Patients with alcohol-related liver disease hospitalized during the COVID-19 pandemic experienced worse outcomes.

INTRODUCTION AND OBJECTIVES: Psychosocial stressors related to the coronavirus-19 (COVID-19) pandemic increased alcohol consumption. The effect on patients with alcohol-related liver diseases remains unclear. MATERIALS AND METHODS: Hospitalizations at a tertiary care center due to alcohol-related liver disease from March 1 through August 31 in 2019 (pre-pandemic cohort) and 2020 (pandemic cohort) were reviewed retrospectively. Differences in patient demographics, disease features, and outcomes were estimated in patients with alcoholic hepatitis utilizing T-tests, Mann-Whitney tests, Chi-square and Fisher Exact Tests and Anova models and logistic regression models in patients with alcoholic cirrhosis. RESULTS: 146 patients with alcoholic hepatitis and 305 patients with alcoholic cirrhosis were admitted during the pandemic compared to 75 and 396 in the pre-pandemic cohort. Despite similar median Maddrey Scores (41.20 vs. 37.45, p=0.57), patients were 25% less likely to receive steroids during the pandemic. Patients with alcoholic hepatitis admitted during the pandemic were more likely to have hepatic encephalopathy (0.13; 95% CI:0.01, 0.25), variceal hemorrhage (0.14; 95% CI:0.04, 0.25), require oxygen (0.11; 95% CI:0.01, 0.21), vasopressors (OR:3.49; 95% CI:1.27, 12.01) and hemodialysis (OR:3.70; 95% CI:1.22, 15.13). On average, patients with alcoholic cirrhosis had MELD-Na scores 3.77 points higher (95% CI:1.05, 13.46) as compared to the pre-pandemic and had higher odds of experiencing hepatic encephalopathy (OR:1.34; 95% CI:1.04, 1.73), spontaneous bacterial peritonitis (OR:1.88; 95% CI:1.03, 3.43), ascites (OR:1.40, 95% CI:1.10, 1.79), vasopressors (OR:1.68, 95% CI:1.14, 2.46) or inpatient mortality (OR:2.00, 95% CI:1.33, 2.99) than the pre-pandemic. CONCLUSIONS: Patients with alcohol-related liver disease experienced worse outcomes during the pandemic.

A Scalable Platform for Producing Recombinant Nucleosomes with Codified Histone Methyltransferase Substrate Preferences.

Wolf-Hirschhorn Syndrome Candidate 1 (WHSC1; also known as NSD2) is a SET domain-containing histone lysine methyltransferase. A chromosomal translocation occurs in 15-20% of multiple myeloma patients and is associated with increased production of WHSC1 and poor clinical prognosis. To define the substrate requirements of NSD2, we established a platform for the large-scale production of recombinant polynucleosomes, based on authentic human histone proteins, expressed in E. coli, and complexed with linearized DNA. A brief survey of methyltransferases whose substrate requirements are recorded in the literature yielded expected results, lending credence to the fitness of our approach. This platform was readily 'codified' with respect to both position and extent of methylation at histone 3 lysines 18 and 36 and led to the conclusion that the most readily discernible activity of NSD2 in contact with a nucleosome substrate is dimethylation of histone 3 lysine 36. We further explored reaction mechanism, and conclude a processive, rather than distributive mechanism best describes the interaction of NSD2 with intact nucleosome substrates. The methods developed feature scale and flexibility and are suited to thorough pharmaceutical-scale drug discovery campaigns.

Allosteric Wip1 phosphatase inhibition through flap-subdomain interaction.

Although therapeutic interventions of signal-transduction cascades with targeted kinase inhibitors are a well-established strategy, drug-discovery efforts to identify targeted phosphatase inhibitors have proven challenging. Herein we report a series of allosteric, small-molecule inhibitors of wild-type p53-induced phosphatase (Wip1), an oncogenic phosphatase common to multiple cancers. Compound binding to Wip1 is dependent on a 'flap' subdomain located near the Wip1 catalytic site that renders Wip1 structurally divergent from other members of the protein phosphatase 2C (PP2C) family and that thereby confers selectivity for Wip1 over other phosphatases. Treatment of tumor cells with the inhibitor GSK2830371 increases phosphorylation of Wip1 substrates and causes growth inhibition in both hematopoietic tumor cell lines and Wip1-amplified breast tumor cells harboring wild-type TP53. Oral administration of Wip1 inhibitors in mice results in expected pharmacodynamic effects and causes inhibition of lymphoma xenograft growth. To our knowledge, GSK2830371 is the first orally active, allosteric inhibitor of Wip1 phosphatase.

Hospital Trends of Acute Pancreatitis During the Coronavirus Disease 2019 Pandemic.

OBJECTIVE: The coronavirus disease 2019 pandemic led to changes in individuals' behaviors and healthcare delivery. We examined the impact of these changes on the rates and clinical course of acute pancreatitis (AP). METHODS: Hospitalizations for AP from March 1 through August 31 in 2019 (baseline group) and the same period in 2020 (pandemic group) were retrospectively reviewed. Univariate and multivariate analyses were used for demographics and outcomes. RESULTS: Two hundred eighty subjects (315 admissions) were identified in 2019 and 237 subjects (264 admissions) in 2020. Subjects in the pandemic group were more likely to have systemic inflammatory response syndrome (40% vs 25%, P < 0.01), pancreatic necrosis (14% vs 10%, P = 0.03), and persistent organ failure (17% vs 9%, P = 0.01) compared with prepandemic. There was no difference in etiology of AP. A multivariable model indicates that increased comorbidities, prior pancreatitis, pancreatic necrosis, and prescription of opiates at discharge were associated with 30-day readmissions during the pandemic. CONCLUSIONS: Fewer patients were admitted for AP during the pandemic, suggesting that patients with milder symptoms avoided hospital interaction. Practices followed during the pandemic, especially avoidance of hospitalization and improved efficiency of hospital management, may reduce the burden of pancreatitis care in the future.

Baculovirus production of fully-active phosphoinositide 3-kinase alpha as a p85alpha-p110alpha fusion for X-ray crystallographic analysis with ATP competitive enzyme inhibitors.

Phosphoinositide 3-kinases have been targeted for therapeutic research because they are key components of a cell signaling cascade controlling proliferation, growth, and survival. Direct activation of the PI3Kalpha pathway contributes to the development and progression of solid tumors in breast, endometrial, colon, ovarian, and gastric cancers. In the context of a drug discovery effort, the availability of a robust crystallographic system is a means to understand the subtle differences between ATP competitive inhibitor interactions with the active site and their selectivity against other PI3Kinase enzymes. To generate a suitable recombinant design for this purpose, a p85alpha-p110alpha fusion system was developed which enabled the expression and purification of a stoichiometrically homogeneous, constitutively active enzyme for structure determination with potent ATP competitive inhibitors (Raha et al., in preparation) [56]. This approach has yielded preparations with activity and inhibition characteristics comparable to those of the full-length PI3Kalpha from which X-ray diffracting crystals were grown with inhibitors bound in the active site.

Effects of oncogenic p110alpha subunit mutations on the lipid kinase activity of phosphoinositide 3-kinase.

The PIK3CA gene, encoding the p110alpha catalytic subunit of Class IA PI3Ks (phosphoinositide 3-kinases), is frequently mutated in many human tumours. The three most common tumour-derived alleles of p110alpha, H1047R, E542K and E545K, were shown to potently activate PI3K signalling in human epithelial cells. In the present study, we examine the biochemical activity of the recombinantly purified PI3K oncogenic mutants. The kinetic characterizations of the wt (wild-type) and the three 'hot spot' PI3K mutants show that the mutants all have approx. 2-fold increase in lipid kinase activities. Interestingly, the phosphorylated IRS-1 (insulin receptor substrate-1) protein shows activation of the lipid kinase activity for the wt and H1047R but not E542K and E545K PI3Kalpha, suggesting that these mutations represent different mechanisms of lipid kinase activation and hence transforming activity in cancer cells.

Characterization of PI3K class IA isoforms with regulatory subunit p55alpha using a scintillation proximity assay.

Differential activation of the phosphoinositide 3-kinase (PI3K)/AKT pathway has been linked to cancer. Activation occurs through gene amplification and activating mutations. High-frequency mutations in the gene encoding the p110alpha catalytic subunit of PI3K (PIK3CA) have been observed in a variety of tumors including colon, brain, breast, ovarian, and gastric. Inhibition of PI3K kinase activity may provide a specific way to treat multiple types of human cancer. A scintillation proximity assay (SPA) was developed to detect phosphatidylinositol 3-kinase catalytic activity. Using this assay format, steady-state kinetic parameters were compared for the PI3K class IA enzymes p110alpha, p110beta, and p110delta, each coexpressed with the regulatory subunit p85alpha or splice variant p55alpha. Inhibition by the natural product wortmannin and LY294002 was detected with potencies consistent with alternate assay formats. Other biochemical assay formats have been described for phosphoinositide 3-kinases but each has its unique limitations. The simple, inexpensive, sensitive high-throughput nature of the SPA format has advanced our knowledge of isoform-specific enzymology and will facilitate the discovery of novel PI3K inhibitors.

A molecular signature for delayed graft function.

Chronic kidney disease and associated comorbidities (diabetes, cardiovascular diseases) manifest with an accelerated ageing phenotype, leading ultimately to organ failure and renal replacement therapy. This process can be modulated by epigenetic and environmental factors which promote loss of physiological function and resilience to stress earlier, linking biological age with adverse outcomes post-transplantation including delayed graft function (DGF). The molecular features underpinning this have yet to be fully elucidated. We have determined a molecular signature for loss of resilience and impaired physiological function, via a synchronous genome, transcriptome and proteome snapshot, using human renal allografts as a source of healthy tissue as an in vivo model of ageing in humans. This comprises 42 specific transcripts, related through IFNγ signalling, which in allografts displaying clinically impaired physiological function (DGF) exhibited a greater magnitude of change in transcriptional amplitude and elevated expression of noncoding RNAs and pseudogenes, consistent with increased allostatic load. This was accompanied by increased DNA methylation within the promoter and intragenic regions of the DGF panel in preperfusion allografts with immediate graft function. Pathway analysis indicated that an inability to sufficiently resolve inflammatory responses was enabled by decreased resilience to stress and resulted in impaired physiological function in biologically older allografts. Cross-comparison with publically available data sets for renal pathologies identified significant transcriptional commonality for over 20 DGF transcripts. Our data are clinically relevant and important, as they provide a clear molecular signature for the burden of "wear and tear" within the kidney and thus age-related physiological capability and resilience.

Highly potent inhibitors of methionine aminopeptidase-2 based on a 1,2,4-triazole pharmacophore.

High-throughput screening for inhibitors of the human metalloprotease, methionine aminopeptidase-2 (MetAP2), identified a potent class of 3-anilino-5-benzylthio-1,2,4-triazole compounds. Efficient array and interative synthesis of triazoles led to rapid SAR development around the aniline, benzylthio, and triazole moeities. Evaluation of these analogs in a human MetAP2 enzyme assay led to the identification of several inhibitors with potencies in the 50-100 picomolar range. The deleterious effects on inhibitor potency by methylation of the anilino-triazole nitrogens, as well as the X-ray crystal structure of triazole 102 bound in the active site of MetAP2, confirm the key interactions between the triazole nitrogens, the active site cobalt atoms, and the His-231 side-chain. The structure has also provided a rationale for interpreting SAR within the triazole series. Key aniline (2-isopropylphenyl) and sulfur substituents (furanylmethyl) identified in the SAR studies led to the identification of potent inhibitors (103 and 104) of endothelial cell proliferation. Triazoles 103 and 104 also exhibited dose-dependent activity in an aortic ring tissue model of angiogenesis highlighting the potential utility of MetAP2 inhibitors as anticancer agents.

Development of dihydropyridone indazole amides as selective Rho-kinase inhibitors.

Rho kinase (ROCK1) mediates vascular smooth muscle contraction and is a potential target for the treatment of hypertension and related disorders. Indazole amide 3 was identified as a potent and selective ROCK1 inhibitor but possessed poor oral bioavailability. Optimization of this lead resulted in the discovery of a series of dihydropyridones, exemplified by 13, with improved pharmacokinetic parameters relative to the initial lead. Indazole substitution played a critical role in decreasing clearance and improving oral bioavailability.

Discovery of aminofurazan-azabenzimidazoles as inhibitors of Rho-kinase with high kinase selectivity and antihypertensive activity.

The discovery, proposed binding mode, and optimization of a novel class of Rho-kinase inhibitors are presented. Appropriate substitution on the 6-position of the azabenzimidazole core provided subnanomolar enzyme potency in vitro while dramatically improving selectivity over a panel of other kinases. Pharmacokinetic data was obtained for the most potent and selective examples and one (6n) has been shown to lower blood pressure in a rat model of hypertension.

A high-throughput screen measuring ubiquitination of p53 by human mdm2.

Tumor suppressor p53 is typically maintained at low levels in normal cells. In response to cellular stresses, such as DNA damage, p53 is stabilized and can stimulate responses leading to cell cycle arrest or apoptosis. Corresponding to its central role in preventing propagation of damaged cells, mutation or deletion of p53 is found in nearly 50% of all human tumors. Mdm2 (mouse-d-minute 2) and its human ortholog (hmdm2 or hdm2) catalyze the ubiquitination of p53, targeting it for degradation via the proteosome. Thus, the activity of mdm2 is inversely correlated with p53 levels. Based on this, inhibition of human mdm2 activity by a small-molecule therapeutic will lead to net stabilization of p53 and be the basis for development of a novel cancer therapeutic. Previous high-throughput screening assays of mdm2 measured the autoubiquitination activity of mdm2, which occurs in the absence of an acceptor substrate such as p53. The major drawback to this approach is that inhibitors of mdm2 autoubiquitination may lead to a net stabilization of mdm2 and thus have the opposite effect of inhibitors that interfere with p53 ubiquitination. The authors describe the development, validation, and execution of a high-throughput screening measuring the ubiquitination of p53 by mdm2, with p53 labeled with europium and the other substrate (Ub-UbcH5b) labeled with a Cy5 on the ubiquitin. After confirming that known inhibitors are detected with this assay, it was successfully automated and used to query >600,000 compounds from the GlaxoSmithKline collection for mdm2 inhibitors.

Activation of the Amino Acid Response Pathway Blunts the Effects of Cardiac Stress.

BACKGROUND: The amino acid response (AAR) is an evolutionarily conserved protective mechanism activated by amino acid deficiency through a key kinase, general control nonderepressible 2. In addition to mobilizing amino acids, the AAR broadly affects gene and protein expression in a variety of pathways and elicits antifibrotic, autophagic, and anti-inflammatory activities. However, little is known regarding its role in cardiac stress. Our aim was to investigate the effects of halofuginone, a prolyl-tRNA synthetase inhibitor, on the AAR pathway in cardiac fibroblasts, cardiomyocytes, and in mouse models of cardiac stress and failure. METHODS AND RESULTS: Consistent with its ability to inhibit prolyl-tRNA synthetase, halofuginone elicited a general control nonderepressible 2-dependent activation of the AAR pathway in cardiac fibroblasts as evidenced by activation of known AAR target genes, broad regulation of the transcriptome and proteome, and reversal by l-proline supplementation. Halofuginone was examined in 3 mouse models of cardiac stress: angiotensin II/phenylephrine, transverse aortic constriction, and acute ischemia reperfusion injury. It activated the AAR pathway in the heart, improved survival, pulmonary congestion, left ventricle remodeling/fibrosis, and left ventricular function, and rescued ischemic myocardium. In human cardiac fibroblasts, halofuginone profoundly reduced collagen deposition in a general control nonderepressible 2-dependent manner and suppressed the extracellular matrix proteome. In human induced pluripotent stem cell-derived cardiomyocytes, halofuginone blocked gene expression associated with endothelin-1-mediated activation of pathologic hypertrophy and restored autophagy in a general control nonderepressible 2/eIF2α-dependent manner. CONCLUSIONS: Halofuginone activated the AAR pathway in the heart and attenuated the structural and functional effects of cardiac stress.

Tunneling Nanotubes and Gap Junctions-Their Role in Long-Range Intercellular Communication during Development, Health, and Disease Conditions.

Cell-to-cell communication is essential for the organization, coordination, and development of cellular networks and multi-cellular systems. Intercellular communication is mediated by soluble factors (including growth factors, neurotransmitters, and cytokines/chemokines), gap junctions, exosomes and recently described tunneling nanotubes (TNTs). It is unknown whether a combination of these communication mechanisms such as TNTs and gap junctions may be important, but further research is required. TNTs are long cytoplasmic bridges that enable long-range, directed communication between connected cells. The proposed functions of TNTs are diverse and not well understood but have been shown to include the cell-to-cell transfer of vesicles, organelles, electrical stimuli and small molecules. However, the exact role of TNTs and gap junctions for intercellular communication and their impact on disease is still uncertain and thus, the subject of much debate. The combined data from numerous laboratories indicate that some TNT mediate a long-range gap junctional communication to coordinate metabolism and signaling, in relation to infectious, genetic, metabolic, cancer, and age-related diseases. This review aims to describe the current knowledge, challenges and future perspectives to characterize and explore this new intercellular communication system and to design TNT-based therapeutic strategies.

Expression, purification, and characterization of an enzymatically active truncated human rho-kinase I (ROCK I) domain expressed in Sf-9 insect cells.

Rho Kinase I (ROCK I) is a serine/threonine kinase that is involved in diverse cellular signaling. To further understand the physiological role of ROCK I and to identify and develop potent and selective inhibitors of ROCK I, we have overexpressed and purified a constitutively active dimeric human ROCK I (3-543) kinase domain using the Sf9-baculovirus expression system. In addition, using a limited proteolysis technique, we have identified a minimal functional subdomain of ROCK I that can be used in crystallization studies. The availability of multimilligram amounts of purified and well characterized functional human ROCK I kinase domains will be useful in screening and structural studies.

4-Aryl-1,2,3-triazole: a novel template for a reversible methionine aminopeptidase 2 inhibitor, optimized to inhibit angiogenesis in vivo.

Inhibitors of human methionine aminopeptidase type 2 (hMetAP2) are of interest as potential treatments for cancer. A new class of small molecule reversible inhibitors of hMetAP2 was discovered and optimized, the 4-aryl-1,2,3-triazoles. Compound 24, a potent inhibitor of cobalt-activated hMetAP2, also inhibits human and mouse endothelial cell growth. Using a mouse matrigel model, this reversible hMetAP2 inhibitor was also shown to inhibit angiogenesis in vivo.

Acute kidney injury, hyperbilirubinemia, and ischemic skin necrosis due to massive sulindac overdose.

Sulindac is a long-acting nonsteroidal anti-inflammatory drug (NSAID) widely used for the management of osteoarthritis, rheumatoid arthritis, ankylosing sponydlitis, and acute gouty arthritis. Reports of sulindac toxicity in the literature are rare. We report the case of a 22-year old male with a history of bipolar disorder who was brought to the emergency department after ingesting approximately 15 g of sulindac in a suicide attempt. He was found to have acute kidney injury and hyperbilirubinemia. Despite aggressive fluid resuscitation, his renal function progressively worsened requiring the initiation of hemodialysis. Ten days following ingestion of sulindac, he began to develop ischemic skin changes with a gangrenous appearance in his hands and feet. He continued to receive supportive treatment, and his acute kidney injury, hyperbillirubinemia, and ischemic skin necrosis eventually resolved. Clinicians should be aware of this long-acting NSAID and its ability to cause prolonged multisystem organ dysfunction.

Pegylated interferon induced myasthenia crisis--a case report.

Interferons (IFNs) have antiviral, antimitogenic, and immunostimulatory effects and are often used in the treatment of viral hepatitis and some neoplasms. Combination pegylated IFN-alpha and ribavirin therapy is currently recommended for the treatment of hepatitis C. Triple therapy, with the addition of a protease inhibitor, such as telaprevir or boceprevir, has recently become a mainstay of therapy for certain genotypes. There have also been reports outlining side effects associated with conventional IFN therapy and its immunostimulatory effects, which may cause autoimmune phenomena, including but not limited to Guillain-Barre syndrome, polymyositis, acute and chronic demyelinating polyneuropathy, and myasthenia gravis. Although a number of cases of interferon-induced myasthenia gravis have been reported, we present a case of interferon-induced myasthenia crisis that developed soon after retreatment of hepatitis C with combination interferon, ribavirin, and telaprevir.

Development of a high-throughput screen to detect inhibitors of TRPS1 sumoylation.

Small ubiquitin-like modifier (SUMO) belongs to the family of ubiquitin-like proteins (Ubls) that can be reversibly conjugated to target-specific lysines on substrate proteins. Although covalently sumoylated products are readily detectible in gel-based assays, there has been little progress toward the development of robust quantitative sumoylation assay formats for the evaluation of large compound libraries. In an effort to identify inhibitors of ubiquitin carrier protein 9 (Ubc9)-dependent sumoylation, a high-throughput fluorescence polarization assay was developed, which allows detection of Lys-1201 sumoylation, corresponding to the major site of functional sumoylation within the transcriptional repressor trichorhino-phalangeal syndrome type I protein (TRPS1). A minimal hexapeptide substrate peptide, TMR-VVK1201TEK, was used in this assay format to afford high-throughput screening of the GlaxoSmithKline diversity compound collection. A total of 728 hits were confirmed but no specific noncovalent inhibitors of Ubc9 dependent trans-sumoylation were found. However, several diaminopyrimidine compounds were identified as inhibitors in the assay with IC50 values of 12.5 µM. These were further characterized to be competent substrates which were subject to sumoylation by SUMO-Ubc9 and which were competitive with the sumoylation of the TRPS1 peptide substrates.