HAIR AND HYDROLYZED WHEAT PROTEINS 201 .! Figure 5. Bleached hair treated overnight with fluorescein-labeled peptides. Physical section. Note the lower intensity of fluorescence at the hair's periphery as compared with the untreated hairs shown in Figures 2 and 3. . .... '.. Figure 6. Ethnic black hair after relaxer (no. 6), treated for 30 minutes with fluorescein-labeled peptides. Physical section. In this micrograph at high-magnification intensely stained nuclear remnants are again evident. The boundaries of the cortical cells are clearly defined at a lesser intensity, and a fine network of weakly stained non-keratin material is just visible within each cell.
202 JOURNAL OF COSMETIC SCIENCE Figure 7. A split end treated for 30 minutes with fluorescein-labeled peptides. Block top method. The hair has split into many separated fragments. Intense staining of the cortical nuclear remnants is still visible but not as sharp as in less damaged hairs. The continuous low level of fluorescence indicates that the peptides have permeated throughout the entire specimen. pervaded all parts, but it was noticeable that the nuclear remnants were not as sharply defined as had been seen in untreated hairs and of much lower intensity. The most likely reason for this is that effete basic nuclear proteins, normally found in untreated hairs, had been extracted during the multifarious processes of weathering. IMPLICATIONS FOR TOILETRY TREATMENTS OF HAIR Since water normally plasticizes and softens hair, the results of Gamez-Garcia (1) and Chahal et al. (2) provide expectations for significant changes in the textural behavior of human hair following treatment with hydrolyzed wheat proteins. The relatively un- crosslinked proteins of the hair's intermacrofibrillar matrix are major sites for binding water (9) and can be regarded as the main plasticizing elements separating the stiffer macrofibrils in undamaged root-end hair. Exposure of hair to excessive sunlight dra- matically increases its susceptibility to splitting (10), likely through the formation of new crosslinks in the intermacrofibrillar matrix but also through a loss of water-binding capacity. The absorption of hydrolyzed wheat proteins will increase the plasticity of hair in general by dint of their ability to retain moisture for long periods. We predict that their specific incorporation into the very components that are damaged by sunlight exposure will render the hair less susceptible to the formation of split ends. ACKNOWLEDGMENTS Particular thanks are due to Dr. Vyvyan Howard of the Department of Infant and Fetal Toxico-Pathology of Liverpool University for providing access to his confocal microscope and to Mr. Liam Barlow of the same department for technical assistance with the work.
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200 JOURNAL OF COSMETIC SCIENCE Figure 4. Permanently waved hair treated overnight with fluorescein-labeled peptides. Physical section. This high-magnification micrograph shows that the components containing the fluorescer are the endocu- ticle (EN), and nuclear remnants (NR), the intermacrofibrillar matrix (IM), and cell boundaries (CB) of the cortex. wheat proteins and basic proteins, notably effete nuclear proteins (histones), expected to be present within these structures (6). In most, but not all, hairs that had undergone chemical processing (bleaching, perma- nent waving, and relaxer treatments), a peripheral annulus was seen extending to a depth of approximately 15 pro, where fluorescence was at a lower intensity than at greater depths in the fibers (cf. Figure 5). In these regions the nuclear remnants were poorly defined. Such effects could have been caused in the water-rinsing step by easier removal of the wheat peptides from chemically treated hairs than from untreated hairs. Another possibility is that basic proteins, to which the wheat peptides normally attach, have been removed from the hairs during the chemical treatments. In the case of the bleached hairs, cysteic acid formed in the peripheral annulus could have shifted the isoionic point of the local proteins to a lower pH, thereby opposing ionic binding of the wheat peptides. In ethnic black hairs, subjected beforehand to relaxer treatments, there was some evi- dence that the cortical cells contained a network of stained intermacrofibrillar matrix that was more extensive than seen in the other hairs of Caucasian origin (compare Figures 4 and 6). This would be consistent with earlier electron microscope observations that the highly crimped hairs of ethnic blacks contain more cells of an ortho-cortical character than are found in the straighter hairs of other racial groups (7,8). More work of a quantitative nature would be required to reach a firm conclusion about this. In some cases transverse sections through a split end indicated a simple bifurcation involving fracture through the hair's major axial diameter, and in others as many as 18 separated fibrillar units were seen (cf. Figure 7). The fluorescently labeled peptides had
HAIR AND HYDROLYZED WHEAT PROTEINS 201 .! Figure 5. Bleached hair treated overnight with fluorescein-labeled peptides. Physical section. Note the lower intensity of fluorescence at the hair's periphery as compared with the untreated hairs shown in Figures 2 and 3. . .... '.. Figure 6. Ethnic black hair after relaxer (no. 6), treated for 30 minutes with fluorescein-labeled peptides. Physical section. In this micrograph at high-magnification intensely stained nuclear remnants are again evident. The boundaries of the cortical cells are clearly defined at a lesser intensity, and a fine network of weakly stained non-keratin material is just visible within each cell.

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