Modulatory role of melatonin on superoxide release by spleen macrophages isolated from alloxan-induced diabetic rats.
The aim of this study was to evaluate the modulatory effect of melatonin on superoxide release by spleen macrophages isolated from alloxan-induced diabetic insulin treated or non-treated rats.


METHODS
Blood glucose, body weight, CuZn-superoxide dismutase concentration, and superoxide release by spleen macrophages were evaluated.


RESULTS
The spontaneous superoxide release from the macrophages of the control group was lower when compared to diabetic rats without insulin treatment. Melatonin (MLT) significantly increased the superoxide release in the control group (11.5 +/- 1.5 with MLT x 6.8 +/- 1.0 without MLT). The macrophages from diabetic rats treated with insulin exhibited a decreased superoxide release (7.0 +/- 2.4), when compared to superoxide release of the macrophages from diabetic rats without insulin (14.7 +/- 3.7). CuZn-SOD concentrations were increased in both diabetic groups.


CONCLUSIONS
The pineal hormone melatonin in physiological concentration can stimulate natural immunity since it triggers the superoxide release from the macrophages, an important anti-infectious mechanism. On the other side, melatonin had antioxidant effects in the macrophages from insulin-treated alloxan-induced diabetic rats (Tab. 1, Fig. 2, Ref. 51).
França
Eduardo Luzia
EL
Instituto Universitario do Araguaia, Federal University ofMato Grosso, Pontal do Araguaia, Brazil.
Feliciano
Nagilla Daliane
ND
Silva
Karina Aparecida
KA
Ferrari
Carlos Kusano Bucalen
CK
Honorio-França
Adenilda Cristina
AC
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000378:metabolism*; D066298:In Vitro Techniques; D007328:Insulin / Q000627:therapeutic use; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013154:Spleen / Q000166:cytology*; D013482:Superoxide Dismutase / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism*
D007328:Insulin; D013481:Superoxides; D013482:Superoxide Dismutase; D008550:Melatonin