Co-enzyme Q10 and acetyl salicylic acid enhance Hsp70 expression in primary chicken myocardial cells to protect the cells during heat stress In the original publication of the article, one of the images was selected by mistake in Fig. 3 (HS + ASA, 5 h). The correct version of Fig. 3 is given in this correction.

G protein-coupled receptor kinase 5 modifies cancer cell resistance to paclitaxel Abstract G protein-coupled receptor kinases (GRKs) phosphorylate the activated forms of G protein-coupled receptors (GPCRs), leading to receptor desensitization and internalization. In addition, GRKs can modify the activity of many non-GPCR-signaling pathways as well, controlling other cellular functions beyond that directly associated with a GPCR. In this report, we show that cervical cancer HeLa cells and breast cancer MDA MB 231 cells with reduced GRK5 expression display increased sensitivity to the apoptotic effects of paclitaxel (Taxol). This effect in cancer cells with low GRK5 levels could be because of blunted histone deacetylase 6 (HDAC6) activity that leads to an increase in α-tubulin acetylation levels, which augments paclitaxel sensitivity. We demonstrate that GRK5 and HDAC6 form a signaling complex in cells and in vitro. GRK5 phosphorylates HDAC6 at Ser-21 to promote its deacetylase activity. Therefore, the GRK5–HDAC6 interaction may contribute to paclitaxel resistance in cancer cells.

miR-940 regulates the inflammatory response of chondrocytes by targeting MyD88 in osteoarthritis Abstract Osteoarthritis (OA) has been identified to be one of the most prevalent forms of joint disorders, marked with inflammatory immune response that may give rise to several complications including disability. Numbers of investigations have proven that microRNA play a key role in chondrogenesis regulation. Accordingly, the current study was intended to explore more about the potential role of miR-940 in the regulation of immune response, pertaining to osteoarthritis. Our findings indicated miR-940 associated down-regulation in both, the tissue as well as at cellular levels, i.e. chondrocytes that are being induced with IL-1β. However, the expression of MyD88 was found to be opposite. Moreover, our findings indicated that miR-940 targets MyD88 to regulate its expression. The study was based on the proposition that normal human chondrocytes when induced with IL-1β significantly enhanced the level of inflammation along with simultaneous stimulation of NF-κB signaling mechanism. Alternatively, siRNA against MyD88, miR-940 mimic or the NF-κB inhibitor, reversed the effect of IL-1β. The chondrocytes that were transfected with miR-940 inhibitor increased the secretion of inflammatory cytokines and activated NF-κB. Furthermore, the expression of miR-490 was reduced in vivo, which was increased through an injection of lentivirus, to foster the production of necessary cytokines and NF-κB and the down-regulation of MyD88. In conclusion, the pathogenesis of OA can be regulated by miR-940/MyD88 axis, which can be achieved through the combined signaling mechanism of MyD88/NF-κB signaling, induced with the help of IL-1β.

Enforced lysosomal biogenesis rescues erythromycin- and clindamycin-induced mitochondria-mediated cell death in human cells Abstract Antibiotics are the front-line treatment against many bacterial infectious diseases in human. The excessive and long-term use of antibiotics in human cause several side effects. It is important to understand the underlying molecular mechanisms of action of antibiotics in the host cell to avoid the side effects due to the prevalent uses. In the current study, we investigated the crosstalk between mitochondria and lysosomes in the presence of widely used antibiotics: erythromycin (ERM) and clindamycin (CLDM), which target the 50S subunit of bacterial ribosomes. We report here that both ERM and CLDM induced caspase activation and cell death in several different human cell lines. The activity of the mitochondrial respiratory chain was compromised in the presence of ERM and CLDM leading to bioenergetic crisis and generation of reactive oxygen species. Antibiotics treatment impaired autophagy flux and lysosome numbers, resulting in decreased removal of damaged mitochondria through mitophagy, hence accumulation of defective mitochondria. We further show that over-expression of transcription factor EB (TFEB) increased the lysosome number, restored mitochondrial function and rescued ERM- and CLDM-induced cell death. These studies indicate that antibiotics alter mitochondria and lysosome interactions leading to apoptotsis and may develop a novel approach for targeting inter-organelle crosstalk to limit deleterious antibiotic-induced side effects.

SC79, a novel Akt activator, protects dopaminergic neuronal cells from MPP + and rotenone Abstract In pathogenesis of Parkinson’s disease (PD), mitochondrial dysfunction causes substantial reactive oxygen species (ROS) production and oxidative stress, leading to dopaminergic (DA) neuronal cell death. Mitochondrial toxins, including MPP+ (1-methyl-4-phenylpyridinium ion) and rotenone, induce oxidative injury in cultured DA neuronal cells. The current study tested the potential effect of SC79, a first-in-class small-molecule Akt activator, against the process. In SH-SY5Y cells and primary murine DA neurons, SC79 significantly attenuated MPP+- and rotenone-induced viability reduction, cell death, and apoptosis. SC79 activated Akt signaling in DA neuronal cells. Akt inhibition (by LY294002 and MK-2206) or CRISPR-Cas9-mediated Akt1 knockout completely abolished SC79-induced DA neuroprotection against MPP+. Further studies demonstrated that SC79 attenuated MPP+- and rotenone-induced ROS production, mitochondrial depolarization, and lipid peroxidation in SH-SY5Y cells and primary DA neurons. Moreover, upregulation of Nrf2-dependent genes (HO1 and NQO1) and Nrf2 protein stabilization were detected in SC79-treated SH-SY5Y cells and primary DA neurons. Together we show that SC79 protects DA neuronal cells from mitochondrial toxins possibly via activation of Akt-Nrf2 signaling.

Effects of different dietary regimes alone or in combination with standardized Aronia melanocarpa extract supplementation on lipid and fatty acids profiles in rats Abstract This study investigated different dietary strategies, high-fat (HFd), or standard diet (Sd) alone or in combination with standardized Aronia melanocarpa extract (SAE), as a polyphenol-rich diet, and their effects on lipids and fatty acids (FA) in rats with metabolic syndrome (MetS). Wistar albino rats were randomly divided into two groups: healthy and rats with MetS, and then depending on dietary patterns on six groups: healthy rats fed with Sd, healthy rats fed with Sd and SAE, rats with MetS fed with HFd, rats with MetS fed with HFd and SAE, rats with MetS fed with Sd, and rats with MetS fed with Sd and SAE. 4 weeks later, after an overnight fast (12–14 h), blood for determination of total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), index of lipid peroxidation (measured as TBARS), and FA was collected. Increased FA and lipid concentration found in MetS rats were reduced when changing dietary habits from HFd to Sd with or without SAE consumption. Consumption of SAE slightly affects the FA profiles, mostly palmitoleic acid in healthy rats and PUFA in MetS + HFd rats. Nevertheless, in a high-fat diet, SAE supplementation significantly decreases n-6/n-3 ratio, thereby decreasing systemic inflammation. Further researches are warranted to confirm these effects in humans.

Proteomic analysis of peripheral blood polymorphonuclear cells (PBMCs) reveals alteration of neutrophil extracellular trap (NET) components in uncontrolled diabetes Abstract Neutrophils have been thought to play a major role in inflammation and diabetic complications especially in poor glycemic control patients as demonstrated by their aberrant inflammatory markers. The aim of the present study was to compare neutrophil proteome profiles between diabetic patients with good glycemic control and those with poor glycemic control to see whether there might be any differences that could be related to the cause of complications which are found more commonly in the latter. Using 2-dimensional gel electrophoresis (2-DE) followed by quadrupole time of flight mass spectrometry (Q-TOF MS) and/or tandem mass spectrometry (MS/MS), we identified 35 differentially expressed proteins, some of which were protein components of neutrophil extracellular traps (NETs), in the poor glycemic control group compared to the good glycemic control group. The observed alterations of protein components of NETs included downregulation of myeloperoxidase, azurocidin (CAP37), and S100A9; and upregulation of the glycolytic enzymes transketolase and alpha-enolase. Manganese superoxide dismutase (MnSOD), functioning in cellular response and defense, was also found downregulated in the poor control group. Most of the glycolysis-related proteins were downregulated in the good control group but upregulated in the poor control group, including phosphoglycerate kinase 1 (PGK1) and L-lactate dehydrogenase B chain (LDHB). The findings of this study demonstrate the dysregulation of protein components of NETs in neutrophils in patients with poorly controlled diabetes. More specifically, these findings suggest association between NETs and inflammation in diabetes and provide further insights into the role of neutrophils in the complications of poorly controlled diabetes.

Downregulation of long non-coding RNA TUG1 suppresses tumor growth by promoting ubiquitination of MET in diffuse large B-cell lymphoma Abstract Long non-coding RNAs (lncRNAs) can modulate gene expression through different mechanisms, but the fundamental molecular mechanism between lncRNAs and MET protein in diffuse large B-cell lymphoma (DLBCL) was poorly understood. The expression of lncRNA TUG1 and MET in DLBCL tissues and cell lines was determined by quantitative real-time PCR and western blotting. Cell proliferation, invasion and apoptosis were determined by cell counting kit-8 assay, transwell assay and flow cytometer. The animal xenograft model was established by the injection of DLBCL cells carrying si-TUG1. The expression of TUG1 and MET was upregulated in DLBCL tissues and cells. We demonstrated that MET was altered in the TUG1 knockdown DLBCL cells, and confirmed the interaction between TUG1 and MET by RNA pull-down and RNA immunoprecipitation. Furthermore, knockdown of TUG1 reduced MET protein level by promoting ubiquitination, and suppressed tumor growth in vitro and in vivo. Our findings demonstrated that TUG1 exerted its oncogenic function in DLBCL by inhibiting the ubiquitination and the subsequent degradation of MET. Knockdown of TUG1 through MET downregulation suppressed DLBCL cell proliferation and tumor growth.

Azoramide improves mitochondrial dysfunction in palmitate-induced insulin resistant H9c2 cells Abstract Azoramide is identified as a new compound with the dual properties for the improvement of ER-folding capacity in various cells as well as for the treatment of T2DM. Although the effect of azoramide in glucose-homeostasis in mammalians is not known very well, a limited number of experimental studies showed that it could improve the insulin sensitivity in genetically obese mice. Therefore, here, we aimed to investigate the direct effect of azoramide on insulin signaling in insulin-resistant (IR) cardiomyocytes using IR-modelled ventricular cardiomyocytes. This model was established in H9c2 cells using palmitic acid incubation (50-μM for 24-h). The development of IR in cells was verified by monitoring the cellular 2-DG6P uptake assays in these treated cells. The 2-DG6P uptake was 50% less in the IR-cells compared to the control cells, while azoramide treatment (20-μM for 48-h) could prevent fully that decrease. In addition, azoramide treatment markedly preserved the IR-induced less ATP production and high-ROS production in these IR-cells. Furthermore, this treatment prevented the functional changes in mitochondria characterized by depolarized mitochondrial membrane potential and mitochondrial fusion or fusion-related protein levels as well as cellular ATP level. Moreover, this treatment provided marked protection against IR-associated changes in the insulin signaling pathway in cells, including recovery in the phosphorylation of IRS1 and Akt as well as the protein level of GLUT4 and Akt. Our present results, for the first time, demonstrated that azoramide plays an important protective role in IR-cardiomyocytes, at most, protective action on mitochondria. Therefore, one can suggest that azoramide, as a novel regulator, can provide direct cardioprotection in the IR-heart, at most, via affecting mitochondria and can be a good candidate as a new drug for the treatment of IR-associated cardiovascular disorders in mammalians with systemic IR.

TGF-β2 antagonizes IL-6-promoted cell survival Abstract Transforming growth factor beta is a key cytokine involved in the pathogenesis of fibrosis in many organs, whereas interleukin-6 plays an important role in the regulation of inflammation. They are both potent angiogenesis inducers with opposite effects on cell survival and apoptosis. TGF-β2 induces apoptosis; in contrast, IL-6 protects cells from apoptosis. The possible interaction between these two cytokines is indicated in various disease states. In this study, we have assessed the effect of TGF-β2 on IL-6 signaling and found that TGF-β2 could strongly inhibit IL-6-induced STAT3 activation and synergy with IL-6 resulting in enhanced SOCS3 expression. Interestingly, IL-6 also slows down the decay of TGF-β2 mRNA. Consistent with this mechanism, we found that TGF-β2 could antagonize IL-6 effect on cell survival in both γ-irradiation and UV light-induced apoptosis. Taken together, the finding shows that TGF-β2 serves as a negative regulator of IL-6 signaling and antagonizes the anti-apoptosis effect of IL-6.