Involvement of reactive oxygen species and caspase-dependent pathway in berberine-induced cell cycle arrest and apoptosis in C6 rat glioma cells

Abstract

Abstract. The cytotoxicity of berberine on C6 rat glioma cells indicated that berberine induced morphological changes and caused cell death through G2/M arrest and apoptosis. While undergoing apoptosis, there was a remarkable accumulation of G2/M cells with the upregulatoin of Wee1 but it also inhibited cyclin B, CDK1 and Cdc25c that led to G2/M arrest. Along with cytotoxicity in C6 cells, several apoptotic events including mitochondrial cytochrome c release, activation of caspase-9, -3 and -8 and DNA fragmentation were induced. Berberine increased the levels of GADD153 and GRP 78 in C6 cells based on the examination of Western blotting and this is a major hallmark of endoplasmic reticulum (ER) stress. We also found that berberine promoted the production of reactive oxygen species and Ca 2+ in C6 cells. Western blotting assay also showed that berberine inhibited the levels of anti-apoptotic protein Bcl-2 but increased the levels of pro-apoptotic protein Bax before leading to a decrease in the levels of mitochondrial membrane potential (Δae m ) followed by cytochrome c release that caused the activations of capase-9 and -3 for apoptotic occurrence. The caspase-8, -9 and -3 were activated by berberine in C6 cells based on the substrate solution (PhiPhiLux-G 1 D 1 , CaspaLux 8-L 1 D 2 , CaspaLux 9-M 1 D 2 for caspase-3, -8 and -9, respectively) and analyzed by flow cytometer and each inhibitor of caspase-8, -9 and -3 led to increase the percentage of viable C6 cells after exposure to berberine. This finding was also confirmed by Western blot assay which showed that berberine promoted the active form of caspase-8, -9 and -3. These results demonstrate that the cytotoxicity of berberine in C6 rat glioma cells is attributable to apoptosis mainly through induced G2/M-arrested cells, in an ER-dependent manner, via a mitochondria-dependent caspase pathway regulated by Bax and Bcl-2.

Synthesis and in-vitro anticancer evaluation of polyarsenicals related to the marine sponge derived Arsenicin A

“…It has also been demonstrated that arsenic tetroxide has a greater potential against human cervix, gastric, and head cancer cells when used in combination 6 , e.g. with paclitaxel 7 . Despite the success of arsenic trioxide in the treatment of APL, its efficacy towards solid tumors is limited by its poor pharmacokinetics and dose-limiting toxicity.…”

Determinants and Consequences of Arsenic Metabolism Efficiency among 4,794 Individuals: Demographics, Lifestyle, Genetics, and Toxicity

“…Both pentavalent and trivalent forms of these arsenic species can be present in urine (20,22–25). The trivalent forms of iAs, MMA, and DMA are likely to be the more toxic forms (20,26–29) with MMA III having the highest toxicity followed by iAs III (30,31). Previous studies have shown that iAs%, MMA%, and MMA/iAs are positively associated and DMA%, and DMA/MMA are negatively associated with skin lesions with higher levels of MMA% associated with highest risk of skin lesions (32,33).…”

Efficient Arsenic Metabolism — The AS3MT Haplotype Is Associated with DNA Methylation and Expression of Multiple Genes Around AS3MT

“…In humans, efficient methylation from inorganic arsenic to DMA is associated with a high rate of arsenic excretion in the urine [6]. Incomplete arsenic metabolism, with higher urinary inorganic arsenic and MMA, but lower DMA, seems to be a marker of increased susceptibility to arsenic-related diseases, including cancer [7], [8].…”