Protopine and Allocryptopine Interactions with Plasma Proteins.

A comprehensive study of the interactions of human serum albumin (HSA) and α-1-acid glycoprotein (AAG) with two isoquinoline alkaloids, i.e., allocryptopine (ACP) and protopine (PP), was performed. The UV-Vis spectroscopy, molecular docking, competitive binding assays, and circular dichroism (CD) spectroscopy were used for the investigations. The results showed that ACP and PP form spontaneous and stable complexes with HSA and AAG, with ACP displaying a stronger affinity towards both proteins. Molecular docking studies revealed the preferential binding of ACP and PP to specific sites within HSA, with site 2 (IIIA) being identified as the favored location for both alkaloids. This was supported by competitive binding assays using markers specific to HSA's drug binding sites. Similarly, for AAG, a decrease in fluorescence intensity upon addition of the alkaloids to AAG/quinaldine red (QR) complexes indicated the replacement of the marker by the alkaloids, with ACP showing a greater extent of replacement than PP. CD spectroscopy showed that the proteins' structures remained largely unchanged, suggesting that the formation of complexes did not significantly perturb the overall spatial configuration of these macromolecules. These findings are crucial for advancing the knowledge on the natural product-protein interactions and the future design of isoquinoline alkaloid-based therapeutics.

Safety assessment of MPTA: An oral acute and 90-day sub-chronic toxicity study in Sprague-Dawley rats.

MPTA is a novel extract product derived from Macleaya cordata (Willd.) R. Br., which has good anti-inflammatory and antioxidant activity. The aim of this study was to investigate the acute oral toxicity and 90-day sub-chronic oral toxicity of MPTA. In the acute toxicity study, 50 SD rats of both sexes were randomly divided into 5 groups and dosed in a gradient from 197.53 mg/kg to 1000.00 mg/kg bw. Toxic effects were observed up to 14 days and LD50 was calculated. In a subchronic toxicity test, male and female SD rats were orally dosed repeatedly with 96.40, 19.28, 3.86 mg/kg bw of MPTA for 90 days. In addition, a control group was set up in the subchronic study. The acute toxicity test showed that the oral LD50 of MPTA was 481.99 mg/kg with a 95% confidence interval of 404.24-574.70 mg/kg. MPTA did not appear to induce toxic effects in the longer term in terms of food and water consumption, weight gain, haematological and clinical biochemical parameters and pathological examination. The first data on the potential toxicity of MPTA was provided to highlight the safety of short-term to longer-term oral administration of MPTA, and the experimental results yield and establish a NOEAL of 96.40 mg/kg/d for MPTA.

Synthesis and characterization of core-shell magnetic molecularly imprinted polymers for selective extraction of allocryptopine from the wastewater of Macleaya cordata (Willd) R. Br.

A novel type of magnetic molecularly imprinted polymers (MMIP) as the solid-phase extraction sorbent was prepared, which can extract effectively the allocryptopine from the waster of Macleaya cordata (Willd) R. Br. In this study, MMIP was synthesized by using Fe3 O4 @SiO2 , 4-vinyl-pyridine, ethylene glycol dimethacrylate, and allocryptopine, and these ingredients worked as magnetic core, functional monomer, cross-linker, and template, respectively. Concluded by the calculation of Gaussian 09 software, different ratio models of 4-vinyl-pyridine and allocryptopine were simulated, and the optimal ratio was 1:5 and the energy was -2205.34 kJ/mol. Transmission electron microscopy, vibration sample magnetometry, X-ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetric analysis were used to determine the morphology and structure of MMIP. Furthermore, the results of adsorption experiments indicated that MMIP had high selectivity, excellent recyclability, and good adsorption performance (9.86 mg/g, 298 K). The adsorption process was consistent with the Langmuir adsorption isotherm (R2 > 0.98, 298 K) and pseudo-second-order kinetics model (R2 > 0.99, 298 K). After six times adsorption-desorption experiments, the adsorption amount of MMIP only reduced to 8.5%. In the experiments of selective adsorption, MMIP has better adsorption properties for allocryptopine (ALL, C21 H23 NO5 ) than those having the same functional group. The limit of detection (LOD) was 0.4 µg/mL. The relative standard deviation ranged from 0.09% to 0.72%. The recovery of allocryptopine in samples ranged from 93.60% to 106.19%. In addition, the synthesized complex had a certain adsorption effect on allocryptopine separating from the wastewater of Macleaya cordata (Willd) R. Br.

Exploring allocryptopine as a neuroprotective agent against oxidative stress-induced neural apoptosis via Akt/GSK-3ß/tau pathway modulation.

Alzheimer's disease (AD) is characterized by neuronal loss due to hyperphosphorylated proteins induced by oxidative stress. AD remains a formidable challenge in the medical field, as current treatments focusing on single biomarkers have yielded limited success. Hence, there's a burgeoning interest in investigating novel compounds that can target mechanisms, offering alternative therapeutic approaches. The aim of this study is to investigate the effects of allocryptopine, an isoquinoline alkaloid, on mechanisms related to AD in order to develop alternative treatment strategies. In this study, the in vitro AD cell model was obtained by inducing nerve growth factor (NGF)-differentiated PC12 (dPC12) cells to oxidative stress with H2O2, and also the effect mechanism of different allocryptopine concentrations on the in vitro AD cell model was studied. The treatments' antioxidative effects at the ROS level and their regulation of the cell cycle were assessed through flow cytometry, while their anti-apoptotic effects were evaluated using both flow cytometry and qRT-PCR. Additionally, the phosphorylation levels of Akt, GSK-3ß, and tau proteins were analyzed via western blot, and the interactions between Akt, GSK-3ß, CDK5 proteins, and allocryptopine were demonstrated through molecular docking. Our study's conclusive results revealed that allocryptopine effectively suppressed intracellular ROS levels, while simultaneously enhancing the Akt/GSK-3ß signaling pathway by increasing p-Akt and p-GSK-3ß proteins. This mechanism played a critical role in inhibiting neural cell apoptosis and preventing tau hyperphosphorylation. Moreover, allocryptopine demonstrated its ability to regulate the G1/S cell cycle progression, leading to cell cycle arrest in the G1 phase, and facilitating cellular repair mechanisms, potentially contributing to the suppression of neural apoptosis. The in silico results of allocryptopine were shown to docking with the cyclin-dependent kinase 5 (CDK 5) playing a role in tau phosphorylation Akt and GSK-3ß from target proteins. Therefore, the in silico study results supported the in vitro results. The results showed that allocryptopine can protect dPC12 cells from oxidative stress-induced apoptosis and hyperphosphorylation of the tau protein by regulating the Akt/GSK-3ß signaling pathway. Based on these findings, it can be suggested that allocryptopine, with its ability to target biomarkers and its significant effects on AD-associated mechanisms, holds promise as a potential candidate for drug development in the treatment of AD. Further research and clinical trials are recommended in the future.

Anti-Inflammatory Effects of Allocryptopine via the Target on the CX3CL1-CX3CR1 axis/GNB5/AKT/NF-κB/Apoptosis in Dextran Sulfate-Induced Mice.

Allocryptopine (ALL) is an isoquinoline alkaloid extracted from Macleaya cordata(Willd). R. Br., which has been claimed to have anti-inflammatory and neuroprotection properties. However, the mechanism by which ALL ameliorates inflammatory bowel disease (IBD) remains unclear. Here, we used network pharmacology and quantitative proteomic approaches to investigate the effect of ALL on IBD pathogenesis. Network pharmacology predicted potential targets and signaling pathways of ALL's anti-IBD effects. As predicted by network pharmacology, gene ontology (GO) analysis, in terms of the proteomic results, showed that the immune response in mucosa and antimicrobial humoral response were enriched. Further study revealed that the ALL-related pathways were the chemokine signaling pathway and apoptosis in the Kyoto Encyclopedia of Genes and Genomes (KEGG). In addition, we identified AKT1 as a hub for the critical pathways through protein-protein interaction (PPI) network analysis. Similar to mesalazine (MES), Western blot verified that ALL downregulated upstream chemokine CX3CL1 and GNB5 content to reduce phosphorylation of AKT and NF-κB, as well as the degree of apoptosis, to improve inflammatory response in the colon. Our research may shed light on the mechanism by which ALL inhibits the CX3CL1/GNB5/AKT2/NF-κB/apoptosis pathway and improves the intestinal barrier to reduce colitis response and act on the CX3CL1-CX3CR1 axis to achieve neuroprotection.

Neuroprotective effects of allocryptopine-rich alkaloid extracts against oxidative stress-induced neuronal damage.

BACKGROUND: Oxidative stress is a significant feature in the pathomechanism of neurodegenerative diseases. Thus, the search for an effective and safe novel antioxidant agent with neuroprotective properties has increased the interest in medicinal plant products as a bioactive phytochemical source. However, little is known about the potential effects of the medically important Glaucium corniculatum as a natural antioxidant. OBJECTIVE: In the present study, it was aimed to investigate the anti-oxidative, anti-apoptotic, and cell cycle regulatory mechanisms underlying the neuroprotective effects of alkaloid extracts (chloroform, methanol, and water) from G. corniculatum, which was profiled for major alkaloid/alkaloids, against H2O2-induced neuronal damage in differentiated PC12 cells. MATERIALS AND METHODS: The profiles of the alkaloid extracts were analyzed by GC-MS. The effects of the alkaloid extracts on intracellular ROS production, level of apoptotic cells, and cell cycle dysregulation were analyzed by flow cytometry; the effects on mRNA expression of apoptosis-related genes were also analyzed by qRT-PCR. RESULTS: The same alkaloid components, allocryptopine, tetrahydropalmatine, and tetrahydroberberine N-oxide were obtained in all three solvents, but the ratios of the components differed according to the solvents. Allocryptopine was determined to be the major alkaloid ingredient in the alkaloid extracts, with the highest amount of allocryptopine (497 µg/mg) being found in the chloroform alkaloid extract (CAE) (*p < 0.05). The best results were obtained from CAE, which has the highest amount of allocryptopine among alkaloid extracts in all studies. CAE suppressed intracellular ROS production (5.7-fold), percentage of apoptotic cells (3.0-fold), and cells in the sub G1 phase (6.8-fold); additionally, it increased cells in the G1 phase (1.5-fold) (**p < 0.01). CAE remarkably reduced the expressions of Bax, Caspase-9/-3 mRNA (2.4-3.5-fold) while increasing the expression of Bcl-2 mRNA (3.0-fold) (*p < 0.05). CONCLUSIONS: Our results demonstrated that alkaloid extracts from G. corniculatum, which contain allocryptopine, tetrahydropalmatine, and tetrahydroberberine N-oxide suppressed oxidative stress-induced neuronal apoptosis, possibly by suppressing the mitochondrial apoptotic pathway and regulating the cell cycle. These results are the first report that related alkaloids have played a neuroprotective role by regulating multiple mechanisms. Thus, our study indicated that these alkaloids especially allocryptopine could offer an efficient and novel strategy to explore novel drugs for neuroprotection and cognitive improvement.

Anticancer effects of NSC­631570 (Ukrain) in head and neck cancer cells: In vitro analysis of growth, invasion, angiogenesis and gene expression.

NSC­631570 (Ukrain) is an aqueous extract of Chelidonium majus, a herbaceous perennial plant, one of two species in the genus Chelidonium, which has been demonstrated to selectively kill tumor cells without affecting non­malignant cells. In the present study, the components of NSC­631570 were examined by combined liquid chromatography/mass spectroscopy (LC­MS) and the effects of NSC­631570 on HNSCC cell lines, as well as primary cells, were analyzed with respect to growth, apoptosis, invasion, angiogenesis and gene expression. LC­MS identified chelerythrine and allocryptopine as the major alkaloids of the extract. Moreover, NSC­631570 suppressed the growth of all tested HNSCC cell lines, including a paclitaxel­resistant and P­glycoprotein (MDR1)­overexpressing cell line. Mucosal keratinocytes were also affected by the extract, while fibroblasts proved to be much more resistant. In contrast to allocryptopine, chelerythrine had toxic effects on HNSCC cell lines at low doses. NSC­631570 significantly induced apoptosis in the FaDu and HLaC78 cell lines. As analyzed by a spheroid­based invasion assay, cell migration was significantly suppressed by NSC­631570 in FaDu cells on gelatine, fibronectin, collagen, laminin and Matrigel®. Migration of the highly invasive cell line HLaC78 was also inhibited, albeit to a lesser extent (not significant on laminin). Microarray analysis revealed the downregulation of genes encoding key regulators, including EGFR, AKT2, JAK1, STAT3 and ß­catenin (CTNNB1), all of which are involved in cell proliferation, migration, angiogenesis, apoptosis as well as the radiation­ and chemo­resistance of HNSCC. The strongest upregulation occurred for cytochrome P450 1A1 (CYP1A1) and 1B1 (CYP1B1), involved in the metabolism of xenobiotics. Upregulation of CYP1A1 was at least partially caused by chelerythrine and allocryptopine, as shown by RT­qPCR in two HNSCC cell lines. In addition, NSC­631570 showed a high anti­angiogenic action on the tube formation ability of human umbilical vein endothelial cells (HUVECs). In conclusion, this study highlights NSC­631570 as a promising therapeutic approach for HNSCC.

Allocryptopine: A Review of Its Properties and Mechanism of Antiarrhythmic Effect.

Abstract：Throughout the last decade, extensive efforts have been devoted to developing a percutaneous catheter ablation and implantable cardioverter-defibrillator technique for patients suffering from ventricular arrhythmia. Antiarrhythmic drug efficacy for preventing arrhythmias remains disappointing because of adverse cardiovascular effects. Allocryptopine is an isoquinoline alkaloid widely present in medicinal herbs. Studies have indicated that allocryptopine exhibits potential anti-arrhythmic actions in various animal models. The potential therapeutic benefit of allocryptopine in arrhythmia diseases is addressed in this study, focusing on multiple ion channel targets and reduced repolarization dispersion. The limitations of allocryptopine research are clear given a lack of parameters regarding toxicology and pharmacokinetics and clinical efficacy in patients with ventricular arrhythmias. Much remains to be revealed about the properties of allocryptopine.

Change in late sodium current of atrial myocytes in spontaneously hypertensive rats with allocryptopine treatment.

AIM: We aimed to study the effect of allocryptopine (All) on the late sodium current (INa,Late) of atrial myocytes in spontaneously hypertensive rats (SHR). METHODS: The enzyme digestion method was used to separate single atrial myocytes from SHR and Wistar-Kyoto (WKY) rats. INa,Late was recorded using the patch-clamp technique, and the effect of All was evaluated on the current. RESULTS: Compared with WKY rat cells, an increase in the INa,Late current in SHR myocytes was found. After treatment with 30 µM All, the current densities were markedly decreased; the ratio of INa,Late/INa,peak of SHR was reduced by 30 µM All. All reduced INa,Late by alleviating inactivation of the channel and increasing the window current of the sodium channel. Furthermore, INa,Late densities of three SCN5A mutations declined substantially with 30 µM All in a concentration-dependent manner. CONCLUSIONS: The results clearly show that an increase in INa,Late in SHR atrial myocytes was inhibited by All derived from Chinese herbal medicine.

Rapid identification of "mad honey" from Tripterygium wilfordii Hook. f. and Macleaya cordata (Willd) R. Br using UHPLC/Q-TOF-MS.

Cases of honey poisoning have been reported widely, meaning there is a need for methods that detect "mad honey" or honey contaminated with plant-derived toxins to protect human health. In this study, we compared whole flower extracts and honey from Tripterygium wilfordii Hook. f. (TwHf) and Macleaya cordata (Willd) R. Br (McRB) using QuEChERS (quick, easy, cheap, effective, rugged, and safe) and ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS). The results revealed several compounds common to whole flowers and honey samples. Triptolide and protopine were selected as potential markers for identifying "mad honeys" from these plants. The developed method can easily detect different honey varieties that were spiked with 5% TwHf and McRB honey samples. Additionally, 90 commercial honey samples were analyzed and determined as free from contamination. The method described in this report could be useful for studies on honey from other poisonous nectar and pollen plants.

Effects of allocryptopine on outward potassium current and slow delayed rectifier potassium current in rabbit myocardium.

OBJECTIVE: Allocryptopine (ALL) is an effective alkaloid of Corydalis decumbens (Thunb.) Pers. Papaveraceae and has proved to be anti-arrhythmic. The purpose of our study is to investigate the effects of ALL on transmural repolarizing ionic ingredients of outward potassium current (I to) and slow delayed rectifier potassium current (I Ks). METHODS: The monophasic action potential (MAP) technique was used to record the MAP duration of the epicardium (Epi), myocardium (M) and endocardium (Endo) of the rabbit heart and the whole cell patch clamp was used to record I to and I Ks in cardiomyocytes of Epi, M and Endo layers that were isolated from rabbit ventricles. RESULTS: The effects of ALL on MAP of Epi, M and Endo layers were disequilibrium. ALL could effectively reduce the transmural dispersion of repolarization (TDR) in rabbit transmural ventricular wall. ALL decreased the current densities of I to and I Ks in a voltage and concentration dependent way and narrowed the repolarizing differences among three layers. The analysis of gating kinetics showed ALL accelerated the channel activation of I to in M layers and partly inhibit the channel openings of I to in Epi, M and Endo cells. On the other hand, ALL mainly slowed channel deactivation of I Ks channel in Epi and Endo layers without affecting its activation. CONCLUSIONS: Our study gives partially explanation about the mechanisms of transmural inhibition of I to and I Ks channels by ALL in rabbit myocardium. These findings provide novel perspective regarding the anti-arrhythmogenesis application of ALL in clinical settings.

Application of BACE1 immobilized enzyme reactor for the characterization of multifunctional alkaloids from Corydalis cava (Fumariaceae) as Alzheimer's disease targets.

In our ongoing study focused on Corydalis cava (Fumariaceae), used in folk medicine in the treatment of memory dysfunctions, we have investigated fifteen previously isolated alkaloids for their potential multifunctional activity on Alzheimer's disease (AD) targets. Determination of ß-site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibition was carried out using a BACE1-Immobilized Enzyme Reactor (IMER) by validating the assay with a multi-well plate format Fluorescence Resonance Energy Transfer (FRET) assay. Seven alkaloids out of fifteen were found to be active, with (-)-corycavamine (3) and (+)-corynoline (5) demonstrating the highest BACE1 inhibition activity, in the micromolar range, in a concentration dependent manner. BACE1-IMER was found to be a valid device for the fast screening of inhibitors and the determination of their potency. In a permeation assay (PAMPA) for the prediction of blood-brain barrier (BBB) penetration, the most active compounds, (-)-corycavamine (3) and (+)-corynoline (5), were found to be able to cross the BBB. Not all compounds showed activity against glycogen synthase kinase-3ß (GSK-3ß) and casein kinase-1δ (CK-1δ). On the basis of the reported results, we found that some C. cava alkaloids have multifunctional activity against AD targets (prolyl oligopeptidase, cholinesterases and BACE1). Moreover, we tried to elucidate the treatment effectivity (rational use) of its extract in memory dysfunction in folk medicine.

Electrophysiological and trafficking defects of the SCN5A T353I mutation in Brugada syndrome are rescued by alpha-allocryptopine.

Brugada syndrome (BrS), which causes arrhythmias that lead to sudden cardiac death, is linked to loss-of-function mutations that affect sodium channels. Here, we investigate the rescue effect of alpha-allocryptopine (All) from Chinese herbal medicine in a T353I mutation of SCN5A, which combines trafficking abnormalities with Brugada syndrome. SCN5A-T353I expressed in HEK293 cells showed a small peak current (I(peak)) of only 59.6% of WT and an observably sustained current (I(sus)). We found that All strongly enhanced the I(peak) of the T353I channel by enhancing the plasma membrane (PM) expression of Nav1.5 and rescued defective trafficking after co-incubation with HEK293 cells that carry mutation channel 24 h. It is also beneficial to increase the I(peak) of the T353I mutation by All by prolonging the closed-state inactivation (CSI) process and shortening the recovery from inactivation of the T353I mutation. Interestingly, the I(sus) of T353I was significantly inhibited by All, which reduces the occurrence of LQT syndrome 3 (LQT3). We provide evidence that All can rescue the trafficking deficiencies and restore the cellular electrophysiological characteristics of SCN5A-T353I. This feature of All may benefit patients with the BrS-associated Nav1.5 channel and might have other potential therapeutic effects.

Fingerprint profiling of Macleaya cordata fruits from different regions / 中草药

Objective To establish the fingerprint profiling of fruits of Macleaya cordata and study the method for its quality evaluation. Methods The fingerprint profiling of M. cordata fruits from different regions was established using high performance liquid chromatography (HPLC) based on the local standard which was the determination method of the content of protopine, allocryptopine, sanguinarine, and chelerythrine from Changsha of Hunan Province in 2009. The principal component analysis (PCA) and cluster analysis (CA) were performed to explore the correlation among the common fingerprint peaks, origins, and quality of M. cordata fruits. Results Eleven common fingerprint peaks were identified in the fingerprint profiling of chemical constituents of M. cordata fruits from different regions. M. cordata fruits produced from eight areas were classified into two classes by PCA and CA method, and there were five common peaks, including peak 5, 7, 8, 9, and 11 with significant contribution on the regional difference of the fingerprint. Also, common peak 6 was the right peak as the reference peak because of its less variation, appropriate retention time and intensity. Conclusion The fingerprint profiling of chemical constituents of M. cordata fruits established in this study has good precision, repeatability, and stability, which can be used to evaluate the quality of fruits of M. cordata from different producing areas.

Chemical constituents of Corydalis decumbens / 中草药

Objective: To study the alkaloids chemical composition from stem of Corydalis decumbens. Methods: The compounds from the ethyl acetate part were separated and purified through various kinds of chromatographic methods and their structures were identified by physico-chemical properties of spectroscopic methods. Results: Eleven alkaloids compounds were isolated and identified. They were protopine (1), muramine (2), β-allocryptopine (3), cryptopine (4), (6S, 6aS, M)-isocorydine (5), bulbocapine (6), (+)-egenine (7), (-)-corypalmine (8), bicuculline (9), (-)-7'-O-methylegenine (10), and epi-coryximine (11). Conclusion: Compounds 5 and 10 are isolated from this genus for the first time. Compound 3, 8, and 10 are isolated from this plant for the first time.

Effect of allocryptopine on antagonizing hepatic fibrosis / 中草药

Objective: To investigate the prophylactic and therapeutic effects of allocryptopine on experimental hepatic fibrosis. Methods: Experimental hepatic fibrosis models were induced by injection of tetrachloride in combination with the drinking of 5% alcohol to rats and Schistosoma japomicum infection to mice. The effects of allocryptopine anti-hepatic fibrosis were evaluated by comparing the liver and spleen indexes, tissue biochemical indices (ALT, AST), lipid peroxidation indices (GSH-Px, MDA, SOD), serum fibrosis indices (HA, PCIII LN), the expression level of Hyp and collagen type I, III (CoI, CoIII), and the liver pathology before and after allocryptopine intervention. Results: In CCl 4-induced liver fibrosis model rats, compared with model group, the liver index and the expression level of CoI were obviously decreased in allocryptopine prophylactic groups (P<0.05, 0.01), high-dose prophylactic allocryptopine could significantly reduce the expression level of CoIII (P<0.01), middle-dose prophylactic allocryptopine could obviously reduce the spleen index, the content of AST (P<0.05); in allocryptopine therapeutic group, the liver index, the content of ALT, and the expression level of CoIII were significantly decreased (P<0.05, 0.01). In S. japomicum-induced liver fibrosis model mice, prophylactic allocryptopine could reduce the content of ALT and the expression level of Hyp (P<0.05); the liver index, the contents of PCIII, HA, and ALT were significantly decreased in high-dose allocryptopine therapeutic group (P<0.05, 0.01), the liver index, the contents of PCIII, and HA were obviously decreased in middle-dose allocryptopine therapeutic group (P<0.05); In addition, the hepatic histopathology was also improved in varying degrees after allocryptopine intervention. Conclusion: Allocryptopine has certain effects on anti-injury for hepatocyte, ameliorating liver function, and prohibiting hepatic fibrosis.