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Chronic ER stress is emerging as a trigger that imbalances a number of systemic and arterial-wall factors and promote atherosclerosis. Macrophage apoptosis within advanced atherosclerotic lesions is also known to increase the risk of atherothrombotic disease. We hypothesize that glucolipotoxicity might mediate monocyte activation and apoptosis through ER stress. Therefore, the aims of this study are (a) to investigate whether glucolipotoxicity could impose ER stress and apoptosis in THP-1 human monocytes and (b) to investigate whether 4-Phenyl butyric acid (PBA), a chemical chaperone could resist the glucolipotoxicity-induced ER stress and apoptosis. Cells subjected to either glucolipotoxicity or tunicamycin exhibited increased ROS generation, gene and protein (PERK, GRP-78, IRE1α, and CHOP) expression of ER stress markers. In addition, these cells showed increased TRPC-6 channel expression and apoptosis as revealed by DNA damage and increased caspase-3 activity. While glucolipotoxicity/tunicamycin increased oxidative stress, ER stress, mRNA expression of TRPC-6, and programmed the THP-1 monocytes towards apoptosis, all these molecular perturbations were resisted by PBA. Since ER stress is one of the underlying causes of monocyte dysfunction in diabetes and atherosclerosis, our study emphasize that chemical chaperones such as PBA could alleviate ER stress and have potential to become novel therapeutics.

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BackgroundFunctionalized gold nanoparticles are emerging as a promising nanocarrier for target specific delivery of the therapeutic molecules in a cancer cell, as a result it targeted selectively to the cancer cell and minimized the off-target effect. The functionalized nanomaterial (bio conjugate) brings novel functional properties, for example, the high payload of anticancer, antioxidant molecules and selective targeting of the cancer molecular markers. The current study reported the synthesis of multifunctional bioconjugate (GNPs-Pep-A) to target the cancer cell.MethodsThe GNPs-Pep-A conjugate was prepared by functionalization of GNPs with peptide-A (Pro-His-Cys-Lys-Arg-Met; Pep-A) using thioctic acid as a linker molecule. The GNPs-Pep-A was characterized and functional efficacy was tested using Retinoblastoma (RB) cancer model in vitro.ResultsThe GNPs-Pep-A target the reactive oxygen species (ROS) in RB, Y79, cancer cell more effectively, and bring down the ROS up to 70 % relative to control (untreated cells) in vitro. On the other hand, Pep-A and GNPs showed 40 and 9 % reductions in ROS, respectively, compared to control. The effectiveness of bioconjugate indicates the synergistic effect, due to the coexistence of both organic (Pep-A) and inorganic phase (GNPs) in novel GNPs-Pep-A functional material. In addition to this, it modulates the mRNA expression of antioxidant genes glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT) by two–threefolds as observed.ConclusionsThe effects of GNPs-Pep-A on ROS reduction and regulation of antioxidant genes confirmed that Vitis vinifera L. polyphenol-coated GNPs synergistically improve the radical scavenging properties and enhanced the apoptosis of cancer cell.

The importance of the polo-like kinase 1 (PLK1) gene is increasing substantially both as a biomarker and as a target for highly specific cancer therapy. This is due to its involvement in multiple points of cell progression and carcinogenesis. PLK1 inhibitors' efficacy in treating human cancers has been limited due to the lack of a specific targeting strategy. Here, we describe a method of targeted downregulation of PLK1 in cancer cells and the concomitant rapid detection of surface lipidomic perturbations using desorption electrospray ionization mass spectrometry (DESI MS). The efficient delivery of siRNA targeting PLK1 gene selectively to the cancer cells is achieved by targeting overexpressed cell surface epithelial cell adhesion molecule (EpCAM) by the EpDT3 aptamer. The chimeric aptamer (EpDT3-siPLK1) showed the knockdown of PLK1 gene expression and PLK1 protein levels by quantitative PCR and western blotting, respectively. The abundant surface lipids, phosphatidylcholines (PCs), such as PC(32:1) (m/z 754.6), PC(34:1) (m/z 782.6), and PC(36:2) (m/z 808.6), were highly expressed in MCF-7 and WERI-RB1 cancer cells compared to normal MIO-M1 cells and they were observed using DESI MS. These overexpressed cell surface lipids in the cancer cells were downregulated upon the treatment of EpDT3-siPLK1 chimera indicating a novel role of PLK1 to regulate surface lipid expression in addition to the efficient selective cancer targeting ability. Our results indicate that DESI MS has a potential ability to rapidly monitor aptamer-mediated cancer therapy and accelerate the drug discovery process. Graphical abstract Binding of aptamer chimera to the cells and changes in lipid profile.

We demonstrate the use of a simple substrate for reliable DESI-MS analysis of cultured cells. This method has the potential to understand various interactions of cells with other external agents. The current method would help in the application of DESI-MS for biology in general and medical sciences in particular.

Well-known purification technologies built for arsenic (As) removal from drinking water are not sustainable, either being unaffordable or inefficient in the elimination of traces of As. In our experiments, we observed that carbonate ion can counteract the effects of As exposure as it efficiently prevented Asinduced cytotoxicity on epithelial cell lines of the small intestine (IEC-6). The cotreatment of IEC-6 cells with 40 ppm of carbonates and As (≥3 ppm) showed substantial remissions in the As-induced cytotoxicity and increased the viability from 50% to 75%. The production of intracellular reactive oxygen species (ROS) and cellular acidification were also reduced in this process (pH increase from 5 to 6.5). Thus, the present study suggests that the cytoprotective effect of carbonate can involve multiple pathways, such as reduction of extracellular/intracellular acidosis, H 2 O 2 decomposition, balancing mitochondrial potential, and immobilization of As. We show that As-contaminated drinking water enriched with carbonates up to 40 ppm has a reduced toxic effect on cells in comparison to that of an As-alone sample. Therefore, carbonates can act as an adjunct in addition to the prevailing approaches to tackle mass poisoning by As. We believe that this study is initial evidence for developing an alternative method to tackle the prevailing mass environmental poisoning by As, using locally available, affordable, safe, and sustainable solutions.

Inactivation of RB is one of the hallmarks of cancer, however gaps remain in our understanding of how RB-loss changes human cells. Here we show that pRB-depletion results in cellular reprogramming, we quantitatively measured how RB-depletion altered the transcriptional, proteomic and metabolic output of non-tumorigenic RPE1 human cells. These profiles identified widespread changes in metabolic and cell stress response factors previously linked to E2F function. In addition, we find a number of additional pathways that are sensitive to RB-depletion that are not E2F-regulated that may represent compensatory mechanisms to support the growth of RB-depleted cells. To determine whether these molecular changes are also present in RB1−/− tumors, we compared these results to Retinoblastoma and Small Cell Lung Cancer data, and identified widespread conservation of alterations found in RPE1 cells. To define which of these changes contribute to the growth of cells with de-regulated E2F activity, we assayed how inhibiting or depleting these proteins affected the growth of RB1−/− cells and of Drosophila E2f1-RNAi models in vivo. From this analysis, we identify key metabolic pathways that are essential for the growth of pRB-deleted human cells.