Manipulating the mitochondria activity in human hepatic cell line Huh7 by low-power laser irradiation

Abstract

Low-power laser irradiation of red light has been recognized as a promising tool across a vast variety of biomedical applications. However, deep understanding of the molecular mechanisms behind laser-induced cellular effects remains a significant challenge. Here, we investigated mechanisms involved in the death process in human hepatic cell line Huh7 at a laser irradiation. We decoupled distinct cell death pathways targeted by laser irradiations of different powers. Our data demonstrate that high dose laser irradiation exhibited the highest levels of total reactive oxygen species production, leading to cyclophilin D-related necrosis via the mitochondrial permeability transition. On the contrary, low dose laser irradiation resulted in the nuclear accumulation of superoxide and apoptosis execution. Our findings offer a novel insight into laser-induced cellular responses, and reveal distinct cell death pathways triggered by laser irradiation. The observed link between mitochondria depolarization and triggering ROS could be a fundamental phenomenon in laser-induced cellular responses.

Modulation of Living Cell Behavior with Ultra‐Low Fouling Polymer Brush Interfaces

“…Cytotoxic activity of the brushes was determined quantitatively by a fluorimetric assay utilizing calcein AM and propidium iodide (PI) (both dyes from Thermo Fisher Scientific), as described earlier 50. This cell viability assay was based on the ability of calcein AM to be retained within live cells, inducing an intense uniform green fluorescence and EthD‐1 to bind the nuclei of damaged cells, thus producing a bright red fluorescence in dead cells 51.…”

“…[49] Cell Viability Assay: Cytotoxic activity of the brushes was determined quantitatively by a fluorimetric assay utilizing calcein AM and propidium iodide (PI) (both dyes from Thermo Fisher Scientific), as described earlier. [50] This cell viability assay was based on the ability of calcein AM to be retained within live cells, inducing an intense uniform green fluorescence and EthD-1 to bind the nuclei of damaged cells, thus producing a bright red fluorescence in dead cells. [51] Prior to the cell seeding, all experimental substrates were sterilized by treatment with 70% ethanol for 20 min, followed by UV exposure for 1 h. For all cell experiments in this study, the cells were seeded on the sterilized substrates at an initial density of 25 000 cells cm -2 and were maintained under standard cell culture conditions (37 °C, 5% CO 2 ).…”

Optical Properties of Buffers and Cell Culture Media for Optofluidic and Sensing Applications

“…Knowledge of interactions between light and various cultured organisms is essential for therapeutic [4] or detection [5] purposes. The most common optical methods are used to monitor cell growth condition and are based on densitometry evaluation [3].…”

“…For this reason, some media contain a pH-dependent dye, changing their color when they become older, they accumulate cell metabolites, or there are products of nutrient degradation. This effect seems to be important mainly in colorimetric and spectrophotometric analyses, especially when the color of the used media disturbs the measurement [2][3][4]. For the majority of living cells, monitoring is performed in the visible and near-infrared spectral range (λ = 390-700 nm) to reduce the energy supplied to the cells and to maintain the properties of the dyes used in the analysis.…”

Remote Actuation of Apoptosis in Liver Cancer Cells via Magneto-Mechanical Modulation of Iron Oxide Nanoparticles

“…Therefore, the next logical step was to study whether our PMF-induced cell death is associated with the impairment of mitochondrial function. To answer this question, we utilized a well-established methodology based on JC-1 staining [52][53][54]. JC-1 mitochondria membrane potential (∆mΦ) assessment is possible due to the selectivity of the dye in mitochondria labeling.…”