This topic mainly is about: Idebenone and Ferulic acid (Vitamins C+E) by
Audrey Kunin, M.D. on april 7 2005 under the name "Antioxidants investigated":
http://www.dermadoct.....C537D33BA69D}
Recently we have seen not one, but two new antioxidants enter the skin care arena, each trying to lay claim to the title of "best" new rejuvenator. Are they really the best? What's fact, what's fiction? Let's look at the hurdles faced by each new competitor to find out which one deserves a spot in the medicine cabinet.
We all know that ultraviolet light is bad for our skin. It can cause sunburn, wrinkles and skin cancer. Yet how does this actually occur? As UVB hits the skin, and a chemical reaction called oxidation occurs within skin cells. Unstable free radicals are formed which then damage cellular DNA. How can this be stopped? Simple. Prevention is made possible by antioxidants and every day use of a broad-spectrum sunscreen.
What exactly is an antioxidant? According to the Merriam-Webster dictionary, an antioxidant is "a substance that inhibits oxidation or reactions promoted by oxygen or peroxides."
Antioxidants are ubiquitous-they can come from many sources. Some are vitamins like C and E, others minerals such as GHK copper peptides and selenium. There are enzymes (including superoxide dismutase), nutrients (like ubiquinone) and phytochemicals such as N-6 furfuryladenine, white tea and ferulic acid. And they can work in different ways. However, no matter their origin or function, in the simplest sense, antioxidants work to neutralize free radicals thus reducing cell injury.
How does one measure how well an antioxidant functions? Three major measurable events occur related to light-induced injury.
- Sunburn (Erythema)
- Sunburn Cell Formation
- Thymine Dimer Formation
Testing a product or ingredient's ability to increase the MED required to cause redness is one way to demonstrate photoprotection. An initial MED will vary by individual. Once determined, one can see if the topical application of an antioxidant successfully prevents photodamage by seeing if the MED increases. A rise in the MED means it takes more UV light than typically anticipated to produce that sunburn. Two MEDs for instance, suggests it takes twice the expected amount of light to cause visible redness to form. Four MEDs, is 4X the light typically required.
Measuring the number of sunburn cells is another method of evaluating the effectiveness of a topical antioxidant. The presence of fewer sunburn cells suggests more protection against ultraviolet light.
Sunburn Cell Formation is determined microscopically. Ultraviolet light exposure leads to sunburn and essentially some epidermal cells shrivel up and die. These dead cells (sunburn cells) are both visible and countable when light-treated skin is biopsied and examined under the microscope.
Finally, on a molecular level, UV light causes cellular DNA damage, which is demonstrated by the formation of a byproduct of this damage, thymine dimers. Under normal circumstances the human body can repair the damage. When the level of damage exceeds the body's ability to perform these repairs, skin cancer can result. Measuring the level of thymine dimers is one way to access the severity of UV-induced damage.
In order to have an excellent ability to prevent photodamage, an ingredient or in real life, a commercially available formulated product must increase the amount of light necessary to cause skin redness and reduce the level of DNA damage (as measured by the level of thymine dimers formed) plus there must be a reduction in the number of skin cells which die in response to light exposure.
This is what makes an antioxidant special and vital in skin rejuvenation and photoprotection. The better the antioxidant can perform these tasks, the better the antioxidant is suited for skin rejuvenation use.
I go into all this with its scientifically boring detail because it is important to truly understanding and scrutinizing the studies we're about to look at.
Idebenone
A close cousin to Ubiquinone, otherwise known by the name co-enzyme CoQ 10, Idebenone has been the most hyped antioxidant entry into the skin rejuvenation market in years. First presented as a poster at the February 2004 annual American Academy of Dermatology meeting, the buzz the followed was enormous. After all, compared to 5 other widely known, and used, antioxidants, Idebenone apparently outperformed the others in all categories of effectiveness. Or did it?
It's been more than a year now since Allergan presented their poster at the American Academy of Dermatology meeting introducing a unique antioxidant promising to be the ultimate anti-aging ingredient Idebenone.
I have obtained a full copy of the study: Antioxidants Compared In A New Protocol To Measure Protective Capacity Against Oxidative Stress-Part II (DiNardo, Lewis, et al.; presented at the American Academy of Dermatology meeting; February 6-11, 2004; Washington, D.C.) and think it is worth taking a closer look. Particularly since yet another new antioxidant-chocked product, SkinCeuticals C E Ferulic has also just hit the market.
Despite the hype, science is the bottom line. What was widely known a year ago was the table noted below cited in the scientific poster.
Test Idebenone Tocopherol
(Vitamin E) Kinetin
(N-6 Furfuryladenine) Sunburn Cell Assay 20 16 11 Photochemiluminescence 20 20 10 Primoary Oxidative Products 16 10 20 Secondary Oxidative Products 19 17 10 UVB-Irradiated Keratinocytes 20 17 17 Total Points 95 80 68 Test Ubiquinone
(CoQ10) Ascorbic Acid
(Vitamin C) Alpha Lipoic Acid Sunburn Cell Assay 6 0 5 Photochemiluminescence 15 20 5 Primoary Oxidative Products 5 3 4 Secondary Oxidative Products 12 12 20 UVB-Irradiated Keratinocytes 17 17 7 Total Points 55 52 41
Okay – each category had a high possible number of 20. Add the 5 categories together and the best score possible was 100 points. None of the antioxidants hit this, but you can see that Idebenone totaled 95 while alpha lipoic acid only managed a score of 41 points.
Based upon these results, it certainly seems obvious that Idebenone wins hands down against the others. And I must say, that the excitement level in the dermatology community (not to mention the scores of excited magazine articles buzzing about it) was amazing. After all, it's not every day a new fabulous antioxidant is born!
Or so we thought. Not to take everything away from Idebenone. It's unquestionably a welcome newcomer to skin rejuvenation. But now a closer look at the actual study brings up some questions.
The study states that all of the ingredients tested were at 0.5% concentrations. While that sounds like an even playing field, think about it. Kinerase (a brand of N-6 furfuryladenine) is marketed as a physician-strength level at 1.0%. L-ascorbic acid, a well-studied form of Vitamin C in skin rejuvenation (such as SkinCeuticals and Cellex-C) tends to best perform at levels ranging between 10-20%. Alpha Lipoic Acid is formulated at levels ranging from 3-5%. Does using suboptimal levels of ingredients truly prove they are less beneficial than Idebenone? Also, what about the results for Idebenone? Why is the "medical" strength 1% used in Prevage necessary, if the 0.5% was ideal?
What about the real world? Who's applying straight idebenone, or any of these other ingredients to the skin? In dermatology, a medication is only as good as its base; the active ingredient doesn't function in a bubble. The pH of a formulation, the type of vehicle, the other actives present in the product and many other variables all ultimately play a role in product effectiveness. The study took the sole ingredient and mixed it in a water and alcohol base. There's no mention of how this may have boosted or adversely affected ingredient performance.
C E Ferulic Acid
We all know and love Vitamin C. After all, L-ascorbic acid has long been shown to be a wonderful antioxidant capable of stimulating fibroblast activity. Vitamins C and E work synergistically. Vitamin C is water soluble, working hard within the cell while Vitamin E is lipid soluble, helping stabilize the cellular membrane against free radical damage.
So let's look at the other newcomer, C E Ferulic Acid. What do you get when you mix a few beloved vitamins together and throw in a new botanical antioxidant? Well, when it comes to C E Ferulic Acid, apparently the answer is eight times anticipated photoprotection. A little known botanical, ferulic acid is an antioxidant that strives to more than maximize the antioxidants it plays with in the new SkinCeuticals C E Ferulic. Composed of 15% Vitamin C, 1% Vitamin E and 0.5% Ferulic Acid, is it the great rejuvenator we've all hoped for?
First, ferulic acid has been shown to stabilize a solution of Vitamins C and E. Remember oxidation? Tired of your Vitamin C serum discoloring when exposed to air? Ferulic acid helps reduce this issue. Here´s what C E Ferulic claims to do:
- Sunburn cell formation is reduced by 96%.
- Thymine dimer formation is prevented.
- Photoprotection is elevated 8 times.
Product A Prevage 1% Idebenone
Product B True 0.5% Idebenone
[C E Ferulic prevented the formation of erythema even at levels of UV exposure exceeding 8 MEDs, therefore providing 8x photoprotection. Due to resulting erythema after exposure of 2 and 4 MEDs, other technologies were not tested at higher levels of UV exposure.]
[C E Ferulic reduced the formation of sunburn cells up to 96% at 2 MEDs of UV exposure. In a separate study, Idebenone was shown to reduce the formation of sunburn cells by 38% at 1.5 MEDs of UV exposure.]
How do you read these graphs and what is their significance? In graph 1, the MED is significantly elevated for C E Ferulic to 8x MED.
In descending order of MED Photoprotection from best to worst:
C E Ferulic
Product A 1% Prevage*
Product B True*
1% Idebenone
1% Ubiquinone (CoEnzyme Q10)
Control
*Note that at higher MEDs, True actually performed better than Prevage preventing erythema. This is hypothesized to be due to the actual cosmetics pigments adding some added physical blocker benefit.
In the second graph, sunburn cell reduction was evaluated. In descending order of effectiveness from best to worst:
SkinCeuticals C E Ferulic contains 15% Vit C, 1% Vit E, 0.5% FA
SkinCeuticals C + E contains 15% Vit C, 1% Vit E
Vitamin C 15%
Vitamin E 1%
Idebenone 0.5%
It is truly fascinating seeing the differences when clinically effective levels of ingredients and formulations are tested against each other. C E Ferulic Acid outperforms Idebenone in both the MED and sunburn cell assays.
So what do we make of this? The skin rejuvenation landscape is rapidly changing and so does our thinking in response to new launches. Science is going to be ever more important to help guide us in our decision-making. According to the studies above, SkinCeuticals C E Ferulic outperformed idebenone.
And of course, no antioxidant, regardless of its photoprotective abilities, replaces sunscreen. Certainly antioxidants like green tea extract and Vitamin E are being added to sunscreen to provide further photoprotection. Apply an SPF 30 with maximum UVA protection daily to achieve appropriate protection no matter what your antioxidant rejuvenator of choice.
See also:
http://www.imminst.o...showtopic=20382
Attached Files
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Idebenone.pdf 749.1KB
83 downloads
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Topical_idebenone_photodamaged_skin.pdf 246.75KB
140 downloads
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Compare_to_Idebenone.pdf 125.46KB
168 downloads
Edited by Eva Victoria, 14 February 2008 - 06:02 PM.
