Astrocyte activation: a key step in rotenone induced cytotoxicity and DNA damage

Area of Science:

• Neuroscience
• Toxicology
• Cell Biology

Background:

• Astrocytes, the most abundant glial cells, are crucial for neuronal metabolic support.
• Rotenone, a natural pesticide, is known to inhibit mitochondrial complex-I and exhibit neurotoxicity.
• C6 glioma cells, derived from rat glioma, serve as an astrocyte-like cell model.

Purpose of the Study:

• To investigate the toxic effects of rotenone on C6 astrocyte-like cells.
• To evaluate rotenone-induced cell survival changes, free radical generation, and DNA damage.
• To assess the protective role of melatonin against rotenone toxicity in these cells.

Main Methods:

• C6 cells were treated with varying concentrations of rotenone (0.1, 1, 10 μM).
• Assays included MTT reduction, PI uptake, ROS/RNS measurement, comet assay, and Hoechst staining.
• Glial fibrillary acidic protein (GFAP) and caspase-3 expression were analyzed to evaluate glial activation and apoptosis.

Main Results:

• Rotenone treatment decreased cell survival and increased reactive oxygen and nitrogen species (ROS/RNS) generation.
• DNA damage and altered nuclear morphology were observed following rotenone exposure.
• Rotenone elevated GFAP and caspase-3 levels, indicating glial activation and apoptosis.

Conclusions:

• Rotenone induces significant toxicity in C6 astrocyte-like cells, characterized by reduced survival, increased oxidative stress, and DNA damage.
• Melatonin, an antioxidant, effectively mitigated rotenone-induced cellular damage and apoptosis.
• These findings highlight the critical role of free radicals in rotenone-induced astrocyte activation and toxicity, suggesting potential therapeutic targets.