Evaluation of antibacterial, cytotoxicity, and apoptosis activity of novel chromene-sulfonamide hybrids synthesized under solvent-free conditions and 3D-QSAR modeling studies.

In this study, eleven novel chromene sulfonamide hybrids were synthesized by a convenient method in accordance with green chemistry. At first, chromene derivatives (1-9a) were prepared through the multi-component reaction between aryl aldehydes, malononitrile, and 3-aminophenol. Then, synthesized chromenes were reacted with appropriate sulfonyl chlorides by grinding method to give the corresponding chromene sulfonamide hybrids (1-11b). Synthesized hybrids were obtained in good to high yield and characterized by IR, 1HNMR, 13CNMR, CHN and melting point techniques. In addition, the broth microdilution assay was used to determine the minimal inhibitory concentration of newly synthesized chromene-sulfonamide hybrids. The MTT test was used to determine the cytotoxicity and apoptotic activity of the newly synthesized compounds against fibroblast L929 cells. The 3D­QSAR analysis confirmed the experimental assays, demonstrating that our predictive model is useful for developing new antibacterial inhibitors. Consequently, molecular docking studies were performed to validate the findings of the 3D-QSAR analysis, confirming the potential binding interactions of the synthesized chromene-sulfonamide hybrids with the target enzymes. Molecular docking studies were employed to support the 3D-QSAR predictions, providing insights into the binding interactions between the newly synthesized chromene-sulfonamide hybrids and their target bacterial enzymes, thereby reinforcing the potential efficacy of these compounds as antibacterial agents. Also, some of the experimental outcomes supported or conflicted with the pharmacokinetic prediction (especially about compound carcinogenicity). The performance of ADMET predictor results was assessed. The work presented here proposes a computationally driven strategy for designing and discovering a new sulfonamide scaffold for bacterial inhibition.

Regulation of cellular and molecular markers of epithelial-mesenchymal transition by Brazilin in breast cancer cells.

Breast cancer is the most common invasive neoplasm and the leading cause of cancer death in women worldwide. The main cause of mortality in cancer patients is invasion and metastasis, where the epithelial-mesenchymal transition (EMT) is a crucial player in these processes. Pharmacological therapy has plants as its primary source, including isoflavonoids. Brazilin is an isoflavonoid isolated from Haematoxilum brasiletto that has shown antiproliferative activity in several cancer cell lines. In this study, we evaluated the effect of Brazilin on canonical markers of EMT such as E-cadherin, vimentin, Twist, and matrix metalloproteases (MMPs). By Western blot, we evaluated E-cadherin, vimentin, and Twist expression and the subcellular localization by immunofluorescence. Using gelatin zymography, we determined the levels of secretion of MMPs. We used Transwell chambers coated with matrigel to determine the in vitro invasion of breast cancer cells treated with Brazilin. Interestingly, our results show that Brazilin increases 50% in E-cadherin expression and decreases 50% in vimentin and Twist expression, MMPs, and cell invasion in triple-negative breast cancer (TNBC) MDA-MB-231 and to a lesser extend in MCF7 ER+ breast cancer cells. Together, these findings position Brazilin as a new molecule with great potential for use as complementary or alternative treatment in breast cancer therapy in the future.

Effect of humic substances on the fraction of heavy metal and microbial response.

Contamination of soils by Molybdenum (Mo) has raised increasing concern worldwide. Both fulvic acid (FA) and humic acid (HA) possess numerous positive properties, such as large specific surface areas and microporous structure that facilitates the immobilization of the heavy metal in soils. Despite these characteristics, there have been few studies on the microbiology effects of FA and HA. Therefore, this study aimed to assess the Mo immobilization effects of FA and HA, as well as the associated changes in microbial community in Mo-contaminated soils (with application rates of 0%, 0.5% and 1.0%). The result of the incubation demonstrated a decrease in soil pH (from 8.23 ~ 8.94 to 8.05 ~ 8.77). Importantly, both FA and HA reduced the exchangeable fraction and reducible fraction of Mo in the soil, thereby transforming Mo into a more stable form. Furthermore, the application of FA and HA led to an increase in the relative abundance of Actinobacteriota and Firmicutes, resulting in alterations to the microbial community structure. However, it is worth noting that due to the differing structures and properties of FA and HA, these outcomes were not entirely consistent. In summary, the aging of FA and HA in soil enhanced their capacity to immobilization Mo as a soil amendment. This suggests that they have the potential to serve as effective amendments for the remediation of Mo-contaminated soils.

Exploring the antifungal, antibiofilm and antienzymatic potential of Rottlerin in an in vitro and in vivo approach.

Candida species have been responsible for a high number of invasive infections worldwide. In this sense, Rottlerin has demonstrated a wide range of pharmacological activities. Therefore, this study aimed to evaluate the antifungal, antibiofilm and antivirulence activity of Rottlerin in vitro against Candida spp. and its toxicity and antifungal activity in vivo. Rottlerin showed antifungal activity against all yeasts evaluated, presenting Minimum Inhibitory and Fungicidal Concentration (MIC and MFC) values of 7.81 to > 1000 µg/mL. Futhermore, it was able to significantly inhibit biofilm production, presenting Biofilm Inhibitory Concentration (MICB50) values that ranged from 15.62 to 250 µg/mL and inhibition of the cell viability of the biofilm by 50% (IC50) from 2.24 to 12.76 µg/mL. There was a considerable reduction in all hydrolytic enzymes evaluated, with emphasis on hemolysin where Rottlerin showed a reduction of up to 20%. In the scanning electron microscopy (SEM) analysis, Rottlerin was able to completely inhibit filamentation by C. albicans. Regarding in vivo tests, Rottlerin did not demonstrate toxicity at the therapeutic concentrations demonstrated here and was able to increase the survival of C. elegans larvae infected. The results herein presented are innovative and pioneering in terms of Rottlerin's multipotentiality against these fungal infections.

2,2- dimethylbenzopyran derivatives containing pyridone structural fragments as selective dual-targeting inhibitors of HIF-1α and EZH2 for the treatment of lung cancer.

We formerly reported that EZH2 inhibitors sensitized HIF-1 inhibitor-resistant cells and inhibited HIF-1α to promote SUZ12 transcription, leading to enhanced EZH2 enzyme activity and elevated H3K27me3 levels, and conversely, inhibition of EZH2 promoted HIF-1α transcription. HIF-1α and EZH2 interacted to form a negative feedback loop that reinforced each other's activity. In this paper, a series of 2,2- dimethylbenzopyran derivatives containing pyridone structural fragments were designed and synthesized with DYB-03, a HIF-1α inhibitor previously reported by our group, and Tazemetostat, an EZH2 inhibitor approved by FDA, as lead compounds. Among these compounds, D-01 had significant inhibitory activities on HIF-1α and EZH2. In vitro experiments showed that D-01 significantly inhibited the migration of A549 cells, clone, invasion and angiogenesis. Moreover, D-01 had good pharmacokinetic profiles. All the results about compound D-01 could lay a foundation for the research and development of HIF-1α and EZH2 dual-targeting compounds.

Recent Advances and Outlook of Benzopyran Derivatives in the Discovery of Agricultural Chemicals.

Scaffold structures, new mechanisms of action, and targets present enormous challenges in the discovery of novel pesticides. The discovery of new scaffolds is the basis for the continuous development of modern agrochemicals. Identification of a good scaffold such as triazole, carbamate, methoxy acrylate, pyrazolamide, pyrido-pyrimidinone mesoionic, and bisamide often leads to the development of a new series of pesticides. In addition, pesticides with the same target, including the inhibitors of succinate dehydrogenase (SDH), oxysterol-binding-protein, and p-hydroxyphenyl pyruvate dioxygenase (HPPD), may have the same or similar scaffold structure. Recent years have witnessed significant progress in the discovery of new pesticides using natural products as scaffolds or bridges. In recent years, there have been increasing reports on the application of natural benzopyran compounds in the discovery of new pesticides, especially osthole and coumarin. A systematic and comprehensive review of benzopyran active compounds in the discovery of new agricultural chemicals is helpful to promote the discussion and development of benzopyran active compounds. Therefore, this work systematically reviewed the research and application of benzopyran derivatives in the discovery of agricultural chemicals, summarized the antiviral, herbicidal, antibacterial, fungicidal, insecticidal, nematicidal and acaricidal activities of benzopyran active compounds, and discussed the structural-activity relationship and mechanism of action. In addition, some active fragments were recommended to further optimize the chemical structure of benzopyran active compounds based on reference information.

Azaphilone pigments from the marine-derived Penicillium sclerotium UJNMF 0503 and their neuroprotective potential against H2O2-induced cell apoptosis through modulating PI3K/Akt pathway.

Azaphilones represent a particular group of fascinating pigments from fungal source, with easier industrialization and lower cost than the traditional plant-derived pigments, and they also display a wide range of pharmacological activities. Herein, 28 azaphilone analogs, including 12 new ones, were obtained from the fermentation culture of a marine fungus Penicillium sclerotium UJNMF 0503. Their structures were elucidated by MS, NMR and ECD analyses, together with NMR and ECD calculations and biogenetic considerations. Among them, compounds 1 and 2 feature an unusual natural benzo[d][1,3]dioxepine ring embedded with an orthoformate unit, while 3 and 4 represent the first azaphilone examples incorporating a novel rearranged 5/6 bicyclic core and a tetrahydropyran ring on the side chain, respectively. Our bioassays revealed that half of the isolates exhibited neuroprotective potential against H2O2-induced injury on RSC96 cells, while compound 13 displayed the best rescuing capacity toward the cell viability by blocking cellular apoptosis, which was likely achieved by upregulating the PI3K/Akt signaling pathway.

Synthesis, Antiproliferative Activity and Molecular Docking Analysis of Both Enantiomerically Pure Decursin Derivatives as Anticancer Agents.

Using (S)-decursinol isolated from root of Angelica gigas Nakai (AGN), we semi-synthesized and evaluated a series of both enantiomerically pure decursin derivatives for their antiproliferative activities against A549 human lung cancer cells. All synthesized compounds showed a broad spectrum of inhibitory activities against the growth of A549 cells. Especially, compound (S)-2d with (E)-(furan-3-yl)acryloyl group showed the most potent activity (IC50: 14.03 µM) against A549 cancer cells as compared with the reference compound, decursin (IC50: 43.55 µM) and its enantiomer, (R)-2d (IC50: 151.59 µM). Western blotting assays indicated that (S)-2d more strongly inhibited Janus kinase 1 (JAK1) and signal transducer and activator of transcription activation 3 (STAT3) phosphorylation than decursin in a dose-dependent manner, while having no effect on CXCR7 overexpression and total STAT3 level. In addition, (S)-2d induced cell cycle arrest at G1 phase and subsequent apoptotic cell death in A549 cancer cells. Our combined analysis of molecular docking studies and biological data suggests that the inhibition of JAK1 with (S)-2d resulted in loss of STAT3 phosphorylation and inhibition of cell growth in A549 cancer cells. These overall results strongly suggest that (S)-2d (MRC-D-004) as a novel JAK1 inhibitor may have therapeutic potential in the treatment of A549 human lung cancers by targeting the JAK1/STAT3 signaling pathway.

Synthesis, Characterization and Antimicrobial and Anticancer Evaluations of Some Novel Heteroannulated Difuro[3,2-c:3',2'-g]Chromenes.

The goal of this study was directed to synthesize a novel class of annulated compounds containing difuro[3,2-c:3',2'-g]chromene. Friedländer condensation of o-aminoacetyl derivative 3 was performed with some active methylene ketones, namely, 1,3-cyclohexanediones, pyrazolones, 1,3-thiazolidinones and barbituric acids, furnished furochromenofuroquinolines (4,5), furochromenofuropyrazolopyridines (6-8), furochromenofurothiazolopyridines (9,10) and furochromenofuropyridopyrimidines (11, 12), respectively. Also, condensation of substrate 3 with 5-amine-3-methyl-1H-pyrazole and 6-amino-1,3-dimethyluracil, as cyclic enamines, resulted in polyfused systems 13 and 14, respectively. In vitro antimicrobial efficiency of the prepared heterocycles against microbial strains exhibited variable inhibition action, where compound 3 was the most effective against all kinds of microorganisms. A significant cytotoxic activity was seen upon the annulation of the starting compound with thiazolopyridine (9 and 10) as well as pyridopyrimidine moieties (11, 12 and 14). The spectroscopic and analytical results were used to infer the structures of the novel synthesized compounds.

Neuroprotective azaphilones from a deep-sea derived fungus Penicillium sp. SCSIO41030.

Ten azaphilones including one pair of new epimers and three new ones, penineulones A-E (1-5) with the same structural core of angular deflectin, were obtained from a deep-sea derived Penicillium sp. SCSIO41030 fermented on a liquid medium. Their structures including absolute configurations were elucidated using chiral-phase HPLC analysis, extensive NMR spectroscopic and HRESIMS data, ECD and NMR calculations, and by comparing NMR data with literature data. Biological assays showed that the azaphilones possessed no antitumor and anti-viral (HSV-1/2) activities at concentrations of 5.0 µM and 20 µM, respectively. In addition, azaphilones 8 and 9 showed neuroprotective effects against Aß25-35-induced neurotoxicity in primary cultured cortical neurons at a concentration of 10 µM. Azaphilones 8 and 9 dramatically promoted axonal regrowth against Aß25-35-induced axonal atrophy. Our study indicated that azaphilones could be promising lead compounds for neuroprotection.

Bergenin attenuates triptolide-caused premature ovarian failure in mice based on the antioxidant activity.

Tripterygium wilfordii (TW) preparations have been utilized in China for treating rheumatoid arthritis and autoimmune diseases. However, their clinical use is limited due to reproductive toxicity, notably premature ovarian failure (POF). Our study aimed to investigate the effect and mechanism of bergenin in attenuating POF induced by triptolide in mice. POF was induced in female ICR mice via oral triptolide administration (50 µg/kg) for 60 days. Mice received bergenin (25, 50, 100 mg/kg, i.g.) or estradiol valerate (EV) (0.1 mg/kg, i.g.) daily, 1 h before triptolide treatment. In vitro, ovarian granulosa cells (OGCs) were exposed to triptolide (100 nM) and bergenin (1, 3, 10 µM). Antioxidant enzyme activity, protein expression, apoptosis rate, and reactive oxygen species (ROS) levels were assessed. The results showed that triptolide-treated mice exhibited evident atrophy, along with an increase in atretic follicles. Bergenin (50, 100 mg/kg) and EV (0.1 mg/kg), orally administered, exerted significant anti-POF effect. Bergenin and EV also decreased apoptosis in mouse ovaries. In vitro, bergenin (1, 3, 10 µM) attenuated triptolide-induced OGCs apoptosis by reducing levels of apoptosis-related proteins. Additionally, bergenin reduced oxidative stress through downregulation of antioxidant enzymes activity and overall ROS levels. Moreover, the combined use with Sh-Nrf2 resulted in a reduced protection of bergenin against triptolide-induced apoptosis of OGCs. Together, bergenin counteracts triptolide-caused POF in mice by inhibiting Nrf2-mediated oxidative stress and preventing OGC apoptosis. Combining bergenin with TW preparations may effectively reduce the risk of POF.

Bergenin potentiates BCG efficacy by enriching mycobacteria-specific adaptive memory responses via the Akt-Foxo-Stat4 axis.

The extensive inability of the BCG vaccine to produce long-term immune protection has not only accelerated the disease burden but also progressed towards the onset of drug resistance. In our previous study, we have reported the promising effects of Bergenin (Berg) in imparting significant protection as an adjunct immunomodulator against tuberculosis (TB). In congruence with our investigations, we delineated the impact of Berg on T cells, wherein it enhanced adaptive memory responses by modulating key transcription factors, STAT4 and Akt. We translated this finding into the vaccine model of TB and observed a notable reduction in the burden of Mycobacterium tuberculosis (M.tb) in BCG-Berg co-immunized mice as compared to BCG vaccination. Moreover, Berg, along with BCG, also aided in a heightened proinflammatory response milieu that corroborates the host protective immune response against TB. Furthermore, this response aligns with the escalated central and resident memory responses by modulating the Akt-Foxo-Stat4 axis, which plays a crucial role in enhancing the vaccine efficacy of BCG. These findings showcase the utilization of immunomodulator Berg as an immunoprophylactic agent to upgrade immunological memory, making it a more effective defender against TB.

The extracellular polymeric substances (EPS) accumulation of Spirulina platensis responding to Cadmium (Cd2+) exposure.

Spirulina platensis can secrete extracellular polymeric substances (EPS) helping to protect damage from stress environment, such as cadmium (Cd2+) exposure. However, the responding mechanism of S. platensis and the secreted EPS to exposure of Cd2+ is still unclear. This research focuses on the effects of Cd2+ on the composition and structure of the EPS and the response mechanism of EPS secretion from S. platensis for Cd2+ exposure. S. platensis can produce 261.37 mg·g-1 EPS when exposing to 20 mg·L-1 CdCl2, which was 2.5 times higher than the control group. The S. platensis EPS with and without Cd2+ treatment presented similar and stable irregularly fibrous structure. The monosaccharides composition of EPS in Cd2+ treated group are similar with control group but with different monosaccharides molar ratios, especially for Rha, Gal, Glc and Glc-UA. And the Cd2+ treatment resulted in a remarkable decline of humic acid and fulvic acid content. The antioxidant ability of S. platensis EPS increased significantly when exposed to 20 mg·L-1 CdCl2, which could be helpful for S. platensis protecting damage from high concentration of Cd2+. The transcriptome analysis showed that sulfur related metabolic pathways were up-regulated significantly, which promoted the synthesis of sulfur-containing amino acids and the secretion of large amounts of EPS.

Unlocking the Therapeutic Potential of Freshwater Sapropel Extracts: In Vitro Analysis and Antioxidant Profiling for Skincare Applications.

Background and Objective: Sapropel, a biologically active sedimentary deposit, is high in organic matter and minerals and has been shown to offer health benefits. Its constituents, humic acid (HA) and fulvic acid (FA), have been found to have some therapeutic applications. The aim of this study was to determine the potential therapeutically significant properties of freshwater sapropel extracts: their polyacid content, antioxidative (AO) status, and biological activity in cell culture. Materials and Methods: Freshwater lakes from the southeast region of Latvia were investigated layer by layer. The total organic carbon (TOC) was determined through combustion using the catalytic oxidation method, HA and FA were measured via acid perspiration, and the total polyphenol content (TPC) and total antioxidant status (TAS) was analysed spectrophotometrically. Sapropel extracts' regenerative abilities were tested in vitro using a Cell-IQ real-time monitoring system on mouse BALB/c 3T3 fibroblasts and human keratinocyte HaCaT cell lines. Cytotoxicity was measured through neutral red uptake assessment as a concentration-dependent reduction in the uptake of neutral red dye relative to a vehicle control or untreated cells. Results: The highest AO activity was observed in sapropel extracts with elevated concentrations of HA and TPC from Audzelu Lake (1.08 ± 0.03 mmol/L), and the lowest activity was found in extracts from Ivusku Lake (0.31 ± 0.01 mmol/L). Correspondingly, the concentrations of HA in Audzelu and Ivusku Lakes were recorded as 45.2 and 27.4 mg/g, respectively. High concentrations of HA promoted in vitro cell growth upon short-term exposure (up to 6 h). Conclusions: The results show that high TPC correlates with AO status and sapropel extracts with higher concentrations of HA exhibit greater AO activity and promote in vitro cell growth, suggesting a perspective use for short-term topical therapeutic skin applications. However, higher concentrations over longer durations showed cytotoxic effects, indicating the need for further investigation.

Synthesis of a new 2-prenylated quinoline as potential drug for metabolic syndrome with pan-PPAR activity and anti-inflammatory effects.

We have previously reported the total synthesis and structure-activity relationships (SAR) of 2-prenylated benzopyrans with PPAR agonist activity. Herein, we have described the synthesis and PPAR activity of 2-prenylated benzopyrans and 2-prenylated quinolines. The benzopyran nucleus was generated via enamine-catalyzed Kabbe condensation, and the quinoline nucleus via Friedländer condensation. Results demonstrated that both benzopyran (5a) and quinoline (4b) derivatives bearing a γ,δ-unsaturated ester displayed a pan-PPAR agonism. They were full PPARα agonists, but showed different preferences for PPARγ and PPARß/δ activation. It was noteworthy that quinoline 4b displayed full hPPARα activation (2-fold than WY-14,643), weak PPARß/δ and partial PPARγ activation. In addition, quinoline 4b showed anti-inflammatory effects on macrophages by reducing LPS-induced expression of both MCP-1 and IL-6. Therefore, 4b emerges as a first-in-class promising hit compound for the development of potential therapeutics aimed at treating metabolic syndrome, metabolic dysfunction-associated fatty liver disease (MAFLD), and its associated cardiovascular comorbidities.

Bergenin alleviates proliferative arterial diseases by modulating glucose metabolism in vascular smooth muscle cells.

BACKGROUND: Vascular smooth muscle cell (VSMC) proliferation and phenotypic switching are key mechanisms in the development of proliferative arterial diseases. Notably, reprogramming of the glucose metabolism pattern in VSMCs plays an important role in this process. PURPOSE: The aim of this study is to investigate the therapeutic potential and the mechanism underlying the effect of bergenin, an active compound found in Bergenia, in proliferative arterial diseases. METHODS: The effect of bergenin on proliferative arterial disease was evaluated using platelet-derived growth factor (PDGF)-stimulated VSMCs and a mouse model of carotid artery ligation. VSMC proliferation and phenotypic switching were evaluated in vitro using cell counting kit-8, 5-ethynyl-2-deoxyuridine incorporation, scratch, and transwell assays. Carotid artery neointimal hyperplasia was evaluated in vivo using hematoxylin and eosin staining and immunofluorescence. The expression of proliferation and VSMC contractile phenotype markers was evaluated using PCR and western blotting. RESULTS: Bergenin treatment inhibited PDGF-induced VSMC proliferation and phenotypic switching and reduced neointimal hyperplasia in the carotid artery ligation model. Additionally, bergenin partially reversed the PDGF-induced Warburg-like glucose metabolism pattern in VSMCs. RNA-sequencing data revealed that bergenin treatment significantly upregulated Ndufs2, an essential subunit of mitochondrial complex I. Ndufs2 knockdown attenuated the inhibitory effect of bergenin on PDGF-induced VSMC proliferation and phenotypic switching, and suppressed neointimal hyperplasia in vivo. Conversely, Ndufs2 overexpression enhanced the protective effect of bergenin. Moreover, Ndufs2 knockdown abrogated the effects of bergenin on the regulation of glucose metabolism in VSMCs. CONCLUSION: These findings suggest that bergenin is effective in alleviating proliferative arterial diseases. The reversal of the Warburg-like glucose metabolism pattern in VSMCs during proliferation and phenotypic switching may underlie this therapeutic mechanism.

Design and evaluation of nanostructured lipid carrier of Bergenin isolated from Pentaclethra macrophylla for anti-inflammatory effect on lipopolysaccharide-induced inflammatory responses in macrophages.

Herein, we report the properties of nanostructured lipid carriers (NLCs) prepared with a gradient concentration of Bergenin (BGN) isolated from Pentaclethra macrophylla stem bark powder. A gradient concentration of BGN (BGN 0, 50, 100, 150, and 200 mg) was prepared in a 5 % lipid matrix consisting of Transcutol HP (75 %), Phospholipon 90H (15 %), and Gelucire 43/01 (10 %) to which a surfactant aqueous phase consisting of Tween 80, sorbitol, and sorbic acid was dissolved. The NLCs were evaluated by size, polydispersity index (PDI), zeta potential, Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), encapsulation efficiency, and in vitro drug release. The result shows polydispersed nanoparticles with high drug encapsulation (94.26-99.50 %). The nanoparticles were mostly spherical, but those from the 50 mg BGN batch were more cuboidal than spherical. The drug release was highest from the latter to the tune of 40 % compared to the pure BGN solution, which released about 15 % BGN. The anti-inflammatory activity of the BGN-NLC and total plant extract was studied on lipopolysaccharide (LPS)-inflamed macrophages. The cell study showed that BGN and plant extract had low cytotoxicity on macrophages and exhibited a dose-dependent anti-inflammatory effect on the LPS-induced inflammatory process in macrophages.

Discovery of Strong 3-Nitro-2-Phenyl-2H-Chromene Analogues as Antitrypanosomal Agents and Inhibitors of Trypanosoma cruzi Glucokinase.

Chagas disease is one of the world's neglected tropical diseases, caused by the human pathogenic protozoan parasite Trypanosoma cruzi. There is currently a lack of effective and tolerable clinically available therapeutics to treat this life-threatening illness and the discovery of modern alternative options is an urgent matter. T. cruzi glucokinase (TcGlcK) is a potential drug target because its product, d-glucose-6-phosphate, serves as a key metabolite in the pentose phosphate pathway, glycolysis, and gluconeogenesis. In 2019, we identified a novel cluster of TcGlcK inhibitors that also exhibited anti-T. cruzi efficacy called the 3-nitro-2-phenyl-2H-chromene analogues. This was achieved by performing a target-based high-throughput screening (HTS) campaign of 13,040 compounds. The selection criteria were based on first determining which compounds strongly inhibited TcGlcK in a primary screen, followed by establishing on-target confirmed hits from a confirmatory assay. Compounds that exhibited notable in vitro trypanocidal activity over the T. cruzi infective form (trypomastigotes and intracellular amastigotes) co-cultured in NIH-3T3 mammalian host cells, as well as having revealed low NIH-3T3 cytotoxicity, were further considered. Compounds GLK2-003 and GLK2-004 were determined to inhibit TcGlcK quite well with IC50 values of 6.1 µM and 4.8 µM, respectively. Illuminated by these findings, we herein screened a small compound library consisting of thirteen commercially available 3-nitro-2-phenyl-2H-chromene analogues, two of which were GLK2-003 and GLK2-004 (compounds 1 and 9, respectively). Twelve of these compounds had a one-point change from the chemical structure of GLK2-003. The analogues were run through a similar primary screening and confirmatory assay protocol to our previous HTS campaign. Subsequently, three in vitro biological assays were performed where compounds were screened against (a) T. cruzi (Tulahuen strain) infective form co-cultured within NIH-3T3 cells, (b) T. brucei brucei (427 strain) bloodstream form, and (c) NIH-3T3 host cells alone. We report on the TcGlcK inhibitor constant determinations, mode of enzyme inhibition, in vitro antitrypanosomal IC50 determinations, and an assessment of structure-activity relationships. Our results reveal that the 3-nitro-2-phenyl-2H-chromene scaffold holds promise and can be further optimized for both Chagas disease and human African trypanosomiasis early-stage drug discovery research.

Brazilin-7-2-butenoate inhibits amyloid ß-protein aggregation, alleviates cytotoxicity, and protects Caenorhabditis elegans.

The fibrillogenesis of amyloid ß-protein (Aß) gradually accumulates to form neurotoxic Aß aggregates in the human brain, which is the direct cause of Alzheimer's disease (AD) related symptoms. There are currently no effective therapies for AD. Brazilin, a natural polyphenol, inhibits Aß fibrillogenesis, disrupts the mature fibrils and alleviates the corresponding cytotoxicity, but it also has the high toxic. Therefore, brazilin-7-2-butenoate (B-7-2-B), a brazilin derivative, was designed and synthesized. B-7-2-B exhibited lower toxicity and stronger inhibitory effect on Aß aggregation than brazilin. B-7-2-B could prevent the formation of Aß fibrils and oligomers, and depolymerize pre-formed aggregates in a dose-dependent manner. Furthermore, B-7-2-B prominently alleviated the cytotoxicity and the oxidative stress induced by Aß aggregates in PC12 cells. The protective impacts of B-7-2-B were further demonstrated by using the Caenorhabditis elegans model, including decreasing the extent of Aß aggregation, improving the motility and sensation disorders. Eventually, B-7-2-B was proven to be no apparent damage to worms. In summarize, it can be concluded that B-7-2-B has the potential as a drug for treating AD.

Activation of ERß hijacks the splicing machinery to trigger R-loop formation in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is a subtype of breast cancer with aggressive behavior and poor prognosis. Current therapeutic options available for TNBC patients are primarily chemotherapy. With our evolving understanding of this disease, novel targeted therapies, including poly ADP-ribose polymerase (PARP) inhibitors, antibody-drug conjugates, and immune-checkpoint inhibitors, have been developed for clinical use. Previous reports have demonstrated the essential role of estrogen receptor ß (ERß) in TNBC, but the detailed molecular mechanisms downstream ERß activation in TNBC are still far from elucidated. In this study, we demonstrated that a specific ERß agonist, LY500307, potently induces R-loop formation and DNA damage in TNBC cells. Subsequent interactome experiments indicated that the residues 151 to 165 of U2 small nuclear RNA auxiliary factor 1 (U2AF1) and the Trp439 and Lys443 of ERß were critical for the binding between U2AF1 and ERß. Combined RNA sequencing and ribosome sequencing analysis demonstrated that U2AF1-regulated downstream RNA splicing of 5-oxoprolinase (OPLAH) could affect its enzymatic activity and is essential for ERß-induced R-loop formation and DNA damage. In clinical samples including 115 patients from The Cancer Genome Atlas (TCGA) and 32 patients from an in-house cohort, we found a close correlation in the expression of ESR2 and U2AF1 in TNBC patients. Collectively, our study has unraveled the molecular mechanisms that explain the therapeutic effects of ERß activation in TNBC, which provides rationale for ERß activation-based single or combined therapy for patients with TNBC.