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Left ventricular hypertrophy (LVH) is defined as an increase in left ventricular mass. It is initially a coping mechanism by which the heart tries to compensate for the increase in load caused by, for example, hypertension, but it will eventually lead to heart failure. LVH is the result of primarily an increase in cardiac myocyte size, in addition to increased apoptosis and necrosis of cardiac myocytes and fibrosis. Current treatment of LVH is based on a treatment of suspected cause, generally hypertension. Antihypertensive medication has been found to have beneficial effects on LVH. However, antihypertensive drugs can not cure LVH completely, hence other treatment options are needed. To identify new possible drug targets, it is important to increase the inadequate knowledge of the mechanisms and signal transduction pathways mediating LVH. The most relevant stimuli causing hypertrophy are considered to be mechanical stretch, as well as some humoral mediators such as angiotensin II and endothelin 1 (ET-1), to which cardiomyocytes respond through activation of several intracellular signal transduction pathways. As a result, cardiomyocyte gene expression and protein synthesis increase and sarcomeres grow and rearrange, resulting in an increase in cell size. In addition, regulation of calcium, contractile function and energy metabolism of cardiac myocytes change. Numerous intracellular signal mediators interact with each other and can compensate for each other, making it difficult to investigate the significance of individual factors. As important signal mediators are considered to include protein kinase C (PKC) and cardiac transcription factors GATA4 and NKX2-5. In vitro studies of cardiac hypertrophy are usually performed with primary cardiac myocytes isolated from the ventricles of neonatal rats. The H9c2 continuous cell line has been used in some studies as an alternative cell model to reduce the use of laboratory animals. In the experimental part of this thesis, the suitability of H9c2 cells for hypertrophy studies was examined by comparing them to primary cardiac myocytes. In addition, experimental compounds targeted to cardiac transcription factors and PKC were studied by exploring their effects on viability and hypertrophic responses of H9c2 cells and primary cardiac myocytes. The toxicity of the compounds and the effects on cell viability were studied using the lactate dehydrogenase (LDH) assay and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The hypertrophy responses to cyclic mechanical stretch and ET-1 were primarily assessed by measuring the surface area of cells from fluorescence microscopy images. In addition, the relative expression levels of Nppa and Nppb genes in ET-1 stimulated primary cardiac myocytes were studied by quantitative polymerase chain reaction (qPCR). Both stretching and ET-1 caused an increase in the cell surface area in primary cardiac myocytes but not in H9c2 cells. On this basis, the H9c2 cells respond differently to hypertrophic stimuli than primary cardiac myocytes, and the suitability of H9c2 cell line to hypertrophy studies can therefore be questioned. The compounds targeted to cardiac transcription factors were not cytotoxic at 1-30 µM concentrations, but they also had no significant effect on the hypertrophic responses. In contrast, the PKC compound HMI-1a3 at 30 µM was toxic to primary cardiac myocytes and HMI-1b11 at 30 µM was toxic to H9c2 cells. HMI-1b11 and bryostatin-1 also induced changes in the hypertrophic responses of primary cardiac myocytes, but the significance of these results requires further investigation.

Orexins (hypocretins) are two neuropeptides, orexin-A (OX-A) and orexin-B (OX-B), produced by a neuron subpopulation in the mammalian hypothalamus. They are natural substrates of two G-protein-coupled receptors (GPCRs), orexin receptor 1 (OX1R) and orexin receptor 2 (OX2R), respectively. Orexin receptors are expressed widely in the central nervous system. Orexin peptides and receptors were originally discovered in 1998 and have been extensively researched ever since. Maintaining a steady state of wakefulness has been identified as one main physiological function of orexinergic signalling, and loss of orexinergic neurons in the hypothalamus has been linked to narcolepsy. Over the past decade orexin receptor antagonists have been developed for treatment of insomnia – suvorexant as the first one, approved for clinical use in 2014. Orexin receptor agonists remain under development for treatment of narcolepsy as one potential therapeutical indication, with no clinical applications yet approved. Orexin receptor activation by small-molecule agonists has proven a challenge not yet conclusively resolved. The aim of this study was to validate a novel scaffold for orexin receptor agonists from compounds identified as orexin receptor agonists in previous studies. Total of ten compounds were designed for synthesis, three of which were successfully synthesized. These three compounds exhibited very low orexinergic activity (0.06–1.36% and 2.33–5.19% response of full activation for OX1R and OX2R, respectively). After activity testing retrospective modelling of the receptor binding of the synthesized and designed compounds was implemented computationally by structure-based molecular docking to the recently discovered (2021) crystal structure of OX2R in complex with bound small-molecule agonist 3′-(N-(3-(2-(2-(2H-1,2,3-triazol-2-yl)benzamido)ethyl)phenyl)sulfamoyl)-4′-methoxy-N,N-dimethyl-[1,1′-biphenyl]-3-carboxamide. Some of the key interactions known as crucial for receptor activation, such as hydrogen bonds with glutamine Q1343.32, were found possible for some of the synthesized and designed compounds. This may in part explain the orexinergic activity, however very low, measured for the synthesized compounds. Low activity of the synthesized compounds may be a result of low binding since their binding was not tested in this study. Interactions between the synthesized compounds and OX2R predicted by molecular modelling are consistent with the low measured activity of the compounds, and alternative, more optimal chemical scaffolds for orexin receptor activation could be searched in future studies.

Prolyl oligopeptidase (PREP) is a serine protease that is widely found throughout the human body and especially in the brain. The primary function of PREP is thought to be the hydrolysis of the carboxyl side bond of proline residues in oligopeptides. PREP is also shown to increase the dimerization and aggregation of α-synuclein and downregulate the protein phosphatase 2A mediated autophagy in the cell via direct protein-protein interactions (PPI). The accumulation of α-synuclein aggregates in cell is known to cause α-synucleinopathies such as Parkinson’s disease. This makes the PPIs of PREP an attractive target for drug research. The mechanisms of the PPIs of PREP are still poorly understood. Recent studies have shown that these PPIs can be modulated with ligands lacking high inhibitory activity for the proteolytic activity. These studies show that the IC50-value of the ligand does not correlate with ligands ability to affect the PPIs of PREP. Ligands that could selectively modulate the PPIs of PREP without inhibiting the proteolytic activity of PREP could give valuable information on the mechanisms of the PPIs and on how to modulate them. It is hypothesized that the ligands could bind to PREP at a site that does not interfere with its proteolytic activity, and ligand binding is assumed to restrict the dynamic structure of PREP and thereby also modulating the PPIs of PREP. The aim of this study was to synthetize novel peptidic PREP ligands and study their effects on the proteolytic activity of PREP and the PPIs of PREP. The aim was to find and identify ligands and structures that would modulate the PPIs of PREP and observe how the IC50-values of the ligands would correlate. L-Alanyl-pyrrolidine was selected as the scaffold for the compound series and the five-membered heteroaromatics, imidazole, triazole and tetrazole, were added to the 2-position of the pyrrolidine ring. In this position there is an electrophilic group in many PREP inhibitors, although these heteroaromatics are not electrophiles. The scaffold was also expanded by adding phenyalkyl groups with different linker lengths were added to the N-terminal side of the alanine. The ligands were synthesized using four synthesis routes which were based on synthesis methods found in literature. The IC50-values and the effects on α-synuclein dimerization and autophagic flux were determined for five synthetized compounds. The tested compounds were all weak PREP inhibitors and showed no strong activity in the α-synuclein dimerization and autophagy assays. Despite the weak activities in the assays, the importance of the linker length in the phenyalkyl group was shown. Changing the linker by one methylene group had noticeable effect on the overall activity. The results also demonstrate a lack of correlation between the IC50-values and the effects on α-synuclein dimerization and autophagic flux, which further confirms the lack of correlation between the proteolytic function and the PPIs of PREP which was observed also in previous studies.

The human tissue kallikreins (KLKs) form a family of 15 closely related serine proteases (KLK1-15). KLK3 is better known as prostate specific antigen (PSA) and it is highly prostate-specific. Kallikreins are attracting increased attention due to their role as biomarkers for screening, diagnosis, and monitoring of various cancers. Although PSA is a very useful marker for prostate cancer in the blood, the expression level of PSA is higher in normal prostatic epithelium than in tumour tissue, and it is further reduced in poorly differentiated tumours. It has been postulated that PSA activators (stimulating compounds) could be beneficial for patients with prostate cancer. The development of peptides as clinically useful drugs is greatly limited by their poor in vivo stability and low bioavailability. As the problems in using peptides as drugs are mainly arising from the peptide backbone, the focus for synthesizing peptide mimicking compounds is on the peptide backbone and how to replace it. The aim of this work was to replace the central disulfide bridge in the most potent PSA activating peptide C-4 by a hydrocarbon linker that had been previously synthesized in the research group. Two strategies for synthesis of the pseudopeptides were applied: a) synthesis of all peptide bonds on solid support by tailoring the reactions for this particular peptide, and b) synthesis of a monocyclic pseudopeptide in solution that could be incorporated directly into the standard protocol of solid phase peptide synthesis. The first strategy (a) proved to be tedious and would have required a lot of optimization to be successful. The cleavage conditions of the orthogonal protecting groups were not directly compatible with synthesis on solid support. The second strategy (b) also proved to be tedious, epimerization at the histidine residue was very prone in the solution phase even with standard peptide coupling reagents. However, the possibility to monitor all steps of the synthesis and to purify intermediate products made this synthetic route more attractive for this type of pseudopetide. The work in this master thesis resulted in a useful strategy to synthesise the desired pseudopeptides.

Biologiset lääkkeet ovat keskeinen osa syöpäsairauksien hoitoa. Ne ovat usein perinteisiä pienimolekyylisiä lääkkeitä kalliimpia, ja niiden aiheuttamia kustannuksia potilaalle ja yhteiskunnalle voidaan hillitä edullisempien biosimilaarien eli vertailukelpoisten biologisten lääkkeiden käytöllä. Tutkimuksen tavoitteena oli tutkia kyselyaineiston perusteella syöpäpotilaiden näkemyksiä lääkärin toteuttamasta biologisten lääkkeiden lääkevaihdosta ja niihin vaikuttavia tekijöitä avoterveydenhuollossa. Lisäksi tutkittiin, miten yleisesti syöpäpotilaat tunnistavat biologisen lääkkeen ja biosimilaarin käsitteet, ja potilaiden syöpälääkitystään koskevia lääketiedon lähteitä. Tutkimuksen osana toteutettiin järjestelmälliseen kirjallisuushakuun perustuva katsaus syöpäpotilaiden näkemyksistä biologisista lääkkeistä ja/tai biosimilaareista ja niiden lääkevaihdosta. Tutkimus perustui Yliopiston Apteekin ja Helsingin yliopiston yhteistyössä Suomen Syöpäpotilaat ry:n kanssa toteuttamaan tutkimuskyselyyn syöpäpotilaille tammikuussa 2021. Tutkimuskutsu lähetettiin Yliopiston Apteekin kanta-asiakkaille tutkimusuutiskirjeenä ja Suomen Syöpäpotilaat ry tiedotti tutkimuksesta sähköisessä viestinnässään. Tutkimuksen kohderyhmänä olivat aikuiset, joilla oli lääkärin toteama syöpäsairaus ja jotka olivat käyttäneet syöpäsairautensa hoitoon lääkärin määräämä lääkehoitoa kyselyä edeltävän 12 kuukauden aikana. Tutkimusaineisto koostui 294 kohderyhmän potilaasta. Ensisijaisella tulosmuuttujalla (summamuuttuja) tutkittiin syöpäpotilaiden näkemyksiä lääkärin toteuttamasta biologisten lääkkeiden lääkevaihdosta. Vastaajilla oli keskimäärin myönteinen näkemys lääkärin toteuttamasta biologisten lääkkeiden lääkevaihdosta, mutta lääkevaihdon toteuttamiseen liittyi potilaiden kokemaa epävarmuutta (summamuuttuja: Cronbachin alfa 0,808; keskiarvo 3,29/5,00, 95 % lv 3,20–3,38). Myönteinen näkemys oli yhteydessä potilaiden myönteisiin näkemyksiin biosimilaarien ja geneeristen lääkkeiden ominaisuuksista, kuten tehosta, haittavaikutuksista ja käytettävyydestä sekä vastaajan korkeampaan koulutustasoon ja vähäisempiin huoliin yleisesti omasta lääkehoidostaan. Enemmistö (72 %) vastaajista tunnisti biologisen lääkkeen käsitteen, biosimilaari-käsite tunnistettiin heikommin (19 %). Vastaajien käytetyimmät lääketiedon lähteet syöpälääkityksestään olivat terveydenhuollon ammattilaiset (48–88 %) ja pakkausseloste (80 %). Syöpäpotilaiden näkemyksiin biologisten lääkkeiden lääkärin toteuttamasta lääkevaihdosta vaikuttivat useat tekijät, kuten näkemykset biosimilaarien ja geneeristen lääkkeiden ominaisuuksista. Vaikka useat syöpäpotilaat suhtautuivat keskimäärin myönteisesti lääkärin toteuttamaan biologisten lääkkeiden lääkevaihtoon, siihen liittyi usein epävarmuutta. Tulevaisuudessa tulisi tutkia tarkemmin syöpäpotilaiden tietämystä biologisista lääkkeistä ja biosimilaareista. Lisäksi tulisi tutkia millaista lääkeinformaatiota potilaat tarvitsevat päätöksenteon tueksi biologisten lääkkeiden lääkevaihdossa.

Inhibition of the cytochrome P450 enzymes is one of the most significant factors causing drug-drug-interactions, and thus one of the most important objects of study at preclinical drug development. CYP-inhibition can be either reversible or irreversible. Although different inhibition mechanisms are well known, their evaluation in vitro is still challenging. Thus, the development of more accurate and efficient in vitro methods is important and as a continuous target of interest. Immobilized enzyme microreactors (IMER) have presumably several advantages over traditional in vitro methods and have been presented as a promising tool for drug metabolism studies in vitro. The purpose of this work was to evaluate the suitability of a novel flow-through based immobilized enzyme microreactor in determining the CYP enzyme kinetic parameters. The developed immobilization protocol is based on attaching biotinylated human liver microsomes to a thiolene-based microreactor coated with Streptavidin. To validate the developed method, the activity of the CYP2C9 enzyme was assessed using the recommended model reaction by authorities, that is 4-hydroxylation of diclofenac. The enzyme kinetic parameters i.e., enzyme affinity (Km) and activity (Vmax), determined with the developed IMER were comparable to the values previously published in the literature and determined in static in vitro conditions. In addition, the inhibition of CYP2C9 enzyme by four model inhibitors (fluconazole, nicardipine, sulfaphenazole and miconazole), was examined by determining the IC50 (half-maximal inhibitory constant) values for each compound and by monitoring the reversibility of the CYP2C9 enzyme for 90 minutes after the inhibitor was removed from the feed solution. The IC50 values determined with the developed method for all inhibitors were well in line with previous publications, showing fluconazole (IC50 22 µM) to be the weakest inhibitor of CYP2C9 enzyme and the other examined inhibitors caused more potent inhibition (IC50 for sulfaphenazole 1.3 µM; IC50 for miconazole 1.3 µM; IC50 for nicardipine 0.67-1.1 µM). The reversibility of the CYP2C9 enzyme was examined by removing the inhibitor from the feed solution and monitoring the recovery of the enzyme activity via diclofenac 4-hydroxylation. Based on the results obtained with developed IMER, the inhibition of fluconazole and sulfaphenazole was reversible and thus well in line with previous studies. In contrast, on account of data obtained with IMER, inhibition by miconazole and nicardipine was not reversible, although these compounds have previously been reported to be reversible CYP2C9 inhibitors in vitro, which may be due to the strong aggregation tendency of these compounds. The study shows that the developed flow-through based IMER is well suited for studying inhibition of CYP enzymes However, to utilize the developed technology in CYP enzyme inhibition research, it’s applicability in determining enzyme inhibition should still be evaluated with more comprehensively with several CYP isoenzymes.

Automated dose dispensing is an increasing field in which medicines are packaged mechanically into small one-dose pouches in portions of two weeks. Suitability of tablets for automated dose dispensing has not been researched systematically earlier. The study was made in collaboration with the dose dispensing unit of Espoonlahti pharmacy. The aim of the study was to define optimal characteristics for an automatically dispensed tablet from a viewpoint of the dose dispensing process to reduce breakings and transitions. Breaking means that tablet crumbles, splits up or breaks up otherwise during mechanical dose dispensing process. Transition means that tablet is dispensed in a wrong dose pouch. Percentually breakings and transitions occur very little, but quantitatively plenty and increasingly when automated dose dispensing is becoming more common. Breakings and transitions cause plenty extra work because of correcting pouches, so their amount should be aimed to reduce. In addition, the aim is to find out matters to enquire from the manufacturers of medicines that would help concluding whether a product is suitable for automated dose dispensing based on written information. Results of the study indicate that to reduce breakings and transitions, an optimal tablet product for dose dispensing is rather small or middle sized, coated, strong and without a breakline and the optimal relative humidity of air in the product room of dose dispensing unit would be around 30 - 40 %. Matters to enquire from the manufacturers of medicines besides size, coating, breaking strength and breakline are stability of the product outside of its original package and light, heat and moisture sensitiveness of the product. Besides breakings and transitions, also stability of a moisture sensitive acetylsalicylic acid product (Disperin 100 mg) was investigated in 25 °C/60 % RH because air humidity in the product room is not adjustable. Duration of the test was four weeks. It is enough since it is the maximum time that tablets are outside their original packages during drug dispensing process before use. Tablets were kept in opened original container (bottle), in closed original container, in cassette of dispensing machine and in two different dose pouches (new material and the one in use). According to the results, cassettes are protecting tablets from moisture as poorly as an opened bottle. Instead, new pouch material protects tablets better than the material in use. Results of Raman spectroscopy measurements indicate no change in acetylsalicylic acid to salicylic acid during four weeks test. Moisture affects to tablets by decreasing breaking strength, which may cause more breakings. Air humidity should be adjusted in product rooms or tablets should be unpacked into cassettes as near operating the machine as possible to prevent breakings. Especially when air humidity is high. Among others, a heat sensitive drug product was researched because of the seaming unit of dose dispensing machine which is radiating heat of about 75 °C to pouches if machine is pulled over in the middle of work. Study was performed with variable temperature XRPD. Results of the study of heat sensitiveness indicate that 75 °C for 60 minutes doesn't induce changes in carbamazepine tablet (Neurotol 200 mg). However, results of the study reveal that researched product did not contain the most heat sensitive form of carbamazepine, so other heat sensitive drug products should be examined to get more information about effects of heat.

3D-imaging is based on combining two or more pictures to form one three-dimensional picture. Most of the methods used provide only surface pictures, but tomography acquires also information about the inside-structure of investigated material. Young's modulus is a method, which has been used for long time to determine toughness hard materials, such as steal. In traditional method a beam-shaped piece is bent. When the size of piece, used force and amount of bending are known, Young's modulus of piece can be calculated. Although the method has traditionally been used to research very hard materials, it has been applied without changes with pharmaceutical materials. It is, however, open to the question whether or not the method is appropriate for those materials. There are also methods to determine Young's modulus based on compressing a tablet or using ultrasound. Determining tablet's toughness with ultimate strength test is complicated because it breaks tablet. For that reason it would be good to find compensatory methods to measure strength of tablet. The aim of the study was to validate Flash Sizer 3D appliance, which is used in 3D-imiging. Another goal was to investigate possible correlations between 3D-imiging, Young's modulus and traditional ultimate strength method. Lastly, the feasibility of Young's modulus as a substitute for traditional ultimate strength measurement in self life studies was investigated. Flash Sizer 3D was validated by measuring particle size distribution of pellets, which were made of microcrystalline cellulose (Cellets). Sizes of the investigated pellets were 100 µm, 200 µm and 500 µm. Also binary mixture of 100 µm and 200 µm was investigated. From microcrystalline cellulose was made tablets and 3D-pictures were taken. Ultimate strength test was made for half of the tablets. Young's modulus was measured from half of the tablets in tableting day, day after that and nine days after tableting. Results show that Flash Sizer 3D is suitable for investigating bigger Cellet. With smaller particles distinguishing of tablets wasn't probably good enough. Still it seems to be quite good method to determine surface roughness of tablet. Young's modulus seems to be very promising as compensating method for traditional ultimate strength measurement. In future in self life studies tablets hardness might be able to investigate by measuring Young's modulus and not measuring ultimate strength. If correlation between Young's modulus and solubility meets the case, Young's modulus might also replace also solubility measurements in self life studies.

It was given a task to the Finnish Medicines Agency (Fimea) to prepare a national Medicines Information Strategy. The strategy process can be divided into four stages: 1) the collection and analysis of the information, 2) the determination of the strategy and the vision, 3) the realization and 4) the follow-up stage of the strategy. In the European Union (EU) the High Level Pharmaceutical Forum has drawn up the criteria for the high quality medicines information (MI) and the recommendations to improve the quality and availability of the MI directed to the consumers. The most significant medicines related political actions in Finland in the 21st century are the Medicine policy 2010 -document, the strategies of the National Agency for Medicines and the TIPPA-project. The objective of the Master's thesis was to produce the information to Fimea's MI work. The electric questionnaire was drawn up in the Ministry of Social Affairs and Health. After a pilot test, the questionnaire was sent by email to all national Medicines Authorities in EU (n=27) in November 2009. The purpose of the questionnaire was to find out 1) the significance of the medicine information in the national legislation, 2) the possible MI strategies and 3) the control mechanisms of the medicine information directed to the consumers. The medicines information strategies were found in the United Kingdom (UK), Italy and Germany. Furthermore, the strategy process was unfinished in four countries. In the strategy of the UK 25 concrete actions were presented during a three-year strategy period to improve the quality and availability of the MI and to improve the cooperation between public and private actors. The information and communication technology (ICT) was in the centre of the medicines information offered to the consumers. ICT was utilised by publishing Patient Information Leaflets in Internet and by developing medicines information web pages, digitally patient counseling services and quality certificates. The results of the survey can be utilised as a part of the Fimea's Medicines Information Strategy process. Further studies, for example an analysis of the interest groups, are needed before the preparation of the national strategy. Furthermore, experiences of the implementation of the strategy and the results reached in the UK should be clarified.

Long-term use of benzodiazepines is not recommended in the aged. Elimination of these drugs is delayed in the aged, which can prolong drug action and expose users to adverse effects. Long-term benzodiazepine use is associated with many adverse effects, including cognitive impairment and falls. However, there are only few published studies dealing with associations between benzodiazepine concentration and clinical outcomes in the aged in long-term use. The aim of this study was to explore association of residual concentration of temazepam, oxazepam and zopiclone with age, gender, kidney function, drug dose and clinical outcomes, such as self-perceived health and functional abilities in aged patients. The data were collected in Pori City Hospital in July 2004. The patients were between 60-98 years of age (median 81) and the majority (79%) of them were women. Residual drug concentrations were analysed from serum from patients using temazepam (n=14), oxazepam (n=11) or zopiclone (n=28) regularly. Residual oxazepam concentration correlated positively with evening dose (p<0.001) and daily dose (p=0.003). Also oxazepam concentration was higher (p=0.017) in patients who took the last dose later (21:00-02:45) compared to patients with earlier dosing time (15:35-19:00). There was no such association between temazepam or zopiclone and dose or dosing time. This might be explained by the fact that there was more dispersion in the dose and dosing time of oxazepam compared to temazepam and zopiclone. There were no other associations between drug concentrations and demographic variables studied. Concerning associations with clinical outcomes, zopiclone concentration tended to be higher in patients who often felt themselves tired during daytime (p=0.087). Surprisingly, residual serum concentration of oxazepam seemed to be higher in patients who were able to walk and manage their shopping independently. Apart from these findings, residual concentration of temazepam, oxazepam and zopiclone associated poorly with clinical outcomes. These findings do not support routine monitoring of residual benzodiazepine concentrations in aged patients.