Effect of low-level laser therapy on the modulation of the mitochondrial activity of macrophages

Low-level laser therapy, piezocision, or their combination vs. conventional treatment for orthodontic tooth movement : A hierarchical 6-arm split-mouth randomized clinical trial

PURPOSE

The use non-invasive or minimally invasive methods to accelerate orthodontic tooth movements (OTM) is desirable. In this regard, low-level laser therapy (LLLT, photobiomodulation) and piezocision are suggested. However, because the efficacies of these methods remain controversial/inconclusive, we investigated and compared these two methods.

METHODS

Sixty-four quadrants in 32 patients were randomized into three parallel intervention groups of 22, 22, and 20 (6 parallel arms, n = 64 treatment/control sides). Bilateral first premolars were extracted and canine retraction commenced. In each group, one side of the mouth was randomly selected as control, while the other side underwent each of three interventions: LLLT (940 nm, 8 J, 0.5 W, 16 s, 12 sites), piezocision, and "LLLT + piezocision". At the 3rd, 6th, and 9th follow-up weeks, canine retraction and anchorage loss were measured. Data were analyzed statistically (α = 0.05).

RESULTS

After 9 weeks, LLLT, piezocision, and LLLT + piezocision improved canine retraction by 0.51, 1.14, and 1.93 mm, respectively. LLLT accelerated canine retraction (compared to control) by 1.6-, 1.4-, and 1.2-fold in the 3rd, 6th, and 9th week, respectively. These statistics were 2.1-, 1.7-, and 1.5-fold for piezocision and 2.7-, 2.1-, and 1.8-fold for LLLT + piezocision. Compared to controls, each intervention showed significant retraction acceleration (p < 0.05). The effect of LLLT + piezocision was greater than that of isolated piezocision (p < 0.05), which itself was greater than that for isolated LLLT (p < 0.05).

CONCLUSION

All three methods accelerated OTM, with the combination of LLLT + piezocision producing the strongest and LLLT producing the weakest acceleration.

The Mechanisms and Efficacy of Photobiomodulation Therapy for Arthritis: A Comprehensive Review

Rheumatoid arthritis (RA) and osteoarthritis (OA) have a significant impact on the quality of life of patients around the world, causing significant pain and disability. Furthermore, the drugs used to treat these conditions frequently have side effects that add to the patient's burden. Photobiomodulation (PBM) has emerged as a promising treatment approach in recent years. PBM effectively reduces inflammation by utilizing near-infrared light emitted by lasers or LEDs. In contrast to photothermal effects, PBM causes a photobiological response in cells, which regulates their functional response to light and reduces inflammation. PBM's anti-inflammatory properties and beneficial effects in arthritis treatment have been reported in numerous studies, including animal experiments and clinical trials. PBM's effectiveness in arthritis treatment has been extensively researched in arthritis-specific cells. Despite the positive results of PBM treatment, questions about specific parameters such as wavelength, dose, power density, irradiation time, and treatment site remain. The goal of this comprehensive review is to systematically summarize the mechanisms of PBM in arthritis treatment, the development of animal arthritis models, and the anti-inflammatory and joint function recovery effects seen in these models. The review also goes over the evaluation methods used in clinical trials. Overall, this review provides valuable insights for researchers investigating PBM treatment for arthritis, providing important references for parameters, model techniques, and evaluation methods in future studies.

Effects of Photobiomodulation Therapy on Lung Function and Inflammatory Factors in Patients with COVID-19 During Acute Stage

Objective: We aimed to evaluate the effects of photobiomodulation therapy on the respiratory function and laboratory parameters in COVID-19 participants with respiratory involvement. Methods: A randomized, double-blind controlled design was used. This study was conducted at Koosar Hospital. Thirty participants with COVID-19 who were hospitalized met the inclusion criteria and were randomly assigned to two groups. Patients were treated with a program of five sessions of high-power photobiomodulation (intervention group) and placebo photobiomodulation (control group). Both groups received standard treatment. Outcomes were assessed before and after the intervention (two sessions), according to the immune system function and laboratory tests for the respiratory rate (RR), oxygen saturation, and inflammatory factors, including C-reactive protein (CRP), white blood cells, and interleukin-6 (IL-6), as well as complete blood count (CBC), hematocrit, hemoglobin, and ferritin. Results: Findings indicated that the values of ferritin, erythrocyte sedimentation ratio, CRP, IL-6, O2 saturation, and RR were significantly improved after the intervention in both groups (p < 0.05). Independent T-test analyses also indicated significant differences in the CRP, IL-6, and O2 saturation in the photobiomodulation group compared with the control group after the five-session intervention (p < 0.05). Conclusions: Application of photobiomodulation is recommended for treatment of respiratory problems in patients with COVID-19 to improve clinical signs and control inflammatory factors. Clinical Trial Registration: IRCT2017070934969N1.

Efficacy of Combined Photobiomodulation Therapy with Supplements versus Supplements alone in Restoring Thyroid Gland Homeostasis in Hashimoto Thyroiditis: A Clinical Feasibility Parallel Trial with 6-Months Follow-Up

Hashimoto thyroiditis (HT) is a thyroid-specific autoimmune disorder, triggering hypothyroidism in a population with an adequate dietary intake. Despite the current conventional treatment focuses on the permanent replacement of levothyroxine (LT4) deficiency, it appears that thyroid autoimmunity remains the cause of persistent symptoms in patients with HT, even when they achieve to be euthyroid from a biochemical standpoint. Photobiomodulation (PBM) showed to be an effective therapy in the management of autoimmune diseases, but with limited evidence. Hence, our study was conducted to appraise the efficacy of PBM therapy with supplements in restoring thyroid gland homeostasis in patients with HT compared with supplements alone. Seventy-four female subjects aged between 20 and 50 years old were recruited and divided equally into two groups: PBM and supplements group (group 1); and supplements alone group (group 2). The PBM dosimetry and treatment protocols were as follows: wavelength, 820 nm; power output, 200 mW; continuous emission mode; irradiating time, 20 s per point; fluence, 32 J/cm2 per point; treatment frequency, twice a week (excluding weekends); and treatment duration, three consecutive weeks. Whereas, the supplements protocol for both groups was the same, as follows: subjects with a serum level of vitamin D3 <40 ng/dL, who received replacement according to their serum levels, and all the subjects had a daily intake of 100 µg of oral selenium. The biochemical (FT3, FT4, antiTPO and antiTG) and anthropometric measurements were evaluated. Our findings showed significant improvement in group 1 parameters (PBM+ supplements) compared with group 2 (supplements only) in terms of weight loss and reduction in the following parameters: BMI, hip and waist circumference, waist/hip ratio, TSH, antiTPO, antiTG and treatment dose of LT4 (p < 0.05). Our results, for the first time, demonstrated an efficacy of PBM delivered at a lower fluence with supplements in restoring thyroid function, anthropometric parameters and lifestyle factors in patients with HT. Hence, extensive studies with a longer follow-up period are warranted.

The Effects and Mechanisms of PBM Therapy in Accelerating Orthodontic Tooth Movement

Malocclusion is one of the three major diseases, the incidence of which could reach 56% of the imperiled oral and systemic health in the world today. Orthodontics is still the primary method to solve the problem. However, it is clear that many orthodontic complications are associated with courses of long-term therapy. Photobiomodulation (PBM) therapy could be used as a popular way to shorten the course of orthodontic treatment by nearly 26% to 40%. In this review, the efficacy in cells and animals, mechanisms, relevant cytokines and signaling, clinical trials and applications, and the future developments of PBM therapy in orthodontics were evaluated to demonstrate its validity. Simultaneously, based on orthodontic mechanisms and present findings, the mechanisms of acceleration of orthodontic tooth movement (OTM) caused by PBM therapy were explored in relation to four aspects, including blood vessels, inflammatory response, collagen and fibers, and mineralized tissues. Also, the cooperative effects and clinical translation of PBM therapy in orthodontics have been explored in a growing numbers of studies. Up to now, PBM therapy has been gaining popularity for its non-invasive nature, easy operation, and painless procedures. However, the validity and exact mechanism of PBM therapy as an adjuvant treatment in orthodontics have not been fully elucidated. Therefore, this review summarizes the efficacy of PBM therapy on the acceleration of OTM comprehensively from various aspects and was designed to provide an evidence-based platform for the research and development of light-related orthodontic tooth movement acceleration devices.

Prospecting Local Treatments Used in Conjunction with Antivenom Administration Following Envenomation Caused by Animals: A Systematic Review

Envenomation caused by venomous animals may trigger significant local complications such as pain, edema, localized hemorrhage, and tissue necrosis, in addition to complications such as dermonecrosis, myonecrosis, and even amputations. This systematic review aims to evaluate scientific evidence on therapies used to target local effects caused by envenomation. The PubMed, MEDLINE, and LILACS databases were used to perform a literature search on the topic. The review was based on studies that cited procedures performed on local injuries following envenomation with the aim of being an adjuvant therapeutic strategy. The literature regarding local treatments used following envenomation reports the use of several alternative methods and/or therapies. The venomous animals found in the search were snakes (82.05%), insects (2.56%), spiders (2.56%), scorpions (2.56%), and others (jellyfish, centipede, sea urchin-10.26%). In regard to the treatments, the use of tourniquets, corticosteroids, antihistamines, and cryotherapy is questionable, as well as the use of plants and oils. Low-intensity lasers stand out as a possible therapeutic tool for these injuries. Local complications can progress to serious conditions and may result in physical disabilities and sequelae. This study compiled information on adjuvant therapeutic measures and underscores the importance of more robust scientific evidence for recommendations that act on local effects together with the antivenom.

The Novel Digital Therapeutics Sensor and Algorithm for Pressure Ulcer Care Based on Tissue Impedance

Visual diagnosis and rejuvenation are methods currently used to diagnose and treat pressure ulcers, respectively. However, the treatment process is difficult. We developed a biophotonic sensor to diagnose pressure ulcers and, subsequently, developed a pressure ulcer care device (PUCD.) We conducted animal and clinical trials to investigate the device's effectiveness. We confirmed the accuracy of the pressure ulcer diagnosis algorithm to be 91% and we observed an 85% reduction in immune cells when using the PUCD to treat pressure ulcer-induced mice. Additionally, we compared the treatment group to the pressure ulcer induction group to assess the PUCD's effectiveness in identifying immune cells through its nuclear shape. These results indicate a positive effect and suggest the use of PUCD as a recovery method for pressure ulcer diagnosis and treatment.

Low-power laser in increasing doses improve wound healing process in rats

Low-power laser has been studied and applied as an auxiliary tool in wound healing. However, as it is a therapy with several variables to be controlled, there is great difficulty in establishing protocols and comparing its efficacy. Therefore, the objective of this study was to evaluate the effects of the use of low-power laser in fixed and crescent doses in the healing of skin wounds in rats. Seventy-five male Wistar rats were divided into three groups: G1 with animals that did not receive laser radiation; G2 with animals treated with fixed dose of 3 J/cm2 laser; G3 with animals treated with laser in increasing doses of 1 J/cm2, 3 J/cm2, 5 J/cm2. Macroscopic and histological analysis were performed. The lowest intensity of PMN was observed in the irradiated groups and G3 had lower intensity of this infiltrate compared to G1 and G2 (p <0.05). On the seventh day of injury, PMN infiltrate decreased in all groups, especially in G3 (p<0.05). It was observed that G2 had more blood vessels than G1 and G3 after 7 days of wound creation (p ˂ 0.05). Collagen quantification showed that laser-treated groups have increased collagen deposition. Different responses in the wound healing process were observed comparing G2 and G3 groups. The fluence of 1J/cm2 presented better results in the anti-inflammatory action than 3 J/cm2, although G3 presented the greatest amount of total collagen after ten days of treatment.

Effects of different protocols of defocused high-power laser on the viability and migration of myoblasts-a comparative in vitro study

The aim of the present study was to analyze for the first time the effect of photobiomodulation therapy (PBMT) using defocused high-power laser (DHPL) in myoblast cell line C2C12 viability and migration and compare them with low-power laser therapy. Cells were divided into 9 groups: Sham irradiation 10% fetal bovine serum (FBS); Sham irradiation 5%FBS; low-power laser 0.1 W; DHPL 810 1 W; DHPL 810 2 W; DHPL 980 1 W; DHPL 980 2 W; DHPL dual 1 W; DHPL dual 2 W. To simulate stress conditions, all groups exposed to irradiation were maintained in DMEM 5% FBS. The impact of therapies on cell viability was assessed through sulforhodamine B assay and on cells migration through scratch assays and time-lapse. Myoblast viability was not modified by PBMT protocols. All PBMT protocols were able to accelerate the scratch closure after 6 and 18 h of the first irradiation (p < 0.001). Also, an increase in migration speed, with a more pronounced effect of DHPL laser using dual-wavelength protocol with 2 W was observed (p < 0.001). In conclusion, the diverse PBMT protocols used in this study accelerated the C2C12 myoblasts migration, with 2-W dual-wavelength outstanding as the most effective protocol tested. Benefits from treating muscle injuries with PBMT appear to be related to its capacity to induce cell migration without notable impact on cell viability.

Near-infrared light reduces β-amyloid-stimulated microglial toxicity and enhances survival of neurons: mechanisms of light therapy for Alzheimer's disease

BACKGROUND

Low-intensity light can decelerate neurodegenerative disease progression and reduce amyloid β (Aβ) levels in the cortex, though the cellular and molecular mechanisms by which photobiomodulation (PBM) protects against neurodegeneration are still in the early stages. Microglia cells play a key role in the pathology of Alzheimer's disease by causing chronic inflammation. We present new results concerning the PBM of both oxidative stress and microglia metabolism associated with the activation of metabolic processes by 808 nm near-infrared light.

METHODS

The studies were carried out using healthy male mice to obtain the microglial cell suspension from the hippocampus. Oligomeric β-amyloid (1-42) was prepared and used to treat microglia cells. Light irradiation of cells was performed using diode lasers emitting at 808 nm (30 mW/cm² for 5 min, resulting in a dose of 10 J/cm²). Mitochondrial membrane potential, ROS level studies, cell viability, apoptosis, and necrosis assays were performed using epifluorescence microscopy. Phagocytosis, nitric oxide and H₂O₂ production, arginase, and glucose 6-phosphate dehydrogenase activities were measured using standard assays. Cytokines, glucose, lactate, and ATP were measurements with ELISA. As our data were normally distributed, two-way ANOVA test was used.

RESULTS

The light induces a metabolic shift from glycolysis to mitochondrial activity in pro-inflammatory microglia affected by oligomeric Aβ. Thereby, the level of anti-inflammatory microglia increases. This process is accompanied by a decrease in pro-inflammatory cytokines and an activation of phagocytosis. Light exposure decreases the Aβ-induced activity of glucose-6-phosphate dehydrogenase, an enzyme that regulates the rate of the pentose phosphate pathway, which activates nicotinamide adenine dinucleotide phosphate oxidases to further produce ROS. During co-cultivation of neurons with microglia, light prevents the death of neurons, which is caused by ROS produced by Aβ-altered microglia.

CONCLUSIONS

These original data clarify reasons for how PBM protects against neurodegeneration and support the use of light for therapeutic research in the treatment of Alzheimer's disease.

Macrophages Modulated by Red/NIR Light: Phagocytosis, Cytokines, Mitochondrial Activity, Ca2+ Influx, Membrane Depolarization and Viability

Low-level light therapy (LLLT) is emerging as a promising therapeutic approach to modulate the biochemical and molecular processes within living cells. LLLT is known to produce local and systemic effects; therefore, immune cells in local tissues or in the circulation are affected by light. However, this specific effect remains weakly explored. In this study, the effect of red (650 nm) and NIR (808 nm) light on phagocytosis (respiratory burst), cytokine expression, mitochondrial activity, ROS generation, Ca²⁺ influx and membrane depolarization in macrophages in vitro is investigated. Both the phagocytic capacity and adhesion of macrophages strongly (˜2.5 times) increased in the first hours after exposure to light in a dose-dependent manner. The light-evoked upregulation of phagocytosis is found to be less efficient than the maximal pharmacologically induced enhancement of ˜3.2 times. Also, red/NIR light reduces the production of pro-inflammatory cytokines and activates the secretion of anti-inflammatory cytokines by several times in activated macrophages. At the same time, the viability shows a biphasic dose response: it increases after irradiation with lower doses (0.3-1 J cm^-2 ) and decreases after treatment with higher doses (18-30 J cm^-2 ), which is apparently associated with the upregulation of ROS generation, followed by an increase in the mitochondrial activity.

Effect of photobiomodulation on mitochondrial dynamics in peripheral nervous system in streptozotocin-induced type 1 diabetes in rats

There is no effective treatment to halt peripheral nervous system damage in diabetic peripheral neuropathy. Mitochondria have been at the center of discussions as important factors in the development of neuropathy in diabetes. Photobiomodulation has been gaining clinical acceptance as it shows beneficial effects on a variety of nervous system disorders. In this study, the effects of photobiomodulation (904 nm, 45 mW, 6.23 J/cm², 0.13 cm², 60 ns pulsed time) on mitochondrial dynamics were evaluated in an adult male rat experimental model of streptozotocin-induced type 1 diabetes. Results presented here indicate that photobiomodulation could have an important role in preventing or reversing mitochondrial dynamics dysfunction in the course of peripheral nervous system damage in diabetic peripheral neuropathy. Photobiomodulation showed its effects on modulating the protein expression of mitofusin 2 and dynamin-related protein 1 in the sciatic nerve and in the dorsal root ganglia neurons of streptozotocin-induced type 1 diabetes in rats.

Altered VDAC-HK association and apoptosis in mouse peripheral blood lymphocytes exposed to diabetic condition: an in vitro and in vivo study

Increased apoptotic lymphocytes have been correlated to a high incidence of infection in poorly controlled diabetes. This study aimed to determine whether altered voltage-dependent anion channel (VDAC)-hexokinase (HK) association contributes to the increase in apoptosis. Mouse peripheral blood lymphocytes (PBL) exposed to high glucose (Glc)/palmitic acid (PA) were used as the in vitro model, which was compared with PBL isolated from alloxan-induced diabetic mice (in vivo model). Our results showed a significant increase in apoptosis as indicated by the apoptotic index, caspase-3 activity, mitochondrial membrane potential and ultrastructural study. HK and glucose-6-phosphate dehydrogenase (G6PDH) activities were markedly reduced with a profound increase in glucose-6-phosphate level. Co-immunoprecipitation confirms HK interaction with VDAC, an outer mitochondrial membrane protein. Inhibited glycolytic enzyme, i.e. HK and reduced HK-VDAC interaction in our study could contribute to increased apoptosis in lymphocytes exposed to high Glc/PA. Targeting HK-VDAC interaction may therefore provide therapeutic potential for the treatment of diabetes-associated infection.

Participation of the Immune System and Hedgehog Signaling in Neoangiogenesis Under Laser Photobiomodulation

Introduction: This study aimed to characterize immune and endothelial cells, myofibroblasts and pericytes, and positive cells for hedgehog proteins in late tissue repair of rats skin wounds treated with 670 nm photobiomodulation therapy (PBMT). Methods: A blind experimental study was conducted, in order to assess the effect of PBMT in later stages of healing, with emphasis on neoangiogenesis, immune cells and Hedgehog signaling. Forty Wistar rats were allocated randomly in two groups; control and treated with a diode GaAlAs laser (9 mW, 670 nm, 0.031 W/cm², spot size of 0.28 cm², fluence of 4 J/ cm² applied every other day, until a total dose of 16 J/cm² was achieved). Standardized skin wounds were performed and the animals were euthanized at 14, 21, 28 and 35 days. Tissue sections were subjected to hematoxylin-eosin and immunohistochemistry for CD31, NG2, smooth muscle alpha actin, CD8, CD68, Ptch, Gli-2 and Ihh. All histomorphometric data were statistically analyzed and significance level was at P<0.05. Results: At late stages of wound healing, neoangiogenesis persisted as revealed for the number of CD31+ cells (P = 0.016) and NG2+ and smooth muscle alpha actin positive pericytes (P = 0.025), for both experimental groups. By day 21, laser-treated group had decreased CD68+ cells (P = 0.032) and increased CD8+ (P = 0.038). At remodeling stage, there were positive cells for the hedgehog signaling pathway family which seemed to be activated. Conclusion: These data suggest that photobiomodulation therapy was able to modulate extracellular matrix remodelling even at the later stages of wound healing.

Review of light parameters and photobiomodulation efficacy: dive into complexity

Photobiomodulation (PBM) therapy, previously known as low-level laser therapy, was discovered more than 50 years ago, yet there is still no agreement on the parameters and protocols for its clinical application. Some groups have recommended the use of a power density less than 100  mW/cm2 and an energy density of 4 to 10  J/cm2 at the level of the target tissue. Others recommend as much as 50  J/cm2 at the tissue surface. The wide range of parameters that can be applied (wavelength, energy, fluence, power, irradiance, pulse mode, treatment duration, and repetition) in some cases has led to contradictory results. In our review, we attempt to evaluate the range of effective and ineffective parameters in PBM. Studies in vitro with cultured cells or in vivo with different tissues were divided into those with higher numbers of mitochondria (muscle, brain, heart, nerve) or lower numbers of mitochondria (skin, tendon, cartilage). Graphs were plotted of energy density against power density. Although the results showed a high degree of variability, cells/tissues with high numbers of mitochondria tended to respond to lower doses of light than those with lower number of mitochondria. Ineffective studies in cells with high mitochondrial activity appeared to be more often due to over-dosing than to under-dosing.

A Comparison of the Rate of Retraction with Low-level Laser Therapy and Conventional Retraction Technique

Background and Objectives:

A major concern of orthodontic patients is treatment time. Reducing the treatment time requires increasing the rate of orthodontic tooth movement. Research has proved that bone resorption is the rate-limiting step in tooth movement. Therefore, any procedure that potentiates osteoclastic activity is capable of increasing the rate of orthodontic tooth movement. Low-level laser has been indicated to have the capability to facilitate the differentiation of the osteoclastic and osteoblastic cells, which are responsible for the bone remodeling process. The purpose of this study was to evaluate whether the low-level laser therapy can accelerate orthodontic tooth movement during en masse retraction.

Method:

The study was a split-mouth design. The experimental side was exposed to biostimulation using 810 nm gallium-aluminium-arsenide diode laser. A total of 10 irradiations for 10 s per site were given 5 on the buccal side and 5 on the palatal side of the tooth. The total energy density at each application was 10 J with an interappointment gap of 3 weeks. The retraction was carried using a constant force of 150 gm. A digital vernier caliper measurement was used to measure the distance between the contact points of the maxillary canine and second premolar on 1^st and 84^th day.

Results:

The rate of orthodontic tooth movement was faster on the experimental side, and the difference between the two sides was statistically significant (P < 0.014).

Interpretation and Conclusion:

It was concluded that biostimulation carried out using an 810 nm diode laser is capable of increasing the rate of extraction space closure. Hence, it is capable of increasing the rate of orthodontic tooth movement.

Mitochondrial dysfunction, perturbations of mitochondrial dynamics and biogenesis involved in endothelial injury induced by silica nanoparticles

As silica nanoparticles (SiNPs) pervade the global economy, however, the followed emissions during the manufacturing, use, and disposal stages inevitably bring an environmental release, potentially result in harmful impacts. Endothelial dysfunction precedes cardiovascular disease, and is often accompanied by mitochondrial impairment and dysfunction. We had reported endothelial dysfunction induced by SiNPs, however, the related mechanisms by which SiNPs interact with mitochondria are not well understood. In the present study, we examined SiNPs-induced mitochondrial dysfunction, and further demonstrated their adverse effects on mitochondrial dynamics and biogenesis in endothelial cells (HUVECs). Consequently, SiNPs entered mitochondria, caused mitochondrial swelling, cristae disruption and even disappearance. Further analyses revealed SiNPs increased the intracellular level of mitochondrial reactive oxygen species, eventually resulting in the collapse of mitochondrial membrane potential, impairments in ATP synthesis, cellular respiration and the activities of three ATP-dependent enzymes (including Na⁺/K⁺-ATPase, Ca²⁺-ATPase and Ca²⁺/Mg²⁺-ATPase), as well as an elevated intracellular calcium level. Furthermore, mitochondria in SiNPs-treated HUVECs displayed a fission phenotype. Accordingly, dysregulation of the key gene expressions (FIS1, DRP1, OPA1, Mfn1 and Mfn2) involved in fission/fusion event further certified the SiNPs-induced perturbation of mitochondrial dynamics. Meanwhile, SiNPs-treated HUVECs displayed declined levels of mitochondrial DNA copy number, PGC-1α, NRF1 and also TFAM, indicating an inhibition of mitochondrial biogenesis triggered by SiNPs via PGC-1α-NRF1-TFAM signaling. Overall, SiNPs triggered endothelial toxicity through mitochondria as target, including the induction of mitochondrial dysfunction, as well as the perturbations of their dynamics and biogenesis.

Synergistic effects of Combined Therapy: nonfocused ultrasound plus Aussie current for noninvasive body contouring

BACKGROUND AND OBJECTIVES

Nowadays, there are several noninvasive technologies being used for improving of body contouring. The objectives of this pilot study were to verify the effectiveness of the Heccus® device, emphasizing the synergism between nonfocused ultrasound plus Aussie current in the improvement of body contour, and to determine if the association of this therapy with whole-body vibration exercises can have additional positive effects in the results of the treatments.

SUBJECTS AND METHODS

Twenty healthy women aged 20-40 years participated in the study. Ten patients received Combined Therapy treatment (G1) and the other 10 participants received Combined Therapy with additional vibratory platform treatment (G2). Anthropometric and standardized photography analysis, ultrasonography, cutometry and self-adminestered questionnaires of tolerance and satisfaction levels with the treatment were used.

RESULTS

Compared with baseline values, reduction of fat thickness was observed by ultrasonography in the posterior thigh area in the G1 group (P<0.05) and in the buttocks (P<0.05) and the posterior thigh areas (P<0.05) in the G2. All the treated areas in both groups showed reduction in cellulite degree in the buttocks, G1 (P<0.05) and G2 (P<0.05), and in posterior thigh areas, G1 (P<0.05) and G2 (P<0.05). Optimal improvement of skin firmness (G1, P<0.0001; G2, P=0.0034) in the treated areas was observed in both groups.

CONCLUSION

We conclude that the synergistic effects of the Combined Therapy (nonfocused ultrasound plus Aussie current) might be a good option with noninvasive body contouring treatment for improving the aspect of the cellulite, skin firmness and localized fat. If used in association with the whole-body vibratory platform, the results can be better, especially in the treatment of localized fat. Further studies with larger sample size should be performed to confirm these results.

A Comparative Evaluation of Interleukin 1 Beta and Prostaglandin E2 with and without Low-level Laser Therapy during En masse Retraction

Background and Objectives:

Orthodontic forces are known to produce mechanical damage and inflammatory mediators such as prostaglandins (PGs) and interleukin (IL)-1, in the periodontium and dental pulp. Low-level laser therapy (LLLT) is a stimulator of the on-going biological process in tissue and found to be effective in modulating cell activity, which is involved in orthodontic tooth movement. Here, a humble effort has been made to study two such cytokines, namely IL-1 β and PG E2 (PGE2) which are partially responsible for bone turnover. The purpose of this study was to compare the changes occurring in the values of IL-1 β and PGE2 in the gingival crevicular fluid (GCF) during en masse retraction with and without LLLT.

Methodology:

GCF was collected using micropipettes from the distal ends of upper canines. The experimental side was exposed to biostimulation using 810 nm gallium-aluminum-arsenide diode laser and the contralateral side taken as control. A total of 10 irradiations for 10 s per site were given, five on the buccal side and five on the palatal side, to cover the entire periodontal fibers and the alveolar process around the tooth. After 7 days and 21 days of retraction, GCF sample was collected. Quantitative analysis of IL-1 β and PGE2 in the GCF samples was assessed using a commercially available Raybiotech® IL-1 β and Human PGE2.

Results:

(1) IL-1 β and PGE2 levels showed significant results from baseline to 21 days after LLLT irradiation. (2) LLLT-assisted retraction was significantly faster than conventional retraction.

Interpretation and Conclusion:

It was concluded from the study that IL-1 β and PGE2 levels peaked after LLLT. The difference in the levels of both cytokines was statistically significant.

What Can be Learned from the Time Course of Changes in Low-Frequency Stimulated Muscle?

Not available.

Effect of Laser Photobiomodulation with Gradual or Constant Doses in the Regeneration of Rats' Mental Nerve After Lesion by Compression

OBJECTIVE

Assess morphologically the efficacy of constant dose (CD) or gradual dose (GD) in photobiomodulation therapy (PBMT) during the regeneration process of rats' mental nerve after compression lesion.

MATERIALS AND METHODS

Forty-eight male Wistar rats were used and divided into four groups (n = 12): negative control (NC): lesion by compression; positive control (PC): no lesion; GD: lesion by compression and PBMT with GD; and CD: lesion by compression and PBMT with CD. One day after the surgery, the groups GD and CD underwent PBMT daily in three equidistant points around the incision area. The parameters were wavelength of 808 nm, 100 mW, CD received treatment with 120 J/cm², while GD underwent the protocol of application: 1st and 4th sessions: 80 J/cm²; 5th to 8th sessions: 90 J/cm²; 9th to 12th sessions: 100 J/cm²; 13th to 16th sessions: 110 J/cm²; and 17th to 20th sessions: 120 J/cm². Euthanasias were performed at 3, 7, 14, and 21 days. Qualitative and quantitative analysis of the mental nerves were performed with ANOVA (analysis of variance) and Tukey tests (p ≤ 0.05).

RESULTS

It was observed that PBMT was able to accelerate the process of nerve regeneration presenting an increase in the number of myelinated fibers starting at 14 days of treatment for groups CD and GD, and at 21 days they were similar to PC. It was observed a better lamellar organization of myelin sheath at 7 days for GD and at 14 days for CD, similar to PC. Both GD and CD presented significant differences compared to NC and PC for thickness of the myelin sheath, outer perimeter, internal area, and number of myelin fibers.

CONCLUSIONS

PBMT presented positive effect on the regeneration of nerve starting at 14 days, and after 21 days there was no difference between GD and CD.

Low-level laser therapy for beta amyloid toxicity in rat hippocampus

Beta amyloid (Aβ) is well accepted to play a central role in the pathogenesis of Alzheimer's disease (AD). The present work evaluated the therapeutic effects of low-level laser irradiation (LLI) on Aβ-induced neurotoxicity in rat hippocampus. Aβ 1-42 was injected bilaterally to the hippocampus CA1 region of adult male rats, and 2-minute daily LLI treatment was applied transcranially after Aβ injection for 5 consecutive days. LLI treatment suppressed Aβ-induced hippocampal neurodegeneration and long-term spatial and recognition memory impairments. Molecular studies revealed that LLI treatment: (1) restored mitochondrial dynamics, by altering fission and fusion protein levels thereby suppressing Aβ-induced extensive fragmentation; (2) suppressed Aβ-induced collapse of mitochondrial membrane potential; (3) reduced oxidized mitochondrial DNA and excessive mitophagy; (4) facilitated mitochondrial homeostasis via modulation of the Bcl-2-associated X protein/B-cell lymphoma 2 ratio and of mitochondrial antioxidant expression; (5) promoted cytochrome c oxidase activity and adenosine triphosphate synthesis; (6) suppressed Aβ-induced glucose-6-phosphate dehydrogenase and nicotinamide adenine dinucleotide phosphate oxidase activity; (7) enhanced the total antioxidant capacity of hippocampal CA1 neurons, whereas reduced the oxidative damage; and (8) suppressed Aβ-induced reactive gliosis, inflammation, and tau hyperphosphorylation. Although development of AD treatments has focused on reducing cerebral Aβ levels, by the time the clinical diagnosis of AD or mild cognitive impairment is made, the brain is likely to have already been exposed to years of elevated Aβ levels with dire consequences for multiple cellular pathways. By alleviating a broad spectrum of Aβ-induced pathology that includes mitochondrial dysfunction, oxidative stress, neuroinflammation, neuronal apoptosis, and tau pathology, LLI could represent a new promising therapeutic strategy for AD.

Low-Level Laser Irradiation Improves Depression-Like Behaviors in Mice

Major depressive disorder (MDD) is one of the leading forms of psychiatric disorders, characterized by aversion to mobility, neurotransmitter deficiency, and energy metabolic decline. Low-level laser therapy (LLLT) has been investigated in a variety of neurodegenerative disorders associated with mitochondrial dysfunction and functional impairments. The goal of this study was to examine the effect of LLLT on depression-like behaviors and to explore the potential mechanism by detecting mitochondrial function following LLLT. Depression models in space restriction mice and Abelson helper integration site-1 (Ahi1) knockout (KO) mice were employed in this work. Our results revealed that LLLT effectively improved depression-like behaviors, in the two depression mice models, by decreasing immobility duration in behavioral despair tests. In addition, ATP biosynthesis and the level of mitochondrial complex IV expression and activity were significantly elevated in prefrontal cortex (PFC) following LLLT. Intriguingly, LLLT has no effects on ATP content and mitochondrial complex I-IV levels in other tested brain regions, hippocampus and hypothalamus. As a whole, these findings shed light on a novel strategy of transcranial LLLT on depression improvement by ameliorating neurotransmitter abnormalities and promoting mitochondrial function in PFC. The present work provides concrete groundwork for further investigation of LLLT for depression treatment.

An in vitro method to test the safety and efficacy of low-level laser therapy (LLLT) in the healing of a canine skin model

Background

Low-level laser therapy (LLLT) has been used clinically as a treatment modality for a variety of medical conditions including wound-healing processes. It is an attractive and emerging method to enhance wound healing and improve clinical outcomes both in human and veterinary medicine. Despite the fact that the use of LLLT continues to gain in popularity, there is no universally accepted theory that defends all its cellular effects and beneficial biological processes in tissue repair. The present study was designed to evaluate the effect of LLLT on cellular migration and proliferation of cultured canine epidermal keratinocytes (CPEK) in an in vitro wound healing model.

Results

Keratinocyte migration and proliferation were assessed using a scratch migration assay and a proliferation assay, respectively. Fifteen independent replicates were performed for each assay. Canine epidermal keratinocyte cells exposed to LLLT with 0.1, 0.2, and 1.2 J/cm² migrated significantly more rapidly (p < 0.03) and showed significantly higher rates of proliferation (p < 0.0001) compared to non-irradiated cells cultured in the same medium and cells exposed to the higher energy dose of 10 J/cm². Irradiation with 10 J/cm² was characterized by decreased cellular migration and proliferation. These results revealed that LLLT has a measurable, dose-dependent effect on two different aspects of keratinocyte biology in vitro.

Conclusion

In this in vitro wound-healing model, LLLT increased cellular migration and proliferation at doses of 0.1, 0.2, and 1.2 J/cm² while exposure to 10 J/cm² decreased cellular migration and proliferation. These data suggest that the beneficial effects of LLLT in vivo may be due, in part, to effects on keratinocyte behavior.

Cell viability, reactive oxygen species, apoptosis, and necrosis in myoblast cultures exposed to low-level infrared laser

Low-level infrared laser is considered safe and effective for treatment of muscle injuries. However, the mechanism involved on beneficial effects of laser therapy are not understood. The aim was to evaluate cell viability, reactive oxygen species, apoptosis, and necrosis in myoblast cultures exposed to low-level infrared laser at therapeutic fluences. C2C12 myoblast cultures at different (2 and 10 %) fetal bovine serum (FBS) concentrations were exposed to low-level infrared laser (808 nm, 100 mW) at different fluences (10, 35, and 70 J/cm(2)) and evaluated after 24, 48, and 72 h. Cell viability was evaluated by WST-1 assay; reactive oxygen species (ROS), apoptosis, and necrosis were evaluated by flow cytometry. Cell viability was decreased atthe lowest FBS concentration. Laser exposure increased the cell viability in myoblast cultures at 2 % FBS after 48 and 72 h, but no significant increase in ROS was observed. Apoptosis was decreased at the higher fluence and necrosis was increased at lower fluence in myoblast cultures after 24 h of laser exposure at 2 % FBS. No laser-induced alterations were obtained at 10 % FBS. Results show that level of reactive oxygen species is not altered, at least to those evaluated in this study, but low-level infrared laser exposure affects cell viability, apoptosis, and necrosis in myoblast cultures depending on laser fluence and physiologic conditions of cells.