The skin's role as a mirror of internal disease has long been established, with clear associations to several internal organs. However, its relationship with bone is less well known. There are clear physiological links between the two organ systems, with their shared factors crucial to maintain structural integrity and homeostasis. Collagen, vitamin D homeostasis, aging, medications, and the gut microbiome are all factors that impact both skin and bone. It is of utmost importance that the skin-bone axis be adequately understood to support a healthy aging process. In this review, we discuss the multiple facets related to skin and bone health, their interconnectivity, as well as the importance of promoting whole body health.
Exosomes are nanosized extracellular vesicles increasingly recognized as regulators of cutaneous biology with direct clinical relevance. In dermatology, they influence keratinocyte and fibroblast proliferation, pigmentation pathways, and immune modulation in disorders such as atopic dermatitis and cutaneous lupus. Their strongest evidence lies in wound healing, where exosomes accelerate closure by dampening proinflammatory cytokines (tumor necrosis factor-α, interleukin-6, matrix metalloproteinase-9), enhancing angiogenesis through vascular endothelial growth factor signaling, and improving collagen deposition and scar quality. Early studies also support their role in regenerative skin care, including reversal of photoaging, improved elasticity, and stimulation of hair follicle growth. Although current use is limited to cosmetic applications without United States Food and Drug Administration (FDA) approval, international experience suggests therapeutic potential in chronic wounds, inflammatory dermatoses, and pigmentation disorders. For clinicians, exosomes represent a novel biologic platform that may soon complement established therapies, underscoring the importance of ongoing translational research and regulatory clarity.
Zasocitinib is a novel highly selective tyrosine kinase 2 (TYK2) inhibitor that is in late phase development for the treatment of psoriasis and psoriatic arthritis. This article will review its efficacy, safety and tolerability. Currently, deucravacitinib is the only TYK2 inhibitor with regulatory approval from most major authorities. Zasocitinib offers potential benefits, as it has higher target selectivity and affinity of the Janus homology 2 (JH2) domain of TYK2 as compared to deucravacitinib. This selectivity leads to minimal inhibition of Janus kinase (JAK) 1, JAK2 and JAK3 (JAK1-3), and therefore may result in less off-target effects that have been associated with other molecules.
Hyperhidrosis (HH), a condition characterized by excessive sweating beyond thermoregulation, significantly impairs quality of life. Conventional medications to treat HH include aluminum chloride hexahydrate, systemic anticholinergics, and botulinum toxin injections. New treatments have emerged including glycopyrronium bromide, sofpironium bromide, targeted alkali thermolysis, and microwave devices. This paper reviews the mechanism of action, efficacy, safety, and practical considerations associated with these treatments.
