Virtual skin model reveals secrets of skin aging
We constantly grow new skin and slough off the old. Until now, scientists have never agreed on exactly how this works, but new research from the University of Sheffield may provide the answer.
Engineers and biologists at the University of Sheffield have shown how a recent theory-- that skin has 'sleeping' stem cells which can be woken up when required-- best explains how our skin constantly regrows. The research-- conducted in collaboration with The Procter & Gamble Company (P&G), makers of Olay, and published in Nature Scientific Reports-- has implications for combating the effects of aging and perhaps even skin cancer.
The Sheffield/P&G team developed an "in silico" (computer) model of human skin biology, capturing how the outer layers of the skin are developed and maintained over time. This model simulation or "virtual" skin was then used to test the three most popular theories of how skin cells function to regenerate our skin, the largest human organ, over a three-year period. When the simulation was run according to two of the theories, the virtual skin failed to fully regenerate. Only one theory enabled the virtual skin to still be in good shape after three years, as Dr. Xinshan Li (University of Sheffield Faculty of Engineering) and Dr. Arun Upadhyay (P&G), the lead co-authors explained in their research.
"The theory which seems to fit best says that skin has a population of 'sleeping' stem cells, which sit in the lowest layer of the skin but don't constantly divide to make new cells," Dr. Li said. "However, these sleeping cells can be called into action if the skin is damaged, or if the numbers of other types of more mature skin cells decrease, ensuring that the skin can be constantly regenerated under all conditions."
The model showed that we gradually lose these sleeping stem cells over time-- which would explain why our ability to regenerate our skin reduces as we age. "Each time we wake up these cells, to heal a wound or replenish stocks of other cells, a few of them don't go back into sleep mode, so the population slowly reduces," says Dr. Li. "This explains why older skin is slower to heal and in part why our skin changes as we age. By understanding this mechanism better, it might be possible to find ways to combat the effects of aging on our skin."
Computer modelling of skin biology is the latest step in the evolution of skin science. It allows scientists to project the activity of tissues like skin that are difficult to follow in live systems for extended periods. Currently, 3-dimensional cultures of engineered human skin are viable for only a few weeks and clinical studies in humans are only practical for a few months. With the development of in silico models scientists can predict for the first time what happens in skin as it ages year by year even as it ages decade by decade.
"These models permit exploration of hypotheses in very short periods of time, relative to the lab based bench work," says Dr. Upadhyay. "In silico modelling can significantly shorten R&D programs, and help focus subsequent lab or clinical work on the options with the greatest likelihood of succeeding. This is another reason why in silico models are an effective complement to more established research tools and methods."
The ability to follow virtual skin models over decades may be especially important to skin cancer research. Environmental damage caused by UV exposure or chronic wounding can cause sleeping cells to harbor the mutations which cause skin cancers such as basal cell carcinoma, a very aggressive type of skin cancer.
"The stem cells can harbor mutations throughout the years, but with no effect if they're still in sleep mode," explains Dr. Li. "However, when they start to divide to heal a wound for example, this could trigger the cancer. If it's possible to study this phenomenon for long periods of time it may be possible to find ways to prevent the activation of mutated cells and therefore reduce the risk of developing the disease."
Other parts of the body, such as the lung or gut lining and the cornea, also regenerate in the same way as our skin. Research is already underway at the University of Sheffield to look at the healing process of the lung lining following asthma attacks.
This study is an excellent example of how computer modelling can enhance our long-term understanding of complex processes such as skin aging. Dr. Upadhyay, a physicist-turned-computational biologist, drew inspiration from the great physicist Richard Feynman in summarizing the study, noting that, "You really don't understand something until you have built it from scratch. By building the virtual skin model from a few cells into a tissue capable of self-renewal, we have moved a big step in our understanding of stem cells and skin renewal."
X. Li, A. K. Upadhyay, A. J. Bullock, T. Dicolandrea, J. Xu, R. L. Binder, M. K. Robinson, D. R. Finlay, K. J. Mills, C. C. Bascom, C. K. Kelling, R. J. Isfort, J. W. Haycock, S. MacNeil & R. H. Smallwood (2013) “Skin Stem Cell Hypotheses and Long Term Clone Survival – Explored Using Agent-based Modelling”. Nature Scientific Reports 3, Article number: 1904 doi:10.1038/srep01904
Working backward: Computer-aided design of zeolite templates
Rice scientists apply drug-design lessons to production of industrial minerals
Taking a page from computer-aided drug designers, Rice University researchers have developed a computational method that chemists can use to tailor the properties of zeolites, one of the world's most-used industrial minerals.
The research is available online and will be featured on the June 21 cover of the Royal Society of Chemistry's Journal of Materials Chemistry A. The method allows chemists to work backward by first considering the type of zeolite they want to make and then creating the organic template needed to produce it.
The findings are the latest from the laboratory of Michael Deem, Rice's John W. Cox Professor of Bioengineering and professor of physics and astronomy. Deem's group has previously identified the zeolites best-suited for removing carbon dioxide from power plant exhaust, and they have also used supercomputers to create a database of potentially synthesizable zeolites -- some 2.6 million in all.
In the new study, Deem and co-authors Ramdas Pophale and Frits Daeyaert created a computational procedure to identify small organic molecules that can be used to synthesize zeolites.
"We began working on this three years ago," Deem said. "It's basic research, and we illustrated it by applying it to known zeolites. The approach could be used by industry to produce new types of zeolites."
Zeolites are common minerals. About 40 varieties occur naturally, and there are more than 150 man-made types. All zeolites are made of silicon, oxygen and aluminum, but the atomic arrangement of the three varies slightly in each type. These subtle molecular differences lead to significant variations in the chemical properties of each zeolite. As a result, several million tons of zeolites are used each year in processes such as refining of petroleum into gasoline or separation of air into oxygen and nitrogen and products as diverse as cat litter, cement, laundry detergent, water filters, animal feed and chemical separators.
Several million tons of natural zeolites are mined globally each year, but industry also uses a number of synthetic varieties. Producers create these in large process tanks.
"The silicon is either in a gel or in solution, and it condenses to make the zeolite crystal," Deem said. "The current thinking is that the crystal nucleates from an amorphous cluster of silicon oxide that's maybe 3-5 nanometers in size. Once the nucleus of the crystal forms, it continues to grow, and producers regulate the crystalline pattern by including organic molecules in the original solution."
These molecules are called "organic structure directing agents," or OSDAs. The zeolite crystal grows around the OSDAs. Intense heat is used to burn away the OSDAs and open the pores that give the zeolite its characteristic chemical properties.
In the new study, Deem, Pophale and Daeyaert created a procedure for designing OSDAs that would make a particular type of zeolite.
"We begin with a library of organic fragments -- molecules that you could buy from a chemical supplier," Deem said. "Next, we have the computer apply a range of chemical reactions to each of the molecules in the library to build up an OSDA from these individual fragments. We then evaluate each candidate OSDA based upon a number of criteria. For example, is it easy to synthesize? Is it stable in solution? Can it withstand the conditions in the zeolite production vessel? How well, energetically, does it stabilize the zeolite?"
Deem said the method was designed to be practical for industry.
"Our inspiration for this is what people have done in drug design," he said. "Drug designers learned the hard way that they could build perfectly shaped molecules, atom by atom, but that it was completely impractical to produce those ungainly molecules in bulk. As a result, they pioneered this idea of searching whole libraries of known compounds and feasible reactions to find drugs that are both efficacious and practical to produce. There are at least 55 drug candidates that have been discovered by this approach."
Deem's new method for designing OSDAs is similar, and he hopes it may one day allow researchers to produce one of the 2.6 million theoretically possible zeolites that his group identified in its 2011 study. For example, the crystalline structure of some zeolites features a chiral, twisting pattern that can be either right- or left-handed. The resulting zeolite crystals are mirror opposites. Researchers can make mixtures of these materials today, but they can't make pure right-handed or left-handed crystals. With Deem's new method, it may be possible to create an OSDA to make only left- or right-handed varieties.
"Breaking that chiral symmetry would be very exciting," Deem said. "It would highlight the broad range of possibilities of this OSDA design method."
A Handbook for Aromatherapy Practice
by Jennifer Peace Rhind
This revised and expanded new edition of the handbook provides a complete information on the use of essential oils in the fiels of contemporary aromatherapy, based on the research evidence behind their therapeutic applications.
The author provides the historical and cultural context for our understanding of aromatherapy, with an overview of its relationships with Greek, Chinese and Ayurvedic medicine. She gives a detailed account of how essential oils are created, how and where aromatherapy is used, the underlying pharmacology, and the current research. The characteristics of over 100 essential oils, absolutes and resinoids are provided in detail, including botanical and chemical information, usage and combinations.
The book is sound, has a good scientific and technical basis, it is extremely well organised and written in an extremely clear way: a really very interesting reading for everyone. The glossary as well as a series of appendices makes out of this handbook an extremely precious tool for the all students and practitioners of aromatherapy and related disciplines, as well as anyone interested in the use of essential oils for health and well-being. A complete and up-to-date bibliography completes the handbook and represents a precious source of further information for all those who want to expand their knowledge on specific topics.
Jennifer Peace Rhind is a Chartered Biologist with a Ph.D. in Mycotoxicology from the University of Strathclyde. Her long-standing interest in Complementary and Alternative Medicine (CAM) has led to qualifications in massage, aromatherapy and reflexology, and for thirteen years she worked as a therapist and partner in a multidisciplinary complementary healthcare clinic. During this time she became involved in CAM education in the private sector and co-founded the first professionally accredited CAM school in Scotland. She was a lecturer on the B.A. (Hons) Complementary Healthcare programme at Edinburgh Napier University for fourteen years, and remains involved in scent education. She lives in Biggar near the Scottish Borders.
Essential Oils. A Handbook for Aromatherapy Practice. 2nd edition
By Jennifer Peace Rhind. 2012, Paperback?ISBN: 978-1-84819-089-4
UNIPRO CHANGES NAME TO “COSMETICA ITALIA”
The Stakeholders’ Meeting of UNIPRO approved the passage of the name of the Italian Association of cosmetic companies (UNIPRO) “Cosmetica Italia”. The revision of the naming has been foreseen by the three-years program of the Presidency of the association to improve the perception of the level of reputation of the cosmetic industry and its national association representing it as explained by the President Fabio Rossello. Over the past decade UNIPRO has redefined its strategies, becoming an all-round association representing the Italian cosmetic industry internationally, with the increase of the market share in Europe, the authority of the analysis of the Study and professionalism in carrying out the activities' of Public Affairs. The new name, clearly evocative of the cosmetic industry, has the task of transmitting efficiently all changes that have occurred during the history of the association from 1967 (when the association was called the National Union of perfumery, cosmetics, toilet soaps and the like industries - UNIPRO) to today.
SUSTAINABLE BEAUTY AWARDS TO RECOGNISE GREEN ACHIEVEMENTS
The first-ever awards dedicated to sustainability in the beauty industry have been launched by Organic Monitor. The inaugural Sustainable Beauty Awards has opened for nominations, with winners to be announced at an evening reception in Paris on October 21st. The aim of the awards is to give recognition to cosmetic and ingredient firms who are pushing the boundaries of sustainability in the beauty industry. There is no charge for making nominations to the Sustainable Beauty Awards, however to be eligible cosmetic / ingredient / packaging firms / related firms must be making a difference in sustainability. The finalists for each category will be selected on 1st October, and the winner at a drinks reception at the Paris Marriott Champs-Elysées on 21st October. The awards reception will take place alongside the European edition of the Sustainable Cosmetics Summit (www.sustainablecosmeticssummit.com). Winners and finalists will benefit from media coverage and industry recognition of their sustainability achievements. The Sustainable Beauty Awards have been launched to reflect the growing importance of green issues in the cosmetics industry.
SPECTRASTAT L-SERIES BY INOLEX
Inolex presents its new Spectrastat L-Series. These are the latest addition the Spectrastat line of alternative preservatives that contain the revolutionary biostatic agent, CHA. The new systems offer wet wipes brands and converters the opportunity to meet consumer needs for products that are free of traditional biocides, such as parabens and formaldehyde donors. Daniel Winn, head of business development at Inolex refers: “We listened closely to the wet wipes industry. Their formulations have microbial difficulties that go beyond what one finds in typical personal care products […] Our new systems prove that CHA technology is an effective option for challenging wet wipes applications”.