Naringenin inhibits APAP-induced acute liver injury through activating PPARA-dependent signaling pathway.

Acute liver injury (ALI) refers to the damage to the liver cells of patients due to drugs, food, and diseases. In this work, we used a network pharmacology approach to analyze the relevant targets and pathways of the active ingredients in Citri Reticulatae Pericarpium (CRP) for the treatment of ALI and conducted systematic validation through in vivo and in vitro experiments. The network pharmacologic results predicted that naringenin (NIN) was the main active component of CRP in the treatment of ALI. GO functional annotation and KEGG pathway enrichment showed that its mechanism may be related to the regulation of PPARA signaling pathway, PPARG signaling pathway, AKT1 signaling pathway, MAPK3 signaling pathway and other signaling pathways. The results of in vivo experiments showed that (NIN) could reduce the liver lesions, liver adipose lesions, hepatocyte injury and apoptosis in mice with APAP-induced ALI, and reduce the oxidative stress damage of mouse liver cells and the inflammation-related factors to regulate ALI. In vitro experiments showed that NIN could inhibit the proliferation, oxidative stress and inflammation of APAP-induced LO2 cells, promote APAP-induced apoptosis of LO2 cells, and regulate the expression of apoptotic genes in acute liver injury. Further studies showed that NIN inhibited APAP-induced ALI mainly by regulating the PPARA-dependent signaling pathway. In conclusion, this study provides a preliminary theoretical basis for the screening of active compounds in CRP for the prevention and treatment of ALI.

Dictamnine Ameliorates DNFB-Induced Atopic Dermatitis Like Skin Lesions in Mice by Inhibiting M1 Macrophage Polarization and Promoting Autophagy.

Autophagy and M1 macrophage polarization play important roles in the regulation of inflammation in atopic dermatitis (AD). Dictamnine is one of the main ingredients in Cortex Dictamni, a widely used traditional Chinese medicine for the treatment of dermatitis. In the present study, we investigated the anti-inflammatory effects of dictamnine on AD like skin lesions and M1 macrophage polarization. A 2,4-dinitrofluorobenzene (DNFB) triggered AD like skin lesions models in mice was established to identify the ameliorative effects of dictamnine on AD in vivo. In addition, an M1 macrophage polarization model was co-stimulated by lipopolysaccharide (LPS) and interferon-γ (IFN-γ) using phorbol myristate acetate (PMA) differentiated THP-1 cells, to investigate the effect of dictamnine on promoting autophagy and inhibiting inflammatory factor release. Dictamnine suppressed DNFB-induced skin inflammation by inhibiting M1 macrophage polarization, up-regulating the expression of microtubule-associated protein 1A/1B-light chain 3 (LC3) expression, and promoting macrophage autophagy at inflammatory sites. Dictamnine also could reduce the release of interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1), and interleukin-8 (IL-8), and down-regulate the mRNA expression of these genes in LPS-IFN-γ triggered M1 polarized macrophages. Dictamnine ameliorates AD like skin lesions by inhibiting M1 macrophage polarization and promoting autophagy. Hence, dictamnine is expected to be a potential therapeutic candidate for AD.

Vegetation restoration in an alpine meadow: Insights from soil microbial communities and resource limitation across soil depth.

Aboveground vegetation restoration shapes the soil microbial community structure and affects microbial resource acquisition. However, the changes in soil microbial resource limitation in subsoil during vegetation restoration are still unclear. In this study, the microbial community structure and resource limitation in an alpine meadow soil profile that had undergone natural restoration for short-term (4-year) and long-term (10-year) restoration in response to vegetation restoration were explored through high-throughput sequencing analysis and extracellular enzyme stoichiometry (EES). There was no significant difference in microbial composition and α diversity between short- and long-term restoration soils. Soil microorganisms in this alpine meadow were mainly limited by phosphorus. Carbon limitation of soil microorganisms was significantly decreased in each layer (0-15, 15-30, 30-45, 45-60, and 60-80 cm corresponding to L1, L2, L3, L4, and L5, respectively) of long-term restoration soils when compared to that of the short-term restoration soil layers, while phosphorus limitation of microorganisms in subsoil (60-80 cm) was significantly increased by 17.38%. Soil nutrients, pH, moisture content, and microbial composition are the main drivers of microbial resource limitation in restoration, and their effects on microbial resource limitation were different in short- and long-term restoration. Meanwhile, key microbial taxa have a significant impact on microbial resource limitation, especially in short-term restoration soils. This study suggested that vegetation restoration significantly affected soil microbial resource limitation, and could alleviate microbial resource limitations by adding nutrients, thus accelerating the process of vegetation restoration in alpine ecosystems.

Effects of hypoxia and reoxygenation on oxidative stress, histological structure, and apoptosis in a new hypoxia-tolerant variety of blunt snout bream (Megalobrama amblycephala).

A new hypoxia-tolerant variety of blunt snout bream was obtained by successive breeding of the wild population, which markedly improved hypoxia tolerance. In this study, the hypoxia-tolerant variety was exposed to hypoxia (2.0 mg O2·L-1) for 4, 7 days. The contents of blood biochemical indicators including the number of red blood cells (RBC), total cholesterol (T-CHO), total protein (TP), triglyceride (TG), glucose (GLU), and lactic acid (LD) increased significantly (P < 0.05) under hypoxia. The glycogen content in the liver and muscle decreased significantly (P < 0.05) and the LD content in the brain, muscle and liver increased significantly (P < 0.05) under hypoxia. The levels of oxidative stress-related indicators i.e., superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), catalase (CAT), and total antioxidant capacity (T-AOC) also changed significantly (P < 0.05) in the heart, liver, and intestine of the new variety under hypoxia. Additionally, hypoxia has caused injuries to the heart, liver, and intestine, but it shows amazing repair ability during reoxygenation. The apoptotic cells and apoptosis rate in the heart, liver, and intestine increased under hypoxia. Under hypoxia, the expression of the B-cell lymphomas 2 (Bcl-2) gene in the heart, liver, and intestine was significantly (P < 0.05) down-regulated, while the expression of the BCL2-associated agonist of cell death (Bad) gene was significantly (P < 0.05) up-regulated. These results are of great significance for enriching the basic data of blunt snout bream new variety in response to hypoxia and promoting the healthy development of its culture industry.

Silibinin attenuated pseudo-allergic reactions and mast cell degranulation via PLCγ and PI3K/Akt signaling pathway.

Anaphylaxis is a type of potentially fatal hypersensitivity reaction resulting from the activation of mast cells. Many endogenous or exogenous factors could cause this reaction. Silibinin is the main chemical component of silymarin and has been reported to have pharmacological activities. However, the anti-allergic reaction effect of silibinin has not yet been investigated. This study aimed to evaluate the effect of silibinin to attenuate pseudo-allergic reactions in vivo and to investigate the underlying mechanism in vitro. In this study, calcium imaging was used to assess Ca2+ mobilization. The levels of cytokines and chemokines, released by stimulated mast cells, were measured using enzyme immunoassay kits. The activity of silibinin was evaluated in a mouse model of passive cutaneous anaphylaxis (PCA). Western blotting was used to explore the related molecular signaling pathways. In results, silibinin markedly inhibited mast cell degranulation, calcium mobilization, and preventing the release of cytokines and chemokines in a dose-dependent manner via the PLCγ and PI3K/Akt signaling pathway. Silibinin also attenuated PCA in a dose-dependent manner. In summary, silibinin has an anti-pseudo-allergic pharmacological activity, which makes it a potential candidate for the development of a novel agent to arrest pseudo-allergic reactions.

Myricetin alleviated immunologic contact urticaria and mast cell degranulation via the PI3K/Akt/NF-κB pathway.

Immunologic contact urticaria (ICU) is characterized by the wheal and flare reaction from direct contact with a chemical or protein agent, which involves a type I hypersensitivity mediated by allergen-specific immunoglobulin E (sIgE). Myricetin (Myr), a bioactive flavonoid, exhibits antiinflammatory activities. Our results showed that treatment with Myr could alleviate ICU symptoms, including a decrease in the number of wheals and scratching, and inhibit ear swelling in the IgE/DNFB-induced mice. The serum level of IgE, histamine, interleukin (IL)-4, TNF-α, and MCP-1 were reduced in Myr-treated mice. Myr also attenuated mast cells (MCs) degranulation and H-PGDS, TSLP, IL-33, PI3K, Akt, and NF-κB mRNA levels in ICU model. The IgE-mediated anaphylaxis mouse models demonstrated anti-allergic effects of Myr. In vitro analysis showed that Myr reduced IgE-induced calcium (Ca2+ ) influx, suppressed degranulation, and chemokine release in LAD2 cells (human primary mast cells). Myr can significantly inhibited PLCγ1, Akt, NF-κB, and p38 phosphorylation. In conclusion, the study demonstrated that Myr alleviate ICU symptoms and inhibit mast cell activation via PI3K/Akt/NF-κB signal pathway.

Identification of the Constituents of Ethyl Acetate Fraction from Smilax china L. and Determination of Xanthine Oxidase Inhibitory Properties.

The aim of this work was to investigate the xanthine oxidase (XO)-inhibitory activity of ethanol extracts from Smilax china L. and to identify the active compounds in the ethyl acetate (EtOAc) fraction. Extraction of ethanol extracts from Smilax china L. and then ethanol extracts were concentrated, and the polyphenolic compounds were extracted with petroleum ether (PE), chloroform, EtOAc, n-butanol (n-BuOH), and residual ethanol fractions. Their effects on XO activity were then compared separately. The polyphenolic components of the EtOAc fraction were identified by HPLC and HPLC-mass spectrometry (HPLC-MS) analysis. Kinetic analysis demonstrated that all these extracts showed XO-inhibitory properties, and among them the EtOAc fraction had the strongest inhibitory effect (IC50 = 101.04 µg/mL). The inhibitory constant (Ki) of the EtOAc fraction on XO activity was 65.20 µg/mL, showing excellent inhibition on XO in the competitive mode. Sixteen compounds were identified from the EtOAc fraction. The study demonstrates that the EtOAc fraction of Smilax china L. may be a potential functional food to inhibit XO activity.

Functional exploration of SNP mutations in HIF2αb gene correlated with hypoxia tolerance in blunt snout bream (Megalobrama amblycephala).

Blunt snout bream (Megalobrama amblycephala) is sensitive to hypoxia environment. Hypoxia-inducible factor (HIF) is the most critical factor in the HIF pathway, which strictly regulates the hypoxia stress process of fish. In this study, we found six hifα genes in blunt snout bream that demonstrated different expressions under hypoxia conditions. In HEK293T cells, all six hifαs were detected to activate the HRE region by luciferase reporter assay. More importantly, we identified two linkage-disequilibrium SNP sites at exon 203 and 752 of the hif2αb gene in blunt snout bream. Haplotype II (A203A752) and its homozygous diplotype II (A203A203A752A752) appeared frequently in a selected strain of blunt snout bream with hypoxia tolerance. Diplotype II has a lower oxygen tension threshold for loss of equilibrium (LOEcrit) over a similar range of temperatures. Moreover, its erythrocyte number increased significantly (p < 0.05) than those in diplotype I and diplotype III strains at 48 h of hypoxia. The enzymes related with hypoxia tolerant traits, i.e., reduced glutathione, superoxide dismutase, and catalase, were also significantly (p < 0.05) induced in diplotype II than in diplotype I or III. In addition, the expression of epo in the liver of diplotype II was significantly (p < 0.01) higher than that in the diplotype I or III strains at 48 h of hypoxia. Taken together, our results found that the hypoxia-tolerant-related diplotype II of hif2αb has the potential to be used as a molecular marker in future genetic breeding of hypoxia-tolerant strain.

Effects of hypoxia on the gill morphological structure, apoptosis and hypoxia-related gene expression in blunt snout bream (Megalobrama amblycephala).

The blunt snout bream (Megalobrama amblycephala) is a typical hypoxia-sensitive fish, and hypoxia stress leads to reduced vitality and yield during aquaculture. To explore the specific adaptation mechanism under hypoxia, the blunt snout bream was treated with hypoxia (DO = 2.0 ± 0.1 mg/L) for 24 h, followed by 3 h of recovery. Our results depicted that the gill filament structure of blunt snout bream changed after hypoxia. During hypoxia for 24 h, the gill filament structure was altered, including a more than 80% expansion of the lamellar respiratory surface area and a proportionate apoptosis decrease in interlamellar cell mass (ILCM) volume. Thus, the water-blood diffusion distance was shortened to less than 46%. During hypoxia for 24 h, the activity of ROS in gill tissue increased significantly (p < 0.05), while the mitochondrial membrane potential decreased significantly (p < 0.05). During hypoxia, mRNA expression level of anti-apoptotic gene Bcl-2 in the gills of blunt snout bream decreased significantly (p < 0.05), while the expression of pro-apoptotic gene Bax mRNA increased significantly (p < 0.05). Thus, the ratio of Bax/Bcl-2 mRNA increased in the gills of blunt snout bream to promote the activity of Caspase-3. Together, our results indicated hypoxia-induced apoptosis in the gills of blunt snout bream through the mitochondrial pathway. In addition, a decreased expression of Phd1 and an increased expression of Hif-1α in gills under hypoxia stress indicates that blunt snout bream may cope with hypoxia-induced apoptosis by enhancing the HIF pathway. These results provide new insights into fish's adaptation strategies and mechanisms of hypoxia.

Kazinol B protects H9c2 cardiomyocytes from hypoxia/reoxygenation-induced cardiac injury by modulating the AKT/AMPK/Nrf2 signalling pathway.

CONTEXT: Kazinol B (KB), an isoprenylated flavan derived from Broussonetia kazinoki Sieb. (Moraceae) root, has long been used in folk medicine. OBJECTIVE: This study examines the protective effects of KB and its underlying mechanisms in hypoxia and reoxygenation (H/R)-induced cardiac injury in H9c2 rat cardiac myoblasts. MATERIALS AND METHODS: H9c2 cells were incubated with various concentrations of KB (0, 0.3, 1, 3, 10 and 30 µM) for 2 h and then subjected to H/R insults. The protective effects of KB and its underlying mechanisms were explored. RESULTS: KB significantly elevated cell viability (1 µM, 1.21-fold; 3 µM, 1.36-fold, and 10 µM, 1.47-fold) and suppressed LDH release (1 µM, 0.77-fold; 3 µM, 0.68-fold, and 10 µM, 0.59-fold) in H/R-induced H9c2 cells. Further, 10 µM KB blocked apoptotic cascades, as shown by the Annexin-V/PI (0.41-fold), DNA fragmentation (0.51-fold), caspase-3 (0.52-fold), PARP activation (0.27-fold) and Bax/Bcl-2 expression (0.28-fold) assays. KB (10 µM) downregulated reactive oxygen species production (0.51-fold) and lipid peroxidation (0.48-fold); it upregulated the activities of GSH-Px (2.08-fold) and SOD (1.72-fold). KB (10 µM) induced Nrf2 nuclear accumulation (1.94-fold) and increased ARE promoter activity (2.15-fold), HO-1 expression (3.07-fold), AKT (3.07-fold) and AMPK (3.07-fold) phosphorylation. Nrf2 knockdown via using Nrf2 siRNA abrogated KB-mediated protective effects against H/R insults. Moreover, pharmacological inhibitors of AKT and AMPK also abrogated KB-induced Nrf2 activation and its protective function. DISCUSSION AND CONCLUSIONS: KB prevented H/R-induced cardiomyocyte injury via modulating the AKT and AMPK-mediated Nrf2 induction. KB might be a promising drug candidate for managing ischemic cardiac disorders.

Smilax china L. Polyphenols Improves Insulin Resistance and Obesity in High-fat Diet-induced Mice Through IRS/AKT-AMPK and NF-κB Signaling Pathways.

Smilax china L. is an important herb used in traditional Chinese medicine. In this study, the mechanism of Smilax china L. polyphenols (SCP) on insulin resistance and anti-obesity in mice induced by a high-fat diet (HFD) was investigated. Fifty female mice were randomly divided into five groups: control, HFD and low, medium, and high doses of SCP for 70 d. SCP significantly decreased intraperitoneal adipose tissue index, body weight gain, liver lipids, and serum inflammatory factor levels. Blood glucose and insulin concentrations, as well as insulin resistance index in SCP, were significantly lower than those in HFD. In addition, SCP markedly up-regulated the gene expression of glucose transporter 4 (GLUT4), insulin receptor substrate 1 (IRS1), insulin receptor substrate 2 (IRS2), serine-threonine kinase (AKT), Acyl-CoA oxidase (ACO), and protein kinase A (PKA), and down-regulated the expression of mammalian target of rapamycin complex 1 (mTORC1), sterol-responsive element-binding protein-1c (SREBP1c), fatty acid synthase (FAS), 3-hydroxy-3-methyl glutaryl coenzyme A reductase (HMGCR), and forkhead box protein O1 (FOXO1). SCP significantly increased the protein expression of AKT, GLUT4, AMP-activated protein kinase (AMPK), phosphorylated-AMPK (p-AMPK), phosphorylated-AKT (p-AKT), and uncoupling protein 1 (UCP-1), and decreased the expression of SREBP1c, FAS, HMGCR, phosphorylation of IKBα (p-IKBα), and nuclear factor kappa B subunit p65 (P65) in the liver. Overall, SCP effectively reduced HFD-induced insulin resistance and obesity in mice, partly through NF-κB and IRS/AKT-AMPK signaling pathways to regulate inflammatory factors. Therefore, SCP may improve lifestyle diseases.

The transcriptomic responses of blunt snout bream (Megalobrama amblycephala) to acute hypoxia stress alone, and in combination with bortezomib.

BACKGROUND: Blunt snout bream (Megalobrama amblycephala) is sensitive to hypoxia. A new blunt snout bream strain, "Pujiang No.2", was developed to overcome this shortcoming. As a proteasome inhibitor, bortezomib (PS-341) has been shown to affect the adaptation of cells to a hypoxic environment. In the present study, bortezomib was used to explore the hypoxia adaptation mechanism of "Pujiang No.2". We examined how acute hypoxia alone (hypoxia-treated, HN: 1.0 mg·L- 1), and in combination with bortezomib (hypoxia-bortezomib-treated, HB: Use 1 mg bortezomib for 1 kg fish), impacted the hepatic ultrastructure and transcriptome expression compared to control fish (normoxia-treated, NN). RESULTS: Hypoxia tolerance was significantly decreased in the bortezomib-treated group (LOEcrit, loss of equilibrium, 1.11 mg·L- 1 and 1.32 mg·L- 1) compared to the control group (LOEcrit, 0.73 mg·L- 1 and 0.85 mg·L- 1). The HB group had more severe liver injury than the HN group. Specifically, the activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the HB group (52.16 U/gprot, 32 U/gprot) were significantly (p < 0.01) higher than those in the HN group (32.85 U/gprot, 21. 68 U/gprot). In addition, more severe liver damage such as vacuoles, nuclear atrophy, and nuclear lysis were observed in the HB group. RNA-seq was performed on livers from the HN, HB and NN groups. KEGG pathway analysis disclosed that many DEGs (differently expressed genes) were enriched in the HIF-1, FOXO, MAPK, PI3K-Akt and AMPK signaling pathway and their downstream. CONCLUSION: We explored the adaptation mechanism of "Pujiang No.2" to hypoxia stress by using bortezomib, and combined with transcriptome analysis, accurately captured the genes related to hypoxia tolerance advantage.

Chromosome-level genome assembly of grass carp (Ctenopharyngodon idella) provides insights into its genome evolution.

BACKGROUND: The grass carp has great economic value and occupies an important evolutionary position. Genomic information regarding this species could help better understand its rapid growth rate as well as its unique body plan and environmental adaptation. RESULTS: We assembled the chromosome-level grass carp genome using the PacBio sequencing and chromosome structure capture technique. The final genome assembly has a total length of 893.2 Mb with a contig N50 of 19.3 Mb and a scaffold N50 of 35.7 Mb. About 99.85% of the assembled contigs were anchored into 24 chromosomes. Based on the prediction, this genome contained 30,342 protein-coding genes and 43.26% repetitive sequences. Furthermore, we determined that the large genome size can be attributed to the DNA-mediated transposable elements which accounted for 58.9% of the repetitive sequences in grass carp. We identified that the grass carp has only 24 pairs of chromosomes due to the fusion of two ancestral chromosomes. Enrichment analyses of significantly expanded and positively selected genes reflected evolutionary adaptation of grass carp to the feeding habits. We also detected the loss of conserved non-coding regulatory elements associated with the development of the immune system, nervous system, and digestive system, which may be critical for grass carp herbivorous traits. CONCLUSIONS: The high-quality reference genome reported here provides a valuable resource for the genetic improvement and molecular-guided breeding of the grass carp.

An SNP at the target site of cid-miR-nov-1043 in the TOLLIP 3' UTR decreases mortality rate in grass carp subjected to ENU-induced mutagenesis following grass carp reovirus infection.

N-ethyl-N-nitrosourea (ENU) selection is a useful technique to generate new mutations that may cause some functional changes in the gene. Through our previous genomic bulked segregant analysis (BSA), one single nucleotide polymorphism (SNP) at the 3' UTR of Toll interacting protein gene (TOLLIP982T>C) was identified in grass carp (Ctenopharyngodon idella) subjected to ENU-induced mutagenesis. We found that the overexpression of cid-miR-nov-1043 mimics significantly suppressed the luciferase activity of the TOLLIP 3' UTR, but TOLLIP982T>C mutation at the target site can decrease the binding affinity between the miRNA cid-miR-nov-1043 and TOLLIP 3' UTR, reducing the inhibition of TOLLIP mRNA transcription in grass carp subjected to ENU-induced mutagenesis. More importantly, we demonstrated that TOLLIP mRNA transcription levels in the gills, liver, kidney and the isolate white cells of the mutant grass carp were significantly (p < 0.01) higher than those in the corresponding tissues from the wild-type grass carp following infection with Grass Carp Reovirus (GCRV) for seven days, while the downstream gene of TOLLIP transforming growth factor ß-activated kinase 1 (TAK1) and TAK1-binding protein 1 (TAB1), were higher expressed in wild-type grass carp. As a negative regulator in the pro-inflammatory pathway of NF-κB, TOLLIP inhibits the excessive inflammation in ENU grass carp after GCRV infection. Consistent with the TOLLIP expression, histopathological results demonstrated more severe inflammation in wild-type grass carp, compared to the TOLLIP982T>C mutant grass carp on the seventh day. Severe inflammation will lead to thoroughly infiltration of chloride and inflammatory cells in the gill filaments. This seriously hindered the exchange of oxygen, which ultimately disrupted blood circulation. Meanwhile, the survival rate of the mutant grass carp was significantly (p < 0.01) higher than that of the wild-type grass carp, indicating that the TOLLIP982T>C mutants showed strong anti-viral abilities. Our results revealed that an SNP in the TOLLIP 3' UTR may contribute to the suppression of serve inflammation subjected to ENU-induced mutagenesis following GCRV infection, which may be helpful for future resistant breeding development of grass carp.

Analysis of the chemical components of pomelo peels (Citrus grandis [L.] Osbeck) from different cultivars by using supercritical CO2 fluid extraction and ultra-high-performance liquid chromatography-tandem mass spectrometry.

Five pomelo cultivars (i.e., Citrus grandis cv. Shatianyou, Citrus grandis cv. Guanximiyou, Citrus grandis cv. Yuhuanyou, Citrus grandis cv. Duweiwendanyou and Citrus grandis cv. Liangpingyou) from different origins in China were selected to analyze their components by using supercritical CO2 fluid extraction coupled with ultra-high-performance liquid chromatography-tandem mass spectrometry. A total of 45 compounds were identified in the supercritical CO2 fluid extracts of the pomelo peels from the five cultivars. These compounds included eight flavonoids, 18 coumarins, four organic acids, three aldehydes, and 12 other compounds, which were identified using the obtained MS data and by comparison with commercial standards, orbitrap Chinese Traditional Medicine Library, and previous literature. Twenty-five of the identified compounds were detected for the first time in the pomelo peel extracts. Results suggested that the pomelo peels of C. grandis cv. Shatianyou contained the most natural chemical compositions. The pooled result may offer scientific evidence for further development and utilization of pomelo peels and a route for screening appropriate varieties for various demands.

The anti-obesity and gut microbiota modulating effects of taxifolin in C57BL/6J mice fed with a high-fat diet.

BACKGROUND: Taxifolin is a natural dihydroflavonol found in many plants and health products. In the present study, its anti-obesity and gut microbiota modulating effects were studied. C57BL/6J mice were fed with a high-fat diet (HFD) supplemented with taxifolin (0, 0.5 and 1 mg mL-1 , respectively) in drinking water for 15 weeks. RESULTS: Taxifolin supplementation showed no influence on food and water intake. However, it decreased body weight gain, inhibited fat accumulation, and decreased total cholesterol and triacylglycerol level in mice liver. Taxifolin enhanced superoxide dismutase (SOD) activity in mice liver, which in turn protected the liver from lipid peroxidation damage. It also improved insulin resistance in obese mice. Metagenomic analysis of bacterial 16S rRNA demonstrated that HFD decreased gut microbiota diversity and caused dysbiosis. However, taxifolin improved the gut microbiota diversity and decreased the Firmicutes/Bacteroidetes ratio. In particular, it inhibited Proteobacteria from blooming, this being a signature of dysbiosis in gut microbiota. CONCLUSION: Taxifolin ameliorated the symptoms of obesity, hepatic steatosis, lipid peroxidation, insulin resistance, and gut microbiota dysbiosis in HFD fed C57BL/6J mice. © 2021 Society of Chemical Industry.

Effects of hypoxia and reoxygenation on gill remodeling, apoptosis, and oxidative stress in hypoxia-tolerant new variety blunt snout bream (Megalobrama amblycephala).

Blunt snout bream plays an important role in freshwater aquaculture in China, but the development of its culture industry has been restricted by increasing hypoxia problem. Through the breeding of wild blunt snout bream populations (F0), a hypoxia-tolerant new variety (F6) was obtained. In this study, the new variety was stressed under low oxygen concentration (2.0 mg·L-1) for 4 and 7 days, the morphological structure of the gill tissue showed a striking change, the interlamellar cell mass (ILCM) volume reduced significantly (P < 0.05), and the lamellar respiratory surface area enlarged significantly (P < 0.05), compared to normoxic controls. After 7 days of oxygen recovery, gill remodeling was completely reversed. Additionally, the TUNEL-positive apoptotic fluorescence signals increased in the gills exposed to hypoxia up to 4 and 7 days; the apoptosis rate also increased significantly (P < 0.05). Under 4 and 7 days of hypoxia stress, the expression of anti-apoptotic gene Bcl-2 in the gills downregulated significantly (P < 0.05), with the significantly (P < 0.05) upregulated expression of pro-apoptotic gene Bad. Furthermore, under hypoxia stress, the activity or content of oxidative stress-related enzymes (superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and glutathione (GSH)) in gill tissue increased to varying degrees compared to normoxic controls. These results offer a new perspective into the cellular and molecular mechanism of hypoxia-induced gill remodeling in blunt snout bream and a theoretical basis for its hypoxia adaptation mechanism.

Quercetin, Engelitin and Caffeic Acid of Smilax china L. Polyphenols, Stimulate 3T3-L1 Adipocytes to Brown-like Adipocytes Via ß3-AR/AMPK Signaling Pathway.

The aim of the present study was to investigate the browning effects mechanism of Smilax china L. polyphenols (SCLP) and its monomer. In this study, polyphenols (SCLP, engeletin, quercetin and caffeic acid) markedly suppressed lipid accumulation. Polyphenols significantly up-graded the expression of protein kinase A (PKA), adipose triglyceride lipase (ATGL), peroxisome proliferators-activated receptors alpha (PPARα), carnitine palmitoyl transferase (CPT) and acyl-CoA oxidase (ACO) to promote lipolysis and ß-oxidation. Moreover, polyphenols greatly enhanced mitochondrial biogenesis in adipocytes, as demonstrated by the expression of Nrf1 and Tfam were up-regulated. Furthermore, polyphenols treatment greatly up-regulated the browning program in adipocytes by increased brown-specific genes and proteins uncoupling protein 1 (UCP-1), peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) and PR domain containing 16 (PRDM16), as well as beige-specific genes (Tmem26, Tbx1, CD137, Cited1), especially engeletin. Further research found that the brown-specific markers were decreased by antagonist treatment of AMPK or ß3-AR, but polyphenols treatment reversed the effect of antagonists and improved the expression of UCP-1, PRDM16 and PGC-1α. In conclusion, these results indicated that polyphenols stimulate browning in adipocytes via activation of the ß3-AR/AMPK signaling pathway, and SCLP and its monomer may be worth investigating to prevent obesity.

Selection of functional EPHB2 genotypes from ENU mutated grass carp treated with GCRV.

BACKGROUND: N-ethyl-N-nitrosourea (ENU) mutagenesis is a useful method for the genetic engineering of plants, and the production of functional mutants in animal models including mice and zebrafish. Grass carp reovirus (GCRV) is a haemorrhagic disease of grass carp which has caused noteworthy losses in fingerlings over the last few years. To overcome this problem, we used ENU mutant grass carp in an attempt to identify functional resistance genes for future hereditary rearing projects in grass carp. RESULTS: This study used ENU-mutated grass carp to identify genetic markers associated with resistance to the haemorrhagic disease caused by GCRV. Bulked segregant analysis (BSA) was performed on two homozygous gynogenetic ENU grass carp groups who were susceptible or resistant to GCRV. This analysis identified 466,162 SNPs and 197,644 InDels within the genomes of these mixed pools with a total of 170 genes annotated in the associated region, including 49 genes with non-synonymous mutations at SNP sites and 25 genes with frame shift mutations at InDel sites. Of these 170 mutated genes, 5 randomly selected immune-related genes were shown to be more strongly expressed in the resistant group as compared to the susceptible animals. In addition, we found that one immune-related gene, EPHB2, presented with two heterozygous SNP mutations which altered the animal's responded to GCRV disease. These SNPs were found in the intron region of EPHB2 at positions 5859 (5859G > A) and 5968 (5968G > A) and were significantly (p = 0.002, 0.003) associated with resistance to GCRV. These SNP sites were also shown to correlate with the GCRV-resistant phenotype in these ENU grass carp. We also evaluated the mortality of the different ENU fish genotypes in response to GCRV and the SNPs in EPHB2. The outcomes of these evaluations will be useful in future selections of GCRV-resistant genes for genetic breeding in grass carp. CONCLUSION: Our results provide a proof of concept for the application of BSA-sequence analysis in detecting genes responsible for specific functional genotypes and may help to develop better methods for marker-assisted selection, especially for disease resistance in response to GCRV.

Exploring the fate of heavy metals from mining and smelting activities in soil-crop system in Baiyin, NW China.

The activity and fate of heavy metals (HMs) from mining and smelting activities in farmland soil is of great significance to effectively prevent the excessive enrichment of HMs in crops. This study focuses on Baiyin area, a typical mining city in northwest China. In this example, the sources, speciation, and fate of HMs in the farmland soil, and the migration and enrichment characteristics of HMs in the different parts of crops planted in different areas were studied in detail combining the chemical sequential extraction and Pb isotope approaches. Results showed that the mean anthropogenic contributions of HMs in farmland soils were approximately 85%, 88%, 76%, and 41% for the ore district (OD), Xidagou sewage irrigation area (XSIA), Dongdagou sewage irrigation area, and the Yellow River irrigation area, respectively, and the risk that HMs were excessively accumulated in crops in OD and XSIA was high. Compared with soil residual fractions, the isotope ratios 206Pb/207Pb in non-residual fractions (1.1304-1.1669) were closer to the values of local ores, suggesting that anthropogenic HMs from mining and smelting activities were mainly enriched in the non-residual fractions. The isotope ratios 206Pb/207Pb in crops (1.1398-1.1686) further confirmed that those anthropogenic HMs were more easily absorbed and concentrated by crops. HMs contents in leaves from OD and XSIA were generally higher than that in roots, suggesting that atmospheric deposition in OD and XSIA had a greater impact on the HMs concentration of crop leaves，while the excess rate of HMs in grain/fruit was the lowest in all parts of crops. The division and classification of crop planting in mining area can effectively help minimize the risk that HMs from anthropogenic source enter the human body through the food chain.