Repigmentation and new growth of hairs after anti-interleukin-17 therapy with secukinumab for psoriasis

Premature hair graying: a multifaceted phenomenon

Premature hair graying (PHG) is the early loss of natural hair color, influenced by genetic, biological, and environmental factors. This review discusses the significant psychological impacts of PHG and explores its underlying mechanisms, related health conditions, and available treatments. The review examines the roles of genetics, oxidative stress, and lifestyle factors such as smoking and diet in premature graying. It also considers associated medical conditions and current and emerging treatment options. This overview aims to improve understanding of PHG and its broader implications.

Reversing Gray Hair: Inspiring the Development of New Therapies Through Research on Hair Pigmentation and Repigmentation Progress

Hair graying is a common and visible sign of aging resulting from decreased or absence of melanogenesis. Although it has been established that gray hair greatly impacts people's mental health and social life, there is no effective countermeasure other than hair dyes. It has long been thought that reversal of gray hair on a large scale is rare. However, a recent study reported that individual gray hair darkening is a common phenomenon, suggesting the possibility of large-scale reversal of gray hair. In this article, we summarize the regulation mechanism of melanogenesis and review existing cases of hair repigmentation caused by several factors, including monoclonal antibodies drugs, tyrosine kinase inhibitors (TKIs), immunomodulators, other drugs, micro-injury, and tumors, and speculate on the mechanisms behind them. This review offers some insights for further research into the modulation of melanogenesis and presents a novel perspective on the development of clinical therapies, with emphasis on topical treatments.

Cerebrolysin induces hair repigmentation associated to MART-1/Melan-A reactivation

Hair graying, a prototypical sign of human aging, is a progressive loss of pigmentation from growing hair shafts caused by disease and as a side effect of medications. Cerebrolysin is a neuropeptide preparation that mimics the effect of endogenous neurotrophic factors. Cerebrolysin has been widely used in neurologic conditions, such as cerebral stroke, Alzheimer's disease, and dementia, among others. Cerebrolysin treatment has achieved to regain or maintain the cognitive ability of affected patients; however, up to date, there are no reports about the reactivation of hair pigmentation. We describe a previously not described effect occurring on patients receiving Cerebrolysin treatment for neurologic diseases and whether this effect is associated in reactivation of melanocytes and melanin expression. Here, we report five patients (mean age, 70.6 years), who also had age-related hair graying and scalp hair repigmentation during Cerebrolysin treatment. Macroscopic analysis revealed hair repigmentation consisted in diffuse darkening of the scalp hair. Impregnation and immunostaining analysis were performed on scalp biopsies taken before and after Cerebrolysin treatment; the results showed greater melanin and melanocyte marker MART-1/Melan-A staining following Cerebrolysin treatment. We present, to our knowledge, the first report on hair repigmentation is a previously not described effect occurring following Cerebrolysin treatment.

The dark side of the moon: the immune-mediated adverse events of IL-17A/IL-17R inhibition

As aberrant IL-17 signaling plays a critical role in the pathogenesis of psoriasis, biologic agents targeting this pathway have become an important weapon against this disease. Some biologic agents such as IL-17 inhibitors (secukinumab and ixekizumab) and the IL-17 receptor (IL17R) inhibitor (brodalumab) are relatively safe, tolerable and efficacious drugs. Nevertheless, side effects of IL-17 pathway inhibition occur. This review focuses on the dermatological manifestations linked to these treatments. Paradoxical psoriasis and atopic-like eczema may be the most common cutaneous adverse events, while manifestations such as neutrophilic dermatoses, hypersensitivity reactions, lichenoid eruptions, vasculitides, bullous diseases, lupus-like reactions, pigmentation disorders, adnexal diseases and granulomatous dermatoses have been described less frequently.

Updates on the Treatment of Erythrodermic Psoriasis

Erythrodermic psoriasis (EP) is a rare variant of psoriasis, which is potentially life threatening and often resistant to conventional therapy. Biologics have revolutionized the treatment of plaque-type psoriasis, and shown promise in EP. However, due to the lack of head-to-head studies and the rarity of EP, no high level evidence-based treatment guidelines for EP have been established, and the evidence of treatment of EP is limited to case reports or small case series. Here, we present a narrative review focusing on the up-to-date information for the treatment of EP.

Exploring the human hair follicle microbiome

Human hair follicles (HFs) carry complex microbial communities that differ from the skin surface microbiota. This likely reflects that the HF epithelium differs from the epidermal barrier in that it provides a moist, less acidic, and relatively ultraviolet light-protected environment, part of which is immune-privileged, thus facilitating microbial survival. Here we review the current understanding of the human HF microbiome and its potential physiological and pathological functions, including in folliculitis, acne vulgaris, hidradenitis suppurativa, alopecia areata and cicatricial alopecias. While reviewing the main human HF bacteria (such as Propionibacteria, Corynebacteria, Staphylococci and Streptococci), viruses, fungi and parasites as human HF microbiome constituents, we advocate a broad view of the HF as an integral part of the human holobiont. Specifically, we explore how the human HF may manage its microbiome via the regulated production of antimicrobial peptides (such as cathelicidin, psoriasin, RNAse7 and dermcidin) by HF keratinocytes, how the microbiome may impact on cytokine and chemokine release from the HF, and examine hair growth-modulatory effects of antibiotics, and ask whether the microbiome affects hair growth in turn. We highlight major open questions and potential novel approaches to the management of hair diseases by targeting the HF microbiome.

Increased Circulatory Interleukin-17A Levels in Patients with Progressive and Leukotrichial Vitiligo

Background

Vitiligo is a chronic condition characterized by skin depigmentation. Although not life-threatening, it significantly impacts quality of life. The pathophysiology of vitiligo remains poorly understood, and treatment options are limited. Mounting evidence supports the importance of autoreactive T cells and, particularly interleukin-17A- (IL-17A-) secreting Th17 cells, in vitiligo. IL-17A targeting has been proven successful in various inflammatory dermatological conditions, including psoriasis and lupus erythematosus.

Objective

We evaluated the relationship between serum levels of IL-17A and the clinicopathological characteristics of Vietnamese vitiligo patients.

Methods

In this cross-sectional study, we analyzed data from 52 nonsegmental vitiligo patients and 50 age- and sex-matched healthy individuals. Serum levels of IL-17A were measured using an enzyme-linked immunosorbent assay. We evaluated the correlation between IL-17A levels and clinical characteristics including leukotrichia, disease duration, vitiligo activity, and body surface area involvement.

Results

Patients with progressive vitiligo had significantly higher IL-17A levels than patients with stable vitiligo (P = 0.014) or healthy individuals (P = 0.002). In addition, serum IL-17A levels were higher in vitiligo patients with leukotrichia than in patients without it (P = 0.04). Furthermore, serum IL-17A levels were negatively correlated with age (r = -0.39, P = 0.004) and age of onset (r = -0.33, P = 0.016) in vitiligo patients.

Conclusions

Higher serum levels of IL-17A in patients with progressive vitiligo and leukotrichia suggest a potential role of IL-17A in melanocyte destruction in the epidermis and the follicular matrix.

The biology of human hair greying

Hair greying (canities) is one of the earliest, most visible ageing-associated phenomena, whose modulation by genetic, psychoemotional, oxidative, senescence-associated, metabolic and nutritional factors has long attracted skin biologists, dermatologists, and industry. Greying is of profound psychological and commercial relevance in increasingly ageing populations. In addition, the onset and perpetuation of defective melanin production in the human anagen hair follicle pigmentary unit (HFPU) provides a superb model for interrogating the molecular mechanisms of ageing in a complex human mini-organ, and greying-associated defects in bulge melanocyte stem cells (MSCs) represent an intriguing system of neural crest-derived stem cell senescence. Here, we emphasize that human greying invariably begins with the gradual decline in melanogenesis, including reduced tyrosinase activity, defective melanosome transfer and apoptosis of HFPU melanocytes, and is thus a primary event of the anagen hair bulb, not the bulge. Eventually, the bulge MSC pool becomes depleted as well, at which stage greying becomes largely irreversible. There is still no universally accepted model of human hair greying, and the extent of genetic contributions to greying remains unclear. However, oxidative damage likely is a crucial driver of greying via its disruption of HFPU melanocyte survival, MSC maintenance, and of the enzymatic apparatus of melanogenesis itself. While neuroendocrine factors [e.g. alpha melanocyte-stimulating hormone (α-MSH), adrenocorticotropic hormone (ACTH), ß-endorphin, corticotropin-releasing hormone (CRH), thyrotropin-releasing hormone (TRH)], and micropthalmia-associated transcription factor (MITF) are well-known regulators of human hair follicle melanocytes and melanogenesis, how exactly these and other factors [e.g. thyroid hormones, hepatocyte growth factor (HGF), P-cadherin, peripheral clock activity] modulate greying requires more detailed study. Other important open questions include how HFPU melanocytes age intrinsically, how psychoemotional stress impacts this process, and how current insights into the gerontobiology of the human HFPU can best be translated into retardation or reversal of greying.

Generalized hypertrichosis due to secukinumab in a patient with moderate psoriasis: A case of serendipity or zemblanity?

After 4 months of therapy with secukinumab, a 67-year-old man with moderate psoriasis developed generalized hypertrichosis, along with PASI 90. The patient denied any drug intake, apart from secukinumab, nor applications of any creams. Moreover, this event did not really bother the patient, thus the therapy was not discontinued and the hypertrichosis is persisting as psoriasis' control.