Planta Med 2013; 79 - PN88
DOI: 10.1055/s-0033-1352430

Genotoxic and antigenotoxic activities of washed water extracts from brown jasmine 105 Thai rice cultivar in human lymphocytes in vitro

T Ratanavalachai 1, S Tanuchit 2, S Thitiorul 3, N Lerdvuthisopon 1, C Jansom 2
  • 1Preclinical Science Department (Biochemistry), Faculty of Medicine, Thammasat University, Paholyothin Rd, A. Klong Luang, Pathumthani, 12121, Thailand.
  • 2Research center, Faculty of Medicine, Thammasat University, Paholyothin Rd, A. Klong Luang, Pathumthani, 12121, Thailand.
  • 3Preclinical Science Department (Anatomy), Faculty of Medicine, Thammasat University, Paholyothin Rd, A. Klong Luang, Pathumthani, 12121, Thailand.

The chemopreventive potential of rice extracts against various cancer, such as breast, liver and colorectal cancer, has been increasingly stated in many reports (1,2). Their mechanisms of action are still unclear. One possible mechanism might be their antigenotoxicity. This study aims to investigate the genotoxic and antigenotoxic activities of washed water extracts from brown jasmine 105 Thai rice (WWBJR) cultivar in human lymphocytes by comet assay in vitro. The washed water from rice is commonly used in Thai traditional medicine especially for anti-inflammation, aphthous ulcer and as aqueous adjuvant. Treatments of WWBJR extract (rice:water 1:2; yield 0.3 g/kg) at the concentrations of 0.7, 7, 70, 700, 7000 ng/µl alone with isolated human lynphocytes (40,000 cells/µl) for 5 min were performed for genotoxic study. For antigenotoxicity, lymphocytes were treated with WWBJR at the same concentrations for 5 min, washed, and then treated with doxorubicin (Drb; a genotoxic chemotherapeutic agent) (0.1 µg/ml) for 5 min. Isolated lymphocytes alone and PBS-treated lymphocytes were used as negative controls whereas Drb (0.1 µg/ml) and hydrogen peroxide (294 mM) were used as positive controls. The results indicated that the WWBJR at all concentration tested could protect cells from genotoxic damage induced by Drb while WWBJR alone did not induce DNA damage above that of the negative controls. Instead, WWBJR at 70 ng/µl or more could significantly decrease DNA damage below that of the control (p < 0.05). Therefore, these WWBJR extracts should be beneficial for chemoprevention. In vivo study of these extracts are needed for further investigation in detail.

Acknowledgements: This study was supported by Research Fund, National Research Council of Thailand (NRCT)

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