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Caenorhabditis elegans (C. elegans) is a robust model organism in cell biology, physiology, pharmacology, and toxicology. It is widely recognized for its short lifespan (about 30 days), rapid life cycle, and genetic similarities to mammals. Known for their utility in lifespan research, compounds identified in C. elegans studies have shown lifespan-extending effects in higher organisms, making them invaluable for aging research. Recent work has highlighted the importance of food source conditions, specifically whether C. elegans is fed live or dead Escherichia coli (E. coli) OP50, and solvents like dimethyl sulfoxide (DMSO) in evaluating compound efficacy and organismal health. In this study, we employed C. elegans health lifespan auto-monitoring system (C-HAS), an automated imaging technology capable of objectively analyzing lifespan and healthspan by tracking movement patterns in real-time. Our results reveal that C. elegans fed dead bacteria, specifically heat-killed (HK) and freeze-dried (Fd) E. coli , display extended lifespan and healthspan compared to those fed live bacteria, reducing the proportion of short-lived, unhealthy nematodes. Moreover, 0.1 % DMSO treatment, a concentration previously reported as not affecting nematode longevity, notably shortens both lifespan and healthspan in C. elegans under dead bacterial conditions, with similar negative effects observed across different dead bacteria types. These findings highlight the importance of considering bacterial food state and DMSO presence when conducting lifespan and healthspan studies in C. elegans. This work provides foundational insights into how specific experimental conditions impact the health quality of C. elegans , advancing our understanding of environmental influences on organismal aging. [Display omitted] • Dead bacterial feeding conditions extend C. elegans lifespan and healthspan. • 0.1 % DMSO shortened lifespan and healthspan under dead bacterial conditions. • C. elegans healthy aging is influenced by dietary state and solvent, particularly DMSO. [ABSTRACT FROM AUTHOR]

To promote the recovery of cells that undergo intracellular ice formation (IIF), it is imperative that the recrystallization of intracellular ice is minimized. Hepatocytes are more prone to IIF than most mammalian cells, and thus we assessed the ability of novel small molecule carbohydrate-based ice recrystallization inhibitors (IRIs) to permeate and function within hepatocytes. HepG2 monolayers were treated with N-(4-chlorophenyl)- d -gluconamide (IRI 1), N-(2-fluorophenyl)- d -gluconamide (IRI 2), or para-methoxyphenyl-β-D-glycoside (IRI 3) and fluorescent cryomicroscopy was used for real time visualization of intracellular ice recrystallization. Both IRI 2 and IRI 3 reduced rates of intracellular recrystallization, whereas IRI 1 did not. IRI 2 and IRI 3, however, demonstrated a marked reduction in efficiency in the presence of the most frequently used permeating cryoprotectants (CPAs): glycerol, propylene glycol (PG), dimethyl sulfoxide (DMSO), and ethylene glycol (EG). Nevertheless, IRI 3 reduced rates of intracellular recrystallization relative to CPA-only controls in the presence of glycerol, PG, and DMSO. Interestingly, IRI preparation in trehalose, a commonly used non-permeating CPA, did not impact the activity of IRI 3. However, trehalose did increase the activity of IRI 1 while decreasing that of IRI 2. While this study suggests that each of these compounds could prove relevant in hepatocyte cryopreservation protocols where IIF would be prominent, CPA-mediated modulation of intracellular IRI activity is apparent and warrants further investigation. [ABSTRACT FROM AUTHOR]

Nitro-containing compounds such as nitrofuran and nitroimidazole are drugs used for the treatment of infectious diseases. However, many of these nitro-containing drugs are positive in the bacterial reverse mutation assay (Ames test). The recently approved anti-multidrug-resistant tuberculosis (MDR-TB) drug, delamanid (Deltyba™; OPC-67683), a derivative of 4-nitroimidazole, was negative for mutagenicity in the Ames assay. In Salmonella typhimurium , mutagenicity of nitro compounds has been closely associated with the ability of nitroreductase to metabolize (degradation)these compounds. To explore the lack of mutagenicity for delamanid, we examined the initial metabolic rate and mutagenic-specific activity of a series of nitro compounds in S. typhimurium TA100. The order of maximum mutagenic-activity was nitrofuran > 2-nitroimidazole > 5-nitroimidazole ≥ 4-nitroimidazole, which is very similar to the order of initial metabolic rate, i.e., the Pearson's correlation coefficient (r = 0.85) showed a correlation between metabolic rate and mutagenic-activity. No metabolism of delamanid was detected even after 60 h of treatment. In addition, delamanid was not reduced by two human nitroreductases. These facts may explain the absence of genotoxicity of delamanid in both in vitro and in vivo tests. [ABSTRACT FROM AUTHOR]

Highlights: [•] 11-mer peptide Lumbricusin, a defensin like peptide, is isolated from earthworm. [•] We here demonstrated that Lumbricusin has neurotropic and neuroprotective effects. [•] p27 degradation by Lumbricusin mediates effects of Lumbricusin on neuronal cells. [ABSTRACT FROM AUTHOR]

Highlights: [•] A simple and economical method has been developed for the determination of pyrethroid pesticides. [•] The method is based on a DLLME technique after a LLE step. [•] The method was successfully applied in determination of target analytes in vegetable oils. [•] Significant matrix effects were not observed in oil sample analysis. [Copyright &y& Elsevier]

Abstract: The naturally occurring SV23 splice variant of human constitutive androstane receptor (hCAR-SV23) is activated by di-(2-ethylhexyl)phthalate (DEHP), which is detected as a contaminant in fetal bovine serum (FBS). In our initial experiment, we compared the effect of dialyzed FBS, charcoal-stripped, dextran-treated FBS (CS-FBS), and regular FBS on the basal activity and ligand-activation of hCAR-SV23 in a cell-based reporter gene assay. In transfected HepG2 cells cultured in medium supplemented with 10% FBS, basal hCAR-SV23 activity varied with the type of FBS (regular>dialyzed>CS). DEHP increased hCAR-SV23 activity when 10% CS-FBS, but not regular FBS or dialyzed FBS, was used. With increasing concentrations (1–10%) of regular FBS or CS-FBS, hCAR-SV23 basal activity increased, whereas in DEHP-treated cells, hCAR-SV23 activity remained similar (regular FBS) or slightly increased (CS-FBS). Subsequent experiments identified a serum-free culture condition to detect DEHP activation of hCAR-SV23. Under this condition, artemisinin, artemether, and arteether increased hCAR-SV23 activity, whereas they decreased it in cells cultured in medium supplemented with 10% regular FBS. By comparison, FBS increased the basal activity of the wild-type isoform of hCAR (hCAR-WT), whereas it did not affect the basal activity of the SV24 splice variant (hCAR-SV24) or ligand activation of hCAR-SV24 and hCAR-WT by 6-(4-chlorophenyl)imidazo[2,1-b][1,3]thiazole-5-carbaldehyde O-(3,4-dichlorobenzyl)oxime (CITCO). The use of serum-free culture condition was suitable for detecting CITCO activation of hCAR-WT and hCAR-SV24. In conclusion, FBS leads to erroneous classification of pharmacological ligands of hCAR-SV23 in cell-based assays, but investigations on functional ligands of hCAR isoforms can be conducted in serum-free culture condition. [Copyright &y& Elsevier]

Abstract: The Ebola virus (EBOV) genome only encodes a single viral polypeptide with enzymatic activity, the viral large (L) RNA-dependent RNA polymerase protein. However, currently, there is limited information about the L protein, which has hampered the development of antivirals. Therefore, antifiloviral therapeutic efforts must include additional targets such as protein–protein interfaces. Viral protein 35 (VP35) is multifunctional and plays important roles in viral pathogenesis, including viral mRNA synthesis and replication of the negative-sense RNA viral genome. Previous studies revealed that mutation of key basic residues within the VP35 interferon inhibitory domain (IID) results in significant EBOV attenuation, both in vitro and in vivo. In the current study, we use an experimental pipeline that includes structure-based in silico screening and biochemical and structural characterization, along with medicinal chemistry, to identify and characterize small molecules that target a binding pocket within VP35. NMR mapping experiments and high-resolution x-ray crystal structures show that select small molecules bind to a region of VP35 IID that is important for replication complex formation through interactions with the viral nucleoprotein (NP). We also tested select compounds for their ability to inhibit VP35 IID–NP interactions in vitro as well as VP35 function in a minigenome assay and EBOV replication. These results confirm the ability of compounds identified in this study to inhibit VP35–NP interactions in vitro and to impair viral replication in cell-based assays. These studies provide an initial framework to guide development of antifiloviral compounds against filoviral VP35 proteins. [Copyright &y& Elsevier]

Abstract: 2-Aminoethoxydiphenyl borate (2-APB) is used as a pharmacological tool because it antagonizes inositol 1,4,5-trisphosphate receptors and store-operated Ca2+ (SOC) channels, and activates some TRP channels. Recently, we reported that 2-APB enhanced the increase in cytotoxic [Ca2+]i, resulting in cell death under external acidic conditions in rat pheochromocytoma cell line PC12. However, the molecular mechanism and functional role of the 2-APB-induced Ca2+ influx in PC12 have not been clarified. In this study, to identify the possible target for the action of 2-APB we examined the pharmacological and molecular properties of [Ca2+]i and secretory responses to 2-APB under extracellular low pH conditions. 2-APB dose-dependently induced a [Ca2+]i increase and dopamine release, which were greatly enhanced by the external acidification (pH 6.5). [Ca2+]i and secretory responses to 2-APB at pH 6.5 were inhibited by the removal of extracellular Ca2+ and SOC channel blockers such as SK&F96365, La3+ and Gd3+. PC12 expressed all SOC channel molecules, Orai 1, Orai 2 and Orai 3. When we used an siRNA system, downregulation of Orai 3, but not Orai 1 and Orai 2, attenuated both [Ca2+]i and secretory responses to 2-APB. These results suggest that 2-APB evokes external acid-dependent increases of [Ca2+]i and dopamine release in PC12 through the activation of Orai 3. The present results indicate that 2-APB may be a useful pharmacological tool for Orai channel-related signaling. [Copyright &y& Elsevier]

Abstract: The epidermis of skin is the first line of defense against the environment. A three dimensional model of human skin was used to investigate tissue-specific phenotypes induced by the environmental contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Continuous treatment of organotypic cultures of human keratinocytes with TCDD resulted in intracellular spaces between keratinocytes of the basal and immediately suprabasal layers as well as thinning of the basement membrane, in addition to the previously reported hyperkeratinization. These tissue remodeling events were preceded temporally by changes in expression of the extracellular matrix degrading enzyme, matrix metalloproteinase-10 (MMP-10). In organotypic cultures MMP-10 mRNA and protein were highly induced following TCDD treatment. Q-PCR and immunoblot results from TCDD-treated monolayer cultures, as well as indirect immunofluorescence and immunoblot analysis of TCDD-treated organotypic cultures, showed that MMP-10 was specifically contributed by the epidermal keratinocytes but not the dermal fibroblasts. Keratinocyte-derived MMP-10 protein accumulated over time in the dermal compartment of organotypic cultures. TCDD-induced epidermal phenotypes in organotypic cultures were attenuated by the keratinocyte-specific expression of tissue inhibitor of metalloproteinase-1, a known inhibitor of MMP-10. These studies suggest that MMP-10 and possibly other MMP-10-activated MMPs are responsible for the phenotypes exhibited in the basement membrane, the basal keratinocyte layer, and the cornified layer of TCDD-treated organotypic cultures. Our studies reveal a novel mechanism by which the epithelial–stromal microenvironment is altered in a tissue-specific manner thereby inducing structural and functional pathology in the interfollicular epidermis of human skin. [Copyright &y& Elsevier]

Highlights: [•] Oocytes of X. tropicalis oocytes present an outwardly-rectifying Cl− current. [•] This current may be partially attributed to the expression of the TMEM16A channel. [•] Five alternatively spliced isoforms of TMEME16A were identified and expressed in HEK-293 cells. [•] The TMEM16A isoforms are widely expressed in different tissues. [Copyright &y& Elsevier]

Highlights: [•] New series of pyrrolizine derivatives were designed and synthesized. [•] All compounds were evaluated as anticancer agents against a panel of cell lines. [•] Compounds 12b and 14b–d were the most potent with IC50 values <2.73μM. [•] The tested ligands exhibited an ability to activate caspase-3/7. [Copyright &y& Elsevier]

The aim of this study was to prepare and characterize cholesterol-poly(ethylene) glycol (chol-PEG) nanocarriers of two different molecular weights (1 and 5 kDa) and to determine their effect on the transscleral retention and permeation of a lipophilic multi-therapeutic agent, sirolimus (rapamycin), with potential application in angiogenic and immunogenic ocular diseases. Sirolimus-containing nanocarriers were prepared using the thin-film hydration method and characterized for their physicochemical properties including size, drug entrapment (EE) and loading (DL) efficiencies, stability, surface charge, morphology, critical micelle concentration (CMC) and thermal properties. Ussing chambers were used to determine the retention and permeability of sirolimus-containing nanocarriers in porcine sclera followed by ultrastructural tissue examination. Sirolimus-containing nanocarriers had an average size of 11.7 nm (chol-PEG 1 kDa) and 13.8 nm (chol-PEG 5 kDa) and zeta potentials of 0.41 and −1.05, respectively. Both nanocarriers had similar transscleral permeabilities (chol-PEG 1 kDa 6.44 × 10−7 and 5 kDa 6.16 × 10−7 cm2 s−1), and very high scleral retention compared with a free solution of sirolimus (chol-PEG 1 kDa 16.9 μg/g; chol-PEG 5 kDa 7.48 μg/g; free sirolimus 0.57 μg/g). The DL (EE) for chol-PEG 1 and 5 kDa were 2.93% (77.4%) and 3.10% (81.6%), respectively. The CMC values for the nanocarriers were similar to those previously reported in literature (3.85 × 10−7 M for chol-PEG 1 kDa; 4.26 × 10−7 M for chol-PEG 5 kDa). In conclusion, chol-PEG nanocarriers successfully loaded sirolimus and resulted in scleral permeation and high retention, which shows potential utility for the topical delivery of lipophilic ocular drugs. [ABSTRACT FROM AUTHOR]

Abstract: Cigarette smoking is a key factor for the development and progression of different cancers including mammary tumor in women. Resveratrol (Res) is a promising natural chemotherapeutic agent that regulates many cellular targets including p21, a cip/kip family of cyclin kinase inhibitors involved in DNA damage-induced cell cycle arrest and blocking of DNA replication and repair. We have recently shown that cigarette smoke condensate (CSC) prepared from commercially available Indian cigarette can cause neoplastic transformation of normal breast epithelial MCF-10A cell. Here we studied the mechanism of Res mediated apoptosis in CSC transformed (MCF-10A-Tr) cells in vitro and in vivo. Res mediated apoptosis in MCF-10A-Tr cells was a p21 dependent event. It increased the p21 protein expression in MCF-10A-Tr cells and MCF-10A-Tr cells-mediated tumors in xenograft mice. Res treatment reduced the tumor size(s) and expression of anti-apoptotic proteins (e.g. PI3K, AKT, NFκB) in solid tumor. The expressions of cell cycle regulatory (Cyclins, CDC-2, CDC-6, etc.), BER associated (Pol-β, Pol-δ, Pol-ε, Pol-η, RPA, Fen-1, DNA-Ligase-I, etc.) proteins and LP-BER activity decreased in MCF-10A-Tr cells but remain significantly unaltered in isogenic p21 null MCF-10A-Tr cells after Res treatment. Interestingly, no significant changes were noted in SP-BER activity in both the cell lines after Res exposure. Finally, it was observed that increased p21 blocks the LP-BER in MCF-10A-Tr cells by increasing its interaction with PCNA via competing with Fen-1 after Res treatment. Thus, Res caused apoptosis in CSC-induced cancer cells by reduction of LP-BER activity and this phenomenon largely depends on p21. [Copyright &y& Elsevier]

Abstract: The study aimed to determine the effect of 3′,4′-dihydroxyflavonol (DiOHF) on mitochondrial function, in particular opening of the mitochondrial permeability transition pore (mPTP), respiratory function and reactive oxygen species (ROS) production, in isolated cardiac mitochondria after coronary artery occlusion and reperfusion in vivo. Opening of the mPTP, oxygen consumption and ROS production (assessed by measurement of H2O2) was determined in mitochondria isolated from normal hearts or from the ischemic zone of rat hearts subjected to 30min coronary artery occlusion and 15min reperfusion. Treatment of sham rats with DiOHF (10mgkg−1 iv) significantly increased the concentration of Ca2+ required to stimulate mPTP opening. This was accompanied by increased state 3 oxygen consumption and decreased H2O2 release. Ischemia and reperfusion (IR) significantly decreased the concentration of Ca2+ required to stimulate mPTP opening, decreased state 3 oxygen consumption and increased H2O2 release, when pyruvate plus malate was provided as a substrate. Treatment with DiOHF prevented IR-induced changes in mPTP opening, state 3 oxygen consumption and H2O2 release so that there was no difference compared to sham. In isolated cardiac mitochondria from normal rats DiOHF had no effect on mPTP opening or on state 3 respiration but caused a small increase in state 4 respiration and decreased the respiratory control ratio. DiOHF, administered during ischemia just before reperfusion, inhibits mPTP opening and preserves mitochondrial function through a mechanism likely to be independent of its antioxidant activity or any direct effect on the mPTP. [Copyright &y& Elsevier]

Abstract: The role of endoplasmic reticulum (ER) stress in pregnancy remains largely unknown. Pregnant mice were subcutaneously administered tunicamycin (Tun), an ER stressor, as a single dose [0, 50, and 100μg Tun/kg/body weight (BW)] on gestation days (GDs) 8.5, 12.5, and 15.5. A high incidence (75%) of preterm delivery was observed only in the group treated with Tun 100μg/kg BW at GD 15.5, indicating that pregnant mice during late gestation are more susceptible to ER stress on preterm delivery. We further examined whether prolonged in utero exposure to ER stress affects fetal development. Pregnant mice were subcutaneously administered a dose of 0, 20, 40, and 60μg Tun/kg from GD 12.5 to 16.5. Tun treatment decreased the placental and fetal weights in a dose-dependent manner. Histological evaluation showed the formation of a cluster of spongiotrophoblast cells in the labyrinth zone of the placenta of Tun-treated mice. The glycogen content of the fetal liver and placenta from Tun-treated mice was lower than that from control mice. Tun treatment decreased mRNA expression of Slc2a1/glucose transporter 1 (GLUT1), which is a major transporter for glucose, but increased placental mRNA levels of Slc2a3/GLUT3. Moreover, maternal exposure to Tun resulted in a decrease in vascular endothelial growth factor receptor-1 (VEGFR-1), VEGFR-2, and placental growth factor. These results suggest that excessive and exogenous ER stress may induce functional abnormalities in the placenta, at least in part, with altered GLUT and vascular-related gene expression, resulting in low infant birth weight. [Copyright &y& Elsevier]

Highlights: [•] Anaerobic metabolism of rebaudiosides A, B, D, and M was evaluated. [•] Pooled human fecal homogenates from males and females used as source of metabolism. [•] Metabolism to steviol of all rebaudiosides was complete after 24h incubation. [•] Safety data on other steviol glycosides are relevant to rebaudiosides B, D, and M. [Copyright &y& Elsevier]

Abstract: Recent reports suggest that N-methyl-d-aspartate receptor (NMDAR) blockade by MK-801 decreases tumor growth. Thus, we investigated whether other ionotropic glutamate receptor (iGluR) antagonists were also able to modulate the proliferation of melanoma cells. On the other hand, the antiestrogen tamoxifen (TAM) decreases the proliferation of melanoma cells, and is included in combined therapies for melanoma. As the efficacy of TAM is limited by its metabolism, we investigated the effects of the NMDAR antagonist MK-801 in combination with TAM and its active metabolites, 4-hydroxytamoxifen (OHTAM) and endoxifen (EDX). The NMDAR blockers MK-801 and memantine decreased mouse melanoma K1735-M2 cell proliferation. In contrast, the NMDAR competitive antagonist APV and the AMPA and kainate receptor antagonist NBQX did not affect cell proliferation, suggesting that among the iGluR antagonists only the NMDAR channel blockers inhibit melanoma cell proliferation. The combination of antiestrogens with MK-801 potentiated their individual effects on cell biomass due to diminished cell proliferation, since it decreased the cell number and DNA synthesis without increasing cell death. Importantly, TAM metabolites combined with MK-801 promoted cell cycle arrest in G1. Therefore, the data obtained suggest that the activity of MK-801 and antiestrogens in K1735-M2 cells is greatly enhanced when used in combination. [Copyright &y& Elsevier]

Highlights: [•] Rapamycin enhances mitophagy via increasing p62 translocation to the mitochondria. [•] Rapamycin attenuates brain ischemic damage and improves mitochondrial function. [•] The protection of rapamycin to mitochondrial is linked to enhanced mitophagy. [ABSTRACT FROM AUTHOR]

Abstract: Chronic intermittent hypoxia (CIH) is an underlying component of obstructive sleep apnoea and has been shown to have deleterious and damaging effects on central neurons and to impair synaptic plasticity in the CA1 region of the rat hippocampus. CIH has previously been shown to impair synaptic plasticity and working memory. CIH is a potent inducer of hypoxia inducible factor (HIF), a key regulator in a cell's adaptation to hypoxia that plays an important role in the fate of neurons during ischemia. Levels of HIF-1α are regulated by the activity of a group of enzymes called HIF-prolyl 4-hydroxylases (PHDs) and these have become potential pharmacological targets for preconditioning against ischemia. However little is known about the effects of prolyl hydroxylase inhibition and CIH on synaptic transmission and plasticity in sub-regions of the hippocampus. Male Wistar rats were treated for 7-days with either saline, CIH or PHD inhibition (dimethyloxaloylglycine, DMOG; 50mg/kg, i.p.). At the end of treatment all three groups showed no change in synaptic excitability using paired pulse paradigms. However long-term potentiation (LTP) was impaired in the CA1 region of the hippocampus in both CIH and DMOG treated animals. LTP induced in the dentate gyrus was not significantly affected by either CIH or DMOG treatment. We also investigated the effect of 7-day CIH and DMOG treatment on the recovery of synaptic transmission following an acute 30min hypoxic insult. CIH treated animals showed an improved rate of recovery of synaptic transmission following re-oxygenation in both the CA1 and the dentate gyrus. These results suggest that LTP induction in the CA1 region is more sensitive to both CIH and DMOG treatments than the dentate gyrus. [Copyright &y& Elsevier]

Pharmacological inhibition of matrix metalloproteinase-2 (MMP-2) is a promising target for acute cardioprotection against ischemia/reperfusion injury. Therefore, here we investigated if the MMP inhibitor ilomastat administered either before ischemia or before reperfusion is able to reduce infarct size via inhibition of MMP-2, the most abundant MMP in the rat heart. Infarct-size limiting effect of ilomastat (0.3–6.0μmol/kg) was tested in an in vivo rat model of myocardial infarction induced by 30min coronary occlusion/120min reperfusion. Ilomastat at 0.75 and 1.5μmol/kg decreased infarct size significantly as compared to the vehicle-treated (dimethyl sulfoxide) group (from 66.1±4.6% to 45.3±7.0% and 46.7±5.5% of area at risk, p <0.0.5, respectively), when administered 5min before the onset of ischemia. Ilomastat at 6.0μmol/kg significantly reduced infarct size from its control value of 65.4±2.5% to 52.8±3.7% of area at risk (p <0.05), when administered 5min before the onset of reperfusion. Area at risk was not significantly affected by ilomastat treatments. To further assess the cytoprotective effect of ilomastat, primary cardiomyocytes isolated from neonatal rats were subjected to 240min simulated ischemia followed by 120min simulated reperfusion in the presence of ilomastat (5nM–5μM). Ilomastat at 500nM and 5μM significantly increased cell viability when compared to vehicle treated group. To assess the in situ MMP-2 inhibitory effect of ilomastat, in separate experiments in situ zymography was performed in cardiomyocytes. The cytoprotective concentration of ilomastat (500nM) showed a moderate (approximately 25%) inhibition of intracellular MMP-2 in ischemic/reperfused cardiomyocytes. In these cells, MMP-2 immunostaining showed a 90% colocalization with the in situ gelatinolytic activity. We conclude that the MMP inhibitor ilomastat reduces infarct size when administered either before the onset of ischemia or before the onset of reperfusion in vivo. Furthermore, this is the first demonstration that a moderate inhibition of intracellular MMP-2 is sufficient to confer cardiocytoprotection. [ABSTRACT FROM AUTHOR]

Highlights: [•] Blockade of Notch signaling increased reactive oxygen species (ROS) in primary HUVECs. [•] Abruption of ROS generation abolished Notch blockade-induced HUVEC proliferation, migration and adhesion. [•] The enhanced generation of ROS after blocking Notch signal was accompanied by augmented expression of Nox4. [•] Increased expression of Nox4 led to enhanced phosphorylation of VEGFR2 and ERK in HUVECs. [Copyright &y& Elsevier]

Abstract: The aryl hydrocarbon receptor (AhR) is an important mediator of toxic responses after exposure to xenobiotics including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and dioxin-like polychlorinated biphenyls (PCBs). Activation of AhR responsive genes requires AhR dimerization with the aryl hydrocarbon receptor nuclear translocator (ARNT), a heterodimeric partner also shared by the hypoxia-inducible factor-1α (HIF-1α) protein. TCDD-stimulated AhR transcriptional activity can be influenced by hypoxia; however, it less well known whether hypoxia interferes with AhR transcriptional transactivation in the context of PCB-mediated AhR activation in human cells. Elucidation of this interaction is important in liver hepatocytes which extensively metabolize ingested PCBs and experience varying degrees of oxygen tension during normal physiologic function. This study was designed to assess the effect of hypoxia on AhR transcriptional responses after exposure to 3,3′,4,4′,5-pentachlorobiphenyl (PCB 126). Exposure to 1% O2 prior to PCB 126 treatment significantly inhibited CYP1A1 mRNA and protein expression in human HepG2 and HaCaT cells. CYP1A1 transcriptional activation was significantly decreased upon PCB 126 stimulation under conditions of hypoxia. Additionally, hypoxia pre-treatment reduced PCB 126 induced AhR binding to CYP1 target gene promoters. Importantly, ARNT overexpression rescued cells from the inhibitory effect of hypoxia on XRE-luciferase reporter activity. Therefore, the mechanism of interference of the signaling crosstalk between the AhR and hypoxia pathways appears to be at least in part dependent on ARNT availability. Our results show that AhR activation and CYP1A1 expression induced by PCB 126 were significantly inhibited by hypoxia and hypoxia might therefore play an important role in PCB metabolism and toxicity. [Copyright &y& Elsevier]

Highlights: [•] Anthraquinones quinizarin and danthron unwind negatively supercoiled DNA. [•] Anthraquinones quinizarin and danthron lengthen linear DNA. [•] Anthraquinones quinizarin and danthron possess middle binding affinity to DNA. [•] Anthraquinones quinizarin and danthron interact with DNA by intercalating mode. [Copyright &y& Elsevier]

Highlights: [•] A new HBV-susceptible cell line, designated HepG2-hNTCP-C4, was established. [•] Pretreatment with 3% DMSO facilitated HBV infection into HepG2-hNTCP-C4 cells. [•] HBV infection into HepG2-hNTCP-C4 cells was mediated by NTCP. [•] HBV infection was blocked by a neutralizing antibody and by NTCP inhibitors. [•] Chemical screening identified oxysterols as inhibitors of HBV infection. [ABSTRACT FROM AUTHOR]

Highlights: [•] We show anisomycin (ANS) induces cell death in drug-resistant breast cancer cells. [•] We identify death-inducing ANS analogues. [•] Our data do not fit the current model for ANS-induced cell death. [•] We propose that a ribosome-ANS complex is a death signal or ANS has an unknown target. [Copyright &y& Elsevier]

Abstract: Aqueous mixtures of defatted corn starch and palmitic acid were heated and high pressure homogenized in order to form amylose inclusion complexes. The effects of homogenization pressure (0–120 MPa) and palmitic acid concentration (0.5–8% based on starch content) on starch-palmitic acid complex formation as well as on complex index, X-ray diffraction, thermal properties, viscosity and particle size were investigated. Complex index increased with an increase in the amount of palmitic acid and homogenization pressure, and reached a maximum value (about 60%) when the fatty acid content was 4% and the homogenization pressure was 100 MPa. X-ray diffraction patterns indicated the formation of V-helical complexes between starch and palmitic acid. This technology could prospectively be used in prepared starch-lipid complexes. [Copyright &y& Elsevier]

Abstract: Carbon monoxide (CO) releasing molecules (CO-RMs) have been shown to inhibit growth of commensal Escherichia coli (E. coli). In the present study we examined the effect of CORM-2 on uropathogenic E. coli (UPEC) that produces extended-spectrum β-lactamase (ESBL). Viability experiments showed that CORM-2 inhibited the growth of several different ESBL-producing UPEC isolates and that 500 μM CORM-2 had a bactericidal effect within 4 h. The bactericidal effect of CORM-2 was significantly more pronounced than the effect of the antibiotic nitrofurantoin. CORM-2 demonstrated a low level of cytotoxicity in eukaryotic cells (human bladder epithelial cell line 5637) at the concentrations and time-points where the antibacterial effect was obtained. Real-time RT-PCR studies of different virulence genes showed that the expression of capsule group II kpsMT II and serum resistance traT was reduced and that some genes encoding iron acquisition systems were altered by CORM-2. Our results demonstrate that CORM-2 has a fast bactericidal effect against multiresistant ESBL-producing UPEC isolates, and also identify some putative UPEC virulence factors as targets for CORM-2. CO-RMs may be candidate drugs for further studies in the field of finding new therapeutic approaches for treatment of uropathogenic ESBLproducing E. coli. [Copyright &y& Elsevier]

Highlights: [•] S. cervi is widely used as a model to screen antifilarials. [•] Polyphenol rich EtOH extract of A. indica leaves were optimized by RSM. [•] EEA was tested against mf and adults of S. cervi cultured in vitro. [•] Morphological, molecular and biochemical alterations were examined. [•] Apoptosis and ROS up regulation are the probable cause of effectiveness. [ABSTRACT FROM AUTHOR]

Highlights: [•] Chenopodium ambrosioides oil showed potential antileishmanial activity. [•] Chenopodium oil caused better selectivity compared with its major components. [•] Products cause a breakdown of mitochondrial membrane potential and redox indexes. [•] Oil showed effect against Plasmodium falciparum and Trypanosoma brucei. [ABSTRACT FROM AUTHOR]

Abstract: Early detection of drug-induced cholestasis remains a challenge during drug development. We have developed and validated a biorelevant sandwich-cultured hepatocytes- (SCH) based model that can identify compounds causing cholestasis by altering bile acid disposition. Human and rat SCH were exposed (24–48h) to known cholestatic and/or hepatotoxic compounds, in the presence or in the absence of a concentrated mixture of bile acids (BAs). Urea assay was used to assess (compromised) hepatocyte functionality at the end of the incubations. The cholestatic potential of the compounds was expressed by calculating a drug-induced cholestasis index (DICI), reflecting the relative residual urea formation by hepatocytes co-incubated with BAs and test compound as compared to hepatocytes treated with test compound alone. Compounds with clinical reports of cholestasis, including cyclosporin A, troglitazone, chlorpromazine, bosentan, ticlopidine, ritonavir, and midecamycin showed enhanced toxicity in the presence of BAs (DICI≤0.8) for at least one of the tested concentrations. In contrast, the in vitro toxicity of compounds causing hepatotoxicity by other mechanisms (including diclofenac, valproic acid, amiodarone and acetaminophen), remained unchanged in the presence of BAs. A safety margin (SM) for drug-induced cholestasis was calculated as the ratio of lowest in vitro concentration for which was DICI≤0.8, to the reported mean peak therapeutic plasma concentration. SM values obtained in human SCH correlated well with reported % incidence of clinical drug-induced cholestasis, while no correlation was observed in rat SCH. This in vitro model enables early identification of drug candidates causing cholestasis by disturbed BA handling. [Copyright &y& Elsevier]

Abstract: The abuse of herbal products containing synthetic cannabinoids has become an issue of public concern. The purpose of this paper was to evaluate the acute cytotoxicity of synthetic cannabinoids on mouse brain neuronal cells. Cytotoxicity induced by synthetic cannabinoid (CP-55,940, CP-47,497, CP-47,497-C8, HU-210, JWH-018, JWH-210, AM-2201, and MAM-2201) was examined using forebrain neuronal cultures. These synthetic cannabinoids induced cytotoxicity in the forebrain cultures in a concentration-dependent manner. The cytotoxicity was suppressed by preincubation with the selective CB1 receptor antagonist AM251, but not with the selective CB2 receptor antagonist AM630. Furthermore, annexin-V-positive cells were found among the treated forebrain cells. Synthetic cannabinoid treatment induced the activation of caspase-3, and preincubation with a caspase-3 inhibitor significantly suppressed the cytotoxicity. These synthetic cannabinoids induced apoptosis through a caspase-3-dependent mechanism in the forebrain cultures. Our results indicate that the cytotoxicity of synthetic cannabinoids towards primary neuronal cells is mediated by the CB1 receptor, but not by the CB2 receptor, and further suggest that caspase cascades may play an important role in the apoptosis induced by these synthetic cannabinoids. In conclusion, excessive synthetic cannabinoid abuse may present a serious acute health concern due to neuronal damage or deficits in the brain. [Copyright &y& Elsevier]

Abstract: Human induced pluripotent stem cell (iPSC)-derived cardiomyocytes show promise for screening during early drug development. Here, we tested a hypothesis that in vitro assessment of multiple cardiomyocyte physiological parameters enables predictive and mechanistically-interpretable evaluation of cardiotoxicity in a high-throughput format. Human iPSC-derived cardiomyocytes were exposed for 30min or 24h to 131 drugs, positive (107) and negative (24) for in vivo cardiotoxicity, in up to 6 concentrations (3nM to 30uM) in 384-well plates. Fast kinetic imaging was used to monitor changes in cardiomyocyte function using intracellular Ca2+ flux readouts synchronous with beating, and cell viability. A number of physiological parameters of cardiomyocyte beating, such as beat rate, peak shape (amplitude, width, raise, decay, etc.) and regularity were collected using automated data analysis. Concentration–response profiles were evaluated using logistic modeling to derive a benchmark concentration (BMC) point-of-departure value, based on one standard deviation departure from the estimated baseline in vehicle (0.3% dimethyl sulfoxide)-treated cells. BMC values were used for cardiotoxicity classification and ranking of compounds. Beat rate and several peak shape parameters were found to be good predictors, while cell viability had poor classification accuracy. In addition, we applied the Toxicological Prioritization Index (ToxPi) approach to integrate and display data across many collected parameters, to derive “cardiosafety” ranking of tested compounds. Multi-parameter screening of beating profiles allows for cardiotoxicity risk assessment and identification of specific patterns defining mechanism-specific effects. These data and analysis methods may be used widely for compound screening and early safety evaluation in drug development. [Copyright &y& Elsevier]

Abstract: Oxidative stress and reactive oxygen species (ROS) have been implicated in the teratogenicity of methanol (MeOH) in rodents, both in vivo and in embryo culture. We explored the ROS hypothesis further in vivo in pregnant C57BL/6J mice. Following maternal treatment with a teratogenic dose of MeOH, 4g/kg via intraperitoneal (ip) injection on gestational day (GD) 12, there was no increase 6h later in embryonic ROS formation, measured by 2′,7′-dichlorodihydrofluorescin diacetate (DCFH-DA) fluorescence, despite an increase observed with the positive control ethanol (EtOH), nor was there an increase in embryonic oxidatively damaged DNA, quantified as 8-oxo-2′-deoxyguanosine (8-oxodG) formation. MeOH teratogenicity (primarily ophthalmic anomalies, cleft palate) also was not altered by pre- and post-treatment with varying doses of the free radical spin trapping agent alpha-phenyl-N-tert-butylnitrone (PBN). In contrast, pretreatment with l-buthionine-(S,R)-sulfoximine (BSO), an inhibitor of glutathione (GSH) synthesis, depleted maternal hepatic and embryonic GSH, and enhanced some new anomalies (micrognathia, agnathia, short snout, fused digits, cleft lip, low set ears), but not the most common teratogenic effects of MeOH (ophthalmic anomalies, cleft palate) in this strain. These results suggest that ROS did not contribute to the teratogenic effects of MeOH in this in vivo mouse model, in contrast to results in embryo culture from our laboratory, and that the protective effect of GSH in this model may arise from its role as a cofactor for formaldehyde dehydrogenase in the detoxification of formaldehyde. [Copyright &y& Elsevier]

Abstract: Acetaminophen (APAP) hepatotoxicity is the leading cause of acute liver failure in the US. Although many aspects of the mechanism are known, recent publications suggest that gap junctions composed of connexin32 function as critical intercellular communication channels which transfer cytotoxic mediators into neighboring hepatocytes and aggravate liver injury. However, these studies did not consider off-target effects of reagents used in these experiments, especially the gap junction inhibitor 2-aminoethoxy-diphenyl-borate (2-APB). In order to assess the mechanisms of protection of 2-APB in vivo, male C56Bl/6 mice were treated with 400mg/kg APAP to cause extensive liver injury. This injury was prevented when animals were co-treated with 20mg/kg 2-APB and was attenuated when 2-APB was administered 1.5h after APAP. However, the protection was completely lost when 2-APB was given 4–6h after APAP. Measurement of protein adducts and c-jun-N-terminal kinase (JNK) activation indicated that 2-APB reduced both protein binding and JNK activation, which correlated with hepatoprotection. Although some of the protection was due to the solvent dimethyl sulfoxide (DMSO), in vitro experiments clearly demonstrated that 2-APB directly inhibits cytochrome P450 activities. In addition, JNK activation induced by phorone and tert-butylhydroperoxide in vivo was inhibited by 2-APB. The effects against APAP toxicity in vivo were reproduced in primary cultured hepatocytes without use of DMSO and in the absence of functional gap junctions. We conclude that the protective effect of 2-APB was caused by inhibition of metabolic activation of APAP and inhibition of the JNK signaling pathway and not by blocking connexin32-based gap junctions. [Copyright &y& Elsevier]

Highlights: [•] Two novel alanyl aminopeptidases identified as immunogenic antigens. [•] Cytoplasmically-located, puromycin-sensitive, but not developmentally-regulated. [•] Down-regulation by RNAi results in slightly reduced growth rate in vitro. [Copyright &y& Elsevier]

Abstract: It is well established that estrogen-like environmental chemicals interact with the ligand-binding site of estrogen receptors (ERs) to disrupt transcriptional control of estrogen responsive targets. Here we investigate the possibility that estrogens also impact splicing decisions on estrogen responsive genes, such as that encoding ERα itself. Targeted PCR cloning was applied to identify six ERα mRNA variants in zebrafish. Sequencing revealed alternate use of transcription and translation start sites, multiple exon deletions, intron retention and alternate polyadenylation. As determined by quantitative (q)PCR, N-terminal mRNA variants predicting long (ERαL) and short (ERαS) isoforms were differentially expressed by tissue-type, sex, stage of development and estrogen exposure. Whereas ERαL mRNA was diffusely distributed in liver, brain, heart, eye, and gonads, ERαS mRNA was preferentially expressed in liver (female>male) and ovary. Neither ERαL nor ERαS transcripts varied significantly during development, but 17β-estradiol selectively increased accumulation of ERαS mRNA (∼170-fold by 120hpf), an effect mimicked by bisphenol-A and diethylstilbestrol. Significantly, a C-truncated variant (ERαS-Cx) lacking most of the ligand binding and AF-2 domains was transcribed exclusively from the short isoform promoter and was similar to ERαS in its tissue-, stage- and estrogen inducible expression. These results support the idea that promoter choice and alternative splicing of the esr1 gene of zebrafish are part of the autoregulatory mechanism by which estrogen modulates subsequent ERα expression, and further suggest that environmental estrogens could exert some of their toxic effects by altering the relative abundance of structurally and functionally distinct ERα isoforms. [Copyright &y& Elsevier]

Abstract: Brans of 23 traditional and 12 improved (both red and white) rice varieties in Sri Lanka were screened for anti-amylase and anti-glycation activities in vitro. Varieties which showed the highest inhibitory activities at screening were further investigated for anti-glucosidase and glycation reversing as anti-diabetic properties. The same varieties were studied for selected antioxidant properties. Significantly high anti-amylase and anti-glycation activities were observed for bran extracts of red varieties compared to white varieties at screening. Traditional red rice varieties, Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti, exhibited significant and dose dependent anti-amylase, anti-glycation and glycation reversing activities. These varieties also showed marked antioxidant properties. It is concluded that brans of Sri Lankan traditional red rice varieties Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti may be potential food supplements for diabetes. [Copyright &y& Elsevier]

Abstract: The identification of “stay-green” in sorghum and its positive correlation with yield increases has encouraged attempts to incorporate “stay-green”-like traits into the genomes of other commercially important cereal crops. However, knowledge on the effects of “stay-green” expression on grain quality under extreme physiological stress is limited. This study examines impacts of “stay-green”-like expression on starch biosynthesis in barley (Hordeum vulgare L.) grain under mild, severe, and acute water stress conditions induced at anthesis. The proportions of long amylopectin branches and amylose branches in the grain of Flagship (a cultivar without “stay-green”-like characteristics) were higher at low water stress, suggesting that water stress affects starch biosynthesis in grain, probably due to early termination of grain fill. The changes in long branches can affect starch properties, such as the rates of enzymatic degradation, and hence its nutritional value. By contrast, grain from the “stay-green”-like cultivar (ND24260) did not show variation in starch molecular structure under the different water stress levels. The results indicate that the cultivar with “stay-green”-like traits has a greater potential to maintain starch biosynthesis and quality in grain during drought conditions, making the “stay-green”-like traits potentially useful in ensuring food security. [Copyright &y& Elsevier]

Abstract: Since the introduction of angiogenesis as a useful target for cancer therapy, few agents have been approved for clinical use due to the rapid development of resistance. This problem can be minimized by simultaneous targeting of multiple angiogenesis signaling pathways, a potential strategy in cancer management known as polypharmacology. The current study aimed at exploring the anti-angiogenic activity of OSU-A9, an indole-3-carbinol-derived pleotropic agent that targets mainly Akt–nuclear factor-kappa B (NF-κB) signaling which regulates many key players of angiogenesis such as vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs). Human umbilical vein endothelial cells (HUVECs) were used to study the in vitro anti-angiogenic effect of OSU-A9 on several key steps of angiogenesis. Results showed that OSU-A9 effectively inhibited cell proliferation and induced apoptosis and cell cycle arrest in HUVECs. Besides, OSU-A9 inhibited angiogenesis as evidenced by abrogation of migration/invasion and Matrigel tube formation in HUVECs and attenuation of the in vivo neovascularization in the chicken chorioallantoic membrane assay. Mechanistically, Western blot, RT-PCR and ELISA analyses showed the ability of OSU-A9 to inhibit MMP-2 production and VEGF expression induced by hypoxia or phorbol-12-myristyl-13-acetate. Furthermore, dual inhibition of Akt–NF-κB and mitogen-activated protein kinase (MAPK) signaling, the key regulators of angiogenesis, was observed. Together, the current study highlights evidences for the promising anti-angiogenic activity of OSU-A9, at least in part through the inhibition of Akt–NF-κB and MAPK signaling and their consequent inhibition of VEGF and MMP-2. These findings support OSU-A9's clinical promise as a component of anticancer therapy. [Copyright &y& Elsevier]

Highlights: [•] The genotoxic potential of BioPQQ™ was evaluated in a battery of genotoxicity tests. [•] BioPQQ™ did not display mutagenic properties in a reverse bacterial mutation assay. [•] BioPQQ™ tested negative in an in vitro chromosomal aberration test in human peripheral blood lymphocytes. [•] BioPQQ™ showed no genotoxic activity in an in vivo micronucleus assay in mice. [ABSTRACT FROM AUTHOR]

Abstract: Changes in mitochondrial ATP synthesis can affect the function of tumor cells due to the dependence of the first step of glycolysis on mitochondrial ATP. The oxidative phosphorylation (OXPHOS) system is responsible for the synthesis of approximately 90% of the ATP in normal cells and up to 50% in most glycolytic cancers; therefore, inhibition of the electron transport chain (ETC) emerges as an attractive therapeutic target. We studied the effect of a lipophilic isoprenylated catechol, 3-hydroxybakuchiol (3-OHbk), a putative ETC inhibitor isolated from Psoralea glandulosa. 3-OHbk exerted cytotoxic and anti-proliferative effects on the TA3/Ha mouse mammary adenocarcinoma cell line and induced a decrease in the mitochondrial transmembrane potential, the activation of caspase-3, the opening of the mitochondrial permeability transport pore (MPTP) and nuclear DNA fragmentation. Additionally, 3-OHbk inhibited oxygen consumption, an effect that was completely reversed by succinate (an electron donor for Complex II) and duroquinol (electron donor for Complex III), suggesting that 3-OHbk disrupted the electron flow at the level of Complex I. The inhibition of OXPHOS did not increase the level of reactive oxygen species (ROS) but caused a large decrease in the intracellular ATP level. ETC inhibitors have been shown to induce cell death through necrosis and apoptosis by increasing ROS generation. Nevertheless, we demonstrated that 3-OHbk inhibited the ETC and induced apoptosis through an interaction with Complex I. By delivering electrons directly to Complex III with duroquinol, cell death was almost completely abrogated. These results suggest that 3-OHbk has antitumor activity resulting from interactions with the ETC, a system that is already deficient in cancer cells. [Copyright &y& Elsevier]

Abstract: The endocrine-disrupting potential of pesticides is of health concern, since they are found ubiquitously in the environment and in food items. We investigated in vitro effects on estrogen receptor (ER) and androgen receptor (AR) transactivity, and aromatase enzyme activity, of the following pesticides: 2-methyl-4-chlorophenoxyacetic acid (MCPA), terbuthylazine, iodosulfuron-methyl-sodium, mesosulfuron-methyl, metsulfuron-methyl, chlormequat chloride, bitertanol, propiconazole, prothioconazole, mancozeb, cypermethrin, tau fluvalinate, malathion and the metabolite ethylene thiourea (ETU). The pesticides were analyzed alone and in selected mixtures. Effects of the pesticides on ER and AR function were assessed in human breast carcinoma MVLN cells and hamster ovary CHO-K1 cells, respectively, using luciferase reporter gene assays. Effects on aromatase enzyme activity were analyzed in human choriocarcinoma JEG-3 cells, employing the classical [3H]2O method. Five pesticides (terbuthylazine, propiconazole, prothioconazole, cypermethrin and malathion) weakly induced the ER transactivity, and three pesticides (bitertanol, propiconazole and mancozeb) antagonized the AR activity in a concentration-dependent manner. Three pesticides (terbuthylazine, propiconazole and prothioconazole) weakly induced the aromatase activity. In addition, two mixtures, consisting of three pesticides (bitertanol, propiconazole, cypermethrin) and five pesticides (terbuthylazine, bitertanol, propiconazole, cypermethrin, malathion), respectively, induced the ER transactivity and aromatase activity, and additively antagonized the AR transactivity. In conclusion, our data suggest that currently used pesticides possess endocrine-disrupting potential in vitro which can be mediated via ER, AR and aromatase activities. The observed mixture effects emphasize the importance of considering the combined action of pesticides in order to assure proper estimations of related health effect risks. [Copyright &y& Elsevier]

Abstract: Cellular mechanisms play a role in conversion of the normal prion protein PrPC to the disease-associated protein PrPSc. The cells provide not only PrPC, but also still largely undefined factors required for efficient prion replication. Previously, we have observed that interference with ERK and p38-JNK MAP kinase pathways has opposing effects on the formation of prions indicating that the process is regulated by a balance in intracellualar signaling pathways. In order to obtain a “flow-chart” of such pathways, we here studied the activation of MEK/ERK and mTORC1 downstream targets in relation to PrPSc accumulation in GT1-1 cells infected with the RML or 22L prion strains. We show that inhibition of mTORC1 with rapamycin causes a reduction of PrPSc accumulation at similar low levels as seen when the interaction between the translation initiation factors eIF4E and eIF4G downstream mTORC1 is inhibited using 4EGI-1. No effect is seen following the inhibition of molecules (S6K1 and Mnk1) that links MEK/ERK signaling to mTORC1-mediated control of translation. Instead, stimulation (high [KCl] or [serum]) or inhibition (MEK-inhibitor) of prion formation is associated with increased or decreased phosphorylation of the neuronal transcription factor Elk1, respectively. This study shows that prion formation can be modulated by translational initiating factors, and suggests that MEK/ERK signaling plays a role in the conversion of PrPC to PrPSc via an Elk1-mediated transcriptional control. Altogether, our studies indicate that prion protein conversion is under the control of intracellular signals, which hypothetically, under certain conditions may elicit irreversible responses leading to progressive neurodegenerative diseases. [Copyright &y& Elsevier]

Highlights: [•] Our aim was to evaluate the effects of avermectin on pigeon neurons in vitro. [•] Morphologic, biochemical and molecular hallmarks of apoptosis was observed. [•] This is first report from apoptosis of avermectin on bird neurons in vitro. [Copyright &y& Elsevier]

Abstract: Objectives: The present study investigates the potential role of hypoxia in maintaining stem cell-like properties and therapeutic resistance in K562 leukemic cell. Methods: Western blot, flow cytometry and cell viability assays were used to investigate the effects of hypoxia (1% O2) on cell proliferation, drug resistance and expression of the hypoxia inducible factor-2α (HIF-2α), the octamer-binding transcription factor 4 (Oct4), CD133, CD34 and the ATP-binding cassette sub-family G member 2 (ABCG2) as well as Smad2 phosphorylation in the drug resistant cell line K562/DOX and its parental cell line. Results: Hypoxia induced growth inhibition and significantly upregulated HIF-2α, CD133, Oct4, CD34 and ABCG2 expression in the wild type K562 cells (p<0.05). The IC50 of doxorubicin was also enhanced about 2.5-fold in hypoxia. In contrast, the K562/DOX cells, which showed significantly higher ABCG2 expression and IC50 for various drugs, no significant difference in cell proliferation was observed between hypoxia and normoxia. The hypoxia-induced upregulation of HIF-2α, CD133, Oct4, CD34 and ABCG2 expression was significantly lower than in the wild type cells (p<0.05). Moreover, hypoxia induced the phosphorylation of Smad2 and additional treatment with SD-208, an inhibitor of the TGF-β receptor I kinase, resulted in a dose-dependent downregulation of CD133 and Oct4 in the K562/DOX cells. Conclusions: Hypoxia plays an important role in enhancing the stem cell-like properties and to induce multidrug resistance of leukemia cells. The activation of the TGF-β/Smad2 signaling pathway may be involved in the regulation of this pathophysiological process. [Copyright &y& Elsevier]

Abstract: Since the inflammatory response and oxidative stress are involved in the stroke cascade, we evaluated here the effects of Phycocyanobilin (PCB, the C-Phycocyanin linked tetrapyrrole) on PC12 cell survival, the gene expression and the oxidative status of hypoperfused rat brain. After the permanent bilateral common carotid arteries occlusion (BCCAo), the animals were treated with saline or PCB, taking samples 24h post-surgery. Global gene expression was analyzed with GeneChip Rat Gene ST 1.1 from Affymetrix; the expression of particular genes was assessed by the Fast SYBR Green RT-PCR Master Mix and Bioplex methods; and redox markers (MDA, PP, CAT, SOD) were evaluated spectrophotometrically. The PCB treatment prevented the H2O2 and glutamate induced PC12 cell injury assessed by the MTT assay, and modulated 190 genes (93 up- and 97 down-regulated) associated to several immunological and inflammatory processes in BCCAo rats. Furthermore, PCB positively modulated 19 genes mostly related to a detrimental pro-inflammatory environment and counteracted the oxidative imbalance in the treated BCCAo animals. Our results support the view of an effective influence of PCB on major inflammatory mediators in acute cerebral hypoperfusion. These results suggest that PCB has a potential to be a treatment for ischemic stroke for which further studies are needed. [Copyright &y& Elsevier]

Abstract: Although mangiferin which is a naturally occurring glucosylxanthone has exhibited promising anticancer activities, the detailed molecular mechanism of mangiferin on cancers still remains enigmatic. In this study, the anticancer activity of mangiferin was evaluated in breast cancer cell line-based in vitro and in vivo models. We showed that mangiferin treatment resulted in decreased cell viability and suppression of metastatic potential in breast cancer cells. Further mechanistic investigation revealed that mangiferin induced decreased matrix metalloproteinase (MMP)-7 and -9, and reversal of epithelial–mesenchymal transition (EMT). Moreover, it was demonstrated that mangiferin significantly inhibited the activation of β-catenin pathway. Subsequent experiments showed that inhibiting β-catenin pathway might play a central role in mangiferin-induced anticancer activity through modulation of MMP-7 and -9, and EMT. Consistent with these findings in vitro, the antitumor potential was also verified in mangiferin-treated MDA-MB-231 xenograft mice where significantly decreased tumor volume, weight and proliferation, and increased apoptosis were obtained, with lower expression of MMP-7 and -9, vimentin and active β-catenin, and higher expression of E-cadherin. Taken together, our study suggests that mangiferin might be used as an effective chemopreventive agent against breast cancer. [Copyright &y& Elsevier]

Highlights: [•] We determined the first crystal structure of DHBPS of Gram-positive bacteria, S. pneumoniae, with 2.0Å resolution. [•] We first revealed that SpDHBPS showed activity in the presence of the trivalent metal ion, Fe3+. [ABSTRACT FROM AUTHOR]

Highlights: [•] Aβ fibrillar seed can interact with monomer Aβ at the stoichiometry of 1:2. [•] Aβ fibrillar seed can accelerate fibrils formation and reduce higher-molecular-weight oligomer level and its lifespan. [•] Aβ fibrillar seeds are found to be able to rescue neuronal cells from Aβ cytotoxicity. [ABSTRACT FROM AUTHOR]

Highlights: [•] The unicellular red alga Cyanidioschyzon merolae is insensitive to rapamycin. [•] Expression of yeast FKBP12 in C. merolae made this alga rapamycin-susceptible. [•] Rapamycin inhibited TOR kinase activity dependent of the exogenous FKBP12. [•] Functional analysis system of TOR kinase was established in C. merolae. [ABSTRACT FROM AUTHOR]