RESUMO
Although mucopolysaccharidoses (MPS) are monogenic diseases, caused by mutations in genes coding for enzymes involved in degradation of glycosaminoglycans (GAGs), recent studies suggested that changes in expressions of various genes might cause secondary and tertiary cellular dysfunctions modulating the course of these diseases. In this report, we demonstrate that vesicle trafficking regulation is affected in fibroblasts derived from patients suffering from 11 different types of MPS due to changes in levels of crucial proteins (estimated by automated Western-blotting) involved in this process, including caveolin, clathrin, huntingtin (Htt), APPL1, EEA1, GOPC, Rab5, and Rab7. Microscopic studies confirmed these results, while investigations of tissue samples derived from the MPS I mouse model indicated differences between various organs in this matter. Moreover, transcriptomic analyses provided a global picture for changes in expressions of genes related to vesicle trafficking in MPS cells. We conclude that vesicle trafficking is dysregulated in MPS cells and changes in this process might contribute to the molecular mechanisms of this disease. Most probably, primary GAG storage might cause a cellular stress response leading to dysregulation of expression of many genes which, in turn, results in changes in cellular processes like vesicle trafficking. This can significantly modulate the course of the disease due to enhancing accumulation of GAGs and altering crucial cellular processes. This hypothesis has been supported by normalization of levels of clathrin in MPS cells treated with either an active form of the deficient GAG-degrading enzyme or a compound (5,7-dihydroxy-3-(4-hydroxyphenyl)-4H-1-benzopyran-4-one) indirectly reducing the efficiency of GAG synthesis.
Assuntos
Mucopolissacaridoses , Camundongos , Animais , Linhagem Celular , Mucopolissacaridoses/genética , Mucopolissacaridoses/tratamento farmacológico , Mucopolissacaridoses/metabolismo , Glicosaminoglicanos/metabolismo , Proteínas da Matriz do Complexo de Golgi/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismoRESUMO
The methylotrophic yeast Komagataella phaffii is considered one of the most effective producers of recombinant proteins of industrial importance. Effective producers should be characterized by the maximal reduction of degradation of the cytosolic recombinant proteins. The mechanisms of degradation of cytosolic proteins in K. phaffii have not been elucidated; however, data suggest that they are partially degraded in the autophagic pathway. To identify factors that influence this process, a developed system for the selection of recombinant strains of K. phaffii with impaired autophagic degradation of the heterologous model cytosolic protein (yeast ß-galactosidase) was used for insertional tagging of the genes involved in cytosolic proteins degradation. In one of the obtained strains, the insertion cassette disrupted the open reading frame of the gene encoding ß-1,6-N-acetylglucosaminyltransferase. A recombinant strain with deletion of this gene was also obtained. The rate of degradation of the ß-galactosidase enzyme was two times slower in the insertion mutant and 1.5 times slower in the deletion strain as compared to the parental strain with native ß-1,6-N-acetylglucosaminyltransferase. The rate of degradation of native K. phaffii cytosolic and peroxisomal enzymes, formaldehyde dehydrogenase, formate dehydrogenase, and alcohol oxidase, respectively, showed similar trends to that of ß-galactosidase-slower degradation in the deletion and insertional mutants as compared to the wild-type strain, but faster protein degradation relative to the strain completely defective in autophagy. We conclude that K. phaffii gene designated ACG1, encoding ß-1,6-N-acetylglucosaminyltransferase, is involved in autophagy of the cytosolic and peroxisomal proteins.
Assuntos
N-Acetilglucosaminiltransferases , Saccharomycetales , Saccharomycetales/genética , Proteínas Recombinantes/metabolismo , beta-Galactosidase , Autofagia/genéticaRESUMO
Neurodegenerative diseases represent a large group of disorders characterized by gradual loss of neurons and functions of the central nervous systems. Their course is usually severe, leading to high morbidity and subsequent inability of patients to independent functioning. Vast majority of neurodegenerative diseases is currently untreatable, and only some symptomatic drugs are available which efficacy is usually very limited. To develop novel therapies for this group of diseases, it is crucial to understand their pathogenesis and to recognize factors which can influence the disease course. One of cellular structures which dysfunction appears to be relatively poorly understood in the light of neurodegenerative diseases is tubulin cytoskeleton. On the other hand, its changes, both structural and functional, can considerably influence cell physiology, leading to pathological processes occurring also in neurons. In this review, we summarize and discuss dysfunctions of tubulin cytoskeleton in various neurodegenerative diseases different than primary tubulinopathies (caused by mutations in genes encoding the components of the tubulin cytoskeleton), especially Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, prion diseases, and neuronopathic mucopolysaccharidoses. It is also proposed that correction of these disorders might attenuate the progress of specific diseases, thus, finding newly recognized molecular targets for potential drugs might become possible.
Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Tubulina (Proteína)/uso terapêutico , Citoesqueleto/patologia , Microtúbulos , Doença de Alzheimer/genéticaRESUMO
Until now, only a few studies have focused on the early onset of symptoms of alkaptonuria (AKU) in the pediatric population. This prospective, longitudinal study is a comprehensive approach to the assessment of children with recognized AKU during childhood. The study includes data from 32 visits of 13 patients (five males, eight females; age 4-17 years) with AKU. A clinical evaluation was performed with particular attention to eye, ear, and skin pigmentation, musculoskeletal complaints, magnetic resonance imaging (MRI), and ultrasound (US) imaging abnormalities. The cognitive functioning and adaptive abilities were examined. Molecular genetic analyses were performed. The most common symptoms observed were dark urine (13/13), followed by joint pain (6/13), and dark ear wax (6/13). In 4 of 13 patients the values obtained in the KOOS-child questionnaire were below the reference values. MRI and US did not show degenerative changes in knee cartilages. One child had nephrolithiasis. Almost half of the children with AKU (5/13) presented deficits in cognitive functioning and/or adaptive abilities. The most frequent HGD variants observed in the patients were c.481G>A (p.Gly161Arg) mutation and the c.240A>T (p.His80Gln) polymorphism. The newly described allele of the HGD gene (c.948G>T, p.Val316Phe) which is potentially pathogenic was identified.
Assuntos
Alcaptonúria , Criança , Masculino , Feminino , Humanos , Pré-Escolar , Adolescente , Alcaptonúria/diagnóstico , Alcaptonúria/genética , Alcaptonúria/patologia , Homogentisato 1,2-Dioxigenase/genética , Estudos Prospectivos , Estudos Longitudinais , MutaçãoRESUMO
Development of molecular biology and understanding structures and functions of various biological molecules and entities allowed to construct various sophisticated tools for different biotechnological, medical, and veterinary applications. One of them is the phage display technology, based on the possibility to create specific bacteriophages bearing fusion genes, which code for fusion proteins consisting of a phage coat protein and a peptide of any amino acid sequence. Such proteins retain their biological functions as structural elements of phage virions while exposing foreign peptide sequences on their surfaces. Genetic manipulations allow to construct phage display libraries composed of billions of variants of exposed peptides; such libraries can be used to select peptides of desired features. Although the phage display technology has been widely used in biotechnology and medicine, its applications in veterinary and especially in poultry science were significantly less frequent. Nevertheless, many interesting discoveries have been reported also in the latter field, providing evidence for a possibility of effective applications of phage display-related methods in developing novel diagnostic tools, new vaccines, and innovative potential therapies dedicated to poultry. Especially, infectious diseases caused by avian viruses, bacteria, and unicellular eukaryotic parasites were investigated in this field. These studies are summarized and discussed in this review, with presentation of various possibilities provided by different phage display systems in development of useful and effective products facilitating management of the problem of infectious diseases of poultry.
Assuntos
Bacteriófagos , Doenças Transmissíveis , Animais , Humanos , Biblioteca de Peptídeos , Aves Domésticas , Peptídeos/química , Bacteriófagos/genética , Bacteriófagos/metabolismoRESUMO
The oxytocin receptor (OXTR), encoded by the OXTR gene, is responsible for the signal transduction after binding its ligand, oxytocin. Although this signaling is primarily involved in controlling maternal behavior, it was demonstrated that OXTR also plays a role in the development of the nervous system. Therefore, it is not a surprise that both the ligand and the receptor are involved in the modulation of behaviors, especially those related to sexual, social, and stress-induced activities. As in the case of every regulatory system, any disturbances in the structures or functions of oxytocin and OXTR may lead to the development or modulation of various diseases related to the regulated functions, which in this case include either mental problems (autism, depression, schizophrenia, obsessive-compulsive disorders) or those related to the functioning of reproductive organs (endometriosis, uterine adenomyosis, premature birth). Nevertheless, OXTR abnormalities are also connected to other diseases, including cancer, cardiac disorders, osteoporosis, and obesity. Recent reports indicated that the changes in the levels of OXTR and the formation of its aggregates may influence the course of some inherited metabolic diseases, such as mucopolysaccharidoses. In this review, the involvement of OXTR dysfunctions and OXTR polymorphisms in the development of different diseases is summarized and discussed. The analysis of published results led us to suggest that changes in OXTR expression and OXTR abundance and activity are not specific to individual diseases, but rather they influence processes (mostly related to behavioral changes) that might modulate the course of various disorders. Moreover, a possible explanation of the discrepancies in the published results of effects of the OXTR gene polymorphisms and methylation on different diseases is proposed.
Assuntos
Doença , Ocitocina , Receptores de Ocitocina , Feminino , Humanos , Gravidez , Metilação de DNA , Ligantes , Comportamento Materno , Ocitocina/metabolismo , Receptores de Ocitocina/metabolismoRESUMO
Mucopolysaccharidoses (MPS) are a group of diseases caused by mutations resulting in deficiencies of lysosomal enzymes which lead to the accumulation of partially undegraded glycosaminoglycans (GAG). This phenomenon causes severe and chronic disturbances in the functioning of the organism, and leads to premature death. The metabolic defects affect also functions of the brain in most MPS types (except types IV, VI, and IX). The variety of symptoms, as well as the ineffectiveness of GAG-lowering therapies, question the early theory that GAG storage is the only cause of these diseases. As disorders of ion homeostasis increasingly turn out to be co-causes of the pathogenesis of various human diseases, the aim of this work was to determine the perturbations related to the maintenance of the ion balance at both the transcriptome and cellular levels in MPS. Transcriptomic studies, performed with fibroblasts derived from patients with all types/subtypes of MPS, showed extensive changes in the expression of genes involved in processes related to ion binding, transport and homeostasis. Detailed analysis of these data indicated specific changes in the expression of genes coding for proteins participating in the metabolism of Ca2+, Fe2+ and Zn2+. The results of tests carried out with the mouse MPS I model (Idua-/-) showed reductions in concentrations of these 3 ions in the liver and spleen. The results of these studies indicate for the first time ionic concentration disorders as possible factors influencing the course of MPS and show them as hypothetical, additional therapeutic targets for this rare disease.
Assuntos
Mucopolissacaridoses , Mucopolissacaridose I , Animais , Linhagem Celular , Glicosaminoglicanos/metabolismo , Homeostase , Humanos , Camundongos , Mucopolissacaridoses/metabolismo , TranscriptomaRESUMO
Enrofloxacin is a compound that originates from a group of fluoroquinolones that is widely used in veterinary medicine as an antibacterial agent (this antibiotic is not approved for use as a drug in humans). It reveals strong antibiotic activity against both Gram-positive and Gram-negative bacteria, mainly due to the inhibition of bacterial gyrase and topoisomerase IV enzymatic actions. The high efficacy of this molecule has been demonstrated in the treatment of various animals on farms and other locations. However, the use of enrofloxacin causes severe adverse effects, including skeletal, reproductive, immune, and digestive disorders. In this review article, we present in detail and discuss the advantageous and disadvantageous properties of enrofloxacin, showing the benefits and risks of the use of this compound in veterinary medicine. Animal health and the environmental effects of this stable antibiotic (with half-life as long as 3-9 years in various natural environments) are analyzed, as are the interesting properties of this molecule that are expressed when present in complexes with metals. Recommendations for further research on enrofloxacin are also proposed.
Assuntos
Antibacterianos , Infecções Bacterianas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/veterinária , Enrofloxacina/farmacologia , Enrofloxacina/uso terapêutico , Células Eucarióticas , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico , Bactérias Gram-Negativas , Bactérias Gram-PositivasRESUMO
Eleven patients from Yakutia with a new lysosomal disease assumed then as mucopolysaccharidosis-plus syndrome (MPS-PS) were reported by Gurinova et al. in 2014. Up to now, a total number of 39 patients have been reported; in all of them, the c.1492C>T (p.Arg498Trp) variant of the VPS33A gene was detected. Here, we describe the first Polish MPS-PS patient with a novel homozygous c.599G>C (p.Arg200Pro) VPS33A variant presenting over 12 years of follow-up with some novel clinical features, including fetal ascites (resolved spontaneously), recurrent joint effusion and peripheral edemas, normal growth, and visceral obesity. Functional analyses revealed a slight presence of chondroitin sulphate (only) in urine glycosaminoglycan electrophoresis, presence of sialooligosaccharides in urine by thin-layer chromatography, and normal results of lysosomal enzymes activity and lysosphingolipids concentration in dried blood spot. The comparison with other MPS-PS described cases was also provided. The presented description of the natural history of MPS-PS in our patient may broaden the spectrum of phenotypes in this disease.
Assuntos
Mucopolissacaridoses , Proteínas de Transporte Vesicular , Sulfatos de Condroitina/urina , Glicosaminoglicanos/urina , Humanos , Mucopolissacaridoses/sangue , Mucopolissacaridoses/diagnóstico , Mucopolissacaridoses/genética , Mucopolissacaridoses/urina , Mutação , Polônia , Esfingolipídeos/sangue , Proteínas de Transporte Vesicular/genéticaRESUMO
The Hfq protein is a bacterial RNA chaperone, involved in many molecular interactions, including control of actions of various small RNA regulatory molecules. We found that the presence of Hfq was required for survival of plasmid-containing Escherichia coli cells against high concentrations of chloramphenicol (plasmid p27cmr), tetracycline (pSC101, pBR322) and ampicillin (pBR322), as hfq+ strains were more resistant to these antibiotics than the hfq-null mutant. In striking contrast, production of Hfq resulted in low resistance to high concentrations of kanamycin when the antibiotic-resistance marker was chromosome-borne, with deletion of hfq resulting in increasing bacterial survival. These results were observed both in solid and liquid medium, suggesting that antibiotic resistance is an intrinsic feature of these strains rather than a consequence of adaptation. Despite its major role as RNA chaperone, which also affects mRNA stability, Hfq was not found to significantly affect kan and tet mRNAs turnover. Nevertheless, kan mRNA steady-state levels were higher in the hfq-null mutant compared to the hfq+ strain, suggesting that Hfq can act as a repressor of kan expression.This observation does correlate with the enhanced resistance to high levels of kanamycin observed in the hfq-null mutant. Furthermore, dependency on Hfq for resistance to high doses of tetracycline was found to depend on plasmid copy number, which was only observed when the resistance marker was expressed from a low copy plasmid (pSC101) but not from a medium copy plasmid (pBR322). This suggests that Hfq may influence survival against high doses of antibiotics through mechanisms that remain to be determined. Studies with pBR322Δrom may also suggest an interplay between Hfq and Rom in the regulation of ColE1-like plasmid replication. Results of experiments with a mutant devoid of the part of the hfq gene coding for the C-terminal region of Hfq suggested that this region, as well as the N-terminal region, may be involved in the regulation of expression of antibiotic resistance in E. coli independently.
Assuntos
Antibacterianos/farmacologia , Cromossomos Bacterianos/genética , Resistência Microbiana a Medicamentos/genética , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Fator Proteico 1 do Hospedeiro/genética , Mutação , Plasmídeos/genética , Escherichia coli/efeitos dos fármacosRESUMO
Mucopolysaccharidoses (MPS) are inherited metabolic diseases characterized by accumulation of incompletely degraded glycosaminoglycans (GAGs) in lysosomes. Although primary causes of these diseases are mutations in genes coding for enzymes involved in lysosomal GAG degradation, it was demonstrated that storage of these complex carbohydrates provokes a cascade of secondary and tertiary changes affecting cellular functions. Potentially, this might lead to appearance of cellular disorders which could not be corrected even if the primary cause of the disease is removed. In this work, we studied changes in cellular organelles in MPS fibroblasts relative to control cells. All 11 types and subtypes of MPS were included into this study to obtain a complex picture of changes in organelles in this group of diseases. Two experimental approaches were employed, transcriptomic analyses and electron microscopic assessment of morphology of organelles. We analyzed levels of transcripts of genes grouped into two terms included into the QuickGO database, 'Cellular component organization' (GO:0016043) and 'Cellular anatomical entity' (GO:0110165), to find that number of transcripts with significantly changed levels in MPS fibroblasts vs. controls ranged from 109 to 322 (depending on MPS type) in GO:0016043, and from 70 to 208 in GO:0110165. This dysregulation of expression of genes crucial for proper structures and functions of various organelles was accompanied by severe changes in morphologies of lysosomes, nuclei, mitochondria, Golgi apparatus, and endoplasmic reticulum. Interestingly, some observed changes occurred in all/most MPS types while others were specific to particular disease types/subtypes. We suggest that severe changes in organelles in MPS cells might arise from dysregulation of expression of a battery of genes involved in organelles' structures and functions. Intriguingly, normalization of GAG levels by using recombinant human enzymes specific to different MPS types corrected morphologies of some, but not all, organelles, while it failed to improve regulation of expression of selected genes. These results might suggest reasons for inability of enzyme replacement therapy to correct all MPS symptoms, particularly if initiated at advanced stages of the disease.
Assuntos
Fibroblastos , Regulação da Expressão Gênica , Mucopolissacaridoses , Organelas , Linhagem Celular , Fibroblastos/metabolismo , Fibroblastos/ultraestrutura , Humanos , Mucopolissacaridoses/metabolismo , Mucopolissacaridoses/patologia , Organelas/metabolismo , Organelas/ultraestruturaRESUMO
Although mucopolysaccharidoses (MPS) are caused by mutations in genes coding for enzymes responsible for degradation of glycosaminoglycans, storage of these compounds is crucial but is not the only pathomechanism of these severe, inherited metabolic diseases. Among various factors and processes influencing the course of MPS, oxidative stress appears to be a major one. Oxidative imbalance, occurring in MPS and resulting in increased levels of reactive oxidative species, causes damage of various biomolecules, leading to worsening of symptoms, especially in the central nervous system (but not restricted to this system). A few therapeutic options are available for some types of MPS, including enzyme replacement therapy and hematopoietic stem cell transplantation, however, none of them are fully effective in reducing all symptoms. A possibility that molecules with antioxidative activities might be useful accompanying drugs, administered together with other therapies, is discussed in light of the potential efficacy of MPS treatment.
Assuntos
Mucopolissacaridoses/terapia , Estresse Oxidativo/fisiologia , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Terapia de Reposição de Enzimas , Terapia Genética , Glicosaminoglicanos/metabolismo , Humanos , Mucopolissacaridoses/etiologia , Estresse Oxidativo/efeitos dos fármacosRESUMO
Development of therapies for neurodegenerative diseases, disorders characterized by progressing loss of neurons, is a great challenge for current medicine. Searching for drugs for these diseases is being proceeded in many laboratories in the world. To date, several therapeutical strategies have been proposed which, however, are either of insufficient efficacy or at the early preclinical stages. One of the newest concepts is elevated efficiency of degradation of protein aggregates which are causes of 70% of these diseases. Autophagy, i.e. lysosomal degradation of macromolecules, is a process which could be employed in such a strategy Searching for a compound which would not only stimulate autophagy but also reveal safety in a long-term usage and be able to cross the blood-brain-barrier led to studies on one of flavonoids, genistein which occurs at high concentrations in soy. Experiments with this compound indicated its enormous efficiency in removing protein aggregated formed by beta-amyloid, hyperphosphorylated tau protein, and mutant huntingtin. Moreover, using animal models of these diseases, correction of cognitive and motoric symptoms was demonstrated. Considering safety of genistein as well as its ability to crossing the blood-brain-barrier, one may assume that this molecule is a candidate for an effective drug in therapies of not only Alzheimer disease and Huntington disease, but also other disorders caused be protein aggregates. In this article, recent results of studies on the use of genistein in different models of neurodegenerative diseases are summarized, with special emphasis on its autophagy-dependent action.
Assuntos
Doença de Alzheimer , Doença de Huntington , Doenças Neurodegenerativas , Doença de Alzheimer/tratamento farmacológico , Animais , Autofagia , Genisteína/farmacologia , Genisteína/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológicoRESUMO
Although mucopolysaccharidoses (MPS), inherited metabolic diseases from the group of lysosomal storage diseases (LSD), are monogenic disorders, recent studies indicated that their molecular mechanisms are complicated. Storage of glycosaminoglycans (GAGs), arising from a deficiency in one of the enzymes involved in the degradation of these compounds, is the primary cause of each MPS type. However, dysfunctions of various cellular organelles and disturbance of cellular processes have been reported which contribute considerably to pathomechanisms of the disease. Here, we present a complex transcriptomic analysis in which all types and subtypes of MPS were investigated, with special emphasis on genes related to cell activation processes. Complex changes in expression of these genes were found in fibroblasts of all MPS types, with number of transcripts revealing higher or lower levels (relative to control fibroblasts) between 19 and over 50, depending on MPS type. Genes in which expression was significantly affected in most MPS types code for proteins involved in following processes, classified according to Gene Ontology knowledge database: cell activation, cell growth, cell recognition, and cell division. Levels of some transcripts (including CD9, CLU, MME and others) were especially significantly changed (over five times relative to controls). Our results are discussed in the light of molecular pathomechanisms of MPS, indicating that secondary and/or tertiary changes, relative to GAG storage, might significantly modulate cellular dysfunctions and contribute to molecular mechanisms of the disease. This may influence the efficacy of various therapies and suggests why various treatments are not fully effective in improving the complex symptoms of MPS.
Assuntos
Doenças por Armazenamento dos Lisossomos/metabolismo , Mucopolissacaridoses/metabolismo , Adolescente , Ciclo Celular/genética , Ciclo Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Criança , Pré-Escolar , Feminino , Ontologia Genética , Humanos , Lactente , Doenças por Armazenamento dos Lisossomos/genética , Masculino , Transcriptoma/genética , Transcriptoma/fisiologiaRESUMO
Mucopolysaccharidoses (MPS), a group of inherited metabolic disorders caused by deficiency in enzymes involved in degradation of glycosaminoglycans (GAGs), are examples (and models) of monogenic diseases. Accumulation of undegraded GAGs in lysosomes was supposed to be the major cause of MPS symptoms; however, their complexity and variability between particular types of the disease can be hardly explained by such a simple storage mechanism. Here we show that transcriptomic (RNA-seq) analysis of the material derived from fibroblasts of patients suffering from all types and subtypes of MPS, supported by RT-qPCR results, revealed surprisingly large changes in expression of genes involved in various cellular processes, indicating complex mechanisms of MPS. Although each MPS type and subtype was characterized by specific changes in gene expression profile, there were genes with significantly changed expression relative to wild-type cells that could be classified as common for various MPS types, suggesting similar disturbances in cellular processes. Therefore, both common features of all MPS types, and differences between them, might be potentially explained on the basis of changes in certain cellular processes arising from disturbed regulations of genes' expression. These results may shed a new light on the mechanisms of genetic diseases, indicating how a single mutation can result in complex pathomechanism, due to perturbations in the network of cellular reactions. Moreover, they should be considered in studies on development of novel therapies, suggesting also why currently available treatment methods fail to correct all/most symptoms of MPS. We propose a hypothesis that disturbances in some cellular processes cannot be corrected by simple reduction of GAG levels; thus, combined therapies are necessary which may require improvement of these processes.
Assuntos
Fibroblastos/patologia , Mucopolissacaridoses/genética , Transcriptoma , Linhagem Celular , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Glicosaminoglicanos/genética , Glicosaminoglicanos/metabolismo , Humanos , Mucopolissacaridoses/patologia , MutaçãoRESUMO
Mutations in the HTT gene, consisting of expansion of CAG triplets, cause the Huntington's disease (HD), one of the major neurodegenerative disorders. Formation of aggregates of mutant huntingtin (mHTT, the product of the mutant HTT gene) leads to cellular dysfunctions, and subsequent neurodegeneration which manifest clinically as motor abnormalities and cognitive deficits. We recently used immortalized HEK-293 cells expressing the 1st exon of the mutant HTT gene as a cellular model of HD, and showed that the stimulation of autophagy by genistein corrected the mutant phenotype. However, effects of genistein on HD patient-derived cells remained unknown. In this report, we demonstrated that genistein also instigated degradation of mHTT in fibroblasts derived from HD patients. This was assessed as a significant decrease in the levels of HTT in HD fibroblasts measured by Western-blotting, and the disappearance of intracellular mHTT aggregates in cells observed by fluorescent microscopy. Fibroblasts derived from control persons were not affected by genistein treatment. These results indicate that genistein can improve HD phenotype in patient-derived cells, and substantiates the need for further studies of this isoflavone as a potential therapeutic agent.
Assuntos
Autofagia/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Genisteína/farmacologia , Doença de Huntington/induzido quimicamente , Adulto , Animais , Modelos Animais de Doenças , Feminino , Fibroblastos/metabolismo , Humanos , Proteína Huntingtina/efeitos dos fármacos , Doença de Huntington/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Mutação/genética , Proteínas do Tecido Nervoso/metabolismo , Doenças Neurodegenerativas/induzido quimicamenteRESUMO
Autophagy is a process of degradation of macromolecules in the cytoplasm, particularly proteins of a long half-life, as well as whole organelles, in eukaryotic cells. Lysosomes play crucial roles during this degradation. Autophagy is a phylogenetically old, and evolutionarily conserved phenomenon which occurs in all eukaryotic cells. It can be found in yeast Saccharomyces cerevisiae, insect Drosophila melanogaster, and mammals, including humans. Its high importance for cell physiology has been recognized, and in fact, dysfunctions causing impaired autophagy are associated with many severe disorders, including cancer and metabolic brain diseases. The types and molecular mechanisms of autophagy have been reviewed recently by others, and in this paper they will be summarized only briefly. Regulatory networks controlling the autophagy process are usually described as negative regulations. In contrast, here, we focus on different ways by which autophagy can be stimulated. In fact, activation of this process by different factors or processes can be considered as a therapeutic strategy in metabolic neurodegenerative diseases. These aspects are reviewed and discussed in this article.
Assuntos
Autofagia/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Animais , Humanos , Lisossomos/metabolismo , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacosRESUMO
Genetic and immunological diseases, despite many attempts to develop effective treatments, still remain a great challenge for medicine. Current therapies of these diseases consist of pharmacological alleviation of symptoms, rehabilitation and psychological help which, although very important, are not sufficient. Therefore, searching for new therapeutics which could remove the major causes of these diseases is of particular importance for the society. Natural compounds reveal many biological activities which makes them candidates for drugs in such diseases. One of them is genistein, a compound from the group of flavonoids. As it affects multiple processes, genistein has become in the center of interest of many scientists working on diseases of various etiology, course and inheritance. It was used in experimental therapies of some genetic diseases (Huntington's disease, amyotrophic lateral sclerosis Parkinson disease, cystic fibrosis), as well as autoimmunological diseases and allergies. Clinical trials with the use of genistein in treatment of patients suffering from Alzheimer's diseases and mucopolysaccharidosis type III are ongoing. The employment of differential properties of genistein in attempts to treat each of these diseases is of special interest. In this review, detailed molecular mechanisms of genistein action are summarized in the light of therapies of the above mentioned genetic and immunological diseases, including description of therapeutic potentials of each activity of this isoflavone, efficiency of its action, and its potential use as a drug in the future.
Assuntos
Genisteína/farmacologia , Genisteína/uso terapêutico , Doenças do Sistema Imunitário/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Humanos , Doença de Huntington/tratamento farmacológico , Doença de Huntington/genética , Mucopolissacaridose III/tratamento farmacológico , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genéticaRESUMO
Glucocerebrosidase (GCase), encoded by the GBA1 gene, is one of the lysosomal enzymes responsible for hydrolyzing the glycosphingolipids. Deficiency in GCase activity (in patients with two defective alleles of GBA1) leads to glucosylceramide storage in lysosomes which in turn results in the development of the Gaucher diseases, a lysosomal storage disorder, while a heterozygous state may be correlated with the GBA1 mutation-associated Parkinson disease. One of the proposed forms of therapy for these two conditions is the use of pharmacological chaperones which work by facilitating the achievement of the correct conformation of abnormally folded enzymes. Several compounds with chaperone activities against GCase have already been tested, one of which turned out to be ambroxol. Studies conducted on the action of this compound have indeed indicated its effectiveness in increasing GCase levels and activity. However, some data have begun to question its activity as a chaperone against certain GCase variants. Then, a number of articles appeared pointing to other mechanisms of action of ambroxol, which may also contribute to the improvement of patients' condition. This paper summarizes the biological mechanisms of action of ambroxol in Gaucher disease and GBA1 mutation-associated Parkinson disease, focused on its activity as a chaperone, modulator of ERAD pathways, inducer of autophagy, and pain reliever in cellular and animal models as well as in patients. The effects of these activities on the reduction of disease markers and symptoms in patients are also discussed. Consideration of all the properties of ambroxol can help in the appropriate choice of therapy and the determination of the effective drug dose.
Assuntos
Ambroxol , Doença de Gaucher , Glucosilceramidase , Mutação , Doença de Parkinson , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/genética , Doença de Gaucher/metabolismo , Ambroxol/farmacologia , Ambroxol/uso terapêutico , Humanos , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , AnimaisRESUMO
In this report, changes in the levels of various long non-coding RNAs (lncRNAs) were demonstrated for the first time in fibroblasts derived from patients suffering from 11 types/subtypes of mucopolysaccharidosis (MPS). Some kinds of lncRNA (SNHG5, LINC01705, LINC00856, CYTOR, MEG3, and GAS5) were present at especially elevated levels (an over six-fold change relative to the control cells) in several types of MPS. Some potential target genes for these lncRNAs were identified, and correlations between changed levels of specific lncRNAs and modulations in the abundance of mRNA transcripts of these genes (HNRNPC, FXR1, TP53, TARDBP, and MATR3) were found. Interestingly, the affected genes code for proteins involved in various regulatory processes, especially gene expression control through interactions with DNA or RNA regions. In conclusion, the results presented in this report suggest that changes in the levels of lncRNAs can considerably influence the pathomechanism of MPS through the dysregulation of the expression of certain genes, especially those involved in the control of the activities of other genes.