Irradiation with 365 nm and 405 nm wavelength shows differences in DNA damage of swine pancreatic islets

PLoS One. 2020 Jun 25;15(6):e0235052. doi: 10.1371/journal.pone.0235052. eCollection 2020.


Introduction: 3D printing is being used more extensively in modern biomedicine. One of the problems is selecting a proper crosslinking method of bioprinted material. Amongst currently used techniques we can distinguish: physical crosslinking (e.g. Ca2+ and Sr2+) and chemical crosslinking-the UV light crosslinking causing the biggest discussion. UV radiation is selectively absorbed by DNA, mainly in the UV-B region but also (to some extent) in UV-A and UV-C regions. DNA excitement results in typical photoproducts. The amount of strand breaks may vary depending on the period of exposition, it can also differ when cells undergo incubation after radiation.

Aim: The aim of this study was to show whether and how the time of irradiation with 405 nm and 365 nm wavelengths affect DNA damage in cell lines and micro-organs (pancreatic islets).

Materials and methods: The degree of DNA damage caused by different wavelengths of radiation (405 nm and 365 nm) was evaluated by a comet assay. The test was performed on fibroblasts, alpha cells, beta cells and porcine pancreatic islets after 24 hours incubation period. Samples without radiation treatment were selected as a control group. Results analysis consisted of determining the percent of cells with damaged DNA and the tail intensity evaluation.

Results: The degree of DNA damage in pancreatic islets after exposure to 405 nm wavelength oscillated between 2% and 6% depending on the tested time period (10 - 300 seconds). However, treating islets using 365 nm wavelength resulted in damage up to 50%. This clearly shows significantly less damage when using 405 nm wavelength. Similar results were obtained for the tested cell lines.

Conclusions: Crosslinking with 405 nm is better for pancreatic islets than crosslinking with 365 nm UV light.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • DNA Damage*
  • Humans
  • Islets of Langerhans / metabolism*
  • Islets of Langerhans / pathology
  • Mice
  • Swine
  • Ultraviolet Rays / adverse effects*

Grants and funding

This study was financially supported by The National Centre for Research and Development. Grant no. STRATEGMED3/305813/2/NCBR/2017 The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.