Discovery of an EP300 Inhibitor using Structure-based Virtual Screening and Bioactivity Evaluation.

BACKGROUND: EP300 (E1A binding protein p300) played a significant role in serial diseases such as cancer, neurodegenerative disease. Therefore, it became a significant target. METHODS: Targeting EP300 discovery of a novel drug to alleviate these diseases. In this paper, 17 candidate compounds were obtained using a structure-based virtual screening approach, 4449-0460, with an IC50 of 5.89 ± 2.08 uM, which was identified by the EP300 bioactivity test. 4449-0460 consisted of three rings. The middle benzene ring connected the 5-ethylideneimidazolidine-2,4-dione group and the 3-F-Phenylmethoxy group. RESULTS: Furthermore, the interaction mechanism between 4449-0460 and EP300 was explored by combining molecular dynamics (MD) simulations and binding free energy calculation methods. CONCLUSION: The binding free energy of EP300 with 4449-0460 was -10.93 kcal/mol, and mainly came from the nonpolar energy term (ΔGnonpolar). Pro1074, Phe1075, Val1079, Leu1084, and Val1138 were the key residues in EP300/4449-0460 binding with more -1 kcal/mol energy contribution. 4449-0460 was a promising inhibitor targeting EP300, which had implications for the development of drugs for EP300-related diseases.

An integrated strategy for reducing anastomotic leakage in patients undergoing McKeown esophagectomy.

Objective: To describe our experience of reducing anastomotic leakage, a problem that has not been properly solved. Methods: Starting in January 2020, we began implementing our integrated strategy (application of an esophageal diameter-approximated slender gastric tube, preservation of the fibrous tissue around the residual esophagus and thyroid inferior pole anastomosis) in consecutive patients undergoing esophagectomy without a nasogastric tube or a nasal-jejunum feeding tube. Additionally, the blood supply at the site of the anastomosis was evaluated with a near-infrared fluorescence thoracoscope after the completion of esophagogastric anastomosis in the integrated strategy group. Results: Of 570 patients who were reviewed, 119 (20.9%) underwent the integrated strategy, and 451 (79.1%) underwent the conventional strategy. The rate of anastomotic leakage was 2.5% in the integrated strategy group and 10.2% in the conventional strategy group (p = 0.008). In the integrated strategy group, the site of most of the anastomotic blood supply was the residual esophagus dominant (82.4%), followed by the gastroesophageal dual-dominant (12.6%) and the gastric tube dominant (5.0%). The reconstruction route was more likely to be orthotopic in the integrated strategy group than in the conventional strategy group (89.9% vs. 38.6%, p = 0.004). Gastric dilation was identified in 3.4% of the patients in the integrated strategy group and in 21.1% in the conventional strategy group. Conclusions: Patients who underwent our proposed integrated strategy (Zhengzhou Strategy) during McKeown esophagectomy without a nasogastric tube or a nasal-jejunum feeding tube had a strikingly lower rate of anastomotic leakage and a relatively lower rate of postoperative complications, such as gastric tube dilation and delayed gastric emptying.

Management of esophageal cancer in patients with a right aortic arch or double aortic arch: a case series of 34 cases.

BACKGROUND: Few cases describing patients with a right aortic arch (RAA) or double aortic arch (DAA) and esophageal cancer (EC) have been reported. METHODS: We analyzed RAA and DAA cases treated with esophagectomy in our center's database and reported in English-language studies until April 1, 2023. Our study assessed the malformation characteristics and surgical details of EC patients with RAA and DAA. RESULTS: We extracted data of 24 EC patients with RAAs and 10 EC patients with DAAs. In both groups, the patients were more likely to be Japanese and male, to have squamous cell carcinoma and to have tumors located in the upper thoracic esophagus or middle thoracic esophagus. Left thoracotomy was commonly applied for RAA patients. For DAA patients, the proportions of left-sided and right-sided approaches were similar. Esophagectomy under video-assisted thoracoscopic surgery (VATS) in RAA or DAA patients had been performed on a routine basis in recent years. There were two anastomotic leakages in each group. Specifically, Kommerell diverticulum rupture occurred in 1 RAA patient; gastric tube dilation occurred in 1 DAA patient; and recurrent laryngeal nerve (RLN) injury occurred in 2 RAA patients. The postoperative course was uneventful for most patients in both cohorts. CONCLUSIONS: Esophageal carcinoma is rarely seen in patients with an RAA or DAA. To adequately dissect superior mediastinal LNs, an auxiliary incision (such as sternotomy), the left door open method or a preceding cervical procedure should be used appropriately. Esophagectomy, whether via thoracotomy or thoracoscopic surgery, can be performed safely for both RAA and DAA.

Catalytic Atroposelective Synthesis of Axially Chiral Azomethine Imines and Neuroprotective Activity Evaluation.

Azomethine imines, as a prominent class of 1,3-dipolar species, hold great significance and potential in organic and medicinal chemistry. However, the reported synthesis of centrally chiral azomethine imines relies on kinetic resolution, and the construction of axially chiral azomethine imines remains unexplored. Herein, we present the synthesis of axially chiral azomethine imines through copper- or chiral phosphoric acid catalyzed ring-closure reactions of N'-(2-alkynylbenzylidene)hydrazides, showcasing high efficiency, mild conditions, broad substrate scope, and excellent enantioselectivity. Furthermore, the biological evaluation revealed that the synthesized axially chiral azomethine imines effectively protect dorsal root ganglia (DRG) neurons by inhibiting apoptosis induced by oxaliplatin, offering a promising therapeutic approach for chemotherapy-induced peripheral neuropathy (CIPN). Remarkably, the (S)- and (R)-atropisomers displayed distinct neuroprotective activities, underscoring the significance of axial stereochemistry.

Eremophilane and cadinane sesquiterpenoids from the fruits of Alpinia oxyphylla and their anti-inflammatory activities.

The fruits of Alpinia oxyphylla have been used for centuries in China as both edible resources and traditional Chinese medicine. In order to identify structurally interesting and bioactive constituents from the fruits of A. oxyphylla, bioassay-guided fractionation and purification of the crude extracts were performed, which led to the isolation of 38 sesquiterpenoids, including six previously undescribed eremophilane sesquiterpenoids (1-6), six new cadinane sesquiterpenoids (23-24, 26-29), and 26 known analogues (7-22, 25 and 31-38). The structures of these compounds were elucidated by comprehensive spectroscopic data analysis, single crystal X-ray diffraction, quantum chemistry calculations (13C-NMR and ECD), and Mo2(OAc)4 reaction. Several of the isolated compounds (8, 13, 17, 18, 30, 31 and 35) showed moderate to strong inhibition of the secretion of cytokines (NO, TNF-α and IL-6) in LPS-stimulated BV-2 cells. Furthermore, western blot, immunofluorescence, and real-time PCR assays indicated that 18 could down-regulate the mRNA levels of TNF-α, IL-6, COX-2, and iNOS and the protein expression of COX-2 and iNOS. Meanwhile, 18 was able to partially inhibit the phosphorylation of ERK1/2, JNK, and p38. Thus, the discovery of structurally diverse anti-inflammatory sesquiterpenoids from the fruits of A. oxyphylla in this study could benefit the further development and utilization of this plant.

Two new diterpenoids from the rhizomes of Zingiber officinale.

Two undescribed labdane diterpenoids (5S,8S,9R,10S,11E)-8,17-epoxy-13,14-dinorlabd-11-en-13-one (1) and (5S,9R,10S,12E)-17-hydroxy-labd-7,12-dien-15(16)-olide (2), together with seven known sesquiterpenoids (3-9) and two known monoterpenoids (10-11) were isolated from the dried rhizome of Zingiber officinale. Their structures were elucidated by detailed spectroscopic data (IR, UV, HR-ESI-MS, 1D and 2D NMR), X-ray crystallographic and ECD analysis. Moreover, all the 11 compounds were tested for α-glucosidase inhibitory effects and 9 was found to exhibit stronger inhibitory effects at IC50 = 4.8 µM against a positive control acarbose with IC50 = 414.6 µM.

Antifibrotic pyridine-containing monoterpene alkaloids from Caryopteris glutinosa.

Three undescribed dimeric pyridine-containing alkaloids, caryopterisines C - E, and four unreported cyclopenta[c]pyridine-derived alkaloids, caryopterisines F - I, were identified from Caryopteris glutinosa Rehder (Lamiaceae), together with two known monoterpene alkaloids. Caryopterisine C, featuring with an unprecedented 6/5/6/6/5 pentacyclic rings scaffold, may biosynthetically stem from a Diels-Alder reaction of two cyclopenta[c]pyridine-containing monomers and a following aromatization rearrangement reaction. Caryopterisines D and E, possessing an unprecedented 6/6/6/6/5 fused rings framework, may originate from a same Diels-Alder reaction of two monomers and subsequent aromatization arrangement, Baeyer-Villiger oxidation, and a set of tailoring reactions. Caryopterisine C showed strong inhibition on collagen accumulation in NIH3T3 cells (IC50 = 14.26 ± 1.46 µM). Caryopterisines G and I reduce collagen accumulation with IC50 values 88.91 ± 0.95 µM and 33.09 ± 1.38 µM, respectively. The Western blotting of the transforming growth factor-ß-activated signaling pathways revealed that caryopterisine C inhibits collagen expression and accumulation via suppression of the phosphorylation of ERK1/2, P38, and SMAD2/3. The present works indicate caryopterisine C is a potential lead compound for the development of antifibrotic drugs.

Identifying the molecular basis of Jinhong tablets against chronic superficial gastritis via chemical profile identification and symptom-guided network pharmacology analysis.

Chronic superficial gastritis (CSG) is a common disease of the digestive system that possesses a serious pathogenesis. Jinhong tablet (JHT), a traditional Chinese medicine (TCM) prescription, exerts therapeutic effects against CSG. However, the molecular basis of its therapeutic effect has not been clarified. Herein, we employed ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q/TOF-MS) based chemical profile identification to determine the chemical components in JHT. Further, we applied network pharmacology to illustrate its molecular mechanisms. A total of 96 chemical constituents were identified in JHT, 31 of which were confirmed using reference standards. Based on the bioinformatics analysis using the symptom-guided pharmacological networks of "chi," "blood," "pain," and "inflammation," and target screening through the interaction probabilities between compounds and targets, matrix metalloproteinase 2 (MMP2), dopamine d2 receptor (DRD2), and Aldo-keto reductase family 1 member B1 (AKR1B1) were identified as key targets in the therapeutic effect exhibited by JHT against CSG. Moreover, according to the inhibitory activities presented in the literature and binding mode analysis, the structural types of alkaloids, flavonoids, organic acids, including chlorogenic acid (10), caffeic acid (13), (-)-corydalmine (33), (-)-isocorypalmine (36), isochlorogenic acid C (38), isochlorogenic acid A (41), quercetin-3-O-α-l-rhamnoside (42), isochlorogenic acid B (47), quercetin (63), and kaempferol (70) tended to show remarkable activities against CSG. Owing to the above findings, we systematically identified the chemical components of JHT and revealed its molecular mechanisms based on the symptoms associated with CSG.

Rheumatoid arthritis drug sinomenine induces apoptosis of cervical tumor cells by targeting thioredoxin reductase in vitro and in vivo.

Overexpression of thioredoxin reductase (TrxR) has been linked to tumorigenesis and phenotypic maintenance of malignant tumors. Thus, targeting TrxR with natural molecules is a promising strategy for developing anticancer drugs. Sinomenine is a naturally occurring alkaloid isolated from Sinomenium acutum. The drug, Zhengqing Fengtongning made from sinomenine, has been universally applied in rheumatoid arthritis treatment in China as well as other Asian countries for decades. Recently, increasing evidence indicates that sinomenine appears to be a promising therapeutic agent against various cancer cells. However, the exact mechanism underlying the anticancer activity of sinomenine remains unclear. In this study, we identified sinomenine as a kind of new inhibitor for TrxR. Pharmacological inhibition of TrxR by sinomenine results in the decrease of thiols content, increases the levels of reactive oxygen species, and finally facilitates oxidative stress-mediated cancer cell apoptosis. It is vital that knockdown in TrxR1 by shRNA can increase cell sensitivity to sinomenine. Treatment with sinomenine in vivo leads to a decrease in TrxR activity and tumor growth, and an increase in apoptosis. Our findings provide a novel action mechanism related to sinomenine and presents an insight on how to develop sinomenine as a chemotherapeutic agent for cancer therapy.

Oridonin Induces Oxidative Stress-mediated Cancer Cells Apoptosis via Targeting Thioredoxin Reductase.

BACKGROUND: Thioredoxin reductase (TrxR) plays vital role in regulating cellular redox balance as well as redox-mediated signal transduction. Accumulating evidence supports that overactivation of TrxR is closely related to tumorigenesis and that targeting TrxR ablation reverses the growth of numerous malignant tumors, making TrxR a promising target for cancer chemotherapy. Thus, the discovery and development of molecules as promising anticancer agents that target TrxR is of great significance. Oridonin was shown to inhibit TrxR activity, but the detailed cellular mechanism is largely unknown. OBJECTIVE: The study investigated the mechanism of action and underlying inhibitory properties of oridonin on TrxR in HeLa cells. METHODS: A covalent docking was performed to reveal the possible interaction between oridonin and TrxR by Schrödinger Software Suite. TrxR activity was determined by 5,5'-dithiobis-2- nitrobenzoic acid reduction assay and endpoint insulin reduction assay. Sulforhodamine B and colony formation assay were employed to assess the viability and growth of cells. Reactive oxygen species level was measured by probe 2', 7'-dichlorfluorescein diacetate, and dihydroethidium. Hoechst 33342 staining, caspase 3 activation, and fluorescein-5-isothiocyanate-conjugated Annexin V and propidium iodide double staining were used to evaluate apoptosis. RESULTS: Here, we reported the oridonin as a potent inhibitor of TrxR. Inhibition of TrxR results in a decrease of thiols content and total glutathione, elevates reactive oxygen species levels, and finally promotes oxidative stress-mediated apoptosis of cancer cells. CONCLUSION: Targeting TrxR by oridonin discloses a novel molecular mechanism underlying the biological action of oridonin and sheds light on developing oridonin as a potential tumor therapeutic agent.

(±)-Caryopterisines A and B, dimeric monoterpene alkaloids with unprecedented 6/5/5/5/6 pentacyclic rings scaffold from Caryopteris glutinosa.

(±)-Caryopterisines A (1) and B (2) featuring an unprecedented 6/5/5/5/6 pentacyclic rings system were isolated from Caryopteris glutinosa. The structures were determined by spectroscopic and X-ray crystallographic data analyses as well as theoretical calculations. Chiral HPLC resolution of both racemic 1 and 2 afforded their corresponding enantiotropic enantiomers. A plausible biogenesis for 1 and 2 may be originated from Diels-Alder reaction between pyridine-containing oxerine derivatives. The enantiotropic conversion mechanism of the enantiomers was demonstrated by H-D exchange and 18O incorporation studies. Compounds 1 and 2 showed moderate inhibition of estrogen E2 biosynthesis in human ovarian granulosa-like KGN cells. These two alkaloids reduced kynurenine biosynthesis at moderate level via inhibition of indoleamine 2,3-dioxygenase. Alkaloid 2 exhibited moderate inhibition of the release of interleukin-1ß.

Targeting thioredoxin reductase by deoxyelephantopin from Elephantopus scaber triggers cancer cell apoptosis.

Elevated expression of thioredoxin reductase (TrxR) is associated with the tumorigenesis and resistance to cancer chemoradiotherapy, highlighting the potential of TrxR inhibitors as anticancer drugs. Deoxyelephantopin (DET) is the major active ingredient of Elephantopus scaber and reveals potent anticancer activity. However, the potential mechanism of action and the cellular target of DET are still unknown. Here, we found that DET primarily targets the Sec residue of TrxR and irreversibly prohibits enzyme activity. Suppression of TrxR by DET leads to accumulation of reactive oxygen species and dysregulation in intracellular redox balance, eventually inducing cancer cell apoptosis mediated by oxidative stress. Noticeably, down-regulation of TrxR1 by shRNA increases cell sensitivity to DET. Collectively, targeting of TrxR1 by DET uncovers a novel mechanism of action in DET and deepens the understanding of developing DET as a potential chemotherapeutic agent for treating cancers.

Discovery of pentapeptide-inhibitor hits targeting FKBP51 by combining computational modeling and X-ray crystallography.

FKBP51 is well-known as a cochaperone of Hsp90 machinery and implicated in many human diseases including stress-related diseases, tau-mediated neurodegeneration and cancers, which makes FKBP51 an attractive drug target for the therapy of FKBP51-associated diseases. However, it has been reported that only nature product rapamycin, cyclosporine A, FK506 and its derivatives exhibit good binding affinities when bound to FKBP51 by now. Given the advantages of peptide-inhibitors, we designed and obtained 20 peptide-inhibitor hits through structure-based drug design. We further characterized the interaction modes of the peptide-inhibitor hits on the FK1 domain of FKBP51 by biochemical and structural biology methods. Structural analysis revealed that peptide-inhibitor hits form U-shaped conformations and occupy the FK506 binding pocket and share similar interaction modes with FK506. Using molecular dynamics simulations, we delved into the interaction dynamics and found that hits are anchored to the FK506 binding pocket in a quite stable conformation. Meanwhile, it was shown that interactions between FK1 and peptide-inhibitor hits are mainly attributed to the hydrogen bond networks comprising I87 and Y113 and FPF cores of peptide-inhibitors involved extensive hydrophobic interactions. We presumed that the peptide design strategy based on the small molecule structure probably shed new lights on the peptide-inhibitor discovery of other targets. The findings presented here could also serve as a structural basis and starting point facilitating the optimization and generation of FKBP51 peptide-inhibitors with better bio-activities.

A new nitrogen-containing iridoid glycoside from lonicera macranthoides.

A new nitrogen-containing iridoid glycoside, named (7 R,3'R)-lonijapospiroside A (1), together with thirteen known iridoid glycosides, were isolated from the flower buds of Lonicera macranthoides. The structures of these compounds were established on the basis of spectroscopic analyses. Among them, compounds 1-4 are four diastereoisomers, and their absolute configurations were accurately established by the NOE spectra as well as comparison of their experimental and calculated ECD spectra. The anti-inflammatory activities of all isolates were evaluated by measuring their inhibitory effects on NO, IL-6, and TNF-α production in LPS stimulated RAW 264.7 macrophages. Compound 14 exhibited anti-inflammatory activities by inhibiting IL-6 with an IC50 value of 54.70 µM, comparable to that of the positive control (hydrocortisone, IC50: 62.6 ± 1.7 µM).

Three new cycloart-7-ene triterpenoid glycosides from Cimicifuga dahurica and their anti-inflammatory effects.

Ten cycloart-7-ene triterpenoid glycosides, including three new compounds (1-3), were isolated from the roots of Cimicifuga dahurica. Their structures were elucidated on the basis of extensive spectroscopic analyses, chemical methods and comparison with literatures. In addition, the isolates were evaluated for their inhibitory effects on the production of NO, as well as the expressions of iNOS and COX-2 in LPS-stimulated RAW 264.7 macrophages. The results showed that compounds 3, 5, 6, 7 and 8 can reduce the release of NO in a dose-dependent manner. Mechanistically, Western blot analysis indicated that the NO inhibitory effects relied on down-regulating the expression of iNOS, and partially associated with lowering the expression of COX-2.

Diarylheptanoid analogues from the rhizomes of Zingiber officinale and their anti-tumour activity.

Eight previously undescribed diarylheptanoids (1-8), together with fifteen known analogues (9-23), were isolated from the rhizomes of Zingiber officinale. Their structures were unambiguously determined by comprehensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. It is worth mentioning that 1-3 are the first reported structures of diaryl ether heptanoids in Z. officinale, whereas 15-17 were isolated from Zingiber for the first time. Furthermore, a gene enrichment analysis of the interacting targets indicated that diarylheptanoids were mainly associated with the anti-tumor activity by affecting DNA damage signaling pathway. The results showed that 6, 16-19 had remarkable inhibitory effects against five tumor cell lines (A549, HepG2, HeLa, MDA-MB-231, and HCT116) with IC50 values ranging from 6.69-33.46 µM, and showed down-regulating the expression of ATR (ataxia telangiectasia mutated and RAD3-related) and CHK1 (checkpoint kinase 1) levels in HCT116 and A549 cell lines. Our studies not only enrich the structural diversity of diarylheptanoids in nature, but also discover several natural compounds for anti-tumor agents.

Structurally diverse sesquiterpenoids from the aerial parts of Artemisia annua (Qinghao) and their striking systemically anti-inflammatory activities.

Thirteen new sesquiterpenoids, arteannoides F-R (1-13), along with 13 known analogues (14-26), were isolated from the dried aerial parts of Artemisia annua L. Their structures, including absolute configurations, were unambiguously determined by a combination of physical data analyses (HRESIMS, 1D and 2D NMR, and ECD) as well as the crystal structures of 1, 5, 6, 15, 19, and 23. Among the isolated compounds, 1 features an unusual 11-oxatricyclo[6.2.1.04,9]undecan-2-ene ring system, 5 possesses an uncommon 4,11-ether bridged tricyclic framework, whereas 6 is a new eudesmane-type sesquiterpenoid formed via rearrangement of its carbon backbone. The systemically anti-inflammatory activities of all isolates were evaluated by measuring their inhibitory effects on PGE2, NO, TNF-α, and IL-6 production in LPS-stimulated RAW 264.7 macrophages. Moreover, the structure activity relationships of some compounds are summarized, this study will provide new structural templates for discovering potential anti-inflammatory agents.

Discovery of novel ATAD2 bromodomain inhibitors that trigger apoptosis and autophagy in breast cells by structure-based virtual screening.

ATAD2 has been reported to play an important role in the processes of numerous cancers and validated to be a potential therapeutic target. This work is to discover potent ATAD2 inhibitors and elucidate the underlying mechanisms in breast cancer. A novel ATAD2 bromodomain inhibitor (AM879) was discovered by combining structure-based virtual screening with biochemical analyses. AM879 presents potent inhibitory activity towards ATAD2 bromodomain (IC50 = 3565 nM), presenting no inhibitory activity against BRD2-4. Moreover, AM879 inhibited MDA-MB-231 cells proliferation with IC50 value of 2.43 µM, suppressed the expression of c-Myc, and induced significant apoptosis. Additionally, AM978 could induce autophagy via PI3K-AKT-mTOR signalling in MDA-MB-231 cells. This study demonstrates the development of potent ATAD2 inhibitors with novel scaffolds for breast cancer therapy.

Design, synthesis and biological evaluation of 1H-pyrazolo [3,4-d]pyrimidine derivatives as PAK1 inhibitors that trigger apoptosis, ER stress and anti-migration effect in MDA-MB-231 cells.

P21-activated kinase 1 (PAK1) is associated with cell proliferation, survival and migration. Deregulation of PAK1 activity is involved in various human diseases, including cancer, inflammation, and neurological disorders. Using a high-throughput virtual screening, we identified the 1H-pyrazolo [3,4-d]pyrimidine scaffold as a promising lead for targeting PAK1. We designed and synthesized a focused library through a structure-based strategy. A novel potent PAK1 inhibitor, ZMF-10, was discovered, which presented an IC50 value of 174 nM with a good selectivity. In addition, ZMF-10 could inhibit PAK1-ERK signaling to suppress MDA-MB-231 cells proliferation with an IC50 value of 3.48 µM for 48 h. Subsequently, ZMF-10 was documented to induce cell apoptosis. Interestingly, according to the RNASeq-based analyses, we substantiated that ZMF-10 induced significant ER-Stress, suppressed migration via FOXO3 activation, JNK1/2, ERK1/2 and AKT signaling inhibition. Together, these results demonstrate that ZMF-10 is a novel PAK1 inhibitor triggering apoptosis, ER stress and anti-migration effect in MDA-MB-231 cells, which may provide a candidate lead for the development of novel potent inhibitors of PAK1.