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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Anthocyanins, Blotting, Western, Cells, Cultured, Chromatography, High Pressure Liquid, Free Radicals, Glucosides, Glutathione S-Transferase pi, Heme Oxygenase-1, Humans, Hydrogen Peroxide, Oxidative Stress, Pigment Epithelium of Eye, Plant Extracts, RNA, Messenger, Reverse Transcriptase Polymerase Chain Reaction, Signal Transduction, Up-Regulation, Vaccinium myrtillus.
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Do bilberry ( Vaccinium myrtillus ) anthocyanins modulate heme oxygenase-1 and glutathione S-transferase-pi expression in ARPE-19 cells? Context: To determine whether anthocyanin-enriched bilberry extracts modulate pre- or posttranslational levels of oxidative stress defense enzymes heme-oxygenase (HO)-1 and glutathione S-transferase-pi (GST-pi) in cultured human retinal pigment epithelial (RPE) cells. Confluent ARPE-19 cells were preincubated with anthocyanin and nonanthocyanin phenolic fractions of a 25% enriched extract of bilberry (10(-6)-1.0 mg/mL) and, after phenolic removal, cells were oxidatively challenged with H(2)O(2). The concentration of intracellular glutathione was measured by HPLC and free radical production determined by the dichlorofluorescin diacetate assay. HO-1 and GST-pi protein and mRNA levels were determined by Western blot and RT-PCR, respectively. Preincubation with bilberry extract ameliorated the intracellular increase of H(2)O(2)-induced free radicals in RPE, though H(2)O(2) cytotoxicity was not affected. By 4 hours, the extract had upregulated HO-1 and GST-pi protein by 2.8- and 2.5-fold, respectively, and mRNA by 5.5- and 7.1-fold, respectively, in a dose-dependent manner. Anthocyanin and nonanthocyanin phenolic fractions contributed similarly to mRNA upregulation.
assistant
Anthocyanins and other phenolics from bilberry upregulate the oxidative stress defense enzymes HO-1 and GST-pi in RPE, suggesting that they stimulate signal transduction pathways influencing genes controlled by the antioxidant response element. Final Decision: yes