Synergistic Effects of Light Therapy and Nutrition
Sunlight is a portion of the
electromagnetic radiation given off by the Sun
• Although cells in vitro are responsive to a variety of wavelengths in the electromagnetic spectrum, beneficial responses in vivo are observed within a narrow wavelength range.
• Lower wavelengths such as violet and ultraviolet penetrate less, whereas those in the red and infrared range have higher penetration.
• Energy at wavelengths shorter than 600nm are generally scattered in biological tissues in vivo and are absorbed by melanin, whereas water significantly absorbs energy at wavelengths higher than 1150nm.
• For clinical purposes = the in vivo therapeutic “optical window” strongly corresponds to red and near-infrared wavelengths. We will discuss further now how this is beneficial for peripheral neuropathy.
Low-Level-Laser (Light) Therapy (LLLT) For Peripheral Neuropathy
LLLT involves exposing cells or tissue to low levels of red and near infrared (NIR) light, and is referred to as “low level” because of its use of light at energy densities that are low compared to other forms of laser therapy that are used for ablation, cutting, and thermally coagulating tissue. LLLT is also known as “cold laser” therapy as the power densities used are lower
than those needed to produce heating of tissue. It was originally believed that LLLT or photobiomodulation required the use of coherent laser light, but more recently, light emitting diodes (LEDs) have been proposed as a cheaper alternative for peripheral neuropathy.
Light therapy For Peripheral Neuropathy – Is Science based!
Light Therapy has now developed into a therapeutic procedure that is sciencebased, well-substantiated, and utilized in three main ways:
1. To reduce inflammation, edema, and chronic joint disorders; especially peripheral neuropathy.
2. To promote healing of wounds, deeper tissues, and nerves.
3. To treat neurological disorders and pain conditions such as peripheral neuropathy.
Photochemical reaction= Biostimulation = Photobiomodulation
- A chromophoreis the part of a molecule responsible for its color.
- The color arises when a molecule absorbs certain wavelengths of visible lightand transmits or reflects others.
- Visible light that hits the chromophore can thus be absorbed by exciting an electron from its ground state into an excited state.
Chromophore within Mitochondria
= Initial Target of LLLT
Mitochondria are stimulated, leading to increased ATP production, modulation of reactive oxygen species, and induction of transcription factors.
Patient Benefits Include:
• Increased healing of chronic wounds
• Improvements in sports injuries and carpal tunnel syndrome
• Pain reduction in arthritis and neuropathies
• Amelioration of damage after heart attacks, stroke, and nerve injury
What does the research say?
“Photoneuromodulation of cytochrome oxidase activity is the most important primary mechanism of action of LLLT. Cytochrome oxidase is the primary photoacceptor of light in the red to near-infrared region of the
electromagnetic spectrum. It is also a key mitochondrial enzyme for
cellular bioenergetics, especially for nerve cells in the retina and the brain. Evidence shows that LLLT can secondarily enhance neural metabolism by regulating mitochondrial function, intraneuronal signaling systems, and redox states.”
Cytochrome c oxidase has been shown to have a new enzymatic activity—-the reduction of nitrite to nitric oxide. Low intensity light enhances nitric oxide synthesis by cytochrome c oxidase without altering its ability to reduce oxygen. From these findings, we propose that cytochrome c oxidase functions in photobiomodulation by producing nitric oxide, a signaling molecule which can then function in both intra- and extracellular signaling
“We show both in purified systems and in myocardium that R/NIR light can decay nitrosylhemes and release NO, and that this released NO may enhance the cardioprotective effects of nitrite. Thus, the photodissociation to NO and its synergistic effect with sodium nitrite may represent a noninvasive and site-specific means for increasing NO bioavailability.”
(1) NO via the beneficial cNOS pathway is decreased in joint structures exposed to chronic load-induced stresses and biochemical change-induced stresses,
(2) Monochromatic infrared light energy at an 890 nm wavelength, applied at the skin surface, is absorbed into blood vessels and stimulates production of NO in joints by the beneficial cNOS pathway,
(3) NO from the cNOS pathway may help decrease the detrimental effects of NO induced by iNOS and produced in OA pathology, and
(4) NO-based intervention may produce substantial pain relief without undesirable side effects by increasing circulation, decreasing nerve irritation, and decreasing inflammation in joints.
890nm (IR) causes the photo-dissociation of NO from hemoglobin in the red blood cells (and possibly from the endothelial cells as well) allowing NO to be free (locally) to do its work.
NO Release From Tissue or
- Significantly Improves circulation (via vasodilation)
- Reduces inflammation
- Decreases pain
- Increases angiogenesis – Builds new vessels
- Increases lymphatic activity- Decreases swelling
- Increases cell regeneration
(wound healing) – Stimulates tissue granulation & connective tissue
- Increases bone mineralization – Reduces osteoporosis
- Increases phagocytosis (immune response)
- Increases RNA-DNA synthesis
Certain vegetables possess a high nitrate content representing a potential source of vasoprotective nitric oxide via bioactivation which can ultimatley enhance results for peripheral neuropathy.
In healthy volunteers, approximately 3 hours after ingestion of a dietary nitrate load (beetroot juice 500 mL), BP was substantially reduced (max 10.4/8 mm Hg); an effect that correlated with peak increases in plasma
- Nitrite levels in cells treated with L-citrulline and GSH were significantly greater than control (p < 0.05).
- Plasma NOx with L-citrulline +GSH was significantly greater than control and L-citrulline (p < 0.05).
- Nitrite and NOx for Lcitrulline + GSH were significantly greater at 30 min post-exercise when compared to placebo (p < 0.05).
– McKinley S, Andrew T, Morita M, Willoughby D. Journal of the International Society of Sports Nutrition. 2015, 12:27
Conclusion: Combining L-citrulline with GSH augments increases in nitrite and NOx levels during in vitro and in vivo conditions. As a result patients with peripheral neuropathy often will see positive changes.
Symptomatic Reversal Of Peripheral Neuropathy in Patients with Diabetes
Forty-nine subjects with established diabetic peripheral neuropathy were
treated with monochromatic nearinfrared photo energy (MIRE) to
determine if there was an improvement of sensation. Loss of protective sensation characterized by Semmes-Weinstein monofilament values of 4.56 and above was present in 100% of subjects (range, 4.56 to 6.45), and 42 subjects (86%) had SemmesWeinstein values of 5.07 or higher.
The ability to discriminate between hot and cold sensation was absent (54%) or impaired (46%) in both groups prior to the initiation of MIRE treatment. 48 subjects (98%) exhibited improved sensation after 6 treatments, and all subjects had improved sensation after 12 treatments.
Therefore, MIRE may be a safe, drugfree, noninvasive treatment for the
consistent and predictable improvement of sensation in diabetic patients with peripheral neuropathy of the feet. (J Am Podiatr Med Assoc 92(3): 125-130, 2002)
Improvement of sensory impairment in Patients with Peripheral Neuropathy
27 patients with peripheral neuropathy received treatment with monochromatic near-infrared photoenergy (890 nm). Methods: All enrolled patients exhibited abnormal sensory perception (either hyperesthesia or hypoesthesia) based on a qualifying examination with the
Neurometer CPT (current perception threshold) (baseline CPT). The patients received 10 treatments (each lasting 40 minutes) during a 2-week period and then underwent CPT retesting to determine the extent of improvement of sensory impairment in myelinated and unmyelinated sensory fibers of the peroneal nerve.
Results: All patients obtained improvement in sensory impairment in comparison with baseline CPT measures, and 16 of the 27 patients achieved normal sensory responses in all nerve fiber subpopulations. Ten patients had been tested previously (initial CPT) and did not exhibit spontaneous improvement in sensory impairment during a mean period of 27 months before baseline CPT. After receiving the ATS treatments, however, this group of patients showed improvement in comparison with both initial CPT
results and baseline CPT. Conclusion: On the basis of the data from this study, the ATS seems to be a safe and effective treatment to improve sensory impairment associated with peripheral neuropathy due to diabetes and other causes. (Endocr Pract. 2004;10:24-30)