Quinolizidine alkaloids derivatives from Sophora alopecuroides Linn: Bioactivities, structure-activity relationships and preliminary molecular mechanisms

Design, synthesis and biological evaluation of aloperine derivatives as potential anticancer agents

Modifications at different positions on the aloperine molecule were performed to improve its anticancer activity and develop anticancer drugs. The in vitro anticancer activities of 44 synthesized compounds were evaluated. The effect of modification positions on anticancer activity was discussed and a structure-activity relationship analysis was established. A novel series of compounds with modifications at the N12 position showed much higher cytotoxicity than aloperine. Among them, compound 22 displayed promising in vitro anticancer activity against PC9 cells with a median inhibitory concentration (IC50) of 1.43 μM. The mechanism studies indicated that compound 22 induced cell apoptosis and cell cycle arrest in PC9 cells. These results demonstrate the potential of aloperine thiourea derivatives in anticancer activity.

Promising Role of Alkaloids in the Prevention and Treatment of Thyroid Cancer and Autoimmune Thyroid Disease: A Comprehensive Review of the Current Evidence

Thyroid cancer (TC) and thyroid autoimmune disorders (AITD) are among the most common diseases in the general population, with higher incidence in women. Chronic inflammation and autoimmunity play a pivotal role in carcinogenesis. Some studies, indeed, have pointed out the presence of AITD as a risk factor for TC, although this issue remains controversial. Prevention of autoimmune disease and cancer is the ultimate goal for clinicians and scientists, but it is not always feasible. Thus, new treatments, that overcome the current barriers to prevention and treatment of TC and AITD are needed. Alkaloids are secondary plant metabolites endowed with several biological activities including anticancer and immunomodulatory properties. In this perspective, alkaloids may represent a promising source of prophylactic and therapeutic agents for TC and AITD. This review encompasses the current published literature on alkaloids effects on TC and AITD, with a specific focus on the pathways involved in TC and AITD development and progression.

A review on the pharmacology, pharmacokinetics and toxicity of sophocarpine

Sophocarpine is a natural compound that belongs to the quinolizidine alkaloid family, and has a long history of use and widespread distribution in traditional Chinese herbal medicines such as Sophora alopecuroides L., Sophora flavescens Ait., and Sophora subprostrata. This article aims to summarize the pharmacology, pharmacokinetics, and toxicity of sophocarpine, evaluate its potential pharmacological effects in various diseases, and propose the necessity for further research and evaluation to promote its clinical application. A large number of studies have shown that it has anti-inflammatory, analgesic, antiviral, antiparasitic, anticancer, endocrine regulatory, and organ-protective effects as it modulates various signaling pathways, such as the NF-κB, MAPK, PI3K/AKT, and AMPK pathways. The distribution of sophocarpine in the body conforms to a two-compartment model, and sophocarpine can be detected in various tissues with a relatively short half-life. Although the pharmacological effects of sophocarpine have been confirmed, toxicity and safety assessments and reports on molecular mechanisms of its pharmacological actions have been limited. Given its significant pharmacological effects and potential clinical value, further research and evaluation are needed to promote the clinical application of sophocarpine.

Aloperine-Type Alkaloids with Antiviral and Antifungal Activities from the Seeds of Sophora alopecuroides L

As a continuous flow investigation of novel pesticides from natural quinolizidine alkaloids, the chemical compositions of the seeds of Sophora alopecuroides were thoroughly researched. Fifteen new aloperine-type alkaloids (1-15) as well as six known aloperine-type alkaloids (16-21) were obtained from the extract of S. alopecuroides. The structures of 1-21 were confirmed via HRESIMS, NMR, UV, IR, ECD calculations, and X-ray diffraction. The antiviral activities of 1-21 against tobacco mosaic virus (TMV) were detected following the improved method of half-leaf. Compared with ningnanmycin (protective: 69.7% and curative: 64.3%), 15 exhibited excellent protective (71.7%) and curative (64.6%) activities against TMV. Further biological studies illustrated that 15 significantly inhibited the transcription of the TMV-CP gene and increased the activities of polyphenol oxidase (PPO), peroxidase (POD), superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL). The antifungal activities of 1-21 against Phytophythora capsica, Botrytis cinerea, Alternaria alternata, and Gibberella zeae were screened according to a mycelial inhibition test. Compound 13 displayed excellent antifungal activity against B. cinerea (EC50: 7.38 μg/mL). Moreover, in vitro antifungal mechanism studies displayed that 13 causes accumulation of reactive oxygen species and finally leads to mycelia cell membrane damage and cell death in vitro.

Inhibitory effect of aloperine on transient outward potassium currents in rat cardiac myocytes

Objective

Aloperine (ALO) is an effective quinolizidine alkaloid. Previous research has demonstrated its antiarrhythmic effect by inhibiting voltage-gated sodium currents in rat ventricular myocytes. This study explored its effect on transient outward potassium currents (Ito) in rat atrial myocytes to identify potential targets in the context of ion channel currents.

Methods

The Ito characteristics in rat atrial myocytes were recorded using a whole-cell patch-clamp technique. Molecular docking was performed to validate ligand-protein binding interactions.

Results

ALO at concentrations of 3 and 10 μM significantly reduced Ito current densities. Gating kinetics analysis revealed ALO's ability to slow Ito activation, hasten inactivation, and prolong transition from inactive to resting state. Molecular docking revealed that ALO could stably bind to KCND2.

Conclusion

ALO may inhibit Ito by slowing the activation process, accelerating inactivation, and delaying the recovery time after inactivation, potentially preventing acetylcholine-induced AF.

Aloperine Alleviates Myocardial Injury Induced by Myocardial Ischemia and Reperfusion by Activating the ERK1/2/β-catenin Signaling Pathway

OBJECTIVE

Myocardial ischemia/reperfusion (I/R) injury can cause severe cardiac damage. Aloperine is a quinolizidine alkaloid found in the leaves and seeds of Sophora alopecuroides L. It has been recognized that aloperine has organ-protective properties; however, its role in cardioprotection is poorly characterized. This study aimed to evaluate the cardioprotective effects of aloperine against myocardial I/R injury in vivo.

METHODS

Adult male Sprague‒Dawley rats were randomly divided into sham-operated, control, and aloperine groups. All rats except for the sham-operated rats were subjected to 45 min of myocardial ischemia (by left anterior descending ligation) followed by 3 h of reperfusion. Aloperine (10 mg/kg) was given intravenously at the onset of reperfusion. The cardioprotective effects of aloperine were evaluated by determining infarct size, hemodynamics, histological changes, cardiac biomarkers, and cardiac apoptosis.

RESULTS

Aloperine limited infarct size; improved hemodynamics; attenuated myocardial I/R-induced histological deterioration; decreased serum LDH, CK-MB, and α-HBDH levels; and inhibited apoptosis after myocardial I/R injury. Moreover, aloperine stimulated the phosphorylation of ventricular ERK1/2, which is a major module of MAPK signaling pathways. Furthermore, aloperine increased the ventricular expression levels of β-catenin. Pharmacological inhibition of ERK1/2 diminished aloperine-induced cardioprotection and blocked ERK1/2/β-catenin signaling.

CONCLUSIONS

These data support the cardioprotective effect of aloperine against myocardial I/R injury, which is mediated, at least in part, by the ERK1/2/β-catenin signaling pathway.

Transcriptome-Based Identification of the SaR2R3-MYB Gene Family in Sophora alopecuroides and Function Analysis of SaR2R3-MYB15 in Salt Stress Tolerance

As one of the most prominent gene families, R2R3-MYB transcription factors significantly regulate biochemical and physiological processes under salt stress. However, in Sophora alopecuroides, a perennial herb known for its exceptional saline alkali resistance, the comprehensive identification and characterization of SaR2R3-MYB genes and their potential functions in response to salt stress have yet to be determined. We investigated the expression profiles and biological functions of SaR2R3-MYB transcription factors in response to salt stress, utilizing a transcriptome-wide mining method. Our analysis identified 28 SaR2R3-MYB transcription factors, all sharing a highly conserved R2R3 domain, which were further divided into 28 subgroups through phylogenetic analysis. Some SaR2R3-MYB transcription factors showed induction under salt stress, with SaR2R3-MYB15 emerging as a potential regulator based on analysis of the protein-protein interaction network. Validation revealed the transcriptional activity and nuclear localization of SaR2R3-MYB15. Remarkably, overexpression of SaR2R3-MYB15 in transgenic plants could increase the activity of antioxidant enzymes and the accumulation of proline but decrease the content of malondialdehyde (MDA), compared with wild-type plants. Moreover, several salt stress-related genes showed higher expression levels in transgenic plants, implying their potential to enhance salt tolerance. Our findings shed light on the role of SaR2R3-MYB genes in salt tolerance in S. alopecuroides.

Matrine and Oxymatrine: evaluating the gene mutation potential using in silico tools and the bacterial reverse mutation assay (Ames test)

The quinolizidine alkaloids matrine and its N-oxide oxymatrine occur in plants of the genus Sophora. Recently, matrine was sporadically detected in liquorice products. Morphological similarity of the liquorice plant Glycyrrhiza glabra with Sophora species and resulting confusion during harvesting may explain this contamination, but use of matrine as pesticide has also been reported. The detection of matrine in liquorice products raised concern as some studies suggested a genotoxic activity of matrine and oxymatrine. However, these studies are fraught with uncertainties, putting the reliability and robustness into question. Another issue was that Sophora root extracts were usually tested instead of pure matrine and oxymatrine. The aim of this work was therefore to determine whether matrine and oxymatrine have potential for causing gene mutations. In a first step and to support a weight-of-evidence analysis, in silico predictions were performed to improve the database using expert and statistical systems by VEGA, Leadscope (Instem®), and Nexus (Lhasa Limited). Unfortunately, the confidence levels of the predictions were insufficient to either identify or exclude a mutagenic potential. Thus, in order to obtain reliable results, the bacterial reverse mutation assay (Ames test) was carried out in accordance with OECD Test Guideline 471. The test set included the plate incorporation and the preincubation assay. It was performed with five different bacterial strains in the presence or absence of metabolic activation. Neither matrine nor oxymatrine induced a significant increase in the number of revertants under any of the selected experimental conditions. Overall, it can be concluded that matrine and oxymatrine are unlikely to have a gene mutation potential. Any positive findings with Sophora extracts in the Ames test may be related to other components. Notably, the results also indicated a need to extend the application domain of respective (Q)SAR tools to secondary plant metabolites.

Community ecological succession of endophytic fungi associates with medicinal compound accumulation in Sophora alopecuroides

Endophytic fungi of medicinal plants are symbiotic with the host and play an important role in determining metabolites. To understand the relationship between the accumulation of Sophora alopecuroides' medicinal bioactive compounds and the ecological succession of endophytic fungi, here we collected samples from S. alopecuroides at four developmental stages (adult, flowering, podding, and mature) and different organs (roots, stems, leaves, and seeds) at the mature stage. We then used high-performance liquid chromatography-mass spectrometry and high-throughput sequencing on the internal transcribed spacer region to identify the medicinal compounds and endophytic fungal communities in each sample. The endophytic fungal community characteristics and accumulation of medicinally bioactive compounds of S. alopecuroides varied with the host's developmental stages and organs, with the highest total alkaloids content of 111.9 mg/g at the mature stage. Membership analysis and network connection analysis showed a total of 15 core endophytic fungi in different developmental stages and 16 core endophytic fungi in different organs at the mature stage. The unclassified Ascomycota, Aspergillus, and Alternaria were significantly and positively correlated with the medicinal compounds of S. alopecuroides at the mature stage (r > 0.6 or r < -0.6; P < 0.05). In this study, we identified key endophytic fungal resources that affect the content of medicinally bioactive compounds in S. alopecuroides. This discovery could lay the foundation for enhancing the yield of medicinally bioactive compounds in S. alopecuroides and the development and application of functional endophytic fungi.IMPORTANCESophora alopecuroides is a traditional Chinese herbal medicine. The major medicinal chemicals are considered to be quinolizidine alkaloids. Quinolizidine alkaloids have been widely used for the treatment of tumors, dysentery, and enteritis. Previous studies have found that endophytic fungi in S. alopecuroides can promote the accumulation of host quinolizidine alkaloids. However, the relationship between the accumulation of S. alopecuroides' medicinal bioactive compounds and the ecological succession of endophytic fungi remains unclear. In this study, we screened the key endophytic fungal resources affecting the content of medicinally bioactive compounds and laid the foundation for subsequent research on the mechanism by which endophytic fungi promote the accumulation of medicinally bioactive compounds in S. alopecuroides.

Sophoridine Counteracts Obesity via Src-Mediated Inhibition of VEGFR Expression and PI3K/AKT Phosphorylation

Sophoridine (SRP) is a natural quinolizidine alkaloid found in many traditional Chinese herbs, though its effect on adipose tissue is unclear. We improved serum lipid levels by administering SRP by gavage in high-fat diet (HFD)-fed C57BL/6 mice. After 11 weeks, SRP supplementation significantly reduced body weight gain and improved glucose homeostasis, while reducing subcutaneous fat and liver weight. SRP also inhibited cell proliferation and differentiation of 3T3-L1 cells. Proteomics analysis revealed that SRP inhibits adipocyte differentiation by interacting with Src, thereby suppressing vascular endothelial growth factor receptor 2 (VEGFR2) expression and PI3K/AKT phosphorylation. This study provides an empirical basis for the treatment of obesity with small molecules.

Exploring Derivatives of Quinolizidine Alkaloid Sophoridine in the Design and Biological Mechanistic Evaluation of Histone Deacetylase Inhibitors against Triple-Negative Breast Cancer

As a critical epigenetic modulator of gene expression, histone deacetylases (HDACs) have been involved in the pathogenesis and therapeutic investigation of cancer. Quinolizidine alkaloid sophoridine is known to have anticancer efficacy but with limited indication. By incorporating the pharmacophore of the HDAC inhibitor into the ring-opened sophoridine core, a new series of sophoridine hydroxamic acid derivatives were synthesized. After structure-activity studies, a selected compound was found to exert significant cytotoxicity in triple-negative breast cancer CAL-51 cells (IC50 1.17 μM), and demonstrated low nanomolar inhibitory potency toward HDAC1/3/6. Cellular functional assays indicated that this compound was able to induce apoptosis and cause accumulation of cells in the S phase of the cell cycle. Western blot analysis revealed it to decrease the expression of DNMT1, DNMT3a and DNMT3b by down-regulating phosphor-ERK1/2. Furthermore, treatment with this compound proved to block the PI3K/AKT/mTOR signaling in the PI3KCA and PTEN-mutant CAL-51 cells. Collectively, this work provides a novel lead compound for the development of potential therapeutics against triple-negative breast cancers, possibly mesenchymal-like subtype.

Biochar and organic fertilizer drive the bacterial community to improve the productivity and quality of Sophora tonkinensis in cadmium-contaminated soil

Excessive Cd accumulation in soil reduces the production of numerous plants, such as Sophora tonkinensis Gagnep., which is an important and widely cultivated medicinal plant whose roots and rhizomes are used in traditional Chinese medicine. Applying a mixture of biochar and organic fertilizers improved the overall health of the Cd-contaminated soil and increased the yield and quality of Sophora. However, the underlying mechanism between this mixed fertilization and the improvement of the yield and quality of Sophora remains uncovered. This study investigated the effect of biochar and organic fertilizer application (BO, biochar to organic fertilizer ratio of 1:2) on the growth of Sophora cultivated in Cd-contaminated soil. BO significantly reduced the total Cd content (TCd) in the Sophora rhizosphere soil and increased the soil water content, overall soil nutrient levels, and enzyme activities in the soil. Additionally, the α diversity of the soil bacterial community had been significantly improved after BO treatment. Soil pH, total Cd content, total carbon content, and dissolved organic carbon were the main reasons for the fluctuation of the bacterial dominant species. Further investigation demonstrated that the abundance of variable microorganisms, including Acidobacteria, Proteobacteria, Bacteroidetes, Firmicutes, Chloroflexi, Gemmatimonadetes, Patescibacteria, Armatimonadetes, Subgroups_ 6, Bacillus and Bacillus_ Acidiceler, was also significantly changed in Cd-contaminated soil. All these alterations could contribute to the reduction of the Cd content and, thus, the increase of the biomass and the content of the main secondary metabolites (matrine and oxymatrine) in Sophora. Our research demonstrated that the co-application of biochar and organic fertilizer has the potential to enhance soil health and increase the productivity and quality of plants by regulating the microorganisms in Cd-contaminated soil.

Sophocarpine alleviates doxorubicin-induced heart injury by suppressing oxidative stress and apoptosis

Doxorubicin (DOX) is an effective anti-tumor drug accompanied with many side effects, especially heart injury. To explore what effects of sophocarpine (SOP) on DOX-induced heart injury, this study conducted in vivo experiment and in vitro experiment, and the C57BL/6J mice and the H9C2 cells were used. The experimental methods used included echocardiography, enzyme-linked immunosorbent assay (ELISA), dihydroethidium (DHE) staining, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, western blotting and so on. Echocardiography showed that SOP alleviated DOX-induced cardiac dysfunction, as evidenced by the improvements of left ventricle ejection fraction and left ventricle fractional shortening. DOX caused upregulations of creatine kinase (CK), creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH), while SOP reduced these indices. The relevant stainings showed that SOP reversed the increases of total superoxide level induced by DOX. DOX also contribute to a higher level of MDA and lower levels of SOD and GSH, but these changes were suppressed by SOP. DOX increased the pro-oxidative protein level of NOX-4 while decreased the anti-oxidative protein level of SOD-2, but SOP reversed these effects. In addition, this study further discovered that SOP inhibited the decreases of Nrf2 and HO-1 levels induced by DOX. The TUNEL staining revealed that SOP reduced the high degree of apoptosis induced by DOX. Besides, pro-apoptosis proteins like Bax, cleaved-caspase-3 and cytochrome-c upregulated while anti-apoptosis protein like Bcl-2 downregulated when challenged by DOX, but them were suppressed by SOP. These findings suggested that SOP could alleviate DOX-induced heart injury by suppressing oxidative stress and apoptosis, with molecular mechanism activating of the Nrf2/HO-1 signaling pathway.

Design, synthesis and triglyceride-lowering activity of tricyclic matrine derivatives for the intervention of non-alcoholic fatty liver disease

Thirty new tricyclicmatrinic derivatives were successively synthesized and evaluated for their inhibitory activity on the accumulation of triglycerides (TG) in AML12 cells, using 12 N-m-trifluoromethylbenzenesulfonyl matrine (1) as the hit compound. Among the analogues, compound 7n possessing 11-trimethylbutylamine quaternary exerted the highest in vitro TG-lowering potency, as well as a good safety profile. 7n significantly attenuated the hepatic injury and steatosis, and ameliorated dyslipidemia and dysglycemia in the mice with non-alcoholic fatty liver disease (NAFLD) induced by a high-fat diet. Primary mechanism study revealed that upregulation of peroxisome proliferator-activated receptors α (PPARα)-carnitine palmitoyltransferase 1A (CPT1A) pathway mediated the efficacy of 7n. Our study provides powerful information for developing this kind of compound into a new class of anti-NAFLD candidates, and compound 7n is worthy of further investigation as an ideal lead compound.

Alkaloids from the roots of Sophora flavescens and their anti-tumor activity

Sophora flavescens belongs to Sophora genus of Leguminosae. Its roots are used as a traditional Chinese medicine. In our study on Sophora flavescens roots, 3 new and 19 known alkaloids have been found, including 8 aloperine-type and 14 matrine-type alkaloids. The planar configurations of these compounds were determined by the spectral data, and the absolute configurations of new compounds 1, 2 and 4 were determined by pyridine solvent effect, ECD and snatzke methods, respectively. All compounds were tested for their inhibitory activity on MCF-7 cell growth, and compound 12 exhibited certain inhibitory effects on the growth of MCF-7 cells after 24 h of treatment at a concentration of 20 μM, with inhibition rates of 31.28%. Through target screening and molecular docking, human Rho GTPase activating protein 5 variant and human arachidonate 12-lipoxygenase (12S-type) might be important targets for compound 12 to exert anti-tumor activity.

The characteristics and molecular targets of antiarrhythmic natural products

Arrhythmia is one of the most common cardiovascular diseases. The search for new drugs to suppress various types of cardiac arrhythmias has always been the focus of attention. In the past decade, the screening of antiarrhythmic active substances from plants has received extensive attention. These natural compounds have obvious antiarrhythmic effects, and chemical modifications based on natural compounds have greatly increased their pharmacological properties. The chemical modification of botanical antiarrhythmic drugs is closely related to the development of new and promising drugs. Therefore, the structural characteristics and action targets of natural compounds with antiarrhythmic effects are reviewed in this paper, so that pharmacologists can select antiarrhythmic lead compounds from natural compounds based on the disease target - chemical structural characteristics.

Aloperine targets lysosomes to inhibit late autophagy and induces cell death through apoptosis and paraptosis in glioblastoma

Glioblastoma (GBM) is an aggressive intracranial tumour, and current chemotherapy regimens have limited efficacy. Aloperine (ALO), a natural alkaline compound, has shown potential as an antitumor agent. However, the effect of ALO against GBM remains unclear. This study aimed to investigate the function of ALO in treating GBM. U87, A172, and GL261 cell lines were used for in vitro experiments, and GL261 was also used to establish in vivo models. The results showed that ALO inhibited the proliferation of GBM cells by cell cycle arrest and apoptosis. Furthermore, autophagy was found to play a critical role, suggested by observation of autophagosomes under the transmission electron microscopy. It was discovered for the first time that ALO targeted lysosomes directly in glioma cells, tested by fluo-rescence-labelled ALO and organelle-localizing probes. In addition, ALO inhibited late autophagy and induced paraptosis in GBM, verified by classical gene expression changes in qPCR and western blotting. Also, ALO inhibited tumour growth and acted synergistically with temozolomide in intracranial glioma mice models in vivo. Our findings suggest that ALO targets lysosomes to inhibit late autophagy in GBM, inducing cell cycle arrest, paraptosis, and apoptosis. ALO may therefore be a promising therapeutic agent for the treatment of GBM.

Further Quinolizidine Derivatives as Antiarrhythmic Agents- 3

Fourteen quinolizidine derivatives, structurally related to the alkaloids lupinine and cytisine and previously studied for other pharmacological purposes, were presently tested for antiarrhythmic, and other cardiovascular effects on isolated guinea pig heart tissues in comparison to well-established reference drugs. According to their structures, the tested compounds are assembled into three subsets: (a) N-(quinolizidinyl-alkyl)-benzamides; (b) 2-(benzotriazol-2-yl)methyl-1-(quinolizidinyl)alkyl-benzimidazoles; (c) N-substituted cytisines. All compounds but two displayed antiarrhythmic activity that was potent for compounds 4, 1, 6, and 5 (in ascending order). The last compound (N-(3,4,5-trimethoxybenzoyl)aminohomolupinane) was outstanding, exhibiting a nanomolar potency (EC50 = 0.017 µM) for the increase in the threshold of ac-arrhythmia. The tested compounds shared strong negative inotropic activity; however, this does not compromise the value of their antiarrhythmic action. On the other hand, only moderate or modest negative chronotropic and vasorelaxant activities were commonly observed. Compound 5, which has high antiarrhythmic potency, a favorable cardiovascular profile, and is devoid of antihypertensive activity in spontaneously hypertensive rats, represents a lead worthy of further investigation.

Natural products as the calcium channel blockers for the treatment of arrhythmia: Advance and prospect

Arrhythmia is one of the commonly heart diseases with observed abnormal heart-beat rhythm that caused by the obstacles of cardiac activity and conduction. The arrhythmic pathogenesis is complex and capricious and related with other cardiovascular diseases that may lead to heart failure and sudden death. In particular, calcium overload is recognized as the main reason causing arrhythmia through inducing apoptosis in cardiomyocytes. Moreover, calcium channel blockers have been widely used as the routine drugs for the treatment of arrhythmia, but the different arrhythmic complications and adverse effects limit their further applications and demand new drug discovery. Natural products have always been the rich minerals for the development of new drugs that could be employed as the versatile player for the discovery of safe and effective anti-arrhythmia drugs with new mechanisms. In this review, we summarized natural products with the activity against calcium signaling and the relevant mechanism of actions. We are expected to provide an inspiration for the pharmaceutical chemists to develop more potent calcium channel blockers for the treatment of arrhythmia.

Quinolizidine-Type Alkaloids: Chemodiversity, Occurrence, and Bioactivity

Quinolizidine alkaloids (QAs) are nitrogen-containing compounds produced naturally as specialized metabolites distributed in plants and animals (e.g., frogs, sponges). The present review compiles the available information on the chemical diversity and biological activity of QAs reported during the last three decades. So far, 397 QAs have been isolated, gathering 20 different representative classes, including the most common such as matrine (13.6%), lupanine (9.8%), anagyrine (4.0%), sparteine (5.3%), cytisine (6.5%), tetrahydrocytisine (4.3%), lupinine (12.1%), macrocyclic bisquinolizidine (9.3%), biphenylquinolizidine lactone (7.1%), dimeric (7.1%), and other less known QAs (20.9%), which include several structural patterns of QAs. A detailed survey of the reported information about the bioactivities of these compounds indicated their potential as cytotoxic, antiviral, antimicrobial, insecticidal, anti-inflammatory, antimalarial, and antiacetylcholinesterase compounds, involving favorable putative drug-likeness scores. In this regard, research progress on the structural and biological/pharmacological diversity of QAs requires further studies oriented on expanding the chemical space to find bioactive scaffolds based on QAs for pharmacological and agrochemical applications.

Induced neural stem cells suppressed neuroinflammation by inhibiting the microglial pyroptotic pathway in intracerebral hemorrhage rats

Intracerebral hemorrhage usually manifests as strong neuroinflammation and neurological deficits. There is an urgent need to explore effective methods for the treatment of intracerebral hemorrhage. The therapeutic effect and the possible mechanism of induced neural stem cell transplantation in an intracerebral hemorrhage rat model are still unclear. Our results showed that transplantation of induced neural stem cells could improve neurological deficits by inhibiting inflammation in an intracerebral hemorrhage rat model. Additionally, induced neural stem cell treatment could effectively suppress microglial pyroptosis, which might occur through inhibiting the NF-κB signaling pathway. Induced neural stem cells could also regulate the polarization of microglia and promote the transition of microglia from pro-inflammatory phenotypes to anti-inflammatory phenotypes to exert their anti-inflammatory effects. Overall, induced neural stem cells may be a promising tool for the treatment of intracerebral hemorrhage and other neuroinflammatory diseases.

Therapeutic action of Kushen recipe extractive and its inhibitory effect on eotaxin in mouse models with contact dermatitis

BACKGROUND

Treatment of skin allergic diseases remains a challenging research topic.

OBJECTIVE

To investigate the effect of Kushen recipe extractive (KS) gel on contact dermatitis (CD) of mouse.

METHODS

Allergic contact dermatitis (ACD) model of mouse was established. Immunohistochemical method (ICH) and flow cytometry method (FCM) were used to detect CD4⁺ and CD8⁺ T lymphocytes and explore the regulation effect of KS on the immune status of the organism. The expression status of eotaxin tissue was evaluated by real-time polymerase chain reaction (RT-PCR), ICH, and western blotting method. The survival rates of HaCaT cell and Fibroblasts affected by KS were detected by methyl thiazolyl tetrazolium (MTT) method. The inhibitory effect of KS on eotaxin produced by HaCaT cell and FBs induced by TNF-α and interleukin (IL)-4 were evaluated using RT-PCR and enzyme-linked immunosorbent assay methods. The inhibitory effect of KS on nuclear factor-κB (NF-κB) and Signal transducers and activators of transcription 6 (STAT6) activation induced by TNF-α and IL-4 was detected by electrophoretic mobility shift assay and western blotting methods.

RESULTS

We confirmed that KS shows favorable therapeutic effect on CD, which can obviously inhibit eotaxin expression and Eosinophils recruitment in allergic skin of mouse, as well as regulate the immune status of the organism. Furthermore, KS and its main effective components can inhibit TNF-α and IL-4 induced upregulation of eotaxin via the two signal transduction pathways, NF-κB and STAT6.

CONCLUSIONS

The great importance of traditional Chinese recipe KS is evidenced by its therapeutic effect and mechanism in ACD of mouse.

Evolution and Discovery of Matrine Derivatives as a New Class of Anti-Hepatic Fibrosis Agents Targeting Ewing Sarcoma Breakpoint Region 1 (EWSR1)

A series of new tricyclic matrinane derivatives were continuously synthesized and evaluated for their inhibitory effects on genes and proteins related to hepatic fibrosis at the cellular level, including collagen type I α1 chain (COL1A1), α smooth muscle actin (α-SMA), connective tissue growth factor (CTGF), and matrix metalloprotein 2 (MMP-2). Among them, compound 6k exerted an appealing potency and significantly reduced liver injury and fibrosis in both bile duct ligation (BDL) rats and Mdr2 knockout mice. An activity-based protein profiling (ABPP) assay indicated that 6k might directly bind to Ewing sarcoma breakpoint region 1 (EWSR1) to inhibit its function and affect the expression of downstream liver fibrosis-related genes and thus regulate liver fibrosis. These results provided a potential novel target for the treatment of liver fibrosis and powerful information for the development of tricyclic matrinanes into promising anti-hepatic fibrosis agents.

The protective effects of sophocarpine on sepsis-induced cardiomyopathy

This investigation elucidates the impact of sophocarpine treatment on lipopolysaccharide (LPS) stimulated sepsis-induced cardiomyopathy (SIC) via in vivo and in vitro experiments. Echocardiography, ELISA, TUNEL, Western blotting experiments, and Hematoxylin/Eosin, Dihydroethidium, and Immunohistochemistry staining assays, were carried out to identify associated indicators. The echocardiography revealed that sophocarpine treatment alleviated LPS-induced cardiac dysfunction as indicated by fractional shortening shortened and improved ejection fraction. Heart injury biomarkers, such as creatine kinase, lactate dehydrogenase, and creatine kinase-MB, were assessed, and indicated that sophocarpine treatment could alleviate LPS-induced upregulation of these indices. Furthermore, different experimental protocols revealed that sophocarpine treatment inhibits LPS-induced pathological alterations and decreases LPS-stimulated inflammatory cytokines, IL-1β, monocyte chemoattractant protein-1, IL-6, NOD-like receptor protein-3, and TNF-α, increase. Apoptotic proteins such as cytochrome-c, Bax, and cleaved-caspase-3 were increased, and Bcl-2 was alleviated after LPS stimulation; however, these effects were inhibited by sophocarpine treatment. Decreased antioxidant proteins [superoxide dismutase-1 (SOD-1) and SOD-2] induced by LPS stimulation were upregulated by sophocarpine treatment. LPS upregulated autophagic proteins such as Beclin-1 and the ratio of microtubule-associated protein 1A/1B-light chain 3 (LC3)-II/LC3-I and downregulated sequestosome 1 (SQSTM1, or P62), sophocarpine therapy reversed these effects. Moreover, it was indicated that sophocarpine treatment inhibited the Toll-like receptor-4 (TLR-4)/nuclear transcription factor-kappa B (NF-κB) signaling pathway and activated nuclear factor erythroid 2-related factor-2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway. In conclusion, sophocarpine treatment could alleviate LPS-trigger SIC by repressing oxidative stress, autophagy, inflammation, and apoptosis via TLR-4/NF-κB inhibition and Nrf2/HO-1 signaling pathway activation, implicating the potential of sophocarpine as a new therapeutic approach against SIC.

Pharmacological mechanism of natural drugs and their active ingredients in the treatment of arrhythmia via calcium channel regulation

Arrhythmia is characterized by abnormal heartbeat rhythms and frequencies caused by heart pacing and conduction dysfunction. Arrhythmia is the leading cause of death in patients with cardiovascular disease, with high morbidity and mortality rates, posing a serious risk to human health. Natural drugs and their active ingredients, such as matrine(MAT), tetrandrine(TET), dehydroevodiamine, tanshinone IIA, and ginsenosides, have been widely used for the treatment of atrial fibrillation, ventricular ectopic beats, sick sinus syndrome, and other arrhythmia-like diseases owing to their unique advantages. This review summarizes the mechanism of action of natural drugs and their active ingredients in the treatment of arrhythmia via the regulation of Ca²⁺, such as alkaloids, quinones, saponins, terpenoids, flavonoids, polyphenols, and lignan compounds, to provide ideas for the innovative development of natural drugs with potential antiarrhythmic efficacy.

Novel Matrine Derivatives as Potential Larvicidal Agents against Aedes albopictus: Synthesis, Biological Evaluation, and Mechanistic Analysis

A large number of studies have shown that matrine (MA) possesses various pharmacological activities and is one of the few natural, plant-derived pesticides with the highest prospects for promotion and application. Fifty-eight MA derivatives were prepared, including 10 intermediates and 48 target compounds in 3 series, to develop novel mosquitocidal agents. Compounds 4b, 4e, 4f, 4m, 4n, 6e, 6k, 6m, and 6o showed good larvicidal activity against Aedes albopictus, which is both a highly aggressive mosquito and an important viral vector that can transmit a wide range of pathogens. Dipping methods and a bottle bioassay were used for insecticidal activity evaluation. The LC50 values of 4e, 4m, and 6m reached 147.65, 140.08, and 205.79 μg/mL, respectively, whereas the LC50 value of MA was 659.34 μg/mL. Structure–activity relationship analysis demonstrated that larvicidal activity could be improved by the unsaturated heterocyclic groups introduced into the carboxyl group after opening the D ring. The MA derivatives with oxidized N-1 lost their mosquitocidal activities, indicating that the bareness of N-1 is crucial to maintain their anti-mosquito activity. However, the activity was not greatly influenced by introducing a cyan group at C-6 or a benzene sulfonyl group at N-16. Additionally, compounds 4e and 4m exhibited good inhibitory activities against acetylcholinesterase with inhibitory rates of 59.12% and 54.30%, respectively, at a concentration of 250 μg/mL, whereas the inhibitory rate of MA was 9.88%. Therefore, the structural modification and mosquitocidal activity of MA and its derivatives obtained here pave the way for those seeking strong mosquitocidal agents of plant origin.

Lewis Acid-Catalyzed Formal (4+2)-Cycloaddition between Cross-Conjugated Azatrienes and Styrylmalonates: The Way to Functionalized Quinolizidine Precursors

Quinolizidine and azaphenalene alkaloids are common in nature and exhibit a pharmaceutical activity, which stirs up increased interest in expanding the range of methods for the synthesis of the corresponding derivatives. In this work, we attempted to adapt our previously presented method for the synthesis of tetrahydropyridines to the preparation of potential precursors for these heterocycles as a separate development of a necessary intermediate stage. To this end, we studied the reactions of β-styrylmalonates with N-protected cross-conjugated azatrienes in the presence of Sn(OTf)₂. Moreover, the regioselectivity of the process involving unsymmetrically substituted azatrienes was estimated. The diene character of vinyltetrahydropyridines was studied in detail with the participation of PTAD. Finally, for the Ts-protected highly functionalized vinyltetrahydropyridines synthesized, a detosylation method to give new desired azadiene structures as precursors of the quinolizidine core was suggested.

Sophocarpine Alleviates Isoproterenol-Induced Kidney Injury by Suppressing Inflammation, Apoptosis, Oxidative Stress and Fibrosis

One of the most common diseases affecting people and leading to high morbidity is kidney injury. The alleviation of inflammation and apoptosis is considered a potential therapeutic approach for kidney injury. Sophocarpine (SOP), a tetracyclic quinolizidine alkaloid, exhibits various beneficial biological properties. To investigate the effects of SOP on isoproterenol (ISO)-induced kidney injury, we randomly divided mice into four groups: Control, ISO, ISO+SOP (20 mg/kg) and ISO+SOP (40 mg/kg). SOP was administered intraperitoneally to the mice over two weeks, accompanied by intraperitoneal stimulation of ISO (10 mg/kg) for another four weeks. After the mice were sacrificed, several methods such as ELISA, staining (H&E, TUNEL, DHE and Masson) and Western blotting were applied to detect the corresponding indicators. The kidney injury serum biomarkers SCr and BUN increased after the ISO challenge, while this effect was reversed by treatment with SOP. Pathological changes induced by ISO were also reversed by treatment with SOP in the staining. The inflammatory cytokines IL-β, IL-6, TNF-α, MCP-1 and NLRP3 increased after the challenge with ISO, while they were decreased by treatment with SOP. The apoptotic proteins cleaved-caspase-3 and Bax increased, while Bcl-2 decreased, after the challenge with ISO, and these effects were reversed by treatment with SOP. The antioxidant proteins SOD-1 and SOD-2 decreased after being stimulated by ISO, while they increased after the treatment with SOP. The fibrotic proteins collagen I, collagen III, α-SMA, fibronectin, MMP-2 and MMP-9 increased after the challenge with ISO, while they decreased after the treatment with SOP. We further discovered that the TLR-4/NF-κB and TGF-β1/Smad3 signaling pathways were suppressed, while the Nrf2/HO-1 signaling pathway was activated. In summary, SOP could alleviate ISO-induced kidney injury by inhibiting inflammation, apoptosis, oxidative stress and fibrosis. The molecular mechanisms were suppression of the TLR-4/NF-κB and TGF-β1/Smad3 signaling pathways and activation of the Nrf2/HO-1 signaling pathway, indicating that SOP might serve as a novel therapeutic strategy for kidney injury.

Synthesis and Evaluation of 11-Butyl Matrine Derivatives as Potential Anti-Virus Agents

Matrine derivatives were reported to have various biological activities, especially the ester, amide or sulfonamide derivatives of matrine deriving from the hydroxyl or carboxyl group at the end of the branch chain after the D ring of matrine is opened. In this work, to investigate whether moving away all functional groups from the C-11 branch chain could have an impact on the bioactivities, such as anti-tobacco mosaic virus (TMV), insecticidal and fungicidal activities, a variety of N-substituted-11-butyl matrine derivatives were synthesized. The obtained bioassay result showed that most N-substituted-11-butyl matrine derivatives had obviously enhanced anti-TMV activity compared with matrine, especially many compounds had good inhibitory activity close to that of commercialized virucide Ningnanmycin (inhibition rate 55.4, 57.8 ± 1.4, 55.3 ± 0.5 and 60.3 ± 1.2% at 500 μg/mL; 26.1, 29.7 ± 0.2, 24.2 ± 1.0 and 27.0 ± 0.3% at 100 μg/mL, for the in vitro activity, in vivo inactivation, curative and protection activities, respectively). Notably, N-benzoyl (7), N-benzyl (16), and N-cyclohexylmethyl-11-butyl (19) matrine derivatives had higher anti-TMV activity than Ningnanmycin at both 500 and 100 μg/mL for the four test modes, showing high potential as anti-TMV agent. Furthermore, some compounds also showed good fungicidal activity or insecticidal activity.

Effects and mechanisms of natural alkaloids for prevention and treatment of osteoporosis

Natural alkaloids are polycyclic, nitrogen-containing, and basic compounds obtained from plants. In this review, the advances in bioactive alkaloids with respect to their chemical structures, herbal sources, and effects for the prevention and treatment of osteoporosis are discussed. Anti-osteoporosis alkaloids are classified into six categories based on the chemical structure, namely, isoquinoline alkaloids, quinolizidine alkaloids, piperidine alkaloids, indole alkaloids, pyrrolizidine alkaloids and steroidal alkaloids. They promote mesenchymal stem cells differentiation, improve osteoblast proliferation, stimulate osteoblast autophagy and suppress osteoclast formation. These natural alkaloids can regulate multiple signaling pathways, including interrupting the tumor necrosis factor receptor associated factor 6- receptor activator of nuclear factor kappa B interaction, inhibiting the nuclear factor kappa B pathway in osteoclasts, activating the p38 mitogen-activated protein kinases pathway in osteoblasts, and triggering the wingless and int-1 pathway in mesenchymal stem cells. This review provides evidence and support for novel drug and clinical treatment of osteoporosis using natural alkaloids.

Sophocarpine inhibits tumor progression by antagonizing the PI3K/AKT/mTOR signaling pathway in castration-resistant prostate cancer

Objective

The objective of this study was to investigate the inhibitory effect of sophocarpine on the progression of castration-resistant prostate cancer (CRPC) and the underlying molecular mechanism.

Methods

DU145 and PC3 cells (two CRPC cell lines), incubated with different concentrations of sophocarpine, were used. Cell Counting Kit-8 assay, real-time cellular analysis, and colony formation assay were conducted to evaluate the proliferation of CRPC cells. Cytometry flow analysis was performed to evaluate the apoptosis rate of CRPC cells. Wound healing and Transwell invasion assays were performed and the levels of the epithelial-mesenchymal transition (EMT)-related proteins were determined to analyze cell migration and invasion abilities. A xenografted tumor model of nude mice was used to examine the anti-cancer effect of sophocarpine on CRPC. Western blotting was performed to evaluate the activities of the PI3K/AKT/mTOR signaling pathway both in cells and tumor tissues.

Results

In vitro tests showed that sophocarpine suppressed the proliferation of CRPC cells, reduced the migration and invasion abilities, and increased the apoptosis rate. In vivo, sophocarpine decreased the weight and volume of tumor tissues. Mechanically, sophocarpine exerted its anti-cancer effects by inactivating PI3K/AKT/mTOR signaling.

Conclusion

Sophocarpine inhibited the progression of CRPC by downregulating the PI3K/AKT/mTOR signaling pathway and showed a potential to be an anti-cancer agent against CRPC.

Correlation in endophytic fungi community diversity and bioactive compounds of Sophora alopecuroides

Sophora alopecuroides L. is a traditional Chinese medicine used for the treatment of several different disease states including bacillary dysentery and enteritis. But importantly, it also plays a role as an anti-tumor agent. That said, little is known about the role endophytes play regarding the clinically bioactive metabolites in S. alopecuroides. In order to explore the effects of endophytic fungi on the accumulation, quality, and correlation in the content of the medicinal compounds, the structural diversity of endophytic fungi in S. alopecuroides was analyzed. The relationship between endophytes and quinolizidine alkaloids (QAs), housed within the seeds of S. alopecuroides, which were interpreted based on established methods of high-throughput sequencing and high-performance liquid chromatography. A total of 1,034,418 effective sequence reads and 257 operational taxonomic units (OTUs) were obtained from 33 samples which were sourced from 11 different sampling sites and further classified into 9 phyla, 20 classes, 45 orders, 85 families, and 118 genera. Ascomycota was found to be the dominant phylum of endophytic fungi in S. alopecuroides, with a relative abundance ranging from 60.85 to 98.30%. Alternaria, Cladosporium, Filobasidium, and an unidentified Ascomycota were the core-shared endophytes, accounting for 49.96, 27.12, 14.83, and 7.88%, respectively. Correlation analysis showed that the Simpson's diversity index of endophytic fungal community in S. alopecuroides was significantly positively correlated with the Oxymatrine (OMA) content in different areas, while the Chao and Shannoneven indexes were significantly negatively correlated with OMA. The endophytic fungi of Alternaria were positively correlated with the content of OMA, Oxysophocarpine (OSC), and total QAs. This study has mastered the endophytic fungi resources of S. alopecuroides, explored potential functional endophytic fungi, and provided a scientific basis for using biological fertilization strategies to improve the quality of S. alopecuroides.

Matrine@chitosan-D-proline nanocapsules as antifouling agents with antibacterial properties and biofilm dispersibility in the marine environment

Antifoulants are the most vital substances in antifouling coatings to prevent marine organisms from colonizing the undersea substrate surfaces. In addition to antibacterial performance, inhibition of biofilm formation is an important criterion for antifouling coatings. In this study, we synthesized pH-responsive matrine@chitosan-D-proline (Mat@CS-Pro) nanocapsules of about 280 nm with antibacterial properties and biofilm dispersibility. The prepared Mat@CS-Pro nanocapsules exhibited high-level antibacterial properties, reaching about 93, 88, and 96% for E. coli, S. aureus, and P. aeruginosa, respectively. Such nanocapsules can cause irreversible damage to bacteria and cause them to lose their intact cell structures. Moreover, Mat@CS-Pro nanocapsules also possessed outstanding dispersal biofilm performances, in which the biofilm thickness of E. coli, S. aureus, and P. aeruginosa was decreased by 33, 74, and 42%, respectively, after 3 days of incubation. Besides, the Mat@CS-Pro nanocapsules had remarkable pH-responsive properties. As the environmental pH became acidic, the nanocapsules swelled to about 475 nm and the released concentration could reach 28.5 ppm after immersion for 10 h but maintained a low releasing rate in pH 8 conditions.

Recent progress on vascular endothelial growth factor receptor inhibitors with dual targeting capabilities for tumor therapy

Vascular endothelial growth factor receptors (VEGFRs) are a family of receptor protein tyrosine kinases that play an important role in the regulation of tumor-induced angiogenesis. Currently, VEGFR inhibitors have been widely used in the treatment of various tumors. However, current VEGFR inhibitors are limited to a certain extent due to limited clinical efficacy and potential toxicity, which hinder their clinical application. Thus, the development of new strategies to improve the clinical outcomes and minimize the toxic effects of VEGFR inhibitors is required. Given the synergistic effect of VEGFR and other therapies in tumor development and progression, VEGFR dual-target inhibitors are becoming an attractive approach due to their favorable pharmacodynamics, low toxicity, and anti-resistant effects. This perspective provides an overview of the development of VEGFR dual-target inhibitors from multiple aspects, including rational target combinations, drug discovery strategies, structure–activity relationships and future directions.

Discovery, Topo I inhibitory activity and mechanism evaluation of two novel cytisine-type alkaloid dimers from the seeds of Sophora alopecuroides L

Alopecurosines A and B (CMs 1 and 2, respectively) are two novel cytisine-type alkaloid dimers first isolated from the aerial parts of Sophora alopecuroides L. CMs 1 and 2 are new dimeric alkaloids whose piperidine matrine ring is cleaved and connected via the N'-1 bond. Their chemical structures have been confirmed by IR, UV, HR-ESI-MS, and NMR. Preliminary screening shows that they have topoisomerase I (Topo I)-based anti-tumor activity. Their Topo I inhibitory activities and mechanism have been evaluated by agarose gel electrophoresis assay and a molecular docking study. The results show that the inhibition rate of CM 1 is 82.26% at 1 mM concentration and that it exhibits significantly Topo I inhibitory activity. Further research has illustrated that CMs 1 and 2 exert inhibitory activity by stabilising the Topo I-DNA cleavage complex, implying that they have the potential to be developed as novel Topo I inhibitors.

Research Advances on Matrine

Matrine is an alkaloid extracted from traditional Chinese herbs including Sophora flavescentis, Sophora alopecuroides, Sophora root, etc. It has the dual advantages of traditional Chinese herbs and chemotherapy drugs. It exhibits distinct benefits in preventing and improving chronic diseases such as cardiovascular disease and tumors. The review introduced recent research progresses on extraction, synthesis and derivatization of Matrine. The summary focused on the latest research advances of Matrine on anti-atherosclerosis, anti-hypertension, anti-ischemia reperfusion injury, anti-arrhythmia, anti-diabetic cardiovascular complications, anti-tumor, anti-inflammatory, anti-bacterium, anti-virus, which would provide new core structures and new insights for new drug development in related fields.

Sustained Release of Co-Amorphous Matrine-Type Alkaloids and Resveratrol with Anti-COVID-19 Potential

Matrine (MAR), oxymatrine (OMAR), and sophoridine (SPD) are natural alkaloids with varying biological activities; matrine was recently used for the treatment of coronavirus disease 2019 (COVID-19). However, the short half-lives and rapid elimination of these matrine-type alkaloids would lead to low oral bioavailability and serious side effects. Herein, resveratrol (RES) was selected as a co-former to prepare their co-amorphous systems to improve the therapeutic index. The formation of co-amorphous MAR-RES, OMAR-RES, and SPD-RES was established through powder X-ray diffraction and modulated temperature differential scanning calorimetry. Furthermore, Fourier transform infrared spectroscopy and NMR studies revealed the strong molecular interactions between resveratrol and these alkaloids, especially OMAR-RES. Matrine, oxymatrine, and sophoridine in the co-amorphous systems showed sustained release behaviors in the dissolution experiments, due to the recrystallization of resveratrol on the surface of co-amorphous drugs. The three co-amorphous systems exhibited excellent physicochemical stability under high relative humidity conditions. Our study not only showed that minor structural changes of active pharmaceutical ingredients may have distinct molecular interactions with the co-former, but also discovered a new type of sustained release mechanism for co-amorphous drugs. This promising co-amorphous drug approach may present a unique opportunity for repurposing these very promising drugs against COVID-19.

Thermlanseedlines A-G, seven thermopsine-based alkaloids with antiviral and insecticidal activities from the seeds of Thermopsis lanceolata R. Br

Seven undescribed thermopsine-based alkaloids (1-7), including one undescribed biogenetically related intermediate (7), were isolated from the seeds of Thermopsis lanceolata R. Br. Compound 1 possessed a 6/6-6 tricyclic skeleton, while compounds 2-6 represented three rare dimerization patterns constructed by quinolizidine alkaloids. Their structures were elucidated by comprehensive spectroscopic data analysis as well as ECD calculations. Biologically, compound 6 displayed significant anti-Tomato spotted wilt virus (TSWV) activity compared with the positive control ningnanmycin. Moreover, compound 1 exhibited good insecticidal activity against Aphis fabae with LC₅₀ value of 25.2 mg/L.

The anti-neoplastic activities of aloperine in HeLa cervical cancer cells are associated with inhibition of the IL-6-JAK1-STAT3 feedback loop

Cervical cancer (CC) is recognized as the most common neoplasm in the female reproductive system worldwide. The lack of chemotherapeutic agents with outstanding effectiveness and safety severely compromises the anti-cipated prognosis of patients. Aloperine (ALO) is a natural quinolizidine alkaloid with marked anti-cancer effects on multiple malignancies as well as favorable activity in relieving inflammation, allergies and infection. However, its therapeutic efficacy and underlying mechanism in CC are still unclear. In the current study, MTT assay was employed to evaluate the viability of HeLa cells exposed to ALO to preliminarily estimate the effectiveness of ALO in CC. Then, the effects of ALO on the proliferation and apoptosis of HeLa cells were further investigated by plate colony formation and flow cytometry, respectively, while the migration and invasion of ALO-treated HeLa cells were evaluated using Transwell assay. Moreover, nude mice were subcutaneously inoculated with HeLa cells to demonstrate the anti-CC properties of ALO in vivo. The molecular mechanisms underlying these effects of ALO were evaluated by Western blot and immunohistochemical analysis. This study experimentally demonstrated that ALO inhibited the proliferation of HeLa cells via G2 phase cell cycle arrest. Simultaneously, ALO promoted an increase in the percentage of apoptotic HeLa cells by increasing the Bax/Bcl-2 ratio. Additionally, the migration and invasion of HeLa cells were attenuated by ALO treatment, which was considered to result from inhibition of epithelial-to-mesenchymal transition. For molecular mechanisms, the expression and activation of the IL-6-JAK1-STAT3 feedback loop were markedly suppressed by ALO treatment. This study indicated that ALO markedly suppresses the proliferation, migration and invasion and enhances the apoptosis of HeLa cells. In addition, these prominent anti-CC properties of ALO are associated with repression of the IL-6-JAK1-STAT3 feedback loop.

New heteroanalogs of tricyclic ascidian alkaloids: synthesis and biological activity

Heteroanalogs of ascidian alkaloids have been synthesized, and for the first time 10 different types of saturated carbo- and heteroannulated pyridones have been obtained. A new method for the formation of decahydro[1,3]oxazolo[2,3-j]quinoline and octahydro-5H-cyclopenta[b][1,3]oxazolo[3,2-a]pyridine was proposed. The synthesis of these heterocycles is based on the three-component cyclization of trifluoroacetoacetic ester and cycloketones with 1,2- and 1,3-dinucleophiles. It was found that reactions with amino alcohols are distinguished by the possibility of isolating carbocyclopyridones of various degrees of saturation. The diastereomeric structure of the synthesized heterocycles has been studied, and the mechanism of their formation has been proposed. Antitumor, anti-influenza and analgesic agents have been found among the synthesized compounds.

Genus Sophora: a comprehensive review on secondary chemical metabolites and their biological aspects from past achievements to future perspectives

Sophora is deemed as one of the most remarkable genera of Fabaceae, and the third largest family of flowering plants. The genus Sophora comprises approximately 52 species, 19 varieties, and 7 forms that are widely distributed in Asia and mildly in Africa. Sophora species are recognized to be substantial sources of broad spectrum biopertinent secondary metabolites namely flavonoids, isoflavonoids, chalcones, chromones, pterocarpans, coumarins, benzofuran derivatives, sterols, saponins (mainly triterpene glycosides), oligostilbenes, and mainly alkaloids. Meanwhile, extracts and isolated compounds from Sophora have been identified to possess several health-promising effects including anti-inflammatory, anti-arthritic, antiplatelets, antipyretic, anticancer, antiviral, antimicrobial, antioxidant, anti-osteoporosis, anti-ulcerative colitis, antidiabetic, anti-obesity, antidiarrheal, and insecticidal activities. Herein, the present review aims to provide comprehensive details about the phytochemicals and biological effects of Sophora species. The review spotlighted on the promising phytonutrients extracted from Sophora and their plethora of bioactivities. The review also clarifies the remaining gaps and thus qualifies and supplies a platform for further investigations of these compounds.

Double asymmetric intramolecular aza-Michael reaction: a convenient strategy for the synthesis of quinolizidine alkaloids

A new methodology to access the quinolizidine skeleton in an asymmetric fashion was devised. It involves two consecutive intramolecular aza-Michael reactions of sulfinyl amines bearing a bis-enone moiety, in turn generated by a monodirectional cross metathesis reaction. The sequence, which takes place with excellent yields and diastereocontrol, was applied to the total synthesis of alkaloids lasubine I and myrtine.

Phytotoxic Activity of Alkaloids in the Desert Plant Sophora alopecuroides

Sophora alopecuroides is known to produce relatively large amounts of alkaloids; however, their ecological consequences remain unclear. In this study, we evaluated the allelopathic potential of the main alkaloids, including aloperine, matrine, oxymatrine, oxysophocarpine, sophocarpine, sophoridine, as well as their mixture both in distilled H₂O and in the soil matrix. Our results revealed that all the alkaloids possessed inhibitory activity on four receiver species, i.e., Amaranthus retroflexus, Medicago sativa, Lolium perenne and Setaria viridis. The strength of the phytotoxicity of the alkaloids was in the following order: sophocarpine > aloperine > mixture > sophoridine > matrine > oxysophocarpine > oxymatrine (in Petri dish assays), and matrine > mixture > sophocarpine > oxymatrine > oxysophocarpine > sophoridine > aloperine (in pot experiments). In addition, the mixture of the alkaloids was found to significantly increase the IAA content, MDA content and POD activity of M. sativa seedlings, whereas CTK content, ABA content, SOD activity and CAT activity of M. sativa seedlings decreased markedly. Our results suggest S. alopecuroides might produce allelopathic alkaloids to improve its competitiveness and thus facilitate the establishment of its dominance; the potential value of these alkaloids as environmentally friendly herbicides is also discussed.

Uncommon Bis-Amide Matrine-type Alkaloids From Sophora alopecuroides With Anti-inflammatory Effects

Four new alkaloids (1–4) belonging to rare examples of bis-amide matrine-type were isolated from the seeds of sophora alopecuroides. Their structures including absolute configuration were determined by extensive spectroscopic analysis, electronic circular dichroism (ECD) interpretation, and X-ray diffraction crystallography. Chemically, bis-amide matrine-type alkaloids can provide new molecular template for structural modification. Compounds 3–4 displayed obvious anti-inflammatory effects based on the inhibition of two key pro-inflammatory cytokines [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6)] in a dose-dependent manner, with IC50 values from 35.6 to 45.8 μm.

Sophoridine Derivatives Induce Apoptosis and Autophagy to Suppress the Growth of Triple-Negative Breast Cancer through Inhibition of mTOR Signaling

In order to improve the antitumor potency and therapeutic margins of natural product sophoridine, its novel nitrogen mustard carbamate derivatives were designed and synthesized. In screening their in vitro activity, we found all the tested compounds were more potent against the highly aggressive triple-negative breast cancer cell line MDA-MB-231. Cellular functional assays showed that representative compounds could induce G1-phase arrest and trigger apoptosis, evidenced by the alteration of Bax, Bcl-2, caspase-3 and PARP levels. Furthermore, these compounds significantly enhanced the autophagic flux with increased expression of LC3-II and Beclin-1, as well as decreased level of p62, which may attribute to simultaneously inhibition of the phosphorylation of p70S6K, 4E-BP1 and AKT, the key substrates of the mTOR signaling pathway. In vivo, two compounds revealed potent antitumor activity in mice bearing MDA-MB-231. Altogether, our work describes novel leads to yield more potent chemotherapeutics against triple-negative breast cancers, possibly mesenchymal stem-like subtype.

Unraveling the Biosynthesis of Quinolizidine Alkaloids Using the Genetic and Chemical Diversity of Mexican Lupins

Quinolizidine alkaloids (QAs) are synthesized by the genus Lupinus as a defense against herbivores. Synthesis of QAs in lupins is species- and organ-specific. Knowledge about their biosynthesis and their corresponding pathways are still fragmentary, in part because lupins of commercial importance were mainly investigated, representing a small sample of the chemodiversity of the genus. Here, we explore the use of three Mexican lupins: Lupinus aschenbornii, Lupinus montanus, and Lupinus bilineatus as a model to study the physiology of QA biosynthesis. The corresponding QA patterns cover widely and narrowly distributed tetracyclic QAs. Quinolizidine alkaloid patterns of seeds and plantlets at different developmental stages were determined by GLC–MS and compared to identify the onset of de novo QA synthesis and to gain insight into specific and common biosynthesis trends. Onset of de novo QA biosynthesis occurred after the metabolization of seed QA during germination and was species-specific, as expected. A common QA pattern, from which the diversity of QA observed in these species is generated, was not found; however, lupanine and 3β-lupanine were found in the three specieswhile sparteine was not found in Lupinus bilineatus, suggesting that this simplest tetracyclic QA is not the precursor of more complex QAs. Similar patterns of metabolization and biosynthesis of structurally related QAs were observed, suggesting a common regulation.

Rapid screening of active components group with Topoisomerase I inhibitory activity in Sophora alopecuroides L. based on ultrafiltration coupled with UPLC-QTOF-MS

BACKGROUND

Topoisomerase I (Topo I) is a key target of many antitumor drugs in vivo. Alkaloids in Sophora alopecuroides L. can reportedly inhibit Topo I activity, but the pharmacodynamic material basis has not yet been determined.

OBJECTIVE

The objective of this study is to rapidly identify active components group which inhibit Topo I in S. alopecuroides L.

METHODS

Affinity ultrafiltration-ultra-performance liquid chromatography-quadrupole time of flight-mass spectrometry (UF-UPLC-QTOF-MS) screening system based on Topo I protein was established to screen and isolate a total alkaloid fraction in S. alopecuroides L. Topo I inhibitory activity and anti-tuomor proliferation activity of the screened components were evaluated, and their molecular mechanisms were studied.

RESULTS

Six compounds bound specifically to Topo I were obtained. Further screening showed that matrine, cytisine, and sophoridine presented higher inhibitory activity on Topo I and were able to inhibit the proliferation of breast cancer MDA-MB-468 cells with IC50 values of 9.40 ± 1.12 mM, 17.4 ± 2.20 mM and 10.4 ± 1.37 mM, respectively. To the best of our knowledge, their dual molecular mechanisms against Topo I have been discussed here for the first time: (1) stabilization of Topo I-DNA complex and (2) inhibition or blocking of Topo I binding to DNA.

CONCLUSION

Matrine, cytisine, and sophoridine from S. alopecuroides L. were defined as the active components group with Topo I inhibitory activity and their pharmacological mechanism was confirmed, which provided an important base for further research and development of antitumor components fromS. alopecuroides L.