Acrylonitrile induced apoptosis via oxidative stress in neuroblastoma SH‐SY5Y cell

Abstract

Acrylonitrile (ACN) is a chemical that is widely used in the production of plastics, acrylic fibers, synthetic rubbers and resins. It has been reported that ACN can cause oxidative stress, a condition which is well recognized as an apoptotic initiator; however, information regarding ACN-induced apoptosis is limited. This present study investigated whether ACN induces apoptosis in human neuroblastoma SH-SY5Y cells, and whether its apoptotic induction involves oxidative stress. The results showed that ACN caused activation of caspase-3, a key enzyme involved in apoptosis, in a dose- and time-dependent manner. Detection of sub-G1 apoptotic cell death and apoptotic nuclear condensation revealed that ACN caused an increase in the number of apoptotic cells indicating ACN induces apoptosis in SH-SY5Y cells. ACN dose- and time-dependently increased the level of proapoptotic protein, Bax. Pretreatment with N-acetylcysteine (NAC), an antioxidant, attenuated caspase-3 activation by ACN, as evidenced by a reduction in proteolysis of PARP, a known caspase-3 substrate, as well as in the number of sub-G1 apoptotic cells. Moreover, induction of Bax by ACN was abolished by NAC. Taken together, the results indicate that ACN induces apoptosis in SH-SY5Y cells via a mechanism involving generation of oxidative stress-mediated Bax induction.

Differential response to acrylonitrile toxicity in rat primary astrocytes and microglia

“…ACN has been shown to cause oxidative stress in rat brain, neuronal cell lines, and primary glial cultures, with increased oxidative DNA damage and GSH depletion (Kamendulis et al, 1999a; Pu et al, 2006; Watcharasit et al, 2010). F 2 -isoprostanes are generated from the process of free-radical peroxidation of arachidonic acid (AA) and are long lived markers of oxidative stress (Milne et al, 2005).…”

“…1). ACN is cytotoxic in neuronal cell lines, causing an activation of Bax and induction of apoptosis (Watcharasit et al, 2010). Jacob and Ahmed found significant cell death in primary normal human astrocytes treated with 200 and 400 μM ACN, while Pu et al have observed 1 mM ACN to be a sublethal exposure in primary human astrocytes (Jacob and Ahmed, 2003; Pu et al, in preparation).…”

“…Several studies have noted an increase in ROS production in neuronal and astrocytic cell lines following ACN treatment (Jacob and Ahmed, 2003; Kamendulis et al, 1999a; Watcharasit et al, 2010). ACN has also been shown to inhibit the activities of antioxidant enzymes, such as superoxide dismutase (SOD) and catalase, contributing to the increased oxidizing environment (Guangwei et al, 2010; Kamendulis et al, 1999a; Zhang et al, 2002).…”

“…Stimulation of hepatic CYP2E1 activity with agonists has shown increased cyanide production and inhibition of cytochrome c oxidase (Complex IV) in rat brains (Suhua et al, 2010). Increased ACN-induced oxidative stress has also been linked with cell death and dysfunction, as well as Bax mediated apoptosis in the SH-SH5Y cell line (Watcharasit et al, 2010). Treatment of rats or cells with the antioxidants curcumin, α-tocopherol, epigallocatechin gallate (EGCG), or N-acetyl- L-cysteine (NAC) efficiently attenuates ACN-induced oxidative damage, providing further evidence that ACN toxicity is primarily mediated through increased oxidative stress (Esmat et al, 2007; Guangwei et al, 2010; Zhang et al, 2000).…”

Differential protection of pre- versus post-treatment with curcumin, Trolox, and N -acetylcysteine against acrylonitrile-induced cytotoxicity in primary rat astrocytes

“…The M a n u s c r i p t 6 concentrations of antioxidants and AN (detailed below) were based on our pilot experiments. These concentrations were also selected based on the calculation by Chantara et al (2006) and Watcharasit et al (2010), which are relevant to human or animal exposures to AN (Major et al, 1998;Sweeney et al, 2003). Primary astrocytes at 80% confluence were treated with the three antioxidants according to the following protocols:…”