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Background: A recent high-throughput sequencing study revealed an anomalous underexpression of circular RNA UBAP2 (circUBAP2) in acute myocardial infarction (AMI), yet its biological function within this context remains elusive. This study aims to unravel whether circUBAP2 is instrumental in modulating the pathogenesis of AMI and to illuminate the underlying molecular mechanisms at play. Results: circUBAP2 was abnormally low expressed in AMI. Inducing circUBAP2 ameliorated hypoxiainduced myocardial cell injury by enhancing cellular viability, and decreasing lactate dehydrogenase release, apoptosis, inflammation, and oxidative damage. circUBAP2 targeted miR-148b-3p, miR-148b- 3p overexpression offset circUBAP2-induced cardioprotection. Cyclin-dependent kinase inhibitor 1B (CDKN1B) was mediated by miR-148b-3p, and CDKN1B upregulation suppressed the deleterious effect of circUBAP2 silencing on hypoxic AC16 cells. In addition, overexpression of circUBAP2 improved myocardial injury, decreased myocardial cell apoptosis, and alleviated inflammation and oxidative stress in AMI mice. Conclusions: circUBAP2 ameliorates AMI by competitively binding to miR-148b-3p and mediating CDKN1B expression. [ABSTRACT FROM AUTHOR]

The widespread use of pesticides performs a vital role in safeguarding crop yields and quality, providing the opportunity for multiple pesticides to co-exist, which poses a significant potential risk to human health. To assess the toxic effects caused by exposures to individual pesticides (chlorpyrifos, carbofuran and acetamiprid), binary combinations and ternary combinations, individual and combined exposure models were developed using HepG2 cells and the types of combined effects of pesticide mixtures were assessed using concentration addition (CA), independent action (IA) and combination index (CI) models, respectively, and the expression of biomarkers related to oxidative stress, apoptosis and cell necrosis was further examined. Our results showed that both individual pesticides and mixtures exerted toxic effects on HepG2 cells. The CI model indicated that the toxic effects of pesticide mixtures exhibited synergistic effects. The results of the lactate dehydrogenase (LDH) release and apoptosis assay revealed that the pesticide mixture increased the release of LDH and apoptosis levels. Moreover, our results also showed that individual pesticides and mixtures disrupted redox homeostasis and that pesticide mixtures produced more intense oxidative stress effects. In conclusion, we have illustrated the enhanced combined toxicity of pesticide mixtures by in-vitro experiments, which provides a theoretical basis and scientific basis for further toxicological studies.

Ghrelin has been widely recognized as a key peptide in the cardiovascular system. This study detected the potential of ghrelin in MI management and tried to decode one of the possible underlying mechanisms. H9c2 cells were pretreated with ghrelin and were subjected to hypoxia/reoxygenation (H/R). CCK-8, flow cytometry, Western blot and LDH analysis were conducted to assess the changes in cell survival. LY294002 and Compound C were used to treat H9c2 cells for blocking PI3K/AKT and AMPK pathways, respectively. Ghrelin expression in H9c2 cells was suppressed by siRNA-mediated silencing to see the effects of endogenous ghrelin. We found that, following H/R, H9c2 cells viability was decreased, CyclinD1 and CDK4 were down-regulated, apoptosis was induced, the release of LDH was enhanced, and the expression levels of Cox-2 and iNOS were up-regulated. Ghrelin protected H9c2 cells against H/R induced these alterations. Besides, ghrelin activated PI3K/AKT and AMPK pathways even in H/R-stimulated cells. The protective effects of ghrelin against H/R-induced cell damage were all attenuated by the addition of LY294002 or Compound C. Moreover, endogenous inhibition of ghrelin significantly induced cell death of H9c2 cells. In conclusion, this study demonstrated that ghrelin pretreatment protected H9c2 cells against H/R-induced cell damage, possibly via PI3K/AKT and AMPK pathways.

Vascular calcification is common in chronic kidney disease; however, the extent to which such condition can affect the renal microvasculature and the neighboring cell types is unclear. Our induced-calcification model in renal proximal tubular (PT) cells exhibited endoplasmic reticulum (ER) stress and oxidative damage, leading to apoptosis. Here, we utilized such calcification in mouse vascular smooth muscle (MOVAS-1) cells as a vascular calcification model, because it exhibited reactive oxygen species (ROS) generation, ER and oxidative stress, inflammatory, and apoptotic gene expressions. To demonstrate whether the vascular calcification condition can dictate the function of the adjacent PT cell layer, we utilized a Transwell multilayer culture system by combining those MOVAS-1 cells in the bottom chamber and polarized PT cells in the upper chamber to show the dimensional cross-signaling effect. Interestingly, calcification of MOVAS-1 cells, in this co-culture, induced H2O2 and lactate dehydrogenase (LDH) release leading to store-operated Ca2+ entry, ROS generation, and activation of oxidative, inflammatory, and apoptotic gene expressions in PT cells through paracrine signaling. Interestingly, application of tannic acid (TA) to either calcified MOVAS-1 or uncalcified PT cells diminished such detrimental pathway activation. Furthermore, the TA-mediated protection was much higher in the PT cells when applied on the calcified MOVAS-1 cells, and the delayed the pathological effects in neighboring PT cells can well be via paracrine signaling. Together, these results provide evidence of vascular calcification-induced PT cell damage, and the protective role of TA in preventing such pathological consequences, which can potentially be used as a nephroprotective remedy.

Two new alkaloids, named hositisines A (1) and B (2), with two known alkaloids (3 and 4) were isolated from the stems of Ormosia hosiei Hemsl. et Wils. Their structures were confirmed by UV, HRESIMS, NMR spectra. The absolute configurations of 1 and 2 were determined by quantum ECD calculation and ECD, respectively. Compounds 1–3 could significantly reduce the LDH release at the concentration 50 μM, which showed they could strongly protect the PC12 cells exposed to oxygen and glucose deprivation/reoxygenation (OGD/R) injury. [ABSTRACT FROM AUTHOR]

Ghrelin has been widely recognized as a key peptide in the cardiovascular system. This study detected the potential of ghrelin in MI management and tried to decode one of the possible underlying mechanisms. H9c2 cells were pretreated with ghrelin and were subjected to hypoxia/reoxygenation (H/R). CCK-8, flow cytometry, Western blot and LDH analysis were conducted to assess the changes in cell survival. LY294002 and Compound C were used to treat H9c2 cells for blocking PI3K/AKT and AMPK pathways, respectively. Ghrelin expression in H9c2 cells was suppressed by siRNA-mediated silencing to see the effects of endogenous ghrelin. We found that, following H/R, H9c2 cells viability was decreased, CyclinD1 and CDK4 were down-regulated, apoptosis was induced, the release of LDH was enhanced, and the expression levels of Cox-2 and iNOS were up-regulated. Ghrelin protected H9c2 cells against H/R induced these alterations. Besides, ghrelin activated PI3K/AKT and AMPK pathways even in H/R-stimulated cells. The protective effects of ghrelin against H/R-induced cell damage were all attenuated by the addition of LY294002 or Compound C. Moreover, endogenous inhibition of ghrelin significantly induced cell death of H9c2 cells. In conclusion, this study demonstrated that ghrelin pretreatment protected H9c2 cells against H/R-induced cell damage, possibly via PI3K/AKT and AMPK pathways. [ABSTRACT FROM AUTHOR]

Inflammasomes are macromolecular complexes that assemble upon the detection of cytoplasmic pathogen-associated or danger-associated signals and induce a necrotic type of cell death termed pyroptosis, facilitating pro-inflammatory cytokine release. Inflammasomes play a critical role in innate immunity and inflammatory response; however, they have also been associated with multiple diseases, including autoinflammatory and neurodegenerative conditions. In the following chapter, we describe methods to detect inflammasome activation and its downstream effects, including detection of ASC oligomerization, detection of activated caspase-1 and cleaved IL-1β, as well as read-outs for inflammasome-mediated cell death., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

The widespread use of pesticides performs a vital role in safeguarding crop yields and quality, providing the opportunity for multiple pesticides to co-exist, which poses a significant potential risk to human health. To assess the toxic effects caused by exposures to individual pesticides (chlorpyrifos, carbofuran and acetamiprid), binary combinations and ternary combinations, individual and combined exposure models were developed using HepG2 cells and the types of combined effects of pesticide mixtures were assessed using concentration addition (CA), independent action (IA) and combination index (CI) models, respectively, and the expression of biomarkers related to oxidative stress, apoptosis and cell necrosis was further examined. Our results showed that both individual pesticides and mixtures exerted toxic effects on HepG2 cells. The CI model indicated that the toxic effects of pesticide mixtures exhibited synergistic effects. The results of the lactate dehydrogenase (LDH) release and apoptosis assay revealed that the pesticide mixture increased the release of LDH and apoptosis levels. Moreover, our results also showed that individual pesticides and mixtures disrupted redox homeostasis and that pesticide mixtures produced more intense oxidative stress effects. In conclusion, we have illustrated the enhanced combined toxicity of pesticide mixtures by in-vitro experiments, which provides a theoretical basis and scientific basis for further toxicological studies. [Display omitted] • Co-existence of multiple pesticides poses potentially greater risk to human health. • CI model showed that the toxic effects of pesticide mixtures exhibited synergistic effects. • Individual pesticides and mixtures disrupted various biological processes on HepG2 cells. • Pesticide mixtures have a synergistic effect on the expression of multiple biomarkers. [ABSTRACT FROM AUTHOR]

UVA affects epidermal cell physiology in a complex manner, but the harmful effects have been studied mainly in terms of DNA damage, mutagenesis and carcinogenesis. We investigated UVA effects on membrane integrity and antioxidant defense of dysplastic keratinocytes after one and two hours of irradiation, both immediately after exposure, and 24 h post-irradiation. To determine the UVA oxidative stress on cell membrane, lipid peroxidation was correlated with changes in fatty acid levels. Membrane permeability and integrity were assessed by propidium iodide staining and lactate dehydrogenase release. The effects on keratinocyte antioxidant protection were investigated in terms of catalase activity and expression. Lipid peroxidation increased in an exposure time-dependent manner. UVA exposure decreased the level of polyunsaturated fatty acids, which gradually returned to its initial value. Lactate dehydrogenase release showed a dramatic loss in membrane integrity after 2 h minimum of exposure. The cell ability to restore membrane permeability was noted at 24 h post-irradiation (for one hour exposure). Catalase activity decreased in an exposure time-dependent manner. UVA-irradiated dysplastic keratinocytes developed mechanisms leading to cell protection and survival, following a non-lethal exposure. The surviving cells gained an increased resistance to apoptosis, suggesting that their pre-malignant status harbors an abnormal ability to control their fate.

In the present investigation, we identified the phytochemical constituents of total oligomeric flavonoid fraction (TOF) of Cyperus rotundus by LC–ESI-MS/MS and also demonstrated its antihemolytic effects against 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) induced hemolysis of rat erythrocytes. Our results of TOF extract exhibited DPPH, metal chelating, ABTS, NO and hydroxyl radical scavenging activities with an IC 50 values of 23.72 ± 1.6, 52.45 ± 2.88, 9.8 ± 0.42, 6.5 ± 0.33 and 120 ± 6.83 μg/ml respectively, whereas total antioxidant and reducing power activities were 194 ± 12.5 μg GAE/mg extract and 145 ± 8.3 μg AAE/mg extract. The extract showed potent inhibitory activity against AAPH induced plasmid DNA damage, protein oxidation and lipid peroxidation. The TOF extract mitigates AAPH induced hemolysis and exhibits ∼50% antihemolytic activity. TOF pretreatment also preserved morphology of erythrocytes as observed and measured by light microscope and atomic force microscope analysis. Furthermore, the TOF fraction effectively inhibited AAPH induced LDH release, ROS generation and lipid peroxidation. Taken together, our data demonstrate the antihemolytic activity of C. rotundus against AAPH induced oxidative stress of erythrocytes, and was associated with the decrease in oxidative stress, cellular damage and protection of macromolecules. In conclusion, the effects might be correlated with high content of flavonoids and polyphenols identified in C. rotundus . This suggests the clinical application of TOF fraction of C. rotundus against ROS induced cell death. [ABSTRACT FROM AUTHOR]

Decreased cell membrane integrity is a primary pathological change observed in traumatic brain injury (TBI) that activates a number of complex intercellular and intracellular pathological events, leading to further neural injury. In this paper, we assessed the effects of urinary trypsin inhibitor (UTI) on astrocyte membrane integrity by determining the percentage of lactate dehydrogenase (LDH) released after sustained compression injury using a hydrostatic pressure model of mechanical-like TBI. Astrocytes isolated from SD rat pups were injured by sustained compression. At a pressure of 0.3 MPa for 5 min, a significant increase in LDH release was observed compared with control samples. Astrocytes displayed extensive structural disruption of mitochondrial cristae reflected in their swelling. Based on our initial results, injured astrocytes were treated with UTI at a final concentration of 500, 1,000, 3,000 or 5,000 U/ml for 24 h. The percentage of LDH released from injured astrocytes was significantly decreased when 1,000 and 3,000 U/ml of UTI were used. In a separate experiment, astrocytes were treated with UTI at a final concentration of 1,000 U/ml immediately, or at 30 min, 2, 6, or 24 h after sustained compression. The percentage of LDH release was significantly reduced ( P < 0.05) when astrocytes were treated with UTI immediately or 30 min later. Together, our results suggest that UTI may have protective effects on astrocytes injured by sustained compression injury. Furthermore, the early administration (<2 h after injury) of UTI may result in a better outcome compared with delayed administration. [ABSTRACT FROM AUTHOR]

Background: Currently available therapies for Alzheimer's disease (AD) do not treat the underlying cause of AD. Anecdotal observations in nursing homes from multiple studies strongly suggest an inverse relationship between cancer and AD. Therefore, we reasoned that oncology drugs may be effective against AD. Methods: We screened a library of all the FDA-approved oncology drugs and identified bis-chloroethylnitrosourea (BCNU or carmustine) as an effective amyloid beta (Aβ) reducing compound. To quantify Aβ levels, Chinese hamster ovary (CHO) cells stably expressing amyloid precursor protein 751WT (APP751WT) called 7WD10 cells were exposed to different concentrations of BCNU for 48 hours and the conditioned media were collected. To detect Aβ the conditioned media were immunoprecipitated with Aβ9 antibody and subjected to immunoblot detection. Amyloid plaques were quantified in the brains of a mouse model of AD after chronic exposure to BCNU by thoflavin S staining. Results: BCNU decreased normalized levels of Aβ starting from 5 μM by 39% (P < 0.05), 10 μM by 51% (P < 0.01) and 20 μM by 63% (P < 0.01) in CHO cells compared to a control group treated with butyl amine, a structural derivative of BCNU. Interestingly, soluble amyloid precursor protein a (sAPPa) levels were increased to 167% (P < 0.01) at 0.5 μM, 186% (P < 0.05) at 1 μM, 204% (P < 0.01) at 5 μM and 152% (P < 0.05) at 10 μM compared to untreated cells. We also tested the effects of 12 structural derivatives of BCNU on Aβ levels, but none of them were as potent as BCNU. BCNU treatment at 5 μM led to an accumulation of immature APP at the cell surface resulting in an increased ratio of surface to total APP by 184% for immature APP, but no change in mature APP. It is also remarkable that BCNU reduced Aβ generation independent of secretases which were not altered up to 40 μM. Interestingly, levels of transforming growth factor beta (TGFb) were increased at 5 μM (43%, P < 0.05), 10 μM (73%, P < 0.01) and 20 μM (92%, P < 0.001). Most significantly, cell culture results were confirmed in vivo after chronic administration of BCNU at 0.5 mg/kg which led to the reduction of Aβ40 by 75% and amyloid plaque burden by 81%. Conversely, the levels of sAPPα were increased by 45%. Conclusions: BCNU reduces Aβ generation and plaque burden at non-toxic concentrations possibly through altered intracellular trafficking and processing of APP. Taken together these data provided unequivocal evidence that BCNU is a potent secretase-sparing anti-Aβ drug. [ABSTRACT FROM AUTHOR]

UVA affects epidermal cell physiology in a complex manner, but the harmful effects have been studied mainly in terms of DNA damage, mutagenesis and carcinogenesis. We investigated UVA effects on membrane integrity and antioxidant defense of dysplastic keratinocytes after one and two hours of irradiation, both immediately after exposure, and 24 h post-irradiation. To determine the UVA oxidative stress on cell membrane, lipid peroxidation was correlated with changes in fatty acid levels. Membrane permeability and integrity were assessed by propidium iodide staining and lactate dehydrogenase release. The effects on keratinocyte antioxidant protection were investigated in terms of catalase activity and expression. Lipid peroxidation increased in an exposure time-dependent manner. UVA exposure decreased the level of polyunsaturated fatty acids, which gradually returned to its initial value. Lactate dehydrogenase release showed a dramatic loss in membrane integrity after 2 h minimum of exposure. The cell ability to restore membrane permeability was noted at 24 h post-irradiation (for one hour exposure). Catalase activity decreased in an exposure time-dependent manner. UVA-irradiated dysplastic keratinocytes developed mechanisms leading to cell protection and survival, following a non-lethal exposure. The surviving cells gained an increased resistance to apoptosis, suggesting that their pre-malignant status harbors an abnormal ability to control their fate. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrate the cytotoxic potential of the Schiff base iron complex [FeIII(salophene)Cl] in vitro and ex vivo and illustrate its ability to overcome multiple drug resistance in vincristine and daunorubicine resistant leukemic cells (Nalm-6). Treatment of lymphoma cells (BJAB) with [FeIII(salophene)Cl] led to the exclusion of unspecific necrosis, a concentration-dependent inhibition of proliferation and a specific apoptotic cell death. We further detected a significant loss of the mitochondrial membrane potential in lymphoma cells and an up- and downregulation of various apoptosis relevant genes, respectively, indicating the involvement of the intrinsic mitochondrial pathway. [Copyright &y& Elsevier]

The biological effects of a class of oxygenated imidazolium ionic liquids were studied in comparison with alkyl imidazolium salts (BMIM BF4 and BMIM N(CN)2).The cellular and subcellular effects were evaluated on rat pheochromocytoma PC12 cell lines, through MTT test, lactate dehydrogenase release and acetylcholinesterase inhibition; the eco-toxicological responses were assessed through the acute toxicity tests towards Daphnia magna and Vibrio fischeri. The introduction of ethoxy moieties in the lateral chain of imidazolium cations reduced the biological effects in all the tests. The acute toxicity towards D. magna was not affected by the number of ethoxy units, but the crustacean seemed to be sensitive to the type of anion; on the contrary, a further addition of ethoxy moieties increased the toxicity towards V. fischeri, M(OE)4MIM N(CN)2 being the most toxic oxygenated ionic liquid. In the cytotoxicity assays the salts with oxygenated cations resulted ineffective compared to BMIMs, independently from the anion and the number of ethoxy units in the lateral chain. In order to estimate the influence on membrane fluidity, an analysis of fluorescence anisotropy was done and it indicated that BMIM BF4, the most toxic ionic liquid among the tested ones, led to a destabilization of the model membranes at any molarity. [Copyright &y& Elsevier]

Abstract: Purpose: To determine the effect of four marketed multipurpose contact lens solutions (MPSs) on corneal epithelial cell viability. Methods: Comparison of the effect of MPS A (Renu MultiPlus, Bausch & Lomb), MPS B (OPTI-FREE Express, Alcon), MPS C (AQuify, CibaVision), and MPS D (OPTI-FREE RepleniSH, Alcon) on cell viability was performed by quantifying cellular ATP content, resazurin reduction, and lactate dehydrogenase (LDH) release in transformed human corneal epithelial cells (HCEpiC) and primary bovine corneal epithelial cells (BCEpiC). Results: Significant reductions in cellular ATP content were observed at 40% solution and above with both MPS B and MPS D, compared to at 100% only for MPS A and MPS C, and similar results were obtained in BCEpiC. Effects on resazurin reduction were also less in HCEpiC exposed to increasing doses of MPS A and MPS C than in cells exposed to MPS B and MPS D. After 15min, HCEpiC viability measured by both resazurin reduction and cellular ATP levels was significantly lower for cells exposed to MPS B, MPS D, and MPS C, while HCEpiC exposed to MPS A were not affected. MPS B and MPS D reduced cell viability more than MPS A and MPS C over a 2-h time course in both HCEpiC and BCEpiC. Conclusions: Both MPS B and MPS D can cause large decreases in the viability of cultured corneal epithelial cells even with just a 2h exposure at multiple doses. Significant reduction in cell viability is evident at brief 15–30min exposures. In contrast, MPS A and MPS C have significantly less effect on the cell viability of corneal epithelial cells at multiple doses, after these short exposure times. [Copyright &y& Elsevier]

The article presents a study which examines the cytotoxic effects induced in human lung epithelial cell line (A549) by exposure to α-quartz. The study used a fluorescence microscopic analysis of apoptotic morphology and lactate dehydrogenase (LDH) activity discharge for the evaluation. The study claimed that the concentration-time response attests the cytotoxic effects in human lung cells exposed to α-quartz.

Abstract: Polybrominated diphenyl ethers (PBDEs) are an important class of halogenated organic brominated flame retardants. Because of their presence in abiotic and biotic environments widely and their structural similarity to polychlorinated biphenyls (PCBs), concern has been raised on their possible adverse health effects to humans. This study was designed to determine the anti-proliferative, apoptotic properties of decabrominated diphenyl ether (PBDE-209), using a human hepatoma Hep G2 line as a model system. Hep G2 cells were cultured in the presence of PBDE-209 at various concentrations (1.0–100.0μmol/L) for 72h and the percentage of cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The results showed that PBDE-209 inhibited the cells viability in time and concentration-dependent characteristics at concentrations (10.0–100.0μmol/L). We found that anti-proliferative effect of PBDE-209 was associated with apoptosis on Hep G2 cells by determinations of morphological changes, cell cycle and apoptosis. Mechanism study showed that PBDE-209 could increase the generation of intracellular reactive oxygen species (ROS) concentration-dependently. Antioxidant N-acetylcyteine partially inhibited the increase of ROS. The mechanism for its hepatoma-inhibitory effects was the induction of cellular apoptosis through ROS generation. In addition, activity of lactate dehydrogenase (LDH) release increased when the cells incubated with PBDE-209 at various concentrations and times. These results suggested that PBDE-209 had the toxicity activity of anti-proliferation and induction of apoptosis in tumor cells in vitro. [Copyright &y& Elsevier]

Nuclear factor-kappaB (NF-κB) has a dual role in the promotion or attenuation of cell death. Here, we demonstrated the role of NF-κB in the H2O2-induced death of astrocytes. H2O2 evoked the release of lactate dehydrogenase (LDH), a marker of cell death, and concomitantly decreased the DNA binding and transcriptional activity of NF-κB in cultured astrocytes. H2O2-induced astrocyte death was markedly increased by the co-treatment with pyrrolidinedithiocarbamate, an NF-κB inhibitor. Moreover, the elevation of constitutive NF-κB activity by overexpressing p65 NF-κB subunit attenuated H2O2 toxicity, whereas NF-κB inhibition by overexpressing IκB potentiated the toxicity. NF-κB activity and H2O2 cytotoxicity was further found to be dependent on cell density. Compared with astrocytes in low cell density, those in high cell density exhibited a higher constitutive NF-κB activity and a stronger resistance to H2O2 cytotoxicity. These results indicate that the constitutive activity of NF-κB in astrocytes is required for their survival under oxidative stress such as H2O2. [ABSTRACT FROM AUTHOR]

Abstract: Donepezil has a neuroprotective effect against oxygen–glucose deprivation injury and glutamate toxicity in cultured cortical neurons. In this study, we further characterized the neuroprotective properties of donepezil in rat cortical cell cultures using glutamate receptor-specific agonists (N-methyl-d-aspartate (NMDA), alpha-amino-3-hydroxy-5-methylisoxazolepropionate (AMPA) and kainate). Pretreatment with donepezil (1 μM) for 12 h significantly decreased the lactate dehydrogenase (LDH) release in response to NMDA (100 μM) by 43.8%, and reduced the LDH release in response to kainate (100 μM) and AMPA (100 μM) by 11.9% and 7.5% (without statistical significance), respectively. Donepezil appeared to inhibit LDH release in a concentration-dependent manner at 0.1–10 μM. Cortical neurons exposed to NMDA retained a normal morphological appearance in the presence of 10 μM donepezil. In binding assay for glutamate receptors, donepezil at 100 μM only slightly inhibited binding to the glycine and polyamine sites on NMDA receptor complex. On the other hand, 12 h pretreatment with donepezil at 10 and 100 μM significantly decreased the NMDA-induced increase of intracellular calcium concentration ([Ca2+]i). In conclusion, our results show that donepezil has protective activity against NMDA toxicity in cortical neurons, and this neuroprotection seems to be partially mediated by inhibition of the increase of [Ca2+]i. [Copyright &y& Elsevier]

Abstract: This study was designed to determine the anti-proliferative, apoptotic properties of a novel polysaccharide from the loach, Misgurnus anguillicaudatus (MAP), using a human promyelocytic leukemia line (HL-60) as a model system. HL-60 cells were cultured in the presence of MAP at various concentrations (50–800mg/l) for 5 days and the percentage of cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The results showed that MAP inhibited the cells viability in time and concentration-dependent characteristics. We found that anti-proliferative effect of MAP was associated with apoptosis on HL-60 cells by determinations of morphological changes and oligonucleosomal DNA fragments. In addition, the content of nitric oxide (NO) and activity of lactate dehydrogenase (LDH) release increased when the cells incubated with MAP at various concentrations and times. These investigations suggest that the polysaccharide from loach has the function of anti-proliferation and induction of apoptosis in tumor cells in vitro. [Copyright &y& Elsevier]

Fluoromethyl-2,2-difluoro-1-(trifluoromethyl)vinyl ether (FDVE) is a fluorinated alkene formed by degradation of the volatile anesthetic sevoflurane in anesthesia machines. FDVE is nephrotoxic in rats but not humans. Rat FDVE nephrotoxicity is attributed to FDVE glutathione conjugation and bioactivation of subsequent FDVE-cysteine S-conjugates, in part by renal β-lyase. Although FDVE conjugation and metabolism occur in both rats and humans, the mechanism for selective toxicity in rats and lack of effect in humans is incompletely elucidated. This investigation measured FDVE S-conjugate cytotoxicity in cultured human proximal tubular HK-2 cells, and compared this with known cytotoxic S-conjugates. HK-2 cells were incubated with FDVE and its GSH, cysteine S-mercapturic acid, cysteine S-sulfoxide, and mercapturic acid sulfoxide conjugates (0.1–2.7 mM) for 24 h. Cytotoxicity was determined by lactate dehydrogenase (LDH) release, total LDH, and the ability of viable cells to reduce a tetrazolium-based compound (MTT). FDVE was cytotoxic only at concentrations ≥0.9 mM. No increase in LDH release was observed with either FDVE-GSH conjugate. The FDVE-cysteine conjugates S-(1,1-difluoro-2-fluoromethoxy-2-(trifluoromethyl) ethyl)-l-cysteine (DFEC) and (Z)-S-(1-fluoro-2-fluoromethoxy-2-(trifluoromethyl) vinyl)-l-cysteine ((Z)-FFVC) caused significant differences in LDH release and MTT reduction only at 2.7 mM; (Z)-FFVC was slightly more cytotoxic. Both S-(1,1-difluoro-2-fluoromethoxy-2-(trifluoromethyl) ethyl)-l-cysteine sulfoxide (DFEC-SO) and (Z)-N-acetyl-S-(1-fluoro-2-fluoromethoxy-2-(trifluoromethyl) vinyl)-l-cysteine sulfoxide ((Z)-N-Ac-FFVC-SO) caused slightly greater changes in LDH release or total LDH than the corresponding equimolar DFEC and (Z)-N-acetyl-S-(1-fluoro-2-fluoromethoxy-2-(trifluoromethyl) vinyl)-l-cysteine ((Z)-N-Ac-FFVC) conjugates. In contrast to FDVE S-conjugates, S-(1,2-dichlorovinyl)-l-cysteine was markedly cytotoxic, at concentrations as low as 0.1 mM. These results show that human proximal tubular cells are relatively resistant to FDVE and FDVE S-conjugate cytotoxicity. This may partially explain the lack of FDVE nephrotoxicity in humans. [Copyright &y& Elsevier]

Donepezil hydrochloride (donepezil: (±)-2-[(1-benzylpiperidin-4-yl)methyl]-5,6-dimethoxy-indan-1-one monohydrochloride) is a potent acetylcholinesterase inhibitor used for treatment of Alzheimer''s disease. Although acetylcholinesterase inhibitors are used as a symptomatic treatment for Alzheimer''s disease, it is not clear whether or not they are effective against progressive degeneration of neuronal cells. In this study, we investigated the neuroprotective effects of donepezil and other acetylcholinesterase inhibitors used for treatment of Alzheimer''s disease, i.e., galantamine, rivastigmine, and tacrine. As a neurodegenerative model, we used rat cortical neurons exposed to oxygen–glucose deprivation. Lactate dehydrogenase (LDH) released into the culture medium was measured as a marker of neuronal cell damage. First, the effects of donepezil (10 μM) on three different treatment schedules (from 12 h before to 24 h after oxygen–glucose deprivation (pre-12 h), from 1 h before to 24 h after oxygen–glucose deprivation (pre-1 h) and from 1 h after to 24 h after oxygen–glucose deprivation (post-1 h)) were compared. The pre-12-h treatment most effectively inhibited LDH release. The protective effect of donepezil was confirmed morphologically. Next, the effects of donepezil and the other three acetylcholinesterase inhibitors were compared under the pre-12-h treatment condition. Donepezil (0.1, 1, and 10 μM) significantly decreased LDH release in a concentration-dependent manner. However, galantamine (1, 10, and 100 μM), tacrine (0.1, 1, and 10 μM), and rivastigmine (0.1, 1, and 10 μM) did not significantly decrease LDH release. The neuroprotective effect of donepezil was not antagonized by scopolamine or mecamylamine. These results demonstrate that donepezil has a protective effect against oxygen–glucose deprivation-induced injury to rat primary cultured cerebral cortical neurons. Besides, it is suggested that this effect of donepezil is independent of muscarinic cholinergic system and nicotinic cholinergic system. Thus, donepezil is expected to have a protective effect against progressive degeneration of brain neuronal cells in ischemic cerebrovascular disease and Alzheimer''s disease. [Copyright &y& Elsevier]

Lipid peroxidation is one of the main manifestations of oxidative damage and has been found to play an important role in the toxicity and carcinogenicity of many xenobiotics. In the present study, we investigated the possible induction of lipid peroxidation by aluminium in human foreskin fibroblast cultures by assaying the malondialdehyde (MDA) produced inside the cells. The MDA–thiobarbituric acid (TBA) adduct was assayed by HPLC using fluorometric quantification after extraction in n-butanol. Lactate dehydrogenase (LDH) release was used as a marker of aluminium toxicity. MDA production was significantly increased after 24 h incubation with aluminium and paralleled LDH release. Superoxide dismutase (SOD)+catalase and vitamins C and E added in the culture medium as oxygen radical and free radical scavengers were efficient in preventing MDA production by aluminium, indicating that oxidative processes are one of the main pathways whereby this metal induces cytotoxicity. The latter is also largely prevented, thus confirming the link between oxidative stress induced by aluminium and its cytotoxicity in human skin fibroblasts. Human & Experimental Toxicology (2001) 20, 477–481. [ABSTRACT FROM AUTHOR]

Vascular calcification is common in chronic kidney disease; however, the extent to which such condition can affect the renal microvasculature and the neighboring cell types is unclear. Our induced-calcification model in renal proximal tubular (PT) cells exhibited endoplasmic reticulum (ER) stress and oxidative damage, leading to apoptosis. Here, we utilized such calcification in mouse vascular smooth muscle (MOVAS-1) cells as a vascular calcification model, because it exhibited reactive oxygen species (ROS) generation, ER and oxidative stress, inflammatory, and apoptotic gene expressions. To demonstrate whether the vascular calcification condition can dictate the function of the adjacent PT cell layer, we utilized a Transwell multilayer culture system by combining those MOVAS-1 cells in the bottom chamber and polarized PT cells in the upper chamber to show the dimensional cross-signaling effect. Interestingly, calcification of MOVAS-1 cells, in this co-culture, induced H 2 O 2 and lactate dehydrogenase (LDH) release leading to store-operated Ca2+ entry, ROS generation, and activation of oxidative, inflammatory, and apoptotic gene expressions in PT cells through paracrine signaling. Interestingly, application of tannic acid (TA) to either calcified MOVAS-1 or uncalcified PT cells diminished such detrimental pathway activation. Furthermore, the TA-mediated protection was much higher in the PT cells when applied on the calcified MOVAS-1 cells, and the delayed the pathological effects in neighboring PT cells can well be via paracrine signaling. Together, these results provide evidence of vascular calcification-induced PT cell damage, and the protective role of TA in preventing such pathological consequences, which can potentially be used as a nephroprotective remedy. Schematic diagram of dissected kidney showing microvasculature (left) which is replicated in a simplified model with multicellular Transwell system. Enlarged showing proximal tubular (PT) cells (lower right) in response to vascular calcification, causing the release of H 2 O 2 , which induce store-operated Ca2+ entry (SOCE), leading to endoplasmic reticulum (ER) stress and oxidative damage. Application of Tannic acid (lower left) abrogated such ER and oxidative stress induced cell death by lower the SOCE. Tight Junction (TJ). [Display omitted] • Modelling vascular calcification by ROS activation in calcium crystal-ingested vascular smooth muscle cells (MOVAS-1). • Proximal tubular (PT)/MOVAS-1 cells in transwell co-culture to study tubular/vascular calcification induced cross-signaling. • Store-operated Ca2+ entry in PT cells due to vascular calcification as functional crosstalk and its block by Tannic acid. • Protection against vascular calcification-induced PT cell damage by tannic acid via paracrine signaling. • Tannic acid delayed the pathological effects of vascular calcification in neighboring PT cells via anti-ROS mechanism. [ABSTRACT FROM AUTHOR]

• Four octahedral Co(III) complexes were synthesized and characterized. • Partial intercalation with DNA and static quenching with BSA was established. • MTT assay on A549 and MCF-7 cells revealed their anticancer activity • The complexes showed significant microbial activity. • Complex 3 possessed better biological activity than the ligands and other complexes. The present work deals with the synthesis and characterization of four Co(III) complexes derived from 7-hydroxy-4-oxo-4 H -chromene-3-carbaldehyde-4(N)-substituted thiosemicarbazones. Structural confirmation of the complexes 2 and 3 were aided by X-ray crystallographic analysis, which revealed the coordination of azomethine nitrogen, ring carbonyl oxygen and thiol sulfur atoms of the ligands. DNA and Bovine serum albumin (BSA) binding studies brought about the binding ability of the complexes to biomolecules. The binding constant values calculated for the complexes were in the range (0.30–1.19) × 106 M−1 and the mode of interaction was found to be partially intercalative. The mechanism of quenching with BSA was static with quenching constants in the order 1012 M−1s−1. Their antimicrobial profile has been established by testing against four pathogenic bacterial and fungal species. The cytotoxic potential of the complexes were examined against MCF-7 and A549 cells by MTT assay. The IC 50 values of the complexes were less than cisplatin , which indicated their greater activity over the standard drug. In addition, testing on human normal keratinocyte cells HaCaT indicated their non toxic nature. Lactate dehydrogenase (LDH) and Nitric oxide (NO) release assays supported the cytotoxic ability and suggested apoptotic mode of cell death induced by the complexes. [ABSTRACT FROM AUTHOR]

Four binuclear Ni(II) complexes [ [Ni 2 (H-DEAsal-tsc) 2 (μ-dppm)]·2Cl (1) , [Ni 2 (DEAsal-mtsc) 2 (μ-dppm)] (2) , [Ni 2 (DEAsal-etsc) 2 (μ-dppm)] (3) and [Ni 2 (DEAsal-ptsc) 2 (μ-dppm)] (4) ] were synthesized from the ligands namely 4(N , N)-diethylaminosalicylaldehyde-4(N)-thiosemicarbazone [ H 2 - DEAsal-tsc ] H 2 L 1 /4(N , N)-diethylaminosalicylaldehyde-4(N)-methyl thiosemicarbazone [ H 2 - DEAsal-mtsc ] H 2 L 2 /4(N , N)-diethylaminosalicylaldehyde-4(N)-ethyl thiosemicarbazone [ H 2 - DEAsal-etsc ] H 2 L 3 /4(N , N)diethylaminosalicylaldehyde-4(N)-phenyl thiosemicarbazone [ H 2 - DEAsal-ptsc ] H 2 L 4 and 1,1′-bis(diphenylphosphino)methane (dppm) and characterized by a number of spectro analytical techniques. The molecular structure of complexes [Ni 2 (H-DEAsal-tsc) 2 (μ-dppm)]·2Cl (1) and [Ni 2 (DEAsal-ptsc) 2 (μ-dppm)] (4) have been confirmed by single crystal X-ray diffraction studies. The analysis indicated that in complex 1 , the ligand [ H 2 -DEAsal-tsc ] coordinated as monobasic tridentate donor through phenolic oxygen, azomethine nitrogen and thione sulfur atoms. However, in complex 4 , the ligand [ H 2 -DEAsal-ptsc ] behaved as dibasic tridentate donor with thiolate sulfur coordination. Their ability to bind with Calf Thymus Deoxyribonucleic acid (CT-DNA) and Bovine Serum Albumin (BSA) were analysed spectrometrically. Intercalative interaction of the complexes with DNA was confirmed by ethidium bromide (EB) displacement studies and DNA viscosity measurements. The interaction mechanism of the complexes with BSA was found as static. In vitro antiproliferative studies of the ligands and complexes in A549 (human lung carcinoma cancer), MCF-7 (human breast cancer) and HeLa (human cervical cancer) cell lines witnessed significant cytotoxic nature of the complexes with low IC 50 values (in μM) than the standard metallo-drug cisplatin. Further, the results of Lactate Dehydrogenase (LDH) and Nitric oxide (NO) release assays supported the effectiveness of the complexes on the above said cancer cells. Unlabelled Image • Four binuclear Ni(II) Schiff base complexes were synthesized and characterized. • Molecular structures of complexes 1 and 4 were confirmed by crystallographic studies. • Binding with Calf Thymus Deoxyribonucleic acid and Bovine Serum Albumin were analysed. • IC 50 values of complexes were less than cisplatin against A549, MCF-7 and HeLa cells. • Lactate dehydrogenase (LDH) and nitric oxide (NO) release assays were carried out. [ABSTRACT FROM AUTHOR]