ABSTRACT
The severe acute respiratory syndrome coronavirus (SARS-CoV-2) pandemic has triggered a significant impact on global public health security, it is urgent to develop effective antiviral drugs. Previous studies have found that binding to ACE2 is a key step in the invasion of SARS-CoV-2 into host cells, so virus invasion can be inhibited by blocking ACE2, but there are few reports on this kind of specific inhibitor. Our previous study found that Harringtonine (HT) can inhibit the entry of SARS-CoV-2 spike pseudovirus into ACE2h cells, but its relatively high cytotoxicity limits its further development. Amino acid modification of the active components can increase their solubility and reduce their cytotoxicity. Therefore, in this study, seven new derivatives were synthesized by amino acid modification of its core structure Cephalotaxine. The target compounds were evaluated by cell viability assay and the SARS-CoV-2 spike pseudovirus entry assay. Compound CET-1 significantly inhibited the entry of pseudovirus into ACE2h cells and showed less cytotoxicity than HT. Molecular docking results showed that CET-1 could bind TYR83, an important residue of ACE2, just like HT. In conclusion, our study provided a novel compound with more potential activity and lower toxicity than HT on inhibiting the SARS-CoV-2 spike pseudovirus infection, which makes it possible to be a lead compound as an antiviral drug in the future.
Subject(s)
Angiotensin-Converting Enzyme 2 , Antiviral Agents , COVID-19 Drug Treatment , Homoharringtonine , Molecular Docking Simulation , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Humans , Amino Acids/chemistry , Amino Acids/pharmacology , Angiotensin-Converting Enzyme 2/metabolism , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/chemical synthesis , Cell Survival/drug effects , COVID-19/virology , Homoharringtonine/pharmacology , Homoharringtonine/chemistry , SARS-CoV-2/drug effects , Spike Glycoprotein, Coronavirus/metabolism , Spike Glycoprotein, Coronavirus/antagonists & inhibitors , Spike Glycoprotein, Coronavirus/chemistry , Virus Internalization/drug effects , Harringtonines/chemistry , Harringtonines/pharmacologySubject(s)
Alkaloids , Harringtonines , Neoplasms , Humans , Harringtonines/pharmacology , Alkaloids/pharmacology , Neoplasms/drug therapyABSTRACT
Harringtonine (HT) is an anticancer alkaloid early extracted and isolated from cephalotaxus fortunei Hook. f., also has various pharmacological activities such as antiviral, antibacterial, antimalarial, anti-inflammatory, antioxidant, herbicidal and insecticidal. However, the factors affecting the stability of HT, the main degradation sites and mechanisms involved in its disposal process in vivo have not yet been elucidated. This study utilized HPLC-fluorescence detection method to establish a simple quantitative detection method for HT with good accuracy, precision, and high sensitivity. Temperature and pH were the main factors affecting the stability of HT, which underwent significant degradation in high temperature and alkaline environments because of the occurrence of hydrolysis reactions. In isolated biological homogenates of SD rats, except gastrointestinal tract, HT was degraded in other sites, especially respiratory, mainly in airway and lungs, and systemic metabolism, mainly in livers, spleens, and kidneys. Through UPLC-Q-TOF-MS, three forced degradation products were identified as 4'-demethyl HT, cephalotaxine, and dehydrated HT, respectively. However, the degradation product in isolated biological homogenates of SD rats was only 4'-demethyl HT due to the relatively mild environment. Our findings contributed to a necessary study basis for HT in terms of structural optimization, dosage form selection, storage and transportation.
Subject(s)
Antineoplastic Agents , Harringtonines , Rats , Animals , Chromatography, High Pressure Liquid/methods , Rats, Sprague-Dawley , Harringtonines/chemistry , Homoharringtonine/chemistryABSTRACT
Fortuneicyclidins A and B are a pair of recently isolated Cephalotaxus alkaloids with an unprecedented rearranged polycyclic skeleton possessing multiple complex stereocenters and functionalization. In this work, highly stereocontrolled asymmetric total syntheses for title alkaloids were outlined. Key features include an underexplored Ir-catalyzed α-allylation of aldehyde to strategically install a vicinal N-substituted quaternary center and a tertiary stereocenter, Heck and RCM reactions to construct the critical polycyclic framework rapidly, two different tandem oxidation-transannular aldol cyclization processes, one through ozonolysis and another via Swern oxidation, to forge the last ring for fortuneicyclidins A and B, respectively. In this approach, the challenging C-2 hydroxyl group can be installed stereospecifically.
Subject(s)
Alkaloids , Harringtonines , Stereoisomerism , Cyclization , Oxidation-ReductionABSTRACT
To compare efficacy between homoharringtonine combined with cytarabine and aclarubicin (HAA) and idarubicin and cytarabine (IA) regimens as first induction chemotherapy in patients with core binding factor acute myeloid leukemia (CBF-AML). Cox regression model and propensity score matching (PSM) were used to identify the regimen associated with a better remission rate and outcomes. In total, 374 patients with CBF-AML (243 with RUNX1::RUXN1T1 and 131 with CBFB::MYH11) were included in this study. The patients received the HAA or IA regimen (187 each) as the first induction therapy. For patients with RUNX1::RUXN1T1, multivariate analyses showed that the HAA regimen was significantly associated with a higher CR/CRi rate after the first induction (hazard ratio [HR] = 5.3 [95% CI 2.3, 12.2]; p < 0.001) and more favorable relapse-free survival (RFS) (HR = 0.5 [0.3, 0.8], p = 0.01). In PSM analysis, the HAA regimen also had a higher CR/CRi rate (96% vs. 77%, p < 0.001), especially for those harboring wild-type KIT (KITWT) (96% vs. 83%, p = 0.02) or non-D816 KIT mutation (100% vs. 63%, p = 0.002), as well as more favorable RFS (p = 0.01), compared with the IA regimen. However, there was no difference in the remission rate or outcomes between the two regimens for patients with CBFB::MYH11. The HAA regimen as first induction chemotherapy resulted in a higher CR/CRi rate in AML patients with RUNX1::RUNX1T1, especially those harboring KITWT and non-D816 KIT mutation, and a more favorable RFS compared with the IA regimen. The efficacy between the two regimens did not differ in those with CBFB::MYH11.
Subject(s)
Harringtonines , Leukemia, Myeloid, Acute , Humans , Idarubicin/therapeutic use , Homoharringtonine , Core Binding Factor Alpha 2 Subunit/genetics , Cytarabine/therapeutic use , Aclarubicin , Induction Chemotherapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Remission InductionABSTRACT
Modified nucleotides are ubiquitous with RNAs, also in contact with drugs that target the ribosome. Whether this represents a stabilization of the drug-ribosome complex, thus affecting the drug's affinity and possibly also intrinsic efficacy, remains an open question, however. The challenge of answering this question has been taken here with the only human-ribosome-targeting small-molecule currently in clinical use, the antitumor plant alkaloid homoharringtonine (HHT). The approach consisted in dissecting HHT-nucleotide interaction energies from QM-MM simulations in explicit water. What emerged is a network of mostly weak interactions of the large, branched HHT with standard nucleotides and a single modified nucleotide, out of the four ones present at PCT's A site. This is unlike the case of the small, compact marine antitumor alkaloid agelastatin A, which displays only a few, albeit strong, interactions with site-A ribosome nucleotides. This should aid tailoring drugs targeting the ribosome.
Subject(s)
Antineoplastic Agents, Phytogenic , Antineoplastic Agents , Harringtonines , Humans , Homoharringtonine , Harringtonines/pharmacology , Nucleotides , Antineoplastic Agents/pharmacology , RibosomesABSTRACT
Fusion with host cell membrane is the main mechanism of infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we propose that a new strategy to screen small-molecule antagonists blocking SARS-CoV-2 membrane fusion. Using cell membrane chromatography (CMC), we found that harringtonine (HT) simultaneously targeted SARS-CoV-2 S protein and host cell surface TMPRSS2 expressed by the host cell, and subsequently confirmed that HT can inhibit membrane fusion. HT effectively blocked SARS-CoV-2 original strain entry with the IC50 of 0.217 µM, while the IC50 in delta variant decreased to 0.101 µM, the IC50 in Omicron BA.1 variant was 0.042 µM. Due to high transmissibility and immune escape, Omicron subvariant BA.5 has become the dominant strain of the SARS-CoV-2 virus and led to escalating COVID-19 cases, however, against BA.5, HT showed a surprising effectiveness. The IC50 in Omicron BA.5 was even lower than 0.0019 µM. The above results revealed the effect of HT on Omicron is very significant. In summary, we characterize HT as a small-molecule antagonist by direct targeting on the Spike protein and TMPRSS2.
Subject(s)
COVID-19 , Harringtonines , Humans , SARS-CoV-2ABSTRACT
The Complexity-to-Diversity (CtD) strategy was applied to synthesize a 23-member compound collection from the natural product drupacine, including 21 novel compounds. An unusual benzo [d] cyclopenta [b] azepin skeleton was constructed by Von Braun reaction to cleave C-N bond of drupacine. Moreover, compound 10 has potential cytotoxicity to human colon cancer cells with low toxicity to the normal human colon mucosal epithelial cell lines.
Subject(s)
Biological Products , Colonic Neoplasms , Harringtonines , Humans , Biological Products/pharmacology , Harringtonines/chemistry , Cell LineABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has recently posed a serious threat to global public health. Harringtonine (HT), as a small-molecule antagonist, has antiviral activity against a variety of viruses. There is evidence that HT can inhibit the SARS-CoV-2 entry into host cells by blocking the Spike protein and transmembrane protease serine 2 (TMPRSS2). However, the molecular mechanism underlying the inhibition effect of HT is largely elusive. Here, docking and all-atom molecular dynamics simulations were used to investigate the mechanism of HT against the receptor binding domain (RBD) of Spike, TMPRSS2, as well as the complex of RBD and angiotensin-converting enzyme 2 complex (RBD-ACE2). The results reveal that HT binds to all proteins primarily through hydrogen bond and hydrophobic interactions. Binding with HT influences the structural stability and dynamic motility processes of each protein. The interactions of HT with residues N33, H34 and K353 of ACE2, and residue K417 and Y453 of RBD contribute to disrupting the binding affinity between RBD and ACE2, which may hinder the virus entry into host cells. Our research provides molecular insights into the inhibition mechanism of HT against SARS-CoV-2 associated proteins, which will help for the novel antiviral drugs development.
Subject(s)
COVID-19 , Harringtonines , Humans , SARS-CoV-2 , Angiotensin-Converting Enzyme 2 , Protein Binding , Molecular Dynamics Simulation , Molecular Docking SimulationABSTRACT
Cephalotaxine-type alkaloids (CTAs), represented by homoharringtonine (HHT, 1), display potent efficacy against different types of leukemia cells. In this study, a method for hydrogenation of ß-substituted itaconic acid monoesters with chiral Ru[DTBM-SegPhos](OAc)2 was developed. This metal-catalyzed asymmetric hydrogenation enabled the convenient semisynthesis of novel cephalotaxine derivatives with chiral 2'-substituted-succinic acid 4-mono-methyl esters as side chains. The preliminary structure-activity relationship (SAR) of the compounds' antineoplastic activities was studied. Eventually, we discovered compound 10b with potent antineoplastic activities against leukemia and broadly anticancer activities against a panel of cancer cells. Our study provided a highly enantioselective process enabling the semisynthesis of cephalotaxine derivatives, which are interesting for further study on a scientific basis.
Subject(s)
Antineoplastic Agents , Harringtonines , Leukemia , Humans , Homoharringtonine/pharmacology , Esters/pharmacology , Esters/chemistry , Stereoisomerism , Harringtonines/pharmacology , Harringtonines/chemistry , Antineoplastic Agents/pharmacologyABSTRACT
Hainanolide (HN) is a norditerpenoid metabolite extract from Cephalotaxus fortunei Hook. f. C. fortunei Hook. f. is renowned for the active alkaloids, such as harringtonine (HT) and homoharringtonin (HTT), which have been clinically used to treat chronic myeloid leukemia. Nowadays, diterpenoids, another important metabolite, attracted the attention of chemists. Among them, Hainanolide (HN), a cephalotane-type diterpenoid, has been proven to possess potent antitumor activities. However, the underlying therapeutic mechanisms of HN in anti-tumor have not been investigated yet. Our present study demonstrated that HN inhibited HCT-116 and HCT-15 cell proliferation in a dose- and time-dependent manner. Further studies demonstrated that HN can induce G2/M phase arrest and alter the Cdc25C/Cdc2/CyclinB1 proteins. Western blot indicated that HN promoted apoptosis by up-regulating Bax and down-regulated Bcl-2. And the caspase-3 and caspase-9 activities of HCT-116 and HCT-15 cells were increased. Transcriptome analysis is used to reveal the possible mechanism. Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses suggested the genes were mainly enriched in the MAPK signaling pathway. Certainly, HN activates MAPK signaling pathway. In vivo, HN prevented the AOM/DSS-induced tumorigenesis of colon cancer in C57BL/6 mice. Our study indicated that HN inhibits the progression of colon cancer cells by blocking the cell cycle, inducing apoptosis, and activating the MAPK pathway. This study provides a theoretical and experimental scientific basis for future investigations of the antitumor effects of HN against colon cancer.
Subject(s)
Colonic Neoplasms , Diterpenes , Harringtonines , Animals , Apoptosis , Caspase 3/metabolism , Caspase 9/metabolism , Cell Cycle , Cell Cycle Checkpoints , Cell Line, Tumor , Cell Proliferation , Colonic Neoplasms/metabolism , Diterpenes/pharmacology , Diterpenes/therapeutic use , Harringtonines/pharmacology , Harringtonines/therapeutic use , Mice , Mice, Inbred C57BL , Proto-Oncogene Proteins c-bcl-2/metabolism , Signal Transduction , bcl-2-Associated X Protein/metabolismABSTRACT
Silica gel, octadecyl-silica(ODS), Sephadex LH-20, and semi-preparative high performance liquid chromatography(HPLC) was performed to isolate nine cephalotaxine-type alkaloids from Cephalotaxus sinensis: 8-oxodeoxyharringtonine(1), 8-oxonordeoxyharringtonine(2), cephafortunine A(3), 8-oxocephalotaxine(4), deoxyharringtonine(5), acetylcephalotaxine(6), cephalotaxine(7), epicephalotaxine(8), and cephalotaxinone(9). Compounds 1 and 2 were identified for the first time and their structures were determined by high-resolution-electrospray ionization-mass spectrometry(HR-ESI-MS), nuclear magnetic resonance(NMR), and electronic circular dichroism(ECD). Compounds 1-3 and 5 significantly inhibited the transcription of nuclear factor kappa B(NF-κB), with the half-maximal inhibitory concentration(IC_(50)) of(3.91±0.70),(2.99±0.45),(7.84±0.51), and(1.46±0.17) µmol·L~(-1), respectively.
Subject(s)
Cephalotaxus , Harringtonines , Cephalotaxus/chemistry , Chromatography, High Pressure Liquid , Harringtonines/chemistry , Harringtonines/pharmacology , Homoharringtonine , Spectrometry, Mass, Electrospray IonizationABSTRACT
Six undescribed isoquinoline alkaloids, named as cephaloliverines A-F, were isolated from the seeds of Cephalotaxus oliveri. They were identified by NMR and MS spectroscopic data analyses, combined with the time-dependent density functional theory ECD calculation for cephaloliverines A and B and also by X-ray crystal diffraction for cephaloliverine E. Biosynthetic considerations suggest that cephaloliverines A-D are homologous of cephalotaxine-, homoerythrina- and Erythrina-type alkaloids. The performed bioassay revealed no cytotoxic activity against cancer cells and no neuroprotective properties on HEI-OC-1 cells model.
Subject(s)
Alkaloids , Cephalotaxus , Harringtonines , Alkaloids/chemistry , Alkaloids/pharmacology , Cephalotaxus/chemistry , Harringtonines/pharmacology , Homoharringtonine , SeedsABSTRACT
Harringtonine (HT), produced from Cephalotaxus species, is known to exhibit potent antiproliferative activity against myeloid leukemia cells by inhibiting protein synthesis. A previous study using acute promyelocytic leukemia (HL-60) cells raised the possibility that the C-5' methyl group of HT plays an important role in regulating leukemia cell line antiproliferative activity. In order to investigate the effect of hydrocarbon chains at C-5' on the resultant activity, the C-5' methyl group was replaced with various straight- and branched-chain hydrocarbons using the corresponding alcohols, and their antiproliferative activity against HL-60 and HeLa cells was investigated. As a result, 4'-n-heptyl-4'-demethylharringtonine (1f, n-heptyl derivative) showed the most potent cytotoxicity among the HT ester derivatives produced, with IC50 values of 9.4 nM and 0.4 µM for HL-60 and HeLa cells, respectively. Interestingly, the cytotoxicity of derivative 1f against HL-60 and HeLa cells respectively was â¼5 (IC50 = 50.5 nM) and â¼10 times (IC50 = 4.0 µM) those of HT and â¼2 (IC50 = 21.8 nM) and â¼4 times (IC50 = 1.7 µM) more than homoharringtonine (HHT). These results demonstrate the potential of the derivative 1f as a lead compound against leukemia.
Subject(s)
Harringtonines , Leukemia, Promyelocytic, Acute , Esters/pharmacology , HL-60 Cells , Harringtonines/pharmacology , HeLa Cells , HumansABSTRACT
Eight cephalotaxine-type alkaloids (1-8), including two new compounds cephafortunines A and B (1-2), were isolated from the branches and leaves of Cephalotaxus fortunei var. alpina. Their structures were identified by a series of spectroscopic methods (MS, UV, IR, 1D, and 2D NMR) and comparison with the reported data of known analogs. The absolute configurations of 1 and 2 were determined by electronic circular dichroism (ECD) calculations. 1-8 were evaluated for their in vitro antiproliferation effects against two human leukemia cell lines (U937 and HL-60). All compounds showed different levels of antiproliferation effects against U937 cells with GI50 values of 4.21-23.70 µM. 4 and 5 were the most active against U937 cells with GI50 values of 4.21 and 6.58 µM and against HL-60 cells with GI50 values of 6.66 and 6.70 µM, respectively. 4 and 5 arrested HL-60 cell cycle in G0/G1 phase.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cephalotaxus/chemistry , Harringtonines/pharmacology , Antineoplastic Agents, Phytogenic/isolation & purification , China , HL-60 Cells , Harringtonines/isolation & purification , Humans , Molecular Structure , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Plant Leaves/chemistry , U937 CellsABSTRACT
Six new Cephalotaxus alkaloids, including five cephalotaxine-type alkaloids, and one homoerythrina-type alkaloid, along with six known analogues, were isolated from the seeds of Cephalotaxus fortunei. Their structures were elucidated by combination of spectroscopic data analyses, time-dependent density functional theory (TDDFT) ECD calculation, and single-crystal X-ray diffraction. Cephalofortine B represents the first example of C-5 epi-cephalotaxine-type alkaloid. All isolated compounds were tested for cytotoxicities against HCT-116, A375, and SK-Mel-28 cell lines. Cephalofortine E showed moderate activity against HCT-116 cell line, with an IC50 value of 7.46 ± 0.77 µM.
Subject(s)
Alkaloids , Antineoplastic Agents, Phytogenic , Cephalotaxus , Harringtonines , Alkaloids/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Harringtonines/pharmacology , Homoharringtonine , Humans , Molecular Structure , SeedsABSTRACT
Harringtonolide (HO), a natural product isolated from Cephalotaxus harringtonia, exhibits potent antiproliferative activity. However, little information has been reported on the systematic structure-activity relationship (SAR) of HO derivatives. Modifications on tropone, lactone, and allyl positions of HO (1) were carried out to provide 17 derivatives (2-13, 11a-11f). The in vitro antiproliferative activity against four cancer cell lines (HCT-116, A375, A549, and Huh-7) and one normal cell line (L-02) was tested. Amongst these novel derivatives, compound 6 exhibited comparable cell growth inhibitory activity to HO and displayed better selectivity index (SI = 56.5) between Huh-7 and L-02 cells. The SAR results revealed that the tropone and lactone moieties are essential for the cytotoxic activities, which provided useful suggestions for further structural optimization of HO.
Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Cell Proliferation , Harringtonines/chemistry , Neoplasms/drug therapy , Dose-Response Relationship, Drug , Drug Design , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Structure-Activity RelationshipABSTRACT
While numerous studies pertaining to the total synthesis of Cephalotaxus alkaloids have been reported, only two strategies have been reported to date for the successful synthesis of the C-11 oxygenated subset, due to the additional synthetic challenge posed by the remote C-11 stereocenter. Herein, we report the collective asymmetric total synthesis of C-11 oxygenated Cephalotaxus alkaloids using a chiral proline both as a starting material and as the only chirality source. A tetracyclic advanced intermediate was synthesized in a highly stereoselective manner from l-proline in 8 steps involving sequential chirality transfer steps such as a diastereoselective N-alkylation, stereospecific Stevens rearrangement and intramolecular Friedel-Crafts reaction via an unusual O-acyloxocarbenium intermediate. From a common intermediate, the asymmetric total synthesis of six C-11 oxygenated Cephalotaxus alkaloids was completed by a series of oxidation state adjustments.
Subject(s)
Harringtonines/chemical synthesis , Alkylation , Cyclization , Molecular Structure , Oxidation-Reduction , Proline/chemistry , StereoisomerismABSTRACT
There has been a surge of interest towards targeting protein synthesis to treat diseases and extend lifespan. Despite the progress, few options are available to assess translation in live animals, as their complexity limits the repertoire of experimental tools to monitor and manipulate processes within organs and individual cells. It this study, we developed a labeling-free method for measuring organ- and cell-type-specific translation elongation rates in vivo. It is based on time-resolved delivery of translation initiation and elongation inhibitors in live animals followed by ribosome profiling. It also reports translation initiation sites in an organ-specific manner. Using this method, we found that the elongation rates differ more than 50% among mouse organs and determined them to be 6.8, 5.0 and 4.3 amino acids per second for liver, kidney, and skeletal muscle, respectively. We further found that the elongation rate is reduced by 20% between young adulthood and mid-life. Thus, translation, a major metabolic process in cells, is tightly regulated at the level of elongation of nascent polypeptide chains.