Loss of expression of TGF-βs and their receptors in chronic skin lesions induced by sulfur mustard as compared with chronic contact dermatitis patients

<p>Abstract</p> <p>Background</p> <p>Sulfur mustard (SM) is a blister-forming agent that has been used as a chemical weapon. Sulfur mustard can cause damage in various organs, especially the skin, respiratory system, and eyes. Generally, the multiple complications of mustard gas result from its alkalizing potency; it reacts with cellular components like DNA, RNA, proteins, and lipid membranes.</p> <p>TGF-β is a multi-functional cytokine with multiple biological effects ranging from cell differentiation and growth inhibition to extracellular matrix stimulation, immunosuppression, and immunomodulation. TGF-β has 3 isoforms (TGF-β 1, 2, 3) and its signaling is mediated by its receptors: R1, R2 and intracellular Smads molecules.</p> <p>TGF-β has been shown to have anti-inflammatory effects. TGF-βs and their receptors also have an important role in modulation of skin inflammation, proliferation of epidermal cells, and wound healing, and they have been implicated in different types of skin inflammatory disorders.</p> <p>Methods</p> <p>Seventeen exposed SM individuals (48.47 ± 9.3 years), 17 chronic dermatitis patients (46.52 ± 14.6 years), and 5 normal controls (44.00 ± 14.6 years) were enrolled in this study.</p> <p>Evaluation of TGF-βs and their receptors expressions was performed by semiquantitative RT-PCR. Only TGF1was analyzed immunohistochemically.</p> <p>Results</p> <p>Our results showed significant decreases in the expression percentages of TGF-β 1, 2 and R1, R2 in chemical victims in comparison with chronic dermatitis and normal subjects and significant decreases in the intensity of R1 and R2 expressions in chemical victims in comparison with chronic dermatitis and normal controls. (P value < 0.05)</p> <p>Conclusions</p> <p>TGF-βs and their receptors appear to have a noticeable role in chronic inflammatory skin lesions caused by sulfur mustard.</p

Prevalence of adult atopic dermatitis among nursing staff in a Taiwanese medical center: a pilot study on validation of diagnostic questionnaires

[[abstract]]Background: Atopic dermatitis (AD) is a chronic, relapsing dermatosis. Previous studies have focused mostly on pediatric patients, and investigations emphasizing adult AD have been limited. Objective: We set out to determine the 1-year prevalence and evaluate the validity of the International Study of Asthma and Allergies in Childhood (ISAAC) and United Kingdom Working Party (UKWP) AD questionnaires of adult AD in Taiwan. Methods: We conducted a cross-sectional study among nursing staff at a university hospital. The 1-year prevalence of AD was assessed by ISAAC and UKWP questionnaires. Subsequently, the dermatologists' diagnosis based on Hanifin and Rajka criteria was used as a reference for validation. Results: The overall response rate was 92.9%, equivalent to 1131 complete questionnaires. Ninety adult patients with AD (8%) were identified by dermatologists' diagnosis whereas ISAAC identified 107 (9.5%); sensitivity and specificity were 36.7% and 92.9%, respectively. UKWP identified 42 (3.7%) patients with AD; sensitivity and specificity were 42.2% and 99.6%, respectively. Using the receiver operating characteristic curve analysis, the UKWP criteria performed significantly better than its ISAAC counterpart. Further analysis indicated that modification of these criteria resulted in significant improvement in their diagnostic efficacy. More specifically, modified ISAAC showed 90.0% and 55.2% sensitivity and specificity, respectively, whereas modified UKWP demonstrated 82.2% and 94.2% sensitivity and specificity, respectively. Limitation: Most of the study subjects were female with a high educational background. Conclusion: Currently available questionnaire instruments do not perform well in the identification of adult patients with AD. Modification of the original questionnaires may allow for future large-scale epidemiologic studies

LED 590nm photomodulation reduces UVA-induced metalloproteinase-1 expression via upregulation of antioxidant enzyme catalase

[[abstract]]Background: Light at visible spectrum has been associated with anti-inflammatory and anti-aging effects. Ultraviolet A (UVA) radiation is the most important environmental factor associated with exogenous aging via induction of reactive oxygen species (ROS). Objective: In this study, we focused on elucidating the molecular mechanisms involved in biological effects associated with 590. nm light delivered from light emitting diode (LED). Methods: UVA-induced metalloproteinase-1 (MMP-1) expression in dermal fibroblast was used as a model system for investigation. Results: Pretreating cultured human fibroblasts with 590. nm light attenuated UVA-induced ROS, phosphorylated Jun N-terminal kinases, and MMP-1 expressions in a sequential manner. Pretreatment with potent antioxidant N-acetylcysteine produced similar effect, suggesting enhanced antioxidant capacity induced by 590. nm photomodulation. Further experiments demonstrated that 590. nm photomodulation attenuated UVA-induced ROS and MMP-1 expressions via mitochondrial retrograde signaling that augments the antioxidant enzyme expression in a peroxisome proliferators-activated receptor γ coactivator-1α-dependent manner. Conclusion: Our results provided possible mechanistic insights explaining the effect of visible light on treating clinical conditions associated with ROS-mediated dysfunctions

Topical tacrolimus has a limited direct effect on ultraviolet B-irradiated keratinocytes: Implications for its photocarcinogenic potential

[[abstract]]Background. Topical tacrolimus has shown remarkable clinical efficacy in treating many dermatoses. Combining ultraviolet (UV) B and tacrolimus is an intriguing therapeutic regimen, especially for treatment of vitiligo, for which combination therapy may show greater clinical efficacy than topical tacrolimus alone. The photocarcinogenic potential of such a regimen is unclear, and conflicting results have been reported by different investigators. Aim. To clarify this important clinical issue, we investigated the effects of tacrolimus on UVB-irradiated cultured keratinocytes in terms of apoptosis, differentiation, cell-cycle regulation and DNA damage. Methods. Cultured keratinocytes were treated with tacrolimus before and after UVB irradiation and the various cellular physiological changes were evaluated using trypan blue exclusion, terminal dUTP nick-end labelling, flow cytometry and Western blotting analyses. Results. Our results showed that treatment of tacrolimus before or after UVB irradiation had no significant effects on cultured keratinocytes in terms of cell apoptosis, transglutaminase-1, involucrin expression, cell-cycle progression and phospho-H2AX compared with UVB irradiation alone. Conclusion. The direct effect of tacrolimus on UVB-irradiated keratinocytes is small, suggesting that clinical regimens combining UVB and tacrolimus also have a limited direct effect on healthy skin compared with UVB irradiation alone