Aging / Longevity

 2018 Sep;33(7):1513-1519. doi: 10.1007/s10103-018-2510-0. Epub 2018 Apr 26.

Photobiomodulation effects on mRNA levels from genomic and chromosome stabilization genes in injured muscle.

Author information

1
Laboratório de Pesquisa em Células Tronco, Departamento de Histologia e Embriologia, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, fundos, Vila Isabel, Rio de Janeiro, 20551-030, Brazil.
2
Laboratório de Biomorfologia e Patologia Experimental, Universidade Severino Sombra, Avenida Expedicionário Oswaldo de Almeida Ramos 280, Vassouras, Rio de Janeiro, 27700-000, Brazil.
3
Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, fundos, Vila Isabel, Rio de Janeiro, 20551-030, Brazil.
4
Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, fundos, Vila Isabel, Rio de Janeiro, 20551-030, Brazil. adnfonseca@yahoo.com.br.
5
Departamento de Ciências Fisiológicas, Instituto Biomédico, Universidade Federal do Estado do Rio de Janeiro, Rua Frei Caneca, 94, Rio de Janeiro, 20211-040, Brazil. adnfonseca@yahoo.com.br.

Abstract

Muscle injuries are the most prevalent type of injury in sports. A great number of athletes have relapsed in muscle injuries not being treated properly. Photobiomodulation therapy is an inexpensive and safe technique with many benefits in muscle injury treatment. However, little has been explored about the infrared laser effects on DNA and telomeres in muscle injuries. Thus, the aim of this study was to evaluate photobiomodulation effects on mRNA relative levels from genes related to telomere and genomic stabilization in injured muscle. Wistar male rats were randomly divided into six groups: control, laser 25 mW, laser 75 mW, injury, injury laser 25 mW, and injury laser 75 mW. Photobiomodulation was performed with 904 nm, 3 J/cm2 at 25 or 75 mW. Cryoinjury was induced by two applications of a metal probe cooled in liquid nitrogen directly on the tibialis anterior muscle. After euthanasia, skeletal muscle samples were withdrawn and total RNA extracted for evaluation of mRNA levels from genomic (ATM and p53) and chromosome stabilization (TRF1 and TRF2) genes by real-time quantitative polymerization chain reaction. Data show that photobiomodulation reduces the mRNA levels from ATM and p53, as well reduces mRNA levels from TRF1 and TRF2 at 25 and 75 mW in injured skeletal muscle. In conclusion, photobiomodulation alters mRNA relative levels from genes related to genomic and telomere stabilization in injured skeletal muscle.

KEYWORDS:

DNA; Laser; Muscle; Wistar rats

Photomed Laser Surg. 2018 Mar 23. doi: 10.1089/pho.2017.4393. [Epub ahead of print]

Aging Is a Sticky Business.

Sommer AP1.

Author information

1
Ulm, Germany .

Abstract

OBJECTIVE:

The objective of this work is to put forward a mechanism by which low-level light [red-to near infrared (NIR) laser or light emitting diodes (LED)] is instrumental in the process of accelerating the healing of wounds.

BACKGROUND DATA:

Interaction modalities of low-level light with oxidatively stressed cells and tissues are the focus of intense research efforts. Several models of the light/cell-interaction mechanism have been proposed. In the most popular model, cytochrome c oxidase is believed to play the role of the principal acceptor for red-to NIR photons.

METHODS:

Using as an illustrative example the successful LED treatment of an edematous limb ulcer, the results of recent in vitro tests and complementary laboratory experiments are presented and discussed.

RESULTS:

The most plausible mechanism of biostimulatory effect of red-to NIR light consists of its impact on the nanoscopic interfacial water layers in mitochondria and the extracellular matrix (ECM) where mitochondrial reactive oxygen species (ROS) induce an increase in the viscosity of the water layers bound to the predominantly hydrophilic surfaces in the intramitochondrial space as well as the ECM, where the process progressively propagates with age. The biostimulatory effect of red-to NIR light consists of counteracting the ROS-induced elevation of interfacial water viscosities, thereby instantly restoring the normal mitochondrial function, including the synthesis of adenosine triphosphate (ATP) by the rotary motor (ATP synthase).

CONCLUSIONS:

An understanding of the mechanism of interaction of red-to NIR light with mitochondria, cells, and tissues safeguards progress in the field of low-level light therapy (LLLT) and puts us in the position to design better therapies.

KEYWORDS:

ATP; LED; ROS; interfacial water viscosity; laser; mitochondria; wound

Neurobiol Aging. 2018 Feb 26;66:131-137. doi: 10.1016/j.neurobiolaging.2018.02.019. [Epub ahead of print]

Photobiomodulation reduces gliosis in the basal ganglia of aged mice.

El Massri N1, Weinrich TW2, Kam JH2, Jeffery G2, Mitrofanis J3.

Author information

1
Department of Anatomy F13, University of Sydney, Sydney, NSW, Australia.
2
Institute of Ophthalmology, University College London, London, England.
3
Department of Anatomy F13, University of Sydney, Sydney, NSW, Australia. Electronic address: john.mitrofanis@sydney.edu.au.

Abstract

This study explored the effects of long-term photobiomodulation (PBM) on the glial and neuronal organization in the striatum of aged mice. Mice aged 12 months were pretreated with PBM (670 nm) for 20 minutes per day, commencing at 5 months old and continued for 8 months. We had 2 control groups, young at 3 months and aged at 12 months old; these mice received no treatment. Brains were aldehyde-fixed and processed for immunohistochemistry with various glial and neuronal markers. We found a clear reduction in glial cell number, both astrocytes and microglia, in the striatum after PBM in aged mice. By contrast, the number of 2 types of striatal interneurons (parvalbumin+ and encephalopsin+), together with the density of striatal dopaminergic terminals (and their midbrain cell bodies), remained unchanged after such treatment. In summary, our results indicated that long-term PBM had beneficial effects on the aging striatum by reducing glial cell number; and furthermore, that this treatment did not have any deleterious effects on the neurons and terminations in this nucleus.

KEYWORDS:

Astrocytes; Caudate-putamen complex; Interneurons; Microglia; Substantia nigra

J Biophotonics. 2017 Dec 11. doi: 10.1002/jbio.201700282. [Epub ahead of print]

Aging of lymphoid organs: Can photobiomodulation reverse age-associated thymic involution via stimulation of extrapineal melatonin synthesis and bone marrow stem cells?

Odinokov D1, Hamblin MR2,3,4.

Author information

1
Department of Biomedical Engineering, Chinese University of Hong Kong, Hong Kong.
2
Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA.
3
Department of Dermatology, Harvard Medical School, Boston, MA, 02115, USA.
4
Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, 02139, USA.

Abstract

Thymic atrophy and the subsequent reduction in T cell production are the most noticeable age-related changes affecting lymphoid organs in the immune system. In fact thymic involution has been described as “programmed aging”. New therapeutic approaches such as photobiomodulation (PBM) may reduce or reverse these changes. PBM (also known as low-level laser therapy or LLLT) involves the delivery of non-thermal levels of red or near-infrared light that are absorbed by mitochondrial chromophores, in order to prevent tissue death and stimulate healing and regeneration. PBM may reverse or prevent thymic involution due to its ability to induce extrapineal melatonin biosynthesis via cyclic AMP or NF-kB activation, or alternatively by stimulating bone marrow stem cells that can regenerate the thymus. This perspective puts forward a hypotheses that PBM can alter thymic involution, improve immune functioning in aged people, and even extend lifespan.

Neurobiol Aging. 2017 Oct;58:140-150. doi: 10.1016/j.neurobiolaging.2017.06.025. Epub 2017 Jul 6.

Transcranial low-level laser therapy improves brain mitochondrial function and cognitive impairment in D-galactose-induced aging mice.

Salehpour F1, Ahmadian N2, Rasta SH3, Farhoudi M2, Karimi P2, Sadigh-Eteghad S4.

Author information

1
Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, Iran; Department of Medical Physics, Tabriz University of Medical Sciences, Tabriz, Iran.
2
Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, Iran.
3
Department of Medical Physics, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Medical Bioengineering, Tabriz University of Medical Sciences, Tabriz, Iran; School of Medical Sciences, University of Aberdeen, Aberdeen, UK.
4
Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz, Iran. Electronic address: Saeed.sadigetegad@gmail.com.

Abstract

Mitochondrial function plays a key role in the aging-related cognitive impairment, and photoneuromodulation of mitochondria by transcranial low-level laser therapy (LLLT) may contribute to its improvement. This study focused on the transcranial LLLT effects on the D-galactose (DG)-induced mitochondrial dysfunction, apoptosis, and cognitive impairment in mice. For this purpose, red and near-infrared (NIR) laser wavelengths (660 and 810 nm) at 2 different fluencies (4 and 8 J/cm2) at 10-Hz pulsed wave mode were administrated transcranially 3 d/wk in DG-received (500 mg/kg/subcutaneous) mice model of aging for 6 weeks. Spatial and episodic-like memories were assessed by the Barnes maze and What-Where-Which (WWWhich) tasks. Brain tissues were analyzed for mitochondrial function including active mitochondria, adenosine triphosphate, and reactive oxygen species levels, as well as membrane potential and cytochrome c oxidase activity. Apoptosis-related biomarkers, namely, Bax, Bcl-2, and caspase-3 were evaluated by Western blotting method. Laser treatments at wavelengths of 660 and 810 nm at 8 J/cm2 attenuated DG-impaired spatial and episodic-like memories. Also, results showed an obvious improvement in the mitochondrial function aspects and modulatory effects on apoptotic markers in aged mice. However, same wavelengths at the fluency of 4 J/cm2 had poor effect on the behavioral and molecular indexes in aging model. This data indicates that transcranial LLLT at both of red and NIR wavelengths at the fluency of 8 J/cm2 has a potential to ameliorate aging-induced mitochondrial dysfunction, apoptosis, and cognitive impairment.

KEYWORDS:

Aging; Apoptosis; D-galactose; Episodic-like memory; Mitochondrial function; Spatial memory; Transcranial low-level laser therapy

Exp Brain Res. 2017 Oct;235(10):3081-3092. doi: 10.1007/s00221-017-5048-7. Epub 2017 Jul 25.

No evidence for toxicity after long-term photobiomodulation in normal non-human primates.

Moro C1, Torres N1, Arvanitakis K2, Cullen K2, Chabrol C1, Agay D1, Darlot F1, Benabid AL1, Mitrofanis J3.

Author information

1
University of Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, 38000, Grenoble, France.
2
Department of Anatomy F13, University of Sydney, Camperdown, 2006, Australia.
3
Department of Anatomy F13, University of Sydney, Camperdown, 2006, Australia. john.mitrofanis@sydney.edu.au.

Abstract

In this study, we explored the effects of a longer term application, up to 12 weeks, of photobiomodulation in normal, naïve macaque monkeys. Monkeys (n = 5) were implanted intracranially with an optical fibre device delivering photobiomodulation (red light, 670 nm) to a midline midbrain region. Animals were then aldehyde-fixed and their brains were processed for immunohistochemistry. In general, our results showed that longer term intracranial application of photobiomodulation had no adverse effects on the surrounding brain parenchyma or on the nearby dopaminergic cell system. We found no evidence for photobiomodulation generating an inflammatory glial response or neuronal degeneration near the implant site; further, photobiomodulation did not induce an abnormal activation or mitochondrial stress in nearby cells, nor did it cause an abnormal arrangement of the surrounding vasculature (endothelial basement membrane). Finally, because of our interest in Parkinson’s disease, we noted that photobiomodulation had no impact on the number of midbrain dopaminergic cells and the density of their terminations in the striatum. In summary, we found no histological basis for any major biosafety concerns associated with photobiomodulation delivered by our intracranial approach and our findings set a key template for progress onto clinical trial on patients with Parkinson’s disease.

KEYWORDS:

670 nm; Behaviour; Macaque monkeys; Striatum; Substantia nigra; Tyrosine hydroxylase

Exp Brain Res. 2017 Oct;235(10):3081-3092. doi: 10.1007/s00221-017-5048-7. Epub 2017 Jul 25.

No evidence for toxicity after long-term photobiomodulation in normal non-human primates.

Moro C1, Torres N1, Arvanitakis K2, Cullen K2, Chabrol C1, Agay D1, Darlot F1, Benabid AL1, Mitrofanis J3.

Author information

1
University of Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, 38000, Grenoble, France.
2
Department of Anatomy F13, University of Sydney, Camperdown, 2006, Australia.
3
Department of Anatomy F13, University of Sydney, Camperdown, 2006, Australia. john.mitrofanis@sydney.edu.au.

Abstract

In this study, we explored the effects of a longer term application, up to 12 weeks, of photobiomodulation in normal, naïve macaque monkeys. Monkeys (n = 5) were implanted intracranially with an optical fibre device delivering photobiomodulation (red light, 670 nm) to a midline midbrain region. Animals were then aldehyde-fixed and their brains were processed for immunohistochemistry. In general, our results showed that longer term intracranial application of photobiomodulation had no adverse effects on the surrounding brain parenchyma or on the nearby dopaminergic cell system. We found no evidence for photobiomodulation generating an inflammatory glial response or neuronal degeneration near the implant site; further, photobiomodulation did not induce an abnormal activation or mitochondrial stress in nearby cells, nor did it cause an abnormal arrangement of the surrounding vasculature (endothelial basement membrane). Finally, because of our interest in Parkinson’s disease, we noted that photobiomodulation had no impact on the number of midbrain dopaminergic cells and the density of their terminations in the striatum. In summary, we found no histological basis for any major biosafety concerns associated with photobiomodulation delivered by our intracranial approach and our findings set a key template for progress onto clinical trial on patients with Parkinson’s disease.

KEYWORDS:

670 nm; Behaviour; Macaque monkeys; Striatum; Substantia nigra; Tyrosine hydroxylase

Exp Brain Res. 2017 Jun;235(6):1861-1874. doi: 10.1007/s00221-017-4937-0. Epub 2017 Mar 15.

Photobiomodulation-induced changes in a monkey model of Parkinson’s disease: changes in tyrosine hydroxylase cells and GDNF expression in the striatum.

El Massri N1, Lemgruber AP1, Rowe IJ1, Moro C2, Torres N2, Reinhart F2, Chabrol C2, Benabid AL2, Mitrofanis J3.

Author information

1
Department of Anatomy F13, University of Sydney, Sydney, 2006, Australia.
2
University of Grenoble Alpes, CEA, LETI, CLINATEC, MINATEC Campus, 38000, Grenoble, France.
3
Department of Anatomy F13, University of Sydney, Sydney, 2006, Australia. john.mitrofanis@sydney.edu.au.

Abstract

Intracranial application of red to infrared light, known also as photobiomodulation (PBM), has been shown to improve locomotor activity and to neuroprotect midbrain dopaminergic cells in rodent and monkey models of Parkinson’s disease. In this study, we explored whether PBM has any influence on the number of tyrosine hydroxylase (TH)+cells and the expression of GDNF (glial-derived neurotrophic factor) in the striatum. Striatal sections of MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-treated mice and monkeys and 6-hydroxydopamine (6OHDA)-lesioned rats that had PBM optical fibres implanted intracranially (or not) were processed for immunohistochemistry (all species) or western blot analysis (monkeys). In our MPTP monkey model, which showed a clear loss in striatal dopaminergic terminations, PBM generated a striking increase in striatal TH+ cell number, 60% higher compared to MPTP monkeys not treated with PBM and 80% higher than controls. This increase was not evident in our MPTP mouse and 6OHDA rat models, both of which showed minimal loss in striatal terminations. In monkeys, the increase in striatal TH+ cell number in MPTP-PBM cases was accompanied by similar increases in GDNF expression, as determined from western blots, from MPTP and control cases. In summary, these results offer insights into the mechanisms by which PBM generates its beneficial effects, potentially with the use of trophic factors, such as GDNF.

KEYWORDS:

670 nm; 6OHDA; Caudate; MPTP; Near infrared light; Putamen

 2016 Aug;31(6):1161-7. doi: 10.1007/s10103-016-1956-1. Epub 2016 May 25.

Lowlevel infrared laser modulates muscle repair and chromosome stabilization genes in myoblasts.

Author information

1
Laboratório de Pesquisa em Células Tronco, Departamento de Histologia e Embriologia, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, fundos, Vila Isabel, Rio de Janeiro, 20551030, Brazil.
2
Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, fundos, 4° andar, Vila Isabel, Rio de Janeiro, 20551030, Brazil.
3
Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, fundos, 4° andar, Vila Isabel, Rio de Janeiro, 20551030, Brazil. adnfonseca@yahoo.com.br.
4
Departamento de Ciências Fisiológicas, Instituto Biomédico, Universidade Federal do Estado do Rio de Janeiro, Rua Frei Caneca, 94, Rio de Janeiro, 20211040, Brazil. adnfonseca@yahoo.com.br.

Abstract

Infrared laser therapy is used for skeletal muscle repair based on its biostimulative effect on satellite cells. However, shortening of telomerelength limits regenerative potential in satellite cells, which occurs after each cell division cycle. Also, laser therapy could be more effective on non-physiologic tissues. This study evaluated lowlevel infrared laser exposure effects on mRNA expression from muscle injury repair and telomere stabilization genes in myoblasts in normal and stressful conditions. Laser fluences were those used in clinical protocols. C2C12 myoblast cultures were exposed to lowlevel infrared laser (10, 35, and 70 J/cm(2)) in standard or normal (10 %) and reduced (2 %) fetal bovine serum concentrations; total RNA was extracted for mRNA expression evaluation from muscle injury repair (MyoD and Pax7) and chromosome stabilization (TRF1 and TRF2) genes by real time quantitative polymerization chain reaction. Data show that lowlevelinfrared laser increases the expression of MyoD and Pax7 in 10 J/cm(2) fluence, TRF1 expression in all fluences, and TRF2 expression in 70 J/cm(2) fluence in both 10 and 2 % fetal bovine serum. Lowlevel infrared laser increases mRNA expression from genes related to muscle repair and telomere stabilization in myoblasts in standard or normal and stressful conditions.

KEYWORDS:

Low level laser; MyoD; Pax7; TRF1; TRF2

[Experimental study of effect of low power laser on telomere length of cells].

[Article in Chinese]

Author information

1
Department of Physiology, Guangxi Medical University, Nanning 530021, China.

Abstract

To investigate the effect of low power helium neon laser (He-Ne laser) on the telomere length of human fetal lung diploid fibroblast (2BS) cell, we used the laser (gamma = 632. 8 nm, P = 2 mW) to treat the young 2BS cells. Cell growth and proliferation was observed through MTT method after treating with low power laser. The relative telomere length of 2BS cells was detected by fluorescence real-time quantitative PCR (q-PCR). The results showed that the cells of the treated groups grew better than the untreated groups. The telomereDNA length of the old 2BS cells, treated by low power He-Ne laser when they were young, was longer than that of untreated group. The results of the present study indicated that the low power He-Ne laser might decrease shortening rate of telomere and delay the aging of cells. Therefore, this study provides the experimental basis for us to further investigate the effect of low power laser on cell aging at the gene level.

Vopr Kurortol Fizioter Lech Fiz Kult.  2011 Jul-Aug;(4):39-42.

The influence of pulsed infrared laser radiation on the hormone production in the thymus (an experimental study).

[Article in Russian]
[No authors listed]

Abstract

Local irradiation with pulsed (1500 Hz) low-energy infrared laser light of the thymus and thyroid gland region caused well-apparent stimulation of alpha-1-thymosin production in the healthy animals and normalized its level in the stressed ones. Similar stimulation of alpha-1-timosine biosynthesis was observed in an experiment with direct laser irradiation of the cultured HTSC epitheliocytes from the human thymus.

Adv Gerontol. 2010;23(4):547-53.

Induced thymus aging: radiation model and application perspective for low intensive laser radiation.

[Article in Russian]
Sevost’ianova NN, Trofimov AV, Lin’kova NS, Poliakova VO, Kvetno IM.

Abstract

The influence of gamma-radiation on morphofunctional state of thymus is rather like as natural thymus aging. However gamma-radiation model of thymus aging widely used to investigate geroprotectors has many shortcomings and limitations. Gamma-radiation can induce irreversible changes in thymus very often. These changes are more intensive in comparison with changes, which can be observed at natural thymus aging. Low intensive laser radiation can not destroy structure of thymus and its effects are rather like as natural thymus aging in comparison with gamma-radiation effects. There are many parameters of low intensive laser radiation, which can be changed to improve morphofunctional thymus characteristics in aging model. Using low intensive laser radiation in thymus aging model can be very perspective for investigations of aging immune system.

Biofizika. 2007 Jan-Feb;52(1):137-40.

Protective effect of low-power laser radiation in acute toxic stress.

[Article in Russian]
Novoselova EG, Glushkova OV, Khrenov MO, Chernenkov DA, Lunin SM, Novoselova TV, Chudnovski? VM, Iusupov VI, Fesenko EE.

Abstract

The effect of preliminary short-term irradiation with He-Ne laser light (632.8 nm, 0.2 mW/cm2) of the thymus zone projection of male NMRI mice subjected to acute toxic stress on the responses of immune cells was studied. Stress was modeled by lipopolysaccharide injection, 250 mg/100 g of body weight, which induced a significant increase in the production of several macrophage cytokines, IL-1alpha, IL-1beta, IL-6, IL-10 and TNF-alpha. A single irradiation with laser light did not provoke considerable variations in NO production in cells but induced an enhancement in the production of heat shock proteins Hsp25, Hsp70, and Hsp90. Nevertheless, when irradiation with red laser light was applied prior to toxic stress, considerable normalization of production of nearly all cytokines studied and nitric oxide was observed. Moreover, the normalization of production of heat shock proteins has been shown in these conditions. Thus, preliminary exposure of a small area of animal skin surface provoked a significant lowering in the toxic effect of lipopolysaccharide.

Izv Akad Nauk Ser Biol. 2006 Nov-Dec;(6):667-79.

Structure peculiarities of muscle regenerates and state of thymus under He-Ne laser therapy in different periods after muscle trauma.

[Article in Russian]
Buliakova NV, Azarova VS.

Abstract

We studied the gastrocnemius muscle regeneration and the reactive changes in thymus of rats under different regimens of He-Ne laser therapy of both operated legs (632.8 nm; 2.5-3.0 mW/cm(2) ). Laser radiation (10 exposures by 3 min within 1-15 days after muscle trauma, 4.5-5.4 J/cm(2) total dose per each leg) stimulated inflammatory reaction, muscle healing and favored preservation of muscle tissue in regenerates. The changes in thymus mass, its histological structure, size of cortex and thymocite mitotic index pointed to the increase of the functional load on thymus and delay of its recovery. The same dose of laser therapy of muscles within 16-30 days after trauma led to the increase of muscle tissue sclerotization in regenerates. The reactive changes in thymus were less pronounced. Threefold decrease of laser dose (10 exposures by 1 min for 1-15 days, 1.5-1.8 J/cm(2)) suppressed inflammatory reaction, impaired the muscle regeneration. The increase of functional activity in thymus was not observed.

Minim Invasive Ther Allied Technol. 2006;15(5):277-85.

Regeneration of skeletal muscles and state of thymus in gamma-irradiated rats under laser therapy of the area of muscle trauma.

Bulyakova NV, Azarova VS.

Source

A N Severtzov Institute of Ecology & Evolution, Russian Academy of Sciences, Moscow, Russia. admin@sevin.ru

Abstract

The gamma-irradiation of adult rats with a semi-lethal dose (6 Gy) suppressed the posttraumatic regeneration of skeletal muscles and brought about considerable destructive changes in the thymus. The effect of He-Ne laser radiation at a total dose 4.5-5.4 J/cm2 at each operated leg in irradiated rats stimulated the regenerative capacity of skeletal muscle tissue, the healing of skin-muscle wound, and the processes of postradiation recovery in thymus cells (a decrease of chromosome aberrations). The histological structure of regenerates had more muscle pattern. At the same time, the positive dynamics of regenerative processes in muscles was achieved by an increased functional load on the thymus. To stimulate the regeneration of irradiated muscles on the background of a more moderate load on the thymus, the prolonged period of laser therapy and fragmentary distribution of laser exposures during muscle regeneration were preferable. Wound healing improved visibly. Nor formation of chronic radiation ulcers on operated shins was observed.

Biofizika. 2006 Jan-Feb;51(1):123-35.

Effects of exposure of different skin areas to low-power laser light.

[Article in Russian]
Glushkov OV, Novoselova EG, Cherenkov DA, Novoselova TV, Khrenov MO, Lunin SM, Chudnovski? VM, Iusupov VI, Fesenko EE.

Abstract

The effect of helium-neon laser light of extremely low power of 0.2 mW/cm2 and wavelength 632.8 nm on the immune status of mice bearing solid tumors was studied. The evaluation of the status of tumor-bearing animals was provided by taking into account the number of immune cells, cytokine concentration (tumor necrosis factor, interleukin 2, production of nitric oxide, expression of heat shock proteins (Hsp70 and Hsp90), and activity of natural killers. The model of a solid tumor was formed by subcutaneous injection of Ehrlich carcinoma cells, and average life span of tumor-bearing mice achieved about 55 days. Different areas of the skin of tumor-bearing mice were subjected either to a single (1 min, dose 0.012 J/cm3) or repeated exposure to laser light (1 min, 48-h intervals, 30 days). Two different areas were irradiated: the thymus projection area or a hind limb with solid tumors. The results showed that chronic exposure of tumor-bearing mice in the thymus projection area, and especially, hind limb, reduced the resistance, which manifested itself in the acceleration of tumor growth and a tendency of mouse life span to decrease. On the contrary, a single exposure stimulated the antitumor immunity for several days after the exposure. The results show the expediency of further investigation of the immunomodulative effects of low-power laser light and the necessity of monitoring the immune system during laser therap