Photobiomodulation, photomedicine, and laser surgery最新文献

Background: Oral mucositis (OM) is a frequent and debilitating adverse effect of cancer treatments, primarily mediated by oxidative stress and inflammatory pathways involving reactive oxygen species (ROS) and nitric oxide. Photobiomodulation (PBM) therapy has emerged as a potential intervention to mitigate OM severity by regulating these mechanisms. This review examines the influence of PBM on salivary nitrite concentrations-a key biomarker of oxidative stress-in patients with OM. Methods: A systematic literature search was conducted across PubMed and the Cochrane Library, encompassing clinical trials published up to June 2025. Included studies investigated the effects of PBM on salivary nitrite levels in patients receiving anticancer therapy. Methodological quality was assessed using the Revised Cochrane Risk of Bias tool (RoB 2.0). Results: Three studies satisfied the inclusion criteria. Although variations existed among the studies regarding anticancer treatment modalities and PBM irradiation parameters, all consistently reported a reduction in salivary nitrite levels following PBM therapy. Conclusion: PBM therapy appears effective in alleviating OM severity, potentially attributable to its capacity to decrease salivary nitrite concentrations. Additional research is warranted to validate these preliminary findings and optimize PBM protocols for clinical implementation.

Background: Diabetes mellitus (DM) is a global health concern, with 90% of cases diagnosed as type 2 DM (DM2). Objective: We evaluated the effects of photobiomodulation (PBM) plus adipose-derived stem (ADS) cells, alone and together, during the inflammation (day 4) and proliferation (day 8) stages of the wound healing process (WHP) in an infected ischemic wound model in DM2 rats. Stereological parameters and immunohistological assessments of M1 and M2 macrophage phenotypes, as well as mRNA expression levels of four genes, were assessed. Materials and Methods: We assigned 48 rats to 4 groups: control, PBM, ADS, and PBM+ADS. Results: On day 4, the treatment groups had significantly reduced neutrophil, macrophage, and M1 counts compared to the control group (all p < 0.001). PBM+ADS showed the greatest reduction (p < 0.001). The treatment groups had higher fibroblast and M2 counts (p < 0.001), with PBM+ADS showing the largest increase (p < 0.01). Vascular length was significantly greater in the PBM+ADS and PBM groups (p < 0.001), with PBM+ADS showing the highest increase (p < 0.001). New epidermis and dermis volumes were significantly higher in all treatment groups (p < 0.001), with PBM+ADS showing the greatest improvements (p < 0.001). On day 8, neutrophil, macrophage, and M1 counts remained significantly lower in all treated groups (p < 0.001), with PBM+ADS showing the most reduction. Fibroblasts and M2 counts remained elevated, with PBM+ADS having the highest values (p < 0.001). Vascular length, epidermis, and dermis volumes increased significantly in the PBM+ADS group (all p < 0.001). There were significant increases in basic fibroblast growth factor, vascular endothelial growth factor A, stromal cell-derived factor-1α, and hypoxia-inducible factor 1-alpha in all treatment groups (all p < 0.001), especially the PBM+ADS and PBM groups. Conclusion: Although PBM outperformed ADS in enhancing WHP in a DM2 rat model, the combination of PBM+ADS showed the best results.

Objective: To determine how Erbium-doped yttrium aluminum garnet (Er:YAG) laser irradiation affects the proliferation and transcriptional programs of MLO-Y4 osteocyte-like cells. Background: Although Er:YAG lasers are widely used in periodontal hard tissue therapy, how they affect osteocytes remain elusive. Materials and Methods: MLO-Y4 cells were seeded before 72 h Er:YAG laser irradiation at energy fluences of 3.1, 6.0, and 8.9 J/cm². Cell surface temperature and Hspa1a expression were measured to evaluate thermal effects. Cell proliferation and cytotoxicity were assessed by the Cell Counting Kit-8 (CCK-8) and lactate dehydrogenase (LDH) assays. RNA sequencing (RNA-seq) was performed 6 h after 6.0 J/cm² laser irradiation versus nonirradiated controls. Results: According to surface temperature and Hspa1a expression, no major thermal effects were observed at 6.0 J/cm². The CCK-8 assay revealed significantly increased proliferative activity, although LDH levels were slightly but significantly increased at 6.0 J/cm² laser irradiation. RNA-seq identified 337 differentially expressed genes (DEGs). Expression of mechanical stimulation-associated genes, including Epha2, Itga5, and Tcf7, was highly upregulated in the laser-irradiated cells. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed upregulation of the PI3K-Akt signaling pathway in the laser-irradiated cells. Upregulated DEGs belonged to the "euchromatin" cellular component Gene Ontology term in the laser-irradiated cells. Gene set enrichment analysis showed enrichment of the Transforming Growth Factor Beta (TGF-β) signaling gene set and downregulation of mechanistic target of rapamycin (mTORC1) signaling gene set in the laser-irradiated cells. Conclusion: Er:YAG laser irradiation at 6.0 J/cm² promotes MLO-Y4 osteocyte-like cell proliferation via altering gene expression, possibly by activating PI3K-Akt and TGF-β signaling while suppressing mTORC1 signaling.

Background: Photobiomodulation Valeda (PBM-Valeda) is a novel therapeutic approach for dry age-related macular degeneration (AMD). The primary objective of this short-term study was to conduct an analysis of best-corrected visual acuity (BCVA) and evaluate of biomarkers using state-of-the-art high-resolution imaging with swept-source optical coherence tomography OCT (SS-OCT) and OCT angiography (SS-OCTA) in dry AMD patients treated with PBM. Materials and Methods: This prospective, noncomparative, interventional case series pilot study examined the following biomarkers before and after PBM treatment: BCVA, central macular thickness (CMT), subfoveal choroidal thickness (SCT), capillary density (CD), avascular area of the superficial plexus (AASP), and avascular area of the deep plexus (AADP). All parameters were assessed at baseline and 1 week after treatment. A questionnaire (exploratory, not a validated endpoint) was carried out at the end of the treatment. Results: The study included 25 eyes (19 patients), predominantly in the Age-Related Eye Disease Study category II. A statistically significant change in BCVA was observed (p = 0.001). No statistically significant changes were observed in CMT, SCT, CD, AASP, or AADP (p > 0.05). The treatment was well tolerated, with few mild side effects, and no patient developed wet AMD. Conclusion: PBM-Valeda therapy demonstrated a favorable short-term safety profile in patients with dry AMD. The key finding of this study was the stability of SS-OCT and SS-OCTA biomarkers (CMT, SCT, CD, AASP, and AADP), with no adverse changes observed. These results reinforce the short-term safety of PBM. Reported side effects were minimal, with no evidence of retinotoxicity. This is the first prospective study to explore SS-OCT and SS-OCTA biomarkers in patients with dry AMD undergoing PBM therapy, providing preliminary safety data for future controlled trials.

Background: Laser hemorrhoidoplasty (LHP) has emerged as a minimally invasive alternative to excisional hemorrhoidectomy, but data remain heterogeneous, particularly regarding energy settings and safety outcomes. Methods: This multicenter retrospective cohort included 100 patients with symptomatic grade III hemorrhoids treated with LHP across six Brazilian centers between January 2021 and August 2023. Primary outcomes were postoperative pain (Visual Analog Scale-VAS), proctological symptoms (Proctological Symptoms Scale-PSS), and complications. Associations between total laser energy and complications were analyzed using multivariable logistic regression. Results: Median VAS peaked at 3.0 on day 7 and declined to near-complete remission by day 14, remaining minimal up to 1 year. PSS scores improved in parallel, reaching zero from day 30. The 30-day complication rate averaged 19.7%, peaking at 27% on day 14, with a cumulative per-patient rate of 44%. Most complications were mild (edema, skin tags), and only four patients required reintervention. Higher total energy was associated with increased complications from day 14 onwards, although the clinical effect was modest. Adjunctive CO₂ laser excision of skin tags (n = 49) did not increase morbidity. Conclusions: LHP proved safe and effective for grade III hemorrhoids, ensuring early pain relief and symptom resolution with high satisfaction. Energy standardization may help minimize risks, and adjunctive CO₂ skin-tag excision appears feasible without added morbidity.

Objective: Temporomandibular joint disorders (TMDs) are multi-factorial conditions with a chronic progression that affects individual's quality of life (QOL). Background: Currently, there is no definitive treatment for TMDs. Few clinical trials have investigated the potential effects of Photobiomodulation therapy on the acupuncture points on these disorders. Methods: Twenty patients with TMD, referred to the facial pain clinic at Semnan Faculty of Dentistry, were randomly assigned into two groups: treatment (n = 10) and placebo (n = 10).Treatment group received low-power Photobiomodulation therapy for 3 min at each of 10 acupuncture points, including GB20, SI19, ST6, ST7, and LI4. The placebo group received only the guiding light of the device on the same points. Treatment consisted of 10 sessions (twice a week). QOL was assessed using the OHIP-14 and SF-36 questionnaires at the beginning and end of treatment. Result: Significant differences were observed between the treatment and placebo groups according to pain relief and maximum mouth opening (p < 0.05; Mann-Whitney). However, no significant difference was observed between the groups for the QOL using OHIP-14. In contrast, the SF-36 showed significant improvements in the physical health subscale in the treatment group. Conclusions: Photobiomodulation therapy on the acupuncture is a complementary, noninvasive therapy that may benefit patients with TMDs.

Background: Rheumatoid arthritis (RA) is a persistent inflammatory condition that results in joint deterioration and impairment. A noninvasive treatment option that has shown promise is photobiomodulation therapy (PBMT), but the optimal energy density for RA management is not well established. Objective: This study aims to assess the therapeutic efficacy of PBMT utilizing varying energy densities on RA in male rats, in comparison with methotrexate treatment. Methods: A case-control study was conducted on 48 male rats randomly assigned to six groups: Group I is the negative control, Group II is the RA positive control, Group III is the RA + PBMT 36 J/cm², Group IV is the RA + PBMT 54 J/cm², Group V is the RA + PBMT 72 J/cm², and Group VI is the RA plus methotrexate. RA was induced in all groups except Group I. Treatments were applied over a defined period. Outcomes included paw thickness and biochemical markers: superoxide dismutase (SOD), interleukin-6 (IL-6), interleukin-1β (IL-1β), malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), and rheumatoid factor. Results: All PBMT-treated groups showed significant reductions in paw thickness, and pro-inflammatory indicators were compared with the RA positive control (p < 0.05). PBMT at 54 J/cm² (Group IV) demonstrated the most pronounced anti-inflammatory effect, comparable with methotrexate. Oxidative stress marker MDA decreased significantly, while SOD levels increased in all PBMT groups, particularly in Group IV. Conclusion: PBMT at an energy density of 54 J/cm² appears optimal in mitigating inflammation and oxidative stress in RA, providing a potential non-pharmacologic adjunct to conventional therapy.

Objective: The current study sought to explore the impact of a novel noninvasive treatment called transcranial photobiomodulation (PBM) on resting-state functional connectivity (rsFC) of the cerebellum in individuals with a history of repetitive head acceleration events (RHAEs). Background: RHAEs are associated with cumulative neurological compromise, including chronic alterations in rsFC; however, few treatments have been investigated to mitigate these effects. A recent study by our team demonstrated that PBM treatment led to improvements in measures of balance and motor function in adults with RHAE exposure. Due to the cerebellum's role in motor functioning and its connectivity with cerebral regions targeted by PBM, we sought to examine changes in the rsFC of the cerebellum following PBM treatment. Methods: Thirty individuals with RHAE used an at-home PBM headset with an intranasal cannula for 20 min every other day for a period of 8-10 weeks. A total of 240 J/cm² of red and near-infrared light was administered to cortical nodes of the default mode network (DMN) and subcortical structures in each session. Using resting-state functional magnetic resonance imaging, rsFC was measured before and after treatment in 11 cerebellar seed regions associated with the DMN, salience network (SN), and frontoparietal network (FPN). Results: We observed an overall decrease in between-network connectivity and an increase in within-network connectivity after PBM treatment, particularly in the SN and FPN. Conclusions: These results suggest that PBM may improve network efficiency of the cerebellum by regulating overactive connections and increasing network segregation.

Background: Photobiomodulation (PBM) therapy involves the use of low-dose, nonionizing light to reduce pain and inflammation, promote wound healing, and enhance tissue regeneration. PBM-based therapy of various dental conditions is associated with improved treatment outcomes. This study aims to critically review the literature to highlight the underlying molecular biological mechanisms and clinical applications of PBM in modern dental practice. Methods: This critical review employed literature search in PubMed/Medline, Google Scholar, and ScienceDirect databases to determine biological basis of PBM with a particular focus on its clinical dental applications. English literature published in the past 25 years were eligible for inclusion. Selected studies were analyzed to evaluate the therapeutic biochemical effects of PBM, with a focus on its dental applications. Results: PBM exerts its biological effects by influencing cytochrome c oxidase, increasing adenosine triphosphate, and improving DNA replication and RNA transcription. Various transcription factors and signaling pathways are involved through the activation of secondary messengers such as reactive oxygen species, nitric oxide, and cyclic adenosine monophosphate. The favorable biological effects of PBM can be beneficial for various dental applications in pulp therapy, management of postsurgical complications, and temporomandibular joint disorders. Conclusions: PBM represents a promising and effective treatment modality for the management of several challenging dental problems in the pediatric and adult populations, offering improved treatment outcomes, namely enhanced wound healing and reduced inflammation. Further research is recommended to optimize technical settings and standardize current protocols in the aim of enhancing clinical outcomes, exploring more applications, and improving patient satisfaction.

Introduction: Cisplatin (Cis), a key cancer chemotherapy drug, faces limitations such as dose-dependent side effects and resistance. Photobiomodulation therapy (PBMT) shows promise as an adjuvant therapy to enhance Cis efficacy and reduce side effects. Methods: A systematic review was conducted to evaluate the combined effects of PBMT and Cis on various cancers. After searching five databases using relevant keywords, nine studies were included, encompassing both in vitro and in vivo models. Results: Most in vitro studies showed a synergistic effect, with enhanced cancer cell inhibition, apoptosis induction, and reduced cell viability compared with Cis alone. The animal model confirmed these findings, showing PBMT mitigated Cis-induced acute renal failure. Conclusion: Mechanistically, PBMT may increase reactive oxygen species generation, cytochrome c release, modulate cellular metabolism, and involve the miR-124/STAT3 signaling pathway. Combining PBMT with Cis appears to be a safe and effective cancer treatment strategy, synergistically inhibiting cancer cell growth and reducing side effects. Further clinical trials are needed to validate these findings.