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Functional and molecular compensation of the of dopaminergic nigrostriatal system degeneration in relation to early Parkinson's disease
Nucleolar activity in neurodegenerative diseases Grzegorz Kreiner1, Rosanna Parlato2 Department
of Brain Biochemistry, Institute of Pharmacology, Polish Academy of Sciences, PL 31-343 Kraków, Poland; Department of Molecular Biology of the Cell I, German Cancer Research Center (DKFZ), DE 69-120 Heidelberg, Germany
Neurodegenerative diseases are associated with proteasomal and mitochondrial dysfunction, increased accumulation of oxygen free radicals leading to alteration of the cellular defense mechanisms and subsequent cell death. The inhibition of protein synthesis represents a basic response to cope with stressful conditions. The nucleolus, being a center of ribosomal RNA (rRNA) synthesis, is an essential stress sensor controlling cellular physiology and homeostasis. However, the possible function of nucleolus in neurodegeneration has not yet been profoundly explored. Nevertheless, it has been shown that nucleolar malfunction contributes to the pathology of several human genetic disorders, such as Werner syndrome, dyskeratosis congenita and Treacher Collins syndrome and predisposes to certain forms of cancer. Moreover, nucleolar size decline is associated with aging, decreased rRNA synthesis have been found in age-related neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease and abnormal nucle-
oli were also reported in cellular models of Huntington’s disease. The cellular and molecular alterations associated with impaired nucleolar activity (a term called “nucleolar stress”) have just started to be systematically explored in the central nervous system, by animal models lacking rRNA synthesis in specific neurons. These studies revealed that nucleolar activity is necessary for neuronal survival but with different modalities between and within cell types. Nucleolar function controls mitochondrial activity and critical stress signaling pathways mimicking hallmarks of human neurodegenerative diseases. This lecture will focus on the modes of action of nucleolar stress and discuss how the manipulation of nucleolar activity might underscore novel strategies to extend neuronal function and survival. Acknowledgments: This work was supported by the grant no. 2011/03/B/NZ7/05949 financed by National Science Centre and statutory funds of the Institute of Pharmacology.
Functional and molecular compensation of the of dopaminergic nigrostriatal system degeneration in relation to early Parkinson’s disease Katarzyna Kuter1,2, Urszula G³owacka1, Klemencja Berghauzen-Maciejewska1, Krystyna Ossowska1, Manuela Kratochwil2, Norbert A. Dencher2 Department
of Neuro-Psychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smêtna 12, PL 31-343 Kraków, Poland; Physical Biochemistry, Department of Chemistry, Darmstadt University of Technology, Petersenstr. 22, D-64287 Darmstadt, Germany
Severe degeneration of the dopaminergic nigrostriatal system is a cause of the motor disability in Parkinson’s disease (PD). First movement disorder signs are observed after the irreversible loss of almost 70% of neurons in substantia nigra (SN). This proves existence of potent compensatory mechanisms, preventing appearance of the symptoms at the preclinical
10
Pharmacological Reports, 2013, 65, suppl.
stages of disease. The survived neurons increase their activity in order to compensate for the degeneration, so their energy demand is probably higher, therefore the functional adaptation of mitochondria is especially interesting in this aspect. We have prepared rat model of selective nigrostriatal dopaminergic system degeneration by injection of
XVIIIJD International Congress of the Polish Pharmacological Society Symposia
6-OHDA into medial forebrain bundle. Three days after the operation behavioral analysis revealed decreased locomotor activity in lesioned rats comparing to sham operated controls. Interestingly 4 weeks post lesion all motor deficits disappeared even though histological verification showed progressing decrease in number of dopaminergic cells in SN by 16% and 41% after 3 days and 4 weeks post lesion respectively. The dopamine levels decreased first in the striatum by 50% already after 3 days and remained low, while in SN its level dropped by 37% only after 4 weeks.
In this model we explored the role of mitochondria in the intrinsic potential of the brain to spontaneously compensate for the degeneration of dopaminergic neurons in the nigrostriatal system. The study focused on activity and stochiometry of mitochondrial complexes assembly into supercomplexes – influencing their stability and energy production efficacy. The study was supported by the Statutory Funds of the Institute of Pharmacology, PAS, Kraków, Poland, DAAD scholarship to KK and Darmstadt University of Technology funds.
Is it possible to treat Parkinson Disease with iPS cells? Pros and Cons Marcin Majka, Maciej Su³kowski Department of Transplantation, Jagiellonian University Collegium Medicum, Wielicka 265, PL 30-663 Kraków, Poland
In a rapidly aging population, neurodegenerative diseases affect growing number of people. For the majority of patients there is no efficient treatment available today. That is the case with Parkinson’s Disease (PD). It is an age-dependent disorder characterized by motion problems including resting tremor, slowed movement, postural instability and muscles rigidity. Despite a lot of effort from several laboratories around the word the PD still remains the incurable disease. However, basing on the latest advances in the field of stem cell research and development of induced pluripotent stem (iPS) cells, we might be facing the new opening in the treatment of PD. Recently, several papers were published showing that iPS could be differentiated toward dopaminergic neurons and improve the PD symptoms in animal models. IPS cells were also used to model the PD through a genome editing and incorporation of PD re-
lated mutations. In our project we focused on developing the safe strategy for using iPS in PD. The major problem that keeps us from using iPS cells in a clinic is their ability to form teratomas. Thus, we developed the iPS cells-based cell replacement therapy for PD patients that have the “safety exit” built-in. To accomplish that we generated the iPS cells that contained the “suicide” thymidine kinase (TK) gene. After gancyclovir treatment cells expressing the TK undergo apoptosis. To make the approach more specific we introduced the TK gene under OCT3/4 promoter. Thus, only iPS cells that did not undergo differentiation were killed. We tested the effectiveness of our strategy in long term NOD-SCID mice model. We strongly believe that results obtained in our and others studies will help to develop new treatment for PD and other neurodegenerative diseases using iPS cells and their derivatives.
Pharmacological Reports, 2013, 65, suppl.
11
of Brain Biochemistry, Institute of Pharmacology, Polish Academy of Sciences, PL 31-343 Kraków, Poland; Department of Molecular Biology of the Cell I, German Cancer Research Center (DKFZ), DE 69-120 Heidelberg, Germany
Neurodegenerative diseases are associated with proteasomal and mitochondrial dysfunction, increased accumulation of oxygen free radicals leading to alteration of the cellular defense mechanisms and subsequent cell death. The inhibition of protein synthesis represents a basic response to cope with stressful conditions. The nucleolus, being a center of ribosomal RNA (rRNA) synthesis, is an essential stress sensor controlling cellular physiology and homeostasis. However, the possible function of nucleolus in neurodegeneration has not yet been profoundly explored. Nevertheless, it has been shown that nucleolar malfunction contributes to the pathology of several human genetic disorders, such as Werner syndrome, dyskeratosis congenita and Treacher Collins syndrome and predisposes to certain forms of cancer. Moreover, nucleolar size decline is associated with aging, decreased rRNA synthesis have been found in age-related neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease and abnormal nucle-
oli were also reported in cellular models of Huntington’s disease. The cellular and molecular alterations associated with impaired nucleolar activity (a term called “nucleolar stress”) have just started to be systematically explored in the central nervous system, by animal models lacking rRNA synthesis in specific neurons. These studies revealed that nucleolar activity is necessary for neuronal survival but with different modalities between and within cell types. Nucleolar function controls mitochondrial activity and critical stress signaling pathways mimicking hallmarks of human neurodegenerative diseases. This lecture will focus on the modes of action of nucleolar stress and discuss how the manipulation of nucleolar activity might underscore novel strategies to extend neuronal function and survival. Acknowledgments: This work was supported by the grant no. 2011/03/B/NZ7/05949 financed by National Science Centre and statutory funds of the Institute of Pharmacology.
Functional and molecular compensation of the of dopaminergic nigrostriatal system degeneration in relation to early Parkinson’s disease Katarzyna Kuter1,2, Urszula G³owacka1, Klemencja Berghauzen-Maciejewska1, Krystyna Ossowska1, Manuela Kratochwil2, Norbert A. Dencher2 Department
of Neuro-Psychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, Smêtna 12, PL 31-343 Kraków, Poland; Physical Biochemistry, Department of Chemistry, Darmstadt University of Technology, Petersenstr. 22, D-64287 Darmstadt, Germany
Severe degeneration of the dopaminergic nigrostriatal system is a cause of the motor disability in Parkinson’s disease (PD). First movement disorder signs are observed after the irreversible loss of almost 70% of neurons in substantia nigra (SN). This proves existence of potent compensatory mechanisms, preventing appearance of the symptoms at the preclinical
10
Pharmacological Reports, 2013, 65, suppl.
stages of disease. The survived neurons increase their activity in order to compensate for the degeneration, so their energy demand is probably higher, therefore the functional adaptation of mitochondria is especially interesting in this aspect. We have prepared rat model of selective nigrostriatal dopaminergic system degeneration by injection of
XVIIIJD International Congress of the Polish Pharmacological Society Symposia
6-OHDA into medial forebrain bundle. Three days after the operation behavioral analysis revealed decreased locomotor activity in lesioned rats comparing to sham operated controls. Interestingly 4 weeks post lesion all motor deficits disappeared even though histological verification showed progressing decrease in number of dopaminergic cells in SN by 16% and 41% after 3 days and 4 weeks post lesion respectively. The dopamine levels decreased first in the striatum by 50% already after 3 days and remained low, while in SN its level dropped by 37% only after 4 weeks.
In this model we explored the role of mitochondria in the intrinsic potential of the brain to spontaneously compensate for the degeneration of dopaminergic neurons in the nigrostriatal system. The study focused on activity and stochiometry of mitochondrial complexes assembly into supercomplexes – influencing their stability and energy production efficacy. The study was supported by the Statutory Funds of the Institute of Pharmacology, PAS, Kraków, Poland, DAAD scholarship to KK and Darmstadt University of Technology funds.
Is it possible to treat Parkinson Disease with iPS cells? Pros and Cons Marcin Majka, Maciej Su³kowski Department of Transplantation, Jagiellonian University Collegium Medicum, Wielicka 265, PL 30-663 Kraków, Poland
In a rapidly aging population, neurodegenerative diseases affect growing number of people. For the majority of patients there is no efficient treatment available today. That is the case with Parkinson’s Disease (PD). It is an age-dependent disorder characterized by motion problems including resting tremor, slowed movement, postural instability and muscles rigidity. Despite a lot of effort from several laboratories around the word the PD still remains the incurable disease. However, basing on the latest advances in the field of stem cell research and development of induced pluripotent stem (iPS) cells, we might be facing the new opening in the treatment of PD. Recently, several papers were published showing that iPS could be differentiated toward dopaminergic neurons and improve the PD symptoms in animal models. IPS cells were also used to model the PD through a genome editing and incorporation of PD re-
lated mutations. In our project we focused on developing the safe strategy for using iPS in PD. The major problem that keeps us from using iPS cells in a clinic is their ability to form teratomas. Thus, we developed the iPS cells-based cell replacement therapy for PD patients that have the “safety exit” built-in. To accomplish that we generated the iPS cells that contained the “suicide” thymidine kinase (TK) gene. After gancyclovir treatment cells expressing the TK undergo apoptosis. To make the approach more specific we introduced the TK gene under OCT3/4 promoter. Thus, only iPS cells that did not undergo differentiation were killed. We tested the effectiveness of our strategy in long term NOD-SCID mice model. We strongly believe that results obtained in our and others studies will help to develop new treatment for PD and other neurodegenerative diseases using iPS cells and their derivatives.
Pharmacological Reports, 2013, 65, suppl.
11