Diode laser decreases the activity of catalase on submandibular glands of diabetic rats.
OBJECTIVE
The aim of this study was to evaluate the effect of laser irradiation on the amylase and the antioxidant enzyme activities, as well as on the total protein concentration of submandibular glands (SMG) of diabetic and non-diabetic rats.


BACKGROUND
Laser has been used aiming to improve some biochemical alterations observed in salivary glands of streptozotocin-induced diabetic rats.


METHODS
Ninety-six female rats were divided into eight groups: D0, D5, D10, and D20 (diabetic animals), and C0, C5, C10, and C20 (non-diabetic animals), respectively. Diabetes was induced by administering streptozotocin and confirmed later by the glycemia results. Twenty-nine days after diabetes induction, the SMG of groups D5 and C5, D10 and C10, and D20 and C20 were irradiated with 5, 10, and 20 J/cm(2), respectively. A diode laser (660 nm/100 mW) was used. On the day after irradiation, the rats were euthanized and the SMG were removed. Catalase, peroxidase, and amylase activities, as well as protein concentration, were assayed.


RESULTS
Diabetic rats without irradiation (D0) showed higher catalase activity (p < 0.05) when compared to C0 (0.16 +/- 0.05 and 0.07 +/- 0.01 U/mg protein, respectively). However, laser irradiation of 5, 10, and 20 J/cm(2) reduced the catalase activity of diabetic groups (D5 and D20) to non-diabetic values (p > 0.05).


CONCLUSIONS
Based on the results of this study, laser irradiation decreased catalase activity in diabetic rats' SMG.
Division of Oral Biology, Dental Materials Department, Faculty of Dentistry, University of São Paulo, São Paulo, Brazil. lysimoes@usp.br
Alyne
A
Simões
Fernando Neves
FN
Nogueira
Carlos
C
de Paula Eduardo
José
J
Nicolau
D000681:Amylases / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D002374:Catalase / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000201:enzymology*; D005260:Female; D054023:Lasers, Semiconductor; D009195:Peroxidase / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D051381:Rats; D013363:Submandibular Gland / Q000201:enzymology* / Q000528:radiation effects*
D011506:Proteins; D002374:Catalase; D009195:Peroxidase; D000681:Amylases