Browsing by study line "Farmakologi"
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(2023)Alpha-beta-hydrolase domain containing proteins (ABHD) are involved in lipid metabolism and its regulation in human and animal cells. Approximately 50 of these proteins have been identified and their physiological and pathophysiological functions are still further investigated. ABHD2, ABHD3, ABHD4, ABHD5, ABHD6, ABHD12 and ABHD16 are involved in the metabolism of glycerin esters and phospholipids, in particular lipid mediator 2-arachidonoylglycerol (2-AG) and its metabolites have a significant effect on neuroinflammation via the endocannabinoid system. ABHD12 and ABHD16A were at the center of focus in this thesis as enzymes regulating phosphatidylserine and pro-inflammatory lysophosphatidylserine. In this study, toxicity of five (5) abietane terpene derivatives was tested using mouse E15/16 prenatal cortical neurons, cultured in 96-well plates. There were totally 8 plates cultured in three different batches, 60 cell containing wells per each plate. Wells from each plate were divided into treatment groups of 17, three concentrations of every five compound, control and VEH groups. Those concentrations were 0,1 µM, 1 µM and 10 µM, and for the last two plates 1 µM, 10 µM and 100 µM. Treatment was also separated into three batches like the cell culturing. After treatment, number of living cortical neurons in each treatment groups were counted. For that, cells were treated with immunofluorescent NeuN and DAPI antigens and the fluorescence was imagined with automated microscope. CellProfiler was used to recognize and count the number of living cortical neurons. Immunofluorescent MAP2 antigens were also used but because the shape of MAP2-fluorescing cells, CellProfiler could not recognize them. Intensity of MAP2-fluorescence were measured from those imaged, so the work would not be wasted. One-way ordinary variance analyze ANOVA was carried out for the data to figure out if there were statistically significant results. For compound TAC174, there were several significant results with different concentrations but unfortunately, some results showed signs of toxicity and others improved cell-growth. Some significant results were also found with compounds TAC121, TAC147 and TAD40 showing sings of toxicity, but reliability of those results was questioned. Only one compound, TAC150 was not showing clear toxicity towards mouse cortical neurons, at least with lower concentrations. For conclusion, there were no clear or significant results if these compounds are toxic for cortical neurons. TAC150 showed the least sings of toxicity, therefore it could possibly be considered for further studies in medical field.
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(2020)Amyotrophic lateral sclerosis (ALS) is a rare fatal neurodegenerative disease in which both the upper and lower motor neurons degenerate. Pathological features of the disease include misfolded proteins and accumulations in the central nervous system. The molecular mechanisms of the disease include neuroinflammation, glutamate induced excitotoxicity, and endoplasmic reticulum stress (ER-stress). Numerous genetic defects have been identified in the background of ALS, the most common mutations are in the C9ORF72, SOD1, TDP43 and FUS genes. For each gene mutation, it is important to develop a reliable animal model of ALS for studying pathology and testing new therapies. The most common and most recently found gene mutation, the C9ORF72 repeat expansion mutation, does not yet have an established animal disesase model. The molecular mechanisms of the disease include neuroinflammation, glutamate induced excitotoxicity, and endoplasmic reticulum stress (ER- stress). There is no drug treatment to cure or slow ALS, so the need for new drug therapies that affect the course of the disease is significant. Cerebral dopamine neurotrophic factor (CDNF) protects and restores dopamine neurons and controls ER-stress in preclinical models of Parkinson’s disease. CDNF has also been shown to improve motor coordination as well as protect spinal cord neurons from cell destruction in ALS genetic SOD1- G93A mouse and TDP-43M337 animal models. The purpose of this master's thesis study was to characterize the changes related to neurodegeneration and neuroinflammation in the new C9ORF72-500 disease model and study ER stress of the SOD1-93A disease model and the effect of CDNF on ER stress in SOD1-model and on inflammation in C9-model. In the first sub-study, brain sections from C9ORF72 transgenic and wild-type mice at different time points were subjected to six different immunohistological stainings. The results were compared at each time point (30, 70 and 170) between the wild type and the transgenic group. In another sub-study, spinal cord sections from CDNF snd vehicle treated SOD1- G93A mice were subjected to immunofluorescence staining, after which the intensity of their ER stress marker, GRP78, was analyzed using a confocal microscope. GFAP stained brain sections from CDNF and vehicle treated C9ORF72 mice were analyzed using microscope and imaging analyses. The results of the first sub-study showed neuroinflammation at 24 weeks timepoint in the transgenic group compared to wild-type mice. Pathological features of C9-ALS, various protein accumulations, were observed only in the transgenic group, mainly at 24 weeks. No neuronal loss was observed in this study. The obtained results support the previously published research results and support the reliability of the studied disease model. In the second sub-study ER stress levels were higher in SOD1-mice compared to wild-type mice. Single intracerebroventrical CDNF injection reduced ER stress in SOD1-G93A transgenic mice almost to the same level as ER stress in wild-type mice. CDNF treatment also showed a tendency for reducing inflammation in hippocampus and motor cortex of C9ORF72 mice. The results confirm the pathological role of ER stress in ALS and show that CDNF reduces ER stress when administered as early in the disease as possible, when neuronal damage begins to occur but does not yet lead to neuronal destruction. CDNF appears to be a promising drug candidate for the treatment of ALS and should therefore be further investigated.
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(2022)Introduction: When people age, the composition of sleep changes and sleep becomes more sensitive to external disturbances, making insomnia also more common. Medication is not the first-line treatment option for insomnia. Benzodiazepines or benzodiazepine receptor agonists for the treatment of insomnia have been in the focus of past studies. The content of the dosing instructions for the supplied medicines has not been studied. The dosing instructions should provide clear instructions on how to dose the medicine prescribed to the patient. The aim of this study was to investigate the content and quality of dosing instructions prescribed for the treatment of insomnia for Finns aged ≥75 years in 2020 based on the prospective reimbursement register data by the Social Insurance Institution of Finland (Kela). Materials and methods: The reimbursed purchases of all medicines by persons aged ≥75 years from 1.1.2020 to 31.12.2020 were selected by ATC code from the medicines data according to the Insomnia: Current Care guidelines. The data was gathered from Kela’s dispensations reimbursed under the National Health Insurance scheme. The dataset consisted of 1,080,843 delivery lines, which were screened, and 328,285 lines were included in the analyses. Dosage instructions were reviewed according to the following predetermined five categories: frequency of use, dose, timing, warnings or remarks, and inappropriate instructions. In addition, 1000 dosing instructions were randomly derived to study the phrasing and appropriateness of the dosing instructions in more detail. Results: In 2020, an average of 3.8 reimbursed hypnotic drug deliveries were made per elderly person. Of the deliveries, 68% were for women. 52% of drug deliveries were partially made later and not by original prescription. In the hypnotic dataset, the three most administered drugs were zopiclone (41%), mirtazapine (34%) and zolpidem (12%). The dosage was prescribed in 98–99% of the dosage instructions. Dosing schedule was reported in 83% of dosing instructions and regularity of use was reported in 57% of them. Only 3-6% of the dosing instructions had comments or warnings. 1–2% of the dosing instructions were vague. The duration or regularity of use was clearly indicated in 5% of the dosing instructions. Only 0.1% of dosage instructions contained instructions for discontinuation or reduction. Discussion: The dose and timing of administration were well reported, but the frequency of use was reported in only about half of the dosing instructions. Only few dosing instructions contained remarks or warnings even though hypnotics are at risk for the elderly. Among the three most administered drugs for the treatment of insomnia were two benzodiazepine receptor agonists, zopiclone and zolpidem. However, they may not be suitable for the elderly according to Beers criteria and their use should be avoided. During 2020, an average of four drug deliveries were made per elderly person for the treatment of insomnia, which may indicate prolonged hypnotics use. In addition, more than half of the deliveries were partially made later and not by original prescription. Thus, several drug packages are prescribed for prescriptions, although the drug-based treatment of insomnia should only be short-lived. Conclusions: There are significant deficiencies in the contents and quality in the dosing instructions for drugs delivered to the elderly for insomnia. Minimum information on dose, timing and duration of use was not found in all dosing instructions in this study. Understandable dosing instructions and the reduction in the amount of medication in the prescription could have a further effect on reducing the long-term use of hypnotics, also increasing the safety of medicine use in the elderly.
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(2022)Multiple Sclerosis (MS) is an incurable autoimmune demyelinating disease affecting the central nervous system (CNS). Although the detailed pathogenesis remains unclear, recent research has highlighted the involvement of B cells. For decades, however, MS research was based on T cell-focused animal models of autoimmune encephalomyelitis (EAE), which do not reflect the involvement of B cells in the pathogenesis. Therefore, B cell-dependent EAE models are hypothesized to allow a better understanding of MS immunohistopathology and may therefore lead to the development of efficient treatments. In our spontaneous relapsing-remitting (RR) EAE model, B cells are recruited from the endogenous repertoire by transgenic myelin oligodendrocyte glycoprotein (MOG) -reactive T cells, causing the development of EAE in 3–4-month-old mice. Interestingly, MOG-specific antibodies are present long before actual onset of clinical disease and can be detected already in 5-week-old RR mice and disease development in RR mice is dependent both on the presence of (presumably MOG-specific) B cells as well as on stimuli provided by intestinal microbiota. Firstly, we evaluated the broader usability of induced germinal center cell (iGB) culture as a model for B cell repertoire studies. Then, by using iGB culture, we studied whether MOG-specific B cells are present in secondary lymphoid organs of younger than 4-week-old and germ-free RR mice. Finally, this study aimed to investigate whether the repertoire of MOG-specific B cells undergoes significant qualitative changes from young healthy mice to older acutely sick RR mice, and whether at the time of disease onset the recruited MOG-specific B cells expand and mature in the cervical nodes (cLN) or in the CNS. To do so, following the hosting-lab’s previous single-cell RNA sequencing (scRNA-seq) of B cells derived from cLN of 5-week-old RR mice, we performed the scRNA-seq of B cells from CNS, spleen, and cLN of acutely sick RR EAE mice. We demonstrated that iGB culture is an unsuitable tool to expand pre-activated B cells, and hence, in our hands it was inappropriate for repertoire studies. However, iGB culture proved to be useful for screening different organs for MOG-specific B lymphocytes, and we found that anti-MOG antibodies were firstly detected in 3-4-week-old RR mice, and MOG-specific B cells were present also in germ-free RR mice. Our scRNA-seq results revealed many highly expanded MOG-specific B cell clonotypes in acutely sick RR mice. Moreover, the B cell repertoire of sick RR mice was more diverse, including IgG1, IgM, IgG2b, IgG2c, and IgG3 isotypes, compared to healthy 5-week-old RR mice that had only IgG1 or IgM isotypes. Two-thirds of the expanded clonotypes were primarily detected in the CNS in sick RR mice, indicating that clonotypes develop further and continue isotype switching within the CNS. We also detected more somatic mutation in the variable region of expanded clones of sick RR mice compared to 5-week-old RR mice. The results of this study clearly show an antigen-driven evolution of the MOG-specific B cell repertoire from healthy young to acutely sick RR mice, which seems to occur mainly in CNS itself. In contrast, cLN are the major initial priming site of MOG-specific B cells in healthy RR mice, even under germ-free conditions. This suggests that commensal microbiota is not required for initial recruitment of MOG-specific B cells, but for the development of EAE. To further validate our encouraging scRNA-Seq results, it is necessary, in future experiments, to confirm the MOG-specificity of expanded clonotypes.
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(2021)Binge eating disorder (BED) is the most common eating disorder characterized by compulsive recurrent binge eating episodes with the sense of a lack of control. During a binge eating episode, one eats a larger amount of food, typically high in fat and/or sugar, than would normally be eaten in a discrete period of time. After the episode, negative emotions, such as shame and self-disgust, are present. However, BED does not include compensatory behavior, such as vomiting or excessive exercise. Due to compulsive and uncontrollable eating behavior, it has been suggested that BED represents a food addiction. Eating energy-dense food activates the dopamine, opioid, and endocannabinoid systems in the brain. This elicits the activation of the reward process. Some drugs and medications affect the same neurotransmitter systems, which may produce neuronal alterations in the reward process, leading to an addiction. Several studies have found that cannabidiol (CBD) reduces the self- administration of cocaine, morphine, alcohol, and sucrose in rodents, suggesting an effect on the reward-response. Some of these effects have been shown to be mediated by cannabinoid receptor 2 and TRPV1 receptor. However, the effects of CBD on bingeing behavior have not been studied up to date. The aim of the study was to investigate the effect of CBD on homeostatic feeding and binge eating behavior in C57BL/6 mice. Five separate experiments were conducted. The first experiment investigated the effect of CBD (15, 50, and 150 mg/kg, i.p.) on locomotor activity in a modified open field test over a 2-hour period. In the second test, the effect of CBD (15, 50, and 150 mg/kg, i.p.) on homeostatic feeding was monitored in non-bingeing mice. Next, a limited intermittent access binge eating model without food deprivation or stressors was inducted. Mice had access to laboratory chow ad libitum, but a high energy diet (high in fat, HED) was presented in 24-hour periods every 5-8 days. Then the effect of CBD (15, 50, and 150 mg/kg, i.p.) on HED and chow intake in bingeing mice was investigated. In the fourth experiment, seven days following the administration, the after effect of CBD was studied by monitoring food intake without CBD treatment. Finally, it was investigated whether the effect of CBD can be inhibited by TRPV1 receptor antagonist AMG9810 (1 mg/kg, i.p). In each test, the food intake was monitored at the time point 0,5, 2,5, and 24 h after CBD treatment. Also, water consumption was measured in each experiment. The results revealed that CBD does not affect locomotor activity or homeostatic feeding at a dose of 15, 50, or 150 mg/kg (i.p). However, the results showed that CBD reduces the intake of HED in a dose-dependent manner (15, 50, or 150 mg/kg; i.p.) and, possibly, increases chow intake. No after effect was observed seven days following the administration. Most likely, TRPV1 does not mediate the effect of CBD on HED intake. Furthermore, no significant effects on water intake were observed. In this study, the core aims were to evaluate whether CBD affects homeostatic feeding or binge eating behavior in mice. The results provided a novel insight into the effects of CBD. The findings indicate that the acute systemic administration of CBD reduces HED intake, and possibly, simultaneously increases chow intake, suggesting a balancing effect on feeding in bingeing mice. However, the role of TRPV1 in this effect remains unclear, and further studies are needed.
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(2021)Parkinsonin tauti on hitaasti etenevä hermorappeumasairaus, jossa mustatumakkeen dopamiinihermosolut tuhoutuvat. Taudille on tyypillistä dopamiinihermosoluissa esiintyvät Lewyn kappaleet, jotka koostuvat pääasiassa väärin laskostuneesta ja kasautuneesta alfasynukleiiniproteiinista. Myös neuroinflammaation uskotaan olevan osa Parkinsonin taudin patofysiologiaa. Nykyiset lääkkeet vaikuttavat ainoastaan taudin oireisiin, joten tarve uusille lääkkeille on suuri. Pilottikokeen tarkoituksena oli selvittää aiheuttaako adenoassosioidun virus- (AAV) vektorin alfasynukleiinin ja alfasynukleiinifibrillien yhdistelmämalli rotilla liikehäiriöitä ja tyrosiinihydroksylaasi- (TH) positiivisten dopamiinihermosolujen tuhoutumista mustatumakkeessa ja hermopäätteiden tuhoutumista aivojuoviossa sekä saadaanko mallilla aikaan neuroinflammatorinen vaste. Varsinaisen pitkän kokeen tarkoituksena oli selvittää aivojen dopamiinihermokasvutekijän (CDNF) mahdollinen neurorestoratiivinen vaikutus tässä mallissa. Alfasynukleiinin kasautumispatologian tasoa ja CDNF:n neurorestoratiivista vaikutusta selvitettiin käyttäytymiskokeilla sekä mustatumakkeen ja aivojuovion TH-vasta-ainevärjäyksillä. Yhdistelmämallista aiheutuvaa neuroinflammatorista vastetta selvitettiin ionisoidun kalsiumia sitovan adapterimolekyylin 1 (Iba1) ja gliaalisen fibrillaarisen happaman proteiinin (GFAP) vasta-ainevärjäyksillä. Pilottikokeen sylinterikokeessa yhdistelmämalli ei indusoinut liikehäiriötä, mutta pitkän kokeen askel- ja sylinterikokeessa mallin osoitettiin aiheuttavan unilateraalille leesiolle tyypillinen liikehäiriö. Pilottikokeen ja pitkän kokeen TH-vasta-ainevärjäyksissä mallin osoitettiin aiheuttavan TH-positiivisten dopamiinihermosolujen tuhoutumista mustatumakkeessa ja hermopäätteiden tuhoutumista aivojuoviossa. Nämä tulokset osoittavat, että yhdistelmämallilla saadaan aikaan alfasynukleiinin kasautumispatologiaa. Pilottikokeessa osoitettiin myös, että yhdistelmämallilla saadaan aikaan neuroinflammatorinen vaste, mikä osoittaa, että malli soveltuu hyvin uusien lääkkeiden vaikutuksen tutkimiseen Parkinsonin tautiin liittyvässä neuroinflammaatiossa. Pitkän kokeen sylinterikokeessa AAV-CDNF:llä ei ollut vaikutusta mallista aiheutuvaan liikehäiriöön. Sen sijaan askeltestissä kämmenen suunnan mittauksessa AAV-CDNF korjasi liikehäiriötä. AAV-CDNF ei kuitenkaan suojannut TH-positiivisia hermosoluja mustatumakkeessa tai hermopäätteitä aivojuoviossa, minkä perusteella johtopäätöstä CDNF:n neurorestoratiivisesta vaikutuksesta ei voida tehdä.
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C-MANF:n farmakokineettiset ominaisuudet ja vaikutukset ALS:n geneettisessä SOD1-G93A-hiirimallissa (2021)Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder caused by degeneration of motor neurons in brain and spinal cord. The degeneration of motor neurons leads to muscle atrophy and paralysis. Currently there is no cure for ALS. Available drugs for ALS can lengthen the survival time by a couple of months. Several factors involve the pathophysiology of ALS, such as endoplasmic reticulum stress and neuroinflammation. Mesencephalic astrocyte-derived neurotrophic factor (MANF) is a protein which has shown neuroprotective effects on animal models of Parkinson disease and brain ischemia. C-terminal fragment of MANF can cross the blood-brain barrier, allowing it to be administered subcutaneously instead of injected directly into the brain. The experimental part consists of two parts. The aim of the first part was to study the pharmacokinetic properties of next generation MANF (C-MANF). The aim of the second part was to elucidate the effect of twice a week administered subcutaneous injection of C-MANF in genetic SOD1-G93A mouse model and its neuroprotective effects by assessing protection of lumbar motor neurons. Pharmacokinetic properties of C-MANF were determined in wild type mice after a single subcutaneous injection of C-MANF at different time points by using indirect ELISA assay. The effects of C-MANF in SOD1-G93A mouse model were assessed by subcutaneous injection of either C-MANF or PBS twice a week and by monitoring clinical score and motor behavior of mice from 10 weeks of age to clinical endpoint. Hematoxylin eosin staining was used to study neuroprotective effects of C-MANF. C-MANF administered subcutaneously is absorbed into the blood circulation and the highest serum concentration of C-MANF is after 60 minutes of dosing. Subcutaneously injected C-MANF also crosses the blood-brain barrier and reach the brain in 120 minutes. C-MANF did not preserve motor function or ameliorated ALS symptoms in SOD1-G93A mouse model. In this study C-MANF did not increase the survival of SOD1-G93A mice. C-MANF did not significantly protect motor neurons from degeneration even though there was a slight trend between the groups. No beneficial effects were observed with C-MANF in SOD1-G93A mouse model and therefore the dose and frequency of administration of C-MANF were not optimal. Subcutaneously injected C-MANF provides a safer dosing option for neurodegenerative disorders.
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(2021)Huntington’s disease (HD) is a rare but devastating neurodegenerative disease, progressively culminating in severe brain atrophy and death. The disease is caused by an inherited mutation resulting in a CAG trinucleotide repeat expansion in the huntingtin gene, leading to the production of a neurotoxic protein, known as mutant huntingtin, with an abnormally long polyglutamine stretch. Even though the genetic background of HD is known, the cellular pathways affected in the disease are complex and not completely understood. Increasing evidence indicates that endoplasmic reticulum (ER) stress – a condition of disturbances in normal ER activity, leading to accumulation and aggregation of misfolded proteins in the ER lumen – is a central factor in the pathogenesis of HD and other neurodegenerative diseases. In the literature review of this thesis, known pathogenic cellular mechanisms of HD and how these cellular mechanisms are connected to ER stress, are discussed. Unpublished data from previous studies in our laboratory have indicated that the ER luminal protein canopy homolog 2 (CNPY2) could play a role in the regulation of neuronal survival, including the viability of mutant huntingtin expressing neurons. The aim of the experimental part of this study was to gain insight into a possible function of CNPY2 in HD, by examining the levels of the protein in neuronal models of HD under various conditions, such as ER stress, and by searching for potential interacting partners of CNPY2 amongst known ER stress regulators. The obtained results show that the levels of CNPY2 are increased in striatal neurons expressing mutant huntingtin, and that the secretion of CNPY2 is increased by these neurons, compared to control neurons expressing normal huntingtin. Further, we show that CNPY2 interacts with the major ER stress regulator binding immunoglobulin protein (BiP) in human neuroblastoma cells treated with the ER stress inducer tunicamycin, and that the intracellular levels of CNPY2 are altered by tunicamycin treatment. Together, these findings indicate that CNPY2 could be involved in the pathogenesis of HD. However, further research on the functions of CNPY2 and its role in ER stress regulation is required to understand the nature of this involvement.
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(2021)Parkinson´s disease (PD) is the second most common neurodegenerative disease in the world after Alzheimer´s disease. There is still no drug that alters the state of the disease. It has been found that Endoplasmic reticulum (ER) stress is one mechanism in PD. ER stress occurs due to accumulation of unfolded proteins. ER stress triggers Unfolded protein response (UPR) that protects against ER stress by decreasing unfolding of proteins. In the beginning, UPR has protective effect, but in prolonged ER stress UPR triggers apoptotic cell death. There are several key mediators in the UPR pathway. Characterisation of ER stress in PD models may be important for the current and future drug development of PD. If ER stress is a significant factor that affects the disease development, it would be important to find a drug that alters these mechanisms and UPR. This may be a way to halt the disease development. Different animal models of PD, like 6-OHDA (6-hydroxydopamine) and MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) model, have similarities in their mechanisms. It has been found that ER stress occurs both in the brain of PD patients and animal models of PD. That is why studying and further characterisation in animal models is relevant. The aim of this study was to characterize ER stress in 6-OHDA rat model. The expression of some key mediators of the UPR were determined in this study. There were male and female Spraque Dawley rats in this experiment. 6-OHDA or saline was injected intrastriatally in 3 spots by stereotaxic surgery. Two weeks after 6-OHDA lesions, amphetamine-induced rotation test was conducted to the rats. The rats were divided into groups based on lesion size according to the results. For this study, the rats were euthanised at week 2 or week 4 post lesion. The rats were euthanised by carbondioxide, and the death was confirmed by decapitation. The brains were collected and stored in -80°C. Striatum and substantia nigra were collected later. Total RNA was isolated from these samples. Part of the RNA sample was used to conduct cDNA synthesis. Finally, the gene expression of Atf4, Ire1α, Xbp1s, Xbp1t, Grp78 and Chop was measured from these cDNA samples by qPCR (quantitative polymerase chain reaction). The qPCR data describes the expression of exact gene. The data was processed prior to statistical analysis. By statistical analysis, it was possible to compare the expression of these genes between 6-OHDA group and vehicle group. In addition, comparison was made between 6-OHDA treated groups at week 2 and 4. According to the results, only Chop expression had increased in 6-OHDA lesioned rats at week 2 compared to the vehicle group. In other genes there were no statistical differences, unlike in several other studies where the expression was found to be increased. Thus, the characterisation of this model requires further studying, possibly by increasing the sample size and studying later time points as well.
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(2020)Parkinson’s disease (PD) is a neurodegenerative disease in which dopaminergic neurons that form the nigrostriatal pathway gradually die. This causes the main motor symptoms of Parkinson’s disease: tremor, rigidity and bradykinesia. While PD affects 1-2% of total population, all currently used medicines are symptomatic, and there is no disease modifying therapy available at present. Although several different animal models for Parkinson’s disease exist, the lack of adequate animal models is often cited as a major obstacle for predicting the clinical success of potential drug candidates. Lewy bodies (LBs) are abnormal aggregates that develop and spread inside nerve cells of human PD patients, their main structural component being α-synuclein. Because α-synuclein is thought to play a major role in the pathology of PD, much research has been focused on it. Different α-synuclein-based animal models of PD exist today, of which the most recent are based on using direct injections of preformed α-synuclein fibrils (PFFs). These new α-synuclein based disease models have helped to understand the disease process in PD better, but cell death in these models takes longer to achieve and is often less pronounced compared to traditional neurotoxin based animal models of PD. The aim of this study was to participate in the development and characterization of a novel mouse model of PD. This new model combines PFF-injections with the commonly used neurotoxin 6-OHDA, which should result in more robust dopamine pathway degeneration than what is seen with the current PFF-based models. The main hypothesis of this study was that the combination of intrastriatal injections of PFFs and a low dose of 6-OHDA would cause gradual spreading of the α-synuclein aggregation pathology in the nigrostriatal dopamine pathway and progressive dopamine neuron loss leading to motor deficits. C57BL/6 mice were stereotactically injected unilaterally with both PFF and 6-OHDA, and their performance was assessed every other week with different behavioral tests until week 12. At the end, brains were collected and optical density of tyrosine hydroxylase (TH) and dopamine transporter (DAT) was measured from striatal sections, and TH and DAT positive cells in the substantia nigra were counted. The amount of Lewy bodies present in the brain slices was also counted from the cortex and substantia nigra areas of the brain. In the histological assays, statistically significant reductions of both TH and DAT were found in the brain sections of the PFF + 6-OHDA combination group and the amount of TH and DAT positive cells were lower in this group compared to the group receiving vehicle treatment only. However, the results of behavioral tests were non-significant, although a non-statistical positive trend in the amphethamine-induced rotations test was observed where mice receiving PFF + 6-OHDA rotated the most. Taken together, combination model that utilizes both PFF and 6-OHDA injections seems like a promising candidate in modelling PD in mice, but much more research and further development of the model is required before this combination model is ready and robust for use in drug development.
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(2021)Mild traumatic brain injury (TBI) is defined as an injury that disrupts the normal functioning of the brain and is the result of external force to the head. It is the most common type of traumatic head injury, and it is common especially in contact sports and within military personnel. Mild TBI typically causes no clear structural changes to the head, but it can induce persistent clinical symptoms, as well as microscopic pathological changes to the brain that may eventually lead to neurodegeneration and increase the risk for several diseases. Mild TBI is a risk factor for several neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, and chronic traumatic encephalopathy. The primary objective of this study was to develop a repetitive mild TBI mouse model for future research purposes in the field of head trauma and neurodegeneration. The injury was induced as a closed head injury with an electromagnetic impactor. Literature and pilot experiments were used to define the parameters of the impactor required to induce a brain injury of desired severity. The characterization criteria of the mild TBI model considered the criteria used to define human mild TBI, as well as long term effects often reported after repetitive mild TBI: neurodegeneration as tau protein related pathology, neuroinflammation, and memory deficits. The secondary objective of this study was to tentatively test a prolyl oligopeptidase (PREP) inhibitor on the behavioral and histological effects of mild TBI. The functioning of the mild TBI model was studied by histopathological and behavioral assessments. After baseline behavioral assessment and repetitive (1 injury every 24 hours altogether 5 times) mild TBI inductions, the mice were monitored for approximately 3 months, during which several rounds of behavioral tests were performed. Barnes maze and novel object recognition tests were used to assess memory functions, and locomotor activity test was used to assess general locomotor activity. After euthanasia, brain histopathology was performed to study the amount of tau protein and the level of neuroinflammation. Due to the low number of animals in the study, the results are directional and need to be confirmed in subsequent studies. The histopathology showed greater amount of neuroinflammation and tau protein in the brains of injured mice, but statistical evaluations could not be made. Memory functions were slightly worse in the injured mice compared to controls, but significance of the results is unclear. Locomotor activity was not influenced by the mild TBIs. PREP inhibition treatment increased the locomotor activity of the mice, but the significance is unclear. The mild TBI model seems promising and the characterization criteria were partially met. The results of the study need to be verified in subsequent studies with a greater amount of animals. The model developed here can be used to study the involvement of head trauma in neurodegeneration, as well as treatment alternatives to changes caused by mild TBIs. As there currently are no curative treatments to neurodegenerative diseases, research regarding neurodegeneration and its risk factors is highly important.
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(2021)Cytochrome P450 (CYP) enzyme inhibition is one of the most common reasons for adverse drug-drug interactions. An especially harmful form of inhibition is time-dependent inhibition (TDI) in which the inhibition potency increases over time and persists even after discontinuation of the drug. Both direct and time-dependent inhibition can be efficiently screened with the so-called cocktail method containing several CYP-selective probe substrates in a single reaction mixture. This method is practical especially in ADME studies of drug development, as it offers lower costs, consumption of fewer reagents and faster implementation in comparison to conventional methods. In addition, the cocktail method can be used to establish new diagnostic CYP inhibitors in vitro. The aim of this Master’s thesis was to participate in the development and optimization of a new cocktail assay method. The method was developed for screening of major drug-metabolizing CYP enzymes in vitro both in a direct and time-dependent manner using pooled human liver microsomes. Based on preliminary testing, included probe substrates were divided into two cocktails to avoid significant inter-substrate interactions: cocktail I containing tacrine/CYP1A2, bupropion/CYP2B6, amodiaquine/CYP2C8, tolbutamide/CYP2C9 and midazolam/CYP3A4, and cocktail II containing coumarin/CYP2A6, (S)-mephenytoin/CYP2C19, dextromethorphan/CYP2D6 and astemizole/CYP2J2. First, cocktail incubation conditions were optimized, followed by the determination of probe reaction kinetics, kinetic parameters (Km, Vmax) and inter-substrate interactions with single- or dual-substrate incubations. Finally, suitable probe substrate concentrations and the composition of cocktails was evaluated based on the obtained results. As a result of assay optimization, optimal incubation conditions for yet unoptimized cocktail II were established. In optimized incubation conditions, all probe reactions exhibited saturable Michaelis-Menten kinetics except for tacrine 1-hydroxylation (CYP1A2), which exhibited biphasic kinetics instead (Km1: 7.36, Km2: 517). The selected probe substrate concentrations were all below or near their respective Km values except for (S)-mephenytoin 4’-hydroxylation (40 µM vs. Km of 12.5 µM); however, its concentration could not be reduced in order to maintain sufficient metabolite formation for UHPLC-MS/MS-analysis. Dual-substrate incubation assays demonstrated a need for the reduction of bupropion concentration below 100 µM due to its inhibitory effects on CYP2C8 and CYP3A4. In addition, chlorzoxazone/CYP2E1 and testosterone/CYP3A4 were tested as complementary probe substrates for the cocktails; however, they proved to be unsuitable for both cocktails due to significant interactions (>40% inhibition). Prior to the deployment of the method, some adjustments of probe substrate concentrations are still required in addition to consideration of the suitability of less commonly used CYP3A4 and CYP2E1 probe reactions to improve cocktail coverage. Lastly, validation of the method with known time-dependent model inhibitors should also be conducted. Besides to improvement of the cocktails, new information was generated on inter-cocktail probe-probe interactions and enzyme kinetics of probe reactions, especially for the less-studied astemizole O-demethylation (CYP2J2) and tacrine 1-hydroxylation (CYP1A2). Generated information can be used, for example, in the development of new cocktails.
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(2021)Neurodegenerative diseases and neuronal injury after trauma are common causes of neuronal loss. Adult brain has only a limited regenerative capability to replace the lost neurons caused by several distinct brain diseases. Direct reprogramming of brain resident cells into neurons could provide a promising strategy for efficiently replacing non-functional neurons. To date, the focus has been put largely on astrocyte-to-neuron reprogramming despite the relatively low yield of newly generated neurons reported in vivo. According to our hypothesis oligodendrocytes possess a more diverge transcriptomic profile when compared to neurons and astrocytes thus allowing better cell-specific targeting of reprogramming. Here, we establish the molecular tools for direct neuronal reprogramming of human oligodendrocytes to neurons. We investigate whether the expression of a known neural fate specification factor under selected oligodendrocyte-specific promoters is sufficient to induce oligodendrocyte-to-neuron transformation. Furthermore, we test the established tools in vitro using an immortalized human oligodendrocyte cell line. Our preliminary data shows that the human ERBB3 promoter and a single transcription factor transfected cells express doublecortin (DCX), an early marker of neuronal identity. Only recently, the direct in vitro reprogramming of human oligodendrocyte precursor cells into functional neurons has been reported. The direct reprogramming of oligodendrocytes into neurons provides an exciting alternative of neuronal replacement for astrocyte-to-neuron reprogramming. Overall, the field of direct reprogramming offers interesting possibilities for regenerative medicine providing a method for the production of newly generated disease and patient-specific cells.
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(2021)Dilated cardiomyopathy is a non-ischemic cardiac disorder predisposing to heart failure, and the characteristics of dilated cardiomyopathy emerge under normal loading conditions. Dilated cardiomyopathy can be consequence of various conditions e.g. genetic mutations, virus infection or toxin exposures. One of the significant causes of familial dilated cardiomyopathy in Finland is mutation S143P in LMNA-gene, coding for A type lamins. Current drug therapy for dilated cardiomyopathy aims to alleviation of symptoms, prevention of complications and progression of the disease, however, efficacy of current therapy is insufficient, and novel therapy strategies are urgently required. Transcription factors are fundamental regulators of gene expression, and GATA4 is a crucial transcription factor both in embryonic and in adult heart and thus an intriguing target for therapeutic manipulation. Compounds targeting GATA4 have shown anti-hypertrophic and cardioprotective effects. Here, effects of two different hypertrophic stimuli, endothelin-1 and mechanical stretch, on human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were examined with high-content analysis and quantitative reverse transcription PCR (qRT-PCR), respectively. One hiPSC-CM line was used as a healthy control, whereas the other carried the S143P mutation in LMNA-gene (DCM-CMs). Additionally, effects of GATA4-targeting compound C-2021 on cardiomyocytes were investigated. In summary, according to proBNP staining, DCM-CMs are more hypertrophied at baseline. DCM-CMs seemed to be less susceptible to mechanical stretch-induced enhancement in BNP gene expression. In addition, compound C 2021 may have anti-hypertrophic properties suggesting it to be a potential drug candidate in cardiac diseases. Finally, lamin A seemed to mislocalize to nucleoplasm instead of nuclear lamina in DCM-CMs.
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(2022)Ischemic heart disease (IHD) and subsequent heart failure are caused by irreversible loss of contractile cardiomyocytes due to low oxygen supply to the heart. As the leading cause of death worldwide, IHD raises an urgent need for regenerative therapies that prevent or reverse loss of cardiomyocytes. The fetal mammalian heart grows by cardiomyocyte proliferation and utilizes glycolysis as main energy metabolism pathway, until it is introduced to increased oxygen and fatty acid supply at birth. Subsequently, cardiac energy metabolism shifts from glycolysis to β-oxidation of fatty acids and cardiomyocytes exit the mitotic cell cycle. Due to cessation of proliferation the heart can no longer regenerate after ischemic injury and responds to it by introduction of maladaptive pathological processes leading to heart failure. To gain deeper insight on the roles of cardiac metabolism pathways and hypoxia in cell cycle activation, we evaluated the effects of pharmacological metabolic modulation and oxygen supply on cardiomyocyte phenotype and hypoxia response. Furthermore, we studied the changes in the metabolic genotype of cardiomyocytes under alterations of oxygen supply. We utilized quantitative reverse transcription PCR (qRT-PCR) to evaluate the effects of hypoxia and metabolic maturation on the expression of genes involved in hypoxia signaling and metabolism of human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs). Additionally, we investigated the effects of five metabolism-modulating compounds on cell cycle and phenotype of both metabolically matured and unmatured hiPSC-CMs, by utilizing high content analysis. We observed presence of hypoxia signaling as an increase in vascular endothelial growth factor A (VEGFA) expression following 3-hour hypoxic exposure. High expression of succinate dehydrogenase complex flavoprotein subunit A (SDHA) in hiPSC-CMs, which was downregulated at hypoxia, confirmed occurrence of oxidative metabolism induced by metabolic maturation. Surprisingly, metabolic maturation tended to increase proliferation and decrease stress response signaling of hiPSC-CMs. Introduction of the TCA cycle intermediate succinate decreased proliferation of metabolically unmatured hypoxic hiPSC-CMs by 8.2 %. Finally, inhibition of the mevalonate pathway and ketogenesis caused no alterations in hiPSC-CM phenotype or cell cycle, but introduction of the ketone body β-hydroxybutyrate tended to increase proliferation, supporting current evidence that ketogenesis plays a role in cardiomyocyte cell cycle regulation. Our observations suggest that hypoxic hiPSC-CMs can be useful in investigating gene expression and phenotype. Even so, additional methodologies are needed for in-depth evaluation of metabolic reprogramming and its effects on cardiomyocyte phenotype.
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(2021)Parkinson’s disease (PD) is a progressive chronic neurodegenerative disorder, which results in the selective loss of dopaminergic neurons in the substantia nigra (SN). The loss of these neurons results in the dysfunction of the nigrostriatal pathway bringing forth the characteristic motor symptoms seen in PD: postural instability, rigidity, slowness of movement and resting tremors. Non-motor symptoms, such as cognitive deficits, depression and impaired olfaction, typically emerge before motor symptoms. Currently available treatments only provide symptomatic relief with diminishing returns over time and no improvements on the overall outcome of the disease. Neurotrophic factors (NTF) have been of particular interest as a possible curative treatment for PD due to their potential for neuroprotection and neurorestoration. Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an NTF that has shown promising results in numerous in vitro and in vivo studies of PD. However, therapy with MANF and other NTFs involves surgical intervention for local administration, as NTFs cannot cross the blood-brain barrier (BBB). Therefore, the therapeutic potential of a systemically administered NTF would be tremendous, as it would lead to a significantly more favorable risk-benefit ratio for the patient. The aim of the current investigation is to evaluate the efficacy of a next generation variant of MANF in the 6-hydroxydopamine toxin-induced unilateral lesion rat model of PD. Prior in vivo results suggested that subcutaneously injected MANF variant is able to penetrate the BBB. Amphetamine-induced rotational behavior (AMPH-ROTO) was used to evaluate the severity of the unilateral lesions during the experiment every other week until the end of the experiment at week eight. Animals were divided into treatment groups during week two based on their AMPH-ROTO results. Animals received MANF variant either subcutaneously through an implanted osmotic minipump at two different dosages or as a single dose divided into three separate intrastriatal injections. Tyrosine hydroxylase (TH) immunohistochemical staining was performed on brain sections collected from the striatum and SN for data analysis. In addition to AMPH-ROTO results, the efficacy of treatment was determined via the optical density of TH-positive striatal fibers and the number of TH-positive cells in the SN. Statistically significant differences (defined by p < 0.05 and a non-zero mean difference at a 95 % confidence interval) were observed only in the number of TH-positive cells in the SN favoring intrastriatal MANF variant treatment over both intrastriatal MANF and the vehicle treatment. The main concern regarding the validity of the results was related to the heterogeneous lesion sizes in different treatment groups possibly resulting in unsuccessful randomization due to excessive baseline differences. The inadvertent negative effects of this was further exacerbated by low a priori statistical power, which in the end had likely caused inflated effect sizes. Thus, assessment of the definitions of the used statistical parameters and the limitations of the experimental design suggest that presently, the efficacy of the MANF variant could not be evaluated reliably, in spite of the statistically significant result.
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(2019)Farmasian ammattilaiset ovat lääkealan asiantuntijoita, joilta vaaditaan uudenlaista osaamista muun muassa teknologiakehityksen myötä. Nykypäivän asiantuntijuus edellyttää alakohtaisen eli sisällöllisen osaamisen lisäksi geneerisiä eli yleisiä taitoja ja ammatti-identiteetin muodostumista. Geneerisillä taidoilla tarkoitetaan yleishyödyllisiä taitoja, kuten ongelmanratkaisu- ja kommunikointitaitoja. Ammatti-identiteetillä tarkoitetaan käsitystä omasta työminästä, jonka avulla omaa roolia ja työnkuvaa järkeistetään. Näiden elementtien muodostamaa osaamisen kokonaisuutta kutsutaan kompetenssiksi. Asiantuntijoilta vaadittavan osaamisen muutos on ohjannut yliopistoja vastaamaan paremmin työelämän tarpeisiin. Helsingin yliopistossa toteutettiin Iso Pyörä -koulutusuudistus, jossa koulutusohjelmia uudistettiin komeptenssilähtöisesti. Kaikkiin koulutusohjelmiin ja opintojaksoihin lisättiin osaamistavoitteet, jotka opiskelijoiden tulisi saavuttaa valmistumiseensa mennessä. Osaamistavoitteiden täyttymistä edistää esimerkiksi portfoliotyöskentely, minkä avulla opiskelijat pääsevät hyödyntämään ja kehittämään reflektiotaitojaan. Opiskelijat voivat tuoda opetuksen kehittämiseen aivan uudenlaista näkökulmaa avatessaan käsityksiään esimerkiksi hyvistä opetusmenetelmistä, mitkä ovat auttaneet heitä saavuttamaan laaditut osaamistavoitteet. Toisaalta opiskelijoiden näkökulmasta saadaan tietoa, mikä osaaminen voidaan kokea puutteelliseksi, jolloin opetuksen kehittäminen on mahdollista. Tutkimuksen tavoitteena oli selvittää opiskelijoiden käsityksiä omasta osaamisestaan ja ammatti-identiteetistään sekä millä tasoilla opiskelijat reflektoivat osaamistaan. Tutkimuksessa analysoitiin vuoden 2017 kolmannen vuosikurssin kandiportfolion loppureflektioesseet käyttäen aineistolähtöistä sisällönanalyysimenetelmää. Esseissä opiskelijat reflektoivat osaamistaan suhteessa farmaseutin tutkinnolle asetettuihin osaamistavoitteisiin ja pohtivat omaa ammatti-identiteettiään. Tulosten mukaan opiskelijat saavuttivat monipuolista osaamista lääkkeiden ja lääkehoitojen näkökulmasta sekä kehittivät geneerisiä taitojaan. Puutteellisesti hallittiin useimmiten kielitaito sekä yrityksen ja yhteiskunnan taloudelliset periaatteet. Opiskelijoiden mukaan farmaseutin ammatti-identiteettiä määrittelevät erityisesti lääkeosaaminen ja terveydenhuolto sekä ammatin arvostaminen. Opiskelijoiden pohtimat valmiudet mukailivat osaamistavoitteita. Opiskelijat osasivat arvioida omaa osaamistaan ja nostaa esille vahvuuksiaan ja heikkouksiaan. Opetussuunnitelmaan on onnistuttu sisällyttämään geneeristen taitojen opetus, sillä opiskelijat kokivat saavuttaneensa näitä taitoja pääasiassa hyvin. Opetusta tulisi kehittää kielitaidon ja liiketalouden kohdalla, sillä nämä koettiin usein puutteellisesti hallituksi. Ammatti-identiteettikäsitykset mukailivat kirjallisuutta, sillä muissa tutkimuksissa on saatu samankaltaisia tuloksia.
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(2020)The ability to regulate release of noradrenaline, dopamine and GABA is one of the most important roles of the nicotinic receptors. The release of neurotransmitters following stimulation of nicotinic receptors is addressed in the thesis, with focus on dopamine and noradrenaline. Release of neurotransmitters, mediated through nicotinic receptors, has been researched using various methods, including brain slices, microdialysis and synaptosomes. Research using synaptosomes have provided valuable information regarding nicotinic receptors and their ability to regulate neurotransmitter release. Research using receptor specific antagonists have provided information regarding the stoichiometry of nicotinic receptor in different regions of the brain. The primary focus in the thesis, was the characterization of [3H]dopamine release following stimulation of nicotinic receptors with varenicline and acetylcholine, using synaptosomes from mouse striatum. Using a-conotoxin-MII, the [3H]dopamine release was divided into a-conotoxin- MII-resistant and -sensitive release. [3H]Dopamine release was mediated through a6b2*- and a4b2*-receptors from striatal synaptosomes. The involvement of other receptors could not be ruled out, but based on these results and results from previous studies, the involvement of other nicotinic receptors is supposedly low.
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(2021)Current treatments for major depressive disorder have notable limitations including the delay achieving the therapeutic effect. Ketamine has been shown to alleviate the symptoms of depression rapidly and promising findings have also been found when using nitrous oxide. However, the mechanisms behind rapid antidepressant effect are not fully discovered. It seems that rapid-acting treatments alter brain energy metabolism, enhance synaptic plasticity, and repair neuronal dysfunction connected to depression. Particularly, the activation of brain derived neurotrophic factor (BDNF) mediated tropomyosin receptor kinase B (TrkB) signaling has been connected to rapid antidepressant effect. Fasting is also known to induce BDNF production and it is thought to activate BDNF-TrkB signaling. In addition, both of these treatments alter the brain energy metabolism. The objective of this study was to find out how fasting and nitrous oxide alone and in combination affect the rapid antidepressant effect and synaptic plasticity related BDNF-TrkB signaling in mice. Another aim of the research was to determine whether the body temperature changes after these treatments as a marker of metabolic rate. The analyzed brain samples of the mice were collected 15 minutes after cessation of nitrous oxide administration. As a result, it was found that the fasting protocol used in this study did not activate the studied BDNF-TrkB signaling. However, after nitrous oxide administration, the studied signaling and markers related to synaptic plasticity were partly activated. The results from the combination of nitrous oxide and fasting were similar compared to nitrous oxide administration only. It is therefore conceivable, that the effects were caused exclusively by nitrous oxide. Furthermore, a fascinating finding related to energy metabolism was that nitrous oxide reduced the body temperature of the mice significantly 15 minutes after cessation of the gas administration. Overall, these results are promising and consistent with previous research indicating that nitrous oxide administration could be related to induced synaptic plasticity and therefore have antidepressant associated effects. Nitrous oxide could be used to understand the mechanisms behind rapid antidepressant effect and it could be a potential option to treat depression in the future. Based on these results, it seems that energy metabolism could be related to rapid antidepressant effect. It also supports the observations that all different rapid-acting treatments alter the brain energy metabolism.
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(2022)Mild traumatic brain injury (mTBI) is an insult to the brain caused by an external force. Typically contact sport players and military soldiers are prone to mTBI. TBI events trigger pathological processes in the brain and may cause long-term and progressive damages. Increased formation and accumulation of misfolded toxic protein aggregates in the brain leading to neuronal death has been observed after mTBI. In particular, repetitive mTBIs are a risk factor for the development of many neurodegenerative diseases, such as chronic traumatic encephalopathy, Alzheimer’s disease, Parkinson’s disease and amyotrophic lateral sclerosis. As there is no curative treatment to neurodegenerative diseases, research regarding neurodegenerative processes is highly important. Prolyl oligopeptidase (PREP) negatively regulates functions of protein phosphatase 2A (PP2A). It has been shown that PP2A activity is decreased in the brain of those with neurodegenerative diseases and TBI patients, which is thought to be a contributing factor to the development of pathologies of neurodegenerative diseases. The primary objective of this study was to study behavioural changes after repeated mild TBI in PREP knockout mice. The aim was to model mild repeated brain injuries that are common, for instance, in contact sports and that are not accompanied by skull fractures or brain swelling. The intension was to clarify the involvement of the PREP enzyme in behavioural changes induced by repeated mTBI’s and to elucidate long-term pathological changes in the brain. The injury was induced as a closed-head injury with an electromagnetic impactor with one hit every 24 hours and altogether 5 times. A locomotor activity test was performed before the induction of brain injury and was repeated 3 times after mTBI induction. Barnes maze test was used to assess memory and learning functions. In this thesis the brain samples from a previous study were included to also determine the accumulation of total tau protein in wild-type mice. The wild- type mice were administered with either the PREP inhibitor KYP-2047 or HUP-46 10 mg/kg (i.p.) immediately after each hit. After euthanasia, the Western blot assay and immunostaining were performed to study the amount of phosphorylated tau, neuroinflammation, activity of PP2A and autophagy. No differences were found between the sham group and TBI group on the locomotor activity and Barnes maze tests in PREP knockout mice. There was no consistency in total tau protein in wild-type mice treated with PREP inhibitors. In PREP knockout mice there was an upward trend in PP2A levels after mTBI. Repeated mTBI increased markers of phosphorylated tau and neuroinflammation significantly. No significant difference was observed in autophagic function. The results of this thesis are indicative. Due to the low number of animals, the results need to be confirmed in subsequent studies with greater amounts of animals. Based on the results, it seems that absence of the PREP enzyme protects from memory impairments after repeated mTBI. Increased tau protein phosphorylation and neuroinflammation were observed in the TBI group which indicate that PREP alone is not responsible for the development of pathological changes.
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