Effect of hyperthermia on improving neutrophil restoration after intraperitoneal chemotherapy.

Purpose: Intraperitoneal (IP) chemotherapy has several benefits but also can have severe hematologic side effects. We compared the effects of hyperthermic intraperitoneal chemotherapy (HIPEC) and conventional IP chemotherapy on bone marrow suppression and evaluated whether HIPEC increased neutrophil recovery.Methods: HIPEC or IP chemotherapy was administered to ovarian cancer-bearing mice. Bone marrow progenitor cell colony-forming unit (CFU) count, serum cytokine levels, and peripheral leukocyte count after HIPEC and IP chemotherapy were compared.Results: Peripheral neutrophil count, cytokine (G-CSF and CXCL1/KC) levels, and bone marrow progenitor cell CFU count were significantly higher after HIPEC than after IP chemotherapy.Conclusions: Hyperthermia increased the serum neutrophil-recruiting cytokine levels and reduced the magnitude of chemotherapy-induced neutropenia. Thus, HIPEC improved neutrophil and bone marrow recovery compared with conventional IP chemotherapy.

Transforming Weakness into Strength: Photothermal-Therapy-Induced Inflammation Enhanced Cytopharmaceutical Chemotherapy as a Combination Anticancer Treatment.

A new synergistic treatment that combines photothermal therapy (PTT) and inflammation-mediated active targeting (IMAT) chemotherapy based on cytopharmaceuticals is developed. During PTT, the photothermal tumor ablation is accompanied by an inflammatory effect and upregulation of inflammatory factors at the tumor site, which may accelerate tumor regeneration. Moreover, PTT-induced inflammation can also recruit neutrophils (NEs) to the tumor site. To convert the disadvantages of PTT-induced inflammation into strengths, NEs are investigated as cytopharmaceuticals for IMAT chemotherapy to further inhibit the tumor recurrence after PTT due to the chemotaxis of NEs to the inflammatory sites. In this study, PEGylated gold nanorods (PEG-GNRs) are explored as the photothermal agent and paclitaxel-loaded cytopharmaceuticals of NEs as the IMAT chemotherapeutic agent. PTT is conducted at 72 h postinjection of PEG-GNRs, followed by cytopharmaceuticals for IMAT chemotherapy. It is demonstrated that the cytopharmaceuticals effectively accumulate in the tumor sites after PTT, which leads to a significant enhancement of antitumor efficacy and a reduction in systemic toxicity. These studies suggest that PTT-induced inflammation further enhances the chemotherapy of cytopharmaceuticals, and the combination of PTT and IMAT chemotherapy may be a promising synergistic strategy for targeted cancer therapy.

Photobiomodulation at Multiple Wavelengths Differentially Modulates Oxidative Stress In Vitro and In Vivo.

Photobiomodulation (PBM) is emerging as an effective strategy for the management of multiple inflammatory conditions, including oral mucositis (OM) in cancer patients who receive chemotherapy or radiotherapy. Still, the poor understanding of the mechanisms by which the light interacts with biological tissues and the heterogeneity of light sources and protocols employed worldwide significantly limits its applicability. Reactive oxygen species (ROS) are massively generated during the early phases of OM and play a major role in the pathogenesis of inflammation in general. Here, we report the results of a clinical and experimental study, aimed at evaluating the effect of laser light at different wavelengths on oxidative stress in vivo in oncologic patients suffering from OM and in vitro in two cell types abundantly present within the inflamed oral mucosa, neutrophil polymorphonuclear (PMN) granulocytes, and keratinocytes. In addition to standard ROS detection methods, we exploited a roGFP2-Orp1 genetically encoded sensor, allowing specific, quantitative, and dynamic imaging of redox events in living cells in response to oxidative stress and PBM. We found that the various wavelengths differentially modulate ROS production. In particular, the 660 nm laser light increases ROS production when applied either before or after an oxidative stimulus. In contrast, the 970 nm laser light exerted a moderate antioxidant activity both in the saliva of OM patients and in both cell types. The most marked reduction in the levels of ROS was detected in cells exposed either to the 800 nm laser light or to the combination of the three wavelengths. Overall, our study demonstrates that PBM exerts different effects on the redox state of both PMNs and keratinocytes depending on the used wavelength and prompts the validation of a multiwavelength protocol in the clinical settings.

Near infrared laser irradiation induces NETosis via oxidative stress and autophagy.

NETosis is a novel immune defense strategy in which neutrophil activation results in the formation of extracellular DNA/protein network which is able to kill microbial populations. NETosis can be induced in vitro by lipopolysaccharide (LPS) or phorbol myristate acetate (PMA). Due to the importance of NETosis in different physiological and pathological processes, photobiostimulation effect on this neutrophil activation mechanism has been investigated. Human granulocytes, isolated from venous blood of healthy donors, were stimulated with a diode laser emitting at 980 nm with an energy intensity ranging from 0 to 75 joules. After 3 h of laser stimulation, granulocytes were fixed and colored with crystal violet in order to assess the NETosis morphology while extracellular DNA produced has been quantified using Sytox Green fluorescent dye. To evaluate ROS production and autophagy role in photobiostimulation-induced NETosis, granulocytes were pre-treated with ROS scavengers (vitamin C, sodium pyruvate, L-NAME, sodium azide), and an autophagy inhibitor (wortmannin). Laser stimulation induced an energy-dependent neutrophil extracellular trap (NET) production in human granulocytes starting from 50-J laser intensity. ROS scavengers and the autophagy inhibitor were able to abrogate both morphological features of NETosis and extracellular DNA production without modifying the basal level of NETosis. Photobiostimulation induced an increase in NET production due to an increase in ROS levels and autophagy activation.

Ameliorative effects of fruit stem extract from Muscat Bailey A against chronic UV-induced skin damage in BALB/c mice.

This study analyzed fruit stem extract (MGFE) from Muscat Bailey A grape (Vitis labrusca × Vitis vinifera) for their ameliorative effects on Ultraviolet B (UVB)-induced skin damage in Balb/c mice. Well established in vivo assays were used to determine the biological effects of MGFE upon UVB irradiation of BALB/c mice. The results showed that treatment with MGFE recovered glutathione depletion, prevented lipid peroxidation of tissues and decreased the expression of DNA repair enzyme oxo guanine glycosylase-1. MGFE recovered the skin conditions in UVB-irradiated Balb/c mice. Moreover, MGFE inhibited dermal infiltration of inflammatory cells and reduced serum tumor necrosis factor alpha and interleukin-6 levels. Finally, MGFE treatment inhibited UVB-induced melanin formation and collagen fiber destruction through the inhibition of matrix metalloproteinase-1 expression. Through high-performance liquid chromatography analysis, catechin, epicatechin, and trans-resveratrol were found to be among the main active compounds present in MGFE. Taken together, these results indicated that MGFE has potentials as topical therapeutic materials against skin damage by inhibiting oxidative stress and inflammatory.

Extremely high-frequency electromagnetic radiation enhances neutrophil response to particulate agonists.

The growing use of extremely high-frequency electromagnetic radiation (EHF EMR) in information and communication technology and in biomedical applications has raised concerns regarding the potential biological impact of millimeter waves (MMWs). Here, we elucidated the effects of MMW radiation on neutrophil activation induced by opsonized zymosan or E. coli in whole blood ex vivo. After agonist addition to blood, two samples were prepared. A control sample was incubated at ambient conditions without any treatment, and a test sample was exposed to EHF EMR (32.9-39.6 GHz, 100 W/m2 ). We used methods that allowed us to assess the functional status of neutrophils immediately after exposure: oxidant production levels were measured by luminol-dependent chemiluminescence, and morphofunctional changes to neutrophils were observed in blood smears. Results revealed that the response of neutrophils to both agonists was intensified if blood was exposed to MMW radiation for 15 min. Neutrophils were intact in both the control and irradiated samples if no agonist was added to blood before incubation. Similarly, exposing suspensions of isolated neutrophils in plasma to MMW radiation enhanced cell response to both zymosan and E. coli. Heating blood samples was shown to be the primary mechanism underlying enhanced EHF EMR-induced oxidant production by neutrophils in response to particulate agonists. Bioelectromagnetics. 39:144-155, 2018. © 2017 Wiley Periodicals, Inc.

Apoptosis induced by low-level laser in polymorphonuclear cells of acute joint inflammation: comparative analysis of two energy densities.

Anti-inflammatory property of low-level laser therapy (LLLT) has been widely described in literature, although action mechanisms are not always clarified. Thus, this study aimed to evaluate apoptosis mechanisms in the LLLT anti-inflammatory effects on the arthritis experimental model in vivo at two different energy densities (3 and 30 Jcm-2). Arthritis was induced in mice by zymosan solution, animals were distributed into five groups, and morphological analysis, immunocytochemistry and gene expressions for apoptotic proteins were performed. Data showed an anti-inflammatory effect, DNA fragmentation in polymorphonuclear (PMN) cells and alteration in gene expression of proteins related to apoptosis pathways after LLLT. p53 gene expression increased at both energy densities, Bcl2 gene expression increased at 3 Jcm-2, and Bcl2 tissue expression decreased at 30 Jcm-2. In addition, apoptosis was restricted to PMN cells. Results suggest that apoptosis in PMN cells comprise part of LLLT anti-inflammatory mechanisms by disbalance promotion between expression of pro-apoptotic (Bax and p53) and anti-apoptotic (Bcl-2) proteins, with pro-apoptotic gene expression selectively in PMN cells.

Influence of the first radioactive iodine ablation on peripheral complete blood count in patients with differentiated thyroid cancer.

Radioactive iodine (RAI) is considered to be related with hematologic changes. This study aimed to evaluate influence of the first RAI ablation on peripheral complete blood count (CBC) in patients with differentiated thyroid cancer (DTC).Data of CBC at baseline and 6 months after RAI were obtained in 385 patients with DTC with approximately 3700 MBq I (ranging 2220-7585 MBq). Further comparison was done in 196 patients with 1-month postablation data available. Routine blood examinations were performed to determine impact of RAI on white blood cell (WBC), red blood cell (RBC), hemoglobin, platelet, neutrophil, lymphocyte, and monocyte in both sexes. Continuous variables were compared by paired t tests and independent samples t test, and categorical variables were compared by chi-square analysis. Data with repeated measurements were analyzed by analysis of variance.The first RAI after thyroidectomy was associated with mild, yet significant declines in WBC, platelet, and lymphocyte, which persisted for 6 months. One month after RAI, significant declines were found in all CBC, including RBC and hemoglobin (all P < 0.05). While CBC partly recovered 6 months after RAI, this follow-up CBC still demonstrated significant declines in WBC, platelet, and lymphocyte (all P < 0.05) without gender differences. Significant rises in RBC and hemoglobin in males and females were found. The decline of platelet in females was more obvious than in males at 3700 to 4440 MBq of RAI. On the contrary, the rises of RBC and hemoglobin in males were higher than in females. There were no significant complications during the follow-up.WBC and platelet decreased obviously 1 month after RAI. While they partly recovered 6 months after RAI, they were still lower than the baseline. However, RBC and hemoglobin transiently decreased at 1 month and then increased to levels even higher than baseline 6 months later. At 3700 to 4440 MBq of RAI, the decline of platelet in females was more obvious than in males. Yet, rises of RBC and hemoglobin in males were higher than in females. The risks associated with these changes are unlikely to outweigh the potential benefits of RAI in patients with DTC.

Low-level laser therapy stimulates the oxidative burst in human neutrophils and increases their fungicidal capacity.

Low-level laser therapy (LLLT) is known to enhance mitochondrial electron transfer and ATP production; thus, this study asked whether LLLT could stimulate the oxidative burst in human neutrophils (PMN) and improve their ability to kill microorganisms. Blood from healthy human subjects was collected and PMN were isolated from the samples. PMN were treated in vitro with 660 nm or 780 nm CW laser light at 40 mW power and increasing energies up to 19.2 J and were subsequently incubated with Candida albicans cells. Generation of hydroxyl radicals, hypochlorite anions and superoxide anions by PMN were checked using fluorescent probes and chemiluminescence assays; a microbicidal activity assay against C. albicans was also performed. LLLT excited PMN to a higher functional profile, which was translated as superior production of reactive oxygen species (ROS) and increased fungicidal capacity. The most efficacious energy was 19.2 J and, interestingly, the 660 nm light was even more efficacious than 780 nm at increasing the respiratory burst of PMN and the fungicidal capacity. Human neutrophils (PMN) were stimulated in vitro with 660 nm or 780 nm CW laser light at 40 mW of power and a total energy of 19.2 J. Low-level laser therapy (LLLT) excited PMN to a higher functional profile, which was translated as a superior production of reactive oxygen species (ROS) such as hydroxyl radicals (HO• ) and hypochlorite anions (ClO- ) (Figure) and increased fungicidal capacity against Candida albicans cells.

Neutrophil/Lymphocyte Ratio, Serum Endocan, and Nesfatin-1 Levels in Patients with Psoriasis Vulgaris Undergoing Phototherapy Treatment.

BACKGROUND Psoriasis is an autoimmune, inflammatory, and chronic disease. Recent studies have evaluated serum endocan and nesfatin-1 levels in patients with inflammatory disorders. The neutrophil-to-lymphocyte ratio (NLR) is an inflammatory marker currently used in many diseases. The aim of the present study was to evaluate NLR, serum endocan, and nesfatin-1 levels in psoriasis vulgaris before and after narrow-band ultraviolet B (NB-UVB) phototherapy treatment and compared to healthy controls. MATERIAL AND METHODS This study was conducted on a total of 88 cases, 39 of which had psoriasis vulgaris and 49 were healthy volunteers. Thirty-nine psoriasis vulgaris patients underwent NB-UVB phototherapy treatment for 3 months. NLR, serum endocan, and nesfatin-1 levels were measured in all psoriasis patients before and after NB-UVB phototherapy and in the control group. RESULTS Compared with the control group, neutrophil count and NLR were significantly higher (p<0.001) in psoriasis patients before NB-UVB phototherapy. Serum endocan levels were significantly correlated with disease activity before treatment. There was no significant difference in NLR, serum endocan, and nesfatin-1 levels in psoriasis patients before and after NB-UVB phototherapy (p>0.05). CONCLUSIONS The current study shows that NLR was higher in psoriasis vulgaris patients when compared with the control group, whereas serum endocan and nesfatin-1 levels were not significantly different. In addition, NB-UVB phototherapy did not affect NLR, serum endocan, or nesfatin-1 levels. Further larger-scale studies are required on this subject.

Comparative analysis of two low-level laser doses on the expression of inflammatory mediators and on neutrophils and macrophages in acute joint inflammation.

Synovial membrane inflammation plays an important role in osteoarthritis (OA) pathophysiology. The synovial tissue of patients with initial OA is characterized by mononuclear cell infiltration and the production of pro-inflammatory cytokines and other mediators of joint injury. The study aims to evaluate the effect of low-level laser therapy (LLLT) at doses of 2 and 4 J on joint inflammation in rats induced by papain through histopathological analysis, differential counts of inflammatory cells; gene expression of IL-1ß, IL-6, and IL-10; and TNF-α protein expression. Male Wistar rats (20) were randomly divided (5 animals each) into a negative control group, an inflammation injury positive control group, a 2-J LLLT group subjected to injury and treated with 2 J of LLLT, and a 4-J LLLT group subjected to injury and treated with 4 J of LLLT. The animals were subjected to joint inflammation (4 % papain solution) and treated with LLLT. On the day of euthanasia, articular lavage was collected and centrifuged. The supernatant was analyzed for TNF-α protein expression by ELISA and IL-1ß, IL-6, and IL-10 mRNA by RT-PCR. The joint tissue was also examined histologically. ANOVA with Tukey's post hoc test was used for comparisons. All data were expressed as means ± S.D. (p < 0.05). Both laser modalities were efficient in reducing cellular inflammation and decreasing the expression of IL-1ß and IL-6. However, the 2-J treatment led to more reduction in TNF-α than the 4-J treatment. A single application of LLLT with 2 J was more efficient in modulating inflammatory mediators and inflammatory cells.

The effect of low-level laser therapy on the healing of hard palate mucosa and the oxidative stress status of rats.

OBJECTIVE: The biostimulation effects of low-level laser therapy (LLLT) have been demonstrated recently. This study investigated the effects of LLLT on palatal mucoperiosteal wound healing and oxidative stress status in rats. MATERIAL AND METHOD: Forty-two male Wistar rats weighing 250-300 g were used in this study. A standardized full-thickness wound was created in the mucoperiosteum of the hard palates of the rats using a 3-mm-diameter biopsy punch. Treatment using a GaAlAs laser at a wavelength of 940 nm and a dose of 10 J/cm(2) was initiated after surgery and repeated on the 2nd, 4th, and 6th days post-surgery. Seven animals from each group were sacrificed on the 7th, 14th, and 21st days after surgery. Total antioxidant status and total oxidative status were measured in serum. RESULTS: The histopathological findings revealed reduced numbers of inflammatory cells on the 7th day, increased mitotic activity of fibroblasts on the 14th and 21st day, and the same degree of collagen synthesis and vascularization on the days 7, 14, and 21 in the LLLT group compared with the control group. No significant differences in total oxidative status and total antioxidant status were observed between the groups. CONCLUSION: LLLT using a GaAlAs laser at a wavelength of 940 nm and a dose of 10 J/cm(2) elicited a positive healing effect on palatal mucoperiosteal wounds likely via the induction of fibroblasts. The oxidative stress status was not affected by LLLT.

Can osteoarthritis be treated with light?

Osteoarthritis is becoming more problematic as the population ages. Recent reports suggest that the benefit of anti-inflammatory drugs is unimpressive and the incidence of side effects is worrying. Low-level laser (light) therapy (LLLT) is an alternative approach with no known side effects and with reports of substantial therapeutic efficacy in osteoarthritis. In this issue of Arthritis Research & Therapy, Alves and colleagues used a rat model of osteoarthritis produced by intra-articular injection of the cartilage-degrading enzyme papain to test 810-nm LLLT. A single application of LLLT produced significant reductions in inflammatory cell infiltration and inflammatory cytokines 24 hours later. A lower laser power was more effective than a higher laser power. However, more work is necessary before the title question can be answered in the affirmative.

Effect of low-level laser therapy on the expression of inflammatory mediators and on neutrophils and macrophages in acute joint inflammation.

INTRODUCTION: Inflammation of the synovial membrane plays an important role in the pathophysiology of osteoarthritis (OA). The synovial tissue of patients with initial OA is characterized by infiltration of mononuclear cells and production of proinflammatory cytokines and other mediators of joint injury. The objective was to evaluate the effect of low-level laser therapy (LLLT) operating at 50 mW and 100 mW on joint inflammation in rats induced by papain, through histopathological analysis, differential counts of inflammatory cells (macrophages and neutrophils), as well as gene expression of interleukin 1-beta and 6 (IL-1ß and IL-6), and protein expression of tumor necrosis factor alpha (TNFα). METHODS: Male Wistar rats (n = 60) were randomly divided into four groups of 15 animals, namely: a negative control group; an inflammation injury positive control group; a 50 mW LLLT group, subjected to injury and treated with 50 mW LLLT; and a 100 mW LLLT group, subjected to injury and treated with 100 mW LLLT. The animals were subject to joint inflammation (papain solution, 4%) and then treated with LLLT (808 nm, 4 J, 142.4 J/cm(2), spot size 0.028 for both groups). On the day of euthanasia, articular lavage was collected and immediately centrifuged; the supernatant was saved for analysis of expression of TNFα protein by enzyme-linked immunosorbent assay and expression of IL-1ß and IL-6 mRNA by real-time polymerase chain reaction. A histologic examination of joint tissue was also performed. For the statistical analysis, analysis of variance with Tukey's post-hoc test was used for comparisons between each group. All data are expressed as mean values and standard deviation, with P < 0.05. RESULTS: Laser treatment with 50 mW was more efficient than 100 mW in reducing cellular inflammation, and decreased the expression of IL-1ß and IL-6. However, the 100 mW treatment led to a higher reduction of TNFα compared with the 50 mW treatment. CONCLUSIONS: LLLT with 50 mW was more efficient in modulating inflammatory mediators (IL-1ß, IL-6) and inflammatory cells (macrophages and neutrophils), which correlated with the histology that showed a reduction in the inflammatory process.

Dual Effect of low-level laser therapy (LLLT) on the acute lung inflammation induced by intestinal ischemia and reperfusion: Action on anti- and pro-inflammatory cytokines.

BACKGROUND AND OBJECTIVE: It is unknown if pro- and anti-inflammatory mediators in acute lung inflammation induced by intestinal ischemia and reperfusion (i-I/R) can be modulated by low-level laser therapy (LLLT). STUDY DESIGN/MATERIAL AND METHODS: A controlled ex vivo study was developed in which rats were irradiated (660 nm, 30 mW, 0.08 cm² of spot size) on the skin over the right upper bronchus 1 hour post-mesenteric artery occlusion and euthanized 4 hours later. For pretreatment with anti-tumor necrosis factor (TNF) or IL-10 antibodies, the rats received either one of the agents 15 minutes before the beginning of reperfusion. METHODS: Lung edema was measured by the Evans blue extravasation and pulmonary neutrophils influx was determined by myeloperoxidase (MPO) activity. Both TNF and IL-10 expression and protein in lung were evaluated by RT-PCR and ELISA, respectively. RESULTS: LLLT reduced the edema (80.1 ± 41.8 µg g⁻¹ dry weight), neutrophils influx (0.83 ± 0.02 × 106 cells ml⁻¹), MPO activity (2.91 ± 0.60), and TNF (153.0 ± 21.0 pg mg⁻¹ tissue) in lung when compared with respective control groups. Surprisingly, the LLLT increased the IL-10 (0.65 ± 0.13) in lung from animals subjected to i-I/R. Moreover, LLLT (0.32 ± 0.07 pg ml⁻¹) reduced the TNF-α level in RPAECs when compared with i-I/R group. The presence of anti-TNF or IL-10 antibodies did not alter the LLLT effect on IL-10 (465.1 ± 21.0 pg mg⁻¹ tissue) or TNF (223.5 ± 21.0 pg mg⁻¹ tissue) in lung from animals submitted to i-I/R. CONCLUSION: The results indicate that the LLLT attenuates the i-I/R-induced acute lung inflammation which favor the IL-10 production and reduce TNF generation.

Effect of low-level laser therapy on experimental wounds of hard palate mucosa in mice.

Under general anesthesia and sterile conditions, incision wound was induced in the hard palate mucosa of adult male mice. The wounds of groups 1 and 2 were irradiated daily with He-Ne laser at 3 and 7.5 J/cm2 for 120 and 300 s, respectively, while the incision wound of group 3 not exposed served as controls. On day 3 of injury, the laser-treated wounds contained significantly lower neutrophils than the wounds in the control group. By day 7 after injury, the laser-treated wounds contained significantly more fibroblasts and at the same time contained significantly fewer macrophages. In conclusion, an acceleration of the wound healing process of experimental wounds in the hard palate mucosa of mice at low-level laser therapy with a He-Ne laser at energy densities of 3 and 7.5 J/cm2 was observed.

Photohardening restores the impaired neutrophil responsiveness to chemoattractants leukotriene B4 and formyl-methionyl-leucyl-phenylalanin in patients with polymorphic light eruption.

A failure to induce immune suppression after UV exposure has been implicated in the pathogenesis of polymorphic light eruption (PLE). This immunological resistance has been linked to an impaired neutrophil infiltration into the skin following UV exposure. Therapeutic photohardening can restore this abnormal neutrophil infiltration in PLE skin and is thought to be responsible for the prophylactic efficacy. The aim of this study was to elucidate the pathogenic mechanism of the described neutrophil deficiency in PLE. Peripheral blood neutrophil responses to the chemoattractants leukotriene B4 (LTB(4)) and formyl-methionyl-leucyl-phenylalanin (fMLP) were investigated in vitro. Samples from 10 patients with PLE before and after 6 weeks of photohardening therapy were assessed. Flow cytometry was used to measure the changes associated with neutrophil activation. We found a significantly reduced neutrophil responsiveness to LTB(4) and fMLP in PLE patients, which was restored to normal levels after phototherapy. Indeed, PLE neutrophil responsiveness to these two chemoattractants after (but not before) phototherapy was similar to that of age- and sex-matched healthy control subjects. This indicates that an abnormal chemotactic potential to neutrophils is a crucial factor in the pathogenesis of PLE. Normalization following photohardening may therefore account for the therapeutic efficacy by restoring UV-induced neutrophil skin infiltration. Our results reveal a completely novel pathogenic mechanism involved in PLE and offer unique targets for therapy.

Low intensity laser therapy (LILT) in vivo acts on the neutrophils recruitment and chemokines/cytokines levels in a model of acute pulmonary inflammation induced by aerosol of lipopolysaccharide from Escherichia coli in rat.

It has been suggested that low intensity laser therapy (LILT) acts on pulmonary inflammation. Thus, we investigate in this work if LILT (650nm, 2.5mW, 31.2mW/cm(2), 1.3J/cm(2), laser spot size of 0.08cm(2) and irradiation time of 42s) can attenuate edema, neutrophil recruitment and inflammatory mediators in acute lung inflammation. Thirty-five male Wistar rats (n=7 per group) were distributed in the following experimental groups: control, laser, LPS, LPS+laser and dexamethasone+LPS. Airway inflammation was measured 4h post-LPS challenge. Pulmonary microvascular leakage was used for measuring pulmonary edema. Bronchoalveolar lavage fluid (BALF) cellularity and myeloperoxidase (MPO) were used for measuring neutrophil recruitment and activation. RT-PCR was performed in lung tissue to assess mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin (IL-10), cytokine-induced neutrophil chemoattractant-1 (CINC-1), macrophage inflammatory protein-2 (MIP-2) and intercellular adhesion molecule-1 (ICAM-1). Protein levels in both BALF and lung were determined by ELISA. LILT inhibited pulmonary edema and endothelial cytoskeleton damage, as well as neutrophil influx and activation. Similarly, the LILT reduced the TNF-α and IL-1ß, in lung and BALF. LILT prevented lung ICAM-1 up-regulation. The rise of CINC-1 and MIP-2 protein levels in both lung and BALF, and the lung mRNA expressions for IL-10, were unaffected. Data suggest that the LILT effect is due to the inhibition of ICAM-1 via the inhibition of TNF-α and IL-1ß.

Monitoring of the effect of low-intensity laser radiation with constant pulse generation on neutrophil granulocytes in vitro.

We studied the effect of low-intensity laser radiation with constant pulse generation on bactericidal activity of neutrophilic granulocytes, in particular, on their capacity to form extracellular structures, so-called extracellular neutrophil traps. It was found that exposure to low-intensity laser radiation with constant pulse generation enhanced bactericidal activity of neutrophilic granulocytes, which manifested in the increase of the percent of neutrophils forming extracellular neutrophil traps.

The effect of phototherapy on neutrophils.

BACKGROUND: The role of phototherapy on neutrophils has not been reviewed previously. This novel and non-invasive therapeutic approach is of particular interest for potential use in the treatment of pathologic processes in dermatology and infectious diseases in which neutrophils are the primary culprit. OBJECTIVES: The primary aim of this study was to systematically review the role of phototherapy on neutrophils. METHOD: Original publications were identified through searches in PubMed, Medline, Ovid, and the Cochrane Library. Search terms used included "phototherapy and neutrophils," "light therapy and neutrophils," and "laser and neutrophils." Studies were selected based on the level of evidence-based research. RESULTS: The literature search revealed a total of 22 controlled laboratory studies that evaluated the role of phototherapy on neutrophils. Among the effects of phototherapy noted were increases in: the respiratory burst of neutrophils, apoptosis of polymorphonuclear cells, and plasma NO and iNOS mRNA. Other notable findings include decreased: number of neutrophils in areas of inflammation, ROS production, neutrophil anti-apoptotic factors, and IL-1beta concentration. Studies on PDT demonstrated neutrophilia and resultant decreased tumor growth. CONCLUSION: Evidence indicates that phototherapy has a significant impact on neutrophils, the effect of which varies according to the specific type of phototherapy. These findings have a variety of potential clinical applications including the treatment of various autoimmune conditions, inflammatory diseases, and cancers.