Abstract
Purpose::
Oxidative stress (OS) has been considered in the mechanism of lacrimal gland (LG) dysfunction in chronic diseases. The present work aim to identify signaling elements related to OS in LG and to compare structural and functional indicators of diabetic damage in LG of rats.
Methods::
Expression of IKK-ß and uncoupling proteins 1, 2 and 3 (UCP) were investigated by Western blot in LG. Diabetes Mellitus (DM) was induced in male Wistar rats with a single intravenous streptozotocin. After 10 weeks, tear secretion was evaluated by modified Schirmer test (ST) under anesthesia and LG were compared by histology and the expression of Acetylcholine (Ach), Peroxidase, Malonaldehyde (MDA) by spectrophotometry.
Results::
IKK-ß and UCPs 1, 2 and 3 were expressed in LG. After 10 weeks, ST was significantly lower in DM. LG expression of peroxidase and MDA were significantly higher in DM (P<0.05) but Ach was similar in both groups. Histological comparison by HE and DAPI revealed that LG structure and acini content but not nuclei were altered in DM.
Conclusions::
Diabetes induces significant alterations in rat LG structure and tear secretion. The difference in MDA and peroxidase levels suggest that OS may be involved in structural and functional alterations in LG of diabetic rats and that would take part in the mechanism of dry eye. Future studies will clarify whether anti-oxidants are benefic for LG in DM.
Keywords: diabetes • lacrimal gland • oxidation/oxidative or free radical damage