The influence of ultrasonic radiation of low intensity in cultured fibroblast cells

Abstract

Introduction:In vitro and in vivo put in evidence that the Low Intensity Pulsed Ultrasound therapy exerts a significant influence on cell function (cytoskeleton organization, stimulation of mitochondrial activity, ATP levels and plasma membrane). Objective: This study will analyze the radiation of low intensity pulsed ultrasound in fibroblast cells L 929. Method: In this study are presented the data from each exposure group average and standard deviation in each moment of evaluation (24 hours, 48 hours and 72 hours). The control group (received no radiation), 0.2 W/cm2 with 10% pulse regime (1: 9 duty cycle), 0.2 W / cm2 with 20% pulse regime (2: 8 cycle work), 0.4 W/cm2 with pulse scheme 10% (1: 9 duty cycle), 0.4 W/cm2 with pulse scheme 20% (2: 8 duty cycle). The analyzes will be performed through optical microscopy, MTT method 3 -(4,5-dimethylthiazol-2-yl) -2,5 diphenyl tetrazolium bromide, within the incubation times of 24, 48 and 72 hours. Results: Given the above study, the results presented in this project will be directed to increase the stimulation process and proliferation of fibroblast cells from the pulsed ultrasonic irradiation of low intensity, correlating with the healing process, neovascularization and repair. Conclusion: Therefore, the study of the effect of ultrasound from cell culture provides us with a simple and informative model on the significant aspects of the use of physical therapy in vivo system.

Effect of therapeutic ultrasound of low intensity pulsed and continuous in fibroblastic cells in vitro

“…(14,30) Finally, other authors verified in a similar protocol, in vitro, with L929 fibroblasts, a statistically significant effect on cell growth with pulsed and low intensity (0.4 W/cm 2 ), regimes, supporting the thesis that the interactions between intensity, frequency and pulse rate are strictly correlated to tissue repair phases. (8)…”

“…(4,5) On the other hand, the second, athermic, obtained in the output with pulses, is usually directed to the treatment of more severe or acute injuries, to improve the quality and speed of the recovery without increasing the local temperature. (6) In this sense, several authors report the efficiency of low intensity ultrasound in the percentage increase of viable cells cultured in vitro, with acceleration of proliferation and, (7)(8)(9) with the continuous, relevant therapeutic effects both in vivo and in vitro. (1,10) Furthermore, in the continuous mode, effects on the expression of cartilage specific mRNA in chondrocyte culture, (11) hypertrophy of muscle fibers, (1) or with pulsed modulation in biosynthetic activity and expression of integrins (12) and stimulation of anti-inflammatory systems in synovial membrane cells.…”

“…(13) It is worth mentioning that although the effects of ultrasound have already been well described, the ideal dose-effect relationship still needs to be better elucidated and delimited. (7)(8)(9)14) MTP&RehabJournal 2017, 15: 459 In this way, this study aimed to evaluate the influence of pulsed and continuous ultrasound irradiation on the viability of L929 fibroblast cells in vitro.…”

Ultrasonic therapy modulates the expression of genes related to neovascularization and inflammation in fibroblasts

“…anti-inflammatory signaling (decrease of leucocytes and macrophages), increase of metabolic reactions, microcirculation stimulation and angiogenesis, and, finally, fibroblastic activation. 3,4 From these meanings, we can highlight more specifically three biological events, which together corroborate in the potentiation of tissue healing.…”

“…In the clinical practice, ultrasound is widely used in the most diverse skeletal muscle dysfunctions, whether acute or chronic, 1,2 especially because it is an economical, safe, non-invasive physical procedure ,with healing capacity and considered a promising modality as an alternative to surgery. [3][4][5][6] Since 1952, after its implantation by the American Council of Physical Medicine and Rehabilitation, its relation with osteomyoarticular injuries has been a constant target of study. 7,8 However, clinical practice still adopts a multiplicity of dosimetries, i.e.…”