Age-dependent sequential increase of senescent cells in the skin

Skin Aging and the Upcoming Role of Ferroptosis in Geroscience

The skin is considered the most important organ system in mammals, and as the population ages, it is important to consider skin aging and anti-aging therapeutic strategies. Exposure of the skin to various insults induces significant changes throughout our lives, differentiating the skin of a young adult from that of an older adult. These changes are caused by a combination of intrinsic and extrinsic aging. We report the interactions between skin aging and its metabolism, showing that the network is due to several factors. For example, iron is an important nutrient for humans, but its level increases with aging, inducing deleterious effects on cellular functions. Recently, it was discovered that ferroptosis, or iron-dependent cell death, is linked to aging and skin diseases. The pursuit of new molecular targets for ferroptosis has recently attracted attention. Prevention of ferroptosis is an effective therapeutic strategy for the treatment of diseases, especially in old age. However, the pathological and biological mechanisms underlying ferroptosis are still not fully understood, especially in skin diseases such as melanoma and autoimmune diseases. Only a few basic studies on regulated cell death exist, and the challenge is to turn the studies into clinical applications.

Comparative study on the age-related incidence of seborrheic keratosis and verruca plana in patients with verruca plana-like lesions

Seborrheic keratosis (SK) is a common skin disease in the elderly. However, in cases where SK presenting as multiple skin-colored or clustered lesions can be easily misdiagnosed as verruca plana (VP), especially in the young population. This retrospective study investigated the prevalence of SK and VP in the lesions that appear clinically similar to VP according to age. We examined the pathology slides of the skin tissue and photographs of patients who were clinically suspected to have VP. A total of 503 patients were included in the study, out of which 174 patients were finally diagnosed with SK (34.6%) and 132 with VP (26.2%). The mean ages of the SK- and VP-diagnosed group were 39.3 and 35.4 years, respectively. SK had a higher prevalence among individuals older than 30 years, and relative frequency of SK should not be ignored in patients with a grouped distribution in their 20 s and 30 s. Therefore, our study suggests that multiple verrucous skin-colored to brownish plaques are also commonly diagnosed as SK in young people as well as VP, and the prevalence of SK and VP may not always depend solely on chronological aging, and the prevalence of SK among young people may be higher than commonly believed stereotypes suggest.

The Cross Talk between Cellular Senescence and Melanoma: From Molecular Pathogenesis to Target Therapies

Melanoma is a malignant skin tumor that originates from melanocytes. The pathogenesis of melanoma involves a complex interaction that occurs between environmental factors, ultraviolet (UV)-light damage, and genetic alterations. UV light is the primary driver of the skin aging process and development of melanoma, which can induce reactive oxygen species (ROS) production and the presence of DNA damage in the cells, and results in cell senescence. As cellular senescence plays an important role in the relationship that exists between the skin aging process and the development of melanoma, the present study provides insight into the literature concerning the topic at present and discusses the relationship between skin aging and melanoma, including the mechanisms of cellular senescence that drive melanoma progression, the microenvironment in relation to skin aging and melanoma factors, and the therapeutics concerning melanoma. This review focuses on defining the role of cellular senescence in the process of melanoma carcinogenesis and discusses the targeting of senescent cells through therapeutic approaches, highlighting the areas that require more extensive research in the field.

Skin-Aging Pigmentation: Who Is the Real Enemy?

Skin aging is induced and sustained by chronological aging and photoaging. Aging skin pigmentation such as mottled pigmentation (senile lentigo) and melasma are typical signs of photoaging. The skin, like other human organs, undergoes cellular senescence, and senescent cells in the skin increase with age. The crosstalk between melanocytes as pigmentary cells and other adjacent types of aged skin cells such as senescent fibroblasts play a role in skin-aging pigmentation. In this review, we provide an overview of cellular senescence during the skin-aging process. The discussion also includes cellular senescence related to skin-aging pigmentation and the therapeutic potential of regulating the senescence process.