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1.
Front Immunol ; 14: 1255799, 2023.
Article in English | MEDLINE | ID: mdl-37731507

ABSTRACT

New York-esophageal cancer 1 (NY-ESO-1) belongs to the cancer testis antigen (CTA) family, and has been identified as one of the most immunogenic tumor-associated antigens (TAAs) among the family members. Given its ability to trigger spontaneous humoral and cellular immune response and restricted expression, NY-ESO-1 has emerged as one of the most promising targets for cancer immunotherapy. Cancer vaccines, an important element of cancer immunotherapy, function by presenting an exogenous source of TAA proteins, peptides, and antigenic epitopes to CD4+ T cells via major histocompatibility complex class II (MHC-II) and to CD8+ T cells via major histocompatibility complex class I (MHC-I). These mechanisms further enhance the immune response against TAAs mediated by cytotoxic T lymphocytes (CTLs) and helper T cells. NY-ESO-1-based cancer vaccines have a history of nearly two decades, starting from the first clinical trial conducted in 2003. The current cancer vaccines targeting NY-ESO-1 have various types, including Dendritic cells (DC)-based vaccines, peptide vaccines, protein vaccines, viral vaccines, bacterial vaccines, therapeutic whole-tumor cell vaccines, DNA vaccines and mRNA vaccines, which exhibit their respective benefits and obstacles in the development and application. Here, we summarized the current advances in cancer vaccines targeting NY-ESO-1 for solid cancer treatment, aiming to provide perspectives for future research.


Subject(s)
Cancer Vaccines , Neoplasms , Male , Humans , CD8-Positive T-Lymphocytes , Antibodies , Immunotherapy , Bacterial Vaccines , Neoplasms/therapy
2.
Front Endocrinol (Lausanne) ; 13: 952918, 2022.
Article in English | MEDLINE | ID: mdl-36237188

ABSTRACT

Objective: This study aimed to identify potential biomarkers associated with the occurrence of minor ischaemic stroke. Methods: Four hundred patients hospitalized with minor ischaemic stroke were enrolled in the department of neurological internal medicine in Taiyuan Central Hospital, and 210 healthy subjects examined at the Taiyuan Central Hospital Medical Center during the same period were selected. We collected information on the general demographic characteristics and fasting blood samples of the subjects. We then used untargeted metabolomic assay to measure blood glucose, blood lipids, homocysteine, and high-sensitivity C-reactive protein. Results: There were statistically significant differences between the mild ischemic stroke group and the healthy control group in smoking, hypertension, and physical activity (P< 0.05). Compared with the healthy group, the minor ischaemic stroke group showed increased lactate, pyruvate, trimetlylamine oxide levels, and lactic acid, pyruvic acid, and trimethylamine N-oxidation (TMAO) levels were statistically significant (P< 0.001). In the minor ischaemic stroke risk model, hypertension, physical activity, smoking, and elevated TMAO levels influenced the occurrence of minor stroke. Conclusion: Increased levels of lactic acid, pyruvate, and TMAO may be related to the pathophysiological changes in the minor ischaemic stroke population. High blood pressure, a lack of physical activity, smoking, and increased TMAO level were the influencing factors for the occurrence of minor ischaemic stroke. The serum metabolite TMAO may be associated with MS occurrence.


Subject(s)
Brain Ischemia , Hypertension , Ischemic Stroke , Stroke , Biomarkers , Blood Glucose , Brain Ischemia/complications , C-Reactive Protein , Homocysteine , Humans , Hypertension/complications , Lactic Acid , Methylamines , Oxides , Pyruvic Acid
3.
Int Immunopharmacol ; 112: 109283, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36201943

ABSTRACT

BACKGROUND: Coronavirus disease 2019 (COVID-19) continues to be a major global public health challenge, with the emergence of variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Current vaccines or monoclonal antibodies may not well be protect against infection with new SARS-CoV-2 variants. Unlike antibody-based treatment, T cell-based therapies such as TCR-T cells can target epitopes that are highly conserved across different SARS-CoV-2 variants. Reportedly, T cell-based immunity alone can restrict SARS-CoV-2 replication. METHODS: In this study, we identified two TCRs targeting the RNA-dependent RNA polymerase (RdRp) protein in CD8 + T cells. Functional evaluation by transducing these TCRs into CD8 + or CD4 + T cells confirmed their specificity. RESULTS: Combinations of inflammatory and anti-inflammatory cytokines secreted by CD8 + and CD4 + T cells can help control COVID-19 in patients. Moreover, the targeted epitope is highly conserved in all emerged SARS-CoV-2 variants, including the Omicron. It is also conserved in the seven coronaviruses that infect humans and more broadly in the subfamily Coronavirinae. CONCLUSIONS: The pan-genera coverage of mutant epitopes from the Coronavirinae subfamily by the two TCRs highlights the unique strengths of TCR-T cell therapies in controlling the ongoing pandemic and in preparing for the next coronavirus outbreak.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/genetics , COVID-19/therapy , Epitopes , Receptors, Antigen, T-Cell/genetics , Antibodies, Monoclonal/therapeutic use , RNA-Dependent RNA Polymerase , Cytokines , Epitopes, T-Lymphocyte/genetics
4.
Parkinsons Dis ; 2022: 6813017, 2022.
Article in English | MEDLINE | ID: mdl-35873704

ABSTRACT

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder for which no effective treatment is available. Studies have demonstrated that improving insulin resistance in type 2 diabetes mellitus (T2DM) can benefit patients with PD. In addition, a neuroprotective effect of glucagon-like peptide-1 (GLP-1) receptor agonists was demonstrated in experimental models of PD. In addition, there are some clinical trials to study the neuroprotective effect of GLP-1 analog on PD patients. Semaglutide is a long-acting, once-a-week injection treatment and the only available oral form of GLP-1 analog. In the present study, we treated the human neuroblastoma SH-SY5Y cell line with 6-hydroxydopamine (6-OHDA) as a PD in vitro model to explore the neuroprotective effects and potential mechanisms of semaglutide to protect against PD. Moreover, we compared the effect of semaglutide with liraglutide given at the same dose. We demonstrated that both semaglutide and liraglutide protect against 6-OHDA cytotoxicity by increasing autophagy flux and decreasing oxidative stress as well as mitochondrial dysfunction in SH-SY5Y cells. Moreover, by comparing the neuroprotective effects of semaglutide and liraglutide on PD cell models at the same dose, we found that semaglutide was superior to liraglutide for most parameters measured. Our results indicate that semaglutide, the new long-acting and only oral GLP-1 analog, may be represent a promising treatment for PD.

5.
J Immunol Methods ; 504: 113260, 2022 05.
Article in English | MEDLINE | ID: mdl-35331733

ABSTRACT

T-cell receptor (TCR)-transduced T (TCR-T) cell therapy has shown promising efficacy in the clinical treatment of malignant cancers. However, the populations covered by reported TCRs are still limited. Tumor infiltrating lymphocytes (TILs) are natural reservoirs of tumor-reactive T cells and TCRs. Approaches are required for the fast and cost-effective identification of tumor-reactive TCRs from TILs. The widely employed TCR identification approaches by the clonal expansion of TILs involve a TCR singularization process for the direct pairing of TCR Vα and the Vß chain. However, the clonal expansion of T cells is well known to require extensive time and effort due to the involvement of T cell cultures. Several single-cell multiplexing PCR methods followed by Sanger sequencing have been developed, representing a cost-effective and fast approach for single-cell TCR identification. In this study, an RNA-based preamplification step was included in the single-cell TCR sequencing, which can reduce the multiplexing PCR amplification to one round. Moreover, the cDNA product of RNA preamplification is derived from the whole genome mRNA, instead of TCR mRNA only by multiplexing primers-based DNA preamplification, which is valuable for many other analyses (e.g., phenotypic analysis) of the tumor-reactive T cells that can be correlated with the identified TCRs. The feasibility for both single α chain and dual α chain TILs of this approach highlights its potential value as a rapid and cost-effective sequencing strategy for the development of TCR-T therapies for solid cancers.


Subject(s)
Neoplasms , Receptors, Antigen, T-Cell , Humans , Lymphocytes, Tumor-Infiltrating , RNA , RNA, Messenger/genetics , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell, alpha-beta/genetics
6.
BMC Immunol ; 22(1): 65, 2021 09 28.
Article in English | MEDLINE | ID: mdl-34583647

ABSTRACT

Adoptive transfer of T cells genetically engineered with a T cell receptor (TCR) is a promising cancer treatment modality that requires the identification of TCRs with good characteristics. Most T cell cloning methods involve a stringent singularization process, which necessitates either tedious hands-on operations or high cost. We present an efficient and nonstringent cloning approach based on existing techniques. We hypothesize that after elimination of most nonspecific T cells, a clonotype with high quality could outcompete other clonotypes and finally form a predominant population. This TCR identification method can be used to clone virus-specific TCRs efficiently from cancer patients and is easily adoptable by any laboratory.


Subject(s)
Immunotherapy, Adoptive/methods , Neoplasms/immunology , Neoplasms/therapy , Oncogenic Viruses/physiology , Receptors, Antigen, T-Cell/metabolism , T-Lymphocytes/immunology , Virus Diseases/immunology , Cell Line , Clone Cells , Flow Cytometry , High-Throughput Nucleotide Sequencing , Humans , Receptors, Antigen, T-Cell/genetics , T-Lymphocytes/transplantation
7.
Hepatol Commun ; 5(6): 1106-1119, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34141993

ABSTRACT

Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) remains a global health concern, and HBV proteins may be ideal targets for T cell-based immunotherapy for HCC. There is a need for fast and efficient identification of HBV-specific T cell receptors (TCRs) for the development of TCR-transduced T (TCR-T) cell-based immunotherapy. Two widely employed TCR identification approaches, T cell clonal expansion and single-cell sequencing, involve a TCR singularization process for the direct identification of Vα and Vß pairs of TCR chains. Clonal expansion of T cells is well known to have tedious time and effort requirements due to the use of T cell cultures, whereas single-cell sequencing is limited by the requirements of cell sorting and the preparation of a single-cell immune-transcriptome library as well as the massive cost of the whole procedure. Here, we present a next-generation sequencing (NGS)-based HBV-specific TCR identification that does not require the TCR singularization process. Conclusion: Two pairing strategies, ranking-based strategy and α-ß chain mixture-based strategy, have proved to be useful for NGS-based TCR identification, particularly for polyclonal T cells purified by a peptide-major histocompatibility complex (pMHC) multimer-based approach. Functional evaluation confirmed the specificity and avidity of two identified HBV-specific TCRs, which may potentially be used to produce TCR-T cells to treat patients with HBV-related HCC.

8.
J Infect Dis ; 224(6): 956-966, 2021 09 17.
Article in English | MEDLINE | ID: mdl-34145459

ABSTRACT

BACKGROUND: Coronavirus disease 2019 (COVID-19) continues to be a major public health challenge globally. The identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-derived T-cell epitopes is of critical importance for peptide vaccines or diagnostic tools of COVID-19. METHODS: In this study, several SARS-CoV-2-derived human leukocyte antigen (HLA)-I binding peptides were predicted by NetMHCpan-4.1 and selected by Popcover to achieve pancoverage of the Chinese population. The top 5 ranked peptides derived from each protein of SARS-CoV-2 were then evaluated using peripheral blood mononuclear cells from unexposed individuals (negative for SARS-CoV-2 immunoglobulin G). RESULTS: Seven epitopes derived from 4 SARS-CoV-2 proteins were identified. It is interesting to note that most (5 of 7) of the SARS-CoV-2-derived peptides with predicted affinities for HLA-I molecules were identified as HLA-II-restricted epitopes and induced CD4+ T cell-dependent responses. These results complete missing pieces of pre-existing SARS-CoV-2-specific T cells and suggest that pre-existing T cells targeting all SARS-CoV-2-encoded proteins can be discovered in unexposed populations. CONCLUSIONS: In summary, in the current study, we present an alternative and effective strategy for the identification of T-cell epitopes of SARS-CoV-2 in healthy subjects, which may indicate an important role in the development of peptide vaccines for COVID-19.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , COVID-19/prevention & control , Epitopes, T-Lymphocyte/immunology , Vaccines, Subunit/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cell Line , Humans , Leukocytes, Mononuclear/immunology , SARS-CoV-2
9.
Immunopharmacol Immunotoxicol ; 42(4): 319-329, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32419542

ABSTRACT

AIM: Adoptive cell therapy (ACT) of tumor-infiltrating lymphocytes (TILs) has demonstrated clinical benefits in metastatic melanoma treatment. However, the clinical application of TILs produced by a widely used standard protocol from non-small cell lung cancer (NSCLC) can be quite challenging because of the limited clinical benefits. A comprehensive phenotypic knowledge of TILs obtained from NSCLC is important for the development and improvement of personalized TIL therapy for NSCLC patients. METHODS: In this study, we successfully expanded TILs from 141 NSCLC tissues which can be used in clinical ACT after expansion by a rapid expansion protocol (REP). RESULTS: Our study indicates that the clinicopathological characteristics of patients have considerable impacts on the phenotype of in vitro TIL culture products. Different culture conditions are necessary for patients with different clinical features. Specific manipulations before REP expansion are required depending on the different phenotypes of TIL cultures (e.g. depletion of immune-suppressive γδT cells). With these optimizations, next-generation TIL therapy may become a treatment alternative for NSCLC patients in the future.


Subject(s)
Carcinoma, Non-Small-Cell Lung/immunology , Immunotherapy, Adoptive/methods , Lung Neoplasms/immunology , Lymphocytes, Tumor-Infiltrating/immunology , Phenotype , Adult , Aged , Aged, 80 and over , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/therapy , Female , Humans , Lung Neoplasms/pathology , Lung Neoplasms/therapy , Lymphocytes, Tumor-Infiltrating/pathology , Male , Middle Aged , Tumor Cells, Cultured
10.
PLoS Biol ; 17(6): e3000281, 2019 06.
Article in English | MEDLINE | ID: mdl-31185007

ABSTRACT

Rhino- and enteroviruses are important human pathogens, against which no antivirals are available. The best-studied inhibitors are "capsid binders" that fit in a hydrophobic pocket of the viral capsid. Employing a new class of entero-/rhinovirus inhibitors and by means of cryo-electron microscopy (EM), followed by resistance selection and reverse genetics, we discovered a hitherto unknown druggable pocket that is formed by viral proteins VP1 and VP3 and that is conserved across entero-/rhinovirus species. We propose that these inhibitors stabilize a key region of the virion, thereby preventing the conformational expansion needed for viral RNA release. A medicinal chemistry effort resulted in the identification of analogues targeting this pocket with broad-spectrum activity against Coxsackieviruses B (CVBs) and compounds with activity against enteroviruses (EV) of groups C and D, and even rhinoviruses (RV). Our findings provide novel insights in the biology of the entry of entero-/rhinoviruses and open new avenues for the design of broad-spectrum antivirals against these pathogens.


Subject(s)
Capsid Proteins/ultrastructure , Capsid/drug effects , Capsid/ultrastructure , Amino Acid Sequence/genetics , Amino Acids/genetics , Antigens, Viral , Antiviral Agents , Binding Sites , Capsid/metabolism , Capsid Proteins/metabolism , Cryoelectron Microscopy/methods , Drug Development/methods , Enterovirus/drug effects , Enterovirus/ultrastructure , Humans , Models, Molecular , Molecular Conformation , Rhinovirus/drug effects , Rhinovirus/ultrastructure , Viral Proteins/chemistry , Viral Proteins/ultrastructure , Virion/genetics
11.
Int J Antimicrob Agents ; 53(2): 128-136, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30063999

ABSTRACT

Human enterovirus 71 (EV-A71) infections cause a wide array of diseases ranging from diarrhoea and rashes to hand-foot-and-mouth disease and, in rare cases, severe neurological disorders. No specific antiviral drug therapy is currently available. Extracts from 75 Chinese medicinal plants selected for antiviral activity based on the Chinese pharmacopeia and advice from traditional Chinese medicine clinicians were tested for activity against EV-A71. The aqueous extract of the rhizome of Cimicifuga heracleifolia (Sheng Ma) and Arnebia euchroma (Zi Cao) showed potent antiviral activity. The active fractions were isolated by bioassay-guided purification, and identified by a combination of high-resolution mass spectrometry and nuclear magnetic resonance. Fukinolic acid and cimicifugic acid A and J, were identified as active anti-EV-A71 compounds for C. heracleifolia, whereas for A. euchroma, two caffeic acid derivatives were tentatively deduced. Commercially available fukinolic acid analogues such as L-chicoric acid and D-chicoric also showed in vitro micromolar activity against EV-A71 lab-strain and clinical isolates.


Subject(s)
Antiviral Agents/pharmacology , Boraginaceae/chemistry , Caffeic Acids/pharmacology , Cimicifuga/chemistry , Enterovirus A, Human/drug effects , Phenylacetates/pharmacology , Plant Extracts/pharmacology , Succinates/pharmacology , 3C Viral Proteases , Cysteine Endopeptidases , Enterovirus A, Human/isolation & purification , Enterovirus Infections/drug therapy , Enterovirus Infections/virology , Humans , Mass Spectrometry , Medicine, Chinese Traditional , Microbial Sensitivity Tests , Nuclear Magnetic Resonance, Biomolecular , Viral Proteins/antagonists & inhibitors , Virus Replication/drug effects
12.
Antiviral Res ; 162: 51-53, 2019 02.
Article in English | MEDLINE | ID: mdl-30550798

ABSTRACT

Parechoviruses A (HPeV, Picornaviridae) are neglected human pathogens that cause sepsis-like illness and severe neurological complications in infants. There are no antivirals available for the treatment of HPeV infections. We here report on cell-based assays that allow for medium-throughput antiviral screening of compound libraries against HPeV. The nucleoside viral polymerase inhibitor 2'-C-methylcytidine was identified as being an in vitro replication inhibitor of HPeV1 and HPeV3 that can serve as a reference molecule for further antiviral studies.


Subject(s)
Antiviral Agents/pharmacology , Nucleosides/pharmacology , Parechovirus/drug effects , A549 Cells , Animals , Antiviral Agents/chemistry , Chlorocebus aethiops , HeLa Cells , High-Throughput Screening Assays , Humans , Mice , Parechovirus/physiology , Vero Cells , Virus Replication/drug effects
13.
Antiviral Res ; 147: 67-74, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28993161

ABSTRACT

4-dimethylamino benzoic acid (compound 12, synonym: 4EDMAB) was identified as an in vitro inhibitor of Coxsackie virus B3 (CVB3) replication in CPE-based assays (EC50 of 9.1 ± 1.5 µM). Next, the activity of twenty-three analogues was assessed, their structure-activity relationship was deduced and a more potent analogue was identified (EC50 of 2.6 ± 0.5 µM). The antiviral activity of 4EDMAB was further confirmed by quantifying viral RNA yield. Time-of-drug-addition assay revealed that 4EDMAB exerts its antiviral activity at the early stages of virus replication. Six compound-resistant viruses were selected and genotyped and all the mutations appeared to be in the capsid protein VP1. Reverse engineering showed that single mutants Y75C, A88V, A98V, D133N and R219K were respectively 15-, 2-, 4-, 17- and 76-fold resistant to 4EDMAB. The compound protected both wild type (WT) CVB3 and the five resistant mutants from heat inactivation. The plaque size produced by the A88V, D133N and R219K mutants was smaller than that of WT and these mutants were also more heat-sensitive than WT in the absence of the compound. These findings suggest that these three mutations increase virion capsid flexibility and compensate for the stabilizing effects of 4EDMAB. Molecular modelling suggests that the compound binds to a small cavity in VP1, which is different from the hydrophobic pocket in the canyon where typical capsid binders (such as pleconaril) bind. Modelling studies also suggest a direct ionic interaction between the negatively charged carboxylic group of 4EDMAB and the positively charged guanidino group of arginine 219. Moreover, the in vitro combination of 4EDMAB and pleconaril resulted in synergistic antiviral effect. In conclusion, 4EDMAB is a novel early-stage inhibitor, which targets VP1 with a mechanism that is different from that of known capsid binders.


Subject(s)
Capsid Proteins/antagonists & inhibitors , Enterovirus B, Human/drug effects , Virus Replication/drug effects , para-Aminobenzoates/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Capsid/drug effects , Capsid Proteins/chemistry , Capsid Proteins/genetics , Capsid Proteins/metabolism , Cell Line , Cytopathogenic Effect, Viral/drug effects , Drug Resistance, Viral/genetics , Drug Synergism , Enterovirus B, Human/genetics , Enterovirus Infections/drug therapy , Genotype , Humans , Molecular Conformation , Molecular Docking Simulation , Oxadiazoles/pharmacology , Oxadiazoles/therapeutic use , Oxazoles , Protein Binding , RNA, Viral/genetics , Structure-Activity Relationship , para-Aminobenzoates/chemistry , para-Aminobenzoates/therapeutic use
14.
Acta Biochim Biophys Sin (Shanghai) ; 49(4): 318-327, 2017 Apr 01.
Article in English | MEDLINE | ID: mdl-28338809

ABSTRACT

Recent studies revealed that sirtuin 1 (SIRT1) is involved in the regulation of energy metabolism and its agonist resveratrol showed anti-obesity effect. This study aims to determine whether BTM-0512, a novel derivative of resveratrol, acts as an antagonist of obesity and to explore its possible mechanisms. High-fat diet (HFD)-induced obese mice were intragastrically administered with BTM-0512 (5, 10, and 20 mg/kg/day) or resveratrol (10 mg/kg/day). It was found that the body weight, Lee's index, ratio of visceral adipose tissue (VAT) to body weight, and blood glucose were significantly reduced in BTM-0512-treated mice when compared with those in mice treated with resveratrol. BTM-0512 up-regulated the expressions of SIRT1, full length PRDM16 (fPRDM16), total PRDM16 (tPRDM16, including fPPRDM16 and other PRDM16 isoforms), and uncoupling protein 1 (UCP1) in both brown and subcutaneous adipose tissues. Although BTM-0512 and resveratrol also up-regulated SIRT1 and tPRDM16 levels in VAT of HFD-induced obese mice, the expressions of fPRDM16, UCP1, and TMEM26 were down-regulated. In mouse primary subcutaneous preadipocytes cultured with or without adipogenic medium, BTM-0512 up-regulated fPRDM16, tPRDM16, and UCP1 expressions, which was reversed by SIRT1 antagonists. But in cultured brown and visceral adipocytes, the UCP1 protein level showed no significant change after treatment with 1 µM of BTM-0512. Moreover, transfection with human SIRT1 plasmid reduced lipid deposit, as well as the mRNA levels of fPRDM16, UCP1, and TMEM26, in cultured human visceral adipose-derived stem cells. In conclusion, BTM-0512 has stronger anti-obesity effect than resveratrol, which might be associated with activation of beige remodeling in subcutaneous adipose tissue.


Subject(s)
Adipocytes/drug effects , Adipose Tissue, Beige/drug effects , Obesity/prevention & control , Stilbenes/pharmacology , Subcutaneous Fat/drug effects , Adipocytes/metabolism , Adipose Tissue, Beige/cytology , Adipose Tissue, Beige/metabolism , Adipose Tissue, Brown/cytology , Adipose Tissue, Brown/drug effects , Adipose Tissue, Brown/metabolism , Animals , Blotting, Western , Body Weight/drug effects , Cells, Cultured , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Diet, High-Fat/adverse effects , Gene Expression/drug effects , Humans , Male , Mice, Inbred C57BL , Molecular Structure , Obesity/etiology , Obesity/metabolism , Resveratrol , Reverse Transcriptase Polymerase Chain Reaction , Sirtuin 1/genetics , Sirtuin 1/metabolism , Stilbenes/chemistry , Subcutaneous Fat/cytology , Subcutaneous Fat/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Uncoupling Protein 1/genetics , Uncoupling Protein 1/metabolism
15.
Biochimie ; 111: 119-24, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25701551

ABSTRACT

Isogarcinol, a bioactive polyisoprenylated benzophenone derivative isolated from Garcinia mangostana L., has been shown previously to exert a strong inhibitory effect on calcineurin and is thus a potential oral, low-toxicity immunomodulatory drug. In the present study, enzyme kinetic analysis showed that inhibition of calcineurin by isogarcinol was competitive. Fluorescence spectroscopy indicated that isogarcinol bound to calcineurin. Isothermal titration calorimetry showed that binding was mainly driven by enthalpy, and was exothermic because the enthalpy change exceeded the entropy reduction. The interaction force is either hydrogen bonding or Van der Waals forces. Fluorescence resonance energy transfer and molecular docking experiments indicated that there were two potential binding sites for isogarcinol in the catalytic domain of calcineurin. In summary, isogarcinol binds directly to calcineurin in vitro, unlike the classical calcineurin inhibitors cyclosporin A and tacrolimus.


Subject(s)
Calcineurin/chemistry , Cyclosporine/chemistry , Garcinia/chemistry , Immunosuppressive Agents/chemistry , Immunosuppressive Agents/isolation & purification , Tacrolimus/chemistry , Benzophenones/chemistry , Humans , Protein Binding
16.
Int J Biol Macromol ; 72: 254-60, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25193101

ABSTRACT

Calcineurin (CN) is the target of the immunophilin-immunosuppressant complex, cyclophilin/cyclosporin A (CyP/CsA). RCAN1 has recently been shown to be an endogenous regulator of CN activity. We determined the enzymatic and thermodynamic aspects of CN inhibition by RCAN1. The IC50 values of isoforms RCAN1-1L and RCAN1-4 for CN were 2.7 µM and 2.6 µM, respectively. Two deletions in the CN catalytic subunit, one a deletion of Val314 in the Loop7 domain (ΔV314) and the other in the autoinhibitory domain (CNAabc), increased the sensitivity of CN to inhibition by RCAN1-1L. The IC50s of RCAN1-1L and RCAN1-4 for CN in homogenates of mouse brain were 141 nM and 100 nM, respectively. Using isothermal titration calorimetry (ITC), we found that the RCAN1-1L/CN or CyP/CsA/CN interactions were exothermic with a dissociation constant of 0.46 µM or 0.17 µM, respectively. Our ITC results show that the interactions between CN and its two inhibitors were both characterized by a favorable binding enthalpy change. We also confirmed that overexpression of RCAN1-1L could inhibit the transcriptional activation of an NFAT-dependent promoter in response to PMA and ionomycin by inhibiting CN activity in HEK293T cells. Our data should contribute to our understanding of the regulation of CN activity by endogenous inhibitors.


Subject(s)
Calcineurin Inhibitors/metabolism , Calcineurin/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Muscle Proteins/metabolism , Animals , Binding Sites , Calcineurin/chemistry , Calcineurin Inhibitors/chemistry , Calcium-Binding Proteins , Calorimetry , Cyclosporine/metabolism , HEK293 Cells , Humans , Intracellular Signaling Peptides and Proteins/chemistry , Mice , Muscle Proteins/chemistry , Thermodynamics
17.
IUBMB Life ; 65(5): 445-53, 2013 May.
Article in English | MEDLINE | ID: mdl-23436429

ABSTRACT

Calcineurin (CN) is an important phosphatase that mediates many physiological and pathological processes. The regulators of calcineurin (RCAN1) and Cu, Zn superoxide dismutase (SOD1) are two endogenous modulators of CN activity. Cyclosporine A (CsA) is a well-known exogenous inhibitor of CN and used as an immunosuppressive drug after transplantation and for the treatment of immune diseases. The degree of CN inhibition by CsA varies among each tissue. The brain accumulates low levels of CsA due to the blood-brain barrier after oral administration. In our study, we investigated RCAN1 and SOD1 expression in long-term CsA-treated mouse brain. Using Western blot, we found that chronic CsA treatment had caused significant up-regulation of RCAN1-1L and RCAN1-4 protein isoforms after 25 days in mouse brain. At the same time, chronic CsA treatment also resulted in decreased expression of SOD1. We simultaneously found more dramatic CN inhibition in mouse brain. It was suspected that the significant reduction of CN activity in vivo resulted partially from up-regulated RCAN1 and down-regulated SOD1 expression. In contrast, CsA treatment in SY5Y cells affected SOD1 expression and CN activity significantly, but had no obvious effects on RCAN1-1 mRNA expression. The changes of RCAN1, SOD1, and CN activity may be part of maladaptive responses, resulting in neuropathological conditions. These data might partially explain CsA neurotoxicity despite the low concentration of CsA in brain.


Subject(s)
Brain/drug effects , Calcineurin/metabolism , Cyclosporine/pharmacology , Gene Expression Regulation/drug effects , Administration, Oral , Animals , Calcineurin/genetics , Calcium-Binding Proteins , Cell Line, Tumor , Humans , Immunosuppressive Agents/pharmacology , Intracellular Signaling Peptides and Proteins/genetics , Mice , Muscle Proteins/genetics , Superoxide Dismutase/genetics , Superoxide Dismutase-1 , Up-Regulation/drug effects
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