Efficacy of radiofrequency combined with single-dot ultrasound efficacy for skin rejuvenation: A non-randomized split-face trial with blinded response evaluation.

BACKGROUND: High-intensity focused ultrasound (HIFU) and radiofrequency (RF) are non-invasive modalities for skin rejuvenation, but their combined effects have not been evaluated. OBJECTIVE: We evaluated and compared the efficacy of HIFU alone and combined HIFU and bipolar RF using a newly designed probe. METHODS: Twenty-two Korean adults with facial wrinkles and aging underwent treatment on both sides of their face: HIFU-only on the left and HIFU combined with RF on the right. Skin parameters were measured at different time points to evaluate the improvement in skin rejuvenation. RESULTS: HIFU treatment significantly improved skin parameters, including pore volume and number, skin elasticity, depth of eye wrinkles, degree of sagging in the eye area, nasolabial folds and cheeks, volume of the jawline, skin density, and permittivity. Furthermore, combining bipolar RF with HIFU treatment enhanced efficacy in reducing pore number, improving skin elasticity, diminishing eye wrinkle depth, and increasing skin moisturization. These findings indicate that bipolar RF can synergically improve skin rejuvenation by providing a thermal effect to the upper papillary dermis, which is more superficial than the target area of HIFU. CONCLUSION: Combining HIFU with bipolar RF synergistically improves skin rejuvenation, including pore reduction, periorbital wrinkle improvement, skin elasticity, and skin moisturization.

15-deoxy prostaglandin J2, the nonenzymatic metabolite of prostaglandin D2, induces apoptosis in keratinocytes of human hair follicles: a possible explanation for prostaglandin D2-mediated inhibition of hair growth.

Recent studies have shown that prostaglandin D2 (PGD2) and its nonenzymatic metabolite, 15-deoxy-Δ(12,14)-prostaglandin J2 (15-dPGJ2), inhibit in vitro growth of explanted human hair follicles and inhibit hair growth in mice through the GPR44 (DP2). However, the underlying mechanism is still unclear. In this study, we first investigated the expression of DP2 in human hair follicles and in cultured follicular cells. We found that DP2 is strongly expressed in the outer root sheath (ORS) cells and weakly expressed in the dermal papilla (DP) cells. We observed slight growth stimulation when ORS and DP cells were treated with PGD2. We also observed slight growth stimulation when DP and ORS cells were treated with low concentrations (0.5 and 1 µM) of 15-dPGJ2. However, 5 µM 15-dPGJ2 inhibited the viability and caused apoptosis of both cell types. Exposure of cultured human hair follicles to 15-dPGJ2 resulted in significant apoptosis in follicular keratinocytes. Altogether, our data provide an evidence that 15-dPGJ2 promotes apoptosis in follicular keratinocytes and provide rationale for developing remedies for the prevention and treatment of hair loss based on DP2 antagonism.