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1.
J Biol Chem ; 300(7): 107437, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38838776

RESUMEN

Together with its ß-subunit OSTM1, ClC-7 performs 2Cl-/H+ exchange across lysosomal membranes. Pathogenic variants in either gene cause lysosome-related pathologies, including osteopetrosis and lysosomal storage. CLCN7 variants can cause recessive or dominant disease. Different variants entail different sets of symptoms. Loss of ClC-7 causes osteopetrosis and mostly neuronal lysosomal storage. A recently reported de novo CLCN7 mutation (p.Tyr715Cys) causes widespread severe lysosome pathology (hypopigmentation, organomegaly, and delayed myelination and development, "HOD syndrome"), but no osteopetrosis. We now describe two additional HOD individuals with the previously described p.Tyr715Cys and a novel p.Lys285Thr mutation, respectively. Both mutations decreased ClC-7 inhibition by PI(3,5)P2 and affected residues lining its binding pocket, and shifted voltage-dependent gating to less positive potentials, an effect partially conferred to WT subunits in WT/mutant heteromers. This shift predicts augmented pH gradient-driven Cl- uptake into vesicles. Overexpressing either mutant induced large lysosome-related vacuoles. This effect depended on Cl-/H+-exchange, as shown using mutants carrying uncoupling mutations. Fibroblasts from the p.Y715C patient also displayed giant vacuoles. This was not observed with p.K285T fibroblasts probably due to residual PI(3,5)P2 sensitivity. The gain of function caused by the shifted voltage-dependence of either mutant likely is the main pathogenic factor. Loss of PI(3,5)P2 inhibition will further increase current amplitudes, but may not be a general feature of HOD. Overactivity of ClC-7 induces pathologically enlarged vacuoles in many tissues, which is distinct from lysosomal storage observed with the loss of ClC-7 function. Osteopetrosis results from a loss of ClC-7, but osteoclasts remain resilient to increased ClC-7 activity.


Asunto(s)
Canales de Cloruro , Enfermedades por Almacenamiento Lisosomal , Lisosomas , Humanos , Masculino , Canales de Cloruro/genética , Canales de Cloruro/metabolismo , Mutación con Ganancia de Función , Células HEK293 , Enfermedades por Almacenamiento Lisosomal/genética , Enfermedades por Almacenamiento Lisosomal/metabolismo , Enfermedades por Almacenamiento Lisosomal/patología , Lisosomas/metabolismo , Lisosomas/genética , Proteínas de la Membrana , Mutación Missense , Fosfatos de Fosfatidilinositol/metabolismo , Ubiquitina-Proteína Ligasas , Vacuolas/metabolismo , Vacuolas/genética , Vacuolas/patología
2.
Acta Neuropathol ; 147(1): 86, 2024 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-38758288

RESUMEN

Dominantly inherited mutation D395G in the gene encoding valosin-containing protein causes vacuolar tauopathy, a type of behavioural-variant frontotemporal dementia, with marked vacuolation and abundant filamentous tau inclusions made of all six brain isoforms. Here we report that tau inclusions were concentrated in layers II/III of the frontotemporal cortex in a case of vacuolar tauopathy. By electron cryomicroscopy, tau filaments had the chronic traumatic encephalopathy (CTE) fold. Tau inclusions of vacuolar tauopathy share this cortical location and the tau fold with CTE, subacute sclerosing panencephalitis and amyotrophic lateral sclerosis/parkinsonism-dementia complex, which are believed to be environmentally induced. Vacuolar tauopathy is the first inherited disease with the CTE tau fold.


Asunto(s)
Encefalopatía Traumática Crónica , Mutación , Tauopatías , Proteína que Contiene Valosina , Proteínas tau , Humanos , Tauopatías/genética , Tauopatías/patología , Encefalopatía Traumática Crónica/patología , Encefalopatía Traumática Crónica/genética , Proteínas tau/genética , Proteínas tau/metabolismo , Proteína que Contiene Valosina/genética , Vacuolas/patología , Vacuolas/ultraestructura , Masculino , Adenosina Trifosfatasas/genética , Proteínas de Ciclo Celular/genética , Persona de Mediana Edad , Demencia Frontotemporal/genética , Demencia Frontotemporal/patología , Encéfalo/patología , Femenino
3.
BMC Ophthalmol ; 24(1): 227, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811878

RESUMEN

OBJECTIVE: To present six cases exhibiting transient anterior subcapsular vacuolar lens opacities following early postoperative Tanito microhook trabeculotomy (TMH) performed by the same surgeon. METHODS: Six patients who underwent lens-sparing TMH at Meizankai Shimizu Eye Clinic from November 2021 to May 2023, and developed anterior subcapsular vacuolar lens opacities postoperatively were reviewed. Detailed records of surgeries, follow-up findings were collected and reported. RESULTS: In all six cases, anterior vacuolar subcapsular lens opacities were observed on the day after surgery, gradually decreasing without affecting visual acuity or contrast sensitivity. In all cases, without any specific interventions, the opacities disappeared by 21 months postoperatively. CONCLUSION: Anterior subcapsular cataracts, characterized by a vacuolar appearance and transient existence, should be recognized as an early complication of ab interno glaucoma surgery, possibly linked to use of distributed ophthalmic viscosurgical devices and excessive anterior chamber irrigation leading to traumatic cataracts on the lens surface.


Asunto(s)
Catarata , Trabeculectomía , Agudeza Visual , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Glaucoma/cirugía , Presión Intraocular/fisiología , Cápsula del Cristalino/cirugía , Cápsula del Cristalino/patología , Complicaciones Posoperatorias , Estudios Retrospectivos , Trabeculectomía/efectos adversos , Vacuolas/patología
4.
Am J Dermatopathol ; 46(10): 637-647, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39293663

RESUMEN

ABSTRACT: We present the histopathology of 12 skin biopsies from 6 patients with vacuoles, enzyme E1, X-linked, autoinflammatory, somatic syndrome and review the literature. The age of these 6 men ranges from 62 to 83 years (median of 70 years). UBA1 mutation was documented in all 6 patients. Multiple organ systems were involved with constitutional symptoms noted in 4 of 6 patients (67%), cutaneous involvement in 6 of 6 patients (100%), hematologic abnormalities in 6 of 6 patients (100%), pulmonary involvement in 4 of 6 patients (67%), musculoskeletal abnormalities in 3 of 6 patients (50%), vascular thrombosis in 2 of 6 patients (33%), ocular involvement in 2 of 6 patients (33%), and gastrointestinal involvement in 5 of 6 patients (83%). Of the 6 presented patients, neutrophilic dermatosis was seen in 3 biopsies, histiocytoid neutrophilic dermatosis in 1 biopsy, neutrophilic dermatosis with vasculitis in 1 biopsy, neutrophilic and granulomatous dermatitis in 2 biopsies, septal panniculitis consistent with erythema nodosum in 2 biopsies, and nonspecific patterns in 3 biopsies. In summary, neutrophilic dermatosis, small-vessel vasculitis, and panniculitis are frequent histopathologic patterns noted in decreasing frequency in skin biopsies of the patients with vacuoles, enzyme E1, X-linked, autoinflammatory, somatic syndrome. However, the histopathologic findings can be diverse, nonspecific in some instances, and varied among different biopsies obtained from the same patient.


Asunto(s)
Vacuolas , Humanos , Masculino , Persona de Mediana Edad , Anciano , Biopsia , Anciano de 80 o más Años , Vacuolas/patología , Enzimas Activadoras de Ubiquitina/genética , Piel/patología , Mutación , Síndrome , Enfermedades Genéticas Ligadas al Cromosoma X/patología , Enfermedades Genéticas Ligadas al Cromosoma X/genética
5.
BMC Musculoskelet Disord ; 25(1): 257, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566087

RESUMEN

BACKGROUND: A few patients with inflammatory myopathy showed anti-mitochondrial antibody (AMA) positivity. This study aimed to report the clinical and pathological findings with vacuoles in 3 cases of such patients. METHODS: Three cases with myositis from the Myositis Clinical Database of Peking University First Hospital were identified with AMA positivity. Their clinical records were retrospectively reviewed and the data was extracted. All the 3 cases underwent muscle biopsy. RESULTS: Three middle-aged patients presented with chronic-onset weakness of proximal limbs, marked elevation of creatine kinase, and AMA-positivity. Two of the 3 cases meet the criteria of primary biliary cholangitis. All the 3 cases presented with cardiac involvement and proteinuria. Two cases developed type 2 respiratory failure. MRI of the thigh muscle showed multiple patches of edema bilaterally in both cases, mostly in the adductor magnus. Pathological findings include degeneration of muscle fibers, diffused MHC-I positivity, and complement deposits on cell membranes. Vacuoles without rims of different sizes were discovered under the membrane of the muscle fibers. A few RBFs were discovered in case 1, while a diffused proliferation of endomysium and perimysium was shown in case 2. CONCLUSIONS: AMA-positive inflammatory myopathy is a disease that could affect multiple systems. Apart from inflammatory changes, the pathological findings of muscle can also present vacuoles.


Asunto(s)
Enfermedades Musculares , Miositis , Persona de Mediana Edad , Humanos , Vacuolas/patología , Estudios Retrospectivos , Miositis/complicaciones , Miositis/diagnóstico por imagen , Miositis/tratamiento farmacológico , Enfermedades Musculares/diagnóstico por imagen , Enfermedades Musculares/patología , Músculo Esquelético/patología , Anticuerpos/uso terapéutico , Antiinflamatorios/uso terapéutico , Autoanticuerpos
6.
Zhonghua Bing Li Xue Za Zhi ; 53(9): 910-915, 2024 Sep 08.
Artículo en Zh | MEDLINE | ID: mdl-39231743

RESUMEN

Objective: To investigate the clinicopathological features and differential diagnosis of eosinophilic vacuolated tumor (EVT). Methods: Seven cases of EVT with characteristic morphology and unequivocal diagnosis from the Affiliated Hospital of Qingdao University (6 cases), Qingdao, China and the 971 Hospital of PLA Navy (1 case), Qingdao, China between January 2010 and December 2021 were subject to morphological and immunohistochemical analyses. Additionally, whole exome sequencing (WES) was performed in two cases. Twenty-two cases of renal oncocytoma (RO) and 17 cases of eosinophilic chromophobe renal cell carcinoma (eChRCC) diagnosed at the same time were used as controls. Results: Four males and three females with a mean age of 42 years (range: 29-61 years) were included in the study. The tumors were nodular and well-circumscribed, with sizes ranging from 1.5 to 4.5 cm. On cross-section, they appeared gray-red or gray-white, solid, and soft. Tumor cells were arranged in nests, solid sheets, and acinar or small vesicular structures. These cells exhibited eosinophilic cytoplasm with large, prominent clear vacuoles and round nuclei with prominent nucleoli. Perinuclear halos were focally present in four cases, while small tumor cells with sparse cytoplasm and hyperchromatic nuclei were seen in one case. No necrosis or mitosis was noted. Edematous stroma was detected in three cases. All tumors were positive for CD117 and Cathepsin K, but negative for vimentin and CK7. CK20 was positive in scattered individual cells, and Ki-67 positivity ranged from 1% to 4%. Point mutations in MTOR were identified in both patients who were subject to the molecular analysis. Statistical differences in the expression of Cathepsin K, CD10, S-100A1, and Cyclin D1 between EVT and RO (P<0.05) were significant, so were the differences in the expression of Cathepsin K, CD10, CK7 and claudin 7 between EVT and eChRCC (P<0.001). Seven patients were followed up for 4 to 96 months (mean, 50 months), with no recurrences or metastases. Conclusions: EVT is a rare renal tumor that shares morphological and immunophenotypic features with RO and eChRCC, and it is closely linked to the TSC/MTOR pathway. The presence of large prominent transparent vacuoles in eosinophilic cytoplasm along with conspicuous nucleoli is its key morphological characteristics. The use of combined immunohistochemical stains greatly aids in its diagnosis. Typically, the tumor exhibits indolent biological behaviors with a favorable prognosis.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Neoplasias Renales/patología , Neoplasias Renales/metabolismo , Neoplasias Renales/genética , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/genética , Diagnóstico Diferencial , Vacuolas/patología , Eosinófilos/patología , Eosinofilia/patología , Eosinofilia/metabolismo
7.
PLoS Pathog ; 17(4): e1009550, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33930101

RESUMEN

Salmonella Typhimurium (S. Typhimurium) is an enteric bacterium capable of invading a wide range of hosts, including rodents and humans. It targets different host cell types showing different intracellular lifestyles. S. Typhimurium colonizes different intracellular niches and is able to either actively divide at various rates or remain dormant to persist. A comprehensive tool to determine these distinct S. Typhimurium lifestyles remains lacking. Here we developed a novel fluorescent reporter, Salmonella INtracellular Analyzer (SINA), compatible for fluorescence microscopy and flow cytometry in single-bacterium level quantification. This identified a S. Typhimurium subpopulation in infected epithelial cells that exhibits a unique phenotype in comparison to the previously documented vacuolar or cytosolic S. Typhimurium. This subpopulation entered a dormant state in a vesicular compartment distinct from the conventional Salmonella-containing vacuoles (SCV) as well as the previously reported niche of dormant S. Typhimurium in macrophages. The dormant S. Typhimurium inside enterocytes were viable and expressed Salmonella Pathogenicity Island 2 (SPI-2) virulence factors at later time points. We found that the formation of these dormant S. Typhimurium is not triggered by the loss of SPI-2 effector secretion but it is regulated by (p)ppGpp-mediated stringent response through RelA and SpoT. We predict that intraepithelial dormant S. Typhimurium represents an important pathogen niche and provides an alternative strategy for S. Typhimurium pathogenicity and its persistence.


Asunto(s)
Células Epiteliales/microbiología , Infecciones por Salmonella/microbiología , Salmonella typhimurium/fisiología , Latencia del Virus/fisiología , Células 3T3 , Animales , Células CACO-2 , Células Epiteliales/patología , Islas Genómicas/genética , Células HeLa , Humanos , Ratones , Infecciones por Salmonella/patología , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidad , Células THP-1 , Vacuolas/microbiología , Vacuolas/patología , Factores de Virulencia/genética , Latencia del Virus/genética
8.
Ann Neurol ; 91(4): 568-574, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35148013

RESUMEN

Coronavirus disease 2019 (COVID-19) severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2 infection) can lead to intensive care unit (ICU) admission and critical illness myopathy (CIM). We examined 3 ICU patients with COVID-19 who required mechanical ventilation for pneumonia and developed CIM. Pathological examination of the skeletal muscle biopsies revealed myopathic changes consistent with CIM, variable inflammation with autophagic vacuoles, SARS-CoV immunostaining + fibers/granules, and electron microscopy findings of mitochondrial abnormalities and coronavirus-like particles. Although mitochondrial dysfunction with compromised energy production is a critical pathogenic mechanism of non-COVID-19-associated CIM, in our series of COVID-19-associated CIM, myopathic changes including prominent mitochondrial damage suggest a similar mechanism and association with direct SARS-CoV-2 muscle infection. ANN NEUROL 2022;91:568-574.


Asunto(s)
COVID-19/complicaciones , COVID-19/virología , Enfermedad Crítica , Enfermedades Musculares/etiología , Enfermedades Musculares/virología , SARS-CoV-2 , Adulto , Anciano , Autofagia , Resultado Fatal , Femenino , Humanos , Inflamación/patología , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Mitocondrias/patología , Músculo Esquelético/patología , Vacuolas/patología
9.
Cytopathology ; 34(5): 503-506, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36840426

RESUMEN

Chordoma is a rare primary central nervous system tumour of notochordal origin. Proper intraoperative or preoperative diagnosis of this entity is crucial for appropriate surgical management. The most common histopathological subtype is conventional chordoma. Cytological characteristics of this subtype are quite distinctive and the diagnosis can be easily made by cytology. There are two particularly important features that are observed in both squash smear and fine needle aspiration specimens: an abundant myxochondroid stroma and cells with large vacuoles, including physaliferous cells. The main differential diagnosis is conventional chondrosarcoma, but in problematic cases immunohistochemical studies are useful to establish the correct diagnosis.


Asunto(s)
Cordoma , Humanos , Biopsia con Aguja Fina , Cordoma/diagnóstico , Cordoma/patología , Vacuolas/patología , Diagnóstico Diferencial , Citodiagnóstico
10.
J Biol Chem ; 297(6): 101340, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34695417

RESUMEN

Legionella pneumophila is a facultative intracellular pathogen that uses the Dot/Icm Type IV secretion system (T4SS) to translocate many effectors into its host and establish a safe, replicative lifestyle. The bacteria, once phagocytosed, reside in a vacuolar structure known as the Legionella-containing vacuole (LCV) within the host cells and rapidly subvert organelle trafficking events, block inflammatory responses, hijack the host ubiquitination system, and abolish apoptotic signaling. This arsenal of translocated effectors can manipulate the host factors in a multitude of different ways. These proteins also contribute to bacterial virulence by positively or negatively regulating the activity of one another. Such effector-effector interactions, direct and indirect, provide the delicate balance required to maintain cellular homeostasis while establishing itself within the host. This review summarizes the recent progress in our knowledge of the structure-function relationship and biochemical mechanisms of select effector pairs from Legionella that work in opposition to one another, while highlighting the diversity of biochemical means adopted by this intracellular pathogen to establish a replicative niche within host cells.


Asunto(s)
Interacciones Huésped-Patógeno , Legionella pneumophila/fisiología , Enfermedad de los Legionarios/metabolismo , Animales , Proteínas Bacterianas/metabolismo , Homeostasis , Humanos , Inflamación/metabolismo , Inflamación/microbiología , Inflamación/patología , Enfermedad de los Legionarios/microbiología , Enfermedad de los Legionarios/patología , Sistemas de Secreción Tipo IV/metabolismo , Ubiquitinación , Vacuolas/metabolismo , Vacuolas/microbiología , Vacuolas/patología
11.
Clin Exp Dermatol ; 47(4): 765-767, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34856003

RESUMEN

An 83-year-old woman was referred to the Dermatology department with a papular eruption on her left arm, occurring below the scar site of a malignant melanoma in situ, which had been excised 6 months previously. On physical examination, multiple, tender, violaceous papules and nodules inferior to the scar were noted, with central pustules in some of the lesions.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Anciano de 80 o más Años , Femenino , Granuloma , Humanos , Neoplasias Cutáneas/patología , Supuración , Vacuolas/patología
12.
Proc Natl Acad Sci U S A ; 116(49): 24583-24592, 2019 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-31732667

RESUMEN

The mammalian target of rapamycin (mTOR) pathway, which plays a critical role in regulating cellular growth and metabolism, is aberrantly regulated in the pathogenesis of a variety of neoplasms. Here we demonstrate that dual mTORC1/mTORC2 inhibitors OSI-027 and PP242 cause catastrophic macropinocytosis in rhabdomyosarcoma (RMS) cells and cancers of the skin, breast, lung, and cervix, whereas the effects are much less pronounced in immortalized human keratinocytes. Using RMS as a model, we characterize in detail the mechanism of macropinocytosis induction. Macropinosomes are distinct from endocytic vesicles and autophagosomes in that they are single-membrane bound vacuoles formed by projection, ruffling, and contraction of plasma membranes. They are positive for EEA-1 and LAMP-1 and contain watery fluid but not organelles. The vacuoles then merge and rupture, killing the cells. We confirmed the inhibition of mTORC1/mTORC2 as the underpinning mechanism for macropinocytosis. Exposure to rapamycin, an mTORC1 inhibitor, or mTORC2 knockdown alone had little or reduced effect relative to the combination. We further demonstrate that macropinocytosis depends on MKK4 activated by elevated reactive oxygen species. In a murine xenograft model, OSI-027 reduced RMS tumor growth. Molecular characterization of the residual tumors was consistent with the induction of macropinocytosis. Furthermore, relative to the control xenograft tumors, the residual tumors manifested reduced expression of cell proliferation markers and proteins that drive the epithelial mesenchymal transition. These data indicate a role of mTORC2 in regulating tumor growth by macropinocytosis and suggest that dual inhibitors could help block refractory or recurrent RMS and perhaps other neoplasms and other cancer as well.


Asunto(s)
Antineoplásicos/farmacología , Imidazoles/farmacología , Indoles/farmacología , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Diana Mecanicista del Complejo 2 de la Rapamicina/antagonistas & inhibidores , Pinocitosis/efectos de los fármacos , Purinas/farmacología , Triazinas/farmacología , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Línea Celular Tumoral , Ciclofosfamida/administración & dosificación , Transición Epitelial-Mesenquimal/efectos de los fármacos , Femenino , Humanos , Imidazoles/administración & dosificación , MAP Quinasa Quinasa 4/metabolismo , Ratones Desnudos , Rabdomiosarcoma/tratamiento farmacológico , Rabdomiosarcoma/patología , Triazinas/administración & dosificación , Vacuolas/efectos de los fármacos , Vacuolas/patología , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Neurobiol Dis ; 147: 105138, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33069844

RESUMEN

Neurofibrillary tangles arising from aggregated microtubule-associated protein tau occur in aged brains and are hallmarks of neurodegenerative diseases. A subset of neurons containing aggregated tau displays granulovacuolar degeneration (GVD) that is characterized by membrane-bound cytoplasmic vacuoles, each containing an electron-dense granule (GVB). Tau pathology induces GVBs in experimental models, but GVD does not generally follow tau pathology in the human brain. The entorhinal cortex, DRN, and LC are among the regions that display pathological changes of tau earliest, whereas neurons with GVBs occur first in the hippocampus and have been found in oral raphe nuclei only at the most advanced GVD stage. To date, there is no detailed report about neurons with GVD in aminergic nuclei. We studied the relation between tau pathology and GVD in field CA1 of the hippocampus, entorhinal cortex, dorsal (DRN) and median (MRN) raphe nucleus, and locus coeruleus from elderly subjects with Braak & Braak stages of tau pathology ranging from 0 to VI. Tau pathology and GVBs were visualized by means of immunolabeling and quantified. Percentages of neurons containing GVBs were significantly related to percentages of AT8-positive neurons in the regions examined. GVD and tau pathology were found together in neurons to a different extent in regions of the brain. 53.2% of AT8-immunoreactive neurons in CA1, 19.8% in layer II of the entorhinal cortex, 29.6% in the DRN, and 31.4% in the locus coeruleus contained GVBs. Age-related factors, the percentage of neurons with pretangles in a region of the brain, and the metabolism of a neuron possibly influence the prevalence of neurons with GVBs.


Asunto(s)
Encéfalo/patología , Degeneración Nerviosa/patología , Ovillos Neurofibrilares/patología , Neuronas/patología , Tauopatías/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ovillos Neurofibrilares/metabolismo , Vacuolas/patología , Proteínas tau/metabolismo
14.
Neurobiol Dis ; 148: 105215, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33296728

RESUMEN

We previously showed that optineurin (OPTN) mutations lead to the development of amyotrophic lateral sclerosis. The association between OPTN mutations and the pathogenesis of amyotrophic lateral sclerosis remains unclear. To investigate the mechanism underlying its pathogenesis, we generated Optn knockout mice. We evaluated histopathological observations of these mice and compared with those of OPTN- amyotrophic lateral sclerosis cases to investigate the mechanism underlying the pathogenesis of amyotrophic lateral sclerosis caused by OPTN mutations. The Optn (-/-) mice presented neuronal autophagic vacuoles immunopositive for charged multivesicular body protein 2b, one of the hallmarks of granulovacuolar degenerations, in the cytoplasm of spinal cord motor neurons at the age of 8 months and the OPTN- amyotrophic lateral sclerosis case with homozygous Q398X mutation. In addition, Optn (-/-) mice showed TAR-DNA binding protein 43/sequestosome1/p62 -positive cytoplasmic inclusions and the clearance of nuclear TAR-DNA binding protein 43. The axonal degeneration of the sciatic nerves was observed in Optn (-/-) mice. However, we could not observe significant differences in survival time, body weight, and motor functions, at 24 months. Our findings suggest that homozygous OPTN deletion or mutations might result in autophagic dysfunction and TAR-DNA binding protein 43 mislocalization, thereby leading to neurodegeneration of motor neurons. These findings indicate that the Optn (-/-) mice recapitulate both common and specific pathogenesis of amyotrophic lateral sclerosis associated with autophagic abnormalities. Optn (-/-) mice could serve as a mouse model for the development of therapeutic strategies.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Autofagia/genética , Proteínas de Ciclo Celular/genética , Proteínas de Unión al ADN/metabolismo , Hipocampo/metabolismo , Proteínas de Transporte de Membrana/genética , Neocórtex/metabolismo , Médula Espinal/metabolismo , Vacuolas/metabolismo , Anciano de 80 o más Años , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/patología , Esclerosis Amiotrófica Lateral/fisiopatología , Animales , Hipocampo/patología , Humanos , Ratones , Ratones Noqueados , Persona de Mediana Edad , Cuerpos Multivesiculares/metabolismo , Neocórtex/patología , Médula Espinal/patología , Vacuolas/patología
15.
J Cell Sci ; 132(21)2019 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-31558680

RESUMEN

Cells depend on a highly ordered organisation of their content and must develop strategies to maintain the anisotropic distribution of organelles during periods of nutrient shortage. One of these strategies is to solidify the cytoplasm, which was observed in bacteria and yeast cells with acutely interrupted energy production. Here, we describe a different type of cytoplasm solidification fission yeast cells switch to, after having run out of nutrients during multiple days in culture. It provides the most profound reversible cytoplasmic solidification of yeast cells described to date. Our data exclude the previously proposed mechanisms for cytoplasm solidification in yeasts and suggest a mechanism that immobilises cellular components in a size-dependent manner. We provide experimental evidence that, in addition to time, cells use intrinsic nutrients and energy sources to reach this state. Such cytoplasmic solidification may provide a robust means to protect cellular architecture in dormant cells.


Asunto(s)
Citoplasma/patología , Nutrientes/metabolismo , Inanición/metabolismo , Vacuolas/patología , Autofagia/fisiología , Citoplasma/metabolismo , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae , Schizosaccharomyces , Inanición/patología , Vacuolas/metabolismo
16.
Biochem Biophys Res Commun ; 561: 158-164, 2021 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-34023781

RESUMEN

Remodeling of vacuolar membranes mediated by endosomal sorting complex required for transport (ESCRT) is critical for microautophagy induction in budding yeast. Nutrient depletion and inactivation of target of rapamycin complex 1 (TORC1) protein kinase elicit recruitment of the ESCRT-0 complex (Vps27-Hse1) onto vacuolar membranes and ESCRT-mediated microautophagy induction. Mitotic protein phosphatase Cdc14 antagonizes TORC1-mediated phosphorylation in macroautophagy induction after nutrient starvation and TORC1 inactivation. Here, we report that Cdc14 downregulates microautophagy induction after TORC1 inactivation. Cdc14 dysfunction stimulated the vacuolar membrane recruitment of Hse1, but not Vps27, after TORC1 inactivation, promoting ESCRT-0 complex formation. Conversely, overexpression of CDC14 compromises Hse1 recruitment on vacuolar membranes and microautophagy induction after TORC1 inactivation. Thus, Cdc14 phosphatase regulates the fluxes of two types of autophagy in the opposite directions, namely, it elicits macroautophagy and attenuates microautophagy.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Membranas Intracelulares/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Vacuolas/metabolismo , Membranas Intracelulares/patología , Microautofagia , Monoéster Fosfórico Hidrolasas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Vacuolas/patología
17.
PLoS Pathog ; 15(6): e1007834, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31199856

RESUMEN

V-ATPases are part of the membrane components of pathogen-containing vacuoles, although their function in intracellular infection remains elusive. In addition to organelle acidification, V-ATPases are alternatively implicated in membrane fusion and anti-inflammatory functions controlled by ATP6V0d2, the d subunit variant of the V-ATPase complex. Therefore, we evaluated the role of ATP6V0d2 in the biogenesis of pathogen-containing vacuoles using ATP6V0d2 knock-down macrophages infected with the protozoan parasite Leishmania amazonensis. These parasites survive within IFNγ/LPS-activated inflammatory macrophages, multiplying in large/fusogenic parasitophorous vacuoles (PVs) and inducing ATP6V0d2 upregulation. ATP6V0d2 knock-down decreased macrophage cholesterol levels and inhibited PV enlargement without interfering with parasite multiplication. However, parasites required ATP6V0d2 to resist the influx of oxidized low-density lipoprotein (ox-LDL)-derived cholesterol, which restored PV enlargement in ATP6V0d2 knock-down macrophages by replenishing macrophage cholesterol pools. Thus, we reveal parasite-mediated subversion of host V-ATPase function toward cholesterol retention, which is required for establishing an inflammation-resistant intracellular parasite niche.


Asunto(s)
Colesterol/metabolismo , Regulación Enzimológica de la Expresión Génica , Homeostasis , Leishmania/metabolismo , Macrófagos/metabolismo , Regulación hacia Arriba , ATPasas de Translocación de Protón Vacuolares/biosíntesis , Vacuolas/metabolismo , Animales , Lipoproteínas LDL/metabolismo , Macrófagos/parasitología , Macrófagos/patología , Ratones , Ratones Endogámicos BALB C , Células RAW 264.7 , Vacuolas/parasitología , Vacuolas/patología
18.
Mol Genet Metab ; 134(4): 287-300, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34799272

RESUMEN

Glutaric aciduria type I (GA-I, OMIM # 231670) is an autosomal recessive inborn error of metabolism caused by deficiency of the mitochondrial enzyme glutaryl-CoA dehydrogenase (GCDH). The principal clinical manifestation in GA-I patients is striatal injury most often triggered by catabolic stress. Early diagnosis by newborn screening programs improved survival and reduced striatal damage in GA-I patients. However, the clinical phenotype is still evolving in the aging patient population. Evaluation of long-term outcome in GA-I patients recently identified glomerular filtration rate (GFR) decline with increasing age. We recently created the first knock-in rat model for GA-I harboring the mutation p.R411W (c.1231 C>T), corresponding to the most frequent GCDH human mutation p.R402W. In this study, we evaluated the effect of an acute metabolic stress in form of high lysine diet (HLD) on young Gcdhki/ki rats. We further studied the chronic effect of GCDH deficiency on kidney function in a longitudinal study on a cohort of Gcdhki/ki rats by repetitive 68Ga-EDTA positron emission tomography (PET) renography, biochemical and histological analyses. In young Gcdhki/ki rats exposed to HLD, we observed a GFR decline and biochemical signs of a tubulopathy. Histological analyses revealed lipophilic vacuoles, thinning of apical brush border membranes and increased numbers of mitochondria in proximal tubular (PT) cells. HLD also altered OXPHOS activities and proteome in kidneys of Gcdhki/ki rats. In the longitudinal cohort, we showed a progressive GFR decline in Gcdhki/ki rats starting at young adult age and a decline of renal clearance. Histopathological analyses in aged Gcdhki/ki rats revealed tubular dilatation, protein accumulation in PT cells and mononuclear infiltrations. These observations confirm that GA-I leads to acute and chronic renal damage. This raises questions on indication for follow-up on kidney function in GA-I patients and possible therapeutic interventions to avoid renal damage.


Asunto(s)
Tasa de Filtración Glomerular , Glutaratos/orina , Glutaril-CoA Deshidrogenasa/deficiencia , Riñón/patología , Errores Innatos del Metabolismo/fisiopatología , Animales , Biología Computacional , Modelos Animales de Enfermedad , Femenino , Técnicas de Sustitución del Gen , Humanos , Recién Nacido , Riñón/metabolismo , Masculino , Errores Innatos del Metabolismo/patología , Tamizaje Neonatal , Fosforilación Oxidativa , Mapas de Interacción de Proteínas , Ratas , Vacuolas/patología
19.
Ann Neurol ; 87(3): 480-485, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31925837

RESUMEN

Marked elevation in the brain concentration of N-acetyl-L-aspartate (NAA) is a characteristic feature of Canavan disease, a vacuolar leukodystrophy resulting from deficiency of the oligodendroglial NAA-cleaving enzyme aspartoacylase. We now demonstrate that inhibiting NAA synthesis by intracisternal administration of a locked nucleic acid antisense oligonucleotide to young-adult aspartoacylase-deficient mice reverses their pre-existing ataxia and diminishes cerebellar and thalamic vacuolation and Purkinje cell dendritic atrophy. Ann Neurol 2020;87:480-485.


Asunto(s)
Ácido Aspártico/análogos & derivados , Enfermedad de Canavan/tratamiento farmacológico , Oligonucleótidos Antisentido/uso terapéutico , Acetiltransferasas/antagonistas & inhibidores , Amidohidrolasas/deficiencia , Amidohidrolasas/genética , Animales , Ácido Aspártico/biosíntesis , Ataxia/complicaciones , Ataxia/tratamiento farmacológico , Atrofia/complicaciones , Atrofia/tratamiento farmacológico , Enfermedad de Canavan/complicaciones , Enfermedad de Canavan/patología , Cerebelo/patología , Femenino , Técnicas de Silenciamiento del Gen , Infusiones Intraventriculares , Masculino , Ratones , Mutación , Oligonucleótidos Antisentido/administración & dosificación , Células de Purkinje/patología , Prueba de Desempeño de Rotación con Aceleración Constante , Tálamo/patología , Vacuolas/efectos de los fármacos , Vacuolas/patología
20.
Acta Neuropathol ; 141(3): 341-358, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33492460

RESUMEN

Granulovacuolar degeneration (GVD) is a common feature in Alzheimer's disease (AD). The occurrence of GVD is closely associated with that of neurofibrillary tangles (NFTs) and GVD is even considered to be a pre-NFT stage in the disease process of AD. Currently, the composition of GVD bodies, the mechanisms associated with GVD and how GVD exactly relates to NFTs is not well understood. By combining immunohistochemistry (IHC) and laser microdissection (LMD) we isolated neurons with GVD and those bearing tangles separately from human post-mortem AD hippocampus (n = 12) using their typical markers casein kinase (CK)1δ and phosphorylated tau (AT8). Control neurons were isolated from cognitively healthy cases (n = 12). 3000 neurons per sample were used for proteome analysis by label free LC-MS/MS. In total 2596 proteins were quantified across samples and a significant change in abundance of 115 proteins in GVD and 197 in tangle bearing neurons was observed compared to control neurons. With IHC the presence of PPIA, TOMM34, HSP70, CHMP1A, TPPP and VXN was confirmed in GVD containing neurons. We found multiple proteins localizing specifically to the GVD bodies, with VXN and TOMM34 being the most prominent new protein markers for GVD bodies. In general, protein groups related to protein folding, proteasomal function, the endolysosomal pathway, microtubule and cytoskeletal related function, RNA processing and glycolysis were found to be changed in GVD neurons. In addition to these protein groups, tangle bearing neurons show a decrease in ribosomal proteins, as well as in various proteins related to protein folding. This study, for the first time, provides a comprehensive human based quantitative assessment of protein abundances in GVD and tangle bearing neurons. In line with previous functional data showing that tau pathology induces GVD, our data support the model that GVD is part of a pre-NFT stage representing a phase in which proteostasis and cellular homeostasis is disrupted. Elucidating the molecular mechanisms and cellular processes affected in GVD and its relation to the presence of tau pathology is highly relevant for the identification of new drug targets for therapy.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Degeneración Nerviosa/metabolismo , Ovillos Neurofibrilares/metabolismo , Neuronas/metabolismo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Femenino , Humanos , Cuerpos de Inclusión/metabolismo , Cuerpos de Inclusión/patología , Masculino , Persona de Mediana Edad , Degeneración Nerviosa/patología , Ovillos Neurofibrilares/patología , Neuronas/patología , Proteoma , Vacuolas/metabolismo , Vacuolas/patología
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