Ageing processes influence keratin and KAP expression in human hair follicles.

In many cultures, a youthful look is strictly linked to strong and healthy hair. Source of the hair fibre is the hair follicle, a highly specialized skin appendage. Biological alterations because of intrinsic or extrinsic stimuli can destabilize this perfectly organized system, thus effecting hair growth or metabolism. Also, ageing could be characterized as a disturbance in this well-balanced machinery. Albeit the predominant symptom of hair ageing, greying, is addressed in a plurality of research activities, further age-related changes, e.g. related to hair structure, remain obscure. Therefore, we characterized hair follicles of two volunteer panels (below 25 years, above 50 years) on the molecular level, especially focussing on alterations influencing gene expression of keratins and keratin-associated proteins. We showed that concordantly to other biological systems the hair follicle undergoes several modifications during the ageing process associated among others with a significant decline in these structural proteins. Providing strategies to fight against these age-related changes is a challenge for hair science.

Hydrolysed wool: a novel chelating agent for metal chelant-assisted phytoextraction from soil.

Phytoextraction has revealed great potential, however it is limited by the fact that plants need time and nutrient supply and have a limited metal uptake capacity. Although the use of synthetic chelators, such as EDTA, enhances heavy metal extraction, it also produces the negative side effects of high phytotoxicity, as well as leaching of essential metals. The aim of this research was to investigate the application of wool, in mobilising metals and in improving the phytoextraction of metals-contaminated soil. We performed column experiments with 14 d and 7 d partially hydrolysed wool as chelating agent on a silty-loamy sand agricultural soil. In the column experiment the 14 d wool hydrolysate mobilised 68% of Cu in soil, whereas in the case of Cd it mobilised 5.5%. The model plant selected for the phytoextraction experiments was tobacco (Nicotiana tabacum). The plant uptake of Cd and Cu, assisted by the application of 6.6 g kg(-1) wool hydrolysate was increased by 30% in comparison to the control plants. The application of 13.3 g kg(-1) wool hydrolysate enhanced the Cu uptake by up to 850%. Moreover, high leaching probability frequently observed when applying chelating agents, such as EDTA or ethylene diamine disuccinate (EDDS), were not detected. The use of hydrolysed wool therefore merits further investigation.