Light-emitting Diode Irradiation Research Articles

Eco-friendly LEDs radiation-assisted photocatalytic mineralization of toxic azure B dye using Bi2MoZnO7 nanocomposite

The present time nanocomposites show highly improved photocatalytic performance in water pollution remediation technology. Herein, BMZ (Bi2MoZnO7) nanocomposite photocatalyst has been synthesized via the co-precipitation method. The structural and morphological studies were interpreted by analytical techniques including X-Ray Diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), and Energy Dispersive X-ray (EDX) analyses. The accomplishment of photocatalysis was determined by the mineralization of toxic azure B dye using a light-emitting diode (LED) as a source of radiation. The characterization studies revealed that the average particle size of BMZ nanocomposite was 28 nm with a flake-like structure having a smooth surface. An EDX spectrum shows the characteristic peaks of Bi, Mo, Zn, and O elements. The parameters such as pH, dye concentration, catalyst weight, reusability of photocatalyst, Fenton’s reagent, CO2, COD, NO3− and SO42− evaluation, and N2 and O2 purging were studied for optimum conditions. Fenton’s reagent test is one of the green approaches in which OH is generated that is utilized for the degradation of toxic azure B dye. The photocatalytic degradation in Fe2+/H2O2/BMZ/Azure B system, high value of the rate constant was recorded as compared to the experiments, performed without BMZ nanocomposite photocatalyst. The eco-friendly LEDs irradiation was applied as a light source material throughout the experiment. The 98 % degradation of toxic azure B dye was observed in 120 min with the highest rate constant (k = 6.1 × 10−4 s−1) in LEDs irradiation.

Photo‐induced organo‐manganese‐mediated radical polymerization of acrylates under LED irradiation

The role of manganese in photo‐induced organometallic‐mediated radical polymerization (photo‐OMRP) under LED (light‐emitting diode) irradiation has not been previously explored. In this study, four manganese (II) complexes, namely [Mn(6‐tert‐butyl‐N,N′‐propanebis [salicylimine])] (Mn‐Bu), [Mn(6,3‐di‐tert‐butyl‐N,N′‐propanebis [salicylimine])] (Mn‐Bu2), [Mn(6‐ethoxy‐N,N′‐propanebis [salicylimine])] (Mn‐Ethoxy), and [Mn(6,3‐di‐ethoxy‐N,N′‐propanebis [salicylimine])] (Mn‐Ethoxy2), were synthesized using both symmetrical and non‐symmetrical tetradentate N2O2 Schiff base ligands. The Schiff base ligands were characterized by Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–Vis), and nuclear magnetic resonance spectroscopy (NMR). The Mn (II) complexes were characterized by FTIR, UV–Vis, elemental analysis, molar conductivity, cyclic voltammetry, MALDI‐TOF mass spectrometry, electron paramagnetic resonance, and rationalized with density functional theory (DFT) studies. All complexes were evaluated as photo‐OMRP mediators under LED irradiation at 390 nm and in the 400–800 nm range. The photopolymerization utilized methyl acrylate (MA) and diphenyl(2,4,6‐trimethylbenzoyl)phosphine oxide (TPO) in varying molar ratios of [MA]/[MnII]/[TPO] (900/1/1, 600/1/1, and 600/1/0.5). The photo‐OMRP of MA mediated by Mn‐Bu2 showed the best control over molecular weight (Mn matching Mn,th) and dispersity (Ð < 1.30) at a [MA]/[MnII]/[TPO] = 600/1/0.5 M ratio. The polymerization system demonstrated a living character, as evidenced by reversible “on/off” light source switching. Furthermore, a block copolymer of poly (methyl acrylate)‐b‐poly (butyl acrylate) was successfully synthesized employing a sequential visible‐light‐induced process, with the Mn‐Bu2 system showing the best results.

Analysis of Volatile Aroma Components in Different Parts of Shiitake Mushroom (Lentinus edodes) Treated with Ultraviolet C Light-Emitting Diodes Based on Gas Chromatography-Ion Mobility Spectroscopy.

Further assessment of ultraviolet C light-emitting diode (UVC-LED) irradiation for influencing shiitake mushrooms' (Lentinus edodes) volatile and sensory properties is needed. In this study, a comparison of UVC-LED irradiation treatment on the flavor profiles in various parts of shiitake mushrooms was conducted using gas chromatography-ion mobility spectrometry (GC-IMS) and sensory analysis. Sixty-three volatile compounds were identified in shiitake mushrooms. The fresh shiitake mushrooms were characterized by the highest values of raw mushroom odors. After UVC-LED treatment, the content of C8 alcohols decreased, especially that of 1-octen-3-ol, while the content of aldehydes increased, especially the content of nonanal and decanal. The score of fatty and green odors was enhanced. For fresh samples, the mushroom odors decreased and the mushroom-like odors weakened more sharply when treated in ethanol suspension than when treated with direct irradiation. The fruit odors were enhanced using direct UVC-LED irradiation for fresh mushroom samples and the onion flavor decreased. As for shiitake mushroom powder in ethanol suspension treated with UVC-LED, the sweaty and almond odor scores decreased and the vitamin D2 content in mushroom caps and stems reached 668.79 μg/g (dw) and 399.45 μg/g (dw), respectively. The results obtained from this study demonstrate that UVC-LED treatment produced rich-flavored, quality mushroom products.

Continuous microalgal culture module and method of culturing microalgae containing macular pigment

This study established and investigated continuous macular pigment (MP) production with a lutein (L):zeaxanthin (Z) ratio of 4–5:1 by an MP-rich Chlorella sp. CN6 mutant strain in a continuous microalgal culture module. Chlorella sp. CN6 was cultured in a four-stage module for 10 days. The microalgal culture volume increased to 200 L in the first stage (6 days). Biomass productivity increased to 0.931 g/L/day with continuous indoor white light irradiation during the second stage (3 days). MP content effectively increased to 8.29 mg/g upon continuous, indoor white light and blue light-emitting diode irradiation in the third stage (1 day), and the microalgal biomass and MP concentrations were 8.88 g/L and 73.6 mg/L in the fourth stage, respectively. Using a two-step MP extraction process, 80 % of the MP was recovered with a high purity of 93 %, and its L:Z ratio was 4–5:1.

Rare-Earth Metal-Organic Framework with Nonplanar Porphyrin Groups for High-Efficiency Photocatalysis.

Nonplanar porphyrins play crucial roles in many biological processes and chemical reactions as catalysts. However, the preparation of artificial nonplanar porphyrins suffers from complicated organic syntheses. Herein, we present a new rare-earth porphyrinic metal-organic framework (RE-PMOF), BUT-233, which is a three-dimensional (3D) framework structure with the flu topology consisting of 4-connected BBCPPP-Ph ligands H4BBCPPP-Ph = 5',5⁗-(10,20-diphenylporphyrin-5,15-diyl)bis([1,1':3',1″-terphenyl]-4,4'' dicarboxylic acid) and 8-connected Eu6 clusters. Noteworthily, the porphyrin cores of the BBCPPP-Ph ligands in BUT-233 are nonplanar with a ruffle-like conformation. In contrast, the porphyrin core in the free ligand H4BBCPPP-Ph is in a nearly ideally planar conformation, as confirmed by its single-crystal structure. BUT-233 is microporous with 6-8 Å pores and a Brunauer-Emmett-Teller (BET) surface area of 649 m2/g, as well as high stability in common solvents. The MOF was used as a photocatalyst for the oxidation degradation of a chemical warfare agent model molecule CEES (CEES = 2-chloroethyl ethyl sulfide) under the light-emitting diode (LED) irradiation and an O2 atmosphere at room temperature. CEES was almost completely converted into its nontoxic light-oxidized product CEESO (CEESO = 2-chloroethyl ethyl sulfoxide) in only 5 min with t1/2 = 2 min (t1/2: half-life). Moreover, the toxic deep-oxidized product 2-chloroethyl ethyl sulfone (CEESO2) was not detected. The catalytic activity of BUT-233 was high in comparison with those of some previously reported MOF catalysts. The results of photo/electrochemical property studies suggested that the high catalytic activity of BUT-233 was benefited from the presence of nonplanar porphyrin rings on its pore surface.

Effect of Low-Level Diode Laser and Red Light-Emitting Diode on Survival and Osteogenic/Odontogenic Differentiation of Human Dental Pulp Stem Cells.

Background: This investigation set out to compare the impacts of low-level diode laser (LLDL) and red light-emitting diode (LED) on the survival of human dental pulp stem cells (hDPSCs) and osteogenic/odontogenic differentiation. Methods and materials: In this ex vivo experimental study, the experimental groups underwent the irradiation of LLDL (4 J/cm2 energy density) and red LED in the osteogenic medium. Survival of hDPSCs was assessed after 24 and 48 h (n = 9) using the methyl thiazolyl tetrazolium (MTT) assay. The assessment of osteogenic/odontogenic differentiation was conducted using alizarin red staining (ARS; three repetitions). The investigation of osteogenic and odontogenic gene expression was performed at two time points, specifically 24 and 48 h (n = 12). This analysis was performed utilizing real-time reverse-transcription polymerase chain reaction (RT-PCR). The groups were compared at each time point using SPSS version 24. To analyze the data, the Mann-Whitney U test, analysis of variance, Tukey's test, and t-test were utilized. Results: The MTT assay showed that LLDL significantly decreased the survival of hDPSCs after 48 h, compared with other groups (p < 0.05). The qualitative results of ARS revealed that LLDL and red LED increased the osteogenic differentiation of hDPSCs. LLDL and red LED both upregulated the expression of osteogenic/odontogenic genes, including bone sialoprotein (BSP), alkaline phosphatase (ALP), dentin matrix protein 1 (DMP1), and dentin sialophosphoprotein (DSPP), in hDPSCs. The LLDL group exhibited a higher level of gene upregulation (p < 0.0001). Conclusions: The cell survival of hDPSCs was reduced, despite an increase in osteogenic/odontogenic activity. Clinical relevance: Introduction of noninvasive methods in regenerative endodontic treatments.

Assessing the Efficacy of UV-C Light for the Inactivation of Phytopythium and Phytophthora Species in Water: A Mathematical Modeling Approach Using an Ultraviolet Light-Emitting-Diode System

The use of untreated, recirculated irrigation water is a profitable practice, but it can harbor plant pathogens such as Phytophthora ( Pt) cinnamomi, Pt. nicotianae, Phytopythium ( Pp) vexans, and Pp. helicoides, posing disease risks in crop production. UV-C (240 to 290 nm) light-emitting diode (LED) irradiation was evaluated for inactivating the zoospores of oomycetes in water, providing potential for effective treatment. Zoospore suspensions were exposed to quantifiable UV-C doses under dynamic stirring, calculated by multiplying fluence rate (mW cm−2) and exposure time(s). UV-C irradiation effectively inactivated the tested pathogens following linear (logarithmic linear [ Pt. cinnamomi and Pt. nicotianae]) and nonlinear (Weibull and Weibull + tail [ Pp. vexans and Pp. helicoides]) kinetics as identified by parameters of goodness of model fit: high R2 and low root mean square error (RMSE) values. D10 values of Pt. cinnamomi and Pt. nicotianae calculated from the rate constants ( Kmax) of the log-linear models were 5.05 ± 0.38 mJ cm−2 ( R2 = 0.95, RMSE = 0.091, Kmax = 0.49 ± 0.03) and 4.73 ± 0.33 mJ cm−2 ( R2 = 0.96, RMSE = 0.091, Kmax = 0.49 ± 0.03), respectively. The Weibull + tail model best described the inactivation of Pp. vexans ( R2 = 0.97, RMSE = 0.099) and Pp. helicoides ( R2 = 0.96, RMSE = 0.083), and the δ and Nres values were determined to be 9.88 ± 0.12 and 2.06 ± 0.06 and 11.47 ± 0.38 and 2.45 ± 0.05, respectively. These study findings can be applied to develop water disinfection systems, either alone or in combination with other methods, for effective control of pathogens in irrigation systems. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Light emitting diode (LED) irradiation of liposomes enhances drug encapsulation and delivery for improved cancer eradication

Liposomes are widely used as drug delivery nanoplatforms because of their versatility and biocompatibility; however, their ability to load certain drugs may be suboptimal. In this study, we generated liposomes using a combination of DSPE and DSPE-PEG-2 k lipids and loaded them with doxorubicin (DOX) and paclitaxel (PTX), to investigate the effects of light emitting diode (LED) irradiation on liposome structure and drug loading efficiency. Scanning and transmission electron microscopy revealed that the surface of liposomes irradiated with blue or near-infrared LEDs (LsLipo) was rougher and more irregular than that of non-LED-irradiated liposomes (NsLipo). Nuclear magnetic resonance analysis showed that the hydrogen peak originating from the lipid head groups was lower in LsLipo than in NsLipo preparations, indicating that LED irradiation changed the chemical and physical properties of the liposome. Structural changes, such as reduced rigidity, induced by LED irradiation, increased the loading efficiency of DOX and PTX. In vitro and in vivo experiments showed that LsLipo were more effective at inhibiting the growth of cancer cells than NsLipo. Our findings suggest that LED irradiation enhances the drug delivery efficacy of liposomes and offer new possibilities for improving drug delivery systems.

Enhancement of riboflavin-mediated photodynamic inactivation against Salmonella on tuna fillets coupled with slightly basic electrolyzed water

This study aimed to develop an efficient PDI system to kill Salmonella in solution or on tuna fillets under 455 nm blue light-emitting diodes (LED) irradiation, by selecting slightly basic electrolyzed water (SBEW) as the solvent. Results showed that the solvent of SBEW increased the solubility of riboflavin, and notably strengthened the production of ROS compared to normal saline solution. On this basis, the riboflavin-mediated PDI coupled with SBEW enhanced the inactivation of Salmonella, supported by that the viability of Salmonella was significantly (P < 0.05) inactivated by 5.02 Log10 CFU/mL with 9.36 J/cm2 irradiation and 80 μM riboflavin, and no viable cells were detected when the irradiation dose was increased to 12.48 J/cm2. The action mechanisms showed that this novel PDI damaged the cell membrane causing the leakage of cellular contents, degraded the genomic DNA and enhanced the lipid peroxidation in Salmonella. In addition, the PDI system efficiently killed >4.0 Log10 CFU/g of Salmonella on tuna fillets with 120 μM riboflavin and 18.72 J/cm2 irradiation. Furthermore, the PDI system decelerated the proliferation of Salmonella, the changes of electrical conductivity, pH and color, and lipid oxidation in tuna fillets during the storage. This study provides a promising PDI system to control food pathogen contamination and preserve the storage quality of seafood.

(276) Light Emitting Diodes (LED) as a Potential Therapy for Erectile Function: A Preclinical Study in a Cavernous Nerve Injury Model

Abstract Introduction Erectile dysfunction (ED) induced by nerve injury including prostatectomy poorly responds to PDE5 inhibitor and requires invasive treatment. Light emitting diodes (LED) in some spectral range, is able to irradiate cells without overheating for its low energy consumption and to enhance mitochondrial metabolism, intracellular energy transfer, and thereby cell proliferation and tissue regeneration in some organs. We, herein, investigated whether and how LED therapy may improve penile erection in mouse cavernous nerve injury (CNI) - induced ED model Objective To identify the optimal LED parameters using molecular, histological, and erectile function analysis in cavernous nerve injury. Methods Eight week old male mice (n=120) were divided into 5 age-matched groups, a sham operation group receiving heat treatment, a CNI group receiving heat treatment, a CNI group receiving red light of LED (wavelength; 660 ±3% nm), a CNI group receiving near infrared light of LED (wavelength; 830 ±2% nm), and a CNI group receiving combination of both LED light. Mice were exposed to LED light for 30 minutes on the ventral side including penis for 5 consecutive days after CNI operation. Molecular study, histopathological analysis of the penis and erectile function test were done 2 weeks following the treatment in each subject. Results CNI group with heat treatment had much lower maximum and total ICP than sham control group. In contrast, three groups with LED light irradiation exhibited considerably improved maximum and total ICP, and the group with both LED treatments had the best erectile performance, reaching 90% of the sham surgery group. Histologically, mice treated with RED, NIR, or LED irradiation had more cavernous pericytes and endothelial cells than CNI mice after sham operation. In addition, all three CNI groups with various LED lengths improved neuroprotection and brain regeneration in CNI mice. All groups treated with LED showed increased expression of βIII-tubulin, neurofilament-1, and nNOS in cavernous tissue and dorsal nerve bundle. Additionally, LED treatment in three groups, particularly the combination group, significantly increased βIII-tubulin, S100, and myelin basic protein levels, indicating axonal integrity or expansion in the dorsal root and major pelvic ganglions. Molecular analysis of downstream signals of neural regeneration or angiogenesis showed that 3 groups with LED treatment increased phosphorylated PI3K, neurotrophic factors like BDNF, NGF, and NT-3, and angiogenic factors like angiopoietin1 and vascular endothelial growth factor in cavernous tissue and llpopolysaccharide-treated PC-12 cells. The TUNEL assay and BrdU staining of these tissue and cells showed lower cell apotosis and proliferation in LED-treated groups. Conclusions The results show that LED therapy with RED, NIR, preferably combination of each wavelength improves penile erection by neural progection or regeneration in cavernous nerve injury induced-ED. This noninvasive therapy may be useful in near future for ED refractory to PDE5 inhibitor. As far as we are aware, this is the first research to demonstrate the advantage of LED therapy, low level in sexual dyfunction field. Disclosure No.

Antimicrobial photodynamic effect of the photosensitizer riboflavin, alone and in combination with colistin, against pandrug-resistant Pseudomonas aeruginosa clinical isolates

IntroductionDevelopment of multi-, extensively-, and pandrug-resistant (MDR, XDR, and PDR) strains of Pseudomonas aeruginosa remains a major problem in medical care. The present study evaluated the effect of antimicrobial photodynamic therapy (aPDT) as a monotherapy and in combination with colistin against P. aeruginosa isolates. MethodsTwo P. aeruginosa isolates recovered from patients with respiratory tract infections were examined in this study. Minimum inhibitory concentration (MIC) of colistin was determined by the colistin broth disk elution (CBDE) and the reference broth microdilution (rBMD) methods. aPDT was performed using the photosensitizer (Ps) riboflavin at several concentrations and a light-emitting diode (LED) emitting blue light for different irradiation times with or without colistin at 1/2 × MIC concentration. ResultsBoth PA1 and PA2 isolates were identified as colistin-resistant P. aeruginosa with a MIC ≥4 μg/mL by the CBDE and MICs of 512 μg/mL and 256 μg/mL, respectively, by the rBMD. In aPDT, neither riboflavin nor LED light alone had antibacterial effects. The values of colony forming units per milliliter (CFU/mL) in both isolates were significantly reduced by LED + Ps treatments in a time-dependent manner (LED irradiation time) and dose-dependent manner (Ps concentration). In comparison with control, treatment with Ps (50 μM) + LED (120 s) and Ps (100 μM) + LED (120 s) resulted in 0.27 log10 CFU/mL and 0.43 log10 CFU/mL reductions in PA1, and 0.28 log10 CFU/mL and 0.34 log10 CFU/mL reductions in PA2, respectively, (P < 0.01). The best results were obtained after the combination of aPDT followed by colistin, which increased bacterial reduction, resulting in a 0.41−0.7 log10 CFU/mL reduction for PA1 and 0.35−0.83 log10 CFU/mL reduction for PA2 (P = 0.001). Conclusions: This study suggests the potential implications of aPDT in combination with antibiotics, such as colistin for treatment of difficult-to-treat P. aeruginosa infections.

Efficacy and Safety of High Density LED Irradiation Therapy for Patients With Hand Osteoarthritis: A Single-Center Clinical Study.

To assess the safety and effectiveness of high-density light-emitting diode (LED) irradiation therapy in patients with hand osteoarthritis (OA) and compare the pre- and post-intervention symptoms. Twenty-three patients with hand OA underwent eight sessions of high-density LED irradiation therapy directed at the five most painful areas in the finger joints. Each session lasted for 18 minutes; and the sessions were conducted twice a week, for 4 weeks. We evaluated the degree of pain using the visual analogue scale, ring size, and passive range of motion (flexion+extension) for two most painful joints from the baseline to post-therapy (weeks 4 and 6). High-density LED irradiation therapy significantly reduced the pain posttreatment compared with that observed at the baseline (p<0.001). Although improvements were observed in ring size and joint range of motion at 4 and 6 weeks, they were not statistically significant (p>0.05). No adverse events were observed. We examined the safety and effectiveness of high-density LED irradiation therapy in reducing pain and hand swelling and improving joint mobility in patients with hand OA. These results suggest that high-density LED irradiation therapy has the potential to be an important strategy for managing hand OA.

Effect of magnesium oxide nanoparticles and LED irradiation on the viability and differentiation of human stem cells of the apical papilla.

Currently, regenerative endodontic treatments are gaining more and more attention, and stem cells play a significant role in these treatments. In order to enhance stem cell proliferation and differentiation, a variety of methods and materials have been used. The purpose of this study was to determine the effects of magnesium oxide nanoparticles and LED irradiation on the survival and differentiation of human stem cells from apical papilla. The MTT test was used to measure the cell survival of SCAPs that had been exposed to different concentrations of magnesium oxide nanoparticles after 24 and 48h, and the concentration with the highest cell survival rate was picked for further studies. The cells were classified into four distinct groups based on their treatment: (1) control, which received no exposure, (2) exposure to magnesium oxide nanoparticles, (3) exposure to light emitting diode (LED) irradiation (635nm, 200mW/cm2) for 30s, (4) exposure simultaneously with magnesium oxide nanoparticles and LED irradiation. A green approach was employed to synthesize magnesium oxide nanoparticles. Quantitative real time PCR was used to measure the gene expression of osteo/odontogenic markers such as BSP, DSPP, ALP and DMP1 in all four groups after treatment, and Alizarin red S staining (ARS) was used to determine the osteogenic differentiation of SCAPs by demonstrating the Matrix mineralization. The highest viability of SCAPs was observed after 24h in concentration 1 and 10µg/mL and after 48h in concentration 1µg/mL, which were not significantly different from the control group. In both times, the survival of SCAPs decreased with increasing concentration of magnesium oxide nanoparticles (MgONPs). According to the results of Real-time PCR, after 24 and 48h, the highest differentiation of BSP, DMP1, ALP and DSPP genes was observed in the LED + MgONPs group, followed by MgONPs and then LED, and in all 3 experimental groups, it was significantly higher than control group (P < 0.05). Also, after 24 and 48h, the density of ARS increased in all groups compared to the control group, and the highest density was observed in the MgONPs + LED and MgONPs groups. This research concluded that exposure to SCAPs, MgONPs, and LED irradiation has a significant effect on enhancing gene expression of odontogenic/osteogenic markers and increasing matrix mineralization.

Photobiomodulation with 630-nm LED Inhibits M1 Macrophage Polarization via STAT1 Pathway Against Sepsis-Induced Acute Lung Injury.

Background: Sepsis-induced acute lung injury (ALI) is a clinical syndrome characterized by excessive uncontrolled inflammation. Photobiomodulation such as light-emitting diode (LED) irradiation has been used to attenuate inflammatory disease. Objective: The protective effect of 630 nm LED irradiation on sepsis-induced ALI remains unknown. The purpose of this study was to investigate the role of 630 nm LED irradiation in sepsis-induced ALI and its underlying mechanism. Methods and results: C57BL/6 mice were performed cecal ligation and puncture (CLP) for 12 h to generate experimental sepsis models. Histopathology analysis showed that alveolar injury, inflammatory cells infiltration, and hemorrhage were suppressed in CLP mice after 630 nm LED irradiation. The ratio of wet/dry weigh of lung tissue was significantly inhibited by irradiation. The number of leukocytes was reduced in bronchoalveolar lavage fluid. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) results and enzyme-linked immunosorbent assay showed that 630 nm LED irradiation significantly inhibited the mRNA and protein levels of M1 macrophage-related genes in the lung of CLP-induced septic mice. Meanwhile, LED irradiation significantly inhibited signal transducer and activator of transcription 1 (STAT1) phosphorylation in the lung of septic mice. In vitro experiments showed that 630 nm LED irradiation significantly inhibited M1 genes mRNA and protein expression in THP-1-derived M1 macrophages without affecting the cell viability. LED irradiation also significantly inhibited the level of STAT1 phosphorylation in THP-1-derived M1 macrophages. Conclusions: We concluded that 630 nm LED is promising as a treatment against ALI through inhibiting M1 macrophage polarization, which is associated with the downregulation of STAT1 phosphorylation.

Near-Infrared Induced miR-34a Delivery from Nanoparticles in Esophageal Cancer Treatment.

Current nucleic acid delivery methods have not achieved efficient, non-toxic delivery of miRNAs with tumor-specific selectivity. In this study, a new delivery system based on light-inducible gold-silver-gold, core-shell-shell (CSS) nanoparticles is presented. This system delivers small nucleic acid therapeutics with precise spatiotemporal control, demonstrating the potential for achieving tumor-specific selectivity and efficient delivery of miRNA mimics. The light-inducible particles leverage the photothermal heating of metal nanoparticles due to the local surface plasmonic resonance for controlled chemical cleavage and release of the miRNA mimic payload. The CSS morphology and composition result in a plasmonic resonance within the near-infrared (NIR) region of the light spectrum. Through this method, exogenous miR-34a-5p mimics are effectively delivered to human squamous cell carcinoma TE10 cells, leading to apoptosis induction without adverse effects on untransformed keratinocytes in vitro. The CSS nanoparticle delivery system is tested in vivo in Foxn1nu athymic nude mice with bilateral human esophageal TE10 cancer cells xenografts. These experiments reveal that this CSS nanoparticle conjugates, when systemically administered, followed by 850nm light emitting diode irradiation at the tumor site, 6 h post-injection, produce a significant and sustained reduction in tumor volume, exceeding 87% in less than 72 h.

Effects of 625 nm light-emitting diode irradiation on preventing ER stress-induced apoptosis via GSK-3β phosphorylation in MC3T3-E1.

Prolonged endoplasmic reticulum (ER) stress contributes to cell apoptosis and interferes with bone homeostasis. Although photobiomodulation (PBM) might be used for ER stress-induced diseases, the role of PBM in relieving cell apoptosis remains unknown. During ER stress, glycogen synthase kinase-3β (GSK-3β) is critical; however, its functions in PBM remain uncertain. Thus, this study aimed to investigate the role of GSK-3β in 625 nm light-emitting diode irradiation (LEDI) relieving tunicamycin (TM)-induced apoptosis. Based on the results, pre-625 nm LEDI (Pre-IR) phosphorylated GSK-3β via ROS production. Compared with the TM group, Pre-IR + TM group reduced the phosphorylation of the α-subunit of eukaryotic translation initiation factor 2 (eIF-2α) and B-cell lymphoma protein 2 (Bcl-2)-associated X (Bax)/Bcl-2 ratio through regulating GSK-3β. Furthermore, a similar tendency was observed between Pre-IR + TM and Pre-LiCl+TM groups in preventing TM-induced early and late apoptosis. In summary, this study suggests that the Pre-IR treatment in TM-induced ER stress is beneficial for preventing cell apoptosis via GSK-3β phosphorylation.

Adjunctive effect of 470-nm and 630-nm light-emitting diode irradiation in experimental periodontitis treatment: a preclinical study.

This study investigated the adjunctive effect of light-emitting diodes (LEDs) in the treatment of experimental periodontitis. Experimental periodontitis was induced by placing ligatures around the mandibular second, third, and fourth premolars of 6 beagles for 3 months. After ligature removal, periodontitis progressed spontaneously for 2 months. The animals' hemimandibles were allocated among the following 3 groups: 1) no treatment (control), 2) scaling and root planing (SRP), and 3) SRP with LED irradiation at 470-nm and 630-nm wavelengths (SRP/LED). The probing pocket depth (PPD) and gingival recession (GR) were measured at baseline, 6 weeks, and 12 weeks. The clinical attachment level (CAL) was calculated. After 12 weeks, histological and histomorphometric assessments were performed. The distances from the gingival margin to the apical extent of the junctional epithelium (E) and to the connective tissue (CT) attachment were measured, as was the total length of soft tissue (ST). PPD and CAL increased at 12 weeks compared with baseline in the control group (6.31±0.43 mm to 6.93±0.50 mm, and 6.46±0.60 mm to 7.61±0.78 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP group (6.01±0.59 to 4.81±0.65 mm, and 6.51±0.98 to 5.39±0.93 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP/LED group (6.03±0.39 to 4.46±0.47 mm, and 6.11±0.47 to 4.78±0.57 mm, respectively). The E/ST and CT/ST ratios significantly differed among the 3 groups (P<0.05). The clinical parameters and histologic findings demonstrated that 470-nm and 630-nm wavelength LED irradiation accompanying SRP could improve treatment results. Within the study limitations, 470 nm and 630 nm wavelength LED irradiation might provide additional benefits for periodontitis treatment.

The Anti-Inflammatory Effect of Multi-Wavelength Light-Emitting Diode Irradiation Attenuates Dry Eye Symptoms in a Scopolamine-Induced Mouse Model of Dry Eye.

Dry eye disease is a common condition in patients of all ages, causing discomfort and potential visual problems. Current treatments, including artificial tears and anti-inflammatory drugs, have certain limitations, encouraging research into alternative therapies. We investigated the therapeutic potential of multi-wavelength light-emitting diode (LED) irradiation of mice with dry eye. First, we showed that multi-wavelength LED irradiation was non-toxic to human corneal epithelial cells and improved cell viability. We then used a scopolamine-induced mouse model of dry eye to assess the effects of multi-wavelength LED irradiation on various clinical parameters. This treatment increased the tear volume and reduced corneal irregularity, thus improving dry eye. Histological analysis revealed that multi-wavelength LED irradiation protected against corneal epithelial damage and the associated reduction in epithelial thickness and would thus improve the corneal health of dry eye patients. Multi-wavelength LED irradiation significantly reduced the corneal levels of pro-inflammatory cytokines IL-6, IL-1β, and TNF-α; the treatment was thus anti-inflammatory. Our results suggest that multi-wavelength LED irradiation may serve as a safe and effective treatment for dry eye, alleviating symptoms, reducing inflammation, and promoting corneal health.

Effects of green light-emitting diode irradiation on hepatic differentiation of hepatocyte-like cells generated from human adipose-derived mesenchymal cells

Light-emitting diode (LED) irradiation has been used in the differentiation of mesenchymal stem cells into a variety of cell types. This study investigated the effect of green LED (GLED) irradiation on the differentiation of adipocyte-derived mesenchymal cells into hepatocyte-like cells (HLCs) and the mechanism of its action. HLCs in the hepatocyte maturation phase were irradiated with GLED (520 nm, 21 W/m2, 5 min/day for 10 days). The cells were then assessed for expression of hepatocyte maturity genes and opsin 3 (OPN3), hepatocyte function, viability, apoptosis, and levels of reactive oxygen species (ROS), intracellular adenosine triphosphate (ATP) and calcium ions (Ca2+). GLED irradiation increased Alpha-1 antitrypsin and Ornithine transcarbamylase gene expression, promoted Cytochrome P450 3A4 activity and urea synthesis, and elevated intracellular ROS, ATP and Ca2+ levels. OPN3 expression was significantly more upregulated in GLED-irradiated HLCs than in the non-irradiated HLCs. No significant difference in cell viability or apoptosis was observed between GLED-irradiated and non-irradiated HLCs. GLED irradiation can promote hepatocyte maturation and functions through OPN3. GLED irradiation also stimulated mitochondrial function via Ca2+/ATP/ROS activation. GLED irradiation has potential to support cell-based transplantation in patients.

Pre-harvest supplemental LED treatments led to improved postharvest quality of sweet basil leaves.

This study determined the effects of supplemental light-emitting diode (LED) treatments on the nutrient quality and volatile compounds of sweet basil leaves during stimulated shelf-life. Basil plants were grown in a greenhouse under different supplemental LEDs (white, blue, red, or red + blue each at 100μmolm-2s-1), while plants grown under sunlight served as the control. The findings revealed that plant height and canopy of basil showed a significant increase under red LED irradiation, while the leaf area was improved by the blue LED exposure. Moreover, blue LEDs enhanced the levels of phenolic compounds, total phenolic contents, total flavonoid contents, and PAL (phenylalanine ammonia-lyase) activity in harvested sweet basil leaves. Additionally, red + blue LEDs lighting stimulated the production of volatile compounds. During storage, the samples treated with blue LEDs maintained a higher quality compared to the control samples. In conclusion, the application of blue or red + blue LEDs prior to harvest can be beneficial for promoting and preserving the nutritional quality of sweet basil.