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Effect of shampoo, conditioner and permanent waving on the molecular structure of human hair.

Zhang Y, Alsop RJ, Soomro A, Yang FC, Rheinstädter MC - PeerJ (2015)

Bottom Line: We found that a single use of shampoo and conditioner has no effect on packing of keratin molecules, structure of the intermediate filaments or internal lipid composition of the membrane complex.Single application of a perming product was found to deeply penetrate the hair and reduce the number of keratin coiled-coils and change the structure of the intermediate filaments.Signals related to the coiled-coil structure of the α-keratin molecules at 5 and 9.5 Å were found to be decreased while a signal associated with the organization of the intermediate filaments at 47 Å was significantly elevated in permed hair.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Physics & Astronomy, McMaster University , Hamilton, ON , Canada.

ABSTRACT
The hair is a filamentous biomaterial consisting of the cuticle, the cortex and the medulla, all held together by the cell membrane complex. The cortex mostly consists of helical keratin proteins that spiral together to form coiled-coil dimers, intermediate filaments, micro-fibrils and macro-fibrils. We used X-ray diffraction to study hair structure on the molecular level, at length scales between ∼3-90 Å, in hopes of developing a diagnostic method for diseases affecting hair structure allowing for fast and noninvasive screening. However, such an approach can only be successful if common hair treatments do not affect molecular hair structure. We found that a single use of shampoo and conditioner has no effect on packing of keratin molecules, structure of the intermediate filaments or internal lipid composition of the membrane complex. Permanent waving treatments are known to break and reform disulfide linkages in the hair. Single application of a perming product was found to deeply penetrate the hair and reduce the number of keratin coiled-coils and change the structure of the intermediate filaments. Signals related to the coiled-coil structure of the α-keratin molecules at 5 and 9.5 Å were found to be decreased while a signal associated with the organization of the intermediate filaments at 47 Å was significantly elevated in permed hair. Both these observations are related to breaking of the bonds between two coiled-coil keratin dimers.

No MeSH data available.


Related in: MedlinePlus

Wide angle X-ray scattering (WAXS).(A) The wide angle X-ray diffraction data for the qz direction. There is a noticeable decrease of the 5.0 Å signal corresponding to α-keratin helix distances in comparison with the lipid signal at 4.3 Å. (B) The wide angle X-ray diffraction data for the q‖ direction. There is a noticeable decrease of the 9.8 Å signal corresponding to α-keratin helix distances in comparison with the lipid signal at 4.3 Å.
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fig-6: Wide angle X-ray scattering (WAXS).(A) The wide angle X-ray diffraction data for the qz direction. There is a noticeable decrease of the 5.0 Å signal corresponding to α-keratin helix distances in comparison with the lipid signal at 4.3 Å. (B) The wide angle X-ray diffraction data for the q‖ direction. There is a noticeable decrease of the 9.8 Å signal corresponding to α-keratin helix distances in comparison with the lipid signal at 4.3 Å.

Mentions: Another change is observed after integrating the WAXD data along both the q‖ and qz directions. In the q‖-direction, the peak at 9.5 Å is noticeably decreased in comparison to the 4.3 Å peak after perming. In the qz-direction, the peak at 5.0 Å is also decreased in comparison to the peak at 4.3 Å. This change is visualized in Fig. 6. Both of these peaks refer to the coiled-coil protein structure, i.e., the α-helical keratin packing distances, while the peak at 4.3 Å refers to lipid packing. The peak at 2.08 Å−1 or ∼3 Å is the result of instrumental background and has no relation to hair structure.


Effect of shampoo, conditioner and permanent waving on the molecular structure of human hair.

Zhang Y, Alsop RJ, Soomro A, Yang FC, Rheinstädter MC - PeerJ (2015)

Wide angle X-ray scattering (WAXS).(A) The wide angle X-ray diffraction data for the qz direction. There is a noticeable decrease of the 5.0 Å signal corresponding to α-keratin helix distances in comparison with the lipid signal at 4.3 Å. (B) The wide angle X-ray diffraction data for the q‖ direction. There is a noticeable decrease of the 9.8 Å signal corresponding to α-keratin helix distances in comparison with the lipid signal at 4.3 Å.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4636411&req=5

fig-6: Wide angle X-ray scattering (WAXS).(A) The wide angle X-ray diffraction data for the qz direction. There is a noticeable decrease of the 5.0 Å signal corresponding to α-keratin helix distances in comparison with the lipid signal at 4.3 Å. (B) The wide angle X-ray diffraction data for the q‖ direction. There is a noticeable decrease of the 9.8 Å signal corresponding to α-keratin helix distances in comparison with the lipid signal at 4.3 Å.
Mentions: Another change is observed after integrating the WAXD data along both the q‖ and qz directions. In the q‖-direction, the peak at 9.5 Å is noticeably decreased in comparison to the 4.3 Å peak after perming. In the qz-direction, the peak at 5.0 Å is also decreased in comparison to the peak at 4.3 Å. This change is visualized in Fig. 6. Both of these peaks refer to the coiled-coil protein structure, i.e., the α-helical keratin packing distances, while the peak at 4.3 Å refers to lipid packing. The peak at 2.08 Å−1 or ∼3 Å is the result of instrumental background and has no relation to hair structure.

Bottom Line: We found that a single use of shampoo and conditioner has no effect on packing of keratin molecules, structure of the intermediate filaments or internal lipid composition of the membrane complex.Single application of a perming product was found to deeply penetrate the hair and reduce the number of keratin coiled-coils and change the structure of the intermediate filaments.Signals related to the coiled-coil structure of the α-keratin molecules at 5 and 9.5 Å were found to be decreased while a signal associated with the organization of the intermediate filaments at 47 Å was significantly elevated in permed hair.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Physics & Astronomy, McMaster University , Hamilton, ON , Canada.

ABSTRACT
The hair is a filamentous biomaterial consisting of the cuticle, the cortex and the medulla, all held together by the cell membrane complex. The cortex mostly consists of helical keratin proteins that spiral together to form coiled-coil dimers, intermediate filaments, micro-fibrils and macro-fibrils. We used X-ray diffraction to study hair structure on the molecular level, at length scales between ∼3-90 Å, in hopes of developing a diagnostic method for diseases affecting hair structure allowing for fast and noninvasive screening. However, such an approach can only be successful if common hair treatments do not affect molecular hair structure. We found that a single use of shampoo and conditioner has no effect on packing of keratin molecules, structure of the intermediate filaments or internal lipid composition of the membrane complex. Permanent waving treatments are known to break and reform disulfide linkages in the hair. Single application of a perming product was found to deeply penetrate the hair and reduce the number of keratin coiled-coils and change the structure of the intermediate filaments. Signals related to the coiled-coil structure of the α-keratin molecules at 5 and 9.5 Å were found to be decreased while a signal associated with the organization of the intermediate filaments at 47 Å was significantly elevated in permed hair. Both these observations are related to breaking of the bonds between two coiled-coil keratin dimers.

No MeSH data available.


Related in: MedlinePlus