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N-acetyl cysteine mitigates the acute effects of cocaine-induced toxicity in astroglia-like cells.

Badisa RB, Kumar SS, Mazzio E, Haughbrook RD, Allen JR, Davidson MW, Fitch-Pye CA, Goodman CB - PLoS ONE (2015)

Bottom Line: Of all cells within the CNS, astrocytes may be the first to display cocaine toxicity owing to their relative abundance in the brain.We show further that this alleviation by NAC is mediated through an increase in GSH levels in the cells.These findings, coupled with the fact that astrocytes maintain neuronal integrity, suggest that compounds which target and mitigate these early toxic changes in astrocytes could have a potentially broad therapeutic role in cocaine-induced CNS damage.

View Article: PubMed Central - PubMed

Affiliation: College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, United States of America.

ABSTRACT
Cocaine has a short half-life of only about an hour but its effects, predominantly on the central nervous system (CNS), are fairly long-lasting. Of all cells within the CNS, astrocytes may be the first to display cocaine toxicity owing to their relative abundance in the brain. Cocaine entry could trigger several early response changes that adversely affect their survival, and inhibiting these changes could conversely increase their rate of survival. In order to identify these changes and the minimal concentrations of cocaine that can elicit them in vitro, rat C6 astroglia-like cells were treated with cocaine (2-4 mM for 1h) and assayed for alterations in gross cell morphology, cytoplasmic vacuolation, viability, reactive oxygen species (ROS) generation, glutathione (GSH) levels, cell membrane integrity, F-actin cytoskeleton, and histone methylation. We report here that all of the above identified features are significantly altered by cocaine, and may collectively represent the key pathology underlying acute toxicity-mediated death of astroglia-like cells. Pretreatment of the cells with the clinically available antioxidant N-acetyl cysteine (NAC, 5 mM for 30 min) inhibited these changes during subsequent application of cocaine and mitigated cocaine-induced toxicity. Despite repeated cocaine exposure, NAC pretreated cells remained highly viable and post NAC treatment also increased viability of cocaine treated cells to a smaller yet significant level. We show further that this alleviation by NAC is mediated through an increase in GSH levels in the cells. These findings, coupled with the fact that astrocytes maintain neuronal integrity, suggest that compounds which target and mitigate these early toxic changes in astrocytes could have a potentially broad therapeutic role in cocaine-induced CNS damage.

No MeSH data available.


Related in: MedlinePlus

Gross morphological features of astroglia-like cells in culture during acute exposure to cocaine.Cells were treated with PBS (control) (A) and 2–4 mM cocaine (B-D) for 1h. Optical images are of crystal violet stained cells taken with an inverted phase contrast IX-70 Olympus microscope with a 40x objective. Note the conspicuous cocaine-induced vacuoles in the cytoplasm (B-D). Scale bar: 50 μm.
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pone.0114285.g002: Gross morphological features of astroglia-like cells in culture during acute exposure to cocaine.Cells were treated with PBS (control) (A) and 2–4 mM cocaine (B-D) for 1h. Optical images are of crystal violet stained cells taken with an inverted phase contrast IX-70 Olympus microscope with a 40x objective. Note the conspicuous cocaine-induced vacuoles in the cytoplasm (B-D). Scale bar: 50 μm.

Mentions: One of the first and foremost effects of toxic drug exposure is a change in cell morphology. Microscopic observation of crystal violet stained astroglia-like cells revealed that an hour-long exposure to cocaine was enough to evoke profound alterations in general architecture including cell-shape. The whole cell morphology became irregular, intercellular gaps expanded and there was a marked vacuolization as a function of cocaine concentration (Fig. 2B-D). Despite these changes, there was no apparent evidence of nuclear lysis at any of the cocaine doses used. As changes in cell morphology are indicative of cell toxicity, it is evident that astroglia-like cells are extremely sensitive to acute exposure of cocaine.


N-acetyl cysteine mitigates the acute effects of cocaine-induced toxicity in astroglia-like cells.

Badisa RB, Kumar SS, Mazzio E, Haughbrook RD, Allen JR, Davidson MW, Fitch-Pye CA, Goodman CB - PLoS ONE (2015)

Gross morphological features of astroglia-like cells in culture during acute exposure to cocaine.Cells were treated with PBS (control) (A) and 2–4 mM cocaine (B-D) for 1h. Optical images are of crystal violet stained cells taken with an inverted phase contrast IX-70 Olympus microscope with a 40x objective. Note the conspicuous cocaine-induced vacuoles in the cytoplasm (B-D). Scale bar: 50 μm.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4305286&req=5

pone.0114285.g002: Gross morphological features of astroglia-like cells in culture during acute exposure to cocaine.Cells were treated with PBS (control) (A) and 2–4 mM cocaine (B-D) for 1h. Optical images are of crystal violet stained cells taken with an inverted phase contrast IX-70 Olympus microscope with a 40x objective. Note the conspicuous cocaine-induced vacuoles in the cytoplasm (B-D). Scale bar: 50 μm.
Mentions: One of the first and foremost effects of toxic drug exposure is a change in cell morphology. Microscopic observation of crystal violet stained astroglia-like cells revealed that an hour-long exposure to cocaine was enough to evoke profound alterations in general architecture including cell-shape. The whole cell morphology became irregular, intercellular gaps expanded and there was a marked vacuolization as a function of cocaine concentration (Fig. 2B-D). Despite these changes, there was no apparent evidence of nuclear lysis at any of the cocaine doses used. As changes in cell morphology are indicative of cell toxicity, it is evident that astroglia-like cells are extremely sensitive to acute exposure of cocaine.

Bottom Line: Of all cells within the CNS, astrocytes may be the first to display cocaine toxicity owing to their relative abundance in the brain.We show further that this alleviation by NAC is mediated through an increase in GSH levels in the cells.These findings, coupled with the fact that astrocytes maintain neuronal integrity, suggest that compounds which target and mitigate these early toxic changes in astrocytes could have a potentially broad therapeutic role in cocaine-induced CNS damage.

View Article: PubMed Central - PubMed

Affiliation: College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, United States of America.

ABSTRACT
Cocaine has a short half-life of only about an hour but its effects, predominantly on the central nervous system (CNS), are fairly long-lasting. Of all cells within the CNS, astrocytes may be the first to display cocaine toxicity owing to their relative abundance in the brain. Cocaine entry could trigger several early response changes that adversely affect their survival, and inhibiting these changes could conversely increase their rate of survival. In order to identify these changes and the minimal concentrations of cocaine that can elicit them in vitro, rat C6 astroglia-like cells were treated with cocaine (2-4 mM for 1h) and assayed for alterations in gross cell morphology, cytoplasmic vacuolation, viability, reactive oxygen species (ROS) generation, glutathione (GSH) levels, cell membrane integrity, F-actin cytoskeleton, and histone methylation. We report here that all of the above identified features are significantly altered by cocaine, and may collectively represent the key pathology underlying acute toxicity-mediated death of astroglia-like cells. Pretreatment of the cells with the clinically available antioxidant N-acetyl cysteine (NAC, 5 mM for 30 min) inhibited these changes during subsequent application of cocaine and mitigated cocaine-induced toxicity. Despite repeated cocaine exposure, NAC pretreated cells remained highly viable and post NAC treatment also increased viability of cocaine treated cells to a smaller yet significant level. We show further that this alleviation by NAC is mediated through an increase in GSH levels in the cells. These findings, coupled with the fact that astrocytes maintain neuronal integrity, suggest that compounds which target and mitigate these early toxic changes in astrocytes could have a potentially broad therapeutic role in cocaine-induced CNS damage.

No MeSH data available.


Related in: MedlinePlus