Fractional Radiofrequency Microneedling Combined With Fractional Carbon Dioxide Laser Treatment for Striae Distensae.

BACKGROUND AND OBJECTIVES: To evaluate the safety and effectiveness of combined fractional radiofrequency microneedling (FRM) and fractional carbon dioxide (FCO2 ) laser treatment for striae distensae and to compare the results to those of FRM alone and those of FCO2 alone. STUDY DESIGN/MATERIALS AND METHODS: Adult women (Fitzpatrick skin types III-IV) with striae distensae on the abdomen or calf were enrolled in this study. Each lesion was divided into three regions, with each region assigned to one of the three treatments (FCO2 , FRM, or combined FCO2 and FRM). Global photographic assessments were performed by three dermatologists and by patients using a scored visual analog scale (VAS). Additionally, each lesion was evaluated using a skin imaging analyzer and a diagnostic ultrasound system. RESULTS: All 19 female subjects had an average body mass index of 23.85 kg/m2 . The global assessment by dermatologists indicated a significant improvement in the combined treatment group (6.1) compared with the other groups (4.3 and 5.1 in the FRM and FCO2 groups, respectively; P < 0.05), and that by the patients indicated a significant improvement in the combined treatment group (6.3) compared with the FRM group (5.1; P = 0.02). Ultrasound results showed significantly increased skin thickness and dermal density (204.9 µm and 8.8%; both P < 0.05) in the combined treatment group. However, results of the skin imaging analysis showed a higher average level of melanin and redness indices in the combined treatment group than in the FRM group (P < 0.001, P < 0.01, respectively), but not in the FCO2 group (P = 0.15, P = 0.11, respectively). CONCLUSION: Combined FRM and FCO2 treatments resulted in slightly better clinical outcomes than single treatments, and the side effects of the treatment, such as pigmentation and persistent erythema, did not result in more serious events to a level similar to that of FCO2 alone. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Biopositive effects of low-dose UVB on epidermis: coordinate upregulation of antimicrobial peptides and permeability barrier reinforcement.

Whereas high-dose ultraviolet B (UVB) is detrimental to the epidermal permeability barrier, suberythemal doses of UVB are used to treat atopic dermatitis (AD), which is characterized by defective permeability barrier and antimicrobial function. As epidermal permeability barrier and antimicrobial peptide (AMP) expression are coregulated and interdependent functions, we hypothesized that suberythemal doses of UVB exposure could regulate AMP expression in parallel with permeability barrier function. Hairless mice were exposed to 40 mJ cm(-2) UVB (about 1/2 minimal erythema dose) daily for 1 or 3 days. Twenty-four hours after the last exposure, epidermal barrier function was assessed and skin specimens were taken for western blotting, immunohistochemistry, and quantitative reverse transcription-PCR for mouse beta-defensin (mBD)-2, mBD3 and cathelin-related antimicrobial peptide (CRAMP). mRNA levels of the vitamin D receptor (VDR), 1alpha-hydroxylase and key epidermal lipid synthetic enzymes were also quantified. After 3 days of UVB exposure, acceleration of barrier recovery and augmentation in expression of epidermal differentiation markers (for example, involucrin and filaggrin) occurred in parallel with increased mBD2, mBD3, and CRAMP expression at both the mRNA and protein level. VDR, 1alpha-hydroxylase, and the major epidermal lipid synthetic enzymes were also upregulated. When an inhibitor of 1alpha, 25 dihydroxyvitamin D(3) formation, ketoconazole, was applied immediately after UVB exposure, the cutaneous vitamin D system was inhibited, which in turn blocked epidermal lipid synthesis, AMP expression, and permeability barrier homeostasis, suggesting that the beneficial effect of low-dose UVB depends, at least in part, on activation of the cutaneous vitamin D system. Our results provide new insights into the mechanisms whereby low-dose UVB comprises effective therapy for AD.

Effects of a multilamellar emulsion on glucocorticoid-induced epidermal atrophy and barrier impairment.

Skin atrophy is one of the most frequent side-effects of the topical glucocorticoid. Skin barrier impairment has also been reported as a steroid-induced side effect. Although there have been various studies on preventing or minimizing this atrophogenic effect, little has been reported about preventing barrier impairment. This study was performed to determine the effects of a multilamellar emulsion (MLE) that had a well-ordered lamellar structure on the steroid-induced barrier impairment and epidermal atrophy. To confirm these effects of MLE, 0.05% clobetasol-17-propionate (CP) and 0.05% clobetasol-17-propionate in MLE (MLE/CP) were topically applied to both flanks of hairless mice for 9 days. The topically applied CP induced a significant impairment of the epidermal permeability barrier, and MLE/CP also did not have a preventive effect on this change. However, skinfold thickness studies and histological studies showed that MLE/CP significantly reduced the steroid-induced atrophy. The topical application of MLE/CP was also shown to have a preventive effect on the steroid-induced increase of the stratum corneum (SC) surface pH. In addition, the electron microscopic findings showed relatively well-conserved lamellar bilayers in the skin treated with MLE, as compared to CP only. The results showed that the topical application of MLE immediately after CP treatment prevented the glucocorticoid-induced transepidermal water loss values increase. Light microscopy measurements showed that the skin treated with MLE immediately after CP treatment for 1 week had a slightly lower decline of skin thickness than did the CP-treated skin. These results suggest that MLE should be effective for preventing glucocorticoid-induced epidermal atrophy and for repairing the barrier impairment.