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PMM2-CDG, a disease caused by mutations in phosphomannomutase-2, is the most common congenital disorder of glycosylation. Yet, it still lacks a cure. Targeting phosphomannomutase-2 with pharmacological chaperones or inhibiting the phosphatase activity of phosphomannomutase-1 to enhance intracellular glucose-1,6-bisphosphate have been proposed as therapeutical approaches. We used Recombinant Bacterial Thermal Shift Assay to assess the binding of a substrate analog to phosphomannomutase-2 and the specific binding to phosphomannomutase-1 of an FDA-approved drug - clodronate. We also deepened the clodronate binding by enzyme activity assays and in silico docking. Our results confirmed the selective binding of clodronate to phosphomannomutase-1 and shed light on such binding. • PMM2-CDG is a congenital disorder of glycosylation caused by mutations in phosphomannomutase-2 (PMM2). It has no cure. • Alpha- glucose-1,6-bisphosphate is a PMM2 stabilizer and activator, hydrolysed by a phosphatase in vivo. • We evaluated two approaches to develop therapies: pharmacological chaperones to stabilize PMM2 or specific phosphatase inhibitors. • We deepened the effect of Clodronate. Clodronate is a selective inhibitor for the main phosphatase acting on glucose-1,6-bisphosphate. • Recombinant Bacterial Cellular Thermal Shift Assay can be helpful in fast and preliminary drug screening. [ABSTRACT FROM AUTHOR]

Entry into mitosis has been classically attributed to the activation of a cyclin B/Cdk1 amplification loop via a partial pool of this kinase becoming active at the end of G2 phase. However, how this initial pool is activated is still unknown. Here we discovered a new role of the recently identified PP2A-B55 inhibitor FAM122A in triggering mitotic entry. Accordingly, depletion of the orthologue of FAM122A in C. elegans prevents entry into mitosis in germline stem cells. Moreover, data from Xenopus egg extracts strongly suggest that FAM122A-dependent inhibition of PP2A-B55 could be the initial event promoting mitotic entry. Inhibition of this phosphatase allows subsequent phosphorylation of early mitotic substrates by cyclin A/Cdk, resulting in full cyclin B/Cdk1 and Greatwall (Gwl) kinase activation. Subsequent to Greatwall activation, Arpp19/ENSA become phosphorylated and now compete with FAM122A, promoting its dissociation from PP2A-B55 and taking over its phosphatase inhibition role until the end of mitosis. Synopsis: PP2A-B55 inhibition at the G2-M transition is essential for mitotic entry, but Gwl and cyclin B1 kinases activating the inhibitor Arpp19 are still inactive in late G2. This work reveals FAM122A as an additional phosphatase inhibitor acting prior to phospho-Arpp19. Inhibition of PP2A-B55 at late G2 is promoted by FAM122A, which does not require phosphorylation to bind this phosphatase target. FAM122A is essential for mitotic entry in vivo in C. elegans. FAM122A-dependent inhibition of PP2A-B55 triggers mitotic entry by permitting cyclin A/Cdk-dependent phosphorylation events and Gwl-dependent Arpp19 phosphorylation. Once phosphorylated, phospho-Arpp19 replaces FAM122A from PP2A-B55 and takes over inhibition of this phosphatase for the remainder of mitosis. Structural models indicate that phospho-S67-Arpp19 may interact with ions in the phosphatase catalytic subunit, thereby mediating tighter association that displaces FAM122A. The sequential inhibition of PP2A-B55 by FAM122A and Greatwall substrate Arpp19 is crucial to trigger cyclin B/Cdk1 activation and a correct mitosis. [ABSTRACT FROM AUTHOR]

In the current study, Azo-Thiohydantoins derivatives were synthesized and characterized by using various spectroscopic techniques including FTIR, 1H-NMR, 13C-NMR, elemental and HRMS analysis. The compounds were evaluated for alkaline phosphatase activity and it was observed that among all the synthesized compounds, derivative 7e exhibited substantial inhibitory activity (IC50 = 0.308 ± 0.065 µM), surpassing the standard inhibitor (L–Phenyl alanine, IC50 = 80.2 ± 1.1 µM). Along with this, these derivatives were comprehensively examined regarding the electronic properties and reactivity of the synthesized compounds using Density Functional Theory (DFT) calculations, where the results were found very promising and the synthesized compound were found stable. After that, SwissADME evaluations highlighted compounds for their favorable physicochemical properties, including solubility and drug-likeness. Molecular docking exhibited the strong binding affinities of 7f and 7e derivatives with intestinal alkaline phosphatase (IAP), further supported by Molecular Dynamics (MD) simulations. This comprehensive integration of experimental and computational approaches sheds the light on the potential therapeutic applications of the synthesized compounds. By providing a detailed investigation of these aspects, this research opens the avenues for the development of novel pharmacologically active compounds with diverse applications. [ABSTRACT FROM AUTHOR]

During chronic stress, persistent activation of cAMP-dependent protein kinase (PKA) occurs, which can contribute to protective or maladaptive changes in the heart. We sought to understand the effect of persistent PKA activation on NaV1.5 channel distribution and function in cardiomyocytes using adult rat ventricular myocytes as the main model. PKA activation with 8CPT-cAMP and okadaic acid (phosphatase inhibitor) caused an increase in Na+ current amplitude without altering the total NaV1.5 protein level, suggesting a redistribution of NaV1.5 to the myocytes' surface. Biotinylation experiments in HEK293 cells showed that inhibiting protein trafficking from intracellular compartments to the plasma membrane prevented the PKA-induced increase in cell surface NaV1.5. Additionally, PKA activation induced a time-dependent increase in microtubule plus-end binding protein 1 (EB1) and clustering of EB1 at myocytes' peripheral surface and intercalated discs (ICDs). This was accompanied by a decrease in stable interfibrillar microtubules but an increase in dynamic microtubules along the myocyte surface. Imaging and coimmunoprecipitation experiments revealed that NaV1.5 interacted with EB1 and β-tubulin, and both interactions were enhanced by PKA activation. We propose that persistent PKA activation promotes NaV1.5 trafficking to the peripheral surface of myocytes and ICDs by providing dynamic microtubule tracks and enhanced guidance by EB1. Our proposal is consistent with an increase in the correlative distribution of NaV1.5, EB1, and β-tubulin at these subcellular domains in PKA-activated myocytes. Our study suggests that persistent PKA activation, at least during the initial phase, can protect impulse propagation in a chronically stressed heart by increasing NaV1.5 at ICDs. [ABSTRACT FROM AUTHOR]

The advent and clinical success of immune checkpoint inhibitors Ipilimumab, Nivolumab and Pembrolizumab has had a seismic impact on our drug discovery focus and rationale. Novel extrinsic targets that enhance immune responses to cancer are actively being pursued, while tumor intrinsic targets that render cancer cells more sensitive to the immune system have joined traditional intrinsic targets (e.g. directly cytotoxic) in the drug discovery pipeline. The phosphatase PTPN2 (TC‐PTP) and its paralog PTPN1 (PTP‐1B) are negative regulators of several cytokine signaling pathways and T cell receptor (TCR) signaling. In a recent publication, Baumgartner et al. demonstrate the pre‐clinical efficacy of a first‐in‐class dual PTPN1/N2 active site inhibitor (ABBV‐CLS‐484/AC484) in cancer models. [ABSTRACT FROM AUTHOR]

Gain-of-function mutations in LRRK2, which encodes the leucine-rich repeat kinase 2 (LRRK2), are the most common genetic cause of late-onset Parkinson's disease. LRRK2 is recruited to membrane organelles and activated by Rab29, a Rab guanosine triphosphatase encoded in the PARK16 locus. We present cryo-electron microscopy structures of Rab29-LRRK2 complexes in three oligomeric states, providing key snapshots during LRRK2 recruitment and activation. Rab29 induces an unexpected tetrameric assembly of LRRK2, formed by two kinase-active central protomers and two kinase-inactive peripheral protomers. The central protomers resemble the active-like state trapped by the type I kinase inhibitor DNL201, a compound that underwent a phase 1 clinical trial. Our work reveals the structural mechanism of LRRK2 spatial regulation and provides insights into LRRK2 inhibitor design for Parkinson's disease treatment. [ABSTRACT FROM AUTHOR]

Deposition of hydroxyapatite (HA) or alkaline phosphate crystals on soft tissues causes the pathological calcification diseases comprising of end-stage osteoarthritis (OA), ankylosing spondylitis (AS), medial artery calcification and tumour calcification. The pathological calcification is symbolised by increased concentration of tissue non-specific alkaline phosphatase (TNAP). An efficient therapeutic strategy to eradicate these diseases is required, and for this the alkaline phosphatase inhibitors can play a potential role. In this context a series of novel quinolinyl iminothiazolines was synthesised and evaluated for alkaline phosphatase inhibition potential. All the compounds were subjected to DFT studies where N-benzamide quinolinyl iminothiazoline (6g), N-dichlorobenzamide quinolinyl iminothiazoline (6i) and N-nitrobenzamide quinolinyl iminothiazoline (6j) were found as the most reactive compounds. Then during the in-vitro testing, the compound N-benzamide quinolinyl iminothiazoline (6g) exhibited the maximum alkaline phosphatase inhibitory effect (IC50 = 0.337 ± 0.015 µM) as compared to other analogues and standard KH2PO4 (IC50 = 5.245 ± 0.477 µM). The results were supported by the molecular docking studies, molecular dynamics simulations and kinetic analysis which also revealed the inhibitory potential of compound N-benzamide quinolinyl iminothiazoline (6g) against alkaline phosphatase. This compound can be act as lead molecule for the synthesis of more effective inhibitors and can be suggested to test at the molecular level. [ABSTRACT FROM AUTHOR]

[1,8]-Naphthyridine derivatives have been reported to possess important biological activities and may serve as attractive pharmacophores in the drug discovery process. [1,8]-Naphthyridine derivatives (1a-1l) were evaluated for inhibitory potential for isozymes of carbonic anhydrase (CA) and alkaline phosphatase (ALP). CAs have been reported to carry out reversible hydration of CO2 into HCO3−, secretion of electrolytes, acid–base regulation, bone resorption, calcification, and biosynthetic reactions. Whereas ALPs hydrolyze monophosphate esters with the release of inorganic phosphate and play an important role in bone mineralization. Both enzymes have been found to be over-expressed and raised functional activities in patients suffering from rheumatoid arthritis. The discovery of dual inhibitors of these enzymes may provide a synergistic effect to cure bone disorders such as rheumatoid arthritis and ankylosing spondylitis. Among the test compounds, the most potent inhibitors for CA-II, CA-IX, and CA-XII were 1e, 1g, and 1a with IC50 values of 0.44 ± 0.19, 0.11 ± 0.03 and 0.32 ± 0.07 µM, respectively. [1,8]-Naphthyridine derivatives (1a–1l) were approximately 4 folds more potent than standard CA inhibitor acetazolamide. While in the case of ALPs, the most potent compounds for b-TNAP and c-IAP were 1b and 1e with IC50 values of 0.122 ± 0.06 and 0.107 ± 0.02 µM, respectively. Thus, synthesized derivatives proved to be 100 to 800 times more potent as compared to standard inhibitors of b-TNAP and c-IAP (Levamisole and L-phenyl alanine, respectively). In addition, selectivity and dual inhibition of [1,8]-Naphthyridine derivatives confer precedence over known inhibitors. Molecular docking and molecular simulation studies were also conducted in the present studies to define the type of interactions between potential inhibitors and enzyme active sites. [ABSTRACT FROM AUTHOR]

SUMMARY: Scutellaria barbata is a traditional Chinese herb medicine and a major source of bioactive clerodane diterpenoids. However, barely clerodanes have been isolated from the closely related S. baicalensis. Here we assembled a chromosome‐level genome of S. barbata and identified three class II clerodane diterpene synthases (SbarKPS1, SbarKPS2 and SbaiKPS1) from these two organisms. Using in vitro and in vivo assays, SbarKPS1 was characterized as a monofunctional (−)‐kolavenyl diphosphate synthases ((−)‐KPS), while SbarKPS2 and SbaiKPS1 produced major neo‐cleroda‐4(18),13E‐dienyl diphosphate with small amount of (−)‐KPP. SbarKPS1 and SbarKPS2 shared a high protein sequence identity and formed a tandem gene pair, indicating tandem duplication and sub‐functionalization probably led to the evolution of monofunctional (−)‐KPS in S. barbata. Additionally, SbarKPS1 and SbarKPS2 were primarily expressed in the leaves and flowers of S. barbata, which was consistent with the distribution of major clerodane diterpenoids scutebarbatine A and B. In contrast, SbaiKPS1 was barely expressed in any tissue of S. baicalensis. We further explored the downstream class I diTPS by functional characterizing of SbarKSL3 and SbarKSL4. Unfortunately, no dephosphorylated product was detected in the coupled assays with SbarKSL3/KSL4 and four class II diTPSs (SbarKPS1, SbarKPS2, SbarCPS2 and SbarCPS4) when a phosphatase inhibitor cocktail was included. Co‐expression of SbarKSL3/KSL4 with class II diTPSs in yeast cells did not increase the yield of the corresponding dephosphorylated products, either. Together, these findings elucidated the involvement of two class II diTPSs in clerodane biosynthesis in S. barbata, while the class I diTPS is likely not responsible for the subsequent dephosphorylation step. Significance Statement: This study reveals that the class II clerodane diTPS is one of the key factors contributing to the distinct clerodane diterpenoid profiles between S. barbata and S. baicalensis; and strongly indicates that class I diTPS is not involved in the clerodane diterpenoid biosynthesis in S. barbata. [ABSTRACT FROM AUTHOR]

Stilbenes accumulate in Scots pine heartwood where they have important roles in protecting wood from decaying fungi. They are also part of active defense responses, and their production is induced by different (a)biotic stressors. The specific transcriptional regulators as well as the enzyme responsible for activating the stilbene precursor cinnamate in the pathway are still unknown. UV-C radiation was the first discovered artificial stress activator of the pathway. Here, we describe a large-scale transcriptomic analysis of pine needles in response to UV-C and treatment with translational inhibitors, both activating the transcription of stilbene pathway genes. We used the data to identify putative candidates for the missing CoA ligase and for pathway regulators. We further showed that the pathway is transcriptionally activated by phosphatase inhibitor, ethylene and jasmonate treatments, as in grapevine, and that the stilbene synthase promoter retains its inducibility in some of the tested conditions in Arabidopsis, a species that normally does not synthesize stilbenes. Shared features between gymnosperm and angiosperm regulation and partially retained inducibility in Arabidopsis suggest that pathway regulation occurs not only via ancient stress-response pathway(s) but also via species-specific regulators. Understanding which genes control the biosynthesis of stilbenes in Scots pine aids breeding of more resistant trees. [ABSTRACT FROM AUTHOR]

Background: Glutamate, an excitatory neurotransmitter, plays a pivotal role in cellular phenomena in neurons, like synaptic plasticity and excitotoxicity. As the major glutamate receptors, N-methyl- D-aspartate receptors (NMDARs) undergo phosphorylation at Ser1303 on the GluN2B subunit upon glutamate binding. This effect results from the influx of calcium and subsequent activation of many known kinases that phosphorylate the receptor. However, the regulation of this phosphorylation at this site and the involved phosphatases have remained unknown, especially under excitotoxicity conditions induced by glutamate treatment. Objectives: This study attempts to investigate the regulation of phosphorylation at GluN2B-Ser1303 under excitotoxic conditions and identify the phosphatase responsible. Materials & Methods: Primary cortical neurons prepared from embryonic rat brains were treated with glutamate, thereby inducing excitotoxicity in vitro. Then, the phosphorylation status of GluN2B-Ser1303 was studied using Western blots in the presence of various phosphatase inhibitors. Finally, the interaction of phosphatase with GluN2B was studied using immunostaining and coimmunoprecipitation analysis. Results: The results show that under excitotoxic conditions, there is a reduction in the phosphorylation of GluN2B-Ser1303, and protein phosphatase 1 (PP1) was the phosphatase responsible. PPI was found to interact with the receptor. Conclusion: This study reports for the first time the regulation of phosphorylation at GluN2BSer1303 in vitro under excitotoxic conditions, which PP1 mediates. This site could be a potential drug target for designing novel compounds which could exacerbate excitotoxicity. [ABSTRACT FROM AUTHOR]

Helicobacter pylori is the most common cause of gastric ulcers and is associated with gastric cancer. The enzyme HppA of class C nonspecific acid phosphohydrolases (NSAPs) of H. pylori plays a crucial role in the electron transport chain. Herein, we report an in silico homology model of HppA consisting of a monomeric α + β model. A high throughput structure‐based virtual screening approach yielded potential inhibitors against HppA with higher binding energies. Further analyses of molecular interaction maps and protein–ligand fingerprints, followed by molecular mechanics‐generalized Born surface area (MM‐GBSA) end point binding energy calculations of docked complexes, resulted in the detection of top binders/ligands. Our investigations identified potential substrate‐competitive small molecule inhibitors of HppA, with admissible pharmacokinetic properties. These molecules may provide a starting point for developing novel therapeutic agents against H. pylori. [ABSTRACT FROM AUTHOR]

Cholinesterase inhibitors are promising drugs for the symptomatic treatment of Alzheimer's disease. In the current study, we explored the quantitative structure activity relationship (QSAR) of a series of Liquiritigenin derivatives recently assessed for their anti‐acetylcholinesterase activity. The multiple linear regression was applied to establish a QSAR model relating the biological activities of the studied compounds to their molecular descriptors. The QSAR model quality was evaluated by adopting Golbraikh and Tropsha's criteria. The obtained results highlight the fact that the developed model is perfectly valid (MSE=0.038; R2=0.789; R2adj=0.747; Q2CV=0.670; F=18.751) and exhibit high predictive power (R2test=0.760). Besides, Balaban Index (J), total energy (ET), dipole moment (μ) and electrophilicity index (ω) were identified to be the most relevant descriptors governing the anti‐acetylcholinesterase activity. By analyzing these molecular features, new Liquiritigenin derivatives with enhanced anti‐acetylcholinesterase activity were designed. Moreover, both molecular docking and molecular dynamics were performed to support the obtained results. In addition, the pharmacokinetics properties corresponding to the designed molecules were estimated. As a result, the compounds D10 and D13 were found to possess good pharmacokinetics properties and predicted to form stable complexes with the acetylcholinesterase protein, supporting their use as anti‐Alzheimer drug candidates. [ABSTRACT FROM AUTHOR]

The present study describes the facile synthesis and comprehensive characterization of new oxido and peroxidoniobium(V) complexes with biogenic ligands, maltol (malt) and deferiprone (def) in their co-ordination sphere, viz., [NbO(malt)3]2·9H2O (1), Na2[Nb(O2)3(malt)]·H2O (2) and Na2[Nb(O2)3(def)]·2H2O (3). The complexes were characterized using various analytical and spectroscopic techniques (FTIR, Raman, NMR, UV-visible, TGA, ICP-OES and elemental analysis). The charge neutral complex 1 was further characterized by single crystal XRD analysis, and the proposed structures of the peroxidoniobium (pNb) complexes 2 and 3 were validated by density functional theory (DFT) studies. A comparative investigation on the in vitro effect of the title compounds and a set of previously reported polymer-anchored peroxidoniobium complexes, [Nb(O2)3(sulfonate)2]3−-PSS [PSS = poly(sodium 4-styrene sulfonate)] (5), [Nb2(O2)6(carboxylate)2]4−-PA [PA = poly(sodium acrylate)] (6) and [Nb(O2)3(carboxylate)]2−-PMA [PMA = poly(sodium methacrylate)] (7), on the activity of the model enzyme wheat thylakoid acid phosphatase has revealed that each of the compounds is an effective inhibitor of the enzyme (IC50 values varying within the range 1–64 μM). The results of the detailed enzyme kinetic study demonstrated that the compounds induce their inhibitory effect via distinct pathways. The oxidoniobium complex 1 as well as polymer-anchored pNb complexes acted as classical non-competitive inhibitors of ACP, whereas the monomeric pNb complexes emerged as mixed inhibitors of the enzyme (Kii > Ki). Notably, the complexes serve as excellent recyclable catalysts for selective styrene epoxidation with H2O2, affording 99% styrene conversion, ≥98% epoxide selectivity and a high turnover number of 1740 under eco-friendly solventless conditions. [ABSTRACT FROM AUTHOR]

Protein Tyrosine Phosphatase 1B (PTP1B) is a protein that contributes to the development of diseases that affect millions of people worldwide. In the last five years, several studies have been carried out to develop a drug that is capable of inhibiting the functions of this protein that are related to chronic degenerative diseases and obesity. In this study, we used PTP1B as a therapeutic target to perform a molecular docking to identify compounds that specifically bind to the PTP1B human protein. After molecular docking from over 500,000 compounds, we selected the six with the highest binding score and evaluated their inhibitory effect in in vitro assays. The data showed that PT2 compound was the most potent with an IC50 value of 9 μM and a noncompetitive inhibition mechanism. According to molecular docking, this compound made specific interactions in the catalytic domain of PTP1B, that could be responsible for their inhibition capability. Furthermore, cytotoxic studies in MCF‐7 cells indicated that it could be safe for humans. Therefore, PT2 compound may be a promising new drug to attend the diseases where PTP1B has functions. [ABSTRACT FROM AUTHOR]

Aims Endothelial-to-mesenchymal transition (EndMT) is a fundamental process in vascular remodelling. However, the precise regulatory mechanism of vascular remodelling during neointima formation and the source of neointima cells are not entirely understood. Methods and results To investigate the origin of neointima cells and their relevance to vascular wall remodelling, we used an endothelial cell (EC)-specific lineage tracing system [VE-Cadherin (Cdh5)-BAC-CreERT2 mice] and carotid artery ligation model and showed evidence that resident ECs transdifferentiate into neointima cells with the expression of CD45. During the early stages of neointima formation, ECs transiently expressed CD45, a haematopoietic marker, accompanied by a host of EndMT markers, and CD31 and αSMA were prominently expressed in developing neointima. In vitro , CD45-positive EndMT was induced by stabilization of HIF1α with cobalt chloride or with a VHL inhibitor in human primary ECs, which mimicked the hypoxic condition of the ligated artery, and promoted the formation of an integrin α11-shank-associated RH domain-interacting protein (SHARPIN) complex. Notably, a CD45 phosphatase inhibitor disrupted this integrin α11-SHARPIN complex, thereby destabilizing cell–cell junctions. Deletion of Hif1α in ECs suppressed expression of CD45 and EndMT markers and ameliorated neointima formation. Conclusion These results suggest that the HIF-induced CD45 expression is normally required for the retention of an EC fate and cell–cell junctions, CD45-positive EndMT (termed as 'partial EndMT') contributes to neointima formation and vascular wall remodelling. [ABSTRACT FROM AUTHOR]

The tea plant (Camellia sinensis) belongs to the family Theaceae and contains many phytochemicals that are effective against various diseases, including neurodegenerative disorders. In this study, we aimed to characterize the phytochemicals present in the methanolic and n-hexane leaf extracts of C. sinensis using GC–MS, FTIR, and UV–visible analysis. We detected a total of 19 compounds of different chemical classes. We also performed molecular docking studies using the GC–MS detected phytochemicals, targeting acetylcholinesterase (AChE, PBD ID: 4BDT) and butyrylcholinesterase (BChE, PDB ID: 6QAB), which are responsible for the breakdown of the neurotransmitter acetylcholine (ACh). This breakdown leads to dementia and cognitive decline in Alzheimer's patients. The compounds Ergosta-7,22-dien-3-ol, (3.beta.,5.alpha.,22E)- and Benzene, 1,3-bis(1,1-dimethylethyl) showed better binding affinity against AChE, while dl-.alpha.-Tocopherol and Ergosta-7,22-dien-3-ol, (3.beta.,5.alpha.,22E)- showed better binding affinity against BChE. We determined the stability and rigidity of these best docked complexes through molecular dynamics simulation for a period of 100 ns. All complexes showed stability in terms of SASA, Rg, and hydrogen bonds, but some variations were found in the RMSD values. Our ADMET analysis revealed that all lead compounds are non-toxic. Therefore, these compounds could be potential inhibitors of AChE and BChE. [ABSTRACT FROM AUTHOR]

Clinically, early brain injury (EBI), which refers to the acute injuries to the whole brain in the phase of the first 72 h following subarachnoid hemorrhage (SAH), is intensely investigated to improve neurological and psychological function. Additionally, it will be meaningful to explore new therapeutic approaches for EBI treatment to improve the prognosis of patients with SAH. To investigate the underlying neuroprotection mechanism in vitro, the Protein tyrosine phosphatase 1B inhibitor (PTP1B-IN-1) was put in primary neurons induced by OxyHb to observe neuroapoptosis, neuroinflammation, and ER stress. Then, one hundred forty male mice were subjected to Experiment two and Experiment three. The mice in the SAH24h + PTP1B-IN-1 group were given an intraperitoneal injection of 5 mg/kg PTP1B-IN-1 30 min before anesthesia. SAH grade, neurological score, brain water content, Western blot, PCR, and Transmission Electron Microscopy (TEM) were performed to observe the underlying neuroprotection mechanism in vivo. Overall, this study suggests that PTP1B-IN-1 could ameliorate neuroapoptosis, neuroinflammation, and ER stress in vitro and in vivo by regulating the IRS-2/AKT signaling pathway, suggesting that PTP1B-IN-1 may be a candidate drug for the treatment of early brain injury after SAH. [ABSTRACT FROM AUTHOR]

The pursuit of step- and atom-economy in natural product and complex molecule syntheses continuously inspires the development of synthetic methodologies. In this context, to enable efficient synthesis of (E , E)-dienes as common structural subunits in natural products, our lab has established robust protocols based on modified Negishi cross-couplings and evolved them to more concise titanium-mediated alkyne–alkyne reductive coupling. In this review, we summarize the natural product synthesis driven methodology development and their applications in the total synthesis of complex molecules, focusing on the studies from our laboratory. 1 Introduction 2 Transition-Metal-Catalyzed Cross-Coupling in Natural Product Synthesis 2.1 Synthesis of Branched Trisubstituted Conjugated Dienes by Negishi Coupling 2.2 Stereo- and Regiocontrolled Synthesis of Branched Trisubstituted Conjugated Dienes by Modified Negishi Coupling 2.3 Enantioselective Total Synthesis of Reveromycin B by Drouet & Theodorakis 2.4 Enantioselective Synthesis of the Protein Phosphatase Inhibitor (–)-Motuporin by Hu & Panek 2.5 Total Synthesis of (–)-Callystatin A by Langille & Panek 2.6 Total Synthesis of Brevisamide by Lee & Panek 3 Titanium Alkoxide-Mediated Reductive Coupling in Natural Product Synthesis 3.1 Titanium Alkoxide-Mediated Alkyne–Alkyne Reductive Coupling 3.2 Total Synthesis of Callystatin A by Reichard & Micalizio 3.3 Total Synthesis of (–)-Virginiamycin M2 by Wu & Panek 3.4 Total Synthesis of Nuclear Factor of Activated T-Cells-68 (NFAT-68) by Cai & Panek 3.5 Titanium Alkoxide-Based Regioselective Alkyne–Alkyne Reductive Coupling Mediated by in situ Generated Arylamidate 4 Summary [ABSTRACT FROM AUTHOR]

A new class of indolotacrine hybrids including cyclopenta- and cyclohexa-indolotacrine derivatives was designed, synthesized, and assessed as acetylcholinesterase inhibitors (AChEIs). Some of the designed derivatives indicated a good inhibitory effect against acetylcholinesterase (AChE). Among them, cyclopenta-indolotacrine hybrids showed a slightly better anti-AChE activity than cyclohexa-indolotacrine hybrids. Compound 5-amino-4-(4-chlorophenyl)-2-(1H-indol-3-yl)-4,6,7,8-tetrahydrocyclopenta[b]pyrano[3,2-e]pyridine-3-carbonitrile (8g) including 4-chlorophenyl and cyclopentane ring showed the best AChE inhibitory activity with IC50 value of 0.4 µM. The kinetic study indicated that compound 8g acted as a competitive inhibitor. Based on molecular docking results, it occupied both the catalytic anionic site (CAS) and peripheral anionic site (PAS) of AChE. Using a neuroprotective assay against H2O2-induced cell death in PC12 neurons, only compound 8b with 4-methoxyphenyl moiety and cyclopentane ring illustrated significant protection (P < 0.0001) at a concentration of 100 μM compared to quercetin at a concentration of 10 μM (P < 0.0001). In silico ADME studies estimated good drug-likeness for the designed compounds. As a result, these indolotacrine hybrids can be a very encouraging AChE inhibitor to treat Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Lipid interaction with α-synuclein (αSyn) has been long implicated in the pathogenesis of Parkinson's disease (PD). However, it has not been fully determined which lipids are involved in the initiation of αSyn aggregation in PD. Here exploiting genetic understanding associating the loss-of-function mutation in Synaptojanin 1 (SYNJ1), a phosphoinositide phosphatase, with familial PD and analysis of postmortem PD brains, we identified a novel lipid molecule involved in the toxic conversion of αSyn and its relation to PD. We first established a SYNJ1 knockout cell model and found SYNJ1 depletion increases the accumulation of pathological αSyn. Lipidomic analysis revealed SYNJ1 depletion elevates the level of its substrate phosphatidylinositol-3,4,5-trisphosphate (PIP3). We then employed Caenorhabditis elegans model to examine the effect of SYNJ1 defect on the neurotoxicity of αSyn. Mutations in SYNJ1 accelerated the accumulation of αSyn aggregation and induced locomotory defects in the nematodes. These results indicate that functional loss of SYNJ1 promotes the pathological aggregation of αSyn via the dysregulation of its substrate PIP3, leading to the aggravation of αSyn-mediated neurodegeneration. Treatment of cultured cell line and primary neurons with PIP3 itself or with PIP3 phosphatase inhibitor resulted in intracellular formation of αSyn inclusions. Indeed, in vitro protein–lipid overlay assay validated that phosphoinositides, especially PIP3, strongly interact with αSyn. Furthermore, the aggregation assay revealed that PIP3 not only accelerates the fibrillation of αSyn, but also induces the formation of fibrils sharing conformational and biochemical characteristics similar to the fibrils amplified from the brains of PD patients. Notably, the immunohistochemical and lipidomic analyses on postmortem brain of patients with sporadic PD showed increased PIP3 level and its colocalization with αSyn. Taken together, PIP3 dysregulation promotes the pathological aggregation of αSyn and increases the risk of developing PD, and PIP3 represents a potent target for intervention in PD. [ABSTRACT FROM AUTHOR]

G protein-coupled receptors (GPCRs) are important signal transducers that are phosphorylated upon activation at intracellular serine and threonine residues. Although antibodies that specifically recognize the phosphorylation state of GPCRs have been available for many years, efficient immunolocalization of phosphorylated receptors in their tissues of origin has not been possible. Here, we show that phosphorylation of receptors is highly unstable during routine immunohistochemical procedures, requiring the use of appropriate phosphatase inhibitors particular during tissue perfusion, post-fixation, and cryoprotection but not during immunostaining of tissue sections. We provide proof of concept using phosphorylation state-specific μ-opioid receptor (MOP) and cannabinoid receptor 1 (CB1) antibodies. Indeed, three of four well-characterized phosphosite-specific MOP antibodies, including pS375-MOP, pT376-MOP, and pT379-MOP, showed robust neuronal immunostaining in brain and spinal cord sections of opioid-treated mice only after inclusion of phosphatase inhibitors. We then extended this approach to the CB1 receptor and demonstrated that one of three newly-generated phosphosite-specific CB1 antibodies, namely pS425-CB1, showed striking staining of fibers and varicosities in brain slices from cannabinoid-treated mice. Although subsequent experiments showed that phospho-CB1 immunostaining was less sensitive to phosphatases, we conclude that the use of phosphatase inhibitors should always be considered in the development of immunohistochemical procedures for new phosphosite-specific GPCR antibodies. In summary, we anticipate that this improved protocol will facilitate the widespread use of phosphorylation state-specific antibodies to monitor the activation of endogenous GPCRs under physiological and pharmacological conditions. Our approach may also prove useful to confirm target engagement of GPCR drug candidates in native tissues. Phosphorylation of receptors is shown to be unstable during routine immunohistochemical procedures in mice thus phosphatase inhibitors should be used alongside phosphosite-specific GPCR antibodies. [ABSTRACT FROM AUTHOR]

Purpose: One of the promising chemical groups for the development of new antihypertensive medicines, the action of which is associated with the inhibition of phosphodiesterase III (PDE3) activity, are phosphorylated oxazole derivatives (OVPs). This study aimed to prove experimentally the presence of the OVPs antihypertensive effect associated with decreasing of PDE activity and to justify its molecular mechanism. Methods: An experimental study of the effect of OVPs on phosphodiesterase activity was performed on Wistar rats. Determination of PDE activity was performed by fluorimetric method using umbelliferon in blood serum and organs. The docking method was used to investigate the potential molecular mechanisms of the antihypertensive action of OVPs with PDE3. Results: The introduction of OVP-1 50 mg/kg, as a leader compound, led to the restoration of PDE activity in the aorta, heart and serum of rats with hypertension to the values observed in the intact group. This may indicate the possibility of the development of vasodilating action of OVPs by the influence of the latter on the increase in cGMP synthesis due to inhibition of PDE activity. The calculated results of molecular docking of ligands OVPs to the active site of PDE3 showed that all test compounds have a common type of complexation due to phosphonate groups, piperidine rings, side and terminal phenyl and methylphenyl groups. Conclusion: The analysis of the obtained results both in vivo and in silico showed that phosphorylated oxazole derivatives represent a new platform for further studies as phosphodiesterase III inhibitors with antihypertensive activity. [ABSTRACT FROM AUTHOR]

Dual inhibitors of protein phosphotyrosine phosphatase 1B (PTP1B)/T-cell protein phosphotyrosine phosphatase (TC-PTP) based on the 3-(hydroxymethyl)-4-oxo-1,4-dihydrocinnoline scaffold have been identified. Their dual affinity to both enzymes has been thoroughly corroborated by in silico modeling experiments. The compounds have been profiled in vivo for their effects on body weight and food intake in obese rats. Likewise, the effects of the compounds on glucose tolerance, insulin resistance, as well as insulin and leptin levels, have been evaluated. In addition, the effects on PTP1B, TC-PTP, and Src homology region 2 domain-containing phosphatase-1 (SHP1), as well as the insulin and leptin receptors gene expressions, have been assessed. In obese male Wistar rats, a five-day administration of all studied compounds led to a decrease in body weight and food intake, improved glucose tolerance, attenuated hyperinsulinemia, hyperleptinemia and insulin resistance, and also compensatory increased expression of the PTP1B and TC-PTP genes in the liver. The highest activity was demonstrated by 6-Chloro-3-(hydroxymethyl)cinnolin-4(1H)-one (compound 3) and 6-Bromo-3-(hydroxymethyl)cinnolin-4(1H)-one (compound 4) with mixed PTP1B/TC-PTP inhibitory activity. Taken together, these data shed light on the pharmacological implications of PTP1B/TC-PTP dual inhibition, and on the promise of using mixed PTP1B/TC-PTP inhibitors to correct metabolic disorders. [ABSTRACT FROM AUTHOR]

STS1 and STS2, as the protein phosphatases that dephosphorylate FLT3 and cKIT, negatively regulate the self-renewal and differentiation of hematopoietic stem and progenitor cells (HSPCs). To obtain the small molecule inhibitors of STS1/STS2 phosphatase activity used to expand HSPCs both in vitro and in vivo, we establish an in vitro phosphatase assay using the recombinant proteins of the STS1/STS2 histidine phosphatase (HP) domain, by which we screened out baicalein (BC) as one of the effective inhibitors targeting STS1 and STS2. Then, we further demonstrate the direct binding of BC with STS1/STS2 using molecular docking and capillary electrophoresis and verify that BC can restore the phosphorylation of FLT3 and cKIT from STS1/STS2 inhibition. In a short-term in vitro culture, BC promotes profound expansion and enhances the colony-forming capacity of both human and mouse HSPCs along with the elevation of phospho-FLT3 and phospho-cKIT levels. Likewise, in vivo administration with BC significantly increases the proportions of short-term hematopoietic stem cells (ST-HSCs), multipotent progenitors (MPPs) and especially long-term HSCs (LT-HSCs) in healthy mouse bone marrow and increases the numbers of colony-forming units (CFU) formed by HSPCs as well. More importantly, pre-administration of BC significantly enhances the survival of mice with lethal 5-fluorouracil (5-FU) injection due to the alleviation of 5-FU-induced myelosuppression, as evidenced by the recovery of bone marrow histologic injury, the increased proportions of LT-HSCs, ST-HSCs and MPPs, and enhanced colony-forming capacity. Collectively, our study not only suggests BC as one of the small molecule candidates to stimulate HSPC expansion both in vitro and in vivo when needed in either physiologic or pathologic conditions, but also supports STS1/STS2 as potential therapeutic drug targets for HSPC expansion and hematopoietic injury recovery. [ABSTRACT FROM AUTHOR]

Cantharidin and its analogs are potent serine/threonine protein phosphatase inhibitors with rare reports on inhibiting expression of Hepatitis B virus (HBV) DNA. Five imide cantharidin derivatives were synthesized, and their properties were studied. The inhibition efficiency was determined, and preliminary studies on the structure-activity relationships were conducted. The results indicated that the compounds characterized by low Log P values and the cantharidin moieties containing nitrogen exhibited low cytotoxicity and helped inhibit the expression of HBV DNA. Compound 2 and the non-cytotoxic compound 3 significantly inhibited the expression of HBV DNA. The IC50 values recorded for both compounds were 2.0±1.2 and 19.2±2.0 nM, respectively. [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver disease (NAFLD) is one of the common metabolic diseases characterized by hepatic lipid accumulation. Insulin resistance and microcirculation dysfunction are strongly associated with NAFLD. CX08005, an inhibitor of PTP1B with the IC50 of 0.75 ± 0.07 μM, has been proven to directly enhance insulin sensitivity. The present study aimed to investigate the effects of CX08005 on hepatic lipid accumulation and microcirculation dysfunction in both KKAy mice and diet-induced obesity (DIO) mice. Hepatic lipid accumulation was evaluated by hepatic triglyceride determination and B-ultrasound analysis in KKAy mice. Insulin sensitivity and blood lipids were assessed by insulin tolerance test (ITT) and triglyceride (TG)/total cholesterol (TC) contents, respectively. In addition, the hepatic microcirculation was examined in DIO mice by in vivo microscopy. The results showed that CX08005 intervention significantly reduced the TG and echo-intensity attenuation coefficient in the livers of KKAy mice. Furthermore, we found that CX08005 treatment significantly enhanced insulin sensitivity, and decreased plasma TG and/or TC contents in KKAy and DIO mice, respectively. In addition, CX08005 treatment ameliorated hepatic microcirculation dysfunction in DIO mice, as evidenced by increased RBCs velocity and shear rate of the blood flow in central veins and in the interlobular veins, as well as enhanced rate of perfused hepatic sinusoids in central vein area. Additionally, CX08005 administration decreased the adhered leukocytes both in the center veins and in the hepatic sinusoids area. Taken together, CX08005 exhibited beneficial effects on hepatic lipid accumulation and microcirculation dysfunction associated with NAFLD, which was involved with modulating insulin sensitivity and leukocyte recruitment, as well as restoration of normal microcirculatory blood flow. [ABSTRACT FROM AUTHOR]

Male fertility relies on the ability of spermatozoa to fertilize the egg in the female reproductive tract (FRT). Spermatozoa acquire activated motility during epididymal maturation; however, to be capable of fertilization, they must achieve hyperactivated motility in the FRT. Extensive research found that three protein phosphatases (PPs) are crucial to sperm motility regulation, the sperm-specific protein phosphatase type 1 (PP1) isoform gamma 2 (PP1γ2), protein phosphatase type 2A (PP2A) and protein phosphatase type 2B (PP2B). Studies have reported that PP activity decreases during epididymal maturation, whereas protein kinase activity increases, which appears to be a requirement for motility acquisition. An interplay between these PPs has been extensively investigated; however, many specific interactions and some inconsistencies remain to be elucidated. The study of PPs significantly advanced following the identification of naturally occurring toxins, including calyculin A, okadaic acid, cyclosporin, endothall and deltamethrin, which are powerful and specific PP inhibitors. This review aims to overview the protein phosphorylation-dependent biochemical pathways underlying sperm motility acquisition and hyperactivation, followed by a discussion of the PP inhibitors that allowed advances in the current knowledge of these pathways. Since male infertility cases still attain alarming numbers, additional research on the topic is required, particularly using other PP inhibitors. [ABSTRACT FROM AUTHOR]

A series of novel triazoloquinolinone and imidazoquinazolinone derivatives were designed and synthesised, and their biological activities against SHP2 protein and melanoma A357 cell line were evaluated in vitro. The results show that some target compounds have moderate to excellent inhibitory activity on SHP2 protein and melanoma A357 cell line. Structure-activity relationships (SARs) showed that both imidazoquinazolinone and triazoloquinazolinone derivatives have good SHP2 protein kinase and melanoma cell line A357 inhibitory activity. The results of molecular docking also showed that the cores of imidazoquinazolinone and triazoloquinazolinone have a certain affinity for SHP2 protein at the same time. Compared with SHP244, the target compounds have quite good liver microsomal stability and has more drug potential. The most promising compound B1 has a strong inhibitory effect on the melanoma cell line A357 at 100 µM (76.15% inhibition). [ABSTRACT FROM AUTHOR]

Objective: The current study evaluates the effect of metformin (MET) and /or alpha lipoic acid (ALA) on hypothyroidism and its adverse effects on the cardiac, renal, and, hepatic functions in rats. Materials and methods: Rats were divided into five groups: control, rat model of hypothyroidism induced by propylthiouracil (PTU), rat model of hypothyroidism treated with MET, rat model of hypothyroidism treated with ALA, and rat model of hypothyroidism treated with MET and ALA. At the end of the experiment, body weight gain was determined and the blood samples were collected from orbital plexus to measure the serum levels of thyroxine (T4), triiodothyronine (T3) and thyroid stimulating hormone (TSH) by ELISA, glucose level, the activities of lactate dehydrogenase (LDH), creatine kinase MB (CK-MB), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP), and the levels of urea and creatinine spectrophotometrically. Results: Rat model of hypothyroidism revealed a significant decrease in T4 (p < 0.001) and T3 (p < 0.001) and a significant increase in TSH (p < 0.005). This was accompanied by a significant decrease in the body weight gain (p < 0.025) and a significant increase in LDH (p < 0.001), CK-MB (p < 0.001) AST (p < 0.01), ALT (p < 0.016), ALP (p < 0.001), glucose (p < 0.001), urea (p < 0.001) and creatinine (p < 0.001). MET restored T4, T3 and TSH to control values. Treatment with ALA restored T3 and TSH levels. Treatment with Met and /or ALA reduced the levels of glucose, urea and creatinine and the activities of LDH, CK-MB, AST, ALT, and ALP to control-like values. Only ALA improved the reduced body weight gain induced by hypothyroidism. Conclusion: The present findings indicate the ameliorative effects of MET and /or ALA on hypothyroidism and its adverse effects on cardiac, renal and hepatic functions. [ABSTRACT FROM AUTHOR]

Salvia miltiorrhiza Bge is a medicinal plant (Chinese name "Danshen") widely used for the treatment of hyperglycemia in traditional Chinese medicine. Protein tyrosine phosphatase 1B (PTP1B) has been recognized as a potential target for insulin sensitizing for the treatment of diabetes. In this work, PTP1B was displayed at the surface of E. coli cells (EC-PTP1B) to be used as a bait for fishing of the enzyme's inhibitors present in the aqueous extract of S. miltiorrhiza. Salvianolic acid B, a polyphenolic compound, was fished out by EC-PTP1B, which was found to inhibit PTP1B with an IC50 value of 23.35 µM. The inhibitory mechanism of salvianolic acid B was further investigated by enzyme kinetic experiments and molecular docking, indicating salvianolic acid B was a non-competitive inhibitor for PTP1B (with Ki and Kis values of 31.71 µM and 20.08 µM, respectively) and its binding energy was −7.89 kcal/mol. It is interesting that in the comparative work using a traditional ligand fishing bait of PTP1B-immobilized magnetic nanoparticles (MNPs-PTP1B), no ligands were extracted at all. This study not only discovered a new PTP1B inhibitor from S. miltiorrhiza which is significant to understand the chemical basis for the hypoglycemic activity of this plant, but also indicated the effectiveness of cell display-based ligand fishing in screening of active compounds from complex herbal extracts. [ABSTRACT FROM AUTHOR]

To develop new alkaline phosphatase inhibitors (ALP), a series of pyrazolo-oxothiazolidine derivatives were synthesized and biologically assessed, and the results showed that all of the synthesized compounds significantly inhibited ALP. Specifically, compound 7g displayed the strongest inhibitory activity (IC50 = 0.045 ± 0.004 μM), which is 116-fold more active than monopotassium phosphate (IC50 = 5.242 ± 0.472 μM) as a standard reference. The most potent compound among the series (7g) was checked for its mode of binding with the enzyme and shown as non-competitively binding with the target enzyme. The antioxidant activity of these compounds was examined to investigate the radical scavenging effect. Moreover, the MTT assay method was performed to evaluate their toxic effects on the viability of MG-63 human osteosarcoma cells, and all compounds have no toxic effect on the cells at 4 μM. Computational research was also conducted to examine the binding affinity of the ligands with alkaline phosphatase, and the results revealed that all compounds showed good binding energy values within the active site of the target. Therefore, these novel pyrazolo-oxothiazolidine derivatives might be employed as promising pharmacophores for potent and selective alkaline phosphatase inhibitors. [ABSTRACT FROM AUTHOR]

Discovery of protein‐binding fragments for precisely defined binding sites is an unmet challenge to date. Herein, formylglycine is investigated as a molecular probe for the sensitive detection of fragments binding to a spatially defined protein site. Formylglycine peptide 3 was derived from a phosphotyrosine‐containing peptide substrate of protein tyrosine phosphatase PTP1B by replacing the phosphorylated amino acid with the reactive electrophile. Fragment ligation with formylglycine occurred in situ in aqueous physiological buffer. Structures and kinetics were validated by NMR spectroscopy. Screening and hit validation revealed fluorinated and non‐fluorinated hit fragments being able to replace the native phosphotyrosine residue. The formylglycine probe identified low‐affinity fragments with high spatial resolution as substantiated by molecular modelling. The best fragment hit, 4‐amino‐phenyl‐acetic acid, was converted into a cellularly active, nanomolar inhibitor of the protein tyrosine phosphatase SHP2. [ABSTRACT FROM AUTHOR]

The current study focused on the laboratory approach in conjunction with computational methods for the synthesis and bioactivity assessment of unique 2-tetradecanoylimino-3-aryl-4-methyl-1,3-thiazolines (2a–2k). Processes included cyclizing 1-aroyl-3-arylthioureas with propan-2-one in the presence of trimethylamine and bromine. By using spectroscopic techniques and elemental analyses, structures were elucidated. To assess the electronic properties, density functional theory (DFT) calculations were made, while binding interactions of synthesized derivatives were studied by the molecular docking tool. Promising results were found during the evaluation of bioactivity of synthesized compounds against alkaline phosphatase. The drug likeliness score, an indicator used for any chemical entity posing as a drug, was within acceptable limits. The data suggested that most of the derivatives were potent inhibitors of alkaline phosphatase, which in turn may act as lead molecules to synthesize derivatives having desired pharmacological profiles for the treatment of specific diseases associated with abnormal levels of ALPs. [ABSTRACT FROM AUTHOR]

Small molecules with nitrogen-containing scaffolds have gained much attention due to their biological importance in the development of new anticancer agents. The present paper reports the synthesis of a library of new dihydropyridine and pyridine analogs with diverse pharmacophores. All compounds were tested against the human tissue nonspecific alkaline phosphatase (h-TNAP) enzyme. Most of the compounds showed excellent enzyme inhibition against h-TNAP, having IC50 values ranging from 0.49 ± 0.025 to 8.8 ± 0.53 µM, which is multi-fold higher than that of the standard inhibitor (levamisole = 22.65 ± 1.60 µM) of the h-TNAP enzyme. Furthermore, an MTT assay was carried out to evaluate cytotoxicity against the HeLa and MCF-7 cancer cell lines. Among the analogs, the most potent dihydropyridine-based compound 4d was selected to investigate pro-apoptotic behavior. The further analysis demonstrated that compound 4d played a significant role in inducing apoptosis through multiple mechanisms, including overproduction of reactive oxygen species, mitochondrial dysfunction, DNA damaging, and arrest of the cell cycle at the G1 phase by inhibiting CDK4/6. The apoptosis-inducing effect of compound 4d was studied through staining agents, microscopic, and flow cytometry techniques. Detailed structure–activity relationship (SAR) and molecular docking studies were carried out to identify the core structural features responsible for inhibiting the enzymatic activity of the h-TNAP enzyme. Moreover, fluorescence emission studies corroborated the binding interaction of compound 4d with DNA through a fluorescence titration experiment. [ABSTRACT FROM AUTHOR]

A 30-day feeding trial was designed to investigate the physical properties of chitosan-coated microdiet (CCD) and the effect of CCD on survival, growth performance, activities of digestive enzymes, intestinal development, antioxidant capacity, and inflammatory response of large yellow croaker larvae (initial weight: 3.81 ± 0.20 mg). Four isonitrogenous (50% crude protein) and isolipidic (20% crude lipid) microdiets were prepared with different concentrations of chitosan wall material by spray drying method (0.00%, 0.30%, 0.60%, and 0.90%, weight (chitosan) : volume (acetic acid)). Results showed that the lipid encapsulation efficiency (control: 60.52%, Diet1: 84.63%, Diet2: 88.06%, Diet3: 88.65%) and nitrogen retention efficiency (control: 63.76%, Diet1: 76.14%, Diet2: 79.52%, Diet3: 84.68%) correlated positively with the concentration of wall material (P < 0.05). Furthermore, the loss rate of CCD was significantly lower than the uncoated diet. Larvae fed the diet with 0.60% CCD had significantly higher specific growth rate (13.52 and 9.95%/day) and survival rate (14.73 and 12.58%) compared to the control group (P < 0.05). Larvae fed the diet with 0.30% CCD had significantly higher trypsin activity in pancreatic segments than the control group (4.47 and 3.05 U/mg protein) (P < 0.05). Larvae fed the diet with 0.60% CCD had significantly higher activity of leucine aminopeptidase (7.29 and 4.77 mU/mg protein) and alkaline phosphatase (83.37 and 46.09 U/mg protein) in the brush border membrane than those of the control group (P < 0.05). The intestinal epithelial proliferation- and differentiation-related factors (zo-1, zo-2, and pcna) in larvae fed the diet with 0.30% CCD had higher expression than those of the control group (P < 0.05). When the concentration of wall material reached 0.90%, the larvae had significantly higher superoxide dismutase activity than that of the control group (27.27 and 13.72 U/mg protein) (P < 0.05). Meanwhile, malondialdehyde contents were significantly lower in larvae fed the diet with 0.90% CCD than that of the control group (8.79 and 6.79 nmol/mg protein) (P < 0.05). 0.30%~0.60% CCD significantly increased the activity of total nitric oxide synthase (2.31, 2.60, and 2.05 mU/mg protein) and inducible nitric oxide synthase (1.91, 2.01, and 1.63 mU/mg protein) and had significantly higher transcriptional levels of inflammatory factor genes (il-1β, tnf-α, and il-6) than those of the control group (P < 0.05). The results indicated chitosan-coated microdiet had great potential in feeding large yellow croaker larvae in addition to reducing nutrition loss. [ABSTRACT FROM AUTHOR]

Background: The dysregulation of melanin production causes skin-disfiguring ultraviolet (UV)-associated hyperpigmented spots. Previously, we found that the activation of c-Jun N-terminal kinase (JNK), a mitogen-activated protein kinase (MAPK), inhibited melanogenesis. Methods: We selected BCI-215 as it may modify MAPK expression via a known function of a dual-specificity phosphatase (DUSP) 1/6 inhibitor. B16F10 melanoma cells, Mel-ab cells, human melanocytes, and a coculture were used to assess the anti-melanogenic activity of BCI-215. The molecular mechanisms were deciphered by assaying the melanin content and cellular tyrosinase activity via immunoblotting and RT-PCR. Results: BCI-215 was found to suppress basal and cAMP-stimulated melanin production and cellular tyrosinase activity in vitro through the downregulation of microphthalmia-associated transcription factor (MITF) protein and its downstream enzymes. The reduction in MITF expression caused by BCI-215 was found to be due to all three types of MAPK activation, including extracellular signal-regulated kinase (ERK), JNK, and p38. The degree of activation was greater in ERK. A phosphorylation of the β-catenin pathway was also demonstrated. The melanin index, expression of MITF, and downstream enzymes were well-reduced in UVB-irradiated ex vivo human skin by BCI-215. Conclusions: As BCI-215 potently inhibits UV-stimulated melanogenesis, small molecules of DUSP-related signaling modulators may provide therapeutic benefits against pigmentation disorders. [ABSTRACT FROM AUTHOR]

Six previously undescribed prenylated indole diketopiperazine alkaloids, talaromyines A-F (1 − 6), were isolated from the marine-derived fungus Talaromyces purpureogenus SCSIO 41517. Their structures including absolute configurations were elucidated on the basis of comprehensive spectroscopic data including NMR, HR-ESI-MS, and electronic circular dichroism calculations, together with chemical analysis of hydrolysates. Compounds 1 − 5 represent the first example of spirocyclic indole diketopiperazines biosynthesized from the condensation of L-tryptophan and L-alanine. Compounds 2 and 4 − 5 showed selective inhibitory activities against phosphatases TCPTP and MEG2 with IC 50 value of 17.9–29.7 μM, respectively. Compounds 4 − 5 exhibited mild cytotoxic activities against two human cancer cell lines H1975 and HepG-2. Six undescribed prenylated indole diketopiperazine alkaloids, talaromyines A-F, were isolated from the marine-derived fungus Talaromyces purpureogenus. Their cytotoxicities and inhibitory activities against seven different protein tyrosine phosphatases were evaluated. [Display omitted] • Six undescribed prenylated indole diketopiperazine alkaloids were isolated from the marine-derived fungus Talaromyces purpureogenus. • Talaromyines A-E represent the first example of spirocyclic IDAs biosynthesized from the condensation of L-tryptophan and L-alanine. • The cytotoxicity and phosphatase inhibitory activity were evaluated. [ABSTRACT FROM AUTHOR]

One of the main goals of recent bioinorganic chemistry studies has been to design and synthesize novel substances to treat human diseases. The promising compounds are metal-based and metal ion binding components such as vanadium-based compounds. The potential anticancer action of vanadium-based compounds is one of area of investigation in this field. In this study, we present five oxovanadium(IV) and dioxovanadium(V) complexes as potential PTP1B inhibitors with anticancer activity against the MCF-7 breast cancer cell line, the triple negative MDA-MB-231 breast cancer cell line, and the human keratinocyte HaCaT cell line. We observed that all tested compounds were effective inhibitors of PTP1B, which correlates with anticancer activity. [VO(dipic)(dmbipy)]·2 H2O (Compound 4) and [VOO(dipic)](2-phepyH)·H2O (Compound 5) possessed the greatest inhibitory effect, with IC50 185.4 ± 9.8 and 167.2 ± 8.0 nM, respectively. To obtain a better understanding of the relationship between the structure of the examined compounds and their activity, we performed a computer simulation of their binding inside the active site of PTP1B. We observed a stronger binding of complexes containing dipicolinic acid with PTP1B. Based on our simulations, we suggested that the studied complexes exert their activity by stabilizing the WPD-loop in an open position and limiting access to the P-loop. [ABSTRACT FROM AUTHOR]

Cdc25 phosphatases have been considered promising targets for anticancer development due to the correlation of their overexpression with a wide variety of cancers. In the last two decades, the interest in this subject has considerably increased and many publications have been launched concerning this issue. An overview is constructed based on data analysis of the results of the previous publications covering the years from 1992 to 2021. Thus, the main objective of the current review is to report the chemical structures of Cdc25s inhibitors and answer the question, how to design an inhibitor with better efficacy and lower toxicity? [ABSTRACT FROM AUTHOR]

Ebselen is an organoselenium compound developed as an antioxidant and subsequently shown to be a glutathione peroxidase (GPx) mimetic. Ebselen shows some efficacy in post-stroke neuroprotection and is currently in trial for the treatment and prevention of hearing loss, Meniere's Disease and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In vitro screening studies show that ebselen is also an effective inhibitor of the enzyme inositol monophosphatase (IMPase), which is a key target of the mood-stabilising drug lithium. Further, in animal experimental studies, ebselen produces effects on the serotonin system very similar to those of lithium and also decreases behavioural impulsivity. The antidepressant effects of lithium in treatment-resistant depression (TRD) have been attributed to its ability to facilitate presynaptic serotonin activity; this suggests that ebselen might also have a therapeutic role in this condition. Human studies utilising magnetic resonance spectroscopy support the notion that ebselen, at therapeutic doses, inhibits IMPase in the human brain. Moreover, neuropsychological studies support an antidepressant profile for ebselen based on positive effects on emotional processing and reward seeking. Ebselen also lowers a human laboratory measure of impulsivity, a property that has been associated with lithium's anti-suicidal effects in patients with mood disorders. Current clinical studies are directed towards assessment of the neuropsychological effects of ebselen in TRD patients. It will also be important to ascertain whether ebselen is able to lower impulsivity and suicidal behaviour in clinical populations. The objective of this review is to summarise the developmental history, pre-clinical and clinical psychopharmacological properties of ebselen in psychiatric disorders and its potential application as a treatment for TRD. [ABSTRACT FROM AUTHOR]

Tissue‐nonspecific alkaline phosphatase (TNAP) hydrolyzes and inactivates inorganic pyrophosphate (PPi), a potent inhibitor of calcification; therefore, TNAP inhibition is a potential target to treat ectopic calcification. These two first‐in‐human studies evaluated safety, tolerability, pharmacokinetics (PKs), and pharmacodynamics (PDs) of single (SAD) and multiple‐ascending doses (MAD) of DS‐1211, a TNAP inhibitor. Healthy adults were randomized 6:2 to DS‐1211 or placebo, eight subjects per dose cohort. SAD study subjects received one dose of DS‐1211 (range, 3–3000 mg) or placebo, whereas MAD study subjects received DS‐1211 (range, 10–300 mg) once daily, 150 mg twice daily (b.i.d.), or placebo for 10 days. Primary end points were safety and tolerability. PK and PD assessments included plasma concentrations of DS‐1211, alkaline phosphatase (ALP) activity, and TNAP substrates (PPi, pyridoxal 5′‐phosphate [PLP], and phosphoethanolamine [PEA]). A total of 56 (DS‐1211: n = 42; placebo: n = 14) and 40 (DS‐1211: n = 30; placebo: n = 10) subjects enrolled in the SAD and MAD studies, respectively. In both studies, adverse events were mild or moderate and did not increase with dose. PKs of DS‐1211 were linear up to 100 mg administered as a single dose and 150 mg b.i.d. administered as a multiple‐dose regimen. In multiple dosing, there was minimal accumulation of DS‐1211. Increased DS‐1211 exposure correlated with dose‐dependent ALP inhibition and concomitant increases in PPi, PLP, and PEA. In two phase I studies, DS‐1211 appeared safe and well‐tolerated. Post‐treatment PD assessments were consistent with exposure‐dependent TNAP inhibition. These data support further evaluation of DS‐1211 for ectopic calcification diseases. [ABSTRACT FROM AUTHOR]

Objectives  Targeted inhibitors of the PI3 kinase (PI3K) pathway have shown promising but incomplete antitumor activity in preclinical chordoma models. The aim of this study is to advance methodology for a high-throughput drug screen using chordoma models to identify new combination therapies for chordoma. Study Design  Present work is an in vitro study. Setting  The study conducted at an academic research laboratory. Materials and Methods  An in vitro study on automated high-throughput screening of chordoma cells was performed using a library of 1,406 drugs as both mono- and combination therapies with PI3K inhibitors. Combination indices were determined for dual therapies and synergistic outliers were identified as potential therapeutic agents. T (brachyury) siRNA knockdown in combination with PI3K pathway inhibition was also assessed. Results  Fifty-nine combination therapies were identified as having potential therapeutic efficacy. Effective combinations included PI3K inhibitors with GSK1838705A (ALK/IGF-1R inhibitor), LY2874455 (VEGFR/FGFR inhibitor), El1 (selective Ezh2 inhibitor), and (-)-p-bromotetramisole oxalate (alkaline phosphatase inhibitor). The top ranking targets identified included ALK, PDGFR, VEGFR, aurora kinase, and BCL-2. T (brachyury) inhibition produced significant reduction in cell viability and growth; however PI3K inhibition in combination with T (brachyury) knockdown did not result in further reduction in growth and viability in vitro. Conclusion  High throughput with in vitro combination screening is feasible with chordoma cells and allows for rapid identification of synergistic dual-therapies. Potential combination therapies and targetable pathways were identified. T (brachyury) knockdown produced significant reduction in cell viability, but did not show additional benefit with PI3K pathway inhibition in this model. Further in vitro and in vivo validation of these therapeutic combinations is warranted. [ABSTRACT FROM AUTHOR]

The present study describes a novel antimicrobial mechanism based on Sodium Orthovanadate (SOV), an alkaline phosphatase inhibitor. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM) were employed to examine the surface morphologies of the test organism, Escherichia coli (E. coli), during various antibacterial phases. Our results indicated that SOV kills bacteria by attacking cell wall growth and development, leaving E. coli 's outer membrane intact. Our antimicrobial test indicated that the MIC of SOV for both E. coli and Lactococcus lactis (L. lactis) is 40 μM. A combination of quantum mechanical calculations and vibrational spectroscopy revealed that divanadate from SOV strongly coordinates with Ca2+ and Mg2+, which are the activity centers for the phosphatase that regulates bacterial cell wall synthesis. The current study is the first to propose the antibacterial mechanism caused by SOV attacking cell wall. Sodium orthovanadate inhibits undecaprenyldiphosphate phosphatases by forming complex with them, and terminates the polymerization of peptidoglycan leading to cell wall destruction and consequently, cell death. [Display omitted] • Sodium ortho-vanadate inhibits phosphatase that regulates bacterial cell wall synthesis. • Sodium ortho-vanadate kills bacteria by targeting cell wall. • Cell images indicate the cell wall damage but intact outer membrane. • Synergetic antimicrobial activity with phosphatase nanozyme [ABSTRACT FROM AUTHOR]

• Cdc25 phosphatases are key regulators of the eukaryotic cell cycle. • Cdc25A and b are overexpressed in many cancers, being key targets for drug discovery. • Molecular docking-based virtual screening was used to discover Cdc25B inhibitors. • Y11 and Y19 displayed inhibitory activity to Cdc25B. • Y19 showed anti-growth activity against the A549 cancer cell. Cell division cycle 25 (Cdc25) phosphatases play key roles in both normal and abnormal cell proliferation, which represent attractive drug targets for anticancer therapies. To discover subtype selective Cdc25B inhibitors with diverse scaffolds, a molecular docking-based virtual screening approach was performed by docking >3.8 million compounds into the Cdc25B catalytic site. An initial subset of 19 compounds was selected and assayed, and most compounds showed Cdc25B enzyme inhibition activity at 200 μM. Among these, 2 structurally diverse compounds Y11 (IC 50 = 156.30 ± 7.19 μM) and Y19 (IC 50 = 118.85 ± 12.07 μM) displayed micromolar inhibitory activity and subtype selectivity to Cdc25B phosphatases. Y19 was found to have anti-growth activity against the A549 cancer cell at micromolar profile. Additionally, molecular dynamics (MD) simulations and binding free energy calculations (MM/GBSA) were done to elucidate the binding mechanisms. The predicated ADMET properties suggested that Y11 and Y19 could serve as starting points for development of subtype selective Cdc25B phosphatases inhibitors. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Eysenhardtia officinalis bark is traditionally used for the treatment of diabetes in the Hidalgo state of Mexico. • The ethanol-water extract of E. officinalis contains flavonoids; vitexin was isolated and identified. • E. officinalis did not exert an acute toxic effect and could manage fasting and postprandial hyperglycemia. • The hypoglycemic mechanisms identified were the gluconeogenesis inhibition and an increase in insulin sensitivity. • E. officinalis inhibited gluconeogenic rate-limiting enzymes glucose-6-phosphatase and fructose-1,6-bisphosphatase. [ABSTRACT FROM AUTHOR]

Development of potent and specific inhibitors of protein tyrosine phosphatase 1B (PTP1B) with desired drug‐like properties is still a challenge. Based on the crystal structures of PTP1B transition state analog consisting of a vanadate peptide, a novel approach is proposed to design PTP1B inhibitors, in which the tyrosyl vanadate ester of a PTP1B peptide mimic (PL1) is stably integrated on the membrane permeable graphene quantum dots (GQDs). The vanadate complexes (GQD‐PL1‐VV) prepared exhibit high potency (Ki = 6 ± 1 × 10−9m) and selectivity (selectivity index SI >200 for PTP1B versus the T‐cell protein tyrosine phosphatase, TCPTP) in solution and in HepG2 cells. Oral administration of GQD‐PL1‐VV in db/db model mice shows selective PTP1B inhibition in liver and fat tissues and exhibits improved anti‐diabetic activity compared to bis(maltolato)oxovanadium(IV). Moreover, exchange of PL1 to a TCPTP‐specific ligand (PL2) results in potent TCPTP inhibition (Ki = 59 ± 12 × 10−9m) as expected with SI ≈23 versus PTP1B. Overall, the present results provide a paradigm shift and a general design of phosphatase inhibitors consisting of GQDs, a complexing targeting ligand and vanadium (V) for selective regulation of PTP1B both in vitro and vivo. [ABSTRACT FROM AUTHOR]

Objectives  Targeted inhibitors of the PI3 kinase (PI3K) pathway have shown promising but incomplete antitumor activity in preclinical chordoma models. The aim of this study is to advance methodology for a high-throughput drug screen using chordoma models to identify new combination therapies for chordoma. Study Design  Present work is an in vitro study. Setting  The study conducted at an academic research laboratory. Materials and Methods  An in vitro study on automated high-throughput screening of chordoma cells was performed using a library of 1,406 drugs as both mono- and combination therapies with PI3K inhibitors. Combination indices were determined for dual therapies and synergistic outliers were identified as potential therapeutic agents. T (brachyury) siRNA knockdown in combination with PI3K pathway inhibition was also assessed. Results  Fifty-nine combination therapies were identified as having potential therapeutic efficacy. Effective combinations included PI3K inhibitors with GSK1838705A (ALK/IGF-1R inhibitor), LY2874455 (VEGFR/FGFR inhibitor), El1 (selective Ezh2 inhibitor), and (-)-p-bromotetramisole oxalate (alkaline phosphatase inhibitor). The top ranking targets identified included ALK, PDGFR, VEGFR, aurora kinase, and BCL-2. T (brachyury) inhibition produced significant reduction in cell viability and growth; however PI3K inhibition in combination with T (brachyury) knockdown did not result in further reduction in growth and viability in vitro. Conclusion  High throughput with in vitro combination screening is feasible with chordoma cells and allows for rapid identification of synergistic dual-therapies. Potential combination therapies and targetable pathways were identified. T (brachyury) knockdown produced significant reduction in cell viability, but did not show additional benefit with PI3K pathway inhibition in this model. Further in vitro and in vivo validation of these therapeutic combinations is warranted. [ABSTRACT FROM AUTHOR]