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Appetite regulation is a complex process involving regulation of energy homeostasis and the rewarding nature of food. Abnormalities in appetite regulation lead to obesity and eating disorders which are challenging to treat with medicines. Especially obesity is an increasing public health problem and drug development against it is a current subject in research. Hypothalamus is the most important brain area related to appetite regulation. Also, the basal forebrain and the amygdala which are part of the reward system in the brain, contribute to the appetite regulation. There is cholinergic innervation from the basal forebrain to the amygdala and most of the cholinergic activity in the amygdala is originating from the basal forebrain. It is known that the cholinergic system inhibits appetite but there is still no research about impact of cholinergic projections between these two brain areas. Aim of this study was to find out if the cholinergic projections from the basal forebrain to the amygdala effect on appetite regulation. The study included two stereotactic surgery. In the first surgery the mice (n=14) received injections to the basal forebrain that contained genetic materials for DREADDs in AAV. DREADDs appeared in the cholinergic cells of the basal forebrain and emanated within their axons to the amygdala. In the second surgery cannulas were placed to the amygdala. CNO was injected through the cannulas to the amygdala to cause the DREADDs activate or inhibit the cholinergic cells. As a control, mice received vehicle. The feeding experiments were performed in normal conditions or after food restriction and there were either food or sugar pellets available. The pellet dispenser monitored how many pellets mice ate during the six hours after the CNO or vehicle treatment. The success of virus injections was checked after the feeding experiments by antibody dyeing. In any conditions there was no significant differences in the results due to DREADDs and treatment. Because of the small group sizes and dispersion of the results no final conclusions can be made but the additional research about this topic is needed.

Prostate cancer is one of the most common cancers in the developed countries. Prostate cancer is slowly progressing cancer but can transform into aggressive disease and metastasize. Metastases are the major cause of mortality. Androgens play an important role in the pathogenesis of prostate cancer and prostate tumors are usually dependent on androgens. Thus the aim of the treatment is to eliminate testicular androgens by surgical or medical castration and/or block the effect of androgens on the prostate with antiandrogens. Prostate cancer and new therapies to treat the disease are being investigated vigorously. Numerous in vivo models of prostate cancer have been developed. Androgen responsive animal models mimic prostate cancer more closely. There are many animal species that may be used to model prostate cancer but mouse is no doubt the most useful. Tumor models can be created by inoculating human cancer cells or solid parts of tumors into immune deficient mice. Orthotopic prostate tumor models reflect the abnormal cancer cell-stroma interactions occuring in prostate cancer. Transgenic mouse models are becoming more and more common in the research of prostate cancer. Transgenic models are able to model the initiation and progression of the disease more realistically. Growth of the orthotopic tumor is difficult to monitor without measuring serum prostate specific antigen (PSA) concentrations or using specific imaging methods. Imaging techniques, such as optical imaging, are being utilized in different in vivo models of prostate cancer. The objective of the experimental part of this thesis was to optimize bioluminescence imaging method in androgen responsive cell line LNCaP-luc2 in orthotopic model of prostate cancer. Bioluminescence imaging is based on a reaction catalyzed by a luciferase which is expressed by the tumor cells. In the ATP-dependent reaction luciferase enzyme oxidizes its substrate, luciferin, and produces light. In addition, the purpose of this study was to examine the effects of medical therapy and castration on tumor growth. Bioluminescence imaging enabled noninvasive, real-time and longitudinal monitoring of the growth of prostate tumors in this model. Quantification of the tumors with bioluminescence measurement was faster than with ultrasound sonography. It was also possible to monitor the growth of the tumors more often with bioluminescence imaging than with PSA measurements. Bioluminescence imaging was found to correlate better with serum PSA concentrations than with the actual size of the tumor. However prostate tumor size was noted to correlate better with PSA concentrations than with bioluminescence imaging in this study. Medical treatment or castration was found to have no effect on the size of the tumors when measured with bioluminescence imaging. The larger size of the tumors than expected was the probable reason for this. Bioluminescence imaging is not suitable for large or necrotic tumors because this imaging method can only be applied in living cells. In addition, a successful luciferin injection is essential for the proper utilization of bioluminescence imaging in this model. More studies are needed to validate the model for example in proving the effects of the medical therapies.

The field of stem cell research is hotter than ever, because still today, the goal for easily achievable stem cells for the use of tissue engineering and stem cell therapies, is yet to be achieved. Also, human stem cell based test systems are potential replacements of present animal test models. The ongoing obesity epidemic creates pressure for scientists to resolve the causes behind it. One way of approaching the problem, is the study of adipogenesis with the use of a in-vitro cell model. This have already been done for a while, with rodent based cell models, but the present study took the human obesity research a bit closer to its subject by using humane adipose tissue derived mesenchymal stem cells (hASC). Also, the adipogenic induction is executed with a human adipose tissue extract (ATE). Epidemiologically, the rise in obesity rates correlates at some level, with the occurrence of known endocrine disrupting chemicals in our environment. These include e.g. some pesticides and plasticizers, such as tributyltin (TBT), bis(2-ethylhexyl)phthalate (DEHP) and bisphenol A (BPA). In the present study, the effects of a variety of concentrations, ranging from 50nM to 100µM of BPA, on ATE induced adipogenesis of hASCs, was studied. The accumulation of triglycerides - a key parameter for adipogenesis - is evaluated with the use of oil-red-o (ORO) staining and photometric measurements. A set of tests was executed to find out if BPA possesses adipogenic, synergistic or antiadipogenic properties in this particular test system. No significant antiadipogenic, nor synergistic effects were seen. Some antiadipogenic effects were seen throughout the study, but without any dose-dependence. This study also showed need for further development of the test. ORO staining needs to be further standardized to increase accuracy, different batches of ATE may cause variation in the results. All and all the test system is relatively easily modified and when fully functional, it is a great tool for screening for substances affecting our adipose tissue, and also for enhancing our knowledge on human adipogenesis in whole.

There are significant inter-individual differences in the effects of drugs. These differences can be caused by, for example, other diseases, adherence to treatment, or drug-drug interactions. A drug-drug interaction can lead to an increase in the concentration of the active substance in the circulation (pharmacokinetic interactions) or a change in the effect of the drug without changes in plasma concentration (pharmacodynamic interactions). A drug-drug interaction can change the efficacy of a drug or affect the adverse drug reaction profile. The individual’s genetic background, such as diversity in drug-modifying enzymes (polymorphism), also has an effect on the efficacy and the risk for adverse drug reactions of some drugs. A pharmacogenetic test can be used to study how genetic factors affect drug treatments. The aim of this master's thesis was to examine the possibilities of personalized migraine pharmacotherapy from the perspective of pharmacogenomics and drug-drug interactions. Four online drug-drug interaction databases available in Finland were compared. Inxbase is the most widely used interaction database by physicians in Finland and it is also integrated into Finnish pharmacy systems. Other databases used in this study were the international professional database Micromedex as well as Medscape Drug Interaction Checker and Drugs.com Drug Interactions Checker. The latter two are open-access databases available for healthcare professionals and patients. Interaction searches were conducted in the selected databases between acute and prophylactic drugs used for the treatment of migraine (e.g. bisoprolol-sumatriptan). Fourteen acute and 12 prophylactic drugs were selected for this study based on the Current Care Guidelines in Finland (Käypä hoito), and the data were collected in Excel spreadsheets. The first search was completed in December 2019 and the second search in March 2020. In this study, many potential interactions were found between acute and prophylactic drugs used to treat migraine in Finland. For more than half of the drug pairs studied, a potential interaction was found in at least one of the databases. There were significant differences between the interaction databases regarding which interactions the database contains and how the severity of the interactions was classified. Of the interactions found, only 45% were found in all four databases, and each database contained interactions that were not found in the other databases. Even very serious interactions or drug pairs classified as contraindicated were not found to be consistently presented across all four databases. When selecting drug treatment for a migraine patient, potential drug-drug interactions between acute and prophylactic drugs as well as the patient's genetic background should be considered. Individualizing migraine treatment to achieve the best efficacy and to reduce the risk for adverse drug reactions is important because migraine as a disease causes a heavy burden on individuals, healthcare, and society. Pharmacogenetic tests particularly developed to help choosing migraine treatment are not yet available, but tests are available for few other indications in both public and private healthcare. The use of these tests in clinical practice will increase as physicians’ pharmacogenetic knowledge and scientific evidence on pharmacogenetic tests increase. Utilization of pharmacogenetic data requires that test results are stored in electronic health records so that they are available in the future, when changes are made to drug treatment of individuals. More studies are warranted to better understand the clinical impact of pharmacogenomics and drug-drug interactions in migraine care.

Oncolytic viruses have been extensively studied for the treatment of cancer. They are genetically engineered viruses, which are able to selectively infect and kill the cancer cells causing no harm to normal cells. Adenoviruses are the most commonly used viruses in the gene therapy field and their oncolytic variants are currently under evaluation in many clinical trials. The cell killing properties of oncolytic adenoviruses against the cancer cells have been known for a long time. In addition, it is known that they can activate immune system. To achieve more selective and effective antitumor effects several modifications of oncolytic adenoviruses have been studied. During my internship I worked on the development of a new cancer vaccine platform based on peptide-coated conditionally replicating adenovirus (PeptiCRAd). The PeptiCRAd technology consists of a serotype 5 adenoviruses which are coated with tumorderived peptides. The aim of the thesis was to evaluate the antitumor efficacy of the PeptiCRAd. The cytopathic effects of the PeptiCRAd were studied in vitro using human adenocarcinoma cell line, A549. In this experiment three different treatments were used to study the cytopathic effects of the PeptiCRAd and Ad5Δ24-CpG- virus or polyK-SIINFEKL- peptide alone. The cell viability was assayed using MTS reagent and quantified by spectrophotometer. The antitumor effects were also studied in vivo using immunocompetent C57BL/6 mice bearing B16-OVA melanoma tumors. Tumor-bearing mice were treated with Ad5Δ24-CpG- virus, SIINFEKL- peptide or the PeptiCRAd. To evaluate the antitumor effects, tumor volume was observed after the treatments. In this study, I show that PeptiCRAd and Ad5Δ24-CpG- virus both have oncolytic effects in vitro against A549 cells. In vitro Ad5Δ24-CpG- virus showed significantly better cytopathic effects at high concentration compared to PeptiCRAd. In vivo the PeptiCRAd showed strongest antitumor effect on the growth of established tumors. At the end of the experiment the volume of the tumor was significantly smallest in the PeptiCRAd group.

Cytochrome P450 (CYP) enzymes are important catalysers in the first phase of drug metabolism. Roughly two thirds of drugs are oxidized via CYP enzymes, which enable the further modification of drugs, and their excretion. In this thesis, human liver microsomes containing the main hepatic CYP enzymes were immobilized on thiol-ene based micropillar arrays and their stability was evaluated using a CYP2C9 isoenzyme specific luminescent substrate, Luciferin-H. The aim of the study was to develop microfluidic immobilized enzyme reactors (IMERs) for studying enzyme kinetics and drug-drug interactions. For this purpose, the instability issues associated with previously reported CYP-IMERs were carefully addressed. The CYP immobilization protocol used was based on a protocol previously developed in the context of other research projects and relied on biotinylation of human liver microsomes (HLM) with help of fusogenic liposomes. The biotinylated HLMs were then attached to the streptavidin-modified thiol-ene surfaces. The CYP activity was determined by utilizing microfluidics under continuous flow conditions (typically 5 μL/min) in the presence of NADPH. The luminescent metabolite formed by the CYP2C9 enzymes was quantified with a commercial well-plate reader from fractions collected at the microreactor outlet. Half-life was used to compare the differences between enzyme stabilities reached via different immobilization conditions. The effects of flow rate and reaction temperature on the stability of the CYP-IMERs was evaluated together with addition of antioxidative agents and reactive oxygen species (ROS) scavengers. Different functionalization steps as well as storage time and conditions were studied. With Luciferin-H as the model substrate of CYP2C9, the CYP-IMERs showed higher activity and stability at room temperature than at +37 °C. The peak activity could be increased via optimization of the immobilization protocol, though long-term storage diminished the peak activity. The activity of the IMERs typically attenuated within 1-2 hours with little or no improvement achieved via optimization of the immobilization or operation conditions. Only upon addition of the ROS scavengers, the peak activity and stability of the CYP-IMERs could be slightly improved. After functionalization, the IMERs maintained their activity until the time of use when stored in +4 °C for up to 2 weeks, but re-use of IMERs was not possible.

Background: Poor health literacy (HL) is associated to increased hospitalization and decreased seeking for screenings. Shared decision making can increase patient knowledge, decrease anxiety over the care process, improve health outcomes and reduce health care costs. Little is known about factors influencing health literacy and participation in treatment decision making in different population groups. Objectives: To investigate factors predicting HL and participation in the treatment decision making. Methods: A cross-sectional population online survey conducted in Finland in 2019 by Finnish Medicines Agency. Both health literacy and participation in the decision making were assessed by three statements that sum variables were created with score 1-5 (Cronbach’s alpha value 0.584 and 0.810). Age, gender, education, household income and most common chronic diseases were chosen as possible predicting factors. Two-variable Pearson’s chi-squared test was first used to find significant factors followed by logistic regression analysis to take into account several variables. Results: Of all the respondents (n=2104) 76.5% had good HL and 73.4% had willingness to participate in the treatment decision making. In the two-variable test older age (p<0.001), lower education (p<0.001), lower household income (p=0.001), higher number of chronic diseases (p=0.003), having cardiovascular diseases (p=0.003), diabetes (p=0.029) and cancer (p=0.001) predicted poorer health literacy. Male gender (p=0.001), not having chronic diseases (p=0.001), not having a musculoskeletal disorder (p=0.050) or mental health disorders (p<0.001) predicted poorer participation in the treatment decision making. In the logistic regression analysis older age and having cancer predicted poorer health literacy. Male gender and not having mental health disorders predicted less willingness to participate in the decision making. Conclusions: Older age and cancer predicts poorer health literacy and male gender poorer willingness to participate in the decision making. Further research should focus on investigating more in detail the contributing factors to these findings, and how health literacy in elderly and men’s involvement to the decision making could be improved.

Pharmaceutical companies are required to comply with fair market guidelines and regulations. However, definition of fair market value (FMV) in clinical trial is not unambiguous. In literature are some suggestions how to determine the phenomenon of FMV in clinical trial. Understanding the FMV and how it should be applied into practice when conducting clinical research is challenging. This study provides more focused information on FMV in clinical trials and its determination. FMV should be determined for research-related activities in clinical drug research. FMV of research related activities can be consistent if similar sites are performing similarly conducted studies for similar sponsors. Therapeutic area and geographical location of the trial site can also influence for the FMV. This study was performed in co-operation with Roche. The aim of the study was create a consistent and transparent method to assist in the determination of FMV in medical drug research in relation to the payments paid by the sponsor to the sites. Clinical trial agreements (CTA) and associated agreements were analysed to investigate FMV of research-related activities by study site, study type, therapeutic area and geographical area. Average price and price range of each research-related activity from previous CTAs and associated agreements of Roche Finland was calculated. Based on available data from literature and study results research-related activities and factors affecting to the FMV of clinical trials were discussed to create comprehensive understanding of FMV in clinical drug research. Based on this study average price of the specific research-related activities can be different by therapy area, site, study type and geographical area. All these factors are relevant when assessing FMV of specific research-related activity. Studied therapy area and site seems to have the most important impact when evaluating FMV. For some research-related activities such as national coordinator investigator (NCI) fee price ranges could be very big whereas in other research-related activities such as pharmacy fees prices could be quite similar. Some research-related activities were very study specific which affected evaluation of those activities. CTAs and associated agreements are valid documents to gather information assessing FMV of research-related activities in medical drug research. Average price and price range of the research related activity can be used when assessing FMV in medical drug research. However, price of the specific research-related activity need to be evaluated considering the studied therapy area, site, study type and geographical area.

The effect of genes on drug response is studied in the field of pharmacogenetics. Genetic polymorphism occurs in several genes that code drug metabolizing enzymes or drug transporters. A protein coded by a variant gene may be dysfunctional, which can affect the efficiency and safety of the substrate drug individually. The common polymorphisms of the gene ABCG2 coding the efflux transporter BCRP and the gene SLCO1B1 coding the influx transporter OATP1B1 are associated with the interindividual variation in the effectiveness and tolerability of the cholesterol-lowering statins. In this study, the effects of the polymorphisms ABCG2 c.421C>A and SLCO1B1 c.521T>C on rosuvastatin concentration in plasma and the liver were studied with two different pharmacokinetic models. The developed liver model illustrating the enterohepatic circulation of drugs was compared to a commercial Simcyp model. According to the simulations with both models, the effect of the polymorphisms of OATP1B1 and BCRP on the plasma concentration of rosuvastatin is additive. The plasma concentration increases up to fourfold if the same individual has homozygous polymorphic forms of both the OATP1B1 and the BCRP. Based on the modellings, the change of the rosuvastatin concentration in the liver owing to polymorphism does not follow the same pattern as in plasma. In consequence of the polymorphism of the BCRP, the rosuvastatin concentration rises two to three times larger in the liver, which is the site of action of the statins. The polymorphism of the OATP1B1 instead causes the liver concentration to decrease little compared to the wild type. In conclusion, the efflux transporter BCRP seems to have a greater significance on regulating the concentration of rosuvastatin in the liver than the influx transporter OATP1B1. Computer modelling is worth exploiting as a supportive method of other study methods in the pharmacogenetic research, for example when the relative significance of separate transporter proteins is evaluated.

In early clinical trials of drug development capsule is preferable compared with other solid dosage forms, including tablets, because of its simplicity and blinding capabilities. However a simple capsule formulation is not viable in large-scale production. Usually it's either switched to an economical tablet formulation or to another capsule formulation that can be manufactured on large-scale equipment. Tablets are nearly always formulated for commercialization if they're not technologically impossible to manufacture for a reason which could be bad compression or solubility of a drug. Tablet-pressing process sets more-demanding requirements for pharmaceutical powder properties than encapsulation process, because tablet-press uses larger compression forces and it measures the dose in a different way. The most common problems faced when switching from a capsule dosage form to tablet-pressing process are poor powder flow properties and weak mechanical strength, capping and lamination of tablets. The purpose of this work was to investigate the critical pharmaceutical and technical properties to succeed in switching from a capsule dosage form to a tablet dosage form and tablet-pressing process. The starting point of this work was a simple capsule formulation consisting of carbidopa, directcompressible mannitol and pregelatinized maize starch. The simple formulation was used to build up two mixture designs consisting of very different powder properties to study the critical powder properties and process variables involved in the switch. The capsules were filled on a dosating nozzle capsule-filling machine and the tablets were pressed on a pneumohydraulic tablet press. Weight variability, disintegration time, encapsulation and tabletability were used as the responses of the dosage forms. As a result of the study the automatic capsule-filling machine filled many different types of powders in capsules with low fill-weight variability. The most critical powder properties affecting the capsulefilling process were the particle size, bulk and tapped densities and cohesion of powder. Avicel PH200 improved the tabletability and flowability of the powders, but it also increased the fill-weight variability of the capsules. In this work single powder flow properties described only the flowability of a powder, but they did not determine the performance of a powder in the processes. Therefore, measuring various powder flow properties and correlating them to a manufacturing system is necessary to understand the process. Avicel PH102 was proved to work as an ideal reference material for evaluating the sufficiency of the flow properties of a powder in the tablet-pressing process.