Microbiota-Independent Spontaneous Dermatitis Associated With Increased Sebaceous Lipid Production in Tmem79-Deficient Mice

Unlocking the therapeutic potential of TRPV3: Insights into thermosensation, channel modulation, and skin homeostasis involving TRPV3

Recent insights reveal the significant role of TRPV3 in warmth sensation. A novel finding elucidated how thermosensation is affected by TRPV3 membrane abundance that is modulated by the transmembrane protein TMEM79. TRPV3 is a warmth-sensitive ion channel predominantly expressed in epithelial cells, particularly skin keratinocytes. Multiple studies investigated the roles of TRPV3 in cutaneous physiology and pathophysiology. TRPV3 activation by innocuous warm temperatures in keratinocytes highlights its significance in temperature sensation, but whether TRPV3 directly contributes to warmth sensations in vivo remains controversial. This review explores the electrophysiological and structural properties of TRPV3 and how modulators affect its intricate regulatory mechanisms. Moreover, we discuss the multifaceted involvement of TRPV3 in skin physiology and pathology, including barrier formation, hair growth, inflammation, and itching. Finally, we examine the potential of TRPV3 as a therapeutic target for skin diseases and highlight its diverse role in maintaining skin homeostasis.

Adding Fuel to the Fire? The Skin Microbiome in Atopic Dermatitis

Atopic dermatitis (AD) is a multifactorial, heterogeneous disease characterized by epidermal barrier dysfunction, immune system dysregulation, and skin microbiome alterations. Skin microbiome studies in AD have demonstrated that disease flares are associated with microbial shifts, particularly Staphylococcus aureus predominance. AD-associated S. aureus strains differ from those in healthy individuals across various genomic loci, including virulence factors, adhesion proteins, and proinflammatory molecules-which may contribute to complex microbiome barrier-immune system interactions in AD. Different microbially based treatments for AD have been explored, and their future therapeutic successes will depend on a deeper understanding of the potential microbial contributions to the disease.

Involvement of skin TRPV3 in temperature detection regulated by TMEM79 in mice

TRPV3, a non-selective cation transient receptor potential (TRP) ion channel, is activated by warm temperatures. It is predominantly expressed in skin keratinocytes, and participates in various somatic processes. Previous studies have reported that thermosensation in mice lacking TRPV3 was impaired. Here, we identified a transmembrane protein, TMEM79, that acts as a negative regulator of TRPV3. Heterologous expression of TMEM79 was capable of suppressing TRPV3-mediated currents in HEK293T cells. In addition, TMEM79 modulated TRPV3 translocalization and promoted its degradation in the lysosomes. TRPV3-mediated currents and Ca²⁺ influx were potentiated in primary mouse keratinocytes lacking TMEM79. Furthermore, TMEM79-deficient male mice preferred a higher temperature than did wild-type mice due to elevated TRPV3 function. Our study revealed unique interactions between TRPV3 and TMEM79, both in vitro and in vivo. These findings support roles for TMEM79 and TRPV3 in thermosensation.

Dissecting skin microbiota and microenvironment for the development of therapeutic strategies

The skin is a pivotal barrier between the human body and the environment, and is a habitat for numerous microorganisms. While host-microbiota interactions in the skin are essential for homeostasis, disturbances in microbial composition and the abnormal growth of certain bacteria are associated with various diseases. Here, we identify strains and communities of skin commensals that contribute to or impair skin barrier function. Furthermore, we discuss the skin microenvironments suitable for specific microbiota that exert therapeutic effects and suggest focus areas for the prospective development of therapeutic strategies using bacterial agents. Finally, we highlight recent efforts to treat skin diseases associated with live bacteria.