Dr. Pickart, thanks for answering my questions. I feel like, the more I read about your articles, the more questions I have.

What about Tri-peptide?

It depends on which three peptides.

This message has been edited. Last edited by: JW,

Not sure ... I found it listed as one of the ingridients in SK-II products.

JW, I read one of your questions on other thread about Hayflick Limit. I have posted a question about the possibility that our skin would eventually become immune to even the strongest SRCP in long term use, but haven't got any answer on it. I wonder if you could probably help answer my question. Tx..

This message has been edited. Last edited by: learnmore,

Sorry to butt in, but that's an interesting question to ponder.

Wouldn't an 'immunity' to SCRP really mean either a complete resistance to it, and how could said resistance actually happen, since skin is a semi-permeable membrane regardless of how thick it gets? (If that were the case SCRP's wouldn't work so well on my cracked heels!)

Or would it mean that the skin has reached it's saturation point for a particular component, in which case one would only have to wait a while before taking some more? Kind of like how my body can accept, say, 10 grams of vitamin C in a week, but not all in one day?

Or did you mean something else by immunity, as in an actual immune system response?

You're right Jadzia.. I guess my question about immunity is somehow confusing.

I posted this on other thread: I read SB advices everyone to start with the mildest products, then gradually move to stronger products as our skin adjusts to the new skin remodelling process.My question is.. would long term use of SB's products cause the skin to become immune to the products? Meaning that eventually even the strongest formulas would not have any effects on the skin because the skin is adapting so well to the products (from mild to strongest)?

I guess what I'm trying to find out is that, when our skin is at the stage where we can use the strongest SRCP products, does that mean that the milder formula does not work on our skin anymore? Meaning that our skin has built up a tolerance that we actually need a stronger formula? Then, after our skin has adapted well to the strongest formula, it would need an even stronger formula and so on?

It seems that we have three unrelated issues: Hayflick hypothesis, biological homeostatis and immunity, and long-term use of SRCPs.

Perhaps no one answered the questions previously because they require a long response. I'm crazy to answer them, but I've been asked. The Hayflick Limit theory, by the way, is in no way related to the diminishing skin remodeling effect observed in long-term use of SRCPs or any topical actives. Hayflick Limit has to do with a hypothesis on the limits of cell replication. On the other hand, although I have not researched into it, my take on skin acclimating to a topical product or long-term use of a topical active may have something to do with biological and physical homeostatis and not associated with either limited cell life cycle or replication limit or any immunity mediated by antigens and antibodies.

RE: Hayflick Limit Hypothesis

Here is what Dr. Pickart and Skin Biology responded to the questions about Hayflick Limit.

Skin Biology in response to my question on 2/23/2005, http://healthyskin.infopop.cc/eve/forums/a/tpc/f/68...330016713#5330016713

Dr. Pickart, 9/9/2005,
http://healthyskin.infopop.cc/eve/forums/a/tpc/f/68...690000273#6690000273

Dr. Pickart more recently on 2/17/2006,
http://healthyskin.infopop.cc/eve/forums/a/tpc/f/88...930075704#3930075704

And finally Hayflick hypothesis is mentioned at the paragraph subtitled, “Why Aging May be Reversed,” at the web link, “Aging Reversal for Skin and Hair,” http://www.skinbiology.com/renewingskinandhair.html

RE: Biological Homeostatis vs. Immunity

I think our skin’s ability to tolerate new topical actives and later to habituate an old topical active has to do mostly with the mechanism of negative feedback (reverse the direction of change) and to some extend the open feedback (amplify the change in the variable) of homeostatis. Multicellular organisms have the ability or tendency to maintain internal equilibrium by adjusting its physiological processes to maintain stability to survive and in order to live. For example, “Drug addiction is best understood as being due to the modulation of a homeostatis into a positive and negative phase. Any stimulus, drug, or behavior will lose its strength due to learned habituation, but the opponent reaction to the original drug remains strong. In terms of drugs this means that eventually, people who started to take heroin to experience pleasure will be taking it to feel neutral.” Opponent Processes, http://en.wikipedia.org/wiki/Opponent_processes

Just as human body may require increasing dosages of pain medication to control the same physiological pain, for example, skin can adjust to a range of environmental temperature and acidity differences and can similarly become acclimated to topical chemicals such as hydroxy acids of different concentrations at different pH or SRCPs or retinoid acids at different strengths. These types of biological adapbilities to external stimuli most likely do not involve receptor-mediated and “memory” antibodies and white blood cells. This is just my guess.

RE: Long-Term Use of SRCPs (or any topical active)

Biological homeostatis seems a likely explanation why our skin has the tendency to eventually either tolerate or require stronger topical actives, SRCPs or stronger hydroxy acid, to achieve observable progress.

A good way to avoid needing to use increasing high concentrations of topical actives, including SRCPs, is to rest the skin from using a specific active for one or two weeks. Long-term use could be six months to a year. However, three to six months or three to six cycles of twenty-seven days would be my educated guess because 12 weeks often is the minimal required length of time to conduct credible clinical studies on topical actives and since it takes roughly twenty seven days for new skin cells to reach the outermost surface of the epidermis, three or six repeating cycles should be sufficient time for skin remodeling effects and homeostatis to take place.

Another way to determine when it’s time to stop or change your actives would be if you observe that the same SRCPs or hydroxy acid regimen is not producing the same result or the progress has slowed, you could increase or reduce the frequency of the regimen, the concentration of products, or rest from the same actives and use something totally different for a few months.

The length of time required for a rest period will probably depend on the active in question, individual product use, and skin biochemistry in theory; however, as in real-life practice, it probably does not have to be exact. One or two weeks (or to three months) probably would be sufficient.

Similarly, based on the findings of six human clinical studies, CTFA's Cosmetic Ingredient Review (CIR) Expert Panel, the cosmetic industry's independent body for reviewing the safety of cosmetic ingredients, suggests that AHA-induced sensitivity to UV radiation is reversible after discontinuing use of topical glycolic acid after one week. However, the actual time required for reversal of AHA-induced effect with long-term glycolic acid use needs further studies. “Safety Reviews of AHAs,” January 10, 2005, http://www.cfsan.fda.gov/~dms/ahaguid2.html

Long but hopefully satisfactory.

This message has been edited. Last edited by: JW,

thanks JW, I learned some stuff from reading that! And thanks to learnmore for that question.

JW, first, thank you so much for taking the time to write such a long and informative answers. I really appreciate it!!! I'm really amazed that you know so much (also on other threads). I don't know what your background is, but I found that you have provided many informative explanation to other participants on this forum

I just need to confirm my understanding ... does that mean that it will be ok if we use SRCP or any topical drugs "forever", as long as you take some "resting periods" during treatment? In that way, you will not develop any resistant/tolerance/addiction to the drugs/SRCP?

Jadzia, glad to have you on this board

This message has been edited. Last edited by: learnmore,

quote:

Originally posted by learnmore:
Dr. Pickart, thanks for answering my questions. I feel like, the more I read about your articles, the more questions I have.

What about Tri-peptide?

Dear learnmore:

Until Dr. Pickart has a chance to address your question, you may want to review this link on Comparing Peptides Used Commercially

Best Wishes,
-Skin Biology

Hi learnmore,

I appreciate your acknowledgement and praises. Thank you for taking the time to let me know that you find my posts informative. I learned from the questions and experiences of others as well.

With the exception of antibiotic use, I would agree with the general idea of being able to use SRCPs or most topical actives "forever" with some periodic rest periods. My own experiences of using benzoyl peroxide and SRCPs seem to confirm this theoretical idea as well. Treatments of BP or SRCPs seem more effective after a long break.

Dear SB, thanks for your reply. Dr. Pickart please confirm ..

JW, you're most welcome. Hopefully Dr. Pickart can help confirm/clarify our understanding on the "forever with periodic breaks" theory

In the mean time, I can't wait for my SB products to arrive...

This message has been edited. Last edited by: learnmore,

Dear Skin Biology and Dr. Pickart, thank you for the peptide comparison reference link.

I have read what you wrote about the adverse effects and toxicity of various copper peptides, fungal and bacterial peptides, and amino acid complexes. Have you studied the following three regenerative peptides and do they add value or pose problems in a retinol cream?

Palmitoyl Tetrapeptide-3
Palmitoyl Oligopeptide
Hexapeptide-11

Thanks for your input.

I was reading about the different kinds of peptides, and I know that some of them apparently can increase collagen synthesis. I know that, used alone, they do not remove damaged proteins, and reportedly can cause bumpy/knotty skin to develop as a result. However, if used with SRCPs and hydroxy acids, which remove these damaged proteins and suppress TGF-beta-1, could these peptides then be safely used to boost collagen production? What about melatonin? I dont recall the specific names of the peptides, but I think that they were along the same lines as the oligopeptides and hexapeptides. I hope that my question makes sense; my knowledge of these unrelated peptides is quite limited.
Thank you.

You might also use these to boost collagen production but the SRCPs themselves strongly boost collagen.