Viable terminal scalp hair follicles constitute a necessary and sufficient biological end‐organ that conditions clinical efficacy of finasteride in males with male pattern hair loss without implying reversal of miniaturized follicles

Incorporation of Finasteride-Loaded Microspheres into Personalized Microneedle for Sustained Transdermal Delivery

Although finasteride (FNS) tablets are considered the most effective drug for the treatment of androgenetic alopecia (AGA), their clinical applications are limited due to the associated side effects including decreased libido, breast enlargement, and liver dysfunction. In this study, we have developed a personalized microneedle (PMN) with a double-layer structure that incorporates FNS-loaded microspheres (MPs) to accommodate irregular skin surfaces. This design enables the sustained release of FNS, thereby reducing potential side effects. The needle body was synthesized with high-strength hyaluronic acid (HA) as the base material substrate. The backing layer utilized methacrylate gelatin (GelMA) with specific toughness, enabling PMN to penetrate the skin while adapting to various skin environments. The length of PMN needles (10 × 10) was approximately 600 μm, with the bottom of the needles measuring about 330 μm × 330 μm. The distance between adjacent tips was around 600 μm, allowing the drug to penetrate the stratum corneum of the skin. The results of the drug release investigation indicated the sustained and regulated release of FNS from PMN, as compared to that of pure FNS and FNS-MPs. Further, the cytotoxicity assay demonstrates that PMS displays good cytocompatibility. Altogether, this mode of administration has immense potential for the development of delivery of other drugs, as well as in the medical field.

Following historical "tracks" of hair follicle miniaturisation in patterned hair loss: Are elastin bodies the forgotten aetiology?

Pattern hair loss (PHL) is a chronic regressive condition of the scalp, where follicular miniaturisation and decreased scalp hair coverage occurs in affected areas. In all PHL cases, there is a measurable progressive shortening of the terminal hair growth duration, along with reduced linear growth rates. In both genders, PHL initially shows an increase in short telogen hairs ≤30 mm in length, reflecting a cycle completion of under 6 months in affected terminal hair follicles. To understand the miniaturisation process, we re-examine the dynamics of miniaturisation and ask the question, "why do miniaturised hair follicles resist treatment?" In the light of recent developments in relation to hair regeneration, we looked back in the older literature for helpful clues "lost to time" and reprise a 1978 Hermann Pinkus observation of an array of elastin deposits beneath the dermal papilla following subsequent anagen/telogen transitions in male balding, originally described by Arao and Perkins who concluded that these changes provide a "morphologic marker of the entire biologic process in the balding scalp." Thus, we have reviewed the role of the elastin-like bodies in hair pathology and we propose that alterations in elastin architecture may contribute to the failure of vellus-like hair reverting back to their terminal status and may indicate a new area for therapeutic intervention.

Placebo-controlled dose-effect studies with topical minoxidil 2% or 5% in male-patterned hair loss treated with oral finasteride employing an analytical and exhaustive study protocol

Background

Drug trials for male‐pattern hair loss (MPHL) did not investigate hair cycling.

Materials and Methods

Male‐pattern hair loss volunteers (n = 22) took oral finasteride 1 mg daily with randomly either MTS5% or control lotion (1 mL/d). After 12 months on oral drug, 14 were randomized for a dose‐effect study of topical minoxidil 2% or 5%. Each 3‐month “on‐lotion” was followed by a 3‐month “off‐lotion.”

Results

Exogen release and anagen initiation from pre‐existing but functionally deficient follicles occurred mainly during combined dug treatment. Anagen initiation by topical minoxidil 5% could not be maintained by oral finasteride. As compared with control males, the compound index of hair growth raised from 30% at baseline up to 60% within 3 months of combined drug regimen which is better than oral drug only (no change) but still far beyond normalization of productivity (considered as 100%). There was no obvious transformation of miniaturized hair follicles into terminal hair‐producing follicles, and the activation of miniaturized hair follicles was not clinically relevant (slow growth and short duration of anagen).

Conclusions

Benefit with oral finasteride and topical 5% minoxidil (1 mL, 1 per day) resulted from initiation of anagen in deficient terminal follicles without increased growth rates.

Androgenetic alopecia: combing the hair follicle signaling pathways for new therapeutic targets and more effective treatment options

Introduction: In the past 30 years, only two drugs have received FDA approval for the treatment of androgenetic alopecia reflecting a lack of success in unraveling novel targets for pharmacological intervention. However, as our knowledge of hair biology improves, new signaling pathways and organogenesis processes are being uncovered which have the potential to yield more effective therapeutic modalities. Areas covered: This review focuses on potential targets for drug development to treat hair loss. The physiological processes underlying the promise of regenerative medicine to recreate new functional hair follicles in bald scalp are also examined. Expert opinion: The discovery of promising new targets may soon enable treatment options that modulate the hair cycle to preserve or extend the growth phase of the hair follicle. These new targets could also be leveraged to stimulate progenitor cells and morphogenic pathways to reactivate miniaturized follicles in bald scalp or to harness the potential of wound healing and embryogenic development as an emerging paradigm to generate new hair follicles in barren skin.