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1.
Langmuir ; 38(38): 11675-11682, 2022 09 27.
Article in English | MEDLINE | ID: mdl-36098991

ABSTRACT

High internal phase emulsions (HIPEs) provide a versatile platform for encapsulating large volumes of therapeutics that are immiscible in water. A stable scaffold is obtained by polymerizing the external phase, resulting in polyHIPEs. However, fabrication of polyHIPEs usually requires using a considerable quantity of surfactants along with nonbiocompatible components, which hinders their biological applications, e.g., drug-eluting devices. We describe here a straightforward method for generating porous biomaterials by using proteins as both the emulsifier and the building blocks for the fabrication of polyHIPEs. We demonstrate the versatility of this method by using different essential oils as the internal phase. After the gelation of protein building blocks is triggered by the addition of reducing agents, a stable protein hydrogel containing essential oils can be formed. These oils can be either extracted to obtain protein-based porous scaffolds or slowly released for antimicrobial applications.


Subject(s)
Anti-Infective Agents , Oils, Volatile , Anti-Infective Agents/pharmacology , Biocompatible Materials , Emulsions , Hydrogels , Oils, Volatile/pharmacology , Porosity , Reducing Agents , Surface-Active Agents , Water
2.
J Am Chem Soc ; 143(12): 4758-4765, 2021 03 31.
Article in English | MEDLINE | ID: mdl-33705125

ABSTRACT

Intracellular protein delivery enables selective regulation of cellular metabolism, signaling, and development through introduction of defined protein quantities into the cell. Most applications require that the delivered protein has access to the cytosol, either for protein activity or as a gateway to other organelles such as the nucleus. The vast majority of delivery vehicles employ an endosomal pathway however, and efficient release of entrapped protein cargo from the endosome remains a challenge. Recent research has made significant advances toward efficient cytosolic delivery of proteins using polymers, but the influence of polymer architecture on protein delivery is yet to be investigated. Here, we developed a family of dendronized polymers that enable systematic alterations of charge density and structure. We demonstrate that while modulation of surface functionality has a significant effect on overall delivery efficiency, the endosomal release rate can be highly regulated by manipulating polymer architecture. Notably, we show that large, multivalent structures cause slower sustained release, while rigid spherical structures result in rapid burst release.


Subject(s)
Cytosol/metabolism , Polymers/chemistry , Protein Engineering , Proteins/metabolism , Animals , Cell Line , Cytosol/chemistry , Humans , Mice , Molecular Structure , Polymers/metabolism , Proteins/chemistry
3.
Bioconjug Chem ; 32(5): 891-896, 2021 05 19.
Article in English | MEDLINE | ID: mdl-33872490

ABSTRACT

Intracellular protein delivery is a transformative tool for biologics research and medicine. Delivery into the cytosol allows proteins to diffuse throughout the cell and access subcellular organelles. Inefficient delivery caused by endosomal entrapment is often misidentified as cytosolic delivery. This inaccuracy muddles what should be a key checkpoint in assessing delivery efficiency. Green fluorescent protein (GFP) is a robust cargo small enough to passively diffuse from the cytosol into the nucleus. Fluorescence of GFP in the nucleus is a direct readout for cytosolic access and effective delivery. Here, we highlight recent examples from the literature for the accurate assessment of cytosolic protein delivery using GFP fluorescence in the cytosol and nucleus.


Subject(s)
Bacterial Proteins/metabolism , Cell Nucleus/metabolism , Cytosol/metabolism , Luminescent Proteins/metabolism , Active Transport, Cell Nucleus , Animals , Humans
4.
BMC Gastroenterol ; 21(1): 272, 2021 Jul 02.
Article in English | MEDLINE | ID: mdl-34215188

ABSTRACT

BACKGROUND: Lower gastrointestinal bleeding (LGIB) is very common in the hospital setting. Most bleedings stop spontaneously, but rare infectious causes of LGIB may lead to rapid and serious complications if left untreated and are sometimes very difficult to diagnose preoperatively. CASE PRESENTATION: We described a young man with poorly controlled Type I diabetes mellitus and chronic alcohol abuse who presented with acute altered mental status. During his hospitalization for treatment of diabetic ketoacidosis, acute renal failure, and sepsis, he suddenly developed massive hematochezia of 1500 mL. Colonoscopy was performed and a deep ulcer covered with mucus with peripheral elevation was noted at the transverse colon. Biopsy of the ulcer later revealed nonpigmented, wide (5-20 µm in diameter), thin-walled, ribbon-like hyphae with few septations and right-angle branching suggestive of mucormycosis demonstrated by Periodic acid-Schiff stain. He received 2 months of antifungal treatment. Follow up colonoscopy post-treatment was normal with no ulcer visualized. CONCLUSIONS: Early diagnosis and treatment of gastrointestinal (GI) mucormycosis infection is critical but can be challenging, especially in the setting of massive hematochezia. Therefore, clinical awareness for immunocompromised patients and prompt antifungal prophylaxis in cases with high suspicion of infection are essential.


Subject(s)
Mucormycosis , Antifungal Agents/therapeutic use , Colonoscopy , Gastrointestinal Hemorrhage/drug therapy , Humans , Immunocompromised Host , Male , Mucormycosis/drug therapy
5.
J Am Chem Soc ; 142(9): 4349-4355, 2020 03 04.
Article in English | MEDLINE | ID: mdl-32049533

ABSTRACT

Nanocarrier-mediated protein delivery is a promising strategy for fundamental research and therapeutic applications. However, the efficacy of the current platforms for delivery into cells is limited by endosomal entrapment of delivered protein cargo with concomitantly inefficient access to the cytosol and other organelles, including the nucleus. We report here a robust, versatile polymeric-protein nanocomposite (PPNC) platform capable of efficient (≥90%) delivery of proteins to the cytosol. We synthesized a library of guanidinium-functionalized poly(oxanorborneneimide) (PONI) homopolymers with varying molecular weights to stabilize and deliver engineered proteins featuring terminal oligoglutamate "E-tags". The polymers were screened for cytosolic delivery efficiency using imaging flow cytometry with cytosolic delivery validated using confocal microscopy and activity of the delivered proteins demonstrated through functional assays. These studies indicate that the PPNC platform provides highly effective and tunable cytosolic delivery over a wide range of formulations, making them robust agents for therapeutic protein delivery.


Subject(s)
Drug Carriers/metabolism , Integrases/metabolism , Luminescent Proteins/metabolism , Polyglutamic Acid/metabolism , Polymers/metabolism , Drug Carriers/chemical synthesis , Guanidines/chemical synthesis , Guanidines/metabolism , HEK293 Cells , HeLa Cells , Humans , Imides/chemical synthesis , Imides/metabolism , Nanocomposites/chemistry , Polymers/chemical synthesis , Protein Engineering , Red Fluorescent Protein
7.
Analyst ; 144(10): 3323-3333, 2019 May 13.
Article in English | MEDLINE | ID: mdl-30968864

ABSTRACT

Gas cluster ion beam (GCIB) is a promising technique for preserving molecular structures during ion sputtering and successfully profiling biological and soft materials. However, although GCIB yields lower damage accumulation compared with C60+ and monoatomic ion beams, the inevitable alteration of the chemical structure can introduce artifacts into the resulting depth profile. To enhance the ionization yield and further mask damage, a low-energy O2+ (200-500 V) cosputter can be applied. While the energy per atom (E/n) of GCIB is known to be an important factor influencing the sputter process, the manner through which E/n affects the GCIB-O2+ cosputter process remains unclear. In this study, poly(ethylene terephthalate) (PET) was used as a model material to investigate the sputter process of 10-20 kV Ar1000-4000+ (E/n = 2.5-20 eV per atom) with and without O2+ cosputter at different energies and currents. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) with Bi32+ as the primary ion was used to examine surfaces sputtered at different fluences. The sputter craters were also measured by alpha-step and atomic force microscopy in quantitative imaging mode. The SIMS results showed that the steady-state cannot be obtained with E/n values of less than 5 eV per atom due to damage accumulation using single GCIB sputtering. With a moderate E/n value of 5-15 eV per atom, the steady-state can be obtained, but the ∼50% decay in intensity indicated that damage cannot be masked completely despite the higher sputter yield. Furthermore, the surface Young's modulus decreased with increasing E/n, suggesting that depolymerization occurred. At an E/n value of 20 eV per atom, a failed profile was obtained with rapidly decreased sputter rate and secondary ion intensity due to the ion-induced crosslink. With O2+ cosputtering and a moderate E/n value, the oxidized species generated by O2+ enhanced the ionization yield, which led to a higher ion intensity at steady-state in general. Because higher kinetic energy or current density of O2+ led to a larger interaction volume and more structural damage that suppressed molecular ion intensity, the enhancement from O2+ was most apparent with low-energy-high-current (200 V, 80 µA cm-2) or high-energy-low-current (500 V, 5 µA cm-2) O2+ cosputtering with 0.5 µA cm-2 GCIBs. In these cases, little or no intensity drop was observed at the steady-state.

8.
Pacing Clin Electrophysiol ; 42(7): 882-889, 2019 07.
Article in English | MEDLINE | ID: mdl-31049997

ABSTRACT

AIMS: Catheter ablation has become an effective treatment modality for atrial fibrillation (AF). However, the relationship between common pulmonary vein (PV) and recurrent atrial tachyarrhythmia (ATA) after PV isolation (PVI) remains controversial. This study aimed to explore the function of common PV on the risk of recurrent ATA after PVI. METHODS: We identified a total of 191 patients who received radiofrequency catheter ablation for paroxysmal AF at our hospital between July 2010 and December 2017 for retrospective chart review. We collected the following data for analysis: results of preprocedural computed tomography, including the anatomy of PV and left atrial (LA) volume; the incidence of early- and late-onset recurrence of ATA. We compared these characteristics between the two groups defined by the presence or absence of the late-onset recurrence of ATA. RESULTS: Compared to the no ATA recurrence group, the ATA recurrence group had larger LA size, larger LA end-diastolic and systolic volumes, larger maximal diameter of PV, higher prevalence of common PV, and higher incidence of early-onset recurrence of ATA. In multivariate logistic regression analyses, presence of common PV and early-onset recurrence were independently associated with late-onset recurrence of ATA. Compared to patients without common PV, patients with common PV had larger diameter of PV and higher incidence of late-onset recurrent ATA. CONCLUSION: In patients with paroxysmal AF, early-onset recurrence of ATA and the presence of common PV were independently associated with late-onset recurrent ATA after radiofrequency catheter ablation.


Subject(s)
Atrial Fibrillation/surgery , Catheter Ablation/methods , Pulmonary Veins/surgery , Atrial Fibrillation/diagnostic imaging , Atrial Fibrillation/physiopathology , Echocardiography , Female , Humans , Male , Middle Aged , Recurrence , Tomography, X-Ray Computed
9.
Chem Soc Rev ; 47(10): 3421-3432, 2018 May 21.
Article in English | MEDLINE | ID: mdl-29537040

ABSTRACT

The delivery of proteins into cells is a potential game changer for a wide array of therapeutic purposes, including cancer therapy, immunomodulation and treatment of inherited diseases. In this review, we present recently developed nanoassemblies for protein delivery that utilize strategies that range from direct assembly, encapsulation and composite formation. We will discuss factors that affect the efficacy of nanoassemblies for delivery from the perspective of both nanoparticles and proteins. Challenges in the field, particularly achieving effective cytosolar protein delivery through endosomal escape or evasion are discussed.


Subject(s)
Nanoparticles/metabolism , Proteins/metabolism , Cell Line , Humans , Macromolecular Substances/chemical synthesis , Macromolecular Substances/chemistry , Macromolecular Substances/metabolism , Nanoparticles/chemistry , Proteins/chemistry
10.
J Am Chem Soc ; 140(38): 12137-12143, 2018 09 26.
Article in English | MEDLINE | ID: mdl-30169023

ABSTRACT

The rapid emergence of antibiotic-resistant bacterial "superbugs" with concomitant treatment failure and high mortality rates presents a severe threat to global health. The superbug risk is further exacerbated by chronic infections generated from antibiotic-resistant biofilms that render them refractory to available treatments. We hypothesized that efficient antimicrobial agents could be generated through careful engineering of hydrophobic and cationic domains in a synthetic semirigid polymer scaffold, mirroring and amplifying attributes of antimicrobial peptides. We report the creation of polymeric nanoparticles with highly efficient antimicrobial properties. These nanoparticles eradicate biofilms with low toxicity to mammalian cells and feature unprecedented therapeutic indices against red blood cells. Most notably, bacterial resistance toward these nanoparticles was not observed after 20 serial passages, in stark contrast to clinically relevant antibiotics where significant resistance occurred after only a few passages.


Subject(s)
Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Nanoparticles/chemistry , Polymers/pharmacology , Quaternary Ammonium Compounds/pharmacology , Animals , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/toxicity , Enterobacter cloacae/drug effects , Erythrocytes/drug effects , Escherichia coli/drug effects , Humans , Methicillin-Resistant Staphylococcus aureus/drug effects , Mice , Microbial Sensitivity Tests , NIH 3T3 Cells , Nanoparticles/toxicity , Polymers/chemical synthesis , Polymers/chemistry , Polymers/toxicity , Pseudomonas aeruginosa/drug effects , Quaternary Ammonium Compounds/chemical synthesis , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/toxicity
11.
J Am Chem Soc ; 140(19): 6176-6182, 2018 05 16.
Article in English | MEDLINE | ID: mdl-29709168

ABSTRACT

Infections caused by multidrug-resistant (MDR) bacteria are a rapidly growing threat to human health, in many cases exacerbated by their presence in biofilms. We report here a biocompatible oil-in-water cross-linked polymeric nanocomposite that degrades in the presence of physiologically relevant biomolecules. These degradable nanocomposites demonstrated broad-spectrum penetration and elimination of MDR bacteria, eliminating biofilms with no toxicity to cocultured mammalian fibroblast cells. Notably, serial passaging revealed that bacteria were unable to develop resistance toward these nanocomposites, highlighting the therapeutic promise of this platform.


Subject(s)
Anti-Bacterial Agents/pharmacology , Biocompatible Materials/pharmacology , Biofilms/drug effects , Drug Resistance, Multiple, Bacterial/drug effects , Escherichia coli/drug effects , Nanocomposites/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/metabolism , Biocompatible Materials/chemistry , Biocompatible Materials/metabolism , Cross-Linking Reagents/chemistry , Cross-Linking Reagents/metabolism , Cross-Linking Reagents/pharmacology , Microbial Sensitivity Tests , Molecular Structure
12.
Bioconjug Chem ; 29(2): 445-450, 2018 02 21.
Article in English | MEDLINE | ID: mdl-29298051

ABSTRACT

We present here an integrated nanotechnology/biology strategy for cancer immunotherapy that uses arginine nanoparticles (ArgNPs) to deliver CRISPR-Cas9 gene editing machinery into cells to generate SIRP-α knockout macrophages. The NP system efficiently codelivers single guide RNA (sgRNA) and Cas9 protein required for editing to knock out the "don't eat me signal" in macrophages that prevents phagocytosis of cancer cells. Turning off this signal increased the innate phagocytic capabilities of the macrophages by 4-fold. This improved attack and elimination of cancer cells makes this strategy promising for the creation of "weaponized" macrophages for cancer immunotherapy.


Subject(s)
CRISPR-Cas Systems , Gene Editing/methods , Macrophages/metabolism , Receptors, Immunologic/genetics , Animals , Clustered Regularly Interspaced Short Palindromic Repeats , Gene Knockout Techniques/methods , Humans , Immunotherapy/methods , Macrophages/immunology , Mice , Nanomedicine/methods , Neoplasms/immunology , Neoplasms/therapy , Phagocytosis , RAW 264.7 Cells , Receptors, Immunologic/immunology
13.
Proteomics ; 17(11)2017 Jun.
Article in English | MEDLINE | ID: mdl-28493537

ABSTRACT

We reported an integrated platform to explore serum protein variant pattern in cancer and its utility as a new class of biomarker panel for diagnosis. On the model study of serum amyloid A (SAA), we employed nanoprobe-based affinity mass spectrometry for enrichment, identification and quantitation of SAA variants from serum of 105 gastric cancer patients in comparison with 54 gastritis patients, 54 controls, and 120 patients from other cancer. The result revealed surprisingly heterogeneous and most comprehensive SAA bar code to date, which comprises 24 SAA variants including SAA1- and SAA2-encoded products, polymorphic isoforms, N-terminal-truncated forms, and three novel SAA oxidized isotypes, in which the variant-specific peptide sequence were also confirmed by LC-MS/MS. A diagnostic model was developed for dimension reduction and computational classification of the 24 SAA-variant bar code, providing good discrimination (AUC = 0.85 ± 3.2E-3) for differentiating gastric cancer group from gastritis and normal groups (sensitivity, 0.76; specificity, 0.81) and was validated with external validation cohort (sensitivity, 0.71; specificity, 0.74). Our platform not only shed light on the occurrence and modification extent of under-represented serum protein variants in cancer, but also suggested a new concept of diagnostic platform by serum protein variant profile.


Subject(s)
Gastric Mucosa/metabolism , Gastritis/diagnosis , Serum Amyloid A Protein/metabolism , Stomach Neoplasms/diagnosis , Chromatography, Liquid , Diagnosis, Differential , Gastritis/metabolism , Humans , Protein Isoforms , Stomach Neoplasms/metabolism , Tandem Mass Spectrometry
14.
Bioconjug Chem ; 28(4): 880-884, 2017 Apr 19.
Article in English | MEDLINE | ID: mdl-28263568

ABSTRACT

The successful use of clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9-based gene editing for therapeutics requires efficient in vivo delivery of the CRISPR components. There are, however, major challenges on the delivery front. In this Topical Review, we will highlight recent developments in CRISPR delivery, and we will present hurdles that still need to be overcome to achieve effective in vivo editing.


Subject(s)
CRISPR-Cas Systems , Clustered Regularly Interspaced Short Palindromic Repeats , Gene Editing/methods , Animals , Gene Transfer Techniques , Genetic Therapy/methods , Genetic Vectors/administration & dosage , Genetic Vectors/genetics , Humans , Mutagenesis, Insertional/methods , Viruses/genetics
16.
Heliyon ; 10(6): e28333, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38524572

ABSTRACT

Brown tumors (osteitis fibrosa cystica) are rare pathognomonic signs that occur in patients with primary hyperparathyroidism (PHPT). Brown tumors can exist in multiple bones and can easily be misdiagnosed as a metastatic tumor or multiple myeloma. It is also localized in the forearm, humerus, and leg. The symptoms of hypercalcemia, pathologic fracture, and bodyweight loss may increase the diagnostic difficulty of brown tumors because multiple myeloma and bone metastasis also show the same symptoms. We studied a 68-year-old woman who had experienced unusual bodyweight loss in the past 6 months (56kg-40kg) and bone pain. She went to the hospital after a fall with a complaint of bone pain. An X-ray revealed a left bubbly-like cystic change and multiple fractures at the left ulna midshaft. Upon investigation, the level of intact parathyroid hormone was ascertained to be 1800 (normal: 10-60) pg/ml. Microscopically, the tumor demonstrated a benign bone lesion and was compatible with osteitis fibrosa cystica due to PHPT. The parathyroid scan (Tc-99 m sestamibi) indicated right parathyroid hyperplasia, which was later confirmed by a parathyroidectomy. She was diagnosed with osteitis fibrosa cystica associated with PHPT due to a parathyroid adenoma. PHPT can be presented with multiple fractures, bone pain, and bodyweight loss. Therefore, if a patient presents these symptoms, PHPT should be considered.

17.
Pathology ; 56(5): 671-680, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38852040

ABSTRACT

Flow cytometry can be applied in the detection of fluorescence in situ hybridisation (FISH) signals to efficiently analyse chromosomal aberrations. However, such interphase chromosome (IC) Flow-FISH protocols are currently limited to detecting a single colour. Furthermore, combining IC Flow-FISH with conventional multicolour flow cytometry is difficult because the DNA-denaturation step in FISH assay also disrupts cellular integrity and protein structures, precluding subsequent antigen-antibody binding and hindering concurrent labeling of surface antigens and FISH signals. We developed a working protocol for concurrent multicolour flow cytometry detection of nuclear IC FISH signals and cell surface markers. The protocol was validated by assaying sex chromosome content of blood cells, which was indicative of chimerism status in patients who had received sex-mismatched allogeneic haematopoietic stem cell transplants (allo-HSCT). The method was also adapted to detect trisomy 12 in chronic lymphocytic leukaemia (CLL) subjects. We first demonstrated the feasibility of this protocol in detecting multiple colours and concurrent nuclear and surface signals with high agreement. In clinical validation experiments, chimerism status was identified in clinical samples (n=56) using the optimised IC Flow-FISH method; the results tightly corresponded to those of conventional slide-based FISH (R2=0.9649 for XX cells and 0.9786 for XY cells). In samples from patients who received sex-mismatched allo-HSCT, individual chimeric statuses in different lineages could be clearly distinguished with high flexibility in gating strategies. Furthermore, in CLL samples with trisomy 12, this method could demonstrate that enriched trisomy 12 FISH signal was present in B cells rather than in T cells. Finally, by performing combined labelling of chromosome 12, X chromosome, and surface markers, we could detect rare residual recipient CLL cells with trisomy 12 after allo-HSCT. This adaptable protocol for multicolour and lineage-specific IC Flow-FISH advances the technique to allow for its potential application in various clinical contexts where conventional FISH assays are currently being utilised.


Subject(s)
Flow Cytometry , In Situ Hybridization, Fluorescence , Interphase , Leukemia, Lymphocytic, Chronic, B-Cell , Humans , In Situ Hybridization, Fluorescence/methods , Flow Cytometry/methods , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Female , Male , Hematopoietic Stem Cell Transplantation , Trisomy/diagnosis , Trisomy/genetics , Middle Aged , Chromosomes, Human, Pair 12/genetics
18.
J Hazard Mater ; 466: 133590, 2024 03 15.
Article in English | MEDLINE | ID: mdl-38280324

ABSTRACT

Mox macrophages were identified recently and are closely associated with atherosclerosis. Considering the potential health risks and the impact on macrophage modulation, this study investigated the Mox polarization of macrophages induced by nanoparticles (NPs) with tunable hydrophobicity. One nanoparticle (C4NP) with intermediate hydrophobicity efficiently upregulated the mRNA expression of Mox-related genes including HO-1, Srxn1, Txnrd1, Gsr, Vegf and Cox-2 through increased accumulation of Nrf2 at a nontoxic concentration in both resting and LPS-challenged macrophages. Additionally, C4NP impaired phagocytic capacity by 20% and significantly increased the secretion of cytokines, including TNFα, IL-6 and IL-10. Mechanistic studies indicated that intracellular reactive oxygen species (ROS) were elevated by 1.5-fold and 2.6-fold in resting and LPS-challenged macrophages respectively. Phosphorylated p62 was increased by 2.5-fold in resting macrophages and maintained a high level in LPS-challenged ones, both of which partially accounted for the significant accumulation of Nrf2 and HO-1. Notably, C4NP depolarized mitochondrial membrane potential by more than 50% and switched macrophages from oxidative phosphorylation-based aerobic metabolism to glycolysis for energy supply. Overall, this study reveals a novel molecular mechanism potentially involving ROS-Nrf2-p62 signaling in mediating macrophage Mox polarization, holding promise in ensuring safer and more efficient use of nanomaterials.


Subject(s)
NF-E2-Related Factor 2 , Nanoparticles , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Reactive Oxygen Species/metabolism , Lipopolysaccharides/pharmacology , Macrophages/metabolism , Nanoparticles/toxicity , Heme Oxygenase-1/genetics
19.
BMC Genomics ; 14: 824, 2013 Nov 23.
Article in English | MEDLINE | ID: mdl-24267727

ABSTRACT

BACKGROUND: SUMOylation, as part of the epigenetic regulation of transcription, has been intensively studied in lower eukaryotes that contain only a single SUMO protein; however, the functions of SUMOylation during mammalian epigenetic transcriptional regulation are largely uncharacterized. Mammals express three major SUMO paralogues: SUMO-1, SUMO-2, and SUMO-3 (normally referred to as SUMO-1 and SUMO-2/3). Herpesviruses, including Kaposi's sarcoma associated herpesvirus (KSHV), seem to have evolved mechanisms that directly or indirectly modulate the SUMO machinery in order to evade host immune surveillance, thus advancing their survival. Interestingly, KSHV encodes a SUMO E3 ligase, K-bZIP, with specificity toward SUMO-2/3 and is an excellent model for investigating the global functional differences between SUMO paralogues. RESULTS: We investigated the effect of experimental herpesvirus reactivation in a KSHV infected B lymphoma cell line on genomic SUMO-1 and SUMO-2/3 binding profiles together with the potential role of chromatin SUMOylation in transcription regulation. This was carried out via high-throughput sequencing analysis. Interestingly, chromatin immunoprecipitation sequencing (ChIP-seq) experiments showed that KSHV reactivation is accompanied by a significant increase in SUMO-2/3 modification around promoter regions, but SUMO-1 enrichment was absent. Expression profiling revealed that the SUMO-2/3 targeted genes are primarily highly transcribed genes that show no expression changes during viral reactivation. Gene ontology analysis further showed that these genes are involved in cellular immune responses and cytokine signaling. High-throughput annotation of SUMO occupancy of transcription factor binding sites (TFBS) pinpointed the presence of three master regulators of immune responses, IRF-1, IRF-2, and IRF-7, as potential SUMO-2/3 targeted transcriptional factors after KSHV reactivation. CONCLUSION: Our study is the first to identify differential genome-wide SUMO modifications between SUMO paralogues during herpesvirus reactivation. Our findings indicate that SUMO-2/3 modification near protein-coding gene promoters occurs in order to maintain host immune-related gene unaltered during viral reactivation.


Subject(s)
Chromatin/metabolism , Herpesvirus 8, Human/physiology , Small Ubiquitin-Related Modifier Proteins/metabolism , Sumoylation , Ubiquitins/metabolism , Virus Activation , Cell Line, Tumor , Chromatin/virology , Chromatin Immunoprecipitation , Epigenesis, Genetic/immunology , Gene Ontology , Genes, MHC Class II , HEK293 Cells , Humans , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/metabolism , Promoter Regions, Genetic , Protein Binding , Transcription Factors/metabolism , Transcriptome
20.
Diagnostics (Basel) ; 13(16)2023 Aug 11.
Article in English | MEDLINE | ID: mdl-37627914

ABSTRACT

Previous studies have shown that hyperthyroidism is associated with heightened insulin resistance and dyslipidemia. Therefore, in this study, we aim to explore the relationship between elevated thyroid hormone levels and the lipid profile in insulin resistance in patients with type 2 diabetes mellitus (T2DM) with hyperthyroidism. A total of 177 participants were included and grouped according to diagnosis. The serum test results demonstrated that free thyroxine (FT4) increased the insulin resistance index (HOMA-IR) by positively correlating with triglyceride (TG) levels (p = 0.005, r2 = 0.35). In patients with T2DM with hyperthyroidism, the decreasing high-density lipoprotein levels showed an association with HOMA-IR (p = 0.005). Among all the patients, with different levels of FT4, the areas under the ROC curve (AUCs) of the TG level, TG/high-density lipoprotein ratio, and HOMA-IR were 0.620 (95% CI: 0.536 to 0.698), 0.614 (95% CI: 0.530 to 0.692), and 0.722 (95% CI: 0.645 to 0.791), respectively. Our results suggest that elevated FT4 levels due to hyperthyroidism could alter the association with the lipid profile and insulin resistance in patients with T2DM. We also suggest that among all the included patients with T2DM, irrespective of the presence of hyperthyroidism, FT4 levels are positively correlated with insulin resistance.

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