In vivo effects of indomethacin--II. Antioxidant enzymes in metal-deficient rats

In vivo effects of meloxicam, celecoxib, and ibuprofen on free radical metabolism in human erythrocytes

One of the major groups of chemical mediators involved in the inflammatory response is the prostaglandins, which are synthesized from arachidonic acid by the enzyme cyclooxygenase. The aim of this study is to compare the in vivo effects of celecoxib, meloxicam, and ibuprofen on the activities of catalase (CAT), glutathione peroxidase (GSHPx), superoxide dismutase (SOD) as well as malondialdehyde (MDA), and antioxidant potential levels (AOP) in human erythrocytes. Patients diagnosed as osteoarthritis were included in the study. Patients were treated with Celecoxib (200 mg/d) (n = 12), Meloxicam (15 mg/d) (n = 12), and Ibuprufen (1200 mg/d) (n = 9) for 21 days. SOD, CAT, GSHPx activities, MDA, and AOP levels were investigated in human erythrocyte haemolysates. SOD activity and AOP levels were significantly decreased in all NSAID groups when we compared the values before and after 21 days of celecoxib, meloxicam, ibuprofen treatment. There were no significant difference in CAT, GSHPx activities, and MDA levels before and after treatment in each group. Decreased SOD activities are thought to be related with the increased superoxide anion. Decreased AOP levels may indicate impairment in the total antioxidant defence system. These NSAIDs have similar effects on free radical metabolism on human erythrocytes; despite some difference in action mechanisms.

Maternal risk factors in fetal alcohol syndrome: provocative and permissive influences

We present an hypothesis integrating epidemiological, clinical case, and basic biomedical research to explain why only relatively few women who drink alcohol during pregnancy give birth to children with alcohol-related birth defects (ARBDs), in particular, Fetal Alcohol Syndrome (FAS). We argue that specific sociobehavioral risk factors, e.g., low socioeconomic status, are permissive for FAS in that they provide the context for increased vulnerability. We illustrate how these permissive factors are related to biological factors, e.g., decreased antioxidant status, which in conjunction with alcohol, provoke FAS/ARBDs in vulnerable fetuses. We propose an integrative heuristic model hypothesizing that these permissive and provocative factors increase the likelihood of FAS/ARBDs because they potentiate two related mechanisms of alcohol-induced teratogenesis, specifically, maternal/fetal hypoxia and free radical formation.

Do indomethacin and cimetidine or Cu(cimetadine)2 affect the nature of superoxide dismutase activity in the liver of copper-deficient rats?

1. Control and copper-deficient rats were treated with: (i) indomethacin; (ii) indomethacin in the presence of cimetidine; and (iii) indomethacin in the presence of Cu(cimetidine)2. The levels of copper, zinc and manganese as well as the nature of superoxide dismutase activity in the liver were studied. 2. Copper deficiency caused a decrease of enzyme SOD activity, EDTA-insensitive (by 84%) and the appearance of nonenzyme SOD-like activity, EDTA-sensitive. The levels of copper and zinc decreased by 67% and 40% and the manganese level increased by 53%. 3. The above-mentioned treatments (i, ii, iii) of copper-deficient rats induced a progressive increase of enzyme SOD activity (by 19, 90 and 176%, respectively) without, however, changing nonenzyme SOD-like activity. It was only indomethacin treatment in the presence of Cu(cimetidine)2 that increased the copper level in control (by 82%) and copper-deficient (by 182%) rats. 4. The liver contained 4 CuZnSOD- and 1 MnSOD-isoenzymes, whose number and position on the gel were affected neither by copper deficiency nor by indomethacin treatment in the presence of Cu(cimetidine)2. Copper deficiency significantly increased the MnSOD-band and reduced the CuZnSOD-bands, particularly that with pI approximately 5.7. Indomethacin in the presence of Cu(cimetidine)2 changed neither the MnSOD-band nor the reduced CuZnSOD-band with pI approximately 5.7, but restored to normal all the other CuZnSOD-bands.

Liver superoxide dismutases after copper deficiency and/or indomethacin treatment of rats

Copper deficiency in rats resulted in a decrease of liver cytosolic and lysosomal CuZnSOD activity (by 71% and by 55%, respectively) and in an increase of mitochondrial MnSOD (by 185%). The content of copper and zinc decreased by 64% and 38%, respectively, and that of manganese increased by 47%. Cytosolic CuZnSOD activity, both in control and copper-deficient rats, increased (by 71.5 units/mg protein and by 83.0 units/mg protein, respectively) after indomethacin treatment. Rat liver contained four CuZnSOD (cytosolic and lysosomal) and one MnSOD isoenzyme. Neither copper deficiency nor indomethacin treatment changed the position and the number of bands. The CuZnSOD-band with pI approximately 5.7 was greatly decreased by copper deficiency and was not restored to normal after indomethacin treatment.

In vivo effects of indomethacin on the activity of metal-containing enzymes

1. Indomethacin injected subcutaneously at a single "ulcerogenic" dose decreased aminooxidase and leucine aminopeptidase activity and did not change alcohol dehydrogenase and ceruloplasmin activity. 2. Indomethacin administered at an oral "therapeutic" dose inhibited aminooxidase activity in small intestinal mucosa but not in liver and did not change leucine aminopeptidase activity in blood, liver and intestinal mucosa; it, however, increased alcohol dehydrogenase and ceruloplasmin activity. 3. The decreased activity of ceruloplasmin and alcohol dehydrogenase by metal deficiency increased after oral indomethacin treatment, reaching the control values when indomethacin was chelated with copper. 4. The results suggest the participation of endogenous metals in the indomethacin effect.