808-nm laser therapy with a flat-top handpiece photobiomodulates mitochondria activities of Paramecium primaurelia (Protozoa).
- 1Department of Earth, Environmental and Life Sciences, Protistology Laboratory, University of Genoa, Corso Europa, 26, 16132, Genoa, Italy.
- 2Department of Pharmacy, Biochemistry Laboratory, University of Genoa, Viale Benedetto XV, 3, 16132, Genoa, Italy.
- 3Department of Surgical Sciences and Integrated Diagnostic, University of Genoa, Largo R. Benzi, 10, 16132, Genoa, Italy.
- 4Department of Surgical Sciences and Integrated Diagnostic, University of Genoa, Largo R. Benzi, 10, 16132, Genoa, Italy. email@example.com.
Photobiomodulation is proposed as a non-linear process, and only low-level laser therapy (LLLT) is assumed to stimulate exposed cells, whereas high powered laser and fluences can cause negative effects, exhausting the cell’s energy reserve as a consequence of excessive photon-based stimulation. In our work, we investigated and compared the effects of 808-nm diode laser (CW) with a new flat-top handpiece. To this purpose, we tested the photobiomodulation effects of 1 and 3 J/cm2 fluence, both generated by 100 mW or 1 W of laser power and of 64 J/cm2 of fluence generated by 100 mW, 1 W, 1.5 W or 2 W, as expressed through oxygen consumption and ATP synthesis of Paramecium. Data collected indicates the incremental consumption of oxygen through irradiation with 3 J/cm2-100 mW or 64 J/cm2-1 W correlates with an increase in Paramecium ATP synthesis. The Paramecium respiration was inhibited by fluences 64 J/cm2-100 mW or 64 J/cm2-2 W and was followed by a decrease in the endogenous ATP concentration. The 1 J/cm2-100 mW or 1 W and 3 J/cm2-1 W did not affect mitochondrial activity. The results show that the fluence of 64 J/cm2-1 W more than the 3 J/cm2-100 mW causes greater efficiency in Paramecium mitochondria respiratory chain activity. Our results suggest that thanks to flat-top handpiece we used, high fluences by high-powered laser have to be reconsidered as an effective and non-invasive therapy. Possible associated benefits of deeper tissue penetration would increase treatment effectiveness and reduced irradiation time.
The protozoan, Paramecium primaurelia, as a non-sentient model to test laser light irradiation: The effects of an 808nm infrared laser diode on cellular respiration.
Photobiomodulation (PBM) has been used in clinical practice for more than 40 years. Unfortunately, conflicting literature has led to the labelling of PBM as a complementary or alternative medicine approach. However, past and ongoing clinical and research studies by reputable investigators have re-established the merits of PBM as a genuine medical therapy, and the technique has, in the last decade, seen an exponential increase in the numbers of clinical instruments available, and their applications. This resurgence has led to a clear need for appropriate experimental models to test the burgeoning laser technology being developed for medical applications. In this context, an ethical model that employs the protozoan, Paramecium primaurelia, is proposed. We studied the possibility of using the measure of oxygen consumption to test PBM by irradiation with an infrared or near-infrared laser. The results show that an 808nm infrared laser diode (1W; 64J/cm2) affects cellular respiration in P. primaurelia, inducing, in the irradiated cells, a significantly (p < 0.05) increased oxygen consumption of about 40%. Our findings indicate that Paramecium can be an excellent tool in biological assays involving infrared and near-infrared PBM, as it combines the advantages of in vivo results with the practicality of in vitro testing. This test represents a fast, inexpensive and straightforward assay, which offers an alternative to both traditional in vivo testing and more expensive mammalian cellular cultures.
Paramecium: A Promising Non-Animal Bioassay to Study the Effect of 808?nm Infrared Diode Laser Photobiomodulation.
Abstract Objective: Photobiostimulation and photobiomodulation (PBM) are terms applied to the manipulation of cellular behavior using low intensity light sources, which works on the principle of inducing a biological response through energy transfer. The aim of this investigation was to identify a laboratory assay to test the effect of an infrared diode laser light (808 nm) on cell fission rate.
Materials and methods: Sixty cells of Paramecium primaurelia were divided in two groups of 30. The first group (test group) was irradiated, at a temperature of 24°C, for 50 sec by a 808 nm diode laser with a flat top handpiece [1 cm of spot diameter, 1 W in continuous wave (CW), 50 sec irradiation time, 64 J/cm2 of fluence]. The second group (control group) received no laser irradiation. All cells were transferred onto a depression slide, fed, and incubated in a moist chamber at a temperature of 24°C. The cells were exposed and monitored for 10 consecutive fission rates. Changes in temperature and pH were also evaluated.
Results: The exposed cells had a fission rate rhythm faster than the control cells, showing a binary fission significantly (p<0.05) shorter than unexposed cells. No significant effects of laser irradiation on pH and temperature of Paramecium’s lettuce infusion medium were observed.
Conclusions: The 808 nm infrared diode laser light, at the irradiation parameters used in our work, results in a precocious fission rate in P. primaurelia cells, probably through an increase in metabolic activity, secondary to an energy transfer.