The assessment of psychology, quality of life in acne patients and evaluation of ALA-PDT for moderate to severe acne

Ionic Liquid Pretreatment Enhances Skin Penetration of 5-Aminolevulinic Acid: A Promising Scheme for Photodynamic Therapy for Acne Vulgaris

Acne vulgaris is one of the most prevalent skin disorders; it affects up to 85% of adolescents and often persists into adulthood. Topical 5-aminolevulinic acid (ALA)-based photodynamic therapy (PDT) provides an alternative treatment for acne; however, its efficacy is greatly undermined by the limited skin permeability of ALA. Herein, biocompatible ionic liquids (ILs) based on aliphatic acid/choline were employed to enhance the dermal delivery of ALA, thereby improving the efficacy of PDT. In addition to the one-step delivery of ALA by utilizing ILs as carriers, a two-step strategy of pretreating the skin with blank ILs, followed by the administration of free ALA, was employed to test the IL-facilitated dermal delivery of ALA in vitro. The cumulative permeation of ALA through the excised rat skin after IL pretreatment was significantly greater than that in the untreated group, the 20% dimethyl sulfoxide (DMSO) penetration enhancer group, and the one-step group. The penetration efficiency was influenced by formulation and treatment factors, including the type of IL, pretreatment duration, water content in the ILs, and concentration of ALA. In rats, IL pretreatment facilitated faster, greater, and deeper ALA-induced protoporphyrin IX (PpIX) accumulation. Moreover, the IL pretreatment regimen significantly improved the efficacy of ALA-based PDT against acne vulgaris in a rat ear model. The model IL choline citrate ([Ch]3[Cit]1) had a moderate effect on the skin barrier. Trans-epidermal water loss could be recovered 1 h after IL treatment, but no irritation to the rat skin was detected after 7 days of consecutive treatment. It was concluded that biocompatible IL pretreatment enhances the penetration of ALA and thus facilitates the transformation of PpIX and improves the efficacy of PDT against acne vulgaris.

The mechanism and application of computer-assisted full facial skin imaging systems

Computer-assisted full facial imaging systems are currently among the most widely used skin analysis instruments in dermatology and medical cosmetology. These systems offer objective quantitative evaluation of facial skin conditions, and as they are non-invasive, play an important role in assessing dermatological conditions such as pigmentation, inflammation, vascular diseases, skin texture, the severity of ageing, and therapeutic follow-up. Although computer-assisted full facial imaging systems enable quantitative analysis in the scope of medical treatment and cosmetic evaluation, their results may considerably vary because of the influence of environmental and postural factors for improper operation. Furthermore, manual observation is sometimes necessary for experimental work for more accuracy, and familiarity with the imaging principles and application points is necessary to best apply this technique. This report aims to discuss and interpret these systems' imaging mechanisms and explore the primary issues with their application.

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.

Sonophoresis enhances the skin penetration of 5-aminolevulinic acid: A promising pretreatment for photodynamic therapy

5-aminolevulinic acid (5-ALA) has a poor penetrance of the skin with topical application, which reduces the efficacy of photodynamic therapy (PDT). Sonophoresis involves the use of sound waves or ultrasonic energy to enhance the topical or transdermal delivery of drugs. The purpose of this study was to investigate the effects of sonophoresis on the penetration of 5-ALA into the skin. We calculated in vitro transdermal accumulation of ALA, and the fluorescence images were collected for analysis. The cumulative amount of 5-ALA that penetrated the skin with sonophoresis increased over time and was significantly larger than that without sonophoresis (p < 0.01). With 5% 5-ALA and sonophoresis, the distinct localization of 5-ALA-PpIX in sebaceous glands started to appear 30 min after 5-ALA application, which is much earlier than with 5% 5-ALA only. For all incubation times, fluorescence intensities distributing in sebaceous glands were significantly higher in sonophoresis treated than non-sonophoresis treated skin (p < 0.05). Sonophoresis could be a technique of choice for enhancing the production of 5-ALA-induced PpIX and improving the efficacy of 5-ALA-based PDT, which may decrease the treatment time, lower the cost of therapy and enhance the clinical improvement, allowing many more patients to be treated.

A new natural detector for irradiations with blue LED light source in photodynamic therapy measurements via UV-Vis spectroscopy

Photodynamic therapy has been recently studied, bringing innovations regarding the reduction of exposure time to light by the patient. This work aimed to investigate the feasibility of using Coutarea hexandra (Jacq.) K. Schum (CHS) as a detector in photodynamic therapy measurements. For this, an irradiator containing a blue LED bulb lamp was utilized. The CHS samples were irradiated with ten doses from 0.60 up to 6.0 kJ/cm², and six concentrations were prepared (1, 2, 3, 4, 5, and 6 mg/ml) for the CHS detector samples. After irradiation, the detector samples were evaluated using UV-Vis spectrophotometry. The results showed the behavior of the CHS detector with doses and concentrations, its sensitivity, and its linearity was also evaluated both by Wavelength Method (WM) and the Kernel Principal Component Regression (KPCR) Statistical Method. The values obtained indicate that this method can be applied to the CHS sample detector. In conclusion, the CHS is a promising detector in the field of photodynamic therapy.