DNA Damage and Repair in Degenerative Diseases 2014

Dear Colleagues,

There is extensive experimental evidence supporting the role of Reactive Oxygen Species (ROS)-induced oxidative stress (OS) as an emerging and plausible mechanism underlying the pathophysiology of an extent and variable number of degenerative diseases. Almost all cell macromolecules are susceptible of ROS attacks. However, the molecular architecture of nucleic acids seems to be especially attractive for free radical species, such as the hydroxyl radical (·OH). The rate of DNA damage is relatively important due to the high frequency of impacts (10⁵/cells/day) in eukaryotic organisms. Such rates immediately induce one to think of the dramatic consequences but-for the existence of an efficient and continuous DNA repair mechanism.

Maintaining genomic integrity is one of the most important objectives for plant and animal species. DNA is not only protected against potential aggressive factors, but is linked to a complex and effective repair machinery. These measures enable life-forms to avoid accumulating nucleotide damage and sequence errors. The plethora of different molecular mechanisms that help cells respond to DNA damage emphasizes the biological relevance of such repair processes. DNA damage response (DDR) must therefore be carefully reviewed and understood so as to better understand and interpret the symptoms and pathophysiology of degenerative diseases.

The mutagenic base, 8-Oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG), is one of the most abundant byproducts of DNA oxidation. 8-oxo-dG has been proposed as both an excellent marker of DNA damage and as an indicator of the degree and clinical progress of degenerative diseases (including cardiometabolic ones and cancer). In light of this, the European Standard Committee for Oxidative DNA Damage (ESCODD and ESCULA) has recognized the need to arrive at “best methods” for measuring 8-Oxo-DG in DNA and urine.

Lesions in genomic DNA are known to be the etiology of many diseases, including neurodegeneration and tumor development. Unstable DNA molecules may no longer be able to coordinate regulatory orders from the nucleus to the cytoplasm, and may therefore cause such aforementioned ailments. A similar conclusion applies to mitochondrial DNA, which is the origin of an important number of rare diseases. Mitochondria are highly susceptible to DNA mutations from ROS. Moreover, the mitochondrial DNA repair system is less sophisticated and efficient (such that mitochondrial DNA has a higher replication error rate). However, mitochondria are also involved in signaling both the nucleus and the cytoplasm; in so doing, mitochondria enhance the development of cellular adaptation.

The DNA damage theory of aging remains a powerful one. Mammalian tissues clearly accumulate different types of DNA damage with age, which may eventually have profound implications on the equilibrium between cell survival and death. DNA damage induces different cell-intrinsic checkpoints (p53, retinoblastoma, p16, p19, p21 etc.), which play a pivotal role in the control of cell proliferation, differentiation, and/or senescence and aging. A decline in stem cell function results in abnormal tissue homeostasis and repair. An increase of such abnormalities may lead to a malignant transformation phenotype.

We now know that cells respond to the injury of their genetic material not only with the DNA repair response, but also with maneuvers that help them adapt to hostile and difficult environments (e.g., those that present free radicals and/or lack of appropriate antioxidants). These adjustment mechanisms are extremely advantageous for the maintenance of cellular homeostasis and integrity. Technological and scientific advances in the field of DNA damage and repair allow one to look forward to the emergence of new diagnostic and therapeutic strategies that may be useful for better managing rare and degenerative diseases.

Prof. Guillermo T. Sáez
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 250 words) can be sent to the Editorial Office for assessment.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. There is an Article Processing Charge (APC) for publication in this open access journal. For details about the APC please see here. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.