METHODS: Thirty-five male rabbits of New Zealand strain were randomly assigned to seven groups. For 12 weeks, group CH was fed 1% cholesterol diet only; group C1 was fed 1% cholesterol diet and 0.50 ml/kg/day B. angulata WF juice; group C2 was fed 1% cholesterol diet and 1.00 ml/kg/day B. angulata WF juice; group C3 was fed 1% cholesterol diet and 1.50 ml/kg/day B. angulata WF juice; group N was fed standard pellet only; group N1 was fed standard pellet and 0.50 ml/kg/day B. angulata WF juice; and group N2 was fed standard pellet and 1.00 ml/kg/day B. angulata WF juice.
RESULTS: The three doses reduced the formation of MDA and enhanced the expression of endogenous antioxidant enzymes. The highest dose used (1.50 ml/kg/day) was, however, seen as the most potent.
CONCLUSION: Higher doses of B. angulata juice exerted better antioxidant activity.
SUBJECTS: Female Dark Agouti (DA) rats.
METHODS: Three different dosages of (2 mg/kg of body weight, 3 mg/kg of body weight and 4 mg/kg of body weight) collagen and complete Freund's adjuvant suspension were tested. After 45 days, serum C-reactive protein, TNF-α, superoxide dismutase and total glutathione assays were done. Radiographic and histopathological changes in the joints were compared.
RESULTS: All three groups showed signs of arthritic changes, confirmed by histopathological and radiographic changes. Severe arthritic changes were seen in the rats injected with 4 mg/kg of body weight of collagen. There was a significant increase in C-reactive protein, TNF-α, super oxide dismutase and total glutathione levels in the plasma in arthritis rats and the changes were more significant with 4 mg/kg of collagen.
CONCLUSION: These results demonstrated that the optimal dose to inject to experimental animals in order to get server arthritic changes was 4 mg/kg of collagen with complete Freund's adjuvant suspension. Severe arthritis changes induced significant elevation in plasma C-reactive protein and TNF-α levels.
METHODS: Effects of APC on expressions of genes encoding catalase (katA), superoxide dismutases (SODs), including sodA and sodM, and alkyl hydroperoxide reductase (ahpC) in S· aureus were quantitated by RT-qPCR in reference to gyrA and 16S rRNA. Corresponding activities of the enzymes were also investigated. The Livak analysis was performed for verification of gene-fold expression data. Effects of APC on intracellular and extracellular reactive oxygen species (ROS) levels were determined using the nitroblue tetrazolium (NBT) reduction assay.
RESULTS: APC-treated S· aureus cells had higher sodA and sodM transcripts at 1.5-fold and 0.7-fold expressions respectively with corresponding increase in total SOD activity of 12.24 U/mL compared to untreated cells, 10.85 U/mL (P<0.05). Expression of ahpC was highest in APC-treated cells with 5.5-fold increased expression compared to untreated cells (P<0.05). Correspondingly, ahpC activity was higher in APC-treated cells at 0.672 (A310nm) compared to untreated cells which was 0.394 (A310nm). In contrast, katA expression was 1.48-fold and 0.33-fold lower respectively relative to gyrA and 16S rRNA. Further, APC-treated cells showed decreased catalase activity of 1.8 ×10-4 (U/L or μmol/(min·L)) compared to untreated cells, which was 4.8 ×10-4 U/L (P<0.05). Absorbance readings (A575nm) for the NBT reduction assay were 0.709 and 0.695 respectively for untreated and treated cells, which indicated the presence of ROS. APC-treated S· aureus cells had lower ROS levels both extracellularly and intracellularly, but larger amounts remained intracellularly compared to extracellular levels with absorbances of 0.457 and 0.137 respectively (P<0.05).
CONCLUSION: APC induced expressions of both sodA and sodM, resulting in increased total SOD activity in S· aureus. Higher sodA expression indicated stress induced intracellularly involving O2- , presumably leading to higher intracellular pools of H2O2. A concommittant decrease in katA expression and catalase activity possibly induced ahpC expression, which was increased the highest in APC-treated cells. Our findings suggest that in the absence of catalase, cells are propelled to seek an alternate pathway involving ahpC to reduce stress invoked by O2- and H2O2. Although APC reduced levels of ROS, significant amounts eluded its antioxidative action and remained intracellularly, which adds to oxidative stress in treated cells.