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Abdullatif Babakr,1 Mohamed Mukhtar,1Mohammad Althubiti,1 Hiba Al-Amodi,1 Riyad Almaimani,1 Mohamed Mahmoud Nour Eldin,1 Mohamed Elzubeir Abdalla,1 Wesam Nasif1,2 1Department of Medical Biochemistry, Faculty of Medicine, Umm Al-Qura University, Makkah, Kingdom of Saudi Arabia; 2Molecular Biology Department, Genetic Engineering and Biotechnology Research Institute, Sadat City University, Sadat City, EgyptCorrespondence: Abdullatif Babakr, Department of Medical Biochemistry, Faculty of medicine, Umm Al-Qura University, Abdia, Makkah, Kingdom of Saudi Arabia, Tel +966-25270000/4322, Fax +96625270000/4319, Email atbabakr@uqu.edu.saBackground: Hyperlipidemia is a common risk factor for atherosclerosis, heart diseases, and other pathological conditions. The factors leading to the oxidation of native low-density lipoproteins remain of valuable importance for a better understanding of the mechanisms leading to these pathologies. The aim of the present study was to evaluate the association between lipid status and the levels of oxidized low-density lipoproteins and 8-hydroxy-2´-deoxyguanosine.Methods: One hundred and fourteen participants were enrolled. Lipid profile parameters were measured and used individually to categorize subjects into two groups of normal and hyperlipidemic cases according to the international reference ranges. Oxidized low-density lipoproteins and 8-hydroxy-2´-deoxyguanosine were then compared in normal and high lipid profile groups. The obtained results were then statistically analyzed.Results: 8-Hydroxy-2´-deoxyguanosine was found to be positively correlated with hypercholesterolemia, hypertriglyceridemia, and high levels of low-density lipoproteins (r = 0.53, 0.41, and 0.60), respectively (p< 0.001). A positive correlation was observed also between the levels of oxidized low-density lipoproteins and the same lipid profile parameters (r = 0.42, 0.31, and 0.45), respectively (p< 0.001).Conclusion: The present study suggests that disturbance in lipid profile may result in increased levels of oxidized low-density lipoproteins and oxidative stress in the study group; however, a larger sample is needed to confirm the present findings.Keywords: oxidized LDL, 8-OH-dG, dyslipidemia, DNA damage

We have defined five sev genes by genetic analysis of Schizosaccharomyces pombe mutants, which are defective in both proliferation and sporulation. sev1+/cdt2+ was transcribed during the G1-S phase of the mitotic cell cycle, as well as during the premeiotic S phase. The mitotic expression of cdt2+ was regulated by the MCB-DSC1 system. A mutant of a component of DSC1 affected cdt2+ expression in vivo, and a cdt2+ promoter fragment containing MCB motifs bound DSC1 in vitro. Cdt2 protein also accumulated in S phase and localized to the nucleus. cdt2 null mutants grew slowly at 30° and were unable to grow at 19°. These cdt2 mutants were also medially sensitive to hydroxyurea, camptothecin, and 4-nitroquinoline-1-oxide and were synthetically lethal in combination with DNA replication checkpoint mutations. Flow cytometry analysis and pulsed-field gel electrophoresis revealed that S-phase progression was severely retarded in cdt2 mutants, especially at low temperatures. Under sporulation conditions, premeiotic DNA replication was impaired with meiosis I blocked. Furthermore, overexpression of suc22+, a ribonucleotide reductase gene, fully complemented the sporulation defect of cdt2 mutants and alleviated their growth defect at 19°. These observations suggest that cdt2+ plays an important role in DNA replication in both the mitotic and the meiotic life cycles of fission yeast.