S-Sulfocysteine's toxic effects on HT-22 cells are not triggered by glutamate receptors, nor do they involve apoptotic or genotoxicity mechanisms

Abstract

S-Sulfocysteine (SSC) is a metabolite derived from the metabolism of sulfur-containing amino acids. It has been implicated in neurotoxicity observed in children with sulfite oxidase deficiency. The aim of our study was to confirm the neurotoxic effects of SSC using a mouse hippocampal cell line (HT-22) and to investigate the role of apoptosis in these effects, especially in terms of caspase-3 activation and genotoxicity. Based on the viability graph obtained following increasing concentrations of SSC, we determined the LC50 dose of SSC to be 125 µM by probit analysis. The cytotoxic effects of SSC were not reversed by glutamate receptor blocker administration. However, SSC treatment did not induce caspase-3 activation or induce DNA damage. Our results showed that SSC has a cytotoxic effect on neurons like glutamate, but glutamate receptor blockers reversed glutamate-induced toxicity, while these blockers did not protect neurons from SSC toxicity. The absence of caspase-3 activation and DNA fragmentation, which are indicative of apoptosis, in SSC-induced cell death suggests that alternative cell death pathways, such as necrosis and oxytosis may be implicated. Further research is necessary to fully elucidate SSC-induced cell death. The aim of our study was to confirm the neurotoxic effects of SSC using a mouse hippocampal cell line (HT-22) and to investigate the role of apoptosis in these effects, especially in terms of caspase-3 activation and genotoxicity.

Keywords: Apoptosis; Cytotoxicity; HT-22 cell; S-Sulphocysteine.