Apoptotic Effects And Spectral Characteristics Study Of Cells After Expose To Terahertz Radiation

The potential impact of terahertz radiation on biological systems is an important part of many application development projects based on biological safety,and it is important to assess the potential hazards and impacts of terahertz radiation on biological systems in a timely manner.Numerous studies have shown that the early views of non-destructive of terahertz radiation interact with organisms is not fully established at the cellular level,and the impact is also different.In addition to safety assessment,these effects can also provide a theoretical basis for new diagnostic methods based on terahertz technology.In this paper,the biological effects and spectral characteristics of mouse brain microvascular endothelial cells(bEnd.3)and the apoptosis of mouse ganglion retinal cells(RGC-5)under low-power terahertz time domain systems.Excessive apoptosis of retinal ganglion cells is the main cause of eye diseases such as glaucoma,so it is important to study the apoptotic effects of retinal ganglion cell.Firstly,we performed the mouse ganglion retinal cells exposed to the terahertz radiation for 5,10,20,30 and 40 minutes,then detected the apoptosis of cells after exposure for 0,6 and 12 hours.The results found that whether it was 0 hours,6 hours or 12 hours after exposure,the apoptosis rate decrease of cells was compared with the controls.It is indicated that this characteristic of terahertz radiation has a certain inhibitory effect on the increase of apoptosis of mouse retinal ganglion cells in this condition.It provides an in vitro cytological basis for the treatment of ocular diseases such as glaucoma,providing a potential for low-power broadband pulsed terahertz radiation as a possible therapeutic tool.In addition,brain microvascular endothelial cells are the main component of the blood-brain barrier,and its death will cause the blood-brain barrier to break and cause brain damage.We combine terahertz spectral characterization and evaluates the cellular responses and spectral characterization of bEnd.3 cells exposed to low power at a frequency of 0.1-3.5THz terahertz radiation for 10,20 and 30 minutes.During the experiment,the infrared camera was used to monitor the cell temperature during the exposure in real time and record the temperature values and infrared photos at various time points.The morphological changes ofthe cells before and after terahertz irradiation were observed by light microscopy.The apoptosis and cycle of the cells were detected by flow cytometry at 0 and 12 hours after exposure.The terahertz spectral data of the cells were collected in real time during irradiation.The experimental results show that there is almost no temperature change in the cell during the exposure process.At the same time,there was almost no significant change in cell morphology before and after irradiation.The results of apoptosis showed that the cells were detected at 0 hours after exposure,and the apoptotic rate decreased with the increase of exposure time.However,the results of the 12 hours after exposure showed that the apoptotic rate increased sharply.In the cell cycle analysis results,we found that the number of cells in the G0/G1 phase decreased with the exposure time at 0 hours after exposure,while the number of cells in the G2/M phase increased with the exposure time.But was detected 12 hours after exposure,the result is the opposite,the trend matches the trend of apoptosis.It is shown that even low-power terahertz radiation can have a detrimental effect on brain microvascular endothelial cells,but this effect does not manifest immediately after irradiation,but occurs at a certain time after exposure.Since the cell is a dielectric system,we calculated the complex permittivity of the cells at different exposure times(10,20,and 30 minutes)after collecting the spectral data of the cell exposure.The results of the analysis revealed that the dielectrical loss(the imaginary part of the complex permittivity)decreases with increasing exposure time,which may be caused the change in the solubility of some ions or proteins in the cell.At the same time,So we take advantage of this trend to investigate the relationship between changes in cell complex permittivity and apoptosis,we normalized the time domain spectral data of cells and found that it has a good match with the change of apoptotic rate of biological detection.it is proved that the terahertz time domain spectrometer is an effective method for non-invasive,label-free,real-time detection of cell death.