Myocardial Matrix Hydrogels Mitigate Negative Remodeling and Improve Function in Right Heart Failure Model.

This study evaluates the effectiveness of myocardial matrix (MM) hydrogels in mitigating negative right ventricular (RV) remodeling in a rat model of RV heart failure. The goal was to assess whether a hydrogel derived from either the right or left ventricle could promote cardiac repair. Injured rat right ventricles were injected with either RV-or left ventricular-derived MM hydrogels. Both hydrogels improved RV function and morphology and reduced negative remodeling. This study supports the potential of injectable biomaterial therapies for treating RV heart failure.

Designing of new tetrahydro-ß-carboline-based ABCG2 inhibitors using 3D-QSAR, molecular docking, and DFT tools.

Human ATP-binding cassette superfamily G member 2 (ABCG2) protein is a member of the ABC transporter family, which is responsible for multidrug resistance (MDR) in cancerous cells. MDR reduces the effectiveness of chemotherapy in breast cancer, which is one of the leading causes of death in women globally. MDR in cancer cells is one of the immediate signs of progression of resistance; thus, various anticancer drugs can be designed. To reduce MDR, we utilized the tetrahydro-ß-carboline (THßC) compound library. We accomplished a three-dimensional quantitative structure-activity relationship (3D-QSAR), scaffold hopping to design a new library of compounds of THßC, and further molecular docking, induced-fit docking (IFD), molecular mechanics energies combined with generalized born and surface area continuum solvation (MM-GBSA), drug-like features, ADMET properties, and density functional theory (DFT) studies were performed. From these studies, the best 3D-QSAR model (r2 = 0.99, q2 = 0.92) was found, and the necessity of electrostatic, steric, and hydrophobic field effects were determined that could modulate bioactivity. Moreover, based on electrostatic, steric, and hydrophobic field notations, new THßC derivatives (3409) were designed. These findings might provide new insight for researchers to perform in vitro and in vivo studies for better antagonists against MDR in treating breast cancer.Communicated by Ramaswamy H. Sarma.

Genomic and Epigenomic Features of Glioblastoma Multiforme and its Biomarkers.

Glioblastoma multiforme is a serious and life-threatening tumor of central nervous system, characterized by aggressive behavior, poor prognosis, and low survival rate. Despite of the availability of aggressive antitumor therapeutic regimen for glioblastoma (radiotherapy followed by chemotherapeutic dose), recovery rate, and patients' survival ratio is attributed to the lack of selectivity of therapeutic drugs and less advancement in cancer therapeutics over last decade. Moreover, tools employed in conventional diagnosis of glioblastoma are more invasive and painful, making the process excruciating for the patients. These challenges urge for the need of novel biomarkers for diagnosis, prognosis, and prediction purpose with less invasiveness and more patient compliance. This article will explore the genetic biomarkers isocitrate dehydrogenase mutation, MGMT mutations, and EGFR that can be deployed as an analytical tool in diagnosis of disease and prognosis of a therapeutic course. The review also highlights the importance of employing novel microRNAs as prognostic biomarkers. Recent clinical advancements to treat GBM and to prevent relapse of the disease are also discussed in this article in the hope of finding a robust and effective method to treat GBM.

Glutathione S-transferase gene polymorphism and asthma: a case-control study in a pediatric population.

Aim: To carry out a case-control study of the association of GST gene polymorphisms in pediatric asthma-related oxidative stress. Materials & methods: Asthma patients (n = 250) and age-matched healthy subjects (n = 250) DNA were genotyped for GSTM1/GSTT1 (+/+, +/-, -/+ and -/-) frequencies using multiplex-PCR and plasma oxidative stress markers (examined spectrophotometrically). Results: Asthma patients had significantly more common null-genotype GSTM1-/GSTT1- (10.4%; p = 0.002) and elevated levels of malondialdehyde, protein carbonyl and 8-hydroxy-2-deoxyguanosine as compared with controls. In addition, the level of plasma glutathione, GST activity and ferric-reducing ability were significantly decreased as compared with controls. Conclusion: Our data revealed significant associations between GSTM1-/GSTT1- genotype and oxidative stress markers in asthmatic children, which may very likely contribute to increased incidence of bronchial asthma.

Dopamine inhibits human CD8+ Treg function through D1-like dopaminergic receptors.

CD8+ T regulatory/suppressor cells (Treg) affect peripheral tolerance and may be involved in autoimmune diseases as well as in cancer. In view of our previous data showing the ability of DA to affect adaptive immune responses, we investigated the dopaminergic phenotype of human CD8+ Treg as well as the ability of DA to affect their generation and activity. Results show that CD8+ T cells express both D1-like and D2-like dopaminergic receptors (DR), tyrosine hydroxylase (TH), the rate-limiting enzyme in the synthesis of DA, and vesicular monoamine transporter (VMAT) 2 and contain high levels of intracellular DA. Preferential upregulation of DR mRNA levels in the CD8+CD28- T cell compartment occurs during generation of CD8+ Treg, which is reduced by DA and by the D1-like DR agonist SKF-38393. DA and SKF-38393 also reduce the suppressive activity of CD8+ Treg on human peripheral blood mononuclear cells. Treg are crucial for tumor escape from the host immune system, thus the ability of DA to inhibits Treg function supports dopaminergic pathways as a druggable targets to develop original and innovative antitumor strategies.

Involvement of Glutathione Depletion in Selective Cytotoxicity of Oridonin to p53-Mutant Esophageal Squamous Carcinoma Cells.

Oridonin, a diterpenoid compound isolated from traditional Chinese medicine Rabdosia rubescens, has shown antitumor effects to esophageal cancer. However, its molecular mechanism is not fully understood, which limits its clinical application. In the present study, we used RNA-seq analysis to check the transcriptome changes after oridonin treatment and we found genes controlling the GSH-ROS system were up-regulated, namely SLC7A11, TXNRD1, TRIM16, SRXN1, GCLM, and GCLC. Furthermore, our data suggest that oridonin significantly increased the production of ROS in EC109 and TE1 cells, which can be inhibited by NAC. Interestingly, oridonin can dramatically reduce intracellular GSH levels in TE1 cells in a concentration and time-dependent manner. In addition, cell death caused by oridonin was strongly inhibited by GSH (1 mM), while GSSG (1 mM) had little effect. At the same time, we also found that oridonin showed selective cytotoxicity to esophageal squamous carcinoma cell with p53 mutation since mut-p53 cells had lower SLC7A11 expression, a component of the cystine/glutamate antiporter. We also found that γ-glutamyl cysteine synthetase inhibitor (BSO) synergizes with oridonin to strongly inhibit EC109 cells at a low dose. These results suggested that the antitumor effects of oridonin are based on its -SH reactivity and glutathione depletion. Esophageal squamous carcinoma cells with p53-mutation showed hypersensitivity to oridonin because of the suppression of SLC7A11 expression by p53 mutation.

Regulation of the DNA Repair Complex during Somatic Hypermutation and Class-Switch Recombination.

B lymphocytes optimize Ab responses by somatic hypermutation (SH), which introduces point mutations in the variable regions of the Ab genes and by class-switch recombination (CSR), which changes the expressed C region exon of the IgH. These Ab diversification processes are initiated by the deaminating enzyme activation-induced cytidine deaminase followed by many DNA repair enzymes, ultimately leading to deletions and a high mutation rate in the Ab genes, whereas DNA lesions made by activation-induced cytidine deaminase are repaired with low error rate on most other genes. This indicates an advanced regulation of DNA repair. In this study, we show that initiation of Ab diversification in B lymphocytes of mouse spleen leads to formation of a complex between many proteins in DNA repair. We show also that BCR activation, which signals the end of successful SH, reduces interactions between some proteins in the complex and increases other interactions in the complex with varying kinetics. Furthermore, we show increased localization of SH- and CSR-coupled proteins on switch regions of the Igh locus upon initiation of SH/CSR and differential changes in the localization upon BCR signaling, which terminates SH. These findings provide early evidence for a DNA repair complex or complexes that may be of functional significance for carrying out essential roles in SH and/or CSR in B cells.

Propoxur-induced oxidative DNA damage in human peripheral blood mononuclear cells: protective effects of curcumin and α-tocopherol.

The present study enumerates the attenuating effects of curcumin and α-tocopherol against propoxur induced oxidative DNA damage in human peripheral blood mononuclear cells (PBMC). Cultured cells were isolated from peripheral blood of healthy volunteers, and were exposed to varying concentrations of propoxur (0-21 µg/ml) for 6, 12, and 24 h, and in combination with curcumin (9.2 µg/ml) or α-tocopherol (4.3 µg/ml) or both. Cytotoxic effect of propoxur was examined by MTT assay. The role of oxidative stress beneath the cytotoxicity of propoxur was evaluated by the measurement of reduced glutathione (GSH), malondialdehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OH-dG) levels in cell lysate. A concentration-dependent cell death, depletion of GSH, an increase in the level of both MDA and 8-OH-dG were observed. Co-treatment with curcumin or α-tocopherol significantly attenuates depleted GSH, decrease in MDA and 8-OH-dG levels in propoxur exposed cells (p < 0.05). The results of the present study provide experimental evidence of involvement of oxidative stress in propoxur-mediated genotoxicity in human PBMC and highlight the antioxidant role of curcumin and α-tocopherol following propoxur exposure.

A modular gain-of-function approach to generate cortical interneuron subtypes from ES cells.

Whereas past work indicates that cortical interneurons (cINs) can be generically produced from stem cells, generating large numbers of specific subtypes of this population has remained elusive. This reflects an information gap in our understanding of the transcriptional programs required for different interneuron subtypes. Here, we have utilized the directed differentiation of stem cells into specific subpopulations of cortical interneurons as a means to identify some of these missing factors. To establish this approach, we utilized two factors known to be required for the generation of cINs, Nkx2-1 and Dlx2. As predicted, their regulated transient expression greatly improved the differentiation efficiency and specificity over baseline. We extended upon this "cIN-primed" model in order to establish a modular system whereby a third transcription factor could be systematically introduced. Using this approach, we identified Lmo3 and Pou3f4 as genes that can augment the differentiation and/or subtype specificity of cINs in vitro.

Role of pesticides in the induction of tumor angiogenesis.

Due to their estrogen-mimicking ability, pesticides are considered as prime etiological suspects of increasing tumor incidence, although a direct link is still undefined. The present study aimed to identify the effect of xenoestrogens (lindane, propoxur and endosulfan) at 20 mg/l each on tumorigenesis, by evaluating endothelial cell proliferation, H(3) thymidine incorporation, wound healing, ascites formation and secretion, shell less Chorio Allantoic Membrane (CAM) formation using in vitro, as well as in vivo, models. The genotoxic effect of xenoestrogens in terms of DNA damage was also studied. The results showed that the endothelial cell proliferation, H(3) thymidine incorporation, wound healing, CAM formation were increased following xenoestrogen exposure, but the intensity of angiogenesis was dependent on the structural homology of these xenoestrogens to endogenous estrogen. Moreover, lindane was the most potent angiogenesis stimulator followed by propoxur and Endosulfan. Further studies were undertaken to examine lindane for its possible carcinogenicity. However, no effect was observed on the integrity of DNA after exposure to these xenoestrogens.

Possible role of superantigens in inducing autoimmunity in pemphigus patients.

The diagnostic and pathological relevance of anti-desmoglein autoantibodies in common forms of pemphigus has been well established, and T cells have been shown to play a role in the onset and progression of these diseases. The role of superantigens in provoking polyclonal activation of T cells with many different fine specificities, possibly including autoreactive T cells and T-cell mediated autoantibody response, is unknown. Further, abnormal T-cell function may lead to opportunistic infections particularly with Candida. The response of T cells of pemphigus patients to recall antigens of these opportunists is not clear. The aim of this study was to investigate the in vitro response of T lymphocytes from pemphigus patients to common bacterial superantigens such as streptococcal pyrogenic exotoxin A and staphylococcal enterotoxin B, and recall antigens such as Candida antigen. Changes in CD3(+) CD4(+) and CD3(+) CD8(+) T-cell sub-populations and expression of naive/memory markers (CD45RA(+) /RO(+)) on different T cells were analyzed by flow cytometry. Significant elevation in CD3(+) CD4(+) and expression of the memory (CD45RO(+)) markers on these cells was observed both in pemphigus vulgaris and pemphigus foliaceus patients, as compared to healthy controls, upon stimulation with streptococcal pyrogenic exotoxin A and staphylococcal enterotoxin B. However, only memory T cells (CD45RO(+)) were significantly increased upon Candida antigen stimulation. Our study suggests that CD4(+) memory T lymphocytes may modulate the pathogenic autoantibody response in pemphigus patients, and also emphasizes the possibility that the superantigen-reactive T cells participate in the triggering of autoimmunity in pemphigus.

Pulmonary function and oxidative stress in workers exposed to styrene in plastic factory: occupational hazards in styrene-exposed plastic factory workers.

Styrene is a volatile organic compound used in factories for synthesis of plastic products. The pneumotoxicity of styrene in experimental animals is known. The aim of the present study was to study the effect of styrene on lung function and oxidative stress in occupationally exposed workers in plastic factory. Thirty-four male workers, between 18 and 40 years of age, exposed to styrene for atleast 8 hours a day for more than a year were studied, while 30 age- and sex-matched healthy subjects not exposed to styrene served as controls. Assessment of lung functions showed a statistically significant reduction (p < 0.05) in most of the lung volumes, capacities (FVC, FEV(1), VC, ERV, IRV, and IC) and flow rates (PEFR, MEF(75%), and MVV) in the study group (workers) as compared to controls. Malondialdehyde (MDA) was observed to be significantly high (p < 0.05) while ferric-reducing ability of plasma (FRAP) was significantly low (p < 0.05) in styrene-exposed subjects. Reduced glutathione (GSH) level was significantly depleted in exposed subjects as compared to control group. The mean value of serum cytochrome c in styrene-exposed subjects was found to be 1.1 ng/ml (0.89-1.89) while in control its levels were under detection limit (0.05 ng/ml). It shows that styrene inhalation by workers leads to increased level of oxidative stress, which is supposed to be the cause of lung damage.

Intra uterine growth retardation: association with organochlorine pesticide residue levels and oxidative stress markers.

Intra uterine growth retardation (IUGR) is a major complication of pregnancy, affecting ∼5% to 10% of newborns. Hexachlorocyclohexane (HCH) is an organochlorine pesticide that consists of eight stereoisomers and γ-isomer is the only isomer that possesses insecticidal activity. The aim of the present study was to analyze the OCP residues in maternal and cord blood of women and to assess the level of oxidative stress markers as well as to establish correlation with OCP levels. Fifty women delivering neonates with low birth weight (IUGR) and equal number of women delivering normal birth weight babies (control) were recruited. We have observed higher levels of γ-HCH and T-HCH and increased oxidative stress markers in IUGR subjects versus control subjects. Significant correlations were also found between HCH isomers and oxidative stress markers in IUGR subjects. In conclusion, our results suggest that higher levels of HCH isomers may be associated with IUGR and increased oxidative stress.

Ameliorating effect of N-acetylcysteine and curcumin on pesticide-induced oxidative DNA damage in human peripheral blood mononuclear cells.

Endosulfan, malathion, and phosphamidon are widely used pesticides. Subchronic exposure to these contaminants commonly affects the central nervous system, immune, gastrointestinal, renal, and reproductive system. There effects have been attributed to increased oxidative stress. This study was conducted to examine the role of oxidative stress in genotoxicity following pesticide exposure using peripheral blood mononuclear cells (PBMC) in vitro. Further possible attenuation of genotoxicity was studied using N-acetylcysteine (NAC) and curcumin as known modulators of oxidative stress. Cultured mononuclear cells was isolated from peripheral blood of healthy volunteers, and exposed to varying concentrations of different pesticides: endosulfan, malathion, and phosphamidon for 6, 12, and 24 h. Lipid peroxidation was assessed by cellular malondialdehyde (MDA) level and DNA damage was quantified by measuring 8-hydroxy-2'-deoxyguanosine (8-OH-dG) using ELISA. Both MDA and 8-OH-dG were significantly increased in a dose-dependent manner following treatment with these pesticides. There was a significant decrease in MDA and 8-OH-dG levels in PBMC when co-treated with NAC or/and curcumin as compared to pesticide alone. These results indicate that pesticide-induced oxidative stress is probably responsible for the DNA damage, and NAC or curcumin attenuate this effect by counteracting the oxidative stress.

Assessment of phosphamidon-induced apoptosis in human peripheral blood mononuclear cells: protective effects of N-acetylcysteine and curcumin.

The molecular mechanism for noncholinergic toxicity of phosphamidon, an extensively used organophosphate pesticide, is still not clear. The aim of the present study is to find the possible molecular mechanism of this pesticide to induce apoptosis and the role of different drugs for attenuation of such effects. Human peripheral blood mononuclear cells (PBMC) were incubated with increasing concentrations of phosphamidon (0-20 µM) for 6-24 h. The MTT assay reveals that phosphamidon induces cytotoxicity in a dose-dependent manner. Cellular glutathione (GSH) is depleted in a dose-dependent manner from 55% to 70% at concentrations between 10 and 20 µM. The percentage of cells that bind to Annexin-V, which is a representative of cells either undergoing apoptosis or necrosis during 24 h incubation, increases in a dose-dependent manner. Above 5 µM, significant necrosis of cells was observed. DNA fragmentation assay revealed that at low concentration of phosphamidon (1 µM), no appreciable change in DNA fragmentation was seen; however, distinct fragmentation was observed beyond 2.5 µM. Phosphamidon was found to cause significant depletion of GSH, which correlates well with the percentage of cells undergoing apoptosis. An increasing trend in levels of cytochrome c was observed with increasing concentration of phosphamidon, indicating that the apoptotic effect of phosphamidon is mediated through cytochrome c release. Coadministration of the antioxidants N-acetylcysteine and curcumin attenuated phosphamidon-induced apoptosis. This further supports our hypothesis that oxidative stress, as indicated by GSH depletion, results in the induction of apoptosis by release of cytochrome c.

Association of glutathione S-transferase M1 and T1 gene polymorphisms and oxidative stress markers in preterm labor.

OBJECTIVE: Oxidative stress and related gene polymorphism may be associated with the etiology of preterm labor (PTL). The present study was designed to investigate association of GSTM1 and GSTT1 gene polymorphisms with PTL and their relationship with oxidative stress markers. DESIGN AND METHODS: Sixty cases of PTL and sixty three subjects of full term labor (FTL) were included in the study. Multiplex PCR was performed for GSTM1 and GSTT1 genes polymorphism and oxidative stress markers were analyzed. RESULT: MDA and 8-OHdG levels were increased, while GSH was decreased in PTL than FTL subjects. Frequency of GSTM1-/GSTT1-(null) was significantly higher in PTL in comparison to FTL (p=0.028, OR=3.4). Subjects with GSTM1-/GSTT1+, GSTM1+/GSTT1-, GSTM1-/GSTT1- have significant differences of oxidative stress markers as compared to GSTM1+/GSTT1+ genotype. CONCLUSION: GSTM1-/GSTT1- (null) genotype may be one of the associated genetic factor for the increased risk of PTL.

Organochlorine pesticide residue levels and oxidative stress in preterm delivery cases.

A number of studies have focused attention on various biochemical abnormalities evoked due to exposure to organochlorine pesticides (OCPs). The aim of the present study was to analyze the OCP residues in maternal and cord blood of women and assess the levels of different non-enzymatic oxidative stress markers as well as to establish correlation with OCP levels, if any. Thirty women in each group of full-term delivery (FTD; > or =37 weeks of gestation) and preterm delivery (PTD; <37 weeks of gestation) were enrolled in this study. Levels of OCPs like Hexachlorocyclohexane (HCH), endosulfan, p,p(') Dichlorodiphenyldichloroethylene (DDE) and p,p' Dichlorodiphenyltrichloroethane (DDT) were analyzed by gas chromatography. Non-enzymatic oxidative stress was measured by the quantification of malondialhyde (MDA), protein carbonyl, reduced glutathione (GSH) and ferric-reducing ability of plasma (FRAP). MDA and protein carbonyl levels were increased significantly, while the levels of GSH and FRAP were decreased in PTD in comparison to FTD cases. We have observed higher levels of beta-HCH and alpha-endosulfan and increased oxidative stress in PTD than FTD cases. In PTD cases, a significant positive correlation was observed between maternal blood levels of beta-HCH and MDA (r = .78), beta-HCH and GSH (r = -.65), gamma-HCH and MDA (r = .89), gamma-HCH and GSH (r = -.74) and alpha-endosulfan and MDA (r = .54) in PTD cases. We also found significant correlations between cord blood levels of beta-HCH and MDA (r = .59), beta-HCH and GSH (r = -.69), gamma-HCH and MDA (r = .62) and alpha-endosulfan and MDA (r = .54) in PTD cases. In conclusion, our results suggest that higher levels of some of the OCP residues may be associated with PTD and increased oxidative stress.

Protective effects of different antioxidants against endosulfan-induced oxidative stress and immunotoxicity in albino rats.

Endosulfan exposure (8 and 16 mg/kg) to rats significantly decreased the activities of superoxide dismutase and catalase, level of reduced glutathione and increased lipid peroxidation. The primary and secondary antiSRBC antibody titers, plaque forming cells counts and delayed hypersensivity reaction, and the TH1 or TH2 cytokines levels were significantly suppressed in a dose dependent manner. L-ascorbic acid and alpha-tocopherol produced a synergistic reversal of oxidative stress parameters following endosulfan exposure. N-acetylcysteine produced significant reversal of altered oxidative stress parameters and immune response after endosulfan exposure. A significant attenuation of the oxidative stress markers and immunotoxicity with a combined therapy of L-ascorbic acid plus alpha-tocopherol and with N-acetylcysteine was clearly demonstrated by the present results.