Topical ALA-Photodynamic Therapy for Acne Can Induce Apoptosis of Sebocytes and Down-regulate Their TLR-2 and TLR-4 Expression

Acne-induced pathological scars: pathophysiology and current treatments

Acne is a common chronic inflammatory dermatosis that can lead to pathological scars (PSs, divided into hypertrophic scars and keloids). These kinds of abnormal scars seriously reduce the quality of life of patients. However, their mechanism is still unclear, resulting in difficult clinical prevention, unstable treatment effects and a high risk of recurrence. Available evidence supports inflammatory changes caused by infection as one of the keys to abnormal proliferation of skin fibroblasts. In acne-induced PSs, increasing knowledge of the immunopathology indicates that inflammatory cells directly secrete growth factors to activate fibroblasts and release pro-inflammatory factors to promote the formation of PSs. T helper cells contribute to PSs via the secretion of interleukin (IL)-4 and IL-13, the pro-inflammatory factors; while regulatory T cells have anti-inflammatory effects, secrete IL-10 and prostaglandin E2, and suppress fibrosis production. Several treatments are available, but there is a lack of combination regimens to target different aspects of acne-induced PSs. Overall, this review indicates that the joint involvement of inflammatory response and fibrosis plays a crucial role in acne-induced PSs, and also analyzes the interaction of current treatments for acne and PS.

A prospective, split-face, randomized controlled trial of intense pulsed light-photodynamic therapy for seborrhea

BACKGROUND

Seborrhea poses a common cosmetic concern in adolescents and young adults, often accompanied by enlarged pores, and contributing to various skin conditions, including acne vulgaris and seborrheic dermatitis. At present, there is a lack of effective treatment for this problem, and the potential of photodynamic therapy (PDT) in reducing sebum remains inconclusive.

OBJECTIVE

This exploratory, prospective, single-center, double-blinded, randomized split-face controlled trial aimed to compare the efficacy and safety of intense pulsed light-photodynamic therapy (IPL-PDT) versus IPL therapy for seborrhea.

METHODS

Participants with seborrhea underwent 3 times of IPL treatment (590 nm, 15-17 J/cm2 based on patient's tolerance) for one hemifacial part and IPL-PDT treatment for the other. Follow-up assessment was conducted up to 8 weeks after the final treatment.

RESULTS

Compared with single IPL treatment, IPL-PDT can significantly inhibit sebum secretion and decrease pore size. PDT group exhibited no additional damage to the skin barrier, with even lower transepidermal water loss (TEWL). Additionally, the PDT group showed superior improvement in scores of porphyrins, red areas, and ultraviolet (UV) spots. Both groups experienced only mild topical adverse effects, well tolerated by the participants.

CONCLUSION

IPL-PDT is a more effective method than IPL in the treatment of seborrhea, as well as on the improvement of the skin barrier function.

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.

Effect of various types of photodynamic therapy on inflammatory and non-inflammatory lesions in patients with acne: A network meta-analysis of randomized controlled trials

BACKGROUND

Recent studies have demonstrated that photodynamic therapy (PDT) is safe and effective in treating acne vulgaris. The present study aimed to evaluate various PDTs on inflammatory and non-inflammatory lesions in patients with acne by a network meta-analysis (NMA) of randomized controlled trials (RCTs).

METHODS

The researchers of this paper searched PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases from inception to March 2022 to identify suitable RCTs. The included studies were evaluated for methodological quality using the Cochrane bias risk assessment tool. Twenty-one RCTs were included, with a total sample size of 898 participants.

RESULTS

Network meta-analysis (NMA) revealed that indocyanine green (ICG) + near-infrared (NIR) diode laser, ICG+830 nm light-emitting diode (LED), indole-3-acetic acid (IAA) + 520 nm LED, and 5-aminolevulinic acid (ALA) + sunlight demonstrated obvious curative effects in patients with acne vulgaris. Importantly, ICG+NIR diode laser provided the greatest improvement in both inflammatory and non-inflammatory acne lesions (surface under the cumulative ranking curve [SUCRA]: 84.4% and 93.5%, respectively).

CONCLUSIONS

Based on the NWM and SUCRA ranking, ICG + NIR diode laser can be considered more effective in treating acne than the other PDTs of the RCTs. However, this conclusion should be interpreted with caution due to the limitations of the present study.

ALA-PDT augments intense inflammation in the treatment of acne vulgaris by COX2/TREM1 mediated M1 macrophage polarization

Severe acne vulgaris is a common chronic inflammatory skin disease worldwide. 5-Aminolaevulinic acid photodynamic therapy (ALA-PDT) is effective and safe for severe acne. However, the mechanism is not fully understood. Intense acute inflammatory response at 24 h after ALA-PDT is reported positively correlated to the effectiveness. Inflammation regulation influence the progression or outcome of diseases. ALA-PDT may exert its therapeutic effect by augmenting intense inflammation and break the chronic inflammation. This study was set out to explore the mechanism of ALA-PDT augmenting intense acute inflammation in the treatment of acne. As a result, transcriptome microarrays analysis of severe acne patients showed that ALA-PDT significantly up-regulated expression of various inflammation-related genes, especially TREM1 and PTGS2, which were further confirmed by a C.acnes induced acne-like mouse ear model. The subsequent experiments demonstrated that ALA-PDT could trigger pro-inflammatory M1 polarization of macrophages in vitro and in vivo. Additionally, the crosstalk between keratinocytes and macrophages studied by a transwell co-culture system indicated that PGE2 secreted by ALA-PDT treated HaCaT cells could promote THP-1 macrophages M1 polarization by COX2/PGE2/TLR4/TREM1 axis to augment inflammation. Our study provides a novel insight that ALA-PDT could amplify inflammation by COX2/TREM1 mediated macrophages M1 polarization for the treatment of acne. It is hoped that this research will decipher the mechanism of ALA-PDT for the treatment of acne and provide a theoretical basis for optimizing the clinical ALA-PDT management.

The Role of Skin Immune System in Acne

Acne vulgaris is a skin disease that often occurs in adolescence and in young adulthood. The main pathogenic factors are hyperkeratinization, obstruction of sebaceous glands, stimulation of sebaceous gland secretion by androgens, and bacterial colonization of sebaceous units by Cutibacterium acnes, which promotes inflammation. Little is known about the role of skin immune cells in the development of acne lesions. The aim of the study was to try to understand the role of skin immune cells in the course of acne. Recent studies have shown that there are at least four major pathways by which Cutibacterium acnes interacts with the innate immune system to induce inflammation: through TLRs, activating inflammasomes, inducing the production of matrix metalloproteinases (MMPs), and stimulating antimicrobial peptide (AMP) activity. Cells of adaptive immune response, mainly Th1 and Th17 lymphocytes, also play an important role in the pathogenesis of acne. It is worth emphasizing that understanding the role of the skin’s immune cells in the pathogenesis of acne may, in the future, contribute to the application of modern therapeutic strategies that would avoid addiction to antibiotics, which would alleviate the spectrum of resistance that is now evident and a current threat.

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.

Photodynamic Therapy with 5-aminolevulinic Acid 10% Gel and Red Light for the Treatment of Actinic Keratosis, Nonmelanoma Skin Cancers, and Acne: Current Evidence and Best Practices

Photodynamic therapy (PDT) can be an effective treatment for actinic keratosis (AK) as well as selected non-melanoma skin cancers (NMSCs), such as Bowen's disease and superficial basal cell carcinoma. PDT has also demonstrated effectiveness in the management of acne vulgaris. Results from controlled clinical trials have shown the safety and efficacy of PDT for these conditions with the use of different photosensitizers and a wide range of light sources. PDT has been employed effectively as monotherapy and in combination with other topicals and alternate light or laser energy therapies. This article provides expert practical guidance for the use of the newest 5-aminolevulinic acid (ALA) product (ALA 10% gel) plus red light as monotherapy for AKs, NMSC, and acne. Here, information from clinical guidelines and a summary of supporting evidence is provided for each cutaneous condition. The authors also provide detailed guidance for employing ALA 10% gel, a photosensitizer precursor, for each of these applications.

5-Aminolaevulinic acid photodynamic therapy suppresses lipid secretion of primary sebocytes through AMPK/SREBP-1 pathway

BACKGROUND

Acne vulgaris is a chronic inflammatory skin disease around pilosebaceous unit. 5-Aminolaevulinic acid photodynamic therapy (ALA-PDT) is an effective therapy for severe acne vulgaris. However, its specific treatment mechanism remains unclear. In the present study, we investigated the potential mechanism of how ALA-PDT induced lipid secretion inhibition in acne vulgaris.

METHODS

Primary human sebocytes and sebaceous gland of golden hamster were treated with/without ALA-PDT. Cell viability was evaluated by Live/Dead Cell assay. Fluorescence microscope was used to observe lipids secretion in sebocytes after Nile red staining. The expression of SREBP-1 after ALA-PDT was evaluated by qRT-PCR. Regulation of ALA-PDT on AMPK/SREBP-1 was evaluated by western blot.

RESULTS

The results showed that ALA-PDT suppressed lipid secretion of primary human sebocytes. In addition, ALA-PDT could inhibit the expression of SREBP-1 in vitro. We also found that ALA-PDT activated AMPK pathway, down-regulating the expression of SREBP-1 in sebocytes after ALA-PDT.

CONCLUSIONS

These findings elucidate that ALA-PDT suppresses lipid secretion through AMPK/SREBP-1 pathway in treatment of acne vulgaris.

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.

Comparison of efficacy of aminolaevulinic acid photodynamic therapy vs. adapalene gel plus oral doxycycline for treatment of moderate acne vulgaris-A simple, blind, randomized, and controlled trial

BACKGROUND

Although progress has been made in the study of photodynamic therapy for acne, studies using current recommended therapies as active comparators are lacking.

METHODS

Randomized, controlled trial involving 46 patients with moderate inflammatory facial acne, 23 patients received two sessions of PDT separated by 2 weeks (ALA 20% incubated 1.5 hours before red light irradiation with 37 J/cm² fluence) and 23 patients received doxycycline 100 mg/d plus adapalene gel 0.1%. In both groups, from the sixth week, we started adapalene gel 0.1% as maintenance therapy until 12 weeks of follow-up. Primary end point was the reduction of acne lesions at the 6-week follow-up, which was evaluated by 2 investigators blinded to the intervention.

RESULTS

The median percent reductions in noninflammatory lesion count (P = 0.013) and total lesions (P = 0.038) at 6 weeks was found to be significantly higher in the group receiving PDT. At 12 weeks there was a greater reduction of inflammatory lesions in PDT group with 84% vs. 74% for group who received doxycycline plus adapalene (P = 0.020) as well as in reducing total lesions with 79% vs. 67% respectively (P = 0.026). No severe side-effects were observed for either therapy.

CONCLUSIONS

ALA-PDT offers promise as an alternative treatment for moderately severe inflammatory acne that has a higher effectiveness than the combination of doxycycline and adapalene gel in reducing noninflammatory and total lesions at 6 weeks. There were significantly superior reductions at 12 weeks in the combination of PDT group followed by adapalene gel in total, inflammatory, and noninflammatory lesions.

The efficacy and tolerability of 5-aminolevulinic acid 5% thermosetting gel photodynamic therapy (PDT) in the treatment of mild-to-moderate acne vulgaris. A two-center, prospective assessor-blinded, proof-of-concept study

BACKGROUND

Acne vulgaris is a chronic inflammatory skin disease, commonly treated with topical or systemic drugs, according to the severity of the condition. Retinoids and antibiotic compounds are considered cornerstone approaches in this condition. However, low adherence to the therapy and the issue of bacterial resistance undermine the efficacy in the long term. Photodynamic therapy (PDT) with 20% aminolevulinic acid (ALA) has shown to be effective in the treatment of inflammatory acne. Skin tolerability, however, could be a limiting factor for a widespread use of this approach. A new formulation of 5% ALA in thermosetting gel has been recently available. This formulation allows a more convenient application procedure without occlusion and better and more efficient release of the active compound in comparison with traditional ALA formulations like creams or ointments.

STUDY AIM

To evaluate in a two-center, assessor-blinded, prospective, proof-of-concept study, the efficacy, and tolerability of red-light (630 nm) PDT with a new 5-ALA "low-dose" topical gel formulation (5%) in the treatment of inflammatory mild-to-moderate acne vulgaris (AV).

SUBJECTS AND METHODS

A total of 35 subjects with moderate AV of the face (mean age: 24 ± 8 years, 13 men and 22 women) were enrolled, after their written informed consent. The primary outcome was the evolution of GAG (Global Acne Grade System) score at baseline and after an average of three, 630-nm, 15-minute, PDT sessions, performed every 2 weeks. GAG score was also calculated in a follow-up visit 6 months after the last PDT session. Skin tolerability was assessed during PDT sessions with a patient-reported discomfort level evaluation score from 0 (no discomfort at all) to 3 (severe discomfort).

RESULTS

At baseline, the GAG score was 21 ± 6. After the last PDT session, the GAG score evaluated in a blinded fashion (digital photographs) was significantly reduced to 6.5 ± 5.7, representing a 70% reduction (P = .0001, Wilcoxon test; mean difference 14.9; 95% CI of the difference: 12.1-17.6). At the follow-up visit, the GAG score was 6.7 ± 6.8. The 5% ALA thermosetting gel Red-light PDT was in general very well tolerated with a discomfort mean level score of 0.5 ± 1.

CONCLUSION

This proof-of-concept study supports the efficacy of 5% ALA thermosetting gel red-light PDT in inflammatory acne of the face with a relevant clinical improvement of inflammatory lesions with a very good tolerability profile. Clinical improvement was maintained in the medium term (Trial Registration Number: ISRCTN66066651).

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.

5-aminolevulinic acid mediated photodynamic therapy inhibits survival activity and promotes apoptosis of A375 and A431 cells

OBJECTIVES

The purpose of this study was to investigate the effects of 5-aminolaevulinic acid mediated photodynamic therapy (ALA-PDT) on the survival activity and apoptosis of human melanoma cell line A375 and non-melanoma skin carcinoma cell line A431 cells. The mechanism for cellular apoptosis was explored.

METHODS

The cell survival activity was determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and the proportion of apoptotic cells was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The expression levels of Bcl-2, Bax, caspase-3, caspase-8 and caspase-9 protein were assessed by western blot. The subcellular localization of cytochrome c was comparatively investigated by immunohistochemistry between pre-ALA-PDT and post- ALA-PDT.

RESULTS

ALA-PDT significantly inhibited the survival activity of A375 cells and A431 cells in a dose- and time-dependent manner. The optimum inhibition efficiencies for A375 cells and A431 cells were obtained at 0.6 mM ALA at 4 h and 8 h after ALA-PDT, respectively. The phenomena of apoptosis were observed in ALA-PDT treated cells by TUNEL assay. The apoptotic rates of A375 cells and A431 cells were 90.0% and 61.5% at 6 h after ALA-PDT, respectively. Apoptosis induced by ALA-PDT involved in down-regulation of Bcl-2 protein, up-regulation of Bax protein and cleaved-PARP protein. It was observed that the expression of cleaved- caspase-3, caspase-8 and caspase-9 proteins in A375 cells and A431 cells gradually increased in 2 h and 4 h but decreased at 4-6 h and 6-8 h after ALA-PDT, respectively. In apoptosis cells immunohistochemical localization show that cytochrome C diffused from the mitochondria into the cytosol.

CONCLUSION

ALA-PDT could significantly inhibit the survival activity of A375 and A431 cells. The apoptosis induced by ALA-PDT in A375 and A431 cells was related to the caspase-dependent death-receptor pathway and Cytochrome c-dependent mitochondrial pathway.

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.

Efficacy of a Complex of 5-Aminolevulinic Acid and Glycyl-Histidyl-Lysine Peptide on Hair Growth

BACKGROUND

Pattern hair loss is a very common problem. Although effective therapeutics for the treatment of pattern hair loss have been used, novel therapeutic modalities are still required to enhance hair growth.

OBJECTIVE

We investigated the efficacy and safety of a complex (ALAVAX) of 5-aminolevulinic acid (5-ALA) and glycyl-histidyl-lysine (GHK) peptide for the treatment of pattern hair loss.

METHODS

Forty-five patients with male pattern hair loss were treated with ALAVAX 100 mg/ml (group A), ALAVAX 50 mg/ml (group B) or placebo (group C) once a day for 6 months. Total hair count, hair length, hair thickness, patient's assessment and adverse events were evaluated at month 1, 3, and 6.

RESULTS

An increase in hair count for 6 months was 52.6 (p<0.05) in group A, 71.5 (p<0.05) in group B, and 9.6 in group C. The ratio of changes in hair count between group B (2.38) and group C (1.21) at 6 months showed a statistically significant difference (p<0.05). The proportion above good satisfaction was higher in group A (26.7%) than in the other groups (group B: 14.3%, group C: 7.1%). There was no statistically significant difference in hair length and hair thickness among 3 groups at 6 months. There was no adverse event in 3 groups.

CONCLUSION

Our study showed that a complex of 5-ALA and GHK peptide may be considered as one of the complementary agents for the treatment of male pattern hair loss.

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.

Multiple sequential light and laser sources to activate aminolevulinic acid for rosacea

BACKGROUND AND AIMS

The use of multiple, sequential light and laser sources for topical ALA activation in photodynamic therapy (PDT) of rosacea has been largely absent from the literature. The aim of this study was to evaluate ALA-PDT for rosacea using blue light sequentially with red light, pulsed-dye laser (PDL), and/or intense pulsed light (IPL).

PATIENTS/METHODS

Thirty patients (39 treatments) were enrolled in this retrospective, single-center study. Treatment groups included blue light + PDL, blue light + IPL, blue light + PDL + IPL, or blue light + red light + PDL + IPL. Patient-reported outcome measures (incidence of adverse events, improvement in rosacea, and improvement in overall skin quality) were obtained via a telephone questionnaire and graded on a 4-point scale.

RESULTS

There was no statistically significant difference in patient-reported rosacea or overall skin quality improvement. Apart from decreased peeling following blue light + IPL compared to blue light + PDL (P = 0.041) and blue light + IPL + PDL (P = 0.005), there were no other statistically significant differences in postprocedure adverse events.

CONCLUSIONS

The use of multiple, sequential light and laser sources with ALA-PDT for rosacea, while well tolerated, did not lead to statistically significant improvements in patient-reported efficacy. Although this retrospective study is limited by a small sample size with disparate patient numbers between groups and no physician-evaluated outcome criteria, it does demonstrate that multiple light sources with PDT can be safely used in a single session.

Use of Optical Fiber Imported Intra-Tissue Photodynamic Therapy for Treatment of Moderate to Severe Acne Vulgaris

Background

To treat moderate to severe acne vulgaris, we developed an optical fiber imported intra-tissue photodynamic therapy: the optical fiber irradiation 5-aminolevulinic acid photodynamic therapy (OFI-ALA-PDT). The aim of this study was to compare the treatment effect and tolerability of OFI-ALA-PDT versus traditional ALA-PDT in the treatment of moderate to severe acne vulgaris.

Material/Methods

60 patients with facial acne enrolled into this study were randomly divided into an OFI-ALA-PDT group and a traditional ALA-PDT group, with 30 patients in each group. The difference between these 2 groups was the red light irradiation methods used. In the OFI-ALA-PDT group we used intra-tissue irradiation (import the red light directly into the target lesion with optical fiber) for 5 min, while the traditional ALA-PDT group received whole-face irradiation for 20 min. All patients received 1 irradiation every 7 to 10 days for a total of 6 irradiations. Treatment effects and adverse reactions were recorded after the 4^th and 6^th irradiation, and at 4, 8, 16 weeks after the entire treatment.

Results

After the 4^th irradiation, significantly different effective rates were observed in these groups (90.0% for the OFI-ALA-PDT group and 66.7% for the control group). However, no significant difference in effective rate was recorded in the later observations. There were 182 adverse reactions in the OFI-ALA-PDT group and 497 in the control group, which showed a significant difference (P<0.05).

Conclusions

OFI-ALA-PDT showed improved treatment effective rate in the early stage of irradiation, and it had fewer adverse reactions.

Daylight photodynamic therapy with 1.5% 3-butenyl 5-aminolevulinate gel as a convenient, effective and safe therapy in acne treatment: A double-blind randomized controlled trial

While daylight photodynamic therapy (PDT) is a simpler and more tolerable treatment procedure for both clinicians and patients, it has never been applied for acne treatment. In this study, we evaluated efficacy, safety and histological changes of facial acne after application of the novel variant of 5-aminolevulinate (ALA)-ester, 1.5% 3-butenyl ALA-bu gel, using daylight only as the potential visible light source. Forty-six acne patients were randomly assigned to either ALA-bu or vehicle application group in a double-blind fashion. Both groups applied the allocated gel to facial acne lesions every other day for 12 weeks. At the final 12 week, both inflammatory and non-inflammatory acne lesions had decreased significantly by 58.0% and 34.1% in the ALA-bu group, respectively. Only a few patients expressed mild adverse effects. In the histopathological analysis, attenuated inflammatory cell infiltrations were observed and immunostaining intensities for interleukin-8, interleukin-1β, matrix metalloproteinase-9 and phosphorylated nuclear factor-κB were reduced concomitantly. Changes of their mRNA expression demonstrated comparable patterns. In conclusion, this ambulatory PDT was effective, very well tolerated and convenient for treating inflammatory acne lesions. Experimental results correlated well with clinical results. This novel regimen would provide a viable option for acne therapy.

Inflammatory Cytokine Expression and Sebum Production after Exposure of Cultured Human Sebocytes to Ultraviolet A Radiation and Light at Wavelengths of 650 nm and 830 nm

BACKGROUND

The effectiveness of ultraviolet (UV) radiation, visible light, or infrared light therapy for the treatment of acne is the subject of ongoing scientific debate.

OBJECTIVE

This study was conducted to investigate changes in sebum production and the expression of inflammatory cytokines, matrix metalloproteinases (MMPs), and antimicrobial peptides (AMPs), following exposure of cultured human sebocytes to UVA radiation and light at wavelengths of 650 nm and 830 nm.

METHODS

Reverse transcription polymerase chain reaction assays were performed to measure the gene expression levels of inflammatory cytokines (interleukin [IL]-1β, IL-6, IL-8, and tumor necrosis factor-α), MMPs (MMP-1, MMP-3, and MMP-9), and AMPs (psoriasin, hBD-2, hBD-3, and LL-37) in cultured sebocytes after exposure to UVA radiation (2 J/cm(2), 3 J/cm(2), and 5 J/cm(2)) and light at wavelengths of 650 nm (14 J/cm(2), 29 J/cm(2), and 87 J/cm(2)) and 830 nm (5 J/cm(2), 10 J/cm(2), and 30 J/cm(2)). Expression of inflammatory cytokine proteins and sebum production were measured using enzyme-linked immunoassays and a lipid analysis kit, respectively.

RESULTS

Exposure of cultured sebocytes to UVA radiation and light at wavelengths of 650 nm and 830 nm did not show a significant increase in the expression of inflammatory cytokines, MMPs, or AMPs. Sebum production was not significantly decreased after exposure to UVA radiation and light at both wavelengths.

CONCLUSION

We propose that UVA radiation, visible light, and infrared light can be used to target Propionibacterium acnes for the treatment of acne, without an increase in the expression of inflammatory biomarkers and sebum production.

The process of apoptosis in a holocrine gland as shown by the avian uropygial gland

This study was designed to elucidate the presence of apoptosis and the localization of apoptosis-related Bax and survivin proteins and proliferating cell nuclear antigen (PCNA) within the chicken uropygial gland, a specialized holocrine secretory gland. In day-old chicks, survivin and Bax immunoreactivities were observed in the cell cytoplasm of the germinative and secretory layers of the luminal epithelium and tubules. During this period, the TUNEL reaction, an indication of apoptosis, was only sporadically positive in the tubules. From the 7th day to the 150th day of posthatching, survivin was detected in the cytoplasm of cells in the germinative layer and in the nuclei of some cells in the secretory layers of the gland. The germinative layer cells showed weak homogeneous cytoplasmic staining for Bax, whereas the cells of the secretory and intermediate layers of luminal epithelium and tubules exhibited granular cytoplasmic staining. After day 7, TUNEL-positive cells were observed in the secretory and degenerative layers of the luminal epithelium and central tubules. After day 12, some TUNEL-positive cells were also seen in the peripheral tubules. At all posthatch ages, the cytoplasm and nucleus of the germinative layers of luminal epithelium and tubules reacted with PCNA, whereas only a small number of cell nuclei in the secretory layers were immunopositive. These results support the theory that specific PCNA/Bax/survivin expression patterns could reflect particular cell differentiation states in the uropygial gland and that holocrine secretion in the gland is realized mainly by way of apoptosis.

Photodynamic sensitivity of esophageal cancer KYSE-70 cells is attenuated by all-trans retinoic acid-induced differentiation

AIM: To investigate the impact of all-trans retinoic acid (ATRA)-induced cell differentiation on photodynamic sensitivity of human esophageal cancer cell line KYSE-70.

METHODS: Both well and poorly differentiated KYSE-450 cell lines were used in this study. KYSE-70 differentiation was induced with 1 µmol/L ATRA and evidenced by cell morphology and proliferation. Phototoxicity after photodynamic therapy (PDT, 450 nm) was detected by MTT assay. Apoptosis was measured by flow cytometry, and morphology of apoptotic cells was visualized after Hoechst 33342 staining.

RESULTS: Cells after ATRA treatment exhibited increased size, reduced cytoplasmic and nuclear density, and nuclear enlargement. Cell growth was inhibited compared to control cells. After PDT treatment, the survival of well differentiated KYSE-450 cells and ATRA-treated KYSE-70 cells were reduced compared to poorly differentiated KYSE-70 cells. Cell viability differed significantly between ATRA-treated and non-treated KYSE-70 cells after PDT treatment (54.28% ± 3.64% vs 36.23% ± 7.43%, P < 0.001). The percentage of apoptotic cells in ATRA-induced KYSE-70 cells was less than that in non-treated KYSE-70 cells (18.1% vs 33.3%, P < 0.05).

CONCLUSION: ATRA-induced cell differentiation decreases photodynamic sensitivity of esophageal cancer KYSE-70 cells possibly by inducing resistance to apoptosis.