M. Kavutcu et al., REDUCED ENZYMATIC ANTIOXIDANT DEFENSE-MECHANISM IN KIDNEY TISSUES FROM GENTAMICIN-TREATED GUINEA-PIGS - EFFECTS OF VITAMIN-E AND VITAMIN-C, Nephron, 72(2), 1996, pp. 269-274
In this study, the activities of major enzymes participating in free r
adical metabolism (xanthine oxidase, XO; Cu,Zn and Mn superoxide dismu
tases, SOD; glutathione peroxidase, GSH-Px; catalase, CAT) were measur
ed in kidney tissues from guinea pigs treated with gentamicin alone (2
00 mg/kg/day), gentamicin plus vitamin C (600 mg/kg/day), gentamicin p
lus vitamin E (400 mg/kg/day), and gentamicin plus vitamins C and E to
gether for 10 days, and from animals treated with physiological saline
solution alone during this period. We found no significant difference
s between control and gentamicin groups with respect to XO and Cu,Zn-S
OD activities. However, the activities of Mn-SOD, GSH-Px, and CAT were
found to be significantly depressed in the gentamicin-treated group r
elative to controls. In the gentamicin plus vitamin C group, the renal
tissue Mn-SOD activity was found to be higher as compared with contro
l and gentamicin groups. In this group, XO, GSH-Px and CAT activities
were also higher than in the gentamicin-treated group, but no statisti
cally significant differences existed between the values of this group
and controls. Similar results were also observed in the gentamicin pl
us vitamin E group for Mn-SOD, GSH-Px, CAT, and XO. In this group, the
Cu,Zn-SOD activity was found to be decreased as compared with control
and gentamicin groups. In the gentamicin plus vitamins C and E group,
the Cu,Zn-SOD activity was found to be decreased, the XO activity to
be unchanged, and Mn-SOD, GSH-Px, and CAT activities to be increased a
s compared with the gentamicin and control groups. The results suggest
that the enzymatic antioxidant defense system was significantly distu
rbed because of the suppressed activities of Mn-SOD, GSH-Px, and CAT i
n the kidney tissues from animals treated with gentamicin. However, vi
tamins C and E given concurrently with gentamicin completely abrogated
this enzymatic suppression.