Effects of ozone on stratum corneum lipid integrity and assembly

Exposure to ambient oxidant pollution associated with ceramide changes and cardiometabolic responses

Evidence of impact of ambient oxidant pollution on cardiometabolic responses remains limited. We aimed to examine associations of oxidant pollutants with cardiometabolic responses, and effect modification by ceramides. During 2019-2020, 152 healthy adults were visited 4 times in Beijing, China, and indicators of ceramides, glucose homeostasis, and vascular function were measured. We found significant increases in ceramides of 13.9% (p = 0.020) to 110.1% (p = 0.005) associated with an interquartile increase in oxidant pollutants at prior 1-7 days. Exposure to oxidant pollutants was also related to elevations in insulin and reductions in adiponectin, and elevations in systolic and diastolic blood pressure. Further, stratified analyses revealed larger changes in oxidant pollutant related cardiometabolic responses among participants with higher ceramide levels compared to those with lower levels. Our findings suggested cardiometabolic effects associated with exposure to oxidant pollutants, which may be modified by ceramide levels.

Current insights into skin lipids and their roles in cutaneous health and disease

PURPOSE OF REVIEW

The unique and complex array of cutaneous lipids include essential components of the skin structure and signalling molecules mediating homeostasis and inflammation. Understanding skin lipid biology and metabolism can support our comprehension of health and disease, including systemic conditions with cutaneous involvement.

RECENT FINDINGS

Lipids found on the skin surface, produced by both the host and resident microbes, maintain and regulate the skin microbiome and the epidermal barrier, whilst altered contributions from either source can be detrimental to skin health. The unique lipid composition of the epidermal barrier is essential for its function, and recent studies have expanded our understanding of epidermal ceramide production. This has been supported by improved models available for skin research, including organotypic skin models enabling in-vitro production of complex acylceramides for the first time, and model systems facilitating in-silico exploration of the lipid profile changes observed in clinical samples. Studies have revealed further involvement of lipid mediators such as eicosanoids in cutaneous inflammation, as well as immune regulation in both healthy and diseased skin.

SUMMARY

Skin lipids offer exciting opportunities as therapeutic targets for many conditions, whether through topical interventions or nutritional supplementation.

Effects of Air Pollution on Cellular Senescence and Skin Aging

The human skin is exposed daily to different environmental factors such as air pollutants and ultraviolet (UV) light. Air pollution is considered a harmful environmental risk to human skin and is known to promote aging and inflammation of this tissue, leading to the onset of skin disorders and to the appearance of wrinkles and pigmentation issues. Besides this, components of air pollution can interact synergistically with ultraviolet light and increase the impact of damage to the skin. However, little is known about the modulation of air pollution on cellular senescence in skin cells and how this can contribute to skin aging. In this review, we are summarizing the current state of knowledge about air pollution components, their involvement in the processes of cellular senescence and skin aging, as well as the current therapeutic and cosmetic interventions proposed to prevent or mitigate the effects of air pollution in the skin.