Photodermatology, photoimmunology & photomedicine最新文献

Aim: This study aimed to explore the underlying mechanism of theacrine treatment of UV-induced skin photodamage.

Materials and methods: Tandem Mass Tag (TMT) relative quantitative proteomics analysis was used to characterize the proteins and pathways associated with the ability of theacrine to combat photodamage in mouse skin by modeling UV irradiation of the backs of ICR mice.

Results: Apoptosis-related proteins and signaling pathways play a key role in the ability of theacrine to protect against skin photodamage, according to proteomic and bioinformatics analysis; molecular docking and Western blotting further revealed that theacrine was associated with apoptosis-related proteins (p53, Bcl-2, Bax, caspase-3, and cleaved-caspase-3) with strong binding affinity, which can significantly reduce skin cell apoptosis induced by UV exposure.

Conclusion: The findings revealed that theacrine can reduce UVB-induced epidermal damage by controlling the apoptosis signaling pathway, implying that theacrine could be a useful anti-UVB damage agent.

Background: Photopatch testing represents the gold standard for the diagnosis of photoallergic contact dermatitis (PACD). We aimed to identify common photoallergens in our tertiary dermatological referral centre from 2012 to 2021, to compare this to the preceding period studied, and data from other communities.

Methods: We conducted a retrospective review of all 90 patients who underwent photopatch testing at the National Skin Centre, Singapore, between 2012 and 2021.

Results: Of 90 patients, 19 (21.1%) were male, and the mean age was 41.6 years. Eighty-four (93.3%) underwent testing to our standard sunscreen series, 10 (11.1%) to our extended series, and 73 (81.1%) to their own items. Seventeen (18.9%) were diagnosed with PACD (i.e., photocontact allergy with present or past relevance), 12 (13.3%) with ACD, and 4 (4.4%) with photoaugmented ACD. Relevant reactions were commonest to oxybenzone (8, 9.5%) and mexenone (3, 3.6%). Eleven (15.1%) had PACD to their own items, with 3 of 4 (75%) tested to ketoprofen diagnosed with PACD and the remaining 1 (25%) with photoaugmented ACD. Age, race, sex, atopy, and site of involvement were not associated with photocontact allergy. Compared to the preceding time period, the overall frequency of photocontact allergy and PACD decreased, but rates of photoallergic reactions to individual photoallergens were not significantly different.

Conclusion: Organic ultraviolet absorbers such as oxybenzone and mexenone remained the most relevant photoallergens. Personal item testing was valuable, and testing to ketoprofen should be considered.

Background/purpose: Riehl's melanosis is a difficult-to-treat condition characterized by persisting dermal hyperpigmentation. This study aimed to evaluate the efficacy of a histology-specific targeted therapy for Riehl's melanosis.

Methods: Skin biopsy samples of Riehl's melanosis were assessed to identify histology-specific targets for treatment. Subsequently, the efficacy of a combination involving a fractional picosecond laser and a pulsed dye laser (PDL) targeting the dermal melanin and vessels, respectively, was evaluated. Clinical improvement was assessed using the dermal pigmentation area and severity index (DPASI). The treatment outcomes were compared to those of a control, in this case a single laser treatment solely targeting pigmentation.

Results: Histological and immunohistochemical analyses identified dermal melanin pigment and dilated vessels as treatment targets for Riehl's melanosis. The combined treatment of the fractional picosecond laser and PDL showed a significant reduction of the DPASI scores, which was significantly better than the control group. Patients who underwent the combined laser treatment indicated high levels of satisfaction with no adverse events except of transient erythema and oedema.

Conclusion: The combined treatment of a fractional picosecond laser and a PDL was more effective for Riehl's melanosis compared to single laser treatment. The treatment targets both dermal pigmentation and dilated vessels, offering promising results for those working to manage Riehl's melanosis.

Background: We previously reported that the level of mitochondrial ubiquitin ligase (MITOL) protein in fibroblasts was decreased by UVA and that the knock-down (KD) of MITOL increased the secretion of matrix metalloprotease-1 (MMP-1) by fibroblasts. A recent study reported that MITOL suppresses endoplasmic reticulum (ER) stress by stabilizing the interaction between ER and mitochondria (MT) through the ubiquitination of mitofusin 2. These facts suggest that a decrease of MITOL would increase the secretion of MMP-1 through ER stress, but the detailed mechanism of that process in dermal fibroblasts remains unclear. Thus, this study was conducted to clarify the involvement of ER stress in the oversecretion of MMP-1 induced by the decreased MT quality caused by MITOL-KD.

Methods: MITOL-KD normal human dermal fibroblast (NHDFs) were prepared by treating them with MITOL-small interfering RNA, after which their MMP-1 protein levels were measured. ER stress in NHDFs was evaluated by measuring the mRNA levels of spliced X-box binding protein 1 (sXBP1) and the protein levels of inositol-requiring enzyme 1α (IRE1α).

Results: MITOL-KD NHDFs enhanced the secretion of MMP-1 via interleukin-6 (IL-6) elicited by the activation of nuclear factor-kappa B (NF-κB). The secretion of MMP-1 could be abrogated by a neutralizing IL-6 antibody and by JSH23, which is an inhibitor of NF-κB activation. Furthermore, MITOL-KD NHDFs as well as UVA-irradiated NHDFs showed increased ER stress levels. In addition, tunicamycin, which is an inducer of ER stress, also increased MMP-1 secretion.

Conclusion: These results suggested that the decrease of MITOL caused the oversecretion of MMP-1 via NF-κB-IL-6 signaling through the activation of ER stress in fibroblasts.

Background: Infrared radiation (IR) is the portion of the electromagnetic spectrum between visible light (VL) and microwaves, with wavelengths between 700 nm and 1 mm. Humans are mainly exposed to ultraviolet (UV) radiation (UVR) and IR through the sun. Unlike UVR which is well known for its carcinogenic properties, the relationship between IR and skin health has not been as extensively studied; as such, we gather the available published evidence here to better elucidate this relationship.

Methods: Several databases including Pubmed, Google Scholar, and Embase were searched for articles relating to infrared radiation and the skin. Articles were selected for their relevance and novelty.

Results: Detrimental effects such as thermal burns, photocarcinogenesis, and photoaging have been reported, though evidence suggests that these may be due to the thermal effects produced secondary to IR exposure rather than the isolated effect of IR. There are currently no chemical or physical filters specifically available for protection against IR, and existing compounds are not known to have IR-filtering capacity. Interestingly, IR may have some photoprotective properties against the carcinogenic effects of UVR. Furthermore, IR has been used with encouraging results in skin rejuvenation, wound healing, and hair restoration when given at an appropriate therapeutic dose.

Conclusion: A better understanding of the current landscape of research surrounding IR can help illuminate its effects on the skin and highlight areas for further research. Here, we review relevant data on IR to assess its deleterious and beneficial effects on human skin, along with possible means for IR photoprotection.

Background: Hemoporfin-mediated photodynamic therapy (HMME-PDT) is currently considered one of the most promising therapies for port-wine stain (PWS). However, the efficacy of this is very variable and needs further studies.

Methods: A total of 101 patients with PWS in the face, neck, or extremities who received at least 2 HMME-PDT sessions were included in the study, and correlations of efficacy with age, gender, locations, treatment sessions, and PDL treatment history were analyzed.

Results: The efficacy of HMME-PDT in patients with different ages, locations, and different numbers of prior PDL treatment showed constantly significant differences after 1/2/last session (p < .05). The number of treatments was associated with efficacy, and patients who received more than two sessions had a better response than those who underwent two sessions only (p < .001). Ordinal logistic regression analysis confirmed the above-mentioned associations. Nevertheless, patients of different sex, subtype, and lesion size showed no significant differences.

Conclusions: Our studies demonstrated that HMME-PDT is effective in the treatment of PWS. The more prior PDL treatments, older age, lips involvement, PWS on limbs were adverse factors for Hemoporfin-PDT, while multiple HMME-PDT sessions can improve effective and response rate. Besides, ambient temperature and lesions temperature should be concerned, local cooling provides some relief from pain but may influence effect.