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1.
Artículo en Inglés | MEDLINE | ID: mdl-38453603

RESUMEN

Cellular metabolism is a flexible and plastic network that often dictates physiological and pathological states of the cell, including differentiation, cancer, and aging. Recent advances in cancer metabolism represent a tremendous opportunity to treat cancer by targeting its altered metabolism. Interestingly, despite their stable growth arrest, senescent cells - a critical component of the aging process - undergo metabolic changes similar to cancer metabolism. A deeper understanding of the similarities and differences between these disparate pathological conditions will help identify which metabolic reprogramming is most relevant to the therapeutic liabilities of senescence. Here, we compare and contrast cancer and senescence metabolism and discuss how metabolic therapies can be established as a new modality of senotherapy for healthy aging.

2.
Gynecol Obstet Invest ; 88(5): 314-321, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37442099

RESUMEN

INTRODUCTION: Placental mesenchymal dysplasia (PMD) is a benign lesion that is often misdiagnosed as complete (CHM) or partial hydatidiform mole. PMD usually results in live birth but can be associated with several fetal defects. Herein, we report PMD with CHM in a singleton placenta with live birth. CASE PRESENTATION: A 34-year-old gravida 2, para 1, living 1 (G2P1L1) woman was referred on suspicion of a molar pregnancy in the first trimester. Maternal serum human chorionic gonadotrophin levels were increased during early pregnancy, with multicystic lesions and placentomegaly observed on ultrasonography. Levels decreased to normal with no fetal structural abnormalities observed. A healthy male infant was delivered at 34 gestational weeks. Placental p57KIP2 immunostaining and short tandem repeat analysis revealed three distinct histologies and genetic features: normal infant and placenta, PMD, and CHM. Gestational trophoblastic neoplasia was diagnosed and up to fourth-line chemotherapy administered. CONCLUSION: Distinguishing PMD from hydatidiform moles is critical for avoiding unnecessary termination of pregnancy. CHM coexisting with a live fetus rarely occurs. This case is unique in that a healthy male infant was born from a singleton placenta with PMD and CHM.


Asunto(s)
Enfermedad Trofoblástica Gestacional , Mola Hidatiforme , Enfermedades Placentarias , Neoplasias Uterinas , Masculino , Embarazo , Femenino , Humanos , Adulto , Placenta/diagnóstico por imagen , Placenta/patología , Nacimiento Vivo , Mola Hidatiforme/diagnóstico por imagen , Enfermedades Placentarias/diagnóstico por imagen , Enfermedad Trofoblástica Gestacional/diagnóstico por imagen , Enfermedad Trofoblástica Gestacional/complicaciones , Neoplasias Uterinas/diagnóstico por imagen , Periodo Posparto
3.
Nat Metab ; 5(3): 398-413, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36864206

RESUMEN

Whereas cholesterol is vital for cell growth, proliferation, and remodeling, dysregulation of cholesterol metabolism is associated with multiple age-related pathologies. Here we show that senescent cells accumulate cholesterol in lysosomes to maintain the senescence-associated secretory phenotype (SASP). We find that induction of cellular senescence by diverse triggers enhances cellular cholesterol metabolism. Senescence is associated with the upregulation of the cholesterol exporter ABCA1, which is rerouted to the lysosome, where it moonlights as a cholesterol importer. Lysosomal cholesterol accumulation results in the formation of cholesterol-rich microdomains on the lysosomal limiting membrane enriched with the mammalian target of rapamycin complex 1 (mTORC1) scaffolding complex, thereby sustaining mTORC1 activity to support the SASP. We further show that pharmacological modulation of lysosomal cholesterol partitioning alters senescence-associated inflammation and in vivo senescence during osteoarthritis progression in male mice. Our study reveals a potential unifying theme for the role of cholesterol in the aging process through the regulation of senescence-associated inflammation.


Asunto(s)
Inflamación , Lisosomas , Masculino , Animales , Ratones , Inflamación/metabolismo , Regulación hacia Arriba , Lisosomas/metabolismo , Senescencia Celular/fisiología , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Mamíferos/metabolismo
4.
Acute Crit Care ; 38(3): 382-388, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35791656

RESUMEN

Systemic glucocorticoid treatment is highly recommended in critically ill coronavirus disease 2019 (COVID-19) patients. However, secondary fungal infections are of concern in such patients. Here, we describe the first case of COVID-19-associated invasive pulmonary aspergillosis (CAPA) and COVID-19-associated mucormycosis (CAM) coinfection in a COVID-19 positive immunocompetent patient in Korea. A 69-year-old man was admitted to our hospital with COVID-19 pneumonia. He had no underlying comorbidities and was not taking medications. He received remdesivir, dexamethasone, and antibiotic therapy under mechanical ventilation. Although his condition improved temporarily, multiple cavities were observed on chest computed tomography, and Aspergillus fumigatus was cultured from tracheal aspiration culture. He was diagnosed with probable CAPA and received voriconazole therapy. However, his condition was not significantly improved despite having received voriconazole therapy for 4 weeks. After release from COVID-19 quarantine, he underwent bronchoscopy examination and was then finally diagnosed with CAPA and CAM coinfection on bronchoscopic biopsy. Antifungal treatment was changed to liposomal amphotericin B. However, his progress deteriorated, and he died 4 months after admission. This case highlights that clinical suspicion and active checkups are required to diagnose secondary fungal infections in immunocompetent COVID-19 patients who receive concurrent glucocorticoid therapy.

5.
J Pathol Transl Med ; 56(5): 281-288, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36128864

RESUMEN

BACKGROUND: The aim of the present study was to evaluate the prognostic significance of B-cell lymphocyte kinase (BLK) expression for survival outcomes in diffuse large B-cell lymphoma (DLBCL) patients treated with R-CHOP. METHODS: We retrospectively analyzed the medical records of 89 patients from two tertiary referral hospitals. The expression of BLK, SYK, and CDK1 were evaluated in a semiquantitative method using an H-score, and the proportions of BCL2 and C-MYC were evaluated. RESULTS: A total of 89 patients received R-CHOP chemotherapy as a first-line chemotherapy. The expression rates of BLK in tumor cells was 39.2% (n = 34). BLK expression status was not significantly associated with clinical variables; however, BLK expression in tumor cells was significantly associated with the expression of both C-MYC and BCL2 (p = .003). With a median follow-up of 60.4 months, patients with BLK expression had significantly lower 5-year progression-free survival (PFS) and overall survival rates (49.8% and 60.9%, respectively) than patients without BLK expression (77.3% and 86.7%, respectively). In multivariate analysis for PFS, BLK positivity was an independent poor prognostic factor (hazard ratio, 2.208; p = .040). CONCLUSIONS: Here, we describe the clinicopathological features and survival outcome according to expression of BLK in DLBCL. Approximately 39% of DLBCL patients showed BLK positivity, which was associated as a predictive marker for poor prognosis in patients who received R-CHOP chemotherapy.

6.
Transplant Proc ; 54(6): 1627-1631, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35811147

RESUMEN

INTRODUCTION: Malakoplakia is a rare pseudotumor that arises in the context of recurrent infections, particularly in immunocompromised states. We report a case of renal allograft parenchymal malakoplakia. CASE REPORT: A 59-year-old woman successfully received a cadaveric renal transplant in June 2018. Two months after transplantation, she was treated for a urinary tract infection (UTI). In March 2019, she underwent allograft biopsy for increasing creatinine. The biopsy identified T cell mediated rejection and steroid pulse therapy was performed. In December 2019, she was hospitalized for right flank pain and pyuria, and her creatinine level was 1.9 mg/dL. Radiographic findings were suggestive of a hematoma or abscess in the perirenal area, and septated fluid collection was suspected. Biopsy results suggested malakoplakia, and von Kossa stain was positive for Michaelis- Gutmann bodies. Tissue culture demonstrated Escherichia coli, and this was treated with antibiotics. The dose of tacrolimus was reduced. The patient was discharged after 1 month of hospitalization and was maintained on oral antibiotics. Follow-up imaging revealed an increase in the extent of lesion into the adjacent abdominal wall. Assuming the case to be refractory, we performed surgical resection and abscess drainage. Although the renal parenchymal involvement persisted, the size showed a decreasing trend over 2 months of serial observation with ultrasonography. CONCLUSIONS: Malakoplakia should be considered as a differential diagnosis for recurrent UTI with graft dysfunction. Malakoplakia can be successfully treated with reduction in immunosuppression and medical therapy using long-term antibiotic treatment in most cases. However, early surgical treatment must be considered for refractory cases.


Asunto(s)
Trasplante de Riñón , Malacoplasia , Infecciones Urinarias , Absceso , Antibacterianos/uso terapéutico , Creatinina , Femenino , Humanos , Trasplante de Riñón/efectos adversos , Malacoplasia/diagnóstico , Persona de Mediana Edad , Esteroides/uso terapéutico , Tacrolimus/uso terapéutico , Infecciones Urinarias/tratamiento farmacológico
7.
Clin Nucl Med ; 47(4): e375-e376, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35119394

RESUMEN

ABSTRACT: We report a case of amyloid arthropathy and pseudomyopathy with multiple myeloma, detected by amyloid PET/CT using 18F-florapronol. Bone scintigraphy and 18F-FDG PET/CT in a multiple myeloma patient revealed uneven soft tissue uptakes, especially at periarticular areas. The joint capsule and intermuscular fascia showed enhancement on CT, whereas muscle enzymes were normal. These suggested amyloid arthropathy with pseudomyopathy. 18F-Florapronol amyloid PET/CT showed extensive soft tissue uptakes. Amyloid arthropathy and pseudomyopathy were confirmed after biopsy. This is the first report of amyloid PET/CT aiding in the diagnosis of unusual presentation of systemic amyloidosis.


Asunto(s)
Amiloidosis , Artropatías , Mieloma Múltiple , Amiloidosis/complicaciones , Amiloidosis/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Humanos , Mieloma Múltiple/complicaciones , Mieloma Múltiple/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X
8.
J Nucl Med ; 63(10): 1586-1591, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35086893

RESUMEN

We aimed to explore whether the imaging of antiporter system xC - of immune cells with (4S)-4-(3-18F-fluoropropyl)-l-glutamate (18F-FSPG) PET can assess inflammatory bowel disease (IBD) activity in murine models and patients (NCT03546868). Methods: 18F-FSPG PET imaging was performed to assess IBD activity in mice with dextran sulfate sodium-induced and adoptive T-cell transfer-induced IBD and a cohort of 20 patients at a tertiary care center in South Korea. Immunohistochemical analysis of system xC - and cell surface markers was also studied. Results: Mice with experimental IBD showed increased intestinal 18F-FSPG uptake and xCT expression in cells positive (+) for CD11c, F4/80, and CD3 in the lamina propria, increases positively associated with clinical and pathologic disease activity. 18F-FSPG PET studies in patients, most of whom were clinically in remission or had mildly active IBD, showed that PET imaging was sufficiently accurate in diagnosing endoscopically active IBD and remission in patients and bowel segments. 18F-FSPG PET correctly identified all 9 patients with superficial or deep ulcers. Quantitative intestinal 18F-FSPG uptake was strongly associated with endoscopic indices of IBD activity. The number of CD68+xCT+ and CD3+xCT+ cells in 22 bowel segments from patients with ulcerative colitis and the number of CD68+xCT+ cells in 7 bowel segments from patients with Crohn disease showed a significant positive association with endoscopic indices of IBD activity. Conclusion: The assessment of system xC - in immune cells may provide diagnostic information on the immune responses responsible for chronic active inflammation in IBD. 18F-FSPG PET imaging of system xC - activity may noninvasively assess the IBD activity.


Asunto(s)
Ácido Glutámico , Enfermedades Inflamatorias del Intestino , Animales , Antiportadores , Sulfato de Dextran , Enfermedades Inflamatorias del Intestino/diagnóstico por imagen , Ratones , Tomografía de Emisión de Positrones/métodos
9.
Sci Total Environ ; 811: 152331, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-34915016

RESUMEN

Wastewater treatment plants (WWTPs) constantly receive a wide variety of contaminants, including pharmaceuticals, and are potential reservoirs of antibiotic resistance genes (ARGs). This favors the development of multidrug-resistant bacteria (MRB) through horizontal gene transfer. Samples from five different WWTP processes were collected in September 2020 and January 2021 to monitor ARG resistomes and culturable MRB in the presence of eight different antibiotics. Nanopore-based ARG abundance and bacterial community analyses suggested that ARG accumulation favors the generation of MRB. Activated and mixed sludges tended to have lower bacterial diversity and ARG abundance because of selective forces that favored the growth of specific microorganisms during aeration processes. Escherichia strains enriched in WWTPs (up to 71%) were dominant in all the samples, whereas Cloacamonas species were highly abundant only in anaerobically digested sludge samples (60%-79%). Two ARG types [sulfonamide resistance genes (sul1) and aminoglycoside resistance genes (aadA1, aadA13, and aadA2)] were prevalent in all the processes. The total counts of culturable MRB, such as Niabella, Enterococcus, Bacillus, and Chryseobacterium species, gradually increased during aerobic WWTP processes. Genomic analyses of all MRB isolated from the samples revealed that the resistome of Enterococcus species harbored the highest number of ARGs (7-18 ARGs), commonly encoding ant(6)-la, lnu(B), erm(B), and tet(S/M). On the other hand, Niablella strains possibly had intrinsic resistant phenotypes without ARGs. All MRB possessed ARGs originating from the same mobile genetic elements, suggesting that WWTPs are hotspots for the migration of ARGs and emergence of MRB.


Asunto(s)
Antibacterianos , Purificación del Agua , Antibacterianos/farmacología , Bacterias/genética , Farmacorresistencia Bacteriana Múltiple/genética , Genes Bacterianos , Aguas Residuales
10.
Nutrients ; 13(10)2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34684643

RESUMEN

The metabolic syndrome (MetS), defined as the co-occurrence of disorders including obesity, dyslipidemia, insulin resistance, and hepatic steatosis, has become increasingly prevalent in the world over recent decades. Dietary and other environmental factors interacting with genetic predisposition are likely contributors to this epidemic. Among the involved dietary factors, excessive fructose consumption may be a key contributor. When fructose is consumed in large amounts, it can quickly produce many of the features of MetS both in humans and mice. The mechanisms by which fructose contributes to metabolic disease and its potential interactions with genetic factors in these processes remain uncertain. Here, we generated a small F2 genetic cohort of male mice derived from crossing fructose-sensitive and -resistant mouse strains to investigate the interrelationships between fructose-induced metabolic phenotypes and to identify hepatic transcriptional pathways that associate with these phenotypes. Our analysis indicates that the hepatic transcriptional pathways associated with fructose-induced hypertriglyceridemia and hyperinsulinemia are distinct from those that associate with fructose-mediated changes in body weight and liver triglyceride. These results suggest that multiple independent mechanisms and pathways may contribute to different aspects of fructose-induced metabolic disease.


Asunto(s)
Fructosa/efectos adversos , Hiperinsulinismo/complicaciones , Hipertrigliceridemia/complicaciones , Hígado/metabolismo , Análisis de Sistemas , Triglicéridos/metabolismo , Animales , Estudios de Cohortes , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Haplotipos , Hiperinsulinismo/sangre , Hipertrigliceridemia/sangre , Insulina/sangre , Masculino , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Mutación Missense/genética , Fenotipo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Triglicéridos/sangre
11.
Korean J Gastroenterol ; 78(3): 183-187, 2021 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-34565788

RESUMEN

Accessory spleens are common congenital anatomic variations that are usually asymptomatic. On the other hand, they can be clinically significant if complicated by hemorrhage, torsion, or infarction. This paper describes a case of an infarcted accessory spleen in a 30-year-old male who presented with abdominal pain. Abdominal CT and MRI revealed an isolated mass, 4.5 cm in size, in the perisplenic area. An infarcted accessory spleen was suspected. The patient underwent laparoscopic accessory splenectomy. Histopathology identified the mass as splenic tissue that had undergone ischemic necrosis. A definitive diagnosis of an infarcted accessory spleen was made, and the patient was discharged on day 5 after surgery symptom-free.


Asunto(s)
Enfermedades del Bazo , Infarto del Bazo , Dolor Abdominal/diagnóstico , Dolor Abdominal/etiología , Adulto , Humanos , Masculino , Esplenectomía , Infarto del Bazo/diagnóstico
12.
STAR Protoc ; 2(3): 100809, 2021 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-34585148

RESUMEN

Senescent cells constantly experience stressful conditions and restrain their protein translation to cope with it. Here, we present a detailed protocol to measure the rate of global protein synthesis using L-azidohomoalanine (L-AHA)-based click chemistry in human senescent fibroblasts. We optimized several aspects of the procedure, including senescence induction, a flow cytometry analysis of senescent cells, and the duration of L-AHA incorporation. This protocol uses senescent human fibroblasts but can be applied to other types of cells or circumstances. For complete details on the use and execution of this protocol, please refer to Lee et al. (2021).


Asunto(s)
Senescencia Celular/fisiología , Citometría de Flujo/métodos , Biosíntesis de Proteínas/fisiología , Proteínas/análisis , Alanina/análogos & derivados , Alanina/análisis , Alanina/metabolismo , Animales , Línea Celular , Química Clic , Fibroblastos/citología , Fibroblastos/metabolismo , Células HEK293 , Humanos , Ratones , Proteínas/química , Proteínas/metabolismo
13.
Autophagy ; 17(10): 3260-3261, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34313530

RESUMEN

Macroautophagy/autophagy is a sophisticated quality control program that limits cellular damage and maintains homeostasis, being an essential part of several lifespan-promoting interventions. However, autophagy is also necessary for full establishment of cellular senescence, a causal factor for many age-related diseases and aging. What lies ahead of us to unravel such a paradoxical role of autophagy in senescence is to identify specific targets degraded by autophagy during senescence and determine their importance in the senescence regulatory network. Recently, we developed the "Selective autophagy substrates Identification Platform (SIP)" to advance these goals, providing a rich set of autophagy substrate proteins involved in senescence. Our study demonstrated that selective autophagy coordinates the stress support networks in senescent cells by degrading multiple regulatory components, echoing its homeostatic roles in normal cells. Targeting this type of selective autophagy might provide a unique opportunity to develop non-senescence addiction-based therapeutic strategies for senotherapy by disturbing the homeostatic state of senescent cells.


Asunto(s)
Autofagia , Macroautofagia , Senescencia Celular , Homeostasis
14.
Elife ; 102021 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-34180396

RESUMEN

Modification of the outer membrane charge by a polymyxin B (PMB)-induced PmrAB two-component system appears to be a dominant phenomenon in PMB-resistant Acinetobacter baumannii. PMB-resistant variants and many clinical isolates also appeared to produce outer membrane vesicles (OMVs). Genomic, transcriptomic, and proteomic analyses revealed that upregulation of the pmr operon and decreased membrane-linkage proteins (OmpA, OmpW, and BamE) are linked to overproduction of OMVs, which also promoted enhanced biofilm formation. The addition of OMVs from PMB-resistant variants into the cultures of PMB-susceptible A. baumannii and the clinical isolates protected these susceptible bacteria from PMB. Taxonomic profiling of in vitro human gut microbiomes under anaerobic conditions demonstrated that OMVs completely protected the microbial community against PMB treatment. A Galleria mellonella-infection model with PMB treatment showed that OMVs increased the mortality rate of larvae by protecting A. baumannii from PMB. Taken together, OMVs released from A. baumannii functioned as decoys against PMB.


Wrapped in a thick, protective outer membrane, Acinetobacter baumannii bacteria can sometimes cause serious infections when they find their way into human lungs and urinary tracts. Antibiotics are increasingly ineffective against this threat, which forces physicians to resort to polymyxin B, an old, positively-charged drug that 'sticks' to the negatively-charged proteins and fatty components at the surface of A. baumannii. Scientists have noticed that when bacteria are exposed to lethal drugs, they often react by releasing vesicles, small 'sacs' made of pieces of the outer membranes which can contain DNA or enzymes. How this strategy protects the cells against antibiotics such as polymyxin B remains poorly understood. To investigate this question, Park et al. examined different strains of A. baumannii, showing that bacteria resistant to polymyxin B had lower levels of outer membrane proteins but would release more vesicles. Adding vesicles from resistant strains to non-resistant A. baumannii cultures helped cells to survive the drugs. In fact, this protective effect extended to other species, shielding whole communities of bacteria against polymyxin B. In vivo, the vesicles protected bacteria in moth larvae infected with A. baumannii, leading to a higher death rate in the animals. Experiments showed that the negatively-charged vesicles worked as decoys, trapping the positively-charged polymyxin B away from its target. Taken together, the findings by Park et al. highlight a new strategy that allows certain strains of bacteria to protect themselves from antibiotics, while also benefitting the rest of the microbial community.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/fisiología , Polimixina B/farmacología , Adulto , Animales , Antibacterianos/farmacología , Biopelículas , Farmacorresistencia Bacteriana , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Heces/microbiología , Femenino , Humanos , Larva/microbiología , Lípido A , Microscopía Electrónica de Transmisión , Mariposas Nocturnas/microbiología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
15.
J Microbiol ; 59(6): 535-545, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33877574

RESUMEN

The emergence of multidrug resistance (MDR) has become a global health threat due to the increasing unnecessary use of antibiotics. Multidrug resistant bacteria occur mainly by accumulating resistance genes on mobile genetic elements (MGEs), made possible by horizontal gene transfer (HGT). Humans and animal guts along with natural and engineered environments such as wastewater treatment plants and manured soils have proven to be the major reservoirs and hotspots of spreading antibiotic resistance genes (ARGs). As those environments support the dissemination of MGEs through the complex interactions that take place at the human-animal-environment interfaces, a growing One Health challenge is for multiple sectors to communicate and work together to prevent the emergence and spread of MDR bacteria. However, maintenance of ARGs in a bacterial chromosome and/or plasmids in the environments might place energy burdens on bacterial fitness in the absence of antibiotics, and those unnecessary ARGs could eventually be lost. This review highlights and summarizes the current investigations into the gain and loss of ARG genes in MDR bacteria among human-animal-environment interfaces. We also suggest alternative treatments such as combinatory therapies or sequential use of different classes of antibiotics/adjuvants, treatment with enzyme-inhibitors, and phage therapy with antibiotics to solve the MDR problem from the perspective of One Health issues.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana Múltiple , Animales , Bacterias/genética , Bacterias/metabolismo , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Proteínas Bacterianas/metabolismo , Humanos , Salud Única
16.
Dev Cell ; 56(10): 1512-1525.e7, 2021 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-33915088

RESUMEN

Cellular senescence is a complex stress response implicated in aging. Autophagy can suppress senescence but is counterintuitively necessary for full senescence. Although its anti-senescence role is well described, to what extent autophagy contributes to senescence establishment and the underlying mechanisms is poorly understood. Here, we show that selective autophagy of multiple regulatory components coordinates the homeostatic state of senescence. We combined a proteomic analysis of autophagy components with protein stability profiling, identifying autophagy substrate proteins involved in several senescence-related processes. Selective autophagy of KEAP1 promoted redox homeostasis during senescence. Furthermore, selective autophagy limited translational machinery components to ameliorate senescence-associated proteotoxic stress. Lastly, selective autophagy of TNIP1 enhanced senescence-associated inflammation. These selective autophagy networks appear to operate in vivo senescence during human osteoarthritis. Our data highlight a caretaker role of autophagy in the stress support network of senescence through regulated protein stability and unravel the intertwined relationship between two important age-related processes.


Asunto(s)
Autofagia , Senescencia Celular , Proteínas de Unión al ADN/metabolismo , Progresión de la Enfermedad , Factor 3 de Iniciación Eucariótica/metabolismo , Células HEK293 , Humanos , Inflamación/patología , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Modelos Biológicos , Osteoartritis/metabolismo , Osteoartritis/patología , Estrés Oxidativo , Proteostasis
17.
Adv Cancer Res ; 150: 75-112, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33858601

RESUMEN

Autophagy and cellular senescence are two potent tumor suppressive mechanisms activated by various cellular stresses, including the expression of activated oncogenes. However, emerging evidence has also indicated their pro-tumorigenic activities, strengthening the case for the complexity of tumorigenesis. More specifically, tumorigenesis is a systemic process emanating from the combined accumulation of changes in the tumor support pathways, many of which cannot cause cancer on their own but might still provide excellent therapeutic targets for cancer treatment. In this review, we discuss the dual roles of autophagy and senescence during tumorigenesis, with a specific focus on the stress support networks in cancer cells modulated by these processes. A deeper understanding of such context-dependent roles may help to enhance the effectiveness of cancer therapies targeting autophagy and senescence, while limiting their potential side effects. This will steer and accelerate the pace of research and drug development for cancer treatment.


Asunto(s)
Autofagia/fisiología , Senescencia Celular/fisiología , Neoplasias/terapia , Estrés Fisiológico/fisiología , Carcinogénesis/genética , Carcinogénesis/metabolismo , Carcinogénesis/patología , Daño del ADN/fisiología , Redes Reguladoras de Genes/fisiología , Humanos , Redes y Vías Metabólicas/genética , Redes y Vías Metabólicas/fisiología , Terapia Molecular Dirigida/métodos , Terapia Molecular Dirigida/tendencias , Neoplasias/genética , Neoplasias/patología
18.
Virulence ; 12(1): 150-164, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33372826

RESUMEN

Polymyxin B (PMB) is increasingly used as a last-line antibiotic; however, the emergence of PMB resistance is a serious threat to global health. Here, a total of 40 Acinetobacter baumannii clinical isolates were collected to screen for PMB-resistant strains. Several clinical isolates including NCCP 16007 were far more resistant to PMB (MIC: 128-256 µg/ml) than the ATCC 17978 strain (MIC: 2 µg/ml) and appeared to possess resistance to broad-spectrum antibiotics including meropenem and 12 others. Four highly PMB-resistant strains possessed point mutations in the histidine kinase PmrB, leading to an increased expression of pmrC encoding a phosphoethanolamine transferase. Whole-genome analyses revealed that the NCCP 16007 stain had acquired two additional copies of the pmrC gene with phage integrase and 13 antibiotic resistance genes (ARGs) from other pathogens, including Klebsiella pneumoniae and Pseudomonas aeruginosa. The GC ratios of the ARGs (50-60%) were higher than that of the chromosomal backbone (39.06%), further supporting the horizontal gene transfer of ARGs. Comparative genomics with other multidrug-resistant A. baumannii strains revealed that the NCCP 16007 strain has many additional ARGs and has lost several virulence factors including Csu pili and heme oxygenase but exhibited high pathogenicity in Galleria mellonella-infection models. The observation of condensed biofilm through confocal and scanning electron microscopy suggested that the NCCP 16007 strain may possess high adhesion capacity during urinary tract infection. Therefore, our genomic and phenotypic analyses suggested that the multidrug-resistant A. baumannii NCCP 16007 strain possesses high genome plasticity, natural transformation ability, and pathogenicity.


Asunto(s)
Infecciones por Acinetobacter/orina , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/genética , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Genoma Bacteriano , Fenotipo , Infecciones Urinarias/microbiología , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/clasificación , Acinetobacter baumannii/patogenicidad , Animales , Proteínas Bacterianas/genética , Biopelículas , Transferencia de Gen Horizontal , Genómica , Humanos , Larva/microbiología , Pruebas de Sensibilidad Microbiana , Mariposas Nocturnas/microbiología
19.
J Pathol Transl Med ; 54(4): 340-345, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32702946

RESUMEN

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), is one of the specific type of low-grade B-cell lymphoma not infrequently found worldwide. It typically involves mucosal sites such as stomach and conjunctiva; however, primary hepatic MALT lymphoma has been extremely rarely reported. We describe a case of hepatic MALT lymphoma in a 70-year-old male patient who underwent left hepatectomy due to the incidentally detected liver masses at a medical checkup. The resected specimen revealed multinodular masses consisting of small-to-intermediate-sized lymphoid cells with serpentine pattern and focal lymphoepithelial lesions. The tumor cells were diffusely positive for CD20 and Bcl-2 but negative for CD3, CD10, CD5, CD23, CD43, and cyclinD1. The Ki-67 labeling index was 10% and immunoglobulin heavy chain gene rearrangement study confirmed monoclonal proliferation. In this paper, we discuss several unique clinicopathologic characteristics which will be helpful to the differential diagnosis of hepatic MALT lymphoma.

20.
Hepatol Commun ; 4(5): 670-680, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32363318

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is a heterogeneous disease driven by genetic and environmental factors. MicroRNAs (miRNAs) serve as pleiotropic post-transcriptional regulators of cellular pathways. Although several miRNAs have been associated with NAFLD and fibrosis, there are limited studies in humans examining their differential association with pathogenic factors or histological features of NAFLD. We examined the differential relationships of five of the best-described circulating microRNAs (miR-34a, miR-122, miR-191, miR-192, and miR-200a) with histological features and pathogenic factors of NAFLD. A cross-sectional study was conducted to examine the relationship between relative levels of circulating microRNAs standardized by z-scores and histological features of NAFLD, common NAFLD genetic polymorphisms, and insulin resistance measured by the enhanced lipoprotein insulin resistance index in 132 subjects with biopsy-proven NAFLD. We found that miR-34a, miR-122, miR-192, miR-200a, but not miR-191, strongly correlate with fibrosis in NAFLD by increases of 0.20 to 0.40 SD (P < 0.005) with each stage of fibrosis. In multivariate analysis, miR-34a, miR-122, and miR-192 levels are independently associated with hepatic steatosis and fibrosis, but not lobular inflammation or ballooning degeneration, whereas miR-200a is only associated with fibrosis. Among the four miRNAs, miR-34a, miR-122, and miR-192 are associated with pathogenic factors of NAFLD, including insulin resistance measured by eLP-IR, patatin-like phospholipase domain containing 3 I148M, and transmembrane 6 superfamily 2 (TM6SF2) E167K polymorphisms. In contrast, miR-200a is only associated with the TM6SF2 E167K variant. Finally, miR-34a has the strongest predictive value for various stages of fibrosis, with C-statistic approximates-combined predictive score for miRNAs. Conclusion: miR-34a, miR-122, miR-192, and miR-200a demonstrate strong associations with NAFLD severity by histology, but differential associations with pathogenic factors.

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