Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

DNA repair could reduce sunburn

27.11.2001



An immune system chemical may undo skin damage by sunlight.

A chemical involved in immune-system signalling may be able to reverse some types of skin damage caused by sunlight. It could reduce sunburn by activating DNA-repair mechanisms, a new study suggests, raising the possibility that the chemical might be used to prevent or treat skin cancer1.

High-energy ultraviolet light is thought to promote skin cancer by damaging the DNA within cells. Skin cancer, the most common malignancy among people of Western European descent, strikes over one million people each year in the United States alone.



But when cultured human skin cells were treated with the protein interleukin-12 (IL-12), they were less likely to incur permanent DNA damage or die after being exposed to ultraviolet light, the researchers found. The cells showed as much damage as control cells immediately after exposure, but had significantly less damage several hours later. The same effect was found in the skin of mice treated with IL-12 before being exposed to ultraviolet. This suggests that IL-12 promotes repair rather than blocking ultraviolet rays, as most sunscreens do.

The protein appears to stimulate a cellular editing system that snips damaged pieces of DNA out of the sequence, explains Thomas Schwarz of the University of Münster in Germany, a member of the team that carried out the study.

IL-12 could be a "very attractive" treatment for sun damage, says Schwarz, but it will never take the place of sunscreens, he cautions.

While they are still the best defence against skin cancers, sunscreens are never 100% effective says Julia Newton Bishop, who studies melanoma at St James’s Hospital in Leeds, UK. "So we’re always interested in mechanisms to reduce damage or speed repair."

IL-12 may protect skin by sparking an "SOS response", suggests Barbara Gilchrest, who studies DNA repair at Boston University School of Medicine. Bacteria have long been known to throw their DNA repair system into a higher gear after being exposed to sunlight, so that later exposures are less damaging; in recent years, mammalian skin cells have been found to do the same.

IL-12 is produced after exposure to sunlight, Gilchrest says. Adding it to cells before exposing them to ultraviolet light could "trick the system into thinking it has already seen sun damage so it should get ready," she says.

Damage limitation

IL-12 is not the first chemical found to promote DNA repair after ultraviolet damage. Earlier this year, researchers showed that a bacterial enzyme placed on the skin prevents the formation of new cancerous regions in people highly prone to skin cancer.

But unlike the bacterial enzyme, IL-12, being naturally produced by human cells, would be less likely to trigger allergic responses says Kenneth Kraemer, who works on DNA excision at the National Institutes of Health in Bethesda, Maryland. More work is needed to clarify IL-12’s effects and possible side effects, he adds, but the idea that it could be used as a therapy for skin cancer is "provocative".

IL-12’s protective function is a surprise. It belongs to a class of signalling chemicals called cytokines, which were never suspected of being able to stimulate DNA repair.

The work "opens up a whole new area of investigation," says Kraemer. If IL-12 is involved in DNA repair, he says, other cytokines may be as well. "This is probably the tip of the iceberg."

References

  1. Schwarz, A. et al. Interleukin-12 suppresses ultraviolet radiation-induced apoptosis by inducing DNA repair. Nature Cell Biology, Advance Online Publication, 26 November (2001), DOI: 10.1038/ncb717
  2. Yarosh, D. et al. Effect of topically applied T4 endonuclease V in liposomes on skin cancer in xeroderma pigmentosum: a randomised study. Lancet, 357, 926, (2001).


ERICA KLARREICH | © Nature News Service
Further information:
http://www.nature.com/nsu/
http://www.lancet.com

More articles from Health and Medicine:

nachricht Inselspital: Fewer CT scans needed after cerebral bleeding
20.03.2019 | Universitätsspital Bern

nachricht Building blocks for new medications: the University of Graz is seeking a technology partner
19.03.2019 | Karl-Franzens-Universität Graz

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

Open source software helps researchers extract key insights from huge sensor datasets

22.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>