The biological mechanism of sunburn – the reddish, painful, protective immune response from ultraviolet (UV) radiation – is a consequence of RNA damage to skin cells, report researchers at the University of California, San Diego School of Medicine and elsewhere in the July 8, 2012 Advance Online Publication of Nature Medicine.
A photomicrograph of superficial keratinocytes or skin cells. Credit: Thomas Deerinck, National Center for Microscopy and Imaging Research, UC San Diego.
The findings open the way to perhaps eventually blocking the inflammatory process, the scientists said, and have implications for a range of medical conditions and treatments.
"For example, diseases like psoriasis are treated by UV light, but a big side effect is that this treatment increases the risk of skin cancer," said principal investigator Richard L. Gallo, MD, PhD, professor of medicine at UC San Diego School of Medicine and Veterans Affairs San Diego Healthcare System. "Our discovery suggests a way to get the beneficial effects of UV therapy without actually exposing our patients to the harmful UV light. Also, some people have excess sensitivity to UV light, patients with lupus, for example. We are exploring if we can help them by blocking the pathway we discovered."
Using both human skin cells and a mouse model, Gallo, first author Jamie J. Bernard, a post-doctoral researcher, and colleagues found that UVB radiation fractures and tangles elements of non-coding micro-RNA – a special type of RNA inside the cell that does not directly make proteins. Irradiated cells release this altered RNA, provoking healthy, neighboring cells to start a process that results in an inflammatory response intended to remove sun-damaged cells.
We see and feel the process as sunburn.
"The inflammatory response is important to start the process of healing after cell death," said Gallo. "We also believe the inflammatory process may clean up cells with genetic damage before they can become cancer. Of course, this process is imperfect and with more UV exposure, there is more chance of cells becoming cancerous."
Gallo said it's still not known how gender, skin pigmentation and individual genetics may affect the mechanism of sunburn. "Genetics is closely linked to the ability to defend against UV damage and develop skin cancers," he said. "We know in our mouse genetic models that specific genes will change how the mice get sunburn. Humans have similar genes, but it is not known if people have mutations in these genes that affect their sun response."
Jamie J. Bernard is currently at the Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers University. Other co-authors are Christopher Cowing-Zitron, Teruakai Nakatsuji, Beda Muehleisen, Jun Muto, Andrew W. Borkowski and Benjamin D. Yu, Division of Dermatology, UC San Diego; Laisel Martinez, Miami Veterans Affairs Medical Center; and Eric L. Greidinger, Miami Veterans Affairs Medical Center and Division of Rheumatology, University of Miami Miller School of Medicine.
Funding for this research came, in part, from National Institutes of Health grants R01-AR052728, R01-A1052453 and R01-A10833358, a Veteran Affairs Merit Award, National Institute of Environmental Health Sciences Training Grant ES007148 and NIEHS Center Grant ES005022, Department of Veterans Affairs, NIH AR48805 and the Lupus Research Institute.
Scott LaFee | EurekAlert!
Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University
How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy