Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 36
Filter
1.
EMBO J ; 38(1)2019 01 03.
Article in English | MEDLINE | ID: mdl-30396996

ABSTRACT

Targeting immune checkpoints, such as PD-L1 and its receptor PD-1, has opened a new avenue for treating cancers. Understanding the regulatory mechanism of PD-L1 and PD-1 will improve the clinical response rate and efficacy of PD-1/PD-L1 blockade in cancer patients and the development of combinatorial strategies. VGLL4 inhibits YAP-induced cell proliferation and tumorigenesis through competition with YAP for binding to TEADs. However, whether VGLL4 has a role in anti-tumor immunity is largely unknown. Here, we found that disruption of Vgll4 results in potent T cell-mediated tumor regression in murine syngeneic models. VGLL4 deficiency reduces PD-L1 expression in tumor cells. VGLL4 interacts with IRF2BP2 and promotes its protein stability through inhibiting proteasome-mediated protein degradation. Loss of IRF2BP2 results in persistent binding of IRF2, a transcriptional repressor, to PD-L1 promoter. In addition, YAP inhibits IFNγ-inducible PD-L1 expression partially through suppressing the expression of VGLL4 and IRF1 by YAP target gene miR-130a. Our study identifies VGLL4 as an important regulator of PD-L1 expression and highlights a central role of VGLL4 and YAP in the regulation of tumor immunity.


Subject(s)
B7-H1 Antigen/genetics , Transcription Factors/genetics , Tumor Escape/genetics , A549 Cells , Adaptor Proteins, Signal Transducing/physiology , Animals , Cells, Cultured , Gene Deletion , Gene Expression Regulation, Neoplastic , HEK293 Cells , HeLa Cells , Humans , Mice , Mice, Inbred C57BL , Mice, Nude , Oncogenes/genetics , RNA Interference , Transcription Factors/physiology , YAP-Signaling Proteins
2.
Opt Express ; 30(13): 23463-23474, 2022 Jun 20.
Article in English | MEDLINE | ID: mdl-36225025

ABSTRACT

The modulation of structural color through various methods has attracted considerable attention. Herein, a new modulation method for the structural colors in all-dielectric photonic crystals (PCs) using energetic ion beams is proposed. One type of periodic PC and two different defective PCs were experimentally investigated. Under carbon-ion irradiation, the color variation primarily originated from the blue shift of the optical spectra. The varying degrees of both the reflection and transmission structural colors mainly depended on the carbon-ion fluences. Such nanostructures are promising for tunable color filters and double-sided chromatic displays based on PCs.

3.
Opt Express ; 29(20): 31915-31923, 2021 Sep 27.
Article in English | MEDLINE | ID: mdl-34615273

ABSTRACT

We theoretically and experimentally investigate the angle-dependent omnidirectional photonic bandgap (PBG) in one-dimensional photonic crystals (PCs) comprising hyperbolic metamaterials (HMMs) for TM polarization, which is different from blue-shifted PBG in conventional all-dielectric photonic crystals. The frequency range of PBG increases when the incident angles increase, owing to the red-shift and blue-shift of the long-wavelength and short-wavelength band edges, respectively. The red-shifted band edge originates from the phase-variation compensation mechanism between the HMMs and dielectric material. The experimental values are in good agreement with the simulation results. These nanostructures are ideal for fabricating photonic devices such as omnidirectional reflectors.

4.
Acta Biochim Biophys Sin (Shanghai) ; 52(7): 716-722, 2020 Jul 10.
Article in English | MEDLINE | ID: mdl-32445469

ABSTRACT

The renewal of lung epithelial cells is normally slow unless the lung is injured. The resident epithelial stem cells rapidly proliferate and differentiate to maintain lung structure and function when the lung is damaged. The alveolar epithelium is characterized by alveolar type 1 (AT1) and alveolar type 2 (AT2) cells. AT2 cells are the stem cells for alveoli, as they can both self-renew and generate AT1 cells. Abnormal proliferation and regulation of AT2 cells will lead to serious lung diseases including cancers. In this review, we focused on the alveolar stem/progenitor cells, the key physiological function of AT2 cells in lung homeostasis and the complicated regulation of AT2 cells in the repairing processes after lung injury.


Subject(s)
Alveolar Epithelial Cells/physiology , Cell Differentiation , Lung Injury/metabolism , Lung Neoplasms/metabolism , Regeneration , Stem Cells/metabolism , Alveolar Epithelial Cells/pathology , Animals , Humans , Lung Injury/pathology , Lung Neoplasms/pathology , Stem Cells/pathology
5.
J Biol Chem ; 293(14): 5160-5171, 2018 04 06.
Article in English | MEDLINE | ID: mdl-29475944

ABSTRACT

The liver is a major organ in lipid metabolism, and its malfunction leads to various diseases. Nonalcoholic fatty liver disease, the most common chronic liver disorder in developed countries, is characterized by the abnormal retention of excess lipid within hepatocytes and predisposes individuals to liver cancer. We previously reported that the levels of Lissencephaly 1 (LIS1, also known as PAFAH1B1) are down-regulated in human hepatocellular carcinoma. Following up on this observation, we found that genetic deletion of Lis1 in the mouse liver increases lipid accumulation and inflammation in this organ. Further analysis revealed that loss of Lis1 triggers endoplasmic reticulum (ER) stress and reduces triglyceride secretion. Attenuation of ER stress by addition of tauroursodeoxycholic acid (TUDCA) diminished lipid accumulation in the Lis1-deficient hepatocytes. Moreover, the Golgi stacks were disorganized in Lis1-deficient liver cells. Of note, the Lis1 liver-knockout mice exhibited increased hepatocyte ploidy and accelerated development of liver cancer after exposure to the liver carcinogen diethylnitrosamine (DEN). Taken together, these findings suggest that reduced Lis1 levels can spur the development of liver diseases from steatosis to liver cancer and provide a useful model for delineating the molecular pathways that lead to these diseases.


Subject(s)
Classical Lissencephalies and Subcortical Band Heterotopias/genetics , Classical Lissencephalies and Subcortical Band Heterotopias/metabolism , Fatty Liver/genetics , Animals , Carcinoma, Hepatocellular/metabolism , Disease Models, Animal , Endoplasmic Reticulum Stress , Fatty Liver/metabolism , Hepatocytes/metabolism , Lipid Metabolism , Liver/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Mice , Mice, Knockout , Non-alcoholic Fatty Liver Disease/metabolism , Triglycerides/metabolism
6.
PLoS Pathog ; 12(4): e1005584, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27082114

ABSTRACT

The HTLV-1 oncoprotein Tax plays a key role in CD4+ T cell transformation by promoting cell proliferation and survival, mainly through permanent activation of the NK-κB pathway and induction of many NF-κB target genes. Elucidating the underlying molecular mechanism is therefore critical in understanding HTLV-1-mediated transformation. Current studies have suggested multiple but controversial mechanisms regarding Tax-induced IKK activation mainly due to blending of primary Tax-induced IKK activation events and secondary IKK activation events induced by cytokines secreted by the primary Tax-induced IKK-NF-κB activation events. We reconstituted Tax-stimulated IKK activation in a cell-free system to dissect the essential cellular components for primary IKK activation by Tax and studied the underlying biochemical mechanism. We found that Tax is a putative E3 ubiquitin ligase, which, together with UbcH2, UhcH5c, or UbcH7, catalyzes the assembly of free mixed-linkage polyubiquitin chains. These free mixed-linkage polyubiquitin chains are then responsible for direct IKK activation by binding to the NEMO subunit of IKK. Our studies revealed the biochemical function of Tax in the process of IKK activation, which utilizes the minimal cellular ubiquitination components for NF-κB activation.


Subject(s)
Enzyme Activation/physiology , Gene Products, tax/metabolism , HTLV-I Infections/metabolism , I-kappa B Kinase/metabolism , Polyubiquitin/biosynthesis , Ubiquitin-Protein Ligases/metabolism , Chromatography, High Pressure Liquid , Gene Knockout Techniques , HEK293 Cells , Humans , Immunoblotting , Jurkat Cells , NF-kappa B/metabolism , Signal Transduction/physiology , Tandem Mass Spectrometry , Transfection
7.
J Biol Chem ; 289(35): 24226-37, 2014 Aug 29.
Article in English | MEDLINE | ID: mdl-25028512

ABSTRACT

TGF-ß-activated kinase 1 (TAK1) is a key kinase in mediating Toll-like receptors (TLRs) and interleukin-1 receptor (IL-1R) signaling. Although TAK1 activation involves the phosphorylation of Thr-184 and Thr-187 residues at the activation loop, the molecular mechanism underlying the complete activation of TAK1 remains elusive. In this work, we show that the Thr-187 phosphorylation of TAK1 is regulated by its C-terminal coiled-coil domain-mediated dimerization in an autophosphorylation manner. Importantly, we find that TAK1 activation in mediating downstream signaling requires an additional phosphorylation at Ser-412, which is critical for TAK1 response to proinflammatory stimuli, such as TNF-α, LPS, and IL-1ß. In vitro kinase and shRNA-based knockdown assays reveal that TAK1 Ser-412 phosphorylation is regulated by cAMP-dependent protein kinase catalytic subunit α (PKACα) and X-linked protein kinase (PRKX), which is essential for proper signaling and proinflammatory cytokine induction by TLR/IL-1R activation. Morpholino-based in vivo knockdown and rescue studies show that the corresponding site Ser-391 in zebrafish TAK1 plays a conserved role in NF-κB activation. Collectively, our data unravel a previously unknown mechanism involving TAK1 phosphorylation mediated by PKACα and PRKX that contributes to innate immune signaling.


Subject(s)
Cyclic AMP-Dependent Protein Kinases/metabolism , MAP Kinase Kinase Kinases/metabolism , Protein Serine-Threonine Kinases/metabolism , Amino Acid Sequence , Animals , Catalytic Domain , Cell Line , Cyclic AMP-Dependent Protein Kinases/chemistry , Dimerization , Enzyme Activation , Humans , MAP Kinase Kinase Kinases/genetics , Mice , Molecular Sequence Data , Mutagenesis, Site-Directed , Phosphorylation , Sequence Homology, Amino Acid , Zebrafish
8.
Arthritis Rheum ; 65(7): 1872-81, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23576011

ABSTRACT

OBJECTIVE: Lupus flares occur when genetically predisposed individuals encounter appropriate environmental agents. Current evidence indicates that the environment contributes by inhibiting T cell DNA methylation, causing overexpression of normally silenced genes. DNA methylation depends on both dietary transmethylation micronutrients and ERK-regulated DNA methyltransferase 1 (DNMT-1) levels. We used transgenic mice to study the effect of interactions between diet, DNMT-1 levels, and genetic predisposition on the development and severity of lupus. METHODS: A doxycycline-inducible ERK defect was bred into lupus-resistant (C57BL/6) and lupus-susceptible (C57BL/6 × SJL) mouse strains. Doxycycline-treated mice were fed a standard commercial diet for 18 weeks and then switched to a transmethylation micronutrient-supplemented (MS) or -restricted (MR) diet. Disease severity was assessed by examining anti-double-stranded DNA (anti-dsDNA) antibody levels, the presence of proteinuria and hematuria, and by histopathologic analysis of kidney tissues. Pyrosequencing was used to determine micronutrient effects on DNA methylation. RESULTS: Doxycycline induced modest levels of anti-dsDNA antibodies in C57BL/6 mice and higher levels in C57BL/6 × SJL mice. Doxycycline-treated C57BL/6 × SJL mice developed hematuria and glomerulonephritis on the MR and standard diets but not the MS diet. In contrast, C57BL/6 mice developed kidney disease only on the MR diet. Decreasing ERK signaling and methyl donors also caused demethylation and overexpression of the CD40lg gene in female mice, consistent with demethylation of the second X chromosome. Both the dietary methyl donor content and the duration of treatment influenced methylation and expression of the CD40lg gene. CONCLUSION: Dietary micronutrients that affect DNA methylation can exacerbate or ameliorate disease in this transgenic murine lupus model, and contribute to lupus susceptibility and severity through genetic-epigenetic interactions.


Subject(s)
Antibodies, Antinuclear/immunology , DNA (Cytosine-5-)-Methyltransferases/metabolism , DNA Methylation/physiology , Diet , Lupus Erythematosus, Systemic/genetics , Micronutrients , Animals , Betaine , CD40 Ligand/metabolism , Choline , Coenzymes , DNA (Cytosine-5-)-Methyltransferase 1 , DNA Methylation/genetics , Disease Models, Animal , Epigenesis, Genetic , Folic Acid , Gene Silencing , Genetic Predisposition to Disease , Lupus Erythematosus, Systemic/immunology , Methionine , Mice , Mice, Inbred C57BL , Mice, Transgenic , Riboflavin , Vitamin B 12 , Vitamin B 6 , Zinc
9.
Pharmaceutics ; 16(6)2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38931926

ABSTRACT

Etomidate is a general anesthetic that has shown good hemodynamic stability without significant cardiovascular or respiratory depression. Despite several kinds of dosage forms having been reported for this drug, formulation types are very limited in clinical practice, and brain-targeted formulations for this central nervous system (CNS) drug have been rarely reported. Moreover, studies on the biocompatibility, toxicity, and anesthetic effects of the etomidate preparations in vivo were inadequate. The present study was to develop lactoferrin-modified liposomal etomidate (Eto-lip-LF) for enhanced drug distribution in the brain and improved anesthetic effects. Eto-lip-LF had good stability for storage and hemocompatibility for intravenous injection. Compared with the non-lactoferrin-containing liposomes, the lactoferrin-modified liposomes had notably enhanced brain-targeting ability in vivo, which was probably realized by the binding of transferrin with the transferrin and lactoferrin receptors highly distributed in the brain. Eto-lip-LF had a therapeutic index of about 25.3, higher than that of many other general anesthetics. Moreover, compared with the commercial etomidate emulsion, Eto-lip-LF could better achieve rapid onset of general anesthesia and rapid recovery from anesthesia, probably due to the enhanced drug delivery to the brain. The above results demonstrated the potential of this lactoferrin-modified liposomal etomidate to become an alternative preparation for clinical general anesthesia.

10.
Minerva Anestesiol ; 89(11): 1034-1041, 2023 11.
Article in English | MEDLINE | ID: mdl-37921198

ABSTRACT

INTRODUCTION: This meta-analysis aims to investigate the effect of dexmedetomidine (Dex) on postoperative cognitive dysfunction (POCD) in elderly patients undergoing abdominal surgery under general anesthesia. EVIDENCE ACQUISITION: Six online databases were searched for studies on the effects of Dex on POCD in elderly patients (≥60 years) who underwent abdominal surgery under general anesthesia. The experimental group was treated with Dex and the control group with normal saline. The retrieval period was from the database's inception to March 2023. Stata 15.0 statistical software was utilized to analyze the data. EVIDENCE SYNTHESIS: In total, 14 studies were entered into this meta-analysis, including 675 patients. On the first, third, and seventh days after surgery, the Mini-Mental State Examination (MMSE) scores in the experimental group were significantly higher than those in the controls (first day: weighted mean difference [WMD] = 2.52, 95% CI: 1.13~3.90, P<0.001; third day: WMD=2.58, 95% CI: 0.76~4.40, P=0.005; seventh day: WMD=1.43, 95% CI: 0.57~2.29, P=0.001). On the first day after surgery, there was a lot less cognitive dysfunction in the Dex group than in the controls (odds ratio [OR] = 0.25, 95% CI: 0.15~0.42, P<0.001). CONCLUSIONS: Dex administered intraoperatively can enhance early cognitive function in elderly patients undergoing abdominal surgery.


Subject(s)
Cognitive Dysfunction , Dexmedetomidine , Humans , Aged , Dexmedetomidine/adverse effects , Postoperative Complications/etiology , Cognitive Dysfunction/etiology , Cognition , Anesthesia, General/adverse effects
11.
J Pain Res ; 16: 2383-2392, 2023.
Article in English | MEDLINE | ID: mdl-37469957

ABSTRACT

Purpose: Adequate postoperative analgesia is a key to earlier recovery from open surgery. This work investigated the pain control and quality of patient recovery after hepatectomy to evaluate the modified continuous serratus anterior plane block (called low SAPB) for postoperative analgesia. Patients and Methods: This single-center, blinded, randomized, controlled study included 136 patients who underwent hepatectomy under general anesthesia. For postoperative analgesia, the patients in the SAPB group were given a continuous low SAPB at the 7th intercostal space in the right mid-axillary line, and the patients in the control group were given continuous intravenous opioid analgesia. The numeric pain rating scale (NPRS) was used for pain assessment. The postoperative assessment focused on the remedial drug consumption, the occurrence of adverse postoperative analgesic reactions, and the quality of patient recovery evaluated with the QoR-15 questionnaire. Results: Compared to the controls, the SAPB patients had significantly lower NPRS scores at 12 h and 24 h at rest and 6 h, 12 h, and 24 h in motion, and a longer time to first use of remedial analgesics at 24 h, and higher overall QoR-15 scores at 24 h [124 (121, 126) vs 121 (120, 124)] and 48 h [129 (126, 147) vs 126 (125, 128)], after surgery. There was no significant difference in the incidence of analgesia-related adverse reactions between the two groups. Conclusion: The continuous low SAPB could achieve superior pain control, especially for motor pain, to intravenous opioid analgesia during the first 24 h post-surgery. Even with no significant difference in the incidence of postoperative adverse reactions, patients with continuous low SAPB appeared to have a higher quality of recovery in the first two days post-surgery than patients with continuous intravenous analgesia.

12.
Cell Death Discov ; 9(1): 171, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37202386

ABSTRACT

Oncolytic viruses have recently been proven to be an effective and promising cancer therapeutic strategy, but there is rare data about oncolytic therapy in esophageal squamous cell carcinoma (ESCC), especially oncolytic measles virotherapy. Therefore, this study aimed to explore whether the recombinant measles virus vaccine strain rMV-Hu191 has an oncolytic effect against ESCC cells in vitro and in vivo and elucidate the underlying mechanisms. Our results showed that rMV-Hu191 could efficiently replicate in and kill ESCC cells through caspase-3/GSDME-mediated pyroptosis. Mechanistically, rMV-Hu191 triggers mitochondrial dysfunction to induce pyroptosis, which is mediated by BAK (BCL2 antagonist/killer 1) or BAX (BCL2 associated X). Further analysis revealed that rMV-Hu191 activates inflammatory signaling in ESCC cells, which may enhance the oncolytic efficiency. Moreover, intratumoral injection of rMV-Hu191 induced dramatic tumor regression in an ESCC xenograft model. Collectively, these findings imply that rMV-Hu191 exhibits an antitumor effect through BAK/BAX-dependent caspase-3/GSDME-mediated pyroptosis and provides a potentially promising new therapy for ESCC treatment.

13.
ACS Omega ; 8(34): 31529-31540, 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37663478

ABSTRACT

This study aimed to investigate the active ingredients and therapeutic mechanisms of Jingu Tongxiao Pill (JGTXP), a commonly used Chinese patent medicine, in treating osteoarthritis (OA) via network pharmacology analysis combined with experimental validation. First, we administered JGTXP to rat plasma and identified the candidate active compounds. Next, target prediction, protein-protein interaction, compound-target network construction, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were conducted for JGTXP. Lastly, the network-derived key targets and pathways were validated in vitro and in vivo. Finally, we identified 106 compounds in JGTXP and 24 absorbed compounds in the rat plasma. Network analysis revealed that JGTXP interferes with OA mainly via regulating the inflammatory response, collagen catabolic process, and osteoclast differentiation, and the nuclear factor kappa B (NF-κB) signaling pathway plays a pivotal role in these processes. Experimentally, JGTXP exerted potential protective effects on articular cartilage and inhibited expression of inflammatory mediators and collagen catabolism-related proteins, including interleukin 1 beta (IL-1ß), interleukin 6, tumor necrosis factor alpha (TNF-α), and matrix metalloproteinase (MMP) 3 and MMP13, in a papain-induced OA rat model. Consistently, mRNA expression levels of these factors and nitric oxide release were suppressed by JGTXP in an LPS-induced RAW 264.7 inflammation model. The reporter gene assay showed that JGTXP could reduce the transcriptional activity of NF-κB. Consecutive western blot analysis demonstrated that nuclear NF-κB p65, inducible nitric oxide synthase (iNOS), and cyclooxygenase 2 (COX-2) expression were inhibited while cytoplasmic NF-κB p65 was upregulated by JGTXP. Using a combination of chemical profiling, network pharmacology analysis, and experimental validation, we preliminarily clarified the active ingredients of JGTXP intervention for OA and demonstrated that JGTXP ameliorates OA, at least partially, by regulating the NF-κB signaling pathway.

14.
Int J Pharm ; 638: 122929, 2023 May 10.
Article in English | MEDLINE | ID: mdl-37028570

ABSTRACT

Dihydromyricetin (DHM) is an important natural flavonoid. However, most of DHM preparations have shown shortcomings such as low drug loading, poor drug stability, and/or large fluctuations in blood concentration. This study aimed to develop a gastric floating tablet with a double-layered structure for zero-order controlled release of DHM (DHM@GF-DLT). The final product DHM@GF-DLT showed a high average cumulative drug release at 24 h that best fit the zero-order model, and had a good floating ability in the stomach of the rabbit with a gastric retention time of over 24 h. The FTIR, DSC, and XRPD analyses indicated the good compatibility among the drug and the excipients in DHM@GF-DLT. The pharmacokinetic study revealed that DHM@GF-DLT could prolong the retention time of DHM, reduce the fluctuation of blood drug concentration, and enhance the bioavailability of DHM. The pharmacodynamic studies demonstrated that DHM@GF-DLT had a potent and long-term therapeutic effect on systemic inflammation in rabbits. Therefore, DHM@GF-DLT had the potential to serve as a promising anti-inflammatory agent and may develop into a once-a-day preparation, which was favorable to maintain a steady blood drug concentration and a long-term drug efficacy. Our research provided a promising development strategy for DHM and other natural products with a similar structure to DHM for improving their bioavailability and therapeutic effect.


Subject(s)
Flavonols , Stomach , Animals , Rabbits , Delayed-Action Preparations/chemistry , Tablets/chemistry
15.
Front Pharmacol ; 14: 1176980, 2023.
Article in English | MEDLINE | ID: mdl-37701040

ABSTRACT

Purpose: To conduct a real-world evaluation of the efficacy and safety of combined Chinese and Western medicine in treating knee osteoarthritis (KOA). Methods: A multicenter, prospective cohort study design was employed, enrolling 450 KOA patients (Kellgren-Lawrence score of 3 or less). The patients were divided into a Western medicine treatment group (WM group) and a combined Western and traditional Chinese medicine treatment group (WM-CM group). A 6-week treatment plan was administered, and follow-up visits occurred at 2 weeks, 4 weeks, and 6 weeks after initiating treatment. The primary outcome indicator was the total Western Ontario and McMaster Universities Arthritis Index (WOMAC) score after 6 weeks of treatment. Secondary outcome indicators included WOMAC subscales for pain, stiffness, and joint function, visual analogue scale (VAS) score, physical component summary (PCS), mental component summary (MCS), and clinical effectiveness. The incidence of drug-related adverse events was used as a safety evaluation indicator. Results: A total of 419 patients were included in the final analysis: 98 in the WM group and 321 in the WM-CM group. The baseline characteristics of the two groups were comparable, except for the incidence of stiffness symptoms and stiffness scores. After 6 weeks of treatment, the WM-CM group exhibited superior results to the WM group in improving the total WOMAC score (24.71 ± 1.38 vs. 16.36 ± 0.62, p < 0.001). The WM-CM group also outperformed the WM group in WOMAC pain and joint function scores, VAS score, PCS score, MCS score, and clinical effectiveness (p < 0.05), which was consistent with the findings of the main evaluation index. Subgroup analysis indicated that the combined Chinese and Western medicine treatment showed more pronounced benefits in patients under 65 years of age and in those with a Kellgren-Lawrence (K-L) classification of 0-I. Throughout the study, no adverse effects were observed in either group. Conclusion: The combination of Chinese and Western medicine demonstrated superiority over Western medicine alone in relieving knee pain symptoms, improving knee function, and enhancing the quality of life for KOA patients with a K-L score of 3 or less. Moreover, the treatment exhibited a good safety profile. Clinical Trial Registration: (https://www.chictr.org.cn/), identifier (ChiCTR1900027175).

16.
J Autoimmun ; 38(2-3): J135-43, 2012 May.
Article in English | MEDLINE | ID: mdl-22142890

ABSTRACT

Systemic lupus erythematosus (SLE) is an autoimmune disease primarily afflicting women. The reason for the gender bias is unclear, but genetic susceptibility, estrogen and environmental agents appear to play significant roles in SLE pathogenesis. Environmental agents can contribute to lupus susceptibility through epigenetic mechanisms. We used (C57BL/6xSJL)F1 mice transgenic for a dominant-negative MEK (dnMEK) that was previously shown to be inducibly and selectively expressed in T cells. In this model, induction of the dnMEK by doxycycline treatment suppresses T cell ERK signaling, decreasing DNA-methyltransferase expression and resulting in DNA demethylation, overexpression of immune genes Itgal (CD11a) and Tnfsf7 (CD70), and anti-dsDNA antibody. To examine the role of gender and estrogen in this model, male and female transgenic mice were neutered and implanted with time-release pellets delivering placebo or estrogen. Doxycycline induced IgG anti-dsDNA antibodies in intact and neutered, placebo-treated control female but not male transgenic mice. Glomerular IgG deposits were also found in the kidneys of female but not male transgenic mice, and not in the absence of doxycycline. Estrogen enhanced anti-dsDNA IgG antibodies only in transgenic, ERK-impaired female mice. Decreased ERK activation also resulted in overexpression and demethylation of the X-linked methylation-sensitive gene CD40lg in female but not male mice, consistent with demethylation of the second X chromosome in the females. The results show that both estrogen and female gender contribute to the female predisposition in lupus susceptibility through hormonal and epigenetic X-chromosome effects and through suppression of ERK signaling by environmental agents.


Subject(s)
Epigenesis, Genetic , Estrogens/toxicity , Gene-Environment Interaction , Lupus Erythematosus, Systemic/genetics , X Chromosome , Animals , Antibodies, Antinuclear/blood , Antibodies, Antinuclear/immunology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , DNA Methylation , Disease Models, Animal , Environmental Exposure , Female , Gene Expression , Lupus Erythematosus, Systemic/etiology , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/pathology , Lupus Nephritis/immunology , Lupus Nephritis/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Sex Factors
17.
Front Psychol ; 13: 991009, 2022.
Article in English | MEDLINE | ID: mdl-36046403

ABSTRACT

Online traveling community is initiated by companies, but its survival is inextricably linked to consumer citizenship behavior (e.g., out-group recommendation, in-group helping, and inward response). The majority of researches have investigated consumer behavior of brand community such as consumer satisfaction, brand loyalty, and purchase intention. A few scholars try to explore consumer behaviors beyond the purchase, like participation, which was concerned as the value co-creation. However, the value co-creation of the community should depend on consumers' citizenship behaviors instead of their pure participation. Therefore, this study empirically examines the effect of consumer interaction on consumer psychology and citizenship behaviors of the online travel community. The findings demonstrated that consumer interaction facilitated participants' self-identity and their perceived social support, which enhanced their community identification and thus their citizenship behaviors. Furthermore, the motivation of participation plays a moderator in this process. Specifically, symbolic motivation moderates the relationship between consumer interaction and their self-identity, while utilitarian motivation moderates the effect of consumer interaction on their perceived social support. These findings contributed to the intervention of consumer citizenship behavior in online traveling community and provide insights into the management of the online travel community from the perspective of the value co-creation.

18.
Radiat Res ; 197(5): 480-490, 2022 05 01.
Article in English | MEDLINE | ID: mdl-35172004

ABSTRACT

Radiation-induced esophageal injury (RIEI) is a major dose-limiting complication of radiotherapy, especially for esophageal and thoracic cancers. RIEI is a multi-factorial and multi-step process, which is regulated by a complex network of DNA, RNA, protein and metabolite. However, it is unclear which esophageal metabolites are altered by ionizing radiation and how these changes affect RIEI progression. In this work, we established a rat model of RIEI with 0-40 Gy X-ray irradiation. Esophageal irradiation using ≥25 Gy induced significant changes to rats, such as body weight, food intake, water intake and esophageal structure. The metabolic changes and related pathways of rat esophageal metabolites were investigated by liquid chromatography-mass spectrometry (LC-MS). One hundred eighty metabolites showed an up-regulation in a dose-dependent manner (35 Gy ≥ 25 Gy > controls), and 199 metabolites were downregulated with increasing radiation dose (35 Gy ≤ 25 Gy < controls). The KEGG analysis showed that ionizing radiation seriously disrupted multiple metabolic pathways, and arachidonic acid metabolism was the most significantly enriched pathway. 20 metabolites were dysregulated in arachidonic acid metabolism, including up-regulation of five prostaglandins (PGA2, PGJ2, PGD2, PGH2, and PGI2) in 25 or 35 Gy groups. Cyclooxygenase-2 (COX-2), the key enzyme in catalyzing the biosynthesis of prostaglandins from arachidonic acid, was highly expressed in the esophagus of irradiated rats. Additionally, receiver operating characteristic (ROC) curve analysis revealed that PGJ2 may serve as a promising tissue biomarker for RIEI diagnosis. Taken together, these findings indicate that ionizing radiation induces esophageal metabolic alterations, which advance our understanding of the pathophysiology of RIEI from the perspective of metabolism.


Subject(s)
Cyclooxygenase 2/metabolism , Metabolomics , Radiation Injuries , Animals , Arachidonic Acid/chemistry , Arachidonic Acid/metabolism , Esophagus/metabolism , Prostaglandins , Radiation Injuries/etiology , Rats
19.
Int J Nanomedicine ; 17: 227-244, 2022.
Article in English | MEDLINE | ID: mdl-35068931

ABSTRACT

INTRODUCTION: (-)-Gossypol (AT-101), the (-)-enantiomer of the natural compound gossypol, has shown significant inhibitory effects on various types of cancers such as osteosarcoma, myeloma, glioma, lung cancer, and prostate cancer. However, the clinical application of (-)-gossypol was often hindered by its evident side effects and the low bioavailability via oral administration, which necessitated the development of suitable (-)-gossypol preparations to settle the problems. In this study, injectable cyclic RGD (cRGD)-decorated liposome (cRGD-LP) was prepared for tumor-targeted delivery of (-)-gossypol. METHODS: The cRGD-LP was prepared based on cRGD-modified lipids. For comparison, a non-cRGD-containing liposome (LP) with a similar chemical composition to cRGD-LP was specially designed. The physicochemical properties of (-)-gossypol-loaded cRGD-LP (Gos/cRGD-LP) were investigated in terms of the drug loading efficiency, particle size, morphology, drug release, and so on. The inhibitory effect of Gos/cRGD-LP on the proliferation of tumor cells in vitro was evaluated using different cell lines. The biodistribution of cRGD-LP in vivo was investigated via the near-infrared (NIR) fluorescence imaging technique. The antitumor effect of Gos/cRGD-LP in vivo was evaluated in PC-3 tumor-bearing nude mice. RESULTS: Gos/cRGD-LP had an average particle size of about 62 nm with a narrow size distribution, drug loading efficiency of over 90%, and sustained drug release for over 96 h. The results of NIR fluorescence imaging demonstrated the enhanced tumor targeting of cRGD-LP in vivo. Moreover, Gos/cRGD-LP showed a significantly enhanced inhibitory effect on PC-3 tumors in mice, with a tumor inhibition rate of over 74% and good biocompatibility. CONCLUSION: The incorporation of cRGD could significantly enhance the tumor-targeting effect of the liposomes and improve the antitumor effect of the liposomal (-)-gossypol in vivo, which indicated the potential of Gos/cRGD-LP that warrants further investigation for clinical applications of this single-isomer drug.


Subject(s)
Gossypol , Liposomes , Animals , Cell Line, Tumor , Gossypol/analogs & derivatives , Male , Mice , Mice, Nude , Peptides, Cyclic , Tissue Distribution
20.
MedComm (2020) ; 3(3): e168, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36051984

ABSTRACT

Radiation-induced intestinal injury is a serious concern during abdominal and pelvic cancers radiotherapy. Ubiquitin (Ub) is a highly conserved protein found in all eukaryotic cells. This study aims to explore the role and mechanism of free Ub against radiogenic intestinal injury. We found that free Ub levels of irradiated animals and human patients receiving radiotherapy were upregulated. Radiation-induced Ub expression was associated with the activation of interferon regulatory factor 1 (IRF1). Intraperitoneal injection of free Ub significantly reduced the mortality of mice following 5-9 Gy total body irradiation (TBI) through the Akt pathway. Free Ub facilitates small intestinal regeneration induced by TBI or abdominal irradiation. At the cellular level, free Ub or its mutants significantly alleviated cell death and enhanced the survival of irradiated intestinal epithelial cells. The radioprotective role of free Ub depends on its receptor CXCR4. Mechanistically, free Ub increased fibroblast growth factor-2 (FGF2) secretion and consequently activated FGFR1 signaling following radiation in vivo and in vivo. Thus, free Ub confers protection against radiation-induced intestinal injury through CXCR4/Akt/FGF2 axis, which provides a novel therapeutic option.

SELECTION OF CITATIONS
SEARCH DETAIL