Regulatory effects of Astragalus membranaceus polysaccharides on lipid metabolism disorders induced by a high-fat diet in spotted sea bass (Lateolabrax maculatus).

This study evaluated the regulatory effects of Astragalus membranaceus polysaccharides (AMP) on lipid metabolism disorders induced by a high-fat diet (HFD) in spotted sea bass (Lateolabrax maculatus). Compared with the normal diets (10 % lipids), diets containing 15 % lipid levels were used as the high-fat diet (HFD). Three levels of the AMP (0.06 %, 0.08 %, 0.10 %) were added in the HFD and used as experimental diets. A total of 375 spotted sea bass (average weight 3.00 ±â€¯0.01 g) were divided into 15 tanks and deemed as 5 groups, with each tank containing 25 fish. Fish in each group were fed with different diets for 56 days. After feeding, the HFD induced lipid metabolism disorders in fish, as evidenced by elevated serum lipids, malonaldehyde levels, and more severe liver damage. The AMP alleviated the HFD-induced liver damage, as evidenced by the reduced severity of liver histological lesions and malonaldehyde levels. The low-density lipoprotein cholesterol was reduced, and the expression of FAS and PPAR-α were down and up-regulated, respectively. However, the AMP had a limited ability to affect the serum lipids and abdominal fat percentage. These results reveal the potential of the AMP used in aquaculture to regulate lipid metabolism disorders induced by the HFD.

Evaluation of quercetin in alleviating the negative effects of high soybean meal diet on spotted sea bass Lateolabrax maculatus.

The aim of this study was to investigate the effects of quercetin (QUE) on alleviating the negative effects of high soybean meal diet for spotted sea bass Lateolabrax maculatus. A healthy control group fed a 44% fishmeal diet was used, while the induction control group replaced 50% fishmeal with soybean meal. Subsequently, QUE was added at concentrations of 0.25, 0.50, 0.75, and 1.00 g/kg in the experimental groups. A total of 540 tailed spotted sea bass were randomly divided into 6 groups and fed the corresponding diet for 56 days. The results showed that 40% soybean meal significantly decreased the growth performance and immunity, increased the intestinal mucosal permeability, and caused damage to the intestinal tissue morphology; moreover, there were alterations observed in the composition of the intestinal microbiota, accompanied by detectable levels of saponins in the metabolites. However, the addition of QUE did not yield significant changes in growth performance; instead, it notably reduced the permeability of the intestinal mucosa, improved the body's immunity and the structural integrity of the intestinal tissue, increased the proportion of Proteobacteria, and enhanced the richness and diversity of intestinal microorganisms to a certain extent. In addition, QUE up-regulate the metabolism of amino acids and their derivatives and energy-related metabolites such as uridine and guanosine; furthermore, it appears to regulate transporters through the ABC transporters pathway to promote the absorption and utilization of QUE by enterocytes.

Effects of Lycium barbarum polysaccharides supplemented to high soybean meal diet on immunity and hepatic health of spotted sea bass Lateolabrax maculatus.

High soybean meal diet (HSBMD) decreased the immunity and damaged the liver health of spotted sea bass; in this study, Lycium barbarum polysaccharides (LBP) was added to HSBMD to explore its effects on the immunity and liver health. The diet with 44% fish meal content was designed as a blank control. On this basis, soybean meal was used to replace 50% fish meal as HSBMD, and LBP was added in HSBMD in gradient (1.0, 1.5, 2.0 g/kg) as the experimental diet. 225-tailed spotted sea bass with initial body weight of 44.52 ± 0.24 g were randomly divided into 5 groups and fed the corresponding diet for 52 days, respectively. The results show that: after ingestion of HSBMD, the immunity of spotted sea bass decreased slightly and hepatic tissue was severely damaged. And the addition of LBP significantly improved the immune capacity and protected the hepatic health. Specifically, the activities of serum lysozyme (LZM), immunoglobulin M (IgM), liver acid phosphatase (ACP) and alkaline phosphatase (AKP) were increased, and serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were significantly decreased, and hepatic morphology was improved. In the analysis of transcriptome results, it was found that toll-like receptor 3 (TLR3) and toll-like receptor 5 (TLR5) were down-regulated in toll-like receptor signaling pathway. And LBP may protect hepatic health by regulating Glycolysis/Gluconeogenesis, Insulin signaling pathway, Steroid biosynthesis and other glucolipid-related pathways. In conclusion, the addition of LBP in HSBMD can improve the immunity and protect the hepatic health of spotted sea bass, and its mechanism may be related to glucose and lipid metabolism.

Effects of Mulberry Leaf Extract on the Liver Function of Juvenile Spotted Sea Bass (Lateolabrax maculatus).

In order to explore the effect of mulberry leaf extract (ELM) on the liver function of spotted sea bass, 360 fish with healthy constitution (average body weight 9.00 ± 0.02 g) were selected and randomly divided into six groups with three repetitions, and six groups of fish were randomly placed into 18 test tanks (200 L) with 20 fish per tank for the 52-day feeding test. Every day, the fish were fed the experimental feed with different concentrations (0, 3, 6, 9, 12, 15 g/kg) to the level of apparent satiation, with a crude protein content of 48.0% and a crude fat content of 8.6%. And the water temperature was maintained at 25-28°C with a salinity of 0.5%-1‰. After feeding, five fish were randomly selected to collect their livers and serum for detection of indicators. The results showed that, compared with the control group, ELM significantly increased the activities of lipase (LPS) and trypsin (TRS) in the liver, and reached the highest level when the amount of ELM added was 6 g/kg (P < 0.05). ELM significantly increased the activities of lactate dehydrogenase (LDH) and glutamic-oxaloacetic transaminase (GOT) involved in the metabolic process in liver tissue, and GOT activity reached the highest when ELM was added at 9 g/kg, and LDH activity reached the highest when ELM was added at 15 g/kg (P < 0.05). ELM had no significant effect on liver antioxidant enzymes (P > 0.05), but the content of malondialdehyde was significantly reduced (P < 0.05). Compared with the control group, ELM significantly increased the activities of AKP and ACP in the liver, and the AKP activity reached the highest when the ELM addition amount was 3 g/kg, and the ACP activity reached the highest when the ELM addition amount was 9 g/kg (P < 0.05). Through comparative transcriptomic analysis, it was indicated that ELM enhanced the hepatic lipids and carbohydrates metabolism ability, as manifested in the upregulation of expression of phosphatidate phosphatase, glucuronosyltransferase, inositol oxygenase, carbonic anhydrase, and cytochrome c oxidase subunit 2. ELM can also increase the expression of signal transducer and activator of transcription 1, ATP-dependent RNA helicase and C-X-C motif chemokine 9 involved in the immune process. The above results show that the ELM can enhance the digestion, metabolism, and immunity of the liver by increasing the activity of digestive enzymes, metabolic enzymes, and the expression of metabolism and immune regulation genes. This study provides a theoretical basis for the application of ELM in the cultivation of spotted sea bass by exploring the effect of ELM on the liver function of spotted sea bass.

Effect of Supplementation of Chlorogenic Acid to High-Fat Diet on Growth, Lipid Metabolism, Intestinal and Hepatic Histology, and Gut Microbiota of Spotted Sea Bass (Lateolabrax maculatus).

The study investigated the impact of chlorogenic acid (CGA) supplementation in a high-fat diet (HFD) on growth, lipid metabolism, intestinal and hepatic histology, as well as gut microbiota in spotted sea bass. A total of 540 fish were fed six experimental diets, including a normal fat diet (NFD), a high-fat diet (HFD), and HFD supplemented with 100, 200, 300, and 400 mg/kg CGA (named HFD1, HFD2, HFD3, and HFD4, respectively) for 7 weeks. The results showed that HFD feeding increased growth and hepatic lipid deposition compared to that in the NFD group. Inclusion of 300 mg/kg CGA in HFD decreased the HFD-induced hyperlipemia (p < 0.05). Additionally, compared to the HFD group, the HFD4 group showed significant reductions in serum aspartate transaminase (AST) and alanine transaminase (ALT) levels as well as hepatic malondialdehyde (MDA) content, while also improving liver total antioxidant capacity (T-AOC) (p < 0.05). In the CGA-containing groups, hepatocytes were arranged more neatly than those in the HFD group, and there was a reduction in lipid deposition and hemolysis in the liver. Supplementation of CGA had effects on intestinal structure including an increase in mucosal thickness, as well as villus number and width. The diversity of intestinal flora in the CGA-containing groups was higher than those in the HFD group, and supplementation of 200 mg/kg CGA significantly increased the abundance of intestinal bacteria (p < 0.05). HFD4 feeding increased the intestinal Bacteroidetes to Firmicutes ratio and decreased the abundance of Vibrio. The highest value abundance of Actinobacteriota was found in the HFD2 group. Overall, HFD caused negative effects, and supplementation of 200-400 mg/kg CGA to HFD improved fat deposition, lipid metabolic disorders and liver and gut histology, and increased gut bacterial diversity in spotted sea bass.

A DFT Study of Volatile Organic Compounds Detection on Pristine and Pt-Decorated SnS Monolayers.

Real-time monitoring of volatile organic compounds (VOCs) is crucial for both industrial production and daily life. However, the non-reactive nature of VOCs and their low concentrations pose a significant challenge for developing sensors. In this study, we investigated the adsorption behaviors of typical VOCs (C2H4, C2H6, and C6H6), on pristine and Pt-decorated SnS monolayers using density functional theory (DFT) calculations. Pristine SnS monolayers have limited charge transfer and long adsorption distances to VOC molecules, resulting in VOC insensitivity. The introduction of Pt atoms promotes charge transfer, creates new energy levels, and increases the overlap of the density of states, thereby enhancing electron excitation and improving gas sensitivity. Pt-decorated SnS monolayers exhibited high sensitivities of 241,921.7%, 35.7%, and 74.3% towards C2H4, C2H6, and C6H6, respectively. These values are 142,306.9, 23.8, and 82.6 times higher than those of pristine SnS monolayers, respectively. Moreover, the moderate adsorption energies of adsorbing C2H6 and C6H6 molecules ensure that Pt-decorated SnS monolayers possess good reversibility with a short recovery time at 298 K. When heated to 498 K, C2H4 molecules desorbs from the surface of Pt-decorated SnS monolayer in 162.33 s. Our results indicate that Pt-decorated SnS monolayers could be superior candidates for sensing VOCs with high selectivity, sensitivity, and reversibility.

Effects of dietary Clostridium butyricum on the growth performance, digestion, and intestinal health of spotted sea bass (Lateolabrax maculatus).

Clostridium butyricum (CB) is known to promote growth, enhance immunity, promote digestion, and improve intestinal health. In this study, we investigated the effects of CB in the feed on growth performance, digestion, and intestinal health of juvenile spotted sea bass. To provide a theoretical basis for the development and application of CB in the feed of spotted sea bass, a total of 450 spotted sea bass with an initial body weight of (9.58 ± 0.05) g were randomly divided into six groups. Gradient levels with 0, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% of CB (1×109 cfu/g) were supplemented into diets, designated as CC, CB1, CB2, CB3, CB4, and CB5, respectively. Each group was fed for 54 days. Our results suggest that dietary 0.2% and 0.3% of CB can significantly increase the weight gain (WG) and specific growth rate (SGR) of spotted sea bass. The addition of CB significantly increased intestinal amylase activity, intestinal villus length, intestinal villus width, and intestinal muscle thickness. Similarly, CB supplementation increased the expression of tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8). Sequence analysis of the bacterial 16S rDNA region showed that dietary CB altered the intestinal microbiota profile of juvenile spotted sea bass, increasing the dominant bacteria in the intestine and decreasing the harmful bacteria. Overall, dietary addition of CB can improve growth performance, enhance intestinal immunity, improve intestinal flora structure, and comprehensively improve the health of spotted sea bass.

Lycium barbarum polysaccharides improve lipid metabolism disorders of spotted sea bass Lateolabrax maculatus induced by high lipid diet.

This experiment explored the effects of Lycium barbarum polysaccharides (LBP) on lipid metabolism of spotted sea bass Lateolabrax maculatus. Blank and experimental control diets with 100 and 150 g/kg lipid were designed, respectively, and three dosages of LBP (0.75, 1.00, 1.25 g/kg) were supplemented in the experimental control diet. A total 375 of spotted sea bass (19.33 ± 0.15) g were divided into 5 groups, and were given experimental diets for 56 days, respectively. Results showed fish were induced to lipid metabolism disorders with dietary 150 g/kg lipid intake, which manifested in reduced feeding, oxidative stress, elevated serum lipid, and more severe hepatic damage. Dietary LBP improved the lipid metabolism disorders of fish, as indicated by significant enhancements in weight gain, digestion, superoxide dismutase activity, and decreases in malonaldehyde content, and activity of alanine aminotransferase and aspartate aminotransferase. Accordingly, an improvement in the hepatic morphological and expression of lipid metabolism related genes, including FAS, PPAR-α, CPT1 and ATGL, was observed. Nevertheless, no significant variation in serum triglyceride and total cholesterol was observed. Overall, dietary LBP can improve the growth, digestion, antioxidant capacity, and liver health of spotted sea bass, thereby improving the lipid metabolism disorders induced by 150 g/kg dietary lipid intake.

Effects of Astragalus membranaceus Polysaccharides on Growth Performance, Physiological and Biochemical Parameters, and Expression of Genes Related to Lipid Metabolism of Spotted Sea Bass, Lateolabrax maculatus.

This experiment investigated the effects of Astragalus membranaceus polysaccharides (AMP) on growth, physiological and biochemical parameters, and the expression of lipid metabolism-related genes in spotted sea bass, Lateolabrax maculatus. A total of 450 spotted sea bass (10.44 ± 0.09 g) were divided into six groups and were given diets with different levels of AMP (0, 0.2, 0.4, 0.6, 0.8, and 1.0 g/kg) for 28 days, respectively. Results indicated that dietary intake of AMP significantly improved fish weight gain, specific growth rate, feed conversion, and trypsin activity. Meanwhile, fish fed with AMP manifested significantly higher serum total antioxidant capacity and activity of hepatic superoxide dismutase, catalase, and lysozyme. Lower triglyceride and total cholesterol were noted in fish fed with AMP (P < 0.05). Moreover, hepatic ACC1 and ACC2 were downregulated by dietary intake of AMP, and PPAR-α, CPT1, and HSL were upregulated accordingly (P < 0.05). Parameters with significant difference were analyzed by quadratic regression analysis, and results showed that 0.6881 g/kg of AMP is the optimal dosage for spotted sea bass in size (10.44 ± 0.09 g). In conclusion, dietary intake of AMP can improve the growth, physiological status, and lipid metabolism of spotted sea bass, thereby indicating its promise as a potential dietary supplement.

Effects of heat stress on physiological parameters, biochemical parameters and expression of heat stress protein gene in Lateolabraxmaculatus.

With global warming and the increasing frequency of extreme heat, we have to consider the heat tolerance of fish to sudden high temperatures. This study investigated the effects of high temperature (32 °C) on physiology and biochemistry and heat shock proteins (HSPs) gene of spotted sea bass (Lateolabrax maculatus). The spotted sea bass (14.7 ± 1.54 g) temporarily cultured at 26 °C was directly transferred to the 32 °C high temperature group, and the gill morphology, liver antioxidant activity, respiratory metabolism related enzyme activity and the expression of five HSP70 family members genes were measured at 3, 6, 9, 12, 24, 48, 72, and 96 h. The results showed that 32 °C had damage effect on gill tissue and antioxidant system, and the damage degree increased with high temperature. Respiratory rate and malondialdehyde increased gradually with the continuous heat stress. Superoxide dismutase and total antioxidant capacity increased briefly and then decreased continuously. Succinate dehydrogenase decreased to the lowest value at 24 h and then continued to increase. Lactate dehydrogenase decreased continuously; the expression of HSP70 increased rapidly and then decreased. These results indicated that the antioxidant system and HSP70 were activated under heat stress condition and provided protection to the body, but with the continuous high temperature, the protective effect was limited, and the fish body was irreversibly damaged. It is necessary to pay close attention to the temperature change in the production practice of spotted sea bass to reduce the influence caused by high temperature.

Effects of dietary asafoetida (Ferula sinkiangensis K. M. Shen) levels on feeding attraction activity, growth performance, healthiness, and digestive enzyme activity in juvenile Lateolabrax japonicus.

The study was to investigate effects of asafoetida (Ferula sinkiangensis K. M. Shen) powder on feeding attraction activity (FAA), growth performance, healthiness, and digestive enzyme activity of juvenile Lateolabrax japonicus. Six concentration levels (0, 5, 10, 15, 20, and 25 g/kg diets) were formulated for luring and feeding experiment. Results showed that asafoetida could stimulate the appetite of L. japonicus at the dietary levels from 10 to 25 g/kg; reduce the feed conversion ratio (FCR) and feed intake (FI) at 10-20 g/kg; increase the weight gain (WG) and specific growth rate (SGR) at 5-10 g/kg; increase the hepatosomatic index (HSI), body crude lipid content, serum total protein (TP) content, and lysozyme activity at 10-15 g/kg; decrease the moisture at 10-15 g/kg; and increase the serum total superoxide dismutase (T-SOD) activity at 5-15 g/kg, when compared with the control group (p < 0.05). Digestive enzyme activities including amylase (AMS) and trypsin in the intestine were significantly affected by the asafoetida powder (p < 0.05). Regression analyses between the FAA, FCR, WG, SGR, HSI, LZM, T-SOD, AMS, trypsin, and the dietary asafoetida powder levels showed that the optimal additional amount was 16.95, 13.65, 8.36, 8.15, 15.45, 9.94, 8.75, 11.77, and 7.07 g/kg, respectively, indicating that the optimal amount of asafoetida powder was located in 7.07-16.95 g/kg diet. However, combined with the significant difference analyses obtained from the current study, we would suggest the additive suitable dosage was 10 g/kg.

Effects of root exudates on the activation and remediation of cadmium ion in contaminated soils.

To screen out plants with hyperaccumulation of heavy metals and explore the effects of root exudates on the phytoremediation in contaminated soils. The germination rates of five plants including Lolium perenne L. (L. perenne), Sorghum sudanense (Piper) Stapf. (S. sudanense), Pennisetum alopecuroides (L.) Spreng. (P. alopecuroides), Medicago sativa L. (M. sativa), and Trifolium repens L. (T. repens) in different concentrations of cadmium ion solution (0-100 mg/kg) were determined. The growth adaptability of these five plants under conditions of contaminated soils with the above cadmium ion concentrations was also evaluated. S. sudanense and P. alopecuroides had higher germination rates and better growth than the three other plants and were selected as the latter experimental varieties. The activation amounts of cadmium ion in soils were measured using AAS in the presence of three types of root secretions (citric acid, glycine, and maltose) with different concentrations (10-500 mmol/L). The activation amounts decrease in the following order: citric acid > glycine > maltose. The effect of these three root exudates on the removal of cadmium-contaminated soils in combination with S. sudanense and P. alopecuroides was also tested. For S. sudanense and P. alopecuroides, the maximum biomass and removal rate reaches the maximum at 100 mmol/L of citric acid. Conversely, low concentrations (approximately 10-50 mmol/L) of glycine and maltose are more effective for plant growth and phytoremediation. The addition of citric acid at 100 mmol/L and approximately 10-50 mmol/L of glycine and maltose can effectively promote the transfer of cadmium ion from roots to leaves and the accumulation of cadmium ion in leaves.

Physicochemical and Functional Properties of Type I Collagens in Red Stingray (Dasyatis akajei) Skin.

Collagen is widely used in the pharmaceutical, tissue engineering, nutraceutical, and cosmetic industries. In this study, acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were extracted from the skin of red stingray, and its physicochemical and functional properties were investigated. The yields of ASC and PSC were 33.95 ± 0.7% and 37.18 ± 0.71% (on a dry weight basis), respectively. ASC and PSC were identified as type I collagen by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) analysis, possessing a complete triple helix structure as determined by UV absorption, Fourier transform infrared, circular dichroism, and X-ray diffraction spectroscopy. Contact angle experiments indicated that PSC was more hydrophobic than ASC. Thermal stability tests revealed that the melting temperature of PSC from red stingray skin was higher than that of PSC from duck skin, and the difference in the melting temperature between these two PSCs was 9.24 °C. Additionally, both ASC and PSC were functionally superior to some other proteins from terrestrial sources, such as scallop gonad protein, whey protein, and goose liver protein. These results suggest that PSC from red stingray skin could be used instead of terrestrial animal collagen in drugs, foods, cosmetics, and biological functional materials, and as scaffolds for bone regeneration.

Macrocyclic Compounds for Drug and Gene Delivery in Immune-Modulating Therapy.

For decades, macrocyclic compounds have been widely applied in various fields owing to essential physicochemical properties such as their rigid cyclic structures, geometric dimensions (diameter and height), hydrophobic cavity, and hydrophilic interface. This review is an attempt to summarize various research accomplishments involving macrocyclic compounds for drug and gene delivery in immune-modulating therapies: the structures and benefits of main host molecules, their mechanisms regulating the immune system from cell uptake to activation of dendritic cells and T helper lymphocytes, as well as their potential immunotherapy for different diseases. Macrocyclic compounds including cucurbiturils (CBs), calixarenes, pillararenes, cyclodextrins (CyDs), macrocyclic peptides and metallo-supramolecular compounds, have their own unique physicochemical properties and functional derivatizations that enable to improve the biocompatibility, responsiveness to stimuli, and effectiveness of immune-modulating therapy. Based on abundant clarifications of the biological immunity mechanisms, representative constructions of macrocyclic compounds for immune therapies have been conducted for the investigation of treatment of different diseases including cancer, atherosclerosis, Niemann-Pick type C1 disease (NPC1), diabetes, and inflammations. Although there are critical challenges that remain to be conquered, we believe the future of macrocyclic compounds in the immune-modulating therapy must be bright.

Light-enhanced hypoxia-responsive nanoparticles for deep tumor penetration and combined chemo-photodynamic therapy.

Herein, we report a light-enhanced hypoxia-responsive nanoparticle for synergic treatment of solid tumors. The conversion of oxygen in the tumor exterior induced ROS and the continuous consumption of oxygen amplified the hypoxia conditions in the tumor, which enhanced the surface-to-core penetration of nanoparticles into the hypoxia central tissue.

Selection of aptamers against inactive Vibrio alginolyticus and application in a qualitative detection assay.

Aptamers against inactive Vibrio alginolyticus were selected from an 82-nt ssDNA random library by systematic evolution of ligands by exponential enrichment. After 15 rounds of selection, the final pool of aptamers was highly specific for inactivated V. alginolyticus and had a dissociation constant of 27.5 ± 9.2 nM. Using these aptamers and PCR, V. alginolyticus could be detected at 100 cells/ml. Sequencing of the final pool of aptamers revealed that some sequences, termed high-frequency aptamers, appeared more than once; these may be of practical application. All sequences obtained were divided into nine families according to their homology tree, some conserved sequences were also found in each of the six families. One sequence was found in significant proportions of the aptamers, suggesting that this conserved sequence might be important for forming the three-dimensional aptamer structure.

Preparation and fluoroimmunoassay application of new red-region fluorescent silica nanoparticles.

This is the first report on the preparation and utilization of a novel red-region fluorescent dye (tetracarboxy aluminum phthalocyanine) doped silica nanoparticles. In these nanoparticles, the tetracarboxy aluminum phthalocyanine molecules were covalently bound to silica matrix to protect the dye leaking from nanoparticles in bio-applications. The surface of the nanoparticles was modified by amino groups and easily bioconjugated with goat anti-human IgG antibody. By employing these nanoparticles as fluorescent probe, a sensitive fluoroimmunoassay method has been developed for the determination of trace level of human IgG. The calibration graph for human IgG was linear over the range of 0-500 ng mL(-1) with a detection limit of 1.6 ng mL(-1). Compared with the corresponding system using free AlC(4)Pc as a probe for determining human IgG, the sensitivity of the proposed system was notably increased. The method was applied to the analysis of human IgG in human sera with satisfactory results.