Procyanidin Oligomers Selectively and Intensively Promote Proliferation of Mouse Hair Epithelial Cells In Vitro and Activate Hair Follicle Growth In Vivo11The authors disclosed conflict of interest.

Abstract

We have previously reported that proanthocyanidins extracted from grape seeds possess growth-promoting activity toward murine hair epithelial cells in vitro and stimulate anagen induction in hair cycle progression in vivo. This report constitutes a comparison of the growth-promoting activity of procyanidin oligomers and the target cells of procyanidins in the skin. Results show that procyanidin dimer and trimer exhibit higher growth-promoting activity than the monomer. The maximum growth-promoting activity for hair epithelial cells with procyanidin B-2, an epicatechin dimer, reached about 300% (30 microM) relative to controls (= 100%) in a 5 d culture. Optimum concentration of procyanidin C-1, an epicatechin trimer, was lower than that of procyanidin B-2; the maximum growth-promoting activity of procyanidin C-1 was about 220% (3 microM). No other flavonoid compounds examined exhibit higher proliferative activities than the procyanidins. In skin constituent cells, only epithelial cells such as hair keratinocytes or epidermal keratinocytes respond to procyanidin oligomers. Topical application of 1% procyanidin oligomers on shaven C3H mice in the telogen phase led to significant hair regeneration [procyanidin B-2, 69.6% +/- 21.8% (mean +/- SD); procyanidin B-3, 80.9% +/- 13.0%; procyanidin C-1, 78.3% +/- 7.6%] on the basis of the shaven area; application of vehicle only led to regeneration of 41.7% (SD = 16.3%). In this paper, we demonstrate the hair-growing activity of procyanidin oligomers both in vitro and in vivo, and their potential for use as agents to induce hair growth.

Influence of Cocoa Flavanols and Procyanidins on Free Radical‐induced Human Erythrocyte Hemolysis

“…Previous studies reported that procyanidins have a stronger protective effect than their monomeric units in vitro (Lotito et al 2000, Arteel et al 1999, Takahashi et al 1999, Zhu et al 2002. This is different from the present result in which epicatechin demonstrated stronger protection than Dimer B2.…”

Inhibitory effects of grape procyanidins on free radical-induced cell damage in rat hepatocytesin vitro

“…Furthermore, in terms of the effect of GPC on normal cell proliferation, cells treated with different doses of GPC had higher proliferative activities than the normal control, and an obvious dose-dependent response was obtained: the higher dose of GPC the cells received, the better cell proliferative activity observed. This indicated that GPC promoted cell proliferation in normal hepatocytes and our data is similar to the previous reports on GPC stimulating hair cell growth [10,11] . The stimulating effect of GPC in normal cell proliferation might be associated with its inhibitory effect on endogenous free radicals-generated cell injury, and the precise mechanism needs further investigations.…”

Aqueous Extract of Peanut Skin and Its Main Constituent Procyanidin A1 Suppress Serum IgE and IgG1 Levels in Mice-Immunized with Ovalbumin

“…1), respectively. [12][13][14]17,23) We therefore tried to compare the effects of GP and AP with the effects of PSE on IgE and IgG1 levels in mice-immunized with OVA. Orally administered AP at a dose of 30 mg/kg/d significantly reduced IgE levels, whereas AP and GP did not reduce total IgG1 levels at the same dose (Figs.…”