Presentation Title

Carbon black nanoparticles disrupt mitochondrial dynamics in human lung cells

Faculty Mentor

Dr. Jay Brewster

Start Date

18-11-2017 10:00 AM

End Date

18-11-2017 11:00 AM

Location

BSC-Ursa Minor 62

Session

Poster 1

Type of Presentation

Poster

Subject Area

biological_agricultural_sciences

Abstract

Carbon black (CB) is the primary nanoparticulate component of environmental pollution from fossil fuel combustion. Prior research has demonstrated that CB induces apoptosis, or programmed cell death, upon accumulation of CB via receptor-mediated endocytosis. The cellular consequences of CB incorporation are not well characterized. Human Bronchial Epithelial cells were used for all analyses described here. In evaluating CB incorporation into cells, we found a dose-dependent accumulation of CB that continues over several days. This identified CB as a stress dependent upon accumulation over time though acute affects have been noted in these studies. CB exposure causes an elevation of reactive oxygen species (ROS) within 8 hours of initial exposure. This result, along with observed abnormalities in mitochondrial dynamics in CB exposed cells garnered interest in mitochondria. CB concentrations ranging as low as 25 µg/ml induce a significant decrease in mitochondrial perinuclear localization at 36 and 48-hour time-points. Small/punctate mitochondrial numbers increased significantly with CB dosage over a period of 24-hours, which is consistent with mitochondrial stress/dysfunction. Live cell imaging of mitochondrial motility revealed ER stress to disrupt mitochondrial motility, while CB showed no significant affect. Initial analysis of fission events showed that following 24-hours of stress, live cell capture of cellular behavior showed no elevation of fission rates in HBE cells. This suggests that changes in mitochondrial numbers may occur at earlier time points. Future work with live cell imaging will assess mitochondrial fission events at different time points. This work reveals chronic CB exposure to impact mitochondrial dynamics in human lung epithelial cells.

Summary of research results to be presented

Cellular incorporation of CB was determined to increase in both a concentration-dependent and time exposure manner, suggesting future studies including more chronic time points. Furthermore, mitochondrial motility (µm/s) does not differ significantly between control and CB200 (200 µg/ml) treated cells, but thapsigargin treatment (200 nM) yields significantly lower mitochondrial motility. Mitochondrial motility at chronic time points will later be assessed to determine if the lack of alteration in motility is due to the nature of CB toxicity or experimental time-exposure. Intracellular impacts of CB were also evident in the significant CB concentration-dependent increases of punctate mitochondria relative to mock (1x BSA/PBS) solution. Moreover, mitochondrial fusion rates were determined to be significantly greater than mitochondrial fission rates in cells treated with CB200 (moderate stress, 200 µg/ml), but fission rates are significantly greater than fusion rates in cells treated with thapsigargin (high stress, 200 nM).

This document is currently not available here.

Share

COinS
 
Nov 18th, 10:00 AM Nov 18th, 11:00 AM

Carbon black nanoparticles disrupt mitochondrial dynamics in human lung cells

BSC-Ursa Minor 62

Carbon black (CB) is the primary nanoparticulate component of environmental pollution from fossil fuel combustion. Prior research has demonstrated that CB induces apoptosis, or programmed cell death, upon accumulation of CB via receptor-mediated endocytosis. The cellular consequences of CB incorporation are not well characterized. Human Bronchial Epithelial cells were used for all analyses described here. In evaluating CB incorporation into cells, we found a dose-dependent accumulation of CB that continues over several days. This identified CB as a stress dependent upon accumulation over time though acute affects have been noted in these studies. CB exposure causes an elevation of reactive oxygen species (ROS) within 8 hours of initial exposure. This result, along with observed abnormalities in mitochondrial dynamics in CB exposed cells garnered interest in mitochondria. CB concentrations ranging as low as 25 µg/ml induce a significant decrease in mitochondrial perinuclear localization at 36 and 48-hour time-points. Small/punctate mitochondrial numbers increased significantly with CB dosage over a period of 24-hours, which is consistent with mitochondrial stress/dysfunction. Live cell imaging of mitochondrial motility revealed ER stress to disrupt mitochondrial motility, while CB showed no significant affect. Initial analysis of fission events showed that following 24-hours of stress, live cell capture of cellular behavior showed no elevation of fission rates in HBE cells. This suggests that changes in mitochondrial numbers may occur at earlier time points. Future work with live cell imaging will assess mitochondrial fission events at different time points. This work reveals chronic CB exposure to impact mitochondrial dynamics in human lung epithelial cells.