topical n-acetylcysteine gegen photodamage... [Beitrag #48487] :: Di., 07 November 2006 20:19
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tristan
Beiträge: 709 Registriert: November 2005
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ok, hat jemand ne ahnung welche konzentration nac die genommen haben? jemand den fulltext? seitdem dieses journal über nature.com läuft hat die uni keine freigabe dafür
J Invest Dermatol. 2003 May;120(5):835-41.
Links
Topical N-acetyl cysteine and genistein prevent ultraviolet-light-induced signaling that leads to photoaging in human skin in vivo.
Kang S, Chung JH, Lee JH, Fisher GJ, Wan YS, Duell EA, Voorhees JJ.
Department of Dermatology, University of Michigan, Ann Arbor, Michigan 48109, USA. swkang@umich.edu
Human skin is exposed to solar ultraviolet radiation. Ultraviolet radiation damages human skin and results in an old and wrinkled appearance, called photoaging. We have previously reported that molecular mechanisms by which ultraviolet light causes photoaging involve activation of growth factor and cytokine receptors in keratinocytes and dermal cells. They lead to downstream signal transduction through activation of mitogen-activated protein kinase (extracellular signal-regulated kinase, c-jun N-terminal protein kinase, and p38) pathways. These signaling pathways converge in the nucleus of cells to form an activated complex of transcription factor activator protein 1 (cFos/cJun), which induces matrix metalloproteinases that degrade skin connective tissue. In addition to cell surface receptor activation, generation of reactive oxygen species by ultraviolet radiation is believed to be critical in triggering mitogen-activated protein kinase pathways. We investigated the ability of (i) ultraviolet irradiation to generate reactive oxygen species in human skin in vivo; and (ii) genistein, which possesses both tyrosine kinase inhibitory and antioxidant activities, and n-acetyl cysteine, which can be converted into the endogenous antioxidant glutathione, to impair responses to ultraviolet light that eventuate in photoaging in human skin in vivo. Ultraviolet irradiation caused a rapid and significant increase in hydrogen peroxide levels in human skin in vivo. Pretreatment of human skin with genistein inhibited ultraviolet-induced epidermal growth factor receptor tyrosine kinase activity, whereas n-acetyl cysteine did not. Genistein inhibited ultraviolet induction of both extracellular signal-regulated kinase and cJun N-terminal protein kinase activities. n-Acetyl cysteine inhibited extracellular signal-regulated kinase but not cJun N-terminal protein kinase activation. Both genistein and n-acetyl cysteine prevented ultraviolet induction of cJun protein. Consistent with this, genistein and n-acetyl cysteine blocked ultraviolet induction of cJun-driven enzyme, collagenase. Neither genistein nor n-acetyl cysteine acted as sunscreens as they had no effect on ultraviolet-induced erythema. These data indicate that compounds similar to genistein and n-acetyl cysteine, which possess tyrosine kinase inhibitory and/or antioxidant activities, may prevent photoaging.
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Re: topical n-acetylcysteine gegen photodamage... [Beitrag #48553 ist eine Antwort auf Beitrag #48546] :: Di., 07 November 2006 21:46
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pilos
Beiträge: 26887 Registriert: November 2005 Ort: Ausland
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tristan schrieb am Die, 07 November 2006 21:33 |
cool, danke. hatte eben auch noch was gelesen da wurde bei babys 10% für sicher gehalten.
gibt es glaub ich auch als pulver.. weißt du ob es in Ungt Basalis Dac Basissalbe löslich ist? Na, wird der Apotheker wissen, aber deine Meinung ist trotzdem appreciated..
LG
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ich würde vorher das NAC in die kleinste menge aqua dest. in die sich so grade löst, auflösen und dann mit der Basissalbe portionsweise verühren...
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Re: mal noch allgemein [Beitrag #48745 ist eine Antwort auf Beitrag #48738] :: Mi., 08 November 2006 22:12
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pilos
Beiträge: 26887 Registriert: November 2005 Ort: Ausland
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Figaro03 schrieb am Mit, 08 November 2006 22:04 | Kann man den Effekt eigentlich nicht auch dann erzielen, wenn man NAC oral einnimmt?
Der Stoff müsste doch dann auch in die Zellen verteilt werden?
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nein.....dann musst du um die gleiche konzentration zu erreichen...so 100-200 gram NAC am tag schlucken....
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Re: topical n-acetylcysteine gegen photodamage... [Beitrag #48763 ist eine Antwort auf Beitrag #48737] :: Do., 09 November 2006 01:54
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tristan
Beiträge: 709 Registriert: November 2005
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Figaro03 schrieb am Mit, 08 November 2006 22:02 | tristan, für was willst das benutzen?
schon klar für Sonne, allerdings hast du doch ne ziemlich starke Sonnenmilch. entstehen dann überhaupt noch Uv-Schäden, wenn so gut wie keine Strahlen mehr durchkommen?
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deswegen:
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"In vehicle-treated normal skin, glutathione exists predominantly (83%) in its reduced form (GSH) with a small percentage (17%) in its oxidized form (GS-SG). Following 8 h of topical treatment, NAC completely eliminated the oxidized form of glutathione in human skin, whereas the reduced form was increased by 20% (p<0.05) (Figure 4). The GSH level peaked at 24 h, but continued to stay significantly elevated 48 h after topical application of NAC. By this time, GS-SG could be detected again, although still significantly less than in vehicle-treated skin. Thus, topical NAC leads to a significant increase in the endogenous antioxidant pool of reduced glutathione (the form that can scavenge ROS) in human skin in vivo.
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Genistein and NAC inhibit the UV induction of collagenase mRNA
As cJun induction is necessary for AP-1 activation, genistein and NAC would be expected to inhibit UV induction of AP-1 dependent genes, such as MMP-1. Indeed, both genistein and NAC pretreatments markedly inhibited the UV induction of MMP-1 mRNA (Figure 8a,b). We have previously demonstrated that UV-enhanced MMP-1 mRNA expression is localized in epidermal cells as well as in dermal fibroblasts
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AP-1 activity is required for induction of several members of the MMP family, which have been implicated as key mediators of photoaging in humans
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The fact that blockade of ERK by NAC resulted in cJun inhibition in human skin in vivo supports a critical role for ERK in cJun induction and underscores the complicated network involved in intracellular signaling in mammalian cells. Consistent with their ability to inhibit cJun induction by UV, NAC and genistein blocked AP-1 regulated MMP-1 expression. As UV-induced MMPs are key molecular mediators of photoaging by degradation of the dermal matrix, the ability of genistein and NAC to significantly block MMP induction suggests their potential to prevent photoaging. We have previously shown that pretreatment with all-trans retinoic acid (RA) also blocks UV-induced cJun protein and AP-1, thereby blocking MMP expression and consequent collagen degradation in human skin
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die Mechanismen sind nicht auf UV beschränkt..
Jegliche Hautirritation wird dadurch wahrscheinlich gedämpft.
und selbst der intrinsischen Hautalterung dürfte es entgegenwirken, bei retinoic acid z.b. hat man letztens auch gezeigt dass es dabei wirkt, nicht nur bei UV Schaden. Da RA aber auch starke Nebenwirkungen/bzw. für mich schlechte Wirkungen hat ist das ne gute Alternative. Im Volltext habe ich auch das Gefühl bekommen dass die glauben es wirkt sogar besser als Retinoic acid weil NAC weiter oben in der Kette eingreift als RA. Siehe auch das Bild aus dem Thermal Aging Text (anderer Thread bzgl. Sauna)..
http://www.alopezie.de/fud/index.php/fa/1979/4faac4bf5043867 8bc3c1ba9c1f00e22/
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