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501 result(s) for "Benzylisoquinolines"
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Safety and efficacy of oral administrated cepharanthine in non-hospitalized, asymptomatic or mild COVID-19 patients: a Double-blind, randomized, placebo-controlled trial
Cepharanthine (CEP) is a natural remedy that potently inhibits SARS-CoV-2 activity both in vitro and in vivo. To evaluate the efficacy and safety of CEP compared with placebo in adults with asymptomatic or mild coronavirus disease 2019 (COVID-19), we conducted a proof-of-concept, double-blind, randomized, placebo-controlled trial. Patients were randomized to receive 120 mg/day of CEP, 60 mg/day CEP or placebo for 5 days. Main outcome was the time from randomization to negative nasopharyngeal swab and safety. Among 262 randomized participants, 188 completed the trial among group of 120 mg/day CEP ( n  = 65), 60 mg/day CEP ( n  = 68) and placebo ( n  = 55). Neither 120 mg/day or 60 mg/day CEP shortened the time to negative significantly compared with placebo. However, 60 mg/day CEP showed a slight trend (difference=-0.77 days, hazard ratio (HR) = 1.40, 95% CI 0.97–2.01, p  = 0.072). In analysis of participants with good medication compliance, 60 mg/day CEP significantly shortened the time to negative (difference=-0.87 days, HR = 1.56, 95% CI 1.03–2.37, p  = 0.035). Adverse events were not different among the three groups, and no serious adverse events occurred. In conclusion, treatment of asymptomatic or mild Covid-19 with 120 mg/day or 60 mg/day did not shorten the time to negative significantly. However, 60 mg/day CEP showed a slight trend which needs future confirmatory trials to validate. (NCT05398705).
Development and evaluation of cepharanthine-β-cyclodextrin inclusion complex oral tablets for prevention and treatment of COVID-19 lung injury
The symptoms of coronavirus disease 2019 (COVID-19) range from severe lung disease to milder manifestations, such as cough and throat irritation. As a bisbenzylisoquinoline alkaloid, cepharanthine (CEP) has various pharmacological properties, such as antifibrotic, anti-inflammatory, antioxidant, and antiviral effects. However, its poor solubility and low bioavailability hinder subsequent drug development. Inclusion complex technology is a well-established drug delivery method that improves drug bioavailability. Therefore, in our study, we encapsulated CEP with β-cyclodextrin and formulated it into oral tablets. Oral tablets can be absorbed through sublingual and buccal mucosa, improving CEP bioavailability, facilitating convenient dosing, and thereby enhancing its therapeutic efficacy. The cepharanthine–β-cyclodextrin (CEP–β-CD) inclusion complex was prepared using the co-grinding method. It was characterized using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry to assess its physicochemical properties. Subsequently, the quality of the CEP–β-CD oral tablets was evaluated according to the relevant requirements of the 2020 edition of the Chinese Pharmacopoeia. Furthermore, the pharmacokinetic characteristics of the oral tablets were assessed in beagles. Finally, the anti-inflammatory effects of the CEP–β-CD oral tablets were evaluated in alveolar macrophage MH-S cells and a mouse pneumonia model. Our results suggest that the formulation of the CEP–β-CD inclusion complex into oral tablets is a promising preventive and therapeutic approach for lung injury caused by COVID-19.
Benzylisoquinoline alkaloid biosynthesis in opium poppy
Opium poppy (Papaver somniferum) is one of the world's oldest medicinal plants and remains the only commercial source for the narcotic analgesics morphine, codeine and semi-synthetic derivatives such as oxycodone and naltrexone. The plant also produces several other benzylisoquinoline alkaloids with potent pharmacological properties including the vasodilator papaverine, the cough suppressant and potential anticancer drug noscapine and the antimicrobial agent sanguinarine. Opium poppy has served as a model system to investigate the biosynthesis of benzylisoquinoline alkaloids in plants. The application of biochemical and functional genomics has resulted in a recent surge in the discovery of biosynthetic genes involved in the formation of major benzylisoquinoline alkaloids in opium poppy. The availability of extensive biochemical genetic tools and information pertaining to benzylisoquinoline alkaloid metabolism is facilitating the study of a wide range of phenomena including the structural biology of novel catalysts, the genomic organization of biosynthetic genes, the cellular and sub-cellular localization of biosynthetic enzymes and a variety of biotechnological applications. In this review, we highlight recent developments and summarize the frontiers of knowledge regarding the biochemistry, cellular biology and biotechnology of benzylisoquinoline alkaloid biosynthesis in opium poppy.
Computational planning of the synthesis of complex natural products
Training algorithms to computationally plan multistep organic syntheses has been a challenge for more than 50 years 1 – 7 . However, the field has progressed greatly since the development of early programs such as LHASA 1 , 7 , for which reaction choices at each step were made by human operators. Multiple software platforms 6 , 8 – 14 are now capable of completely autonomous planning. But these programs ‘think’ only one step at a time and have so far been limited to relatively simple targets, the syntheses of which could arguably be designed by human chemists within minutes, without the help of a computer. Furthermore, no algorithm has yet been able to design plausible routes to complex natural products, for which much more far-sighted, multistep planning is necessary 15 , 16 and closely related literature precedents cannot be relied on. Here we demonstrate that such computational synthesis planning is possible, provided that the program’s knowledge of organic chemistry and data-based artificial intelligence routines are augmented with causal relationships 17 , 18 , allowing it to ‘strategize’ over multiple synthetic steps. Using a Turing-like test administered to synthesis experts, we show that the routes designed by such a program are largely indistinguishable from those designed by humans. We also successfully validated three computer-designed syntheses of natural products in the laboratory. Taken together, these results indicate that expert-level automated synthetic planning is feasible, pending continued improvements to the reaction knowledge base and further code optimization. A synthetic route-planning algorithm, augmented with causal relationships that allow it to strategize over multiple steps, can design complex natural-product syntheses that are indistinguishable from those designed by human experts.
Tumor-Targeted cRGD-Coated Liposomes Encapsulating Optimized Synergistic Cepharanthine and IR783 for Chemotherapy and Photothermal Therapy
Combination therapy offers superior therapeutic results compared to monotherapy. However, the outcomes of combination therapy often fall short of expectations, mainly because of increased toxicity from drug interactions and challenges in achieving the desired spatial and temporal distribution of drug delivery. Optimizing synergistic drug combination ratios to ensure uniform targeting and distribution across space and time, particularly in vivo, is a significant challenge. In this study, cRGD-coated liposomes encapsulating optimized synergistic cepharanthine (CEP; a chemotherapy drug) and IR783 (a phototherapy agent) were developed for combined chemotherapy and photothermal therapy in vitro and in vivo. An MTT assay was used to evaluate the combination index of CEP and IR783 in five cell lines. The cRGD-encapsulated liposomes were prepared via thin-film hydration, and unencapsulated liposomes served as controls for the loading of CEP and IR783. Fluorescence and photothermal imaging were used to assess the efficacy of CEP and IR783 encapsulated in liposomes at an optimal synergistic ratio, both in vitro and in vivo. The combination indices of CEP and IR783 were determined in five cell lines. As a proof-of-concept, the optimal synergistic ratio (1:2) of CEP to IR783 in 4T1 cells was evaluated in vitro and in vivo. The average diameter of the liposomes was approximately 100 nm. The liposomes effectively retained the encapsulated CEP and IR783 in vitro at the optimal synergistic molar ratio for over 7 d. In vivo fluorescence imaging revealed that the fluorescence signal from cRGD-CEP-IR783-Lip was detectable at the tumor site at 4 h post-injection and peaked at 8 h. In vivo photothermal imaging of tumor-bearing mice indicated an increase in tumor temperature by 32°C within 200 s. Concurrently, cRGD-CEP-IR783-Lip demonstrated a significant therapeutic effect and robust biosafety in the in vivo antitumor experiments. The combination indices of CEP and IR783 were successfully determined in vitro in five cell lines. The cRGD-coated liposomes encapsulated CEP and IR783 at an optimal synergistic ratio, exhibiting enhanced antitumor effects and targeting upon application in vitro and in vivo. This study presents a novel concept and establishes a research framework for synergistic chemotherapy and phototherapy treatment.
Molecular mechanisms involved in drug-induced liver injury caused by urate-lowering Chinese herbs: A network pharmacology study and biology experiments
As an important part of the comprehensive treatment methods, the urate-lowering Chinese herbs could provide favorable clinical effects on hyperuricemia in its ability to invigorate spleen and remove dampness. Owing to the long-term duration, it brought up the potential adverse reactions (ADRs) and concerns about the drug-induced liver injury from these herbs. To address this problem, the bioinformatics approaches which combined the network pharmacology, computer simulation and molecular biology experiments were undertaken to elucidate the underlying drug-induced liver injury molecular mechanisms of urate-lowering Chinese herbs. Several electronic databases were searched to identify the potential liver injury compounds in published research. Then, the putative target profile of liver injury was predicted, and the interaction network was constructed based on the links between the compounds, corresponding targets and core pathways. Accordingly, the molecular docking simulation was performed to recognize the representative compounds with hepatotoxicity. Finally, the cell experiments were conducted to investigate the biochemical indicators and expression of the crucial protein that were closely associated with liver injury. In conclusion, the current research revealed that the compounds with potential liver injury including diosgenin, baicalin, saikosaponin D, tetrandrine, rutaecarpine and evodiamine from urate-lowering Chinese herbs, could lead to decline the survival rate of L-02 cell, increase the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) in cell-culture medium, enhance the expression of p-p38/p38, while the p38 inhibitor could achieve the trend of regulating and controlling liver injury. These research findings bring further support to the growing evidence that the mechanism of the liver injury induced by the compounds from urate-lowering Chinese herbs may be associated with the activation of p38α.
A Modular Chemoenzymatic Cascade Simplifies Divergent Synthesis of Natural and Unnatural Benzylisoquinoline Alkaloids
Conventional chemical or biological synthetic methods often encounter challenges in conveniently preparing chiral natural and unnatural products with the same skeleton at a scalable level, due to their complexity with numerous chiral centers or uncharacterized enzymes. Herein, a simplified modular chemoenzymatic platform is designed featuring a streamlined four‐enzyme cascade coupled with a chemical module that involves one or two chemical steps. This platform enables the divergent synthesis of structurally diverse natural and unnatural benzylisoquinoline alkaloids (BIAs), including 1‐benzylisoquinoline, protoberberine, morphinan, and aporphine alkaloids. Moreover, the enantioselectivity of the chiral BIAs is up to 99% ee. The titer of papaverine reaches an impressive 2.83 g L−1, demonstrating substantial industrial potential. Overall, this work establishes a paradigm for constructing modular chemoenzymatic platforms that simplify the production of structurally diverse natural and unnatural products for drug development. A simplified chemoenzymatic platform is designed to integrate an enzyme cascade with subsequent chemical steps, enabling the divergent production of diverse benzylisoquinoline alkaloids (BIAs). Demonstrating remarkable versatility and enantioselectivity, four distinct classes of BIAs are efficiently generated, in which the natural medicine papaverine is produced in the titer of 2.83 g L−1.
Cepharanthine inhibits hepatocellular carcinoma cell growth and proliferation by regulating amino acid metabolism and suppresses tumorigenesis in vivo
Cepharanthine (CEP), a natural compound extracted from Hayata, has been found to have the potential to treat a variety of tumors in recent years. This study aims to evaluate the anti-hepatocellular carcinoma (HCC) effect of CEP and determine its in-depth mechanism. In this study, Hep3B and HCCLM3 cells were selected to evaluate the antitumor effects of CEP , whereas tumor xenograft in nude mice was performed to make anti-tumor assessment. RNA-sequence (RNA-seq) was used to identify possible molecular targets and pathways. Further, gas chromatography mass spectrometry (GC-MS) was performed to assess the differential metabolites involved in mediating the effect of CEP on the HCC cell line. Our results showed that CEP treatment resulted in the dose-dependent inhibition of cell viability, migration, and proliferation and could also induce apoptosis in HCC cells. RNA-seq following CEP treatment identified 168 differentially expressed genes (DEGs), which were highly enriched in metabolism-associated pathways. In addition, CEP down-regulated many metabolites through the amino acid metabolism pathway. experiment showed that CEP significantly suppressed tumor growth. Our results indicate that CEP has significant antitumor effects and has the potential to be a candidate drug for HCC treatment.
Screening antiproliferative drug for breast cancer from bisbenzylisoquinoline alkaloid tetrandrine and fangchinoline derivatives by targeting BLM helicase
Background The high expression of BLM (Bloom syndrome) helicase in tumors involves its strong association with cell expansion. Bisbenzylisoquinoline alkaloids own an antitumor property and have developed as candidates for anticancer drugs. This paper aimed to screen potential antiproliferative small molecules from 12 small molecules (the derivatives of bisbenzylisoquinoline alkaloids tetrandrine and fangchinoline) by targeting BLM 642–1290 helicase. Then we explore the inhibitory mechanism of those small molecules on proliferation of MDA-MB-435 breast cancer cells. Methods Fluorescence polarization technique was used to screen small molecules which inhibited the DNA binding and unwinding of BLM 642–1290 helicase. The effects of positive small molecules on the ATPase and conformation of BLM 642–1290 helicase were studied by the malachite green-phosphate ammonium molybdate colorimetry and ultraviolet spectral scanning, respectively. The effects of positive small molecules on growth of MDA-MB-435 cells were studied by MTT method, colony formation and cell counting method. The mRNA and protein levels of BLM helicase in the MDA-MB-435 cells after positive small molecule treatments were examined by RT-PCR and ELISA, respectively. Results The compound HJNO (a tetrandrine derivative) was screened out which inhibited the DNA binding, unwinding and ATPase of BLM 642–1290 helicase. That HJNO could bind BLM 642–1290 helicase to change its conformationcontribute to inhibiting the DNA binding, ATPase and DNA unwinding of BLM 642–1290 helicase. In addition, HJNO showed its inhibiting the growth of MDA-MB-435 cells. The values of IC 50 after drug treatments for 24 h, 48 h and 72 h were 19.9 μmol/L, 4.1 μmol/L and 10.9 μmol/L, respectively. The mRNA and protein levels of BLM helicase in MDA-MB-435 cells increased after HJNO treatment. Those showed a significant difference ( P  < 0.05) compared with negative control when the concentrations of HJNO were 5 μmol/L and 10 μmol/L, which might contribute to HJNO inhibiting the DNA binding, ATPase and DNA unwinding of BLM helicase. Conclusion The small molecule HJNO was screened out by targeting BLM 642–1290 helicase. And it showed an inhibition on MDA-MB-435 breast cancer cells expansion.
Microbial Factories for the Production of Benzylisoquinoline Alkaloids
Benzylisoquinoline alkaloids (BIAs) are a family of ∼2500 alkaloids with both potential and realized pharmaceutical value, including most notably the opiates such as codeine and morphine. Only a few BIAs accumulate readily in plants, which limits the pharmaceutical potential of the family. Shifting BIA production to microbial sources could provide a scalable and flexible source of these compounds in the future. This review details the current status of microbial BIA synthesis and derivatization, including rapid developments in the past 6 months culminating in the synthesis of opioids from glucose in a microbial host. Both Escherichia coli and Saccharomyces cerevisiae have been engineered to convert a simple carbon source such as glucose to complex BIAs. The variety of BIA scaffolds synthesized in microbial hosts continues to increase, now encompassing benyliosquinolines, aporphines, protoberberines, protopines, benzophenanthridines, pro-morphinans, and morphinans. Key challenges for future work have been identified, including pathway bottlenecks and the generation of side-products from promiscuous enzymes.