Scratching deep beneath the surface, a team of researchers from the University of California, San Diego School of Medicine and three South Korean institutions have identified two distinct neuronal signaling pathways activated by a topical cream used to treat a variety of skin diseases. One pathway produces the therapeutic benefit; the other induces severe itching as a side effect.
The findings, published in this week's early online edition of the Proceedings of the National Academy of Sciences, point to the possibility of designing future drugs that effectively treat targeted conditions while blocking the cellular signals that can lead to problematic itching and scratching.
"This new pathway provides another avenue to block the scratching response that appears as a chronic side effect during treatments of cancer, renal failure or the use of some antibiotics," said Melvin I. Simon, PhD, an adjunct professor in the UCSD Department of Pharmacology and a corresponding co-author of the study, headed by Sang-Kyou Han, an adjunct assistant professor at UC San Diego.
Itching – and the scratching response – are part of a complex and imperfectly understood somatosensory process that includes complex, confounding psychological factors. The mechanisms involved are so sophisticated, said Simon, that just reading or thinking about itching can provoke the sensation.
Improving understanding of itch biology isn't just a matter of scratching an intellectual curiosity. It could lead to practical medical benefits, according to Simon. "Itching and scratching are side effects of a variety of therapeutic drugs and of specific illnesses. In many cases, these effects are severe and make it impossible to use otherwise effective therapies. Thus, the itch remains an unmet medical need."
In the PNAS study, the scientists focused on Imiquimod (marketed as Aldara), a prescription-based topical cream used to treat a number of skin diseases, including some forms of skin cancer, by activating the body's innate immune response. One major side effect: Imiquimod produces intense itching and scratching.
The researchers discovered that the skin sensory circuit activated by Imiquimod to causes itching is different from the signaling pathway involved in the drug's therapeutic benefit. Indeed, the Imiquimod itch mechanism is distinct from other, well-defined itch mechanisms.
"By breaking down the response and sorting out its various elements, it may be possible to both understand the molecular mechanisms involved and to control them," said Simon, who noted more research is planned.
Co-authors of the paper are Se-Jeong Kim of UCSD's Department of Pharmacology and the Department of Neuroscience, Dental Research Institute and Brain Korea21, School of Dentistry, Seoul National University; Goon Ho Park, Hyejung Min and Estelle Wall, UCSD Department of Pharmacology; Donghoon Him and Sung Joong Lee, Department of Neuroscience, Dental Research Institute and Brain Korea21, School of Dentistry, Seoul National University; Jaekwang Lee and C. Justin Lee of the Center for Functional Connectomics, Korea Institute of Science and Technology.
Scott LaFee | EurekAlert!
Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University
Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017
25.04.2017 | Laser Zentrum Hannover e.V.
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
25.04.2017 | Physics and Astronomy
25.04.2017 | Materials Sciences
25.04.2017 | Life Sciences