Table 1.
In vitro and preclinical studies on UVA, blue light and photobiomodulation (PBM), and nitric oxide (NO) bioavailability.
| Wavelength | Irradiance | Light source |
Model | Mechanisms / Outcome |
References |
|---|---|---|---|---|---|
| 320-420 nm | 34mW/cm2 | Mercury arc lamp | Human skin tissue | NOS-independent NO↑ Photo-decomposition of RSNO and nitrite |
[115] |
| 441.6 or 632.8 nm | ND | He-Cd (441.6 nm) and He-Ne (632.8 nm) lasers | HbNO solution | NO↑ Photodissociation of HbNO by He-Cd laser but not He-Ne laser |
[118] |
| 447, 532, 635 or 808 nm | 800 ± 17.9μW/cm2 | LD CW |
Cultured hTERT-RPE cells | Increase NOS-independent, but the substrate source of electrons entering the electron transport chain dependent NO generation Sequential or simultaneous exposures at two different wavelengths enhanced NO generation |
[114] |
| 590 ± 14 nm | up to 10W/m2 | LED CW |
Isolated mitochondria from yeast and mouse brain | Nitrite-dependent NO release by CCO↑ NO production increased in hypoxia 509-691 nm was stimulatory, but 820-880 nm was inhibitory in mouse brain mitochondria |
[123] |
| 632.5 nm | 0.26J/cm2 | CW He-Ne laser |
Cultured HUVECs | Increase NO generation via enhanced eNOS gene expression and eNOS phosphorylation at S1177 via Akt phosphorylation | [131] |
| 670nm | 170mW/cm2 for 5 min (51 J/cm2) | LED CW |
Mice | NO release from HbNO and MbNO Cardioprotection from ischemia and reperfusion injury in normal and diabetic mice, independent of NOS No effect of 740 and 830 nm was observed |
[126] |
| 670 nm | 5-50 mW/cm2 (1.5-15 J/cm2) | LED CW |
Cultured neonatal rat ventricular myocytes, cardiac muscle cell line HL-1 cells | NOS independent and dependent NO↑ Cellular ATP↑ Protect myocytes from hypoxia and reoxygenation-induced apoptosis |
[113] |
| 670nm | 60 mW/cm2 for 10 min (36 J) for 14 days | LED CW |
Mice, Rabbits, HUVECs | An increase in collateralization and blood flow in a hindlimb ischemia model in rabbits and mice HUVEC produced NO independently of NOS and increased proliferation and tube formation |
[125] |
| 670nm | 60 mW/cm2 for 3 min (11 J) | LED CW |
Rabbits | Increased NO release from HbNO or MbNO Reduction of nitrite to form NO in the anaerobic condition via the nitrite reductase activity of deoxyhemoglobin Cardioprotection in cardiac ischemia and reperfusion injury model in rabbits |
[124] |
| 670nm | 10 mW/cm2 for 5 min | LED CW |
Isolated facialis arteries of mice HMVEC-d |
Increased vasodilation of isolated arteries in an endothelium-dependent manner Induced NO release from the endothelium, suggestive from S-nitrosothiols or non-heme iron nitrosyl complexes |
[127] |
| 780nm | 300 J/cm2 10 consecutive days |
GaAlAs laser PW (300 Hz) |
Isolated femora from rats | NO↑ Stimulating bone healing of femora ex vivo |
[33] |
| 804nm | 8 mW/cm2 for 2 min (0.96 J/cm2) | GaAs laser CW | Rats | Increased iNOS expression and angiogenesis and decreased infarct size in a myocardial infarction model | [132] |
| 1064 and 1270nm | 10 mW/cm2 for 5 min | InGaAs laser CW |
HUVECs | NO↑ Enhancing HUVEC migration in vitro |
[80] |
UVA, ultraviolet-A; NO, nitric oxide; GaAs, Gallium-arsenide; Gallium-aluminum-arsenide, GaAlAs; RSNO, S-nitrosothiols; ND, Not described; He-Cd, helium-cadmium; He-Ne, heliumneon; HbNO, nitrosyl hemoglobin; LD, laser diode; CW, continuous wave; hTERT-RPE, human telomerase reverse transcriptase transformed retinal pigment epithelium; NOS, nitric oxide synthase; LED, light-emitting diode; CCO, Cytochrome c oxidase; HUVECs, human umbilical vein endothelial cell; HMVEC-d, Human dermal microvascular endothelial cells; eNOS, endothelial nitric oxide; MbNO, nitrosyl myoglobin; PW, pulse wave; iNOS, inducible nitric oxide.