. On the other hand, in the PM-G, higher OAVs for 3-methylbutanoic acid, 3-methylbutanol, 3-methylbutanal, and butane-2,3-dione were determined. The different rankings of these key aroma compounds clearly reflect the aroma differences of the two Gouda-type cheeses. A higher activity of lipase in the RM-G and higher amounts of free l-leucine in PM-G on the other side were responsible for the differences in the concentrations of some key aroma compounds.

Influence of Herba Houttuyniae added to fodder on the morphological structure of the intestinal tract, the digestive enzymes, the intestinal flora, and immune function of koi carp (Cyprinus carpio) infected with Aeromonas veronii.

This study investigated whether adding Herba Houttuyniae to feed can improve intestinal function and prevent diseases for koi carp (Cyprinus carpio) infected with Aeromonas veronii. There was a total of 168 koi carp with an average body length of (9.43 ± 0.99) cm and an average body weight of (26.00 ± 11.40) g. The K group was the control group fed with basal feed, while the C group was fed with feed with a H. houttuyniae content of six per thousand. After 14days of feeding, the fish were fasted for a day and then intraperitoneally injected with A. veronii for artificial infection, injection dose is 0.2mL, and the concentration is 1 × 107CFU/mL. Samples were collected from the two groups on days 0, 1, 2, and 4. The fold height, intestinal villus width, and muscle layer thickness in the gut of the koi carp were measured. In addition, on day 4, the activities of trypsin, α-amylase, and lipase in the gut were determined, and the intestinal flora of the carp in both groups was tested. The results showed that on the second and fourth days of sampling, the fold height and muscle layer thickness in the C group were significantly higher than those in the K group (P < 0.05). The villus width in the C group was slightly higher than that in the K group, but the difference was not significant (P > 0.05). Microscopic observation revealed that the intestinal structure of the carp in the C4 (day 4 in C group) group was more intact than that in the K4 (day 4 in K group) group. Moreover, the activities of trypsin, α-amylase, and lipase in the foregut and midgut in the C4 group were higher than those in the K4 group (P < 0.05). The activities of trypsin and α-amylase in the hindgut in the C4 group were higher than those in the K4 group (P < 0.05). Furthermore, beneficial bacteria, especially those in the genus Cetobacterium, were more abundant in the intestinal tract of the carp in the C4 group compared to the K group. In addition, comparisons and tests of IL-4 and IL-10 in the intestines of the fish in both groups demonstrated that the H. houttuyniae added to feed enhanced the immune function of the fish intestines after bacterial attack. In conclusion, for koi carp infected with A.veronii, adding H. houttuyniae to their feed not only improves the activity of digestive enzymes and the morphological structure of the intestine but also optimizes the beneficial intestinal microbiota, thereby protecting the intestinal tract.

Mechanistic insight into the anti-alternaria activity of bimetallic zinc oxide and silver/zinc oxide nanoparticles

Alternaria alternata is an opportunistic phytopathogen that negatively impact the growth and production of a wide variety of host plants. In this study, we evaluated the antifungal potential of biogenic ZnO, and bimetallic silver and zinc oxide (Ag/ZnO) nanoparticles synthesized using seed extract of Abrus precatorious and characterized using different analytical tools. In vitro antifungal potentials of ZnO and Ag/ZnO nanoparticles were carried out using the food poison technique. Morphological and ultrastructure of the A. alternata treated with the nanoparticles were carried out using high resolution scanning and transmission electron microscopy (HRSEM and HRTEM). In addition, changes in polysaccharide production, chitin content and enzymatic (cellulase and lipase) activities of A. alternata were assayed. Double peak signifying a UVmax of 353.88 and 417.25 nm representing Ag and ZnO respectively was formed in the bimetallic nanoparticles. HRSEM and HRTEM results shows agglomerated nanoparticles with particle and crystallite size of 23.94 and 16.84 nm for ZnO nanoparticles, 35.12 and 28.99 nm for Ag/ZnO nanoparticles respectively. In vitro antifungal assay shows a significant concentration-dependent inhibition (p < 0.05) of A. alternata mycelia with highest percentage inhibition of 73.93 % (ZnO nanoparticles) and 68.26 % (Ag/ZnO nanoparticles) at 200 ppm. HRSEM and HRTEM micrographs of the treated A. alternata mycelia shows alteration of the cellular structure, clearance of the cytoplasmic organelles and localization of the nanoparticles within the cell. A. alternata treated with 200 ppm nanoparticles show a significant decrease (p < 0.05) in the polysaccharides and chitin contents, cellulase and lipase activities. The results suggests that ZnO and Ag/ZnO nanoparticles mode of action may be via alteration of the fungal cell wall through the inhibition of polysaccharides, chitin, cellulases and lipases synthesis. ZnO and Ag/ZnO nanoparticles may be a promising tool for the management and control of disease causing fungal phytopathogens.

Exploring the relationship between dietary rapeseed meal, condensed tannin and growth, nutrive metabolism in largemouth bass (Micropterus salmoides)

This study evaluated the effects of rapeseed meal (RM) and condensed tannin (CT) on the growth and nutritional metabolism of largemouth bass (Micropterus salmoides), and speculated whether there was interaction between anti-nutritional factors in RM. Eight diets were formulated for 55-day feeding trial, six of which were practical diet groups, including control group (CG), five RM inclusive groups with graded RM levels of 5% (RM5), 10% (RM10), 15% (RM15), 20% (RM20) and 25% (RM25) partially replacing fishmeal, and the other two were semi-purified diets with 0.062% CT (CT5) ≈ the CT content in the RM5 and 0.31% CT (CT25) ≈ the CT content in the RM25. The results of the experiments on replacing fishmeal with RM demonstrated that with the increase of RM substitution level, the weight gain rate (WGR), survival rate (SR) and specific growth rate (SGR) of largemouth bass showed a downward trend. High levels of RM led to the inhibition of digestive enzyme activity in largemouth bass, as well as the manifestation of abnormal markers related to protein, fat, and carbohydrate metabolism in both plasma and liver. RM reduced muscle protein and fat content, although the effect was not statistically significant at 5% RM level. The results of CT concentration experiments showed that the addition of 0.31% CT significantly reduced WGR, SGR, SR, protein efficiency ratio (PER) and gastrointestinal digestive enzyme activity, and significantly increased the feed coefficient ratio (FCR), plasma ammonia (PA), plasma glucose (PG), and hepatic glycogen (HG) and liver triglyceride (TG). The addition of 0.062% CT significantly reduced PG and HG. Supplementation of CT significantly reduced muscle fat. Among the groups of CT supplementation and RM, CT5 exhibited superior WGR, PER and FCR compared to RM5, along with enhanced intestinal trypsin, amylase activity, liver glutamic pyruvic transaminase (GPT) activity and decreased content of HG and liver TG; CT25 exhibited decreased activities of gastric lipase (LPS), enteric trypsin and pepsin, and increased content of total cholesterol (T-CHO) and glucose in plasma in compariosn to RM25, accompanied with no significant change in growth performance. Therefore, largemouth bass exhibited tolerance to a 5% inclusion of RM in the feed without compromising their growth, digestion and metabolic functions. The incorporation of 5% RM, equivalent to a supplemental 0.062% CT, had regulatory effects on the digestion and metabolism of largemouth bass while improving feed utilization. There was an interaction among anti-nutritional factors in RM, with synergistic effect being evident at low RM levels, whereas antagonism more promient at high levels of RM.

WITHDRAWN: Catalytic activity of Candida rugosa lipase immobilized on lignocellulosic wastes: Effect of support material

WITHDRAWN: Catalytic activity of Candida rugosa lipase immobilized on lignocellulosic wastes: Effect of support material

Effects of swimming activity and feed restriction on antioxidant and digestive enzymes in juvenile rainbow trout: Implications for nutritional and exercise strategies in aquaculture.

In this study, we investigated the effects of swimming activity and feed restriction on digestion and antioxidant enzyme activities in juvenile rainbow trout (average body weight of 26.54±0.36g). The stomach, liver and kidney tissues were obtained from four distinct groups: the static water group (fish were kept in static water and fed to satiation), the feeding restricted group (fish were kept in static water with a 25% feed restriction), the swimming exercised group (fish were forced to swimming at a flow rate of 1 Body Length per second (BL/s)) and the swimming exercised-feed restricted group (subjected to swimming exercise at a 1BL/s flow rate along with a 25% feed restriction). We determined the levels of glutathione, lipid peroxidation and the activities of catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase and lactate dehydrogenase, as well as the presence of reactive oxygen species in the tissues obtained from the fish. Additionally, the activities of pepsin, protease, lipase and arginase in these tissues were measured. Swimming activity and feed restriction showed different effects on the enzyme activities of the fish in the experimental groups. It can be concluded that proper nutrition and exercise positively influence the antioxidant system and enzyme activities in fish, reducing the formation of free radicals. This situation is likely to contribute to the fish's development.

Diet Shifts Alter the Activity and Distribution of Digestive Enzymes in an Herbivorous Fish

The digestive tract is central to the function of an animal since it assimilates nutrients from the diet. Digestion itself is a chemical process and digestive enzymes are the digestive catalysts. Thus, we measured amylase, maltase, N-acetyl-b-d-glucosaminidase, lipase, trypsin, aminopeptidase, and alkaline phosphatase activities along the digestive tract of the marine herbivorous fish, Cebidichthys violaceus. We did this for wild-caught individuals of this species, and compared those to individuals fed carnivore, omnivore, and herbivore diets in the laboratory for six months. In laboratory fish, the enzymatic activities were generally lower compared to wild-caught fish. In wild caught fish, a strong anterior-to-posterior gradient of amylase activity was observed along the gut and this pattern largely disappeared in the lab-fed fish. N-acetyl-β-D-glucosaminidase (NAGase), which breaks down chitin products, showed an increase in activity in the distal intestines of the lab-fed fish, which is not observed in wild fish. The NAGase activity of the herbivorous fishes correlate with the bacterial species Paroccus sp., which is a known NAGase producer, and one of the dominant microbes in the distal intestines of the lab-fed fish. The role of this enzyme, however, remains unclear since the lab diets did not contain large amounts of chitin. These enzymatic differences tell us how much fish can modify their enzymatic activity to align with their diet. In summary, the findings show that C. violaceous can endure different degrees of protein and carbohydrate levels, within limits. Their digestive system clearly changed in response to more protein in the diet, along with a microbiome that had more potential pathogens. Live algal diets would may be the most suitable for this herbivorous fish based on the totality of gathered data from the lab. American Physiological Society Fellowship UCI Microbiome Initiative Grant. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Insight into the spoilage heterogeneity of meat-borne bacteria isolates with high-producing collagenase

Chilled chicken is inevitably contaminated by microorganisms during slaughtering and processing, resulting in spoilage. Cutting parts of chilled chicken, especially wings, feet, and other skin-on products, are abundant in collagen, which may be the primary target for degradation by spoilage microorganisms. In this work, a total of 17 isolates of spoilage bacteria that could secrete both collagenase and lipase were determined by raw-chicken juice agar (RJA) method, and the results showed that 7 strains of Serratia, Aeromonas, and Pseudomonas could significantly decompose the collagen ingredients. The gelatin zymography showed that Serratia liquefaciens (F5) and Pseudomonas saponiphila (G7) had apparent degradation bands around 50 kDa, and Aeromonas veronii (G8) and Aeromonas salmonicida (H8) had a band around 65 and 95 kDa, respectively. The lipase and collagenase activities were detected isolate-by-isolate, with F5 showing the highest collagenase activity. For spoilage ability on meat in situ, F5 performed strongest in spoilage ability, indicated by the total viable counts, total volatile basic nitrogen content, sensory scores, lipase, and collagenase activity. This study provides a theoretical basis for spoilage heterogeneity of strains with high-producing collagenase in meat.

Formation of lipid-derived volatile products through lipoxygenase (LOX)- and hydroperoxide lyase (HPL)- mediated pathway in oat, barley and soy bean

The aim of this study was to explore the formation of volatile lipid oxidation products by the lipoxygenase (LOX)-hydroperoxide lyase (HPL)-mediated pathway in oat, barley and soy bean. LOX activity was found only in barley and soy bean samples, but the lipase and HPL activity was detected in all samples. HPL showed particularly high activity with 13-hydroperoxides, while the activity was quite low when using 9-hydroperoxides, especially in the oat and barley. The optimum pH for HPL in different samples was similar, i.e., pH 6–7. In this condition, the volatile compounds formed dramatically with aldehydes and furans as the dominant products. Furthermore, a remarkable enzymatic degradation of lipids occurred during the preparation of food models with highly refined rapeseed oil (RO) and rapeseed oil fatty acid (ROFA) emulsions, where the ROFAs were more prone to oxidation than RO. This study shows the significance of lipid-degrading enzymes in plant-food flavour formation.

Abstract 1061: The Phospholipase cγ2 And Protein Kinase cα Signaling Axis Is A Key Regulator Of The Extracellular Digestion Of Lipoprotein Aggregates By Macrophages

Atherosclerosis is characterized by cholesterol ester accumulation in macrophages, leading to foam cell formation. In atherosclerotic lesions, most lipoproteins are aggregates (agLDL) that are tightly crosslinked to the extracellular matrix, making digesting them by endocytosis or phagocytosis difficult. Thus, it has been unclear how the cholesteryl esters in the core of agLDL are hydrolyzed. Our laboratory discovered a novel mechanism macrophages use to digest agLDL and generate free cholesterol in an extracellular, acidic, hydrolytic compartment known as the lysosomal synapse. Macrophages form a tight seal around agLDL through actin polymerization and deliver lysosomal contents into this space in a process termed digestive exophagy. Vacuolar ATPase on the plasma membrane lowers the pH of the lysosomal synapse, enabling lysosomal acid lipase (LAL) activity. LAL generates free cholesterol, which accumulates in macrophages and leads to foam cell formation. Our laboratory has begun to characterize the signaling pathways that regulate digestive exophagy, having previously identified TLR4 activation of MyD88/Syk as critical. Here, our goal was to identify digestive exophagy regulators downstream of Syk. Syk activates Bruton’s tyrosine kinase (BTK) and phospholipase Cγ2 (PLCγ2). We tested the hypothesis that Syk phosphorylates and activates PLCγ2 during digestive exophagy. Using pharmacological treatment and genetic manipulation, we found that PLCγ2 and to a lesser extent BTK regulate digestive exophagy. We confirmed that inhibition of Syk or BTK leads to a loss of PLCγ2 activation. PLCγ2 cleaves PI(4,5)P 2 into diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP 3 ). Soluble IP 3 then activates the release of Ca 2+ from the endoplasmic reticulum (ER) into the cytoplasm. We demonstrated that Ca 2+ release from the ER is upregulated by agLDL and plays a role in digestive exophagy. Both DAG and Ca 2+ activate protein kinase Cα (PKCα). We also found that PKCα regulates digestive exophagy. In conclusion, we identified new signaling mechanisms regulating digestive exophagy downstream of Syk. We hope that expanding our understanding of the mechanisms of digestive exophagy will be helpful in identifying therapeutics to slow atherosclerosis.

Lipase and Protease Production Ability of Multi-drug Resistant Bacteria Worsens the Outcomes of Wound Infections.

Surgical site infections are one of the major clinical problems in surgical departments that cost hundreds of millions of dollars to healthcare systems around the world. The study aimed to address the pressing issue of surgical site infections, which pose significant clinical and financial burdens on healthcare systems globally. Recognizing the substantial costs incurred due to these infections, the research has focused on understanding the role of lipase and protease production by multi-drug resistant bacteria isolated from surgical wounds in the development of post-surgical wound infections. For these purposes, 153 pus specimens were collected from patients with severe post-surgical wound infections having prolonged hospital stays. The specimens were inoculated on appropriate culture media. Gram staining and biochemical tests were used for the identification of bacterial growth on suitable culture media after 24 hours of incubation. The isolated pathogens were then applied for lipase and protease, key enzymes that could contribute to wound development, on tributyrin and skimmed milk agar, respectively. Following the CSLI guidelines, the Kirby-Bauer disc diffusion method was used to assess antibiotic susceptibility patterns. The results revealed that a significant proportion of the samples (127 out of 153) showed bacterial growth of Gram-negative (n = 66) and Gram-positive (n = 61) bacteria. In total, isolated 37 subjects were declared MDR due to their resistance to three or more than three antimicrobial agents. The most prevalent bacteria were Staphylococcus aureus (29.13%), followed by S. epidermidis (18.89%), Klebsiella pneumoniae (18.89%), Escherichia coli (14.96%), Pseudomonas aeruginosa (10.23%), and Proteus mirabilis (7.87%). Moreover, a considerable number of these bacteria exhibited lipase and protease activity with 70 bacterial strains as lipase positive on tributyrin agar, whereas 74 bacteria showed protease activity on skimmed milk agar with P. aeruginosa as the highest lipase (69.23%) and protease (76.92%) producer, followed by S. aureus (lipase 62.16% and protease 70.27%). The antimicrobial resistance was evaluated among enzyme producers and non-producers and it was found that the lipase and protease-producing bacteria revealed higher resistance to selected antibiotics than non-producers. Notably, fosfomycin and carbapenem were identified as effective antibiotics against the isolated bacterial strains. However, gram-positive bacteria displayed high resistance to lincomycin and clindamycin, while gram-negative bacteria were more resistant to cefuroxime and gentamicin. In conclusion, the findings suggest that lipases and proteases produced by bacteria could contribute to drug resistance and act as virulence factors in the development of surgical site infections. Understanding the role of these enzymes may inform strategies for preventing and managing post-surgical wound infections more effectively.

Relationships between Body Composition Measurements and Insulin-Stimulated Plasma Lipoprotein Lipase Activity in Individuals with Varying Degrees of Body Adiposity

Lipoprotein Lipase (LPL) hydrolyzes plasma triglycerides into free fatty acids in the circulation for use and/or storage in tissues (i.e., adipose tissue, skeletal muscle). Impaired LPL activity (LPLa) is associated with unfavorable health outcomes, such as elevated plasma triglyceride concentrations. We sought to determine how plasma LPLa relates to body composition measurements in individuals with varying degrees of adiposity. Eighteen subjects (ages 19 to 45 years) with body mass index (BMI) between 18 and 45 kg/m2 had their body composition measured by dual-energy X-ray absorptiometry (DEXA) and insulin sensitivity estimated from an oral glucose tolerance test by using the Matsuda Index (MI). Subjects ingested a bolus of 5g fat (i.e., whipping cream, 0.2 g fat/kg fat free mass), followed by small boluses of fat over the course of a 3-hour experimental period. This experimental protocol allows for the induction of a postprandial state without perturbation of the plasma triglyceride or insulin concentrations. LPLa was measured in the presence of increased plasma insulin induced by intravenous insulin infusion during the last 30 mins of the 3-hour experimental protocol. Insulin was infused at a rate of 0.5 mU/kg/min for subjects with MI-determined insulin sensitivity &lt; 4 and 1 mU/kg/min for those with MI-determined insulin sensitivity &gt; 4, in order to produce comparable levels of plasma insulin concentrations across subjects. To release endothelial-bound LPL, subjects received an injection of intravenous heparin (75 UI/kg) at the end of the plasma insulin infusion. Plasma samples were collected 10 minutes after the heparin infusion and analyzed for LPL concentration (LPLc) and LPLa using commercially available ELISA kits. Person’s correlation was used to evaluate relationships between several body composition parameters and LPLc as well as LPLa. LPLc was not correlated (P &gt;0.05) with BMI (r = 0.03), total lean body mass (r = -0.20), total body fat (r = -0.02), or android fat (r = - 0.08). However, LPLa was positively correlated (P &lt;0.05) with BMI (r = 0.49) and total lean body mass (r = 0.58), as well as total body fat (r = 0.54, P = 0.02) and android fat (r = 0.58, P = 0.01). In conclusion, increased body fat, including android fat, are associated with increased intravascular LPLa in the presence of insulin. Greater insulin-stimulated intravascular LPLa can enhance the release of triglyceride-associated free fatty acids and their uptake by tissues, resulting in insulin resistance as documented in individuals with increased android fat distribution. American Diabetes Association Grant #7-12-CT-40. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

ANGPTL3 accelerates atherosclerotic progression via direct regulation of M1 macrophage activation in plaque

IntroductionThe N-terminal domain of angiopoietin-like protein 3 (ANGPTL3) inhibits lipoprotein lipase activity. Its C-terminal fibrinogen-like (FBN) domain is a ligand of macrophage integrin αvβ3. ObjectivesANGPTL3 might home to plaque where it directly regulates macrophage function via integrin αvβ3 for atherosclerosis progression. MethodsLdlr-/- mice on a high-fat diet and ApoE-/- mice on a chow diet were received adeno-associated virus (AAV)-mediated Angptl3 gene transfer and followed up for 12 weeks. ApoE-/- mice were injected AAV containing FLAG-tagged Angptl3 cDNA for tracing. Atherosclerotic features were compared between Angptl3-/-ApoE-/- mice and ApoE-/- littermates. THP-1 cells were exposed to 0 or 50 μg/ml ANGPTL3 FBN domain for 24 h to evaluate Toll-like receptor (TLR)4 expression using western blot analysis and circulating cytokine and chemokine profiles by the MILLIPLEX MAP assay. Phospho-proteomic profile was established in ANGPTL3-treated macrophages. Integrin β3 deficient THP-1 cells were obtained by sgRNAs targeting RGD sequence using Lentivirus-Cas9 system. ResultsAngptl3 overexpression increased atherosclerotic progression and CD68+ macrophages in plaque (p < 0.05 for all). By immunostaining, FLAG+ cells were identified in plaque of gene transferred ApoE-/- mice. Fluorescent immunostaining detected co-localisation of Angptl3 and CD68 in plaque macrophages. Phospho-proteomic analysis revealed that Angptl3 induced phosphorylation of proteins that were involved in the IL-17 signalling pathway in THP-1 cells. In vitro, ANGPTL3 treatment increased the production of interleukin (IL)-1β and tumour necrosis factor-α in THP-1 cells (p < 0.05 for both). Exposure of ANGPTL3 to THP-1 cells induced Akt phosphorylation which was weakened in integrin β3 deficient ones. ANGPTL3 elevated TLR4 expression via Akt phosphorylation. In response to lipopolysaccharide, nuclear factor-κB activity was 2.2-fold higher in THP-1 cells pre-treated with ANGPTL3 than in untreated cells (p < 0.05). ConclusionsTargeting ANGPTL3 could yield a dual benefit of lowering lipid levels in the blood and suppressing macrophage activation in plaque.

Effect of water temperature on the development of Portunus trituberculatus larvae in the off-season breeding mode (Decapoda, Portunidae)

Abstract To clarify the influence of different water temperatures on the development of Portunus trituberculatus (swimming crab) larvae during off-season (early autumn) breeding, a gradient of four rearing temperatures of 27, 29, 31 and 33°C was set up, and the effects of water temperature on larval development were systematically compared. The results showed that the moulting cycle (MC) from the zoea 1 (Z1)-zoea 2 (Z2) stage was not significantly affected by water temperature (), remaining at approximately 3 days. However, in the Z2-megalopa (M) stage, the MC in the 31°C group was consistently the shortest. The total developmental duration and total effective cumulative temperature during Z1-M in the 31°C group were the lowest at 9.97 days and 250 days · °C, respectively. According to the equation of water temperature and larval development rate, the development rate was the fastest when the water temperature was 31°C. As the water temperature increased, the survival rate (SR) of larvae at various stages gradually decreased. The SR of the 27°C group was consistently significantly higher than that of the 33°C group (), especially in the M stage, where the SR of the 33°C group was only 2%, which was significantly lower than that of the 27°C and 29°C groups (). Among the antioxidant indexes, both superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) were the lowest in the 29°C group at 315.75 U/mg protein and 0.36 mmol/g protein, respectively, and both were significantly lower than those in the 33°C group (). Catalase (CAT) and glutathione peroxidase (GSH-PX) were both the lowest in the 31°C group, and in this group the CAT was significantly lower than in the 33°C group, and GSH-PX was significantly lower than in the 27°C group (). For malondialdehyde (MDA) content, the four groups were basically maintained at about 2.5 nmol/mg protein, and there was no significant difference (). In terms of digestive enzyme activity, the activity of lipase (LPS) was basically maintained at 1.93 U/g protein. The other four digestive enzyme activity differences were mainly reflected in that the 31 and 33°C groups maintained relatively higher levels than the 27 and 29°C groups, especially the activities of α-amylase (AMS), and cellulase (CL) in the 33°C group, which were significantly higher than those in the 27 and 29°C groups (). Comprehensive indicators indicate that a water temperature between 29 and 31°C is the appropriate temperature for the development of the larvae of off-season breeding swimming crabs.

Dietary Bacillus velezensis T23 fermented products supplementation improves growth, hepatopancreas and intestine health of Litopenaeus vannamei

This study aimed to elucidate the effects of dietary fermented products of Bacillus velezensis T23 on the growth, immune response and gut microbiota in Pacific white shrimp (Litopenaeus vannamei). Shrimp were fed with diets containing fermentation products of B. velezensis T23 at levels of (0, 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5 g/kg) for 4 weeks, to assess the influence on shrimp growth. The results showed that 0.3 and 0.4 g/kg T23 supplementation improved shrimp growth and feed utilization. Based on these results we selected these three diets (Control, 0.3T23 and 0.4T23) to assess the effect on immune response and gut microbiota of shrimp. Compared with the control, the 0.3T23 and 0.4T23 groups enhanced lipase and α-amylase activities in the gut significantly. Moreover, the 0.4T23 group decreased TAG and MDA levels in hepatopancreas, ALT and AST levels of serum significantly (P < 0.05). In hepatopancreas, CAT and SOD activities were improved observably and the MDA content was reduced markedly in both T23 groups. The expressions of antimicrobial related genes, Cru and peroxinectin in the 0.3T23 group, and proPO and peroxinectin in the 0.4T23 group were up-regulated remarkably (P < 0.05). Moreover, hepatopancreas of shrimp fed with a diet amended with T23 showed a significant down-regulated expression of nf-kb and tnf-α genes, while expressions of tgf-β was considerably up-regulated. Furthermore, serum LPS and LBP contents were reduced markedly in T23 groups. Intestinal SOD and CAT were noteworthy higher in T23 groups (P < 0.05). In the intestine of shrimp fed on the diet enriched with T23 the expression of nf-κb and tnf-α exhibited markedly down-regulated, whereas hif1α was up-regulated (P < 0.05). Besides, in the intestine of shrimp grouped under T23, Cru and peroxinectin genes were markedly up-regulated (P < 0.05). Dietary 0.3 g/kg T23 also upregulated the ratio of Rhodobacteraceae to Vibrionaceae in the gut of the shrimp. Taken together, the inclusion of B. velezensis T23 in the diet of shrimp enhanced the growth and feed utilization, enhanced hepatopancreas and intestine health.

Dietary Lycium barbarum Polysaccharide Modulates Growth Performance, Antioxidant Capacity, and Lipid Metabolism in Common Carp (Cyprinus carpio) Fed with High-Fat Diet.

To investigate the ameliorative effects and mechanism of Lycium barbarum polysaccharide (LBP) on growth performance, oxidative stress, and lipid deposition in common carp (Cyprinus carpio) fed with high-fat diets, fish with an initial weight of 5.29 ± 0.12 g were divided into five experimental groups-including normal-fat diets, high-fat diets, and high-fat diets-supplemented with LBP (0.5, 1.0, and 2.0 g/kg) for 8 weeks. The results showed that high-fat diets resulted in significant decreases in final body weight, weight gain rate, and specific growth rate of fish, as well as causing a significant decrease in hepatic total antioxidant capacity, catalase, and glutathione peroxidase activities. These changes were accompanied by a significant decrease in lipase activity and ATP level and a significant increase in malondialdehyde content. The expression levels of lipid metabolism-related genes (acetyl coenzyme A carboxylase 1, stearoyl coenzyme A desaturase 1, fat synthase, peroxisome proliferator-activated receptor-γ, fructofuranose bisphosphatase, and glucose-6-phosphatase) were also markedly elevated by high-fat diets. Supplementation with 0.5-2.0 g/kg LBP in high-fat diets improved the reduced growth performance, increased hepatic total antioxidant enzymes, catalase, and glutathione peroxidase activities, and lowered malondialdehyde level in fish fed with high-fat diets. Additionally, dietary supplementation with LBP significantly downregulated hepatic gene expression levels of acetyl coenzyme A carboxylase 1, stearoyl coenzyme A desaturase 1, fat synthase, sterol regulatory element-binding protein 1, peroxisome proliferator-activated receptor-γ, fructofuranose bisphosphatase, and glucose-6-phosphatase. In conclusion, fish fed with high-fat diets demonstrated impaired growth performance, antioxidant capacity, and lipid metabolism, and dietary supplementation with 0.5-2.0 g/kg LBP ameliorated the impairments induced by high-fat diets.

Effects of Dietary Supplementation of Bile Acids on Growth, Glucose Metabolism, and Intestinal Health of Spotted Seabass (Lateolabrax maculatus).

An 8-week feeding trial was performed to investigate the effects of dietary bile acids on growth, glucose metabolism, and intestinal health in spotted seabass (Lateolabrax maculatus) reared at high temperatures (33 °C). The fish (20.09 ± 1.12 g) were fed diets supplemented with bile acids: 0 (Con), 400 (BA400), 800 (BA800), and 1200 (BA1200) mg/kg, respectively. The results showed that the growth was promoted in fish at the BA800 treatment compared with the control (p < 0.05). Increased enzyme activities and transcripts of gluconeogenesis in the liver were observed, whereas decreased enzyme activities and transcripts of glycolysis, as well as glycogen content, were shown in the BA800 treatment (p < 0.05). The transcripts of bile acid receptors fxr in the liver were up-regulated in the BA800 treatment (p < 0.05). A bile acid supplementation of 800 mg/kg improved the morphological structure in the intestine. Meanwhile, intestinal antioxidant physiology and activities of lipase and trypsin were enhanced in the BA800 treatment. The transcripts of genes and immunofluorescence intensity related to pro-inflammation cytokines (il-1β, il-8, and tnf-α) were inhibited, while those of genes related to anti-inflammation (il-10 and tgf-β) were induced in the BA800 treatment. Furthermore, transcripts of genes related to the NF-κB pathway in the intestine (nfκb, ikkα, ikkβ, and ikbα1) were down-regulated in the BA800 treatment. This study demonstrates that a dietary bile acid supplementation of 800 mg/kg could promote growth, improve glucose metabolism in the liver, and enhance intestinal health by increasing digestive enzyme activity and antioxidant capacity and inhibiting inflammatory response in L. maculatus.

Beneficial effects of the butanoic acid derivative tributyrin on the growth, immunity and intestinal health of large mouth bass (Micropterus salmoides)

Tributyrin (TB) is a novel butanoic acid derivative with potent bioactive functions. In this study, an eight-week feeding trial aimed to investigate the effects of dietary TB on the growth, immunity and intestinal health of large mouth bass (Micropterus salmoides). Five experimental diets containing 0, 0.5, 1.0, 1.5 or 2.0 g/kg tributyrin were formulated and were regarded as TB0 (control), TB0.5, TB1.0, TB1.5 and TB2.0, respectively. Quadruplicate groups (four tanks per group, 30 fish per tank) of juvenile M. salmoides (initial weight: 20.00 ± 1.00 g) were fed to apparent satiation two times daily. After the feeding trial,Aeromonas hydrophila challenge tests were conducted and the A. hydrophila strains were subsequently sampled. As a result, the weight gain rate (WGR) was increased in the TB supplementation groups, and the TB1.5 group obtained the highest value. Furthermore, TB administration improved immune function. The content of serum complement 4 in the TB1.5 group was significantly higher than that in the control group. Increase of lysozyme activity and immunoglobulin M were significant in TB1.0 group than the control group. After A. hydrophila injection, TB1.0, TB1.5 and TB2.0 groups presented markedly higher survival rates than did the control group. Additionally, TB markedly enhanced the activities of amylase and lipase in the gut. Moreover, 16S rRNA sequencing revealed that TB could affect the intestinal microflora composition. Compared to those in the control group, the abundance of Fusobacteria were lower in the TB1.0 and TB1.5 groups. In conclusion, this study demonstrated that TB can improve the growth, immunity and intestinal health of M. salmoides, and the optimal dietary level of TB is determined to be 0.15%.