The influence of folic acid depletion on the Nucleotide Excision
Repair capacity of human dermal fibroblasts measured by a modified Host Cell
Reactivation Assay
Affiliations: Department of Biomedical Engineering, University of
Applied Sciences, Sigmaringen, Germany | Beiersdorf AG, Hamburg, Germany
Note: [] Address for correspondence: Prof. Dr. Jörg Bergemann,
Department of Biomedical Engineering, University of Applied Sciences
Sigmaringen, Anton-Günther-Strasse 51, 72488 Sigmaringen, Germany. Tel.:
+49 7571 732 273; E-mail: bergema@hs-albsig.de
Abstract: Animal and human studies have shown that low levels of folic acid
are associated with an impaired DNA Repair Capacity (DRC) and an increased
cancer risk. However, the molecular evidence that folic acid enhances the DRC
of cultured human cells is still limited because of a paucity of in vitro
studies. We investigated the effect of folic acid depletion in vitro on
the DRC of human dermal fibroblasts derived from 17 donors of different ages.
To assess the cellular Nucleotide Excision DRC, we used a modified
Host Cell-Reactivation Assay (HCRA), adapted to the Fluorescence Activated Cell
Sorting (FACS)-technology, which is highly sensitive in comparison to
luminometer-technology and allows single cell based analysis. We used DsRed as
a reporter (irradiated with UVC light) and pEGFP to control the performance of
the transformations. Folic acid had a statistically significant effect on the DRC in all
of the 17 donors, however, the levels varied considerably between individuals
(2.0–19.6%). When the effect of folic acid substituted on the DRC was compared to
donor age, we observed that there was less DNA repair in old donors compared to
the younger donors, although this was only significant at lower levels.
Journal: BioFactors, vol. 31, no. 3-4, pp. 181-190, 2007
