Citazione:Messaggio inserito da Marlin
Nel frattempo non solo Shiseido, ma anche altre ditte minori avevano offerto a prezzi più abbordabili questo estratto e quindi un certo numero non esiguo di persone l'ha provato e lo sta provando essendo ancora in vendita.
Sì, chiederò numi a Marliani, ma lentamente, altrimenti verrebbe subissato dalle mie mail e probabilmente non risponderebbe più. Ti allego alcuni studi intesi a indagare i messaggi biochimici autocrini e paracrini che modulano la vita dei capelli - uno di questi è stato promosso dalla Shiseido, l'altro da team di ricercatori giapponesi, sempre all'avanguardia.
Citazione:Role of TGF-beta2 in the human hair cycle.
Hibino T, Nishiyama T.
Shiseido Life Science Research Center, 2-12-1 Fukuura, Kanazawa-ku, Yokohama 236-8643, Japan. toshihiko.hibino@to.shiseido.co.jp
Male pattern baldness is the result of premature entry into catagen due to androgens. In order to prevent hair loss, it is important to understand two critical steps, i.e., the induction mechanism of premature entry and the regression process of catagen. At the initiation, dihydrotestosterone (DHT) stimulates synthesis of transforming growth factor-beta2 (TGF-beta2) in dermal papilla cells. TGF-beta2 suppresses proliferation of epithelial cells and stimulates synthesis of certain caspases. Then TGF-beta2 triggers the intrinsic caspase network and subsequently epithelial cells are eliminated through apoptotic cell death. TGF-beta antagonists are effective in preventing catagen-like morphological changes and in promoting elongation of hair follicles in vivo and in vitro. These lines of evidence strongly suggest the presence of a catagen cascade in male pattern baldness, involving: (1) the conversion of testosterone to DHT by type II 5-alpha-reductase; (2) the synthesis of TGF-beta2 in dermal papilla cells; and (3) the activation of the intrinsic caspase network. These sequential events contribute to the shortening of the human hair cycle. Copyright 2004 Japanese Society for Investigative Dermatology
Citazione: Br J Dermatol. 2005 Apr;152(4):623-31. Related Articles, Links
Interferon-gamma is a potent inducer of catagen-like changes in cultured human anagen hair follicles.
Ito T, Ito N, Saathoff M, Bettermann A, Takigawa M, Paus R.
Department of Dermatology, University Hospital Hamburg-Eppendorf, University of Hamburg, Martinistr. 52, D-20246 Hamburg, Germany.
BACKGROUND: Interferon (IFN)-gamma appears to be an important hair cycle modulator in mice. It is unclear whether it has similar hair growth modulatory functions in human hair follicles. OBJECTIVES: To study whether IFN-gamma can be exploited to modulate the growth, pigmentation and/or cycling of organ-cultured human anagen scalp hair follicles, as an in vitro indicator system for how IFN-gamma affects human hair growth in vivo. This was correlated with the hair follicle expression patterns of IFN-gamma receptors alpha and beta. In addition, we wanted to establish a new, simple tool for the rapid experimental induction of catagen in vitro. METHODS: Normal human scalp hair follicles in the anagen VI stage of the hair cycle were cultured according to the method of Philpott et al., with or without IFN-gamma (50-1000 IU mL(-1)). Hair shaft elongation and pigmentation changes were measured, complemented by quantitative histomorphometry to assess changes in hair follicle cycling (hair cycle score), proliferation (Ki-67), melanogenesis (Masson-Fontana) and apoptosis (TUNEL). IFN-gamma receptors were also localized by immunofluorescence and EnVision technique. As transforming growth factor (TGF)-beta2 is a recognized key inducer of catagen in human hair follicles, TGF-beta2 expression was investigated by tyramide signal amplification and reverse transcription-polymerase chain reaction in anagen hair follicles treated with vehicle (phosphate-buffered saline) or IFN-gamma. RESULTS: IFN-gamma rapidly inhibited hair elongation in cultured human anagen hair follicles and induced morphological signs of catagen transformation after only 4 days of culture, i.e. faster than with other reported catagen-inducers (e.g. TGF-beta2). Proliferation was inhibited, apoptosis was increased and follicular melanogenesis was switched off in hair bulb keratinocytes treated in situ with IFN-gamma. Anagen hair follicles displayed strong IFN-gamma receptor alpha-like immunoreactivity, while the immunoreactivity for IFN-gamma receptor beta in the hair matrix was only weak. TGF-beta2 immunoreactivity and mRNA transcript levels were enhanced in hair follicles treated with IFN-gamma. CONCLUSIONS: These data suggest that IFN-gamma is a potent catagen inducer in normal human scalp hair follicles, which express cognate receptors, and show that IFN-gamma administration offers an excellent tool for experimental catagen induction in organ-cultured human hair follicles. This catagen induction probably occurs at least in part via upregulation of the recognized catagen-stimulatory growth factor TGF-beta2.
Citazione:Io credo che esteticamente siano validi quelle sostanze che agiscono sull'ispessimento, mentre quelle che agiscono sull'allungamento non cambiano nulla. E' importante però capire quali fattori agiscono in un senso e quali nell'altro. Dai risultati dei test l'Adenosil sembrerebbe in questo senso anche migliore del minox portando a una crescita media dello spessore del fusto del 55% in otto mesi (non è il raddoppio che sarebbe il 100% e che vorrebbe dire raddoppiare la copertura, ossia come raddoppiare i capelli, ma poco più della metà dello stesso). Sarà però tutto vero ?
Dunque Marliani mi ha detto che francamente non vede l'utilità di una lozione così composta di lasciar perdere ma, ha soggiunto, quasi a precisare che è fallibile come tutti i mortali, se son rose... Personalmente credo che aspetterò le valutazioni dei primi pionieri...
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