Collaborations with Miral Dizdaroglu: expanding on connections between oxidative DNA damage and aging and disease.

PURPOSE: The goal of this long-term collaboration between Vilhelm A. Bohr and Miral Dizdaroglu was to investigate oxidative DNA damage and DNA repair mechanisms and their links to aging, neurodegeneration, and disease. Using GC/MS assays, the collaboration aimed to identify other endogenous DNA lesions like FapyGua and FapyAde beyond the standard 8-oxo-Gua marker to determine their biological significance and distribution in nuclear and mitochondrial DNA. RESULTS: DNA Repair Pathways: Identified OGG1 and NTH1 as the primary glycosylases for formamidopyrimidines and demonstrated that CSB protein stimulates NEIL1 activity.Disease & Aging: Found that Cockayne syndrome group B (CSB) and Xeroderma pigmentosum group A (XPA) patients are deficient in repairing specific oxidative lesions, linking these defects to premature aging. In lung cancer, reduced hOGG1 expression correlated with elevated 8-oxo-Gua.Genomic Insights: Initial DNA damage induction was found to be similar in nuclear and mitochondrial DNA, challenging the assumption that mitochondria accumulate significantly more DNA damage. CONCLUSION: The research established that oxidative damage extends far beyond 8-oxo-Gua and that Base Excision Repair (BER) defects are central to the pathology of cancer and neurodegeneration. The findings emphasize that a multi-lesion approach is essential for understanding the link between oxidative stress and disease.