Antagonizing EZH2 combined with vitamin D3 exerts a synergistic role in anti-fibrosis through bidirectional effects on hepatocytes and hepatic stellate cells.

BACKGROUND AND AIM: Whether vitamin D3 (VD3) supplementation is associated with improved liver fibrosis is controversial. METHODS: Liver fibrosis models were treated with VD3, active VD (1,25-OH2 Vitamin D3), or collaboration with GSK126 (Ezh2 inhibitor), respectively. Hepatic stellate cells (HSCs) were co-cultured with hepatocytes and then stimulated with TGF-ß. Autophagy of hepatocytes was determined after the intervention of 1,25-OH2 Vitamin D3 and GSK126. Also, the active status of HSCs and the mechanism with 1,25-OH2 Vitamin D3 and GSK126 intervention were detected. RESULTS: 1,25-OH2 Vitamin D3, but not VD3, is involved in anti-fibrosis and partially improves liver function, which might be associated with related enzymes and receptors (especially CYP2R1), leading to decreased of its biotransformation. GSK126 plays a synergistic role in anti-fibrosis. The co-culture system showed increased hepatocyte autophagy after HSCs activation. Supplementation with 1,25-OH2 Vitamin D3 or combined GSK126 reduced these effects. Further studies showed that 1,25-OH2 Vitamin D3 promoted H3K27 methylation of DKK1 promoter through VDR/Ezh2 due to the weakening for HSCs inhibitory signal. CONCLUSIONS: VD3 bioactive form 1,25-OH2 Vitamin D3 is responsible for the anti-fibrosis, which might have bidirectional effects on HSCs by regulating histone modification. The inhibitor of Ezh2 plays a synergistic role in this process.

Discovery and characterization of amentoflavone as a naturally occurring inhibitor against the bile salt hydrolase produced by Lactobacillus salivarius.

Bile salt hydrolases (BSHs), a group of cysteine-hydrolases produced by gut microbes, play a crucial role in the hydrolysis of glycine- or taurine-conjugated bile acids and have been validated as key targets to modulate bile acid metabolism. This study aims to discover one or more efficacious inhibitors against a BSH produced by Lactobacillus salivarius (lsBSH) from natural products and to characterize the mechanism of the newly identified BSH inhibitor(s). Following screening of the inhibition potentials of more than 100 natural compounds against lsBSH, amentoflavone (AMF), a naturally occurring biflavone isolated from various medicinal plants, was discovered to be an efficacious BSH inhibitor (IC50 = 0.34 µM). Further investigation showed that AMF could strongly inhibit the lsBSH-catalyzed hydrolytic reaction in living gut microbes. Inhibition kinetic analyses demonstrated that AMF reversibly inhibited the lsBSH-catalyzed hydrolytic reaction in a mixed-inhibition manner, with an apparent Ki value of 0.65 µM. Fluorescence quenching assays suggested that AMF could quench the fluorescence of lsBSH via a static quenching procedure. Docking simulations suggested that AMF could be fitted into lsBSH at two distinct ligand-binding sites, mainly via hydrophobic interactions and hydrogen bonding, which explained well the mixed inhibition mode of this agent. Animal tests showed that the hydrolytic activities of BSHs in mice feces could be significantly blocked by AMF. In summary, this study reports that AMF is a strong, naturally occurring inhibitor of lsBSH, which offers a promising lead compound to develop novel agents for modulating bile acid metabolism in the host via targeting BSHs.

Targeting the ATP synthase in bacterial and fungal pathogens: beyond Mycobacterium tuberculosis.

The ATP synthase is a multicomponent enzyme that is largely conserved across the kingdoms of life. In many species the ATP synthase is central in the synthesis of ATP by using the electrochemical proton gradient generated via the electron transport chain. Bacteria inhabit very diverse ecological niches; hence their metabolism to extract nutrients and generation of ATP varies from species to species. Some species are obligate aerobes (e.g., Mycobacterium tuberculosis), relying on oxidative phosphorylation for ATP synthesis, whereas others are strict anaerobes (e.g., Clostridioides difficile) relying primarily on substrate-level phosphorylation using various fermentative pathways. Yet other species, such as Staphylococcus aureus and Escherichia coli are facultative anaerobes and can convert energy via both respiratory and fermentative pathways. The metabolic propensity and growth conditions experienced by bacterial species have a great impact on the necessity of a functional ATP synthase for viability. The ATP synthase has been validated as a druggable target with the approval of the ATP synthase inhibitor bedaquiline for treatment of M. tuberculosis, an organism in which the ATP synthase is essential for growth. Currently, no ATP synthase inhibitors are in clinical use against non-mycobacterial pathogens. In this review, the physiological functions of the ATP synthase in various bacterial pathogens are discussed in relation to the metabolic pathways utilized for providing energy. The ATP synthase is essential in important pathogenic species that are obligate aerobes, obligate anaerobes and aerotolerant anaerobes, whereas it is dispensable for growth in most facultative anaerobic pathogens. Interference with the ATP synthase in facultative anaerobes has physiological consequences, such as membrane hyperpolarization, which can be exploited for combination therapies. Collectively, the available data indicate that the ATP synthase is an interesting target for development of new antimicrobials beyond M. tuberculosis.

Synthesis and Evaluation of Structurally Diverse C-2-Substituted Thienopyrimidine-Based Inhibitors of the Human Geranylgeranyl Pyrophosphate Synthase.

Novel analogues of C-2-substituted thienopyrimidine-based bisphosphonates (C2-ThP-BPs) are described that are potent inhibitors of the human geranylgeranyl pyrophosphate synthase (hGGPPS). Members of this class of compounds induce target-selective apoptosis of multiple myeloma (MM) cells and exhibit antimyeloma activity in vivo. A key structural element of these inhibitors is a linker moiety that connects their (((2-phenylthieno[2,3-d]pyrimidin-4-yl)amino)methylene)bisphosphonic acid core to various side chains. The structural diversity of this linker moiety, as well as the side chains attached to it, was investigated and found to significantly impact the toxicity of these compounds in MM cells. The most potent inhibitor identified was evaluated in mouse and rat for liver toxicity and systemic exposure, respectively, providing further optimism for the potential value of such compounds as human therapeutics.

A new porphyrin as selective substrate-based inhibitor of breast cancer resistance protein (BCRP/ABCG2).

The ABCG2 transporter plays a pivotal role in multidrug resistance, however, no clinical trial using specific ABCG2 inhibitors have been successful. Although ABC transporters actively extrude a wide variety of substrates, photodynamic therapeutic agents with porphyrinic scaffolds are exclusively transported by ABCG2. In this work, we describe for the first time a porphyrin derivative (4B) inhibitor of ABCG2 and capable to overcome multidrug resistance in vitro. The inhibition was time-dependent and 4B was not itself transported by ABCG2. Independently of the substrate, the porphyrin 4B showed an IC50 value of 1.6 µM and a mixed type of inhibition. This compound inhibited the ATPase activity and increased the binding of the conformational-sensitive antibody 5D3. A thermostability assay confirmed allosteric protein changes triggered by the porphyrin. Long-timescale molecular dynamics simulations revealed a different behavior between the ABCG2 porphyrinic substrate pheophorbide a and the porphyrin 4B. Pheophorbide a was able to bind in three different protein sites but 4B showed one binding conformation with a strong ionic interaction with GLU446. The inhibition was selective toward ABCG2, since no inhibition was observed for P-glycoprotein and MRP1. Finally, this compound successfully chemosensitized cells that overexpress ABCG2. These findings reinforce that substrates may be a privileged source of chemical scaffolds for identification of new inhibitors of multidrug resistance-linked ABC transporters.

Novel Quinic Acid Glycerates from Tussilago farfara Inhibit Polypeptide GalNAc-Transferase.

The discovery of a bioactive inhibitor tool for human polypeptide N-acetylgalactosaminyl transferases (GalNAc-Ts), the initiating enzyme for mucin-type O-glycosylation, remains challenging. In the present study, we identified an array of quinic acid derivatives, including four new glycerates (1-4) from Tussilago farfara, a traditional Chinese medicinal plant, as active inhibitors of GalNAc-T2 using a combined screening approach with a cell-based T2-specific sensor and purified enzyme assay. These inhibitors dose-dependently inhibited human GalNAc-T2 but did not affect O-linked N-acetylglucosamine transferase (OGT), the other type of glycosyltransferase. Importantly, they are not cytotoxic and retain inhibitory activity in cells lacking elongated O-glycans, which are eliminated by the CRISPR/Cas9 gene editing tool. A structure-activity relationship study unveiled a novel quinic acid-caffeic acid conjugate pharmacophore that directs inhibition. Overall, these new natural product inhibitors could serve as a basis for developing an inhibitor tool for GalNAc-T2.

Phytochemical Screening and Antioxidant Activity of Seven Native Species Growing in the Forests of Southern Chilean Patagonia.

The genus Nothofagus is one of the most abundant in the subantarctic Patagonian forests. Five species inhabit these ecosystems, three evergreen (Nothofagus betuloides, Nothofagus dombeyi, and Nothofagus nitida) and two deciduous (Nothofagus pumilio and Nothofagus antarctica). This is the first report on the levels of secondary metabolites and the antioxidant capacity of Patagonian tree species growing in natural environments. The aim of this work was to carry out a phytochemical screening, to determine the antioxidant capacity, the sun protection factor, and the α-glucosidase and tyrosinase inhibitory activity of foliar extracts of the five previous species. Besides, Aristotelia chilensis and Berberis microphylla, two species of Patagonian shrubs growing in the same forests, were used as reference. N. dombeyi was the Nothofagus with the best antioxidant capacity. B. microphylla differed from all studied species. Moreover, the Nothofagus was split into two groups. N. betuloides and N. dombeyi are the most similar species to A. chilensis. The α-glucosidase was completely inhibited by all studied extracts. Furthermore, N. antarctica, N.pumilio, and N. nitida inhibited about 70% of the tyrosinase activity. All the results found in this study for the species of the genus Nothofagus support further research on their potential beneficial properties for human health.

Structure-based virtual screening and computational study towards identification of novel inhibitors of hypoxanthine-guanine phosphoribosyltransferase of Trypanosoma cruzi.

Hypoxanthine-guanine phosphoribosyltransferase (HGPRT) is the key regulatory enzyme of the purine salvage pathway present in the members of trypanosomatids. The parasite solely depends on this pathway for the synthesis of nucleotides due to the absence of the de novo pathway. This study intends to identify putative inhibitors towards Trypanosoma cruzi HGPRT (TcHGPRT). Initial virtual screening was performed with substructures of phosphoribosyl pyrophosphate (PRPP), an original substrate of HGPRT. Twenty compounds that had greater binding energy than the substrate was treated as hits and was further screened and narrowed down through induced fit docking which resulted in top five compounds which was distinguished into two groups based on the ligand occupancy within the PRPP binding site of TcHGPRT. Group-I compounds (PubChem CID 130316561 and 134978234) are analogous to PRPP structure with greater occupancy, were preferred over Group-II compounds which had lesser occupancy than the substrate. However, one compound (22404820) among Group II was chosen for further analysis considering its significant electrostatic interactions. Molecular docking studies revealed the requirement of an electronegative moiety like phosphate group to be present in the ligand due to the presence of metal ions in the substrate binding site. The three chosen compounds along with PRPP were subjected to molecular dynamics analysis, which indicated a strong presence of electrostatic interaction. Considering the dynamic stability of interactions as well as pharmacological properties of ligands based on absorption, distribution, metabolism, excretion prediction, Group-I compounds were selected as lead compounds and were subjected to molecular electrostatic potential analysis to determine the charge distribution of the compound. The overall analysis thus suggests both 130316561 and 134978234 can be used as TcHGPRT inhibitors. Furthermore, these computational results emphasize the requirement of phosphorylated ligands which are essential in mediating electrostatic interactions and to compete with the binding affinity of the original substrate.

Biological Insights and NMR Metabolic Profiling of Different Extracts of Spermacoce verticillata (L.) G. Mey.

Spermacoce verticillata (L.) G. Mey. is commonly used in the folk medicine by various cultures to manage common diseases. Herein, the chemical and biological profiles of S. verticillata were studied in order to provide a comprehensive characterization of bioactive compounds and also to highlight the therapeutic properties. The in vitro antioxidant activity using free-radical scavenging, phosphomolybdenum, ferrous-ion chelating and reducing power assays, and the inhibitory activity against key enzymes such as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), tyrosinase, α-amylase and α-glucosidase of S. verticillata extracts (dichloromethane, ethyl acetate, methanol and water) were investigated. The highest total phenolic and flavonoid content were observed in the methanolic and aqueous extracts. Exhaustive 2DNMR investigation has revealed the presence of rutin, ursolic and oleanoic acids. The methanolic extract, followed by aqueous extract have showed remarkable free radical quenching and reducing ability, while the dichloromethane extract was the best source of metal chelators. The tested extracts showed notable inhibitory activity against cholinesterases (AChE: 1.63-4.99 mg GALAE/g extract and BChE: 12.40-15.48 mg GALAE/g extract) and tyrosinase (60.85-159.64 mg KAE/g extract). No inhibitory activity was displayed by ethyl acetate and aqueous extracts against BChE and tyrosinase, respectively. All the tested extracts showed modest α-amylase inhibitory activity, while only the ethyl acetate and aqueous extracts were potent against α-glycosidase. This study further validates the use of S. verticillata in the traditional medicine, while advocating for further investigation for phytomedicine development.

Discovery of novel inhibitors of human phosphoglycerate dehydrogenase by activity-directed combinatorial chemical synthesis strategy.

Serine, the source of the one-carbon units essential for de novo purine and deoxythymidine synthesis plays a crucial role in the growth of cancer cells. Phosphoglycerate dehydrogenase (PHGDH) which catalyzes the first, rate-limiting step in de novo serine biosynthesis has become a promising target for the cancer treatment. Here we identified H-G6 as a potential PHGDH inhibitor from the screening of an in-house small molecule library based on the enzymatic assay. We adopted activity-directed combinatorial chemical synthesis strategy to optimize this hit compound. Compound b36 was found to be the noncompetitive and the most promising one with IC50 values of 5.96 ± 0.61 µM against PHGDH. Compound b36 inhibited the proliferation of human breast cancer and ovarian cancer cells, reduced intracellular serine synthesis, damaged DNA synthesis, and induced cell cycle arrest. Collectively, our results suggest that b36 is a novel PHGDH inhibitor, which could be a promising modulator to reprogram the serine synthesis pathway and might be a potential anticancer lead worth further exploration.

Discovery of a potent and selective inhibitor of histone lysine demethylase KDM4D.

Histone lysine demethylase 4D (KDM4D) plays an important role in the regulation of tumorigenesis, progression and drug resistance and has been considered a potential target for cancer treatment. However, there is still a lack of potent and selective KDM4D inhibitors. In this investigation, we report a new class of KDM4D inhibitors containing the 2-(aryl(pyrrolidine-1-yl)methyl)phenol scaffold, identified through AlphaLisa-based screening, structural optimization, and structure-activity relationship analyses. Among these inhibitors, 24s was the most potent, with an IC50 value of 0.023 ± 0.004 µM. This compound exhibited more than 1500-fold selectivity towards KDM4D versus KDM4A as well as other JMJD subfamily members, indicating good selectivity for KDM4D. Kinetic analysis indicated that 24s did not occupy the 2-oxoglutarate binding pocket. In an in vitro assay, 24s significantly suppressed the proliferation and migration of colorectal cancer (CRC) cells. Overall, this study has identified a good tool compound to explore the biological function of KDM4D and a good lead compound for drug discovery targeting KDM4D.

A comprehensive phytochemical, biological, toxicological and molecular docking evaluation of Suaeda fruticosa (L.) Forssk.: An edible halophyte medicinal plant.

Suaeda fruticosa is an edible medicinal halophyte known for its traditional uses. In this study, methanol and dichloromethane extracts of S. fruticosa were explored for phytochemical, biological and toxicological parameters. Total phenolic and flavonoid constituents were determined by using standard aluminum chloride and Folin-Ciocalteu methods, and UHPLC-MS analysis of methanol extract was performed for tentative identification of secondary metabolites. Different standard methods like DPPH, ABTS, FRAP, CUPRAC, total antioxidant capacity (TAC), and metal chelation assays were utilized to find out the antioxidant potential of extracts. Enzyme inhibition studies of extracts against acetylcholinesterase, butyrylcholinesterase, tyrosinase, α-amylase and, α-glucosidase enzymes were also studied. Likewise, the cytotoxicity was also assessed against MCF-7, MDA-MB-231, and DU-145 cell lines. The higher phenolic and flavonoids contents were observed in methanol extracts which can be correlated to its higher radical scavenging potential. Similarly, 11 different secondary metabolites were tentatively identified by UHPLC profiling. Both the extract showed significant inhibition against all the enzymes except for α-glucosidase. Moreover, docking studies were also performed against the tested enzymes. In the case of cytotoxicity, both the samples were found moderately toxic against the tested cell lines. This plant can be explored further for its potential therapeutic and edible uses.

Design, synthesis and biological evaluation of selective hybrid coumarin-thiazolidinedione aldose reductase-II inhibitors as potential antidiabetics.

Thiazolidinediones (TZD), benzopyrans are the proven scaffolds for inhibiting Aldose reductase (ALR2) activity and their structural confluence with the retention of necessary fragments helped in designing a series of hybrid compounds 2-(5-cycloalkylidene-2,4-dioxothiazolidin-3-yl)-N-(2-oxo-2H-chromen-3-yl)acetamide (10a-n) for better ALR2 inhibition. The compounds were synthesized by treating substituted 3-(N-bromoacetyl amino)coumarins (9a-d) with potassium salt of 5-cyclo alkylidene-1,3-thiazolidine-2,4-diones (4a-d). The inhibition activity against ALR2 with IC50 values range from 0.012 ± 0.001 to 0.056 ± 0.007 µM. N-[(6-Bromo-3-coumarinyl)-2-(5-cyclopentylidene-2,4-dioxothiazolidin-3-yl)] acetamide (10c) with cyclopentylidene group on one end and the 6-bromo group on the other end showed better inhibitory property (IC50 = 0.012 µM) and selectivity index (324.166) against the ALR2, a forty fold superiority over sorbinil, a better molecule over epalrestat and rest of the analogues exhibited a far superior response over sorbinil and slightly better as compared with epalrestat. It was further confirmed by the insilico studies that compound 10c showed best inhibition activity among the synthesized compounds with a high selectivity index against the ALR2. In invivo experiments, supplementation of compound 10c to STZ induced rats delayed the progression of cataract in a dose-dependent manner warranting its further development as a potential agent to treat thediabetic secondary complications especially cataract.

A Prospective of Multiple Biopharmaceutical Activities of Procyanidins-Rich Uapaca togoensis Pax Extracts: HPLC-ESI-TOF-MS Coupled with Bioinformatics Analysis.

The article reports the chemical composition, antioxidant, six key enzymes inhibitory and antimicrobial activities of two solvent extracts (water and methanol) of leaves and stem bark of Uapaca togoensis. For chemical composition, methanol extract of stem bark exhibited significant higher total phenolic (129.86 mg GAE/g) and flavanol (10.44 mg CE/g) contents. Methanol extract of leaves and water extract of stem bark showed high flavonoids (20.94 mg RE/g) and phenolic acid (90.40 mg CAE/g) content, respectively. In addition, HPLC-ESI-TOF-MS analysis revealed that U. togoensis was rich in procyanidins. The methanol and water extracts of stem bark had overall superior antioxidant activity; however, only methanol extract of stem bark showed higher inhibition of cholinesterase (AChE: 2.57 mg GALAE/g; BChE: 4.69 mg GALAE/g), tyrosinase (69.53 mg KAE/g) and elastase (2.73 mmol CE/g). Potent metal chelating ability was showed by water extract of leaves (18.94 mg EDTAE/g), higher inhibition of amylase was detected for water extracts of leaves (0.94 mmol ACAE/g) and stem bark (0.92 mmol ACAE/g). The tested extracts have shown wide-spectrum antibacterial properties and these effects have shown to be more effective against Aspergillus ochraceus, Penicillium funiculosum, Trichoderma viride, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. The results revealed that the antioxidant, enzyme inhibitory and antimicrobial activities depended on the extraction solvents and the parts of plant. Bioinformatics analysis on the 17 major compounds showed modulation of pathway associated with cancer. In brief, U. togoensis might be valuable as potential source of natural agents for therapeutic application.

Evaluation of Antioxidant, Anti-Inflammatory and Antityrosinase Potential of Extracts from Different Aerial Parts of Rhanterium suaveolens from Tunisia.

The genus Rhanterium (Asteraceae) is a widely distributed medicinal plant throughout western North Africa and some Rhanterium species are used in folk medicine. The aim of research was to investigate methanolic extracts from different parts (flowers, leaves, and stems) of Tunisian Rhanterium suaveolens as potential sources of bioactive products useful for healthy purposes. In particular, were analyzed the phenolic composition of these extracts and their antioxidant, anti-inflammatory, and anti-tyrosinase properties. The phytochemical analyses were performed using standard colorimetric procedures, HPLC-DAD and HPLC-DAD-ESI-MS. Then, several in vitro cell-free assays have been used to estimate the antioxidant/free radical scavenging capability of the extracts. Moreover, in vitro, and in vivo anti-melanogenesis activities of these extracts were tested, respectively, with the tyrosinase inhibition assay and the Zebrafish embryo model. Finally, the anti-inflammatory potential of these extracts in an in vitro model of acute intestinal inflammation in differentiated Caco-2 cells was evaluated. The R. suaveolens extracts under study appeared particularly rich in flavonols and hydroxycinnamic acids and all extracts appeared endowed with good antioxidant/free radical scavenging properties, being the flower extracts slightly more active than the others. Moreover, R. suaveolens flowers extract was able to inhibit in vitro tyrosinase activity and exhibited bleaching effects on the pigmentation of zebrafish embryos. Furthermore, all extracts showed good anti-inflammatory activity in intestinal epithelial cells as demonstrated by the inhibition of TNF-α-induced gene expression of IL-6 and IL-8. R. suaveolens aerial parts may be considered as a potential source of whitening agents, as well as of agents for the treatment of disorders related to oxidative stress and inflammation.

Phytochemical Fingerprints and Bioactivities of Ripe Disseminules (Fruit-Seeds) of Seventeen Gundelia (Kenger-Kereng Dikeni) Species from Anatolia with Chemometric Approach.

Gundelia species are known as "Kenger-kereng dikeni" in Anatolia, and their aerial parts are consumed as food. Also, roots and seeds (disseminules) of the Gundelia species are used to prepare gum and coffee. The chemical contents of ethanol and hexane extracts of disseminules of 17 Gundelia species, 13 of them are endemic, were studied using LC/MS/MS and GC/MS. Additionally, their antioxidant potential and enzyme inhibitory capacity against acetyl- and butyryl-cholinesterase, urease, and tyrosinase were determined. The unsaturated fatty acid ratios of Gundelia species were higher than their saturated fatty acid ratio. The highest sum of oleic and linoleic acid was detected in G. tournefortii var. tenuisecta (70.42 %). ß-Sitosterol, α-amyrin, 3-acetyllupeol were identified in 17 Gundelia species by GC/MS, while chlorogenic acid and luteolin by LC/MS/MS as major compounds. The ethanol and hexane extracts of G. siirtica, G. rosea, and G. mesopotamica indicated good cholinesterase inhibitory activity. Among all species, ethanol extract of G. colemerikensis exhibited the best activity in ABTS (IC50 : 32.30±0.98 µg/mL), DPPH (IC50 : 59.91±0.89 µg/mL), and CUPRAC (A0.5 : 57.41±1.03 µg/mL) assays. Ethanol extract of G. colemerikensis also displayed the highest inhibitory activity against butyrylcholinesterase (51.14±0.25 % at 200 µg/mL), urease (51.71±1.75 % at 200 µg/mL), and tyrosinase (39.50±0.85 % at 200 µg/mL) enzymes. According to the chemometric analysis of fatty acids, four groups were observed. Therefore, it is suggested that G. colemerikensis can be used in the pharmaceutical, food, and cosmetic industries due to its antioxidant and enzyme inhibition properties.

Discovery and Optimization of 2H-1λ2-Pyridin-2-one Inhibitors of Mutant Isocitrate Dehydrogenase 1 for the Treatment of Cancer.

Neomorphic mutations in isocitrate dehydrogenase 1 (IDH1) are oncogenic for a number of malignancies, primarily low-grade gliomas and acute myeloid leukemia. We report a medicinal chemistry campaign around a 7,7-dimethyl-7,8-dihydro-2H-1λ2-quinoline-2,5(6H)-dione screening hit against the R132H and R132C mutant forms of isocitrate dehydrogenase (IDH1). Systematic SAR efforts produced a series of potent pyrid-2-one mIDH1 inhibitors, including the atropisomer (+)-119 (NCATS-SM5637, NSC 791985). In an engineered mIDH1-U87-xenograft mouse model, after a single oral dose of 30 mg/kg, 16 h post dose, between 16 and 48 h, (+)-119 showed higher tumoral concentrations that corresponded to lower 2-HG concentrations, when compared with the approved drug AG-120 (ivosidenib).

Discovery of Orally Bioavailable Purine-Based Inhibitors of the Low-Molecular-Weight Protein Tyrosine Phosphatase.

Obesity-associated insulin resistance plays a central role in the pathogenesis of type 2 diabetes. A promising approach to decrease insulin resistance in obesity is to inhibit the protein tyrosine phosphatases that negatively regulate insulin receptor signaling. The low-molecular-weight protein tyrosine phosphatase (LMPTP) acts as a critical promoter of insulin resistance in obesity by inhibiting phosphorylation of the liver insulin receptor activation motif. Here, we report development of a novel purine-based chemical series of LMPTP inhibitors. These compounds inhibit LMPTP with an uncompetitive mechanism and are highly selective for LMPTP over other protein tyrosine phosphatases. We also report the generation of a highly orally bioavailable purine-based analogue that reverses obesity-induced diabetes in mice.

Zhuyu Annao decoction promotes angiogenesis in mice with cerebral hemorrhage by inhibiting the activity of PHD3.

Some traditional Chinese decoctions, such as Zhuyu Annao, exert favorable therapeutic effects on acute cerebral hemorrhage, hemorrhagic stroke, and other neurological diseases, but the underlying mechanism remains unclear. This study aimed to determine whether Zhuyu Annao decoction (ZYAND) protects the injured brain by promoting angiogenesis following intracerebral hemorrhage (ICH) and elucidate its specific mechanism. The effect of ZYAND on the nervous system of mice after ICH was explored through behavioral experiments, such as the Morris water maze and Rotarod tests, and its effects on oxidative stress were explored by detecting several oxidative stress markers, including malondialdehyde, nitric oxide, glutathione peroxidase, and superoxide dismutase. Real-time quantitative RT-PCR and WB were used to detect the effects of ZYAND on the levels of prolyl hydroxylase domain 3 (PHD3), hypoxia-inducible factor-1α (HIF-1α), and vascular endothelial growth factor (VEGF) in the brain tissues of mice. The effect of ZYAND on the NF-κB signaling pathway was detected using a luciferase reporter gene. A human umbilical cord vascular endothelial cell angiogenesis experiment was performed to determine whether ZYAND promotes angiogenesis. The Morris water maze test and other behavioral experiments verified that ZYAND improved the neurobehavior of mice after ICH. ZYAND activated the PHD3/HIF-1α signaling pathway, inhibiting the oxidative damage caused by ICH. In angiogenesis experiments, it was found that ZYAND promoted VEGF-induced angiogenesis by upregulating the expression of HIF-1α, and NF-κB signaling regulated the expression of HIF-1α by inhibiting PHD3. ZYAND exerts a reparative effect on brain tissue damaged after ICH through the NF-κB/ PHD3/HIF-1α/VEGF signaling axis.

Nucleotide analogues containing a pyrrolidine, piperidine or piperazine ring: Synthesis and evaluation of inhibition of plasmodial and human 6-oxopurine phosphoribosyltransferases and in vitro antimalarial activity.

Parasites of the Plasmodium genus are unable to produce purine nucleotides de novo and depend completely on the salvage pathway. This fact makes plasmodial hypoxanthine-guanine-(xanthine) phosphoribosyltransferase [HG(X)PRT] a valuable target for development of antimalarial agents. A series of nucleotide analogues was designed, synthesized and evaluated as potential inhibitors of Plasmodium falciparum HGXPRT, P. vivax HGPRT and human HGPRT. These novel nucleoside phosphonates have a pyrrolidine, piperidine or piperazine ring incorporated into the linker connecting the purine base to a phosphonate group(s) and exhibited a broad range of Ki values between 0.15 and 72 µM. The corresponding phosphoramidate prodrugs, able to cross cell membranes, have been synthesized and evaluated in a P. falciparum infected human erythrocyte assay. Of the eight prodrugs evaluated seven exhibited in vitro antimalarial activity with IC50 values within the range of 2.5-12.1 µM. The bis-phosphoramidate prodrug 13a with a mean (SD) IC50 of 2.5 ± 0.7 µM against the chloroquine-resistant P. falciparum W2 strain exhibited low cytotoxicity in the human hepatocellular liver carcinoma (HepG2) and normal human dermal fibroblasts (NHDF) cell lines at a concentration of 100 µM suggesting good selectivity for further structure-activity relationship investigations.