Fig 4 - uploaded by Luis De Taboada
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Effect of 810-nm laser on intracellular calcium in the cultured cortical neurons. A : Fluo4 (green) and nuclear Hoechst (blue) fluorescence in control neurons. B : Fluo4 (green) and nuclear Hoechst (blue) fluorescence in neurons treated with 3 J/cm 2 810-nm laser. Scale bar is 50 m m. C : Quantification by fluorescence plate reader of the mean red/ green fluorescence ratio values from nine wells. Error bars are SD. Ã P < 0.05 versus control.
Source publication
In the past four decades numerous studies have reported the efficacy of low level light (laser) therapy (LLLT) as a treatment for diverse diseases and injuries. Recent studies have shown that LLLT can biomodulate processes in the central nervous system and has been extensively studied as a stroke treatment. However there is still a lack of knowledg...
Citations
... In particular, the effect of NIR on brain tissue in vivo was studied: 808 nm light was found to activate NMDARs (Uozumi et al., 2010), protect cells from the destructive effect of high Ca 2+ concentration, promote the excretion of Ca 2+ from cells, and prevent excitotoxicity (Huang, Nagata, Tedford, & Hamblin, 2014). It was shown on neurons that green (Reece, Dholakia, Thomas, & Cottrell, 2008) and NIR (810 nm) light (Kharkwal et al., 2011) activated Ca 2+ influx in cells through a plasma membrane depolarization without affecting temperature. ...
... Golovynskyi et al., 2018). Also, it was shown on neurons that green (Reece et al., 2008) and NIR light of 810 nm with low fluences that do not cause any elevation in temperature (Kharkwal et al., 2011) is capable to activate intracel- After irradiation, the cells were cultured in medium for 24 hr, and then cell viability assay was performed. The data are presented as mean ± SD (N = 8); *p < 0.05 indicates a statistically significant difference evaluated in relation to control (Studentʼs t test) Shapiro, Homma, Villarreal, Richter, & Bezanilla, 2012;Thompson, Wade, Cadusch, Brown, & Stoddart, 2013). ...
Red and near‐infrared (NIR) light effect on Ca²⁺ ions flux through the influence on N‐methyl‐D‐aspartate receptors (NMDARs) and their functioning in HeLa cells was studied in vitro. Cells were irradiated by 650 and 808 nm laser light at different power densities and doses and the obtained effect was compared with that caused by the pharmacological agents. The laser light was found to elevate Ca²⁺ influx into cell cytoplasm in a dose‐dependent manner without changes of the NMDAR functioning. Furthermore, the light of both wavelengths demonstrated the ability to elevate Ca²⁺ influx under the pharmacological blockade of NMDARs and also might partially abolish the blockade enhancing Ca²⁺ influx after selective stimulation of the receptors with NMDA. Simultaneously, the light at moderate doses demonstrated a photobiostimulating effect on cells. Based on our experiments and data reported in the literature, we suggest that the low‐power visible and NIR light can instigate a cell membrane depolarization via nonthermal activation, resulting in the fast induction of Ca²⁺ influx into cells. The obtained results also demonstrate that NIR light can be used for nonthermal and nonpharmacological stimulation of NMDARs in cancer cells.
... In this study, using red and NIR lasers, an energy density of about 1.2 J/cm 2 was delivered on the prefrontal cortex. This optimal range of energy density received by the cortex was enough for effective photomodulation of neural cells, this fact was also reported by other studies [56,57]. In addition, there has been an increased interest in using the PW mode lights (especially, at 10-Hz) for tLLLT in recent years [27,58]. ...
Background and objective:
The application of transcranial low-level light/laser therapy (tLLLT) in the range of red to near-infrared (NIR) spectrum for psychological disorders is a new area that is attracting growing interest in recent years. The photomodulation effects of NIR and red coherent lights on the activity of cytochrome c oxidase in neuronal cells of brain have been recently introduced. This study, therefore, sought to compare the therapeutic effects of 10-Hz pulsed wave NIR (810 nm) laser with red (630 nm) laser using the same delivered energy density and Citalopram in rat chronic mild stress (CMS) model of depression and anxiety.
Materials and methods:
CMS procedures (for 4 weeks) were used to induce stress. GaAlAs diode laser with red and NIR wavelengths on 10-Hz pulsed wave (50% duty cycle) were used to perform tLLLT treatment for three weeks. An energy density of about 1.2 J/cm-(2) per each session was delivered through a light spot with a diameter of 3-mm to the prefrontal cortex for both wavelengths. Citalopram (10 mg/kg, Intraperitoneal) was administered for twenty-one consecutive days to the drug group.
Results:
The findings of the present study showed an increase in swimming and decrease in immobility time, for both NIR laser and Citalopram groups compared to the stress group in forced swimming test. Anxiety-like behaviors showed insignificant decrease in all treatment groups in elevated plus maze test. The induction of stress significantly increased serum cortisol levels and treatments with both red laser and Citalopram decreased it. Hyperglycemia induced by CMS returned to normal levels in all treatment groups. The assessment of body weight also showed a significant increase in NIR laser group compared to the stress group by the end of the experiment.
Conclusions:
This study showed that non-invasive tLLLT using 10-Hz pulsed NIR laser light was as effective as Citalopram and more effective than red laser in the treatment of depressive-like behaviors and may help improve tLLLT as an alternative non-pharmacological treatments of psychological disorders such as depression. Lasers Surg. Med. 48:695-705, 2016. © 2016 Wiley Periodicals, Inc.
... Therefore, the irradiant fluence to a brain was 2.2–5.4 J/cm 2 since the total fluence for skin was 36 J/cm 2. The range was consistent with our previous study in where cellular responses of primary cortical neurons to an 810-nm-laser irradiation showed some positive biomodulatory effects such as significant increase of calcium, ATP and mitochondrial membrane potential (MMP) with a laser dose of 3 J/cm 2[26]. In addition, the short period of laser irradiation (12 min) was also reasonable in terms of possible clinical application. ...
Transcranial low-level laser therapy (LLLT) using near-infrared light can efficiently penetrate through the scalp and skull and could allow non-invasive treatment for traumatic brain injury (TBI). In the present study, we compared the therapeutic effect using 810-nm wavelength laser light in continuous and pulsed wave modes in a mouse model of TBI.
TBI was induced by a controlled cortical-impact device and 4-hours post-TBI 1-group received a sham treatment and 3-groups received a single exposure to transcranial LLLT, either continuous wave or pulsed at 10-Hz or 100-Hz with a 50% duty cycle. An 810-nm Ga-Al-As diode laser delivered a spot with diameter of 1-cm onto the injured head with a power density of 50-mW/cm(2) for 12-minutes giving a fluence of 36-J/cm(2). Neurological severity score (NSS) and body weight were measured up to 4 weeks. Mice were sacrificed at 2, 15 and 28 days post-TBI and the lesion size was histologically analyzed. The quantity of ATP production in the brain tissue was determined immediately after laser irradiation. We examined the role of LLLT on the psychological state of the mice at 1 day and 4 weeks after TBI using tail suspension test and forced swim test.
The 810-nm laser pulsed at 10-Hz was the most effective judged by improvement in NSS and body weight although the other laser regimens were also effective. The brain lesion volume of mice treated with 10-Hz pulsed-laser irradiation was significantly lower than control group at 15-days and 4-weeks post-TBI. Moreover, we found an antidepressant effect of LLLT at 4-weeks as shown by forced swim and tail suspension tests.
The therapeutic effect of LLLT for TBI with an 810-nm laser was more effective at 10-Hz pulse frequency than at CW and 100-Hz. This finding may provide a new insight into biological mechanisms of LLLT.
... At 30J/cm 2 ; severe mitochondrial damage occurred, leading to a second large release of ROS and NO and presumably apoptosis and cytotoxicity (although this study did not make those measurements). 8 We also tested LLLT in two mouse models of TBI. In a closed head-impact model, the scalp is opened surgically and a weight dropped onto the exposed skull followed by scalp closure. ...
The overall goal is to solve substantial military medical problems by creating technologies that are useful to diagnose and care for soldiers, and by elucidating the mechanisms of organ trauma and diseases that particularly affect soldiers. To achieve this broad goal, we have undertaken projects focused on novel treatments of infectious diseases and physical trauma relevant to military personnel, technological improvements for trauma care, and new approaches to triage. Infectious Diseases. Our approach is based on our experience in developing novel photochemical methods of killing organisms using a combination of molecular delivery systems and light-activated dyes (photosensitizers). Trauma Care. Our approach to improving therapeutic interventions for trauma includes developing new tools for the medic/surgeons. Trauma Triage. Small, fieldable, non-invasive optical probes that assess trauma victims are being developed.
