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  • Lähdeniemi, Veera (2021)
    Drug metabolism is a series of enzyme catalysed processes that modify foreign compounds into a form that is more easily excreted from the body. Compounds can affect the activity of metabolizing enzymes and this may lead to toxic concentrations of a drug that is metabolized via the enzyme. With prodrugs, on the other hand, the drug might not achieve its biologically active form and therefore the treatment will not be effective. Recognizing and preventing metabolic interactions is important already in the early stages of drug discovery and development. Cytochrome P450 (CYP) enzyme inhibition is one of the major reasons for adverse drug-drug interactions (DDIs). The inhibition can be time-dependent (TDI), which means that the potency of inhibition increases over time. TDI may be reversible or irreversible, latter being more severe as new enzymes need to be produced in the body to restore the enzymatic activity. IC50 shift assay is a method that gives information of new compounds potential to cause TDI. IC50 shift assay does not show whether the TDI is reversible or irreversible, however further studies, e.g. dialysis assay, can be conducted to find it out. If the study compound is irreversibly bound to the enzyme, the enzyme activity should not recover in the dialysis. The aim of this master’s thesis was to develop a dialysis method that could determine the reversibility of the TDI observed in the IC50 shift assay. A dialysis method conducted with microsomes is described in earlier literature. Known inhibitors (both time-dependent and direct) for four CYP isoforms were studied in this work: CYP1A2 (furafylline and fluvoxamine), CYP2C9 (tienilic acid and sulphaphenazole), CYP2D6 (paroxetine and quinidine) and CYP3A4 (verapamil, azamulin and ketoconazole). IC50 shift assays were conducted to each inhibitor before the dialysis experiment. The studied compounds behaved in the dialysis assay mostly as assumed based on the literature. The workflow from IC50 shift assay to dialysis assay worked successfully and the IC50 shift data could be utilized when choosing the test concentrations for dialysis assay. Both the IC50 shift assay and dialysis assay were reproducible and the deviations between replicates and separate studies were relatively low. The method still requires some optimizing, but so far, the results are promising. In the future the dialysis method may be part of in vitro CYP inhibition studies at Orion Pharma.
  • Porola, Pauliina (2012)
    Hepatotoxicity is an undesired feature of many drugs and is one of the main reasons for attrition during the drug development process. Although an in vitro model can never totally correspond to or replace a whole organism, a reliable in vitro model for liver toxicity screening would help to detect liver toxicity earlier in the development process. Effective and early in vitro screening would reduce the need of animal subjects and clinical trials and thus would be both ethically more acceptable and more cost-effective. Currently mostly used models for liver metabolism and toxicity studies are primary hepatocytes, hepatic cell lines and animal models. However, these models have many drawbacks and are not considered reliable. Human embryonic stem cells (hESCs) are pluripotent cells that can be differentiated into many specialized cell types including hepatocytes. They are also self-renewable and thus represent an unlimited and promising source of hepatocytes to be used as a tool in in vitro liver toxicity testing of drug candidates. The aim of this study was to produce hepatocytes from hESCs via multiple steps following the in vivo pathway of developing hepatocytes: first hESCs were differentiated into definitive endoderm cells, after which they were differentiated into hepatic progenitor cells. Finally, hepatocyte-like cells (HLCs) were induced from the progenitor cells. Our specific interest was the use of hepatic cell derived acellular matrix as a differentiation basis for hepatic progenitors and hepatocytes. We also studied the effect of Matrigel overlay on the hepatic differentiation. Differentiation method without the Matrigel overlay was promising. HLCs showed correct hepatocyte-like morphology and expressed hepatocyte markers such as albumin, α-antitrypsin, CYP3A4 and HNF4α both on mRNA and protein level shown by qPCR and flow cytometry and immunofluorescence staining, respectively. Accordingly, the expression of stem cells marker SSEA-3 showed a tendency to decrease as the differentiation proceeded. HLCs also functionally resembled hepatocytes shown by albumin production. However, we could not detect other hepatocyte functions such as urea production or CYP activity. With Matrigel overlay, the hepatocyte-like morphology of the cells was lost, no albumin production was shown and the expression of several hepatocyte markers was lower than in the experiment done without the Matrigel overlay. Thus, Matrigel overlay was shown to be unbeneficial for hepatocyte differentiation. In conclusion, we showed that differentiation of hESCs on the acellular matrix with specific growth factors and without the Matrigel overlay seems promising as a method to produce HLCs. This preliminary study serves as a basis for future studies, in which the differentiation method should still be further studied and developed to yield functional HLCs of uniform quality.
  • Kuisma, Saara (2012)
    Pharmaceutical companies are currently facing increasing developmental costs, and at the same time, less new compounds are being brought to the market. In vitro -metabolism studies and toxicity assessment of new drug candidates are crucial, as early as possible, to prevent their withdrawal in later development phases. Used study systems are, however, limited and new improved technologies are being investigated. Notable, drug induced liver toxicity and alterations in the liver function are frequent reasons for the drug removals from the development. Human embryonic stem cell (hESC) is one of the most powerful cell types known. hESCs have not only the possibility to divide indefinitely but these cells have also the ability to differentiate to all mature cell types of the human body, such as hepatocytes. This makes them potentially very valuable for pharmaceutical development, in order to create a functional in vitro -model, mimicking the liver tissue. In the literature part, the three dimensional (3D) -hepatic differentiation of mouse and human ESCs in vitro, are discussed. Traditional 2D-culture systems do not adequately mimic the microenvironment of three dimensionally organized native tissue. In 2D-cultures cells grow as a monolayer, when the cell morphology is flattened leading to poor cell-cell and cell-matrix contacts and preventing from the tissue formation. In 3D-culture systems, cells are able to form tissue-like cell integrations, spheroids, and thus, remain their functionality and viability significantly longer. Hydrogels are commonly used biomaterials in 3D-cell cultivation and well known in various areas of tissue engineering for their nano scale porosity and ability to surround cells in 3D-polymer network. In addition, they are capable to absorb large volumes of water and functionalized, in various ways, to improve the required biological or mechanical properties. In the experimental part, the main purpose was to differentiate human hepatic progenitor cells to mature hepatocyte-like cells in three dimensional (3D) -biomaterials. Overall, four different hydrogels (cellulose nanofiber (CNF) hydrogel, HydroMatrixTM, ExtracelTM and PuraMatrixTM) were used as 3D-cell culture scaffolds. Several hepatic cell functions (albumin and urea production and cytochrome P450 (CYP) 3A4 activity) were measured in 2D- and 3D-cultures and compared with the human hepatic carcinoma cells, HepG2, which are often used in drug development. Differentiated hepatocyte-like cells did not show CYP3A4 activity and they produced less albumin and urea compared with HepG2 cells. However, working with hESCs is very demanding and the research in this area is only in the beginning. Therefore, the poor cell functionality results did not come up as a surprise.
  • Turunen, Tiina (2016)
    Posterior eye segment diseases, such as age-related macular degeneration, are leading causes of preventable visual impairment in the developed countries. Direct intravitreal injections are currently routinely used to deliver therapeutic agents most efficiently to posterior eye segment. Regular injections can however cause ocular complications and some drugs may also be toxic to ocular tissues at high local concentrations of free drug. Different nano-sized particulate systems have been extensively studied as possible drug delivery systems for intravitreal administration offering sustained, local drug action with controlled release. The vitreous gel can form a barrier for diffusion of particles due to its macromolecular structure and composition. Furthermore, ageing and different disease states cause changes in the vitreous structure possibly resulting in shift in the intravitreal movement of particulate systems. In the literature part of this Master's thesis ocular drug delivery is reviewed with main focus on drug targeting in the posterior eye segment. In the experimental work liposomes with different lipid compositions and surface charges were prepared as model particulate systems to evaluate the intravitreal diffusion of nanoparticles with confocal microscope. Furthermore, the influence of aging on the intravitreal diffusion was modeled by enzymatic degradation of the vitreous gel structure. It is discovered that vitreous gel hinders the movement of nanoparticles. Level of hindrance depends on particle's characteristics. 100-200 nm anionic particles move quite freely in the negatively charged vitreous gel. Similarly sized cationic particles are immobile in the vitreous due to electrostatic interactions between surface of the cationic particle and anionic glycosaminoglycans in the vitreous. 1 µm anionic and cationic particles are sterically trapped inside the vitreous meshwork created by the 3-dimensional biopolymer network of the vitreal macromolecules. Vitreous liquefaction increases the diffusion rate of nanoparticles but the clinical impact on ocular pharmacokinetics needs further research.
  • Veijanen, Terhi (2020)
    Granulation is used to improve the flowability of pharmaceutical powders, reduce the amount of fines and increase the density of the material. Roller compaction has shown growing interest in recent years and it is used ever more frequently in pharmaceutical industry. Roller compaction has many superior qualities compared to wet granulation such as good control of process and absence of moisture and heat in the process. It is also cost effective compared to traditional granulation methods. New APIs are often sensitive to moisture. Therefore traditional granulation methods cannot be used. In the roller compaction process powder mixture is fed between two counter-rotating rolls where the compaction occurs and ribbon is formed. After compaction the ribbon is crushed into granules of desired size. The aim of this study was to find out how the mixture ratio of plastic and brittle material affects the physical properties of roller compacted ribbons such as the strength and stiffness of the ribbons and the structure of the ribbon surface. The materials used were microcrystalline cellulose and dicalsiumphosphate. Nine powder mixtures of 0 to 40 w-% of dicalsiumphosphate were prepared after which the mixtures were roller compacted with the same compactor parameters. Two methods were developed to study the above mentioned characteristics of the ribbons. For the stiffness and strength studies a 3-point bending method was developed for Lloyd material tester. For the surface structure characteristics of ribbons a measurement set up for FlashSizer 3D image analysis device was designed. Bending tests for the ribbons were performed in two different directions. For each batch of ribbons a slope of the linear area and maximum point of bending curves were defined, which represent the stiffness and strength of the ribbons accordingly. Also Young’s modulus and tensile strength were calculated, which are characteristics of a given material. In addition area under curve, which represents the work done to break the ribbon, was calculated. The strength and stiffness of the ribbons decreased with the increasing amount of dicalsiumphosphate. A clear trend was observed. Also Young’s modulus, tensile strength and AUC decreased accordingly. The increase of dicalciumphosphate led to diminished compactibility of the powder mixtures. The compaction force was probably not high enough to fragment the dicalsiumphosphate particles. The ribbons showed higher strength and stiffness when the bending was done perpendicularly ie. across the ribbon width compared to parallel measurements. Also relative standard deviations were smaller in this measurement set up. The 3-point bending method could not mostly distinguish between adjacent formulations from each other but when the difference in the amount of dicalsiumphosphate increased to 10-20 w-% statistically significant differences were observed in most of the calculated values. The surface structure of the ribbons differed between formulations when evaluated visually. Ribbons with less dicalsiumphosphate had a surface structure that followed the knurled pattern of the compactor rolls better.
  • Tuominen, Elsi (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.
  • Nurmi, Satu (2014)
    Many drugs are known to bind to melanin, a complex pigment polymer found in several human tissues. Melanin can act as a natural depot by prolonging the effect of the drug and reducing its toxicity. Since it is highly concentrated in the posterior part of the eye, pigment targeted long-acting drug delivery systems are proposed as an option in ocular diseases. In systemic drug delivery, pigment targeted drugs can potentially distribute to any melanin containing tissue. Therefore, the literature review of the thesis concentrates on the characteristics of melanin and melanosomes, drug binding property and melanin distribution in humans and other species. The main objective of the exploratory part was to determine if melanin binding can be studied with SPECT/CT (single photon emission computed tomography / computed tomography) imaging method. Two different melanin binding drugs, chloroquine and nadolol, were selected and labeled with iodine and radioactive iodine (123I). Equilibrium melanin binding of iodinated and non-iodinated drugs was studied in vitro in order to find out if iodination affects to the binding. Melanin binding was studied in vitro also with non-binding reference salicylic acid, I2-salicylic acid and salbutamol. Finally, melanin binding of 123I-choloroquine and 123I-nadolol was studied with SPECT/CT (NanoSPECT/CT, Bioscan Inc., USA) by comparing distribution kinetics between pigmented and albino rat. Drugs were administered intravenously to the tail vena and the distribution was followed in several time points, up to 24 h. Based on in vitro study, iodination increases melanin binding of hydrophilic drugs, nadolol and salicylic acid, significantly. In vivo study showed clear accumulation of 123I-chloroquine in the posterior eye of pigmented rats whereas it was absent from albino rat. Interestingly, 123I-nadolol accumulated in to the nasal cavity of pigmented rats. Aromatic iodination changes electronegative properties of compounds and raises their logP (octanol/water partition coefficient) value affecting to the melanin binding positively. Therefore the effect of the radiotracer to the physicochemical properties of the compound and melanin binding should be determined in vitro. This study showed that SPECT/CT imaging method can be used to study melanin binding in vivo. Because the method is semi-quantitative, also a quantitative method should be incorporated to the study in order to have more powerful data. Additional studies are required for statistical analysis.
  • Tiainen, Elina (2024)
    New drugs against malaria are required, as millions of people are still affected yearly by this deadly disease. The development of drug resistance to current antimalarials is an ongoing process. Membrane-bound pyrophosphatases (mPPases) are potential new drug targets against malaria and other protozoan diseases. mPPases play a crucial role in the survival of the malaria parasite, they couple the energy released from the hydrolysis of pyrophosphate into the transport of protons or ions against an electrochemical gradient. The aim of this study was to identify potential mPPase inhibitors through a docking-based virtual screen of the Tres Cantos Antimalarial Compound Set, which consists of over 13500 malaria-active compounds. The virtual screen against a Thermotoga maritima mPPase protein structure identified a 2,4-diamino-1,6-dihydrotriazine among the top-ranking scaffolds. Four compounds found among the docking results containing this scaffold were synthesised: three with a halophenyl substituent, and one with a hydroxyl substituent. The compounds in their hydrochloride salt forms were synthesised using a three-component method for the synthesis of 2,4-diamino-1,6-dihydrotriazines. The compounds were also freed from the hydrochloride salts into their corresponding molecular forms. The structural characterisation of the compounds, especially the molecular forms, presented challenges. The docking results were also searched to identify compounds containing previously identified mPPase-active substructures. From the docking results, several other interesting compounds were identified in addition to the synthesised compounds. The knowledge and results obtained from this study can be used as openings for potential future docking and synthesis projects in the development of mPPase inhibitors. The activity of the compounds synthesised in the project remains to be evaluated in subsequent investigations.
  • Saukkonen, Anni (2015)
    Amyotrophic lateral sclerosis (ALS) is a progressive fatal neurodegenerative disease affecting motor neurons. It finally leads to the malfunction of the respiratory muscles and death after 1-3 years of diagnosis. Sporadic cases of ALS cover 90-95% of all patients and familial 5-10% respectively. The onset of the disease is usually between age of 40 and 60 and the worldwide incidence is considered to be 1-2/100000. Currently discovered cerebral dopamine neurotrophic factor, CDNF, has showed neuroprotective effects on Parkinson's disease model. What is more, it is known that CDNF is expressed in the muscles of mice and one of its' main functions is to protect cells from ER-stress, one of the pathological mechanisms in ALS. Hence, it is rational to study the effects of CDNF in ALS mouse model. Treatment options are needed, since there is only one approved treatment for ALS, anti-glutaminergic rilutzole. The aim of this study was to find out whether CDNF shows neuroprotective effects in SOD1-mice e.g. by measuring the changes in motor function with different behavioral tests. More over, the distribution of CDNF after intrathecal ventricle injection was studied using immunohistochemical and radioactive labeling methods. The hypothesis was that CDNF is distributed through the cerebrospinal fluid into the spinal cord and muscles in the limbs and shows neuroprotective effects in this SOD1 mouse model.
  • Montonen, Heidi (2013)
    Literature review: The plasma membrane DA transporter (DAT) belongs to the family of Na+/ClÙÄÉ≠ dependent neurotransmitter transporters. DAT is the primary mechanism for clearance of dopamine from the extracellular space and transporting it back to the presynaptic nerve terminals. There's a great interest in the DAT and its regulation as its substrate, dopamine, mediates a wide array of physiological functions e.g. locomotor activity, cognition and the control of motivated behaviors. With selective transport DAT limits the intensity and the duration of dopaminergic signal. Its function is regulated by several kinases, phosphatase and protein-protein interactions. The altered expression of DAT may be related to several neurological diseases such as Parkinson's disease, addiction and ADHD. To study DAT's function, several genetically modified mouse lines including DAT knockout mice, DAT knockdown mice and DAT knock in mice with elevated DAT levels have been generated. Experimental part: Glial cell line-derived neurotrophic factor (GDNF) plays important role in the survival and function of dopaminergic neurons, learning, memory and synaptic plasticity. More recently, several studies have shown that GDNF can also negatively regulate the actions of abused drugs. The aim of this study was to investigate GDNF's role and mechanism of action in plasticity and function of the dopaminergic neurons projecting to striatum. For that purpose, we used in vivo microdialysis in freely moving mice. We chose two different mouse lines: MEN2B mice with constitutive active Ret-signaling and elevated striatal dopamine concentrations, and GDND-cKO mice that lack GDND in the central nervous system. Microdialysis guide cannula was implanted in the dorsal striatum in the stereotaxic surgery and the mice were allowed to recover for 5-7 days. The concentrations of dopamine and its metabolites DOPAC and HVA and also 5-HIAA were determined from the samples by highperformance liquid chromatography. Microdialysis was performed twice for every mouse on days 1 and 4. Between microdialysis days, the mice were given amphetamine 1 mg/kg i.p. on days 2 and 3. In the microdialysis experiment, the mice received amphetamine stimulation (100 µM/60 min) via microdialysis probe. The placements of microdialysis probes were verified from fixed brain sections after the experiments. Amphetamine increased the dopamine output in both mouse lines, but there were no statistically significant differences in striatal dopamine concentrations between genotypes neither after acute nor chronic administration. However, there was a difference between the dopamine outputs in days 1 and 4 in both MEN2B and GDNF-cKO mice: The striatal dopamine concentrations were significantly lower on the second microdialysis day. This may be a sing from tolerance to the drug. However, without more research, it is not possible, by this experiment, to draw direct conclusions of GDNF's role in addiction and in plasticity in striatum. It is possible that the differences between genotypes are too small to be seen with microdialysis. Development of compensatory mechanisms in mice cannot be ruled out either. Effects may also vary between different brain areas.
  • Kosma, Oona (2016)
    The leading causes of vision loss in developed countries are related to the impairment of the posterior segment of the eye. The drug delivery to the posterior segment with topical or systemic methods is challenging due to the protective barriers of the eye. The conventional and effective technique to deliver therapeutic concentrations of drugs to the posterior segment is intravitreal injection. Since naked molecules usually have a rapid vitreal clearance, the invasive injections need repeated administration in chronic conditions, resulting to increased risk of complications and poor patient compliance. The growing field of research of drug delivery systems, such as implants, nano- and microparticles and liposomes emphasizes to answer these challenges by enhancing time-controlled and targeted drug release to retinal and choroidal tissues, enabling less frequent administration and reduced off-target side effects. Liposomal drug delivery systems have potential in delivering therapeutics to posterior eye tissues in sustained and targeted manner. The experimental part of the thesis focused on studying the cell uptake, content release and cytotoxicity of light triggered pH-sensitive gold nanoparticle liposomes in human retinal pigment epithelial (ARPE-19), human umbilical vein endothelial (HUVEC) and monkey choroidal endothelial (RF/6A) cell lines. To enhance the cell differentiation to resemble the in vivo morphology, ARPE-19 cells were also used as a filter-cultured model. HUVEC cells were cultured on an artificial basement membrane matrix and induced with vascular endothelial growth factor (VEGF) to form capillary like tube structures. The liposomes were not cytotoxic during 24-hour incubation. All cells internalized liposomes to some extent, but in HUVEC capillary tubes the uptake seemed to be negligible. The light induced calcein release was variable between the experiments, possibly due to the study setting related factors, such as difficulties in temperature control. The liposomal carrier system has promising attributes to posterior eye drug delivery. Liposome-encapsulation prolongs the half-live of a drug. Light triggered release and pH-sensitivity enables highly targeted intracellular drug release decreasing the off-target side effects. Optimization of the study arrangement and liposome production procedure is needed in order to get more reliable results and further assess the future potential of these liposomes in the treatment of posterior eye diseases.
  • Hussein, Zahra (2018)
    Drug shortages have become a global issue and reasons for drug shortages are several and multifactorial. Definition of drug shortages is not unambiguous. However, in literature are numerous different suggestions to determine the phenomenon of drug shortages. This study provides more focused information on drug shortages and the reasons behind them. The study was performed in cooperation with Orion Corporation. The aim of this study was to explore the in-depth reasons behind medicine shortages from the perspective of one European pharmaceutical company with special focus on Finland, Germany, the United Kingdom and Sweden. Interviews of the company employees were used to achieve this aim and build a few case studies. Further the aim was to investigate in-depth reasons for drug shortages using data from case studies. Case studies were provided by Orion since this enabled use of unpublished information compare the case studies with relevant legal and regulatory measures in the European pharmaceutical framework which influence drug shortages. Reviewing available data from literature and from EUDRA GMDP database for drug shortages and investigate if the data is detailed enough to understand in-depth reasons for drug shortages. Based on the interview results the most common reasons behind drug shortages in Europe are mainly pharmaceutical market structure 38%. It contains many different factors, such as small stock size, local and foreign manufacturing issues, logistics and distribution issues, changes in demand and regulatory issues. However, the manufacturing (33%) or regulatory (29%) reasons are almost as numerous as pharmaceutical market structure issues. Pharmaceutical market structure issues include most common reasons which are categorized in supply-related and demand-related reasons. According to this study supply-related reasons are more common (73%) than demand-related reasons (27%). Some reasons behind drug shortages overlap and often cause a domino effect, whilst other are unique or stand alone, like reasons resulting from natural disasters. The results of this study seem generalizable because the EUDRA GDMP database shows same results and case studies illustrative same reasons behind drug shortages. This study provides more focused information on drug shortages and the reasons behind them from the perspective of pharmaceutical company and authorities.
  • Ahtola, Martti (2015)
    The goal of the thesis was to optimize a dry powder layering process that would produce a swelling polymer layer that could work as a base layer for another layer. The GPCG 1 (Glatt) fluidized bed granulator was equipped with a rotor. Such hydrophilic polymers were used for coating that would not be sensible timewise for wet coating methods because of long process time. For design of experiments Definitive Screening was chosen because it works in situations where time is limited and there is high number of parameters. There were six parameters, four related to the equipment settings and two related to the formulation, that were tested on three levels. The results were used to get optimized parameters using a model in MODDE software. The quality of the coating was analyzed by measuring the friability (strain test with fluidized bed granulator), particle size (dynamic image analyzer), density (helium pycnometer and mercurity porosimeter), erosion (size exclusion chromatography), loss on drying (halogen moisture analyzer) and coating efficiency (weighing and loss on drying). Coating was also analyzed also with scanning electron microscopy. The process was robust with regards to sphericity of the coated pellets. In SEM pictures none of the coatings showed complete film formation. Friability method did not show significant differences between batches. Coating efficiency was high for all batches. Correlations between product characteristics were analyzed and some correlations were observed between including correlations between LOD/CE and densities. No correlation between the densities measured with two different methods were seen. Some of the settings in the DOE were too extreme and produced batches that were very difficult to analyze. Two more batches were produced with adjusted settings. This affected somewhat the ability to develop a reliable model. Model development were also affected by insufficient results from erosion tests and because coating efficiency results with water was used. Some stability problems were noticed during design of experiments and chosen equipment limited the scale of settings. Coating material adhered to the surface of the pellets and process could be adjusted by changing the parameters of the DOE. Some correlations were noticed between formulation, equipment settings and coating properties.
  • Huovila, Tiina (2017)
    Autophagy is a pathway for cells to degrade intracellular components that are no longer needed or are detrimental for the cells. It is essential for cell homeostasis and survival and has been related to various diseases and pathophysiology. Autophagy is a complex process and there are still several unclear und unknown aspects to it. Regulation of autophagy is essential to prevent unwanted and escess activation, and several pathways and molecules, both stimulatory and inhibitory, are included. Different signaling pathways are sensitive to a variety of environmental clues. Two main autophagy pathways are mTOR-dependent pathway and mTOR-independent pathway. Induction of autophagy in the latter pathway is dependent on the interaction of Bcl-2 and Beclin 1. Prolyl oligopeptidase (PREP) is a peptidase enzyme that has several substrates. PREP-inhibition by KYP-2047 can reduce aggregation of α-synuclein in two ways: by increasing rate of autophagy and by decreasing dimerization. The aim of this study was to find out how PREP affects the interaction between Bcl-2 and Beclin 1 and how this affects autophagy. Based on previous studies, PREP-inhibition seems to increase the amount of Beclin 1 and to affect the phosphorylation of Bcl-2 and Beclin 1, leading to dissociation of the complex. Hypothesis was to see differences in colocalization of Bcl-2 and Beclin 1 in cells treated with different PREP-modifications and for PREP-inhibition to decrease the colocalization. Human embryonic kidney cells 293 (HEK-293) and hPREP knockout cell line created from them by using CRISPR/Cas9-silencing were used in the experiments. Two experiments were performed on regular HEK-cells: inhibitor experiment with KYP-2047 (1 or 10 µM) and overexpression experiment (transfection with either active or inactive hPREP plasmid). After immunofluorescence staining, cells were analysed with confocal microscope and colocation analysis of Bcl-2 and Beclin 1 was performed. The intensity of Beclin 1 in the nuclei was stronger than in other parts of the cell in all samples, which could indicate a stronger activity of its nuclear tasks compared to autophagy. However, the antibody used for immunofluorescence has most likely caused this staining pattern. Based on previous knowledge, it was expected to see differences in colocalization of Bcl-2 and Beclin 1 in cells treated with different PREP-modifications. However, there were no significant differences in colocalization of Beclin 1 and Bcl-2 in any of the experiments but it was nearly 100 percent in all treatments. Since rate of autophagy in cells was not detected, it is impossible to determine, if there were changes in autophagy that were not reflected as changes in colocalization of these two proteins. It is possible that even a small change in colocalization can affect the rate of autophagy or there might be subpopulations where the interaction is interrupted and these changes are so small that they are not detectable with the methods used in this experiment. Both Bcl-2 and Beclin 1 also have functions not related to autophagy, which could be one reason behind the results gained in this study.
  • Partti, Susanna (2014)
    Blood-brain barrier (BBB) is a physical barrier between the blood and the brain. BBB restricts drugs transport from blood stream to the brain, which sets challenges in drug delivery to the brain. Nanoparticles can be utilized in drug delivery to the central nervous system (CNS). Nanoparticles are internalized via endocytosis. However it remains unknown which endocytic pathways are active in brain endothelial cells. The characterization of BBB cells would help light on the exact mechanism of nanoparticle delivery into the brain, which would enable the design of targeted nanoparticles to deliver drugs to the CNS. In present study we characterized human brain endothelial cells, hCMEC/D3, which are widely utilized as BBB in vitro model. As brain endothelial cells are polarized in vivo, the aim of the study was to demonstrate the cell polarization of hCMEC/D3 cells and to study the activity and functionality of different endocytic pathways as a function of cell polarization. The level of cell polarization in cells grown on transwell permeable supports was characterized at multiple timepoints with four different methods: transepithelial electrical resistance (TEER) measurement, lucifer yellow permeability assay, alkaline phosphatase expression and ZO-1 expression. To characterize hCMEC/D3 cells for the presence of specific endocytic pathways, proteins involved into each pathway were selected. Expression of these proteins at mRNA level was assessed by quantitative real-time polymerase chain reaction (qRT-PCR). For clathrin-mediated endocytosis, mRNA level of CHC protein was further correlated with the protein level of this protein, and the activity of clathrin-mediated endocytosis was analyzed by fluorescence activated cell sorting (FACS). Our results showed that hCMEC/D3 cells are best polarized after growing on transwell permeable support for 7 days. At the later timepoints, the cell polarization started to decrease, probably due to multilayer formation. We concluded that measuring TEER alone is not a reliable method to determine polarization status of the cells. mRNA levels of endocytosis-related proteins did not change remarkably as a function of cell polarization. In case of clathrin-mediated endocytosis, there was lack of correlation between CHC mRNA and protein level, but good correlation between mRNA level and activity of the pathway.
  • Kosimov, Yorkin (2016)
    The main goal of this thesis was to examine the effect of the compaction speed on the compressional behaviour of two excipients, microcrystalline cellulose and starch, using an eccentric and rotary presses. First, the average weights of the tablets have changed due to the increasing speed, as the volume of die kept constant. They were grown, for eccentric press, or were reduced, for rotary press. Second, Compression force, needed to obtain tablets with similar strength, was increased during both tableting methods. The eccentric compaction was more stable regarding to the speed increase. Tablets were formed from all of the blends, with more or less success. Additionally, as a result of force increase, resulted tablets were denser and less porous because of speed expansions during eccentric press. However, the blends containing 80% or more starch were not able to form tablets during the rotary press, because of the very poor die filling. Furthermore, blend containing 60% starch has shown very poor tabletability at speeds over 34 rounds per minute. The elastic recovery of tablets was very sensitive to the speed rises and to the concentrations of excipients during the eccentric press. Tablets have demonstrated an increase in their elastic recovery values in all cases. However, the tablets with a higher concentrations of starch were significantly more sensitive to the increasing compaction velocity. According to these results, it can be concluded that the starch exhibit more elasticity than microcrystalline cellulose. The effect of magnesium stearate on tablets' properties, such as the weight and the porosity, and compaction parameters, such as ejection force have also examined. As it expected from boundary lubricants, magnesium stearate has significantly reduced the ejection force values, required for removing the tablet from the die, compared with unlubricated tablets. Additionally, tablets with lubricants were heavier and more porous. The compression force was adjusted according to the crushing strength values in rotary press. This was due to the fracture variations of such tablets during diametrical compression, which would give unreliable values of tensile strength. Moreover, elastic recovery, porosity, density values were not calculated for scored tablet, due to either the lack of punch displacement data from rotational machine or the relative complexity of measuring the volume of such tablets. If these values had been available for both machines, their comparison with respect to these parameters would be possible and the results of this thesis would have been more appropriate.
  • Autio, Maiju (2011)
    Generation of raw materials for dry powder inhalers by different size reduction methods can be expected to influence physical and chemical properties of the powders. This can cause differences in particle size, size distribution, shape, crystalline properties, surface texture and energy. These physical properties of powders influence the behaviour of particles before and after inhalation. Materials with an amorphous surface have different surface energy compared to materials with crystalline surface. This can affect the adhesion and cohesion of particles. Changes in the surface nature of the drug particles results in a change in product performance. By stabilization of the raw materials the amorphous surfaces are converted into crystalline surfaces. The primary aim of the study was to investigate the influence of the surface properties of the inhalation particles on the quality of the product. The quality of the inhalation product is evaluated by measuring the fine particle dose (FPD). FDP is the total dose of particles with aerodynamic diameters smaller than 5,0 µm. The secondary aim of this study was to achieve the target level of the FPD and the stability of the FPD. This study was also used to evaluate the importance of the stabilization of the inhalation powders. The study included manufacturing and analysing drug substance 200 µg/dose inhalation powder batches using non-stabilized or stabilized raw materials. The inhaler formulation consisted of micronized drug substance, lactose <100µm and micronized lactose <10µm. The inhaler device was Easyhaler®. Stabilization of the raw materials was done in different relative humidity, temperature and time. Surface properties of the raw materials were studied by dynamic vapour sorption, scanning electron microscopy and three-point nitrogen adsorption technique. Particle size was studied by laser diffraction particle size analyzer. Aerodynamic particle size distribution from inhalers was measured by new generation impactor. Stabilization of all three raw materials was successful. A clear difference between nonstabilized and stabilized raw materials was achieved for drug substance and lactose <10µm. However for lactose <100µm the difference wasn't as clear as wanted. The surface of the non-stabilized drug substance was more irregular and the particles had more roughness on the surface compared to the stabilized drug substances particles surface. The surface of the stabilized drug particles was more regular and smoother than non-stabilized. Even though a good difference between stabilized and non-stabilized raw materials was achieved, a clear evidence of the effect of the surface properties of the inhalation particles on the quality of the product was not observed. Stabilization of the raw materials didn't lead to a higher FPD. Possible explanations for the unexpected result might be too rough conditions in the stabilization of the drug substance or smaller than wanted difference in the degree of stabilization of the main component of the product <100µm. Despite positive effects on the quality of the product were not seen there appears to be some evidence that stabilized drug substance results in smaller particle size of dry powder inhalers.
  • Stenberg, Emilia (2023)
    Drug transporters and metabolizing enzymes have an important role in drug absorption in the small intestine. Food-drug interactions can affect the function of drug transporters and metabolizing enzymes in the small intestine and hence the bioavailability of drugs may change. Certain beverages have clinically relevant interactions with drugs and drinking of them should be avoided during certain drug treatments. However, possible food-drug interactions need more in vitro and in vivo studies, for example in the case of food additives which are used in the food industry increasingly, to investigate their clinical significance as inhibitors. Overall, investigating food-drug interactions is important as they might be as relevant as drug-drug interactions, especially for drugs that pass the gut wall mainly via transporters or have high presystemic metabolism. In this thesis, the inhibitor potential of 23 food additives was studied toward intestinal transporters and CYP enzymes. The food additives included sweeteners, colorants, and antioxidants. Food additives were tested against four efflux transporters with vesicle transporter assays and in OATP2B1 influx transporter with HEK293 uptake assay. The inhibition of CYP enzymes was tested in human intestinal microsomes. Six food additives were identified as possible inhibitors of BCRP, MRP2, OATP2B1, or P-gp. Two food additives were dual inhibitors. IC50 values were determined in dose-response studies for the potential inhibitors. The IC50 values were compared to the maximum expected concentration in the intestinal lumen to evaluate if the in vivo inhibition of intestinal transporters is possible. Only one food additive had a higher IC50 value than the maximum expected concentration. Eight food additives, specifically six antioxidants and two colorants, inhibited CYP-enzyme metabolism by more than 50%. Based on the results of this thesis, further studies could be performed for the identified inhibitors whose daily consumption is higher than the IC50 value. Certain food additives may inhibit CYP enzymes and the microsome assay used in this thesis is valid and could be used to study the metabolism of intestinal drug-metabolizing enzymes. However, the inhibition of transporters and CYP enzymes could be tested in cell lines, for example Caco-2 cells, to have more realistic intestinal test conditions.
  • Kullbäck, Jonas (2024)
    Congenital heart diseases develop during heart development and encompass structural abnormalities in the heart present at birth, with hypoplastic left heart syndrome (HLHS) representing a rare but life-threatening subtype. HLHS is characterised by the underdevelopment of left-sided heart structures, resulting in a major blood flow obstruction of the heart, impairing systemic circulation. Current knowledge of HLHS aetiology is scarce, which makes the development of effective treatments challenging. Therefore, identifying the disease mechanisms causing HLHS is essential. Notably, HLHS is linked with mutations in the NKX2-5 gene, which encodes for a cardiac transcription factor and has a pivotal role in heart development together with the transcription factor GATA4. This makes these genes intriguing research targets in HLHS. This study aims to enlighten how HLHS patient-derived human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) differ from those derived from healthy donors in terms of stress response by subjecting hiPSC-CMs to pro-hypertrophic stimuli, namely endothelin-1 (ET-1) and cyclic mechanical stretching. Additionally, the effects of GATA4-targeted compounds on these hypertrophy models were also studied, which included two inhibitors (3i-1262 and 3i-1000) and one activator (3i-0777) of GATA4-NKX2-5 interaction. Differentiation of CMs was performed using a small-molecule induction protocol based on sequential Wnt pathway activation and inhibition. The effects of ET-1 and cyclic mechanical stretching were analysed by High-content analysis for pro-B-type natriuretic peptide (proBNP) expression, and quantitative PCR for hypertrophic gene expression, respectively. Both ET-1 and cyclic mechanical stretching effectively induced hypertrophy in their respective models. This was observed in all cell lines as a higher hypertrophic response of proBNP in ET-1 exposed hiPSC-CMs and upregulation of hypertrophic genes NPPA and NPPB in stretched hiPSC-CMs. GATA4-targeted compounds did not show statistically significant effects on ET-1-induced hypertrophy or stretching-induced hypertrophic gene expression in any cell line, but various trends could be distinguished. As expected, both inhibitor compounds, 3i-1262 and 3i-1000, showed a tendency for antihypertrophic effects since they decreased the percentage of proBNP+ cells in all cell lines. Unexpectedly, the activator compound 3i-0777 also decreased the percentage of proBNP+ cells. We also observed that HLHS-disease cell line HEL 149 seemed to differ from the three other cell lines showing a phenotype that exhibits similar gene expression patterns as seen in heart failure patients. This was mainly observed as a statistically significantly lower basal MYH6 gene expression. However, the limited experimental setup of this study requires further experiments to detect significant differences and draw definitive conclusions regarding the effects of GATA4-targeted compounds on hypertrophic stimuli.
  • Harju, Lauri (2023)
    In pharmaceutical sciences the pharmaceutical supply chain is often examined from a quality perspective. As the world is becoming more uncertain due to pandemics and conflicts the societal and political situation where the supply chain operates should be considered. Understanding the big picture helps to consider the cause and effect that lead to medicinal shortages. Effects of these shortages can be seen on every level of the supply chain from the manufacturer to the patient, which is why actors on the supply chain can benefit from understanding the background factors. The aim of the master’s thesis was to examine, whether pharmaceutical field actors could affect realisation of geopolitical risks by preparation and examination that the pharmacotherapy would not be interrupted. Second aim was to bring forward political and societal aspects to pharmaceutical availability which are often side-lined by quality aspects in pharmaceutical context. The study was conducted as a qualitative semi-structured interview between October 2022 and February 2023. Participants (n=11) were recruited via e-mail using representative sampling. Due to recruitment problems, convenience sampling was also used. Questions presented to the interviewees were depending on the group (n=3) they were assigned. Term ”geopolitics” was associated mainly with political and economic factors. Main geopolitical risks for Finland were seen to be small market size and distant location. For Europe, the risks were centralisation of manufacturing (and dependence) to Asia due to economic factors and long disruption-prone supply chain. Transport of pharmaceuticals from Asia to Europe was with sea and air cargo. Inside Europe, transport to Finland was with mainly with lorries utilising ferries. Rail transport was mentioned to be used only on one interview. The transport routes were seen to be staying the same in the future both for Asia-Europe and Europe-Finland. Even though risk management is an important part of functioning of every company, the change in the type of risks requires a new mindset in the pharmaceutical field both from the individual actors as well as international organisations. From risk of strikes and natural disasters we have moved to trade wars, pandemic restrictions, and the strategic acting of industries critical to society. At the same time, the ability/willingness of societies to pay for pharmaceuticals is decreasing, which leads to the manufacturers to find new ways to ensure business.