Studies of anti-inflammatory effects of Rooibos tea in rats.

BACKGROUND: Rooibos tea is known to be caffeine free with abundant flavonoids. Aspalathin and nothofagin, the main flavonoids contained in Rooibos tea, have stronger anti-oxidative activity than other flavonoids. As oxidative stress can induce inflammation, the anti-inflammatory effects of Rooibos tea were investigated using a rat colitis model. METHODS: Seven-week-old Wister rats were divided into two groups: one group given Rooibos tea, and one given water. After four weeks of breeding, serum superoxide dismutase (SOD) levels were determined using the Electron Spin Resonance analysis. Urine 8-hydroxy-2'-deoxyguanosine (8-OHdG) concentrations were also determined as reflections of DNA damage using enzyme-linked immunosorbent assay. Furthermore, rats were administrated dextran sodium sulfate (DSS), which is known to induce colitis in rodents, with or without Rooibos tea to evaluate its anti-inflammatory activity. Clinical symptoms, hemoglobin, serum iron and SOD levels were compared between the groups. RESULTS: There were no significant differences in bodyweight gain or laboratory data between the groups. The serum SOD levels were significantly increased, and urine 8-hydroxy-2'-deoxyguanosine levels were significantly decreased in the Rooibos group compared with the controls (P < 0.05 in each). After DSS administration, the serum SOD levels were significantly higher in the Rooibos group compared to the controls (P < 0.05). As a result, a decreased hemoglobin level, observed in the control group, was prevented in the Rooibos group after the DSS challenge. CONCLUSION: Rooibos tea may prevent DNA damage and inflammation by its anti-oxidative activity in vivo. As Rooibos tea is free from caffeine, routine intake may be safe and useful in reducing oxidative stress in children.

Immunological investigation of the hepatic tissue from infants with biliary atresia.

PURPOSE: Matrix metalloproteinases (MMPs) and their endogenous tissue inhibitors [tissue inhibitors of metalloproteinases (TIMPs)] have been implicated in tissue injury and remodeling in many organs. The objective of this study was to evaluate the expression of MMP-3 and -9, and TIMP-1, -2, and -3 and their relationship to liver fibrosis in infants with biliary atresia. METHODS: The expression of MMP-3 and-9 and TIMP-1, -2 and -3 was investigated in liver tissue samples of nine patients with biliary atresia. In addition, the expression of CCR-4 and CCR-5 was analyzed to investigate the activation of Th1 and Th2 cells. The mRNA levels were measured by semiquantitative reverse transcriptase polymerase chain reaction. RESULTS: The expression of MMP-3 was higher than that of MMP-9 in all samples (P < 0.01). The expression of TIMP-1 was higher than that of TIMP-2 and -3 in all samples (P < 0.01). The expression of CCR-5 was higher than that of CCR-4 (P < 0.05), which implied higher activation of Th1 cells relative to Th2 cells. CONCLUSION: Our findings suggest that MMP-3, possibly induced by Th1 cytokines, and its balance with TIMP-1, may be one of the factors involved in the pathogenesis of biliary atresia.

Preliminary phytochemical screening and antimicrobial evaluation of three medicinal plants used in Nigeria.

Methanol extract of three Nigerian medicinal plants were screened for antimicrobial activity using modified Kirby-Bauer disc diffusion and agar dilution techniques to determine the diameters of zone of inhibition and minimum inhibitory concentrations (MIC) of the extracts respectively. The extract of each of the plants were tested against five clinical bacterial isolates comprising of two Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) and three Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumonia) organisms. All the extracts exhibited moderate to high level of antimicrobial activities against these microorganisms. Phytochemical screening of powdered plant material revealed the presence of some secondary metabolites such as alkaloids, saponins, tannins, anthraquinones and flavonoids. These Nigerian medicinal plants could be developed into cheap, safe and culturally acceptable standardized herbal products and may serve as a source of new molecules for broad-spectrum antimicrobial agents.