RESUMO
OBJECTIVE: The aim of the present study was to analyze the effects of photobiomodulation using a 904-nm diode laser at two energy densities (6 J/cm(2) and 50 mJ/cm(2)) on L929 fibroblast cells. BACKGROUND: Low-power laser irradiation (LPLI) is a non-pharmacological resource that induces important in vitro photobiomodulation on cell cultures and tissues. METHODS: Irradiation was performed for three days at 24-h intervals. After each interval, the cells were stained with MitoTracker Orange and DioC6 dyes to assess the photobiomodulatory effects of irradiation on mitochondrial activity and changes in the endoplasmic reticulum. The MTT assay [3-(4.5-dimethylthiazol-2-yl)-2.5 diphenyltetrazolium bromide] was used to evaluate cell proliferation. RESULTS AND CONCLUSIONS: The fluorescence microscopy assessment of mitochondria and endoplasmic reticulum in cells irradiated with 6 J/cm(2) and 50 mJ/cm(2) demonstrated intense mitochondrial activity, which was confirmed by DioC6 staining. Reticular activity was observed stemming from increased protein synthesis. Photobiomodulation with 50 mJ/cm(2) was slightly higher than with 6 J/cm(2), as demonstrated by fluorescence microscopy results. Photobiomodulation was also time-dependent, with better results 72-h after irradiation.
Assuntos
Divisão Celular/efeitos da radiação , Lasers , Animais , Células Cultivadas , Retículo Endoplasmático/efeitos da radiação , Fibroblastos/efeitos da radiação , Camundongos , Microscopia de Fluorescência , Mitocôndrias/efeitos da radiação , Sais de Tetrazólio , Fatores de TempoRESUMO
Physiotherapists consider ultrasound an indispensable tool, which is commonly employed in clinical practice as a treatment aid for musculoskeletal dysfunctions. The aim of our study has been to analyze fibroblast cell structures following low-intensity pulsed ultrasonic irradiation. Fibroblast cell cultures irradiated with ultrasound were analyzed through electron microscopy to determine an ideal irradiation beam that preserved cell morphology and integrity. Analysis by fluorescence microscopy and transmission electron microscopy was used to follow morphological changes of the nucleus and cytoskeleton following different ultrasound irradiation intensities. According to the parameters used in the pulsed irradiation of fibroblast cultures, control over the intensity employed is fundamental to the optimal use of therapeutic ultrasound. Cell cultures submitted to low-intensity pulsed ultrasonic irradiation (0.2-0.6 W/cm2) at 10% (1:9 duty cycle) and 20% (2:8 duty cycle) maintained shape and cellular integrity, with little damage. In the group irradiated with an intensity of 0.8 W/cm2, a loss of adhesion was observed along with an alteration in the morphology of some cells at an intensity of 1.0 W/cm2, which resulted in the presence of cellular fragments and a decrease of adhering cells. In cells irradiated at 2.0 W/cm2, there was a complete loss of adhesion and aggregation of cellular fragments. The present study confirms that biophysical properties of pulsed ultrasound may accelerate proliferation processes in different biological tissues.
Assuntos
Fibroblastos , Ultrassom , Animais , Linhagem Celular , Forma Celular , Fibroblastos/diagnóstico por imagem , Fibroblastos/ultraestrutura , Camundongos , UltrassonografiaRESUMO
Terapia fotodinâmica (TFD) vem sendo considerada um moderno tratamento para o câncer e severas outras condições médicas.O presente estudo tem por objetivo analisar as alterações morfológicas e ultraestruturais de células neoplásicas Hep-2 submetidas a TFD utilizando a Zinco Ftalocianina.Células Hep-2 foram cultivadas de maneira padrão com meio MEM, incubadas com a ZnPc na concentração 9mM por 1 hora, irradiadas com um laser de diodo, analisadas através de técnicas de Microscopia de Fluorescência utilizando marcadores específicos (DAPI e JC-1) e Microscopia Eletrônica de Transmissão. As células neoplásicas Hep-2 submetidas a TFD mostraram-se fotodanificadas morfológica e ultraestruturalmente, sendo possível observar algumas alterações nas organelas celulares. Portanto, pode-se concluir que após TFD utilizando a ZnPc estas células sofreram morte por apoptose...
Photodynamic Therapy (PDT) have been considered a modern treatment for cancer and several others medicalconditions. The present study has for objective to analyze the morphological and ultrastructural alterations of Hep-2 neoplasic cells submitting to PDT using a Zinc Phthalocyanine. Hep-2 cells were cultivated of standard form with MEM medium, incubated with the ZnPc at9mM concentration for 1 hour, irradiated with a diode laser, analyzed through of technique of Fluorescence Microcopy using specific staining (DAPI and JC-1) and Transmission Electronic Microscopy. The Hep-2 neoplasic cells submitted to PDT presented photodamaged morphological and ultrastructurally, have been possible to observe some alterations in the cell rganelles.Therefore, we can conclude that after PDT using the ZnPc these cells suffer death for apoptosis...