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The Generation of Transgenic Huntington's Disease Miniature Pig
Baxa, Monika ; Motlík, Jan (advisor) ; Procházka, Jan (referee) ; Petr, Jaroslav (referee)
Huntingtons's disease (HD) is devastating neurodegenerative disorder manifesting by motor disturbances, cognitive decline and personal changes. The huge effort to find a cure for HD has brought several promising therapeutic treatments on the scene. Each of the prospective approaches needs to be investigated for safety, tolerability and efficacy. Mouse and rat models were a lot helpful in examination of pathological mechanisms of HD, but they are not sufficient for completion of pre-clinical testing. Therefore, we aimed to generate transgenic HD minipig to overcome the gap between rodents and humans. Minipig transgenic for the first 548 aminoacids of human mutant huntingtin gene (TgHD) under the control of human HD promotor was manipulated by lentiviral transduction of porcine one-cell stage embryos. Currently, six generations of minipigs expressing single copy of N-truncated human mutant huntingtin protein (mtHtt) with a repetition of 124 glutamines are at disposal. The more the model simulates the disease symptoms the better it is for translational research as the efficacy of the cure can be finer evaluated. Hence, the second aim was to demonstrate HD-like phenotype in our model. Testicular degeneration that preceded the clinical symptoms onset was observed as a consequence of expression of mtHtt....
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Porcine models for Huntington disease
Růna Vochozková, Petra ; Motlík, Jan (advisor) ; Bohačiaková, Dáša (referee) ; Fulková, Helena (referee)
The causative role of the huntingtin (HTT) gene in Huntington's disease (HD) has been identified more than 25 years ago. The extension of CAG repeat stretch over 39 repeats in exon 1 of one HTT allele results in full penetrance of this neurodegenerative disorder. While the identification of the causative mutation raised hopes that development of the therapeutic compound will be easily achievable, the patients and their families are still waiting for treatment until now. The main reason for that might be the complex cellular function HTT that makes the determination of the pathologic mechanism difficult and the development of treatments even more challenging. Although a lot of different animal models have been generated until now, establishing a suitable model has still not been achieved yet. Due to its anatomy, physiology, and genetics, the minipig seems to be a suitable candidate for neurodegenerative disease models. Indeed, the existing Transgenic (Tg) Libechov minipig model manifests signs typical for HD in patients, but on the other hand significant inconsistencies have also been observed. The finding of malformation that partially shows the situation in human patients is true for both, the male reproductive tract as well as for the brain. The reason for this might be the fact the genetic...
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Gradual Molecular Changes in Primary Porcine Cells Expressing Mutated Huntingtin
Šmatlíková, Petra ; Motlík, Jan (advisor) ; Trejbalová, Kateřina (referee) ; Reiniš, Milan (referee)
Huntington's disease (HD) is inherited fatal disorder caused by CAG triplet expansions in the huntingtin gene resulting in the expression of mutated huntingtin protein (mtHtt). The main symptoms of HD are neurodegeneration, osteoporosis, testicular degeneration, loss of muscle tissue and heart muscle malfunction, weight loss, metabolic changes, and sleeping disturbances. Since huntingtin protein (Htt) has a role in several biological processes, many molecular mechanisms, like oxidative stress, mitochondrial dysfunction, DNA-damage, and others, are affected by mtHtt. However, its exact pathogenic mechanisms in HD are still not well understood. Transgenic minipig model of HD (TgHD) serves an opportunity to isolate unlimited number of primary cells and unlike primary cells obtained from HD patients, often in the late stages of the disease, the TgHD minipig model allows to monitor molecular changes occurring gradually with age and progression of the disease. Thus, TgHD minipig model and primary cells isolated from it play an important role in investigating and understanding the underlying mechanistic cause of HD. We focused on molecular and cellular changes in primary cells isolated from TgHD minipigs and their wild type (WT) controls at different ages (24, 36, and 48 months). In mesenchymal stem cells...
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Phenotypic study Huntington's disease TgHD minipigs: Appearance and progress of reproductive and biochemical changes
Bohuslavová, Božena ; Motlík, Jan (advisor) ; Roth, Jan (referee) ; Petr, Jaroslav (referee) ; Krylov, Vladimír (referee)
Huntington's disease (HD) is one of the incurable and fatal diseases. HD belongs to the monogenic neurodegenerative diseases. According to the number of the CAG repetitions in the gene coding huntingtin, the onset of the disease is in childhood (5%), in the middle age, which is the most common (90%) and in the older age (5%). Beginning of the disease is manifested by changes in behavior; including problems with coordination and movement. Later, there is a psychological change. The disease leads to death. Until now, there is no effective curative treatment. In 2009, we created a model of the transgenic minipigs (TgHD) carrying the N - terminal part of the human mutant huntingtin (mtHtt) at our Institute in Liběchov. The number of offsprings and the resemblance in physiology and morphology between the pig (Sus scrofa) and humans (Homo sapiens) give us opportunities not only to study changes not only in central nerve organs, but also in peripheral tissues. The reproductive problems of TgHD boars were observed as the first phenotypic changes. Therefore, my work focuses at first on a study of the reproduction parameters of TgHD boars as well as ultrastructural, immunocytochemical and biochemical changes in testes and spermatozoa. In PhD thesis, I described in details the reproductive defects in TgHD...
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Manipulating the mammalian oocyte and embryo - Biological and epigenetic aspects
Fulková, Helena ; Hozák, Pavel (advisor) ; Hampl, Aleš (referee) ; Motlík, Jan (referee)
CONCLUSIONS . By antibodies against ďfferent covalent histone modifications and 5-methylcytosine, we have partialty characterised the epigenetic changes taking place during the oocyte mauration and in early mammalian embryogenesis in the mouse and pig, respectively. o We have also characterised thc epigenetic repogramming activities of cytoplasts derived from oocytes at different stages of maturation after somatic cell nuclear transfer. . We have evaluated the epigenetic effec$ of selected procedures that are currently used for embryo production. . Finally, we have developed a new cryopreservation scheme for oocyte nuclear material storage. orrr research is engaged in the development ofnew bíotechniques as well as elucidating and characterising the epigenetic pÍocesses that take place during normal and abnormal embryogenesis. Abnormal embryonic development is for example often observed in somatic cell nuclear transfer embryos. These techniques can also be potentially used not only in human medicine but also for valuable livestock and endangered species preservation Oy e.g. interspecies nuclear transfer). Especially in human meďcine, attention to the ethical issues associated with these techniques must be paid. It is also clear tbat many biological problems still do exist and these should not be...
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Protein synthesis and protein degradation in mammalian oocyte development
Šušor, Andrej ; Motlík, Jan (advisor) ; Pěknicová, Jana (referee) ; Petr, Jaroslav (referee)
Concr,usroNs We anďysed eucaryoticinitiation t,anslation factorsthat are responsiblefor protein qmthesisin mammalianoocýes. As well we examinedthe affinity.of this factorsto.'mCap, Sepharoseduring in útro conďtion...Inour'laboratorywas optimisedthe protocol for generation of poreine parttrenotesthat serve us as a model for anďysis of. cellular processos in .rygotes with biochemical approaches.. : , , - Antibod}r micÍoanay analysis was used to investigate the: regulation of signalling pathways primarily during meiotic maturationof pig oocytesand subsequentlyin comparisonto other species(bovine,frog andseastar). on the base of proteomeanďysis of maturationof oocýes was chosenUCH-LI molebuleandis studiedin detail in mammalian oocyte. Abnost thorougily was analysed function of UCH-LI in porcine and bovine oocyte using specific inhibitors and overexpression. The mechanism that is involved UCH-LI in antipolyspermydefencein mammalian oocyte was unveiled in our laboratory.
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Following the phenotype development of TgHD minipigs by invasive and noninvasive approach
Ellederová, Zdeňka ; Baxa, Monika ; Vidinská, Daniela ; Bohuslavová, Božena ; Vochozková, Petra ; Šmatlíková, Petra ; Klíma, Jiří ; Valeková, Ivona ; Ardan, Taras ; Juhás, Štefan ; Juhásová, Jana ; Konvalinková, R. ; Klempíř, J. ; Pokorný, M. ; Krupička, R. ; Kauler, J. ; Hansíková, H. ; Motlík, Jan
Recent promising treatments for Huntington’s disease (HD) may require pre-clinical testing in large animals. In 2009, we generated HD transgenic (TgHD) minipigs with one copy encoding the N-terminal part (548 aa) of human huntingtin (HTT) with 124 CAG/CAA repeats integrated into chromosome 1 q24-q25. The successful germ line transmission occurred through four successive generations.
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Double strand DNA breaks response in Huntington´s disease transgenic minipigs
Vaškovičová, Michaela ; Šmatlíková, Petra ; Herbert, A. ; Motlík, Jan ; Šolc, Petr
Huntington’s disease (HD) is progressive neurodegenerative disorder caused by presence of CAG expansion in the huntingtin gene, which gives rise to mutated form of huntingtin protein (mHtt). There is a strong evidence that DNA damage response is compromised by presence of mHtt in cells and increase of double strand DNA breaks (DSBs) is an early event in HD pathology. It was shown, that level of γH2AX is significantly higher in R6/2 mice compared to wild-type animals. Moreover, level of γH2AX is higher also in striatal neurons and fibroblasts of human HD patients. Furthermore, protein p53, key player in DNA damage response, is hyperactivated in cells expressing mHtt and inhibition of p53 or ATM ameliorates phenotypes of HD animal models. However, exact mechanism of mHtt action is not clear and therefore further investigation of mHtt effects on DSBs response is very important for the understanding of HD pathology.
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Oxidative stress in primary porcine fibroblasts expressing mutated huntingtin
Šmatlíková, Petra ; Askeland, G. ; Vaškovičová, Michaela ; Klíma, Jiří ; Motlík, Jan ; Eide, L. ; Ellederová, Zdeňka
Molecular events, such as protein aggregation, mitochondrial dysfunction, and transcriptional dysregulation have been linked to Huntington’s disease (HD) pathogenesis. Oxidative stress has been considered as one of the key players in disease progression. Though, it is still not clear whether oxidative stress causes HD, or if it is a consequence of other primary events.
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