Discovery and Preclinical Pharmacology of an Oral Bromodomain and Extra-Terminal (BET) Inhibitor Using Scaffold-Hopping and Structure-Guided Drug Design.

Inhibition of the bromodomain and extra-terminal (BET) family of adaptor proteins is an attractive strategy for targeting transcriptional regulation of key oncogenes, such as c-MYC. Starting with the screening hit , a combination of structure-activity relationship and protein structure-guided drug design led to the discovery of a differently oriented carbazole with favorable binding to the tryptophan, proline, and phenylalanine (WPF) shelf conserved in the BET family. Identification of an additional lipophilic pocket and functional group optimization to optimize pharmacokinetic (PK) properties culminated in the discovery of (BMS-986158) with excellent potency in binding and functional assays.

Sub/supercritical Fluid Chromatography Purification and Desalting of a Cyclic Dinucleotide STING Agonist.

An efficient and "endotoxin-free" purification of a cyclic dinucleotide (CDN) STING agonist was achieved to produce multigram quantities of pure BMT-390025, an active pharmaceutical ingredient (API), for toxicological studies. A two-step sub/supercritical fluid chromatography (SFC) procedure was developed for the achiral purification and desalting of the polar ionic CDN. A robust SFC process employing methanol-acetonitrile-water with ammonium acetate as co-solvent in CO on BEH 2-ethylpyridine was established and scaled up as the first step to achieve a successful purification.

The effect of water on the large-scale supercritical fluid chromatography purification of two factor XIa active pharmaceutical ingredients.

BMS-962212, a parenteral Factor XIa inhibitor, was scaled-up for toxicity studies. Two steps of supercritical fluid chromatography (SFC) were developed for the chiral resolution of the penultimate and achiral purification of final active pharmaceutical ingredient (API), BMS-962212. A robust SFC process using Chiralcel OD-H with methanol-acetonitrile as modifier in CO was established to achieve a stable and uninterrupted operation with reduced mobile phase viscosity and system pressure drop.

Large-scale supercritical fluid chromatography purification of unstable STING agonist intermediates.

A regioisomeric mixture of the nucleoside derivative, Intermediate 1, required resolution by preparative supercritical fluid chromatography (SFC) in order to obtain the desired regioisomer as a key intermediate in a STING agonist program. Various chiral columns and solvents including methanol, acetonitrile, isopropanol, and the mixture of acetonitrile and isopropanol as organic modifiers in carbon dioxide at different temperatures were screened to obtain the best regioisomeric resolution. A key issue associated with interconversion between the regioisomers via silyl migration during purification was investigated in methanol, acetonitrile, and the mixture of acetonitrile and isopropanol, and the optimal organic modifier in CO was established to mitigate the interconversion to an acceptable level (<5%).

Reverse-phase HPLC purification for an extremely unstable glucuronide metabolite.

A pure β-​D-​Glucopyranosiduronic acid metabolite (≥98.0 % purity and a single impurity ≤0.50 %) was requested for biological studies.

Humanized mice for immune checkpoint blockade in human solid tumors.

Immunotherapy, specifically research involving immune checkpoint blockers (ICBs), has become a popular trend in anticancer research over the last three years. Due to the difficulties and often poor translation of results from models, models have become more relevant than ever. With the discovery of NOD, , and mutations, patient-derived xenograft (PDX) mouse models were developed, providing an ideal environment for ICBs testing.

Downregulation of Aquaporin 9 Exacerbates Beta-amyloid-induced Neurotoxicity in Alzheimer's Disease Models In vitro and In vivo.

Alzheimer's disease (AD) is the most common cause of dementia in the elderly, characterized by progressive cognitive dysfunction. Aquaporin 9 (AQP9) is an aquaglyceroporin membrane channel shown biophysically to conduct water, glycerol, and other small solutes. In our study, we reported for the first time an age-associated decrease in AQP9 mRNA and protein expressions in both hippocampus and cerebral cortex of APPswe/PS1dE9 (Tg) AD mice at 3, 6 and 10 months of age.

Retinal stem cells and regeneration of vision system.

The vertebrate retina is a well-characterized model for studying neurogenesis. Retinal neurons and glia are generated in a conserved order from a pool of mutlipotent progenitor cells. During retinal development, retinal stem/progenitor cells (RPC) change their competency over time under the influence of intrinsic (such as transcriptional factors) and extrinsic factors (such as growth factors).

Mining data on usage of electronic nicotine delivery systems (ENDS) from YouTube videos.

Objective: The objective was to analyse and compare puff and exhalation duration for individuals using electronic nicotine delivery systems (ENDS) and conventional cigarettes in YouTube videos.

Methods: Video data from YouTube videos were analysed to quantify puff duration and exhalation duration during use of conventional tobacco-containing cigarettes and ENDS. For ENDS, comparisons were also made between 'advertisers' and 'non-advertisers', genders, brands of ENDS, and models of ENDS within one brand.

Neuroprotective signaling mechanisms of telomerase are regulated by brain-derived neurotrophic factor in rat spinal cord motor neurons.

Telomerase can promote neuron survival and can be regulated by growth factors such as brain-derived neurotrophic factor (BDNF). Increases of BDNF expression and telomerase activity after brain injury suggest that telomerase may be involved in BDNF-mediated neuroprotection. We investigated BDNF regulation of telomerase in rat spinal cord motor neurons (SMNs).

Regulation of retinal progenitor cell differentiation by bone morphogenetic protein 4 is mediated by the smad/id cascade.

PURPOSE. Bone morphogenetic proteins (BMPs) are secreted signaling molecules that are implicated in the control of multiple events during mouse eye development. However, little is known about the mechanisms by which BMP signaling regulates these retinal developmental processes.

Bone morphogenetic proteins mediate cellular response and, together with Noggin, regulate astrocyte differentiation after spinal cord injury.

Bone morphogenetic proteins (BMPs) play a critical role in regulating cell fate determination during central nervous system (CNS) development. In light of recent findings that BMP-2/4/7 expressions are upregulated after spinal cord injury, we hypothesized that the BMP signaling pathway is important in regulating cellular composition in the injured spinal cord. We found that BMP expressions were upregulated in neural stem cells (NSCs), neurons, oligodendrocytes and microglia/macrophages.

Effects of bone morphogenetic protein 2 on Id expression and neuroblastoma cell differentiation.

Bone morphogenetic proteins (BMPs) are secretory signal molecules that have a variety of regulatory functions during embryonic morphogenesis. BMP2 has been shown to induce differentiation in many cell types, mediated through the activation of its target genes: the inhibitors of differentiation (Id1-3) and key transcription factors. In this study, we investigated the effects of BMP2 on mouse neuroblastoma (Neuro2a) cell differentiation and regulation of the expression of Id1-3 and neural-specific transcription factors.

Molecular cloning and characterization of the zebrafish (Danio rerio) telomerase catalytic subunit (telomerase reverse transcriptase, TERT).

Telomerase is an enzyme composed of a catalytic subunit (TERT) and RNA template (TR), which specifically elongates telomeres and prevents cellular senescence. Although telomerase cannot be detected in most human somatic tissues, including the nervous system, it can be detected in teleost tissues. To facilitate the investigation of telomerase function in the teleost visual system, the coding sequence of zebrafish TERT is revealed and cloned.

Expression of telomerase reverse transcriptase in adult goldfish retina.

Telomerase, a specialized reverse transcriptase that maintains telomere during cell division, is commonly associated with cell proliferation. Increasing evidence suggests that telomerase may bear functions other than telomere elongation. We investigated whether telomerase is expressed in the continuously growing goldfish retina.

A neuroprotective herbal mixture inhibits caspase-3-independent apoptosis in retinal ganglion cells.

It was previously demonstrated that Menta-FX, a mixture of Panax quinquefolius L. (PQE), Ginkgo biloba (GBE), and Hypericum perforatum extracts (HPE), enhances retinal ganglion cell survival after axotomy. However, the mechanisms of neuroprotection remain unknown.

Endothelial nitric oxide synthase is expressed in amacrine cells of developing human retinas.

Purpose: To examine the expression and cellular distribution pattern of endothelial nitric oxide synthase (eNOS) in the developing human retina and to compare its expression with that in rats.

Methods: Expression of eNOS was examined by immunohistochemistry in retinas of humans ranging from 8.5 to 28 weeks of gestation (WG) and of rats.

Different optic nerve injury sites result in different responses of retinal ganglion cells to brain-derived neurotrophic factor but not neurotrophin-4/5.

In this study, we investigated whether brain-derived neurotrophic factor (BDNF) and neurotrophin-4/5 (NT-4/5) can achieve prolonged protection on retinal ganglion cells (RGCs) and whether site of axon injury modulates RGC response to neurotrophins. Two optic nerve (ON) injury paradigms, proximal and distal transections, were used. Autologous sciatic nerves were grafted onto ON stump in some animals to provide a suitable environment for axons to regrow.

CNTF and BDNF have similar effects on retinal ganglion cell survival but differential effects on nitric oxide synthase expression soon after optic nerve injury.

Purpose: To investigate the effect of ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) on retinal ganglion cell (RGC) survival and nitric oxide synthase (NOS) expression in the retina during the early phase of optic nerve (ON) injury, and to examine whether intraperitoneal application of the NOS scavenger nitro-l-arginine (l-NA) could protect the injured RGCs.

Methods: RGCs were retrogradely labeled with granular blue 3 days before the ON was intraorbitally transected. RGC survival was examined 1 week after ON transection and intraocular injection of CNTF and/or BDNF, or 1 to 2 weeks after daily intraperitoneal injection of the NOS inhibitor l-NA.

Intravitreal transplants of Schwann cells and fibroblasts promote the survival of axotomized retinal ganglion cells in rats.

Schwann cells (SCs) are considered one of the major cellular components to maintain the integrity of the peripheral nervous system (PNS) neurons after injury. Intravitreal transplant of peripheral nerves or Schwann cells has been shown to enhance the regenerative ability of retinal ganglion cells (RGCs). In the present study, we compared the effects of intravitreal transplants of Schwann cells and fibroblasts, two major components of peripheral nerves, on the survival of retinal ganglion cells in adult rats after optic nerve (ON) transection.

Synergistic effect of Nogo-neutralizing antibody IN-1 and ciliary neurotrophic factor on axonal regeneration in adult rodent visual systems.

The presence of Nogo axon regeneration inhibitory molecules in the central nervous system (CNS) and the counteracting effect of IN-1 antibodies have been widely reported. In this study, we examined the effect of IN-1-producing hybridoma cells on axon regeneration in adult rodent retinal ganglion cells (RGCs) after various types of optic nerve (ON) injury, evaluating therein whether ciliary neurotrophic factor (CNTF) potentiated the effect of IN-1. We found that application of IN-1 alone failed to enhance regeneration of intracranially or intraorbitally transected RGC axons in a peripheral nerve (PN) graft.

Regulation of caspase activation in axotomized retinal ganglion cells.

Transection of the optic nerve initiates massive death of retinal ganglion cells (RGCs). Interestingly, despite the severity of the injury, RGC loss was not observed until several days after axotomy. The mechanisms responsible for this initial lack of RGC death remained unknown.

CNTF promotes survival of retinal ganglion cells after induction of ocular hypertension in rats: the possible involvement of STAT3 pathway.

We examined the neuroprotective effect of ciliary neurotrophic factor (CNTF) on retinal ganglion cells (RGCs) in a rat glaucoma model with increased intraocular pressure (IOP) and studied the CNTF-mediated activation of Janus kinase/signal transducer and activator of transcription (JAK-STAT) pathway. Elevated IOP was induced by laser photocoagulation of the episcleral and limbal veins. The survival of RGCs was studied using Fluoro-Gold labelled in ocular hypertensive eyes with or without CNTF intravitreal injection.

c-Jun expression in surviving and regenerating retinal ganglion cells: effects of intravitreal neurotrophic supply.

Purpose: To investigate c-jun expression in surviving and axon-regenerating retinal ganglion cells (RGCs) and the effect of intravitreal neurotrophic supply on c-jun expression.

Methods: All animals underwent optic nerve transection (ONT) 0.5 mm behind the eyeball.

Inhibition of caspases promotes long-term survival and reinnervation by axotomized spinal motoneurons of denervated muscle in newborn rats.

We examined whether (1) a pan-caspase inhibitor, Boc-D-FMK, exerts long-term neuroprotective effects on spinal motoneurons (MNs) after root avulsion in neonatal rats and (2) whether the rescued spinal MNs regenerate their axons into a peripheral nerve (PN) graft and reinnervate a previously denervated target muscle. Eight weeks after root avulsion, 67% of spinal MNs remained in the Boc-D-FMK-treated group, whereas all MNs died in the sham control group. By 12 weeks postinjury, however, all Boc-D-FMK treated MNs died.