Stimulation of reactive oxygen species production by an antidepressant visible light source

A Comprehensive Systematic Review of the Effects of Photobiomodulation Therapy in Different Light Wavelength Ranges (Blue, Green, Red, and Near-Infrared) on Sperm Cell Characteristics in Vitro and in Vivo

Around 7% of the male population in the world are entangle with considerable situation which is known as male infertility. Photobiomodulation therapy (PBMT) is the application of low-level laser radiation, that recently used to increase or promote the various cell functions including, proliferation, differentiation, ATP production, gene expressions, regulation of reactive oxygen spices (ROS), and also boost the tissue healing and reduction of inflammation. This systematic review's main idea is a comprehensive appraisal of the literatures on subjects of PBMT consequences in four light ranges wavelength (blue, green, red, near-infrared (NIR)) on sperm cell characteristics, in vitro and in vivo. In this study, PubMed, Google Scholar, and Scopus databases were used for abstracts and full-text scientific papers published from 2003-2023 that reported the application of PBM on sperm cells. Criteria's for inclusion and exclusion to review were applied. Finally, the studies that matched with our goals were included, classified, and reported in detail. Also, searched studies were subdivided into the effects of four ranges of light irradiation, including the blue light range (400-500 nm), green light range (500-600 nm), red light range (600-780 nm), and NIR light range (780-3000 nm) of laser irradiation on human or animal sperm cells, in situations of in vitro or in vivo. Searches with our keywords results in 137 papers. After primary analysis, some articles were excluded because they were review articles or incomplete and unrelated studies. Finally, we use the 63 articles for this systematic review. Our category tables were based on the light range of irradiation, source of sperm cells (human or animal cells) and being in vitro or in vivo. Six% of publications reported the effects of blue, 10% green, 53% red and 31% NIR, light on sperm cell. In general, most of these studies showed that PBMT exerted a positive effect on the sperm cell motility. The various effects of PBMT in different wavelength ranges, as mentioned in this review, provide more insights for its potential applications in improving sperm characteristics. PBMT as a treatment method has significant effectiveness for treatment of different medical problems. Due to the lack of reporting data in this field, there is a need for future studies to assessment the biochemical and molecular effects of PBMT on sperm cells for the possible application of this treatment to the human sperm cells before the ART process.

Chondrogenic mRNA expression in prechondrogenic cells after blue laser irradiation

Low-level laser therapy (LLLT) has been used as a method for biostimulation. Cartilage develops through the differentiation of mesenchymal cells into chondrocytes, and differentiated chondrocytes in articular cartilage maintain cartilage homeostasis by synthesizing cartilage-specific extracellular matrix. The aim of this study is to evaluate the enhancement of chondrocyte differentiation and the expression levels of chondrogenic mRNA in prechondrogenic ATDC5 cells after laser irradiation. For chondrogenic induction, ATDC5 cells were irradiated with a blue laser (405 nm, continuous wave) at 100 mW/cm(2) for 180 s following incubation in chondrogenic differentiation medium. Differentiation after laser irradiation was quantitatively evaluated by the measurement of total collagen contents and chondrogenesis-related mRNAs. The total amount of collagen and mRNA levels of aggrecan, collagen type II, SOX-9, and DEC-1 were increased relative to those of a non-laser irradiated group after 14 days of laser irradiation. On the other hand, Ap-2alpha mRNA, a negative transcription factor of chondrogenesis, was dramatically decreased after laser irradiation. In addition, intracellular reactive oxygen species (ROS) were generated after laser irradiation. These results, for the first time, provide functional evidence that mRNA expression relating to chondrogenesis is increased, and Ap-2alpha is decreased immediately after laser irradiation. As this technique could readily be applied in situ to control the differentiation of cells at an implanted site within the body, this approach may have therapeutic potential for the restoration of damaged or diseased tissue.

Molecular mechanisms of cell proliferation induced by low power laser irradiation

Low power laser irradiation (LPLI) promotes proliferation of multiple cells, which (especially red and near infrared light) is mainly through the activation of mitochondrial respiratory chain and the initiation of cellular signaling. Recently, the signaling proteins involved in LPLI-induced proliferation merit special attention, some of which are regulated by mitochondrial signaling. Hepatocyte growth factor receptor (c-Met), a member of tyrosine protein kinase receptors (TPKR), is phosphorylated during LPLI-induced proliferation, but tumor necrosis factor alpha (TNF-alpha) receptor has not been affected. Activated TPKR could activate its downstream signaling elements, like Ras/Raf/MEK/ERK, PI3K/Akt/eIF4E, PI3K/Akt/eNOS and PLC-gamma/PKC pathways. Other two pathways, DeltaPsim/ATP/cAMP/JNK/AP-1 and ROS/Src, are also involved in LPLI-induced proliferation. LPLI-induced cell cycle progression can be regulated by the activation or elevated expressions of cell cycle-specific proteins. Furthermore, LPLI induces the synthesis or release of many molecules, like growth factors, interleukins, inflammatory cytokines and others, which are related to promotive effects of LPLI.

Mechanism of antimicrobial activity of CdTe quantum dots

The antimicrobial activity and mechanism of CdTe quantum dots (QDs) against Escherichia coli were investigated in this report. Colony-forming capability assay and atomic force microscopy (AFM) images show that the QDs can effectively kill the bacteria in a concentration-dependent manner. Results of photoluminescence spectrophotometry, confocal microscopy, and antioxidative response tests indicate that the QDs bind with bacteria and impair the functions of a cell's antioxidative system, including down-regulations of antioxidative genes and decreases of antioxidative enzymes activities. The oxidative damage of protein and lipid is also observed with thiobarbituric reacting substances and protein carbonyl assays, respectively. On the basis of these results, it is proposed that the mechanism of the antimicrobial activity of CdTe QDs involves QDs-bacteria association and a reactive oxygen species-mediated pathway. Thus, CdTe QDs could have the potential to be formulated as a novel antimicrobial material with excellent optical properties.

Chemiluminescent Analysis of Light-Irradiated Leukocytes as a Diagnostic Tool for Fast Identification of Pathological States

OBJECTIVE

Reactive oxygen species (ROS), mainly produced by polymorphonuclear neutrophils (PMN), are a significant part of host defense in pathologic states. We attempted to relate numbers of PMN and ROS generated within PMN to develop an alternative photochemical approach for evaluation of the potential of these cells to resist the development of inflammatory pathology.

BACKGROUND DATA

Lack of sensitivity to light has been reported in healthy cells, while sensitivity to light characterizes cell pathology.

METHODS

Human leukocytes from 34 donors were isolated and irradiated with a non-laser blue light (2 and 5 mW/cm(2) for 2 minutes), and a luminol-dependent chemiluminescence assay that reflects intracellular production of ROS was applied thereafter. The levels of basal chemiluminescence (BCL) were related to respective numbers of PMN.

RESULTS

A light-insensitive cluster was discovered within the total sample and was considered to be a discrete nonpathological group. Following elimination of this group, the rest of the sample was divided into three well-defined light-sensitive groups, which were attributed to various pathological states, and differed in PMN numbers and BCL counts. Within these groups the two traits were interrelated, and each PMN range was associated with a respective level of intracellular ROS.

CONCLUSIONS

Leukocyte responsiveness to light can be used for discrimination between pathological and nonpathological states and prognostic evaluation of pathological development. Patients exhibiting similar clinical symptoms could be divided into separate groups with potentially different outcomes. A novel definition of nonpathological states as well as the mechanism underlying the bell-shaped curve that delineates the relationship between PMN number and intracellular ROS is suggested in pathological states.

A reasonable mechanism for visible light-induced skin rejuvenation

In recent years, much research has been done in the field of non-ablative skin rejuvenation. This comes as a response to the continuous demand for a simple method of treating rhytides, UV exposure, and acne scars. Numerous researches involve visible light-pulsed systems (20-30 J/cm(2)). The mechanism of action is believed to be a selective heat-induced denaturalization of dermal collagen that leads to subsequent reactive synthesis (Bitter Jr., Dermatol. Surg., 26:836-843, 2000; Fitzpatrick et al., Arch. Dermatol., 132:395-402, 1996; Kauvar and Geronemus, Dermatol. Clin., 15:459-467, 1997; Negishi et al., Lasers Surg. Med., 30:298-305, 2002; Goldberg and Cutler, Lasers Surg. Med., 26:196-200, 2000; Hernandez-Perez and Ibeitt, Dermatol. Surg., 28:651-655, 2002). In this study, we suggest a different mechanism for photorejuvenation based on light-induced reactive oxygen species (ROS) formation. We irradiated collagen in vitro with a broadband of visible light (400-800 nm, 24-72 J/cm(2)) and used the spin trapping coupled with electron paramagnetic resonance spectroscopy to detect ROS. Irradiated collagen resulted in hydroxyl radicals formation. We propose, as a new concept, that visible light at the energy doses used for skin rejuvenation (20-30 J/cm(2)) produces high amounts of ROS, which destroy old collagen fibers, encouraging the formation of new ones. On the other hand, at inner depths of the skin, where the light intensity is much weaker, low amounts of ROS are formed, which are well known to stimulate fibroblast proliferation.

Influence of Visible Light and Ultraviolet Irradiation on Motility and Fertility of Mammalian and Fish Sperm

OBJECTIVE

The effects of visible light irradiation on sperm motility, fertility, and reactive oxygen species (ROS) formation were investigated and compared in ram and fish (tilapia).

BACKGROUND DATA

Low-energy visible light has previously been found to modulate various processes in different biological systems. In the literature, it is accepted that the first step following visible light irradiation is the formation of ROS by endogenous cellular photosensitizers.

METHODS

Sperm of ram and tilapia were irradiated with various light sources (400-800 nm white light, 660 nm red light, 360 nm blue light, 294 nm UV), and their motility and fertility rates were measured. The amount of ROS generated by irradiation was estimated using electron paramagnetic resonance (EPR) technique.

RESULTS

Sperm taken from tilapia showed higher motility and fertility following red and white light irradiation. In contrast, the motility and fertility of ram sperm were slightly increased only by red light. A negative effect on motility and fertility of sperm of both species was obtained following irradiation with UV and blue light. The amount of ROS produced in irradiated tilapia sperm was much higher than that of ram sperm.

CONCLUSIONS

The results show that different wavelengths differentially affect tilapia and ram sperm motility and fertilization. The difference in response to the various light sources might be explained by the different amounts of ROS formation by ram and tilapia, which are in agreement with the physiology of fertilization appropriate to each of these species. Based on these results, it is suggested that in vitro fertilization in mammals should be performed in darkness or at least under red light.

ESR detection of 1O2 reveals enhanced redox activity in illuminated cell cultures

Low-energy visible light (LEVL) has previously been found to modulate various processes in different biological systems. One explanation for the stimulatory effect of LEVL is light-induced reactive oxygen species formation. In the present study, both sperm and skin cells were illuminated with LEVL and were found to generate singlet oxygen (1O2). The detection of 1O2 was performed using a trapping probe, 2,2,6,6-tetramethyl-4-piperidone, coupled with electron paramagnetic resonance spectroscopy. In addition, we have shown that, together with O2 generation, LEVL illumination increases the reductive capacity of the cells, which explains the difficulties encountered in 1O2 detection. The potential of visible light to change the cellular redox state may explain the recently observed biostimulative effects exerted by LEVL.

Daylight exposure and the other predictors of burnout among nurses in a University Hospital

The purpose of the study was to investigate if daylight exposure in work setting could be placed among the predictors of job burnout. The sample was composed of 141 nurses who work in Akdeniz University Hospital in Antalya, Turkey. All participants were asked to complete a personal data collection form, the Maslach Burnout Inventory, the Work Related Strain Inventory and the Work Satisfaction Questionnaire to collect data about their burnout, work-related stress (WRS) and job satisfaction (JS) levels in addition to personal characteristics. Descriptive statistics, parametric and non-parametric tests and correlation analysis were used in statistical analyses. Daylight exposure showed no direct effect on burnout but it was indirectly effective via WRS and JS. Exposure to daylight at least 3h a day was found to cause less stress and higher satisfaction at work. Suffering from sleep disorders, younger age, job-related health problems and educational level were found to have total or partial direct effects on burnout. Night shifts may lead to burnout via work related strain and working in inpatient services and dissatisfaction with annual income may be effective via job dissatisfaction. This study confirmed some established predictors of burnout and provided data on an unexplored area. Daylight exposure may be effective on job burnout.

Low-energy laser irradiation promotes cellular redox activity

Low-energy visible light (LEVL) has been shown to stimulate cell functions. This is called "photobiostimulation" and has been used successfully over the last three decades for treating a range of conditions, including soft tissue injuries, severe wounds, chronic pain, and more. Nevertheless, the mechanism of photobiostimulative processes is still being debated. It is obvious that, in order to interact with the living cell, light has to be absorbed by intracellular chromophores. In a search for chromophores responsible for photobiostimulation, endogenous porphyrins, mitochondrial and membranal cytochromes, and flavoproteins were found to be suitable candidates. The above-mentioned chromophores are photosensitizers that generate reactive oxygen species (ROS) following irradiation. As the cellular redox state has a key role in maintaining the viability of the cell, changes in ROS may play a significant role in cell activation. In the present review, we summarize evidence demonstrating that various ROS and antioxidants are produced following LEVL illumination. We found that very little evidence for NO formation in illuminated non-vascular smooth muscle cells exists in the literature. We suggest that the change in the cellular redox state which plays a pivotal role in maintaining cellular activities leads to photobiostimulative processes.

The efficacy of low-power lasers in tissue repair and pain control: a meta-analysis study

OBJECTIVE

We used statistical meta-analysis to determine the overall treatment effects of laser phototherapy on tissue repair and pain relief.

BACKGROUND DATA

Low-power laser devices were first used as a form of therapy more than 30 years ago. However, their efficacy in reducing pain or promoting tissue repair remains questionable.

METHODS

Following a literature search, studies meeting our inclusion criteria were identified and coded. Then, the effect size of laser treatment, that is, Cohen's d, was calculated from each study using standard meta-analysis procedures.

RESULTS

Thirty-four peer-reviewed papers on tissue repair met our inclusion criteria and were used to calculate 46 treatment effect sizes. Nine peer-reviewed papers on pain control met the inclusion criteria and were used to calculate nine effect sizes. Meta-analysis revealed a positive effect of laser phototherapy on tissue repair (d = +1.81; n = 46) and pain control (d = +1.11; n = 9). The positive effect of treatment on specific indices of tissue repair was evident in the treatment effect sizes determined as follows: collagen formation (d = +2.78), rate of healing (d = +1.57), tensile strength (d = +2.13), time needed for wound closure (d = +0.76), tensile stress (d = +2.65), number and rate of degranulation of mast cells (d = +1.87), and flap survival (d = +1.95). Further, analysis revealed the positive effects of various wavelengths of laser light on tissue repair, with 632.8 nm having the highest treatment effect (d = +2.44) and 780 nm the least (d = 0.60). The overall treatment effect for pain control was positive as well (d = +1.11). The fail-safe number-that is, the number of studies in which laser phototherapy has negative or no effect-needed to nullify the overall outcome of this analysis was 370 for tissue repair and 41 for pain control.

CONCLUSIONS

These findings mandate the conclusion that laser phototherapy is a highly effective therapeutic armamentarium for tissue repair and pain relief.

The efficacy of laser therapy in wound repair: a meta-analysis of the literature

OBJECTIVE

We determined the overall effects of laser therapy on tissue healing by aggregating the literature and subjecting studies meeting the inclusion and exclusion criteria to statistical meta-analysis.

BACKGROUND DATA

Low-level laser therapy (LLLT) devices have been in use since the mid sixties, but their therapeutic value remains doubtful, as the literature seems replete with conflicting findings.

MATERIALS AND METHODS

Pertinent original research papers were gathered from library sources, online databases and secondary sources. The papers were screened and coded; those meeting every inclusion and exclusion criterion were subjected to meta-analysis, using Cohen's d. statistic to determine the treatment effect size of each study.

RESULTS

Twenty-four studies with 31 effect sizes met the stringent inclusion and exclusion criteria. The overall mean effect of laser therapy on wound healing was highly significant (d = +2.22). Sub-analyses of the data revealed significant positive effects on wound healing in animal experiments (d = +1.97) as well as human clinical studies (d = +0.54). The analysis further revealed significant positive effects on specific indices of healing, for example, acceleration of inflammation (d = +4.45); augmentation of collagen synthesis (d = +1.80); increased tensile strength (d = +2.37), reduced healing time (d = +3.24); and diminution of wound size (d = +0.55). The Fail-Safe number associated with the overall effect of laser therapy was 509; a high number representing the number of additional studies-in which laser therapy has negative or no effect on wound healing-required to negate the overall large effect size of +2.22. The corresponding Fail-Safe number for clinical studies was 22.

CONCLUSION

We conclude that laser therapy is an effective tool for promoting wound repair.

Low energy visible light induces reactive oxygen species generation and stimulates an increase of intracellular calcium concentration in cardiac cells

Low energy visible light (LEVL) irradiation has been shown to exert some beneficial effects on various cell cultures. For example, it increases the fertilizing capability of sperm cells, promotes cell proliferation, induces sprouting of neurons, and more. To learn about the mechanism of photobiostimulation, we studied the relationship between increased intracellular calcium ([Ca2+]i) and reactive oxygen species production following LEVL illumination of cardiomyocytes. We found that visible light causes the production of O2. and H2O2 and that exogenously added H2O2 (12 microm) can mimic the effect of LEVL (3.6 J/cm2) to induce a slow and transient increase in [Ca2+]i. This [Ca2+]i elevation can be reduced by verapamil, a voltage-dependent calcium channel inhibitor. The kinetics of [Ca2+]i elevation and morphologic damage following light or addition of H2O2 were found to be dose-dependent. For example, LEVL, 3.6 J/cm2, which induced a transient increase in [Ca2+]i, did not cause any cell damage, whereas visible light at 12 J/cm2 induced a linear increase in [Ca2+]i and damaged the cells. The linear increase in [Ca2+]i resulting from high energy doses of light could be attenuated into a non-linear small rise in [Ca2+]i by the presence of extracellular catalase during illumination. We suggest that the different kinetics of [Ca2+]i elevation following various light irradiation or H2O2 treatment represents correspondingly different adaptation levels to oxidative stress. The adaptive response of the cells to LEVL represented by the transient increase in [Ca2+]i can explain LEVL beneficial effects.