Koul Ashwani, Mukherjee Nupur, Gangar Subhash Chander
Department of Biophysics, Basic Medical Sciences Block, Panjab University, Chandigarh, India.
Mol Cell Biochem. 2006 Feb;283(1-2):47-55. doi: 10.1007/s11010-006-2269-7.
Male Balb/c mice were divided into four groups on the basis of their respective treatments wherein mice of Group I served as controls. For induction of skin tumors, mice of Group II and IV were injected sub-cutaneously with 7,12-dimethylbenz(a)anthracene (DMBA). Mice of Group III and IV were administered aqueous Azadirachta indica leaf extract (AAILE) thrice a week throughout the experiment. After 14 weeks of the first DMBA injection, Group II and IV mice developed tumors. In the tumor-bearing mice that received AAILE (Group IV), a significant reduction in mean tumor burden and tumor volume was observed. The tumors were confirmed to be papillomas and interestingly, the extent of hyper-chromatia was observed to be much more in skin tumors of Group II mice vis a vis the mice receiving AAILE. An increase in the extent of lipid peroxidation was observed in tumorous tissue of Group IV when compared to that of Group II mice. Glutathione (GSH) content and the activities of GSH-based antioxidant enzymes viz. glutathione peroxidase (GPx) and glutathione reductase (GR) increased significantly in the skin tissues of all the groups of mice when compared to control counterparts. Catalase activity was found to decrease significantly in the skin of mice, which received AAILE treatment only (Group III). Activity of super-oxide dismutase (SOD) decreased significantly in all the tumorous tissues (Group II and IV mice). In light of the above observations, the role of AAILE in inhibition of DMBA-induced skin carcinogenesis is discussed in the present study.
雄性Balb/c小鼠根据各自的处理方式分为四组，其中第一组小鼠作为对照。为了诱导皮肤肿瘤，第二组和第四组小鼠皮下注射7,12-二甲基苯并(a)蒽（DMBA）。在整个实验过程中，第三组和第四组小鼠每周三次给予印度楝树叶水提取物（AAILE）。在首次注射DMBA 14周后，第二组和第四组小鼠出现肿瘤。在接受AAILE的荷瘤小鼠（第四组）中，观察到平均肿瘤负荷和肿瘤体积显著降低。肿瘤被确认为乳头状瘤，有趣的是，与接受AAILE的小鼠相比，第二组小鼠皮肤肿瘤中的染色质增多程度更高。与第二组小鼠相比，第四组肿瘤组织中的脂质过氧化程度增加。与对照小鼠相比，所有组小鼠皮肤组织中的谷胱甘肽（GSH）含量以及基于GSH的抗氧化酶即谷胱甘肽过氧化物酶（GPx）和谷胱甘肽还原酶（GR）的活性显著增加。仅接受AAILE处理的小鼠（第三组）皮肤中的过氧化氢酶活性显著降低。所有肿瘤组织（第二组和第四组小鼠）中的超氧化物歧化酶（SOD）活性显著降低。鉴于上述观察结果，本研究讨论了AAILE在抑制DMBA诱导的皮肤癌发生中的作用。
