Effect of platelet-rich plasma combined with fractional CO2 laser treatment for acne scars

Abstract

Atrophic acne scars result from dermal inflammation caused by acne. Accordingly, destruction of dermal tissue followed by imperfect wound healing results in prolonged periods of time during which acne scars remain noticeable. Laser-mediated skin resurfacing induces regeneration and remodeling of dermal matrix, and thereby lessens the severity of acne scar. While fractional laser treatment reduces the chances of a patient experiencing adverse effects related to treatment, the resulting efficacy is also reduced compared to that obtained with classical laser therapy. Platelet-rich plasma (PRP) contains large amounts of growth factors which have the potential to enhance therapeutic efficacy of laser treatment. Furthermore, the rapid skin barrier recovery induced by PRP can reduce the chances of a patient experiencing certain adverse effects associated with laser treatment. The present study was conducted to evaluate the efficacy of PRP injections combined with fractional laser treatment for treating acne scars. Moreover, the underlying mechanism of this therapy was investigated using samples of human skin and an experimental cell model. Twenty-five subjects with mild to moderate acne scars were treated with two sessions of fractional CO2 laser therapy given with and without co-administration of PRP at a four-week interval in a split-face manner. Normal saline was injected intradermally on the control side of each patients face. Objective and subjective assessments of treatment results were conducted at baseline, 1, 3, 7 days after each treatment, and 4 weeks after the final treatment. Skin biopsy specimens were obtained at baseline, 1, 3, and 7 days after the first treatment session for investigation of molecular profiles associated with acute skin changes produced by laser plus PRP treatment. Additionally, the biological effects of combined fractional CO2 laser/PRP on fibroblast were explored in a fibroblast cell line model. The time-dependent expression of collagen and various growth factors was evaluated by western blot. Fractional CO2 laser treatment produced a significant improvement in acne scars

however, improvement on the PRP-treated side of the patients face was better than that on the control side. Evaluations based on the Investigators Global Assessment showed average improvements of 75% and 50% on the PRP-treated side and control side, respectively. Adverse effects such as erythema, swelling and oozing occurred with limited severity on the PRP-treated side. Scores on patient self-assessments of their satisfaction with treatment effectiveness were higher for the PRP plus laser treated side of their face. Patient skin biopsy specimens showed reactions to laser treatment. Compared with specimens of control skin, biopsy specimens of combined laser/PRP treated skin showed more compact and denser depositions of collagen in the papillary dermis. Expressions of TGFβ1 and TGFβ3 proteins as well as transcription of TGFβ 1, TGFβ 3 and collagen I mRNA were more highly elevated on the PRP-treated side of the face compared to the control side. Mediators such as β-catenin and αSMA, which are associated with the TGFβ fibrogenetic signaling pathway, showed greater upregulation on the PRP-treated side compared to the control side. In a cell model, PRP administration increased expressions of p-Akt, TGFβ1, TGFβ3, β-catenin, collagen I and collagen III in both dose-dependent and time dependent manners. Inhibition of p-Akt by pretreatment of the PI3K/Akt pathway did not limit expression of TGFβ1, but limited expression of β-catenin. Administration of PRP combination increased the efficacy of CO2 laser for treating acne scars and decreased the incidence of adverse effects. Elevated levels of TGFβ1 and TGFβ3 after combined fractional CO2 laser/PRP therapy may be a mechanism for the improvement in acne scars. Our clinical data combined with the data from cell experiments suggest that TGFβ induced by PRP treatment resulted in increased expression of αSMA in fibroblasts and collagen production via activating β-catenin through stimulation of p-Akt. This molecular signaling pathway is suggested as a mechanism for the clinical efficacy of combined fractional CO2 laser/PRP treatment.