Tubulin Staining Research Articles

Anticancer Effect of PtIIPHENSS, PtII5MESS, PtII56MESS and Their Platinum(IV)-Dihydroxy Derivatives against Triple-Negative Breast Cancer and Cisplatin-Resistant Colorectal Cancer.

Development of resistance to cisplatin, oxaliplatin and carboplatin remains a challenge for their use as chemotherapies, particularly in breast and colorectal cancer. Here, we compare the anticancer effect of novel complexes [Pt(1,10-phenanthroline)(1S,2S-diaminocyclohexane)](NO3)2 (PtIIPHENSS), [Pt(5-methyl-1,10-phenanthroline)(1S,2S-diaminocyclohexane)](NO3)2 (PtII5MESS) and [Pt(5,6-dimethyl-1,10-phenanthroline)(1S,2S-diaminocyclohexane)](NO3)2 (PtII56MESS) and their platinum(IV)-dihydroxy derivatives with cisplatin. Complexes are greater than 11-fold more potent than cisplatin in both 2D and 3D cell line cultures with increased selectivity for cancer cells over genetically stable cells. ICP-MS studies showed cellular uptake occurred through an active transport mechanism with considerably altered platinum concentrations found in the cytoskeleton across all complexes after 24 h. Significant reactive oxygen species generation was observed, with reduced mitochondrial membrane potential at 72 h of treatment. Late apoptosis/necrosis was shown by Annexin V-FITC/PI flow cytometry assay, accompanied by increased sub-G0/G1 cells compared with untreated cells. An increase in S and G2+M cells was seen with all complexes. Treatment resulted in significant changes in actin and tubulin staining. Intrinsic and extrinsic apoptosis markers, MAPK/ERK and PI3K/AKT activation markers, together with autophagy markers showed significant activation of these pathways by Western blot. The proteomic profile investigated post-72 h of treatment identified 1597 MDA-MB-231 and 1859 HT29 proteins quantified by mass spectroscopy, with several differentially expressed proteins relative to no treatment. GO enrichment analysis revealed a statistically significant enrichment of RNA/DNA-associated proteins in both the cell lines and specific additional processes for individual drugs. This study shows that these novel agents function as multi-mechanistic chemotherapeutics, offering promising anticancer potential, and thereby supporting further research into their application as cancer therapeutics.

An improved method for tubulin staining of ciliated eukaryotes

Ciliated microeukaryotes (ciliates) are distinguished by their cilia, which are rich in tubulin. We developed a method for tubulin staining in ciliate cells that involves using live-cell tubulin-staining dyes instead of antibodies thereby streamlining the staining process, which is effective across diverse ciliate lineages. Moreover, our method allows integration with immunofluorescence staining using antibodies when needed. The potential applications of this technique extend to cell biology and ciliate morphological and ecological studies.

MP65-20 SMALL MOLECULE-DIRECTED BLADDER TISSUE REGENERATION

You have accessJournal of UrologyCME1 Apr 2023MP65-20 SMALL MOLECULE-DIRECTED BLADDER TISSUE REGENERATION Mitali Kini, Matthew Bury, Natalie Fuller, Larry Wang, Tiffany Sharma, and Arun Sharma Mitali KiniMitali Kini More articles by this author , Matthew BuryMatthew Bury More articles by this author , Natalie FullerNatalie Fuller More articles by this author , Larry WangLarry Wang More articles by this author , Tiffany SharmaTiffany Sharma More articles by this author , and Arun SharmaArun Sharma More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003323.20AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Co-seeded mesenchymal stem cell (MSC)/CD34+ hematopoietic stem cell (HSC) citrate based scaffolds (CBS) have been successfully utilized to regenerate bladder tissue. However, the acquisition and downstream utility of these cells remains an obstacle. Here, we compare the bladder tissue regenerative capacity of the small molecule PRKR against MSC/HSC seeded CBS in a rat bladder augmentation model. METHODS: Nude rats underwent an∼75% bladder cystectomy then augmented with a CBS and then 1) instilled with saline (SAL, n=7); 2) instilled with PRKR 1x/week for 2 weeks (n=7); or 3) seeded with human MSC/CD34+ HSCs (CS, n=4). Animals were sacrificed 10 weeks post-augmentation. Quantitative morphometrics was used to assess regenerated tissue with regards to muscle content, urothelium width, and vascularization via histology. Peripheral nerve regeneration was assessed by βIII tubulin staining. Urodynamic studies (UDS) and capacity measures were performed pre- and 10 weeks post-augmentation. RESULTS: SAL instilled animals demonstrated 24.50±2.27% muscle content while PRKR and CS instilled animals were 47.00±1.81% and 50.72±1.67% muscle content, respectively. PRKR vs SAL was p<0.0001 and CS vs SAL was p<0.0001. Urothelium width (µm) measurements demonstrated that SAL maintained a 40.82±2.15µm width where PRKR and CS constructs were 52.98±2.55 µm and 59.38±5.07µm in width, respectively. PRKR vs SAL p<0.05; CS vs SAL p<0.01. There was no statistical significance between PRKR and CS groups. Furthermore, SAL instilled animals demonstrated 1.49±0.13% vascularization while PRKR instilled and CS animals were 3.60±0.24% and 4.76±0.34% vascularization, respectively. PRKR vs SAL and CS vs SAL was p<0.0001 and PRKR vs CS groups was p<0.05. With regards to UDS, SAL instilled animals demonstrated an approximate return to pre-augmentation intravesical pressure (40cm H2O) at 10 weeks post-augmentation. PRKR instilled animals showed a decrease in pressure reaching ∼25cm H2O. Similarly, CS animals returned to pre-augmentation values. Regarding percent bladder recovery, PRKR vs SAL was p<0.0001 (206.93±11.93% vs 80.28±5.61%) and CS vs SAL was p<0.0001 (111.13±2.67% vs 80.28±5.61%). There was a statistical significance between PRKR and CS groups, p<0.0001. In all studies, p<0.05 was considered statistically significant and data represents means±SE. βIII tubulin staining was evident in PRKR and CS groups but diminished in SAL groups. CONCLUSIONS: Data demonstrate that PRKR can be used in lieu of CS scaffolds and may also provide an alternative to bladder augmentation enterocystoplasty. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e899 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Mitali Kini More articles by this author Matthew Bury More articles by this author Natalie Fuller More articles by this author Larry Wang More articles by this author Tiffany Sharma More articles by this author Arun Sharma More articles by this author Expand All Advertisement PDF downloadLoading ...

Corneal wound healing and nerve regeneration by novel ophthalmic formulations based on cross-linked sodium hyaluronate, taurine, vitamin B6, and vitamin B12.

Introduction: To evaluate the pharmacological profile of ocular formulations based on cross-linked sodium hyaluronate (CL-SH), taurine (Tau), vitamin B6 (Vit B6) and vitamin B12 (Vit B12) using in vitro and in vivo paradigms. Methods: Rabbit corneal epithelial cells were used to assess wound healing and reactive oxygen species (ROS) formation by scratch assay and oxidative stress (0.3mM H2O2; 30min), respectively with or without ocular formulations exposure. In vivo studies were carried out on albino rabbits to evaluate corneal nerve regeneration and corneal wound healing with or without treatment with six different formulations. Animals were anesthetized, the corneal epithelium was removed, and formulations were topically administered (30μL/eye; 3 times/day for 6days). Slit-lamp observation was carried out at different time points. After 6days the animals were killed, and corneas were collected to evaluate corneal re-innervation by immunohistochemistry of selective neuronal marker β-III tubulin. Results: Formulations containing the concentrations 0.16% or 0.32% of cross-linked sodium hyaluronate, taurine, vitamin B6 and vitamin B12 accelerated corneal wound healing. Cells exposed to H2O2 led to significant (p < 0.05) increase of reactive oxygen species concentration that was significantly (p < 0.05) counteract by formulations containing cross-linked sodium hyaluronate (0.32%) and taurine with or without vitamins. The extent of re-innervation, in terms of β-III tubulin staining, was 5-fold greater (p < 0.01) in the eye of rabbits treated with formulation containing 0.32% cross-linked sodium hyaluronate, taurine, vitamins (RenerviX®) compared with the control group (no treatment). Furthermore, re-innervation elicited by RenerviX® was significantly greater (p < 0.01) compared with the group treated with the formulation containing 0.32% cross-linked sodium hyaluronate and taurine without vitamins, and with the group treated with the formulation containing 0.5% linear sodium hyaluronate (SH), taurine, and vitamin B12, respectively. Discussion: In conclusion, among the formulations tested, the new ophthalmic gel RenerviX® was able to contrast oxidative stress, to accelerate corneal re-epithelization and to promote nerve regeneration.

Nerve regeneration and corneal wound healing by ophthalmic formulations based on sodium hyaluronate, taurine, vitamin B6 and vitamin B12

AbstractPurpose: To evaluate the pharmacological profile of ocular formulations based on cross‐linked sodium hyaluronate (CL‐SH), taurine (Tau), Vit B6 and Vit B12 using in vitro and in vivo paradigms.Methods: Rabbit corneal epithelial cells (SIRC) were used to assess wound healing and ROS formation by scratch assay and oxidative stress (0.3 mM H2O2; 30 min), respectively w/ or w/o ocular formulations exposure. In vivo studies were carried out on albino rabbits to evaluate corneal nerve regeneration and corneal wound healing with or without treatment with six different formulations. Animals were anaesthetised, the corneal epithelium was removed, and formulations were topically administered (30 μl/eye; 3 times/day for 6 days). Slit‐lamp observation was carried out at the following day: T0, T2 and T5. After 6 days the animals were killed, and corneas were collected to evaluate corneal re‐innervation by immunohistochemistry of selective neuronal marker β‐III tubulin.Results: Formulations containing the concentrations 0.16% or 0.32% of CL‐SH, Tau, Vit B6 and B12 accelerated corneal wound healing. Cells exposed to H2O2 led to significant (p &lt; 0.001) increase of ROS concentration that was significantly (p &lt; 0.001) counteract by formulations containing CL‐SH (0.32%) and Tau w/ or w/o Vit B6 and B12. The extent of re‐innervation, in terms of β‐III tubulin staining, was 5‐fold greater (p &lt; 0.01) in the eye of rabbits treated with formulation containing 0.32% CL‐SH, Tau, Vit B6 and Vit B12 (RenerviX®) compared with the control group (no treatment). Furthermore, re‐innervation with RenerviX® group was significantly greater (p &lt; 0.01) also compared with the groups treated with the formulation containing 0.32% CL‐SH and Tau w/o vitamins and with the formulation containing 0.5% linear SH, Tau, and Vit B12.Conclusions: Among all formulations tested, the new ophthalmic gel RenerviX® was able to contrast oxidative stress, to accelerate corneal re‐epithelization and to promote nerve regeneration.

Distinct Mechanisms of Cytotoxicity in Novel Nitrogenous Heterocycles: Future Directions for a New Anti-Cancer Agent.

Electron-rich, nitrogenous heteroaromatic compounds interact more with biological/cellular components than their non-nitrogenous counterparts. The strong intermolecular interactions with proteins, enzymes, and receptors confer significant biological and therapeutic properties to the imidazole derivatives, giving rise to a well-known and extensively used range of therapeutic drugs used for infections, inflammation, and cancer, to name a few. The current study investigates the anti-cancer properties of fourteen previously synthesized nitrogenous heterocycles, derivatives of imidazole and oxazolone, on a panel of cancer cell lines and, in addition, predicts the molecular interactions, pharmacokinetic and safety profiles of these compounds. Method: The MTT and CellTiter-Glo® assays were used to screen the imidazole and oxazolone derivatives on six cancer cell lines: HL60, MDA-MB-321, KAIMRC1, KMIRC2, MCF-10A, and HCT8. Subsequently, in vitro tubulin staining and imaging were performed, and the level of apoptosis was measured using the Promega ApoTox-Glo® triplex assay. Furthermore, several computational tools were utilized to investigate the pharmacokinetics and safety profile, including PASS Online, SEA Search, the QikProp tool, SwissADME, ProTox-II, and an in silico molecular docking study on tubulin to identify the critical molecular interactions. Results: In vitro analysis identified compounds 8 and 9 to possess the most significant potent cytotoxic activity on the HL60 and MDA-MB-231 cell lines, supported by PASS Online anti-cancer predictions with pa scores of 0.413 and 0.434, respectively. In addition, compound 9 induced caspase 3/7 dependent-apoptosis and interfered with tubulin polymerization in the MDA-MB-231 cell line, consistent with in silico docking results, identifying binding similarity to the native ligand colchicine. All the derivatives, including compounds 8 and 9, had acceptable pharmacokinetics; however, the safety profile was suboptimal for all the tested derivates except compound 4. Conclusion: The imidazole derivative compound 9 is a promising anti-cancer agent that switches on caspase-dependent apoptotic cell death and modulates microtubule function. Therefore, it could be a lead compound for further drug optimization and development.

Acute and Delayed Effects of Mechanical Injury on Calcium Homeostasis and Mitochondrial Potential of Primary Neuroglial Cell Culture: Potential Causal Contributions to Post-Traumatic Syndrome.

In vitro models of traumatic brain injury (TBI) help to elucidate the pathological mechanisms responsible for cell dysfunction and death. To simulate in vitro the mechanical brain trauma, primary neuroglial cultures were scratched during different periods of network formation. Fluorescence microscopy was used to measure changes in intracellular free Ca2+ concentration ([Ca2+]i) and mitochondrial potential (ΔΨm) a few minutes later and on days 3 and 7 after scratching. An increase in [Ca2+]i and a decrease in ΔΨm were observed ~10 s after the injury in cells located no further than 150–200 µm from the scratch border. Ca2+ entry into cells during mechanical damage of the primary neuroglial culture occurred predominantly through the NMDA-type glutamate ionotropic channels. MK801, an inhibitor of this type of glutamate receptor, prevented an acute increase in [Ca2+]i in 99% of neurons. Pathological changes in calcium homeostasis persisted in the primary neuroglial culture for one week after injury. Active cell migration in the scratch area occurred on day 11 after neurotrauma and was accompanied by a decrease in the ratio of live to dead cells in the areas adjacent to the injury. Immunohistochemical staining of glial fibrillary acidic protein and β-III tubulin showed that neuronal cells migrated to the injured area earlier than glial cells, but their repair potential was insufficient for survival. Mitochondrial Ca2+ overload and a drop in ΔΨm may cause delayed neuronal death and thus play a key role in the development of the post-traumatic syndrome. Preventing prolonged ΔΨm depolarization may be a promising therapeutic approach to improve neuronal survival after traumatic brain injury.

Simvastatin Downregulates Cofilin and Stathmin to Inhibit Skeletal Muscle Cells Migration.

Statins are the most effective therapeutic agents for reducing cholesterol synthesis. Given their widespread use, many adverse effects from statins have been reported; of these, musculoskeletal complications occurred in 15% of patients after receiving statins for 6 months, and simvastatin was the most commonly administered statin among these cases. This study investigated the negative effects of simvastatin on skeletal muscle cells. We performed RNA sequencing analysis to determine gene expression in simvastatin-treated cells. Cell proliferation and migration were examined through cell cycle analysis and the transwell filter migration assay, respectively. Cytoskeleton rearrangement was examined through F-actin and tubulin staining. Western blot analysis was performed to determine the expression of cell cycle-regulated and cytoskeleton-related proteins. Transfection of small interfering RNAs (siRNAs) was performed to validate the role of cofilin and stathmin in the simvastatin-mediated inhibition of cell migration. The results revealed that simvastatin inhibited the proliferation and migration of skeletal muscle cells and affected the rearrangement of F-actin and tubulin. Simvastatin reduced the expression of cofilin and stathmin. The knockdown of both cofilin and stathmin by specific siRNA synergistically impaired cell migration. In conclusion, our results indicated that simvastatin inhibited skeletal muscle cell migration by reducing the expressions of cofilin and stathmin.

Tgfbr2 in Dental Pulp Cells Guides Neurite Outgrowth in Developing Teeth.

Transforming growth factor β (TGFβ) plays an important role in tooth morphogenesis and mineralization. During postnatal development, the dental pulp (DP) mesenchyme secretes neurotrophic factors that guide trigeminal nerve fibers into and throughout the DP. This process is tightly linked with dentin formation and mineralization. Our laboratory established a mouse model in which Tgfbr2 was conditionally deleted in DP mesenchyme using an Osterix promoter-driven Cre recombinase (Tgfbr2 cko ). These mice survived postnatally with significant defects in bones and teeth, including reduced mineralization and short roots. Hematoxylin and eosin staining revealed reduced axon-like structures in the mutant mice. Reporter imaging demonstrated that Osterix-Cre activity within the tooth was active in the DP and derivatives, but not in neuronal afferents. Immunofluorescence staining for β3 tubulin (neuronal marker) was performed on serial cryosections from control and mutant molars on postnatal days 7 and 24 (P7, P24). Confocal imaging and pixel quantification demonstrated reduced innervation in Tgfbr2 cko first molars at both stages compared to controls, indicating that signals necessary to promote neurite outgrowth were disrupted by Tgfbr2 deletion. We performed mRNA-Sequence (RNA-Seq) and gene onotology analyses using RNA from the DP of P7 control and mutant mice to investigate the pathways involved in Tgfbr2-mediated tooth development. These analyses identified downregulation of several mineralization-related and neuronal genes in the Tgfbr2 cko DP compared to controls. Select gene expression patterns were confirmed by quantitative real-time PCR and immunofluorescence imaging. Lastly, trigeminal neurons were co-cultured atop Transwell filters overlying primary Tgfbr2 f/f DP cells. Tgfbr2 in the DP was deleted via Adenovirus-expressed Cre recombinase. Confocal imaging of axons through the filter pores showed increased axonal sprouting from neurons cultured with Tgfbr2-positive DP cells compared to neurons cultured alone. Axon sprouting was reduced when Tgfbr2 was knocked down in the DP cells. Immunofluorescence of dentin sialophosphoprotein in co-cultured DP cells confirmed reduced mineralization potential in cells with Tgfbr2 deletion. Both our proteomics and RNA-Seq analyses indicate that axonal guidance cues, particularly semaphorin signaling, were disrupted by Tgfbr2 deletion. Thus, Tgfbr2 in the DP mesenchyme appears to regulate differentiation and the cells’ ability to guide neurite outgrowth during tooth mineralization and innervation.

Maternal deprivation induces cytoskeletal alterations and depressive-like behavior in adult male rats by regulating the AKT/GSK3β/CRMP2 signaling pathway

Early-life adverse events exert persistent effects on brain functions and may increase the risk of psychopathology in adulthood. However, the underlying mechanism remains unclear. The purpose of our study was to study the long-lasting effects of maternal deprivation (MD) on depression-related behaviors and microtubule dynamics, and to illuminate the underlying molecular mechanism. Rat pups were separated from the dams for 360 min (MD) or 15 min (brief maternal separation) each day from postnatal day 4 through 10. Rats with MD experience showed significant depressive-like behaviors in adulthood, while brief maternal separation did not alter the behaviors. Behavioral alterations in the MD group were accompanied by alterations in the AKT/GSK3β/CRMP2 signaling pathway and hyperphosphorylation of CRMP2. CRMP2 interacted and colocalized with the cytoskeleton in the hippocampus, and the overlap of CRMP2 and tubulin staining in the hippocampus of MD rats was decreased. In MD rats, the expression of the α-tubulin isoforms Acet-tubulin and Tyr-tubulin changed, and the ratio of Tyr/Acet-tubulin, which is an important marker of microtubule dynamics, was decreased, indicating decreased microtubule dynamics. Furthermore, regulation of the AKT/GSK3β/CRMP2 signaling pathway by an LY294002 microinjection in the hippocampus resulted in cytoskeletal alterations and depressive-like behaviors in rats. These findings suggest that early-life MD induces depressive-like behaviors and cytoskeletal alterations in adult male rats and that the effects may be partly mediated by the AKT/GSK3β/CRMP2 signaling pathway. An understanding of the mechanism underlying the effect of MD on behaviors is crucial for developing pharmacological and psychological interventions for childhood neglect.

Neuroprotective role of epigallocatechin-3-gallate in acute glaucoma via the nuclear factor-κB signalling pathway.

Glaucoma is a disease involving impaired visual function accompanied by degeneration and necrosis of the optic nerve. Epigallocatechin-3-gallate (EGCG) exerts a neuroprotective effect against the degeneration of retinal ganglion cells. However, whether EGCG can relieve glaucoma and the possible mechanisms remain unclear. In order to determine the function of EGCG in glaucoma, an acute glaucoma rat model was established. Optic neuropathology was examined by haematoxylin-eosin staining and immunofluorescence staining for class III-β tubulin. The levels of inflammation-associated cytokines, such as interleukin (IL)-4, IL-6, TNF-α, IL-1β, IL-13 and IFN-γ were measured by flow cytometry. T cell proliferation was assessed by the carboxyfluorescein diacetate succinimidyl ester method. Finally, the functional role of EGCG in glaucoma was explored. The levels of the inflammation-associated proteins p-IκBα and p-p65 were measured by western blot analysis. The results showed that optic nerve injury occurred, and elevated levels of the inflammatory cytokines IL-4, IL-6, TNF-α, IL-1β, IL-13 and IFN-γ were observed in the rat model of acute glaucoma. In addition, an increased T lymphocyte proliferation rate and imbalance of Th1/Th2 cytokines were present in the models. Importantly, treatment with EGCG significantly alleviated optic nerve injury. At the molecular level, EGCG decreased the levels of inflammation-associated cytokines, decreased the proliferation rate of T lymphocyte cells, and repaired the imbalance of Th1/Th2 cytokines. Moreover, EGCG inhibited the increase in the phosphorylation of IκBα and p65 caused by modelling and thus suppressed the activation of the nuclear factor (NF)-κB signalling pathway. The findings of the present study indicate that EGCG could attenuate the symptoms of glaucoma and inhibit inflammatory responses by suppressing the NF-κB signalling pathway in a rat glaucoma model.

Critical Role of Protein Arginine Deiminase 4 in Mast Cell Extracellular Trap Formation Leading to Neuropathic Pain in Sickle Mice

Extracellular trap (ET) formation primarily meant to ensnare the pathogens, is also involved in sterile inflammation, platelet activation, impaired wound healing, oxidative stress, organ damage, etc (Jorch and Kubes, reviewed in Nat Med 2017). We have identified a novel role of mast cell ETs (MCETs) in contributing to neuropathic pain via Protein Arginine Deiminase 4 (PAD4), an enzyme that catalyzes chromatin decondensation in the nucleus by converting arginine to citrulline on histones. We used homozygous BERK sickle (HbSS) mice expressing human sickle hemoglobin (Hb) and control BERK (HbAA) mice expressing normal human HbA, and mast cells isolated from their dorsal skin. MCETs were visualized by laser scanning confocal microscopy in 100 μm thick dorsal skin sections and in mast cells in vitro with SYTO13 and SYTOX Orange (Invitrogen) and citrullinated histone antibodies (Abcam); and co-localized in the skin using mast cell-specific c-kit, FcεR1 and tryptase, nerve-fiber-specific anti-NF200 and anti-PGP9.5 and anti-CD31 for vasculature.We observed vibrant clusters of trap-shooting mast cells surrounding the vasculature and nerve fibers in the skin of sickle mice. The exuberant spread of MCETs and tryptase permeated the vessel lumen and may contribute to observed increase in circulating tryptase, DNA and endothelial activation in sickle mice. Notably, large aggregates of MCETs and mast cells appeared occluding blood vessels, and tightly surrounded the axonal nerve fibers demonstrating signs of injury and axonal sprouting, features underlying neuropathic pain. We stimulated mast cells in vitro with 40µM hemin for 2h after 2-hour priming with 1ng/ml TNFα to create a sickle microenvironment in vitro . SYTO13 and citrullinated histone staining showed that nearly all the cells from sickle but fewer cells from control mice showed MCET formation with hemin after priming with TNFα. Tubulin staining showed contraction and extension into long fibers in hemin/TNFα treated sickle mast cells, suggesting that ongoing hemolysis releasing free-heme in an inflammatory mileau in SCD may contribute to MCETosis observed in the skin of sickle mice. Transcripts of TLR4 and FcεR1 are significantly elevated in sickle compared to control mast cells (Vincent et al., Blood 2013). Silencing of TLR4 and/or FcεR1 did not inhibit hemin/TNFα-induced MCET formation completely. However, inhibition of PAD4 with 10µM GSK484 (Cayman) completely abrogated hemin/TNFα-induced MCET formation. Several signaling pathways including PKB/Akt, MAPK/ERK, p38MAPK and Syk were constitutively activated in sickle mast cells. Collectively, these in vitro observations suggest that multiple receptors and pathways converge at the downstream activation of PAD4 leading to MCETosis.Since MCETs incited direct peripheral nerve injury, we examined if inhibition of MCETs in vivo using PAD4 inhibitor would attenuate pain. Sickle and control mice were treated subcutaneously with PAD4 inhibitor GSK484 (20 mg/kg/day) or 0.9% saline for 30 days. GSK484 significantly reduced cold and heat hyperalgesia after 48h (p=.0066) and 72h (p=.0002), respectively, but reduced mechanical hyperalgesia significantly after 1 week (p=.0036) of treatment Vs baseline before treatment. Attenuation of hyperalgesia remained effective until 30 days, last day of treatment and observation, suggesting that mice do not develop analgesic tolerance. Mast cell degranulation was decreased by 90% in the skin (p=.0004); white blood cells and serum GM-CSF were significantly reduced (p= .010 and <.0001, respectively), but the hematocrit was significantly increased (p=.035) in sickle mice treated with GSK484 Vs saline. Skin secretagogue of GSK484 treated sickle mice showed about 50% reduction in inflammatory cytokines CCL2/MCP-1, TNFα and RANTES (p=.0229, .0154 and .0290, respectively Vs saline treated mice).Together, these data demonstrate an anti-inflammatory effect of GSK484 in the periphery and attenuation of neuropathic pain. Thus, mast cell degranulation and MCETosis contribute to inflammation and neurovascular injury leading to inflammatory as well as neuropathic pain. We speculate that MCETosis may also contribute to vascular dysfunction and organ damage in SCD. Thus, PAD4 inhibition provides a potential therapeutic target to attenuate the onset and progression of pain and perhaps other pathological consequences of SCD. DisclosuresGupta:Tautona Group: Consultancy, Honoraria; Fera Pharmaceuticals LLC: Consultancy, Honoraria.

PEDF Gene Deletion Disrupts Corneal Innervation and Ocular Surface Function.

PurposeThe cornea is richly innervated by the trigeminal ganglion (TG) and its function supported by secretions from the adjacent lacrimal (LG) and meibomian glands (MG). In this study we examined how pigment epithelium–derived factor (PEDF) gene deletion affects the cornea structure and function.MethodsWe used PEDF hemizygous and homozygous knockout mice to study effects of PEDF deficiency on corneal innervation assessed by beta tubulin staining, mRNA expression of trophic factors, and PEDF receptors by adjacent supporting glands, corneal sensitivity measured using a Cochet-Bonnet esthesiometer, and tear production using phenol red cotton thread wetting.ResultsLoss of PEDF was accompanied by reduced corneal innervation and sensitivity, increased corneal surface injury and tear production, thinning of the corneal stroma and loss of stromal cells. PEDF mRNA was expressed in the cornea and its supporting tissues, the TG, LG, and MG. Deletion of one or both PEDF alleles resulted in decreased expression of essential trophic support in the TG, LG, and MG including nerve growth factor, brain-derived neurotrophic growth factor, and GDNF with significantly increased levels of NT-3 in the LG and decreased EGF expression in the cornea. Decreased transcription of the putative PEDF receptors, adipose triglyceride lipase, lipoprotein receptor–related protein 6, laminin receptor, PLXDC1, and PLXDC2 was also evident in the TG, LG and MG with the first three showing increased levels in corneas of the Pedf+/− and Pedf−/− mice compared to wildtype controls. Constitutive inactivation of ERK1/2 and Akt was pronounced in the TG and cornea, although their protein levels were dramatically increased in Pedf−/− mice.ConclusionsThis study highlights an essential role for PEDF in corneal structure and function and confirms the reported rescue of exogenous PEDF treatment in corneal pathologies. The pleiotropic effects of PEDF deletion on multiple trophic factors, receptors and signaling molecules are strong indications that PEDF is a key coordinator of molecular mechanisms that maintain corneal function and could be exploited in therapeutic options for several ocular surface diseases.

Human Bronchial Epithelial Cell Growth on Homologous Versus Heterologous Tissue Extracellular Matrix

BackgroundExtracellular matrix (ECM) bioscaffolds produced by decellularization of source tissue have been effectively used for numerous clinical applications. However, decellularized tracheal constructs have been unsuccessful due to the immediate requirement of a functional airway epithelium on surgical implantation. ECM can be solubilized to form hydrogels that have been shown to support growth of many different cell types. The purpose of the present study is to compare the ability of airway epithelial cells to attach, form a confluent monolayer, and differentiate on homologous (trachea) and heterologous (urinary bladder) ECM substrates for potential application in full tracheal replacement. Materials and methodsPorcine tracheas and urinary bladders were decellularized. Human bronchial epithelial cells (HBECs) were cultured under differentiation conditions on acellular tracheal ECM and urinary bladder matrix (UBM) bioscaffolds and hydrogels and were assessed by histology and immunolabeling for markers of ciliation, goblet cell formation, and basement membrane deposition. ResultsBoth trachea and urinary bladder tissues were successfully decellularized. HBEC formed a confluent layer on both trachea and UBM scaffolds and on hydrogels created from these bioscaffolds. Cells grown on tracheal and UBM hydrogels, but not on bioscaffolds, showed positive-acetylated tubulin staining and the presence of mucus-producing goblet cells. Collagen IV immunolabeling showed basement membrane deposition by these cells on the surface of the hydrogels. ConclusionsECM hydrogels supported growth and differentiation of HBEC better than decellularized ECM bioscaffolds and show potential utility as substrates for promotion of a mature respiratory epithelium for regenerative medicine applications in the trachea.

Synthetic cyclopenta[b]indoles exhibit antineoplastic activity by targeting microtubule dynamics in acute myeloid leukemia cells

Acute promyelocytic leukemia (APL) is associated with PML-RARα oncogene, which is treated using all-trans retinoic acid (ATRA)-based chemotherapy. However, chemoresistance is observed in 20–30% of treated patients and represents a clinical challenge, raising the importance of the development of new therapeutic options. In the present study, the effects of three synthetic cyclopenta[b]indoles on the leukemia phenotype were investigated using NB4 (ATRA-sensitive) and NB4-R2 (ATRA-resistant) cells. Among the tested synthetic cyclopenta[b]indoles, compound 2, which contains a heterocyclic nucleus, was the most active, presenting time-dependent cytotoxic activity in the μM range in APL cells, without cytotoxicity for normal leukocytes, and was selected for further characterization. Compound 2 significantly decreased clonogenicity, increased apoptosis, and caused cell cycle arrest at S and G2/M phases in a drug concentration-dependent manner. Morphological analyses indicated aberrant mitosis and diffuse tubulin staining upon compound 2 exposure, which corroborates cell cycle findings. In the molecular scenario, compound 2 reduced STMN1 expression and activity, and induced PARP1 cleavage and H2AX and CHK2 phosphorylation, and modulated CDKN1A, PMAIP1, GADD45A, and XRCC3 expressions, indicating reduction of cell proliferation, apoptosis, and DNA damage. Moreover, in the in vivo tubulin polymerization assay, NB4 and NB4-R2 cells showed a reduction in the levels of polymerized tubulin upon compound 2 exposure, which indicates tubulin as a target of the drug. Molecular docking supports this hypothesis. Taken together, these data indicated that compound 2 exhibits antileukemic effects through disrupting the microtubule dynamics, identifying a possible novel potential antineoplastic agent for the treatment of ATRA-resistant APL.

Zero-valent iron nanoparticles containing nanofiber scaffolds for nerve tissue engineering.

Regeneration of nerve tissue is a challenging issue in regenerative medicine. Especially, the peripheral nerve defects related to the accidents are one of the leading health problems. For large degeneration of peripheral nerve, nerve grafts are used in order to obtain a connection. These grafts should be biodegradable to prevent second surgical intervention. In order to make more effective nerve tissue engineering materials, nanotechnological improvements were used. Especially, the addition of electrically conductive and biocompatible metallic particles and carbon structures has essential roles in the stimulation of nerves. However, the metabolizing of these structures remains to wonder because of their nondegradable nature. In this study, biodegradable and conductive nerve tissue engineering materials containing zero-valent iron (Fe) nanoparticles were developed and investigated under in vitro conditions. By using electrospinning technique, fibrous mats composed of electrospun poly(ε-caprolactone) (PCL) nanofibers and Fe nanoparticles were obtained. Both electrical conductivity and mechanical properties increased compared with control group that does not contain nanoparticles. Conductivity of PCL/Fe5 and PCL/Fe10 increased to 0.0041 and 0.0152 from 0.0013 Scm-1 , respectively. Cytotoxicity results indicated toxicity for composite mat containing 20% Fe nanoparticles (PCL/Fe20). SH-SY5Y cells were grown on PCL/Fe10 best, which contains 10% Fe nanoparticles. Beta III tubulin staining of dorsal root ganglion neurons seeded on mats revealed higher cell number on PCL/Fe10. This study demonstrated the impact of zero-valent Fe nanoparticles on nerve regeneration. The results showed the efficacy of the conductive nanoparticles, and the amount in the composition has essential roles in the promotion of the neurites.

Physical and immunological barrier of human primary nasal epithelial cells from non-allergic and allergic donors

The epithelial cell-derived cytokine milieu has been discussed as a “master switch” in the development of allergic disease.To understand the role of innate immune response in nasal epithelial cells during allergic inflammation, we created and established a fast and minimally invasive method to isolate and culture human nasal epithelial cells from clinically and immunologically well characterized patients. Human nasal epithelial cells from non-atopic volunteers and from allergic rhinitis patients were compared in respect to their growth, barrier integrity, pattern recognition, receptor expression, and immune responses to allergens and an array of pathogen-associated molecular patterns and inflammasome activators.Cells from nasal scrapings were clearly identified as nasal epithelial cells by staining of pan-Cytokeratin, Cytokeratin-14 and Tubulin. Additionally, Mucin 5AC staining revealed the presence of goblet cells, while staining of tight-junction protein Claudin-1, Occludin and ZO-1 showed the ability of the cells to form a tight barrier. Cells of atopic donors grew slower than cells of non-atopic donors. All nasal epithelial cells expressed TLR1-6 and 9, yet the expression of TLR-9 was lower in cells from allergic rhinitis (AR) donors. Additionally, epithelial cells from AR donors responded with a different TLR expression pattern to stimulation with TLR ligands. TLR-3 was the most potent modulator of cytokine and chemokine secretion in all human nasal epithelial cells (HNECs). The secretion of IL-1β, CCL-5, IL-8, IL-18 and IL-33 was elevated in HNECs of AR donors as compared to cells of non-atopic donors. This was observed in the steady-state (IL-18, IL-33) as well as under stimulation with TLR ligands (IL-18, IL-33, CCL-5, IL-8), aqueous pollen extracts (IL-18, IL-33), or the inflammasome activator Nigericin (IL-1β).In conclusion, nasal epithelial cells of AR donors show altered physical barrier responses in steady-state and in response to allergen stimulation. Cells of AR donors show increased expression of pro-inflammatory and IL-1 family cytokines at baseline and under stimulation, which could contribute to a micromilieu which is favorable for Th2.

Hypoxia-induced activity loss of a photo-responsive microtubule inhibitor azobenzene combretastatin A4

The conformation-dependent activity of azobenzene combretastatin A4 (Azo-CA4) provides a unique approach to reduce the side-effects of chemotherapy, due to the light-triggered conformation transition of its azobenzene moiety. Under hypoxic tumor microenvironment, however, the high expression of azoreductase can reduce azobenzene to aniline. It was postulated that the Azo-CA4 might be degraded under hypoxia, resulting in the decrease of its anti-tumor activity. The aim of this study was to verify such hypothesis in HeLa cells in vitro. The quantitative drug concentration analysis shows the ratio-metric formation of degradation end-products, confirming the bioreduction of Azo-CA4. The tubulin staining study indicates that Azo-CA4 loses the potency of switching off microtubule dynamics under hypoxia. Furthermore, the cell cycle analysis shows that the ability of Azo-CA4 to induce mitotic arrest is lost at low oxygen content. Therefore, the cytotoxicity of Azo-CA4 is compromised under hypoxia. In contrast, combretastatin A4 as a positive control maintains the potency to inhibit tubulin polymerization and break down the nuclei irrespective of light irradiation and oxygen level. This work highlights the influence of hypoxic tumor microenvironment on the anti-tumor potency of Azo-CA4, which should be considered during the early stage of designing translational Azo-CA4 delivery systems.

Lineage tracing suggests that ovarian endosalpingiosis does not result from escape of oviductal epithelium.

Most high-grade serous carcinomas are thought to arise from Fallopian tube epithelium (FTE), but some likely arise outside of the tube, perhaps from ectopic tubal-type epithelium known as endosalpingiosis. Importantly, the origin of endosalpingiosis is poorly understood. The proximity of the tubal fimbriae to the ovaries has led to the proposal that disruptions in the ovarian surface that occur during ovulation may allow detached FTE to implant in the ovary and form tubal-type glands and cysts. An alternative model suggests that cells present in ectopic locations outside the Müllerian tract retain the capacity for multi-lineage differentiation and can form glands with tubal-type epithelium. We used double transgenic Ovgp1-iCreERT2 ;R26RLSL-eYFP mice, which express an eYFP reporter protein in OVGP1-positive tissues following transient tamoxifen (TAM) treatment, to track the fate of oviductal epithelial cells. Cohorts of adult mice were given TAM to activate eYFP expression in oviductal epithelium, and ovaries were examined at time points ranging from 2 days to 12 months post-TAM. To test whether superovulation might increase acquisition of endosalpingiosis, additional cohorts of TAM-treated mice underwent up to five cycles of superovulation and ovaries were examined at 1, 6, and 12 months post-TAM. Ovaries were sectioned in their entirety to identify endosalpingiosis. Immunohistochemical staining for PAX8, tubulin, OVGP1, and eYFP was employed to study endosalpingiosis lesions. Ovarian endosalpingiosis was identified in 14.2% of TAM-treated adult mice. The endosalpingiotic inclusion glands and cysts were lined by secretory and ciliated cells and expressed PAX8, tubulin, OVGP1, and eYFP. Neither age nor superovulation was associated with a significant increase in endosalpingiosis. Endosalpingiosis was also occasionally present in the ovaries of pre-pubertal mice. The findings imply that ovarian endosalpingiosis in the mouse does not likely arise as a consequence of detachment and implantation of tubal epithelium and other mechanisms may be relevant. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Corneal nerve healing after in situ laser nerve transection.

PurposeWe have previously reported that lamellar dissection of the cornea transects stromal nerves, and that regenerating neurites form a dense net along the surgical plane. In these experiments, we have disrupted the stromal nerve trunks in situ, without incising the cornea, to determine the regeneration events in the absence of a surgical plane.MethodsThy1-YFP mice were anesthetized and in vivo images of the corneal nerves were obtained with a wide-field stereofluorescent microscope. A far infrared XYRCOS Laser attached to 20X objective of an upright microscope was used to perform in situ transection of the stromal nerves. 3 types of laser transections were performed (n = 5/group): (i) point transection (a single cut); (ii) segmental transection (two cuts enclosing a segment of nerve trunk); and (iii) annular transection (cuts on all nerve trunks crossing the perimeter of a 0.8 mm diameter circular area centered on the corneal apex). Mice were imaged sequentially for 4 weeks thereafter to assess nerve degeneration (disappearance or weakening of original fluorescence intensity) or regeneration (appearance of new fluorescent fronds). Beta-3-tubulin immunostaining was performed on corneal whole-mounts to demonstrate nerve disruption.ResultsThe pattern of stromal nerves in corneas of the same mouse and in corneas of littermates was dissimilar. Two distinct patterns were observed, often within the same cornea: (i) interconnected trunks that spanned limbus to limbus; or (ii) dichotomously branching trunks that terminate at the corneal apex. Point transections did not cause degeneration of proximal or distal segment in interconnected trunks, but resulted in degeneration of distal segment of branching trunks. In segmental transections, the nerve segment enclosed within the two laser cuts degenerated. Lack of beta-3 tubulin staining at transection site confirmed nerve transection. In interconnected trunks, at 4 weeks, a hyperfluorescent plaque filled the gap created by the transection. In annular transections, some nerve trunks degenerated, while others regained or retained fluorescence.ConclusionsInterconnected stromal nerves in murine corneas do not degenerate after in situ point transection and show evidence of healing at the site of disruption. Presence or absence of a surgical plane influences corneal nerve regeneration after transection.