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1.
J Ethnopharmacol ; 332: 118364, 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-38763368

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Scutellaria baicalensis Georgi (SBG), a widely used traditional Chinese medicine, exhibits anti-inflammatory and antioxidant properties. Wogonin is one of the primary bioactive components of SBG. Acetaminophen (APAP)-induced liver injury (AILI) represents a prevalent form of drug-induced liver damage and is primarily driven by inflammatory responses and oxidative stress. AIM OF STUDY: To investigate the therapeutic effects of Wogonin on AILI and the underlying mechanisms. MATERIALS AND METHODS: C57BL/6 J mice were pre-treated with Wogonin (1, 2.5, and 5 mg/kg bodyweight) for 3 days, followed by treatment with APAP (300 mg/kg bodyweight). The serum and liver tissue samples were collected at 24 h post-APAP treatment. Bone marrow-derived macrophages and RAW264.7 cells were cultured and pre-treated with Wogonin (5, 10, and 20 µM) for 30 min, followed by stimulation with lipopolysaccharide (LPS; 100 ng/mL) for 3 h. To examine the role of the PI3K/AKT signaling pathway in the therapeutic effect of Wogonin on AILI, mice and cells were treated with LY294002 (a PI3K inhibitor) and MK2206 (an AKT inhibitor). RESULTS: Wogonin pre-treatment dose-dependently alleviated AILI in mice. Additionally, Wogonin suppressed oxidative stress and inflammatory responses. Liver transcriptome analysis indicated that Wogonin primarily regulates immune function and cytokines in AILI. Wogonin suppressed inflammatory responses of macrophages by inhibiting the PI3K/AKT signaling pathway. Consistently, Wogonin exerted therapeutic effects on AILI in mice through the PI3K/AKT signaling pathway. CONCLUSIONS: Wogonin alleviated AILI and APAP-induced hepatotoxicity in mice through the PI3K/AKT signaling pathway.


Subject(s)
Acetaminophen , Chemical and Drug Induced Liver Injury , Flavanones , Mice, Inbred C57BL , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Signal Transduction , Animals , Flavanones/pharmacology , Flavanones/therapeutic use , Acetaminophen/toxicity , Mice , Chemical and Drug Induced Liver Injury/drug therapy , Chemical and Drug Induced Liver Injury/prevention & control , Chemical and Drug Induced Liver Injury/metabolism , Chemical and Drug Induced Liver Injury/pathology , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Male , RAW 264.7 Cells , Phosphatidylinositol 3-Kinases/metabolism , Liver/drug effects , Liver/pathology , Liver/metabolism , Oxidative Stress/drug effects , Anti-Inflammatory Agents/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Scutellaria baicalensis/chemistry
2.
Cancer Lett ; 593: 216940, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38729554

ABSTRACT

Decreased levels of ß-hydroxybutyrate (BHB), a lipid metabolic intermediate known to slow the progression of colorectal cancer (CRC), have been observed in the colon mucosa of patients with inflammatory bowel diseases (IBD). In particular, patients with recurrent IBD present an increased risk of developing colitis-associated colorectal cancer (CAC). The role and molecular mechanism of BHB in the inflammatory and carcinogenic process of CAC remains unclear. Here, the anti-tumor effect of BHB was investigated in the Azoxymethane (AOM)/Dextran Sulfate Sodium (DSS)-induced CAC model and tumor organoids derivatives. The underlying mechanisms were studied using transcriptome and non-target metabolomic assay and further validated in colon tumor cell lineage CT26 in vitro. The tumor tissues and the nearby non-malignant tissues from colon cancer patients were collected to measure the expression levels of ketogenic enzymes. The exogenous BHB supplement lightened tumor burden and angiogenesis in the CAC model. Notably, transcriptome analysis revealed that BHB effectively decreased the expression of VEGFA in the CAC tumor mucosa. In vitro, BHB directly reduced VEGFA expression in hypoxic-treated CT26 cells by targeting transcriptional factor HIF-1α. Conversely, the deletion of HIF-1α largely reversed the inhibitory effect of BHB on CAC tumorigenesis. Additionally, decreased expression of ketogenesis-related enzymes in tumor tissues were associated with poor survival outcomes in patients with colon cancer. In summary, BHB carries out anti-angiogenic activity in CAC by regulating HIF-1α/VEGFA signaling. These findings emphasize the role of BHB in CAC and may provide novel perspectives for the prevention and treatment of colonic tumors.


Subject(s)
3-Hydroxybutyric Acid , Hypoxia-Inducible Factor 1, alpha Subunit , Neovascularization, Pathologic , 3-Hydroxybutyric Acid/pharmacology , 3-Hydroxybutyric Acid/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Animals , Mice , Humans , Colitis-Associated Neoplasms/pathology , Colitis-Associated Neoplasms/metabolism , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor A/genetics , Cell Line, Tumor , Carcinogenesis/drug effects , Male , Azoxymethane/toxicity , Colitis/complications , Colitis/metabolism , Colitis/pathology , Colitis/chemically induced , Dextran Sulfate , Disease Models, Animal , Angiogenesis
3.
Luminescence ; 39(5): e4778, 2024 May.
Article in English | MEDLINE | ID: mdl-38772865

ABSTRACT

To establish a new method for detecting crystal violet (CV), a harmful dye, herein, a genre of novel biomass carbon dots (CDs) was synthesized via a microwave method and employed as a fluorescent probe, in which water spinach and polyethylene glycol (PEG) performed as raw materials. Based on the inner filter effect (IFE) between the luminescent CDs and CV, the blue emission of this probe at 430 nm could be quenched by CV. Hence, a new strategy was proposed to selectively determine CV in aquaculture ambient. Moreover, under the optimal experiment conditions, this method showed a good linearity between the concentration of CV (c) and fluorescence quenching rate (ΔF/F0) in the concentration range of 4-200 µmol/L with the corresponding correlation coefficient (r) and the detection limit of 0.997 and 710 nmol/L, respectively. With advantages of environmental protectivity, sensitivity, affordability, and user-friendliness, the facilely fabricated CDs could be successfully applied in detecting CV in aquaculture samples, providing a technical foundation for monitoring the pollution of CV and ensuring the quality and safety of aquatic products.


Subject(s)
Biomass , Carbon , Fluorescent Dyes , Gentian Violet , Microwaves , Quantum Dots , Gentian Violet/chemistry , Carbon/chemistry , Quantum Dots/chemistry , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Spectrometry, Fluorescence , Fluorescence , Polyethylene Glycols/chemistry
4.
Sci Rep ; 13(1): 15045, 2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37700158

ABSTRACT

Virtual synchronous generator (VSG) not only increases the inertia of grid-connected system, but also brings the problem of active power oscillation under grid disturbance. Therefore, VSG control strategy and system model order reduction method with transient electromagnetic power compensation are proposed. The closed-loop active power small signal model of the system is established, and the influence of transient electromagnetic power compensation on the power stability of VSG is analyzed based on root locus method. By removing the items which have little influence on the stability of the system in the small signal model, the order is reduced to obtain the equivalent second-order model of the system. According to the second-order model, the quantitative design criteria of the system parameters are given. The proposed transient electromagnetic power compensation strategy not only increases the transient equivalent damping of the system, but also does not affect the primary frequency modulation characteristics and will not cause large overshoot of the output active power. The experimental results are consistent with the theoretical analysis, which testify the effectiveness and correctness of the system control strategy and the model reduction method.

5.
Chin Med ; 18(1): 97, 2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37542273

ABSTRACT

BACKGROUND: Myasthenia gravis (MG) is an antibody-mediated autoimmune disease and its pathogenesis is closely related to CD4 + T cells. In recent years, gut microbiota is considered to play an important role in the pathogenesis of MG. Astragaloside IV (AS-IV) is one of the main active components extracted from Astragalus membranaceus and has immunomodulatory effects. To study the immunomodulatory effect of AS-IV and the changes of gut microbiota on experimental autoimmune myasthenia gravis (EAMG) mice, we explore the possible mechanism of AS-IV in improving MG. METHODS: In this study, network pharmacology was utilized to screen the crucial targets of AS-IV in the treatment of MG. Subsequently, a Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was performed to identify potential pathways through which AS-IV acts against MG. Furthermore, experimental investigations were conducted to validate the underlying mechanism of AS-IV in MG treatment. Before modeling, 5 mice were randomly selected as the control group (CFA group), and the other 10 were induced to EAMG model. These mice were randomly divided into EAMG group and EAMG + AS-IV group, n = 5/group. In EAMG + AS-IV group, AS-IV was administered by gavage. CFA and EAMG groups were given the same volume of PBS. Body weight, grip strength and clinical symptoms were assessed and recorded weekly. At the last administration, the feces were collected for 16S RNA microbiota analysis. The levels of Treg, Th1 and Th17 cells in spleen and Th1 and Th17 cells in thymus were detected by flow cytometry. The levels of IFN-γ, IL-17 and TGF-ß in serum were measured by ELISA. Furthermore, fecal microbial transplantation (FMT) experiments were performed for exploring the influence of changed intestinal flora on EAMG. After EAMG model was induced, the mice were treated with antibiotics daily for 4 weeks to germ-free. Then germ-free EAMG mice were randomly divided into two groups: FMT EAMG group, FMT AS-IV group, n = 3/group. Fecal extractions from EAMG and EAMG + AS-IV groups as gathered above were used to administered daily to the respective groups for 4 weeks. Body weight, grip strength and clinical symptoms were assessed and recorded weekly. The levels of Treg, Th1 and Th17 cells in spleen and Th1 and Th17 cells in thymus were detected at the last administration. The levels of IFN-γ, IL-17 and TGF-ß in serum were measured by ELISA. RESULTS: The network pharmacology and KEGG pathway analysis revealed that AS-IV regulates T cell pathways, including T cell receptor signaling pathway and Th17 cell differentiation, suggesting its potential in improving MG. Further experimental verification demonstrated that AS-IV administration improved muscle strength and body weight, reduced the level of Th1 and Th17 cells, enhanced the level of Treg cells, and resulted in alterations of the gut microbiota, including changes in beta diversity, the Firmicutes/Bacteroidetes (F/B) ratio, and the abundance of Clostridia in EAMG mice. We further conducted FMT tests and demonstrated that the EAMG Abx-treated mice which were transplanted the feces of mice treated with AS-IV significantly alleviated myasthenia symptoms, reduced Th1 and Th17 cells levels, and increased Treg cell levels. CONCLUSION: This study speculated that AS-IV ameliorates EAMG by regulating CD4 + T cells and altering the structure and species of gut microbiota of EAMG.

6.
Microbiome ; 11(1): 96, 2023 05 02.
Article in English | MEDLINE | ID: mdl-37131223

ABSTRACT

BACKGROUND: The Western dietary pattern, characterized by high consumption of fats and sugars, has been strongly associated with an increased risk of developing Crohn's disease (CD). However, the potential impact of maternal obesity or prenatal exposure to a Western diet on offspring's susceptibility to CD remains unclear. Herein, we investigated the effects and underlying mechanisms of a maternal high-fat/high-sugar Western-style diet (WD) on offspring's susceptibility to 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced Crohn's-like colitis. METHODS: Maternal dams were fed either a WD or a normal control diet (ND) for eight weeks prior to mating and continued throughout gestation and lactation. Post-weaning, the offspring were subjected to WD and ND to create four groups: ND-born offspring fed a normal diet (N-N) or Western diet (N-W), and WD-born offspring fed a normal (W-N) or Western diet (W-W). At eight weeks of age, they were administered TNBS to induce a CD model. RESULTS: Our findings revealed that the W-N group exhibited more severe intestinal inflammation than the N-N group, as demonstrated by a lower survival rate, increased weight loss, and a shorter colon length. The W-N group displayed a significant increase in Bacteroidetes, which was accompanied by an accumulation of deoxycholic acid (DCA). Further experimentation confirmed an increased generation of DCA in mice colonized with gut microbes from the W-N group. Moreover, DCA administration aggravated TNBS-induced colitis by promoting Gasdermin D (GSDMD)-mediated pyroptosis and IL-1beta (IL-1ß) production in macrophages. Importantly, the deletion of GSDMD effectively restrains the effect of DCA on TNBS-induced colitis. CONCLUSIONS: Our study demonstrates that a maternal Western-style diet can alter gut microbiota composition and bile acid metabolism in mouse offspring, leading to an increased susceptibility to CD-like colitis. These findings highlight the importance of understanding the long-term consequences of maternal diet on offspring health and may have implications for the prevention and management of Crohn's disease. Video Abstract.


Subject(s)
Colitis , Crohn Disease , Prenatal Exposure Delayed Effects , Humans , Pregnancy , Female , Mice , Animals , Crohn Disease/chemically induced , Diet, Western/adverse effects , Colitis/chemically induced , Diet, High-Fat/adverse effects , Deoxycholic Acid , Mice, Inbred C57BL
7.
Comput Struct Biotechnol J ; 21: 1606-1620, 2023.
Article in English | MEDLINE | ID: mdl-36874158

ABSTRACT

Short-chain fatty acids (SCFAs) exhibit anticancer activity in cellular and animal models of colon cancer. Acetate, propionate, and butyrate are the three major SCFAs produced from dietary fiber by gut microbiota fermentation and have beneficial effects on human health. Most previous studies on the antitumor mechanisms of SCFAs have focused on specific metabolites or genes involved in antitumor pathways, such as reactive oxygen species (ROS) biosynthesis. In this study, we performed a systematic and unbiased analysis of the effects of acetate, propionate, and butyrate on ROS levels and metabolic and transcriptomic signatures at physiological concentrations in human colorectal adenocarcinoma cells. We observed significantly elevated levels of ROS in the treated cells. Furthermore, significantly regulated signatures were involved in overlapping pathways at metabolic and transcriptomic levels, including ROS response and metabolism, fatty acid transport and metabolism, glucose response and metabolism, mitochondrial transport and respiratory chain complex, one-carbon metabolism, amino acid transport and metabolism, and glutaminolysis, which are directly or indirectly linked to ROS production. Additionally, metabolic and transcriptomic regulation occurred in a SCFAs types-dependent manner, with an increasing degree from acetate to propionate and then to butyrate. This study provides a comprehensive analysis of how SCFAs induce ROS production and modulate metabolic and transcriptomic levels in colon cancer cells, which is vital for understanding the mechanisms of the effects of SCFAs on antitumor activity in colon cancer.

8.
Macromol Rapid Commun ; 44(1): e2200246, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35526256

ABSTRACT

Lithium-sulfur (Li-S) batteries with high sulfur utilization, long-cycle life, and dendrite-free features hold great promise for the development of next-generation energy storage devices of high energy density. Considerable efforts have been committed to solving the polysulfide shuttle problem toward highly stable Li-S batteries. Here, a unique polymer network containing dually anchored ionic liquids (DA-PIL) is devolped to improve the cycling performance and coulombic efficiency of Li-S batteries. This DA-PIL electrolyte incorporates the amphiphilicity of both the polysulfides anion and lithium cation, creating an ionic function layer on polypropylene separator. Noteworthily, the DA-PIL network is "clean" in the sense that no free ionic specifies are introduced to the electrolyte system. The DA-PIL layer not only enables strong supression against polysulfide shuttling but simultaneously allows fast lithium transportation owing to cooperate electrostatic interaction among anchored cations and anions. The DA-PIL layer functionalized on a polypropylene separator can boost excellent stability of Li-S battery with >1600 h cycling test at 0.25 mA cm-2 . The Li-S cell with DA-PIL layer delivers a higher discharge capacity of 827.4 mAh g-1 at 1C. A discharge capacity of 630.6 mAh g-1 is retained after 1000 cycles.


Subject(s)
Ionic Liquids , Lithium , Polypropylenes , Polymers , Sulfur
9.
Toxicology ; 482: 153367, 2022 12.
Article in English | MEDLINE | ID: mdl-36330926

ABSTRACT

Cyadox, a potential antimicrobial growth promoter, has been widely studied and prospected to be used as an additive in livestock and poultry feed. Although high cyadox exposure has been reported to cause toxicity, the exact metabolic effects are not fully understood. Our study aim is to evaluate the metabolic effects of cyadox using comprehensive methods including serum clinical chemical test, histopathology analysis, metabolomics, and transcriptomics profile analysis. One single acute dosage over 7-day course and one subchronic 90-day dietary ingestion of cyadox intervention were conducted on the Wistar rats separately. Dose-dependent alterations were shown in the metabolism of the urine, kidney, plasma, and liver by metabolomics analysis. We further investigated gene expressions of the liver administered with high dose of cyadox for 12 weeks. Top sixty-six differentially expressed genes involved in the pathways, including xenobiotic (cyadox) metabolism, lipid metabolism, energy metabolism, nucleic acid metabolic process, inflammatory response, and response to the oxidative stress, which were in concordance with these metabolic alternations. Our study provided a comprehensive information on how cyadox modulates the metabolism and gene expressions, which is vital when considering the safe application of cyadox.


Subject(s)
Quinoxalines , Transcriptome , Rats , Animals , Rats, Wistar , Metabolomics
10.
Int J Comput Assist Radiol Surg ; 17(10): 1891-1902, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35851828

ABSTRACT

PURPOSE: In computer-assisted diagnosis for orthopedic treatment, 3D reconstruction of bones is critical. Traditional 3D imaging technologies like CT and MRI have been proposed, but their high radiation dose and the requirements for lying postures could impact the accuracy of reconstructed bones and diagnosis results. Meanwhile, methods based on bone contours always depend on prior knowledge and lack precise bone segmentation methods. To address these issues, a bone reconstruction method based on multi-views of contours is proposed, as well as a hybrid CNN-Transformer approach for bone contours segmentation. METHODS: A four-step strategy is introduced including segmenting bone contours from X-ray images, calculating 3D sparse, dense point clouds based on contours, and reconstructing surface. The Trans-DetSeg approach for interest regions detection and bone segmentation is proposed for accurate contours. Besides, the mathematical description of mapping relationships between contours in different views of X-ray images is provided. Then, bone sparse and dense point clouds are generated subsequently. Based on dense point clouds and the power crust method, realistic bone models are reconstructed. RESULTS: Evaluated on 301 bone X-ray images and by considering p-value < 0.05, the proposed Trans-Detseg approach performed better with Dice Similarity Coefficient of 0.949 and Hausdorff Distance of 26.17 than three state-of-the-art models. Furthermore, the accuracy of the bone 3D reconstruction was investigated in three tibia cases and the proposed method was verified based on comparisons of results and CT data. It was proved that increased views of X-ray images could reduce the Average Surface Distance and perfect the structure information of reconstructed bones. CONCLUSION: A new method for bone 3D reconstruction based on segmented bone contours on multi-views of X-ray images has been developed. Besides, a hybrid CNN-Transformer approach is introduced to segment bone contours. Evaluations proved the efficiency and accuracy of the proposed bone 3D reconstruction method.


Subject(s)
Imaging, Three-Dimensional , Tomography, X-Ray Computed , Bone and Bones/diagnostic imaging , Humans , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging , Radiography , Tomography, X-Ray Computed/methods
11.
Int J Mol Sci ; 23(11)2022 Jun 02.
Article in English | MEDLINE | ID: mdl-35682941

ABSTRACT

Lactate, primarily produced by the gut microbiota, performs as a necessary "information transmission carrier" between the gut and the microbiota. To investigate the role of lactate in the gut epithelium cell-microbiota interactions as a metabolic signal, we performed a combinatory, global, and unbiased analysis of metabolomic and transcriptional profiling in human colon epithelial cells (Caco-2), using a lactate treatment at the physiological concentration (8 mM). The data demonstrated that most of the genes in oxidative phosphorylation were significantly downregulated in the Caco-2 cells due to lactate treatment. Consistently, the levels of fumarate, adenosine triphosphate (ATP), and creatine significantly decreased, and these are the metabolic markers of OXPHOS inhibition by mitochondria dysfunction. The one-carbon metabolism was affected and the polyol pathway was activated at the levels of gene expression and metabolic alternation. In addition, lactate significantly upregulated the expressions of genes related to self-protection against apoptosis. In conclusion, lactate participates in gut-gut microbiota communications by remodeling the metabolomic and transcriptional signatures, especially for the regulation of mitochondrial function. This work contributes comprehensive information to disclose the molecular mechanisms of lactate-mediated functions in human colon epithelial cells that can help us understand how the microbiota communicates with the intestines through the signaling molecule, lactate.


Subject(s)
Lactic Acid , Transcriptome , Caco-2 Cells , Colon , Epithelial Cells/metabolism , Humans , Lactic Acid/metabolism
12.
BMC Med ; 20(1): 148, 2022 04 15.
Article in English | MEDLINE | ID: mdl-35422042

ABSTRACT

BACKGROUND: Ketone body ß-hydroxybutyrate (BHB) has received more and more attentions, because it possesses a lot of beneficial, life-preserving effects in the fields of clinical science and medicine. However, the role of BHB in intestinal inflammation has not yet been investigated. METHODS: Colonic mucosa of inflammatory bowel disease (IBD) patients and healthy controls were collected for evaluation of BHB level. Besides, the therapeutic effect of exogenous BHB in a murine model of acute dextran sulfate sodium (DSS)-induced colitis were assessed by body weight change, colon length, disease activity index, and histopathological sections. The regulatory effectors of BHB were analyzed by RT-qPCR, immunofluorescence, and microbe analysis in vivo. Moreover, the molecular mechanism of BHB was further verified in bone marrow-derived macrophages (BMDMs). RESULTS: In this study, significantly reduced BHB levels were found in the colonic mucosa from IBD patients and correlated with IBD activity index. In addition, we demonstrated that the administration of exogenous BHB alleviated the severity of acute experimental colitis, which was characterized by less weight loss, disease activity index, colon shortening, and histology scores, as well as decreased crypt loss and epithelium damage. Furthermore, BHB resulted in significantly increased colonic expression of M2 macrophage-associated genes, including IL-4Ra, IL-10, arginase 1 (Arg-1), and chitinase-like protein 3, following DSS exposure, suggesting an increased M2 macrophage skewing in vivo. Moreover, an in vitro experiment revealed that the addition of BHB directly promoted STAT6 phosphorylation and M2 macrophage-specific gene expression in IL-4-stimulated macrophages. Besides, we found that BHB obviously increased M2 macrophage-induced mucosal repair through promoting intestinal epithelial proliferation. However, the enhancement effect of BHB on M2 macrophage-induced mucosal repair and anti-inflammation was completely inhibited by the STAT6 inhibitor AS1517499. CONCLUSIONS: In summary, we show that BHB promotes M2 macrophage polarization through the STAT6-dependent signaling pathway, which contributes to the resolution of intestinal inflammation and the repair of damaged intestinal tissues. Our finding suggests that exogenous BHB supplement may be a useful therapeutic approach for IBD treatment.


Subject(s)
Colitis , Inflammatory Bowel Diseases , 3-Hydroxybutyric Acid/metabolism , 3-Hydroxybutyric Acid/pharmacology , 3-Hydroxybutyric Acid/therapeutic use , Animals , Colitis/chemically induced , Colitis/drug therapy , Colitis/metabolism , Dextran Sulfate/adverse effects , Dextran Sulfate/metabolism , Disease Models, Animal , Humans , Inflammation/metabolism , Inflammatory Bowel Diseases/drug therapy , Macrophages , Mice , Mice, Inbred C57BL , STAT6 Transcription Factor/metabolism , STAT6 Transcription Factor/pharmacology , Signal Transduction
13.
Cancer Lett ; 529: 1-10, 2022 03 31.
Article in English | MEDLINE | ID: mdl-34979164

ABSTRACT

Although radiotherapy is an important clinical option available for colorectal cancer (CRC), its use is restricted due to low radiosensitivity of CRC and high toxicity to surrounding normal tissues. The purpose of this study is to investigate the molecular mechanism by which CRC is not sensitive to radiation and radiation causes toxicity to surrounding normal tissues. Here we found that GSDME was silenced in CRC but markedly expressed in their surrounding normal tissues. GSDME determines radiation-induced pyroptosis in CRC cells and normal epithelial cells through the caspase-3-dependent pathway. GSDME expression sensitizes radioresistant CRC cells to radiation. In the homograft model, after radiation treatment, the tumor volume and weight were significantly decreased in GSDME-expressed homograft tumors compared to GSDME-knockout homograft tumors. On the mechanism, radiation induced GSDME-mediated pyroptosis in CRC cells, which recruited and activated NK cells to enhance antitumor immunity. In addition, GSDME-knockout mice were protected from radiation-induced weight loss and tissue damages in the intestine, stomach, liver and pancreas compared to wild-type control littermates. In summary, we show that GSDME determines CRC radiosensitivity and radiation-related toxicity to surrounding normal tissues through caspase-3-dependent pyroptosis. Our finding reveals a previously unrecognized link between radiation and pyroptosis.


Subject(s)
Colorectal Neoplasms/complications , Colorectal Neoplasms/genetics , Gastrointestinal Diseases/etiology , Pore Forming Cytotoxic Proteins/genetics , Radiation Injuries/etiology , Radiation Tolerance , Animals , Biomarkers, Tumor , Caspase 3/metabolism , Cell Line, Tumor , Colitis/etiology , Colitis/metabolism , Colitis/pathology , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/radiotherapy , Cytokines/metabolism , Disease Models, Animal , Gastrointestinal Diseases/diagnosis , Gastrointestinal Diseases/metabolism , Gene Expression , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Killer Cells, Natural/pathology , Lymphocyte Depletion , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Lymphocytes, Tumor-Infiltrating/pathology , Mice , Mice, Knockout , Pore Forming Cytotoxic Proteins/metabolism , Prognosis , Pyroptosis/genetics , Pyroptosis/radiation effects , Radiation Injuries/diagnosis , Radiation Injuries/metabolism , Radiotherapy/adverse effects , Radiotherapy/methods
14.
J Crohns Colitis ; 16(1): 133-142, 2022 Jan 28.
Article in English | MEDLINE | ID: mdl-34309645

ABSTRACT

BACKGROUND: Shedding of intestinal epithelial cells [IECs] is a potent cause of barrier loss which plays an important role in the pathogenesis of inflammatory bowel disease [IBD]. TNFα can induce IEC shedding, but little is known about this process. METHODS: To investigate the molecular mechanism regulating IEC shedding, mice lacking interferon regulatory factor1 [IRF1], caspase-3, or gasdermin E [GSDME] and their control wild-type [WT] littermates were intravenously injected with tumour necrosis factor alpha [TNFα] to establish an IEC shedding model. A dual-luciferase reporter assay and a chromatin immunoprecipitation assay were used to determine the role of IRF1 in regulating caspase-3 expression. RESULTS: TNFα administration induced obvious IEC shedding in WT mice, but IRF1-/- and caspase-3-/-mice were completely protected from TNFα-induced IEC shedding. As a critical transcription factor, IRF1 was found to be required for caspase-3 expression in IECs by binding to IRF1-binding sites in the caspase-3 promoter. In WT mice, plasma membrane integrity was disrupted in shed IECs; these cells were swollen and contained GSDME-N terminal [NT] fragments which are responsible for the induction of pyroptosis. However, in GSDME-/- mice, plasma membrane integrity was not disrupted in shed IECs, which were not swollen and did not contain GSDME-NT, indicating that GSDME converted TNFα-induced IEC shedding into a pyroptotic cell death process. In addition, IRF1 deficiency resulted in decreases in mucosal inflammation and mucosal bacteria levels in TNFα-challenged colons. CONCLUSIONS: IRF1 deficiency maintains intestinal barrier integrity by restricting TNFα-induced IEC shedding.


Subject(s)
Epithelial Cells/pathology , Interferon Regulatory Factor-1/metabolism , Intestinal Mucosa/cytology , Tumor Necrosis Factor-alpha/pharmacology , Animals , Caspase 3/metabolism , Cell Death , Cells, Cultured , Humans , Mice , Transfection
15.
Cell Rep ; 35(11): 109265, 2021 06 15.
Article in English | MEDLINE | ID: mdl-34133932

ABSTRACT

Crohn's disease (CD) is a kind of refractory intestinal inflammatory diseases. Pyroptosis was recently identified as a gasdermin-mediated proinflammatory cell death. However, it is unclear whether gasdermin-mediated pyroptosis participates in the pathogenesis of CD. Here, we show that the pyroptosis-inducing fragment GSDME N-terminal is obviously detected in the inflamed colonic mucosa but not in the uninflamed mucosa of patients with CD, suggesting that GSDME-mediated pyroptosis may be correlated with intestinal mucosal inflammation in CD. To investigate the role of GSDME in colitis development, Gsdme-/- mice and wild-type (WT) littermate controls were treated with 2,4,6-trinitrobenzenesulfonic acid (TNBS) to induce colitis. We found that Gsdme-/- mice exhibit less-severe intestinal inflammation than WT controls do. Furthermore, our results indicate that GSDME-mediated epithelial-cell pyroptosis induces intestinal inflammation through the release of proinflammatory intracellular contents. In summary, we show that GSDME participates in the pathogenesis of CD through GSDME-mediated pyroptosis to release proinflammatory cytokines.


Subject(s)
Crohn Disease/pathology , Inflammation/pathology , Intestines/pathology , Pore Forming Cytotoxic Proteins/metabolism , Pyroptosis , Animals , Colitis/chemically induced , Colitis/immunology , Colitis/metabolism , Colitis/pathology , Epithelial Cells/metabolism , Epithelial Cells/pathology , HMGB1 Protein/metabolism , Hematopoiesis , Humans , Intestinal Mucosa/pathology , Male , Mice, Inbred C57BL , Pore Forming Cytotoxic Proteins/deficiency , Severity of Illness Index , Trinitrobenzenesulfonic Acid
16.
J Hematol Oncol ; 13(1): 149, 2020 11 07.
Article in English | MEDLINE | ID: mdl-33160389

ABSTRACT

BACKGROUND: Pyroptosis is a form of proinflammatory gasdermin-mediated programmed cell death. Abnormal mucosal inflammation in the intestine is a critical risk factor for colitis-associated colorectal cancer (CAC). However, it is unknown whether pyroptosis participates in the development of CAC. METHODS: To investigate the role of gasdermin E (GSDME)-mediated pyroptosis in the development of CAC, Gsdme-/- mice and their wild-type (WT) littermate controls were challenged with azoxymethane (AOM) and dextran sodium sulfate (DSS) to induce a CAC model. Neutralizing antibodies against high-mobility group box protein 1 (HMGB1) were used to determine the role of HMGB1 in CAC. To identify the role of ERK1/2 in HMGB1-induced colon cancer cell proliferation, we performed western blotting and CCK8 assays using the ERK1/2-specific inhibitor U0126 in CT26 colon cancer cells. RESULTS: In the CAC model, Gsdme-/- mice exhibited reduced weight loss and colon shortening, attenuated rectal prolapse, and reduced tumor numbers and sizes compared to WT littermates. Furthermore, treatment with neutralizing anti-HMGB1 antibodies decreased the numbers and sizes of tumors, ERK1/2 activation and proliferating cell nuclear antigen (PCNA) expression in AOM/DSS-challenged WT mice. In addition, our in vitro experiments demonstrated that HMGB1 induced proliferation and PCNA expression in CT26 colon cancer cells through the ERK1/2 pathway. CONCLUSION: GSDME-mediated pyroptosis promotes the development of CAC by releasing HMGB1, which induces tumor cell proliferation and PCNA expression through the ERK1/2 pathway. This finding reveals a previously unrecognized link between pyroptosis and CAC tumorigenesis and offers new insight into CAC pathogenesis.


Subject(s)
Carcinogenesis/pathology , Colitis-Associated Neoplasms/pathology , HMGB1 Protein/metabolism , Intestinal Mucosa/pathology , MAP Kinase Signaling System , Receptors, Estrogen/metabolism , Animals , Carcinogenesis/metabolism , Colitis-Associated Neoplasms/metabolism , Humans , Intestinal Mucosa/metabolism , Mice , Mice, Inbred C57BL , Pyroptosis
17.
J Crohns Colitis ; 13(4): 482-494, 2019 Mar 30.
Article in English | MEDLINE | ID: mdl-30445446

ABSTRACT

BACKGROUND AND AIMS: Macrophages are a promising therapeutic target for intestinal mucosal repair. MiR-146b appears to control macrophage activation and cell proliferation. METHODS: By loading miR-146b mimic on mannose-modified trimethyl chitosan [MTC]-conjugated nanoparticles [NPs] [MTC-miR146b], a molecular targeted immunotherapeutic approach was developed to selectively target intestinal macrophages for mucosal regeneration and tumourigenesis in mouse models. RESULTS: We first confirmed that miR-146b expression was significantly enhanced during mucosal regeneration in a murine colitis model. Moreover, after mucosal damage, MTC-miR146b mimic-treated wild-type mice had dramatically restored body weight and mucosal barrier function compared with MTC-NC treated mice. Strikingly, MTC-miR146b mimic oral administration protected miR-146b-deficient mice from dextran sodium sulphate [DSS] injury and the colitis-associated cancer process. Mechanistically, miR-146b strongly inhibited M1 macrophage activation by suppressing the Toll-like receptor 4 [TLR4] signalling pathway, resulting in the repression of the induction of pro-inflammatory cytokines including TNF-α, IL-6, and IL-1ß. More importantly, miR-146b overexpression in bone marrow-derived macrophages [BMDMs] in M1 differentiation conditions induced a phenotype similar to M2 macrophages and improved the proliferation of co-cultured colonic epithelial cells via STAT3-dependent IL-10 production. CONCLUSIONS: MTC-miR146b should be regarded as an effective candidate for oral delivery and could improve the efficacy of immunotherapies for ulcerative colitis and colitis-associated cancer.


Subject(s)
Colitis/drug therapy , Immunotherapy/methods , Intestinal Mucosa/physiopathology , Macrophages/physiology , MicroRNAs/therapeutic use , Molecular Targeted Therapy/methods , Administration, Oral , Animals , Body Weight/drug effects , Carcinogenesis/drug effects , Cell Proliferation/drug effects , Colitis/chemically induced , Colitis/pathology , Colitis/prevention & control , Colitis, Ulcerative/drug therapy , Dextran Sulfate , Disease Models, Animal , Interleukin-10/metabolism , Intestinal Mucosa/immunology , Macrophage Activation/drug effects , Male , Mice , MicroRNAs/administration & dosage , MicroRNAs/genetics , Nanoparticles/therapeutic use , Phenotype , Regeneration/drug effects , STAT3 Transcription Factor/metabolism , Signal Transduction/drug effects , Toll-Like Receptor 4/antagonists & inhibitors
18.
Plant J ; 93(1): 92-106, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29086444

ABSTRACT

Sesquiterpene lactones (STLs) are C15 terpenoid natural products with α-methylene γ-lactone moiety. A large proportion of STLs in Asteraceae species is derived from the central precursor germacrene A acid (GAA). Formation of the lactone rings depends on the regio-(C6 or C8) and stereoselective (α- or ß-)hydroxylations of GAA, producing STLs with four distinct stereo-configurations (12,6α-, 12,6ß-, 12,8α-, and 12,8ß-olide derivatives of GAA) in nature. Curiously, two configurations of STLs (C12,8α and C12,8ß) are simultaneously present in the Chinese medicinal plant, Inula hupehensis. However, how these related yet distinct STL stereo-isomers are co-synthesized in I. hupehensis remains unknown. Here, we describe the functional identification of the I. hupehensis cytochrome P450 (CYP71BL6) that can catalyze the hydroxylation of GAA in either 8α- or 8ß-configuration, resulting in the synthesis of both 8α- and 8ß-hydroxyl GAAs. Of these two products, only 8α-hydroxyl GAA spontaneously lactonizes to the C12,8α-STL while the 8ß-hydroxyl GAA remains stable without lactonization. Chemical structures of the C12,8α-STL, named inunolide, and 8ß-hydroxyl GAA were fully elucidated by nuclear magnetic resonance analysis and mass spectrometry. The CYP71BL6 displays 63-66% amino acid identity to the previously reported CYP71BL1/2 catalyzing GAA 6α- or 8ß-hydroxylation, indicating CYP71BL6 shares the same evolutionary lineage with other stereoselective cytochrome P450s, but catalyzes hydroxylation in a non-stereoselective manner. We observed that the CYP71BL6 transcript abundance correlates closely to the accumulation of C12,8-STLs in I. hupehensis. The identification of CYP71BL6 provides an insight into the biosynthesis of STLs in Asteraceae.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Inula/enzymology , Sesquiterpenes, Germacrane/metabolism , Sesquiterpenes/metabolism , Catalysis , Cytochrome P-450 Enzyme System/genetics , Hydroxylation , Inula/genetics , Inula/metabolism , Lactones/chemistry , Lactones/metabolism , Oxidation-Reduction , Plant Proteins/genetics , Plant Proteins/metabolism , Plants, Medicinal , Sesquiterpenes/chemistry , Sesquiterpenes, Germacrane/chemistry
19.
J Magn Reson ; 268: 1-9, 2016 07.
Article in English | MEDLINE | ID: mdl-27131476

ABSTRACT

Mapping B0-field and shim functions spatially is a crucial step in the gradient shimming. The conventional estimation method used in the phase difference imaging technique takes no account for noise and T2(∗) effects, and is prone to create noisy and distorted field maps. This paper describes a new gradient shimming based on the regularized estimation for B0-field and shim functions. Based on a statistical model, the B0-field and shim function maps are estimated by a Penalized Maximum Likelihood method that minimizes two regularized least-squares cost functions, respectively. The first cost function of B0-field exploits the two facts that the noise in the phase difference measurements is Gaussian and the B0-field maps tend to be smooth. And the other one adds an additional fact that each shim function corresponds to a given spherical harmonic of the magnetic field. Significant improvements in the quality of field mapping and in the final shimming results are demonstrated through computer simulations as well as experiments, especially when the magnetic field homogeneity is poor.

20.
J Agric Food Chem ; 64(2): 470-7, 2016 Jan 20.
Article in English | MEDLINE | ID: mdl-26702945

ABSTRACT

Different ginger cultivars may contain different nutritional and medicinal values. In this study, a time-domain nuclear magnetic resonance method was employed to study water dynamics in different ginger cultivars. Significant differences in transverse relaxation time T2 values assigned to the distribution of water in different parts of the plant were observed between Henan ginger and four other ginger cultivars. Ion concentration and metabolic analysis showed similar differences in Mn ion concentrations and organic solutes among the different ginger cultivars, respectively. On the basis of Pearson's correlation analysis, many organic solutes and 6-gingerol, the main active substance of ginger, exhibited significant correlations with water distribution as determined by NMR T2 relaxation, suggesting that the organic solute differences may impact water distribution. Our work demonstrates that low-field NMR relaxometry provides useful information about water dynamics in different ginger cultivars as affected by the presence of different organic solutes.


Subject(s)
Magnetic Resonance Imaging/methods , Water/chemistry , Zingiber officinale/chemistry , Biological Transport , Catechols/chemistry , Catechols/metabolism , Fatty Alcohols/chemistry , Fatty Alcohols/metabolism , Zingiber officinale/classification , Zingiber officinale/metabolism , Water/metabolism
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