Low-dose topical 5-aminolevulinic acid photodynamic therapy in the treatment of different severity of acne vulgaris

A novel H‑tert immortalized human sebaceous gland cell line (XL-i-20) for the investigation of photodynamic therapy

BACKGROUND

Acne vulgaris is a species-specific human disease. To date, there has been no established human sebocyte cell line of Asian origin. Our previous study has demonstrated the efficacy of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in the treatment of acne vulgaris, primarily attributed to its cytotoxic properties; however, its regulatory mechanism remains largely unknown.

OBJECTIVES

To establish an immortalized human sebocyte cell line derived from Chinese population and investigate the underlying mechanism of ALA-PDT.

METHODS

Human primary sebocytes were transfected with the human tert gene (h‑tert). The biological characteristics, including cell proliferation, cell markers, and sebum secretion function, were compared between primary sebocytes and the immortalized sebocytes (XL-i-20). Stimulations such as ALA-PDT, were applied respectively to both primary sebocytes and XL-i-20 cells to assess changes in their cellular functions. The transcriptome differences between primary sebocytes and XL-i-20 sebocytes were investigated using RNA-seq analysis. The XL-i-20 cell line was used to establish a sebaceous gland (SG) organoid culture, serving as a representative model of SG for the investigation of ALA-PDT.

RESULTS

The h‑tert immortalized sebocyte cell line exhibited the ability to be consecutively cultured for more than fifty passages. Both primary and immortalized cells expressed sebocyte markers such as epithelial membrane antigens (EMA, or MUC-1), Cytokeratin 7 (CK7) and adipose differentiation-related protein associated antigens (ADRP), and maintained sebum secretion function. The proliferative capacity of XL-i-20 was found to be significantly higher than that of primary sebocytes. The responses of XL-i-20 to ALA-PDT were indistinguishable from those elicited by primary sebocytes. Cell viability and sebum secretion were decreased after ALA-PDT in both two cell lines, and lipid-related proteins (SREBP-1/PPARγ) were down-regulated. The transcriptome data consistently demonstrated upregulation of genes related to inflammatory responses and downregulation of genes involved in lipid metabolism in both cell types following PDT. The analysis of common differential genes of primary sebocytes and XL-i-20 sebocytes post ALA-PDT showed that TNF signaling pathways, MAPK signaling pathways and JAK-STAT signaling pathways were activated. The SG organoids were spherical, which expressed markers of FANS and PLET1. Ki-67 was down-regulated after ALA-PDT.

CONCLUSIONS

We have developed an h‑tert immortalized sebocyte cell line from an Asian population. The cell line, XL-i-20, maintains the essential characteristics of its parent primary sebocytes. Moreover, XL-i-20 sebocyte exhibited a significant respond to ALA-PDT, demonstrating comparable phenotypic and molecular changes to primary sebocytes. Therefore, XL-i-20 and its derived SG organoid serve as appropriate in vitro models for investigating the efficacy and mechanisms of ALA-PDT in SG-related diseases.

Long-Term Improvement of Different Types of Acne Vulgaris Using a Mild Photodynamic Therapy Protocol with BF-200 ALA Gel: A Series of Cases

Background: Photodynamic therapy (PDT) can be a promising alternative for patients with acne vulgaris. Our study aimed to evaluate the efficacy and safety of red light photodynamic therapy with BF-200 ALA gel in the treatment of different types of acne vulgaris. Methods: We performed a retrospective, observational study of a series of 22 cases. All patients were treated according to a mild PDT protocol. After a careful wash of the affected skin areas, BF-200 ALA gel was applied to the skin in a thin layer and incubated for 30 min, followed by illumination using narrow-spectrum red light (635 nm) at a dose of 4 J/cm2. Most patients received one (36.4%), two (27.3%), or three (22.7%) PDT sessions. About a third of the patients received concomitant acne treatment with topical retinoids. Results: Patients of 25.1 ± 8.9 years suffering from papulopustular (45.5%), nodular (27.3%), and comedonal acne (27.3%) in the face were included. Irrespective of acne type or severity, 95.5% of patients had good or excellent responses to the treatment with PDT (≥60% lesion clearance). We found no association between concomitant acne medication and the favorable results achieved by PDT. Most patients reported no adverse events (72.7%), except for six patients who experienced erythema. The good efficacy results were maintained over a follow-up period of 12.5 ± 10.8 months. Conclusions: In this study, we show that PDT with BF-200 ALA gel and low light dose is an effective and long-lasting option for the treatment of different acne types.

5-Aminolevulinic acid photodynamic therapy versus minocycline for moderate-to-severe rosacea: A single-center, randomized, evaluator-blind controlled study

BACKGROUND

5-Aminolevulinic acid photodynamic therapy (ALA-PDT) showed potential to treat rosacea according to recent studies; however, a lack of clinical evidence and unclear adverse effects limit its use.

OBJECTIVE

To compare the effect of ALA-PDT vs minocycline on rosacea.

METHODS

In this single-center, randomized, evaluator-blind, controlled study, patients with moderate-to-severe rosacea were allocated to receive 3 to 5 sessions of ALA-PDT or 8 weeks of 100 mg daily minocycline treatment, followed by a 24-week follow-up.

RESULTS

Of all the 44 randomized patients, 41 received complete treatment (ALA-PDT: 20 and minocycline: 21 patients). At the end of treatment, ALA-PDT showed noninferior improvement of papulopustular lesions and Rosacea-specific Quality of Life compared with minocycline (median reduction of lesion count: 19 vs 22, median change of Rosacea-specific Quality of Life score: 0.48 vs 0.53). The Clinician's Erythema Assessment success of ALA-PDT was lower than that of minocycline's (35% vs 67%). Demodex density and relapse rate were comparable in both groups. Erythema, mild pain, and exudation were the most common adverse reactions of ALA-PDT.

LIMITATIONS

Limited sample size restricted us from drawing further conclusions.

CONCLUSION

As minocycline does, ALA-PDT can improve rosacea mainly in papulopustular lesions and patients' quality of life, indicating a new option for rosacea.

The updates and implications of cutaneous microbiota in acne

Acne is a chronic inflammatory skin disorder that profoundly impacts the quality of life of patients worldwide. While it is predominantly observed in adolescents, it can affect individuals across all age groups. Acne pathogenesis is believed to be a result of various endogenous and exogenous factors, but the precise mechanisms remain elusive. Recent studies suggest that dysbiosis of the skin microbiota significantly contributes to acne development. Specifically, Cutibacterium acnes, the dominant resident bacterial species implicated in acne, plays a critical role in disease progression. Various treatments, including topical benzoyl peroxide, systemic antibiotics, and photodynamic therapy, have demonstrated beneficial effects on the skin microbiota composition in acne patients. Of particular interest is the therapeutic potential of probiotics in acne, given its direct influence on the skin microbiota. This review summarizes the alterations in skin microbiota associated with acne, provides insight into its pathogenic role in acne, and emphasizes the potential of therapeutic interventions aimed at restoring microbial homeostasis for acne management.

Hyaluronic acid-FGF2-derived peptide bioconjugates for suppression of FGFR2 and AR simultaneously as an acne antagonist

Acne is a chronic skin condition that has serious consequences for mental and social well-being because it frequently occurs on the face. Several acne treatment approaches have commonly been used but have been hampered by side effects or weak activity. Thus, the investigation of the safety and efficacy of anti-acne compounds is of considerable medical importance. Herein, an endogenous peptide (P5) derived from fibroblast growth factors 2 (FGF2) was conjugated to the polysaccharide hyaluronic acid (HA) to generate the bioconjugate nanoparticle HA-P5, which suppresses fibroblast growth factor receptors (FGFRs) to significantly rehabilitate acne lesions and reduce sebum accumulation in vivo and in vitro. Moreover, our results show that HA-P5 inhibits both fibroblast growth factor receptor 2 (FGFR2) and androgen receptor (AR) signalling in SZ95 cells, reverses the acne-prone transcriptome, and decreases sebum secretion. Furthermore, the cosuppression mechanism revealed that HA-P5 blocks FGFR2 activation, as well as the YTH N6-methyladenosine RNA binding protein F3 (YTHDF3) downstream molecules, including an N6-methyladenosine (m6A) reader that facilitates AR translation. More importantly, a significant difference between HA-P5 and the commercial FGFR inhibitor AZD4547 is that HA-P5 does not trigger the overexpression of aldo-keto reductase family 1 member C3 (AKR1C3), which blocks acne treatment by catalyzing the synthesis of testosterone. Overall, we demonstrate that a polysaccharide-conjugated and naturally derived oligopeptide HA-P5 can alleviate acne and act as an optimal FGFR2 inhibitor and reveal that YTHDF3 plays a crucial role in signalling between FGFR2 and AR.

Photodynamic therapy treats acne by altering the composition of the skin microbiota

BACKGROUND

Acne is the eighth-most prevalent inflammatory skin disease with no optimal treatment. Photodynamic therapy (PDT) is an effective treatment for severe acne.

AIMS

The effect of PDT on the composition and diversity of skin microflora in severe acne patients was studied.

MATERIALS AND METHODS

A total of 18 patients with severe acne and 8 healthy individuals were selected for this study. Patients were treated with 5-aminolevulinic acid-mediated PDT once a week three times in total; the skin microbiome was measured by 16S ribosomal RNA gene sequencing before and after treatment (1 week after each PDT).

RESULTS

The microflora composition was different between healthy controls and patients, and between patients before and after treatment. Alpha diversity indices were lower in patients than those in control. There were 15 bacterial genera with high relative abundance that had noticeable changes during treatment. At the genus level,particularly Cutibacterium acnes (C. acnes formerly Propionibacterium acnes), there was no statistically significant difference among different group. The abundances of Staphylococcus epidermidis and Staphylococcus aureus were low.

DISCUSSION

The microbial composition is different between severe acne patients acne patients and healthy individuals. The therapeutic efficacy of severe acne treated with PDT is associated with the composition and diversity of skin microbiota.

CONCLUSION

The skin microbial composition changes after PDT treatment. PDT is an effective method for the treatment of severe acne.

Clinical practice Guidelines for 5-Aminolevulinic acid photodynamic therapy for acne vulgaris in China

A variety of evidence suggest that 5-Aminolevulinic acid-based photodynamic therapy (ALA-PDT) is clinically effective in management of acne vulgaris. Several clinical guidelines for acne recommend PDT as an alternative treatment modality for severe acne. However, there is a lack of detailed clinical guideline for PDT in acne treatment. To propose up-to-date, evidence-based and practical recommendations on application of ALA-PDT for acne vulgaris, dermatologists and PDT experts from the Photodynamic Therapy Research Center of the CMA and Photodynamic Therapy Rehabilitation Training Center of CARD achieved consensus and guidelines based on careful evaluation of published literature, expert opinions and experience. ALA-PDT plays a therapeutic role in all four major pathogenesis of acne, and is suitable for moderate to severe acne and scar-prone acne, especially for patients who cannot tolerate or refused systemic antibiotics and isotretinoin. The efficacy and adverse reactions of ALA-PDT are closely related to therapeutic parameters including ALA concentration, incubation time, light source and dosage. Proper pretreatment helps to improve transdermal absorption of ALA and enhances its efficacy. We reviewed and proposed recommended protocols for four PDT procedures including conventional PDT (C-PDT), modified painless PDT (M-PDT), intense pulsed light PDT (IPL-PDT) and daylight PDT (DL-PDT). M-PDT with lower ALA concentration (3-5%), shorter incubation time (30 mins), and lower dose but prolonged illumination (630nm, 40-60 mW/cm², 150 J/cm²) can improve lesions of moderate to severe acne vulgaris effectively with minimal pain and easier manipulation, and thus was recommended by Chinese dermatologists. Lastly, management of adverse reactions were addressed.

The Use of Lasers and Light Devices in Acne Management: An Update

Acne vulgaris is a disease of the pilosebaceous unit and the most common inflammatory dermatosis worldwide. It is also associated with significant economic burden. Limitations of conventional topical and systemic treatments include long treatment course, intolerable adverse effects, antibiotic resistance, and patient compliance. Therefore, laser and light-based interventions present as alternative options over the past decade and have been used in combination with conventional pharmacological therapies and other physical modalities. An updated overview on the use of lasers and light-based devices in acne management is presented to help clinicians understand the safety and efficacy of these treatment options. The effectiveness of neodymium:yttrium aluminum garnet (Nd:YAG) for treating acne is supported by more high-level studies compared with other laser devices. There is limited evidence to support the use of CO₂ lasers, potassium titanyl phosphate lasers, and 1565-nm non-ablative fractional lasers for treating acne. Among light devices, photodynamic therapy is the most studied, showing higher efficacies than some of the conventional topical and oral acne therapies. Intense-pulsed light and blue light therapies also show favorable outcomes. A limitation is that most studies are non-randomized and lack a control group, and report on a variety of device settings, treatment regimens, and outcome measures, making it challenging to summarize and generalize findings. Although the use of laser and light devices to treat acne is promising, further work with randomized controlled study designs and larger sample sizes will provide improved guidance on the application of these modalities.

Treatment of androgenetic alopecia with 5-aminolevulinic acid photodynamic therapy: A randomized, placebo-controlled, split-scalp study of efficacy and safety

BACKGROUND AND OBJECTIVES

Androgenetic alopecia (AGA) is one of the most common hair loss disorders. Treatment options for AGA are limited . New therapies for AGA are clinically needed. 5-aminolevulinic acid photodynamic therapy (ALA-PDT) is widely applied in diseases involving the pilosebaceous unit. However, limited research has explored the efficacy of ALA-PDT in treating alopecia. Some studies reported hair regrowth after PDT in alopecia areata patients, but the efficacy of ALA-PDT on AGA remains unclear. The objective of this study is to evaluate the efficacy and safety of ALA-PDT for the treatment of AGA.

METHODS

A randomized, placebo-controlled, split-scalp clinical study was conducted. Subjects with AGA received six sessions of 5% ALA-PDT on one half of their scalp and the red-light therapy on the other half. The treatments were applied every two weeks for six sessions on each subject.

RESULTS

There were 7 subjects enrolled in this study. No significant difference in hair density was observed between the red-light treatment and ALA-PDT treatment. The hair density in the ALA-PDT treated half of the scalp significantly decreased 1 week after the treatment, then it increased, and no statistical difference was found at 12 weeks after the last treatment compared to the baseline. There was no significant improvement in hair growth according to a 7-point scale and the subjects' self-assessments. The main adverse effects in ALA-PDT treatment were mild edema and tolerable pain, and no adverse effect was observed in red-light treatment.

CONCLUSIONS

6 sessions of 5% ALA-PDT did not increase the hair growth of AGA patients, but slightly suppressed the sebum secretion on the scalp. The adverse effects of ALA-PDT were mild, which indicated safety and tolerability of this treatment.

Chinese guidelines on the clinical application of 5-aminolevulinic acid-based photodynamic therapy in dermatology (2021 edition)

Photodynamic Therapy with 5-aminolevulinic acid (ALA-PDT) has been widely applied in the treatment of skin diseases in China. To further standardize, guide, and promote the clinical applications of ALA-PDT in dermatology, the Chinese Society of Dermatology, Chinese Association of Rehabilitation Dermatology, Photomedicine Therapeutic Equipment Group of Committee on Skin Disease, and Cosmetic Dermatology of China Association of Medical Equipment invited relevant experts engaged in ALA-PDT to revise and update the first edition of "Clinical application of 5-aminolevulinic acid-based photodynamic therapy: an expert consensus statement" and establish a more current edition, to provide an updated reference for Chinese dermatologists in clinical practice. In the guideline, the expert group reached consensus opinions on ALA-PDT with regard to mechanisms of action, therapeutic protocol, clinical applications, adverse reactions and countermeasures, precautions, care, and evaluation of efficacy.

The effects of ALA-PDT on microbiota in pilosebaceous units of patients with severe acne: A metagenomic study

BACKGROUND

5-aminolevulinic acid mediated photodynamic therapy (ALA-PDT) is increasingly used to control severe acne. However, its impact on skin microbiota remains uncertain.

OBJECTIVES

We aimed to compare the makeup, diversity, and function of the microbiota in pilosebaceous units of patients with severe acne before and after ALA-PDT.

METHODS

A longitudinal cohort study was performed on 11 participants with severe facial acne. All patients were given 5%ALA-PDT every two weeks for three sessions in total. The contents of lesions were sampled for metagenomic sequencing at baseline and two weeks after the first ALA-PDT session.

RESULTS

Cutibacterium acnes was the most dominant species followed by Staphylococcus epidermidis and Pseudomonas fluorescens. Treatment with ALA-PDT led to clinical improvements in acne severity concurrent with a significant reduction in the relative abundance of C. acnes, while P. fluorescens increased significantly after ALA-PDT. No significant change was identified in other species. ALA-PDT administration was associated with an increased microbiota diversity and reductions in the relative abundance of the functional genes involved in energy metabolism and DNA replication.

CONCLUSIONS

ALA-PDT plays a therapeutic role by killing C. acnes, increasing P. fluorescens and the microbiome diversity, while inhibiting the function of microbiota in pilosebaceous units of severe acne.

Viral Nanoparticle System: An Effective Platform for Photodynamic Therapy

Photodynamic therapy (PDT) is a promising therapy due to its efficiency and accuracy. The photosensitizer is delivered to the target lesion and locally activated. Viral nanoparticles (VNPs) have been explored as delivery vehicles for PDT in recent years because of their favorable properties, including simple manufacture and good safety profile. They have great potential as drug delivery carriers in medicine. Here, we review the development of PDT photosensitizers and discuss applications of VNP-mediated photodynamic therapies and the performance of VNPs in the treatment of tumor cells and antimicrobial therapy. Furthermore, future perspectives are discussed for further developing novel viral nanocarriers or improving existing viral vectors.

Combination of surgery and photodynamic therapy for the treatment of cystic acne of the scalp

Cystic acne of the scalp is relatively resistant to conventional treatment because of its thick wall and deep cavity. This study was conducted as a comparative analysis of clinical outcomes of single surgery and those of surgery combined with photodynamic therapy for cystic acne of the scalp. Ten patients were treated only with surgical incisions and drainage of pus and necrotic tissues, and another ten patients were treated with photodynamic therapy immediately after surgery, followed by two weekly cycles thereafter. The combination treatment group reported better outcomes than the single surgery group in terms of duration of wound healing, the number of dressing changes, pain score at the time of dressing change, and recurrence rate. Our study demonstrateds that the combination of surgery and photodynamic therapy may have pronounced effects on the treatment for cystic acne of the scalp.

Photodynamic Therapy for Photodamage, Actinic Keratosis, and Acne in the Cosmetic Practice

Photodynamic therapy is the combination of the initial application of a photosensitive chemical on the skin and then using typically a blue filter light of varying spectrums. This treatment protocol has been more useful and functional than other chemical peels and lasers for a variety of conditions. There has been efficacy in antiviral treatments, such as herpetic lesions; malignant cancers of the head and neck; and lung, bladder, and skin cancers. It has been tested for prostate cancers, cervical cancer, colorectal cancer, lung cancer, breast cancer, esophageal cancer, stomach cancer, pancreatic cancer, vaginal cancer, gliomas, and erythroplasia of Queyrat.

Photodynamic therapy for severe facial acne vulgaris with 5% 5-aminolevulinic acid vs 10% 5-aminolevulinic acid: A split-face randomized controlled study

BACKGROUND

Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) has been described as an effective treatment for severe acne. However, very little evidence exists on the optimal concentration of ALA used in PDT for severe acne.

OBJECTIVES

To compare the efficacy and safety of PDT with 5% ALA vs 10% ALA in severe acne.

METHODS

Twenty-three patients with severe facial acne were randomly assigned to receive PDT with 5% ALA or 10% ALA on the left or right side of the face. Four PDT sessions were conducted with a light dose of 96 J/cm2 . The reduction rates of lesion counts between the two groups were compared at the week-4 and week-12 follow-up visits. Effective rate at the week-12 visit was the primary clinical outcome. Pain and other side effects were evaluated at each visit.

RESULTS

The decrease in inflammatory lesions in the 10% ALA group was greater than that in the 5% ALA group at both week-4 (79.2% vs 62.5%, P = 0.009) and week-12 follow-up visits (88.5% vs 78.3%, P = 0.018), while the decrease in noninflammatory lesion counts between the two groups was not statistically significant at each follow-up visit. The effective rate in the 10% ALA group was significantly higher than that in the 5% ALA group (95.7% vs 69.6%, P = 0.02). No significant difference was observed in pain scores between the two groups except in the first treatment session.

CONCLUSIONS

Photodynamic therapy using 10% ALA was more effective for severe acne than PDT using 5% ALA.

Randomized controlled double-blind study of a cleanser composed of 5-aminolevulinic acid and peptides on mild and moderate acne vulgaris

BACKGROUND

Existing treatments of acne vulgaris may be complicated or elicit undesirable side effects. Therefore, new and safe therapeutic modalities are needed.

OBJECTIVES

We investigated the effects of a cleanser with 5-aminolevulinic acid and peptides on mild to moderate acne vulgaris.

METHODS

Sixty volunteers with mild to moderate acne vulgaris (IGA grade II-III) were randomly assigned to treatment or control groups of thirty respectively. Participants cleansed their faces twice a day for 8 weeks with either a cleanser with 5-aminolevulinic acid and peptides (treatment) or with basic cleanser (control). The number of acne lesions (comedones, papules, pustules, and nodules), Michaelson's acne severity, and IGA were measured every 2 weeks and patient satisfaction and adverse events at week 8.

RESULTS

Mean number of inflammatory acne lesions in treatment group decreased from 5.9 at baseline to 4.5 at week 4 and 4.1 at week 8 (in particular, P < .05). The mean number of noninflammatory lesions in treatment group decreased from 11.4 at baseline to 8.8 at week 4 and 7.4 at week 8 (in particular, P < .05). The mean value of Michaelson's acne severity index and IGA in treatment group also decreased from baseline to week 4 and week 8 (both in particular, P < .05). Investigator's assessment and patient satisfaction in treatment group at week 8 were better than control group. Adverse events in two groups were similar.

CONCLUSIONS

We think the cleanser with 5-aminolevulinic acid and peptides is a useful and safe therapeutic agent for mild to moderate acne vulgaris.

Comparative Study Of Photodynamic Therapy With Riboflavin-Tryptophan Gel And 13% 5-Aminolevulinic Acid In The Treatment Of Mild To Moderate Acne Vulgaris

Background

Non-invasive photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) has been used as an alternative acne treatment for many years. Riboflavin and tryptophan are newly introduced photosensitizers.

Objective

To compare the efficacy of PDT with riboflavin-tryptophan (RT) gel with that of 13% ALA for the treatment of facial acne.

Methods

We performed a double-blind, split-face study of 37 subjects with mild to moderate facial acne vulgaris. RT gel was applied to half of the face, and 13% ALA was applied to the other half. Then, the whole face was irradiated using a blue light-emitting diode for 20 mins. Four treatment sessions were performed over a 4-week duration, at 1-week interval. The acne lesion counts and acne severity were assessed. Sebum secretion, Propionibacterium acne colonization, pore size, and skin texture were also evaluated.

Results

PDT with RT gel demonstrated good efficacy, non-inferior to ALA for acne treatment, with a significant reduction in acne lesion counts, severity grading, porphyrin, and sebum output. The pore size and skin texture were improved. Side-effects were minimal and well tolerated in all subjects.

Conclusion

PDT therapy with RT gel is an effective alternative treatment for acne vulgaris.

Chlorin, Phthalocyanine, and Porphyrin Types Derivatives in Phototreatment of Cutaneous Manifestations: A Review

Recent scientific research has shown the use of chlorin, phthalocyanines, and porphyrins derivatives as photosensitizers in photodynamic therapy in the treatment of various pathologies, including some of the major skin diseases. Thus, the main goal of this critical review is to catalog the papers that used these photosensitizers in the treatment of acne vulgaris, psoriasis, papillomavirus infections, cutaneous leishmaniasis, and skin rejuvenation, and to explore the photodynamic therapy mechanisms against these conditions alongside their clinical benefits.

[Light-based inflammatory acne treatments]

Light-based acne treatments may represent a new emerging treatment for acne that does not increase the risk of bacterial resistance and they may be potentially effective with a favorable safety profile. Current data show that photodynamic therapy reduces inflammatory lesions and significantly improves acne. However, there is no consensus on the optimal implementation in the treatment of acne. In addition to topically applied photodynamic therapy, intense pulsed light, pulsed dye lasers, potassium-titanyl-phosphate lasers, infrared diode lasers, broad-spectrum continuous-wave light sources (red light, blue-red light) have been introduced as alternative treatments. Since well-designed studies to evaluate their efficacy versus traditional medical therapies are lacking and standardized regimens have not been agreed upon, procedures including laser, intense pulsed light, and photodynamic therapy should currently not be considered first-line treatment for inflammatory acne.

Optimization of hydrogel containing toluidine blue O for photodynamic therapy in treating acne

Antibiotics and photodynamic therapy (PDT) are widely employed in curing acne. However, antibiotics as an effective treatment would lead to bacterial resistance and severe side effects. In this study, we aimed to develop a novel TBO hydrogel, which could prolong the retention time of photosensitizer (TBO) at the lesion site and improve therapeutic effect. In vitro antibacterial experiments (against Staphylococcus aureus and Escherichia coli), the response surface methodology was used to optimize the formulation of TBO hydrogel. The results indicated that the optimal formulation was 0.5% (v/v) carbomer, 0.01 mg/mL TBO, 0.5% (v/v) ethanol concentration, 0.5% (v/v) Tween 80, the mass ratio of NaOH to carbomer of 0.4 (w/w). The TBO hydrogel formulation showed the strong antibacterial activity for Propionibacterium acnes. The stability, pH, and antibacterial activity of TBO hydrogel did not significantly change under 4 °C, 25 °C, and 40 °C during 6-week storage. Furthermore, TBO combined with carbomer hydrogel showed the 51.28% (4 h) and 69.80% (24 h) release. In summary, the hydrogel TBO might be a vital therapeutic strategy to promote the PDT applied in the topical therapy of acne. Graphical abstract A TBO hydrogel for photodynamic therapy in the treatment of acne.

What is the most relevent factor causing pain during ALA-PDT? A multi-center, open clinical pain score research trial of actinic keratosis, acne and condylomata acuminata

BACKGROUND

To date, it has been reported that the intrinsic factors(lesions location, lesions area, disease tynpes) and extrinsic factors(fluence rate) contribute to the pain during 5-aminolevulinic acid photodynamic therapy (ALA-PDT). But there are few studies on pain during ALA-PDT and lack of sufficient clinical evidence related to the pain intensity.

OBJECTIVE

To investigate pain intensity and its relative factors during ALA-PDT and to provide clinical implication.

METHODS

The pain numeric rating scale (PNRS) score was used to evaluate the patients' pain intensity at different times during ALA-PDT irradiation from 0 to 10 min during treatment. Gender, age, lesions location, lesions area, ALA concentration and fluence rate were recored.

RESULTS

The trial enrolled 274 patients in total, including 118 acne patients (in face), 30 actinic keratosis(AK)patients(in face), 126 Condylomatata acuminate patients(in genitalia). The average pain score in PDT was highest in the patients with actinic keratosis(7.3 ± 0.7), and that of condylomata acuminata was the lowest (4.5 ± 1.1) (p < 0.05). The highest pain score in patients with AK, acne and condylomata acuminata was 8, 6 and 6 respectively which occurred at 4 min, 4 min and 6 min respectively. The pain score of males was higher compared with females in all of the three diseases (p < 0.05). The pain score of facial diseases (5.6 ± 1.2) was higher than that of the genitalia (4.5 ± 1.1) (p < 0.05). The lesions area was positively correlated with the pain score (p < 0.05). In facial diseases, the pain score of patients with high fluence rate (7.3 ± 0.7) was higher than patients with low fluence rate (5.1 ± 0.9) (p < 0.05).

CONCLUSIONS

Intrinsic and extrinsic factors both correlate with pain during PDT. Intrinsic factors are difficult to change, so extrinsic factors are the key point to control. We can reduce the fluence rate and extend the treatment time, relieving pain intensity while still ensuring equivalent efficacy.

A new optical intra-tissue fiber irradiation ALA-PDT in the treatment of acne vulgaris in rabbit model: improved safety and tolerability

Background

Photodynamic therapy with topical aminolevulinic acid (ALA-PDT) has been suggested to be effective in treatment of acne vulgaris. However, adverse events occur during and after treatment.

Objectives

To compare the efficacy and tolerability of optical intra-tissue fiber irradiation (OFI) ALA-PDT versus traditional ALA-PDT in treatment of acne vulgaris in rabbit models.

Methods

Twenty-five rabbits of clean grade were used. Twenty rabbits were randomly selected to establish acne model and the other five were used as control. Rabbits in model group (40 ears) were further divided into four groups (10 ears/group): I, OFI-ALA-PDT with the head of optical fiber inserted into the target lesion (intra-tissue); II, traditional ALA-PDT group; III, OFI group; IV, blank control group without any treatment. Uncomfortable symptoms, adverse events, and effectiveness rates were recorded on post-treatment day 14, 30, and 45.

Results

On post-treatment day 14, the effectiveness rate in OFI-ALA-PDT group was obviously higher than that of the other three groups (P<0.05). However, no improved effects were observed in OFI-ALA-PDT group on day 30 and 45. During the period of treatment, the frequencies of uncomfortable symptoms in ALA-PDT group were obviously higher than those in the other three groups (P<0.05). The adverse event rate in OFI-ALA-PDT group was obviously lower than that of the ALA-PDT group (P<0.05).

Study limitations

The unblindness of the study and temporary animal models of acne induced may hamper the assessment and monitoring of the results, and future studies are still needed to clarify it further.

Conclusion

The OFI-ALA-PDT group (intra-tissue irradiation) showed no improved efficacy on treating rabbit ear acne but had higher safety and better tolerability.

A review of diagnosis and treatment of acne in adult female patients

This review focuses on the treatment options for adult female patients with acne. Acne in adult female patients may start during adolescence and persist or have an onset in adulthood. Acne has various psychosocial effects that impact patients’ quality of life. Treatment of acne in adult women specifically has its challenges due to the considerations of patient preferences, pregnancy, and lactation. Treatments vary widely and treatment should be tailored specifically for each individual woman. We review conventional therapies with high levels of evidence, additional treatments with support from cohort studies and case reports, complementary and/or alternative therapies, and new agents under development for the treatment of patients with acne.

Topical ALA-PDT as alternative therapeutic option in treatment-recalcitrant dermatosis: Report of 4 cases

BACKGROUND

Topical Photodynamic therapy (PDT) is widely acknowledged for its safety and effectiveness in treating oncologic skin diseases such as basal cell carcinoma, actinic keratosis and squamous cell carcinoma in situ. Despite its broad applications in dermatology, this method is a relatively new therapeutic option for treating inflammatory/infectious skin diseases.

OBJECTIVES

To determine whether topical PDT is a safe and effective treatment option in treating treatment-recalcitrant dermatosis.

OBSERVATIONS

We presented one of each case of Acne Vulgaris, facial flat warts, urethral meatus Condyloma Acuminatum and extramammary Paget's disease, where other treatment options were either ineffective or not feasible, then those patients underwent topical PDT and showed significant improvement with minimal side effects.

CONCLUSIONS

Topical PDT therapy may be applied in cases of Acne Vulgaris, facial flat warts, urethral meatus Condyloma Acuminatum and extramammary Paget's disease, where other treatment has shown no or minimal improvement, or in whom ablative or invasive procedure is to be avoided or not well tolerated.

Topical 5-aminolevulinic photodynamic therapy with red light vs intense pulsed light for the treatment of acne vulgaris: A spilit face, randomized, prospective study

5-Aminolevulinic acid photodynamic therapy (ALA-PDT) has been an effective method for treating acne vulgaris. Red light is the most widely used light source while Intense pulsed lights (IPL) is reported effective and well-tolerated. The purpose of this study was to evaluate the efficacy and adverse reactions of ALA-PDT with red light on acne compared with ALA-PDT with IPL.12 patients were recruited in the randomized, prospective and split-face study. 5% ALA cream were applied on the whole face with 2 hours' incubation before narrow band LED(633 ± 10 nm, 36 ∼ 108J/cm²) on one side of face and IPL(590∼1200 nm, 15∼17J/cm²) on the other side. Three treatment sessions were administered with 2-week interval each time and 8 weeks' follow up. The number of the total acne lesions and inflammatory lesions of the side treated by red light-PDT showed a relatively higher reduction rate that that by IPL-PDT (P < 0.05). Significant PpIX fluorescence decrease was observed only for the group of red light (P < 0.05). Lower pain intensity numeric rating scale values and Investigator's Global Severity Assessment (IGA) grading for erythema of the IPL side were observed (P<0.05).The results suggested that both red light and IPL are effective for ALA-PDT on acne vulgaris. ALA-PDT with red light may achieve better efficacy by more effective photobleaching of protoporphyrin IX (PpIX), whereas IPL may accomplish less adverse reactions and better tolerance.

Chlorin e6-mediated photodynamic therapy promotes collagen production and suppresses MMPs expression via modulating AP-1 signaling in P. acnes-stimulated HaCaT cells

BACKGROUND

Photodynamic therapy (PDT) is a clinically approved therapeutic for cancers and non-neoplastic diseases, based on the use of a photosensitizer activated by light. The feasibility of PDT depends on several factors, such as PDT dose, photosensitizer efficacy, type of light source, and target tissue irradiated.

METHODS

In this study, the second generation photosensitizer chlorin e6 (Ce6) and halogen light were used to investigate their PDT effect on the collagen production and MMPs expression of heat killed P. acnes-stimulated HaCaT cells. The mRNA levels of COL1A1, c-Jun, and c-Fos were detected by RT-PCR. The protein levels of MMPs, ERK and JNK were detected by western blot. The transactivation of AP-1 was detected by luciferase assay.

RESULTS

Ce6-based PDT markedly upregulated the mRNA level of COL1A1 and type I procollagen level; and at the same time downregulated the expression of MMPs in P. acnes-infected HaCaT cells. Moreover, Ce6-mediated PDT, in a dose dependent manner, inhibited P. acnes-induced phosphorylation of JNK and ERK, as wells as the phosphorylation of their downstream targets c-Jun and c-Fos. P. acnes-induced mRNA expression of c-Jun and c-Fos were also suppressed by Ce6-mediated PDT. The transactivation of AP-1 induced by P. acnes infection was also downregulated.

CONCLUSION

These results indicated that Ce6-mediated PDT with halogen light enhanced collagen production, but inhibited the expression of MMPs in P. acnes-infected HaCaT cells, by regulating AP-1 signals. This investigation provided the first molecular basis for the increase in collagen production by Ce6-mediated PDT, suggesting its potential use for scar amelioration and skin rejuvenation in acne treatment.

Current treatments of acne: Medications, lights, lasers, and a novel 650-μs 1064-nm Nd: YAG laser

The treatment of acne, especially severe acne, remains a challenge to dermatologists. Therapies include retinoids, antibiotics, hormones, lights, lasers, and various combinations of these modalities. Acne is currently considered a chronic rather than an adolescent condition. The appropriate treatment depends on the patient and the severity of disease. The purpose of this study was to review current therapies for acne of all severities and to introduce the 650-μs 1064-nm laser for the treatment of acne.

The Role of Photodynamic Therapy in Acne: An Evidence-Based Review

BACKGROUND

Acne vulgaris is a highly prevalent skin disorder that affects almost all adolescents and can persist into adulthood. Photodynamic therapy (PDT) is an emerging treatment for acne that involves the use of a photosensitizer in combination with a light source and oxygen.

METHODS

We performed a systematic review of the literature and critically evaluated the studies. Sixty-nine clinical trials, four case reports, and two retrospective studies met the inclusion criteria, and seven of the studies were high quality.

RESULTS

The most common photosensitizers used were 5-aminolevulinic acid and methyl aminolevulinate, and both showed similar response. Red light was the most frequently used light source, followed by intense pulsed light, and showed comparable results. Inflammatory and non-inflammatory lesions both responded to treatment, with inflammatory lesions showing greater clearance in most studies. Adverse events associated with PDT for acne were mild and included pain on illumination and post-procedural erythema and edema. PDT has been safely used in higher Fitzpatrick skin types (III-IV), although these patients had a higher risk of transient hyperpigmentation.

CONCLUSION

This review supports PDT as an efficacious treatment for acne and a good adjunctive treatment for mild to severe acne, especially in patients who have not responded to topical therapy and oral antibacterials, and are not great candidates for isotretinoin. Further studies are warranted to evaluate the optimal photosensitizers, light sources, incubation times, and number of treatments for PDT use in acne.

Low-Dose Topical 5-Aminolevulinic Acid Photodynamic Therapy in the Treatment of Different Severity of Acne Vulgaris

The objective of this article is to investigate the effectiveness and safety of photodynamic therapy (PDT) with 3.6 % topical aminolevulinic acid (ALA) and a short incubation time with red light in moderate to severe acne. One hundred and thirty-six patients with moderate to severe acne were treated with 3.6 % topical ALA-PDT for three sessions with an interval of 2 weeks. Patients were evaluated for efficacy and safety on week 2, 4, 6, 8, and 12 after the initial treatment. Most patients showed apparent clearance of acne lesions at the treated site after three sessions. The effective treatment rates were increased after the multiple therapies. The clinical outcomes are the best at 4 weeks after the final treatment. The total effectiveness rate and cure rate of the low-dose ALA-PDT procedure is 92.65 and 47.06 %, respectively. Thirty-one patients and nineteen patients showed apparent exacerbation of acne lesions before the 2nd and 3rd treatment, respectively, but all of them showed good or excellent improvement after a three-course treatment. A few patients showed mild relapse including papules and comedos at 8 weeks after the final treatment. No significant differences are found in the effects of different acne severity and different genders. Adverse reactions are mild and transient. A 3.6 % topical ALA-PDT with a short time incubation with red light is a simple and an effective treatment option for moderate to severe acne with mild side effects in Chinese people.

Light therapies for acne

BACKGROUND

Acne vulgaris is a very common skin problem that presents with blackheads, whiteheads, and inflamed spots. It frequently results in physical scarring and may cause psychological distress. The use of oral and topical treatments can be limited in some people due to ineffectiveness, inconvenience, poor tolerability or side-effects. Some studies have suggested promising results for light therapies.

OBJECTIVES

To explore the effects of light treatment of different wavelengths for acne.

SEARCH METHODS

We searched the following databases up to September 2015: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase and LILACS. We searched ISI Web of Science and Dissertation Abstracts International (from inception). We also searched five trials registers, and grey literature sources. We checked the reference lists of studies and reviews and consulted study authors and other experts in the field to identify further references to relevant randomised controlled trials (RCTs). We updated these searches in July 2016 but these results have not yet been incorporated into the review.

SELECTION CRITERIA

We included RCTs of light for treatment of acne vulgaris, regardless of language or publication status.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 71 studies, randomising a total of 4211 participants.Most studies were small (median 31 participants) and included participants with mild to moderate acne of both sexes and with a mean age of 20 to 30 years. Light interventions differed greatly in wavelength, dose, active substances used in photodynamic therapy (PDT), and comparator interventions (most commonly no treatment, placebo, another light intervention, or various topical treatments). Numbers of light sessions varied from one to 112 (most commonly two to four). Frequency of application varied from twice daily to once monthly.Selection and performance bias were unclear in the majority of studies. Detection bias was unclear for participant-assessed outcomes and low for investigator-assessed outcomes in the majority of studies. Attrition and reporting bias were low in over half of the studies and unclear or high in the rest. Two thirds of studies were industry-sponsored; study authors either reported conflict of interest, or such information was not declared, so we judged the risk of bias as unclear.Comparisons of most interventions for our first primary outcome 'Participant's global assessment of improvement' were not possible due to the variation in the interventions and the way the studies' outcomes were measured. We did not combine the effect estimates but rated the quality of the evidence as very low for the comparison of light therapies, including PDT to placebo, no treatment, topical treatment or other comparators for this outcome. One study which included 266 participants with moderate to severe acne showed little or no difference in effectiveness for this outcome between 20% aminolevulinic acid (ALA)-PDT (activated by blue light) versus vehicle plus blue light (risk ratio (RR) 0.87, 95% confidence interval (CI) 0.72 to 1.04, low-quality evidence). A study (n = 180) of a comparison of ALA-PDT (activated by red light) concentrations showed 20% ALA was no more effective than 15% (RR 1.05, 95% CI 0.96 to 1.15) but better than 10% ALA (RR 1.22, 95% CI 1.05 to 1.42) and 5% ALA (RR 1.47, 95% CI 1.19 to 1.81). The number needed to treat for an additional beneficial outcome (NNTB) was 6 (95% CI 3 to 19) and 4 (95% CI 2 to 6) for the comparison of 20% ALA with 10% and 5% ALA, respectively.For our second primary outcome 'Investigator-assessed changes in lesion counts', we combined three RCTs, with 360 participants with moderate to severe acne and found methyl aminolevulinate (MAL) PDT (activated by red light) was no different to placebo cream plus red light with regard to change in inflamed lesions (ILs) (mean difference (MD) -2.85, 95% CI -7.51 to 1.81), percentage change in ILs (MD -10.09, 95% CI -20.25 to 0.06), change in non-inflamed lesions (NILs) (MD -2.01, 95% CI -7.07 to 3.05), or in percentage change in NILs (MD -8.09, 95% CI -21.51 to 5.32). We assessed the evidence as moderate quality for these outcomes meaning that there is little or no clinical difference between these two interventions for lesion counts.Studies comparing the effects of other interventions were inconsistent or had small samples and high risk of bias. We performed only narrative synthesis for the results of the remaining trials, due to great variation in many aspects of the studies, poor reporting, and failure to obtain necessary data. Several studies compared yellow light to placebo or no treatment, infrared light to no treatment, gold microparticle suspension to vehicle, and clindamycin/benzoyl peroxide combined with pulsed dye laser to clindamycin/benzoyl peroxide alone. There were also several other studies comparing MAL-PDT to light-only treatment, to adapalene and in combination with long-pulsed dye laser to long-pulsed dye laser alone. None of these showed any clinically significant effects.Our third primary outcome was 'Investigator-assessed severe adverse effects'. Most studies reported adverse effects, but not adequately with scarring reported as absent, and blistering reported only in studies on intense pulsed light, infrared light and photodynamic therapies. We rated the quality of the evidence as very low, meaning we were uncertain of the adverse effects of the light therapies.Although our primary endpoint was long-term outcomes, less than half of the studies performed assessments later than eight weeks after final treatment. Only a few studies assessed outcomes at more than three months after final treatment, and longer-term assessments are mostly not covered in this review.

AUTHORS' CONCLUSIONS

High-quality evidence on the use of light therapies for people with acne is lacking. There is low certainty of the usefulness of MAL-PDT (red light) or ALA-PDT (blue light) as standard therapies for people with moderate to severe acne.Carefully planned studies, using standardised outcome measures, comparing the effectiveness of common acne treatments with light therapies would be welcomed, together with adherence to the Consolidated Standards of Reporting Trials (CONSORT) guidelines.

Effects of 5-aminolevulinic acid photodynamic therapy on TLRs in acne lesions and keratinocytes co-cultured with P. acnes

OBJECTIVE

To investigate the effect of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) on the expression of Toll like receptors (TLRs) in human keratinocytes and its role in acne treatment.

METHODS

TLR2 and TLR4 expression in acne lesions before and after ALA-PDT were examined by immunohistochemical assay. Primary keratinocytes were obtained from acne lesions, co-cultured with P. acnes and then treated with ALA-PDT using red or blue LED. Cytokines production were examined by ELISA, TLR2 and TLR4 gene expression by real-time PCR, and TLR2 and TLR4 protein expression by Western-blot assay.

RESULTS

The overexpression of TLR2 and TLR4 in acne lesion were detected, which became negative or weaker after ALA-PDT. The infection of P. acnes in keratinocytes could significantly increase the levels of early inflammatory cytokines (e.g. IL-1α, TNF-α and IL-8) (P<0.05). Such responses could be inhibited by ALA-PDT. P. acnes infection could also significantly increase TLR2 and TLR4 expressions in keratinocytes (P<0.05), which could be down-regulated by ALA-PDT.

CONCLUSIONS

ALA-PDT could inhibit innate immune responses in keratinocytes treated with P. acnes via TLRs pathways.

Photodynamic therapy inhibit Fibroblast Growth Factor-10 induced keratinocyte differentiation and proliferation through ROS in Fibroblast Growth Factor Receptor-2b pathway

5-aminolevulinic acid-photodynamic therapy (ALA-PDT) is known to be effective in several skin diseases such as acne, actinic keratoses, condyloma acuminata. However, some detailed mechanisms of ALA-PDT to treat these skin diseases still remain elusive. In this study, we aimed to investigate mechanism of ALA-PDT in in-vitro and in-vivo models. For in vitro, we use human keratinocyte cell line (HaCaT) cells. CCK-8 was used to detect cell proliferation activity, immunofluorescence and western blotting method to detect the content of keratin (K)1, K6, K16, protein kinase C (PKC), fibroblast growth factor receptor-2b (FGFR2b) protein, ELISA and RT-PCR to detect expression of interleukin (IL) 1α in the cell supernatant, and detect reactive oxygen species (ROS). For in vivo, we use 20 rabbits to induce hyperkeratosis acne model in their ear. Dermatoscope was used to see follicle hyperkeratosis and skin biopsy to analyze histology and immunohistochemical of PKC, FGFR2b, K1, K6 and K16. Results from this study suggest that ROS stimulated by ALA-PDT lead to inhibition of FGFR2b pathway in PKC downstream to cause reduction of IL1α expression, and eventually, keratinocytes differentiation and proliferation. Our data thus reveal a treatment mechanism of ALA-PDT underlying hyperkeratosis related dermatoses.

Off-label photodynamic therapy for recalcitrant facial flat warts using topical 5-aminolevulinic acid

The facial flat wart (verruca plana) is one of the most common reasons for dermatology and primary care visits. Although there are many therapeutic modalities, no single therapy has been proven to be completely curative. Case reports and uncontrolled studies suggested that photodynamic therapy (PDT) with topical 5-aminolevulinic acid (ALA) can effectively treat recalcitrant facial flat warts. A total of 12 patients with recalcitrant facial flat warts were enrolled in the study. ALA gel (10 %) was applied topically to lesions and incubated for 3 h. The lesions were irradiated by an LED light of 630 ± 10 nm at dose levels of 60-100 mW/cm. Clinical assessment was conducted before and after every treatment for up to 24 weeks. Among the ten patients completing three sessions of ALA-PDT, five had complete lesions clearance, and the other five patients were significantly improved. At the 24-week follow-up, the average effective rate was 88.8 %, with no recurrences. No significant side effects were reported. A low-dose topical ALA-PDT regimen using 10 % ALA, 3 h incubation, and a red light source for three treatment sessions are suggested as the optimal scheme for the treatment of recalcitrant flat warts on the face in Chinese patients. Superior efficacy is found in elevated or active period lesions with mild side effects.

Guidelines of care for the management of acne vulgaris

Acne is one of the most common disorders treated by dermatologists and other health care providers. While it most often affects adolescents, it is not uncommon in adults and can also be seen in children. This evidence-based guideline addresses important clinical questions that arise in its management. Issues from grading of acne to the topical and systemic management of the disease are reviewed. Suggestions on use are provided based on available evidence.

Use of Photosensitizers in Semisolid Formulations for Microbial Photodynamic Inactivation

Semisolid formulations, such as gels, creams and ointments, have recently contributed to the progression of photodynamic therapy (PDT) and microbial photodynamic inactivation (PDI) in clinical applications. The most important challenges facing this field are the physicochemical properties of photosensitizers (PSs), optimal drug release profiles, and the photosensitivity of surrounding tissues. By further integration of nanotechnology with semisolid formulations, very promising pharmaceuticals have been generated against several dermatological diseases (PDT) and (antibiotic-resistant) pathogenic microorganisms (PDI). This review focuses on the different PSs and their associated semisolid formulations currently found in both the market and clinical trials that are used in PDT/PDI. Special emphasis is placed on the advantages that the semisolid formulations bring to drug delivery in PDI. Lastly, some potential considerations for improvement in this field are also discussed.

A new LED device used for photodynamic therapy in treatment of moderate to severe acne vulgaris

OBJECTIVE

This study investigated the efficacy and safety of a newly designed LED device used in photodiagnosis and photodynamic therapy of moderate to severe acne vulgaris in Chinese patients.

METHODS

Forty-six patients with moderate to severe facial acne showing high degrees of fluorescence by ultraviolet light examination were illuminated during ALA-PDT with two wavelengths of light (543-548 nm, and 630±6 nm, respectively) after 2 h of incubation with ALA. Each patient received treatment once every 30 days for two or three sessions. Two independent investigators assigned an acne severity score at baseline, one week after each treatment, as well as 4, 8, and 12 weeks after the completion of treatment. Adverse effects were recorded during and after each treatment. All patients rated their satisfaction with the results of treatment at a 12-week follow up visit.

RESULTS

The ALA-PDL treatment regimen showed an overall effectiveness rate of 89.13% (41/46 patients). Some degree of clinical efficacy was seen in 71.42%, 86.67%, and 95.83% of patients with grades IV, V, and VI acne, respectively, and the rate of clinical effectiveness increased with increasing acne severity. When compared with baseline scores, significant reductions in acne scores were obtained at 8, and 12 weeks after completion of treatment. Maximum efficacy was shown at the 12 week follow up. No severe adverse events were observed.

CONCLUSION

ALA-PDT administered with the newly designed LED device was an effective treatment for moderate to severe acne vulgaris, and side effects were mild and reversible.

Light-based therapies in acne treatment

The use of light and laser in the treatment of acne is increasing as these modalities are safe, effective, and associated with no or minimal complications when used appropriately. These light and laser sources are also being used in combination with pharmacological and/or physical measures to synergize their effects and optimize the therapeutic outcome. This review focuses on optical devices used in treating acne and serves to delineate the current application of various methods, including their utility and efficacy.

Prospective study of topical 5-aminolevulinic acid photodynamic therapy for the treatment of severe adolescent acne in Chinese patients

Acne vulgaris is one of the most common skin diseases in adolescents. In the present study, we aimed to evaluate the effectiveness and safety of topical 5-aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) for the treatment of severe acne in Chinese adolescent patients. Twenty-one Chinese adolescent patients aged 12-18 years with Pillsbury III-IV severe facial acne were treated with three courses of ALA-PDT. A 5% ALA lotion was applied topically for 60 min followed by irradiation with light-emitting diode light at 633 nm with a light intensity of 75-80 mW/cm(2) and a light dose of 90-96 J/cm(2) . Clinical assessment was conducted before and after each treatment, and at each follow-up session. The total effective rates were 85.71%, 90.48%, and 95.23% after the three PDT sessions, and at the 4- and 8-week follow ups, respectively. ALA-PDT is an effective treatment for severe adolescent acne vulgaris, and is associated with mild and reversible side-effects.

Treating cutaneous squamous cell carcinoma using 5-aminolevulinic acid polylactic-co-glycolic acid nanoparticle-mediated photodynamic therapy in a mouse model

Background

Squamous cell carcinoma (SCC) is a common skin cancer, and its treatment is still difficult. The aim of this study was to evaluate the effectiveness of nanoparticle (NP)-assisted 5-aminolevulinic acid (ALA) delivery for topical photodynamic therapy (PDT) of cutaneous SCC.

Materials and methods

Ultraviolet-induced cutaneous SCCs were established in hairless mice. ALA-loaded polylactic-co-glycolic acid (PLGA) NPs were prepared and characterized. The kinetics of ALA PLGA NP-induced protoporphyrin IX fluorescence in SCCs, therapeutic efficacy of ALA NP-mediated PDT, and immune responses were examined.

Results

PLGA NPs enhanced protoporphyrin IX production in SCC. ALA PLGA NP-mediated topical PDT was more effective than free ALA of the same concentration in treating cutaneous SCC.

Conclusion

PLGA NPs provide a promising strategy for delivering ALA in topical PDT of cutaneous SCC.

Emerging drugs for the treatment of acne

INTRODUCTION

Acne is the most common skin condition in the US. The mainstay of acne therapy includes: topical retinoids, topical antibiotics, benzoyl peroxide (BP), and oral isotretinoin for severe cases. Although these treatment options are highly effective they do have certain drawbacks. Current acne treatment regimens often require patients to use multiple medications, some of which may have irritating side effects. Furthermore, Propionibacterium acnes resistance to antibiotics has become an increasing problem due to the rise in antibiotic use.

AREAS COVERED

New therapies that have either been released onto the market or that are being developed include: adapalene-BP combination agent, dapsone 5% gel, minocycline foam, topical nitric oxide-releasing agent, cortexolone 17 α-propionate, and CIP isotretinoin. Some of these new therapies address the challenges faced with existing treatment options. For instance, the relatively new combination therapy, adapalene-BP, limits antibiotic resistance and also helps simplify treatment regimens. The newly developed topical nitric oxide-releasing agent also holds potential in limiting antibiotic resistance.

EXPERT OPINION

Many of the new therapies discussed in this paper are still in early stages of testing so it is difficult to predict their outlook; however, based on preliminary findings, these therapies seem to be promising.

Recent advances in acne pathogenesis: implications for therapy

Acne pathogenesis is a multifactorial process that occurs at the level of the pilosebaceous unit. While acne was previously perceived as an infectious disease, recent data have clarified it as an inflammatory process in which Propionibacterium acnes and innate immunity play critical roles in propagating abnormal hyperkeratinization and inflammation. Alterations in sebum composition, and increased sensitivity to androgens, also play roles in the inflammatory process. A stepwise approach to acne management utilizes topical agents for mild to moderate acne (topical retinoid as mainstay ± topical antibiotics) and escalation to oral agents for more resistant cases (oral antibiotics or hormonal agents in conjunction with a topical retinoid or oral isotretinoin alone for severe acne). Concerns over antibiotic resistance and the safety issues associated with isotretinoin have prompted further research into alternative medications and devices for the treatment of acne. Radiofrequency, laser, and light treatments have demonstrated modest improvement for inflammatory acne (with blue-light photodynamic therapy being the only US FDA-approved treatment). However, limitations in study design and patient follow-up render these modalities as adjuncts rather than standalone options. This review will update readers on the latest advancements in our understanding of acne pathogenesis and treatment, with emphasis on emerging treatment options that can help improve patient outcomes.

Comparison of 5-aminolevulinic acid photodynamic therapy and red light for treatment of photoaging

OBJECTIVE

The aim of this pilot study was to compare the efficacy of ALA-PDT and red light alone in the treatment of photoaging.

METHODS

A total of 14 adults with photoaging skin were recruited. ALA-PDT or red light alone was applied to the forearm extensor. Before and after treatment, the treated sites were examined by dermoscopy, the changes in straum corneum (SC) hydration, transepidermal water loss (TEWL), and the L*a*b* values were measured, and microscopic examination of collagens and elastins was performed.

RESULTS

After ALA-PDT or red light illumination, the appearance of photoaging lesions improved, SC hydration increased and TEWL decreased. These changes in the ALA-PDT group were more obvious than those in the red light group. No significant change was noticed in the L*a*b* values in both groups. The signs of typical solar elastosis damage were improved in both groups.

CONCLUSIONS

ALA-PDT showed better skin rejuvenation effect than red light alone.