In vitro antigenotoxic studies of Thai noni fruit juice (Morinda citrifolia L., Rubiacecae) against a chemotherapeutic agent, mitomycin c, in human lymphocytes
Noni fruit (Morinda citrifolia L., Rubiacecae) juice (NFJ) has been widely used in traditional medicine with a broad range of therapeutic effects such as anti-cancer, anti-arthritis and pain-killing. This study aimed to investigate the antigenotoxic activities of NFJ produced in Thailand against a chemotherapeutic drug, mitomycin C (MMC), in human lymphocytes in vitro by sister chromatid exchange (SCE) and chromosomal aberration assays. Pretreatment of Thai NFJ at concentrations of 0.3%-5.0% (v/v) for 2h followed by MMC at 3µg/ml for 2h was evaluated. NFJ pretreatment only at a concentration of 0.3% demonstrated significant decrease in SCE level induced by MMC (p<0.05). However, these treatments did not cause significant reduction in chromatid-type aberrations induced by MMC. In other words, our data indicate that Thai NFJ is not an anticlastogen but has some antigenotoxic effects against MMC as demonstrated by significant decrease in the SCE level (p<0.05). Additionally, pretreatment of the NFJ at higher dosage (≥1.2%) followed by MMC tended to have lower mitotic index (M.I.) and proliferation index (P.I.) when compared to that at lower dosage. However, no significant difference in M.I. and P.I. was observed between the treated group and the MMC treatment alone. This indicates synergistic toxic effect between NFJ at high dose and MMC. Therefore, optimum dosage of NFJ intake in traditional medicine for human safety is strongly required especially when NFJ is in combination with other drugs. Further scientific study is also necessary to clarify the antigenotoxic activities of the NFJ against other genotoxic compounds.
Acknowledgement: This study was supported by Research fund, Thammasat University, Thailand.