Search

Background: Minoxidil is a widely used over‐the‐counter topical treatment for hair loss. The response rate for topical minoxidil is relatively low. Minoxidil is a pro‐drug, converted to its active form, minoxidil sulfate, by SULT1A1 enzymes located in the scalp. Recently, a novel topical formula that increases the activity of SULT1A1 in hair follicles was reported. Aims: To evaluate any benefit of applying the SULT1A1 enzyme booster prior to daily 5% minoxidil treatment. Methods: Male androgenic alopecia patients were recruited to a randomized blinded placebo‐controlled study. Patients were randomized to receive 5% topical minoxidil plus the novel formula or minoxidil plus a sham adjuvant. Patient's hair growth was monitored using global photography over 60 days. Results: Twenty‐four males with androgenic alopecia (Norwood scale average 4.4, range 2–6) were randomized and completed the trial: 12 in the active arm and 12 in placebo. 75% of the subjects who used the SULT1A1 adjuvant with their daily minoxidil treatments for 60 days regrew hair versus 33% of those using the placebo adjuvant (p = 0.023). Conclusions: In a small cohort of androgenetic alopecia men, adding the SULT1A1 adjuvant to their daily minoxidil treatment regimen improved hair regrowth. [ABSTRACT FROM AUTHOR]

Alopecia areata (AA) is thought to be an autoimmune process. In other autoimmune diseases, the innate immune system and Toll‐like receptors (TLRs) can play a significant role. Expression of TLR7, TLR9 and associated inducible genes was evaluated by quantitative PCR in peripheral blood mononuclear cells (PBMCs) from 10 healthy individuals and 19 AA patients, categorized according to disease duration, activity and hair loss extent. Microdissected scalp biopsies from five patients and four controls were also assessed by quantitative PCR and immunohistology. TLR9 was significantly upregulated 2.37 fold in AA PBMCs. Notably, TLR9 was most significantly upregulated in patients with active AA, as shown by a positive hair pull test, compared to stable AA patients. In hair follicle bulbs from AA patients, IFNG and TLR7 exhibited statistically significant 3.85 and 2.70 fold increases in mRNA, respectively. Immunohistology revealed TLR7 present in lesional follicles, while TLR9 positive cells were primarily observed peri‐bulbar to AA affected hair follicles. The increased expression of TLR7 and TLR9 suggest components of the innate immune system may be active in AA pathogenesis. [ABSTRACT FROM AUTHOR]

Alopecia areata (AA) development is associated with both innate and adaptive immune cell activation, migration to peri- and intra-follicular regions, and hair follicle disruption. Both CD4+and CD8+lymphocytes are abundant in AA lesions; however, CD8+cytotoxic T lymphocytes are more likely to enter inside hair follicles, circumstantially suggesting that they have a significant role to play in AA development. Several rodent models recapitulate important features of the human autoimmune disease and demonstrate that CD8+cytotoxic T lymphocytes are fundamentally required for AA induction and perpetuation. However, the initiating events, the self-antigens involved, and the molecular signaling pathways, all need further exploration. Studying CD8+cytotoxic T lymphocytes and their fate decisions in AA development may reveal new and improved treatment approaches. [ABSTRACT FROM PUBLISHER]

We conducted a microarray study to discover gene expression patterns associated with a lack of melanogenesis in nonpigmented hair follicles (HF) by microarray. Pigmented and non-pigmented HFs were collected and micro-dissected into the hair bulb (HB) and the upper hair sheaths (HS) including the bulge region. In comparison to pigmented HS and HBs, nucleotide excision repair (NER) family genes ERCC1, ERCC2, ERCC3, ERCC4, ERCC5, ERCC6, XPA, NTPBP, HCNP, DDB2 and POLH exhibited statistically significantly lower expression in non- pigmented HS and HBs. Quantitative PCR verified microarray data and identified ERCC3 as highly differentially expressed. Immunohistochemistry confirmed ERCC3 expression in HF melanocytes. A reduction in ERCC3 by siRNA interference in human melanocytes in vitro reduced their tyrosinase production ability. Our results suggest that loss of NER gene function is associated with a loss of melanin production capacity. This may be due to reduced gene transcription and/or reduced DNA repair in melanocytes which may eventually lead to cell death. These results provide novel information with regard to melanogenesis and its regulation. [ABSTRACT FROM AUTHOR]

Folliculitis decalvans is a rare inflammatory scalp disorder. The present paper gives a practical approach to diagnosis and patient management and reviews possible pathogenetic factors and treatment options. Folliculitis decalvans is classified as primary neutrophilic cicatricial alopecia and predominantly occurs in middle-aged adults. Staphylococcus aureus and a deficient host immune response seem to play an important role in the development of this disfiguring scalp disease. Lesions occur mainly in the vertex and occipital area. Clinically, the lesions present with follicular pustules, lack of ostia, diffuse and perifollicular erythema, follicular tufting, and, oftentimes, hemorrhagic crusts and erosions. Histology displays a mainly neutrophilic inflammatory infiltrate in early lesions and additionally lymphocytes and plasma cells in advanced lesions. Treatment is focused on the eradication of S. aureus anti-inflammatory agents. [ABSTRACT FROM AUTHOR]

Lichen planopilaris is a chronic scarring alopecia characterized by follicular hyperkeratosis, perifollicular erythema, and loss of follicular orifices. The scalp lesions may be single or multiple and commonly involve the vertex and parietal area. The hair follicles at the margin of the alopecic patches reveal perifollicular erythema. Anagen hairs can be pulled out easily in active lesions. Associated cutaneous, nail, and mucous membrane lichen planus may be present. Commonly encountered symptoms and signs are increased hair shedding, itching, scaling, burning, and tenderness. Differentiation from other cicatricial alopecia can be performed through meticulous evaluation of the clinical, histopathologic, and immunohistopathologic findings. Treatment strategies depend on the disease activity and physician expertise. Although there are no definitive curative modalities, some new discoveries and conceptual advances continue to broaden our treatment options of this complex condition. [ABSTRACT FROM AUTHOR]

The activation of receptor complexes containing glycoprotein 130 (gp130) identifies the interleukin (IL)-6 cytokine family. We examined members of this family for their expression and activity in hair follicles. Quantitative polymerase chain reaction using mRNA derived from microdissected, anagen-stage human hair follicles and comparison to non-follicular skin epithelium revealed higher levels of IL-6 (15.5-fold) and oncostatin M (OSM, 3.4-fold) in hair follicles. In contrast, expression of all mRNAs coding for IL-6 cytokine family receptors was reduced. Immunohistology suggested expression of OSM, gp130, leukaemia inhibitory factor receptor (LIFr) and IL-11r in the hair follicle root sheaths and dermal papilla, while IL-11, IL-6r and OSMr were expressed in root sheaths alone. IL-6 was expressed in the dermal papilla while cardiotrophin-1 (CT-1) and LIF were not observed. OSM and to a lesser extent CT-1 exhibited a dose-dependent growth inhibition capacity on human hair follicles in vitro. OSM and CT-1 incubated with agarose beads and injected subcutaneously at 1 μg per mouse into telogen skin of 65-day-old mice revealed no capacity to induce anagen hair growth. In contrast, injection of 65-day-old mice in which anagen had been induced by hair plucking revealed a moderate hair growth inhibitory capacity for OSM, but no significant effect for CT-1. The data identify OSM as a modulator of hair follicle growth and suggest other family members may also have some degree of hair growth inhibitory effect. In principle, increased expression of some IL-6 cytokine family members in cutaneous inflammation might contribute to the promotion of hair loss. [ABSTRACT FROM AUTHOR]

Hair follicles produce hair fibers in a regular cycle. As part of their hair-producing role, hair follicles retain stem cells, promote cell growth and tissue invasion and induce angiogenesis. However, hair follicle function involves more than just hair fiber production. Hair follicles interact closely with the skin immune and neuroendocrine systems, supporting immunosurveilance against pathogens and aiding sensory perception. Hair follicles can also assist in wound healing and skin repigmentation. However, the unique properties of hair follicles can also be detrimental to skin health. Perhaps most significantly, hair follicles may contribute to the development of skin neoplasias. This article reviews the potential role of hair follicles in skin health. [ABSTRACT FROM AUTHOR]

The cicatricial alopecias encompass a diverse group of disorders characterized by permanent destruction of the hair follicle and irreversible hair loss. Destruction of the hair follicle can result from primary, folliculocentric disease or as a secondary result. This article focuses on the former, or primary cicatricial alopecias. The cause and pathogenesis of many of these disorders are largely unknown. Although unique clinicopathologic features allow for accurate diagnosis in some cases, diagnostic certainty is often elusive and reflects the limits of present understanding. Classification of the primary cicatricial alopecias on the basis of pathology provides a diagnostic and investigational framework and, it is hoped, will facilitate future enlightenment. Details of classification, etiopathogenesis, clinicopathologic features, differential diagnosis, and practical management of the primary cicatricial alopecias will be discussed. Learning objectives: Upon completion of this learning activity, participants should be familiar with the following aspects of the primary cicatricial alopecias: (1) the new, consensus-issued classification scheme, (2) current understanding about etiopathogenesis, (3) salient clinicopathologic features, (4) differential diagnosis, and (5) therapeutic management. [Copyright &y& Elsevier]

The immune privilege (IP) of hair follicles (HFs) has been well established in previous studies. However, whether cultured HF cells still exhibit IP properties, the individual factors involved in this process, and the detailed mechanisms that drive and maintain IP, are largely unidentified. We found preferential expression of IP-associated genes in cultured HF dermal papilla and dermal sheath cup cells (DSCCs) compared with non-follicular fibroblasts (FBs) at passage 4, suggesting a potential for functional IP. Notably, programmed cell death 1 ligand 1 (PD-L1) was significantly upregulated in DSCCs and dermal papilla cells relative to FBs. IFNγ secretion from peripheral blood mononuclear cells (PBMCs) co-cultured with histoincompatible DSCCs was significantly lower than with FB and higher percentages of early apoptotic, Annexin V+ cells were observed in PBMC co-cultured with DSCCs. Knockdown of PD-L1 translation by silencing interfering RNA in DSCCs enabled increased IFNγ secretion by PBMCs, whereas transfection of pCMV6-XL4/hPD-L1 in FB significantly reduced IFNγ secretion and increased apoptosis in co-cultured PBMCs. We also found that apoptosis in allogeneic T cells induced by DSCCs was largely dependent on the mitochondrial pathway. Our study suggests IP properties are exhibited in cultured DSCCs in part through expression of negative co-signaling molecule PD-L1. [ABSTRACT FROM AUTHOR]

Immune privilege (IP) is believed to exist in the anagen hair follicle (HF). Studies have shown that downregulation of major histocompatibility complex Class I occurs and immunosuppressive factors are expressed in the HF bulb and bulge. However, demonstration and quantification of functional IP in HF cells are required. We examined the middle (sheath) and lower (bulb) portions of the human HF using quantitative real-time RT-PCR (qPCR), immunohistology, ELISA, in vitro coculture with peripheral blood mononuclear cells (PBMCs), and flow cytometry. We found that HF cells, relative to non-follicular epidermal cells, failed to promote allogeneic PBMC proliferation and CD4+ and CD8+ IFNγ production. By qPCR, we found significant downregulation of Class I and Class II HLA alleles in both the bulb and sheath, and upregulation of multiple immunoregulatory genes. It is noteworthy that somatostatin (SST) was significantly upregulated relative to epidermis. By immunohistochemistry, SST was most strongly expressed in the HF outer root sheath, and, by ELISA, cultured sheath cells secreted SST. PBMCs, cultured with stimulatory allogeneic epidermal cells and SST, secreted significantly less IFNγ than controls. Addition of SST antagonists to PBMCs cocultured with allogeneic HF cells increased IFNγ secretion. The data identify SST as a secretory factor potentially contributing to the HF IP repertoire. [ABSTRACT FROM AUTHOR]

Alopecia areata is regarded as a tissue-restricted autoimmune disease of hair follicles in which follicular activity is arrested because of the continued activity of lymphocytic infiltrates. Actual loss of hair follicles does not occur, even in hairless lesions. A variety of immunomodulating therapies, including contact sensitizers and immunomodulators, are part of the usual armamentarium for this disorder. None of these treatments have been consistent in their efficacy, and many have untoward side effects. Nevertheless, their uses in valid animal models provide a tool to dissect out molecular mechanisms of therapeutic effects. For several decades, both mechlorethamine (for the treatment of cutaneous T cell lymphoma) and anthralin (for the treatment of psoriasis) have been used successfully. When these therapies were tested in rat and mouse alopecia areata models, we found anthralin and mechlorethamine to be the most effective topical modalities, respectively. The underlying cellular mechanisms may act through targeting infiltrative lymphocytes, and the molecular mechanisms may involve specific cytokine expression changes. These visible, accessible, and unilaterally treated animal model systems are ideal for studying novel alopecia areata therapies, particularly in terms of their in vivo molecular mechanisms of action. [ABSTRACT FROM AUTHOR]

Although many therapeutic modalities have been tested on alopecia areata, patient outcomes have been disappointing. Use of animal models would help to develop more efficient therapies as well as understanding therapeutic mechanisms. We have demonstrated that 0.1% topical anthralin ointment is 100% effective in restoring follicular activity in Dundee experimental balding rats. This is the most promising topical treatment for Dundee experimental balding rats among the therapeutic agents tested on this model. Various cytokines have been shown to be associated with the pathogenesis of alopecia areata. To test whether any of these cytokines might be modulated by anthralin, an RNase protection assay and the real-time polymerase chain reaction were performed to compare their expression between anthralin-treated and control skins. These experiments showed that expression of tumor necrosis factor-α and interferon-γ was inhibited by anthralin, whereas expression of interleukin-1α/β and their receptor antagonist, interleukin-1Ra, and interleukin-10 was stimulated by anthralin. In addition, using an antibody-based multi-immunoblotting technique, we found that certain signaling regulatory proteins were modulated by anthralin. Their potential roles in reversing the autoimmune-arrested follicular activity in Dundee experimental balding rats are discussed. [ABSTRACT FROM AUTHOR]

Evaluates the regenerative capacity of transversely sectioned hair follicle in athymic nude mice. Occipital areas of patients undergoing hair transplantation; Histologic features of hair follicle; Causes of low successful regeneration rate.