Significant Reduction In Expression Research Articles

LcERF2 modulates cell wall metabolism by directly targeting a UDP-glucose-4-epimerase gene to regulate pedicel development and fruit abscission of litchi.

Elucidating the biochemical and molecular basis of premature abscission in fruit crops should help develop strategies to enhance fruit set and yield. Here, we report that LcERF2 contributes to differential abscission rates and responses to ethylene in Litchi chinensis (litchi). Reduced LcERF2 expression in litchi was observed to reduce fruit abscission, concurrent with enhanced pedicel growth and increased levels of hexoses, particularly galactose, as well as pectin abundance in the cell wall. Ecoptic expression of LcERF2 in Arabidopsis thaliana caused enhanced petal abscission, together with retarded plant growth and reduced pedicel galactose and pectin contents. Transcriptome analysis indicated that LcERF2 modulates the expression of genes involved in cell wall modification. Yeast one-hybrid, dual-luciferase reporter and electrophoretic mobility shift assays all demonstrated that a UDP-glucose-4-epimerase gene (LcUGE) was the direct downstream target of LcERF2. This result was further supported by a significant reduction in the expression of the A.thaliana homolog AtUGE2-4 in response to LcERF2 overexpression. Significantly reduced pedicel diameter and enhanced litchi fruit abscission were observed in response to LcUGE silencing. We conclude that LcERF2 mediates fruit abscission by orchestrating cell wall metabolism, and thus pedicel growth, in part by repressing the expression of LcUGE.

LncRNA Gm16410 Mediates PM2.5-Induced Macrophage Activation via PI3K/AKT Pathway.

PM2.5 refers to atmospheric particulate matters with a diameter of less than 2.5 μm. The deposit of PM2.5 in lung cells can cause oxidative stress, leading to changes in macrophage polarity, which can subsequently cause pulmonary inflammation. Long-chain non-coding RNA (lncRNA) is a class of transcripts that regulate biological processes through multiple mechanisms. However, the role of lncRNA in PM2.5-induced lung inflammation has not been established. In this study, the biological effects and associated mechanism of lncRNA in PM2.5-induced change in macrophage polarity were investigated. The lncRNA-mediated PM2.5-induced macrophage inflammation and lung inflammation-associated injury were also determined. Mice were exposed to chronic levels of PM2.5, and changes in the expression of lncRNA in the lung were measured by lncRNA microarray. lncRNAs that showed significant changes in expression in response to PM2.5 were identified. lncRNA showing the biggest change was subjected to further analysis to determine its functional roles and mechanisms with respect to macrophage activation. The result showed that a significant reduction in expression of one lncRNA, identified as lncGm16410, was observed in the lung of mice and RAW264.7 cells following exposure to PM2.5. lncGm16410 suppressed PM2.5-induced macrophage activation via the SRC protein-mediated PI3K/AKT signaling pathway. PM2.5 promoted lung inflammation by downregulating the expression of lncGm16410, enhancing the activation of macrophages. Thus, lncGm16410 might provide new insight into the prevention of PM2.5 injury.

Increased expression of MUSASHI1 in epithelial breast cancer cells is due to down regulation of miR-125b

BackgroundMusashi1 (MSI1) is an oncogenic protein with a crucial role in the proliferation and characteristics of the epithelial cells in breast cancer. The change in expression of MSI1 has a role in solid tumor progression. There are different factors that regulate MSI1 expression in various cancer tissues including microRNAs which are considered as one of the most important of these factors. The aim of our study is identification of the molecular cause of maximal expression of MSI1 in epithelial breast cancer cell lines.ResultsAmong predicted microRNAs, miR-125b, miR-637 and miR-802 were able to significantly reduce the luciferase activity. In addition, the relative expression of these three miRNAs were measured in the cancerous cell lines that results showed a significant reduction in expression of all microRNAs. On the other hand, only the overexpression of miR-125b caused a change in the expression pattern of MSI1 in breast epithelial cancer cell lines. Accordingly, our results demonstrated that the exogenous expression of miR-125b decreased not only the MSI1 protein but also expression of epithelial markers in breast cancer cells.ConclusionsThe results of luciferase reporter assay showed that MSI1 is a direct target for miR-125b in epithelial breast cancer cells. Moreover, higher amount of MSI1 in those cell lines seems due to the reduced amount of miR-125b, which is responsible for epithelial features of those kinds of cancer cells. Therefore, the modulation of miR-125b may be a potential approach to help to combat against epithelial breast tumors.

Antimicrobial and antibiofilm photodynamic therapy against vancomycin resistant Staphylococcus aureus (VRSA) induced infection in vitro and in vivo

Biofilm mediated infection caused by multi-drug resistant bacteria are difficult to treat since it protects the microorganisms by host defense system, making them resistant to antibiotics and other antimicrobial agents. Combating such type of nosocomial infection, especially in immunocompromised patients, is an urgent need and foremost challenge faced by clinicians. Therefore, antimicrobial photodynamic therapy (aPDT) has been intensely pursued as an alternative therapy for bacterial infections. aPDT leads to the generation of reactive oxygen species (ROS) that destroy bacterial cells in the presence of a photosensitizer, visible light and oxygen. Here, we elucidated a possibility of its clinical application by reducing the treatment time and exposing curcumin to 20 J/cm2 of blue laser light, which corresponds to only 52 s to counteract vancomycin resistant Staphylococcus aureus (VRSA) both in vitro and in vivo. To understand the mechanism of action, the generation of total reactive oxygen species (ROS) was quantified by 2′-7′-dichlorofluorescein diacetate (DCFH-DA) and the type of phototoxicity was confirmed by fluorescence spectroscopic analysis. The data showed more production of singlet oxygen, indicating type-II phototoxicity. Different anti-biofilm assays (crystal violet and congo red assays) and microscopic studies were performed at sub-MIC concentration of curcumin followed by treatment with laser light against preformed biofilm of VRSA. The result showed significant reduction in the preformed biofilm formation. Finally, its therapeutic potential was validated in skin abrasion wistar rat model. The result showed significant inhibition of bacterial growth. Furthermore, immunomodulatory analysis with rat serum was performed. A significant reduction in expression of proinflammatory cytokines TNF-α and IL-6 were observed. Hence, we conclude that curcumin mediated aPDT with 20 J/cm2 of blue laser treatment (for 52 s) could be used against multi-drug resistant bacterial infections and preformed biofilm formation as a potential therapeutic approach.

Prognostic significance of BIRC7/Livin, Bcl-2, p53, Annexin V, PD-L1, DARC, MSH2 and PMS2 in colorectal cancer treated with FOLFOX chemotherapy with or without aspirin.

Evasion of apoptosis is associated with treatment resistance and metastasis in colorectal cancer (CRC). Various cellular processes are associated with evasion of apoptosis. These include overexpression of pro-apoptotic proteins (including p53 and PD-L1), anti-apoptotic proteins (BIRC7/Livin and Bcl-2), chemokine receptors (including DARC), and dysregulation of DNA mismatch repair proteins (including MSH2 and PMS2). The aim of this study was to determine the effect of folinic acid, 5-FU and oxaliplatin (FOLFOX) as a single agent and aspirin plus FOLFOX in various combinations on the aforementioned proteins in human CRC, SW480 cell line and rat models of N-Methyl-N-Nitrosourea (NMU)-induced CRC. In addition, effects of the NMU-induced CRC and chemotherapeutic regimens on haematological and biochemical parameters in the rat models were studied. Immunohistochemistry, immunofluorescence and immunoblot techniques were used to study the expression pattern of the related proteins in the human CRC cells pre- and post-treatment. Double contrast barium enema, post-mortem examination and histological analyses were used to confirm tumour growth and the effect of the treatment in vivo in rat models. Notably, we found in human mucinous CRC, a significant increase in expression of the BIRC7/Livin post-FOLFOX treatment compared with pre-treatment (p = 0.0001). This increase provides new insights into the prognostic role of BIRC7/Livin in evasion of apoptosis and facilitation of treatment resistance, local recurrence and metastasis particularly among mucinous CRCs post-FOLFOX chemotherapy. These poor prognostic features in the CRC may be further compounded by the significant suppression of DARC, PD-L1, PMS2 and overexpression of MSH2 and anti-apoptotic Bcl-2 and p53 proteins observed in our study (p < 0.05). Importantly, we found a significant reduction in expression of BIRC7/Livin and reactivation of DARC and PD-L1 with a surge in Annexin V expression in rat models of CRC cells post-treatment with a sequential dose of aspirin plus FOLFOX compared with other treatments in vivo (p <0.05). The mechanistic rational of these effects underscores the importance of expanded concept of possible aspirin combination therapy with FOLFOX sequentially in future CRC management. Validation of our findings through randomized clinical trials of aspirin plus FOLFOX sequentially in patients with CRC is therefore warranted.

Intermittent Lipopolysaccharide Exposure Significantly Increases Cortical Infarct Size and Impairs Autophagy.

Globally, stroke is a leading cause of death and disability. Traditional risk factors like hypertension, diabetes, and obesity do not fully account for all stroke cases. Recent infection is regarded as changes in systemic immune signaling, which can increase thrombosis formation and other stroke risk factors. We have previously shown that administration of lipopolysaccharide (LPS) 30-minutes prior to stroke increases in infarct volume. In the current study, we found that animals intermittently exposed to LPS have larger cortical infarcts when compared to saline controls. To elucidate the mechanism behind this phenomenon, several avenues were investigated. We observed significant upregulation of tumor necrosis factor-alpha (TNF-α) mRNA, especially in the ipsilateral hemisphere of both saline and LPS exposed groups compared to sham surgery animals. We also observed significant reductions in expression of genes involved in autophagy in the ipsilateral hemisphere of LPS stroke animals. In addition, we assessed DNA methylation of autophagy genes and observed a significant increase in the ipsilateral hemisphere of LPS stroke animals. Intermittent exposure to LPS increases cortical infarct volume, downregulates autophagy genes, and induces hypermethylation of the corresponding CpG islands. These data suggest that intermittent immune activation may deregulate epigenetic mechanisms and promote neuropathological outcomes after stroke.

Hot-Melt Extrusion: An Emerging Technique for Solubility Enhancement of Poorly Water-Soluble Drugs.

The solubility of the drug is a significant aspect to be considered during manufacturing of pharmaceutical products. Poor aqueous solubility of drugs imparts depleted bioavailability. In this regard, several techniques are available for enhancing drug solubility or dissolution. However, only few of them are scalable and industrially applicable. Hot-melt extrusion (HME) is one such technique that has been widely used in the industry. It is a single-step, continuous manufacturing, and scalable method that has proved successful in improving the solubility of poorly soluble drugs. This review highlights the numerous pharmaceutical applications of HME, such as formulations of sterile implants, taste masking of unpleasant drugs, cocrystallization, salt formation, sustained and controlled release formulations, etc. It also describes various hydrophilic and hydrophobic carriers utilized in HME. This review also briefly discusses the recent advances in HME and gives an update on the currently available marketed products. The opportunities and challenges in future development of pharmaceutical products by HME technique are also discussed.

P38 Mitogen-activated protein kinase modulates cisplatin resistance in Head and Neck Squamous Cell Carcinoma cells

ObjectiveThis study aims to investigate the role of p38 Mitogen-activated protein kinase (MAPK) in imparting cisplatin resistance in head and neck squamous cell carcinoma (HNSCC) cells. DesignLaboratory generated cisplatin resistant HNSCC cells were treated with p38 inhibitor and were subjected to increasing dosage of cisplatin. Western blot, immunohistochemistry and RT PCR analysis were performed to investigate expression level of p-p38 and Cancer stem cell (CSC) markers in cisplatin resistant HNSCC cells with or without p38 inhibitor. Chemoresistance, wound healing capacity and Spheroids formation capacity were assessed following p38 inhibition in cisplatin resistant HNSCC cell lines. In addition, alkaline comet assay and γ-H2AX immunostaining were performed to evaluate the DNA damage response and repair abilities in cisplatin resistant HNSCC cells after p38 inhibition. ResultsIt was observed that following p38 inhibition, cisplatin resistant HNSCC cells exhibited significant reduction in expression of CSC markers, β-catenin, reduced migration potential and sphere forming ability along with increased apoptotic index demonstrating there was increased sensitivity towards Cisplatin. Molecular docking study identified several interface amino acid residues between p-p38 with CSC markers (Klf4 and CD44). p38 inhibited cisplatin resistant HNSCC cells also exhibited increased DNA damage as measured by Comet assay and γ-H2AX foci formation index. There was significant decrease in DNA repair as confirmed by reduced ERRC1 expression. ConclusionsOur study demonstrated that p38 MAPK inhibition can be a targeted approach to overcome resistance in HNSCC thereby escalating the effectiveness of chemotherapy in HNSCC.

Investigation of the response of tear-film neutrophils to interleukin 8 and their sensitivity to centrifugation, fixation, and incubation

During eye closure, a large number of neutrophils (polymorphonuclear neutrophils, PMNs) invade the ocular surface and are often referred to as tear-film PMNs. While immunophenotyping experiments have been performed on tear-film PMNs, the impact of commonly used experimental procedures on their phenotype as well as their response to interleukin-8 (IL-8), a physiological inflammatory mediator, have not yet been investigated. A gentle eye wash method was used to collect cells at home. In the morning upon awaking, participants washed their eyes with sterile phosphate buffer saline (PBS) and collected the runoff into a sterile polypropylene tube. The cell collection was then delivered to the lab within two hours. The effects of centrifugation, incubation and fixation with paraformaldehyde (PFA) before (pre-fixed staining) or after (post-fixed staining) incubation with antibodies were characterized. Tear-film PMNs as well as blood PMNs (used for comparison) were also stimulated with IL-8. To assess the reproducibility of cell collection and variability in receptor expression over time, participants were also asked to collect cells three times over a period of a month. The change in expression of surface receptors, CD11b, CD16, CD55, CD66b, important inflammatory and activation markers, and CD45 (PAN leukocyte marker) was assessed by flow cytometry. Fixing tear-film PMNs prior to the staining with antibodies resulted in a significant (fivefold or more) reduction in the expression of CD11b, CD16 and CD45 when compared to unfixed samples, while CD16 was the only receptor to undergo significant downregulation upon post-staining fixation. Furthermore, additional centrifugation step prior to antibody incubation as well as long (4 h) incubation at 37 °C resulted in significant reductions in expression of CD11b, CD16 and CD55 when compared to control samples. As opposed to blood PMNs, stimulating tear-film PMNs with IL-8 did not induce any significant changes in expression of CD11b, CD16, CD55 and CD66b. When working with collected tear-film PMNs, our results suggest that any additional centrifugation and incubation step should be avoided, or at least limited, and post fixation staining is recommended in order to preserve cell phenotype and cell integrity of tear film PMNs. Our study also adds further information on the reproducibility of the gentle eye wash as well as the inability of tear-film PMNs to modulate their surface receptors upon stimulation with IL-8. The latter may be due to prior exposure to IL-8, activation in the closed-eye environment, or a reduced ability to respond to inflammatory stimulus. Further mechanistic studies will be needed to gain a better understanding of the tear-film neutrophil phenotype.

Diesel exhaust particle exposure reduces expression of the epithelial tight junction protein Tricellulin

BackgroundWhile exposure to diesel exhaust particles has been linked to aberrant immune responses in allergic diseases such as asthma, little attention has been paid to their effects on the airway epithelial barrier. In this study, we sought to determine the effect of diesel exhaust exposure on airway epithelial barrier function and composition using in vitro and in vivo model systems.Methods16HBE14o- human bronchial epithelial cells were grown on collagen coated Transwell inserts and exposed to 5 to 50 μg/cm2 SRM 2975 diesel particulate matter (DEP) suspended in cell culture medium or vehicle controls. Changes in barrier function were assessed by measuring transepithelial electrical resistance (TEER) and permeability to 4 kDa FITC Dextran. Neonatal BALB/c mice were exposed to aerosolized DEP (255 ± 89 μg/m3; 2 h per day for 5 days) and changes in the tight junction protein Tricellulin were assessed 2 weeks post exposure.ResultsA six-hour incubation of epithelial cells with diesel exhaust particles caused a significant concentration-dependent reduction in epithelial barrier integrity as measured by decreased TEER and increased permeability to 4 kDa FITC-Dextran. This reduction in epithelial barrier integrity corresponded to a significant reduction in expression of the tight junction protein Tricellulin. siRNA mediated knockdown of Tricellulin recapitulated changes in barrier function caused by DEP exposure. Neonatal exposure to aerosolized DEP caused a significant reduction in lung Tricellulin 2 weeks post exposure at both the protein and mRNA level.ConclusionShort term exposure to DEP causes a significant reduction in epithelial barrier integrity through a reduction in the tight junction protein Tricellulin. Neonatal exposure to aerosolized DEP caused a significant and sustained reduction in Tricellulin protein and mRNA in the lung, suggesting that early life exposure to inhaled DEP may cause lasting changes in airway epithelial barrier function.

CLAUDIN7 modulates trophectoderm barrier function to maintain blastocyst development in pigs

Trophectoderm (TE) barrier function is an essential prerequisite for blastocyst development. CLAUDIN7 (CLDN7), a member of CLAUDINS family, is involved in regulating intercellular exchange and cell polarity in epithelium cells. However, the role of CLDN7 in porcine early embryo development is yet to be explored. Here, we found that CLDN7 was highly conserved in different species and was widely expressed in different tissues. Remarkably, CLDN7 expression maintained a low level from GV oocyte to 4-cell stage whereas its expression exhibited a higher level from 8-cell stage onwards. Microinjection of siRNA into cytoplasm effectively knocked down expression of CLDN7 mRNA and protein in porcine embryos. CLDN7 knockdown not only significantly reduced blastocyst rates of embryos derived from parthenogenetic activation and in vitro fertilization, but also reduced number of total cells and TE cells in the resulting blastocysts. Furthermore, CLDN7 knockdown led to a significant reduction in expression of multiple genes associated with tight junction assembly and fluid accumulation. A permeability assay revealed that CLDN7 knockdown disrupted tight junction assembly and paracellular sealing in the TE epithelium. Taken together, these results demonstrate that CLDN7 regulates porcine blastocyst development via modulating trophectoderm barrier function.

Memantine ameliorates tau protein deposition and secondary damage in the ipsilateral thalamus and sensory decline following focal cortical infarction in rats

Previous studies have reported that memantine presents evidence of therapeutic benefits in several animal models of ischemic stroke and neurodegenerative diseases. However, the effect of memantine on secondary damage in the ipsilateral thalamus after focal cortical infarction remains undefined. Present study investigated whether memantine has a protective effect on secondary damage in the ipsilateral thalamus after focal cerebral infarction in rats. At 24 h after distal middle cerebral artery occlusion (MCAO), rats in the memantine and vehicle groups were intraperitoneal injected with memantine and isopycnic vehicle, respectively, was once daily administered for consecutive 7 days. Infarct size was evaluated through Nissl staining and sensory decline determined using adhesive removal test. Secondary thalamic damage was assessed using Nissl staining and immunofluorescence 8 days after MCAO. Immunoboltting was used to identify tau and apoptosis-associated proteins in the ipsilateral thalamus after MCAO. Results revealed that memantine ameliorated sensory decline compared to the vehicle controls. Subsequently, tau phosphorylated at threonine 231 (p-tau-231), glycogen synthase kinase3βpY216 (GSK3βpY216) and protein phosphatase 2A (PP2ApY307) were reduced by memantine, causing greater reduction in neuronal loss and inhibition of reactive astrogliosis in the ipsilateral ventroposterior thalamic nucleus (VPN) compared with the vehicle groups. In addition, increase in secondary damage-induced TUNEL-positive cells was blunted by memantine, as demonstrated by the significant reduction in expression of apoptosis-associated proteins. Our results suggest that memantine has a neuro-protective effect on secondary damage in the ipsilateral thalamus following MCAO by inhibiting the activity of GSK3βpY216/PP2ApY307 and down regulating the levels of p-tau-231 protein.

Paradoxical Effect of TNFα on Mitochondrial Function and Metabolic Activity in the Retinal Pigment Epithelium (RPE)

The retinal pigment epithelium (RPE) acts as a metabolic gatekeeper between photoreceptors and the choroidal vasculature to maintain healthy retinal function. RPE dysfunction is a key feature of age‐related macular degeneration (AMD), the leading cause of blindness in developed countries. Tumor necrosis factor‐alpha (TNFα), a potent pro‐inflammatory cytokine, has been implicated in the pathogenesis of AMD. Growing evidence supports metabolic dysfunction as another key mechanism driving AMD. To date, there is no literature on the metabolic effects of TNFα on RPE and thus, this study sheds light on the impact of TNFα on mitochondrial morphology and metabolic function in RPE. Matured ARPE‐19 (human RPE cell line) were treated with TNFα (10 ng/ml) for up to 72h. TNFα induced ARPE‐19 to elongate into spindle‐shaped cells, reminiscent of epithelial‐mesenchymal transition (EMT). However, qPCR showed that TNFα reduced the expression of EMT genes (α‐SMA, Col1A1, fibronectin, MMP2, CTGF) indicating that the elongated cells were not mesenchymal in nature. To explore the effects of TNFα on metabolism, two major energy‐generating pathways, oxidative phosphorylation (OXPHOS) and glycolysis were assessed by Seahorse high‐resolution respirometry and qPCR. The Seahorse Mito Stress Test revealed an increase in basal respiration but reduced spare respiratory capacity following TNFα treatment. TNFα increased glycolytic reserve and capacity. Despite the increased OXPHOS and glycolysis, qPCR showed a significant reduction in expression of OXPHOS (ATP5O, COX4I1, COX5B, NDUFB5) and glycolysis (G6P, PFKL, PFKFB3, PGK1, LDHA) genes with TNFα treatment. ARPE‐19 were transfected with mitochondria‐tagged GFP and imaged using confocal microscopy. Parameters on mitochondrial morphology were extracted from the confocal images using automated image segmentation and revealed that TNFα disrupted mitochondrial network integrity. This was supported by qPCR data showing significantly reduced expression of genes regulating mitochondrial function (PGC‐1α, TFAM, POLG, MFN1, MFN2, FIS1, OPA1). TNFα significantly elevated SOD2, a mitochondrial antioxidant enzyme, but not SOD1. Taken together, we find that TNFα robustly disrupts mitochondrial function and morphology in RPE, although shifting the bioenergetic profile in a paradoxical manner, i.e. TNFα raised the levels of basal respiration and glycolysis despite the suppression of genes regulating OXPHOS and glycolysis. These findings highlight the potential of targeting metabolic pathways in RPE as a promising therapeutic avenue for AMD. Further research is required to elucidate the mechanisms underlying these intriguing TNFα‐driven metabolic changes.Support or Funding InformationGrimshaw‐Gudewicz Charitable Foundation; National Council of Scientific and Technological Development—Brazil (PDE 210474/2014‐9); The Iraty Award; NEI Core Grant P30EYE003790; Department of Defense, Spinal Vision Research Program under Award no. VR180132

Abstract P2-20-04: Controlling tight junctions in the blood brain barrier (BBB) with artemisinin as a potential adjuvant in the treatment of metastatic disease

Abstract Introduction: Brain metastatic disease (BMD) is attributed to significant mortality and morbidity in breast cancer patients. Strict policing of molecular traffic across the blood-brain barrier (BBB) precludes brain parenchymal penetration of most small molecule drugs, chemotherapy included. Consequently, the treatment of BMD remains difficult, particularly if the BBB remains intact during disease progression. Artemisinin has been efficacious in treating multi-drug resistant cerebral malaria likely indicative of an ability to traverse the BBB. Thus, Artemisinin may be able to modulate the restrictive nature of the BBB and provide a potential adjunctive therapy to established drug therapy in the treatment of BMD. Emerging evidence suggests that Artemisinin itself may harbour potent anti-cancer properties. Aim: To investigate in vitro the effect on barrier function in particular paracellular permeability of brain vascular endothelial cells compared to non-brain vascular endothelial cells when treated with Artemisinin. Materials and Methods: Inter-individual BBB differences were modelled using the human brain vascular endothelial cell lines hCMEC-D3, TY09 and TY10. In addition to the brain cell lines, a HUVEC cell line was treated with incremental concentrations of artemisinin. Adhesion, migration and electrical resistance across cellular monolayers were quantified using Electric Cell-Substrate Impedance Sensing (ECIS). Trans- Endo/Epithelial Resistance (TEER) and Paracellular Permeability (PCP) were used to assess barrier function. Immunofluorescence was used to qualitatively assess tight junction (TJ) integrity of all cell lines. RNAseq was used to determine changes in message after treatment with Artemisinin in all 4 cell lines. Results: A significant reduction in electrical resistance across all cell lines was observed when treated with 1mM Artemisinin and may be suggestive of a cytotoxic concentration. In comparison when treated with 0.01mM Artemisinin the electrical resistance decreased which could suggest restrictive barrier properties were enhanced, in addition evidencing Artemisinin may exhibit biphasic activity. The reduction in electrical resistance across the brain endothelial cell lines was significant (p&amp;lt;0.05) but deemed not significant across HUVEC, perhaps mirroring Artemisinin’s pharmacological action at differing vascular interfaces in vivo. Higher Artemisinin concentrations significantly reduced TEER across the brain cell lines and increased paracellular permeability, the same trends were observed in HUVEC. IF demonstrated that Artemisinin was able to effect changes in TJ protein location which supports the hypothesis that Artemisinin reduces barrier function across the brain endothelial lines, suggested by an increased permeability in the presence of Artemisinin. Electrical resistance across all cell lines significantly reduced when treated with 1mM Artemisinin. When compared to negative control, there was a significant decrease in electrical resistance across all cell lines treated with 1mM Artemisinin. RNAseq comparisons revealed that in TY10 cells, 1167 genes were upregulated and 94 downregulated in comparison to HUVEC where 185 and 0 genes were up or downregulated respectively and that in all 3 brain endothelial cell lines that the TJ protein CLDN5 exhibited a significant reduction in expression at gene level (p=0.03). Conclusion: The results demonstrate that Artemisinin may have the capacity to transiently increase or decrease the permeability of the BBB. Therefore, Artemisinin may have a role in facilitating drug delivery to the cerebral parenchyma providing potential therapeutic benefit for the treatment of BMD or other related neurological conditions difficult to treat due to the BBB. Citation Format: Emily Appadurai, Fiona Ruge, Andrew Sanders, Wen G Jiang, Tracey A. Martin. Controlling tight junctions in the blood brain barrier (BBB) with artemisinin as a potential adjuvant in the treatment of metastatic disease [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-20-04.

Allyl isothiocyanate treatment alleviates chronic obstructive pulmonary disease through the Nrf2-Notch1 signaling and upregulation of MRP1

AimsChronic obstructive pulmonary disease (COPD) is a disease with high morbidity and mortality worldwide, which can cause serious social and economic burdens. Allyl isothiocyanate (AITC) is one of the most common natural isothiocyanates and has been shown to have anti-inflammatory and antioxidant biological activities. The purpose of this study was to investigate whether AITC regulated Multidrug resistance-associated protein 1 (MRP1), reactive oxide species (ROS) and reduced glutathione (GSH) levels via Nrf2 and Notch1 signaling pathways to treat COPD and whether there was an interaction between these two pathways. Main methodsLung function indexes and histopathological changes in mice were determined by lung function instrument and HE staining, respectively. The protein expression was analyzed using immunohistochemistry and Western blotting. The mRNA expression was measured by RT-PCR in human bronchial epithelial cell line 16HBE. The contents of ROS, GSH and GSSG were detected by kits in 16HBE cells. Key findingsThe protein expression of Notch1, Hes1, MRP1, Nrf2, and HO-1 in lung tissues of WT mice and untransfected cells were significantly down-regulated in COPD, then significantly ameliorated in treatment groups. The protein expression of MRP1, Notch1 and Hes1 in lung tissues of Nrf2−/− mice were markedly reduced. There was a significant reduction in expression of Nrf2, HO-1 and MRP1 in si-Notch1 transfected cells. Pretreatment with AITC markedly improved oxidative stress and GSH-redox disorder in COPD. SignificanceOur study demonstrates that there is a potential interaction between Nrf2 and Notch1 signaling pathways during treatment of COPD.

Deficiency of immunoglobulin E protects mice from experimental abdominal aortic aneurysms.

Allergic asthma with high plasma IgE levels is a significant risk factor of human abdominal aortic aneurysm (AAA). This study tests a direct role of IgE in angiotensin-II (Ang-II) perfusion- and peri-aortic CaCl2 injury-induced AAA in mice. In both models, IgE-deficiency in Apoe-/- Ige-/- mice blunts AAA growth and reduces lesion accumulation of macrophages, CD4+ and CD8+ T cells, and lesion MHC class-II expression, CD31+ microvessel growth, and media smooth muscle cell loss, compared with those from Apoe-/- control mice. Real time-PCR reveals significant reductions in expression of neutrophil chemoattractants MIP-2α and CXCL5 in AAA lesions or macrophages from Apoe-/- Ige-/- mice, along with reduced lesion Ly6G+ neutrophil accumulation. Consistent with reduced lesion inflammatory cell accumulation, we find significant reductions of plasma and AAA lesion IL6 expression in Apoe-/- Ige-/- mice. Immunofluorescent staining and FACS analysis show that AAA lesion neutrophils express FcεR1. Mechanistic study demonstrates that IgE induces neutrophil FcεR1 expression, activates MAPK signaling, and promotes IL6 production. This study supports a direct role of IgE in AAA by promoting lesion chemokine expression, inflammatory cell accumulation, MAPK signaling, and cytokine expression. IgE inhibition may represent a novel therapeutic approach in AAA management.

Endothelial intercellular cell adhesion molecule 1 contributes to cell aggregate formation in CHO cells cultured in serum-free media.

Chinese hamster ovary (CHO) cells have been adapted to grow in serum-free media and in suspension culture to facilitate manufacturing needs. Some CHO cell lines, however, tend to form cell aggregates while being cultured in suspension. This can result in reduced viability and capacity for single cell cloning (SCC) via limiting dilution, and process steps to mitigate cell aggregate formation, for example, addition of anti-cell-aggregation agents. In this study, we have identified endothelial intercellular cell adhesion molecule 1 (ICAM-1) as a key protein promoting cell aggregate formation in a production competent CHO cell line, which is prone to cell aggregate formation. Knocking out (KO) the ICAM-1 gene significantly decreased cell aggregate formation in the culture media without anti-cell-aggregation reagent. This trait can simplify the process of transfection, selection, automated clone isolation, and so on. Evaluation in standard cell line development of ICAM-1 KO and wild-type CHO hosts did not reveal any noticeable impacts on titer or product quality. Furthermore, analysis of a derived nonaggregating cell line showed significant reductions in expression of cell adhesion proteins. Overall, our data suggest that deletion of ICAM-1 and perhaps other cell adhesion proteins can reduce cell aggregate formation and improve clonality assurance during SCC.

P-Coumaric Acid Mitigates Doxorubicin-Induced Nephrotoxicity Through Suppression of Oxidative Stress, Inflammation and Apoptosis

P-Coumaric acid (PCA) is one the compound that has free radical scavenging effects. This study investigates the protective effect of PCA on tissue damage in DOX-induced nephrotoxicity. Thirty two Wistar rats were divided into control, PCA, DOX (15mg/kg, i.p.) and DOX plus PCA (100mg/kg, orally) groups. DOX-induced nephrotoxicity was indicated by marked increase in blood urea nitrogen (BUN) and serum creatinine (Cr) compared to controls. DOX group also showed elevations in lipid peroxidation and reductions in enzyme activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT). Expression of renal inflammatory cytokines including tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) and apoptosis were also elevated in the DOX group. PCA significantly reversed, nephrotoxicity induced by DOX via lowering BUN, serum Cr and improving histopathological scores as compared to the DOX group. PCA also decreased lipid peroxidation, increased activities of GPx, SOD and CAT, to levels relatively comparable to control. Significant reductions in expression of TNF-α, IL-1β and apoptosis were also observed following Co-administration of PCA relative to the DOX group. Results describe a protective effect of PCA against DOX-induced nephrotoxicity. This effect is likely facilitated through inhibition of oxidative stress, inflammation and apoptosis.

Angiotensin II down-regulates transferrin receptor 1 and ferroportin 1 expression in Neuro-2a cells via activation of type-1 receptor

Angiotensin II (ANGII) modulates expression of iron intake and export proteins in cultured neurons. However, the relevant mechanisms have not been fully elucidated. Here, we investigated the effects of ANGII and/or candesartan, a ANGII-Type-1 Receptor (AT1R) antagonist, and PD123319, a ANGII-Type-2 Receptor (AT2R) antagonist on expression of transferrin receptor 1 (TfR1), ferroportin 1 (Fpn1)and ferritin as well as iron regulatory proteins (IRPs), hepcidin and nuclear factor E2-related factor 2 (Nrf2) in Neuro-2a cells. We demonstrated that ANGII induces a significant reduction in expression of TfR1, Fpn1, IRP2 proteins and Nrf2 mRNA and an increase in ferritin protein and hepcidin mRNA, while candesartan, but not PD123319, significantly attenuated or reversed all these ANGII-induced changes in Neuro-2a cells. These findings imply that ANGII down-regulates TfR1 expression likely via the AT1R/IRP2 pathway, and Fpn1 expression via ATR1/hepcidin and AT1R/ Nrf2 pathways.

In vitro activity of aryl-thiazole derivatives against Schistosoma mansoni schistosomula and adult worms.

Schistosomiasis is caused by a trematode of the genus Schistosoma and affects over 200 million people worldwide. The only drug recommended by the World Health Organization for treatment and control of schistosomiasis is praziquantel. Development of new drugs is therefore of great importance. Thiazoles are regarded as privileged structures with a broad spectrum of activities and are potential sources of new drug prototypes, since they can act through interactions with DNA and inhibition of DNA synthesis. In this context, we report the synthesis of a series of thiazole derivatives and their in vitro schistosomicidal activity by testing eight molecules (NJ03-08; NJ11-12) containing thiazole structures. Parameters such as motility and mortality, egg laying, pairing and parasite viability by ATP quantification, which were influenced by these compounds, were evaluated during the assays. Scanning electron microscopy (SEM) was utilized for evaluation of morphological changes in the tegument. Schistosomula and adult worms were treated in vitro with different concentrations (6.25 to 50 μM) of the thiazoles for up to 5 and 3 days, respectively. After in vitro treatment for five days with 6.25 μM NJ05 or NJ07 separately, we observed a decrease of 30% in schistosomula viability, whilst treatment with NJ05+NJ07 lead to a reduction of 75% in viability measured by ATP quantitation and propidium iodide labeling. Adult worms' treatment with 50 μM NJ05, NJ07 or NJ05 + NJ07 showed decreased motility to 30-50% compared with controls. Compound NJ05 was more effective than NJ07, and adult worm viability after three days was reduced to 25% in parasites treated with 50 μM NJ05, compared with a viability reduction to 40% with 50 μM NJ07. SEM analysis showed severe alterations in adult worms with formation of bulges and blisters throughout the dorsal region of parasites treated with NJ05 or NJ07. Oviposition was extremely affected by treatment with the NJ series compounds; at concentrations of 25 μM and 50 μM, oviposition reached almost zero with NJ05, NJ07 or NJ05 + NJ07 already at day one. Tested genes involved in egg biosynthesis were all confirmed by qPCR as downregulated in females treated with 25 μM NJ05 for 2 days, with a significant reduction in expression of p14, Tyrosinase 2, p48 and fs800. NJ05, NJ07 or NJ05+NJ07 treatment of HEK293 (human embryonic cell line) and HES (human epithelial cell line) showed EC50 in the range of 18.42 to 145.20 μM. Overall, our results demonstrate that those molecules are suitable targets for further development into new drugs for schistosomiasis treatment, although progress is needed to lessen the cytotoxic effects on human cells. According to the present study, thiazole derivatives have schistosomicidal activities and may be part of a possible new arsenal of compounds against schistosomiasis.