Previously, we reported that oral feeding of 1% green tea polyphenols (GTPs) aggravated the dextran sulfate sodium (DSS)-induced colitis in mice. In the present study, we assessed the toxicity of 1% GTPs in several organs from normal and DSS-exposed mice. Sixty-two male ICR mice were initially divided into four groups. Nontreated group (group 1, n=15) was given standard diet and water, GTPs (group 2, n=15) received 1% GTPs in diet and water, DSS (group 3, n=15) received diet and 5% DSS in water, and GTPs + DSS group (group 4, n=17) received 1% GTPs in diet and 5% DSS in water. We found that group 4 significantly increased (P<0.05) kidney weight, the levels of serum creatinine and thiobarbituric acid-reactive substances in both kidney and liver, as compared with those in group 3. The mRNA expression levels of antioxidant enzymes and heat-shock proteins (HSPs) in group 4 were lower than those of group 3. For instance, heme oxygenase-1 (HO-1), HSP27, and 90 mRNA in the kidney of group 4 were dramatically down-regulated as compared with those of group 3. Furthermore, 1% GTPs diet decreased the expression of HO-1, NAD(P)H:quinone oxidoreductase 1 (NQO1) and HSP90 in kidney and liver of non-treated mice. Taken together, our results indicate that high-dose GTPs diet disrupts kidney functions through the reduction of antioxidant enzymes and heat-shock protein expressions in not only colitis but also non-treated ICR mice.

Our previous study indicated that a diet containing a high dose (1%) of green tea polyphenols (GTPs) disrupted liver and kidney function via a reduction in antioxidant enzyme and heat shock protein (HSP) levels in both colitis and non-treated ICR mice. In the present study, we assessed the effects of 0.01%, 0.1%, and 1% dietary GTPs on liver and kidney physiological functioning in dextran sulfate sodium (DSS)-exposed and normal mice. GTPs at 0.01% and 0.1% significantly suppressed DSS-increased serum aspartate 2-oxoglutarate aminotransferase (AST) and alanine aminotransferase (ALT) levels. In contrast, GTPs at 1% increased kidney weight, serum creatinine levels, and thiobarbituric acid-reactive substances (TBARs) in both the kidney and the liver in normal mice, as compared with DSS-exposed mice. GTPs at 0.01% and 0.1% remarkably upregulated the expression of heme oxygenase-1 (HO-1) and heat shock protein 70 (HSP70) mRNA in the liver and kidney of mice exposed to DSS, whereas GTPs at 1% abolished it. Our results indicate that low and medium doses of GTPs have beneficial effects on DSS-induced hepatotoxicity and nephrotoxicity via upregulation of self-protective enzymes, while these effects disappeared at a high dose.

In order to obtain the polarization dependence of optical transitions in GaAs/AlGaAs quantum dot structures, a three-dimensional SchrSdinger equation describing the heavy hole-light hole mixing via a k * p formalism is solved. The polarization dependence is investigated as a function of the symmetry of the quantum dot, indicating that the polarization dependence is very sensitive to the symmetry of the confining structure. We also examine how the optical properties of the quantum dot evolve towards those of a quantum wire by allowing one axis of the dot to increase.

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