Abstract: Objective To investigate the effects of almonds on DNA damaged peripheral blood lymphocytes in rats induced by H₂O₂.Methods 5.0 g almonds were ground into homogenate and diluted to 100 mL with redistilled water. Respectively extracted the homogenate 1.0, 2.0 and 3.0 mL then diluted them to 10 mL with redistilled water. The concentrations of almonds were 5.0, 10.0 and 15.0 g/L respectively. RPMI 1640 was used to separate the lymphocyte from 1 mL whole blood of a SD rat and adjusted the lymphocyte density to 1×10⁹/L. The lymphocytes were separated into 5 groups: ① control group; ② H₂O₂ group; ③ low dosage group: H₂O₂+50 mg/L almond; ④ moderate dosage group: H₂O₂+100 mg/L almond; ⑤ high dosage group: H₂O₂+150 mg/L almond. Except for control and H₂O₂ groups, different dosages of almonds(the final concentrations were 50, 100 and 150 mg/L) were added to the other groups. The lymphocytes of 5 groups were cultured in CO₂ incubator for 24 hours. Except for control group, H₂O₂(the final concentration was 50 μmol/L) was added to the other groups. PBS was used to rinse the lymphocytes of every group twice. Using trypsinase to digest the lymphocytes of every group for 1 minute, then blew the lymphocytes gently with sucker and adjusted the lymphocyte density to (1～10)10/L. The lymphocyte density was again adjusted to 109/L with agarose gel. DNA damaged peripheral blood lymphocytes of rats was measured by single-cell gel electrophoresis (SCGE) and laser scanning confocal microscopy. Taking two pictures of each group and observing 100 lymphocytes in each picture randomly. The number of DNA damaged peripheral blood lymphocytes of rats was counted and the tail length of comet measured. The data of the tail length of comets were treated with one-way ANOVA and the rates of DNA damaged peripheral blood lymphocytes were treated with Chi-Square test.Results The rates of DNA damage in control group, H₂O₂ group, low dosage group, moderate dosage group and high dosage group were 22.5%, 68.5%, 52.5%, 37.5% and 35% respectively. The tail length in control group, the H₂O₂ group, the low dosage group, moderate dosage group and high dosage group were (16.25±1.52)μm, (35.86±1.75)μm, (29.63±2.03)μm, (23.58±1.37)μm and (23.49±1.63)μm respectively. Compared with the control group, DNA damaged peripheral blood lymphocytes of rat in other groups increased remarkably(P<0.05). Compared with H₂O₂ group, DNA damage reduced notably when the doses of almond increased and it showed a dose-effect relationship(P<0.05).Conclusion It is indicative that almonds have effects of anti-oxidation to a certain extent.

Key words: almonds, lymphocytes, single-cell gel electrophoresis, DNA