Molecular cell biology is taught as a 2-semester-subject in the first year of the curriculum at t... more Molecular cell biology is taught as a 2-semester-subject in the first year of the curriculum at the Medical School of Pecs, Hungary. During the past two decades, considerable effort has been made to develop an experimental, problem-solving approach in the teaching and assessment of knowledge of the students in our subject. The educational methods include multiple-choice question-based problem-solving tests, analysis of figures from original papers, planning of experiments, and the development of interactive computer programs. Illustrative examples of these methods are presented in this paper.
BACKGROUND Pompe disease is a rare disorder characterised by progressive loss of muscle and respi... more BACKGROUND Pompe disease is a rare disorder characterised by progressive loss of muscle and respiratory function due to acid α-glucosidase deficiency. Enzyme replacement therapy with recombinant human acid α-glucosidase, alglucosidase alfa, is the first approved treatment for the disease, but some patients do not respond, and many do not show a sustained benefit. We aimed to assess the safety and efficacy of an investigational two-component therapy (cipaglucosidase alfa, a novel recombinant human acid α-glucosidase, plus miglustat, an enzyme stabiliser) for late-onset Pompe disease. METHODS We did a randomised, double-blind, parallel-group, phase 3 trial at 62 neuromuscular and metabolic medical centres in 24 countries in the Americas, Asia-Pacific, and Europe. Eligible participants were aged 18 years or older with late-onset Pompe disease, and had either been receiving alglucosidase alfa for at least 2 years or were enzyme replacement therapy-naive. Participants were randomly assigned (2:1) using interactive response technology software, stratified by 6-min walk distance and previous enzyme replacement therapy status, to intravenous cipaglucosidase alfa (20 mg/kg) plus oral miglustat or to intravenous alglucosidase alfa (20 mg/kg) plus oral placebo once every 2 weeks for 52 weeks. Patients, investigators, and outcome assessors were masked to treatment assignment. The primary endpoint was change from baseline to week 52 in 6-min walk distance, assessed using a mixed-effect model for repeated measures analysis for comparison of superiority in the intention-to-treat population (all patients who received at least one dose of study drug). This study is now complete and is registered with ClinicalTrials.gov, NCT03729362. FINDINGS Between Dec 3, 2018, and Nov 26, 2019, 130 patients were screened for eligibility and 125 were enrolled and randomly assigned to receive cipaglucosidase alfa plus miglustat (n=85) or alglucosidase alfa plus placebo (n=40). Two patients in the alglucosidase alfa plus placebo group did not receive any dose due to absence of genotype confirmation of late-onset Pompe disease and were excluded from analysis. Six patients discontinued (one in the alglucosidase alfa plus placebo group, five in the cipaglucosidase alfa plus miglustat group), and 117 completed the study. At week 52, mean change from baseline in 6-min walk distance was 20·8 m (SE 4·6) in the cipaglucosidase alfa plus miglustat group versus 7·2 m (6·6) in the alglucosidase alfa plus placebo group using last observation carried forward (between-group difference 13·6 m [95% CI -2·8 to 29·9]). 118 (96%) of 123 patients experienced at least one treatment-emergent adverse event during the study; the incidence was similar between the cipaglucosidase alfa plus miglustat group (n=81 [95%]) and the alglucosidase alfa plus placebo group (n=37 [97%]). The most frequently reported treatment-emergent adverse events were fall (25 [29%] patients in the cipaglucosidase alfa plus miglustat group vs 15 [39%] in the alglucosidase alfa plus placebo group), headache (20 [24%] vs 9 [24%]), nasopharyngitis (19 [22%] vs 3 [8%]), myalgia (14 [16%] vs 5 [13%]), and arthralgia (13 [15%]) vs 5 [13%]). 12 serious adverse events occurred in eight patients in the cipaglucosidase alfa plus miglustat group; only one event (anaphylaxis) was deemed related to study drug. One serious adverse event (stroke) occurred in the alglucosidase alfa plus placebo group, which was deemed unrelated to study drug. There were no deaths. INTERPRETATION Cipaglucosidase alfa plus miglustat did not achieve statistical superiority to alglucosidase alfa plus placebo for improving 6-min walk distance in our overall population of patients with late-onset Pompe disease. Further studies should investigate the longer-term safety and efficacy of cipaglucosidase alfa plus miglustat and whether this investigational two-component therapy might provide benefits, particularly in respiratory function and in patients who have been receiving enzyme replacement therapy for more than 2 years, as suggested by our secondary and subgroup analyses. FUNDING Amicus Therapeutics.
Pompe disease is caused by the accumulation of glycogen in the lysosomes due to a deficiency of t... more Pompe disease is caused by the accumulation of glycogen in the lysosomes due to a deficiency of the lysosomal acid-α-glucosidase (GAA) enzyme. Depending on residual enzyme activity, the disease manifests two distinct phenotypes. In this study, we assess an enzymatic and genetic analysis of Hungarian patients with Pompe disease. Twenty-four patients diagnosed with Pompe disease were included. Enzyme activity of acid-α-glucosidase was measured by mass spectrometry. Sanger sequencing and an MLPA of the GAA gene were performed in all patients. Twenty (83.33%) patients were classified as having late-onset Pompe disease and four (16.66%) had infantile-onset Pompe disease. Fifteen different pathogenic GAA variants were detected. The most common finding was the c.-32-13 T > G splice site alteration. Comparing the α-glucosidase enzyme activity of homozygous cases to the compound heterozygous cases of the c.-32-13 T > G disease-causing variant, the mean GAA activity in homozygous cases ...
Human fibroblast growth factor 21 (FGF21) is a regulator of lipid and glucose metabolism. It is e... more Human fibroblast growth factor 21 (FGF21) is a regulator of lipid and glucose metabolism. It is expressed in skeletal muscle, and may be a sensitive and specific marker for mitochondrial diseases and other neuromuscular disorders. Serum FGF21 levels were determined in 71 human samples. Thirty patients with mitochondrial disease, 16 patients with myotonic dystrophy type 1 (DM1), 5 patients with facioscapulohumeral dystrophy (FSHD), and 20 healthy controls were enrolled. Serum FGF21 levels were significantly elevated in patients with progressive external ophthalmoplegia and DM1 compared to patients with FSHD, other types of mitochondrial diseases, and controls. In the mitochondrial disorder group, serum FGF21 levels were related to the number of ragged blue fibers. Significant insulin resistance was found in DM1 that might be responsible for FGF21 elevation. FGF21 elevation may be associated with certain types of mitochondrial disease, and is influenced by insulin resistance. This art...
Bilateral pallidal deep brain stimulation (DBS) is an established treatment option for primary ge... more Bilateral pallidal deep brain stimulation (DBS) is an established treatment option for primary generalized and segmental dystonia. In the present study we evaluated the results of our dystonia patients treated by DBS. The surgical results of forty consecutive dystonia patients underwent DBS implantation were analyzed (age: 43.7 +/- 17.7 years; sex: 22 men; etiology: 24 primary and 16 secondary dystonia; topography: 24 generalized, 12 segmental and four hemidystonia; disease duration: 16.1 +/- 9.3 years). Severity of dystonia measured by Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and health-related quality of life measured by EQ-5D scale were obtained preoperatively and compared to the scores obtained at postoperative six months and subsequent yearly follow-ups. The average follow-up lasted 2.5 years (median, 0.5-8 years). In all cases the BFMDRS scores were re-evaluated by a rater blinded to the treatment. Treatment responsiveness was defined as an at least 25% improvement on...
We report the case of a 46-year-old female patient with recurrent rhabdomyolysis. In the backgrou... more We report the case of a 46-year-old female patient with recurrent rhabdomyolysis. In the background of her metabolic myopathy an inherited metabolic disorder of the fatty acid oxidation, very long-chain acyl-coenzyme A-dehydrogenase deficiency was diagnosed. The diagnosis was based on abnormal acyl-carnitine- and urine organic-acid profile in addition to low residual enzyme activity, and was confirmed by genetic testing. After introduction of dietotherapy metabolic crisis necessitating hospital admission has not occurred neither have fixed myopathic changes developed. We present here the differential diagnosis of rhabdomyolysis and exertional muscle complaints, with the metabolic myopathies in focus. The main features of fatty acid oxidation disorders are highlighted, acute and chronic managements of very long-chain acyl-coenzyme A-dehydrogenase deficiency are discussed. Metabolic myopathies respond well to treatment, so good quality of life can be achieved. However, especially in f...
Cyclic phosphatidic acid (cPA; 1-acyl-sn-glycerol-2,3-cyclic phosphate) is an analog of the growt... more Cyclic phosphatidic acid (cPA; 1-acyl-sn-glycerol-2,3-cyclic phosphate) is an analog of the growth factor-like phospholipid mediator lysophosphatidic acid (LPA). As brain tissue is the richest source of cPA we tested its effects on hippocampal neurons from day 16/17 embryonic rat cultured in a serumfree medium. Nanomolar concentrations of cPA elicited a neurotrophic effect and promoted neurite outgrowth that exceeded that of 50 ng/mL nerve growth factor (NGF). Pertussis toxin, the LPA 1 /LPA 3 receptor-selective antagonist dioctylglycerol pyrophosphate, the myristoylated inhibitory pseudosubstrate peptide of protein kinase A (PKI), Wortmannin and PD98059 abolished the neurite-promoting effect.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience
Regeneration in the CNS is blocked by many different growth inhibitory proteins. To foster regene... more Regeneration in the CNS is blocked by many different growth inhibitory proteins. To foster regeneration, we have investigated a strategy to block the neuronal response to growth inhibitory signals. Here, we report that injured axons regrow directly on complex inhibitory substrates when Rho GTPase is inactivated. Treatment of PC12 cells with C3 enzyme to inactivate Rho and transfection with dominant negative Rho allowed neurite growth on inhibitory substrates. Primary retinal neurons treated with C3 extended neurites on myelin-associated glycoprotein and myelin substrates. To explore regeneration in vivo, we crushed optic nerves of adult rat. After C3 treatment, numerous cut axons traversed the lesion to regrow in the distal white matter of the optic nerve. These results indicate that targeting signaling mechanisms converging to Rho stimulates axon regeneration on inhibitory CNS substrates.
A vese- és agydaganatokban az NKT, valamint egy új, NKT sejtekhez hasonló T sejt, a MAIT sejtek i... more A vese- és agydaganatokban az NKT, valamint egy új, NKT sejtekhez hasonló T sejt, a MAIT sejtek invariáns receptora kimutatható, vagyis a sclerosis multiplex plakkokban észlelt NKT sejt deficiencia nem a központi idegrendszeri immunszabályozásssal függ össze, hanem a sclerosis multiplexre jellemző. A daganatokat infiltráló MAIT és NKT sejtek aktivált, döntően CD8+ sejtek, és CD56 molekulát nem expresszálnak, annak ellenére, hogy a perifériás vérben CD56+ csoportban is kimutathatók. A MAIT sejtek gyulladáskeltő citokin környezetben fordulnak elő a daganatokban, vagyis az NKT sejtekhez hasonlóan funkcionálisan heterogének. A MAIT és NKT sejteket tartalmazó CD56+ T sejtek sclerosis multiplex betegek vérében aktiváltak, és citotoxikus molekulákat expresszálnak. SSCP klonalitás módszerrel e sejtek klonális expanzióját mutattuk ki SM-ben. Jelen vannak e sejtek a liquorban is, és NK sejtekhez hasonlóan CD11c molekulát expresszálnak, mely a citokinválasszal összefügghet. Ugyanakkor e sejtek...
Myotonic dystrophy type 1 (DM1) is a common adulthood muscular dystrophy, characterized by muscle... more Myotonic dystrophy type 1 (DM1) is a common adulthood muscular dystrophy, characterized by muscle wasting, myotonia, and multisystemic manifestations. The phenomenon of involuntary muscle contraction during myotonia offers a unique possibility of investigating brain motor functions. This study explores cortical involvement during grip myotonia in DM1. Sixteen DM1 patients were enrolled in the study. Eight patients had apparent grip myotonia, while eight patients did not (control subjects). All patients underwent functional MRI grip task examination twice: prior a warm-up procedure (myotonia was elicited in patients with apparent grip myotonia) and after a warm-up procedure (myotonia was attenuated in patients with apparent grip myotonia). No myotonia was elicited during either examination in patients without apparent grip myotonia. Cerebral blood oxygen level-dependent (BOLD) signals were compared both between groups with and without apparent myotonia, and between pre- and post-warm...
ABSTRACT Molecular cell biology is taught as a two-semester subject during the 12-semester curric... more ABSTRACT Molecular cell biology is taught as a two-semester subject during the 12-semester curriculum of the University Medical School of Pécs. It covers basic methods, facts, processes, theories and clinical aspects of molecular and cellular biology. During the course great emphasis is given to the experimental basis of the subject. Medical students are encouraged and even required to develop problem-solving skills to approach and explore scientific problems in the field. Novel educational and examination forms and techniques have been introduced to help to improve and assess the problem-solving capabilities of students. This paper describes the teaching objectives, forms and tools for education and assessment of knowledge of medical students used during the course in molecular cell biology.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 1999
Regeneration in the CNS is blocked by many different growth inhibitory proteins. To foster regene... more Regeneration in the CNS is blocked by many different growth inhibitory proteins. To foster regeneration, we have investigated a strategy to block the neuronal response to growth inhibitory signals. Here, we report that injured axons regrow directly on complex inhibitory substrates when Rho GTPase is inactivated. Treatment of PC12 cells with C3 enzyme to inactivate Rho and transfection with dominant negative Rho allowed neurite growth on inhibitory substrates. Primary retinal neurons treated with C3 extended neurites on myelin-associated glycoprotein and myelin substrates. To explore regeneration in vivo, we crushed optic nerves of adult rat. After C3 treatment, numerous cut axons traversed the lesion to regrow in the distal white matter of the optic nerve. These results indicate that targeting signaling mechanisms converging to Rho stimulates axon regeneration on inhibitory CNS substrates.
Cyclic phosphatidic acid (cPA; 1-acyl-sn-glycerol-2,3-cyclic phosphate) is an analog of the growt... more Cyclic phosphatidic acid (cPA; 1-acyl-sn-glycerol-2,3-cyclic phosphate) is an analog of the growth factor-like phospholipid mediator lysophosphatidic acid (LPA). As brain tissue is the richest source of cPA we tested its effects on hippocampal neurons from day 16/17 embryonic rat cultured in a serumfree medium. Nanomolar concentrations of cPA elicited a neurotrophic effect and promoted neurite outgrowth that exceeded that of 50 ng/mL nerve growth factor (NGF). Pertussis toxin, the LPA 1 /LPA 3 receptor-selective antagonist dioctylglycerol pyrophosphate, the myristoylated inhibitory pseudosubstrate peptide of protein kinase A (PKI), Wortmannin and PD98059 abolished the neurite-promoting effect.
The goal of the present study was to characterize the effects of RhoA at different stages of nerv... more The goal of the present study was to characterize the effects of RhoA at different stages of nerve growth factor (NGF)-induced neuronal differentiation in the PC12 model. This comparative analysis was prompted by previous studies that reported apparently opposite effects for Rho in different models of neuronal differentiation and regeneration. PC12 cells were transfected with activated V14RhoA or dominant negative N19RhoA under the control of either a constitutive or a steroid-regulated promoter. Upon exposure to NGF, V14RhoA cells continued to proliferate and did not extend neurites; however, they remained responsive to NGF, as indicated by the activation of extracellular signal-regulated kinases. This inability to differentiate was reversed by C3 toxin and activation of cyclic AMP signaling, which inactivate RhoA. N19RhoA expression led to an increase in neurite initiation and branching. In contrast, when the RhoA mutants were expressed after NGF priming, only the rate of neurite extension was altered; V14RhoA clones had neurites approximately twice as long, whereas neurites of N19RhoA cells were approximately 50% shorter than those of appropriate controls. The effects of Rho in neurite regeneration mimicked those observed during the initial stages of morphogenesis; activation inhibited, whereas inactivation promoted, neurite outgrowth. Our results indicate that RhoA function changes at different stages of NGF-induced neuronal differentiation and neurite regeneration.
Molecular cell biology is taught as a 2-semester-subject in the first year of the curriculum at t... more Molecular cell biology is taught as a 2-semester-subject in the first year of the curriculum at the Medical School of Pecs, Hungary. During the past two decades, considerable effort has been made to develop an experimental, problem-solving approach in the teaching and assessment of knowledge of the students in our subject. The educational methods include multiple-choice question-based problem-solving tests, analysis of figures from original papers, planning of experiments, and the development of interactive computer programs. Illustrative examples of these methods are presented in this paper.
BACKGROUND Pompe disease is a rare disorder characterised by progressive loss of muscle and respi... more BACKGROUND Pompe disease is a rare disorder characterised by progressive loss of muscle and respiratory function due to acid α-glucosidase deficiency. Enzyme replacement therapy with recombinant human acid α-glucosidase, alglucosidase alfa, is the first approved treatment for the disease, but some patients do not respond, and many do not show a sustained benefit. We aimed to assess the safety and efficacy of an investigational two-component therapy (cipaglucosidase alfa, a novel recombinant human acid α-glucosidase, plus miglustat, an enzyme stabiliser) for late-onset Pompe disease. METHODS We did a randomised, double-blind, parallel-group, phase 3 trial at 62 neuromuscular and metabolic medical centres in 24 countries in the Americas, Asia-Pacific, and Europe. Eligible participants were aged 18 years or older with late-onset Pompe disease, and had either been receiving alglucosidase alfa for at least 2 years or were enzyme replacement therapy-naive. Participants were randomly assigned (2:1) using interactive response technology software, stratified by 6-min walk distance and previous enzyme replacement therapy status, to intravenous cipaglucosidase alfa (20 mg/kg) plus oral miglustat or to intravenous alglucosidase alfa (20 mg/kg) plus oral placebo once every 2 weeks for 52 weeks. Patients, investigators, and outcome assessors were masked to treatment assignment. The primary endpoint was change from baseline to week 52 in 6-min walk distance, assessed using a mixed-effect model for repeated measures analysis for comparison of superiority in the intention-to-treat population (all patients who received at least one dose of study drug). This study is now complete and is registered with ClinicalTrials.gov, NCT03729362. FINDINGS Between Dec 3, 2018, and Nov 26, 2019, 130 patients were screened for eligibility and 125 were enrolled and randomly assigned to receive cipaglucosidase alfa plus miglustat (n=85) or alglucosidase alfa plus placebo (n=40). Two patients in the alglucosidase alfa plus placebo group did not receive any dose due to absence of genotype confirmation of late-onset Pompe disease and were excluded from analysis. Six patients discontinued (one in the alglucosidase alfa plus placebo group, five in the cipaglucosidase alfa plus miglustat group), and 117 completed the study. At week 52, mean change from baseline in 6-min walk distance was 20·8 m (SE 4·6) in the cipaglucosidase alfa plus miglustat group versus 7·2 m (6·6) in the alglucosidase alfa plus placebo group using last observation carried forward (between-group difference 13·6 m [95% CI -2·8 to 29·9]). 118 (96%) of 123 patients experienced at least one treatment-emergent adverse event during the study; the incidence was similar between the cipaglucosidase alfa plus miglustat group (n=81 [95%]) and the alglucosidase alfa plus placebo group (n=37 [97%]). The most frequently reported treatment-emergent adverse events were fall (25 [29%] patients in the cipaglucosidase alfa plus miglustat group vs 15 [39%] in the alglucosidase alfa plus placebo group), headache (20 [24%] vs 9 [24%]), nasopharyngitis (19 [22%] vs 3 [8%]), myalgia (14 [16%] vs 5 [13%]), and arthralgia (13 [15%]) vs 5 [13%]). 12 serious adverse events occurred in eight patients in the cipaglucosidase alfa plus miglustat group; only one event (anaphylaxis) was deemed related to study drug. One serious adverse event (stroke) occurred in the alglucosidase alfa plus placebo group, which was deemed unrelated to study drug. There were no deaths. INTERPRETATION Cipaglucosidase alfa plus miglustat did not achieve statistical superiority to alglucosidase alfa plus placebo for improving 6-min walk distance in our overall population of patients with late-onset Pompe disease. Further studies should investigate the longer-term safety and efficacy of cipaglucosidase alfa plus miglustat and whether this investigational two-component therapy might provide benefits, particularly in respiratory function and in patients who have been receiving enzyme replacement therapy for more than 2 years, as suggested by our secondary and subgroup analyses. FUNDING Amicus Therapeutics.
Pompe disease is caused by the accumulation of glycogen in the lysosomes due to a deficiency of t... more Pompe disease is caused by the accumulation of glycogen in the lysosomes due to a deficiency of the lysosomal acid-α-glucosidase (GAA) enzyme. Depending on residual enzyme activity, the disease manifests two distinct phenotypes. In this study, we assess an enzymatic and genetic analysis of Hungarian patients with Pompe disease. Twenty-four patients diagnosed with Pompe disease were included. Enzyme activity of acid-α-glucosidase was measured by mass spectrometry. Sanger sequencing and an MLPA of the GAA gene were performed in all patients. Twenty (83.33%) patients were classified as having late-onset Pompe disease and four (16.66%) had infantile-onset Pompe disease. Fifteen different pathogenic GAA variants were detected. The most common finding was the c.-32-13 T > G splice site alteration. Comparing the α-glucosidase enzyme activity of homozygous cases to the compound heterozygous cases of the c.-32-13 T > G disease-causing variant, the mean GAA activity in homozygous cases ...
Human fibroblast growth factor 21 (FGF21) is a regulator of lipid and glucose metabolism. It is e... more Human fibroblast growth factor 21 (FGF21) is a regulator of lipid and glucose metabolism. It is expressed in skeletal muscle, and may be a sensitive and specific marker for mitochondrial diseases and other neuromuscular disorders. Serum FGF21 levels were determined in 71 human samples. Thirty patients with mitochondrial disease, 16 patients with myotonic dystrophy type 1 (DM1), 5 patients with facioscapulohumeral dystrophy (FSHD), and 20 healthy controls were enrolled. Serum FGF21 levels were significantly elevated in patients with progressive external ophthalmoplegia and DM1 compared to patients with FSHD, other types of mitochondrial diseases, and controls. In the mitochondrial disorder group, serum FGF21 levels were related to the number of ragged blue fibers. Significant insulin resistance was found in DM1 that might be responsible for FGF21 elevation. FGF21 elevation may be associated with certain types of mitochondrial disease, and is influenced by insulin resistance. This art...
Bilateral pallidal deep brain stimulation (DBS) is an established treatment option for primary ge... more Bilateral pallidal deep brain stimulation (DBS) is an established treatment option for primary generalized and segmental dystonia. In the present study we evaluated the results of our dystonia patients treated by DBS. The surgical results of forty consecutive dystonia patients underwent DBS implantation were analyzed (age: 43.7 +/- 17.7 years; sex: 22 men; etiology: 24 primary and 16 secondary dystonia; topography: 24 generalized, 12 segmental and four hemidystonia; disease duration: 16.1 +/- 9.3 years). Severity of dystonia measured by Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and health-related quality of life measured by EQ-5D scale were obtained preoperatively and compared to the scores obtained at postoperative six months and subsequent yearly follow-ups. The average follow-up lasted 2.5 years (median, 0.5-8 years). In all cases the BFMDRS scores were re-evaluated by a rater blinded to the treatment. Treatment responsiveness was defined as an at least 25% improvement on...
We report the case of a 46-year-old female patient with recurrent rhabdomyolysis. In the backgrou... more We report the case of a 46-year-old female patient with recurrent rhabdomyolysis. In the background of her metabolic myopathy an inherited metabolic disorder of the fatty acid oxidation, very long-chain acyl-coenzyme A-dehydrogenase deficiency was diagnosed. The diagnosis was based on abnormal acyl-carnitine- and urine organic-acid profile in addition to low residual enzyme activity, and was confirmed by genetic testing. After introduction of dietotherapy metabolic crisis necessitating hospital admission has not occurred neither have fixed myopathic changes developed. We present here the differential diagnosis of rhabdomyolysis and exertional muscle complaints, with the metabolic myopathies in focus. The main features of fatty acid oxidation disorders are highlighted, acute and chronic managements of very long-chain acyl-coenzyme A-dehydrogenase deficiency are discussed. Metabolic myopathies respond well to treatment, so good quality of life can be achieved. However, especially in f...
Cyclic phosphatidic acid (cPA; 1-acyl-sn-glycerol-2,3-cyclic phosphate) is an analog of the growt... more Cyclic phosphatidic acid (cPA; 1-acyl-sn-glycerol-2,3-cyclic phosphate) is an analog of the growth factor-like phospholipid mediator lysophosphatidic acid (LPA). As brain tissue is the richest source of cPA we tested its effects on hippocampal neurons from day 16/17 embryonic rat cultured in a serumfree medium. Nanomolar concentrations of cPA elicited a neurotrophic effect and promoted neurite outgrowth that exceeded that of 50 ng/mL nerve growth factor (NGF). Pertussis toxin, the LPA 1 /LPA 3 receptor-selective antagonist dioctylglycerol pyrophosphate, the myristoylated inhibitory pseudosubstrate peptide of protein kinase A (PKI), Wortmannin and PD98059 abolished the neurite-promoting effect.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience
Regeneration in the CNS is blocked by many different growth inhibitory proteins. To foster regene... more Regeneration in the CNS is blocked by many different growth inhibitory proteins. To foster regeneration, we have investigated a strategy to block the neuronal response to growth inhibitory signals. Here, we report that injured axons regrow directly on complex inhibitory substrates when Rho GTPase is inactivated. Treatment of PC12 cells with C3 enzyme to inactivate Rho and transfection with dominant negative Rho allowed neurite growth on inhibitory substrates. Primary retinal neurons treated with C3 extended neurites on myelin-associated glycoprotein and myelin substrates. To explore regeneration in vivo, we crushed optic nerves of adult rat. After C3 treatment, numerous cut axons traversed the lesion to regrow in the distal white matter of the optic nerve. These results indicate that targeting signaling mechanisms converging to Rho stimulates axon regeneration on inhibitory CNS substrates.
A vese- és agydaganatokban az NKT, valamint egy új, NKT sejtekhez hasonló T sejt, a MAIT sejtek i... more A vese- és agydaganatokban az NKT, valamint egy új, NKT sejtekhez hasonló T sejt, a MAIT sejtek invariáns receptora kimutatható, vagyis a sclerosis multiplex plakkokban észlelt NKT sejt deficiencia nem a központi idegrendszeri immunszabályozásssal függ össze, hanem a sclerosis multiplexre jellemző. A daganatokat infiltráló MAIT és NKT sejtek aktivált, döntően CD8+ sejtek, és CD56 molekulát nem expresszálnak, annak ellenére, hogy a perifériás vérben CD56+ csoportban is kimutathatók. A MAIT sejtek gyulladáskeltő citokin környezetben fordulnak elő a daganatokban, vagyis az NKT sejtekhez hasonlóan funkcionálisan heterogének. A MAIT és NKT sejteket tartalmazó CD56+ T sejtek sclerosis multiplex betegek vérében aktiváltak, és citotoxikus molekulákat expresszálnak. SSCP klonalitás módszerrel e sejtek klonális expanzióját mutattuk ki SM-ben. Jelen vannak e sejtek a liquorban is, és NK sejtekhez hasonlóan CD11c molekulát expresszálnak, mely a citokinválasszal összefügghet. Ugyanakkor e sejtek...
Myotonic dystrophy type 1 (DM1) is a common adulthood muscular dystrophy, characterized by muscle... more Myotonic dystrophy type 1 (DM1) is a common adulthood muscular dystrophy, characterized by muscle wasting, myotonia, and multisystemic manifestations. The phenomenon of involuntary muscle contraction during myotonia offers a unique possibility of investigating brain motor functions. This study explores cortical involvement during grip myotonia in DM1. Sixteen DM1 patients were enrolled in the study. Eight patients had apparent grip myotonia, while eight patients did not (control subjects). All patients underwent functional MRI grip task examination twice: prior a warm-up procedure (myotonia was elicited in patients with apparent grip myotonia) and after a warm-up procedure (myotonia was attenuated in patients with apparent grip myotonia). No myotonia was elicited during either examination in patients without apparent grip myotonia. Cerebral blood oxygen level-dependent (BOLD) signals were compared both between groups with and without apparent myotonia, and between pre- and post-warm...
ABSTRACT Molecular cell biology is taught as a two-semester subject during the 12-semester curric... more ABSTRACT Molecular cell biology is taught as a two-semester subject during the 12-semester curriculum of the University Medical School of Pécs. It covers basic methods, facts, processes, theories and clinical aspects of molecular and cellular biology. During the course great emphasis is given to the experimental basis of the subject. Medical students are encouraged and even required to develop problem-solving skills to approach and explore scientific problems in the field. Novel educational and examination forms and techniques have been introduced to help to improve and assess the problem-solving capabilities of students. This paper describes the teaching objectives, forms and tools for education and assessment of knowledge of medical students used during the course in molecular cell biology.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 1999
Regeneration in the CNS is blocked by many different growth inhibitory proteins. To foster regene... more Regeneration in the CNS is blocked by many different growth inhibitory proteins. To foster regeneration, we have investigated a strategy to block the neuronal response to growth inhibitory signals. Here, we report that injured axons regrow directly on complex inhibitory substrates when Rho GTPase is inactivated. Treatment of PC12 cells with C3 enzyme to inactivate Rho and transfection with dominant negative Rho allowed neurite growth on inhibitory substrates. Primary retinal neurons treated with C3 extended neurites on myelin-associated glycoprotein and myelin substrates. To explore regeneration in vivo, we crushed optic nerves of adult rat. After C3 treatment, numerous cut axons traversed the lesion to regrow in the distal white matter of the optic nerve. These results indicate that targeting signaling mechanisms converging to Rho stimulates axon regeneration on inhibitory CNS substrates.
Cyclic phosphatidic acid (cPA; 1-acyl-sn-glycerol-2,3-cyclic phosphate) is an analog of the growt... more Cyclic phosphatidic acid (cPA; 1-acyl-sn-glycerol-2,3-cyclic phosphate) is an analog of the growth factor-like phospholipid mediator lysophosphatidic acid (LPA). As brain tissue is the richest source of cPA we tested its effects on hippocampal neurons from day 16/17 embryonic rat cultured in a serumfree medium. Nanomolar concentrations of cPA elicited a neurotrophic effect and promoted neurite outgrowth that exceeded that of 50 ng/mL nerve growth factor (NGF). Pertussis toxin, the LPA 1 /LPA 3 receptor-selective antagonist dioctylglycerol pyrophosphate, the myristoylated inhibitory pseudosubstrate peptide of protein kinase A (PKI), Wortmannin and PD98059 abolished the neurite-promoting effect.
The goal of the present study was to characterize the effects of RhoA at different stages of nerv... more The goal of the present study was to characterize the effects of RhoA at different stages of nerve growth factor (NGF)-induced neuronal differentiation in the PC12 model. This comparative analysis was prompted by previous studies that reported apparently opposite effects for Rho in different models of neuronal differentiation and regeneration. PC12 cells were transfected with activated V14RhoA or dominant negative N19RhoA under the control of either a constitutive or a steroid-regulated promoter. Upon exposure to NGF, V14RhoA cells continued to proliferate and did not extend neurites; however, they remained responsive to NGF, as indicated by the activation of extracellular signal-regulated kinases. This inability to differentiate was reversed by C3 toxin and activation of cyclic AMP signaling, which inactivate RhoA. N19RhoA expression led to an increase in neurite initiation and branching. In contrast, when the RhoA mutants were expressed after NGF priming, only the rate of neurite extension was altered; V14RhoA clones had neurites approximately twice as long, whereas neurites of N19RhoA cells were approximately 50% shorter than those of appropriate controls. The effects of Rho in neurite regeneration mimicked those observed during the initial stages of morphogenesis; activation inhibited, whereas inactivation promoted, neurite outgrowth. Our results indicate that RhoA function changes at different stages of NGF-induced neuronal differentiation and neurite regeneration.
Uploads
Papers by Ágnes Sebők