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Skin Wrinkles. Sun damage causes wrinkles. The Sun. Wrinkled skin. Protection. T reatment. Skin proteins ( Elastin , collagen). The Sun. Wrinkled skin. UV: Large amounts kill cells Small amounts damage a cell’s DNA (gene mutations). UV radiation EM radiation
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Skin Wrinkles Sun damage causes wrinkles
The Sun Wrinkled skin Protection Treatment Skin proteins (Elastin, collagen)
The Sun Wrinkled skin UV: Large amounts kill cells Small amounts damage a cell’s DNA (gene mutations) UV radiation EM radiation Ionizing radiation break particles into ions free radicals are produced Protection Treatment Wearing clothes and sunscreen to absorb the UV Moisturise Anti-oxidants Specific skin creams and serums Staying out of the sun in the shade ALARA – reduce the risk as low as reasonably acceptable UV breaks down collagen and reduces synthesis of new collagen Collagen and elastin are structural proteins Proteins can be enzymes or structural proteins Genes are the codes for the body to make proteins. Skin proteins (Elastin, collagen)
Other external factors involved in skin wrinkling • Facial Expressions – lines develop as skin ages and loses its elasticity • Gravity – in your fifties elasticity declines dramatically – tip of nose droops, eyelids fall, jowls form • Sleeping position – over years sleep lines develop into wrinkles due to position of face on your pillow • Smoking- 10 years of smoking gives more deeply wrinkled and leathered skin than in non-smokers
Your genes also contribute to ageing • Genes control how quickly normal ageing occurs • Many different genes are involved • Genes for the structural proteins collagen, elastin fibrillin • Genes for enzymes that make collagen, elastin fibrillin • Genes for melanin – naturally browner skins age less rapidly • Genes for enzymes that repair DNA damage
Design an experiment to test a new face cream • You have to decide: • Will you test it on people straight away? • What testing methods are normally used on new medicines?
Design a good trial • What age group will you test it on? Why? • Gender? Why? • Number of people. Explain your decision • Do you need a control group? If so what will you use on them? Explain your decision • How long will you test it for? • What will you measure? • How will you know if it is effective?
Improve your trial • How should you choose the people? • Are there any confounding variables that can be controlled? • Who should conduct the experimental trial? • Should the people in the trial know if they are getting the test cream or a placebo? • Should the assessors know who had the test cream?
Reliable and Accurate? • How could the results be made more reliable? • Could your study be made more accurate? • How could you get the public to believe your results?
Another way to test? • Would it be sensible to test the two different creams on different sides of one person’s face? • Give reasons for and against: For: The genetic and environmental background of each individual would be the same. The same skin type and previous damage. Against: The individual might mix up the creams and make the test invalid. There might be large differences in the effectiveness of the creams which would not be helpful to the individual.
A different study on anti-ageing cream In a double-blind study, a topical vitamin C complex was applied to one half of the face and a placebo gel to the opposite side. Clinical evaluation of wrinkling, pigmentation, inflammation, and hydration was performed prior to the study at weeks 4, 8, and 12. The results showed a statistically significant improvement of the vitamin C-treated side, with decreased photoaging scores of the cheeks and the perioral area. The peri-orbital area improved in both the vitamin C and placebo-gel group, probably indicating improved hydration. The overall facial improvement of the vitamin C side was statistically significant. Biopsies showed increased collagen formation in the vitamin C group. This study showed that topically applied vitamin C results in clinically visible and statistically significant improvement in wrinkling when used for 12 weeks. This clinical improvement correlated with biopsy evidence of new collagen formation (Fitzpatrick et al. 2002).In response, cosmetic companies have increased the percentages of active ingredients with the goal of replicating the antiaging effects revealed in the published studies. The problem of increasing the level of active ingredients is that the wrong layers of the skin can be overly saturated resulting in irritation and reduced efficacy. The first step in resolving this problem is to encase the active ingredients so that they can be absorbed through the top layer into the lower layers of the skin where they are most active. The second step is to design a delayed release system so that the active ingredients can be released over an extended amount of time.
Anti-wrinkle cream “Public understanding of Science” in the media and advertising Biology B7 Pre-Release 2011
1. Scientists thought that the new cream was an improvement on other anti-wrinkle cream. What was their evidence? • …………………………………………………………............…. • 2. What is a scientific study? • ………………………………………………………………….…. • 3. The results were published in a medical journal. What does this suggest? • ……………………………………………………………………..... • 4. How much better is the new cream than other creams – as a percentage? • ………………………………………………………………………… A study found people who used the cream for a year had fewer wrinkles. The wrinkles were also smaller. A study where an investigation is carried out, controlling other factors to make the test fair and accurate and where the conclusion is based on sufficient results so that it is reliable. The results of the study will have been peer-reviewed before being published in a Medical Journal. 100% . This is the same as “twice as good”.
5. The ingredients in the cream increased the production of fibrillin in the skin. Suggest what type of protein fibrillin is? • …………………………………………………………............…. • 6. Why did the cream not just contain fibrillin? • ………………………………………………………………….…. • 7. The lupin extract increases the production of the protein fibrillin. Suggest how this might happen. • ……………………………………………………………………..... • 8. What unexpected side effects might occur? • ………………………………………………………………………… A structural protein like elastin. (Or perhaps an enzyme that allows more protein synthesis of elastin or reduces break down of elastin) Fibrillin is a protein so it is too large to enter a cell across a cell membrane. Skin needs human fibrillin and this cannot be made from plant extracts or from genetically modified organisms. The extract might switch on inactive genes on in the skin cells. Or it might inhibit the breakdown of fibrillin. Other genes might also start to produce other proteins at higher levels.
9. Why is it important that the research was unbiased? • …………………………………………………………………….. • 10. Was the research conducted in an unbiased manner? • …………………………………………………………............…. • 11. How could the professor show that his research was unbiased? • ………………………………………………………………….…. • 12. Can you conclude that the cream is effective? • ……………………………………………………………………..... • 13. What role did the media play in the promotion of this cream? • ………………………………………………………………………… Bias might give unfair results or conclusions. Maybe not: - The professor was funded by the manufacturer. He might get further funding if he published the “right results” that the manufacturer wanted Probably: - He designed the tests independently. He could get agreement to publish his findings whichever result he found. He used the same methods approved for testing new medicines Yes - The cream was effective in most people (70% of people). No – The cream was not effective in 30% of people. The manufacturer advertised the good results of the scientific study to the public.
14. What evidence is there that these claims are not just false claims? • …………………………………………………………………….. • 15. Would the cream only remove 70% of Wendy’s wrinkles? • …………………………………………………………............…. • 16. Would Sue get even better results by using twice as much? • ………………………………………………………………….…. The claims are based on independent research using correct scientific procedures. The trial should have been randomised and double blind but we are not given this information. No ,this means that there is a 30% chance it would not work, but a 70% chance it would work. This has not been tested so there is no evidence to support this idea. There may be risks involved in using too much.
17. The new cream is twice as good as normal anti-wrinkle creams but the new cream was found to be effective in 70% of the people who tested it. What does this tell you about the effectiveness of normal anti-wrinkle creams? …………………………………………………………………….. 18. Is the method of measuring the effectiveness of the new cream accurate? …………………………………………………………............…. Normal anti-wrinkle creams are only half as effective as the new cream so they must be effective in 35% of the people who used it. There is no information given. Asking the individuals their opinion is subjective and non-quantitative so less accurate. Using trained dermatologists to make judgements and take measurements would make the results more accurate.
Further Information • See next slides and BBC news 2009 pdf
Funding of this research. • Professor was ‘independent’ but research was funded by company (Boots’) • Is this true independence? • The results would have been published either way. • Is he more likely to report something favourable to company sales because this might get him more work? • Why is it important to be independent? • To reduce the risk of bias that might give unfair results or conclusions.
How are new medicines tested? • 1. On human cells • 2. On animals • 3. On human volunteers • A test group and a control group (having a placebo). • Blind test or double blind test (neither patient nor member of the research team knew who had which cream) • Both groups should be chosen randomly and of the same type of people eg those with sun damage aged 45-80 • Large sample size is needed for results to be reliable. • The results can be tested for statistical significance.
What measurements were done? • Fibrillin levels test • Test each individual before starting the trial for base levels of fibrillin • Test again at end. (Skin biopsy from wrist) • Wrinkles test • Advanced clinical assessments by dermatologists comparing before and after.
How are results published? • Researcher checks the experimental design and the results. • Submits his paper to a scientific journal. • Independent scientists have to “peer review’ the work – they critically evaluate the study. • The Paper gets accepted and is published in the British Dermatological Journal • Other scientists repeat the research to see if the same results are found, or do related work to see if other results support the findings of the first study.
Testing active ingredients • How could you test which ingredient increased the production of fibrillin in the skin? • Test each active ingredient on tissue culture cells with a negative control (some neutral carrier with not active ingredient) • Test each ingredient in an aqueous cream on individuals and compare to others with aqueous cream but no active ingredient. • Combinations of ingredients may have to be tested.
