Combination of medicinal honey and 904 nm superpulsed laser-mediated photobiomodulation promotes healing and impedes inflammation, pain in full-thickness burn

The combined treatment of gold nanoparticles associated with photobiomodulation accelerate the healing of dermonecrotic lesion

Introduction: The search for fast and efficient treatment for dermonecrotic lesions caused by the venom of the spider from the Loxosceles simillis, is a demand in health. Prednisolone is one of the most used drugs, however it has side effects. In this context, addictionally gold nanoparticles (GNPs) have anti-inflammatory, antioxidant, and antibacterial properties. The use of photobiomodulation has show to be efficient in the process of tissue repair. Therefore, the purpose of this study was to investigate the anti-inflammatory effect of photobiomodulation and GNPs associated or not with a low concentration of prednisolone in animal models of dermonecrotic lesion.Methodology: For this, rabbits with venon-induced dermonecrotic lesion were subjected to topical treatment with prednisolone + laser or GNPs + laser or Pred-GNPs + laser. The area of edema, necrosis and erythema were measured. On the last day of treatment, the animals were euthanized to remove the organs for histopathological and biochemical analysis.Results: All treatments combinations were effective in promoting the reduction of necrotic tissue and erythema.Conclusion: With this results, we suggest that the use of laser and nanoparticles, associated or not with prednisolone, should be considered for the treatment of dermonecrotic injury.

Tailoring photobiomodulation to enhance tissue regeneration

Photobiomodulation (PBM), the use of biocompatible tissue-penetrating light to interact with intracellular chromophores to modulate the fates of cells and tissues, has emerged as a promising non-invasive approach to enhancing tissue regeneration. Unlike photodynamic or photothermal therapies that require the use of photothermal agents or photosensitizers, PBM treatment does not need external agents. With its non-harmful nature, PBM has demonstrated efficacy in enhancing molecular secretions and cellular functions relevant to tissue regeneration. The utilization of low-level light from various sources in PBM targets cytochrome c oxidase, leading to increased synthesis of adenosine triphosphate, induction of growth factor secretion, activation of signaling pathways, and promotion of direct or indirect gene expression. When integrated with stem cell populations, bioactive molecules or nanoparticles, or biomaterial scaffolds, PBM proves effective in significantly improving tissue regeneration. This review consolidates findings from in vitro, in vivo, and human clinical outcomes of both PBM alone and PBM-combined therapies in tissue regeneration applications. It encompasses the background of PBM invention, optimization of PBM parameters (such as wavelength, irradiation, and exposure time), and understanding of the mechanisms for PBM to enhance tissue regeneration. The comprehensive exploration concludes with insights into future directions and perspectives for the tissue regeneration applications of PBM.

Low-level laser activates Wnt/β-catenin signaling pathway-promoting hair follicle stem cell regeneration and wound healing: Upregulate the expression of key downstream gene Lef 1

BACKGROUND

The objective of this study is to investigate the mechanism by which low-level laser stimulation promotes the proliferation of intraepithelial hair follicle stem cells (HFSCs) in wounds. This research aims to expand the applications of laser treatment, enhance wound repair methods, and establish a theoretical and experimental foundation for achieving accelerated wound healing.

METHODS

The experimental approach involved irradiating a cell model with low-level laser to assess the proliferation of HFSCs and examine alterations in the expression of proteins related to the Wnt/β-catenin signaling pathway. A mouse back wound model was established to investigate the effects of low-level laser irradiation on wound healing rate, wound microenvironment, and the proliferation of HFSCs in relation to the Wnt/β-catenin signaling pathway.

RESULTS

The research findings indicate that low-level laser light effectively activates the Wnt signaling pathway, leading to the increased accumulation of core protein β-catenin and the upregulation of key downstream gene Lef 1. Consequently, this regulatory mechanism facilitates various downstream biological effects, including the notable promotion of HFSC proliferation and differentiation into skin appendages and epithelial tissues. As a result, the process of wound healing is significantly accelerated.

CONCLUSION

Low levels of laser activates the Wnt signalling pathway, promotes the regeneration of hair follicle stem cells and accelerates wound healing.

Honey therapies for dermatological disorders: more than just a sweet elixir

Honey possesses antibacterial, anti-inflammatory, and healing properties that benefit wound healing and tissue regeneration. For centuries, honey has been utilized in traditional medicine as a binder or vehicle for creams and lotions and also for therapeutic purposes. The overuse of antibiotics and antimicrobial agents leading to drug resistance has emphasized the resurgence of honey's application in wound care. For many dermatological disorders, there is an interest in developing therapeutics with fewer side effects than traditional therapies and enhanced wound healing abilities to expedite tissue regeneration. This paper reviews the properties and components of honey that contribute to its wound-healing-based applications, the types of honey employed in medicine, and its dermatological applications. Based on the evidence from case reports, clinical trials, and in vitro studies, honey has been characterized as a safe, cost-effective, and readily available treatment option for many skin conditions, including microbial infections, atopic dermatitis, psoriasis, necrotizing fasciitis, ulcers, as well as thermal and other types of wounds.

Estudo pré-clínico de queimaduras experimentais tratadas com fotobiomodulação e membrana amniótica humana, isoladas e associadas

Resumo Objetivo: avaliar o efeito da fotobiomodulação com laser de baixa intensidade 660 nm isoladamente ou associada à membrana amniótica humana no reparo de queimaduras de espessura parcial em ratos. Método: estudo experimental com 48 ratos Wistar machos, randomizados em quatro grupos: Controle, Membrana Amniótica Humana, Terapia a Laser de Baixa Intensidade e Terapia a Laser de Baixa Intensidade associado à Membrana Amniótica Humana. As características histopatológicas das amostras de pele foram analisadas aos 7 e 14 dias após a queimadura. Os dados obtidos foram submetidos aos testes de Kolmogorov-Smirnov e Mann Whitney. Resultados: a análise histológica das lesões por queimadura mostrou a diminuição da inflamação (p <0,0001) e aumento da proliferação de fibroblastos (p <0,0001), principalmente nos 7 dias em todos os tratamentos relacionados ao grupo controle. Aos 14 dias, a maior efetividade na aceleração do processo cicatricial foi significativa (p<0,0001) no grupo Terapia a Laser de Baixa Intensidade associado à Membrana Amniótica Humana. Conclusão: a associação das terapias de fotobiomodulação à membrana amniótica humana permitiu comprovar redução no tempo do processo cicatricial das lesões experimentais, estimulando sua proposição como protocolo de tratamento em queimaduras de espessura parcial.

Estudio preclínico de quemaduras experimentales tratadas con fotobiomodulación y membrana amniótica humana, solas y combinadas

Resumen Objetivo: evaluar el efecto de la fotobiomodulación con láser de baja intensidad 660 nm de sola o combinada con la membrana amniótica humana en la reparación de quemaduras de espesor parcial en ratas. Método: estudio experimental con 48 ratas Wistar macho, aleatorizadas en cuatro grupos: Control, Membrana Amniótica Humana, Terapia con Láser de Baja Intensidad y Terapia con Láser de Baja Intensidad combinada con la Membrana Amniótica Humana. Las características histopatológicas de las muestras de piel fueron analizadas a los 7 y 14 días después de la quemadura. Los datos obtenidos fueron sometidos a las pruebas de Kolmogorov-Smirnov y Mann-Whitney. Resultados: el análisis histológico de las lesiones por quemadura mostró una disminución de la inflamación (p <0,0001) y un aumento de la proliferación de fibroblastos (p <0,0001) principalmente a los 7 días en todos los tratamientos en comparación con el grupo control; a los 14 días, en el grupo de Terapia con Láser de Baja Intensidad combinada con la Membrana Amniótica Humana la mayor efectividad en la aceleración del proceso de cicatrización fue significativa (p<0,0001). Conclusión: la asociación de terapias de fotobiomodulación con la membrana amniótica humana permitió comprobar que hubo una reducción en el tiempo del proceso de cicatrización de lesiones experimentales, lo cual favorece que se proponga como protocolo de tratamiento en quemaduras de espesor parcial.

Bibliometric Analysis to Global Research Status Quo on Photobiomodulation

Background: Photobiomodulation (PBM) becomes a remedial technology with growing popularity. The primary goal of this article is to conduct a PBM literature review, providing an overall systematic understanding of current and future trends. Methods: A dataset was made with topic retrieval, concerning PBM research retrieved from the Web of Science Core Collection. We analyzed to forecast research frontiers in this field using the softwares: VOSviewer, CiteSpace, and Biblioshiny. Results: Four thousand five hundred thirty pieces of literature were retrieved from our database. Current trends were characterized by keywords of "light," "spinal cord injury," "skeletal muscle," and so on. Future trends were characterized probably by six cutting-edge terms: "wound healing," "pain," "oral mucositis," "Alzheimer's disease," "Parkinson's disease," and "orthodontics." Conclusions: This study finds that the inadequacy of in-depth reliable interpretation of current clinical data calls for molecular biological mechanisms together with well-designed, large-sample, multicenter clinical trials. The study of oral, wound, and neural-related mechanisms and the exploration of therapeutic effects may be the popular trend at present and in the next few years.

Effect of combination of photobiomodulation 904 nm superpulsed laser therapy and Hippophae rhamnoides L. on third-degree burn wound healing

BACKGROUND

Burn is a traumatic injury and aesthetic scarless repair poses a great challenge in area of cosmetic dermatology. Focus on multimode therapeutic strategies to promote healing of burns by regulating various stages of healing is warranted. Photobiomodulation therapy (PBMT), a non-invasive modality grabs the attention to repair impaired wounds. Seabuckthorn extract (SBTL-ALE) is known to possess antioxidant, anti-inflammation, and tissue-repair abilities. Current study aims to assess the effect of combination treatment of PBM 904 nm superpulsed laser and SBTL-ALE (2.5%) on repair of third-degree burn in rats.

METHODS

Rats were randomized into five groups: uninjured, control, SBTL-ALE, 904 nm PBMT, and combination. A transdermal burn wound was induced on the dorsal side of rats of all groups except the uninjured group and respective treatment was applied for 7 days postwounding.

RESULTS

Dual treatment increased wound area contraction compared to control and either treatment alone. Immunohistochemical analyses exhibited increased angiogenesis, dermal hydration, collagen synthesis, and maintained redox homeostasis as evidenced by enhanced expression (p < 0.05) of CD31, aquaporin3, collagen type 3, Nrf2, and HO1 in combination group compared with control. Conversely, pro-inflammatory and oxidative stress markers exhibited reduced (p < 0.05) TNF-α, IL-6, IL-1β, NOS-2, ROS levels, and increased catalase activity in combined treatment. Furthermore, energy metabolizing enzymes viz. citrate synthase, CCO, and ATP contents were substantially (p < 0.05) increased, and LDH activity was reduced in the combination group.

CONCLUSIONS

Dual treatment (PBMT + SBTL-ALE) prominently accelerates third-degree burn wound healing in rats, which could pave the path for multimode therapeutic strategies for the management of burns and dermal cosmetic care.

Wound contraction rate in excised and unexcised burn wounds with laser photobiomodulation: Systematic review and meta-analysis of preclinical studies

INTRODUCTION

Laser photobiomodulation (laser PBM) is an effective means of accelerating burn wound contraction, however it is still unclear whether laser PBM produces greater benefit when applied directly to excised and unexcised burn wounds . The aim of this systematic review of preclinical studies was to determine the effectiveness of laser PBM in the wound contraction rate in excised and unexcised burn wounds.

MATERIALS AND METHODS

A systematic search was conducted in the EMBASE, MEDLINE and LILACS databases. Preclinical studies were included that analysed the effectiveness of laser PBM in burn wound contraction, and assessed wound closure. The SYRCLE risk of bias tool was used. Random effects models were used to estimate the pooled effect.

RESULTS

Thirteen studies were included in the qualitative analysis and six in the quantitative analysis. Two weeks after the lesion, laser PBM favoured the wound contraction percentage, increasing the closure rate in excised burn wounds (SMD= 1.34, CI 95% 0.41 to 2.27, 0.41-2.27, I²=0%, =0%, low certainty of evidence. In unexcised burns, it was uncertain whether laser PBM increased or diminished the wound contraction rate (SMD=1.22(SMD=1.22 CI 95% -0.05 to 2.49, I²=68%; =68%; very low certainty of evidence).

CONCLUSIONS

In the animal model, laser PBM is effective in increasing the wound contraction rate in excised burns. However, due to the low certainty of the evidence, uncertainty remains about the true magnitude of the effect of laser on wound contraction in animals; our results should therefore be interpreted with caution.

Photomodulative effects of low-level laser therapy on tracheal fenestration developed in in vivo model

The effect of low-level laser therapy (LLLT) on variable mucosal lesions in the upper aerodigestive tract has been reported. However, the effect of LLLT on tracheostomy sites or tracheal fenestration is rarely reported. In this study, we evaluate the effect of LLLT performed using 635 nm laser light based on a cylindrical diffuser and an animal model with tracheal fenestration. An animal model of tracheal fenestration is developed by suturing the trachea to the skin after performing a vertical tracheostomy from the second to the fifth tracheal ring of Wistar rats (male, body weight 200-250 g). LLLT (spot size: 2 cm²) is conducted once daily for five days using a handheld cylindrical device. Twenty-four rats are randomly assigned to a no-therapy or LLLT group with an energy density of 20 J/cm². Histological analysis is performed at 7 and 14 days after tracheal fenestration. Irradiation at the tracheal fenestration site with an energy density of 20 J/cm² improves the wound healing, as shown at 2 weeks after tracheostomy. Histological analysis shows significantly decreased acute inflammation and granulation tissue, as well as better cartilage regeneration and less tracheal wall thickening. Therefore, LLLT demonstrates therapeutic potential for preventing tracheal stenosis and granuloma after tracheostomy.

Preclinical study of experimental burns treated with photobiomodulation and Human Amniotic Membrane, both isolated and associated

OBJECTIVE

to evaluate the effect of photobiomodulation with low-level 660 nm laser alone or associated with Human Amniotic Membrane in the repair of partial-thickness burns in rats.

METHOD

an experimental study conducted with 48 male Wistar rats, randomized into four groups: Control, Human Amniotic Membrane, Low-Level Laser Therapy, and Low-Level Laser Therapy associated with Human Amniotic Membrane. The histopathological characteristics of the skin samples were analyzed 7 and 14 days after the burn. The data obtained were submitted to the Kolmogorov-Smirnov and Mann-Whitney tests.

RESULTS

the histological analysis of the burn injuries showed a decrease in inflammation (p<0.0001) and an increase in proliferation of fibroblasts (p<0.0001) mainly at 7 days in all treatments related to the control group. At 14 days, the greater effectiveness in accelerating the healing process was significant (p<0.0001) in the Low-Level Laser Therapy group associated with the Human Amniotic Membrane.

CONCLUSION

the association of photobiomodulation therapies with the Human Amniotic Membrane allowed verifying a reduction in the healing process time of the experimental lesions, stimulating its proposal as a treatment protocol in partial-thickness burns.

Antibacterial Efficacy and Healing Potential of Honey from Different Zones in Nigeria on Diabetic-Induced Wound Infection in Wistar Rats

There is an increase in drug-resistant strains causing infection, thus making available therapeutics less effective. As resistance increases, modern medicine focuses on the antibacterial potential of natural products, which can aid in wound healing. The present study determined Nigeria honey's antibacterial efficacy in treating diabetes-induced wound infections in Wistar albino rats. 54 Wistar rats randomly divided into 9 groups of 6 each were used for the study: group I (negative control, no treatment), group II (positive control, diabetes without treatment), group III (diabetes treated with 1% silver sulfadiazine), and groups IV–IX (diabetes treated with different honey samples). Physiochemical analysis and microbiological and antibacterial activity of the honey samples were determined. The treatments were carried out for 17 days, and wound contraction, malondialdehyde (MDA) levels, and catalase activity were measured. Results obtained showed that the most effective honey was DCH (21.5 ± 2.12), followed by HBP + M (15 ± 2.12) and TRB, JS, and HBP (13 ± 2.8; 13 ± 1.41; 13.5 ± 0.71) for antibacterial activity on Staphylococcus aureus. Microbiologically, no coliform was detected in all the samples, confirming the honey's quality. The amount of lipid peroxidation was raised in the diabetic group with no treatment, 1% silver sulfadiazine group, and JS group, while no significant reduction was observed in other groups. Differences in wound contraction were significantly notable on various days of measurement, day 3 (p < 0.002), day 6 (p < 0.046), and day 9 (p = 0.00). The catalase level in the different treatment groups increased significantly (p < 0.05), implying an antioxidant potential of the different honey samples except for Jos honey. The study concludes that honey infused with moringa was faster and more efficient in healing diabetic wounds than other honey samples and silver sulfadiazine.

The potential application of natural products in cutaneous wound healing: A review of preclinical evidence

Under normal circumstances, wound healing can be summarized as three processes. These include inflammation, proliferation, and remodeling. The vast majority of wounds heal rapidly; however, a large percentage of nonhealing wounds have still not been studied significantly. The factors affecting wound nonhealing are complex and diverse, and identifying an effective solution from nature becomes a key goal of research. This study aimed to highlight and review the mechanisms and targets of natural products (NPs) for treating nonhealing wounds. The results of relevant studies have shown that the effects of NPs are associated with PI3K-AKT, P38MAPK, fibroblast growth factor, MAPK, and ERK signaling pathways and involve tumor growth factor (TNF), vascular endothelial growth factor, TNF-α, interleukin-1β, and expression of other cytokines and proteins. The 25 NPs that contribute to wound healing were systematically summarized by an inductive collation of the six major classes of compounds, including saponins, polyphenols, flavonoids, anthraquinones, polysaccharides, and others, which will further direct the attention to the active components of NPs and provide research ideas for further development of new products for wound healing.

Role of Honey in Advanced Wound Care

Honey is a natural product rich in several phenolic compounds, enzymes, and sugars with antioxidant, anticarcinogenic, anti-inflammatory, and antimicrobial potential. Indeed, the development of honey-based adhesives for wound care and other biomedical applications are topics being widely investigated over the years. Some of the advantages of the use of honey for wound-healing solutions are the acceleration of dermal repair and epithelialization, angiogenesis promotion, immune response promotion and the reduction in healing-related infections with pathogenic microorganisms. This paper reviews the main role of honey on the development of wound-healing-based applications, the main compounds responsible for the healing capacity, how the honey origin can influence the healing properties, also highlighting promising results in in vitro and in vivo trials. The challenges in the use of honey for wound healing are also covered and discussed. The delivery methodology (direct application, incorporated in fibrous membranes and hydrogels) is also presented and discussed.

Photobiomodulation Therapy in Burn Wound Healing: Systematic Review and Meta-Analysis of Preclinical Studies

Background and objective: To determine the effectiveness of photobiomodulation therapy (PBMT) in the burn wound healing compared with the control or with the use of antibiotics, in animal models. Materials and methods: A systematic search was conducted in EMBASE, MEDLINE, and LILACS databases. Preclinical studies were included that analyzed the effectiveness of PBMT in the burn wound healing, which assessed wound contraction, angiogenesis, proliferation of fibroblasts, and collagen deposition. SYRCLE risk of bias tool was used. Random effects models were used to estimate the pooled effect. Results: Thirty-eight studies were included. PBMT favored wound contraction (mean difference = -11.47, 95% confidence interval -19.87 to -3.08, I² = 0%; moderate certainty of evidence). PBMT also favored angiogenesis at doses between 11 and 20 J/cm², and increased the collagenization rate. Conclusions: In animal models, PBMT favored wound contraction, angiogenesis, and collagen deposition in second- and third-degree burn wounds.

Mechanisms and Pathways of Pain Photobiomodulation: A Narrative Review

A growing body of evidence supports the modulation of pain by light exposure. As such, phototherapy is being increasingly utilized for the management of a variety of pain conditions. The modes of delivery, and hence applications of phototherapy, vary by wavelength, intensity, and route of exposure. As such, differing mechanisms of action exist depending upon those parameters. Cutaneous application of red light (660 nm) has been shown to reduce pain in neuropathies and complex regional pain syndrome-I, whereas visual application of the same wavelength of red light has been reported to exacerbate migraine headache in patients and lead to the development of functional pain in animal models. Interestingly visual exposure to green light can result in reduction in pain in variety of pain conditions such as migraine and fibromyalgia. Cutaneous application typically requires exposure on the order of minutes, whereas visual application requires exposure on the order of hours. Both routes of exposure elicit changes centrally in the brainstem and spinal cord, and peripherally in the dorsal root ganglia and nociceptors. The mechanisms of photobiomodulation of pain presented in this review provide a foundation in furtherance of exploration of the utility of phototherapy as a tool in the management of pain. PERSPECTIVE: This review synopsizes the pathways and mechanisms through which light modulates pain and the therapeutic utility of different colors and exposure modalities of light on pain. Recent advances in photobiomodulation provide a foundation for understanding this novel treatment for pain on which future translational and clinical studies can build upon.

Accelerated burn wound healing with photobiomodulation therapy involves activation of endogenous latent TGF-β1

The severity of tissue injury in burn wounds from associated inflammatory and immune sequelae presents a significant clinical management challenge. Among various biophysical wound management approaches, low dose biophotonics treatments, termed Photobiomodulation (PBM) therapy, has gained recent attention. One of the PBM molecular mechanisms of PBM treatments involves photoactivation of latent TGF-β1 that is capable of promoting tissue healing and regeneration. This work examined the efficacy of PBM treatments in a full-thickness burn wound healing in C57BL/6 mice. We first optimized the PBM protocol by monitoring tissue surface temperature and histology. We noted this dynamic irradiance surface temperature-monitored PBM protocol improved burn wound healing in mice with elevated TGF-β signaling (phospho-Smad2) and reduced inflammation-associated gene expression. Next, we investigated the roles of individual cell types involved in burn wound healing following PBM treatments and noted discrete effects on epithelieum, fibroblasts, and macrophage functions. These responses appear to be mediated via both TGF-β dependent and independent signaling pathways. Finally, to investigate specific contributions of TGF-β1 signaling in these PBM-burn wound healing, we utilized a chimeric TGF-β1/β3 knock-in (TGF-β1^Lβ3/Lβ3) mice. PBM treatments failed to activate the chimeric TGF-β1^Lβ3/Lβ3 complex and failed to improve burn wound healing in these mice. These results suggest activation of endogenous latent TGF-β1 following PBM treatments plays a key role in burn wound healing. These mechanistic insights can improve the safety and efficacy of clinical translation of PBM treatments for tissue healing and regeneration.

Honey Combination Therapies for Skin and Wound Infections: A Systematic Review of the Literature

Topical application of medical grade honey is recommended for the clinical management of wound infections. The suitability of honey as a wound healing agent is largely due to its antibacterial activity, immune modulatory properties, and biocompatibility. Despite the usefulness of honey in wound healing, chronic wound infections continue to be a global problem requiring new and improved therapeutic interventions. Several recent studies have investigated the effects of combining honey with other therapies or agents with the aim of finding more efficacious treatments. In this systematic review, the database PubMed was used to carry out a search of the scientific literature on the combined effects of honey and other therapies on antimicrobial activity and wound and skin healing. The search revealed that synergistic or additive antimicrobial effects were observed in vitro when honey was combined with antibiotics, bacteriophages, antimicrobial peptides, natural agents, eg, ginger or propolis and other treatment approaches such as the use of chitosan hydrogel. Outcomes depended on the type of honey, the combining agent or treatment and the microbial species or strain. Improved wound healing was also observed in vivo in mice when honey was combined with laser therapy or bacteriophage therapy. More clinical studies in humans are required to fully understand the effectiveness of honey combination therapies for the treatment of skin and wound infections.

Selective Laser Efficiency of Green-Synthesized Silver Nanoparticles by Aloe arborescens and Its Wound Healing Activities in Normal Wounded and Diabetic Wounded Fibroblast Cells: In vitro Studies

Introduction

Silver nanoparticles (AgNPs) have been extensively used in wound healing applications owing to their valuable physicochemical and biological properties. The main objective of this study was to evaluate the combined effects of green-synthesized silver nanoparticles (G-AgNPs) and photobiomodulation (PBM; laser irradiation at 830 nm with 5 J/cm²) in normal wounded and diabetic wounded fibroblast cells (WS1).

Methods

The combined effect of G-AgNPs and PBM was studied by various in vitro wound healing studies including cell morphology, cell migration rate and percentage wound closure, cell viability, cell proliferation, and filamentous (F)-actin and nuclear morphology staining.

Results

Cell viability results revealed good cellular compatibility of G-AgNPs to WS1 cells. The combined therapy of G-AgNPs and PBM demonstrated promising results to achieve progressive migration and wound closure in both normal wounded and diabetic wounded cell models. G-AgNPs alone and in combination with PBM had no negative effect on cell viability and proliferation, and there was an increase in cell migration.

Conclusion

Overall, these findings demonstrate that the combined treatment of G-AgNPs and PBM does not display any adverse effects on wound healing processes in both normal wounded and diabetic wounded cell models.

Effects of the Association between Photobiomodulation and Hyaluronic Acid Linked Gold Nanoparticles in Wound Healing

Healing is the process responsible for restoring the integrity of the body's internal or external structures when they rupture. Photobiomodulation (PBM) stands out as one of the most efficient resources in the treatment of epithelial lesions, as well as hyaluronic acid (HA), which has been emerging as a new molecule for the treatment of dermal and epidermal lesions. The biological application of gold nanoparticles (GNPs) shows promising results. This study aimed to investigate the possible anti-inflammatory and antioxidant effects of the association between PBM and GNPs-linked HA in an epithelial lesion model. Fifty Wistar rats were randomly distributed in the Control Group (CG); (PBM); (PBM + HA); (PBM + GNPs); (PBM + GNPs-HA). The animals were anesthetized, trichotomized, and induced to a surgical incision in the dorsal region. Topical treatment with HA (0.9%) and/or GNPs (30 mg/kg) occurred daily associated with 904 nm laser irradiation, dose of 5 J/cm², which started 24 h after the lesion and was performed daily until the seventh day. The levels of proinflammatory (IL1 and TNFα), anti-inflammatory (IL10 and IL4) and growth factors (FGF and TGFβ) cytokines and oxidative stress parameters were evaluated, besides histological analysis through inflammatory infiltrate, fibroblasts, new vessels, and collagen production area. Finally, for the analysis of wound size reduction, digital images were performed and subsequently analyzed by the IMAGEJ software. The treated groups showed a decrease in proinflammatory cytokine levels and an increase in anti-inflammatory cytokines. TGFβ and FGF levels also increased in the treated groups, especially in the combination therapy group (PBM + GNPs-HA). Regarding the oxidative stress parameters, MPO, DCF, and Nitrite levels decreased in the treated groups, as well as the oxidative damage (Carbonyl and Thiol groups). In contrast, antioxidant defense increased in the groups with the appropriate therapies proposed compared to the control group. Histological sections were analyzed where the inflammatory infiltrate was lower in the PBM + GNPs-HA group. The number of fibroblasts was higher in the PBM and PBM + HA treated groups, whereas collagen production was higher in all treated groups. Finally, in the analysis of the wound area contraction, the injury group presented a larger area in cm² compared to the other groups. Taken together, these results allow us to observe that the combination of PBM + GNPs-HA optimized the secretion of anti-inflammatory cytokines, proliferation and cell differentiation growth factors, and made an earlier transition to the chronic phase, contributing to the repair process.

Photobiomodulation therapy improves the growth factor and cytokine secretory profile in human type 2 diabetic fibroblasts

Impaired wound healing is a common complication of diabetes mellitus (DM) and the underlying mechanism of this impairment is still unclear. Fibroblast, as the main reconstructing cell, secretes some critical growth factors and cytokine contributing to wound healing. It is well known that DM alters the behavior of these cells and photobiomodulation therapy (PBMT) compensates some impairments in diabetic fibroblasts. Therefore, the aim of the present study was to demonstrate the impact of diabetes and the role of PBMT through low level laser irradiation on secretory profile of human diabetic fibroblasts. Primary human dermal fibroblasts from normal (HDFs) and diabetic (DHDFs) donors were harvested. For PBMT, the DHDFs were irradiated with a Helium-Neon laser at 632.8 nm wavelength and energy density of 0.5 J/cm², as laser treated group (LT-DHDFs). Next, some cellular behaviors and secretory profiling array for 60 growth factors/cytokines were investigated in LT-DHDFs and then compared with those of controls. The data showed that the PBMT could compensate such impairments occurred in DHDFs in terms of viability, proliferation, and migration. Furthermore, considering our novel findings, out of those 20 growth factors/cytokines involved in cell proliferation, immune system regulation, and cell-cell communication pathways, which significantly decreased in DHDF as compared with HDFs, the PBMT could compensate seven in LT-DHDFs as compared with DHDFs. The seven growth factor/cytokines, which are mainly involved in cell-cell communication, positive regulation of cell proliferation, and chemokine mediated pathway included BDNF, Eotaxin-3, FGF6, FGF7, Fractalkine, fit-3ligand, and GCP-2. Therefore, it is suggested that scrutinizing these differentially secreted molecules and the impaired pathways in DHDFs, in combination with those compensated in LT-DHDFs, could raise our knowledge to manage diabetic ulcer through a feasible and cost effective intervention, specifically PBMT.

Role of 904 nm superpulsed laser-mediated photobiomodulation on nitroxidative stress and redox homeostasis in burn wound healing

BACKGROUND

Burn wound healing is delayed due to several critical factors such as sustained inflammation, vascular disorder, neuropathy, enhanced proteolysis, infection, and oxidative stress. Burn wounds have limited oxygen supply owing to compromised blood circulation. Hypoxic burn milieu leads to free radicals overproduction incurring oxidative injury, which impedes repair process causing damage to cell membranes, proteins, lipids, and DNA. Photobiomodulation (PBM) with 904 nm superpulsed laser had shown potent healing efficacy via attenuating inflammation while enhancing proliferation, angiogenesis, collagen accumulation, and bioenergetic activation in burn wounds.

METHODS

This study investigated the effects of 904 nm superpulsed laser at 0.4 mW/cm² average power density, 0.2 J/cm² total energy density, 100 Hz frequency, and 200 ns pulse width for 10 min daily for seven days postburn injury on nitroxidative stress, endogenous antioxidants status, and redox homeostasis.

RESULTS

Photobiomodulation treatment significantly decreased reactive oxygen species, nitric oxide, and lipid peroxidation levels as compared to non-irradiated control. Further, protective action of PBM against protein oxidative damage was evidenced by reduced protein carbonylation and advanced oxidation protein product levels along with significantly enhanced endogenous antioxidants levels of SOD, catalase, GPx, GST, reduced glutathione, and thiol (T-SH, Np-SH, P-SH). Biochemical changes aid in reduction of oxidative stress and maintenance of redox homeostasis, which further well corroborated by significantly up-regulated protein expression of Nrf 2, hemeoxygenase (HO-1), and thioredoxin reductase 2 (Txnrd2).

CONCLUSION

Photobiomodulation with 904 nm superpulsed laser led to reduction of nitroxidative stress, induction of endogenous antioxidants, and maintenance of redox homeostasis that could play a vital role in augmentation of burn wound healing.

An active domain HF-18 derived from hagfish intestinal peptide effectively inhibited drug-resistant bacteria in vitro/vivo

Antibiotic resistance is spreading faster than the development of new antibiotics into clinical practice. Currently, the design of antimicrobial peptides (AMPs), potential new antibacterial agents with rare antimicrobial resistance, is the available strategy to enhance the antimicrobial activity and lower the toxicity of AMPs. In this study, a peptide derived from hagfish intestinal peptide was designed and termed as HF-18 (GFFKKAWRKVKKAFRRVL). After antimicrobial/bactericidal test in vitro, we found that HF-18 exhibited a potent antimicrobial activity with MIC of only 4 μg/ml against drug-resistant Staphylococcus aureus (S. aureus). Meanwhile, it eliminated the test bacteria within 1 h, suggesting its rapid bactericidal effect. Importantly, this peptide had no obvious hemolytic activity and cytotoxicity to mammalian cells. Furthermore, its notable antimicrobial effects in vivo was confirmed again in S. aureus induced mouse bacteremia and skin wound infection, reflecting as the decrease in bacterial counts in mouse lung or skin (up to 1.9 or 3.5 log CFU respectively), and including the inhibitory activity on inflammatory cytokines secretion. The possible mechanisms underlying HF-18 against drug-resistant S. aureus may attribute that HF-18 neutralized the negative charge in S. aureus surface and then disrupted the integrity of cell membranes to enhance the permeation of bacterial membrane, showing as the increased uptake of NPN and PI and the obvious morphology changes of S. aureus. In addition, this peptide bound to bacterial genomic DNA to suppress the expression of Panton-Valentine leukocidin (pvl) and nuclease (nuc) genes, which play major roles in S. aureus virulence. The properties of HF-18 suggest a path towards developing antibacterial agents that has stronger antibacterial activity and greater security for clinical treatment of infection induced by S. aureus, especially drug-resistant S. aureus.

Effects of a single treatment with two nonthermal laser wavelengths on chronic neck and shoulder pain

Introduction

Nonthermal lasers provide pain relief for a variety of musculoskeletal disorders and improve physical functioning. A nonthermal laser that employs a 635 nm red diode is cleared for the temporary reduction of neck and shoulder pain of musculoskeletal origin. As a 405 nm violet laser has shown synergy with the 635 nm red laser when used together for treating other conditions, the objective of this study was to compare the efficacy of 635 nm red and 405 nm violet lasers vs the 635 nm red laser for treating neck and shoulder pain of musculoskeletal origin.

Materials and methods

Otherwise healthy adult subjects with chronic neck or shoulder pain for ≥30 days were enrolled and randomized to receive a single 13-min treatment with combined red and violet lasers (n=44) or the red laser alone (n=43). The primary efficacy measure was change in baseline VAS pain scores 3 mins after treatment. Subject success was predefined as a ≥30% decrease in VAS scores and study success was predefined as 65±5% individual subject successes.

Results

Among subjects treated with the red and violet lasers, mean VAS neck and shoulder pain scores decreased from 65.0 to 35.2 (p<0.0001). Most subjects in the study (75%) achieved ≥30% decrease in VAS scores. The decreased mean (SD) VAS scores remained 29.6 (16.7) and 29.3 (19.2) after 24 and 48 hrs, respectively. The secondary efficacy measures of change in range of motion ROM) and patient satisfaction also improved. There were no adverse events.

Conclusion

Overall, treatment with the red and violet lasers outperformed the FDA-approved red laser with respect to change in pain scores and improvement in shoulder ROM.

Effects of Pulsed 810 nm Al-Ga-As Diode Laser on Wound Healing Under Immunosuppression: A Molecular Insight

BACKGROUND AND OBJECTIVES

Dysregulated inflammation is one of the major contributing factors for the prevalence of non-healing chronic wound in immunosuppressed subjects. Photobiomodulation (PBM) has emerged as a potential non-thermal, light-based therapeutic healing intervention for the treatment of impaired wounds.

STUDY DESIGN/MATERIALS AND METHODS

The present study delineates the underlying molecular mechanisms of PBM 810 nm laser-induced full-thickness cutaneous wound repair in immunosuppressed rats at continuous and pulsed wave-mode with power-density of 40 mW/cm ² , fluence 22.6 J/cm ² for 10 minutes daily for 7 post-wounding days. Molecular markers were assessed using biochemical, enzyme-linked immunosorbent assay quantification, enzyme kinetics and immunoblots analyses pertaining to inflammation, oxidative stress, cell survival, calcium signaling, and proliferation cascades.

RESULTS

Results distinctly revealed that pulsed 810 nm (10 Hz) PBM potentially influenced the cell survival and proliferation signaling pathway by significantly upregulated phospho-protein kinase B(phospho-Akt), phospho-extracellular-signal-regulated kinase 1 (ERK1), transient receptor potential vanilloid-3 (TRPV3), Ca²⁺ , calmodulin, transforming growth factor-β1 (TGF-β1), TGF-βR3, and Na ⁺ /K ⁺ -ATPase pump levels. PBM treatment resulted in reduction of exaggerated inflammatory responses evident by significantly repressed levels of interleukin-1β (IL-1β), IL-6, cyclooxygenase 2 (COX-2), and substance-P receptor (SPR), as well as inhibited apoptotic cell death by decreasing p53, cytochrome C, and caspase 3 levels (P < 0.05), which, in turn, effectively augment the wound repair in immunosuppressed rats. PBM treatment also lowered 4-hydroxynoneal (HNE) adduct level and NADP/NADPH ratio and upregulated the GRP78 expression, which might culminate into reduced oxidative stress and maintained the redox homeostasis.

CONCLUSIONS

Taken together, these findings would be helpful in better understanding of the molecular aspects involved in pulsed 810 nm laser-mediated dermal wound healing in immunosuppressed rats through regulation of cell survival and proliferation via Ca²⁺ -calmodulin, Akt, ERK, and redox signaling. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Role of photobiomodulation on the activation of the Smad pathway via TGF-β in wound healing

Wound healing is an essential process in which the separated or destroyed tissue attempts to restore itself into its normal state. In some instances, healing is prolonged and remains stagnant in the inflammatory phase, and is referred to as a chronic wound. At a cellular and molecular level, many factors are required during the process of successful wound healing, such as cytokines, polypeptide growth factors and components of the extracellular matrix (ECM). Transforming growth factor-beta (TGF-β) is considered as one of the essential growth factors in wound healing. Working through the Smad pathway, it is the main inducer of fibroblast differentiation which is essential for wound healing. Photobiomodulation (PBM) shows significant advantages in wound healing, and may stimulate cellular processes and tissue regeneration that results in an increase in growth factors and a decrease in inflammatory cytokines. Moreover, it leads to enhanced cell proliferation, migration, angiogenesis, and increased adenosine triphosphate (ATP) and cytochrome C oxidase (CCO) activity. In this review paper, we discuss the effects of PBM and its role on the activation of the TGF-β/Smad pathway in the process of wound healing.