Anti-apoptotic effects of silk fibroin hydrolysate in RIN5F cell on high glucose condition

Hyperglycemia-induced pancreatic β-cell apoptosis causes serious health complications in diabetic patients. Recently, studies demonstrated that silk and silk-related materials have anti-diabetic effects. We previously reported that silk fibroin hydrolysate (SFH) has anti-diabetic effects through increased pancreatic β-cell mass in type 2 diabetic animals (C57BL/KsJdb/db). However, it is not known whether SFH has anti-apoptotic effects in hyperglycemic conditions. The present study investigates the anti-apoptotic effects of SFH on high glucoseinduced apoptosis using RIN5F cells, a rat pancreatic β-cell line. Hyperglycemic conditions decreased RIN5F cell viability in a concentration-dependent manner. High glucose treatment of 33 mM or higher caused a significant decrease in RIN5F cell viability. However, addition of SFH significantly recovered cell viability in the presence of high glucose. Flow cytometry analysis showed that high glucose treatment significantly increased early stage apoptosis in RIN5F cells. This was inhibited by SFH treatment, which significantly decreased not only early stage apoptosis but also decreased the production of nitrite. Additionally, SFH protected RIN5F cells from oxidative stress-induced apoptosis. These results suggest that SFH has anti-apoptotic effects by protecting pancreatic β-cell from high glucose and/or oxidative stress. Our results support in vivo anti-diabetic effects of SFH and validation of the traditional use of silkworm and silkworm materials in the treatment of diabetes. © 2015 Korean Society for Integrative Biology1111sciescopuskc

Rapid communication Monoclonal antibodies reactive with chicken interleukin-17

Abstract Chicken interleukin-17 (chIL-17) gene was previously characterized through cloning from a chicken intestinal expressed sequence tag (EST) cDNA library. To further investigate the biological properties of chIL-17, six monoclonal antibodies (mAbs) against a bacterially expressed chIL-17 recombinant protein were produced and their binding specificities characterized. Antibodies which were initially selected on the basis of their specific binding reactivity with recombinant chIL-17 in ELISA were further characterized by Western blot analysis. Monoclonal antibodies specific for chIL-17 identified 20 and 21 kDa protein bands in the culture supernatant and cell lysate of CU205 cells. These mAbs also recognized specific bands for chIL-17 in the cell lysate from conconavalin A (Con A)-activated, but not from normal splenic lymphocytes. Furthermore, these mAbs detected a 16 kDa protein in the lysate of CU205 cells treated with tunicamycin and stained an intracellular protein in CU205 cells in flow cytometric analysis. Together, these results indicate that these new mAbs are specific for chIL-17 and will be a useful tool for structural and immunological studies of IL-17 in poultry.