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Increasing evidence suggests that neurodevelopmental alterations might contribute to increase the susceptibility to develop neurodegenerative diseases. We investigate the occurrence of developmental abnormalities in dopaminergic neurons in a model of Parkinson’s disease (PD). We monitor the differentiation of human patient-specific neuroepithelial stem cells (NESCs) into dopaminergic neurons. Using high-throughput image analyses and single-cell RNA sequencing, we observe that the PD-associated LRRK2-G2019S mutation alters the initial phase of neuronal differentiation by accelerating cell-cycle exit with a concomitant increase in cell death. We identify the NESC-specific core regulatory circuit and a molecular mechanism underlying the observed phenotypes. The expression of NR2F1, a key transcription factor involved in neurogenesis, decreases in LRRK2-G2019S NESCs, neurons, and midbrain organoids compared to controls. We also observe accelerated dopaminergic differentiation in vivo in NR2F1-deficient mouse embryos. This suggests a pathogenic mechanism involving the LRRK2-G2019S mutation, where the dynamics of dopaminergic differentiation are modified via NR2F1. publishedVersion

Renal fibrosis is a progressive histological manifestation leading to chronic kidney disease (CKD) and associated with mitochondrial dysfunction. In previous work, we showed that Bemcentinib, an Axl receptor tyrosine kinase inhibitor, reduced fibrosis development. In this study, to investigate its effects on mitochondrial dysfunction in renal fibrosis, we analysed genome-wide transcriptomics data from a unilateral ureter obstruction (UUO) murine model in the presence or absence of bemcentinib (n = 6 per group) and SHAM-operated (n = 4) mice. Kidney ligation resulted in dysregulation of mitochondria-related pathways, with a significant reduction in the expression of oxidative phosphorylation (OXPHOS), fatty acid oxidation (FAO), citric acid cycle (TCA), response to reactive oxygen species and amino acid metabolism-related genes. Bemcentinib treatment increased the expression of these genes. In contrast, AKT/PI3K signalling pathway genes were up-regulated upon UUO, but bemcentinib largely inhibited their expression. At the functional level, ligation reduced mitochondrial biomass, which was increased upon bemcentinib treatment. Serum metabolomics analysis also showed a normalizing amino acid profile in UUO, compared with SHAM-operated mice following bemcentinib treatment. Our data suggest that mitochondria and mitochondria-related pathways are dramatically affected by UUO surgery and treatment with Axl-inhibitor bemcentinib partially reverses these effects. publishedVersion

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating disease usually presenting after infection. Emerging evidence supports that energy metabolism is affected in ME/CFS, but a unifying metabolic phenotype has not been firmly established. We performed global metabolomics, lipidomics, and hormone measurements, and we used exploratory data analyses to compare serum from 83 patients with ME/CFS and 35 healthy controls. Some changes were common in the patient group, and these were compatible with effects of elevated energy strain and altered utilization of fatty acids and amino acids as catabolic fuels. In addition, a set of heterogeneous effects reflected specific changes in 3 subsets of patients, and 2 of these expressed characteristic contexts of deregulated energy metabolism. The biological relevance of these metabolic phenotypes (metabotypes) was supported by clinical data and independent blood analyses. In summary, we report a map of common and context-dependent metabolic changes in ME/CFS, and some of them presented possible associations with clinical patient profiles. We suggest that elevated energy strain may result from exertion-triggered tissue hypoxia and lead to systemic metabolic adaptation and compensation. Through various mechanisms, such metabolic dysfunction represents a likely mediator of key symptoms in ME/CFS and possibly a target for supportive intervention. publishedVersion

CubeSat-prosjekter øker i andel, og behovet for pålitelighetsverktøy og data er nøkkelkomponenter for å unngå tidlig tap og oppnå suksesskriteriene for oppdraget. Feiltreeanalyse (FTA) er en mye brukt metode for å analysere farer og beregne systemets generelle pålitelighet. Likevel har konvensjonell feiltreanalyse ulemper når mangler på statistisk data forhindrer at en kvantitativ analyse kan bli gjennomført. I slike tilfeller kan man benytte fagkunnskap for å hjelpe med å modellere farene. Imidlertid synes folk det er vanskelig og upraktisk å tilby sannsynlighetsestimater basert på eksakte tall og er mer komfortable med å bruke språklige begreper når de estimerer sannsynligheten for at en hendelse inntreffer. De ordlige uttrykkene gir mer spillerom og inkluderer usikkerhet, men konvensjonell FTA-representasjon kan ikke håndtere denne språklige prosedyren. I denne artikkelen foreslås en fuzzy logisk tilnærming for å overvinne disse hindringene og tillate eksperttilrettelegging å bli brukt for å gjøre kunnskapen deres om til sannsynlighetstall ved å bruke språklige variabler som et verktøy. Feilmodus identifisert fra Failure Modes, Effects and Criticality Analyse (FMECA) har blitt rangert i en hierarkisk prioriteringsrekkefølge med hensyn til alvorlighetsgraden for HYPSO-oppdragsmålene. Det ble konstruert feiltrær for disse feilmodusene og grunnleggende hendelser ble identifisert. Et anonymt spørreskjema ble utviklet for å samle teammedlemmenes språklige evalueringer og deres tillitsvurdering for de respektive kjernehendelsene. For å transformere disse språklige estimatene til analytiske data som skal brukes for kvantitative evalueringer av komponentene, delsystemene og for de overordnede underkategoriene til satellitten, benyttes en Similiarity Agreement’s Method aggregering av risikoen for teamekspertenes estimater. Selv om denne fuzzy-baserte metoden er brukt på andre bransjeapplikasjoner, er dens potensielle nytteverdi aldri brukt tidligere i SmallSatsektoren etter det forfatteren er kjent med og er derfor opprinnelig utforsket i denne oppgaven. Til slutt i denne oppgaven implementeres en fuzzy feiltremodell for å kvantitativt teste årsak-virkningsforholdet til disse satellittspesifikke farene og feilmodusene. Resultatene fra denne analysen er sannsynligheten for at en spesifikk hendelse inntreffer og betydningen av de mulige påvirkningene er eksplisitt vist ved viktighetsrangeringer. Funnene som er presentert her kan hjelpe risikoanalytikere med å forberede sine risikotiltak for å effektivt håndtere risikoene i et satellittsystem. CubeSat projects are on the rise and the need for reliability tools and data is a key component in avoiding infant mortality and reach mission success criteria. Fault tree analysis (FTA) are one such widely used method in order to analyze hazards and calculating a system’s overall reliability. Yet, conventional FTA faces shortcomings when a lack of statistical data prevents a quantitative analysis being performed. In such cases, one can rely on expert knowledge in order to help model the hazards. However, people find it difficult and inconvenient to offer probability estimations based on exact numbers and are more confident using linguistic terms when estimating. The terms provide more leeway and includes uncertainty but conventional FTA representation cannot handle this linguistic procedure. In this paper, a fuzzy logic approach is proposed in order to overcome these obstacles and allow expert facilitation to be used in order to turn their knowledge into failure probability numbers using linguistic variables as a gateway. Failure modes identified from the Failure Modes, Effects, and Criticality Analysis (FMECA) were ranked in a hierarchical order of prioritization with respect to severity for the HYPSO missions goals. Fault trees were constructed for these failure modes and basic events identified. An anonymous questionnaire was devised to gather the team members linguistic evaluations and their confidence rating for the respective basic events. In order to transform these linguistic estimates into analytical data to be used for quantitative evaluations of the components, subsystems and for the overall subcategories of the satellite, a Similiarity Agreement’s Method aggregating the risks of the team experts’ estimations is utilized. While this fuzzy-based method has been applied to other industry applications, its potential usefulness applied to the SmallSat sector is to the author’s knowledge undiscovered territory and originally explored in this paper. Finally, a fuzzy fault tree model is implemented in this thesis in order to quantitatively test the cause-effect relationship of these satellite specific hazards and failure modes. The results of this analysis are the likelihood of possibility for a specific event and the significance of possible contributing events explicitly shown by importance measures. The findings presented here can help risk analysts prepare their mitigation measures to effectively manage the risks in a satellite system.

Temaet for denne masteroppgaven er norske offisielle unnskyldninger. Dette er statlige beklagelser for tidligere ugjerninger begått av nordmenn eller norske myndigheter. Fra 2012 til 2018 ble fire slike unnskyldninger rettet mot henholdsvis norske jøder, krigsseilerne, norske rom og «tyskerjentene». Fremveksten av slike norske unnskyldningstaler aktualiserer en analyse av talene for å kartlegge sjangerens kjennetegn og betydning. Med retorisk sjangeranalyse som rammeverk undersøker studien sjangerens karakteristikker og dens potensial til å påvirke politiske og sosiale forhold. I analysen undersøker jeg blant annet hvordan sjangeren kan brukes til å forplikte det retoriske publikumet til spesifikke verdier. Dette publikummet består både av gruppene unnskyldningene er rettet mot og det øvrige norske folk. I oppgaven undersøker jeg hvordan retorene skaper og definerer dette publikumet og kartlegger sjangerens muligheter til å definere og forme nordmenns kollektive norske identitet. Oppgaven viser at sjangeren forutsetter en taler med en særegen form for retorisk handlekraft. Dette betyr at retoren må ha makten til å fremføre den offisielle unnskyldningen og til å orkestrere en talesituasjon som muliggjør en erkjennelse av tidligere feil. Sjangerens viktigste karakteristikk er de ensartede erkjennelsene av fortidens ugjerninger. Disse redegjørelsene tar form av historiefortellinger som erkjenner norske myndigheters aktørrolle og anerkjenner gruppene som mottar unnskyldningen som historiens offer. Gjennom slike fortellinger kan sjangeren brukes til å styrke nordmenns forpliktelse til liberale verdier som frihet, åpenhet og likeverd. Sjangeren har også et potensial til å anerkjenne minoriteter som norske ved å definere gruppens kultur som norsk og ved å forankre gruppens historiske tilhørighet til landet. På denne måten tildeles gruppen en stemme og en rett til å bli lyttet til. Sjangeren har således potensial til å påvirke nordmenns forståelse av hva som er norsk kultur og til å utvide kategorien «nordmann». Studien avdekker altså hvordan offisielle unnskyldninger kan påvirke relasjoner mellom stat og minoritet, og ikke minst hvordan slike minoriteter kan innlemmes i et nasjonalt fellesskap gjennom retorikk. På et overordnet plan gir studien innsyn i hvordan en retorisk sjanger kan påvirke et samfunns håndtering av fortiden, og måten offisielle forståelser av historien kan forme kollektive verdier og identiteter. På denne måten øker studien vår forståelse av retorikkens politiske og sosiale funksjoner.

In this thesis, we look at annual- and sustainability reports as a proxy to sustainability efforts for companies listed on the OSEAX-index. By using textual analysis on annual and sustainability reports, along with other sustainability measures, we then investigate the link between profitability and various types of sustainability efforts in a Norwegian context. The study utilizes a custom crafted database of 133 companies, 504 annual reports, and 111 sustainability/ESG/CSR-reports, along with accounting data and secondary variables resulting in 639 observations and a wide range of sustainability variables spanning over 5 years. I find a positive link between sustainability efforts and profitability for the sample, and the proxy-approach proves promising. However, I am not able to determine any categorical prioritization of sustainability efforts, which gives support to the existing common practice of contextual assessments and materiality matrices when it comes to sustainability effort prioritization. The thesis struggles with data availability and the methodological question of how to filter and aggregate easily accessible sources of empirical information. It contributes to existing sustainability research by providing an original approach to sustainability efforts measuring. The results are generalisable for companies listed on the OSEAX-index, however the thesis is conditioned on the acceptance of the proxy-solution to measure sustainability efforts. There is also no way of determining causality in the study, but the results are robust with varied robustness-measures in place. nhhmas

Background Epithelial to mesenchymal transition (EMT) is a well-characterized process of cell plasticity that may involve metabolic rewiring. In cancer, EMT is associated with malignant progression, tumor heterogeneity, and therapy resistance. In this study, we investigated the role of succinate dehydrogenase (SDH) as a potential key regulator of EMT. Methods Associations between SDH subunits and EMT were explored in gene expression data from breast cancer patient cohorts, followed by in-depth studies of SDH suppression as a potential mediator of EMT in cultured cells. Results We found an overall inverse association between EMT and the SDH subunit C (SDHC) when analyzing gene expression in breast tumors. This was particularly evident in carcinomas of basal-like molecular subtype compared to non-basal-like tumors, and a low SDHC expression level tended to have a prognostic impact in those patients. Studies in cultured cells revealed that EMT was induced by SDH inhibition through SDHC CRISPR/Cas9 knockdown or by the enzymatic inhibitor malonate. Conversely, overexpression of EMT-promoting transcription factors TWIST and SNAI2 caused decreased levels of SDHB and C and reduced rates of SDH-linked mitochondrial respiration. Cells overexpressing TWIST had reduced mitochondrial mass, and the organelles were thinner and more fragmented compared to controls. Conclusions Our findings suggest that downregulation of SDHC promotes EMT and that this is accompanied by structural remodeling of the mitochondrial organelles. This may confer survival benefits upon exposure to hostile microenvironment including oxidative stress and hypoxia during cancer progression. Electronic supplementary material The online version of this article (10.1186/s40170-019-0197-8) contains supplementary material, which is available to authorized users.

The cell penetrating peptide, Pep-1, has been shown to facilitate cellular uptake of foreign mitochondria but further research is required to evaluate the use of Pep-1-mediated mitochondrial delivery (PMD) in treating mitochondrial defects. Presently, we sought to determine whether mitochondrial transplantation rescue mitochondrial function in a cybrid cell model of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) disease. Following PMD, recipient cells had internalized donor mitochondria after 1 h, and expressed higher levels of normal mitochondrial DNA, particularly at the end of the treatment and 11 days later. After 4 days, mitochondrial respiratory function had recovered and biogenesis was evident in the Pep-1 and PMD groups, compared to the untreated MELAS group. However, only PMD was able to reverse the fusion-to-fission ratio of mitochondrial morphology, and mitochondria shaping proteins resembled the normal pattern seen in the control group. Cell survival following hydrogen peroxide-induced oxidative stress was also improved in the PMD group. Finally, we observed that PMD partially normalized cytokine expression, including that of interleukin (IL)-7, granulocyte macrophage–colony-stimulating factor (GM-CSF), and vascular endothelial growth factor (VEGF), in the MELAS cells. Presently, our data further confirm the protective effects of PMD as well in MELAS disease.

Item does not contain fulltext Mitochondria play a key role in signal transduction, redox homeostasis and cell survival, which extends far beyond their classical functioning in ATP production and energy metabolism. In living cells, mitochondrial content ("mitochondrial mass") depends on the cell-controlled balance between mitochondrial biogenesis and degradation. These processes are intricately linked to changes in net mitochondrial morphology and spatiotemporal positioning ("mitochondrial dynamics"), which are governed by mitochondrial fusion, fission and motility. It is becoming increasingly clear that mitochondrial mass and dynamics, as well as its ultrastructure and volume, are mechanistically linked to mitochondrial function and the cell. This means that proper quantification of mitochondrial morphology and content is of prime importance in understanding mitochondrial and cellular physiology in health and disease. This review first presents how cellular mitochondrial content is regulated at the level of mitochondrial biogenesis, degradation and dynamics. Next we discuss how mitochondrial dynamics and content can be analyzed with a special emphasis on quantitative live-cell microscopy strategies.

Far infrared radiation (FIR) is currently investigated as a potential therapeutic strategy in various diseases though the mechanism is unknown. Presently, we tested if FIR mediates beneficial effects in a cell model of the neurodegenerative disease spinocerebellar ataxia type 3 (SCA3). SCA3 is caused by a mutation leading to an abnormal polyglutamine expansion (PolyQ) in ataxin-3 protein. The consequent aggregation of mutant ataxin-3 results in disruption of vital cell functions. In this study, neuroblastoma cells (SK-N-SH) was transduced to express either non-pathogenic ataxin-3-26Q or pathogenic ataxin-3-78Q proteins. The cells expressing ataxin-3-78Q demonstrated decreased viability and increased sensitivity to metabolic stress in the presence rotenone, an inhibitor of mitochondrial respiration. FIR exposure was found to protect against these effects. Moreover, FIR improved mitochondrial respiratory function, which was significantly compromised in ataxin-3-78Q and ataxin-3-26Q expressing cells. This was accompanied by decreased levels of mitochondrial fragmentation in FIR treated cells, as observed by fluorescence microscopy and protein expression analysis. Finally, the expression profile LC3-II, Beclin-1 and p62 suggested that FIR prevent the autophagy inhibiting effects observed in ataxin-3-78Q expressing cells. In summary, our results suggest that FIR have rescuing effects in cells expressing mutated pathogenic ataxin-3, through recovery of mitochondrial function and autophagy.

Optimal mitochondrial function is maintained by fission and fusion processes that shape the mitochondrial network and morphology, the elimination of dysfunctional mitochondrial through mitophagy and the generation of new through biogenesis. These processes are crucial for adaptation during stress conditions, and have been linked to diseases. In this study we investigated mitochondrial stress related protein expression after exposing cultured SH-SY5Y neuroblastoma cells to sub-lethal doses of OXPHOS inhibitors for 72 hours. Our focus was to investigate proteins that are involved in the dynamics, quality control and biogenesis. We found that exposure to electron transport chain inhibitors resulted in clear changes in expression of mitochondrial shaping proteins. These changes were accompanied by increased in the levels of PINK1 and p62, most apparent in the cells exposed to complex III inhibitors. The finding that inhibition of different complexes caused different responses, suggests that the effects are not caused by reduced bioenergetics function alone, and are likely to involve reactive oxygen species (ROS). Our data suggest that mitochondrial stress responses caused by OXPHOS inhibition depend on which complex that is affected. The effects on mitochondrial shaping and autophagy protein suggested that central parts of the mitochondrial quality control system were compromised, or possibly overcharged.

Summary: Emerging evidence suggests that Parkinson's disease (PD), besides being an age-associated disorder, might also have a neurodevelopment component. Disruption of mitochondrial homeostasis has been highlighted as a crucial cofactor in its etiology. Here, we show that PD patient-specific human neuroepithelial stem cells (NESCs), carrying the LRRK2-G2019S mutation, recapitulate key mitochondrial defects previously described only in differentiated dopaminergic neurons. By combining high-content imaging approaches, 3D image analysis, and functional mitochondrial readouts we show that LRRK2-G2019S mutation causes aberrations in mitochondrial morphology and functionality compared with isogenic controls. LRRK2-G2019S NESCs display an increased number of mitochondria compared with isogenic control lines. However, these mitochondria are more fragmented and exhibit decreased membrane potential. Functional alterations in LRRK2-G2019S cultures are also accompanied by a reduced mitophagic clearance via lysosomes. These findings support the hypothesis that preceding mitochondrial developmental defects contribute to the manifestation of the PD pathology later in life. : Walter, Bolognin and colleagues show the detection of mitochondrial phenotypes in NESCs derived from Parkinson's disease (PD) patients carrying the LRRK2-G2019S mutation. This supports the use of stem cells as a relevant model to study PD-associated mitochondrial defects associated to PD. Keywords: Parkinson's disease, LRRK2, neurodevelopment, stem cells, mitochondria, autophagy, mitophagy