Time Is Running Out: The Circadian Clock Suggests Sex and Aging Differences in Human Epidermis
Day and night have long guided daily activities in our lives. Before time-keeping innovations such as sundials and clocks, humans maintained schedules by merely opening their eyes as the sun rose in the sky. Unbeknownst to them, their internal biological clock was maintaining regulation of their bodily functions throughout the course of the day through the trillions of cells that comprise the human body. This endogenous cellular process is referred to as one ’s circadian or biological rhythm and oscillates over an approximately 24-hour period, often portrayed as a cosine wave. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 15, 2024 Category: Dermatology Authors: Rachel Bernstein, Shobhan Gaddameedhi Tags: Commentary Source Type: research

Advances in Skin-on-a-Chip Technologies for Dermatological Disease Modeling
Skin-on-a-chip (SoC) technologies are emerging as a paradigm shift in dermatology research by replicating human physiology in a dynamic manner not achievable by current animal models. Although animal models have contributed to successful clinical trials, their ability to predict human outcomes remains questionable, owing to inherent differences in skin anatomy and immune response. Covering areas including infectious diseases, autoimmune skin conditions, wound healing, drug toxicity, aging, and antiaging, SoC aims to circumvent the inherent disparities created by traditional models. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 15, 2024 Category: Dermatology Authors: Seo Won Cho, Hamza Malick, Soo Jung Kim, Alessandro Grattoni Tags: Review Source Type: research

Emerging Role of Fibroblasts in Vitiligo: A Formerly Underestimated Rising Star
Vitiligo is a disfiguring depigmentation disorder characterized by loss of melanocytes. Although numerous studies have been conducted on the pathogenesis of vitiligo, the underlying mechanisms remain unclear. Although most studies have focused on melanocytes and keratinocytes, growing evidence suggests the involvement of dermal fibroblasts, residing deeper in the skin. This review aims to elucidate the role of fibroblasts in both the physiological regulation of skin pigmentation and their pathological contribution to depigmentation, with the goal of shedding light on the involvement of fibroblasts in vitiligo. (Source: Jou...
Source: Journal of Investigative Dermatology - March 15, 2024 Category: Dermatology Authors: Yue Wu, Yiwen Yang, Yi Lin, Yuecen Ding, Ziqi Liu, Leihong Xiang, Mauro Picardo, Chengfeng Zhang Tags: Review Source Type: research

Endothelial Dysfunction in Psoriasis: An Integrative Review
Vascular endothelial cells (ECs), the inner layer of blood vessels, were previously considered to be a passive lining that facilitates cellular and molecular exchange. However, recent studies have revealed that ECs can respond to various stimuli and actively regulate vascular function and skin inflammation. Specific subtypes of ECs are known to have significant roles in a diverse range of physiological and pathological processes in the skin. This review suggests that EC dysfunction is both causal and consequential in the pathogenesis of psoriasis. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 15, 2024 Category: Dermatology Authors: Qingyang Li, Bingyu Pang, Erle Dang, Gang Wang Tags: Review Source Type: research

Efficacy and Safety of Rilzabrutinib in Pemphigus: PEGASUS Phase 3 Randomized Study
Pemphigus is a rare, but life-threatening autoimmune disease requiring long-term treatment that minimizes corticosteroid (CS) exposure while providing consistent disease control. The phase 2 pemphigus study of oral, reversible, covalent Bruton tyrosine kinase (BTK) inhibitor rilzabrutinib demonstrated rapid and sustained efficacy with well-tolerated safety. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 15, 2024 Category: Dermatology Authors: Dedee F. Murrell, Fr édéric Caux, Aikaterini Patsatsi, Owen Hagino, Lidia Rudnicka, Snejina Vassileva, Soner Uzun, Jenny Ye, Karl Yen, Puneet Arora, Steven G. Gourlay, Pascal Joly, Victoria P. Werth Tags: Original Article Source Type: research

Modeling Wound Chronicity In  Vivo: The Translational Challenge to Capture the Complexity of Chronic Wounds
In an aging society with common lifestyle-associated health issues such as obesity and diabetes, chronic wounds pose a frequent challenge that physicians face in everyday clinical practice. Therefore, nonhealing wounds have attracted much scientific attention. Several in  vitro and in vivo models have been introduced to deepen our understanding of chronic wound pathogenesis and amplify therapeutic strategies. Understanding how wounds become chronic will provide insights to reverse or avoid chronicity. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 13, 2024 Category: Dermatology Authors: Anna-Lisa Pignet, Marlies Schellnegger, Andrzej Hecker, Lars-Peter Kamolz, Petra Kotzbeck Tags: Review Source Type: research

Calpain inhibition protects against UVB-induced degradation of dermal-epidermal junction-associated proteins
The skin is a highly regenerative tissue that harbors multiple reservoirs of stem cells, enabling it to efficiently repair and regenerate (Fuchs 2008). However, despite its regenerative capacity, the skin undergoes aging, leading to compromised barrier function, reduced mechano-resilience, and impaired wound healing (Quan 2023). Histological analyses have indicated that alterations in the extracellular matrix (ECM) of the skin are key features of aging (Quan 2023). These alterations affect the load-bearing dermal interstitial ECM through reduced collagen levels and increased fragmentation of collagen and elastin fibers (Qu...
Source: Journal of Investigative Dermatology - March 13, 2024 Category: Dermatology Authors: Iva Doleckova, Tinka Vidovic, Lenka Jandova, Christine Gretzmeier, Alexander A. Navarini, Michael R. MacArthur, Orcun Goksel, Alexander Nystr öm, Collin Y. Ewald Tags: Letters to the Editor Source Type: research

SPRY1 deficiency in keratinocytes induces follicular melanocyte stem cells migration to epidermis through p53/SCF/C-KIT signaling
The function and survival of melanocytes is regulated by an elaborate network of paracrine factors synthesized mainly by epidermal keratinocytes. Keratinocytes and melanocytes respond to UV exposure by eliciting a tanning response. However, how keratinocytes and melanocytes interact in the absence of UV exposure is unknown. Here, we demonstrate that after SPRY1 knockout in epidermal keratinocytes, melanocyte stem cells (McSCs) in the hair follicle exit the niche without depleting the pool of these cells. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 8, 2024 Category: Dermatology Authors: Ying-Zhe Cui, Fan Xu, Yuan Zhou, Zhao-Yuan Wang, Xing-Yu Yang, Ni-Chang Fu, Xi-Bei Chen, Yu-Xin Zheng, Xue-Yan Chen, Li-Ran Ye, Ying-Ying Li, Xiao-Yong Man Tags: Original Article Source Type: research

Monocyte-to-high-density lipoprotein ratio is associated with systemic inflammation, insulin resistance and coronary subclinical atherosclerosis in psoriasis: results from 2 observational cohorts
Systemic inflammation or insulin resistance drive atherosclerosis. However, they are difficult to capture for assessing cardiovascular risk in clinical settings. The monocyte-to-HDL ratio (MHR) is an accessible biomarker that integrates inflammatory and metabolic information and which has been associated with poorer cardiovascular outcomes. Our aim was to evaluate the association of MHR with the presence of subclinical atherosclerosis in patients with psoriasis. The study involved a European and an American cohort including 405 patients with the disease. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 7, 2024 Category: Dermatology Authors: Emilio Berna-Rico, Carlota Abbad-Jaime de Aragon, Asuncion Ballester-Martinez, Javier Perez-Bootello, Jorge Solis, Leticia Fernandez-Friera, Mar Llamas-Velasco, Maria Castellanos-Gonzalez, Maria G. Barderas, Carlos Azcarraga-Llobet, Emilio Garcia-Mouronte Tags: Original Article Source Type: research

Genetic analysis of perceived youthfulness reveals differences in how men's and women ’s age is assessed
Skin aging is a natural process that occurs over time, but can be accelerated by sun exposure. Measuring skin age in a large population can provide insight into the extent of skin damage from sun exposure and skin cancer risk. Understanding the genetics of skin aging, within and across sexes, could improve our understanding of the genetic drivers of both skin aging and skin cancer. We used UK Biobank data to examine the genetic overlap between perceived youthfulness and traits relevant to actinic photoaging. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 7, 2024 Category: Dermatology Authors: Nathan Ingold, Mathias Seviiri, Jue-Sheng Ong, Scott Gordon, Rachel E. Neale, David C. Whiteman, Catherine M. Olsen, Stuart MacGregor, Matthew H. Law Tags: Original Article Source Type: research

CASZ1 is Essential for Skin Epidermal Terminal Differentiation
The barrier function of skin epidermis is crucial for our bodies to interface with the environment. As epidermis continuously turns over throughout the lifetime, this barrier must be actively maintained by regeneration. Although several transcription factors have been established as essential activators in epidermal differentiation, it is unclear if additional factors remain to be identified. Here, we show that CASZ1, a multi-zinc-finger transcription factor previously characterized in non-epithelial cell types, shows highest expression in skin epidermis. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 6, 2024 Category: Dermatology Authors: Stephenie H. Droll, Benny J. Zhang, Maxwell C. Levine, Celia Xue, Patric J. Ho, Xiaomin Bao Tags: Original Article Source Type: research

Tumor-intrinsic galectin-3 suppresses melanoma metastasis
Melanoma poses a poor prognosis with high mortality rates upon metastasis. Exploring molecular mechanisms governing melanoma progression paves the way for developing novel approaches to control melanoma metastasis and ultimately enhance patient survival rates. Extracellular galectin-3 (Gal-3) has emerged as a pleiotropic promoter of melanoma metastasis, exerting varying activities depending on its interacting partner. However, whether intracellular Gal-3 promotes melanoma aggressive behavior remains unknown. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 5, 2024 Category: Dermatology Authors: Norhan B.B. Mohammed, Lee Seng Lau, Joseph Souchak, Shi Qiu, Manmeet S. Ahluwalia, Iman Osman, Charles J. Dimitroff Tags: Original Article Source Type: research

The Promises and Perils of Foundation Models in Dermatology
Foundation models (FM), which are large-scale artificial intelligence (AI) models that can complete a range of tasks, represent a paradigm shift in AI. These versatile models encompass large language models, vision-language models, and multimodal models. Although these models are often trained for broad tasks, they have been applied either out of the box or after additional fine tuning to tasks in medicine, including dermatology. From addressing administrative tasks to answering dermatology questions, these models are poised to have an impact on dermatology care delivery. (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 4, 2024 Category: Dermatology Authors: Haiwen Gui, Jesutofunmi A. Omiye, Crystal T. Chang, Roxana Daneshjou Tags: Review Source Type: research

Excoriation disorder is characterized by systemic glutamatergic dysfunction
Excoriation disorder (ED), also known as neurotic excoriations, is a psychocutaneous disorder characterized by repetitive, compulsive picking of the skin leading to secondary tissue damage (Brown et al., 2015, Grant et al., 2012, Roh et al., 2022). ED carries an estimated prevalence of 1.4% (Keuthen et al., 2010), and is associated with significant social dysfunction, as patients often spend several hours each day performing compulsive behaviors leading to absence from work, school, or other social events (Grant et al., 2012). (Source: Journal of Investigative Dermatology)
Source: Journal of Investigative Dermatology - March 4, 2024 Category: Dermatology Authors: Zachary A. Bordeaux, Sriya V. Reddy, Emily Z. Ma, Hannah Cornman, Thomas Pritchard, Melika Marani, Weiying Lu, Shenghao Guo, Cissy Zhang, Pratik Khare, Anne Le, Madan M. Kwatra, Shawn G. Kwatra Tags: Letters to the Editor Source Type: research

Similar alterations of the stratum corneum ceramide profile in atopic dermatitis, psoriasis and ichthyosis: results from a systematic review and meta-analysis.
The intracellular lipid matrix of the stratum corneum is critical for the skin barrier function and consists mainly of cholesterol, fatty acids and ceramides (Kihara 2016). Ceramides represent a heterogeneous class of lipids with varying headgroups, carbon chain lengths and degree of unsaturation (Kawana et al. 2020). The composition of the ceramide fraction is altered in atopic dermatitis (AD), psoriasis (PSO) and ichthyosis (ICHT), among other dermatoses (Kihara 2016). Here, we aimed to characterize the similarities between the stratum corneum ceramide profile in these indications using a systematic search strategy and m...
Source: Journal of Investigative Dermatology - March 4, 2024 Category: Dermatology Authors: Jannik Rousel, Catherine Mergen, Jan W. Schoones, Tessa Niemeyer-van der Kolk, Martijn B.A. van Doorn, Joke A. Bouwstra, Jeroen van Smeden, Robert Rissmann, the Next Generation ImmunoDermatology Consortium Tags: Letters to the Editor Source Type: research