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Portable and low-cost analytical devices are essential for rapid detection of bioactive substrates in agricultural products. This study presents the first highly integrated microelectrochemical sensor based on pencil graphite for rapid and sensitive detection of hesperidin in Citrus reticulate 'Chachi' peel. The surface morphology and characterization as well as the electrochemical property of pencil graphite was investigated and discussed. A high electrocatalytic efficiency of hesperidin has been found at used pencil graphite-based microelectrodes. Kinetic analysis was carried out to further understand the electrochemical process of hesperidin at a pencil graphite microelectrode. Consequently, a portable and highly-integrated microelectrochemical sensor exhibits a sensitivity of 0.7251 μA cm−2 μM−1 and a detection limit as low as 25 nM (S/N = 3), and high selectivity was fabricated. Proposed microelectrochemical sensors were applied to electrochemically determinate the hesperidin content in the extract of Citrus reticulata "chachi" peel. As a result, the concentration of hesperidin in the actual real sample detected electrochemically with the proposed portable and low-cost microelectrochemical sensors is highly consistent to that obtained with a common chromatographic method, thus indicating the good reliability and that it can be used in practical applications. [ABSTRACT FROM AUTHOR]

Procyanidins can alleviate small-intestine damage induced by acrylamide (ACR). However, little is known about whether procyanidins, after gastrointestinal digestion, can prevent ACR-induced intestinal barrier damage and the possible mechanism. Here, Caco-2 cells were differentiated into an intestinal epithelial cell monolayer membrane, which was stimulated with or without ACR in the presence or absence of procyanidin A 1 (A 1 ) and its digestive products (D-A 1 ). Our findings show that both A 1 and D-A 1 significantly increased the transepithelial electrical resistance (TEER) value; decreased FITC-dextran 4 kDa (FITC-4 kDa) permeability, apoptosis and lactic dehydrogenase (LDH) release; and enhanced the expression of claudin-1, occludin and zonula occludens-1 (ZO-1) in ACR-induced Caco-2 cell monolayer membrane. In addition, A 1 and D-A 1 suppressed ACR-induced phosphorylation of mitogen-activated protein kinase (MAPK). Finally, A 1 and D-A 1 inhibited the myosin light chain kinase (MLCK) signaling pathway, thereby maintaining normal intestinal barrier functions, similar to the MLCK inhibitor in ACR-induced Caco-2 cell monolayer membrane. These findings indicate that A 1 can alleviate ACR-induced intestinal barrier dysfunction via inhibiting the MAPK/MLCK signaling pathway, and it still has excellent inhibitory effects after digestion.

It has been reported that B-type procyanidins can alleviate oxidative damage of prostatic cells, but there has been limited information on the similar role of A-type procyanidins. This study investigated the protective effect of procyanidin A-type dimers from peanut skin against H 2 O 2 -induced oxidative stress damage in prostate cancer DU145 cells. According to the UPLC-Q-TOF-MS/MS analysis and comparison with standards, the fourth fraction of peanut skin procyanidin (PSP-4) was identified as procyanidin A-type dimers, namely, procyanidin A 1 and A 2 . Results revealed that PSP-4 treatment prior H 2 O 2 exposure increased cell activity and attenuated the cell cycle arrest and apoptosis rate. The H 2 O 2 -induced increase in intracellular reactive oxygen species (ROS) was remarkably inhibited by PSP-4. PSP-4 treatment enhanced the activity of catalase (CAT) and total super oxide dismutase (T-SOD) and restored glutathione (GSH) content, compared with the H 2 O 2 treatment. Furthermore, the results indicated that PSP-4 protected DU145 cells by attenuating phosphorylation of the mitogen-activated protein kinases (MAPKs), by increasing the Bcl-2/Bax ratio, and by reducing the activation of caspase-3 and caspase-9 by cascade reactions. This study reveals that procyanidin A-type dimers from peanut skin have the potential function in preventing oxidative stress damage of prostatic cells., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Primary nephrotic syndrome (PNS) is a devastating pediatric disorder. However, its mechanism remains unclear. Previous studies detected B7-1 in podocytes; meanwhile, γδ T cells play pivotal roles in immune diseases. Therefore, this study aimed to assess whether and how γδ T cells impact podocytes via the CD28/B7-1 pathway. WT and TCR δ -/- mice were assessed. LPS was used to induce nephropathy. Total γδ T and CD28 + γδ T cells were quantitated in mouse spleen and kidney samples. B7-1 and phosphor-SRC levels in the kidney were detected as well. In vitro, γδ T cells from the mouse spleen were cocultured with mouse podocytes, and apoptosis rate and phosphor-SRC expression in podocytes were assessed. Compared with control mice, WT mice with LPS nephropathy showed increased amounts of γδ T cells in the kidney. Kidney injury was alleviated in TCR δ -/- mice. Meanwhile, B7-1 and phosphor-SRC levels were increased in the kidney from WT mice with LPS nephropathy. CD28 + γδ T cells were decreased, indicating CD28 may play a role in LPS nephropathy. Immunofluorescence colocalization analysis revealed a tight association of γδ T cells with B7-1 in the kidney. High B7-1 expression was detected in podocytes treated with LPS. Podocytes cocultured with γδ T cells showed higher phosphor-SRC and apoptosis rate than other cell groups. Furthermore, CD28/B7-1 blockage with CTLA4-Ig in vitro relieved podocyte injury. γδ T cells exacerbate podocyte injury via CD28/B7-1 signaling, with downstream involvement of phosphor-SRC. The CD28/B7-1 blocker CTLA4-Ig prevented progressive podocyte injury, providing a potential therapeutic tool for PNS.