RESUMEN
Lipid droplets are not only lipid storage sites but also are closely related to lipid metabolism. Lipid droplet growth increases lipid storage capacity and suppresses lipolysis via lipase associated with the lipid droplet surface. The cell death-inducing DFF45-like effector (CIDE) family of proteins mediates lipid droplet fusion, which mainly contributes to lipid droplet growth. We previously demonstrated small ubiquitin-like modifier (SUMO)-specific protease 2 (SENP2) plays important roles in lipid metabolism and induction/maintenance of adipogenesis. In this study, we determined whether SENP2 regulates lipid droplet size in adipocytes. Overexpression of SENP2 increased lipid droplet size in differentiated 3T3-L1 adipocytes and facilitated CIDEA transcription. We found SENP2 increased CIDEA expression mainly through desumoylation of estrogen-related receptor α (ERRα), which acted in coordination with peroxisome proliferator-activated receptor γ-coactivator α. In addition, palmitate treatment increased SENP2 and CIDEA mRNA levels. Specific small interfering RNA-mediated knockdown of SENP2, as well as ERRα knockdown, eliminated palmitate-induced CIDEA expression. These results suggest SENP2 enhances CIDEA expression by modulating ERRα when SENP2 is upregulated, such as after palmitate treatment, to increase lipid droplet size in adipocytes.
RESUMEN
This meta-analysis was performed to investigate whether calcium supplements and dairy products change obesity indices including fat mass. Original articles published in English between July 2009 and August 2019 were identified. Ten and 14 randomised controlled trials (RCTs) with ≥ 12 weeks interventions of calcium supplements and dairy products among overweight or obese adults aged ≥18 were critically reviewed. Mean difference (MD) or standardised mean difference (SMD) with 95% confidence interval (CI) were obtained using a random effect meta-analysis. Dairy products significantly changed fat mass (SMD, 95% CI; -0.40 [-0.77, -0.02]) and BMI (MD, 95% CI: -0.46 kg/m2 [-0.67, -0.26]), and calcium supplements also showed changes in fat mass (SMD, 95% CI; -0.15[-0.28, -0.02]). However, in the analysis of RCTs with low risk of bias scores, the significant changes remained only in the dairy-products intervention. Our findings suggest that dairy products without distinction of fat percentage may help reduce fat mass and BMI, but calcium supplements may not.
Asunto(s)
Adiposidad , Peso Corporal , Calcio , Productos Lácteos , Suplementos Dietéticos , Obesidad , Adulto , Calcio/administración & dosificación , Humanos , Obesidad/terapia , Sobrepeso/terapia , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Three-dimensional (3D) cell printing processes have been used widely in various tissue engineering applications due to the efficient embedding of living cells in appropriately designed micro- or macro-structures. However, there are several issues to overcome, such as the limited choice of bioinks and tailor-made fabricating strategies. Here, we suggest a new, innovative cell-printing process, supplemented with a core-sheath nozzle and an aerosol cross-linking method, to obtain multilayered cell-laden mesh structure and a newly considered collagen-based cell-laden bioink. To obtain a mechanically and biologically enhanced cell-laden structure, we used collagen-bioink in the core region, and also used pure alginate in the sheath region to protect the cells in the collagen during the printing and cross-linking process and support the 3D cell-laden mesh structure. To achieve the most appropriate conditions for fabricating cell-embedded cylindrical core-sheath struts, various processing conditions, including weight fractions of the cross-linking agent and pneumatic pressure in the core region, were tested. The fabricated 3D MG63-laden mesh structure showed significantly higher cell viability (92 ± 3%) compared with that (83 ± 4%) of the control, obtained using a general alginate-based cell-printing process. To expand the feasibility to stem cell-embedded structures, we fabricated a cell-laden mesh structure consisting of core (cell-laden collagen)/sheath (pure alginate) using human adipose stem cells (hASCs). Using the selected processing conditions, we could achieve a stable 3D hASC-laden mesh structure. The fabricated cell-laden 3D core-sheath structure exhibited outstanding cell viability (91%) compared to that (83%) of an alginate-based hASC-laden mesh structure (control), and more efficient hepatogenic differentiations (albumin: â¼ 1.7-fold, TDO-2: â¼ 7.6-fold) were observed versus the control. The selection of collagen-bioink and the new printing strategy could lead to an efficient way to achieve 3D cell-laden mesh structures that mimic the anatomical architecture of a patient's defective region.
Asunto(s)
Tejido Adiposo/citología , Impresión Tridimensional/instrumentación , Células Madre/citología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Alginatos/química , Supervivencia Celular , Colágeno/química , Ácido Glucurónico/química , Ácidos Hexurónicos/química , HumanosRESUMEN
Ventricular fibrillation (VF) is usually sustained, and it typically results in death unless electrical defibrillation is successfully performed within minutes. Although VF has been reported to spontaneously occur in vivo in some animal models and a few cases of self-terminating VF have been documented in clinical practice, no such case has been previously reported involving out-of-hospital emergency medical service(EMS) personnel. We report a case of self-terminating VF due to ST segment elevation myocardial infarction that was documented by continuous electrocardiogram (ECG) strip monitoring. A 70-year-old woman was transported to the emergency department by EMS due to chest discomfort. The EMS personnel monitored her by ECG using an automated external defibrillator with a 3-limb lead. During transport, she developed VF, which persisted for 43 seconds. Chest compression and defibrillation were not applied. The VF self-terminated, after which the patient promptly awoke. Emergency coronary angiography was performed,and a total occlusion of the middle left circumflex coronary artery was treated by percutaneous coronary intervention. Since then, no symptomatic arrhythmia or ST-segment change was detected by continuous ECG monitoring. The patient was discharged home without any sequelae on the fourth hospital day.
Asunto(s)
Infarto del Miocardio/complicaciones , Fibrilación Ventricular/diagnóstico , Anciano , Electrocardiografía , Femenino , Humanos , Remisión Espontánea , Transporte de Pacientes , Fibrilación Ventricular/etiologíaRESUMEN
We aimed to identify a novel flavonoid from the in-house natural products to suppress matrix metalloproteases (MMPs), which is responsible for degradation of collagen and other extracellular matrix proteins. Total eight natural products were screened for identification of a novel MMP-9 suppressor using MMP-9 reporter system, where the prompt initial screening with multiple samples is readily examined. Among the extracts used in the present study, one extract (Citrus unshiu) was found active in this assay system. Furthermore, three representative flavonoids in this active extract of Citrus unshiu peel were tested in MMP-9 reporter system. Nobiletin (NB) of the tested flavonoids suppressed MMP-9 expression without cytotoxicity, which was validated by both real-time polymerase chain reaction (PCR) and zymography analyses. Sustained p38 mitogen activated protein kinase (MAPK) activity, closely associated with induction of MMP-9 under stress condition, was markedly reduced by NB treatment, which implies that modulation of p38MAPK by nobiletin is responsible for reduction of MMP9 expression. Hence, nobiletin, identified from MMP-9 reporter system based screening, may be further applied for the purpose of delaying collagen degradation in skin fibroblasts.
Asunto(s)
Citrus/química , Fibroblastos/efectos de los fármacos , Flavonas/farmacología , Metaloproteinasa 9 de la Matriz/metabolismo , Extractos Vegetales/farmacología , Piel/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Colágeno/efectos de los fármacos , Colágeno/metabolismo , Fibroblastos/metabolismo , Humanos , Fosforilación , Piel/citología , Piel/metabolismoRESUMEN
Background and Purpose: Ventricle enlargement has been implicated in the pathophysiology of Alzheimer's disease (AD). We studied the relationship between ventricular size and cognitive function in patients with AD. We focused on the effect of the initial ventricle size on the rate of cognitive decline in patients with AD. Methods: A retrospective analysis of probable clinical AD participants with more than 2 magnetic resonance imaging images was performed. To measure ventricle size, we used visual rating scales of (1) Cardiovascular Health Study (CHS) score and (2) conventional linear measurement method. Results: Increased clinical dementia rating (CDR) was correlated with a decreased Mini-Mental Status Examination (MMSE) score, and increased medial temporal lobe atrophy (MTLA) and global ventricle size (p<0.001, p<0.001, p=0.021, respectively). There was a significant correlation between the change in cognitive function in the group (70%-100%ile) with a large initial ventricle size (p=0.021 for ΔCDR, p=0.01 for ΔMMSE), while the median ventricle size (30%-70%ile) showed correlation with other brain structural changes (MTLA, frontal atrophy [FA], and white matter) (p=0.036 for initial MTLA, p=0.034 for FA). Conclusions: In this study, the initial ventricle size may be a potential new imaging biomarker for initial cognitive function and clinical progression in AD. We found a relationship between the initial ventricle size and initial AD-related brain structural biomarkers.
RESUMEN
BACKGROUND: The efficacy of cell implantation via 3D-spheroids to treat basal tone in fecal incontinence remains unclear. To address this, in this study, we aimed to identify cell differentiation and assess the development of a contractile phenotype corresponding to smooth muscle cells (SMCs) following implantation of 3D-spheroid and 2D-cultured human adipose stem cells (hASCs) in an in vivo internal anal sphincter (IAS)-targeted mouse model. METHODS: We developed an IAS-targeted in vivo model via rapid freezing (at - 196 °C) of the dorsal layers of the region of interest (ROI) of the IAS ring posterior quarter, between the submucosal and muscular layers, following submucosal dissection (n = 60 rats). After implantation of tetramethylindocarbocyanine perchlorate (Dil)-stained 3D and 2D-cells into randomly allocated cryoinjured rats, the entire sphincter ring or only the cryoinjured ROI was harvested. Expression of SMC markers, RhoA/ROCKII and its downstream molecules, and fibrosis markers was analyzed. Dil, α-smooth muscle actin (α-SMA), and RhoA signals were used for cell tracking. RESULTS: In vitro, 3D-spheroids exhibited higher levels of SMC markers and RhoA/ROCKII-downstream molecules than 2D-hASCs. The IAS-targeted cryoinjured model exhibited substantial loss of SMC layers of the squamous epithelium lining of the anal canal, as well as reduced expression of SMC markers and RhoA-related downstream molecules. In vivo, 3D-spheroid implantation induced SMC markers and contractile molecules weakly at 1 week. At 2 weeks, the mRNA expression of aSma, Sm22a, Smoothelin, RhoA, Mypt1, Mlc20, Cpi17, and Pp1cd increased, whereas that of fibrosis markers reduced significantly in the 3D-spheroid implanted group compared to those in the sham, non-implanted, and 2D-hASC implanted groups. Protein levels of RhoA, p-MYPT1, and p-MLC20 were higher in the 3D-spheroid-implanted group than in the other groups. At 2 weeks, in the implanted groups, the cryoinjured tissues (which exhibited Dil, α-SMA, and RhoA signals) were restored, while they remained defective in the sham and non-implanted groups. CONCLUSIONS: These findings demonstrate that, compared to 2D-cultured hASCs, 3D-spheroids more effectively induce a contractile phenotype that is initially weak but subsequently improves, inducing expression of RhoA/ROCKII-downstream molecules and SMC differentiation associated with IAS basal tone.
Asunto(s)
Canal Anal , Diferenciación Celular , Miocitos del Músculo Liso , Animales , Humanos , Ratones , Canal Anal/patología , Canal Anal/metabolismo , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/citología , Ratas , Modelos Animales de Enfermedad , Esferoides Celulares/metabolismo , Esferoides Celulares/citología , Células Madre/metabolismo , Células Madre/citología , Células Cultivadas , Ratas Sprague-Dawley , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , MasculinoRESUMEN
OBJECTIVES: The Xq28 region containing IRAK1 and MECP2 has been identified as a risk locus for systemic lupus erythematosus (SLE) in previous genetic association studies. However, due to the strong linkage disequilibrium between IRAK1 and MECP2, it remains unclear which gene is affected by the underlying causal variant(s) conferring risk of SLE. METHODS: We fine-mapped ≥136 SNPs in a â¼227 kb region on Xq28, containing IRAK1, MECP2 and seven adjacent genes (L1CAM, AVPR2, ARHGAP4, NAA10, RENBP, HCFC1 and TMEM187), for association with SLE in 15 783 case-control subjects derived from four different ancestral groups. RESULTS: Multiple SNPs showed strong association with SLE in European Americans, Asians and Hispanics at p<5×10(-8) with consistent association in subjects with African ancestry. Of these, six SNPs located in the TMEM187-IRAK1-MECP2 region captured the underlying causal variant(s) residing in a common risk haplotype shared by all four ancestral groups. Among them, rs1059702 best explained the Xq28 association signals in conditional testings and exhibited the strongest p value in transancestral meta-analysis (p(meta )= 1.3×10(-27), OR=1.43), and thus was considered to be the most likely causal variant. The risk allele of rs1059702 results in the amino acid substitution S196F in IRAK1 and had previously been shown to increase NF-κB activity in vitro. We also found that the homozygous risk genotype of rs1059702 was associated with lower mRNA levels of MECP2, but not IRAK1, in SLE patients (p=0.0012) and healthy controls (p=0.0064). CONCLUSIONS: These data suggest contributions of both IRAK1 and MECP2 to SLE susceptibility.
Asunto(s)
Cromosomas Humanos X/genética , Quinasas Asociadas a Receptores de Interleucina-1/genética , Lupus Eritematoso Sistémico/genética , Proteína 2 de Unión a Metil-CpG/genética , Grupos Raciales/genética , Secuencia de Bases , Mapeo Cromosómico , Predisposición Genética a la Enfermedad/genética , Genotipo , Haplotipos , Humanos , Datos de Secuencia Molecular , Polimorfismo de Nucleótido Simple , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de RiesgoRESUMEN
Keloids are characterised by the excessive accumulation of extracellular matrix (ECM), especially overabundant collagen formation. In keloid fibroblasts (KFs), transforming growth factor (TGF)-ß-dependent signalling is closely associated with a variety of keloid pathologic responses such as ECM production and fibroblast overgrowth. Thus, inhibition of TGF-ß signalling would be a potential therapeutic approach to prevent keloid scar formation. Thereby, we aimed to identify a novel TGF-ß signalling blocker among natural products using a simplified screening approach. We discovered that the extract of Aneilema keisak (A.K-Ex) lowered TGF-ß-dependent signalling by reducing Smad2 protein levels. Given that KFs showed altered dependency on TGF-ß for survival and proliferation, A.K-Ex-mediated reduction in Smad2 protein levels significantly inhibited the major characteristics of KFs such as cell growth, migration and collagen synthesis, suggesting that A.K-Ex exhibits possible therapeutic activity on keloids.
Asunto(s)
Commelinaceae , Fibroblastos/efectos de los fármacos , Extractos Vegetales/farmacología , Transducción de Señal/efectos de los fármacos , Proteína Smad2/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Colágeno/biosíntesis , Regulación hacia Abajo/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Queloide/tratamiento farmacológicoRESUMEN
Two new triterpenes, (1α,3ß,8α,9ß,10α,13α,14ß)-9,10-dimethyl-25,26-dinorolean-5-en-1,3-diol (1) and (1α,3ß,6ß)-olean-12-en-1,3,6-triol (2) were isolated from the leaves of Aleurites fordii, together with five known triterpenes. The structures of isolates were established by one dimensional (1D)- and 2D-NMR spectroscopic data along with MS analysis. Of the isolated compounds, 1, 2 and 4 (daturadiol) displayed moderate cytotoxicities against two or more human cancer cell lines in HepG2 (hepatocellular carcinoma), SK-OV-3 (ovarian carcinoma), A-549 (lung carcinoma) and SNU-1 (gastric carcinoma).
Asunto(s)
Euphorbiaceae/química , Triterpenos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Células Hep G2 , Humanos , Espectroscopía de Resonancia Magnética , Conformación Molecular , Hojas de la Planta/química , Triterpenos/aislamiento & purificación , Triterpenos/toxicidadRESUMEN
BACKGROUND: Leptin is a 16-kDa fat-derived hormone with a primary role in controlling adipose tissue levels. Leptin increases fatty acid oxidation (FAO) acutely through adenosine monophosphate-activated protein kinase (AMPK) and on delay through the SUMO-specific protease 2 (SENP2)-peroxisome proliferator-activated receptor δ/γ (PPARδ/γ) pathway in skeletal muscle. Leptin also directly increases FAO and decreases lipogenesis in adipocytes; however, the mechanism behind these effects remains unknown. Here, we investigated the role of SENP2 in the regulation of fatty acid metabolism by leptin in adipocytes and white adipose tissues. METHODS: The effects of leptin mediated by SENP2 on fatty acid metabolism were tested by siRNA-mediated knockdown in 3T3-L1 adipocytes. The role of SENP2 was confirmed in vivo using adipocyte-specific Senp2 knockout (Senp2-aKO) mice. We revealed the molecular mechanism involved in the leptin-induced transcriptional regulation of carnitine palmitoyl transferase 1b (Cpt1b) and long-chain acyl-coenzyme A synthetase 1 (Acsl1) using transfection/reporter assays and chromatin immunoprecipitation. RESULTS: SENP2 mediated the increased expression of FAO-associated enzymes, CPT1b and ACSL1, which peaked 24 hours after leptin treatment in adipocytes. In contrast, leptin stimulated FAO through AMPK during the initial several hours after treatment. In white adipose tissues, FAO and mRNA levels of Cpt1b and Acsl1 were increased by 2-fold 24 hours after leptin injection in control mice but not in Senp2-aKO mice. Leptin increased PPARα binding to the Cpt1b and Acsl1 promoters in adipocytes through SENP2. CONCLUSION: These results suggest that the SENP2-PPARα pathway plays an important role in leptin-induced FAO in white adipocytes.
Asunto(s)
Adipocitos Blancos , Leptina , Ratones , Animales , Leptina/farmacología , Adipocitos Blancos/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , PPAR alfa , Ácidos Grasos/genética , Ácidos Grasos/metabolismo , Péptido Hidrolasas , Cisteína Endopeptidasas/genéticaRESUMEN
OBJECTIVE: Studies on development of an anal incontinence (AI) model targeting smooth muscle cells (SMCs) of the internal anal sphincter (IAS) have not been reported. The differentiation of implanted human adipose-derived stem cells (hADScs) into SMCs in an IAS-targeting AI model has also not been demonstrated. We aimed to develop an IAS-targeting AI animal model and to determine the differentiation of hADScs into SMCs in an established model. MATERIALS AND METHODS: The IAS-targeting AI model was developed by inducing cryoinjury at the inner side of the muscular layer via posterior intersphincteric dissection in Sprague-Dawley rats. Dil-stained hADScs were implanted at the IAS injury site. Multiple markers for SMCs were used to confirm molecular changes before and after cell implantation. Analyses were performed using H&E, immunofluorescence, Masson's trichrome staining, and quantitative RT-PCR. RESULTS: Impaired smooth muscle layers accompanying other intact layers were identified in the cryoinjury group. Specific SMC markers, including SM22α, calponin, caldesmon, SMMHC, smoothelin, and SDF-1 were significantly decreased in the cryoinjured group compared with levels in the control group. However, CoL1A1 was increased significantly in the cryoinjured group. In the hADSc-treated group, higher levels of SMMHC, smoothelin, SM22α, and α-SMA were observed at two weeks after implantation than at one week after implantation. Cell tracking revealed that Dil-stained cells were located at the site of augmented SMCs. CONCLUSIONS: This study first demonstrated that implanted hADSc restored impaired SMCs at the injury site, showing stem cell fate corresponding to the established IAS-specific AI model.
RESUMEN
OBJECTIVE: T cells from patients with systemic lupus erythematosus (SLE) express increased amounts of PP2Ac, which contributes to decreased production of interleukin-2 (IL-2). Because IL-2 is important in the regulation of several aspects of the immune response, it has been proposed that PP2Ac contributes to the expression of SLE. This study was designed to determine whether genetic variants of PPP2AC are linked to the expression of SLE and specific clinical manifestations and account for the increased expression of PP2Ac. METHODS: We conducted a trans-ethnic study of 8,695 SLE cases and 7,308 controls of 4 different ancestries. Eighteen single-nucleotide polymorphisms (SNPs) across PPP2CA were genotyped using an Illumina custom array. PPP2CA expression in SLE and control T cells was analyzed by real-time polymerase chain reaction. RESULTS: A 32-kb haplotype comprising multiple SNPs of PPP2CA showed significant association with SLE in Hispanic Americans, European Americans, and Asians, but not in African Americans. Conditional analyses revealed that SNP rs7704116 in intron 1 showed consistently strong association with SLE across Asian, European American, and Hispanic American populations (odds ratio 1.3 [95% confidence interval 1.14-1.31], meta-analysis P=3.8×10(-7)). In European Americans, the largest ethnic data set studied, the risk A allele of rs7704116 was associated with the presence of renal disease, anti-double-stranded DNA, and anti-RNP antibodies. PPP2CA expression was â¼2-fold higher in SLE patients carrying the rs7704116 AG genotype than those carrying the GG genotype (P=0.007). CONCLUSION: Our data provide the first evidence of an association between PPP2CA polymorphisms and elevated PP2Ac transcript levels in T cells, which implicates a new molecular pathway for SLE susceptibility in European Americans, Hispanic Americans, and Asians.
Asunto(s)
Predisposición Genética a la Enfermedad , Lupus Eritematoso Sistémico/genética , Polimorfismo Genético , Proteína Fosfatasa 2/genética , Adolescente , Adulto , Alelos , Pueblo Asiatico , Femenino , Estudios de Asociación Genética , Genotipo , Haplotipos , Hispánicos o Latinos , Humanos , Interleucina-2/genética , Interleucina-2/metabolismo , Lupus Eritematoso Sistémico/inmunología , Masculino , Persona de Mediana Edad , Linfocitos T/metabolismo , Población BlancaRESUMEN
The complexity in the molecular mechanism of the internal anal sphincter (IAS) limits preclinical or clinical outcomes of fecal incontinence (FI) treatment. So far, there are no systematic reviews of IAS translation and experimental studies that have been reported. This systematic review aims to provide a comprehensive understanding of IAS critical role in FI. Previous studies revealed the key pathway for basal tone and relaxation of IAS in different properties as follows; calcium, Rho-associated, coiled-coil containing serine/threonine kinase, aging-associated IAS dysfunction, oxidative stress, renin-angiotensin-aldosterone, cyclooxygenase, and inhibitory neurotransmitters. Previous studies have reported improved functional outcomes of cellular treatment for regeneration of dysfunctional IAS, using various stem cells, but did not demonstrate the interrelationship between those results and basal tone or relaxation-related molecular pathway of IAS. Furthermore, these results have lower specificity for IAS-incontinence due to the included external anal sphincter or nerve injury regardless of the cell type. An acellular approach using bioengineered IAS showed a physiologic response of basal tone and relaxation response similar to human IAS. However, in both cellular and acellular approaches, the lack of human IAS data still hampers clinical application. Therefore, the IAS regeneration presents more challenges and warrants more advances.
RESUMEN
Increasing evidence has shown that small ubiquitin-like modifier (SUMO) modification plays an important role in metabolic regulation. We previously demonstrated that SUMO-specific protease 2 (SENP2) is involved in lipid metabolism in skeletal muscle and adipogenesis. In this study, we investigated the function of SENP2 in pancreatic ß cells by generating a ß cell-specific knockout (Senp2-ßKO) mouse model. Glucose tolerance and insulin secretion were significantly impaired in the Senp2-ßKO mice. In addition, glucose-stimulated insulin secretion (GSIS) was decreased in the islets of the Senp2-ßKO mice without a significant change in insulin synthesis. Furthermore, islets of the Senp2-ßKO mice exhibited enlarged mitochondria and lower oxygen consumption rates, accompanied by lower levels of S616 phosphorylated DRP1 (an active form of DRP1), a mitochondrial fission protein. Using a cell culture system of NIT-1, an islet ß cell line, we found that increased SUMO2/3 conjugation to DRP1 due to SENP2 deficiency suppresses the phosphorylation of DRP1, which possibly induces mitochondrial dysfunction. In addition, SENP2 overexpression restored GSIS impairment induced by DRP1 knockdown and increased DRP1 phosphorylation. Furthermore, palmitate treatment decreased phosphorylated DRP1 and GSIS in ß cells, which was rescued by SENP2 overexpression. These results suggest that SENP2 regulates mitochondrial function and insulin secretion at least in part by modulating the phosphorylation of DRP1 in pancreatic ß cells.
Asunto(s)
Células Secretoras de Insulina , Animales , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Glucosa/metabolismo , Insulina/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Ratones , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Péptido Hidrolasas/metabolismoRESUMEN
Coronavirus disease 2019 (COVID-19), the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is characterized by symptoms such as fever, fatigue, a sore throat, diarrhea, and coughing. Although various new vaccines against COVID-19 have been developed, early diagnostics, isolation, and prevention remain important due to virus mutations resulting in rapid and high disease transmission. Amino acid substitutions in the major diagnostic target antigens of SARS-CoV-2 may lower the sensitivity for the detection of SARS-CoV-2. For this reason, we developed specific monoclonal antibodies that bind to epitope peptides as antigens for the rapid detection of SARS-CoV-2 NP. The binding affinity between antigenic peptides and monoclonal antibodies was investigated, and a sandwich pair for capture and detection was employed to develop a rapid biosensor for SARS-CoV-2 NP. The rapid biosensor, based on a monoclonal antibody pair binding to conserved epitopes of SARS-CoV-2 NP, detected cultured virus samples of SARS-CoV-2 (1.4 × 103 TCID50/reaction) and recombinant NP (1 ng/mL). Laboratory confirmation of the rapid biosensor was performed with clinical specimens (n = 16) from COVID-19 patients and other pathogens. The rapid biosensor consisting of a monoclonal antibody pair (75E12 for capture and the 54G6/54G10 combination for detection) binding to conserved epitopes of SARS-CoV-2 NP could assist in the detection of SARS-CoV-2 NP under the circumstance of spreading SARS-CoV-2 variants.
Asunto(s)
Anticuerpos Monoclonales/metabolismo , Anticuerpos Antivirales/metabolismo , Técnicas Biosensibles/métodos , Epítopos/metabolismo , Proteínas de la Nucleocápside/metabolismo , SARS-CoV-2/inmunología , Proteínas Virales/metabolismo , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Epítopos/genética , Epítopos/inmunología , Humanos , Inmunoensayo , Ratones , Ratones Endogámicos BALB C , Proteínas de la Nucleocápside/genética , Proteínas de la Nucleocápside/inmunología , Péptidos/inmunología , Péptidos/metabolismo , Unión Proteica , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteínas Virales/inmunologíaRESUMEN
The adipose tissue is a key site regulating energy metabolism. One of the contributing factors behind this is browning of white adipose tissue (WAT). However, knowledge of the intracellular determinants of the browning process remains incomplete. By generating adipocyte-specific Senp2 knockout (Senp2-aKO) mice, here we show that SENP2 negatively regulates browning by de-conjugating small ubiquitin-like modifiers from C/EBPß. Senp2-aKO mice are resistant to diet-induced obesity due to increased energy expenditure and heat production. Senp2 knockout promotes beige adipocyte accumulation in inguinal WAT by upregulation of thermogenic gene expression. In addition, SENP2 knockdown promotes thermogenic adipocyte differentiation of precursor cells isolated from inguinal and epididymal WATs. Mechanistically, sumoylated C/EBPß, a target of SENP2, suppresses expression of HOXC10, a browning inhibitor, by recruiting a transcriptional repressor DAXX. These findings indicate that a SENP2-C/EBPß-HOXC10 axis operates for the control of beige adipogenesis in inguinal WAT.
Asunto(s)
Adipocitos Beige , Proteína beta Potenciadora de Unión a CCAAT , Cisteína Endopeptidasas , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina , Adipocitos Beige/metabolismo , Adipogénesis , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Animales , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Cisteína Endopeptidasas/metabolismo , Metabolismo Energético/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Termogénesis/genéticaRESUMEN
Thiazolidinediones (TZDs) are synthetic ligands of peroxisome proliferator-activated receptor-γ (PPARγ), a member of the nuclear receptor superfamily. TZDs are known to increase insulin sensitivity and also to have an antioxidative effect. In this study, we tested whether TZDs protect pancreatic ß-cells from oxidative stress, and we investigated the mechanism involved in this process. To generate oxidative stress in pancreatic ß-cells (INS-1 and ßTC3) or isolated islets, glucose oxidase was added to the media. The extracellular and intracellular reactive oxygen species (ROS) were measured to directly determine the antioxidant effect of TZDs. The phosphorylation of JNK/MAPK after oxidative stress was detected by Western blot analysis, and glucose-stimulated insulin secretion and cell viability were also measured. TZDs significantly reduced the ROS levels that were increased by glucose oxidase, and they effectively prevented ß-cell dysfunction. The antioxidative effect of TZDs was abolished in the presence of a PPARγ antagonist, GW9662. Real-time PCR was used to investigate the expression levels of antioxidant genes. The expression of catalase, an antioxidant enzyme, was increased by TZDs in pancreatic ß-cells, and the knockdown of catalase significantly inhibited the antioxidant effect of TZDs. These results suggest that TZDs effectively protect pancreatic ß-cells from oxidative stress, and this effect is dependent largely on PPARγ. In addition, the expression of catalase is increased by TZDs, and catalase, at least in part, mediates the antioxidant effect of TZDs in pancreatic ß-cells.
Asunto(s)
Antioxidantes/farmacología , Células Secretoras de Insulina/efectos de los fármacos , Tiazolidinedionas/farmacología , Animales , Células Cultivadas , Evaluación Preclínica de Medicamentos , Glucosa/farmacología , Peróxido de Hidrógeno/metabolismo , Hipoglucemiantes/farmacología , Insulina/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Ratones , PPAR gamma/agonistas , PPAR gamma/genética , PPAR gamma/metabolismo , Receptor alfa X Retinoide/agonistas , Receptor alfa X Retinoide/genética , Receptor alfa X Retinoide/metabolismo , Porcinos , TransfecciónRESUMEN
BACKGROUND: Epidemiological studies have shown that obesity/adiposity is closely associated with asthma in terms of development, severity, and control of asthma. However, effects of obesity/adiposity on airway inflammation are not well known in subjects without asthma. We assessed whether fractional exhaled nitric oxide (FeNO), a marker of eosinophilic airway inflammation, was associated with obesity/adiposity in nonasthmatic healthy adults. METHODS: We measured FeNO and serum levels of adipose-derived hormones and adipokines in 117 adult subjects without a previous diagnosis of asthma or current asthmatic symptoms. Associations between FeNO and measures of obesity/adiposity [body mass index (BMI), body fat mass, and body fat percentages] were examined by correlation analyses and uni- and multivariate linear regression analyses. RESULTS: FeNO was not significantly associated with BMI, body fat mass, or body fat percentage by a multivariate linear regression model, adjusting for age, gender, chronic rhinitis, atopy, and lung function. No significant association of FeNO with serum levels of leptin, adiponectin, tumor necrosis factor (TNF)-α, or interleukin (IL)-6 was observed. CONCLUSIONS: These findings suggest that in healthy subjects without asthma, obesity/adiposity has no significant effect on eosinophilic airway inflammation and that hormones and systemic inflammation derived from adipose tissue do not affect eosinophilic airway inflammation.
Asunto(s)
Óxido Nítrico/metabolismo , Obesidad/metabolismo , Adiponectina/sangre , Adulto , Anciano , Composición Corporal , Índice de Masa Corporal , Pruebas Respiratorias , Femenino , Humanos , Interleucina-6/sangre , Leptina/sangre , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/patología , Pruebas de Función Respiratoria , Estadísticas no Paramétricas , Factor de Necrosis Tumoral alfa/sangre , Adulto JovenRESUMEN
Currently, there are no approved therapeutics for Dengue virus (DENV) infection, even though it can cause fatal complications. Understanding DENV infection and its propagation process in host cells is necessary to develop specific antiviral therapeutics. Here, we developed a graphene oxide-based fluorescent system (Graphene Oxide-based Viral RNA Analysis system, GOViRA) that enables sensitive and quantitative real-time monitoring of the intracellular viral RNA level in living cells. The GOViRA system consists of a fluorescent dye-labeled peptide nucleic acid (PNA) with a complementary sequence to the DENV genome and a dextran-coated reduced graphene oxide nanocolloid (DRGON). When the dye labeled PNA is adsorbed onto DRGON, the fluorescence of the dye is effectively quenched. The quenched fluorescence signal is recovered when the dye labeled PNA forms interaction with intracellular viral RNA in DENV infected host cells. We demonstrated the successful use of the GOViRA platform for high-throughput screening to discover novel antiviral compounds. Through a cell-based high-throughput screening of FDA-approved small-molecule drugs, we identified ulipristal, a selective progesterone receptor modulator (SPRM), as a potent inhibitor against DENV infection. The anti-DENV activity of ulipristal was confirmed both in vitro and in vivo. Moreover, we suggest that the mode of action of ulipristal is mediated by inhibiting viral entry into the host cells.