RESUMEN
INTRODUCTION: Authors of numerous publications have proved the therapeutic effect of laser irradiation on biological material, but the mechanisms at cellular and subcellular level are not yet well understood. OBJECTIVE: The aim of this study was to assess the effect of laser radiation emitted by the MLS M1 system (Multiwave Locked System) at two wavelengths (808 nm continuous and 905 nm pulsed) on the stability and fluidity of liposomes with a lipid composition similar to that of human erythrocyte membrane or made of phosphatidylocholine. MATERIAL AND METHODS: Liposomes were exposed to low-energy laser radiation at surface densities 195 mW/cm2 (frequency 1,000 Hz) and 230 mW/cm2 (frequency 2,000 Hz). Different doses of radiation energy in the range 0-15 J were applied. The surface energy density was within the range 0.46 - 4.9 J/cm 2. RESULTS: The fluidity and stability of liposomes subjected to such irradiation changed depending on the parameters of radiation used. CONCLUSIONS: Since MLS M1 laser radiation, depending on the parameters used, affects fluidity and stability of liposomes with the lipid content similar to erythrocyte membrane, it may also cause structural and functional changes in cell membranes.
Asunto(s)
Membrana Celular/efectos de la radiación , Lípidos de la Membrana/efectos de la radiación , Eritrocitos/efectos de la radiación , Humanos , Rayos Láser , Liposomas/química , Liposomas/efectos de la radiación , Terapia por Luz de Baja Intensidad/instrumentación , Fluidez de la Membrana/efectos de la radiaciónRESUMEN
This paper examines a perspective on the use of newly engineered nanomaterials as effective and safe carriers of genes for the therapy of cancer. Three different groups of cationic dendrimers (PAMAM, phosphorus and carbosilane) were complexed with anticancer siRNA and their biophysical properties of the dendriplexes analyzed. The potential of the dendrimers as nanocarriers for anticancer siBcl-xl, siBcl-2, siMcl-1 siRNAs and a siScrambled sequence was explored. Dendrimer/siRNA complexes were characterized by methods including fluorescence, zeta potential, dynamic light scattering, circular dichroism, gel electrophoresis and transmission electron microscopy. Some of the experiments were done with heparin to check if siRNA can be easily disassociated from the complexes, and whether released siRNA maintains its structure after interaction with the dendrimer. The results indicate that siRNAs form complexes with all the dendrimers tested. Oligoribonucleotide duplexes can be released from dendriplexes after heparin treatment and the structure of siRNA is maintained in the case of PAMAM or carbosilane dendrimers. The dendrimers were also effective in protecting siRNA from RNase A activity. The selection of the best siRNA carrier will be made based on cell culture studies (Part B).
Asunto(s)
Dendrímeros/química , Fósforo/química , ARN Interferente Pequeño/química , Tratamiento con ARN de Interferencia/métodos , Silanos/química , Transfección , Dicroismo Circular , Electroforesis en Gel de Agar , Regulación Neoplásica de la Expresión Génica , Heparina/química , Humanos , Luz , Microscopía Electrónica de Transmisión , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/terapia , Conformación de Ácido Nucleico , Tamaño de la Partícula , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Dispersión de Radiación , Espectrometría de Fluorescencia , Transfección/métodos , Proteína bcl-X/genética , Proteína bcl-X/metabolismoRESUMEN
The biostimulating activity of low level laser radiation of various wavelengths and energy doses is widely documented in the literature, but the mechanisms of the intracellular reactions involved are not precisely known. The aim of this paper is to evaluate the influence of low level laser radiation from an multiwave locked system (MLS) of two wavelengths (wavelength = 808 nm in continuous emission and 905 nm in pulsed emission) on the human erythrocyte membrane and on the secondary structure of human serum albumin (HSA). Human erythrocytes membranes and HSA were irradiated with laser light of low intensity with surface energy density ranging from 0.46 to 4.9 J cm(-2) and surface energy power density 195 mW cm(-2) (1,000 Hz) and 230 mW cm(-2) (2,000 Hz). Structural and functional changes in the erythrocyte membrane were characterized by its fluidity, while changes in the protein were monitored by its secondary structure. Dose-dependent changes in erythrocyte membrane fluidity were induced by near-infrared laser radiation. Slight changes in the secondary structure of HSA were also noted. MLS laser radiation influences the structure and function of the human erythrocyte membrane resulting in a change in fluidity.