Nagler Rafael M, Klein Ifat, Zarzhevsky Nataly, Drigues Noam, Reznick Abraham Z
Department of Oral and Maxillofacial Surgery, Oral Biochemistry Laboratory and Salivary Clinic, Rambam Medical Center, Haifa, Israel.
Free Radic Biol Med. 2002 Feb 1;32(3):268-77. doi: 10.1016/s0891-5849(01)00806-1.
Saliva is armed with various defense mechanisms, such as the immunological and enzymatic defense systems. In addition, saliva has the ability to protect the mucosa against mechanical insults and to promote its healing via the activity of epidermal growth factor. However, another defense mechanism, the antioxidant system, exists in saliva and seems to be of paramount importance. The most interesting finding of the present study was the demonstration of the existence of much higher concentrations of the various salivary molecular and enzymatic antioxidant parameters in the parotid saliva compared with the submandibular/sublingual saliva. For example, peroxidase, superoxide dismutase, uric acid, and total antioxidant status were higher in resting parotid saliva compared with resting submandibular/sublingual saliva by 2405, 235, 245, and 147%, respectively. Another important finding was the distinction between the salivary antioxidant system and the immunological and enzymatic protective systems, as represented by the salivary concentrations of secretory IgA and lysozyme, respectively. These findings suggest that the profound antioxidant capacity of saliva secreted from parotid glands is related either to the different physiological demands related to eating (parotid predominance), to oral integrity maintenance (submandibular/sublingual predominance), or to the high content of deleterious redox-active transitional metal ions present in parotid saliva. This also may signify that our oral cavity environment is only partially protected against oxidative stress during most of the day and night.
唾液具备多种防御机制，如免疫和酶防御系统。此外，唾液能够保护黏膜免受机械损伤，并通过表皮生长因子的活性促进其愈合。然而，唾液中还存在另一种防御机制，即抗氧化系统，它似乎至关重要。本研究最有趣的发现是，与下颌下腺/舌下腺唾液相比，腮腺唾液中各种唾液分子和酶抗氧化参数的浓度要高得多。例如，静息腮腺唾液中的过氧化物酶、超氧化物歧化酶、尿酸和总抗氧化状态分别比静息下颌下腺/舌下腺唾液高2405%、235%、245%和147%。另一个重要发现是唾液抗氧化系统与免疫和酶保护系统之间的区别，分别以唾液中分泌型IgA和溶菌酶的浓度为代表。这些发现表明，腮腺分泌的唾液具有强大的抗氧化能力，这要么与进食相关的不同生理需求（腮腺占主导）、维持口腔完整性（下颌下腺/舌下腺占主导）有关，要么与腮腺唾液中存在的有害氧化还原活性过渡金属离子的高含量有关。这也可能意味着，在白天和夜晚的大部分时间里，我们的口腔环境仅得到部分保护免受氧化应激。
