Genotoxicity-suppressing effect of aqueous extract of Connarus ruber cortex on cigarette smoke-induced micronuclei in mouse peripheral erythrocytes

Abstract

IntroductionAccording to published information, it has not been determined whether the inhalation of cigarette smoke can induce chromosome aberrations and/or point mutations in mice, though cigarette smoke is clearly carcinogenic to mice. We tested clastogenicity of inhaled cigarette smoke in mouse by a micronucleus test using peripheral erythrocytes. Since it is important to determine the in vivo anti-genotoxic effect against inhaled cigarette smoke to reduce the risk of tobacco carcinogenesis, we also tested in vivo anti-gnotoxic effect against inhaled cigarette smoke of a Connarus extract whose in vitro anti-genotoxic effect was shown.ResultsMale ICR mice were exposed for 1 min to a 6-fold dilution of the smoke once a day for up to 14 consecutive days. Although the frequencies of reticulocytes with micronucleus (MNRETs) and erythrocytes with micronuclei (MN erythrocytes) did not increase within 72 h after a single inhalation of cigarette smoke, the frequency of MN erythrocytes increased significantly upon inhalation for 7 and 14 days. When the Connarus extract was fed to mice at >23.7 ppm during the inhalation period of 14 days, frequency of MN erythrocytes was significantly lower than that at 0 ppm. In vitro antioxidant activity of Connarus extract was almost same to that of vitamin C. The antioxidant activity of the Connarus extract might play an important role in its anti-genotoxic effect against cigarette smoke in vivo, like vitamins C.ConclusionsConsecutive inhalation of cigarette smoke is clastogenic to mouse bone marrow as shown by the increased frequency of MN erythrocytes. Also, it was shown the possibility that the Connarus extract reduces the risk of tobacco carcinogenesis.

Assessment of the Potential Genotoxicity and Cardiac Teratogenicity of Venlafaxine on Embryos of Pregnant Black Mice

“…The non-significant difference between the number of micronucleated immature erythrocytes in the bone marrow and the number of micronucleated erythrocytes in peripheral blood sample at GD 18 is explained by the theory stating that the spleen in mice does not remove micronucleated erythrocytes [43] .…”

In Vitro and In Vivo Antiglycation Effects of Connarus ruber Extract

“…C. ruber has been used as a folk remedy for several diseases, including diabetes in South America, and its extract is consumed as herbal tea. Previously, we reported that its extract decreased the level of DNA damage in the white blood cells of smokers [16] and prevented the induction of insulin resistance [17]. However, the underlying mechanism has not yet been elucidated.…”