Background: To observe the effect of linear alkylbenzenesulfonate (LAS) on oxidative stress and collagen fiber in skin tissue of mice and to explore the correlation between oxidative stress and collagen metabolism.
Methods: Forty healthy Kunming mice (male) were randomly divided into 4 groups: a control group, a low-, middle- and high-dose group of LAS (LD, MD and HD groups), treated with LAS at 150, 300 and 600 mg/L respectively (n=10 per group). The skin on the back of mice was smeared with distilled water or different dosage of LAS for 60 days. The measured indexes included general condition of mice, HE and Masson staining of skin, the content of hydroxyproline (Hyp) in skin tissue, the activity of super oxidase dismutase (SOD) and the content of malondialdehyde (MDA) in skin tissue and serum, and the activity of lactate dehydrogenase (LDH) in serum.
Results: Compared with the control group, the changes of diet, daily activities and mental state of mice with different dose of LAS were not obvious during the experiment, but the body weight of mice in the experimental groups reduced obviously after 4 weeks of experiment (P<0.01), and their skin tissue was thinner, some of epidermis of skin contained areas with cellular necrosis and abscission. Superficial layer of dermis was infiltrated by inflammatory cells. The collagen fibers were looser and dimmer. At the same time, the content of MDA and the activity of LDH increased remarkably (P<0.01), while the activity of SOD and the content of Hyp decreased obviously (P<0.01).
Conclusions: LAS can induce oxidative stress in the skin tissue of mice, which can destroy the integrity of skin structure and collagen fiber and reduce the content of collagen fiber. The oxidative damage might be the primary cause for disorders of collagen fiber. .
目的：观察直链烷基苯磺酸钠(linear alkylbenzenesulfonate，LAS)对小鼠皮肤组织的氧化应激及胶原纤维的影响，并初步探讨二者之间的关系。方法：将40只健康昆明种雄性小鼠随机分成4组，分别为正常对照组、LAS低剂量组(150 mg/L)、中剂量组(300 mg/L)及高剂量组(600 mg/L)，每组10只。分别用蒸馏水及不同剂量的LAS涂抹各组小鼠的背部剃毛处，每日1次，连续涂抹60 d。观察各组小鼠的饮食、日常活动等一般情况及体质量变化情况；取涂抹部位皮肤进行HE及Masson染色观察皮肤组织结构及胶原纤维变化情况；测定皮肤组织中羟脯氨酸(Hyp)的含量评价胶原蛋白量的变化；检测皮肤匀浆及血清中超氧化物歧化酶(SOD)的活性、丙二醛(MDA)含量及血清中乳酸脱氢酶(LDH)活性评价氧化应激的变化。结果：实验期间，LAS各剂量组小鼠在饮食、日常活动及精神状态方面与正常对照组没有明显差异；4周后，各剂量组小鼠体质量明显低于正常对照组，差异有统计学意义(P<0.01)。HE及Masson染色显示：LAS各剂量组小鼠皮肤明显变薄，表皮细胞部分坏死、脱落，真皮浅表有炎细胞浸润；胶原纤维减少，纤维排列杂乱、松散、模糊。各生化指标显示：与正常对照组相比，LAS各剂量组小鼠MDA含量及LDH活性明显增加(P<0.01)，SOD活性及Hyp含量均明显降低(P<0.01)。结论：LAS能诱导小鼠皮肤组织氧化应激状态；破坏皮肤结构的完整性，使其出现明显的病理改变；使胶原纤维形态发生改变且含量明显减少。氧化应激引起的氧化损伤可能是胶原改变的主要原因。.