EPSTI1 promotes osteoclast differentiation and bone resorption by PKR/NF-κB signaling.

BACKGROUND: Epithelial stromal interaction 1 (EPSTI1) plays an important role in M1 macrophages, which induce osteoclastogenesis. One recent genome-wide association study (GWAS) involving 426,824 individuals has shown that EPSTI1 is strongly associated with osteoporosis (P < 5E-8). Therefore, we speculate that EPSTI1 participates in the modulation of osteoporosis through osteoclastogenesis. The roles of EPSTI1 in osteoclastogenesis and bone resorption remain unclear. METHODS: Femur specimens were collected from osteoporotic patients and control patients. Immunofluorescence staining was used to detect the expression of EPSTI1 and signaling pathways. The osteoclastic potential of RAW264.7 cells with Sh-EPSTI1 lentivirus infection was tested using tartrate-resistant acid phosphatase (TRAP) staining, western blotting, and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Western blotting was also used to examine signaling pathways. RESULTS: In this study, EPSTI1 was found to be significantly increased in tartrate-resistant acid phosphatase positive (ACP5+) osteoclasts of bone sections from osteoporotic patients. Next, we identified EPSTI1 as a positive regulator of osteoclastogenesis and osteoclast differentiation capability. Diminished EPSTI1 expression resulted in reduced osteoclastic resorption. Mechanistically, EPSTI1-driven osteoclastogenesis was regulated by NF-κB pathway, which was mediated by the phosphorylation of protein kinase R (p-PKR). Furthermore, EPSTI1 participating in the modulation of osteoporosis via PKR/NF-κB pathway was also verified in the bone samples of osteoporotic patients. CONCLUSIONS: Collectively, our findings suggest that EPSTI1 may regulate osteoclast differentiation and bone resorption through PKR/NF-κB pathway and in vivo experiments are needed to further verify EPSTI1 as the therapy target for osteoporosis.

Enhancement of autophagy can alleviate oxidative stress, inflammation, and apoptosis induced by ammonia stress in yellow catfish Pelteobagrus fulvidraco.

Ammonia in aquatic environments is toxic to fish, directly impacting their growth performance and development. Activation of autophagy can facilitate intracellular component renewal and enhance an organism's adaptability to adverse environments. Therefore, this study investigates the impact of autophagy on the yellow catfish under acute ammonia stress. In this study, the yellow catfish intraperitoneally injected with 0.9 % sodium chloride were placed with 0 (CON group) and 125 (HA group) mg/L T-AN (Total ammonia nitrogen) dechlorinated water. The yellow catfish intraperitoneally injected with 30 mg/kg fish CQ (Chloroquine, HA + CQ group) and 1.5 mg/kg fish RAPA (rapamycin, HA + RAPA group) were placed in dechlorinated water containing 125 mg/L T-AN. The results showed that activation of autophagy by injecting with RAPA can alleviate oxidative stress (catalase, superoxide dismutase, total antioxidant capacity significantly increased, H2O2 content significantly decreased), and inflammatory response (pro-inflammatory factors TNF-α, MyD88, IL 1-ß gene expression decreased significantly), apoptosis (baxa, Bcl2, Tgf-ß, Smad2, Caspase3, Caspase 9 gene expression decreased significantly) induced by ammonia stress. In addition, activation of autophagy in yellow catfish can enhance ammonia detoxification by promoting the urea cycle and synthesis of glutamine (the mRNA level of CPS Ⅰ, ARG, OTC, ASS, ASL, and GS increased in the HA + RAPA group). The data above demonstrates that activating autophagy can alleviate oxidative stress, inflammatory responses, and cell apoptosis induced by ammonia stress. Therefore, enhancing autophagy is proposed as a potential strategy to mitigate the detrimental impacts of ammonia stress on yellow catfish.

Toxicity of common biocides used in aquaculture to embryos and larvae of Brachymystax tsinlingensis Li.

Brachymystax tsinlingensis Li is a threatened fish species endemic to China. With the problems of environmental factors and seeding breeding diseases, it is important to further improve the efficiency of seeding breeding and the basis of resource protection. This study investigated the acute toxicity of copper, zinc and methylene blue (MB) on hatching, survival, morphology, heart rate (HR) and stress behaviour of B. tsinlingensis. Eggs (diameter: 3.86 ± 0.07 mm, weight: 0.032 ± 0.004 g) of B. tsinlingensis were selected randomly from artificial propagation and developed from eye-pigmentation-stage embryos to yolk-sac stage larvae (length: 12.40 ± 0.02 mm, weight: 0.03 ± 0.001 g) and exposed to different concentrations of Cu, Zn and MB for 144 h in a series of semi-static toxicity tests. The acute toxicity tests indicated that the 96-h median lethal concentration (LC50 ) values of the embryos and larvae were 1.71 and 0.22 mg l-1 for copper and 2.57 and 2.72 mg l-1 for zinc, respectively, whereas the MB LC50 after 144-h exposure for embryos and larvae were 67.88 and 17.81 mg l-1 , respectively. The safe concentrations of copper, zinc and MB were 0.17, 0.77 and 6.79 mg l-1 for embryos and 0.03, 0.03 and 1.78 mg l-1 for larvae, respectively. Copper, zinc and MB treatments with concentrations greater than 1.60, 2.00 and 60.00 mg l-1 , respectively, led to a significantly low hatching rate and significantly high embryo mortality (P < 0.05), and copper and MB treatments with concentrations greater than 0.2 and 20 mg l-1 led to significantly high larvae mortality (P < 0.05). Exposure to copper, zinc and MB resulted in developmental defects, including spinal curvature, tail deformity, vascular system anomalies and discolouration. Moreover, copper exposure significantly reduced the HR of larvae (P < 0.05). The embryos exhibited an obvious change in behaviour, converting from the normal behaviour of emerging from the membrane head first to emerging tail first, with probabilities of 34.82%, 14.81% and 49.07% under copper, zinc and MB treatments, respectively. The results demonstrated that the sensitivity of yolk-sac larvae to copper and MB was significantly higher than that of embryos (P < 0.05) and that B. tsinlingensis embryos or larvae might be more resistant to copper, zinc and MB than other members of the Salmonidae family, which benefits their resource protection and restoration.

Effects of ammonia and roxithromycin exposure on skin mucus microbiota composition and immune response of juvenile yellow catfish Pelteobagrus fulvidraco.

As an inevitable factor in aquaculture, ammonia plays a critical role in macrolide antibiotic resistance, leading to accumulating of antibiotic-resistant bacteria in fish skin mucus. In this study, four experimental groups were implemented to test the effects of ammonia alone or in combination with roxithromycin for 28 days on skin mucus microbial composition and the immune response of yellow catfish: CON (control), AN (50.00 mg L-1 total ammonia nitrogen, TA-N), ROX (100 µg L-1 roxithromycin), and HR (50.00 mg L-1 TA-N, 100 µg L-1 ROX). This study demonstrated that ammonia or roxithromycin exposure resulted in increased plasma ammonia content and decreased total antioxidant capacity. Compared with AN group, the combined exposure of ammonia and roxithromycin inhibited the skin mucus immune response. Microbial composition analysis showed that combined exposure of ammonia and roxithromycin had no significant effect on skin mucus α-diversity as compared with CON group. The abundance of Cetobacterium, Rhizobiales_Incertae_Sedis_uncultured and Acinetobacter was increased significantly with the combined effect of ammonia and roxithromycin, these bacteria may be potentially antibiotic-resistant. As compared with CON group, the combined exposure of ammonia and roxithromycin did not affect skin goblet cell counts. This study suggests that combined exposure to ammonia and ROX increases the risk of the emergence of antibiotic-resistant bacteria.

The Effect of Behavior Couples Therapy on Alcohol and Drug Use Disorder: a Systematic Review and Meta-Analysis.

AIMS: Behavior couples therapy (BCT) is widely considered to be effective in the treatment of substance use disorders. However, the effect size of BCT in different outcome measures, and at different time points requires further study to prove it. METHODS: Systematic searches were performed in various databases. Ultimately, we identified 12 studies, involving 19 randomized controlled trials. We used Hedges' g as the effect size, and all pooled analyses were performed using random-effects models. RESULTS: After treatment, BCT was superior to control conditions (either an active or inactive control group) in frequency of substance use (g = 0.17), substance use consequences (g = -0.28) and relationship satisfaction (g = 0.45). After a 12-month follow-up, BCT remained superior to control conditions in frequency of substance use (g = 0.32), substance use consequences (g = -0.34) and relationship satisfaction (g = 0.31). In addition, BCT was more effective in reducing the frequency of substance use than individual-based treatment (IBT) (g = 0.23). There was no significant relationship between the effect size of BCT and publication year (t = 0.92, P = 0.372), percentage of females (t = -0.02, P = 0.987) or the number of treatment sessions (t = -0.52, P = 0.609). CONCLUSIONS: BCT was superior to the control conditions in all three outcome measures after treatment and at follow-up, and showed a relatively large effect size for relationship satisfaction. Moreover, BCT was superior to IBT in reducing the frequency of substance use.

The argininosuccinate synthetase can differentially regulate nitric oxide synthase in yellow catfish Pelteobagrus fulvidraco.

Fish are at high risk of exposure to ammonia in aquaculture systems. When ammonia stress occurs, fish are more prone to disease outbreaks, but the mechanism is not very clear. The argininosuccinate synthetase (ASS) plays an important role in the regulation of urea synthesis and nitric oxide synthesis. We speculated that there must be some relationship between ASS expression and disease outbreak. In this study, ASS was cloned from the yellow catfish. The full-length cDNAs of ASS was 1558 bp, with open reading frames of 1236 bp. The mRNA expression of ASS gene was the highest in liver, kidney and brain. This study consists of two parts: 1) For ammonia challenge in vivo, yellow catfish (15.00 ± 1.50 g) were divided into control group, low ammonia group (1/10 96 h LC50), and high ammonia group (1/2 96 h LC50). The experiment continued for 192 h. The results showed that ammonia stress elevated serum ammonia content, and inhibited urea synthesis enzymes activities but up-regulated the expression levels of related genes except ARG, and induced arginine accumulation and nitric oxide synthase (nNOS and iNOS) different expression, and decreased resistance to Aeromonas hydrophage; 2) For ammonia challenge in vitro, the primary culture of liver cell was divided into four groups: control group, BPP group (Bj-BPP-10c was added as ASS activator), Amm group (96 h LC50), and Amm + BPP group. The experiment continued for 96 h. The results showed that the Bj-BPP-10c can inhibit nNOS activity and improve cell survival rate, and enhance iNOS activity and immune response (lysozyme, complement, respiratory burst, and phagocytic index) by activate ASS when ammonia stress occurred. Our results indicated that targeted regulation of ASS can improve iNOS activity, and enhance the immune response of yellow catfish under ammonia stress.

Glutamine synthetase (GS) deficiency can affect ammonia tolerance of yellow catfish Pelteobagrus fulvidraco.

Glutamine synthetase (GS) plays a crucial role in the regulation of glutamine synthesis in fish which is a very effective ammonia detoxification strategy. In this study, the full-length GS was cloned from the liver of yellow catfish. The full-length cDNA sequence of GS was 1928 bp in length and encoded 371 amino acids. The amino acid sequence of GS showed high homology (99%) with that of channel catfish. The highest mRNA expression of GS was found in the brain of yellow catfish. Acute ammonia stress (96 h LC50) significantly increased ammonia levels in plasma, liver, and brain, and GS gene expression was significantly up-regulated in the liver and brain. RNA interference inhibited the GS mRNA expression level in primary cultured hepatocytes after acute ammonia stress and reduced hepatocyte survival rate. It is suggested that GS plays a key role in ammonia detoxification in yellow catfish by regulating glutamine synthesis.

Ammonia induces changes in carbamoyl phosphate synthetase I and its regulation of glutamine synthesis and urea cycle in yellow catfish Pelteobagrus fulvidraco.

Fishes can adapt to certain levels of environmental ammonia in water, but the strategies utilized to defend against ammonia toxicity are not exactly the same. The carbamyl phosphate synthase I (CPS I) plays an important role in the regulation of glutamine synthesis and urea cycle, which are the most common strategies for ammonia detoxification. In this study, CPS I was cloned from the yellow catfish. The full-length cDNAs of the CPS I was 5 034 bp, with open reading frames of 4 461 bp. Primary amino acid sequence alignment of CPS I revealed conserved similarity between the functional domains of the yellow catfish CPS I protein with CPS I proteins of other animals. The mRNA expression of CPS I was significantly up-regulated in liver and kidney tissues after acute ammonia stress. The CPS I RNA interference (RNAi) down-regulated the mRNA expressions of CPS I and ornithine transcarbamylase (OTC), but up-regulated glutamine synthetase (GS) and glutamate dehydrogenase (GDH) expressions in primary culture of liver cell after acute ammonia stress. Similarly, the activity of enzymes related to urea cycle decreased significantly, while the activity of enzymes related to glutamine synthesis increased significantly. The results of RNAi in vitro suggested that when the urea cycle is disturbed, the glutamine synthesis will be activated to cope with ammonia toxicity.

The risk factors of the postoperative poor wound healing in spinal tuberculosis patients: A single centre retrospective cohort study.

The purpose of this study is to find out the risk factors of poor wound healing (PWH) in spinal tuberculosis (STB) patients. A total of 232 STB patients who underwent debridement surgery between January 2012 to June 2020 were included in this retrospective study. The study cohort was divided into two groups according to the presence or absence of PWH. The clinical characteristics of STB patients who developed PWH were evaluated, and risk factors were found using logistic regression analysis. Of the 232 patients, 30 developed PWH. Multivariate binary logistic regression analysis showed that pulmonary tuberculosis, long operation time and low postoperative albumin level were independent risk factors for PWH in STB patients. Receiver operating characteristic curve analysis showed that the optimal cutoff value of PWH in operation time and postoperative albumin are 200 minutes and 30 g/L, respectively. Pulmonary tuberculosis, long operation time and low postoperative albumin level are independent risk factors for PWH following surgery for STB. Curing pulmonary tuberculosis, controlling operation time and supervising postoperative serum albumin may decrease the risk of PWH among STB patients.

Depression and Osteoporosis: A Mendelian Randomization Study.

Observational studies suggest a link between depression and osteoporosis, but these may be subject to confounding and reverse causality. In this two-sample Mendelian randomization analysis, we included the large meta-analysis of genome-wide association studies for depression among 807,553 individuals (246,363 cases and 561,190 controls) of European descent, the large meta-analysis to identify genetic variants associated with femoral neck bone mineral density (FN-BMD), forearm BMD (FA-BMD) and lumbar spine BMD (LS-BMD) among 53,236 individuals of European ancestry, and the GWAS summary data of heel BMD (HE-BMD) and fracture among 426,824 individuals of European ancestry. The results revealed that genetic predisposition towards depression showed no causal effect on FA-BMD (beta-estimate: 0.091, 95% confidence interval [CI] - 0.088 to 0.269, SE:0.091, P value = 0.320), FN-BMD (beta-estimate: 0.066, 95% CI - 0.016 to 0.148, SE:0.042, P value = 0.113), LS-BMD (beta-estimate: 0.074, 95% CI - 0.029 to 0.177, SE:0.052, P value = 0.159), HE-BMD (beta-estimate: 0.009, 95% CI - 0.043 to 0.061, SE:0.027, P value = 0.727), or fracture (beta-estimate: 0.008, 95% CI - 0.071 to 0.087, SE:0.041, P value = 0.844). These results were also confirmed by multiple sensitivity analyses. Contrary to the findings of observational studies, our results do not reveal a causal role of depression in osteoporosis or fracture.

Arginase plays an important role in ammonia detoxification of yellow catfish Pelteobagrus fulvidraco.

A two-stage study was carried out to test the mechanism of arginase in ammonia detoxification of yellow catfish. At stage 1, fish was injected lethal half concentration ammonium acetate and 0.9% sodium chloride respectively every 12 h in six replicates for 72 h. The result found that no significant different in serum ammonia contents of fish in ammonium acetate group at hours 12, 24, 36, 48, 60 and 72. At stage 2, ammonium acetate group was split in two, one continued to injected with ammonium acetate (NH3 group) and the other with ammonium acetate and valine (an inhibitor of arginase; Val group); Sodium chloride group also was split in two, one continued to injected with sodium chloride (NaCl group) and the other with sodium chloride and valine (NaCl + Val group). The experiment continued for 12 h. Serum ammonia and liver arginine contents of fish in Val group were higher than those of fish in NH3 group; Compared with NaCl group, arginase activity and ARG 1 expression in liver of fish in Val group were lower; Fish in NaCl and NaCl + Val groups had the lowest serum superoxide dismutase activities, malondialdehyde, tumor necrosis factor-α, interleukin 1 and 8 contents, TNF-α, IL-1 and IL-8 expressions than fish in NH3 and Val groups, and had the higher lysozyme activities, complement 3 and 4 contents. This study indicates that ammonia poisoning would lead to oxidative damage, immunosuppression and inflammation in yellow catfish; Arginase may be an important target of ammonia toxicity in yellow catfish; Exogenous arginine supplementation might alleviate the symptoms of ammonia poisoning in yellow catfish.

Targeting GRP78 enhances the sensitivity of HOS osteosarcoma cells to pyropheophorbide-α methyl ester-mediated photodynamic therapy via the Wnt/ß-catenin signaling pathway.

Photodynamic therapy (PDT), which is a new method for treating tumors, has been used in the treatment of cancer. In-depth research has shown that PDT cannot completely kill tumor cells, indicating that tumor cells are resistant to PDT. Glucose regulatory protein 78 (GRP78), which is a key regulator of endoplasmic reticulum stress, has been confirmed to be related to tumor resistance and recurrence, but there are relatively few studies on the further mechanism of GRP78 in PDT. Our experiment aimed to observe the role of GRP78 in HOS human osteosarcoma cells treated with pyropheophorbide-α methyl ester-mediated photodynamic therapy (MPPα-PDT) and to explore the possible mechanism by which the silencing of GRP78 expression enhances the sensitivity of HOS osteosarcoma cells to MPPα-PDT. HOS osteosarcoma cells were transfected with siRNA-GRP78. Apoptosis and reactive oxygen species (ROS) levels were detected by Hoechst staining and flow cytometry, cell viability was detected by Cell Counting Kit-8 assay, GRP78 protein fluorescence intensity was detected by immunofluorescence, and apoptosis-related proteins, cell proliferation-related proteins, and Wnt pathway-related proteins were detected by western blot. The results showed that MPPα-PDT can induce HOS cell apoptosis and increase GRP78 expression. After successful siRNA-GRP78 transfection, HOS cell proliferation was decreased, and apoptosis-related proteins expressions was increased, Wnt/ß-catenin-related proteins expressions was decreased, and ROS levels was increased. In summary, siRNA-GRP78 enhances the sensitivity of HOS cells to MPPα-PDT, the mechanism may be related to inhibiting Wnt pathway activation and increasing ROS levels.

Ammonia stress disrupts intestinal microbial community and amino acid metabolism of juvenile yellow catfish (Pelteobagrus fulvidraco).

Ammonia has adverse effects on aquatic animals, which is also widely distributed in natural aquatic environments and intensive aquaculture systems. The intestine is a primary defensive line for aquatic animals, the accumulation of ammonia in the aquatic environment can cause irreversible damage to intestinal function. In this study, we investigated the effects of acute ammonia stress on the reaction characteristics of digestive function, amino acid metabolism, and the variation in the intestinal microbiota of juvenile yellow catfish (Pelteobagrus fulvidraco). Thus, the yellow catfish was placed in water with the addition of ammonia at 0 (control), 14.6, and 146 mg/L total ammonia nitrogen for 96-h. The present study observed that ammonia accumulated in the intestine and muscle (ammonia contents in the intestine and muscle increased) and induced the activities of protein digestive enzymes dysfunction (pepsin increased while trypsin decreased). Ammonia stress changed various amino acids composition (proline, arginine, lysine, histidine, phenylalanine, tyrosine, leucine, isoleucine, valine, alanine, glutamic acid, tyrosine, and aspartic acid contents were increased in muscle) and increased the activities of alanine aminotransferase and aspartate aminotransferase in muscle. Furthermore, through 16 S rRNA gene analysis, ammonia stress-induced reduction in diversity, richness, and evenness and structure of microbiota alteration in the intestine. At the phylum level, the abundance of Fusobacteria increased while Firmicutes and Actinobacteria decreased significantly. At the genus level, the abundance of beneficial microbiota Cetobacterium significantly increased after ammonia stress. In conclusion, activation of amino acid synthesis in muscle may be involved in ammonia detoxification after severe ammonia stress. The accumulation of ammonia can disrupt the intestinal digestive function and intestinal microbiota community. The Cetobacterium may be a new potential positive factor in the resistance of ammonia toxicity.

Ammonia toxicity in the yellow catfish (Pelteobagrus fulvidraco): The mechanistic insight from physiological detoxification to poisoning.

Ammonia is toxic to fishes. Different fish have different defense strategies against ammonia, so the mechanism of ammonia poisoning is different. In this study, yellow catfish were exposed to three levels of ammonia (0, 5.70 and 57.00 mg L-1) for 96 h. The results showed that ammonia poisoning could lead to free amino acid imbalance (ornithine and citrulline contents declined; arginine content elevated), urea cycle enzymes deficiency (carbamyl phosphate synthetase and arginase contents declined), oxidative stress (superoxide dismutase, catalase and glutathione peroxidase activities declined), immunosuppression (lysozyme activity, 50% hemolytic complement and total immunoglobulin contents and phagocytic index declined) and cytokines release (TNF, IL 1 and IL 8 contents elevated). In addition, ammonia poisoning could induce up-regulation of antioxidant enzymes (Cu/Zn-SOD, Mn-SOD, CAT and GPx), cytokines (TNFα, IL 1 and IL 8) and apoptosis (p53, Bax, cytochrome c, Caspase 3 and Caspase 9) genes transcription. This study suggesting that the urea cycle and glutamine synthesis both were involved in the ammonia detoxification of yellow catfish, and the immunosuppression, inflammation and apoptotic induced by ammonia poisoning in yellow catfish are related to oxidative stress.

The protective effects of selenium on chronic ammonia toxicity in yellow catfish (Pelteobagrus fulvidraco).

Ammonia is toxic to most fish, and its negative effects can be eliminated by nutritional manipulation. In this study, triplicate groups of yellow catfish (0.58 ± 0.03 g) were fed diets supplemented with 0, 0.30 and 0.60 mg selenium (Se) kg-1 diet for 56 days under three ammonia contents (0.00, 5.70 and 11.40 mg L-1 total ammonia nitrogen). The results showed that ammonia toxicity could affects growth (weight gain, feed efficiency ratio, Se contents in muscle and whole body declined) and survival, leads to oxidative stress (total antioxidant capacity, superoxide dismutase, catalase and glutathione peroxidase activities declined and malondialdehyde accumulation), immunosuppression (lysozyme activity, 50% hemolytic complement, immunoglobulin M, respiratory burst and phagocytic index declined) and cytokines release (TNF, IL 1 and IL 8 elevated), induces up-regulation of antioxidant enzymes (Cu/Zn-SOD, Mn-SOD, CAT and GPx), cytokines (TNFα, IL 1 and IL 8) and pro-apoptotic genes (p53, Bax, Cytochrome c, Caspase 3 and Caspase 9) transcription, and down-regulation of anti-apoptotic gene Bcl2 transcription. The dietary Se supplementation could mitigate the adverse effect of ammonia poisoning on fish growth, oxidative damage, immunosuppression and apoptotic.

Modulation of lipid metabolism in juvenile yellow catfish (Pelteobagrus fulvidraco) as affected by feeding frequency and environmental ammonia.

In the intensive culture systems, excessive feeding leads to ammonia accumulation, which results in lipid metabolism disorder. However, little information is available on the modulation of lipid metabolism in fish as affected by feeding frequency and ammonia stress. In this study, weight gain increased as feeding frequency increased from one to four times daily, but feed conversion ratio is opposite. The highest survival was found in ammonia group when fish was fed two times daily. Liver ammonia content increased as feeding frequency increased from one to four times daily, and the highest brain ammonia content was found when fish was fed four times daily. The highest liver 6-phospho-gluconate dehydrogenase (6PGD), fatty acid synthase (FAS), carnitine palmitoyltransferase (CPT), and lipoprotein lipase (LPL) contents were found in control group when fish was fed four times daily; in comparison, the highest liver 6PGD, FAS, CPT, and LPL contents were found in ammonia group when fish was fed two times daily. Liver 6PGD, FAS, CPT 1, SREBP-1, and PPARα mRNA expression in control group increased significantly as feeding frequency increased from one to four times daily, and the highest expression of 6PGD, G6PD, and FAS was observed in ammonia group when fish was fed two times daily. This study indicated that the optimal feeding frequency is two times daily when yellow catfish exposed to ammonia.

Effects of acute ammonia toxicity on oxidative stress, immune response and apoptosis of juvenile yellow catfish Pelteobagrus fulvidraco and the mitigation of exogenous taurine.

Ammonia can easily form in intensive culture systems due to ammonification of uneaten food and animal excretion, which usually brings detrimental health effects to fish. However, little information is available on the mechanisms of the detrimental effects of ammonia stress and mitigate means in fish. In this study, the four experimental groups were carried out to test the response of yellow catfish to ammonia toxicity and their mitigation through taurine: group 1 was injected with NaCl, group 2 was injected with ammonium acetate, group 3 was injected with ammonium acetate and taurine, and group 4 was injected taurine. The results showed that ammonia poisoning could induce ammonia, glutamine, glutamate and malondialdehyde accumulation, and subsequently lead to blood deterioration (red blood cell, hemoglobin and serum biochemical index reduced), oxidative stress (superoxide dismutase and catalase activities declined) and immunosuppression (lysozyme, 50% hemolytic complement, total immunoglobulin, phagocytic index and respiratory burst reduced), but the exogenous taurine could mitigate the adverse effect of ammonia poisoning. In addition, ammonia poisoning could induce up-regulation of antioxidant enzymes (Cu/Zn-SOD, CAT, GPx and GR), inflammatory cytokines (TNF, IL-1 and IL-8) and apoptosis (p53, Bax, caspase 3 and caspase 9) genes transcription, suggesting that cell apoptotic and inflammation may relate to oxidative stress. This result will be helpful to understand the mechanism of aquatic toxicology induced by ammonia in fish.

Self-renewal of hepatoblasts under chemically defined conditions by iterative growth factor and chemical screening.

UNLABELLED: Tissue-specific stem/progenitor cells are essential to mediate organogenesis and tissue homeostasis. In addition, these cells have attracted significant interest for their therapeutic potential. However, it remains challenging to expand most types of these cells in vitro. In this study we devised a screening strategy aimed at identifying growth factors and small molecules that can sustain self-renewal of mouse hepatoblasts. This approach began with a defined basal condition, on top of which collections of growth factors and bioactive small molecules were screened for maintaining self-renewal of primary hepatoblasts. The initially identified proteins and small molecules were then combined in the basal media for subsequent screening to identify additional molecules that can synergistically promote hepatoblast self-renewal. This strategy was performed iteratively to eventually define a small molecule and growth factor cocktail, including epidermal growth factor, glycogen synthase kinase 3 inhibitor, transforming growth factor ß receptor inhibitor, lysophosphatidic acid, and sphingosine 1-phosphate, which was sufficient to sustain long-term self-renewal of the murine hepatoblasts under chemically defined conditions. These expanded hepatoblasts retain the ability to respond to liver developmental cues and produce functional hepatocytes and form bile duct-like structures. CONCLUSION: Our work established a chemically defined condition that allows long-term expansion of hepatoblasts, improved our understanding of hepatoblast self-renewal, and highlights the power of phenotypic screening to enable self-renewal of somatic stem/progenitor cells.

The SLC38A9-mTOR axis is involved in autophagy in the juvenile yellow catfish (Pelteobagrus fulvidraco) under ammonia stress.

The primary objective of this study was to examine the effect of acute ammonia stress on hepatic physiological alterations in yellow catfish by performing a comprehensive analysis of the metabolome and transcriptome. The present study showed that ammonia stress led to liver metabolic disruption, functional incapacitation, and oxidative damage. Transcriptomic and metabolomic analyses revealed transcriptional and metabolic differences in the liver of yellow catfish under control and high ammonia stress conditions. After 96 h of acute exposure to ammonia, the mRNA levels of 596 liver genes were upregulated, whereas those of 603 genes were downregulated. Enrichment analysis of the differentially expressed genes identified multiple signalling pathways associated with autophagy, including the endocytosis, autophagy-animal, and mammalian target of rapamycin signalling pathways. A total of 186 upregulated and 117 downregulated metabolites, primarily associated with amino acid biosynthesis pathways, were identified. Multi-omics integration revealed the solute carrier family 38 member 9 (SLC38A9)-mammalian target of rapamycin axis as a signalling nexus for amino acid-mediated modulation of autophagy flux, and q-PCR was used to assess the expression of autophagy-related genes (LC3a and sqstm1), revealing an initial inhibition followed by the restoration of autophagic flux during ammonia stress. Subsequent utilisation of arginine as a specific SLC38A9 activator during ammonia stress demonstrated that augmented SLC38A9 expression hindered autophagy, exacerbated ammonia toxicity, and caused a physiological decline (total cholesterol, total triglyceride, acid phosphatase, alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase levels were significantly increased), oxidative stress, and apoptosis. Autophagy activation may be an adaptive mechanism to resist ammonia stress.

Proteomic Analysis of Collagen: a Mass Spectrometry Approach to Material Identification of Shadow Puppet Cultural Relics.

Shadow puppets are a popular art form in various regions, including China, Indonesia, and Turkey, and are rich in cultural significance. However, there is a considerable lack of research on the materials, diseases and conservation techniques related to shadow puppet relics. Material identification is the basis for understanding the production process of ancient shadow puppet relics and evaluating their deterioration degree. The microscopic morphology and infrared spectroscopy results in our experiments showed that the traditional methods of ancient skin identification were not effective in the shadow puppet samples. In order to achieve accurate identification, we used biological mass-spectrometry in proteomics to examine two puppet relics and commercially available modern shadow puppets. The results showed that the above samples could be detected by mass spectrometry with abundant peptides, including peptides specific for bovine skin. These peptides cannot be found in other commonly used materials for making shadow puppets, including the skins of pig, sheep, deer and horse. It is worth mentioning that we have found the peptides specific to yellow cowhide in two ancient shadow puppet relics samples. Therefore, the proteomic evidence shows that the raw materials of the two shadow puppet relics samples are yellow cowhide. Four modern samples also confirmed the reliability of material identification using proteomics. The proteomic evidence shows that the biological mass spectrometry will contribute to the scientific research of shadow puppet relics and other skin and leather cultural relics.