Low level laser therapy and hair regrowth: an evidence-based review

Deciphering the molecular mechanisms of stem cell dynamics in hair follicle regeneration

Hair follicles, which are connected to sebaceous glands in the skin, undergo cyclic periods of regeneration, degeneration, and rest throughout adult life in mammals. The crucial function of hair follicle stem cells is to maintain these hair growth cycles. Another vital aspect is the activity of melanocyte stem cells, which differentiate into melanin-producing melanocytes, contributing to skin and hair pigmentation. Sebaceous gland stem cells also have a pivotal role in maintaining the skin barrier by regenerating mature sebocytes. These stem cells are maintained in a specialized microenvironment or niche and are regulated by internal and external signals, determining their dynamic behaviors in homeostasis and hair follicle regeneration. The activity of these stem cells is tightly controlled by various factors secreted by the niche components around the hair follicles, as well as immune-mediated damage signals, aging, metabolic status, and stress. In this study, we review these diverse stem cell regulatory and related molecular mechanisms of hair regeneration and disease conditions. Molecular insights would provide new perspectives on the disease mechanisms as well as hair and skin disorder treatment.

Comparative efficacy of 2% minoxidil alone against combination of 2% minoxidil and low-level laser therapy in female pattern hair loss-A randomized controlled trial in Chinese females

OBJECTIVES

To investigate the effectiveness and safety of combination of 655 nm low level laser helmet device with topical 2 % minoxidil solution at FPHL in Chinese population.

MATERIALS AND METHODS

Randomized, parallel, controlled, single-blind clinical trial was conducted. FPHL subjects were randomly allocated into 2 % minoxidil group and combination group. The 2 % minoxidil group received 1 ml topical 2 % minoxidil solution twice daily for 24 weeks. The combination group received 1 ml topical 2 % minoxidil solution twice daily together with 20 min 655 nm low-level laser helmet once every other day for 24 weeks. Hair parameters in two scalp areas including midscalp and vertex were evaluated at baseline, 12th week and 24th week.

RESULTS

In midscalp area, the combination group showed a lower increase in intermediate hair percentage than 2 % minoxidil group, which was statistically significant. Besides, the combination group had statistically significant increase than 2 % minoxidil group in mean hair diameter. Reported relative adverse events included slightly hair loss (27.8 %), desquamation (19.0 %), pruritus (15.2 %), seborrhea (2.5 %) and hypertrichosis (2.5 %).

CONCLUSION

In our trial, LLLT was demonstrated as a useful supplementary treatment for FPHL and the combination with 2 % minoxidil accomplished better improvement in intermediate hair enlargement and hair diameter of midscalp for FPHL.

Surgical Management for Hair Restoration: A Review of Contemporary Techniques

BACKGROUND

Hair loss can cause psychological distress for patients, regardless of the etiology or extent of the defect. Many conservative and pharmacological approaches are successful in management, but refractory or severe cases often mandate surgical treatment. Surgical techniques have been refined over the course of a century, and we aim to review the most contemporary strategies.

METHODS

A review of the literature was performed using the databases PubMed, Web of Science, and Embase, in May 2020. Articles were included if they discussed techniques used within the past 10 years, in search of more contemporary strategies and the most widely used approaches.

RESULTS

The use of local flaps, scalp reduction surgery, and hair transplantation techniques are all used for various indications. Modern hair transplantation can be further divided into follicular unit excision and follicular unit transplantation, each with its own advantages. Local flaps are most often used for post-traumatic and reconstructive indication, while hair transplantation can be used for smaller cosmetic lesions or in combination with a variety of other reconstructive techniques.

CONCLUSION

Hair loss continues to be a challenging pathology for both patients and physicians, regardless of etiology. When conservative treatment is inadequate, there exist multiple surgical techniques that can feasibly restore hair, though the exact degree of success may vary between patients. The proper technique is dependent upon etiology, patient specific factors, as well as surgeon experience and comfort.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Photobiomodulation and alopecia: a crowdsourced survey study on patient preferences

Photobiomodulation is a treatment option for hair loss and is currently FDA cleared for androgenetic alopecia. There are a variety of photobiomodulation devices intended for at-home patient use. However, data examining user preferences is lacking. A social media-based, online survey study was completed to understand patient preferences when selecting a photobiomodulation device. Secondary outcomes examined patient experience with the device. Sixty participants responded to the 21-question survey. The majority of participants had never used a photobiomodulation device (n = 50; 86.2%). Most respondents (n = 40; 67.8%) felt the efficacy of the device was the most important aspect to consider when selecting a photobiomodulation device. Additionally, a majority of participants thought 15 (n = 22; 37.3%) or 20 minutes (n = 17; 28.8%) would be a reasonable treatment duration and would prefer a hand-free device (n = 51; 86.4%). Of the eight participants who had used a photobiomodulation device, only one was dissatisfied with the device and discontinued treatment.

Nanotechnology-based techniques for hair follicle regeneration

The hair follicle (HF) is a multicellular complex structure of the skin that contains a reservoir of multipotent stem cells. Traditional hair repair methods such as drug therapies, hair transplantation, and stem cell therapy have limitations. Advances in nanotechnology offer new approaches for HF regeneration, including controlled drug release and HF-specific targeting. Until recently, embryogenesis was thought to be the only mechanism for forming hair follicles. However, in recent years, the phenomenon of wound-induced hair neogenesis (WIHN) or de novo HF regeneration has gained attention as it can occur under certain conditions in wound beds. This review covers HF-specific targeting strategies, with particular emphasis on currently used nanotechnology-based strategies for both hair loss-related diseases and HF regeneration. HF regeneration is discussed in several modalities: modulation of the hair cycle, stimulation of progenitor cells and signaling pathways, tissue engineering, WIHN, and gene therapy. The HF has been identified as an ideal target for nanotechnology-based strategies for hair regeneration. However, some regulatory challenges may delay the development of HF regeneration nanotechnology based-strategies, which will be lastly discussed.

Bioactive Compound-Loaded Nanocarriers for Hair Growth Promotion: Current Status and Future Perspectives

Hair loss (alopecia) has a multitude of causes, and the problem is still poorly defined. For curing alopecia, therapies are available in both natural and synthetic forms; however, natural remedies are gaining popularity due to the multiple effects of complex phytoconstituents on the scalp with fewer side effects. Evidence-based hair growth promotion by some plants has been reported for both traditional and advanced treatment approaches. Nanoarchitectonics may have the ability to evolve in the field of hair- and scalp-altering products and treatments, giving new qualities to hair that can be an effective protective layer or a technique to recover lost hair. This review will provide insights into several plant and herbal formulations that have been reported for the prevention of hair loss and stimulation of new hair growth. This review also focuses on the molecular mechanisms of hair growth/loss, several isolated phytoconstituents with hair growth-promoting properties, patents, in vivo evaluation of hair growth-promoting activity, and recent nanoarchitectonic technologies that have been explored for hair growth.

What's New in Therapy for Male Androgenetic Alopecia?

Male androgenetic alopecia is a common condition and represents a major concern for patients who experience this condition. While there are different treatments to stop hair loss and improve hair density, the 5-alpha reductase inhibitors have demonstrated to be effective in improving androgenetic alopecia in men and can maintain a positive response for many years. Oral finasteride 1 mg is a US FDA-approved option, but dutasteride 0.5 mg has been proven to induce better responses, especially in the frontal area. Both have been shown to be safe in clinical trials but there is widespread concern about sexual adverse effects among patients. The use of topical finasteride has increased during the last few years as a useful option to avoid systemic therapy. The efficacy of topical finasteride 0.25% daily has been demonstrated in clinical trials, with a less marked decrease in serum dihydrotestosterone levels than with oral intake. Mesotherapy with dutasteride has also become more widespread recently, although evidence of its effectiveness is limited to retrospective studies in real clinical practice. The use of oral minoxidil in androgenetic alopecia has not been approved by the FDA, however several clinical studies have shown that it is an effective treatment option. The initial dose recommended to treat male hair loss is 2.5 mg daily, although the dose is frequently increased to 5 mg daily. The main adverse effect of oral minoxidil is hypertrichosis, followed by dizziness or lower limb edema, which are much less common. Platelet-rich plasma is a non-pharmacological option to treat male androgenetic alopecia, with some clinical trials demonstrating an improvement in hair count after several months. Among the published studies, the main limitation to compare its efficacy is the heterogeneity of the procedure. The most frequent regimens propose treatment every 4 weeks for 3 months initially to assess the individual response. Another treatment alternative is the use of light devices with wavelengths of between 630 and 660 nm, known as low-level laser therapy. These devices can be used at home every day for 15-30 min. Their efficacy has been shown in a limited number of clinical trials; however, there is a lack of evidence about the efficacy of these devices compared with other medical options or as a complementary therapy in hair loss. The pipeline of potential new treatments for male androgenetic alopecia is strong. Pyrilutamide and GT20029 are being studied as topical antagonists of the androgen receptor, while cetirizine is another topical option with some initial promising results. Furthermore, according to isolated studies with heterogeneous treatment schemes, the use of botulinum toxin in the scalp might improve androgenetic alopecia, and lastly, scalp threading might increase the total hair count as growth factors are released during implantation.

Advances in microneedles research based on promoting hair regrowth

Alopecia is the most common and difficult-to-treat hair disorder. It usually brings a significant psychological burden to the patients. With the growing popularity of alopecia, the study of alopecia has gained more attention. Currently, only minoxidil and finasteride have been approved by the FDA for the treatment of alopecia, but the efficacy has always been unsatisfactory. As a new form of transdermal drug delivery, microneedles have been widely used in the treatment of alopecia and have proven to be effective. Microneedles delivery can improve the efficiency of local drug delivery and patients' compliance, which can achieve better therapeutic effects on hair-related diseases. Therefore, microneedles have gained much attention in the field of alopecia and hair regrowth promotion in recent years. This review summarizes the last decade of research on the microneedles delivery design for the treatment of alopecia or promotion of hair regrowth and provides a comprehensive evaluation of this field.

Enhanced hair growth effects through low-level vortex beams radiation: An experimental animal study

Photobiomodulation therapy (PBMT) is a non-invasive and pain-less treatment for hair loss. Researches on PBMT rarely considered the impact of different light structures. In this study, we irradiated shaven rats with both 650 nm, m = 32 vortex beams and ordinary Gaussian beams. The laser treatment was performed at 24-hour intervals for 20 days. The energy density was set to 4.25 J/cm² . The results indicated that low-level vortex beam irradiation led to better stimulation of hair growth than the Gaussian beams, which might be related to deeper penetration. The underlying biological mechanisms are discussed in terms of the activation of Wnt/β-catenin/sonic hedgehog pathway. Our results suggest that low-level vortex beam irradiation is advantageous to the treatment of hair loss because it is technically feasible, convenient and effective.

Alopecia in children undergoing chemotherapy, radiation, and hematopoietic stem cell transplantation: Scoping review and approach to management

Alopecia is a common sequela in children undergoing chemotherapy, radiation, and hematopoietic stem cell transplantation. In most cases, this is a transient state in which full hair regrowth eventually occurs, but permanent or persistent alopecia, defined as the presence of incomplete hair regrowth more than 6 months after cessation of treatment, is possible and can be psychologically distressing. We sought to characterize the risk factors that can lead to permanent alopecia following the aforementioned treatments in pediatric populations, as well as diagnostic and treatment options that may be considered, as part of a scoping review of the literature. A general algorithm for approaching these patients was developed based on our findings.

Low Level Laser versus Platelet-rich Plasma in Treatment of Alopecia Areata: A Randomized Controlled Intra-patient Comparative Study

Abstract                                                                                                           Background: Non-scarring alopecia areata (AA) is a disease that is mediated through autoimmunity. Recently, autologous platelet-rich plasma (PRP) and photobiomodulation (PBM), commonly known as low-level laser (or light, LLLT) have been suggested to provide a valuable role in stimulating the growth of hair follicles (HF) Aim: Compare between the significance and wellbeing of PRP and LLLT in the management of AA. Patients & methodology: Thirty patients, each having three patches of AA participated in the study. Patches were assigned randomly to have one of the two treatments: PRP or LLLT. The third patch served as a control and received placebo treatment. PRP was done once weekly whereas LLLT was done 3 sessions per week for a maximum of 6 weeks. Patients were followed up at one month and three months. The thickness and density of hair were evaluated by the folliscope. Results: A noteworthy higher improvement was detected in the thickness and the density of hair in the PRP treated patches as evaluated by the folliscope and patients satisfaction. The obtained outcomes were sustained during the 12 week follow-up period in most of patients. Conclusion: PRP and LLLT could be considered as efficacious alternatives for the treatments of  AA with the least morbidity in addition to a little cost profit ratio. KEYWORDS: Alopecia areata, platelet-rich plasma, folliscope, photobiomodulation, low level laser therapy.  

Head and Neck Restoration in Scar Alopecia: Hair Transplantation in Scalp, Eyebrows, Beard and Mustache

BACKGROUND

Surgical management of hair loss has become an increasingly challenging procedure, when dealing with scar alopecia. We investigated the efficacy of hair transplantation in patients with head and neck scar alopecia.

METHODS

From 2016 to 2018 in Shiraz, Iran, all patients with scar alopecia in head and neck were evaluated for efficacy of follicular unit extraction (FUE), follicular unit transplantation (FUT) or a combination of two methods from donor sites in scalp and beard various hair-grafts were compared.

RESULTS

Fifty-six patients were enrolled. Most of them were between 31 and 40 yr old (48.3%) and male (71.4%). Trauma, burn, surgical excision of adjacent skin, radiotherapy and leishmaniasis were the registered causes. Scars were visible in scalp (39.3%), beard (28.6%), eyebrow (21.4%), and moustache (10.7%) regions. FUE (87.5%), FUT (10.7%) and a combination (1.8%) were the used methods. One-hair-grafts were used in eyebrows (100%), moustache (100%), beard (88%) and scalp (7.9%), while 2-hair-grafts in beard (6%) and scalp (47.4%) and 3-haired grafts in beard (6%) and scalp (44.7%) transplantations.

CONCLUSION

In head and neck scar alopecia, hair transplantation was selected based on type and depth of scar. FUE was targeted when huge grafts were not needed, including beard, moustache, and eyebrow, while FIT was used when extensive scars were present in scalp. One-hair-grafts were mostly applied for eyebrow, moustache and beard, 2-hair- and 3-hair- grafts for beard and scalp transplantation. These findings can be added to the literature when FUE, FIT, or their combination are targeted in hair restoration of scar alopecia in head and neck.

Dosimetry and Clinical Efficacy of Transcranial Photobiomodulation for Major Depression Disorder: Could they Guide Dosimetry for Alzheimer's Disease?

BACKGROUND

Major depressive disorder (MDD) is prevalent and has significant impact on individuals and society. Cognitive symptoms are frequent in MDD and insufficiently treated by antidepressant medications. Transcranial photobiomodulation (t-PBM) is a novel device therapy which shows promise as an antidepressant and pro-cognitive treatment. To date, despite the encouraging results, the optimal stimulation parameters of t-PBM to treat MDD are not established, and clinical studies are very heterogeneous in terms of these parameters. While the literature provides guidance on the appropriate fluence to achieve therapeutic results, little is known on the other parameters.

OBJECTIVE

To evaluate the relationship between different parameters and the antidepressant effect of t-PBM.

METHODS

We reviewed clinical studies on MDD and on depressive symptoms comorbid with other diseases. We calculated the standardized effect size of the change in symptoms severity before and after t-PBM and we performed a descriptive analysis of the reviewed papers.

RESULTS

The greatest effect sizes for the antidepressant effect were found in studies using pulse-wave t-PBM with high peak irradiance (but low average irradiance) over large skin surface. One well-designed and sufficiently powered, double-blind, sham-controlled trial indicated that t-PBM with low irradiance over a small skin surface is ineffective to treat depression.

CONCLUSION

The use of t-PBM for Alzheimer's disease and for dementia is still at its inception; these dosimetry lessons from the use of t-PBM for depression might serve as guidance.

Triboelectric Nanogenerators for Therapeutic Electrical Stimulation

Current solutions developed for the purpose of in and on body (IOB) electrical stimulation (ES) lack autonomous qualities necessary for comfortable, practical, and self-dependent use. Consequently, recent focus has been placed on developing self-powered IOB therapeutic devices capable of generating therapeutic ES for human use. With the recent invention of the triboelectric nanogenerator (TENG), harnessing passive human biomechanical energy to develop self-powered systems has allowed for the introduction of novel therapeutic ES solutions. TENGs are especially effective at providing ES for IOB therapeutic systems given their bioconformability, low cost, simple manufacturability, and self-powering capabilities. Due to the key role of naturally induced electrical signals in many physiological functions, TENG-induced ES holds promise to provide a novel paradigm in therapeutic interventions. The aim here is to detail research on IOB TENG devices applied for ES-based therapy in the fields of regenerative medicine, neurology, rehabilitation, and pharmaceutical engineering. Furthermore, considering TENG-produced ES can be measured for sensing applications, this technology is paving the way to provide a fully autonomous personalized healthcare system, capable of IOB energy generation, sensing, and therapeutic intervention. Considering these grounds, it seems highly relevant to review TENG-ES research and applications, as they could constitute the foundation and future of personalized healthcare.

Photobiomodulation therapy for hair regeneration: A synergetic activation of β-CATENIN in hair follicle stem cells by ROS and paracrine WNTs

Photobiomodulation therapy (PBMT) has shown encouraging results in the treatment of hair loss. However, the mechanism by which PBMT controls cell behavior to coordinate hair cycle is unclear. Here, PBMT is found to drive quiescent hair follicle stem cell (HFSC) activation and alleviate hair follicle atrophy. Mechanistically, PBMT triggers a new hair cycle by upregulating β-CATENIN expression in HFSCs. Loss of β-Catenin (Ctnnb1) in HFSCs blocked PBMT-induced hair regeneration. Additionally, we show PBMT-induced reactive oxygen species (ROS) activate the PI3K/AKT/GSK-3β signaling pathway to inhibit proteasome degradation of β-CATENIN in HFSCs. Furthermore, PBMT promotes the expression and secretion of WNTs in skin-derived precursors (SKPs) to further activate the β-CATENIN signal in HFSCs. By contrast, eliminating ROS or inhibiting WNT secretion attenuates the activation of HFSCs triggered by PBMT. Collectively, our work suggests that PBMT promotes hair regeneration through synergetic activation of β-CATENIN in HFSCs by ROS and paracrine WNTs by SKPs.

Photobiomodulation: The Clinical Applications of Low-Level Light Therapy

BACKGROUND

Low-level light therapy (LLLT) is a recent addition to the pantheon of light-based therapeutic interventions. The absorption of red/near-infrared light energy, a process termed "photobiomodulation," enhances mitochondrial ATP production, cell signaling, and growth factor synthesis, and attenuates oxidative stress. Photobiomodulation is now highly commercialized with devices marketed directly to the consumer. In the gray area between the commercial and therapeutic sectors, harnessing the clinical potential in reproducible and scientifically measurable ways remains challenging.

OBJECTIVES

The aim of this article was to summarize the clinical evidence for photobiomodulation and discuss the regulatory framework for this therapy.

METHODS

A review of the clinical literature pertaining to the use of LLLT for skin rejuvenation (facial rhytids and dyschromias), acne vulgaris, wound healing, body contouring, and androgenic alopecia was performed.

RESULTS

A reasonable body of clinical trial evidence exists to support the role of low-energy red/near-infrared light as a safe and effective method of skin rejuvenation, treatment of acne vulgaris and alopecia, and, especially, body contouring. Methodologic flaws, small patient cohorts, and industry funding mean there is ample scope to improve the quality of evidence. It remains unclear if light-emitting diode sources induce physiologic effects of compararable nature and magnitude to those of the laser-based systems used in most of the higher-quality studies.

CONCLUSIONS

LLLT is here to stay. However, its ubiquity and commercial success have outpaced empirical approaches on which solid clinical evidence is established. Thus, the challenge is to prove its therapeutic utility in retrospect. Well-designed, adequately powered, independent clinical trials will help us answer some of the unresolved questions and enable the potential of this therapy to be realized.

Results of low-level laser therapy in the treatment of hair growth: An Egyptian experience

Recently, low level laser therapy was evaluated as an effective stimulating hair growth. Hair loss is the most common complaint in dermatology (specially females). It causes a significant psychosocial distress and decreased quality of life in affected patients and exists in different types, but the most common types are androgenetic alopecia and telogen effluvium (TE). Although there are many treatments with highest levels of medical evidence, but patients who exhibit intolerance or poor response to these treatments need additional treatment modalities. To evaluate the efficacy and safety low level laser therapy for female pattern hair loss (FPHL) and TE. A prospective interventional study included 20 female patients, 13 were diagnosed as FPHL, and 7 were diagnosed TE. Patients received two sessions per week with Hair Growth System (TOPHAT655) a bicycle-helmet type device. Treatment session of 20 minutes for 16 successive weeks (total of 32 treatments) with follow-up. Patients were evaluated by software-analyzed trichoscopic images, as the primary endpoint was the percent increase in hair counts from baseline to post-treatment. Global photography and patient satisfaction were determined as a secondary end point. Twenty patients completed the study (13 FPHL, 7 TE). FPHL patients baseline hair counts were 222.3 ± 33.5 (N = 13), in TE patients baseline hair counts were 271.2 ± 39.0 (N = 7). Post-treatment hair counts were 255.3 ± 30.4 (N = 13) In FPHL patients (P = .007), and 294.2 ± 38.1 (N = 7) in TE patients (P = .143). Low level laser therapy of the scalp at 655 nm significantly improved hair counts in FPHL, and there is no significance difference in TE patients with no serious adverse events. Additional studies should be considered to determine the long-term effects of low-level laser therapy treatment on hair growth and maintenance, and to optimize laser modality.

Evaluation of Efficacy of Low-Level Laser Therapy

Introduction: Given the inconsistencies in the literature regarding laser performance in non-surgical treatments, this study investigated the available literature to determine the advantages and disadvantages of low-power lasers in treating non-surgical complications and diseases. Methods: Authentic information from articles was extracted and evaluated to assess low-power laser performance for non-surgical treatments. A systematic search of studies on low-level laser therapy (LLLT) for non-surgical treatments was conducted mainly in PubMed and google scholar articles. Results: Four categories of diseases, including brain-related diseases, skin-related diseases, cancers, and bone-related disorders, which were treated by LLLT were identified and introduced. The various types of LLLT regarding the studied diseases were discussed. Conclusion: Positive aspects of LLLT versus a few disadvantages of its application imply more investigation to find better and efficient new methods.

A review of the treatment of male pattern hair loss

Introduction: Androgenetic alopecia is a common hair loss disorder affecting up to 80% of males by the age of 80. It is characterized by androgen related progressive thinning of hair in a defined pattern. It results in diminished self-esteem, reduced confidence and distress in affected men, irrespective of age or stage of baldness. An effective treatment for hair baldness is needed.Areas covered: In androgenetic alopecia, hair follicles undergo progressive miniaturization. Genetic factors and androgens are key role-players in disease pathogenesis. Herein the authors review the pharmacologic treatment of androgenetic alopecia, which involves 5 alpha reductase inhibitors, minoxidil and prostaglandins. Non-pharmacologic approaches are also explored.Expert opinion: Androgenetic alopecia progresses over time and although the current available medical treatments like finasteride and minoxidil are effective in arresting the progression of the disease, they allow only partial regrowth of hair at its best. Early treatment achieves a more optimal outcome. Non-pharmacologic treatments like PRP can be considered in patients refractory to medical treatment.Abbreviations: MPHL: male pattern hair loss; AGA: androgenetic alopecia; DHT: dihydrotestosterone; 5AR: 5-alpha-reductase; VEGF: vascular endothelial growth factor; PG's: prostaglandins (PG's); PGD2R: prostaglandin D2 receptor; VPA: valproic aid; SR: Serenoa Repens; PRP: platelet-rich plasma; PDGF: platelet derived growth factor; TGF: transforming growth factor; ERK: extracellular signal-regulated kinase; PKB: protein kinase B; LLLT: low-level laser therapy; ROS: reactive oxygen species; RCT: randomized control trial; SFRP1: secreted frizzled related protein 1; DP: dermal papilla; PDE5: phosphodiesterase 5.

The Effect of Photobiomodulation Therapy on the Differentiation, Proliferation, and Migration of the Mesenchymal Stem Cell: A Review

Introduction: The purpose of this study is to investigate the effect of a low-power laser on the proliferation, migration, differentiation of different types of mesenchymal stem cells (MSCs) in different studies. Methods: The relevant articles that were published from 2004 to 2019 were collected from the sources of PubMed, Scopus, and only the articles specifically examining the effect of a lowpower laser on the proliferation, differentiation, and migration of the MSCs were investigated. Results: After reviewing the literature, only 42 articles were found relevant. Generally, most of the studies demonstrated that different laser parameters increased the proliferation, migration, and differentiation of the MSCs, except the results of two studies which were contradictory. In fact, changing the parameters of a low-power laser would affect the results. On the other hand, the source of the stem cells was reported as a key factor. In addition, the combination of lasers with other therapeutic approaches was found to be more effective. Conclusion: The different parameters of lasers has been found to be effective in the proliferation, differentiation, and migration of the MSCs and in general, a low-power laser has a positive effect on the MSCs, helping to improve different disease models.

Under the spotlight: mechanisms of photobiomodulation concentrating on blue and green light

Photobiomodulation (PBM) describes the application of light at wavelengths ranging from 400-1100 nm to promote tissue healing, reduce inflammation and promote analgesia. Traditionally, red and near-infra red (NIR) light have been used therapeutically, however recent studies indicate that other wavelengths within the visible spectrum could prove beneficial including blue and green light. This review aims to evaluate the literature surrounding the potential therapeutic effects of PBM with particular emphasis on the effects of blue and green light. In particular focus is on the possible primary and secondary molecular mechanisms of PBM and also evaluation of the potential effective parameters for application both in vitro and in vivo. Studies have reported that PBM affects an array of molecular targets, including chromophores such as signalling molecules containing flavins and porphyrins as well as components of the electron transport chain. However, secondary mechanisms tend to converge on pathways induced by increases in reactive oxygen species (ROS) production. Systematic evaluation of the literature indicated 72% of publications reported beneficial effects of blue light and 75% reported therapeutic effects of green light. However, of the publications evaluating the effects of green light, reporting of treatment parameters was uneven with 41% failing to report irradiance (mW cm-2) and 44% failing to report radiant exposure (J cm-2). This review highlights the potential of PBM to exert broad effects on a range of different chromophores within the body, dependent upon the wavelength of light applied. Emphasis still remains on the need to report exposure and treatment parameters, as this will enable direct comparison between different studies and hence enable the determination of the full potential of PBM.

Several biological benefits of the low color temperature light-emitting diodes based normal indoor lighting source

Currently, light pollution has become a nonnegligible issue in our daily life. Artificial light sources with high color temperature were deem to be the major pollution source, which could induce several adverse effects on human’s health. In our previous research, we have firstly developed an artificial indoor light with low color temperature (1900 K). However, the biological effects of this artificial light on human’s health are unclear. Here, four artificial lights (1900 K, 3000 K, 4000 K and 6600 K) were used to evaluate some biological changes in both human (in total 152 person-times) and murine models. Compared with other three high color temperature artificial lights, our lights (1900 K) presented a positive effect on promoting the secreting of melatonin and glutamate, protecting human’s eyes, accelerating would healing and hair regeneration. These systematical studies indicated that the proposed low color temperature (1900 K) light could provide several significant benefits in human’s daily life.

The psychological and aesthetic impact of age-related hair changes in females

BACKGROUND

While dermatologists focus on practices to promote anti-aging, thinning hair that frames a more rejuvenated face can affect age perception and cosmesis.

OBJECTIVES

To characterize the effects of age-related hair changes on age determination and perceived attractiveness.

METHODS

A search was conducted for articles on intrinsic and extrinsic aging as it relates to hair. Key studies on the hair aging process and its effects on self-perception, confidence, and anti-aging were reviewed.

RESULTS

According to several studies, hair density peaks about 27 years of age or earlier and then decreases from the mid-thirties onward. This serves as an opportunity to prevent or treat hair loss in a similar way we treat aging skin. Without optimizing appearance of hair, overall cosmesis to foster self-perception can be curtailed despite multiple efforts to rejuvenate and restore the aging face.

CONCLUSION

The discrepancy between rejuvenated faces and thinner appearing hair that frames the face highlights the importance of a holistic approach to the anti-aging consultation. To more comprehensively address the aesthetic patient, we need to promote awareness of the onset of these hair changes in order to incorporate prevention and therapeutic strategies to preserve hair to complement overall appearance.

Quantitative proteomic analysis of dermal papilla from male androgenetic alopecia comparing before and after treatment with low-level laser therapy

BACKGROUND

Currently, low-level laser therapy (LLLT) has been approved as a new treatment for androgenetic alopecia (AGA). However, it has not been elucidated how LLLT promotes hair growth in vivo.

OBJECTIVES

To investigate the change in protein expression from dermal papilla (DP) tissues in male AGA patients after LLLT treatment using liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis.

METHODS

This is an open-label, prospective, single-arm study obtained punch scalp biopsy specimens from patients with AGA before and after LLLT treatment. Each subject was self-treated with helmet type of LLLT (655 nm, 5 mW) device at home for 25 minutes per treatment every other day for 24 weeks. LC-MS/MS analysis based on the dimethyl labeling strategy for protein quantification was used to identify proteins expressed in DP tissues from AGA patients.

RESULTS

Proteomic analysis revealed 11 statistically significant up-regulated and 2 down-regulated proteins in LLLT treated DP compared with baseline (P < 0.05). A bioinformatic analysis signifies that these proteins are involved in several biological processes such as regulation of cellular transcription, protein biosynthesis, cell energy, lipid homeostasis, extracellular matrix (ECM), ECM structural constituent, cell-cell/cell-matrix adhesion as well as angiogenesis. ATP-binding cassette sub-family G member, a transporter involved in cellular lipid homeostasis, was the most up-regulated protein. Additionally, LLLT increased the main ECM proteins in DP which results in a bigger volume of DP and a clinical improvement of hair diameter in AGA patients.

CONCLUSION

We identified the proteome set of DP proteins of male patients with AGA treated with LLLT which implicates the role of LLLT in promoting hair growth and reversing of miniaturization process of AGA by enhancing DP cell function. Our results strongly support the benefit of LLLT in the treatment of AGA. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Acquired Resilience: An Evolved System of Tissue Protection in Mammals

This review brings together observations on the stress-induced regulation of resilience mechanisms in body tissues. It is argued that the stresses that induce tissue resilience in mammals arise from everyday sources: sunlight, food, lack of food, hypoxia and physical stresses. At low levels, these stresses induce an organised protective response in probably all tissues; and, at some higher level, cause tissue destruction. This pattern of response to stress is well known to toxicologists, who have termed it hormesis. The phenotypes of resilience are diverse and reports of stress-induced resilience are to be found in journals of neuroscience, sports medicine, cancer, healthy ageing, dementia, parkinsonism, ophthalmology and more. This diversity makes the proposing of a general concept of induced resilience a significant task, which this review attempts. We suggest that a system of stress-induced tissue resilience has evolved to enhance the survival of animals. By analogy with acquired immunity, we term this system 'acquired resilience'. Evidence is reviewed that acquired resilience, like acquired immunity, fades with age. This fading is, we suggest, a major component of ageing. Understanding of acquired resilience may, we argue, open pathways for the maintenance of good health in the later decades of human life.

Prescribing Habits for Androgenic Alopecia Among Dermatologists in Spain in 2017: A Cross-Sectional Study

BACKGROUND

Topical minoxidil and oral finasteride are the only drugs approved for the treatment of androgenetic alopecia (AGA) in Spain. However, the management of this condition is highly variable because numerous treatments are used off-label. The main aim of this study was to describe the prescribing habits of dermatologists in Spain for male AGA (MAGA) and female AGA (FAGA).

MATERIAL AND METHODS

Descriptive cross-sectional study using online questionnaires completed by dermatologists working in Spain.

RESULTS

The responses of 241 dermatologists were analyzed. The most common treatments prescribed for MAGA were minoxidil (98%), oral finasteride (96%), nutricosmetics (44%), topical finasteride (37%), oral dutasteride (33%), platelet-rich plasma (14%), and low-level laser therapy (8%). For premenopausal FAGA, the most common treatments were topical minoxidil (98%), oral contraceptives (81%), nutricosmetics (72%), cyproterone acetate (58%), oral finasteride (39%), topical finasteride (39%), spironolactone (27%), platelet-rich plasma (20%), oral dutasteride (20%), oral flutamide (18%), and low-level laser therapy (7%). Finally, for postmenopausal FAGA, the most common treatments prescribed were topical minoxidil (98%), oral finasteride (84%), nutricosmetics (68%), topical finasteride (50%), oral dutasteride (35%), platelet-rich plasma (21%), spironolactone (16%), cyproterone acetate (16%), oral flutamide (9%), and low-level laser therapy (9%). A limitation of our study is that we did not analyze novel AGA treatments such as oral minoxidil and dutasteride mesotherapy.

CONCLUSIONS

The most common treatments prescribed for AGA by dermatologists in Spain are topical minoxidil, oral finasteride, and nutricosmetics for MAGA and postmenopausal FAGA and topical minoxidil, oral contraceptives, and nutricosmetics for premenopausal FAGA.

Activation of Wnt/β-catenin signaling is involved in hair growth-promoting effect of 655-nm red light and LED in in vitro culture model

Activation of the Wnt/β-catenin signaling pathway plays an important role in hair follicle morphogenesis and hair growth. Recently, low-level laser therapy (LLLT) was evaluated for stimulating hair growth in numerous clinical studies, in which 655-nm red light was found to be most effective and practical for stimulating hair growth. We evaluated whether 655-nm red light + light-emitting diode (LED) could promote human hair growth by activating Wnt/β-catenin signaling. An in vitro culture of human hair follicles (HFs) was irradiated with different intensities of 655-nm red light + LED, 21 h7 (an inhibitor of β-catenin), or both. Immunofluorescence staining was performed to assess the expression of β-catenin, GSK3β, p-GSK3β, and Lef1 in the Wnt/β-catenin signaling. The 655-nm red light + LED not only enhanced hair shaft elongation, but also reduced catagen transition in human hair follicle organ culture, with the greatest effectiveness observed at 5 min (0.839 J/cm²). Additionally, 655-nm red light + LED enhanced the expression of β-catenin, p-GSK3β, and Lef1, signaling molecules of the Wnt/β-catenin pathway, in the hair matrix. Activation of Wnt/β-catenin signaling is involved in hair growth-promoting effect of 655-nm red light and LED in vitro and therefore may serve as an alternative therapeutic option for alopecia.

Systematic review of low-level laser therapy for adult androgenic alopecia

Alopecia is a common disorder affecting over half of the world's population. Within this condition, androgenic alopecia (AA) is the most common type, affecting 50% of males over 40 and 75% of females over 65. Anecdotal paradoxical hypertrichosis noted during laser epilation has generated interest in the possibility of using laser to stimulate hair growth. In this study, we aimed to critically appraise the application of low-level laser therapy for the treatment of AA in adults. A systematic review was performed on studies identified on Medline, EMBASE, Cochrane database, and clinicaltrials.org. Double-blinded randomized controlled trials were selected and analyzed quantitatively (meta-analysis) and qualitatively (quality of evidence, risk of bias). Low-level laser therapy appears to be a promising noninvasive treatment for AA in adults that is safe for self-administration in the home setting. Although shown to effectively stimulate hair growth when compared to sham devices, these results must be interpreted with caution. Further studies with larger samples, longer follow-up, and independent funding sources are necessary to determine the clinical effectiveness of this novel therapy.

Photobiomodulation therapy for androgenetic alopecia: A clinician's guide to home-use devices cleared by the Federal Drug Administration

The market for home-use photobiomodulation devices to treat androgenetic alopecia has rapidly expanded, and the Food and Drug Administration (FDA) has recently cleared many devices for this purpose. Patients increasingly seek the advice of dermatologists regarding the safety and efficacy of these hair loss treatments. The purpose of this guide was threefold: (1) to identify all home-use photobiomodulation therapy devices with FDA-clearance for treatment of androgenetic alopecia; (2) to review device design, features and existing clinical evidence; and (3) to discuss practical considerations of photobiomodulation therapy, including patient suitability, treatment goals, safety, and device selection. A search of the FDA 510(k) Premarket Notification database was conducted using product code "OAP" to identify all home-use devices that are FDA-cleared to treat androgenetic alopecia. Thirteen commercially available devices were identified and compared. Devices varied in shape, wavelength, light sources, technical features, price, and level of clinical evidence. To date, there are no head-to-head studies comparing the efficacy of these devices. Photobiomodulation therapy devices have an excellent safety profile and mounting evidence supporting their efficacy. However, long-term, high quality studies comparing these devices in diverse populations are lacking. As these devices become increasingly popular, dermatologists should be familiar with this treatment modality to add to their therapeutic armamentarium.

ABBREVIATIONS

AGA, androgenetic alopecia; FDA, Food and Drug Administration; IEC, International Electrotechnical Commission; LED, light-emitting diode; PBMT, photobiomodulation therapy.

Wnt/β-catenin and ERK pathway activation: A possible mechanism of photobiomodulation therapy with light-emitting diodes that regulate the proliferation of human outer root sheath cells

BACKGROUND

Outer root sheath cells (ORSCs) play important roles in maintaining hair follicle structure and provide support for the bulge area. The hair growth promoting effects of photobiomodulation therapy (PBMT) have been reported, but the mechanisms for this in human ORCs (hORSCs) have rarely been studied.

OBJECTIVE

The aim of this study was to investigate the effect of various wavelengths of light-emitting diode (LED) irradiation on human ORSCs (hORSCs).

METHODS

LED irradiation effects on hORSC proliferation and migration were examined with MTT assay, BrdU incorporation assay and migration assays. hORSCs were irradiated using four LED wavelengths (415, 525, 660, and 830 nm) with different low energy levels. LED irradiation effects on the expression of molecules associated with the Wnt/β-catenin signaling and ERK pathway, hair stem cell markers, and various growth factors and cytokines in hORSCs were examined with real-time PCR and Western blot assay. The effect of the LED-irradiated hORSCs on cell proliferation of human dermal papilla cells (hDPCs) was examined with co-culture and MTT assay.

RESULTS

PBMT with LED light variably promoted hORSC proliferation and suppressed cell apoptosis depending on energy level. LED irradiation induced Wnt5a, Axin2, and Lef1 mRNA expression and β-catenin protein expression in hORSCs. Phosphorylation of ERK, c-Jun, and p38 in hORSCs was observed after LED light irradiation, and ERK inhibitor treatment before irradiation reduced ERK and c-Jun phosphorylation. Red light-treated hORSCs showed substantial increase in IL-6, IL-8, TNF-a, IGF-1, TGF-β1, and VEGF mRNA. Light irradiation at 660 and 830 nm projected onto hORSCs accelerated in vitro migration. LED-irradiated hORSCs increased hDPCs proliferation when they were co-cultured. The conditioned medium from LED-irradiated hORSCs was sufficient to stimulate hDPCs proliferation.

CONCLUSION

These results demonstrate that LED light irradiation induced hORSC proliferation and migration and inhibited apoptosis in vitro. The growth-promoting effects of LEDs on hORSCs appear to be associated with direct stimulation of the Wnt5a/β-catenin and ERK signaling pathway. Lasers Surg. Med. 49:940-947, 2017. © 2017 Wiley Periodicals, Inc.

Growing evidence of the beneficial effects of a marine protein-based dietary supplement for treating hair loss

BACKGROUND

Hair loss is a common condition among women with a range of causes including nutritional deficiencies.

AIMS

To review the clinical data supporting the use of an oral marine supplement designed to promote hair growth.

PATIENTS/METHODS

Adult women with temporary thinning hair. Following an initial pilot study, five randomized, double-blind studies assessed the effectiveness of the oral marine supplement for promoting hair growth. Each study was approved by one or more institutional review boards.

RESULTS

Together, these studies demonstrated the ability of oral marine supplements to increase the growth of terminal and vellus hairs, increase the diameter of terminal and vellus hairs, and decrease hair loss. This product is beneficial for men as well as women.

CONCLUSIONS

A dietary supplement containing a marine complex and other natural ingredients can safely and effectively promote hair growth and decrease hair shedding in women and men with thinning hair.

New Treatments for Hair Loss

The treatment of hair loss is an important part of clinical dermatology given the prevalence of the problem and great impact on patients' quality of life. Many new treatments have been introduced in recent years. This review summarizes the main ones in 4 groups: a) For androgenetic alopecia, we discuss new excipients for oral minoxidil, dutasteride, and finasteride as well as new forms of topical application; prostaglandin agonists and antagonists; low-level laser therapy; and regenerative medicine with Wnt signaling activators and stem cell therapy. b) For alopecia areata, Janus kinase inhibitors are reviewed. c) For frontal fibrosing alopecia, we discuss the use of antiandrogens and, for some patients, pioglitazone. d) Finally, we mention new robotic devices for hair transplant procedures and techniques for optimal follicular unit extraction.

Effectiveness of Laser Therapy in the Management of Recurrent Aphthous Stomatitis: A Systematic Review

Objectives. Laser therapy is a promising new treatment for patients with recurrent aphthous stomatitis (RAS). However, the clinical effect and security issue of laser therapy remain controversial. This systematic review was conducted to evaluate the clinical effectiveness and security of laser treatment in RAS patients. Methods. Five electronic databases were searched (MEDLINE (PubMed), EMBASE, ScienceDirect, the Cochrane Library, and Web of Science) to identify all studies that were about randomized controlled clinical trials, involving the effect of laser therapy in RAS patients. Conclusion. Twenty-three studies were retained for full-text analysis after screening the titles and abstracts of potential articles, but only 10 studies satisfied the inclusion criteria after the full texts were reviewed. The included studies reported a comparison of the effectiveness between the laser treatment and placebo laser therapy (or conventional drug therapy) when managing the RAS patients. It can be concluded that laser therapy has the superiority in relieving ulcer pain and shortening healing time when compared with placebo group or medical treatment group. Although laser therapy is a promising effective treatment for RAS, high-quality clinical studies with large sample size must be further performed to confirm the effectiveness of this therapy.