The use of lasers and light sources in skin rejuvenation

Combined multilevel anti-aging strategies and practical applications of dermocosmetics in aesthetic procedures

Management of the signs of facial aging and other cosmetic skin problems have greatly evolved in the past years. People are also seeking to improve their well-being and global skin appearance, and when they consider using cosmetic procedures, they expect natural and long-lasting aesthetic results. Combined dermocosmetic approaches that address the signs of facial aging at all levels are increasingly being used by dermatologists to meet patient expectations while ensuring their safety. Minimally invasive and reversible procedures that can be performed in only one session are popular approaches for skin restructuring and volumizing as they are flexible, rapid and less burdensome for patients. These interventions can achieve even better outcomes when they are combined with cosmeceuticals as pre- or post-procedural adjuvants to prepare the skin, accelerate recovery and sustain results. The use of topical dermocosmetics is also recommended as part of the daily skin care routine to improve skin quality and help maintain skin barrier function. This review thus outlines the most commonly used combined multilevel anti-aging strategies, which start by addressing the deepest skin layers and then the more superficial signs of skin aging. Examples of multi-active cosmeceuticals and skin delivery enhancing systems are also presented, together with examples of the use of dermocosmetics as supportive care for aesthetic procedures, to provide insights into current applications of dermocosmetic products.

Exploring the Safety and Efficacy of Organic Light-Emitting Diode in Skin Rejuvenation and Wound Healing

PURPOSE

Photobiomodulation (PBM), encompassing low-energy laser treatment and light-emitting diode (LED) phototherapy, has demonstrated positive impacts on skin rejuvenation and wound healing. Organic light-emitting diodes (OLEDs) present a promising advancement as wearable light sources for PBM. However, the biological and biochemical substantiation of their skin rejuvenation and wound healing effects remains limited. This study aimed to ascertain the safety and efficacy of OLEDs as a next-generation PBM modality through comprehensive in vitro and in vivo investigations.

MATERIALS AND METHODS

Cell viability assays and human ex vivo skin analyses were performed after exposure to OLED and LED irradiation to examine their safety. Subsequent evaluations examined expression levels and wound healing effects in human dermal fibroblasts (HDFs) using quantitative reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, and wound healing assays post-irradiation. Additionally, an in vivo study was conducted using a ultra violet (UV)-irradiated animal skin model to explore the impact of OLED exposure on dermal collagen density and wrinkles, employing skin replica and tissue staining techniques.

RESULTS

OLED irradiation had no significant morphological effects on human skin tissue, but caused a considerably higher expression of collagen than the control and LED-treated groups. Moreover, OLED irradiation reduced the expression levels of matrix metalloproteinases (MMPs) more effectively than did LED on HDFs. OLED irradiation group in HDFs had significantly higher expression levels of growth factors compared to the control group, but similar to those in the LED irradiation group. In addition, OLED irradiation on photo-aged animal skin model resulted in increased collagen fiber density in the dermis while reducing ultra violet radiation-mediated skin wrinkles and roughness, as shown in the skin replica.

CONCLUSION

This study established comparable effectiveness between OLED and LED irradiation in upregulating collagen and growth factor expression levels while downregulating MMP levels in vitro. In the UV-irradiated animal skin model, OLED exposure post UV radiation correlated with reduced skin wrinkles and augmented dermal collagen density. Accelerated wound recovery and demonstrated safety further underscore OLEDs' potential as a future PBM modality alongside LEDs, offering promise in the realms of skin rejuvenation and wound healing.

Male facial rejuvenation using a combination 633, 830, and 1072 nm LED face mask

Home-based photobiomodulation is a popular treatment modality for patients seeking non-invasive aesthetic treatment. Studies demonstrate that photobiomodulation is effective for skin rejuvenation, which is aimed at improving the overall appearance of the skin by reducing fine lines and wrinkles and improving skin texture, skin tone, and dyspigmentation. Most current skin rejuvenation research focuses on treatments in women. However, men's aesthetics remains an underserved market. A combined red light (RL) and near-infrared (NIR) light-emitting diode (LED) has been designed specifically to target male skin, which may have different physiological and biophysical properties compared to female skin. Herein, the safety and efficacy of a commercially available RL and NIR (633, 830, and 1072 nm) LED array designed to be worn as a face mask was assessed. Primary outcomes included adverse events and facial rejuvenation as determined by participant-reported satisfaction scales and quantitative digital skin photography and computer analysis after 6 weeks of treatment. The participants reported overall favorable results and improvements in all individual categories, were satisfied with the treatment, and would recommend the product to others. The participants perceived the greatest improvement in fine lines and wrinkles, skin texture, and youthful appearance. Photographic digital analysis demonstrated favorable improvements in wrinkles, UV spots, brown spots, pores, and porphyrins. These results support the use of RL and NIR to treat male skin. Advantages of the LED facemask include its safety, efficacy, convenient home-based use, minimal associated downtime, simple operation, non-invasiveness, and appreciable results in as few as 6 weeks.

Biocompatible Triple-Helical Recombinant Collagen Dressings for Accelerated Wound Healing in Microneedle-Injured and Photodamaged Skin

Skin rejuvenation procedures such as microneedling and laser resurfacing have gained global popularity in medical cosmetology, leading to acute skin wounds with persistent pain, erythema, and edema. A variety of dressings have been explored to repair these postoperative skin injuries; however, their inadequate biocompatibility and bioactivity may raise concerns about undesirable efficacy and complications. Herein, we developed biocompatible and nonirritating triple-helical recombinant collagen (THRC) dressings for accelerated healing of microneedle-injured and photodamaged acute skin wounds. Circular dichroism (CD) measurements of THRC from various batches exhibited triple-helical structure characteristics of collagen. Cell experiments using L929 fibroblasts revealed that THRC dressings possess superior biocompatibility and bioactivity, significantly elevating the proliferation and adhesion of fibroblasts. In vivo, skin irritation tests of New Zealand rabbits demonstrated that the THRC dressings are gentle, safe, and non-irritating. Histological analysis of the animal model studies in photodamaged skin wounds using H&E and Masson’s trichrome staining revealed that 4 days of treatment with the THRC dressings effectively healed the damaged dermis by accelerating re-epithelialization and enhancing collagen deposition. In vivo studies of microneedle-injured rat defects showed that THRC dressings of varying concentrations exhibit the same rapid epithelialization rates at 48 h as commercial bovine collagen dressings. The highly biocompatible and bioactive recombinant collagen dressings may provide an advanced treatment of acute skin wounds, indicating attractive applications in postoperative care of facial rejuvenation.

Red Light Mitigates the Deteriorating Placental Extracellular Matrix in Late Onset of Preeclampsia and Improves the Trophoblast Behavior

Preeclampsia is a serious pregnancy disorder which in extreme cases may lead to maternal and fetal injury or death. Preexisting conditions which increase oxidative stress, e.g., hypertension and diabetes, increase the mother's risk to develop preeclampsia. Previously, we established that when the extracellular matrix is exposed to oxidative stress, trophoblast function is impaired, and this may lead to improper placentation. We investigated how the oxidative ECM present in preeclampsia alters the behavior of first trimester extravillous trophoblasts. We demonstrate elevated levels of advanced glycation end products (AGE) and lipid oxidation end product 4-hydroxynonenal in preeclamptic ECM (28%, and 32% increase vs control, respectively) accompanied with 35% and 82% more 3-chlorotyrosine and 3-nitrotyrosine vs control, respectively. Furthermore, we hypothesized that 670 nm phototherapy, which has antioxidant properties, reverses the observed trophoblast dysfunction as depicted in the improved migration and reduction in apoptosis. Since NO is critical for placentation, we examined eNOS activity in preeclamptic placentas compared to healthy ones and found no differences; however, 670 nm light treatment triggered enhanced NO availability presumably by using alternative NO sources. Light exposure decreased apoptosis and restored trophoblast migration to levels in trophoblasts cultured on preeclamptic ECM. Moreover, 670 nm irradiation restored expression of Transforming Growth Factor (TGFβ) and Placental Growth Factor (PLGF) to levels observed in trophoblasts cultured on healthy placental ECM. We conclude the application of 670 nm light can successfully mitigate the damaged placental microenvironment of late onset preeclampsia as depicted by the restored trophoblast behavior.

Clinical Effect of Photobiomodulation on Wound Healing of Diabetic Foot Ulcers: Does Skin Color Needs to Be Considered?

Diabetic foot ulcers (DFUs) are one of the most common complications of diabetes. DFUs impede patients' quality of life and are known to be unresponsive to conventional therapy. Photobiomodulation (PBM) is a pain-free, noninvasive treatment method that has been shown to promote chronic wound healing and has been successfully used for the treatment of DFUs. Since skin tone and color can affect the way light interacts with tissue, studies should take this into consideration when determining protocols for the use of PBM. This review is aimed at critically evaluating data of existing studies conducted to evaluate the clinical effect of PBM on DFUs, taking skin color into consideration. A literature search was conducted and resulted in articles on cell studies, animal studies, and clinical trials. Only 13 clinical trials and 2 clinical case studies were adopted and used in this review. All the clinical trials adopted for this review show evidence that PBM together with conventional treatment results in an increased healing rate of DFUs; however, only one study adjusted their protocol according to skin color. There are not enough studies conducted on people of color to determine the safety and efficacy of PBM therapy in such ethnic groups. Future randomized, placebo-controlled clinical trials are necessary on PBM and DFUs and should take skin color into consideration.

Phonosurgery: A review of current methodologies

Cold-steel has served as the gold standard modality of phonosurgery for most of its history. Surgical laser technology has revolutionized this field with its wide use of applications. Additional modalities have also been introduced such as coagulative lasers, photodynamic therapy, and cryotherapy. This review will compare the surgical modalities of cold steel, surgical lasers, phototherapy and cryotherapy. The mechanism of action, tissue effects and typical uses will be addressed for each modality.

The Use of a Light-Emitting Diode Device for Neck Rejuvenation and Its Safety on Thyroid Glands

Home-use light-emitting diodes (LEDs) are attracting growing attention regarding their anti-aging effects. Although most previous studies on the use of LED devices as a form of low-level laser therapy reported no significant adverse events, questions regarding the safety of using a light source on secretory tissues have been raised. This study aimed to assess the safety and efficacy of a home-use LED device for neck skin rejuvenation, particularly regarding its effect on thyroid gland morphology and function. Thyroid function tests and ultrasonographic analyses showed no significant changes after 16 weeks of LED use. Evaluation using the Lemperle wrinkle scale and global improvement scales by both investigators and subjects showed significant improvement after 16 weeks of daily application, as well as 8 weeks after discontinuation. Biophysical parameters, such as hydration, elasticity, and density, also showed significant improvements. Hence, the long-term use of the LED device was safe and effective for neck rejuvenation, and showed no significant side effects on the adjacent thyroid and parathyroid glands.

Textile-integrated polymer optical fibers for healthcare and medical applications

With ever growing interest in far-reaching solutions for pervasive healthcare and medicine, polymer optical fibers have been rendered into textile forms. Having both fiber-optic functionalities and traditional fabric-like comfort, textile-integrated polymer optical fibers have been advocated to remove the technical barriers for long-term uninterrupted health monitoring and treatment. In this context, this paper spotlights and reviews the recently developed textile-integrated polymer optical fibers in conjunction with fabrication techniques, applications in long-term continuous health monitoring and treatment, and future perspectives in the vision of mobile health (mHealth), as well as the introductory basics of polymer optical fibers. It is designed to serve as a topical guidepost for scientists and engineers on this highly interdisciplinary and rapidly growing topic.

Assessment of Laser Effects on Skin Rejuvenation

Laser skin resurfacing has changed the approach of facial skin rejuvenation over the past decade. This article evaluates the laser effects on skin rejuvenation by the assessment of laser characteristics and histological and molecular changes, accompanied by the expression of proteins during and after laser-assisted rejuvenation of skin. It is important to note that different layers of skin with different cells are normally exposed to the sun's UV radiation which is the most likely factor in aging and damaging healthy skin. To identify the expression of proteins, using validated databases and reviewing existing data could reveal altered proteins which could be analyzed and mapped to investigate their expression and their different effects on cell biological responses. In this regard, proteomics data can be used for better investigation of the changes in the proteomic profile of the treated skin. Different assessments have revealed the survival and activation of fibroblasts and new keratinocytes with an increase of collagen and elastin fibers in the dermis and the reduction of matrix metalloproteinases (MMPs) and heat shock proteins (HSPs) as a result of different low-power laser therapies of skin. There are a wide range of biological effects associated with laser application in skin rejuvenation; therefore, more safety considerations should be regarded in the application of lasers in skin rejuvenation.