The green autofluorescence intensity and asymmetry of older men is significantly higher than those of older women in their fingernails and certain regions of skin

Our recent studies have suggested that the patients of multiple diseases have characteristic Pattern of Autofluorescence (AF) in their skin and fingernails, which may become novel biomarkers for both disease diagnosis and evaluation of health state. Since male populations may have higher levels of oxidative stress and inflammation than female population, in our current study we tested our hypothesis that the green AF intensity of older men is higher than that of older women in their fingernails and skin. We found that in both left and right Index Fingernails, the green AF intensity of the men of both the age group of 61 - 70 years of old and the age group of 71 - 80 years of old is significantly higher than that of the women of the same age groups. At both left Dorsal Centremetacarpus and left Centremetacarpus, the green AF intensity of the men at the age between 71 - 80 years of old is also significantly higher than that of the women of the same age group. Moreover, in Index Fingernails, Dorsal Centremetacarpus and Centremetacarpus, the green AF asymmetry of the older men of certain age groups is significantly higher than that of the women of the same age groups. Collectively, our study has provided the first evidence indicating the gender difference between the green AF intensity and asymmetry of older men and those of older women in their fingernails and certain regions of skin, which is valuable for establishing the AF-based diagnostic method.