Posts Tagged ‘J Agric Food Chem’

Anthocyanins induce the activation of phase II enzymes through the antioxidant response element pathway against oxidative stress-induced apoptosis.

Wednesday, January 28th, 2009

http://www.ncbi.nlm.nih.gov/pubmed/17935293?dopt=AbstractPlus

1: J Agric Food Chem. 2007 Nov 14;55(23):9427-35. Epub 2007 Oct 13.

Anthocyanins induce the activation of phase II enzymes through the antioxidant response element pathway against oxidative stress-induced apoptosis.
Shih PH, Yeh CT, Yen GC.

Department of Food Science and Biotechnology, National Chung Hsing University, 250 Kuokuang Road, Taichung 40227, Taiwan.

Reactive oxygen species (ROS)-induced cell damage is inevitable and severe and is involved in numerous diseases, including cancer. Reducing oxidative stress is one of the strategies of chemoprevention. Anthocyanins are naturally occurring flavonoids that show multiple benefits. We first pointed out the effects of anthocyanins in the contributions to activation of phase II antioxidant and detoxifying enzymes, chemopreventive potency, and involved transcriptional regulation. Our results obtained in rat liver Clone 9 cells showed that treatment of anthocyanins leads to positive effects on elevating the antioxidant capacity, including activated expression of glutathione-related enzymes (glutathione reductase, glutathione peroxidase, and glutathione S-transferase) and recruited GSH content. In addition, the activity of NAD(P)H: quinone oxidoreductase (NQO1) was also promoted under the treatment of anthocyanin. This influential functions as the defense system against programmed cell death induced by H2O2. The capacity for induction of luciferase expression by anthocyanins in cells transfected with rat nqo1-promoter constructed plasmid was further investigated; we found that the molecular mechanism is related to the activation of antioxidant response element (ARE) upstream of genes that are involved in antioxidation and detoxification. Our data suggest that natural anthocyanins are recommended as chemopreventive phytochemicals and could stimulate the antioxidant system to resist oxidant-induced injury. And, more important, the promoting effect of anthocyanins on ARE-regulated phase II enzyme expression seems to be a critical point in modulating the defense system against oxidative stress.

PMID: 17935293 [PubMed - indexed for MEDLINE]

Protective Effects of Bilberry (Vaccinium myrtillus L.) Extract on KBrO3-Induced Kidney Damage in Mice.

Monday, January 26th, 2009

J Agric Food Chem. 2008 Jan 23;56(2):420-5. Epub 2007 Dec 20. Links

Protective Effects of Bilberry (Vaccinium myrtillus L.) Extract on KBrO3-Induced Kidney Damage in Mice.

Bao L, Yao XS, Tsi D, Yau CC, Chia CS, Nagai H, Kurihara H.

Hiroshi_Kurihara@163.com, tyaoxs@jnu.edu.cn.

Potassium bromate (KBrO 3) is an oxidizing agent used as a food additive which causes kidney damage as a potent nephrotoxic agent, and the mechanism may be explained by the generation of oxygen free radicals. Our experiments showed that single intraperitoneal administration of 200 mg/kg KBrO 3 could induce serious kidney damage, with an increase in serum blood urea nitrogen (BUN) and creatinine levels. Five-day oral administration of bilberry ( Vaccinium myrtillus L.) extract at 50, 100, and 200 mg/kg resulted in a reversal in serum BUN and creatinine to normal levels and decreased kidney malondialdehyde (MDA), nitric oxide (NO), and xanthine oxidase (XOD) levels. Also, bilberry extract improved oxygen radical absorbance capacity (ORAC) levels in kidney tissue, which showed that bilberry extract reduced the degree of oxidative stress and kidney damage induced by KBrO 3. These findings demonstrate that the protective effect of bilberry extract is attributed to its free radical scavenging activity and lipid peroxidation inhibitory effect.

PMID: 18092757 [PubMed - in process]