Hai ragione ad essere perplesso Fabrizio, il lavoro sulla vacuolizzazione da deanolo (DMAE) è poco significativo.
E' stato fatto nel 2007, e ogni tanto gira l'allarme.
Segue un po' di materiale, da pubmed
Morissette G, Germain L, Marceau F.
Centre de Recherche en Rhumatologie et Immunologie, Centre Hospitalier Universitaire de Québec, Québec QC, Canada.
BACKGROUND: The 'cosmeceutical' agent 2-dimethylaminoethanol (DMAE) is a tertiary amine found in high concentration in numerous topical antiwrinkle preparations. OBJECTIVES: We hypothesized that a 337 mmol L(-1) (3%) DMAE reservoir applied to the skin could reproduce the cytopathology induced by other amines by maintaining a millimolar drug concentration within a certain depth of the skin layers, and that vacuolar cell expansion could account for the very rapid effect on the apparent skin fullness. METHODS: Morphological and functional assays were applied to cultured rabbit dermal fibroblasts treated with tertiary amines in vitro. A morphological verification of the vacuolization caused by topical DMAE was also attempted in vivo using the inner skin of the rabbit ear and in vitro using primary cultures of human cutaneous epithelial cells. RESULTS: Fibroblasts responded to DMAE (2.5-10 mmol L(-1)) by massive vacuolization (0.5-4 h; phase contrast observations). Triethanolamine, another chemical frequently used topically, was also active in this respect (10 mmol L(-1)). The vacuolar adenosine triphosphatase inhibitor bafilomycin A1 prevented DMAE- or triethanolamine-induced vacuolization; adding bafilomycin A1 or cell washout slowly reversed the established vacuolization induced by DMAE. Further effects of DMAE in cultured fibroblasts included a moderate cytotoxicity (10 mmol L(-1)) that was abated by bafilomycin A1 cotreatment, a concentration-dependent mitotic arrest (2.5 mmol L(-1)) and transient and mild effects on cell ploidy. The epidermis of the rabbit external ear was significantly thickened and exhibited clear perinuclear swelling indicative of vacuolization in response to 3% DMAE (1 h; paraffin tissue sections). Cultured human cutaneous epithelial cells responded to DMAE by vacuolization (inhibited by bafilomycin A1 cotreatment). CONCLUSIONS: The vacuolar cytopathology induced by concentrated organic amines may be the cellular basis of the antiwrinkle effect of DMAE.
Nota di Riky: a te, Fab, questo sembra un lavoro ben condotto???
Questo che segue invece è del 2005:
The role of dimethylaminoethanol in cosmetic dermatology.
Skincare formulations for the improvement of aging skin are increasingly important consumer products. Here, we review available data on one such agent - 2-dimethylaminoethanol (DMAE) or deanol - that has recently been evaluated in a placebo-controlled trial. DMAE is an analog of the B vitamin choline and is a precursor of acetylcholine. Although the role of acetylcholine as a neurotransmitter is well known, growing evidence points to acetylcholine as a ubiquitous cytokine-like molecule that regulates basic cellular processes such as proliferation, differentiation, locomotion, and secretion in a paracrine and autocrine fashion. Indeed, this modulatory role may contribute to the cutaneous activity of DMAE.In a randomized clinical study, 3% DMAE facial gel applied daily for 16 weeks has been shown to be safe and efficacious (p < 0.05) in the mitigation of forehead lines and periorbital fine wrinkles, and in improving lip shape and fullness and the overall appearance of aging skin. These effects did not regress during a 2-week cessation of application. Beneficial trends (p > 0.05 but </= 0.1) were noted in the appearance of coarse wrinkles, under-eye dark circles, nasolabial folds, sagging neck skin, and neck firmness. Application was found to be well tolerated, with no differences in the incidence of erythema, peeling, dryness, itching, burning, or stinging between the DMAE and placebo groups. An open-label extension of the trial showed that the long-term application of DMAE gel for up to 1 year was associated with a good safety profile. The acute skin-firming effects of DMAE have been confirmed by quantitative measures of cutaneous tensile strength. In vitro studies in peripheral blood lymphocytes indicate that DMAE is a moderately active anti-inflammatory agent. Although its mechanisms of action in the skin remain to be elucidated, evidence suggests that the skin is an active site of acetylcholine synthesis, storage, secretion, metabolism, and receptivity. Muscarinic acetylcholine receptors have been localized to keratinocytes, melanocytes and dermal fibroblasts, whereas nicotinic acetylcholine receptors have been found in keratinocytes. The role of acetylcholine and the role of DMAE as a modulator of acetylcholine-mediated functions in the skin remain to be elucidated.Thus, the benefits of DMAE in dermatology include a potential anti-inflammatory effect and a documented increase in skin firmness with possible improvement in underlying facial muscle tone. Studies are needed to evaluate the relative efficacy of DMAE compared with other skin-care regimens (e.g., topical antioxidant creams, alpha-hydroxy acids).
PMID: 15675889 [PubMed - indexed for MEDLINE]