Correlation analysis between advanced glycation end products detected noninvasively and skin aging factors.

OBJECTIVE: To investigate the correlation between advanced glycation end products (AGEs) and skin elasticity or blood perfusion values in healthy people of different age groups and to evaluate the relationship between noninvasive detection of AGEs and age or skin aging. METHODS: One hundred and two healthy people were enrolled and grouped into groups of 20 years old. Group I: 19-40 years old; Group II: 41-60 years old; Group III: 61-80 years old. Noninvasive techniques such as fluorescence spectroscopy and laser speckle flowmetry were used to detect AGEs levels, local skin perfusion value, and skin elasticity in skin tissue at all age groups. RESULT: The AGEs in the skin increased with age, and the difference between the three age groups was statistically significant (P < .05).There was no significant difference in gender between AGEs (P > .05).There was no significant relationship between AGEs and skin elasticity or blood perfusion value in the Group I; there was a low correlation between AGEs and skin elasticity in the 41-60 years age group (r < .4, P < .05). The level of AGEs in the elderly over 60 years was significantly positively correlated with skin elasticity and blooding perfusion value (r > .4, P < .05). CONCLUSION: There is a significant correlation between AGEs and age or skin aging indicators. As the age increasing, the level of AGEs increases obviously, which can be used as a potential noninvasive tool for detecting skin aging.

Quantitative proteomics analysis of young and elderly skin with DIA mass spectrometry reveals new skin aging-related proteins.

Skin aging is a specific manifestation of the physiological aging process that occurs in virtually all organisms. In this study, we used data independent acquisition mass spectrometry to perform a comparative analysis of protein expression in volar forearm skin samples from of 20 healthy young and elderly Chinese individuals. Our quantitative proteomic analysis identified a total of 95 differentially expressed proteins (DEPs) in aged skin compared to young skin. Enrichment analyses of these DEPs (57 upregulated and 38 downregulated proteins) based on the GO, KEGG, and KOG databases revealed functional clusters associated with immunity and inflammation, oxidative stress, biosynthesis and metabolism, proteases, cell proliferation, cell differentiation, and apoptosis. We also found that GAPDH, which was downregulated in aged skin samples, was the top hub gene in a protein-protein interaction network analysis. Some of the DEPs identified herein had been previously correlated with aging of the skin and other organs, while others may represent novel age-related entities. Our non-invasive proteomics analysis of human epidermal proteins may guide future research on skin aging to help develop treatments for age-related skin conditions and rejuvenation.

Challenges in the Practice of Sexual Medicine in the Time of COVID-19 in China.

BACKGROUND: In March 2020, the World Health Organization declared coronavirus disease 2019 (COVID-19), which is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a pandemic. Currently, data on changes in sexual behavior during the COVID-19 outbreak are limited. AIM: The present study aimed to obtain a preliminary understanding of the changes in people's sexual behavior, as a result of the pandemic, and explore the context in which they manifest. METHODS: A convenience sample of 270 men and 189 women who completed an online survey consisting of 12 items plus an additional question were included in the study. OUTCOMES: The study outcomes were obtained using a study-specific questionnaire to assess the changes in people's sexual behavior. RESULTS: While there was a wide range of individual responses, our results showed that 44% of participants reported a decrease in the number of sexual partners and about 37% of participants reported a decrease in sexual frequency. Multiple regression analysis showed that age, partner relationship, and sexual desire were closely related to sexual frequency. In addition, we found that most individuals with risky sexual experiences had a rapid reduction in risky sexual behavior. CLINICAL IMPLICATIONS: The current findings contribute to identifying another potential health implication associated with the COVID-19 pandemic and report preliminary evidence of the need to provide potential interventions for the population. STRENGTH & LIMITATIONS: This study is the first to perform a preliminary exploration of sexual behavior during the COVID-19 outbreak. The generalizability of the results is limited, given that only a small convenience sample was used. CONCLUSION: During the height of the COVID-19 outbreak, overall sexual activity, frequency, and risky behaviors declined significantly among young men and women in China. Li W, Li G, Xin C, et al. Challenges in the Practice of Sexual Medicine in the Time of COVID-19 in China. J Sex Med 2020;17:1225-1228.

Non­invasive proteome­wide quantification of skin barrier­related proteins using label­free LC­MS/MS analysis.

A number of epidermal proteins are closely related to skin barrier function, the abnormalities of which can lead to specific skin diseases. These proteins must be quantified to further investigate the changes in the skin barrier between healthy and disease states. However, the non­invasive and proteome­wide quantification of skin proteins without any labelling steps remains a challenge. In this study, 3M medical adhesive tapes were used to obtain skin samples from volunteers. Proteins were extracted from fresh skin samples and digested with trypsin. Each tryptic peptide was analysed in three replicates using liquid chromatography with tandem mass spectrometry analysis and label­free quantification. The data were searched against the Human Universal Protein Resource (UniProt) to match with known proteins. Using this method, 1,157 skin proteins recorded in the UniProt were quantified. A total of 50 identical proteins were identified in the three replicate analyses of all samples with no significant differences in abundance. The results provided an objective metric for further study of skin ageing and various skin diseases. Specifically, the non­invasive proteome­wide method used in this study can be applied to future studies of skin diseases related to barrier destruction by monitoring the changes in the levels of epidermal proteins.

Detection and Analysis of Ceramide in Skin and Blood in a Healthy Chinese Population.

To explore the significance of ceramide in the skin barrier and its potential utility within the cosmetics industry, an accurate and high-speed method was used to detect the types of ceramides in the skin and blood of a healthy Chinese population. Forearm cortical skin stratum corneum samples were obtained from four healthy subjects using a noninvasive method. In addition, these subjects were collected intravenously to obtain blood samples. Ceramides were detected in skin and blood samples using high-performance liquid chromatography coupled with specialized high-resolution Fourier Transform mass spectrometry machine. Data were analyzed using full-flow lipid analysis software. Peaks representing ceramides were detected in all skin samples and some blood samples. The results show that ceramides in skin are predominantly long-chain ceramides, but mainly short-chain in the blood. Simple and fast qualitative and quantitative analysis of ceramide in the skin and blood provides a basis for the precise addition of ceramide in future skin care products and the metabolic regulation and prevention of various diseases.

Noninvasive analysis of skin proteins in healthy Chinese subjects using an Orbitrap Fusion Tribrid mass spectrometer.

OBJECTIVE: The objective of this study was to perform noninvasive analysis of skin proteins in a healthy Chinese population using label-free nanoflow liquid chromatography-mass spectrometry (nLC-MS). MATERIALS AND METHODS: Five consecutive tape strippings were obtained from the volar forearm skin of healthy Chinese subjects. Proteins were extracted, and trypsin-digested peptides were analyzed by a nanochromatography instrument coupled to an Orbitrap Fusion Tribrid mass spectrometer. Data-dependent acquisition allowed protein identification, which was performed by using Proteome Discoverer software (v2.2). RESULTS: In this study, we identified 80 common proteins that were expressed in the skin of healthy Chinese volunteers and divided these proteins into 16 categories, including keratins, cornified envelope proteins, and enzymes associated with substance metabolism. These proteins were closely associated with multiple functions of the skin barrier. CONCLUSION: This study provides a noninvasive method to analyze healthy human epidermal proteins, which are closely associated with the skin barrier. In addition, this study provides a reference for further studies on the application of proteomic technologies to investigate the role of human epidermal proteins in health and disease.