Effects Of Photobiomodulation Research Articles

Directed physiological networks in the human prefrontal cortex at rest and post transcranial photobiomodulation

Cerebral infra-slow oscillation (ISO) is a source of vasomotion in endogenic (E; 0.005–0.02 Hz), neurogenic (N; 0.02–0.04 Hz), and myogenic (M; 0.04–0.2 Hz) frequency bands. In this study, we quantified changes in prefrontal concentrations of oxygenated hemoglobin (Δ[HbO]) and redox-state cytochrome c oxidase (Δ[CCO]) as hemodynamic and metabolic activity metrics, and electroencephalogram (EEG) powers as electrophysiological activity, using concurrent measurements of 2-channel broadband near-infrared spectroscopy and EEG on the forehead of 22 healthy participants at rest. After preprocessing, the multi-modality signals were analyzed using generalized partial directed coherence to construct unilateral neurophysiological networks among the three neurophysiological metrics (with simplified symbols of HbO, CCO, and EEG) in each E/N/M frequency band. The links in these networks represent neurovascular, neurometabolic, and metabolicvascular coupling (NVC, NMC, and MVC). The results illustrate that the demand for oxygen by neuronal activity and metabolism (EEG and CCO) drives the hemodynamic supply (HbO) in all E/N/M bands in the resting prefrontal cortex. Furthermore, to investigate the effect of transcranial photobiomodulation (tPBM), we performed a sham-controlled study by delivering an 800-nm laser beam to the left and right prefrontal cortex of the same participants. After performing the same data processing and statistical analysis, we obtained novel and important findings: tPBM delivered on either side of the prefrontal cortex triggered the alteration or reversal of directed network couplings among the three neurophysiological entities (i.e., HbO, CCO, and EEG frequency-specific powers) in the physiological network in the E and N bands, demonstrating that during the post-tPBM period, both metabolism and hemodynamic supply drive electrophysiological activity in directed network coupling of the prefrontal cortex (PFC). Overall, this study revealed that tPBM facilitates significant modulation of the directionality of neurophysiological networks in electrophysiological, metabolic, and hemodynamic activities.

Effects of slit lamp-delivered retinal laser photobiomodulation in a rat model of choroidal neovascularization.

Neovascular age-related macular degeneration, also known as exudative or wet age-related macular degeneration, is the leading cause of blindness in the developed world. Photobiomodulation has the potential to target the up-stream hypoxic and pro-inflammatory drivers of choroidal neovascularization. This study investigated whether photobiomodulation attenuates characteristic pathological features of choroidal neovascularization in a rodent model. Experimental choroidal neovascularization was induced in Brown Norway rats with laser photocoagulation. A custom-designed, slit-lamp-mounted, 670 nm laser was used to administer retinal photobiomodulation every 3 days, beginning 6 days prior to choroidal neovascularization induction and continuing until the animals were killed 14 days later. The effect of photobiomodulation on the size of choroidal neovascular membranes was determined using isolectin-B4 immunohistochemistry and spectral domain-optical coherence tomography. Vascular leakage was determined with fluorescein angiography. The effect of treatment on levels of vascular endothelial growth factor expression was quantified with enzyme-linked immunosorbent assay. Treatment with photobiomodulation was associated with choroidal neovascular membranes that were smaller, had less fluorescein leakage, and a diminished presence of inflammatory cells as compared to sham eyes. These effects were not associated with a statistically significant difference in the level of vascular endothelial growth factor when compared to sham eyes. The data shown herein indicate that photobiomodulation attenuates pathological features of choroidal neovascularization in a rodent model by mechanisms that may be independent of vascular endothelial growth factor.

Enhancing nerve regeneration in infraorbital nerve injury rat model: effects of vitamin B complex and photobiomodulation.

Orofacial nerve injuries may result in temporary or long-term loss of sensory function and decreased quality of life in patients. B vitamins are required for DNA synthesis and the repair and maintenance of phospholipids. In particular, vitamins B1, B6, and B12 are essential for neuronal function. Deficiency in vitamin B complex (VBC) has been linked to increased oxidative stress, inflammation and demyelination. Photobiomodulation (PBM) has antioxidant activity and is neuroprotective. In addition, a growing literature attests to the positive effects of PBM on nerve repair. To assess the effect of PBM and VBC on regenerative process we evaluated the expression of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), myelin basic protein (MBP), laminin and neurofilaments (NFs) using Western blotting to identify regenerative pattern after chronic constriction injury of the infraorbital nerve (CCI IoN) treated by PBM, VBC or its combination. After CCI IoN, the rats were divided into six groups naive, sham, injured (CCI IoN), treated with photobiomodulation (904nm, 6.23J/cm2, CCI IoN + PBM), treated with VBC (containing B1, B6 and B12) 5 times, CCI IoN + VBC) and treated with PBM and VBC (CCI IoN + VBC + PBM). The treatments could revert low expression of BDNF, MBP and laminin. Also reverted the higher expression of neurofilaments and enhanced expression of NGF. PBM and VBC could accelerate injured infraorbital nerve repair in rats through reducing the expression of neurofilaments, increasing the expression of BDNF, laminin and MBP and overexpressing NGF. These data support the notion that the use of PBM and VBC may help in the treatment of nerve injuries. This finding has potential clinical applications.

The effects of photobiomodulation on the improvement of sperm parameters: A review study.

The prevalence of male infertility has become a significant clinical concern worldwide, with a noticeable upward trend in recent times. The rates of fertilization and subsequent development of embryos are dependent on many parameters associated with the quality and viability of sperm. Photobiomodulation (PBM) is a promising approach with a great potential for translational applications in the treatment of spermatozoa exhibiting low quality and motility. In this study, a comprehensive analysis of the existing literature, specifically examining the mechanisms of action of PBM has been presented. Our objective was to enhance knowledge in the field of laser light therapy in order to promote the usage of irradiation in clinical settings in a more effective way. Within the realm of reproductive science, the utilization of PBM has been employed to enhance the metabolic processes, motility, and viability of spermatozoa. This is attributed to its advantageous effects on mitochondria, resulting in the activation of the mitochondrial respiratory chain and subsequent synthesis of ATP. This therapeutic approach can be highly advantageous in circumventing the reliance on chemical substances within the culture medium for spermatozoa while also facilitating the viability and motility of spermatozoa, particularly in circumstances involving thawing or samples with significant immotility.

Comparative Evaluation of the Effect of Photobiomodulation on Pain Reduction in Individuals Undergoing Segmental Retraction Using a Closing Loop: A Randomized Controlled Clinical Trial

Comparative Evaluation of the Effect of Photobiomodulation on Pain Reduction in Individuals Undergoing Segmental Retraction Using a Closing Loop: A Randomized Controlled Clinical Trial

Evaluation of Photobiomodulation on myocardial function of Patients with Advanced Ischemic Cardiomyopathy, A Case Series

BackgroundHeart failure is a growing cardiovascular disease burden with high mortality rates, primarily attributed to myocardial ischemia. Previous studies have shown promising effects of Photobiomodulation in heart failure treatment. In this study, we aimed to investigate the effect of Photobiomodulation on myocardial function of patients with advanced ischemic heart failure. MethodA non-randomized case series study involving 10 advanced heart failure patients was conducted. Patients received 15 sessions of transcutaneous and intravenous Photobiomodulation therapy using low-level red (658 nm) and infrared lasers (810 nm). All participants were evaluated by six-minute walk tests, dyspnea function classes, and echocardiography. 3 months after the sessions, the mentioned tests were reevaluated ResultThe study included ten cardiomyopathic patients, 90% male and the mean age was 63.20±6.01 years. The six-minute walk test change and shortness of breath function class change has 0.852 (p-value=0.006) correlation and the correlation between the Six-minute walk test change and the Systolic ejection fraction rate change, was 0.73 (p-value=0.025). ConclusionBased on the results of the study, it can be concluded that interventions in cardiomyopathic patients have shown promising improvements in certain cardiac function parameters. Specifically, the significant enhancement in the six-minute walk test post-intervention (p=0.013) suggests a positive impact on functional capacity. Although the increase in systolic ejection fraction rate was not statistically significant (p=0.197), the correlations identified provide valuable insights into the interplay between variables such as shortness of breath function class and the six-minute walk test. These findings underscore the complexity of managing cardiomyopathy and highlight the importance of further research to elucidate the relationships between different clinical parameters and patient outcomes in this population.

Disentangling the effects of near-infrared light stimulation and exercise on cognitive function in fNIRS studies

Functional near-infrared spectroscopy (fNIRS) studies often aim to measure changes in the brain's hemodynamic response in relation to a specific intervention. We recently showed how a fNIRS device could induce photobiomodulatory effects on cognition by using its near-infrared (NIR) light. However, so far, fNIRS research has overlooked the stimulatory potential intrinsic to this technique. The work by Kuwamizu et al. (2023) on pupil dynamics during exercise is no exception. Here, we suggest a fix to their experimental design, which could be taken into account in other fNIRS studies, to guarantee an adequate level of control for possible unconsidered photobiomodulatory effects.

Photobiomodulation inhibits neuronal firing in the superficial but not deep layer of a rat spinal dorsal horn

Photobiomodulation (PBM) has attracted attention as a treatment for chronic pain. Previous studies have reported that PBM of the sciatic nerve inhibits neuronal firing in the superficial layers (lamina I–II) of the spinal dorsal horn of rats, which is evoked by mechanical stimulation that corresponds to noxious stimuli. However, the effects of PBM on the deep layers (lamina III–IV) of the spinal dorsal horn, which receive inputs from innocuous stimuli, remain poorly understood. In this study, we examined the effect of PBM of the sciatic nerve on firing in the deep layers of the spinal dorsal horn evoked by mechanical stimulation. Before and after PBM, mechanical stimulation was administered to the cutaneous receptive field using 0.6–26.0 g von Frey filaments (vFFs), and vFF-evoked firing in the deep layers of the spinal dorsal horn was recorded. The vFF-evoked firing frequencies were not altered after the PBM for any of the vFFs. The inhibition rate for 26.0 g vFF-evoked firing was approximately 13 % in the deep layers and 70 % in the superficial layers. This suggests that PBM selectively inhibits the transmission of pain information without affecting the sense of touch. PBM has the potential to alleviate pain while preserving the sense of touch.

Evaluation of photobiomodulation in the salivary production of patients with hyposalivation induced by antihypertensive drugs – A blind, randomized, controlled clinical trial

BackgroundArterial hypertension is a systemic condition that affects about 35% of the world population. The drugs that are used for its control can produce hyposalivation. This work evaluated the effect of photobiomodulation on salivary flow rate, salivary pH, total protein concentration, and calcium concentration in individuals using antihypertensive medications. Material and methods41 subjects were randomly allocated in one of two groups: control (placebo) and photobiomodulation. The subjects had their salivary glands (20 sites) irradiated with a laser emitting at 808 nm, 4J/site once a week for 4 weeks and had their salivary flow measured before and after the whole treatment. ResultsThe intragroup analysis (before and after treatment) shows a significant difference for both non-stimulated and stimulated salivary flow in the photobiomodulation group (p = 0.0007 and p = 0.0001, respectively). Comparing the placebo with the photobiomodulation group, significant differences were found for both non-stimulated (p = 0.0441) and stimulated salivary flow (p = 0.0441) after the treatment. No significant differences were found in pH, total protein concentration, calcium concentration. ConclusionDespite the usage of drugs that influence the nervous system and typically result in a reduction of saliva production, photobiomodulation demonstrated a remarkable ability to enhance saliva production by a significant 75%.

LEDT and Idebenone treatment modulate autophagy and improve regenerative capacity in the dystrophic muscle through an AMPK-pathway.

Considering the difficulties and challenges in Duchenne muscular dystrophy (DMD) treatment, such as the adverse effects of glucocorticoids, which are the main medical prescription used by dystrophic patients, new treatment concepts for dystrophic therapy are very necessary. Thus, in this study, we explore the effects of photobiomodulation (PBM; a non-invasive therapy) and Idebenone (IDE) treatment (a potent antioxidant), applied alone or in association, in dystrophic muscle cells and the quadriceps muscle, with special focus on autophagy and regenerative pathways. For the in vitro studies, the dystrophic primary muscle cells received 0.5J LEDT and 0.06μM IDE; and for the in vivo studies, the dystrophic quadriceps muscle received 3J LEDT and the mdx mice were treated with 200mg/kg IDE. LEDT and IDE treatment modulate autophagy by increasing autophagy markers (SQSTM1/p62, Beclin and Parkin) and signaling pathways (AMPK and TGF-β). Concomitantly, the treatments prevented muscle degeneration by reducing the number of IgG-positive fibers and the fibers with a central nucleus; decreasing the fibrotic area; up-regulating the myogenin and MCH-slow levels; and down-regulating the MyoD and MHC-fast levels. These results suggest that LEDT and IDE treatments enhance autophagy and prevented muscle degeneration in the dystrophic muscle of the experimental model. These findings illustrate the potential efficacy of LEDT and IDE treatment as an alternative therapy focused on muscle recovery in the dystrophic patient.

Brain–gut photobiomodulation restores cognitive alterations in chronically stressed mice through the regulation of Sirt1 and neuroinflammation

BackgroundChronic stress is an important risk factor for the development of major depressive disorder (MDD). Recent studies have shown microbiome dysbiosis as one of the pathogenic mechanisms associated with MDD. Thus, it is important to find novel non-pharmacological therapeutic strategies that can modulate gut microbiota and brain activity. One such strategy is photobiomodulation (PBM), which involves the non-invasive use of light. Objective/hypothesisBrain-gut PBM could have a synergistic beneficial effect on the alterations induced by chronic stress. MethodsWe employed the chronic unpredictable mild stress (CUMS) protocol to induce a depressive-like state in mice. Subsequently, we administered brain-gut PBM for 6 min per day over a period of 3 weeks. Following PBM treatment, we examined behavioral, structural, molecular, and cellular alterations induced by CUMS. ResultsWe observed that the CUMS protocol induces profound behavioral alterations and an increase of sirtuin1 (Sirt1) levels in the hippocampus. We then combined the stress protocol with PBM and found that tissue-combined PBM was able to rescue cognitive alterations induced by CUMS. This rescue was accompanied by a restoration of hippocampal Sirt1 levels, prevention of spine density loss in the CA1 of the hippocampus, and the modulation of the gut microbiome. PBM was also effective in reducing neuroinflammation and modulating the morphology of Iba1-positive microglia. LimitationsThe molecular mechanisms behind the beneficial effects of tissue-combined PBM are not fully understood. ConclusionsOur results suggest that non-invasive photobiomodulation of both the brain and the gut microbiome could be beneficial in the context of stress-induced MDD.

Effectiveness of photobiomodulation in reducing xerostomia and hyposalivation in patients with Sjogren’s syndrome: an integrative review

Effectiveness of photobiomodulation in reducing xerostomia and hyposalivation in patients with Sjogren’s syndrome: an integrative review

The Effect of Transcranial Photobiomodulation for Motor Performance Improvement in Patients with Brain Disorders

Background: Transcranial photobiomodulation (PBM) therapy has emerged as a promising alternative therapeutic option for the management of neurological and psychiatric disorders. However, the underlying mechanisms of PBM therapy and its effects on motor performance in brain disorders are not yet fully understood. The aim of this literature review is to provide a more detailed and evidence-based explanation of the rationale and intent behind the correlation between PBM therapy and its effects on motor performance in brain disorders. Methods: A literature search was performed in the databases "PubMed/Medline", "Scopus," and "Google Scholar" for all relevant English language papers. A combination of different keywords was used for the database search. Video articles, patents, review articles, book chapters, articles using other transcranial methods, non-transcranial PBM, and case reports were excluded. Results: Out of the 2174 papers, 18 addressed the effect of PBM on motor performance. Among these, four studies were on ischemic stroke models and individuals with stroke, six studies on models associated with traumatic brain injury (TBI), five studies on models associated with neurodegenerative diseases and Parkinson's disease, and four studies related to models and patients with central nervous system inflammation. All studies have shown that motor parameters improve with PBM. In two studies on healthy individuals, 65 showed improvement in motor function and 16 showed improvement in motor evoked potential. In most studies (n=10), the wavelength used was between 800 and 900 nm. Near-infrared or LED continuous light was used in most studies. However, two studies compared the effects of pulsed and continuous waves and found the superiority of pulsed over continuous waves. Conclusions: PBM therapy appears to be useful in brain injury, inducing changes at the behavioral, motor, cellular, and chemical levels. Recent studies suggest that PBM therapy may have potential benefits in improving motor performance in brain disorders, including stroke, traumatic brain injury, Parkinson's disease, and demyelination. However, further research is needed to determine the optimal parameters for PBM therapy and to investigate its effects on motor function in different brain disorders. Overall, PBM therapy appears to be a promising therapeutic option for brain injury and warrants further investigation.

The effect of photobiomodulation with 830-nm LED on corneal alkali burnt rat model.

The effect of photobiomodulation with 830-nm LED on corneal alkali burnt rat model.

TRANSCRANIAL PHOTOBIOMODULATION IN NEUROLOGICAL AND PSYCHIATRIC PRACTICE: FUNDAMENTAL AND CLINICAL ASPECTS

Photobiomodulation is a relatively young medical technology that integrates the efforts of physicists, engineers and specialists in the field of biomedicine and includes various methods of light exposure to cells and tissues of the body. The main options for such effects are light radiation of the visible and IR spectrum generated by LED sources, and low-intensity laser radiation (LILI), which requires the use of lasers with special characteristics. In recent years, there has been an avalanche of interest among neurologists and psychiatrists in transcranial photobiomodulation, However, a systematization of empirical data and the fundamental foundations of technology is required. On this basis, the purpose of the review is to integrate ideas about the molecular-cellular and systemic effects of transcranial photobiomodulation and the prospects for its application in neurological and psychiatric practice. We have shown that intensive research in the field of studying the biological effects of low–intensity laser radiation, red and infrared light, which made it possible to decipher the main ways of responding to it at the molecular, cellular and tissue levels, created prerequisites for the formation of a new synthetic scientific direction - photobiomics. This translational discipline is focused on the development of pathogenetically sound technologies for the treatment of diseases of various profiles, including neurological and mental pathology. The results of experimental and clinical studies presented in the literature indicate the effectiveness of photobiomodulation in depression and post-traumatic stress disorder, nevertheless, extensive trials and meta-analyses are advisable for their full inclusion in international clinical recommendations.

Photobiomodulation alleviates Burning Mouth Syndrome pain: Immediate and weekly outcomes explored.

To assess immediate and weekly effects of photobiomodulation (PBM) on BMS patients. Thirty BMS patients were treated intra-orally with photobiomodulation 940(±10) nm (InGaAsP) 3 W, semi-conductor diode, weekly, for up to 10 weeks. Pain intensity, measured using the Visual Analogue Scale (VAS), and characteristics were recorded immidiately after each treatment, along with a weekly average VAS. Immediate mean VAS score decreased from a starting score of 7.80 ± 1.83 to 2.07 ± 2.55 (p < 0.001). The mean weekly VAS score for the week after the final treatment session was higher (5.73 ± 2.80, p < 0.001) than the immediate response, but still significantly lower than the starting score (p = 0.017). We observed a trend of pain improvement with more treatments, but this was only statistically significant up to the third treatment. Male gender and unilateral pain correlated with better PBM efficacy (p = 0.017, 0.022, respectively). PBM provides significant immediate pain relief for BMS patients after each treatment; however, the efficacy decreases notably over the following week. A trend of increasing pain relief across treatments was observed, statistically significant up to the third treatment.

Dosimetry in cranial photobiomodulation therapy: effect of cranial thickness and bone density

This research aims to examine the influence of human skull bone thickness and density on light penetration in PBM therapy across different wavelengths, focusing on how these bone characteristics affect the absorption of therapeutic light. Analyses explored the effect of skull bone density and thickness on light penetration in PBM, specifically using Low-Level Laser Therapy (LLLT) for efficacy prediction. Measurements of bone thickness and density were taken using precise tools. This approach emphasizes LLLT's significance in enhancing PBM outcomes by assessing how bone characteristics influence light penetration. The study revealed no significant correlation between skull bone density and thickness and light penetration capability in photobiomodulation (PBM) therapy, challenging initial expectations. Wavelengths of 405 nm and 665 nm showed stronger correlations with bone density, suggesting a significant yet weak impact. Conversely, wavelengths of 532 nm, 785 nm, 810 nm, 830 nm, 980 nm, and 1064 nm showed low correlations, indicating minimal impact from bone density variations. However, data variability (R2 < 0.4) suggests that neither density nor thickness robustly predicts light power traversing the bone, indicating penetration capability might be more influenced by bone thickness at certain wavelengths. The study finds that the effectiveness of photobiomodulation (PBM) therapy with bone isn't just based on bone density and thickness but involves a complex interplay of factors. These include the bone's chemical and mineral composition, light's wavelength and energy dose, treatment duration and frequency, and the precise location where light is applied on the skull.

A study of the biological effects of low-level light.

Low-level light therapy (LLLT), also known as photo biomodulation (PBM), is a type of optical therapy that uses red or near-infrared lasers or light-emitting diodes (LEDs) for medical treatment. The laser wavelengths involved in PBM typically range between 600-700nm and 780-1100nm, with power densities ranging between 5 mW/cm2 and 5 W/cm2. PBM is a series of biochemical cascades exhibited by biological tissues after absorbing a certain amount of energy from light. PBM has been widely used in clinical practice in the past 20years, and numerous clinical trials have demonstrated its biological efficacy. However, the underlying mechanisms have not yet been fully explored. In this paper, we have summarized the research into PBM over the past two decades, to identify the important mechanisms of the biological effects of PBM from the perspective of molecular mechanisms, cellular levels, and tissue changes. We hope our study provide a theoretical basis for future investigations into the underlying mechanisms.

Photobiomodulation versus corticosteroid in the management of erosive oral lichen planus: a randomized controlled clinical trial

BackgroundOral lichen planus (OLP) is a chronic illness of immune origin that is typically treated with corticosteroids as a gold standard therapy. Photobiomodulation (PBM) may represent an alternative remedy that has the potential to treat a variety of pathological conditions by alleviating pain, reducing inflammation, and promoting tissue healing without the drawbacks of steroid therapies. Thus, the aim of the current study was to compare the effect of photobiomodulation to topical 0.1% triamcinolone acetonide on erosive oral lichen planus.MethodsThis randomized controlled clinical trial involved 44 patients complaining of erosive oral lichen planus. Patients were assigned to one of two groups: control group (n = 22) received 0.1% topical triamcinolone acetonide three times daily with miconazole oral gel once daily for 4 weeks, and photobiomodulation group (n = 22) received laser therapy by 980 nm diode laser utilizing output power 300 mW twice weekly for 5 weeks (a total of 10 sessions). The evaluation of patients was performed at baseline, 6 weeks, and 12 weeks postoperatively in terms of pain, clinical scores, and biochemical evaluation of salivary malondialdehyde levels. All recorded data were analyzed using Mann–Whitney test to compare the two studied groups regarding pain, lesion size, and salivary levels of malondialdehyde. Friedman test, followed by post hoc test, was used for comparison of the data within the same group along the 3 periods at baseline, 6 weeks, and 12 weeks.ResultsBoth groups showed significant improvement in pain and clinical scores, with no statistical difference between them. Moreover, there was a significant improvement in salivary malondialdehyde levels for both groups, with no significant difference between them.ConclusionsPhotobiomodulation could be a promising therapeutic modality for management of erosive oral lichen planus without the side effects of steroid therapy. The salivary malondialdehyde level could be used as a biomarker to evaluate the disease severity and its response to the treatment.Trial registrationThe study has been registered at ClinicalTrials.gov (NCT05951361) (19/07/2023).

Photobiomodulation Increases M2-Type Polarization of Macrophages by Inhibiting Versican Production After Spinal Cord Injury.

Spinal cord injury (SCI) is a catastrophic accidence with little effective treatment, and inflammation played an important role in that. Previous studies showed photobiomodulation (PBM) could effectively downregulate the process of inflammation with modification of macrophage polarization after SCI; however, the potential mechanism behind that is still unclear. In the presented study, we aimed to investigate the effect of PBM on the expression level of versican, a matrix molecular believed to be associated with inflammation, and tried to find the mechanism on how that could regulate the inflammation process. Using immunofluorescence technique and western blot, we found the expression level of versican is increased after injury and markedly downregulated by irradiation treatment. Using virus intrathecal injection, we found the knock-down of versican could produce the effect similar to that of PBM and might have an effect on inflammation and macrophage polarization after SCI. To further verify the deduction, we peptide the supernatant of astrocytes to induce M0, M1, and M2 macrophages. We found that the versican produced by astrocytes might have a role on the promotion of M2 macrophages to inflammatory polarization. Finally, we investigated the potential pathway in the regulation of M2 polarization with the induction of versican. This study tried to give an interpretation on the mechanism of inflammation inhibition for PBM in the perspective of matrix regulation. Our results might provide light on the inflammation regulation after SCI.