Chemically Driven Clearance of Amyloid Aggregates by Polyfunctionalized Furo[2,3-b:4,5-b']dipyridine-Chalcone Hybrids to Ameliorate Memory in an Alzheimer Mouse Model.

The aberrant assembly of amyloid-ß (Aß) is implicated in Alzheimer's disease (AD). Recent clinical outcomes of Aß-targeted immunotherapy reinforce the notion that clearing Aß burden is a potential therapeutic approach for AD. Herein, to develop drug candidates for chemically driven clearance of Aß aggregates, we synthesized 51 novel polyfunctionalized furo[2,3-b:4,5-b']dipyridine-chalcone hybrid compounds. After conducting two types of cell-free anti-Aß functional assays, Aß aggregation prevention and Aß aggregate clearance, we selected YIAD-0336, (E)-8-((1H-pyrrol-2-yl)methylene)-10-(4-chlorophenyl)-2,4-dimethyl-7,8-dihydropyrido[3',2':4,5]furo[3,2-b]quinolin-9(6H)-one, for further in vivo investigations. As YIAD-0336 exhibited a low blood-brain barrier penetration profile, it was injected along with aggregated Aß directly into the intracerebroventricular region of ICR mice and ameliorated spatial memory in Y-maze tests. Next, YIAD-0336 was orally administered to 5XFAD transgenic mice with intravenous injections of mannitol, and YIAD-0336 significantly removed Aß plaques from the brains of 5XFAD mice. Collectively, YIAD-0336 dissociated toxic aggregates in the mouse brain and hence alleviated cognitive deterioration. Our findings indicate that chemically driven clearance of Aß aggregates is a promising therapeutic approach for AD.

Design and discovery of new selective and potent VEGF receptor 2 tyrosine kinase inhibitors.

A series of novel substituted 4-anilinoquinazolines and their related compounds were designed and prepared by 3D modeling as potential inhibitors of VEGFR-2. Evaluation of VEGFR inhibitory activities suggested that compound I10 was a more potent (IC50 = 0.11 nM) VEGFR-2 inhibitor than most of the listed drugs. Kinase panel assays demonstrated that compound I10 was the selective VEGFR-2 inhibitor. The prediction of 3D modeling unveiled a unique binding mode of this lead compound to VEGFR-2. Compound I10 exhibited remarkable anti-angiogenesis and anti-proliferation in HUVEC at low nanomolar concentrations. PK studies indicated that the lead compound possessed adequate oral bioavailability in various species. In vivo subcutaneous tumor model demonstrated that oral administration of I10 demonstrated potent efficacy in inhibiting tumor growth and angiogenesis. All these results suggested compound I10 is a potential drug candidate for cancer treatment.

LC-MS/MS determination of HY072808, a novel candidate for treating atopic dermatitis, and its active metabolite: Application to a first-in-human pharmacokinetic study.

HY072808 is a novel phosphodiesterase 4 inhibitor currently under clinical development to treat atopic dermatitis. The first step is to address the pharmacokinetics and safety after topical administration of HY072808 ointments in healthy humans. In this study, we developed a highly sensitive liquid chromatography-tandem mass spectrometry method to determine plasma HY072808 and its active metabolite, ZZ24, in tiny amounts. The plasma samples were prepared using a simple liquid-liquid extraction method. Liquid chromatographic separation was achieved by gradient elution. The MS/MS quantification was performed in positive ion mode via multiple reaction monitoring. The method showed satisfactory linearity from 10 to 4,000 pg/ml for HY072808 and ZZ24. There was no significant interference from blank plasma. The method was validated for accuracy and precision, matrix effect and extraction recovery, dilution integrity, injection carryover and stability according to the related guidelines of the regulatory authorities. The HY072808 and ZZ24 concentrations in human plasma from a clinical trial were determined using this method. In conclusion, the validated method was robust and could be utilized to support the clinical development of HY072808.

Antifibrotic Agents for the Management of CKD: A Review.

Kidney fibrosis is a hallmark of chronic kidney disease (CKD) and a potential therapeutic target. However, there are conceptual and practical challenges to directly targeting kidney fibrosis. Whether fibrosis is mainly a cause or a consequence of CKD progression has been disputed. It is unclear whether specifically targeting fibrosis is feasible in clinical practice because most drugs that decrease fibrosis in preclinical models target additional and often multiple pathogenic pathways (eg, renin-angiotensin-aldosterone system blockade). Moreover, tools to assess whole-kidney fibrosis in routine clinical practice are lacking. Pirfenidone, a drug used for idiopathic pulmonary fibrosis, is undergoing a phase 2 trial for kidney fibrosis. Other drugs in use or being tested for idiopathic pulmonary fibrosis (eg, nintedanib, PRM-151, epigallocatechin gallate) are also potential candidates to treat kidney fibrosis. Novel therapeutic approaches may include antagomirs (eg, lademirsen) or drugs targeting interleukin 11 or NKD2 (WNT signaling pathway inhibitor). Reversing the dysfunctional tubular cell metabolism that leads to kidney fibrosis offers additional therapeutic opportunities. However, any future drug targeting fibrosis of the kidneys should demonstrate added benefit to a standard of care that combines renin-angiotensin system with mineralocorticoid receptor (eg, finerenone) blockade or with sodium/glucose cotransporter 2 inhibitors.

NX210c Peptide Promotes Glutamatergic Receptor-Mediated Synaptic Transmission and Signaling in the Mouse Central Nervous System.

NX210c is a disease-modifying dodecapeptide derived from the subcommissural organ-spondin that is under preclinical and clinical development for the treatment of neurological disorders. Here, using whole-cell patch-clamp recordings, we demonstrate that NX210c increased α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)- and GluN2A-containing N-methyl-D-aspartate receptor (GluN2A-NMDAR)-mediated excitatory postsynaptic currents in the brain. Accordingly, using extracellular field excitatory postsynaptic potential recordings, an enhancement of synaptic transmission was shown in the presence of NX210c in two different neuronal circuits. Furthermore, the modulation of synaptic transmission and GluN2A-NMDAR-driven signaling by NX210c restored memory in mice chronically treated with the NMDAR antagonist phencyclidine. Overall, by promoting glutamatergic receptor-related neurotransmission and signaling, NX210c represents an innovative therapeutic opportunity for patients suffering from CNS disorders, injuries, and states with crippling synaptic dysfunctions.

The Protective Effects of Hydrogen Sulfide New Donor Methyl S-(4-Fluorobenzyl)-N-(3,4,5-Trimethoxybenzoyl)-l-Cysteinate on the Ischemic Stroke.

In this paper, we report the design, synthesis and biological evaluation of a novel S-allyl-l-cysteine (SAC) and gallic acid conjugate S-(4-fluorobenzyl)-N-(3,4,5-trimethoxybenzoyl)-l-cysteinate (MTC). We evaluate the effects on ischemia-reperfusion-induced PC12 cells, primary neurons in neonatal rats, and cerebral ischemic neuronal damage in rats, and the results showed that MTC increased SOD, CAT, GPx activity and decreased LDH release. PI3K and p-AKT protein levels were significantly increased by activating PI3K/AKT pathway. Mitochondrial pro-apoptotic proteins Bax and Bim levels were reduced while anti-apoptotic protein Bcl-2 levels were increased. The levels of cleaved caspase-9 and cleaved caspase-3 were also reduced in the plasma. The endoplasmic reticulum stress (ERS) was decreased, which in turns the survival rate of nerve cells was increased, so that the ischemic injury of neurons was protected accordingly. MTC activated the MEK-ERK signaling pathway and promoted axonal regeneration in primary neurons of the neonatal rat. The pretreatment of MEK-ERK pathway inhibitor PD98059 and PI3K/AKT pathway inhibitor LY294002 partially attenuated the protective effect of MTC. Using a MCAO rat model indicated that MTC could reduce cerebral ischemia-reperfusion injury and decrease the expression of proinflammatory factors. The neuroprotective effect of MTC may be due to inhibition of the over-activation of the TREK-1 channel and reduction of the current density of the TREK1 channel. These results suggested that MTC has a protective effect on neuronal injury induced by ischemia reperfusion, so it may have the potential to become a new type of neuro-ischemic drug candidate.

Disease area and mode of action as criteria to assign a default occupational exposure limit.

In the early stages of drug research and development, there are only a few or no toxicological data available for newly synthesized small molecule drug candidates (DC). Calculation of the DC's occupational exposure limit (OEL) without toxicological data is not possible. Nevertheless, an OEL is needed to indicate the level of protection required to minimize risks for laboratory researchers and technicians. For this reason, simplified guidance is required to predict possible health hazards of DCs and their corresponding safe inhalation exposure levels. Here, we evaluated 860 drug substances (DS) with OELs calculated by Novartis and grouped the DSs by disease area (DA) and then their mode of action (MoA). 28% of the evaluated DSs (n = 242) had an OEL <10 µg/m3 and 72% (n = 618) had an OEL ≥10 µg/m3. Our evaluation confirms that in the absence of any compound-specific data, the default OEL of 10 µg/m3 is a reasonably safe exposure limit for small molecule DCs. Furthermore, our analysis suggests certain DAs and MoAs as valid criteria that may be integrated into a company's specific strategy for the assessment of data-poor compounds in order to identify DCs in an early stage of their development which require a default OEL <10 µg/m3.

Structure-based optimization of a PDZ-binding motif within a viral peptide stimulates neurite outgrowth.

Protection of neuronal homeostasis is a major goal in the management of neurodegenerative diseases. Microtubule-associated Ser/Thr kinase 2 (MAST2) inhibits neurite outgrowth, and its inhibition therefore represents a potential therapeutic strategy. We previously reported that a viral protein (G-protein from rabies virus) capable of interfering with protein-protein interactions between the PDZ domain of MAST2 and the C-terminal moieties of its cellular partners counteracts MAST2-mediated suppression of neurite outgrowth. Here, we designed peptides derived from the native viral protein to increase the affinity of these peptides for the MAST2-PDZ domain. Our strategy involved modifying the length and flexibility of the noninteracting sequence linking the two subsites anchoring the peptide to the PDZ domain. Three peptides, Neurovita1 (NV1), NV2, and NV3, were selected, and we found that they all had increased affinities for the MAST2-PDZ domain, with Kd values decreasing from 1300 to 60 nm, while target selectivity was maintained. A parallel biological assay evaluating neurite extension and branching in cell cultures revealed that the NV peptides gradually improved neural activity, with the efficacies of these peptides for stimulating neurite outgrowth mirroring their affinities for MAST2-PDZ. We also show that NVs can be delivered into the cytoplasm of neurons as a gene or peptide. In summary, our findings indicate that virus-derived peptides targeted to MAST2-PDZ stimulate neurite outgrowth in several neuron types, opening up promising avenues for potentially using NVs in the management of neurodegenerative diseases.

Veverimer: An Emerging Potential Treatment Option for Managing the Metabolic Acidosis of CKD.

Sodium bicarbonate is the mainstay treatment of the metabolic acidosis of chronic kidney disease but associated concerns center on administering sodium to patients with hypertension and sodium-retentive states. Veverimer (formerly referred to as TRC101), a drug candidate for which Tricida, Inc is seeking approval from the US Food and Drug Administration, is a novel nonabsorbable polymer that binds hydrogen cations and chloride anions in the gastrointestinal tract and then is excreted fecally, thereby increasing serum bicarbonate concentration without administering sodium. We examine the published evidence on the investigational use of veverimer in patients with chronic kidney disease and metabolic acidosis. We highlight the achieved increase in serum bicarbonate concentration without coadministering sodium, effects on physical functioning, and the safety record of the drug. We also scrutinize certain unanticipated findings: a lack of dose dependency in the increase in serum bicarbonate concentration observed and that despite the presumed large hydrogen chloride losses in feces, veverimer induces an isochloremic increase in serum bicarbonate concentration that is accompanied by a decrease in serum anion gap. We propose likely explanations for these puzzling findings and raise questions about veverimer's mode of action and its potential interaction with colonic bacterial flora. Additional work is required to fill these knowledge gaps that could have important clinical implications.

Potent Antibiotics Active against Multidrug-Resistant Gram-Negative Bacteria.

The emergence of multidrug-resistant (MDR) Gram-negative bacteria has become a global problem. Among MDR Gram-negative bacteria, carbapenem-resistant Enterobacteriaceae (CRE), MDR Pseudomonas aeruginosa, and MDR Acinetobacter baumannii have limited treatment options and present serious threats. Therefore, strong countermeasures must be taken against these bacteria immediately. Accordingly, the focus of this review is on recent advances in the development of promising antibacterial agents against MDR Gram-negative bacteria. These agents include novel tetracyclines, polymyxins, ß-lactams, ß-lactam/ß-lactamase inhibitors, aminoglycosides, and peptide mimetics that have been recently approved or have shown promising results in clinical and preclinical development. This review summarizes these potent antibiotics in terms of their development status, mode of action, spectra of activity, and structure-activity relationship.

Grignard Reagent Utilization Enables a Practical and Scalable Construction of 3-Substituted 5-Chloro-1,6-naphthyridin-4-one Derivatives.

A robust, practical, and scalable approach for the construction of 3-substituted 5-chloro-1,6-naphthyridin-4-one derivatives 13 via the addition of Grignard reagents to 4-amino-2-chloronicotinonitrile (15) was developed. Starting with various Grignard reagents, a wide range of 3-substituted 5-chloro-1,6-naphthyridin-4-one derivatives 13 were conveniently synthesized in moderate-to-good yields through addition-acidolysis-cyclocondensation. In addition, the robustness and applicability of this synthetic route was proven on a 100 g scale, which would enable convenient sample preparation in the preclinical development of 1,6-naphthyridin-4-one-based MET-targeting antitumor drug candidates.

Commentary: Why Pharmaceutical Scientists in Early Drug Discovery Are Critical for Influencing the Design and Selection of Optimal Drug Candidates.

This commentary reflects the collective view of pharmaceutical scientists from four different organizations with extensive experience in the field of drug discovery support. Herein, engaging discussion is presented on the current and future approaches for the selection of the most optimal and developable drug candidates. Over the past two decades, developability assessment programs have been implemented with the intention of improving physicochemical and metabolic properties. However, the complexity of both new drug targets and non-traditional drug candidates provides continuing challenges for developing formulations for optimal drug delivery. The need for more enabled technologies to deliver drug candidates has necessitated an even more active role for pharmaceutical scientists to influence many key molecular parameters during compound optimization and selection. This enhanced role begins at the early in vitro screening stages, where key learnings regarding the interplay of molecular structure and pharmaceutical property relationships can be derived. Performance of the drug candidates in formulations intended to support key in vivo studies provides important information on chemotype-formulation compatibility relationships. Structure modifications to support the selection of the solid form are also important to consider, and predictive in silico models are being rapidly developed in this area. Ultimately, the role of pharmaceutical scientists in drug discovery now extends beyond rapid solubility screening, early form assessment, and data delivery. This multidisciplinary role has evolved to include the practice of proactively taking part in the molecular design to better align solid form and formulation requirements to enhance developability potential.

Effects of Rubiadin isolated from Prismatomeris connata on anti-hepatitis B virus activity in vitro.

Prismatomeris connata was a kind of Rubiaceae plant for treatment of hepatitis, hepatic fibrosis and silicosis. Whereas, the effective components of Prismatomeris connata remains unexplored. The aim of this study was to investigate the inhibitory effects and mechanisms of Rubiadin isolated from Prismatomeris connata against HBV using HepG2.2.15 cells. The levels of hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), and hepatitis B core antigen (HBcAg) in the supernatants or cytoplasm were examined using by enzyme-linked immunosorbent assay. HBV DNA was qualified q-PCR. Rubiadin was isolated by silica gel column. The structure of the compound was elucidated by HPLC, FT-IR, 1 H-NMR, 13 C-NMR and identified as 1,3-Dihydroxy-2-methyl-9, 10-anthraquinone. Rubiadin significantly decreased HBeAg,HBcAg secretion level and inhibit HBV DNA replication. Rubiadin inhibits the proliferation of the cells and HBx protein expression in a dose-dependent manner. The intracellular calcium concentration was significantly reduced. These results demonstrated that Rubiadin could inhibit HepG2.2.15 cells proliferation, reduce the level of HBx expression, and intracellular free calcium, which might become a novel anti-HBV drug candidate.

Obaculactone protects against bleomycin-induced pulmonary fibrosis in mice.

Idiopathic pulmonary fibrosis is a progressive, degenerative and almost irreversible disease. There is hardly an effective cure for lung damage due to pulmonary fibrosis. The purpose of this study was to evaluate the role of obaculactone in an already-assessed model of idiopathic pulmonary fibrosis induced by bleomycin administration. Mice were subjected to intratracheal instillation of bleomycin, and obaculactone was given orally after bleomycin instillation daily for 23days. Treatment with obaculactone ameliorated body weight loss, lung histopathology abnormalities and pulmonary collagen deposition, with a decrease of the inflammatory cell number and the cytokine level in bronchoalveolar lavage fluid. Moreover, obaculactone inhibited the expression of icam1, vcam1, inos and cox2, and attenuated oxidative stress in bleomycin-treated lungs. Importantly, the production of collagen I and α-SMA in lung tissues as well as the levels of TGF-ß1, ALK5, p-Smad2 and p-Smad3 in lung homogenates was also reduced after obaculactone treatment. Finally, the TGF-ß1-induced epithelial-mesenchymal transition via Smad-dependent and Smad-independent pathways was reversed by obaculactone. Collectively, these data suggest that obaculactone may be a promising drug candidate for the treatment of idiopathic pulmonary fibrosis.

MH84: A Novel γ-Secretase Modulator/PPARγ Agonist--Improves Mitochondrial Dysfunction in a Cellular Model of Alzheimer's Disease.

Developing new therapeutic strategies for Alzheimer's disease (AD) is a current challenge. Approved drugs merely act symptomatically and delay the progression of the disease for a relatively short period of time. Here, we investigated the effectiveness of MH84 in a cellular HEK293APPwt model of AD, characterized by elevated beta amyloid protein levels (Aß1-42) and mitochondrial dysfunction. MH84 is a derivate of pirinixic acid belonging to a novel class of γ-secretase modulators, which combines γ-secretase modulation with activation of peroxisome proliferator-activator receptor gamma (PPARγ). The mitochondria modifying Dimebon, the γ-secretase blocker DAPT, and the PPARγ agonist pioglitazone were used as controls. MH84 protects against nitrosative stress, increased mitochondrial respiration, citrate synthase (CS) activity and protein levels of PGC1α indicating enhanced mitochondrial content at nano-molar concentrations. Concurrently, MH84 decreased protein levels of APP, Aß1-42, and C-terminal fragments at micro-molar concentrations. Both Dimebon and DAPT reduced cellular Aß1-42 levels. Dimebon improved mitochondrial functions and DAPT decreased mitochondrial membrane potential. Pioglitazone had no effects on APP processing and mitochondrial function. Our data emphasizes MH84 as possible novel therapeutic agent with mitochondria-based mode of action.

Amblyomin-X induces ER stress, mitochondrial dysfunction, and caspase activation in human melanoma and pancreatic tumor cell.

During the last two decades, new insights into proteasome function and its role in several human diseases made it a potential therapeutic target. In this context, Amblyomin-X is a Kunitz-type FXa inhibitor similar to endogenous tissue factor pathway inhibitor (TFPI) and is a novel proteasome inhibitor. Herein, we have demonstrated Amblyomin-X cytotoxicity to different tumor cells lines such as pancreatic (Panc1, AsPC1BxPC3) and melanoma (SK-MEL-5 and SK-MEL-28). Of note, Amblyomin-X was not cytotoxic to normal human fibroblast cells. In addition, Amblyomin-X promoted accumulation of ER stress markers (GRP78 and GADD153) in sensitive (SK-MEL-28) and bortezomib-resistant (Mia-PaCa-2) tumor cells. The intracellular calcium concentration [Ca(2+)] i was slightly modulated in human tumor cells (SK-MEL-28 and Mia-PaCa-2) after 24 h of Amblyomin-X treatment. Furthermore, Amblyomin-X induced mitochondrial dysfunction, cytochrome-c release, PARP cleavage, and activation of caspase cascade in both human tumor (SK-MEL-28 and Mia-PaCa-2) cells. These investigations might help in further understanding of the antitumor properties of Amblyomin-X.

Design and synthesis of a novel candidate compound NTI-007 targeting sodium taurocholate cotransporting polypeptide [NTCP]-APOA1-HBx-Beclin1-mediated autophagic pathway in HBV therapy.

Sodium taurocholate cotransporting polypeptide (NTCP) is a multiple transmembrane transporter predominantly expressed in the liver, functioning as a functional receptor for HBV. Through our continuous efforts to identify NTCP as a novel HBV target, we designed and synthesized a series of new compounds based on the structure of our previous compound NT-5. Molecular docking and MD simulation validated that a new compound named NTI-007 can tightly bind to NTCP, whose efficacy was also measured in vitro virological examination and cytotoxicity studies. Furthermore, autophagy was observed in NTI-007 incubated HepG2.2.15 cells, and results of q-PCR and Western blotting revealed that NTI-007 induced autophagy through NTCP-APOA1-HBx-Beclin1-mediated pathway. Taken together, considering crucial role of NTCP in HBV infection, NTCP-mediated autophagic pathway may provide a promising strategy of HBV therapy and given efficacy of NTI-007 triggering autophagy. Our study suggests pre-clinical potential of this compound as a novel anti-HBV drug candidate.

Preclinical evaluation of human secretoglobin 3A2 in mouse models of lung development and fibrosis.

Secretoglobin (SCGB) 3A2 is a member of the SCGB gene superfamily of small secreted proteins, predominantly expressed in lung airways. We hypothesize that human SCGB3A2 may exhibit anti-inflammatory, growth factor, and antifibrotic activities and be of clinical utility. Recombinant human SCGB3A2 was expressed, purified, and biochemically characterized as a first step to its development as a therapeutic agent in clinical settings. Human SCGB3A2, as well as mouse SCGB3A2, readily formed a dimer in solution and exhibited novel phospholipase A2 inhibitory activity. This is the first demonstration of any quantitative biochemical measurement for the evaluation of SCGB3A2 protein. In the mouse as an experimental animal, human SCGB3A2 exhibited growth factor activity by promoting embryonic lung development in both ex vivo and in vivo systems and antifibrotic activity in the bleomycin-induced lung fibrosis model. The results suggested that human SCGB3A2 can function as a growth factor and an antifibrotic agent in humans. When SCGB3A2 was administered to pregnant female mice through the tail vein, the protein was detected in the dam's serum and lung, as well as the placenta, amniotic fluids, and embryonic lungs at 10 min postadministration, suggesting that SCGB3A2 readily crosses the placenta. The results warrant further development of recombinant SCGB3A2 as a therapeutic agent in treating patients suffering from lung diseases or preterm infants with respiratory distress.

New advances in drug development for metabolic dysfunction-associated diseases and alcohol-associated liver disease.

Metabolic disorders are currently threatening public health worldwide. Discovering new targets and developing promising drugs will reduce the global metabolic-related disease burden. Metabolic disorders primarily consist of lipid and glucose metabolic disorders. Specifically, metabolic dysfunction-associated steatosis liver disease (MASLD) and alcohol-associated liver disease (ALD) are two representative lipid metabolism disorders, while diabetes mellitus is a typical glucose metabolism disorder. In this review, we aimed to summarize the new drug candidates with promising efficacy identified in clinical trials for these diseases. These drug candidates may provide alternatives for patients with metabolic disorders and advance the progress of drug discovery for the large disease burden.

Immunotherapy and drug sensitivity predictive roles of a novel prognostic model in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most significant causes of cancer-related deaths in the worldwide. Currently, predicting the survival of patients with HCC and developing treatment drugs still remain a significant challenge. In this study, we employed prognosis-related genes to develop and externally validate a predictive risk model. Furthermore, the correlation between signaling pathways, immune cell infiltration, immunotherapy response, drug sensitivity, and risk score was investigated using different algorithm platforms in HCC. Our results showed that 11 differentially expressed genes including UBE2C, PTTG1, TOP2A, SPP1, FCN3, SLC22A1, ADH4, CYP2C8, SLC10A1, F9, and FBP1 were identified as being related to prognosis, which were integrated to construct a prediction model. Our model could accurately predict patients' overall survival using both internal and external datasets. Moreover, a strong correlation was revealed between the signaling pathway, immune cell infiltration, immunotherapy response, and risk score. Importantly, a novel potential drug candidate for HCC treatment was discovered based on the risk score and also validated through ex vivo experiments. Our finds offer a novel perspective on prognosis prediction and drug exploration for cancer patients.