JOURNAL OF COSMETIC SCIENCE 112 In a same manner, sebum production was evaluated with the Sebumeter® technology. With this photometric device, the total mass of lipids excreted by surface unit (in μg/cm²) can be quantifi ed by refl ectometry (Figure 5). At D15, there was a signifi cant (p 0.0001) decrease in sebum production on treated scalp by -58% compared to baseline (D0). The decrease in sebum production was continuous until the end of the study to reach a fi nal -67% (p 0.0001) compared to baseline (D0). Visual improvement of the scalp, both for quantity of fl akes and sebum production, was clearly noticeable, as shown by macrophotography (Figure 6). Photos of scalp taken at D0 D3 and D30 on volunteer 20 displayed less adherent fl akes on hair and scalp, and less greasy appearance at the end of the study (D30) before treatment (D0). CONCLUSION The study reported here identifi es E. angustifolium extract as an effi cient antidandruff and antisebum cosmetic active ingredient targeting the three main characteristics of the skin disorder (sebum production, SC disruption, and skin infl ammation). We propose that one important molecular mechanism underlying E. angustifolium extract effi cacy involves nor- malization of defensins (hBD2 and hBD3) and TLR2 expression to limit infl ammatory skin response to Malassezia infection. To our knowledge, this is the fi rst time that an antidandruff active is associated with immunomodulation of the skin response to Malas- sezia invasion. REFERENCES (1) C. Pierard-Franchimont, E. Xhaufl aire-Uhoda, and G. E. Pierard, Revisiting dandruff, Int. J. Cosmet. Sci., 28(5), 311–318 (2006). (2) J. R. Schwartz, A. G. Messenger , A. Tosti, G. Todd, M. Hordinsky, R. J. Hay, X. Wang, C. Zachariae, K. M. Kerr, J. P. Henry, R. C. Rust, and M. K. Robinson, A comprehensive pathophysiology of dandruff and seborrheic dermatitis - towards a more precise defi nition of scalp health, Acta. Derm. Venereol., 93(2), 131–137 (2013). (3) J. R. Schwartz, C. M. Cardin, and T. L. Dawson Jr., “Dandruff and Seborrheic Dermatitis,” in Textbook of Cosmetic Dermatology, 3rd Ed., R. Baran and H. I. Maibach. Eds. (CRC Press, London, New York, 2004), pp. 259–272. Figure 6. Epilobium angustifolium extract improves scalp appearance.

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