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1.
Molecules ; 29(5)2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38474529

ABSTRACT

As a crucial enzyme for cellulose degradation, ß-glucosidase finds extensive applications in food, feed, and bioethanol production; however, its potential is often limited by inadequate thermal stability and glucose tolerance. In this study, a functional gene (lq-bg5) for a GH1 family ß-glucosidase was obtained from the metagenomic DNA of a hot spring sediment sample and heterologously expressed in E. coli and the recombinant enzyme was purified and characterized. The optimal temperature and pH of LQ-BG5 were 55 °C and 4.6, respectively. The relative residual activity of LQ-BG5 exceeded 90% at 55 °C for 9 h and 60 °C for 6 h and remained above 100% after incubation at pH 5.0-10.0 for 12 h. More importantly, LQ-BG5 demonstrated exceptional glucose tolerance with more than 40% activity remaining even at high glucose concentrations of 3000 mM. Thus, LQ-BG5 represents a thermophilic ß-glucosidase exhibiting excellent thermal stability and remarkable glucose tolerance, making it highly promising for lignocellulose development and utilization.


Subject(s)
Glucose , Hot Springs , Glucose/metabolism , beta-Glucosidase/metabolism , Escherichia coli/metabolism , Temperature , Hydrogen-Ion Concentration , Enzyme Stability , Substrate Specificity
2.
Int J Mol Sci ; 24(10)2023 May 10.
Article in English | MEDLINE | ID: mdl-37239878

ABSTRACT

The modern biotechnology industry has a demand for macromolecules that can function in extreme environments. One example is cold-adapted proteases, possessing advantages such as maintaining high catalytic efficiency at low temperature and low energy input during production and inactivation. Meanwhile, cold-adapted proteases are characterised by sustainability, environmental protection, and energy conservation; therefore, they hold significant economic and ecological value regarding resource utilisation and the global biogeochemical cycle. Recently, the development and application of cold-adapted proteases have gained gaining increasing attention; however, their applications potential has not yet been fully developed, which has seriously restricted the promotion and application of cold-adapted proteases in the industry. This article introduces the source, related enzymology characteristics, cold resistance mechanism, and the structure-function relationship of cold-adapted proteases in detail. This is in addition to discussing related biotechnologies to improve stability, emphasise application potential in clinical medical research, and the constraints of the further developing of cold-adapted proteases. This article provides a reference for future research and the development of cold-adapted proteases.


Subject(s)
Biotechnology , Peptide Hydrolases , Peptide Hydrolases/chemistry , Endopeptidases , Catalysis , Cold Temperature
3.
BMC Vet Res ; 18(1): 347, 2022 Sep 15.
Article in English | MEDLINE | ID: mdl-36109808

ABSTRACT

BACKGROUND: Cottonseed meal (CSM), a relatively rich source of protein and amino acids, is used as an inexpensive alternative to soybean meal (SBM) in poultry diets. However, the toxicity of free gossypol in CSM has been a primary concern. The present study was conducted to investigate the effects of CSM on growth performance, serum biochemical parameters, and liver redox status in goslings at 1 to 28 days of age. Three hundred 1-day-old male goslings were randomly divided into 5 groups (10 goslings/pen, 6 replicate pens/group) and subjected to a 28-day experiment. Five isonitrogenous and isoenergetic diets were formulated such that 0% (control), 25% (CSM25), 50% (CSM50), 75% (CSM75), and 100% (CSM100) of protein from SBM was replaced by protein from CSM. The free gossypol contents in the five diets were 0, 56, 109, 166, and 222 mg/kg, respectively. RESULTS: The results showed that dietary CSM was associated with linear decreases in body weight, average daily feed intake and average daily gain and linear increases in the feed-to-gain ratio from 1 to 28 days of age (P < 0.001). As the dietary CSM concentration increased, a numerical increase was found in the mortality of goslings. According to a single-slope broken-line model, the breakpoints for the average daily gain of dietary free gossypol concentration on days 1 to 14, 15 to 28, and 1 to 28 occurred at 23.63, 14.78, and 18.53 mg/kg, respectively. As the dietary CSM concentration increased, serum albumin (P < 0.001) concentrations decreased linearly and serum uric acid (P = 0.011) increased linearly. The hydroxyl radical scavenging ability (P = 0.002) and catalase (P < 0.001) and glutathione peroxidase (P = 0.001) activities of the liver decreased linearly with increasing dietary CSM. However, dietary CSM did not affect the concentrations of reactive oxygen metabolites, malondialdehyde, or protein carbonyl in the liver. CONCLUSIONS: The increasing dietary CSM increased the concentration of free gossypol and altered the composition of some amino acids in the diet. A high concentration of CSM reduced the growth performance of goslings aged 1 to 28 days by decreasing feed intake, liver metabolism, and antioxidant capacity. From the primary concern of free gossypol in CSM, the tolerance of goslings to free gossypol from CSM is low, and the toxicity of free gossypol has a cumulative effect over time.


Subject(s)
Cottonseed Oil , Gossypol , Amino Acids/metabolism , Animal Feed/analysis , Animals , Antioxidants/metabolism , Catalase , Cottonseed Oil/analysis , Cottonseed Oil/metabolism , Cottonseed Oil/pharmacology , Geese/metabolism , Glutathione Peroxidase , Gossypol/analysis , Gossypol/metabolism , Gossypol/pharmacology , Hydroxyl Radical/analysis , Hydroxyl Radical/metabolism , Hydroxyl Radical/pharmacology , Liver/metabolism , Male , Malondialdehyde/metabolism , Oxidation-Reduction , Oxygen/metabolism , Serum Albumin/analysis , Glycine max/metabolism , Uric Acid/analysis
4.
J Autoimmun ; 100: 62-74, 2019 06.
Article in English | MEDLINE | ID: mdl-30879886

ABSTRACT

Cytokine storm syndrome (CSS) is a life-threatening condition characterized by excessive activation of T cells and uncontrolled inflammation, mostly described in patients with familial hemophagocytic lymphohistiocytosis and certain systemic auto-inflammatory diseases, such as systemic juvenile idiopathic arthritis (sJIA). Defects in T cell cytotoxicity as a mechanism for uncontrolled inflammation following viral infections fail to represent the whole spectrum of CSS. Evidence implicates dysregulated innate immune responses, especially activation of monocytes and macrophages, in patients with CSS. However, the direct contribution of monocytes/macrophages to CSS development and the signaling pathways involved in their activation have not been formally investigated. We find that depletion of monocytes/macrophages during early stages of CSS development, by clodronate-liposomes or neutralizing anti-CSF1 antibody, reduces mortality and inflammatory cytokine levels in two CSS mouse models, one dependent on T cells and the second induced by repeated TLR9 stimulation. We further demonstrate that activation of Plcγ2 in myeloid cells controls CSS development by driving macrophage pro-inflammatory responses. Intriguingly, the Plcγ2 downstream effector Tmem178, a negative modulator of calcium levels, acts in a negative feedback loop to restrain inflammatory cytokine production. Genetic deletion of Tmem178 leads to pro-inflammatory macrophage polarization in vitro and more severe CSS in vivo. Importantly, Tmem178 levels are reduced in macrophages from mice with CSS and after exposure to plasma from sJIA patients with active disease. Our data identify a novel Plcγ2/Tmem178 axis as a modulator of inflammatory cytokine production by monocytes/macrophages. We also find that loss of Tmem178 accentuates the pro-inflammatory responses in CSS.


Subject(s)
Macrophage Activation Syndrome/immunology , Macrophages/immunology , Membrane Proteins/immunology , Monocytes/immunology , Phospholipase C gamma/immunology , Signal Transduction/immunology , Animals , Humans , Macrophage Activation Syndrome/genetics , Macrophage Activation Syndrome/pathology , Macrophages/pathology , Membrane Proteins/genetics , Mice , Mice, Knockout , Monocytes/pathology , Phospholipase C gamma/genetics , Signal Transduction/genetics
5.
J Autoimmun ; 101: 94-108, 2019 07.
Article in English | MEDLINE | ID: mdl-31018906

ABSTRACT

Store-operated calcium entry (SOCE) modulates cytosolic calcium in multiple cells. Endoplasmic reticulum (ER)-localized STIM1 and plasma membrane (PM)-localized ORAI1 are two main components of SOCE. STIM1:ORAI1 association requires STIM1 oligomerization, its re-distribution to ER-PM junctions, and puncta formation. However, little is known about the negative regulation of these steps to prevent calcium overload. Here, we identified Tmem178 as a negative modulator of STIM1 puncta formation in myeloid cells. Using site-directed mutagenesis, co-immunoprecipitation assays and FRET imaging, we determined that Tmem178:STIM1 association occurs via their transmembrane motifs. Mutants that increase Tmem178:STIM1 association reduce STIM1 puncta formation, SOCE activation, impair inflammatory cytokine production in macrophages and osteoclastogenesis. Mutants that reduce Tmem178:STIM1 association reverse these effects. Furthermore, exposure to plasma from arthritic patients decreases Tmem178 expression, enhances SOCE activation and cytoplasmic calcium. In conclusion, Tmem178 modulates the rate-limiting step of STIM1 puncta formation and therefore controls SOCE in inflammatory conditions.


Subject(s)
Calcium/metabolism , Intracellular Calcium-Sensing Proteins/metabolism , Membrane Proteins/metabolism , Myeloid Cells/metabolism , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Stromal Interaction Molecule 1/genetics , Stromal Interaction Molecule 1/metabolism , Animals , Endoplasmic Reticulum/metabolism , Female , Gene Expression Regulation , HEK293 Cells , Humans , Macrophage Activation/immunology , Macrophages/immunology , Macrophages/metabolism , Male , Mice , Myeloid Cells/immunology , Neoplasm Proteins/chemistry , Osteogenesis/genetics , Protein Binding , Protein Interaction Domains and Motifs , Stromal Interaction Molecule 1/chemistry
6.
FASEB J ; 32(5): 2422-2437, 2018 05.
Article in English | MEDLINE | ID: mdl-29269400

ABSTRACT

The fourth member of the leucine-rich repeat-containing GPCR family (LGR4, frequently referred to as GPR48) and its cognate ligands, R-spondins (RSPOs) play crucial roles in the development of multiple organs as well as the survival of adult stem cells by activation of canonical Wnt signaling. Wnt/ß-catenin signaling acts to regulate breast cancer; however, the molecular mechanisms determining its spatiotemporal regulation are largely unknown. In this study, we identified LGR4 as a master controller of Wnt/ß-catenin signaling-mediated breast cancer tumorigenesis, metastasis, and cancer stem cell (CSC) maintenance. LGR4 expression in breast tumors correlated with poor prognosis. Either Lgr4 haploinsufficiency or mammary-specific deletion inhibited mouse mammary tumor virus (MMTV)- PyMT- and MMTV- Wnt1-driven mammary tumorigenesis and metastasis. Moreover, LGR4 down-regulation decreased in vitro migration and in vivo xenograft tumor growth and lung metastasis. Furthermore, Lgr4 deletion in MMTV- Wnt1 tumor cells or knockdown in human breast cancer cells decreased the number of functional CSCs by ∼90%. Canonical Wnt signaling was impaired in LGR4-deficient breast cancer cells, and LGR4 knockdown resulted in increased E-cadherin and decreased expression of N-cadherin and snail transcription factor -2 ( SNAI2) (also called SLUG), implicating LGR4 in regulation of epithelial-mesenchymal transition. Our findings support a crucial role of the Wnt signaling component LGR4 in breast cancer initiation, metastasis, and breast CSCs.-Yue, Z., Yuan, Z., Zeng, L., Wang, Y., Lai, L., Li, J., Sun, P., Xue, X., Qi, J., Yang, Z., Zheng, Y., Fang, Y., Li, D., Siwko, S., Li, Y., Luo, J., Liu, M. LGR4 modulates breast cancer initiation, metastasis, and cancer stem cells.


Subject(s)
Breast Neoplasms/metabolism , Gene Expression Regulation, Neoplastic , Mammary Neoplasms, Animal/metabolism , Neoplasm Proteins/metabolism , Neoplastic Stem Cells/metabolism , Receptors, G-Protein-Coupled/biosynthesis , Wnt Signaling Pathway , Animals , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Line, Tumor , Female , Heterografts , Mammary Neoplasms, Animal/genetics , Mammary Neoplasms, Animal/pathology , Mice , Mice, Knockout , Mice, Nude , Neoplasm Metastasis , Neoplasm Proteins/genetics , Neoplasm Transplantation , Neoplastic Stem Cells/pathology , Receptors, G-Protein-Coupled/genetics
7.
J Biol Chem ; 292(4): 1178-1186, 2017 01 27.
Article in English | MEDLINE | ID: mdl-27941021

ABSTRACT

Phospholipases Cγ (PLCγ) 1 and 2 are a class of highly homologous enzymes modulating a variety of cellular pathways through production of inositol 1,4,5-trisphosphate and diacylglycerol (DAG). Our previous studies demonstrated the importance of PLCγ2 in osteoclast (OC) differentiation by modulating inositol 1,4,5-trisphosphate-mediated calcium oscillations and the up-regulation of the transcription factor NFATc1. Surprisingly, despite being expressed throughout osteoclastogenesis, PLCγ1 did not compensate for PLCγ2 deficiency. Because both isoforms are activated during osteoclastogenesis, it is plausible that PLCγ1 modulates OC development independently of PLCγ2. Here, we utilized PLCγ1-specific shRNAs to delete PLCγ1 in OC precursors derived from wild type (WT) mice. Differently from PLCγ2, we found that PLCγ1 shRNA significantly suppresses OC differentiation by limiting colony-stimulating factor 1 (CSF-1)-dependent proliferation and ß-catenin/cyclinD1 levels. Confirming the specificity toward CSF-1 signaling, PLCγ1 is recruited to the CSF-1 receptor following exposure to the cytokine. To understand how PLCγ1 controls cell proliferation, we turned to its downstream effector, DAG. By utilizing cells lacking the DAG kinase ζ, which have increased DAG levels, we demonstrate that DAG modulates CSF-1-dependent proliferation and ß-catenin/cyclinD1 levels in OC precursors. Most importantly, the proliferation and osteoclastogenesis defects observed in the absence of PLCγ1 are normalized in PLCγ1/DAG kinase ζ double null cells. Taken together, our study shows that PLCγ1 controls OC numbers via a CSF-1-dependent DAG/ß-catenin/cyclinD1 pathway.


Subject(s)
Cyclin D1/metabolism , Diglycerides/metabolism , Macrophage Colony-Stimulating Factor/metabolism , Osteoclasts/metabolism , Phospholipase C gamma/metabolism , Signal Transduction/physiology , beta Catenin/metabolism , Animals , Cell Proliferation/drug effects , Cell Proliferation/physiology , Cells, Cultured , Cyclin D1/genetics , Diacylglycerol Kinase/genetics , Diacylglycerol Kinase/metabolism , Diglycerides/genetics , Gene Knockdown Techniques , Macrophage Colony-Stimulating Factor/pharmacology , Mice , Osteoclasts/cytology , Phospholipase C gamma/genetics , Signal Transduction/drug effects , beta Catenin/genetics
8.
Proc Natl Acad Sci U S A ; 112(51): 15654-9, 2015 Dec 22.
Article in English | MEDLINE | ID: mdl-26644563

ABSTRACT

Phospholipase C gamma-2 (PLCγ2)-dependent calcium (Ca(2+)) oscillations are indispensable for nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1) activation and downstream gene transcription driving osteoclastogenesis during skeletal remodeling and pathological bone loss. Here we describe, to our knowledge, the first known function of transmembrane protein 178 (Tmem178), a PLCγ2 downstream target gene, as a critical modulator of the NFATc1 axis. In surprising contrast to the osteopetrotic phenotype of PLCγ2(-/-) mice, Tmem178(-/-) mice are osteopenic in basal conditions and are more susceptible to inflammatory bone loss, owing to enhanced osteoclast formation. Mechanistically, Tmem178 localizes to the ER membrane and regulates RANKL-induced Ca(2+) fluxes, thus controlling NFATc1 induction. Importantly, down-regulation of Tmem178 is observed in human CD14(+) monocytes exposed to plasma from systemic juvenile idiopathic arthritis patients. Similar to the mouse model, reduced Tmem178 expression in human cells correlates with excessive osteoclastogenesis. In sum, these findings identify an essential role for Tmem178 to maintain skeletal mass and limit pathological bone loss.


Subject(s)
Feedback, Physiological , Membrane Proteins/physiology , NFATC Transcription Factors/physiology , Osteoclasts/physiology , Osteogenesis , Animals , Calcium/metabolism , Cells, Cultured , Endoplasmic Reticulum/metabolism , Humans , Mice , Mice, Inbred C57BL , Monocytes/metabolism , Phospholipase C gamma/physiology
9.
J Biol Chem ; 290(4): 2455-65, 2015 Jan 23.
Article in English | MEDLINE | ID: mdl-25480784

ABSTRACT

Leucine-rich repeat G-protein-coupled receptors (LGRs) are a unique class of G-protein-coupled receptors characterized by a large extracellular domain to recognize ligands and regulate many important developmental processes. Among the three groups of LGRs, group B members (LGR4-6) recognize R-spondin family proteins (Rspo1-4) to stimulate Wnt signaling. In this study, we successfully utilized the "hybrid leucine-rich repeat technique," which fused LGR4 with the hagfish VLR protein, to obtain two recombinant human LGR4 proteins, LGR415 and LGR49. We determined the crystal structures of ligand-free LGR415 and the LGR49-Rspo1 complex. LGR4 exhibits a twisted horseshoe-like structure. Rspo1 adopts a flat and ß-fold architecture and is bound in the concave surface of LGR4 in the complex through electrostatic and hydrophobic interactions. All the Rspo1-binding residues are conserved in LGR4-6, suggesting that LGR4-6 bind R-spondins through an identical surface. Structural analysis of our LGR4-Rspo1 complex with the previously determined LGR4 and LGR5 structures revealed that the concave surface of LGR4 is the sole binding site for R-spondins, suggesting a one-site binding model of LGR4-6 in ligand recognition. The molecular mechanism of LGR4-6 is distinct from the two-step mechanism of group A receptors LGR1-3 and the multiple-interface binding model of group C receptors LGR7-8, suggesting LGRs utilize the divergent mechanisms for ligand recognition. Our structures, together with previous reports, provide a comprehensive understanding of the ligand recognition by LGRs.


Subject(s)
Receptors, G-Protein-Coupled/chemistry , Thrombospondins/chemistry , Amino Acid Sequence , Binding Sites , Crystallography, X-Ray , Drug Design , Gene Expression Regulation, Developmental , Humans , Leucine/chemistry , Ligands , Molecular Sequence Data , Mutagenesis , Plasmids , Protein Binding , Protein Multimerization , Protein Structure, Tertiary , Recombinant Proteins/chemistry , Sequence Homology, Amino Acid , Stem Cells/cytology , Wnt Proteins/metabolism
10.
Virol Sin ; 39(1): 81-96, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38042371

ABSTRACT

The mortality of patients with severe pneumonia caused by H1N1 infection is closely related to viral replication and cytokine storm. However, the specific mechanisms triggering virus replication and cytokine storm are still not fully elucidated. Here, we identified hypoxia inducible factor-1α (HIF-1α) as one of the major host molecules that facilitates H1N1 virus replication followed by cytokine storm in alveolar epithelial cells. Specifically, HIF-1α protein expression is upregulated after H1N1 infection. Deficiency of HIF-1α attenuates pulmonary injury, viral replication and cytokine storm in vivo. In addition, viral replication and cytokine storm were inhibited after HIF-1α knockdown in vitro. Mechanistically, the invasion of H1N1 virus into alveolar epithelial cells leads to a shift in glucose metabolism to glycolysis, with rapid production of ATP and lactate. Inhibition of glycolysis significantly suppresses viral replication and inflammatory responses. Further analysis revealed that H1N1-induced HIF-1α can promote the expression of hexokinase 2 (HK2), the key enzyme of glycolysis, and then not only provide energy for the rapid replication of H1N1 virus but also produce lactate, which reduces the accumulation of the MAVS/RIG-I complex and inhibits IFN-α/ß production. In conclusion, this study demonstrated that the upregulation of HIF-1α by H1N1 infection augments viral replication and cytokine storm by cellular metabolic reprogramming toward glycolysis mainly through upregulation of HK2, providing a theoretical basis for finding potential targets for the treatment of severe pneumonia caused by H1N1 infection.


Subject(s)
Influenza A Virus, H1N1 Subtype , Humans , Cytokine Release Syndrome , Metabolic Reprogramming , Virus Replication , Lactates
11.
Innovation (Camb) ; 5(3): 100599, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38510071

ABSTRACT

Elucidating the temporal process of immune remodeling under immunosuppressive treatment after liver transplantation (LT) is critical for precise clinical management strategies. Here, we performed a single-cell multi-omics analysis of peripheral blood mononuclear cells (PBMCs) collected from LT patients (with and without acute cellular rejection [ACR]) at 13 time points. Validation was performed in two independent cohorts with additional LT patients and healthy controls. Our study revealed a four-phase recovery process after LT and delineated changes in immune cell composition, expression programs, and interactions along this process. The intensity of the immune response differs between the ACR and non-ACR patients. Notably, the newly identified inflamed NK cells, CD14+RNASE2+ monocytes, and FOS-expressing monocytes emerged as predictive indicators of ACR. This study illuminates the longitudinal evolution of the immune cell landscape under tacrolimus-based immunosuppressive treatment during LT recovery, providing a four-phase framework that aids the clinical management of LT patients.

12.
Front Endocrinol (Lausanne) ; 14: 1216907, 2023.
Article in English | MEDLINE | ID: mdl-37732125

ABSTRACT

Diabetic Mellitus (DM), a chronic metabolic disorder disease characterized by hyperglycemia, is mainly caused by the absolute or relative deficiency of insulin secretion or decreased insulin sensitivity in target tissue cells. Dihydromyricetin (DMY) is a flavonoid compound of dihydroflavonol that widely exists in Ampelopsis grossedentata. This review aims to summarize the research progress of DMY in the treatment of DM. A detailed summary of related signaling induced by DMY are discussed. Increasing evidence implicates that DMY display hypoglycemic effects in DM via improving glucose and lipid metabolism, attenuating inflammatory responses, and reducing oxidative stress, with the signal transduction pathways underlying the regulation of AMPK or mTOR/autophagy, and relevant downstream cascades, including PGC-1α/SIRT3, MEK/ERK, and PI3K/Akt signal pathways. Hence, the mechanisms underlying the therapeutic implications of DMY in DM are still obscure. In this review, following with a brief introduction of the absorption, metabolism, distribution, and excretion characteristics of DMY, we summarized the current pharmacological developments of DMY as well as possible molecular mechanisms in the treatment of DM, aiming to push the understanding about the protective role of DMY as well as its preclinical assessment of novel application.


Subject(s)
Diabetes Mellitus , Hyperglycemia , Humans , Phosphatidylinositol 3-Kinases , Diabetes Mellitus/drug therapy , Flavonols/pharmacology , Flavonols/therapeutic use
14.
Bioresour Bioprocess ; 9(1): 103, 2022 Sep 24.
Article in English | MEDLINE | ID: mdl-38647572

ABSTRACT

Rapeseed meal (RSM) is an agro-industrial residue of increased functional biological value that contains high-quality proteins for animal feed. Due to the presence of antinutritional factors and immature development technology, RSM is currently used as a limited feed additive and in other relatively low-value applications. With increasing emphasis on green and sustainable industrial development and the added value of agro-industrial residues, considerable attention has been directed to the removal of antinutritional factors from RSM using high-efficiency, environment-friendly, and cost-effective biotechnology. Similarly, the high-value biotransformations of RSM have been the focus of research programmes to improve utilization rate. In this review, we introduce the sources, the nutrient and antinutrient content of RSM, and emphasize improvements on RSM feed quality using biological methods and its biotransformation applications.

15.
Commun Biol ; 5(1): 1151, 2022 10 30.
Article in English | MEDLINE | ID: mdl-36310238

ABSTRACT

Paraquat (PQ) is an efficient herbicide but leads to high mortality with no antidote in mammals. PQ produces reactive oxygen species (ROS), leading to epithelial-mesenchymal transition (EMT) for pulmonary fibrosis in type II alveolar (AT II) cells. Intriguingly, strategies reducing ROS exhibit limited therapeutic effects, indicating other targets existing for PQ toxicity. Herein we report that PQ is also an agonist for STIM1 that increases intracellular calcium levels. Particularly, PQ promotes STIM1 puncta formation and association with TRPC1 or ORAI for extracellular calcium entry and thus intracellular calcium influx. Further studies reveal the importance of P584&Y586 residues in STIM1 for PQ association that facilitates STIM1 binding to TRPC1. Consequently, the STIM1-TRPC1 route facilitates PQ-induced EMT for pulmonary fibrosis as well as cell death. Our results demonstrate that PQ is an agonist of STIM1 that induces extracellular calcium entry, increases intracellular calcium levels, and thus promotes EMT in AT II cells.


Subject(s)
Paraquat , Pulmonary Fibrosis , Animals , Paraquat/pharmacology , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/metabolism , Calcium , Reactive Oxygen Species , Epithelial-Mesenchymal Transition , Mammals
16.
J Clin Invest ; 132(2)2022 01 18.
Article in English | MEDLINE | ID: mdl-34847079

ABSTRACT

Therapeutics targeting osteoclasts are commonly used treatments for bone metastasis; however, whether and how osteoclasts regulate premetastatic niche and bone tropism are largely unknown. In this study, we report that osteoclast precursors (OPs) can function as a premetastatic niche component that facilitates breast cancer (BCa) bone metastasis at early stages. At the molecular level, unbiased GPCR ligand/agonist screening in BCa cells suggested that R-spondin 2 (RSPO2) and RANKL, through interaction with their receptor LGR4, promoted osteoclastic premetastatic niche formation and enhanced BCa bone metastasis. This was achieved by RSPO2/RANKL-LGR4 signal modulating the WNT inhibitor DKK1 through Gαq and ß-catenin signaling. DKK1 directly facilitated OP recruitment through suppression of its receptor LDL receptor-related protein 5 (LRP5) but not LRP6, upregulating Rnasek expression via inhibition of canonical WNT signaling. In clinical samples, RSPO2, LGR4, and DKK1 expression showed a positive correlation with BCa bone metastasis. Furthermore, soluble LGR4 extracellular domain (ECD) protein, acting as a decoy receptor for RSPO2 and RANKL, significantly alleviated bone metastasis and osteolytic lesions in a mouse bone metastasis model. These findings provide unique insights into the functional role of OPs as key components of the premetastatic niche for BCa bone metastasis and identify RSPO2/RANKL-LGR4 signaling as a promising target for inhibiting BCa bone metastasis.


Subject(s)
Bone Neoplasms/metabolism , Breast Neoplasms/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Neoplasm Proteins/metabolism , Osteoclasts/metabolism , RANK Ligand/metabolism , Receptors, G-Protein-Coupled/metabolism , Signal Transduction , Tumor Microenvironment , Animals , Bone Neoplasms/genetics , Breast Neoplasms/genetics , Breast Neoplasms/secondary , Cell Line, Tumor , Female , Humans , Intercellular Signaling Peptides and Proteins/genetics , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Metastasis , Neoplasm Proteins/genetics , RANK Ligand/genetics , Receptors, G-Protein-Coupled/genetics
17.
Toxicol Res (Camb) ; 10(4): 733-741, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34484664

ABSTRACT

Paraquat (PQ) and diquat (DQ), two highly efficient herbicides sharing similar chemical backbone, both induce reactive oxygen species and are highly toxic to humans and livestock, however, PQ but not DQ poisoning result in pulmonary fibrosis, the leading cause of high mortality rate in patients suffering PQ toxicity. Understanding the unique mechanism of PQ different from DQ therefore would provide potential strategies to reduce PQ-induced pulmonary fibrosis. Here, we identified that PQ but not DQ continuously upregulates TGF-ß expression in alveolar type II (AT II) cells. Importantly, such high expression of TGF-ß increases cytosolic calcium levels and further promotes the activation of calcineurin-NFAT axis. TGF-ß mainly activates NFATc1 and NFATc2, but not NFATc3 or NFATc4. Administration of the inhibitors targeting cytosolic calcium or calcineurin largely reverses PQ-induced epithelial-mesenchymal transition (EMT), whereas DQ has little effects on activation of NFAT and EMT. Ultimately, PQ poisoned patients exhibit significantly reduced blood calcium levels compared to DQ poisoning, possibly via the large usage of calcium by AT II cells. All in all, we found a vicious cycle that the upregulated TGF-ß in PQ-induced EMT further aggravates EMT via promotion of the calcium-calcineurin axis, which could be potential drug targets for treating PQ-induced pulmonary fibrosis.

18.
Front Oncol ; 11: 709835, 2021.
Article in English | MEDLINE | ID: mdl-34790565

ABSTRACT

BACKGROUND: The overall survival (OS) of patients diagnosed with colon cancer (CC) varied greatly, so did the patients with the same tumor stage. We aimed to design a nomogram that is capable of predicting OS in resected left-sided colon cancers (LSCC) and right-sided colon cancers (RSCC), and thus to stratify patients into different risk groups, respectively. METHODS: Records from a retrospective cohort of 577 patients with complete information were used to construct the nomogram. Univariate and multivariate analyses screened risk factors associated with overall survival. The performance of the nomogram was evaluated with concordance index (c-index), calibration plots, and decision curve analyses for discrimination, accuracy, calibration ability, and clinical net benefits, respectively, which was further compared with the American Joint Committee on Cancer (AJCC) 8th tumor-node-metastasis (TNM) classification. Risk stratification based on nomogram scores was performed with recursive partitioning analysis. RESULTS: The LSCC nomogram incorporated carbohydrate antigen 12-5 (CA12-5), age and log odds of positive lymph nodes (LODDS), and RSCC nomogram enrolled tumor stroma percentage (TSP), age and LODDS. Compared with the TNM classification, the LSCC and RSCC nomograms both had a statistically higher C-index (0.837, 95% CI: 0.827-0.846 and 0.780, 95% CI 0.773-0.787, respectively) and more clinical net benefits, respectively. Calibration plots revealed no deviations from reference lines. All results were reproducible in the validation cohort. CONCLUSIONS: An original predictive nomogram was constructed and validated for OS in patients with CC after surgery, which had facilitated physicians to appraise the individual survival of postoperative patients accurately and to identify high-risk patients who were in need of more aggressive treatment and follow-up strategies.

19.
Anim Biosci ; 34(3): 385-392, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33152222

ABSTRACT

OBJECTIVE: The present study was conducted to investigate the effects of lycopene on growth performance, abdominal fat deposition, serum lipids levels, activities of hepatic lipid metabolism related enzymes and genes expression in broiler chickens. METHODS: A total of 256 healthy one-day-old male Arbor Acres broiler chicks were randomly divided into four groups with eight replicates of eight birds each. Birds were fed basal diet supplemented with 0 (control), 100, 200, and 400 mg/kg lycopene, respectively. RESULTS: Dietary 100 mg/kg lycopene increased the body weight at 21 day of age compared to the control group (p<0.05). Compared to the basal diet, broilers fed diet with 100 mg/kg lycopene had decreased abdominal fat weight, and broilers fed diet with 100 and 200 mg/kg lycopene had decreased abdominal fat percentage (p<0.05). Compared to control, diets with 100, 200, and 400 mg/kg lycopene reduced the levels of total triglyceride and total cholesterol in serum, and diets with 100 and 200 mg/kg lycopene reduced the level of serum low density lipoprotein cholesterol (p<0.05). The activity of fatty acid synthase (FAS) in 400 mg/kg lycopene treated broilers and the activity of acetyl-CoA carboxylase (ACC) in 100, 200, and 400 mg/kg lycopene treated broilers were lower than those fed basal diet (p<0.05). Lycopene increased the mRNA abundance of adenosine monophosphate activated protein kinase α (AMPK-α), whereas decreased the mRNA abundance of sterol regulatory elementbinding protein 1, FAS, and ACC compared to the control group (p<0.05). CONCLUSION: Dietary lycopene supplementation can alleviate abdominal fat deposition and decrease serum lipids levels, possibly through activating the AMPK signaling pathway, thereby regulating lipid metabolism such as lipogenesis. Therefore, lycopene or lycopenerich plant materials might be added to poultry feed to regulate lipid metabolism.

20.
J Cell Physiol ; 225(1): 266-75, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20509140

ABSTRACT

Dauricine, a bioactive component of Asiatic Moonseed Rhizome, has been widely used to treat a large number of inflammatory diseases in traditional Chinese medicine. In our study, we demonstrated that dauricine inhibited colon cancer cell proliferation and invasion, and induced apoptosis by suppressing nuclear factor-kappaB (NF-kappaB) activation in a dose- and time-dependent manner. Addition of dauricine inhibited the phosphorylation and degradation of IkappaBalpha, and the phosphorylation and translocation of p65. Moreover, dauricine down-regulated the expression of various NF-kappaB-regulated genes, including genes involved cell proliferation (cyclinD1, COX2, and c-Myc), anti-apoptosis (survivin, Bcl-2, XIAP, and IAP1), invasion (MMP-9 and ICAM-1), and angiogenesis (VEGF). In athymic nu/nu mouse model, we further demonstrated that dauricine significantly suppressed colonic tumor growth. Taken together, our results demonstrated that dauricine inhibited colon cancer cell proliferation, invasion, and induced cell apoptosis by suppressing NF-kappaB activity and the expression profile of its downstream genes. These findings provide evidence for a novel role of dauricine in preventing or treating colon cancer through modulation of NF-kappaB singling pathway.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Apoptosis/drug effects , Benzylisoquinolines/pharmacology , Cell Proliferation/drug effects , Colonic Neoplasms/metabolism , NF-kappa B/metabolism , Signal Transduction/drug effects , Tetrahydroisoquinolines/pharmacology , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Benzylisoquinolines/chemistry , Benzylisoquinolines/therapeutic use , Caspases/metabolism , Cell Cycle/drug effects , Cell Line, Tumor , Colonic Neoplasms/drug therapy , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Humans , I-kappa B Proteins/metabolism , Mice , Mitogen-Activated Protein Kinase 8/metabolism , Mitogen-Activated Protein Kinase 9/metabolism , Molecular Structure , NF-KappaB Inhibitor alpha , Neoplasm Invasiveness , Neoplasm Transplantation , Poly(ADP-ribose) Polymerases/metabolism , Tetrahydroisoquinolines/chemistry , Tetrahydroisoquinolines/therapeutic use , p38 Mitogen-Activated Protein Kinases/metabolism
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