The defense system against reactive oxygen species is believed to be crucial for the survival of insulin-producing cells after various injuries. The aim of our study was to select a subpopulation of insulin-producing RINm cells with higher resistance to oxidative stress. The cells resistant to hydrogen peroxide (RINmHP) were obtained by repeated exposure of parental RINm cells to 100 and 200 microM hydrogen peroxide (HP). The increased resistance of RINmHP cells to HP was confirmed by three different cytotoxicity assays. In addition, the selected cells also were resistant to the cytotoxic effect of activated rat splenocytes compared to parental cells. The half-life of HP in the RINmHP cell culture medium was about 2.5 times lower than that of the parental cells, corresponding to the increased level of catalase expression and activity in selected cells. The increased defense property of the selected cells was not associated with any significant changes in insulin content and insulin response to a mixture of glucose with isobutyl methyl xanthine or potassium chloride. In conclusion, repeated exposure to HP induces selection of RINm cells with improved resistance to oxidative stress. This improved defense characteristic probably is due to an increased level of catalase expression and activity in the selected cells.
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http://dx.doi.org/10.1016/s0006-2952(03)00198-9 | DOI Listing |
Food Funct
December 2024
School of Nutrition Sciences, Faculty of Health Sciences, University of Ottawa, Ottawa, K1H 8M5, Canada.
Islet amyloid polypeptide (IAPP) fibrillation induces β-cell dysfunction and toxicity in patients with type 2 diabetes. Cytotoxicity is caused by the ability of IAPP fibrils and fibrillar intermediates to permeate the cellular membrane of pancreatic β-cells, trigger endoplasmic reticular stress, induce reactive oxygen species production, and upregulate apoptosis-related genes. Thus, inhibition of IAPP fibrillation is of great interest for preventing associated cytotoxicity.
View Article and Find Full Text PDFBiochem Biophys Res Commun
December 2024
School of Nutrition Sciences, Health Sciences, University of Ottawa, Ottawa, K1H 8M5, Canada; Department of Chemistry and Biomolecular Sciences, Science, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada; University Food Properties and Nutrient Bioavailability, University of Ottawa, Ottawa, Ontario, K1H 8M5, Canada. Electronic address:
Data Brief
December 2024
Friedman Diabetes Institute, Lenox Hill Hospital, Northwell Health, New York, NY, USA.
This paper presents a dataset obtained from an RT-qPCR array analysis of rat pancreatic RIN-m cells treated with two monocarbonyl analogs of curcumin (MACs), C66 and B2BrBC in the presence or absence of streptozotocin (STZ). The array quantified the expression of 84 genes associated with the onset, development, and progression of diabetes. This dataset provides information on the gene expression profiles of pancreatic cells modulated by two specific MACs in a diabetic context.
View Article and Find Full Text PDFBiochem Pharmacol
November 2024
Friedman Diabetes Institute, Lenox Hill Hospital, Northwell Health, New York, NY, USA; Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA; Feinstein Institutes for Medical Research, Manhasset, NY, USA. Electronic address:
The pathogenesis of type 1 diabetes mellitus (T1DM) involves oxidative stress and inflammation. Curcumin, a natural polyphenolic compound found in turmeric, known to exhibit antioxidative and anti-inflammatory properties, is characterized by poor chemical stability, low bioavailability, and rapid metabolism. Monocarbonyl analogs of curcumin (MACs) with a structural absence of β-diketone and enhanced stability and bioavailability present a potential solution to the challenges associated with the use of curcumin.
View Article and Find Full Text PDFChemistry
July 2022
Department of Chemistry, New York University, New York, NY 10003, USA.
Two "hot segments" within an islet amyloid polypeptide are responsible for its self-assembly, which in turn is linked to the decline of β-cells in type 2 diabetes (T2D). A readily available water-soluble, macrocyclic host, cucurbit[7]uril (CB[7]), effectively inhibits islet amyloid polypeptide (IAPP) aggregation through ion-dipole and hydrophobic interactions with different residues of the monomeric peptide in its random-coil conformation. A HSQC NMR study shows that CB[7] likely modulates IAPP self-assembly by interacting with and masking major residues present in the "hot segments" at the N terminus.
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