Q-switched 1064 nm Nd-Yag nanosecond laser effects on skin barrier function and on molecular rejuvenation markers in keratinocyte-fibroblasts interaction

Platelet-Rich Plasma Injection Combined With Q-Switched Ruby Laser in the Treatment of Periorbital Hyperpigmentation

BACKGROUND

Periorbital hyperpigmentation is a prevalent skin condition that represents a large quantity of cases seen in cosmetic dermatology. Patients tend to be left with pigmentation after Q-switched ruby laser treatment, especially the perioribital area.

AIMS

The study is conducted to compare the effect of PRP injection combined with laser therapy versus laser alone for periorbital hyperpigmentation treatment.

PATIENTS/METHODS

In this single-center, case-control study, 30 patients with periorbital hyperpigmentation were allocated to receive PRP injection injection after Q-switched ruby laser or Q-switched ruby laser only, followed by a 12-week and 24-week follow-up visit. Visual analogue scale, Sadick tear trough rating scale, and patients' self-evaluation were used to evaluate the therapeutic effect.

RESULTS

The combined group achieved a better improvement in long-term effect and had effect on facial rejuvenation. Patient satisfaction was higher in the combined group. Erythema and mild pain were the most common adverse reactions of both groups.

CONCLUSIONS

Combining with PRP injection can improve the therapeutic effect of Q-switched ruby laser in treating periorbital hyperpigmentation and lessen the risk of post-inflammatory hyperpigmentation, indicating a new option for POH treatment.

Prospective study of using 1064-nm Q-switched Nd: YAG combined with radiofrequency-imported vitamin C on pigmented infraorbital dark circles

Infraorbital dark circles are a common manifestation of periorbital melanosis, which is aesthetically defective and bring a negative impact on life quality. However, there is no acknowledged treatment for infraorbital dark circles. The 1064-nm Q-switched Nd: YAG laser (QSNYL) is commonly utilized to treat hyperpigmentation disorders. Radiofrequency (RF) therapy can improve the transdermal absorption rate of drugs. A prospective clinical trial was conducted to investigate the clinical efficacy and safety of 1064-nm QSNYL combined with RF-imported vitamin C for the treatment of infraorbital dark circles. A questionnaire was used to explore the relevant factors affecting the severity of infraorbital dark circles. A total of 30 patients with pigmented infraorbital dark circles were enrolled in this clinical trial. Each participant received 4 treatments and was followed up for at least 12 months after the last treatment.We focused on the overall change in the appearance of the included participants before and after treatment, by using satisfaction evaluation.In order to reduce evaluation bias, the vivo reflectance confocal microscopy images were taken on days 1 and 120 to detect pigmentation. The questionnaire survey before treatment showed that high-frequency makeup was positively and statistically significant with the severity of infraorbital dark circles (p < 0.01). Both participants and independent evaluators found that the hyperpigmentation in the infraorbital region was significantly reduced after combined treatment with high treatment satisfaction. The density of melanin particles in the infraorbital dark circles region showed a decreased trend. No significant side effects were observed. The 1064-nm QSNYL combined with RF-imported vitamin C is a safe and effective treatment for pigmented infraorbital dark circles by reducing melanin particles.

Efficacy of Picosecond Laser in Clinical, Histopathology, and Immunohistochemistry Examination in Indonesian Wrinkled Skin

Introduction: The elderly population wants to improve skin function and maintain a youthful appearance without wrinkles. Laser is one of the highly developed and widely used therapeutic modalities of skin aging by stimulating dermal collagen formation. Picosecond laser therapy is performed on skin with wrinkles to determine the mechanism of wrinkle improvement with a picosecond laser through an increasing in tissue inhibitor of metalloproteinases 1 (TIMP-1), and a decrease in matrix metalloproteinase-1 (MMP-1), which was confirmed by collagen density. Methods: The study was started from March 2021 to July 2021 at URJ Dr. Soetomo Hospital Surabaya and Surabaya Skin Centre. Twenty patients meeting the inclusion criteria of being 36-55 years of age and having a wrinkle in the forearm were enrolled by random sampling. Each sample data was recorded, the average TIMP-1, MMP-1, collagen density, and clinical wrinkles were calculated, and the laser was performed by using a picosecond 755 nm laser. Results: All patients showed a moderate pre-test wrinkle scale. The figure for TIMP-1 and MMP-1 after therapy was higher. The MMP-1/TIMP-1 ratio in wrinkles treated by using a picosecond laser was lower but insignificant than before. The picture of collagen density indicates that collagen density after laser therapy was higher than before. Conclusion: The result of clinical examination, histopathology, and immunohistochemistry in this research explained that a picosecond 755 nm laser with DLA is an effective therapy for wrinkles in Indonesian patients without any adverse effects.

Expert consensus on perioperative integrated skincare for noninvasive energy-based device aesthetic procedures in clinical practice in China

BACKGROUND

Noninvasive energy-based device (NI-EBD) aesthetic procedures has recently gained widespread usage for treating various skin conditions, enhancing skin texture and performing rejuvenation-related procedures. However, practically all NI-EBD procedures result in variable degrees of damage to the skin barrier, inducing pathological and physiological processes such as oxidative stress and inflammation, and only a small percentage of individuals possess the innate ability to restore it.

OBJECTIVE

To introduce the concept of integrated skincare and establish standardized operational procedures for perioperative integrated skincare, and furnish a theoretical basis for clinical diagnosis and treatment performed by professional medical aestheticians.

METHODS

The author leveraged domestic and international guidelines, clinical practice expertise and evidence-based research, adapting them to suit the specific circumstances in China.

RESULTS

The consensus were provided four parts, including concept and essence of integrated skincare, integrated skincare significance during the perioperative phase of NI-EBD procedures, active ingredients and functions of effective skincare products, standardized perioperative skincare procedure for NI-EBD procedures and precautions. For the standardized perioperative skincare procedure, four recommendations were listed according to different stages during NI-EBD procedures.

CONCLUSION

These recommendations create the 'Expert Consensus on Perioperative Integrated Skincare for Noninvasive Energy-Based Device Aesthetic Procedures in Clinical Practice in China'.

Comparison of 755-nm picosecond alexandrite laser versus 1064-nm Q-switched Nd:YAG laser for melasma: A randomized, split-face controlled, 2-year follow-up study

OBJECTIVES

Pulsed laser treatment of melasma has shown some promising results. To compare the effectiveness and safety of 755-nm picosecond alexandrite laser (PSAL) fitted with diffractive lens array (DLA) versus 1064-nm Q-switched neodynimum:yttrium aluminum garnet laser (QSNYL) for the treatment of melasma.

METHODS

We conducted a randomized, split face controlled, 2-year follow-up study. Each face was divided into two parts, each side receiving three treatments with either PSAL or QSNYL at 1 month intervals. Modified Melasma Area Severity Index scores (mMASI), pain scores, patient satisfaction and adverse events were recorded. In vivo reflectance confocal microscopy (RCM) images were acquired.

RESULTS

Twenty subjects were enrolled and three dropped out. At 6 months, mMASI scores were significantly lower than baseline for QSNYL sides (p = 0.022), with no statistically significant difference between PSAL sides before and after treatment, PSAL sides versus QSNYL sides, or patient satisfaction scores. QSNYL treatment was associated with less pain (p = 0.014). No serious adverse events were reported. In the PSAL sides RCM showed a large number of dendritic melanocytes infiltrated in the dermis at 2 weeks and 4 weeks after treatment. Ten patients (58.82%) reported recurrence or exacerbation at 2-year follow-up with no statistically significant difference between the two lasers.

CONCLUSIONS

QSNYL demonstrated short term clinical efficacy for melasma, but did not provide any additional benefit compared to PSAL with DLA. QSNYL was associated with less pain. There was a high recurrence rate at 2-year follow-up. RCM allowed the detection of cellular changes in melasma lesions.

Pilot Study to Demonstrate Improvement in Skin Tone and Texture by Treatment with a 1064 nm Q-Switched Neodymium-Doped Yttrium Aluminum Garnet Laser

BACKGROUND

The 1064 nm Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG) laser was developed to treat unwanted pigmentation in the skin such as lentigines caused by photoaging, and tattoos from dye/ink insertion. This laser has also been used for non-ablative epidermal rejuvenation (skin toning).

OBJECTIVE

To evaluate changes in skin tone, skin texture and overall improvement after a series of treatments with the QS Nd:YAG laser.

METHODS

Participants received seven full-face treatments with M22 or Stellar M22, a 1064 nm QS Nd:YAG laser, at 2-week intervals. The investigators and participants evaluated the improvement in skin tone and texture at 1, 3 and 6 months after the last treatment. Patient satisfaction, patient discomfort, downtime and adverse events were recorded. Histological changes in the treated area were also evaluated.

RESULTS

Thirteen women with a median age of 45 years (range, 34-61 years) were included in the study. The majority of the participants (53.9%) had skin type VI. One month after the last treatment session, 38% of participants reported good to very good improvement. This value increased to 100% participant improvement at both the 3-month and 6-month follow-up visits. The reduction in melanin index and the histological analysis demonstrated that the laser procedure contributed to a reduction in epidermal melanin content. Treatments were not associated with high levels of pain or discomfort. The most common immediate post-treatment response was erythema and edema. Most participants were satisfied with the resulting treatment outcome.

CONCLUSION

Skin treatment with the 1064 nm QS Nd:YAG laser module on the M22 and Stellar M22 devices, using a large spot size, low fluence, moderately high repetition rate, improves skin tone and texture in patients with skin types II-VI.

Effect of photobiomodulation on inflammatory cytokines produced by HaCaT keratinocytes

Objective

to evaluate the effects of the red and near-infrared wavelength lasers in isolated and simultaneous way on the modulation of inflammatory cytokines produced by human keratinocytes (HaCaT) challenged by cytokines of human monocytes stimulated by lipopolysaccharide from Escherichia coli.

Design

HaCaT cells was previously exposed to the laser with wavelengths red (660 nm), near-infrared (808 nm). Then, HaCat cells were stimulated with the supernatant of lipopolysaccharide-challenged peripheral blood cells. The cytokines expressed by HaCat cells were measured using multiplex CBA assay.

Results

HaCaT cells increased the production of inflammatory cytokines when stimulated with infrared laser compared to the control group (IFN-α2, IFN-γ, TNF-α, MCP-1, IL-6, IL-8, IL-10, IL -12p70, IL -17A, IL-23, IL-33), the red laser group (IFN-γ and IL-23) and the group of two lasers used simultaneously (IFN-α2, IFN-γ, IL-6 and IL-8, IL-17A, IL-18 and IL-23) (p < 0.05). The red laser also stimulated an increase in the expression of IFN-α2 by HaCaT cells in relation to the control group (p < 0.05).

Conclusion

Infrared laser, with an energy density of 5 J/cm2, appear to be able to modulate inflammatory cytokines produced by HaCaT cells challenged by human monocyte cytokines.

Q-switched Nd:YAG laser protects human keratinocytes from oxidative stress and inflammation via AhR-Nrf2 pathway

In recent years, some treatments for esthetic and pathologic skin conditions have increasingly been based on the use of non-ablative neodymium-doped yttrium aluminum garnet (Nd:YAG) laser due to its greater penetration ability than other types of lasers, few contraindications, minimal side effects, no damage for epidermidis and the rapid recovery of the treated patients. The skin is frequently exposed to many stressors such as radiation, toxic substances, metabolites, foods, mechanical insults, and allergen exposition that cause oxidative damage and have a decisive influence on the aging process. The imbalance between reactive oxygen species, reactive nitrogen species, and the malfunctioning of the antioxidant defense system promotes the establishment of an excessive inflammatory process, which can induce various diseases including cancer and neurodegenerative disorders. The present study investigated the cytoprotective function of Q-switched Nd:YAG laser against stress aging and cell injury in HaCaT cells. We evaluated the effect of the laser on antioxidant defenses, inflammation, metalloproteinases' expression, and the AhR-Nrf2 pathway. Q-switched Nd:YAG is able to upregulate the AhR pathway and the expression of IL-6 and TGF-β, which are involved in wound repair process, and to downregulate the expression of MMP-2 and 9, so preventing the collagen degradation. Q-switched Nd:YAG can stimulate the cellular antioxidant defenses by activating the AhR-Nrf2 system.

The quantitative analysis of low-concentration (2%) ALA-PDT assisted with Q-switch 1064-nm Nd:YAG laser for acne vulgaris treatment

Conventional 5-aminolevulinic acid-photodynamic (ALA-PDT) therapy (10-20%) has been widely applied for moderate-to-severe acne. The aim of this study is to investigate the effects of non-ablative Q-switched 1064-nm Nd:YAG laser-assisted ALA-PDT with low concentration (2%) on the treatment of acne vulgaris. Enrolled patients were randomly assigned to 2 groups. One group received combined therapy of 2% ALA-PDT and non-ablative Q-switched 1064-nm Nd:YAG laser, and the other received only 2% ALA-PDT. Patients in each group had received 3-session treatments with 4-week intervals (week 0, 4, and 8). Sebum secretion, melanin index, erythema index, and transepidermal water loss (TEWL) were assessed at week 2, 8, 12, and 24. VISIA® skin image system score and global esthetic improvement scale (GAIS) were also evaluated. Twenty-four participants were enrolled and evenly randomized to two groups. Significant improvement in sebum secretion was noted in combined therapy group compared to the monotherapy group at week 12 (37.5% versus 16.3%), and the improvement would still be noted until week 24 (18.3% versus 17.4%). Combined group also showed more severe melanin index and erythema index after treatment. For VISIA® skin analysis, patients in combined group had better percentile ranking in porphyrins and red-light images. There were no significant differences in GAIS at the end of the follow-up between each group, whereas higher proportion of satisfaction was noted in combined group at week 2. With the assistance of laser, low concentrations (2%) of 5-ALA can provide effective phototoxic reactions in treating acne vulgaris. The satisfaction of patients is high with acceptable adverse effects.

Photobiomodulation Reduces the Cytokine Storm Syndrome Associated with COVID-19 in the Zebrafish Model

Although the exact mechanism of the pathogenesis of coronavirus SARS-CoV-2 (COVID-19) is not fully understood, oxidative stress and the release of pro-inflammatory cytokines have been highlighted as playing a vital role in the pathogenesis of the disease. In this sense, alternative treatments are needed to reduce the level of inflammation caused by COVID-19. Therefore, this study aimed to investigate the potential effect of red photobiomodulation (PBM) as an attractive therapy to downregulate the cytokine storm caused by COVID-19 in a zebrafish model. RT-qPCR analyses and protein-protein interaction prediction among SARS-CoV-2 and Danio rerio proteins showed that recombinant Spike protein (rSpike) was responsible for generating systemic inflammatory processes with significantly increased levels of pro-inflammatory (il1b, il6, tnfa, and nfkbiab), oxidative stress (romo1) and energy metabolism (slc2a1a and coa1) mRNA markers, with a pattern similar to those observed in COVID-19 cases in humans. On the other hand, PBM treatment was able to decrease the mRNA levels of these pro-inflammatory and oxidative stress markers compared with rSpike in various tissues, promoting an anti-inflammatory response. Conversely, PBM promotes cellular and tissue repair of injured tissues and significantly increases the survival rate of rSpike-inoculated individuals. Additionally, metabolomics analysis showed that the most-impacted metabolic pathways between PBM and the rSpike treated groups were related to steroid metabolism, immune system, and lipid metabolism. Together, our findings suggest that the inflammatory process is an incisive feature of COVID-19 and red PBM can be used as a novel therapeutic agent for COVID-19 by regulating the inflammatory response. Nevertheless, the need for more clinical trials remains, and there is a significant gap to overcome before clinical trials can commence.

Morphologic and molecular biologic analyses of the skin rejuvenation effect of the fractional 1064-nm picosecond laser: An animal study

OBJECTIVES

Application of the picosecond laser in the field of dermatology has expanded from tattoo removal to skin rejuvenation on a clinical basis. Although various mechanisms of pigment removal have been elucidated, the molecular changes associated with skin rejuvenation have yet to be identified. The aim of this study was to explore the theoretical basis and to evaluate the efficacy of skin rejuvenation using a 1064-nm fractional picosecond laser in a mouse model.

METHODS

We conducted an in vivo study using a fractional picosecond laser on the skin of old and young female hairless mice and performed topographical, histological, micro-, and electron microscopic assessments.

RESULTS

The topography of the skin surface was enhanced and showed increased dermal thickness on histological examination. Electron microscopy revealed disarranged collagen bundles with microspaces and vascular leakage in the upper dermis. Levels of collagen synthesis markers and various inflammatory cytokines, such as procollagens, interleukin-1β, tumor necrosis factor-α, and heat shock proteins, were elevated in the laser-treated skin.

CONCLUSIONS

This study provides a possible mechanism for the skin rejuvenation effect of fractional picosecond laser that has been reported previously in clinical observations. Based on our findings, the fractional picosecond laser could be widely applied in clinical settings where dermal regeneration and promotion of skin rejuvenation is required.

Efficacy of Fractional Carbon Dioxide (CO2) Laser versus Q-Switched Neodymium-Doped Yttrium Aluminum Garnet (Nd:YAG) and Potassium-Titanyl-Phosphate (KTP) Lasers in the Treatment of Acanthosis Nigricans

Background

Acanthosis nigricans (AN) is a common chronic skin disorder clinically presents by velvety hyperpigmented lesions mainly at the flexural areas. Fractional photothermolysis has been reported to improve both pigmentary and textural changes by removing thin layers of skin with minimal thermal damage. Other options are the Q-switched (Qs) Nd:YAG (1064 nm) and Qs KTP (532 nm) lasers. Both can induce collagen remodeling by dermal photo-mechanical microdamage.

Aim of the Work

The aim of this study was to assess the clinical efficacy and the safety of fractional CO₂ laser versus Qs Nd:YAG and KTP lasers in the treatment of acanthosis nigricans.

Methods

This randomized-controlled split neck study was conducted on 23 patients suffering from AN. For each patient, one side of the neck was randomly assigned to fractional CO₂ laser and the other side to Qs Nd:YAG and KTP lasers every four weeks for four months followed by 4 monthly follow-up assessment. Acanthosis Nigricans Area and Severity Index (ANASI) score, melanin and erythema indices as well as Patient Satisfaction Scale (PSS) were used to assess improvement on each side separately.

Results

There was no statistically significant difference regarding the clinical improvement between the side treated with Fractional CO₂ laser and the side treated with Qs Nd:YAG and KTP lasers (P value >0.05). In most patients, both sides showed improvement during different sessions of therapy, as regards ANASI scores, melanin indices, patient satisfaction scores, and side effects.

Conclusion

In this study, we concluded that both fractional CO₂ and Q-switched lasers proved to be a safe and effective line of treatment of acanthosis nigricans.

Q-Switched 1064 nm Nd:YAG Laser Rejuvenates Photoaging Skin of Rats by Downregulating miR-196b-5p

Background: Q-switched 1064 nm Nd:YAG laser (1064-QSNYL) is efficient in rejuvenating photoaging skin, and microRNAs (miRNAs) participate in this process. Objective: In this study, we aimed to explore the effects of 1064-QSNYL on miR-196b-5p, TGF-beta receptor II (TGFBR2), and SMAD7 in the photoaging skin of rats. Methods: The relationship between miR-196b-5p and TGFBR2 in HaCaT cells was detected by real-time PCR and western blotting. A skin photoaging model was established in Wistar rats using ultraviolet (UV) radiation (UVR). Dermoscopy, hematoxylin-eosin (HE) staining, Sirius red staining, and hydroxyproline content were used to observe the effect of UVR on rat skin. The 1064-QSNYL was used for skin rejuvenation. The expression of COL3A1, TGFB1, TGFBR2, SMAD2, SMAD3, and SMAD7 was detected by real-time PCR and/or western blotting. Results: TGFBR2 was a specific target of miR-196b-5p in the skin. In HaCaT cells and the photoaging skin of rats, 1064-QSNYL treatment upregulated COL3A1 and TGFBR2 and downregulated SMAD7 and miR-196b-5p. Conclusions: We showed for the first time that 1064-QSNYL treatment rejuvenates photoaging rat skin by regulating TGFBR2 and SMAD7. Downregulation of miR-196b-5p assists in this process by targeting and upregulating TGFBR2.

[Treatment and progress of cutaneous neurofibroma]

Objective

To summarize current widely-used therapies for cutaneous neurofibroma (cNF) and related research progress.

Methods

Based on extensive investigation of domestic and foreign research, the existing treatment of cNF, including the indications, effectiveness and trials of targeted drugs were reviewed.

Results

cNF is a hallmark feature of neurofibromatosis type 1 and has a dramatic negative impact on patient appearance and quality of life. At present, there is no standard management of cNF. Invasive treatment is a commonly-used treatment. Surgical removal gives excellent cosmetic results, but it is difficult for multiple tumors; CO2 laser ablation, laser photocoagulation, electro-drying, and radiofrequency ablation are effective in treating lots of cNF at one time. Although fast and effective, these therapies can lead to depigmentation, hyperpigmentation, or extensive scarring. There is no targeted drug approval for cNF, and a series of studies have been carried out on the Ras-MEK pathway, Ras-mTOR pathway, receptor tyrosine kinase, et al.

Conclusion

The treatment of cNF has developed rapidly in recent years and has broad prospects, but the individualization and precision of the treatment still needs further clinical research.

Rationale for 1068 nm Photobiomodulation Therapy (PBMT) as a Novel, Non-Invasive Treatment for COVID-19 and Other Coronaviruses: Roles of NO and Hsp70

Researchers from across the world are seeking to develop effective treatments for the ongoing coronavirus disease 2019 (COVID-19) outbreak, which arose as a major public health issue in 2019, and was declared a pandemic in early 2020. The pro-inflammatory cytokine storm, acute respiratory distress syndrome (ARDS), multiple-organ failure, neurological problems, and thrombosis have all been linked to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) fatalities. The purpose of this review is to explore the rationale for using photobiomodulation therapy (PBMT) of the particular wavelength 1068 nm as a therapy for COVID-19, investigating the cellular and molecular mechanisms involved. Our findings illustrate the efficacy of PBMT 1068 nm for cytoprotection, nitric oxide (NO) release, inflammation changes, improved blood flow, and the regulation of heat shock proteins (Hsp70). We propose, therefore, that PBMT 1068 is a potentially effective and innovative approach for avoiding severe and critical illness in COVID-19 patients, although further clinical evidence is required.

Treatment of melasma with a low-fluence 1064 nm Q-switched Nd:YAG laser: Laser toning in Caucasian women

BACKGROUND AND OBJECTIVES

Melasma is a common, therapeutically challenging, and very often relapsing disorder of hyperpigmentation most often observed in women. Low-fluence, multipass technique with Q-switched-mode laser-"laser toning" is broadly used to treat melasma, especially in Asia. The study aimed to evaluate the effects of a series of laser treatments with very short, nanosecond pulses in the treatment of melasma in Caucasian women.

MATERIAL AND METHODS

Forty polish females with Fitzpatrick skin phototype II-III and melasma were treated with 1064 nm Q-switched neodymium:yttrium-aluminum-garnet (QSNY) laser (pulse with 5 ns; spot size, 6-8 mm; fluence, 1.7-3.2 J/cm² ; 2-8 passes; nine treatments). Melanin index (MI), erythema index (EI) by Mexameter MX18®, the modified Melasma Area Severity Index (mMASI), and the participant's self-assessment were used to evaluate the treatment results. Twenty-one patients were subjected to a 1-year follow-up.

RESULTS

Significant improvement in melasma pigmentation was observed in the mean MI and mMASI score; both were significantly reduced (p < 0.0001). Significant erythema reduction was achieved (p < 0.001). In total, 70% of participants rated the laser as a method that met their expectations for treating melasma. Clinical follow-up after one year showed that the reduced melasma effect was still maintained. Patients also noticed improved skin conditions (radiance, smoothness, brightness, hydration, regeneration). No serious adverse effects were observed.

CONCLUSIONS

Low-fluence 1064 nm QSNY laser is an effective, safe, and noninvasive method with long-term results in melasma treatment. QSNY (1064 nm) improves the condition of melasma patients with erythema.

Effect of Different Wavelengths of Laser Irradiation on the Skin Cells

The invention of systems enabling the emission of waves of a certain length and intensity has revolutionized many areas of life, including medicine. Currently, the use of devices emitting laser light is not only an indispensable but also a necessary element of many diagnostic procedures. It also contributed to the development of new techniques for the treatment of diseases that are difficult to heal. The use of lasers in industry and medicine may be associated with a higher incidence of excessive radiation exposure, which can lead to injury to the body. The most exposed to laser irradiation is the skin tissue. The low dose laser irradiation is currently used for the treatment of various skin diseases. Therefore appropriate knowledge of the effects of lasers irradiation on the dermal cells’ metabolism is necessary. Here we present current knowledge on the clinical and molecular effects of irradiation of different wavelengths of light (ultraviolet (UV), blue, green, red, and infrared (IR) on the dermal cells.

The effect of Q-switched 1064-nm Nd: YAG laser on skin barrier and collagen synthesis via miR-663a to regulate TGFβ1/smad3/p38MAPK pathway

BACKGROUND

Our previous research found that Q-switched 1064-nm Nd: YAG laser (1064-QSNYL) induces skin collagen synthesis by activating TGFβ1/Smad3/p38MAPKs pathway. Moreover, a lot of studies shown that MicroRNAs (miRNAs) contribute to regulate collagen synthesis and skin barrier. Therefore, we intend to explore the mechanism of 1064-QSNYL on collagen synthesis and skin barrier through miRNAs.

METHODS

We predicted the upstream miRNAs of TGFβ1 by bioinformatics databases, and verified them through dual-luciferase reporter genes and Western blotting. The expression of collagen, skin barrier-related protein K10 and filaggrin, TIMP-1, and MMP-2 were detected by RT-qPCR and Western blotting, respectively. Moreover, we detected moisture content, elasticity value, TEWL value, SOD vitality, and hydroxyproline content to evaluate skin barrier of mice. H&E staining to observe the change of dermis thickness and inflammation and infiltration of mice skin.

RESULTS

The results shown that TGFβ1 was target gene of miR-663a. Moreover, we found that 1064-QSNYL activated TGFβ1/smad3/p38MAPK pathway by down-regulating the expression of miR-663a in HaCaT, HDF cells, and mice, thereby promoting expression of Collagen I, Collagen IV, TIMP-1, K10, and filaggrin and inhibiting MMP-2. Furthermore, 1064-QSNYL contributed to moisture content, elasticity, SOD vitality, and hydroxyproline content via miR-663a to activate TGFβ1/smad3/p38MAPK pathway.

CONCLUSIONS

In summary, this study found for the first time that 1064-QSNYL contributed to collagen synthesis and skin repair via miR-663a to regulate TGFβ1/smad3/p38MAPK pathway, thereby achieving skin rejuvenation.

Will Repeated Low-Energy 1064-nm Q-Switched Nd:YAG Laser Treatment Sessions Affect Facial Skin Sensitivity? Results of a 12-Month, Prospective, Randomized Split-Face Study

BACKGROUND AND OBJECTIVE

To compare changes in skin sensitivity before and after treatment with a 1064-nm Q-switched Nd:YAG laser in healthy individuals, and to provide a reference for clinicians to use this laser reasonably.

STUDY DESIGN/MATERIALS AND METHODS

Nineteen healthy female volunteers underwent 10 random unilateral 1064-nm Q-switched Nd:YAG laser treatments. The skin transepidermal water loss rate (TEWL), skin glossiness, epidermal and dermal thickness and density, current perception threshold (CPT) value, facial blood perfusion were determined before and after treatment at different time points. Moreover, the changes in skin barrier function, blood vessels, and sensory nerve reaction in the treated and untreated sides of the face were recorded before and after treatment.

RESULTS

Seventeen volunteers completed the 12-month follow-up study after 1064-nm Q-switched Nd:YAG laser treatment. At D3, M3, and M6, skin TEWL was decreased on the treated side of the face. Skin glossiness was significantly improved in the early post-treatment period (D1-D7) and M3, M6, and M12 compared with the untreated side of the face. There was no significant change in dermal and epidermal thickness or density at all time points before and after treatment. There were no significant differences in sensory nerve CPT values and local blood flow volume or velocity between the treated side of the face and the untreated side before and after treatment.

CONCLUSION

Multiple low-energy 1064-nm Q-switched Nd:YAG laser treatments will not affect the barrier function of facial skin, skin nerve sensitivity, or local microcirculation of healthy skin over the long term. Therefore, 1064-nm Q-switched Nd:YAG laser treatment is safe, and does not alter skin sensitivity. Lasers Surg. Med. © 2021 Wiley Periodicals LLC.

In Vitro Cytological Responses against Laser Photobiomodulation for Periodontal Regeneration

Periodontal disease is a chronic inflammatory disease caused by periodontal bacteria. Recently, periodontal phototherapy, treatment using various types of lasers, has attracted attention. Photobiomodulation, the biological effect of low-power laser irradiation, has been widely studied. Although many types of lasers are applied in periodontal phototherapy, molecular biological effects of laser irradiation on cells in periodontal tissues are unclear. Here, we have summarized the molecular biological effects of diode, Nd:YAG, Er:YAG, Er,Cr:YSGG, and CO₂ lasers irradiation on cells in periodontal tissues. Photobiomodulation by laser irradiation enhanced cell proliferation and calcification in osteoblasts with altering gene expression. Positive effects were observed in fibroblasts on the proliferation, migration, and secretion of chemokines/cytokines. Laser irradiation suppressed gene expression related to inflammation in osteoblasts, fibroblasts, human periodontal ligament cells (hPDLCs), and endothelial cells. Furthermore, recent studies have revealed that laser irradiation affects cell differentiation in hPDLCs and stem cells. Additionally, some studies have also investigated the effects of laser irradiation on endothelial cells, cementoblasts, epithelial cells, osteoclasts, and osteocytes. The appropriate irradiation power was different for each laser apparatus and targeted cells. Thus, through this review, we tried to shed light on basic research that would ultimately lead to clinical application of periodontal phototherapy in the future.

Q-switched Nd-YAG laser alone and in combination with innovative hyaluronic acid gels improve keratinocytes wound healing in vitro

During the last years, several attempts have been accomplished to improve the wound healing. Device application aimed at enhancing skin ability to reconstruct its damaged sites through a proper dermal regenerative process. In particular, Q-switched Nd-YAG laser (Medlite C6 laser, Conbio, USA) applied with a fluence of 8 J/cm², a pulse width of 5 ns, and a spot size of 4 mm exerts a photo-mechanical action that improve skin repair. Besides, hyaluronan hybrid cooperative complexes (HCC) widely exploited in dermoesthetic applications proved specific actions on keratinocytes and fibroblasts monolayer repair. We evaluated this specific laser treatment in vitro on a wound healing model based on human keratinocytes (HaCaT) alone and in combination with HCC. In addition, we evaluated key biomarkers of dermal repair. Scratched HaCaT monolayers were treated with laser and successively with HA-based formulations (HHA and HCC). For each treatment and the control samples, at least 3 different wells were analyzed. Wound closure was quantified, measuring five view filed for each well at increasing incubation time, exploiting time lapse videomicroscopy and image analysis, permitting to compare the different healing rate of treatments respect to control. By real-time PCR and western blotting, we evaluated biomarkers of wound regeneration, such as integrins, aquaporin three (AQP3), and proinflammatory cytokines. The ANOVA test was used to assess statistical significance of the results obtained. Laser-treated cells achieved wound closure in about 37 h, faster than the control, while when coupled to HCC, the complete reparation was obtained in 24 h. Integrin αV was upregulated by treatments, with in particular about four-fold increase respect to the control when HCC + laser was used. In addition, integrin β3 was upregulated by all treatments especially with the combination of laser and HCC proved more efficient than others (~ 14-folds). A slighter but significant increase of AQP3 gene expression of 61% was found for laser treatment while the latter combined with HCC determined an upregulation of 72%. By coupling laser treatment and HCC, further healing improvement and consistent biomarker modulation was observed. Our results may support clinical implementation of new dermatology protocols conjugating laser treatments with topical or injective HA formulations as a valid tool in treatments to repair scars or other skin defects.

Efficacy, safety, and guidelines of application of the fractional ablative laser erbium YAG 2940 nm and non-ablative laser erbium glass in rejuvenation, skin spots, and acne in different skin phototypes: a systematic review

Non-ablative and ablative fractional erbium lasers are among the most frequently used resources in dermatology for facial rejuvenation and for treating dermatological disorders. This type of erbium laser can be found at wavelengths of 1540 or 1550 nm, which are classified as non-ablative erbium glass, and at 2940 nm, classified as ablative erbium YAG. Despite the reports of their clinical benefits, few scientific studies have demonstrated the efficacy and safety of these lasers in the short or long term. In order to substantiate the effects, benefits, and safety of applying the erbium glass and erbium YAG lasers, a systematic review was carried out from August to December 2019 about studies published in the last 20 years. Randomized clinical trials in humans were considered that evaluated the efficacy, safety, and benefits of applying the fractional lasers erbium glass and erbium YAG to facial rejuvenation, skin spots, and atrophic acne scars. A total of 338 articles were identified; 76 articles remained after their titles and abstracts were read, and 42 articles were selected after removing the duplicates. After the articles were read in full, 17 of these articles were included in the systematic review (453 patients). The erbium glass and erbium YAG lasers seem promising in the short term, with minimal adverse effects; however, the long-term efficacy and safety still present limitations. Consequently, future research is needed, with better methodological standardization and a follow-up with a longer evaluation period for possible permanent adverse effects to determine the standardization and safety of therapy with erbium glass and erbium YAG lasers.

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.