Due to copyright issues, an electronic copy of the thesis must be ordered from the faculty. For the faculty to have time to process the order, the order must be received by the faculty at the latest 2 days before the public defence. Orders received later than 2 days before the defence will not be processed. After the public defence, please address any inquiries regarding the thesis to the candidate.
Trial Lecture – time and place
See Trial Lecture.
Adjudication committee
- First opponent: Professor Josef Guber, Cantonal Hospital of Sankt Gallen,
- Second opponent: Professor Simona Delia Nicoară, “Iuliu Haţieganu” University of Medicine and Pharmacy,
- Third member and chair of the evaluation committee: Associate Professor Elisabeth Qvigstad, University of Oslo
Chair of the Defence
Professor Fei Fang-Stavem, University of Oslo
Principal Supervisor
Professor II Goran Petrovski, University of Oslo
Summary
Diabetes can damage the small blood vessels of the retina and lead to diabetic retinopathy, a major cause of vision impairment among working-age adults. The disease may progress before noticeable symptoms develop, highlighting the need for improved biomarkers of disease progression and new therapeutic targets.
The thesis aimed to characterise the metabolic environment of the eye in different stages of diabetic retinopathy and to identify potential biomarkers and therapeutic targets using targeted and untargeted mass spectrometry of undiluted vitreous samples from patients undergoing vitrectomy. A second aim was to develop an ex vivo porcine eye model for studying the movement of molecules within the eye and its potential application in ocular drug development.
Metabolomic profiling revealed distinct stage-associated changes in the vitreous of patients with diabetes and diabetic retinopathy, demonstrating that progression of the disease is accompanied by characteristic alterations in ocular metabolism.
Several amino acids, including arginine, methionine, threonine and proline, as well as carnitine, showed increased levels with advancing disease, whereas metabolites associated with antioxidant defence, membrane integrity and neuronal function, including taurine, ascorbate, choline and N-acetylaspartate, were reduced at different stages of diabetic retinopathy. These findings provide a rationale for further investigating whether correction of selected metabolic deficiencies, including through dietary supplementation, could have a role as an adjunctive strategy in diabetic retinopathy.
In the ex vivo porcine eye model, the movement of molecules between the anterior and vitreous chambers was shown to depend on time and molecular properties. The model provides a controlled experimental platform for studying ocular drug distribution and may contribute to the development and optimisation of future ocular therapies.
Overall, the thesis demonstrates that metabolomic analysis of the vitreous can provide new insights into the molecular changes associated with diabetic retinopathy and identify potential biomarkers and therapeutic targets for further investigation.
Additional information
Contact the research support staff.