Universidade de Franca, Franca, São Paulo, Brazil.
Universidade Federal de Alfenas, Alfenas, Minas Gerais, Brazil.
J Toxicol Environ Health A. 2021 Jul 18;84(14):582-592. doi: 10.1080/15287394.2021.1910090. Epub 2021 Apr 7.
Pohl, a typical species from the Brazilian cerrado, commonly known as "benjoeiro", is used to treat gastroduodenal diseases. In previous studies carried out by our research group, hydroalcoholic extract of stems (SCHE) exhibited antigenotoxic and antiproliferative effects. For a comparative analysis of the chemopreventive effect of SCHE, the aim of this study was to investigate the influence of SCHE against carcinogen 1,2-dimethylhydrazine (DMH)-induced DNA damage and pre-neoplastic lesions in Wistar rat colon. Animals were treated orally with SCHE at 250, 500 or 1000 mg/kg body weight in conjunction with a subcutaneous injection of DMH. DNA damage was assessed using the comet assay while tpre-neoplastic lesions by aberrant crypt foci (ACF) assay. The following hepatic oxidative stress markers were determined including activities of catalase (CAT) and glutathione S-transferase (GST) as well as levels of reduced glutathione (GSH) and malondialdehyde (MDA). Treatment with SCHE was not genotoxic or carcinogenic at the highest dose tested (1000 mg/kg b.w.). The extract effectively inhibited DNA damage and pre-neoplastic lesions induced by DMH administration at all concentrations tested. Measurement of CAT, and GST activities and levels of GSH showed that SCHE did not reduce oxidative processes. In contrast, treatment with SCHE (1000 mg/kg b.w.) decreased liver MDA levels. Taken together, these findings suggested the chemopreventive effect attributed to SCHE in colon carcinogenesis, may be related to its capacity to inhibit DNA damage as well as an antioxidant action associated with its chemical constituents egonol and homoegonol.
波，一种来自巴西塞拉多的典型物种，通常被称为“benjoeiro”，用于治疗胃十二指肠疾病。在我们研究小组进行的先前研究中，茎的水醇提取物（SCHE）表现出抗原毒性和抗增殖作用。为了比较 SCHE 的化学预防作用，本研究旨在研究 SCHE 对致癌物 1,2-二甲基肼（DMH）诱导的 Wistar 大鼠结肠 DNA 损伤和前肿瘤病变的影响。动物经口给予 SCHE 250、500 或 1000mg/kg 体重，并皮下注射 DMH。使用彗星试验评估 DNA 损伤，并用异常隐窝焦点（ACF）试验评估前肿瘤病变。测定以下肝氧化应激标志物：过氧化氢酶（CAT）和谷胱甘肽 S-转移酶（GST）的活性以及还原型谷胱甘肽（GSH）和丙二醛（MDA）的水平。在最高测试剂量（1000mg/kg b.w.）下，SCHE 既没有遗传毒性也没有致癌性。该提取物在所有测试浓度下均有效抑制 DMH 给药引起的 DNA 损伤和前肿瘤病变。CAT 和 GST 活性以及 GSH 水平的测量表明，SCHE 不会减少氧化过程。相反，SCHE（1000mg/kg b.w.）治疗降低了肝脏 MDA 水平。综上所述，这些发现表明 SCHE 在结肠癌变中的化学预防作用可能与其抑制 DNA 损伤的能力以及与其化学成分 egonol 和 homoegonol 相关的抗氧化作用有关。
