Oxidative stress parameters as markers of the different trimesters in normal pregnancy

Pregnancy has been associated with changes in physiologic and metabolic functions accompanied by a high metabolic demand and elevated requirements for tissue oxygen with eventual increase in oxidative pressure on the antioxidant defence system of the body. Thus, it was based on this premise that some markers of pro-oxidant- antioxidant status of pregnancy compared with non-pregnant state were assessed including, marker of lipid peroxidation (malondialdehyde, MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidise (GPx). A total of 41 apparently healthy female volunteers were used for this study made up of 36 pregnant females at different trimester of pregnancy, categorised into three (3) groups of 12 each per trimester, and whose ages ranged between 19 years and 40 years. Standard biochemical assays were employed in the assessment of these markers. The level of lipid peroxidation (MDA) increased progressively for the pregnant subjects (p<0.05) at the third trimester (18.2mmole/ml) compared to the non-pregnant controls (2.3mmole/ml); an increase in SOD activity was also observed (p<0.05) at the third trimester (8.9U/ml) compared to the control (6.3U/ml) contrary to some other researches; while decrease in CAT (9.2U/ml) and GPx (7.8U/ml) activities at the third trimester compared to the non-pregnant control (p<0.05) (307.5U/ml and 9.4U/ml, respectively) were also observed. There was an observed increase in the body mass index, BMI, from first trimester, 26.4kg/m2 and second trimester, 38.4 kg/m2 to the third trimester, 42.7 kg/m2, compared to the control, 33.7 kg/m2 supporting the claims that pathologic conditions associated with pregnancy become more prominent with increase in BMI. Thus, these biochemical markers of oxidative stress, viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and malondialdehyde (MDA) can serve as markers to assess the stages of pregnancy and also can be used to differentiate pathologic and nonpathologic pregnant conditions.Keywords: Antioxidants; Pregnancy; Pro-oxidants; Trimesters; Free radicals; Body mass inde

Hypocholesterolemic and hypertriglycerolemic effects of chronic cyanide intoxication in rabbits

The effect of chronic cyanide toxicity on liver and serum lipoprotein profiles was investigated in New Zealand White rabbits using a combination of gravimetric and colorimetric procedures. Two groups of three-month-old rabbits (6 per group) were fed either pure growers mash or growers mash containing 400ppm inorganic cyanide for 42 days. Initial and weekly estimation of serum total cholesterol, HDL cholesterol and triacylglycerols were carried out on both groups. Same parameters were estimated in liver on termination of feeding. Results showed that the cyanide treatment led to significant decreases in serum total cholesterol and serum HDL cholesterol while serum triacylglycerols were significantly increased (

Mitigation of cataractogenic potential of cyanide by antioxidant vitamin administration

The effect of antioxidant vitamin (AOV) administration on cyanide-induced ocular damage was investigated in New Zealand White rabbits maintained for 30 days on either pure growers mash or mash + 400ppm cyanide with or without oral AOVs. Cyanide caused significant decreases in superoxide dismutase, catalase and Na+-K+ ATPase; and significant increases in malondialdehyde levels in the lens (p < 0.05). AOVs reversed the elevation in malondialdehyde but had no effect on the enzymes. The results suggest that the damaging effects of oxidative stress imposed by cyanide on the lens can be mitigated by AOVs, probably through enhancement of its antioxidant status rather than directly reversing the inhibition of SOD and catalase. This underscores the need for AOV supplements especially by individuals routinely exposed to habitual, dietary and occupational cyanide

Influence of Annona muricata (soursop) methanolic extracts on antioxidant enzyme and lipid peroxidation status of Wistar rats

Background: In vitro antioxidant assessments on extracts of Annona muricata have revealed the marked antioxidant potentials against deleterious pro-oxidants and most of the beneficial influences of the plant have been identified to be due to its potent annonaceous acetogenins content.Material and Methods: The rats were divided into six groups and administered 100, 200, 400,600, and 800 mg/kg of the fruit, leaf, stem-bark, and root-bark methanolic extracts, i.e.2–6, respectively, whereas group 1 received 2ml of distilled water and served as control. At the end of the administration period of 28days, the rats were sacrificedand blood samples collected for onward biochemical assays using  standard procedures. Plasma antioxidant enzyme activities and lipid peroxidation marker was assessed. Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) were the antioxidant enzymes assayed, while plasma malondialdehyde (MDA) was the lipid peroxidation marker studied.Results: However, the results obtained demonstrated that the various parts of the plant possess potent ability to boost plasma antioxidant enzyme defense and ameliorate lipid peroxidation as the antioxidant activities were elevated markedly across the groups compared to group 1.Conclusion: The leaf and stem-bark were the most potent in boosting the antioxidants (SOD, CAT and GPX) compared to the fruit and root-bark methanolic extracts of Annona muricata.Key words: Annona muricata; lipid peroxidation; Superoxide dismutase; Catalase;Glutathione peroxidase