Morphinane alkaloid dimers from Sinomenium acutum

Cytotoxic activities of alkaloid constituents from the climbing stems and rhizomes of Sinomenium acutum against cancer stem cells

From the methanolic extract of the climbing stems and rhizomes of Sinomenium acutum, two new aporphine analogues, acutumalkaloids I and II, were isolated together with fifteen known compounds including lysicamine. The chemical structures of the isolated new compounds were elucidated based on chemical/physicochemical evidence such as NMR and MS spectra. For acutumalkaloids I and II, the absolute configurations were established by comparison of experimental and predicted electronic circular dichroism (ECD) data. We compared anti-proliferative activities of isolated compounds with reported naturally occurring Wnt/β-catenin pathway inhibitor, nuciferine. Among the isolated compounds, we found lysicamine have anti-proliferative activity against both of HT-29 human colon cancer cell line and its cancer stem cells (CSCs). The IC50 values of lysicamine against non-CSCs and its CSCs were lower than that of nuciferine. In addition, the results of western blotting analysis suggested that lysicamine inhibited the expression of Wnt/β-catenin pathway target protein such as survivin. These results suggested that lysicamine show cytotoxic activity via inhibition of Wnt/β-catenin pathway.

Chemistry and biology of ent-morphinan alkaloids

Morphinan alkaloids have attracted constant attention since the isolation of morphine by Sertürner in 1805. However, a group of 45 compounds possessing a complete ent-morphinan backbone can also be found in the literature. These compounds are related to the morphinandienone subgroup and display a substitution pattern which is different from the morphinans. In particular, these alkaloids could be substituted at position C-2 and C-8 either by a hydroxy function or a methoxy moiety. Four groups of ent-morphinan alkaloids can be proposed, the salutaridine, pallidine, cephasugine and erromangine series. Interestingly, the botanical distribution of the ent-morphinans is more widespread than for the morphinans and includes the Annonaceae, Berberidaceae, Euphorbiaceae, Fumariaceae, Hernandiaceae, Lauraceae, Menispermaceae, Monimiaceae, Papaveraceae, and Ranunculaceae families. To date, their exact mode of production remains elusive and their interplay with the biosynthetic pathway of other classes of benzyltetrahydroisoquinoline alkaloids, in particular aporphines, should be confirmed. Exploration of the biological and therapeutic potential of these compounds is limited to some areas, namely central nervous system (CNS), inflammation, cancer, malaria and viruses. Further studies should be conducted to identify the cellular/molecular targets in view of promoting these compounds as new scaffolds in medicinal chemistry.

Full-length transcriptome and metabolite analysis reveal reticuline epimerase-independent pathways for benzylisoquinoline alkaloids biosynthesis in Sinomenium acutum

Benzylisoquinoline alkaloids (BIAs) are a large family of plant natural products with important pharmaceutical applications. Sinomenium acutum is a medicinal plant from the Menispermaceae family and has been used to treat rheumatoid arthritis for hundreds of years. Sinomenium acutum contains more than 50 BIAs, and sinomenine is a representative BIA from this plant. Sinomenine was found to have preventive and curative effects on opioid dependence. Despite the broad applications of S. acutum, investigation on the biosynthetic pathways of BIAs from S. acutum is limited. In this study, we comprehensively analyzed the transcriptome data and BIAs in the root, stem, leaf, and seed of S. acutum. Metabolic analysis showed a noticeable difference in BIA contents in different tissues. Based on the study of the full-length transcriptome, differentially expressed genes, and weighted gene co-expression network, we proposed the biosynthetic pathways for a few BIAs from S. acutum, such as sinomenine, magnoflorine, and tetrahydropalmatine, and screened candidate genes involved in these biosynthesis processes. Notably, the reticuline epimerase (REPI/STORR), which converts (S)-reticuline to (R)-reticuline and plays an essential role in morphine and codeine biosynthesis, was not found in the transcriptome data of S. acutum. Our results shed light on the biogenesis of the BIAs in S. acutum and may pave the way for the future development of this important medicinal plant.

Identification and quality control strategy of impurities in Zhengqing Fengtongning injection

Zhengqing Fengtongning injection is the sterile aqueous solution of Sinomenine Hydrochloride extracted from the root and stem of Sinomenium acutum, and is widely used to treat rheumatoid arthritis. Due to the processes of extraction, separation, purification, preparation and storage, some related impurities might be formed, which may cause side effects on patients. It is important to rapidly separate and identify the related impurities to ensure the safe use of Zhengqing Fengtongning injection. However, there are few literatures about the impurity in Zhengqing Fengtongning injection. In this work, ultra-high performance liquid chromatography- quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) was developed to analyze impurities in both Zhengqing Fengtongning injection and its drug substance, with Sinomenine Hydrochloride as its active pharmaceutical ingredient (API). Six impurities of the Zhengqing Fengtongning injection were found. Structures of impurities 1 and 6 were confirmed by NMR and other impurities were identified from the fragmentation pattern of Sinomenine, the similarity of molecular weight and fragment ions in references. Finally, the HPLC analytical technique was developed to achieve the quantification of impurities 1 and 6. In addition, some reasonable suggestions are put forward on the quality control of Zhengqing Fengtongning injection and its drug substance based on the processes and structural characteristics of the related substances. The technical system established in this paper is helpful to strengthen the quality control of Zhengqing Fengtongning injection and improve production, and can also provide references for the production and quality control of similar drugs.

An Apriori Algorithm-Based Association Analysis of Analgesic Drugs in Chinese Medicine Prescriptions Recorded From Patients With Rheumatoid Arthritis Pain

Chronic pain, a common symptom of people with rheumatoid arthritis, usually behaves as persistent polyarthralgia pain and causes serious damage to patients' physical and mental health. Opioid analgesics can lead to a series of side effects like drug tolerance and addiction. Thus, seeking an alternative therapy and screening out the corresponding analgesic drugs is the key to solving the current dilemma. Traditional Chinese Medicine (TCM) therapy has been recognized internationally for its unique guiding theory and definite curative effect. In this study, we used the Apriori Algorithm to screen out potential analgesics from 311 cases that were treated with compounded medication prescription and collected from “Second Affiliated Hospital of Zhejiang Chinese Medical University” in Hangzhou, China. Data on 18 kinds of clinical symptoms and 16 kinds of Chinese herbs were extracted based on this data mining. We also found 17 association rules and screened out four potential analgesic drugs—“Jinyinhua,” “Wugong,” “Yiyiren,” and “Qingfengteng,” which were promised to help in the clinical treatment. Besides, combined with System Cluster Analysis, we provided several different herbal combinations for clinical references.

Sinomenium acutum: A Comprehensive Review of its Botany, Phytochemistry, Pharmacology and Clinical Application

Sinomenium acutumis the dry stem of Sinomenium acutum (Thunb.) Rehd et Wils. (S. acutum) and Sinomenium acutum(Thunb.) Rehd. et Wils. var. cinereumRehd. et Wils and is mainly distributed in China and Japan. As a traditional Chinese medicine (TCM) for dispelling wind and dampness in China, it is widely distributed and has a long history of drug use. In recent years, with the increase of the incidence of rheumatoid disease, S. acutum has become the focus of research. This paper reviews the literature on the chemical constituents, pharmacological effects, clinical applications and pharmacokinetics and safety of S. acutum from the past 60 years. At present, more than 210 natural compounds have been isolated from S. acutum, including alkaloids, lignans, triterpenoid saponins, steroids, and other structures. Pharmacological activities of S. acutum were mainly reported on anti-inflammatory, analgesic, anti-allergic, immunosuppressive, anti-tumor, liver-protective, anti-oxidative, and other effects, and clinical applications were mainly recorded on rheumatoid arthritis, ankylosing spondylitis, and other diseases. The clinical use of SIN has fewer side effects and more safety; only a small number of gastrointestinal reactions occurred, and the symptoms disappeared after the drug stopped. The purpose of this paper is to lay a foundation and provide reference for the follow-up research and wide application of S. acutum.

Liquid Chromatography Coupled with Linear Ion Trap Hybrid OrbitrapMass Spectrometry for Determination of Alkaloids in Sinomeniumacutum

The characterization of alkaloids is challenging because of the diversity of structures and the complicated fragmentation of collision induced structural dissociation in mass spectrometry. In this study, we analyzed the alkaloids in Sinomenium acutum (Thunb.) Rehderet Wil by high resolution mass spectrometry. Chromatographic separation was achieved on a Phenomenex Kinetex C18 (2.1 mm × 100 mm, 2.6 μm) column with a mobile phase consisting of acetonitrile and water (0.1% formic acid) under gradient elution. A total of 52 alkaloids were well separated and 45 of them were structurally characterized, including morphinans, aporphines, benzylisoquinolines, and protoberberines. Specially, mass spectrometric study of the morphinan alkaloids were explicitly investigated. Electrostatic potential plot from simulation was calculated for determination of protonation sites. Further fragmentation analysis suggested that the C₃H₇N, CH₄O, and H₂O elimination was displayed in MS² spectrum. These fragmentation pathways are universal for morphinan alkaloids having methoxy substituted cyclohexenone or cyclohexadienone moieties. Additionally, for nitrogen oxides, an ion-neutral complex intermediate is involved in the fragmentation process, generating additional oxygenated ions. All these results provided the universal rules of fragmentation used for detection of alkaloids, and will be expected to be highly useful for comprehensive study of multi-components in the herbal medicine analysis.

Sinomenine, an Alkaloid Derived from Sinomenium acutum Potentiates Pentobarbital-Induced Sleep Behaviors and Non-Rapid Eye Movement (NREM) Sleep in Rodents

Sinomenium acutum has been long used in the preparations of traditional medicine in Japan, China and Korea for the treatment of various disorders including rheumatism, fever, pulmonary diseases and mood disorders. Recently, it was reported that Sinomenium acutum, has sedative and anxiolytic effects mediated by GABA-ergic systems. These experiments were performed to investigate whether sinomenine (SIN), an alkaloid derived from Sinomenium acutum enhances pentobarbital-induced sleep via γ-aminobutyric acid (GABA)-ergic systems, and modulates sleep architecture in mice. Oral administration of SIN (40 mg/kg) markedly reduced spontaneous locomotor activity, similar to diazepam (a benzodiazepine agonist) in mice. SIN shortened sleep latency, and increased total sleep time in a dose-dependent manner when co-administrated with pentobarbital (42 mg/kg, i.p.). SIN also increased the number of sleeping mice and total sleep time by concomitant administration with the sub-hypnotic dosage of pentobarbital (28 mg/kg, i.p.). SIN reduced the number of sleep-wake cycles, and increased total sleep time and non-rapid eye movement (NREM) sleep. In addition, SIN also increased chloride influx in the primary cultured hypothalamic neuronal cells. Furthermore, protein overexpression of glutamic acid decarboxylase (GAD_65/67) and GABA_A receptor subunits by western blot were found, being activated by SIN. In conclusion, SIN augments pentobarbital-induced sleeping behaviors through GABA_A-ergic systems, and increased NREM sleep. It could be a candidate for the treatment of insomnia.

Regulation of miRNAs by herbal medicine: An emerging field in cancer therapies

MicroRNAs' expression profiles have recently gained major attention as far as cancer research is concerned. MicroRNAs are able to inhibit target gene expression via binding to the 3' UTR of target mRNA, resulting in target mRNA cleavage or translation inhibition. MicroRNAs play significant parts in a myriad of biological processes; studies have proven, on the other hand, that aberrant microRNA expression is, more often than not, associated with the growth and progression of cancers. MicroRNAs could act as oncogenes (oncomir) or tumor suppressors and can also be utilized as biomarkers for diagnosis, prognosis, and cancer therapy. Recent studies have shown that such herbal extracts as Shikonin, Sinomenium acutum, curcumin, Olea europaea, ginseng, and Coptidis Rhizoma could alter microRNA expression profiles through inhibiting cancer cell development, activating the apoptosis pathway, or increasing the efficacy of conventional cancer therapeutics. Such findings patently suggest that the novel specific targeting of microRNAs by herbal extracts could complete the restriction of tumors by killing the cancerous cells so as to recover survival results in patients diagnosed with malignancies. In this review, we summarized the current research about microRNA biogenesis, microRNAs in cancer, herbal compounds with anti-cancer effects and novel strategies for employing herbal extracts in order to target microRNAs for a better treatment of patients diagnosed with cancer.

Screening and identification of Caulis Sinomenii bioactive ingredients with dual-target NF-κB inhibition and β2- AR agonizing activities

Caulis Sinomenii (CS) is a valuable traditional medicine in China. Its extract can act as an anti-inflammatory agent and a vascular smooth muscle relaxant. However, the underlying mechanisms remain unknown. In this study, we developed a simple dual-target method based on ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry combined with a dual-target bioactive screening assay for anti-inflammatory and antispasmodic activities to characterize the chemical structure of various bioactive compounds of CS rapidly. Seven potential NF-κB inhibitors were identified, including laudanosoline-1-O-xylopyranose, 6-O-methyl-laudanosoline-1-O-glucopyranoside, menisperine, sinomenine, laurifoline, magnoflorine and norsinoacutin. Furthermore, IL-6 and IL-8 assays confirmed the anti-inflammatory effects of these potential NF-κB inhibitors, in which laudanosoline-1-O-d-xylopyranose and menisperine were revealed as novel NF-κB inhibitors. Among the seven identified alkaloids, three potential β₂ -adrenergic receptor agonists, including sinomenine, magnoflorine and laurifoline, were characterized using a luciferase reporter system to measure for the activity of β₂ -adrenergic receptor agonists. Finally, sinomenine, magnoflorine and laurifoline were identified not only as potential NF-κB inhibitors but also as potential β₂ -adrenegic receptor agonists, which is the first time this has been reported. Molecular dynamic simulation and docking results suggest that the three dual-bioactive constituents could not only inhibit Pseudomonas aeruginosa PAK strain-induced inflammatory responses via a negative regulation of the Braf protein that participates in MAPK signaling pathway but also activate the β₂ -adrenegic receptor. These results suggest that CS extract has dual signaling activities with potential clinical application as a novel drug for asthma.

Identification of nuclear factor-κB inhibitors in the folk herb Rhizoma Menispermi via bioactivity-based ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry analysis

BACKGROUND

Rhizoma Menispermi (RM) is the dried root of Menispermum dauricum DC, which is traditionally used to treat swelling and pain for sore throat, enteritis and rheumatic arthralgia in the clinic, but its bioactive compounds remain unclear.

METHODS

In this study, RM extract was administered orally to ICR mice followed by challenging with an intratracheal Pseudomonas aeruginosa suspension. Then mortality, histological features of lung, and inflammatory cytokines were evaluated. RM treatment significantly ameliorated Pseudomonas aeruginosa-induced acute lung inflammation and reduced levels of inflammatory mediators. To screen for potential anti-inflammatory constituents of the RM extract, a simple and rapid method based on ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF MS) coupled with a luciferase reporter assay system to detect nuclear factor-κB (NF-κB) activity was established.

RESULTS

Using this system, seven potential NF-κB inhibitors were detected, including sinomenine, norsinoacutin, N-norsinoacutin-β-D-glucopyranoside, 6-O-methyl-laudanosoline-13-O-glucopyranoside, magnoflorine, laurifloline and dauricinoline. Furthermore, IL-6 and IL-8 assays confirmed the anti-inflammatory effects of these potential NF-κB inhibitors, in which norsinoacutin, 6-O-methyl-laudanosoline-13-O-glucopyranoside laurifloline, dauricinoline and N-norsinoacutin-β-D-glucopyranoside were revealed as new NF-κB inhibitors.

CONCLUSION

This method of UPLC-Q/TOF coupled with the luciferase reporter assay system was initially applied to the study of RM and was demonstrated to represent a simple, rapid and practical approach to screen for anti-inflammatory compounds. This study provided useful results for further investigation on the anti-inflammatory mechanism of RM.

Comparative pharmacokinetics study of sinomenine in rats after oral administration of sinomenine monomer and Sinomenium acutum extract

Various products containing sinomenine monomer and extracts of Sinomenium acutum have been widely applied in clinical treatments. The goal of the present study was to compare the pharmacokinetics of sinomenine in rats after oral administration of sinomenine monomer and Sinomenium acutum extract, and to attempt to explore potential component-component interactions between the constituents of this traditional Chinese herbal medicine. A reliable and specific reversed phase high performance liquid chromatography method was developed to analyze sinomenine in rat plasma. Pharmacokinetic parameters for sinomenine were processed by non-compartmental analysis. The results showed that the maximum concentration, the area under the concentration-time curve, clearance and the apparent volume of distribution of sinomenine in the Sinomenium acutum extract statistically differed from those of sinomenine monomer (p < 0.05); however, the mean residence time, time of peak concentration, and half-life did not show significant differences between the two groups. These findings suggested that some additional components in the Sinomenium acutum extract may decrease the absorption of sinomenine. The complex interactions between sinomenine and other components of the herbal extract could result in the altered pharmacokinetic behavior of sinomenine, which may subsequently cause different therapeutic and detoxification effects.

Sinomenine hydrochloride enhancement of the inhibitory effects of anti-transferrin receptor antibody-dependent on the COX-2 pathway in human hepatoma cells

Transferrin receptor (TfR) has been used as a target for the antibody-based therapy of cancer due to its higher expression in tumors relative to normal tissues. Great potential has been shown by anti-TfR antibodies combined with chemotherapeutic drugs as a possible cancer therapeutic strategy. In our study, we investigated the anti-tumor effects of anti-TfR monoclonal antibody (mAb) alone or in combination with sinomenine hydrochloride in vitro. Results suggested that anti-TfR mAb or sinomenine hydrochloride could induce apoptosis, inhibit proliferation, and affect the cell cycle. A synergistic effect was found in relation to tumor growth inhibition and the induction of apoptosis when anti-TfR mAb and sinomenine hydrochloride were used simultaneously. The expression of COX-2 and VEGF protein in HepG2 cells treated with anti-TfR mAb alone was increased in line with increasing dosage of the agent. In contrast, COX-2 expression was dramatically decreased in HepG2 cells treated with sinomenine hydrochloride alone. Furthermore, we demonstrated that the inhibitory effects of sinomenine hydrochloride and anti-TfR mAb administered in combination were more prominent than when the agents were administered singly. To sum up, these results showed that the combined use of sinomenine hydrochloride and anti-TfR mAb may exert synergistic inhibitory effects on human hepatoma HepG2 cells in a COX-2-dependent manner. This finding provides new insight into how tumor cells overcome the interference of iron intake to survive and forms the basis of a new therapeutic strategy involving the development of anti-TfR mAb combined with sinomenine hydrochloride for liver cancer.

Sinomenium acutum: a review of chemistry, pharmacology, pharmacokinetics, and clinical use

CONTEXT

Sinomenium acutum (Thumb.) Rehd. et Wils. (Menispermaceae, SA) has been used as a traditional Chinese medicine in the treatment of various diseases for hundreds of years; it possesses favorable effects against autoimmune diseases, especially rheumatoid arthritis (RA). A great number of investigations have been done on SA in the last decade, but they are usually scattered across various publications.

OBJECTIVE

The purpose of this article is to summarize and review the published scientific information about the chemical constituents, pharmacological effects, pharmacokinetics, and clinic applications of this plant since 2000.

RESULTS

The information for 89 cases included in this review was compiled. The SA contains alkaloids, sterols, phospholipids, and some other components. A great deal of pharmacological and clinic research has been done on sinomenine, a main compound from SA, which mainly focuses on the immune system, cardiovascular system, and nervous system.

CONCLUSION

Previous studies strongly support its potential as an effective adaptogenic herbal remedy. There is no doubt that SA is being widely used now and will have extraordinary potential for the future.

Sinomenine protects against ischaemic brain injury: involvement of co-inhibition of acid-sensing ion channel 1a and L-type calcium channels

BACKGROUND AND PURPOSE

Sinomenine (SN), a bioactive alkaloid, has been utilized clinically to treat rheumatoid arthritis in China. Our preliminary experiments indicated that it could protect PC12 cells from oxygen-glucose deprivation-reperfusion (OGD-R), we thus investigated the possible effects of SN on cerebral ischaemia and the related mechanism.

EXPERIMENTAL APPROACH

Middle cerebral artery occlusion in rats was used as an animal model of ischaemic stroke in vivo. The mechanisms of the effects of SN were investigated in vitro using whole-cell patch-clamp recording, calcium imaging in PC12 cells and rat cortical neurons subjected to OGD-R.

KEY RESULTS

Pretreatment with SN (10 and 30 mg·kg(-1) , i.p.) significantly decreased brain infarction and the overactivation of calcium-mediated events in rats subjected to 2 h ischaemia followed by 24 h reperfusion. Extracellular application of SN inhibited the currents mediated by acid-sensing ion channel 1a and L-type voltage-gated calcium channels, in the rat cultured neurons, in a concentration-dependent manner. These inhibitory effects contribute to the neuroprotection of SN against OGD-R and extracellular acidosis-induced cytotoxicity. More importantly, administration of SN (30 mg·kg(-1) , i.p.) at 1 and 2 h after cerebral ischaemia also decreased brain infarction and improved functional recovery.

CONCLUSION AND IMPLICATIONS

SN exerts potent protective effects against ischaemic brain injury when administered before ischaemia or even after the injury. The inhibitory effects of SN on acid-sensing ion channel 1a and L-type calcium channels are involved in this neuroprotection.

Two new morphinane alkaloids from Sinomenium acutum

Two new morphinane alkaloids, 1-hydroxy-10-oxo-sinomenine (1) and 4,5-epoxy-14-hydroxy sinomenine N-oxide (2), have been isolated from the stems of Sinomenium acutum. Their structures were established by various spectral analyses, especially 2D NMR experiments. The structure of 2 was confirmed by single crystal X-ray diffraction. The absolute configurations of 1 and 2 were deduced by comparison of CD spectra with the known alkaloid sinomenine (3). Compound 1 was tested for DPPH inhibition and gave IC(50) of 27.9 μM. Compound 2 was tested for neuroprotective effect and showed significant activity against β-amyloid(25-35)-induced oxidative injury (*P < 0.05) at 10 μM in PC-12 cells.