Betaine chloride (Betaine hydrochloride) is an acidic form of betaine, a vitamin-like substance observed in grains and other foods; gains the amplification of DNA by decreasing the formation of secondary structure in GC-rich regions.

Exposure to increasing levels of Betaine hydrochloride significantly inhibits HeLa cell proliferation, as demonstrated by the MTT assay (p<0.05). The S phase cell percentage is notably higher in groups exposed to doses below 5 mg/mL compared to those subjected to higher doses, whereas Sub-G1 phase rates exhibit the reverse trend (p<0.05). Concentrations of Betaine hydrochloride above 5.0 mg/mL markedly induce apoptosis in HeLa cells (p<0.01). Superoxide dismutase (SOD) activity in low dose groups slightly exceeds that of the control group (p<0.05). Additionally, there's a noticeable synchrony and correlation in the expression levels of pro-apoptotic genes (Bax, P53, Caspase 3) and the anti-apoptotic gene (Bcl-2). Furthermore, upon inducing apoptosis signals, p53 and cyclin D1 are activated, potentially halting the cell cycle at either the G1/S or S/G2 checkpoints.