ABSTRACT
Biallelic variants in the NARS2 gene are the cause of a continuous spectrum of neurodegenerative disorders presenting with various severity-from spastic paraplegia, progressive neurodegeneration to Leigh and Alpers syndrome. Common clinical signs result from a mitochondrial dysfunction based on OXPHOS deficiency. Here, we present a patient with infantile-onset severe epilepsy leading to fatal refractory status epilepticus. Whole exome sequencing with Exomiser analysis based on HPO terms detected two novel NARS2 variants in a compound heterozygous state. To date, 18 different NARS2 disease-causing mutations have been described. Our study adds to the understanding of this mitochondrial disorder.
Subject(s)
Aspartate-tRNA Ligase/genetics , Mitochondrial Diseases/genetics , Mutation/genetics , Age of Onset , Epilepsy/diagnosis , Epilepsy/genetics , Humans , Infant, NewbornABSTRACT
Recently, biallelic variants in the SORD gene were identified as causal for axonal hereditary neuropathy (HN). We ascertained the spectrum and frequency of SORD variants among a large cohort of Czech patients with unknown cause of HN. Exome sequencing data were analysed for SORD (58 patients). The prevalent c.757del variant was tested with fragment analysis (931 patients). Sanger sequencing in additional 70 patients was done. PCR primers were designed to amplify the SORD gene with the exclusion of the pseudogene SORD2P. Sequence differences between gene and pseudogene were identified and frequencies of SNPs were calculated. Eighteen patients from 16 unrelated families with biallelic variants in the SORD gene were found and the c.757del was present in all patients on at least one allele. Three novel, probably pathogenic, variants were detected, always in a heterozygous state in combination with the c.757del on the second allele. Patients presented with a slowly progressive axonal HN. Almost all patients had moderate pes cavus deformity. SORD neuropathy is frequent in Czech patients and the third most common cause of autosomal recessive HN. The c.757del is highly prevalent. Specific amplification of the SORD gene with the exclusion of the pseudogene is essential for a precise molecular diagnostics.
Subject(s)
Hereditary Sensory and Motor Neuropathy , L-Iditol 2-Dehydrogenase/genetics , Adult , Aged , Cohort Studies , Czech Republic/epidemiology , Female , Hereditary Sensory and Motor Neuropathy/diagnosis , Hereditary Sensory and Motor Neuropathy/epidemiology , Hereditary Sensory and Motor Neuropathy/genetics , Humans , Male , Middle Aged , Mutation , Exome SequencingABSTRACT
BACKGROUND: Primary intracranial sarcoma is a rare disease. Due to the scarcity of evidence from randomized clinical trials, we follow the treatment guidelines of their extracranial counterparts or those published in case reports, while taking into consideration the specificity of radiotherapy within the brain, and the limit imposed on chemotherapy by the blood brain barrier. Nevertheless, surgery remains the golden standard of treatment for primary tumours, and also for recurrence. Even though there are usually narrow margins achieved in brain compared with the extracranial sarcomas. Despite significant effort, prognosis remains dismal. CASE: We present a 69-year old woman who was investigated for psychoorganic syndrome and paresis of the left hand. Magnetic resonance imaging revealed a tumour expansion in her frontal lobe with collateral oedema. Surgical resection was indicated. Histology of the specimen suggested a myxoid meningeal sarcoma. Early disease recurrence 4 months after primary resection was treated by reresection and 50 Gy of adjuvant radiotherapy to the tumour bed. Similarly, another recurrence 19 months after the second surgery was treated using the same approach. Systemic treatment has not been indicated so far. At this time, the patient is without evidence of any disease recurrence and continues with regular follow-up. CONCLUSION: Myxoid meningeal sarcoma represents a rare disease with a high risk of recurrence. Unfortunately, there is no clear recommendation for treatment algorithm. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.
Subject(s)
Meningeal Neoplasms/radiotherapy , Meningeal Neoplasms/surgery , Sarcoma/radiotherapy , Sarcoma/surgery , Aged , Female , Humans , Magnetic Resonance Imaging , Meningeal Neoplasms/diagnostic imaging , Meningeal Neoplasms/pathology , Neoplasm Recurrence, Local , Sarcoma/diagnostic imaging , Sarcoma/pathologyABSTRACT
The objectives of this study were to evaluate patients with aortic abdominal aneurysm (AAA) with regard to immunoglobulin (Ig)G4-related disease (IgG4-RD). IgG4-RD represents a recently defined condition comprised of a collection of disorders characterized by IgG4 hypergammaglobulinemia, the presence of IgG4-positive plasma cells in organs affected with fibrotic or sclerotizing changes and typical histopathological features. It was identified as a possible cause of vasculitis in large vessels. Studies have been published on a possible association between inflammatory aortic or cardiovascular disease and IgG4-RD. We examined 114 patients with AAA requiring surgery in order to identify findings which are characteristic of IgG4-RD. Aneurysm samples from seven patients showed histopathological features consistent with IgG4-RD and the presence of IgG4+ plasma cells. Only two of these seven patients showed elevated IgG4 serum levels higher 1·35 g/l. In five of the patients, the concentration of serum IgG4 was lower than 1·20 g/l, with the number of IgG4+ plasma cells being higher than 50/high-power field. These findings were consistent with AAA being a heterogeneous group of inflammatory diseases with different pathogenesis.
Subject(s)
Aortic Aneurysm, Abdominal/immunology , Hypergammaglobulinemia/immunology , Immunoglobulin G4-Related Disease/immunology , Immunoglobulin G/immunology , Plasma Cells/immunology , Aged , Aorta/immunology , Aorta/metabolism , Aorta/pathology , Aortic Aneurysm, Abdominal/blood , Aortic Aneurysm, Abdominal/pathology , Female , Humans , Hypergammaglobulinemia/blood , Hypergammaglobulinemia/pathology , Immunoglobulin G/blood , Immunoglobulin G4-Related Disease/blood , Immunoglobulin G4-Related Disease/pathology , Male , Middle Aged , Plasma Cells/metabolism , Plasma Cells/pathology , Retrospective StudiesABSTRACT
Biallelic SBF2 mutations cause Charcot-Marie-Tooth disease type 4B2 (CMT4B2), a sensorimotor neuropathy with autosomal recessive inheritance and association with glaucoma. Since the discovery of the gene mutation, only few additional patients have been reported. We identified seven CMT4B2 families with nine different SBF2 mutations. Revisiting genetic and clinical data from our cohort and the literature, SBF2 variants were private mutations, including exon-deletion and de novo variants. The neuropathy typically started in the first decade after normal early motor development, was predominantly motor and had a rather moderate course. Electrophysiology and nerve biopsies indicated demyelination and excess myelin outfoldings constituted a characteristic feature. While neuropathy was >90% penetrant at age 10 years, glaucoma was absent in ~40% of cases but sometimes developed with age. Consequently, SBF2 mutation analysis should not be restricted to individuals with coincident neuropathy and glaucoma, and CMT4B2 patients without glaucoma should be followed for increased intraocular pressure. The presence of exon-deletion and de novo mutations demands comprehensive mutation scanning and family studies to ensure appropriate diagnostic approaches and genetic counseling.
Subject(s)
Charcot-Marie-Tooth Disease/diagnosis , Charcot-Marie-Tooth Disease/genetics , Genetic Association Studies , Genetic Predisposition to Disease , Mutation , Phenotype , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Adolescent , Adult , Biopsy , Child , Female , Genetic Association Studies/methods , Humans , Male , Young AdultABSTRACT
The strongest and best-documented risk factor for drug hypersensitivity (DH) is the history of a previous reaction. Accidental exposures to drugs may lead to severe or even fatal reactions in sensitized patients. Preventable prescription errors are common. They are often due to inadequate medical history or poor risk assessment of recurrence of drug reaction. Proper documentation is essential information for the doctor to make sound therapeutic decision. The European Network on Drug Allergy and Drug Allergy Interest Group of the European Academy of Allergy and Clinical Immunology have formed a task force and developed a drug allergy passport as well as general guidelines of drug allergy documentation. A drug allergy passport, a drug allergy alert card, a certificate, and a discharge letter after medical evaluation are adequate means to document DH in a patient. They are to be handed to the patient who is advised to carry the documentation at all times especially when away from home. A drug allergy passport should at least contain information on the culprit drug(s) including international nonproprietary name, clinical manifestations including severity, diagnostic measures, potential cross-reactivity, alternative drugs to prescribe, and where more detailed information can be obtained from the issuer. It should be given to patients only after full allergy workup. In the future, electronic prescription systems with alert functions will become more common and should include the same information as in paper-based documentation.
Subject(s)
Documentation , Drug Hypersensitivity/diagnosis , Health Smart Cards , Documentation/methods , Drug Hypersensitivity/etiology , Drug Hypersensitivity/prevention & control , Europe , Humans , Surveys and QuestionnairesABSTRACT
UNLABELLED: Determination of mTREM-1 expression on monocytes has been investigated as a perspective diagnostic method to distinguish infectious from non-infectious etiology of the inflammation. THE AIMS OF OUR STUDY WERE: i) to investigate the expression of TREM-1 on monocytes in septic patients and in those after elective spinal surgery without infection; ii) to assess the dynamics of mTREM-1 expression on monocytes and its association with the outcome in patients with severe sepsis. Fifty two patients with severe sepsis, 20 healthy volunteers, and 20 patients after elective spinal surgery were involved in our study. TREM-1 expression on monocytes was evaluated by flow cytometry. Compared with the group of healthy adults (median 42.0, interquartile range (IQR) 30.3-76 MFI), mTREM-1 expression was increased in the group of septic patients both at entry (median 138.4, IQR 78.4-187.5 MFI) and the last examination (median 136.5, IQR 69.0-170.0 MFI) as well as in patients 24 hours after spinal surgery (median 138.5, IQR 45.3-165.5 MFI). The increase was statistically significant. mTREM-1 expression in patients undergoing spinal surgery and those with severe sepsis did not differ. TREM-1 expression on the monocytes in survivors was higher than in non-survivors (p=0.007). TREM-1 levels in septic non-surviving patients correlated weakly with TNF-α levels (r=0.38; p=0.003) and with HLA-DR/CD14 levels (r=0.38; p=0.003). Increased TREM-1 expression on monocytes is not associated exclusively with the presence of systemic infection.
Subject(s)
Membrane Glycoproteins/metabolism , Monocytes/metabolism , Receptors, Immunologic/metabolism , Systemic Inflammatory Response Syndrome/metabolism , Adult , Female , HLA-DR Antigens/metabolism , Humans , Male , Middle Aged , Spine/surgery , Triggering Receptor Expressed on Myeloid Cells-1 , Young AdultABSTRACT
OBJECTIVE: Heat shock proteins (Hsps) have been repeatedly implicated in the pathogenesis of rheumatoid arthritis (RA). The aim of this work was to study Hsp mRNA and protein levels to determine whether they can be used to differentiate between RA, osteoarthritis (OA), and healthy controls. METHODS: Hsp27, Hsp60, Hsp70, Hsp90α, and HspBP1 mRNA expression was analysed using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) in 24 RA, 11 OA, and 21 healthy controls. Hsp70 and HspBP1 protein levels were measured in serum using an enzyme-linked immunosorbent assay (ELISA). RESULTS: Hsp gene expression profiles differ significantly between inflammatory (RA) and non-inflammatory (OA) joint diseases, showing significantly increased Hsp27 and Hsp90α mRNA levels in RA synovial tissues. Up-regulated Hsp60 and Hsp90α together with down-regulated Hsp70 and elevated HspBP1/Hsp70 mRNA ratios can be used to differentiate between RA patients and healthy individuals through analysis of peripheral blood samples. Despite increased HspBP1 levels in RA sera, Hsp70 levels and the HspBP1/Hsp70 protein ratio remained identical in the RA patients and healthy individuals, which may contribute to the inhibition of Hsp70 anti-apoptotic activity. CONCLUSION: Hsp gene expression analysis can be implemented as a new diagnostic approach to facilitate differentiation between RA, OA, and healthy controls.
Subject(s)
Arthritis, Rheumatoid/diagnosis , Gene Expression Profiling , Heat-Shock Proteins/genetics , Osteoarthritis/diagnosis , Aged , Arthritis, Rheumatoid/genetics , Cohort Studies , Diagnosis, Differential , Down-Regulation , Female , Humans , Male , Middle Aged , Osteoarthritis/genetics , Synovial Membrane/metabolism , Up-RegulationABSTRACT
Ormond disease - idiopathic retroperitoneal fibrosis - is a rare condition characterized in situ by the development of fibrous plaques in the retroperitoneal space and anatomicaly dependent structures. The associated encasement of both ureters and progress to hydronefrosis of the kidney are typical clinical manifestations. Less typical manifestations are possible (for example chronic periaortitis), where clinical diagnosis is more difficult. The laboratory findings are not specific for this disease and a biopsy is not always possible for anatomical reasons. In these cases, the use of positron emission tomography/computed tomography - has been found to be the solution, specifically for patients with periaortitis. Ormond disease is generally idiopathic, and secondary - to the use of certain drugs, malignant diseases, infections. Idiopathic retroperitoneal disease is thought to result from the clinical manifestation of a systemic autoimmune disease. The purpose of this article is to present two casuistics, one of a less than usual clinical manifestation. Both positron emission tomography/computed tomography were used in the diagnostics. The treatment ofOrmond disease involves the combination of surgical and immunosuppressive treatment.
Subject(s)
Retroperitoneal Fibrosis , Adult , Female , Humans , Male , Positron-Emission Tomography , Retroperitoneal Fibrosis/complications , Retroperitoneal Fibrosis/diagnosis , Tomography, X-Ray ComputedABSTRACT
BACKGROUND: Sequence homology and cross reactivity between microbial and human heat shock proteins (hsps) led to the concept that hsps might be involved in the etiopathogenesis of autoimmune diseases. OBJECTIVE: In our study we stimulated peripheral blood mononuclear cells (PBMC) of patients with juvenile idiopathic arthritis (JIA) and healthy controls with various hsp-derived peptides together with the whole molecules of corresponding hsp. METHODS: PBMC were cultured with recombinant human hsp60 (rh-hsp60), rh-hsp70, Mycobacterium bovis hsp65 (M.bovis hsp65), P562-571 human hsp60, P180-188 M. bovis hsp65, P450-463 human hsp70 and P545-554 cytokeratin derived synthetic peptides. Cell responses were measured after incorporation of (3)H-thymidine and expressed as stimulation indices. RESULTS AND CONCLUSION: We found elevated proliferative response to rh-hsp60, M. bovis hsp65 and P562-571 human hsp60 derived peptide in patients with JIA polyarthritis. Significantly elevated proliferation to P180-188 M. bovis hsp65 was found in JIA lasting more than 2 years. None of the particular clinical characteristics (RF, ANA, HLA B27 and disease activity) seemed to be associated with hsp or hsp-derived synthetic peptide proliferative response in the JIA cohort.
Subject(s)
Arthritis, Juvenile/pathology , Heat-Shock Proteins/chemistry , Heat-Shock Proteins/pharmacology , Leukocytes, Mononuclear/drug effects , Peptide Fragments/chemical synthesis , Peptide Fragments/pharmacology , Adolescent , Adult , Cell Proliferation/drug effects , Cells, Cultured , Child , Female , Heat-Shock Proteins/metabolism , Humans , Male , Mycobacterium bovis/metabolism , Peptide Fragments/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Recombinant Proteins/pharmacologyABSTRACT
BACKGROUND: Sepsis is a serious disease with a high case fatality rate. A variety of changes in the host immune responsiveness are observed in the pathogenesis of sepsis, ranging from detrimental hyperinflammation to profound immunoparalysis, i.e. acquired immunodeficiency. The level of monocyte HLA-DR expression reflects the functional status of monocytes as antigen-presenting cells and granulocyte CD64 expression is also indicative of infectious inflammation. MATERIAL AND METHODS: Monocyte HLA-DR expression and granulocyte CD64 expression were measured in 49 septic patients and 30 healthy controls using flow cytometry focused on three parameters: positive cell percentage, mean fluorescence intensity and quantitation of antibodies bound per cell (QuantiBRITE). RESULTS: The significance of both monocyte HLA-DR expression and granulocyte CD64 expression in septic patients was confirmed. Monocyte HLA-DR dramatically decreases in septic patients compared to controls, is one of the prognostic factors and correlates with C-reactive protein. In contrast, granulocyte CD64 sharply rises in patients with sepsis and correlates with mediators of systemic inflammation (procalcitonin - PCT), proinflammatory mediators (interleukin-6 - IL-6, lipopolysaccharide binding protein - LBP) and anti-inflammatory cytokines (interleukin-10 - IL10). CONCLUSION: Quantitative monocyte HLA-DR expression and granulocyte CD64 expression are useful indicators in septic patients when considered along with the panel of other markers, monitored over a period of time and in the context of the clinical course of sepsis.
Subject(s)
Flow Cytometry , Granulocytes/immunology , HLA-DR Antigens/analysis , Monocytes/immunology , Receptors, IgG/analysis , Sepsis/immunology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle AgedABSTRACT
OBJECTIVE: Enrichment of nucleated red blood cells (NRBCs) from maternal blood for non-invasive prenatal diagnosis. DESIGN: Pilot study. SETTING: 2nd Clinic of Paediatrics, University Hospital Motol, Prague, Czech Republic. METHODS: Mononuclear cells were isolated from 13-28 ml of peripheral maternal blood between 13 and 37 weeks of gestation. Leukocytes from maternal peripheral blood were depleted from mononuclear cells by treatment with anti-CD14 and anti-CD45 microbeads and high-gradient magnetic cell separation (MACS) on VarioMACS. NRBCs were sorted from CD14-/CD45- fraction by positive selection using anti-CD71 microbeads on MiniMACS. All sorting steps were analysed by three-colour cytometric analysis with FACScan flow cytometer. RESULTS: In 68 out of 78 pregnant woman (87%) NRBCs were found in range 2 x 10(5) - 1.02 x 10(6). NRBC were enriched with an average enrichment rate of 138-fold ranging from 4-526 fold. In our cohort of pregnant woman the number of isolated NRBCs was individual. We identified NRBCs from the 13th week of gestation. CONCLUSION: The aim of the study is to establish and standardise the method of enrichment of NRBCs from maternal blood samples and verify the applicability of this alternative source for non-invasive prenatal diagnosis.
Subject(s)
Erythroblasts , Erythrocyte Count , Fetal Blood/cytology , Prenatal Diagnosis , Antigens, CD/analysis , Antigens, Differentiation, B-Lymphocyte/analysis , Erythroblasts/immunology , Female , Humans , Leukocyte Common Antigens/analysis , Lipopolysaccharide Receptors/analysis , Pregnancy , Pregnancy Trimesters , Receptors, TransferrinABSTRACT
Bronchopulmonary dysplasia is a chronic pneumopathy of preterm infants, with significant associated mortality and morbidity, for which there is no effective preventive therapy. Pulmonary O2 toxicity is thought to be a major contributor to the development of bronchopulmonary dysplasia, and antioxidant interventions hold significant promise for therapy. The relative importance of specific reactive oxygen species in the development of O2-mediated lung injury is unknown. In this study, we tested the effect of a synthetic 21-aminosteroid, U74389G, on 95% O2-induced free radical production, lipid peroxidation, and inhibition of postnatal lung growth in a neonatal rat model. Lipid peroxidation products, as measured by total 8-isoprostane and aldehydes, and hydroxyl radical formation, assessed using salicylate metabolites, in rat lungs and serum were significantly increased after exposure to 95% O2. These changes could be completely or partially attenuated by U74389G. However, U74389G did not improve the survival rate or lung wet-to-dry weight ratio. Expression of proliferating cell nuclear antigen, a marker for DNA synthesis, was examined by immunohistochemistry. Four- or 7-d-old control rat lungs had active DNA synthesis, which was inhibited by exposure to 95% O2. U74389G had a protective effect against 95% O2-mediated inhibition of DNA synthesis. Air-exposed animals treated with U74389G had a modest reduction in lung DNA synthesis, consistent with a role for hydroxyl radicals or lipid hydroperoxides as second messengers in the normal regulation of lung growth.
Subject(s)
Antioxidants/pharmacology , Lipid Peroxidation/drug effects , Lung/drug effects , Lung/metabolism , Oxygen/metabolism , Pregnatrienes/pharmacology , Animals , Animals, Newborn , Bronchopulmonary Dysplasia/metabolism , Bronchopulmonary Dysplasia/prevention & control , Free Radicals/metabolism , Humans , Infant, Newborn , Lung/growth & development , Oxygen/pharmacology , Rats , Rats, Sprague-DawleyABSTRACT
Glypicans are a family of heparan sulfate proteoglycans that are linked to the cell surface through a glycosyl-phosphatidylinositol anchor. One member of this family, glypican-3 (Gpc3), is mutated in patients with the Simpson-Golabi-Behmel syndrome (SGBS). These patients display pre- and postnatal overgrowth, and a varying range of dysmorphisms. The clinical features of SGBS are very similar to the more extensively studied Beckwith-Wiedemann syndrome (BWS). Since BWS has been associated with biallelic expression of insulin-like growth factor II (IGF-II), it has been proposed that GPC3 is a negative regulator of IGF-II. However, there is still no biochemical evidence indicating that GPC3 plays such a role.Here, we report that GPC3-deficient mice exhibit several of the clinical features observed in SGBS patients, including developmental overgrowth, perinatal death, cystic and dyplastic kidneys, and abnormal lung development. A proportion of the mutant mice also display mandibular hypoplasia and an imperforate vagina. In the particular case of the kidney, we demonstrate that there is an early and persistent developmental abnormality of the ureteric bud/collecting system due to increased proliferation of cells in this tissue element. The degree of developmental overgrowth of the GPC3-deficient mice is similar to that of mice deficient in IGF receptor type 2 (IGF2R), a well characterized negative regulator of IGF-II. Unlike the IGF2R-deficient mice, however, the levels of IGF-II in GPC3 knockouts are similar to those of the normal littermates.
Subject(s)
Abnormalities, Multiple/genetics , Growth Disorders/genetics , Heparan Sulfate Proteoglycans , Heparitin Sulfate/deficiency , Insulin-Like Growth Factor II/analysis , Proteoglycans/deficiency , Abnormalities, Multiple/physiopathology , Animals , Beckwith-Wiedemann Syndrome/genetics , Beckwith-Wiedemann Syndrome/physiopathology , Body Weight , Cell Division , Female , Genotype , Glypicans , Growth Disorders/physiopathology , Heparitin Sulfate/genetics , Heparitin Sulfate/physiology , Humans , Insulin-Like Growth Factor II/genetics , Kidney Tubules, Collecting/abnormalities , Kidney Tubules, Collecting/embryology , Kidney Tubules, Collecting/pathology , Male , Mandible/abnormalities , Mandible/embryology , Mice , Mice, Inbred C57BL , Mice, Knockout , Organ Size , Phenotype , Proteoglycans/genetics , Proteoglycans/physiology , SyndromeABSTRACT
It is unknown which of the reactive oxygen species is primarily responsible for the cytotoxicity of 95% O2 for rat distal fetal lung epithelial cells in vitro. Incubation of cells with 25 U/ml polyethylene glycol (PEG)-conjugated SOD and 50 U/ml PEG-catalase, but not PEG-SOD or SOD mimics alone, significantly reduced 95% O2-mediated cytotoxicity. Liposome-entrapped catalase, without SOD, also significantly reduced 95% O2-mediated cytotoxicity. Increased formation of lipid hydroperoxides, as assessed by the formation of 8-isoprostane and aldehydes, was attenuated by both 100 microM Trolox, a vitamin E analogue, and by 5 microM U74389G, an amino steroid. Trolox, but not U74389G, prevented an increase in cell-derived H2O2, hydroxyl radical and 95% O2-mediated cytotoxicity. An increase in hydroxyl radical formation, but not cell death, observed in 95% O2, was prevented by 0.1 microM phenanthrolene, a cell permeant iron chelator. DNA extracts of rat distal fetal lung epithelial cells maintained under serum-free conditions had an electrophoretic pattern consistent with some degree of apoptosis. However, no increase in laddering was seen with exposure to 95% O2. These data are consistent with hydrogen peroxide, but not lipid hydroperoxides or hydroxyl radical, being a critical effector of O2-mediated necrotic cell death in distal lung epithelial cells.
Subject(s)
Epithelial Cells/drug effects , Hydrogen Peroxide/toxicity , Lung/drug effects , Oxygen/toxicity , Analysis of Variance , Animals , Antioxidants/metabolism , Apoptosis/drug effects , Catalase/metabolism , Cells, Cultured , Lung/embryology , Lung/pathology , Necrosis , Rats , Rats, Wistar , Superoxides/metabolismABSTRACT
Cationic liposomes, 1:1 (mol/mol) 1,2-dioleoyldimethylammonium chloride-1,2-dioleoyl-sn-glycero-3-phosphoethanolamine, were used to transfect primary cultures of distal rat fetal lung epithelial cells with pCMV4-based plasmids. A DNA-to-lipid ratio of 1:10 to 1:15 (wt/wt) optimized DNA uptake over a 24-h exposure. At a fixed DNA-to-lipid ratio of 1:15, chloramphenicol acetyltransferase (CAT) reporter gene expression declined at lipid concentrations > 2.5 nmol/cm2 cell surface area, whereas DNA uptake remained concentration dependent. CAT expression peaked 48 h after removal of the liposome-DNA complex, declining thereafter. Reporter gene expression was increased, and supercoiled cDNA degradation was reduced by the addition of 0.2 mM nicotinamide and 10 microM chloroquine. Rat fetal lung epithelial cells transfected with two different expression cassettes had an increased susceptibility to superoxide-mediated cytotoxicity. This could be attributed to a nonspecific delivery of exogenous DNA or some other copurified factor. The DNA-dependent increase in superoxide-mediated cytotoxicity, but not basal levels of cytotoxicity, was inhibited by the addition of 0.2 mM nicotinamide and 10 microM chloroquine.
Subject(s)
Chloramphenicol O-Acetyltransferase/genetics , DNA/metabolism , Epithelial Cells/physiology , Lung/physiology , Transfection/methods , Animals , Cell Survival/drug effects , Cells, Cultured , Chloramphenicol O-Acetyltransferase/biosynthesis , Cytomegalovirus , Drug Carriers , Epithelial Cells/cytology , Epithelial Cells/drug effects , Fetus , Genes, Reporter , Genetic Vectors , Liposomes , Lung/cytology , Lung/drug effects , Phosphatidylethanolamines , Plasmids , Quaternary Ammonium Compounds , Rats , Recombinant Proteins/biosynthesis , Superoxides/toxicityABSTRACT
Glucocorticoids have been shown to accelerate fetal lung type II cell maturation, and this effect appears, in part, to be mediated via fibroblasts. To identify glucocorticoid induced genes in fetal lung fibroblasts, we screened a cDNA library from cortisol-treated fetal lung fibroblasts with a subtracted cDNA probe which was enriched for sequences specific for cortisol-treated fetal lung fibroblasts. Fifty-seven clones were isolated from the cDNA library. One cDNA represented approximately 30% of the 57 clones. Analysis of DNA sequence homology suggested that this cDNA encodes the rat transforming growth factor-beta 3 (TGF beta 3). We found that TGF beta 3 mRNA was expressed in fetal lung fibroblasts but not epithelial cells. Expression of message in fetal lung fibroblasts was developmentally regulated. TGF beta 3 mRNA levels were low during the pseudoglandular stage (day 18), peaked during the early canalicular stage of lung development (day 19), then fell again at days 20 and 21 (term = 22 days). Exposure of fetal lung fibroblasts to cortisol increased TGF beta 3 mRNA expression in a time- and dose-dependent manner. Maternal administration of dexamethasone also enhanced mRNA expression of TGF beta 3 in fetal lung fibroblasts. These data suggest that glucocorticoids may mediate their stimulatory effect on lung maturation by inducing TGF beta 3 expression in fetal lung fibroblasts.
Subject(s)
Gene Expression Regulation, Developmental , Glucocorticoids/physiology , Lung/metabolism , Transforming Growth Factor beta/genetics , Amino Acid Sequence , Animals , Base Sequence , Cell Differentiation/genetics , Cell Division/genetics , Cloning, Molecular , DNA, Complementary , Female , Fibroblasts/metabolism , Lung/cytology , Lung/embryology , Male , Molecular Sequence Data , Rats , Rats, WistarABSTRACT
There is increasing evidence to suggest that platelet-derived growth factor (PDGF) or PDGF-like molecules play a role in fetal lung morphogenesis. Our previous studies demonstrated the presence of PDGF-AA and PDGF-BB homodimers in embryonic and fetal rat lung. To explore further the role for PDGF-BB in embryonic lung development, we conducted intervention studies using PDGF-B chain-specific antisense oligodeoxynucleotides in a simple embryonic rat lung explant system. Unmodified antisense PDGF-B oligodeoxynucleotides inhibited, in a concentration-dependent manner, DNA synthesis of embryonic lung. A maximal inhibition of 50% was observed. The inhibitory effect of antisense PDGF-B oligodeoxynucleotides on DNA synthesis was reversed by the addition of exogenous PDGF-BB but not PDGF-AA. Antisense treatment decreased PDGF-BB but not PDGF-AA protein content, as assessed by immunoblot analyses. Incubation of lung explants with PDGF-BB neutralizing antibodies also resulted in an inhibition of DNA synthesis. Morphometric analyses of antisense-treated cultures showed a significant reduction in lung size when compared to control cultures. The epithelial component of the embryonic lungs was specifically reduced, both in mass and DNA labelling index, by antisense treatment. The number of terminal buds of the lung explants was not significantly affected by antisense PDGF-B treatment. Scrambled PDGF-B oligodeoxynucleotides had no effect. These data suggest that PDGF-BB is involved in regulating growth, but not the degree of branching, of embryonic rat lung.