Effect of streptozotocin on reactive oxygen species and antioxidant enzyme secretion in rat submandibulary glands: a direct and an indirect relationship between enzyme activation and expression.

The salivary glands are important exocrine and endocrine organs, whose role in oral health is well recognized. Also these glands contribute to the maintenance of systemic health. During diabetes an impairment of salivary glands is reported. In this work the oxidative stress produced after 10days of a single dose of streptozotocin administration in rats was observed in submandibulary glands. Under this condition a misbalance of the enzymes with antioxidant activity was observed in glands and in incubation medium, as well as in reactive oxygen species such as hydrogen peroxide (H(2)O(2)), superoxide anion (O(2)(-)) and nitric oxide (NO). An increase of NO and H(2)O(2) and a decrease of O(2)(-) were found. A direct relationship between peroxidase and nitric oxide synthase (iNOS) activities with enzyme expression was recorded, in contrast an inverse relationship between superoxide dismutase activity and expression was observed. If the high level of H(2)O(2) persists in time as well as a low level of peroxidase, oral pathologies are expected to occur. So, under this situation to study the modulation of enzymes involved in reactive oxygen species metabolism during oxidative stress in oral tissues could be very important in the managing of oral pathologies.