Universidade de Franca, Franca, São Paulo, Brazil.
Mutat Res. 2012 Dec 12;749(1-2):87-92. doi: 10.1016/j.mrgentox.2012.09.001. Epub 2012 Sep 7.
The pimarane-type diterpene, pimaradienoic acid (PA), is known for its diverse biological properties such as antimicrobial, anti-inflammatory and trypanocidal. A preliminary study was undertaken to investigate in vitro the free radical-scavenging potential of PA. In addition, the genotoxic potential of PA and its ability to modulate genotoxicity induced by doxorubicin (DXR) and methyl methanesulfonate (MMS) were studied in Chinese hamster lung fibroblasts (V79 cells) and in male Swiss mice using the comet and micronucleus assays. The DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) assay showed that PA exerted no antioxidant activity when compared to quercetin. The colony-forming assay using V79 cells showed that PA was cytotoxic at concentrations >5.0μg/mL. Therefore, concentrations of 0.625, 1.25, 2.5, and 5.0μg/mL were used for evaluation of the genotoxic and antigenotoxic potential of PA in V79 cells. For genotoxic and antigenotoxic assessment in Swiss mice, three PA doses were tested (20, 40, and 80mg/kg body weight) based on the solubility limit of the diterpene in dimethylsulfoxide and water. The in vitro results demonstrated that PA induced DNA damage at concentrations of 2.5 and 5.0μg/mL in the comet assay. However, no genotoxic effect was observed in the micronucleus test using V79 cells. In the in vivo evaluation of genotoxicity, a significant increase in the frequency of DNA damage was observed in hepatocytes of animals treated with the highest PA dose (80mg/kg) when compared to the control group, but this difference was not seen in the micronucleus test. Furthermore, PA significantly reduced the frequency of DXR- and MMS-induced micronuclei and extent of DNA damage in in vitro and in vivo test systems.
pimaradienoic 酸（PA）是一种松香烷型二萜，具有多种生物特性，如抗菌、抗炎和杀锥虫作用。本研究旨在初步探讨 PA 的体外自由基清除能力。此外，还研究了 PA 的遗传毒性及其对阿霉素（DXR）和甲基甲磺酸（MMS）诱导遗传毒性的调节作用，采用彗星和微核试验，在中国仓鼠肺成纤维细胞（V79 细胞）和雄性瑞士小鼠中进行。DPPH（2,2-二苯基-1-苦基肼水合物）试验表明，与槲皮素相比，PA 没有抗氧化活性。V79 细胞集落形成试验表明，PA 在浓度>5.0μg/mL 时具有细胞毒性。因此，采用 0.625、1.25、2.5 和 5.0μg/mL 浓度评估 PA 在 V79 细胞中的遗传毒性和抗原毒性。对于瑞士小鼠的遗传毒性和抗原毒性评估，基于二萜在二甲基亚砜和水中的溶解度极限，测试了 3 种 PA 剂量（20、40 和 80mg/kg 体重）。体外试验结果表明，PA 在彗星试验中在 2.5 和 5.0μg/mL 浓度下诱导 DNA 损伤。然而，在 V79 细胞的微核试验中未观察到遗传毒性作用。在体内遗传毒性评价中，与对照组相比，最高 PA 剂量（80mg/kg）处理的动物肝细胞中 DNA 损伤频率显著增加，但在微核试验中未观察到这种差异。此外，PA 显著降低了体外和体内试验系统中 DXR 和 MMS 诱导的微核和 DNA 损伤的频率。
