Somade Oluwatobi T, Ugbaja Regina N, Adeyi Olubisi E, Ogunberu Damilola M
Department of Biochemistry, College of Biosciences, Federal University of Agriculture Abeokuta, Abeokuta, Nigeria.
Biochim Open. 2016 Sep 28;3:40-46. doi: 10.1016/j.biopen.2016.09.002. eCollection 2016 Dec.
Information on dimethyl nitrosamine (DMN)-induced toxicity on endocrine functions is still scanty. This study therefore investigated the outcomes of DMN-induced toxicity on endocrine (thyroid and reproductive) functions, as well as kallikrein-3 level, and effects of ascorbate treatments in male wistar rats. Thirty animals divided into six groups of five rats each were used. Group I animals were the normal control, group II animals served as vehicle control and were administered a single intraperitoneal dose of normal saline, groups III and IV were intraperitoneally injected with a single dose of 30 mg/kg DMN for 48 h, but group IV animals were post-treated orally with 5.71 mg/kg body weight (400 mg/70 kg) ascorbate for seven days, group V animals were pre-treated with same dose of ascorbate orally for seven days before intraperitoneal injection of DMN, while group VI animals were orally administered ascorbate only for seven days. Compared with control, DMN administration resulted in significant decrease (p < 0.05) in serum total cholesterol, testosterone (TST), luteinizing hormone (LH), free triiodothyronine (fT), and kallikrein III (KLK-3) levels, as well as non-significant increase in serum thyroid stimulating hormone (TSH) level. Pre-treatment with ascorbate significantly increase LH and KLK-3 levels, while post-treatment significantly increase fT level. Also, pre-treatment with ascorbate significantly reduced TSH level, while there was no significant difference in TST level following ascorbate treatments. From our findings and to some extent, ascorbate demonstrates ameliorative effects against DMN-induced hormonal disruption in male wistar rats, and this may be attributed to its antioxidant property.
关于二甲基亚硝胺（DMN）对内分泌功能毒性作用的信息仍然匮乏。因此，本研究调查了DMN诱导的毒性对内分泌（甲状腺和生殖）功能、激肽释放酶-3水平的影响，以及抗坏血酸处理对雄性Wistar大鼠的作用。将30只动物分为6组，每组5只大鼠。第一组动物为正常对照组，第二组动物作为溶剂对照组，腹腔注射单剂量生理盐水，第三组和第四组腹腔注射单剂量30 mg/kg DMN，持续48小时，但第四组动物在注射后口服5.71 mg/kg体重（400 mg/70 kg）抗坏血酸，持续7天，第五组动物在腹腔注射DMN前口服相同剂量抗坏血酸，持续7天，而第六组动物仅口服抗坏血酸，持续7天。与对照组相比，DMN给药导致血清总胆固醇、睾酮（TST）、黄体生成素（LH）、游离三碘甲状腺原氨酸（fT）和激肽释放酶III（KLK-3）水平显著降低（p<0.05），血清促甲状腺激素（TSH）水平无显著升高。抗坏血酸预处理显著提高LH和KLK-3水平，而抗坏血酸后处理显著提高fT水平。此外，抗坏血酸预处理显著降低TSH水平，而抗坏血酸处理后TST水平无显著差异。从我们的研究结果来看，在一定程度上，抗坏血酸对DMN诱导的雄性Wistar大鼠激素紊乱具有改善作用，这可能归因于其抗氧化特性。
