A review on phytochemistry, pharmacology and toxicology studies of Aconitum

Detoxification and underlying mechanisms towards toxic alkaloids by Traditional Chinese Medicine processing: A comprehensive review

BACKGROUND

Alkaloids have attracted enduring interest worldwide due to their remarkable therapeutic effects, including analgesic, anti-inflammatory, and anti-tumor properties, thus offering a rich source for lead compound design and new drug discovery. However, some of these alkaloids possess intrinsic toxicity. Processing (Paozhi) is a pre-treatment step before the application of herbal medicines in traditional Chinese medicine (TCM) clinics, which has been employed for centuries to mitigate the toxicity of alkaloid-rich TCMs.

PURPOSE

To explore the toxicity phenotypes, chemical basis, mode of action, detoxification processing methods, and underlying mechanisms, we can gain crucial insights into the safe and rational use of these toxic alkaloid-rich herbs. Such insights have the great potential to offer new strategies for drug discovery and development, ultimately improving the quality of life for millions of people.

METHODS

Literatures published or early accessed until December 31, 2023, were retrieved from databases including PubMed, Web of Science, and CNKI. The following keywords, such as "toxicity", "alkaloid", "detoxification", "processing", "traditional Chinese medicine", "medicinal plant", and "plant", were used in combination or separately for screening.

RESULTS

Toxicity of alkaloids in TCM includes hepatotoxicity, nephrotoxicity, neurotoxicity, cardiotoxicity, and other forms of toxicity, primarily induced by pyrrolizidines, quinolizidines, isoquinolines, indoles, pyridines, terpenoids, and amines. Factors such as whether the toxic-alkaloid enriched part is limited or heat-sensitive, and whether toxic alkaloids are also therapeutic components, are critical for choosing appropriate detoxification processing methods. Mechanisms of alkaloid detoxification includes physical removal, chemical decomposition or transformation, as well as biological modifications.

CONCLUSION

Through this exploration, we review toxic alkaloids and the mechanisms underlying their toxicity, discuss methods to reduce toxicity, and unravel the intricate mechanisms behind detoxification. These offers insights into the quality control of herbs containing toxic alkaloids, safe and rational use of alkaloid-rich TCMs in clinics, new strategies for drug discovery and development, and ultimately helping improve the quality of life for millions of people.

Investigations on the morpho-anatomy and histochemistry of Aconitum napellus L

Aconitum napellus L. is a popular medicinal plant extensively used in homeopathy. This article provides detailed morphology and microscopy, including the anatomical and histochemical features of the herb, to aid authentication and quality control. In cross-section, the root in secondary growth shows the phloem surrounded by pericyclic fibers and a well-developed xylem. The stem is irregular in outline, displaying unicellular trichomes and many free collateral vascular bundles encircling the pith. The leaf is dorsiventral, hypostomatic with anomocytic and anisocytic stomata, and shows non-glandular trichomes. The floral parts are characterized by uniseriate epidermises, homogeneous mesophyll, anomocytic stomata on the abaxial surface, trichomes, and oval pollen grains. The tissue fragments in powdered herbs show these characteristics and have numerous starch grains with thimble-shaped, linear or star-shaped hilum. The detailed macroscopic and microscopic analysis provided in this study can help in the authentication and quality control of A. napellus raw materials. RESEARCH HIGHLIGHTS: Key anatomical, micromorphological, and microchemical features of Aconitum napellus are described. The results of the study can support the taxonomy of the genus Aconitum. Morphological standardization of the species reported here is helpful in the quality control of this herb.

Anti-rheumatic potential vis-à-vis aconitine and hypaconitine content analysis in different Aconitum spp. from Sikkim Himalayas (India)

Aconitum spp. are important medicinal plants mentioned in Ayurveda as Ativisa or Vatsanabha. The present study aims to evaluate anti-rheumatic potential in seven Aconitum species and correlation with aconitine and hypaconitine content. Anti-rheumatic potential was analyzed through in vitro xanthine oxidase inhibition, anti-inflammatory and ROS scavenging assays; and quantification of aconitine and hypaconitine with RP-HPLC method validated as per ICH guidelines. The findings reveal that A. palmatum possessed the most promising response (IC50 =12.68±0.15 μg/ml) followed by A. ferox (IC50 =12.912±1.87 μg/ml) for xanthin oxidase inhibition. We observed a wide variation in aconitine and hypaconitine content ranging from 0.018 %-1.37 % and 0.0051 %-0.077 % respectively on dry weight basis. Aconitine and hypaconitine showed moderate positive correlation (r=0.68 and 0.59 respectively) with anti-rheumatic potential. The study identifies potential alternative species of Aconitum that can help in sustainable availability of quality raw material.

Aconitine and its derivatives: bioactivities, structure-activity relationships and preliminary molecular mechanisms

Aconitine (AC), which is the primary bioactive diterpene alkaloid derived from Aconitum L plants, have attracted considerable interest due to its unique structural feature. Additionally, AC demonstrates a range of biological activities, such as its ability to enhance cardiac function, inhibit tumor growth, reduce inflammation, and provide analgesic effects. However, the structure-activity relationships of AC are remain unclear. A clear understanding of these relationships is indeed critical in developing effective biomedical applications with AC. In line with these challenges, this paper summarized the structural characteristics of AC and relevant functional and bioactive properties and the structure-activity relationships presented in biomedical applications. The primary temporal scope of this review was established as the period spanning from 2010 to 2023. Subsequently, the objective of this review was to provide a comprehensive understanding of the specific action mechanism of AC, while also exploring potential novel applications of AC derivatives in the biomedical field, drawing upon their structural characteristics. In conclusion, this review has provided a comprehensive analysis of the challenges and prospects associated with AC in the elucidation of structure-bioactivity relationships. Furthermore, the importance of exploring modern biotechnology approaches to enhance the potential biomedical applications of AC has been emphasized.

A new C19-diterpenoid alkaloid in Aconitum georgei Comber

Nine diterpenoid alkaloids were isolated from Aconitum georgei Comber belonging to the genus Aconitum in Ranunculaceae family. Their structures were determinated by using HR-ESI-MS and 1 D/2D NMR spectra as geordine (1), yunaconitine (2), chasmanine (3), crassicauline A (4), forestine (5), pseudaconine (6), 14-acetylalatisamine (7), austroconitine B (8), and talatisamine (9). Among them, compound 1 is a previously undescribed aconitine-type C19-diterpenoid alkaloid, and compounds 3, and 5-9 have not previously been isolated from this species. The results of in vitro experiments indicated that new compound 1 possesses mild anti-inflammatory activity, which inhibited the production of NO in LPS-activated RAW 264.7 cells with an inhibition ratio of 29.75% at 50 μM.

Recurrent malignant ventricular arrhythmias and paresthesia-a mystery revealed as aconitine poisoning: a case report

BACKGROUND

We report a case of a clinical challenge lasting for 12 months, with severe and unresolved clinical features involving several medical disciplines.

CASE PRESENTATION

A 53-year-old Caucasian male, who had been previously healthy apart from a moderate renal impairment, was hospitalized 12 times during a 1-year period for a recurrent complex of neurological, cardiovascular, and gastrointestinal symptoms and signs, without any apparent etiology. On two occasions, he suffered a cardiac arrest and was successfully resuscitated. Following the first cardiac arrest, a cardiac defibrillator was inserted. During the 12th admission to our hospital, aconitine poisoning was suspected after a comprehensive multidisciplinary evaluation and confirmed by serum and urine analyses. Later, aconitine was also detected in a hair segment, indicating exposure within the symptomatic period. After the diagnosis was made, no further episodes occurred. His cardiac defibrillator was later removed, and he returned to work. A former diagnosis of epilepsy was also abandoned. Criminal intent was suspected, and his wife was sentenced to 11 years in prison for attempted murder. To make standardized assessments of the probability for aconitine poisoning as the cause of the eleven prior admissions, an "aconitine score" was established. The score is based on neurological, cardiovascular, gastrointestinal, and other clinical features reported in the literature. We also make a case for the use of hair analysis to confirm suspected poisoning cases evaluated after the resolution of clinical features.

CONCLUSION

This report illustrates the medical challenge raised by cases of covert poisoning. In patients presenting with symptoms and signs from several organ systems without apparent cause, poisoning should always be suspected. To solve such cases, insight into the effects of specific toxic agents is needed. We present an "aconitine score" that may be useful in cases of suspected aconitine poisoning.

Multi-omics analysis reveals the evolutionary origin of diterpenoid alkaloid biosynthesis pathways in Aconitum

Diterpenoid alkaloids (DAs) have been often utilized in clinical practice due to their analgesic and anti-inflammatory properties. Natural DAs are prevalent in the family Ranunculaceae, notably in the Aconitum genus. Nevertheless, the evolutionary origin of the biosynthesis pathway responsible for DA production remains unknown. In this study, we successfully assembled a high-quality, pseudochromosome-level genome of the DA-rich species Aconitum vilmorinianum (A. vilmorinianum) (5.76 Gb). An A. vilmorinianum-specific whole-genome duplication event was discovered using comparative genomic analysis, which may aid in the evolution of the DA biosynthesis pathway. We identified several genes involved in DA biosynthesis via integrated genomic, transcriptomic, and metabolomic analyses. These genes included enzymes encoding target ent-kaurene oxidases and aminotransferases, which facilitated the activation of diterpenes and insertion of nitrogen atoms into diterpene skeletons, thereby mediating the transformation of diterpenes into DAs. The divergence periods of these genes in A. vilmorinianum were further assessed, and it was shown that two major types of genes were involved in the establishment of the DA biosynthesis pathway. Our integrated analysis offers fresh insights into the evolutionary origin of DAs in A. vilmorinianum as well as suggestions for engineering the biosynthetic pathways to obtain desired DAs.

Identification and quality evaluation of different processed products of Aconitum carmichaelii by ultra-high-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry and ultra-high-performance liquid chromatography-tandem mass spectrometry

Aconitum carmichaelii is widely used to treat chronic and intractable diseases due to its remarkable curative effect, but it is also a highly toxic herb with severe cardiac and neurotoxicity. It has been combined with honey for thousands of years to reduce toxicity and enhance efficacy, but there has been no study on the chemical constituent changes in the honey-processing so far. In this study, the chemical constituents of A. carmichaelii before and after honey-processing were characterized by ultra-high-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry. The results showed that a total of 118 compounds were identified, of which six compounds disappeared and five compounds were newly produced after honey-processing, and the cleavage pathway of main components was elucidated. At the same time, 25 compounds were found to have significant effects on different products, among which four compounds with the biggest difference were selected for quantitative analysis by ultra-high-performance liquid chromatography-tandem mass spectrometry. This study not only explained the chemical differences between the different products, but also helped to control the quality of the honey-processed products more effectively, and laid a foundation for further elucidating the mechanism of chemical constituent change during the honey-processing of A. carmichaelii.

Mechanism of aconitine mediated neuronal apoptosis induced by mitochondrial calcium overload caused by MCU

Aconitine is a crucial toxic component in Chinese herbal medicines such as Aconitum, Aconitum coreanum, and Aconitum soongaricum. The poisoning symptoms of the central nervous system and cardiovascular system caused by it are relatively common in China, and there are many studies on cardiovascular system diseases caused by aconitine. However, the specific mechanism of neurotoxicity induced by aconitine is still unclear. This study explored the effect and mechanism of mitochondrial calcium uniporter on mitochondrial energy metabolism disorder in aconitine poisoning hippocampal neurons. The results showed that after treatment with 400μmol/L aconitine, mitochondrial energy metabolism was abnormal in rat hippocampal neuron cells, the expression of MCU in mitochondria was up-regulated, calcium overload in mitochondria, ATP production decreased, and mitochondrial membrane potential Changes, increased expression of the apoptosis gene Cleaved-Caspase-3. After treatment with the MCU agonist spermine, mitochondrial energy metabolism was significantly abnormal, and cell apoptosis was increased considerably. However, pretreatment with calcium ion channel inhibitor Ruthenium Red (RR) effectively promoted the generation of ATP, thereby improving mitochondrial energy metabolism disorders and reducing cell apoptosis. These results suggest that aconitine induces mitochondrial energy metabolism dysfunction in hippocampal neurons, which may be related to the increased expression of MCU.

The known, unknown, and the intriguing about members of a critically endangered traditional medicinal plant genus Aconitum

Humanity will always be indebted to plants. In the ongoing scientific era, the 'Herbal Revolution' has helped discover several valuable medicinal plants and associated novel secondary metabolites from the diverse unexplored ecosystems, treating several diseases via phytotherapy. The Aconitum genus comprises several economically-important poisonous mountainous medicinal plant species whose unique biodiversity is on the verge of extinction due to illegal human intervention triggered habitat loss, over-harvesting, and unrestricted trading. Owing to its vast diversity of diterpene alkaloids, most species are extensively used to treat several ailments in rural parts of the world. Irrespective of this, many unexplored and intriguing prospects exist to understand and utilize this critical plant for human benefit. This systematic review tries to fill this gap by compiling information from the sporadically available literature known for ~300 Aconitum spp. regarding its nomenclature and classification, endangerment, plant morphology, ploidy, secondary metabolites, drug pharmacokinetics, conservation, and omics-based computational studies. We also depicted the disparity in the studied model organisms for this diverse genus. The absence of genomic/metagenomic data is becoming a limiting factor in understanding its plant physiology, metabolic pathways, and plant-microbes interactions, and therefore must be promoted. Additionally, government support and public participation are crucial in establishing conservation protocols to save this plant from endangerment.

A review on efforts for improvement in medicinally important chemical constituents inAconitum through biotechnological interventions

The genus Aconitum belongs to the family Ranunculaceae, is endowed with more than 350 species on the earth. Medicinally important aconitine type of diterpenoid alkaloids are the characteristic compounds in most of the Aconitum species. The present review endeavored the major research carried out in the field of genetic resource characterization, pharmacological properties, phytochemistry, major factors influencing quantity, biosynthetic pathways and processing methods for recovery of active ingredients, variety improvement, propagation methods, and important metabolite production through cell/organ culture of various Aconitum species. More than 450 derivatives of aconitine-type C19 and C20-diterpenoid alkaloids along with a few other non-alkaloidal compounds, such as phenylpropanoids, flavonoids, terpenoids, and fatty acids, have been identified in the genus. A few Aconitum species and their common diterpenoid alkaloid compounds are also well characterized for analgesic, inflammatory and cytotoxic properties. However, the different isolated compound needs to be validated for supporting other traditional therapeutical uses of the plant species. Aconitine alkaloids shared common biosynthesis pathway, but their diversification mechanism remains unexplored in the genus. Furthermore, the process needs to be developed on secondary metabolite recovery, mass-scale propagation methods, and agro-technologies for maintaining the quality of products. Many species are losing their existence in nature due to over-exploitation or anthropogenic factors; thus, temporal monitoring of the population status in its habitat, and suitable management programs for ascertaining conservation needs to be developed.

Synthesis, Pharmacological Evaluation, and Molecular Modeling of Lappaconitine-1,5-Benzodiazepine Hybrids

Diterpenoid alkaloids, originating from the amination of natural tetracyclic diterpenes, have long interested scientists due to their medicinal uses and infamous toxicity which has limited the clinical application of the native compound. Alkaloid lappaconitine extracted from various Aconitum and Delphinium species has displayed extensive bioactivities and active ongoing research to reduce its adverse effects. A convenient route to construct hybrid molecules containing diterpenoid alkaloid lappaconitine and 3H-1,5-benzodiazepine fragments was proposed. The key stage involved the formation of 5'-alkynone-lappaconitines in situ by acyl Sonogashira coupling of 5'-ethynyllappaconitine, followed by cyclocondensation with o-phenylenediamine. New hybrid compounds showed low toxicity and outstanding analgesic activity in experimental pain models, which depended on the nature of the substituent in the benzodiazepine nucleus. An analogous dependence was also shown for the antiarrhythmic activity in the epinephrine arrhythmia test in vivo. Studies on the isolated atrium have shown that the mechanism of action of the new compounds is included the blockade of beta-adrenergic receptors and potassium channels. Molecular docking analysis was conducted to determine the binding potential of target molecules with the voltage-gated sodium channel NaV1.5. All obtained results provide a basis for future rational modifications of lappaconitine, reducing side effects, while retaining its therapeutic effects.

Neuropharmacological Potential of Diterpenoid Alkaloids

This study provides a narrative review of diterpenoid alkaloids (DAs), a family of extremely important natural products found predominantly in some species of Aconitum and Delphinium (Ranunculaceae). DAs have long been a focus of research attention due to their numerous intricate structures and diverse biological activities, especially in the central nervous system (CNS). These alkaloids originate through the amination reaction of tetra or pentacyclic diterpenoids, which are classified into three categories and 46 types based on the number of carbon atoms in the backbone structure and structural differences. The main chemical characteristics of DAs are their heterocyclic systems containing β-aminoethanol, methylamine, or ethylamine functionality. Although the role of tertiary nitrogen in ring A and the polycyclic complex structure are of great importance in drug-receptor affinity, in silico studies have emphasized the role of certain sidechains in C13, C14, and C8. DAs showed antiepileptic effects in preclinical studies mostly through Na⁺ channels. Aconitine (1) and 3-acetyl aconitine (2) can desensitize Na⁺ channels after persistent activation. Lappaconitine (3), N-deacetyllapaconitine (4), 6-benzoylheteratisine (5), and 1-benzoylnapelline (6) deactivate these channels. Methyllycaconitine (16), mainly found in Delphinium species, possesses an extreme affinity for the binding sites of α7 nicotinic acetylcholine receptors (nAChR) and contributes to a wide range of neurologic functions and the release of neurotransmitters. Several DAs such as bulleyaconitine A (17), (3), and mesaconitine (8) from Aconitum species have a drastic analgesic effect. Among them, compound 17 has been used in China for decades. Their effect is explained by increasing the release of dynorphin A, activating the inhibitory noradrenergic neurons in the β-adrenergic system, and preventing the transmission of pain messages by inactivating the Na⁺ channels that have been stressed. Acetylcholinesterase inhibitory, neuroprotective, antidepressant, and anxiolytic activities are other CNS effects that have been investigated for certain DAs. However, despite various CNS effects, recent advances in developing new drugs from DAs were insignificant due to their neurotoxicity.

A mid-infrared spectroscopy-random forest system for the origin tracing of Chinese geographical indication Aconiti Lateralis Radix Praeparata

Reliable origin certification methods are essential for the protection of high-value genuine medicinal material with designated origins and geographical indication (GI) products. Aconiti Lateralis Radix Praeparata (Fuzi), one well-known traditional Chinese medicine and geographical indication products have remarkable efficacy and wide clinical application, with high demand in domestic and international markets. The efficacy and price of Fuzi from different origins vary, and it is difficult for the general public to accurately identify them through traditional experience. The mass spectrometry detection technology based on the plant metabolomics is tedious and lengthy in test sample preparation, complicated in operation, long in detection time, and low in reproducibility. As a sophisticated, green, fast, and low-loss detection technique, infrared spectroscopy is integrated by machine learning to bring new ways for quality regulation and control of traditional Chinese medicines. An analytical method based on mid-infrared spectroscopy combined with a random forest algorithm was developed to verify the geographical origin of authentic herbs and/or GI products. The method successfully predicted and classified three varieties of Chinese GI Fuzi and four varieties of non-GI Fuzi. In this study, an environment-friendly traceability strategy with fast analysis, low sample loss and high precision was used to provide a new strategy for identifying the origin of Fuzi.

Efficacy analysis and research progress of complementary and alternative medicines in the adjuvant treatment of COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has impacted human lifestyles around the world, causing huge distress in terms of public health systems, emergency response capacity and economic development. The causative agent of COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is associated with respiratory involvement, cardiovascular-related diseases, and ultimately causes multiple organ failure and death in severely affected individuals. Thus, effective prevention or early treatment of COVID-19 is critical. An effective vaccine offers a way out of the pandemic for governments, the scientific community and people worldwide, but we still lack effective drug therapies, including treatments for the prevention and treatment of COVID-19. This had led to a high global demand for many complementary and alternative medicines (CAMs). Moreover, many healthcare providers are now requesting information about CAMs that prevent, relieve, or treat the symptoms of COVID-19 and even alleviate vaccine-related side effects. Experts and scholars must therefore become familiar with the use of CAMs in COVID-19, current research directions and effectiveness of CAMs for COVID-19. This narrative review updates the current status and research worldwide on the use of CAMs for COVID-19. The review provides reliable evidence on theoretical viewpoints and therapeutic efficacies of CAM combinations, and evidence in support of the therapeutic strategy of Taiwan Chingguan Erhau (NRICM102) against moderate-to-severe novel coronavirus infectious disease in Taiwan.

Compositions analysis and insecticidal activity of Aconitum polycarpum Chang ex W.T.Wang petroleum ether fractions and essential oils

ETHNOPHARMACOLOGICAL RELEVANCE

The Aconitum genus plants as a natural pesticide for insecticide and rodent control has been recorded in Chinese folk. However, the insecticide effect, mechanism, and active composition of Aconitum polycarpum Chang ex W.T.Wang have not been studied further.

AIM OF THE STUDY

This study was designed to analyze the chemical composition, evaluate contact toxicity of petroleum ether extracts (PEEs) and essential oils (EOs) of A. polycarpum, and further explore their possible insecticidal mechanism.

MATERIALS AND METHODS

The roots of A. polycarpum were extracted with 90% methanol, and then extracted with petroleum ether to obtain PEEs; the EOs was extracted by distillation. The chemical compositions of PEEs and EOs were analyzed by GC-MS. Contact toxicity was evaluated by the immersion method. Exploring insecticidal mechanisms through in vitro enzyme inhibitory activity.

RESULTS

12 compounds were identified from PEEs by GC-MS, mainly including aliphatic (94.8%), the main compositions were Octadecadienol (ODO) (aliphatic, 53.2%) and L-Ascorbyl dipalmitate (LADP) (aliphatic, 36.1%). 24 compounds were identified in EOs. About 44.6% of the identified components were terpenoids and their derivatives, and the rest were mainly aliphatic (34.7%) and phenols (3.0%). The main chemical components were L (-)-Borneol (LB) (terpenoid, 28.3%), LADP (aliphatic, 19.1%), and Isoborneol (terpenoid, 9.1%). The contact toxicity indicated that the PEEs showed great contact toxicity against Spodoptera exigua (LC₅₀ = 126.2 mg/L). Meanwhile, LADP (LC₅₀ = 128.1 mg/L) and ODO (LC₅₀ = 121.3 mg/L) was similar to that of Cyhalothrin (LC₅₀ = 124.2 mg/L) in contact toxicity. In addition, we found that LADP and ODO exhibited excellent inhibitory activity against CarE (IC₅₀ = 58.0, 56.1 mg/L, respectively) by measuring in vitro enzyme inhibitory activity, which was superior than Cyhalothrin (IC₅₀ = 68.1 mg/L).

CONCLUSIONS

The chemical compositions and contact toxicity of EOs and PEEs of A. polycarpum were analyzed and evaluated, and their insecticidal mechanisms were preliminarily discussed for the first time. It proved PEEs of A. polycarpum and its main components (LADP and ODO) exhibited excellent contact toxicity against S. exigua, and CarE was identified as a potential target for contact toxicity. This study indicated that the insecticidal activity of petroleum ether extracts from A. polycarpum is quite promising, and provides a practical and scientific basis for the development and application of botanical pesticides.

Neoline, fuziline, songorine and 10-OH mesaconitine are potential quality markers of Fuzi: In vitro and in vivo explorations as well as pharmacokinetics, efficacy and toxicity evaluations

ETHNOPHARMACOLOGICAL RELEVANCE

Fuzi, the lateral roots of Aconitum carmichaelii Debx, plays an irreplaceable role in treating Yang deficiency and cold coagulation syndromes. However, Fuzi has a narrow margin of safety since its pharmacological constituents, Aconitum alkaloids, have potential cardiotoxicity and neurotoxicity. The current quality markers (Q-markers) for the control of Fuzi's efficacy and toxicity are 3 monoester-diterpenoid alkaloids, namely, benzoylaconine (BAC), benzoylhypaconine and benzoylmesaconine (BMA) and 3 diester-diterpenoid alkaloids, namely, aconitine (AC), hypaconitine and mesaconitine (MA). However, mounting evidence indicates that the current 6 Q-markers may not be efficacy- or toxicity-specific enough for Fuzi.

AIM OF THE STUDY

The aim of this study was to explore and evaluate efficacy- or toxicity-specific potential quality markers (PQ-markers) of Fuzi.

MATERIALS AND METHODS

PQ-markers were explored by analyzing 30 medicinal samples and alkaloids exposed in mouse. Pharmacokinetics of PQ-markers on C57BL/6J mice were determined. Anti-inflammatory effects of PQ-markers were evaluated by λ-carrageenan-induced paw edema model and lipopolysaccharide-induced RAW264.7 cell inflammatory model, while analgesic effects were assessed by acetic acid-induced pain model and Hargreaves test. Cardiotoxicity and neurotoxicity of PQ-markers were assessed by histological and biochemical analyses, while acute toxicity was evaluated by modified Kirschner method.

RESULTS

After in vitro and in vivo explorations, 7 PQ-markers, namely, neoline (NE), fuziline (FE), songorine (SE), 10-OH mesaconitine (10-OH MA), talatizamine, isotalatizidine and 16β-OH cardiopetalline, were found. In the herbal medicines, NE, FE, SE and 10-OH MA were found in greater abundance than many other alkaloids. Specifically, the amounts of NE, FE and SE in the Fuzi samples were all far higher than that of BAC, and the contents of 10-OH MA in 56.67% of the samples were higher than that of AC. In mouse plasma and tissues, NE, FE, SE, talatizamine, isotalatizidine and 16β-OH cardiopetalline had higher contents than the other alkaloids, including the 6 current Q-markers. The pharmacokinetics, efficacy and toxicity of NE, FE, SE and 10-OH MA were further evaluated. The average oral bioavailabilities of NE (63.82%), FE (18.14%) and SE (49.51%) were higher than that of BMA (3.05%). Additionally, NE, FE and SE produced dose-dependent anti-inflammatory and analgesic effects, and their actions were greater than those of BMA. Concurrently, the toxicities of NE, FE and SE were lower than those of BMA, since no cardiotoxicity or neurotoxicity was found in mice after NE, FE and SE treatment, while BMA treatment notably increased the creatine kinase activity and matrix metalloproteinase 9 level in mice. The average oral bioavailability of 10-OH MA (7.02%) was higher than that of MA (1.88%). The median lethal dose (LD₅₀) of 10-OH MA in mice (0.11 mg/kg) after intravenous injection was close to that of MA (0.13 mg/kg). Moreover, 10-OH MA produced significant cardiotoxicity and neurotoxicity, and notable anti-inflammatory and analgesic effects that were comparable to those of MA.

CONCLUSIONS

Seven PQ-markers of Fuzi were found after in vitro and in vivo explorations. Among them, NE, FE and SE were found to be more efficacy-specific than BMA, and 10-OH MA was as toxicity-specific as MA.

Characterization of a Root-Knot Nematode Infecting Aconitum carmichaelii in Southwest China

Growth of the Chinese herbal medicine industry has resulted in several new pests and diseases. China is one of the world largest producers of monkshood (Aconitum carmichaelii Debx.), but an unidentified root-knot nematode has become a significant pest in the southwestern provinces of Yunnan and Sichuan. Morphological characteristics and the ribosomal DNA-internal transcribed spacer and D2-D3 region of the 28S ribosomal RNA gene sequences were used to identify the nematode as Meloidogyne hapla. Through investigation, this is the first report of M. hapla infecting monkshood in Yunnan and Sichuan Provinces.

Neurotoxicity mechanism of aconitine in HT22 cells studied by microfluidic chip-mass spectrometry

Aconitine, a common and main toxic component of Aconitum, is toxic to the central nervous system. However, the mechanism of aconitine neurotoxicity is not yet clear. In this work, we had the hypothesis that excitatory amino acids can trigger excitotoxicity as a pointcut to explore the mechanism of neurotoxicity induced by aconitine. HT22 cells were simulated by aconitine and the changes of target cell metabolites were real-time online investigated based on a microfluidic chip-mass spectrometry system. Meanwhile, to confirm the metabolic mechanism of aconitine toxicity on HT22 cells, the levels of lactate dehydrogenase, intracellular Ca²⁺, reactive oxygen species, glutathione and superoxide dismutase, and ratio of Bax/Bcl-2 protein were detected by molecular biotechnology. Integration of the detected results revealed that neurotoxicity induced by aconitine was associated with the process of excitotoxicity caused by glutamic acid and aspartic acid, which was followed by the accumulation of lactic acid and reduction of glucose. The surge of extracellular glutamic acid could further lead to a series of cascade reactions including intracellular Ca²⁺ overload and oxidative stress, and eventually result in cell apoptosis. In general, we illustrated a new mechanism of aconitine neurotoxicity and presented a novel analysis strategy that real-time online monitoring of cell metabolites can provide a new approach to mechanism analysis.

Unprecedented diterpene skeletons isolated from vascular plants in the last twenty years (2001-2021)

Every year there are hundreds of reports about the isolation of undescribed terpenoids based on novel functionalizations of known carbocyclic skeletons series. However, on some occasions the compounds obtained have a carbocyclic skeleton that does not correspond with the series established, in these peculiar opportunities, in addition to finding an undescribed natural product, is obtained an unprecedented carbocyclic skeleton, whose biogenesis must necessarily involve other additional steps that explain its formation. This review accounts for the reports of seventy-nine unprecedented diterpene skeletons (corresponding to one-hundred-three undescribed diterpenoids) isolated from vascular plants in the last two decades. According to the genus, Euphorbia and Salvia are the most prolific in reports of unprecedented diterpene skeletons with a total of twenty, and nine skeletons, respectively. If the findings are expressed in terms of the family, Euphorbiaceae and Lamiaceae have the highest number of reports of undescribed diterpene skeletons, with twenty-seven and twenty-two, respectively. Finally, fifty-three skeletons are derived from higher diterpenoids (2-12, 68, 69, 86, 104-109, 158-161, 186, 189, 222, 250-255, 285-298, 403-404, 415, 416, and 436), twenty are derived from lower diterpenoids (135, 136, 192-194, 225-229, 363-370, 397, and 425), and six (96, 97, 147, 148, 205, and 206) are derived from skeletons whose biogenesis has not yet been established, or at least, cannot be formally included within the groups mentioned above. This article comprehensively highlights the hypothetical biosynthetic pathway for each of the one-hundred-three undescribed compounds with unprecedented diterpene skeletons and summarizes their most significant biological activities.

Plant and fungi derived analgesic natural products targeting voltage-gated sodium and calcium channels

Voltage-gated sodium and calcium channels (VGSCs and VGCCs) play an important role in the modulation of physiologically relevant processes in excitable cells that range from action potential generation to neurotransmission. Once their expression and/or function is altered in disease, specific pharmacological approaches become necessary to mitigate the negative consequences of such dysregulation. Several classes of small molecules have been developed with demonstrated effectiveness on VGSCs and VGCCs; however, off-target effects have also been described, limiting their use and spurring efforts to find more specific and safer molecules to target these channels. There are a great number of plants and herbal preparations that have been empirically used for the treatment of diseases in which VGSCs and VGCCs are involved. Some of these natural products have progressed to clinical trials, while others are under investigation for their action mechanisms on signaling pathways, including channels. In this review, we synthesize information from ~30 compounds derived from natural sources like plants and fungi and delineate their effects on VGSCs and VGCCs in human disease, particularly pain. [Figure: see text].

Aconitum coreanum Rapaics: Botany, traditional uses, phytochemistry, pharmacology, and toxicology

The present review summarizes the multifaceted uses and recent findings regarding the phytochemistry, traditional use, pharmacology, and toxicity of the extracts and compounds of Aconitum coreanum Rapaics (Ranunculaceae) for the first time to facilitate further research and exploitation of these types of compounds and the utilization of A. coreanum plants. A. coreanum is one of the most important medicinal Aconitum species and has been traditionally and popularly used in China and other Asian countries for the treatment of headaches and migraines, Bi syndrome induced by wind, cold and dampness, and facial paralysis. Phytochemical studies have led to the isolation of 55 distinct small molecule compounds from A. coreanum, most of which are diterpenoid alkaloids. Related pharmacological studies have focused primarily on the antiarrhythmic, anti-inflammatory, analgesic, and anticancer activities of A. coreanum and its derived drugs. Alkaloids have been demonstrated to be the main active ingredients in this plant. In particular, hetisine-type DAs, mainly Guan-fu base A and its analogues, which possess prominent antiarrhythmic effects, other effects, and hypotoxicity, could be regarded as the representative constituents of A. coreanum. Polysaccharides from A. coreanum also displayed broad bioactivities, demonstrating great potential for further research and exploitation. However, few of the current studies have examined the main active components in A. coreanum from different regions. In addition, most of the pharmacological studies on A. coreanum polysaccharides were carried out using crude or poorly characterized fractions. Finally, reliable analytical methods and deeper studies on the toxicity of the compounds from A. coreanum are needed to ensure the safe usage of these products.

Processed lateral root of Aconitum carmichaelii Debx.: A review of cardiotonic effects and cardiotoxicity on molecular mechanisms

Fuzi, the lateral root of A. carmichaelii Debx., is a typical traditional herbal medicine with both poisonousness and effectiveness, and often used in the treatment of heart failure and other heart diseases. In this review, we searched domestic and foreign literature to sort out the molecular mechanisms of cardiotonic and cardiotoxicity of Fuzi, also including its components. The major bioactive components of Fuzi for cardiotonic are total alkaloids, polysaccharide and the water-soluble alkaloids, with specific mechanisms manifested in the inhibition of myocardial fibrosis, apoptosis and autophagy, and improvement of mitochondrial energy metabolism, which involves RAAS system, PI3K/AKT, JAK/STAT, AMPK/mTOR signaling pathway, etc. Diester-diterpenoid alkaloids in Fuzi can produce cardiotoxic effects by over-activating Na⁺ and Ca²⁺ ion channels, over-activating NLRP3/ASC/caspase-3 inflammatory pathway and mitochondria mediated apoptosis pathway. And three clinically used preparations containing Fuzi are also used as representatives to summarize their cardiac-strengthening molecular mechanisms. To sum up, Fuzi has shown valuable cardiotonic effects due to extensive basic and clinical studies, but its cardiotonic mechanisms have not been systematically sorted out. Therefore, it is a need for deeper investigation in the mechanisms of water-soluble alkaloids with low content but obvious therapeutic effect, as well as polysaccharide.

Identification and quantification of eight alkaloids in Aconitum heterophyllum using UHPLC-DAD-QTOF-IMS: A valuable tool for quality control

INTRODUCTION

Aconitum spp. are prime medicinal plants rich in alkaloids and have been used as the main constituents of traditional medicine in India and China. The whole plant can be toxic and creates pathophysiological conditions inside the human body. Therefore, simultaneous quantification of alkaloids within plant parts and herbal medicines associated with this genus is essential for quality control.

OBJECTIVE

We aimed to develop and validate methods using ultra-high-performance liquid chromatography-diode array detector-quadrupole time-of-flight ion mobility mass spectrometry (UHPLC-DAD-QTOF-IMS) and to develop an analytical strategy for the identification and quantification of alkaloid compounds (aconitine, hypaconitine, mesaconitine, aconine, benzoylmesaconitine, benzoylaconine, bulleyaconitine A, and deoxyaconitine) from Aconitum heterophyllum.

METHODOLOGY

We developed a simultaneous identification and quantification method for eight alkaloids using UHPLC-DAD-QTOF-IMS. The method was validated as per International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines and also in IMS mode.

RESULTS

The developed method has good linearity (r²  = 0.997-0.999), LOD (0.63-8.31 μg/mL), LOQ (0.63-2.80 μg/mL), recovery (86.01-104.33%), reproducibility, intra- and inter-day variability (<3.25%), and stability. Significant qualitative and quantitative variations were found among different plant parts (flower, leaf, stem, root, and tuber) and five market products of A. heterophyllum. Furthermore, a total of 21 metabolites were also profiled based on the fragmentation pattern of MS² using the validated method.

CONCLUSION

An appropriate mobile phase using acetonitrile and water in a gradient elution gave a satisfactory chromatographic separation of eight Aconitum alkaloids with their adjacent peaks. Therefore, this method could provide a scientific and technical platform for quality control assurance.

The effect of compatibility of Aconiti Radix and honey on the pharmacokinetics of five Aconitum alkaloids in rat plasma

Aconiti Radix (Chuanwu [CW]), is widely used for the treatment of the chronic and intractable diseases due to its remarkable curative effect. CW has been combined with honey for thousands of years to reduce toxicity and enhance efficacy. This study first clarified compatibility mechanism of CW co-used with honey using a comparative pharmacokinetic idea. We developed and validated a simple, sensitive, specific, and accurate UHPLC-MS/MS method to simultaneously determine five Aconitum alkaloids in rat plasma after oral administration of CW decoction and CW-honey concentrated solution. Pharmacokinetic parameters were significantly different between the two groups (P<0.01 and P<0.05). Compared with CW group, C_max and AUC_0→t were decreased in CW-honey group for three diester-diterpenoid alkaloids (hypaconitine, mesaconitine and aconitine); T_max and T_1/2 were prolonged. However, C_max and AUC_0→t were increased in CW-honey group for two monoester-diterpenoid alkaloids (benzoylaconine and benzoylmesaconine); T_max was shortened; T_1/2 was prolonged. These findings suggest that honey affected the pharmacokinetic behaviors of five Aconitum alkaloids. We speculate that the detoxification and synergism of honey might result from reducing the toxicity of diester-diterpenoid alkaloids and promoting the biological activity of monoester-diterpenoid alkaloids in vivo. This study provides a theoretical basis for the clinical use of CW combined with honey.

Changing Climatic Scenarios Anticipate Dwindling of Suitable Habitats for Endemic Species of Himalaya—Predictions of Ensemble Modelling Using Aconitum heterophyllum as a Model Plant

In the changing climatic conditions, species distribution modelling is considered as a key strategy to estimate the probable influence of climatic variabilities on the habitat ranges of any species. The present study explores the potential distribution of Aconitum heterophyllum under current and future climatic scenarios. The results unfold that the distribution of this endemic species is governed significantly by bio12, i.e., Annual Precipitation. Ensemble modelling predicted that higher altitudes of Jammu, Kashmir and Ladakh are suitable habitats for A. heterophyllum. However, the future climatic modelling revealed that there will be a significant decrease in the suitable habitats for A. heterophyllum. Most of the shrinkage of habitats is predicted to occur within the time period of 2050, which seriously challenges their survival. The present study recommends an urgent need to frame a pertinent conservation and management policy for Aconitum heterophyllum and will act as a framework for planning such a policy.

Aconitum pendulum and Aconitum flavum: A narrative review on traditional uses, phytochemistry, bioactivities and processing methods

ETHNOPHARMACOLOGICAL RELEVANCE

Composed of dried Aconitum pendulum and Aconitum flavum roots, Tiebangchui, is an important Tibetan medicine and has been traditionally and widely used as a remedy for cold and pain for thousands of years because of its extraordinary pharmacological activities. The toxicity and efficacy of Tiebangchui as a typical toxic traditional Tibetan medicine, are interdependent, and thus to make sure its safe use in clinics is also noteworthy.

AIM OF THE STUDY

This review aims to document and summarize critical and comprehensive information about traditional uses, phytochemistry, pharmacology, toxicology and processing methods of Tiebangchui. Perspectives for possible future investigations have been discussed.

MATERIALS AND METHODS

Relevant information about Tiebangchui (A. pendulum and A. flavum) was collected from internationally recognized electronic scientific databases, such as Web of Science, PubMed, Science Direct, Springer Link, ACS, and CNKI. Then, classic Tibetan medical books, such as Four Medical Tantra, and Jing Zhu Materia Medica, and official drug standards were reviewed.

RESULTS

A total of 95 chemical constituents have been isolated and identified from Tiebangchui, and most of them were diterpenoid alkaloids. These phytochemicals showed a wide range of pharmacological properties, such as anti-inflammation, anti-rheumatoid arthritis, analgesic, local anesthetic, anti-cancer and anti-bacterial activities. Hence, Tiebangchui is broadly used in hundreds of preparations to treat fever, arthritis, rheumatic arthralgia, traumatic injury, furuncle and swelling. Cardiotoxicity, neurotoxicity and gastrointestinal toxicity are the main toxic effects caused by the Aconitum alkaloids of Tiebangchui. Various processing methods, including steaming, decocting and sand-frying, and traditional Tibetan medicine processing methods, such as processing with Hezi decoction, Qingke wine and Zanba, are effective in attenuating toxicity while retaining efficacy.

CONCLUSIONS

The present review provides primary information of Tiebangchui, particularly for its traditional uses, botanical characteristics, phytochemicals, outstanding bioactivities and processing methods. However, studies that explored the in vivo pharmacokinetics and mechanism of Tiebangchui, as well as its quality markers, qualitative and quantitative analysis are still insufficient. Processing methods that attenuate toxicities, evaluations of efficacy, in vivo processes and biological effects, the mechanisms of processed products should be further explored.

Aconitum carmichaelii Debeaux: A systematic review on traditional use, and the chemical structures and pharmacological properties of polysaccharides and phenolic compounds in the roots

ETHNOPHARMACOLOGICAL RELEVANCE

Aconitum carmichaelii, belonging to the Ranunculaceae family, is a widely used traditional herbal plant in Asian countries, especially in China. The lateral ("Fuzi") and mother ("Chuanwu") roots are the two main plant parts used in Traditional Chinese Medicine (TCM), where they are used in the treatment of acute myocardial infarction, heart failure, rheumatoid arthritis, and as analgesics.

AIM OF THE STUDY

In order to further guide the research direction and application of A. carmichaelii, this study aims to give a systematic and in-depth overview on the phytochemical and pharmacological studies of non-alkaloid natural products with focus on polysaccharides and phenolic compounds.

MATERIALS AND METHODS

A comprehensive search in the literature was conducted based on the databases Google Scholar, SciFinder (American Chemical Society), Springer Link, PubMed Science, Science Direct and China National Knowledge Internet, Wanfang Data, in addition to books, doctoral and master's dissertations, and official website. The main keywords were: "Aconitum carmichaelii", "Aconiti Lateralis Radix Praeparata", "Fuzi", "Chuanwu", "Aconiti Radix", "monkshood" and "Bushi".

RESULTS

A. carmichaelii is known for the use of its different root parts, including "Fuzi" and "Chuanwu". Different types of polysaccharides, both neutral and acidic, and 39 phenolic compounds like flavonoids, phenylpropanoids, lignans, neolignans, and benzoic acid derivatives have been isolated and identified from the roots. Pharmacological studies of the isolated polysaccharides have demonstrated various biological effects such as hypoglycemic, hypolipidemic, cardiovascular, immunomodulatory, anti-tumor, and neuropharmacological activities. Studies on pharmacological effects of the phenolic compounds isolated from the roots are however limited.

CONCLUSIONS

This review shows that polysaccharides could be one of the active components in the roots of A. carmichaelii, and they are promising for future applications due to their pharmacological properties. In addition, polysaccharides are generally non-toxic, biocompatible, and biodegradable. This review also sheds light on new research directions for A. carmichaelii. A more detailed structural characterization of polysaccharides from different root parts of A. carmichaelii, and their structure-activity relationships are required. Additionally, their pharmacological properties as immunomodulators in the intestinal system should be investigated. Further, more knowledge about the pharmacological effects and molecular mechanisms of the phenolic compounds that have been identified are needed.

Identification and poisoning diagnosis of Aconitum materials using a genus-specific nucleotide signature

Aconitum genus generally contains hypertoxic alkaloids. Poisoning incidents due to the improper ingestion of Aconitum materials frequently occur around the world. DNA barcoding is considered as a powerful tool for species identification, but complete sequences of conventional DNA barcodes are sometimes unattainable from food and highly processed products due to severe DNA degradation. Therefore, a shorter molecular marker will be more profitable for the authentication and poisoning diagnosis of Aconitum materials. In this study, 1246 psbA-trnH sequences and chloroplast genomes representing 183 taxa of Aconitum were collected, and a 23-bp nucleotide signature unique to Aconitum genus (5'-TATATGAGTCATTGAAGTTGCAG-3') was developed. The nucleotide signature was conserved and universal within Aconitum while divergent among other genera. The specific molecular signature was then successfully applied to the detection of processed Aconitum ingredients. To further evaluate the application potential of nucleotide signature in completely unknown mixture samples, boiled food mixtures, containing different ratios of Aconitum materials, were sequenced by high-throughput sequencing technology. The results showed that the nucleotide signature sequence could be directly extracted from raw sequencing data, even at a low DNA concentration of 0.2 ng/µl. Consequently, the 23-bp genus-specific nucleotide signature represents a significant step forward in the use of DNA barcoding to identify processed samples and food mixtures with degraded DNA. This study undoubtedly provides a new perspective and strong support for the identification and detection of Aconitum-containing products, which can be further introduced to the diagnosis of food poisoning.

Analgesic Alkaloids Derived From Traditional Chinese Medicine in Pain Management

Chronic pain is one of the most prevalent health problems. The establishment of chronic pain is complex. Current medication for chronic pain mainly dependent on anticonvulsants, tricyclic antidepressants and opioidergic drugs. However, they have limited therapeutic efficacy, and some even with severe side effects. We turned our interest into alkaloids separated from traditional Chinese medicine (TCM), that usually act on multiple drug targets. In this article, we introduced the best-studied analgesic alkaloids derived from TCM, including tetrahydropalmatine, aloperine, oxysophocarpine, matrine, sinomenine, ligustrazine, evodiamine, brucine, tetrandrine, Stopholidine, and lappaconitine, focusing on their mechanisms and potential clinical applications. To better describe the mechanism of these alkaloids, we adopted the concept of drug-cloud (dCloud) theory. dCloud illustrated the full therapeutic spectrum of multitarget analgesics with two dimensions, which are “direct efficacy”, including inhibition of ion channels, activating γ-Aminobutyric Acid/opioid receptors, to suppress pain signal directly; and “background efficacy”, including reducing neuronal inflammation/oxidative stress, inhibition of glial cell activation, restoring the balance between excitatory and inhibitory neurotransmission, to cure the root causes of chronic pain. Empirical evidence showed drug combination is beneficial to 30–50% chronic pain patients. To promote the discovery of effective analgesic combinations, we introduced an ancient Chinese therapeutic regimen that combines herbal drugs with “Jun”, “Chen”, “Zuo”, and “Shi” properties. In dCloud, “Jun” drug acts directly on the major symptom of the disease; “Chen” drug generates major background effects; “Zuo” drug has salutary and supportive functions; and “Shi” drug facilitates drug delivery to the targeted tissue. Subsequently, using this concept, we interpreted the therapeutic effect of established analgesic compositions containing TCM derived analgesic alkaloids, which may contribute to the establishment of an alternative drug discovery model.

Management of a patient with polymorphic ventricular tachycardia from aconitum poisoning

An 81-year-old man presented to the Emergency Department with shortness of breath, generalised weakness, numbness, giddiness, nausea and vomiting after consuming an inadequately prepared Traditional Chinese Medicine preparation that contained herbal aconitum (Chuanwu and Caowu). His electrocardiogram (ECG) and rhythm strips showed multiple runs of non-sustained ventricular tachycardia monomorphic ventricular tachycardia and slowed polymorphic ventricular tachycardia. He was treated with intravenous (IV) amiodarone, magnesium and lignocaine, and was started on IV noradrenaline after developing haemodynamic compromise. There was no digoxin detected in the blood and urine. At 12 h, aconitine was not detected in the blood (cut off at <1 ng/mL) but aconitine and hypaconitine was detected in the urine qualitatively. He underwent a coronary angiogram at 12 h post-admission which showed minor coronary artery disease. A formal echocardiogram showed left ventricular ejection fraction 50–55% with no regional wall motion abnormalities of the left ventricle. He made an uneventful recovery and reverted to normal sinus rhythm at 29 h of admission. He was discharged well on Day 4 of admission with a diagnosis of polymorphic ventricular tachycardia secondary to Aconitum poisoning.

Anti-rheumatic, and analgesic effects by the parent tuberous roots of Aconitum jaluense in adjuvant induced arthritis rats

AIM OF THE STUDY

The aim of this study was to test the anti-rheumatic effects of A. jaluense tubers in acute and chronic arthritis rats, and to assign its ingredients through UHPLC-TOF/MS.

MATERIALS AND METHODS

Subcutaneous injection of carrageenan for acute arthritis and complete Freund's adjuvant (CFA) for chronic arthritis was carried out in the hind paw of SD rats. The paw volume was measured by a plethysmometer thermal hyperalgesia was tested using a thermal plantar tester, and mechanical hyperalgesia was evaluated by ankle flexion evoked vocalizations. The expression of c-Fos in the brain hippocampus was measured with the avidin-biotin-peroxidase technique. The ingredients were assigned by UHPLC-TOF/MS, chromatography was performed by UHPLC system with DAD detector and BEH C₁₈ column, and spectroscopy was conducted by ESI-MS system.

RESULTS AND DISCUSSION

The 80% ethanoic extract of A. jaluense tubers showed an acute anti-inflammatory effect by suppressing the edema volume in the hind paw of carrageenan-stimulated rats. In addition, A. jaluense tubers exerted an anti-rheumatic activity by reducing the secondary swelling volume from an immunological reaction in the left hind paw of CFA-induced chronic arthritis rats. Additionally, oral treatment with the 80% ethanoic extract -showed potent analgesic effects in the arthritis rats by recovering the paw withdrawal latency stimulated by the thermal hyperalgesia and by reducing the vocalization scores evoked by ankle flexion on both hind paws. Moreover, its treatment also indicated an anti-psychiatric effect by controlling the c-Fos protein expression of the brain hippocampus in CFA-stimulated arthritis rats. These results suggested that these therapeutic effects were exhibited by less toxic mono-esterified diterpenoid alkaloids (MDAs), and nontoxic non-esterified diterpenoid alkaloids (NDAs).

CONCLUSION

A. jaluense tubers may act as viable therapeutic or preventive candidates for acute and chronic arthritis, particularly, for immune-inflammatory rheumatoid arthritis to suppress the pain and psychiatric condition.

The effectiveness of Fuzi in combination with routine heart failure treatment on chronic heart failure patients

ETHNOPHARMACOLOGICAL RELEVANCE

Fuzi, Aconiti Lateralis Radix Praeparata, is widely used in Traditional Chinese Medicine (TCM) for the treatment of acute heart failure (HF) for 2000 years. However, the clinical evidence of Fuzi in the treatment of chronic HF is limited, especially when used in combination with Western medications.

MATERIALS AND METHODS

This population-based propensity score (PS)-matched cohort study aimed to evaluate the effectiveness of Fuzi on the chronic HF. From 4753 chronic HF patients who had used TCM herbal medicine, we performed 1:1 PS matching and selected target patients with (n = 921) and without (n = 921) Fuzi use for further analysis. The primary outcomes were all-cause mortality and composite cardiovascular (CV) outcomes. Hazard ratio (HR) was calculated by Cox proportional hazard regression and the competing risk analysis. The dose-response relationship and the association between the initiation of TCM herbal medicine and the primary outcomes were evaluated by restricted cubic spline (RCS) functions.

RESULTS

There was no difference in all-cause mortality (HR, 0.99; 95% confidence interval [CI], 0.76-1.27) and composite CV outcomes (HR, 0.96; 95% CI, 0.84-1.11) between the Fuzi user and non-user groups. For CV safety issue, the result showed that Fuzi use was not associated with a higher risk of cardiac arrhythmias (HR, 1.03; 95% CI, 0.83-1.29). The dose-response relationship showed that Fuzi cumulative dose (≥150g) was associated with lower composite CV risk (HR, 0.76; 95% CI, 0.59-0.99). In addition, the RCS model showed that late initiation (≥2.5 years) of TCM herbal drugs in chronic HF patients had a higher risk of all-cause mortality (HR, 1.81; 95%CI, 1.07-3.08).

CONCLUSIONS

This study is the first real-world evidence to demonstrate the effect of Fuzi combined with routine HF treatment. Importantly, the result indicated that long-term Fuzi use had a significant benefit in preventing cardiovascular events. The late initiation of TCM herbal drugs was associated with a higher risk of all-cause mortality. Further clinical trials are needed to support or undermine the assumption of using Fuzi and current Western medications to treat chronic HF.

Hematological and Histopathological Effects of Subacute Aconitine Poisoning in Mouse

Aconitine is the principal toxic ingredient of Aconitum, which can cause systemic poisoning involving multiple organs and systems after animal ingestion. The purpose of this study was to investigate the effects of aconitine on hematological indices and histological changes in mice. One hundred twenty mice were divided into a control group (normal saline), low-dose group (0.14 μmol/L), middle-dose group (0.28 μmol/L) and high-dose group (0.56 μmol/L), which were continuously lavaged for 30 days. The blood of 10 mice were collected randomly and analyzed by group at the 10th, 20th, and 30th days, and some tissues were collected and stained with hematoxylin-eosin to observe histological changes at the 30th day. Compared with the control group, the organ coefficient (%) of liver, spleen, lungs, and brain of the high-dose group were significantly increased (p < 0.05 or p < 0.01). WBC and Gran initially decreased and then increased in each poisoning group, with significant differences in the high-dose group (p < 0.05 or p < 0.01). RBC, HGB, HCT, and PLT decreased continuously in all groups except the low-dose group at the 20th and 30th days (p < 0.05 or p < 0.01). Moreover, BUN, ALT and AST increased in each poisoning group, in comparison with the control group, with significant differences except for the low-dose group (p < 0.05 or p < 0.01). CRE initially increased and then decreased, the TP and ALB decreased, with significant differences observed in the high-dose and middle-dose groups (p < 0.05). All the mice in the poison-treated groups showed varying degrees of histopathological changes such as degeneration and necrosis of tissues, especially heart and cerebellum. Our data suggest that different doses of aconitine have remarkable effects on hematological and histopathological changes in mice, in a significant time and dose-effect relationship.

Establishment of a High Content Image Platform to Measure NF-κB Nuclear Translocation in LPS-Induced RAW264.7 Macrophages for Screening Anti-inflammatory Drug Candidates

BACKGROUND

High content image (HCI), an automatic imaging and analysis system, provides a fast drug screening method by detecting the subcellular distribution of protein in intact cells.

OBJECTIVE

This study established the first standardized HCI platform for lipopolysaccharide (LPS)-induced RAW264.7 macrophages to screen anti-inflammatory compounds by measuring nuclear factor-κB (NF-κB) nuclear translocation.

METHOD

The influence of the cell passages, cell density, LPS induction time and concentration, antibody dilution, serum, dimethyl sulfoxide and analysis parameters on NF-κB nuclear translocation and HCI data quality was optimized. The BAY-11-7085, the positive control for inhibiting NF-κB and Western blot assay were separately employed to verify the stability and reliability of the platform. Lastly, the effect of BHA on NO release, iNOS expression, IL-1β, IL-6, and TNF-α mRNA in LPS-induced RAW264.7 cells was detected.

RESULTS

The optimal conditions for measuring NF-κB translocation in LPS-induced RAW264.7 cells by HCI were established. Cells that do not exceed 22 passages were seeded at a density of 10 k cells/well and pretreated with compounds following 200 ng/mL LPS for 40 min. Parameters including nuclear area of 65 μm2, cell area of 80 μm2, collar of 0.9 μm and sensitivity of 25% were recommended for image segmentation algorithms in the analysis workstation. Benzoylhypaconine from aconite was screened for the first time as an anti-inflammatory candidate by the established HCI platform. The inhibitory effect of benzoylhypaconine on NF-κB translocation was verified by Western blot. Furthermore, benzoylhypaconine reduced the release of NO, inhibited the expression of iNOS, decreased the mRNA levels of IL-1β, IL-6, and TNF-α.

CONCLUSION

The established HCI platform could be applied to screen anti-inflammatory compounds by measuring the NF-κB nuclear translocation in LPS-induced RAW264.7 cells.

The diterpenoid alkaloids

The diterpenoid alkaloids are a family of extremely important natural products that have long been a research hotspot due to their myriad of intricate structures and diverse biological properties. This chapter systematically summarizes the past 11 years (2009-2019) of studies on the diterpenoid alkaloids, including the "so-called" atypical ones, covering the classification and biogenetic relationships, phytochemistry together with 444 new alkaloids covering 32 novel skeletons and the corrected structures, chemical reactions including conversion toward toxoids, synthetic studies, as well as biological activities. It should be noted that the synthetic studies, especially the total syntheses of various diterpenoid alkaloids, are for the first time reviewed in this treatise. This chapter, in combination with our four previous reviews in volumes 42, 59, 67, and 69, will present to the readers a more completed and updated profile of the diterpenoid alkaloids.

Attenuated Structural Transformation of Indaconitine during Sand Frying Process and Anti-Arrhythmic Effects of Its Transformed Products

The transformation pathways of diterpenoid alkaloids have been clarified clearly in the boiling and steaming process, but remain to be determined in the sand frying process. The aims of the study were to investigate the transformation pathways of indaconitine in the sand frying process, as well as examine the cardiotoxicity and anti-arrhythmic activity of indaconitine and its transformed products. The transformed product was separated by column chromatography, and the structure was identified by ¹H NMR, ¹³C NMR, and HR-ESI-MS. The cardiotoxicity of indaconitine and its transformed products was clarified by observing the electrocardiogram (ECG) changes at the same dose. Furthermore, the anti-arrhythmic activity of the transformed products was investigated using an aconitine-induced rat arrhythmia model. Consequently, Δ¹⁵⁽¹⁶⁾-16-demethoxyindaconitine, a new diterpenoid alkaloid, was isolated from processed indaconitine. Intravenous injection of 0.06 mg/kg indaconitine induced arrhythmias in SD rats, while Δ¹⁵⁽¹⁶⁾-16-demethoxyindaconitine did not exhibit arrhythmias at the same dose. In the anti-arrhythmic assay, mithaconitine, obtained in the previous research, together with Δ¹⁵⁽¹⁶⁾-16-demethoxyindaconitine, could dose-dependently delay the onset time of ventricular premature beat (VPB) and reduce the incidence of ventricular tachycardia (VT), combined with the increasing arrhythmia inhibition rate, exhibiting strong anti-arrhythmic activities. These results indicated that two or more pathways exist in the sand frying process, and the transformed products exhibited lower cardiotoxicity and strong anti-arrhythmic activities, which had the possibility of being developed into anti-arrhythmic drugs.

Aconitine induces autophagy via activating oxidative DNA damage-mediated AMPK/ULK1 signaling pathway in H9c2 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Aconitum species, with a medicinal history of 2000 years, was traditionally used in the treatment of rheumatism, arthritis, bruises, and pains. However, many studies have reported that Aconitum species can cause arrhythmia in experimental animals, resulting in myocardial fibrosis and cardiomyocyte damage. Cardiotoxicity is the main toxic effect of aconitine, but the detailed mechanism remains unclear.

AIM OF THE STUDY

This study aimed to explore the effects and underlying mechanism of autophagy in H9c2 cardiomyocytes induced by aconitine.

MATERIALS AND METHODS

H9c2 cells were incubated with different concentrations of aconitine for 24 h, and the intervention sections were pretreated with various inhibitors for 1 h. The effects of aconitine on the oxidative DNA damage, autophagy and viability of H9c2 cells were evaluated by flow cytometry, confocal microscopy, enzyme-linked immunosorbent assay and Western blot.

RESULTS

In H9c2 cells, the cell viability declined, LDH release rate, the number of autophagosomes, protein expression levels of LC3 and Beclin-1 increased significantly after 24 h of aconitine incubation. The pretreatment of autophagy inhibitor 3-MA decreased markedly autophagosomes and protein expression levels of LC3 and Beclin-1, which suggested that aconitine could induce cell autophagy. The significant increase of ROS and 8-OHdG showed that aconitine could cause oxidative DNA damage through ROS accumulation. Meanwhile, treatment of aconitine dramatically increased AMPK^Thr172 and ULK1^Ser317 phosphorylation, and Compound C inhibited AMPK^Thr172 and ULK1^Ser317 phosphorylation, which proved that aconitine induced autophagy via AMPK activation mediated ULK1 phosphorylation. Antioxidant NAC significantly reduced LDH, ROS and 8-OHdG, inhibited the phosphorylation of AMPK^Thr172 and ULK1^Ser317, and down-regulated autophagosomes and proteins expression levels of LC3 and Beclin-1. Consequently, the inhibition of oxidative DNA damage and AMPK/ULK1 signaling pathway alleviated the aconitine-induced autophagic death of H9c2 cells.

CONCLUSIONS

These results showed that aconitine induces autophagy of H9c2 cardiomyocytes by activating AMPK/ULK1 signaling pathway mediated by oxidative DNA damage. The autophagy induced by aconitine in cardiomyocytes is dependent on the activation of the AMPK pathway, which may provide novel insights into the prevention of aconitine-related toxicity.

Regulation of reactive oxygen species by phytochemicals for the management of cancer and diabetes

Cancer and diabetes mellitus are served as typical life-threatening diseases with common risk factors. Developing therapeutic measures in cancers and diabetes have aroused attention for a long time. However, the problems with conventional treatments are in challenge, including side effects, economic burdens, and patient compliance. It is essential to secure safe and efficient therapeutic methods to overcome these issues. As an alternative method, antioxidant and pro-oxidant properties of phytochemicals from edible plants have come to the fore. Phytochemicals are naturally occurring compounds, considered promising agent applicable in treatment of various diseases with beneficial effects. Either antioxidative or pro-oxidative activity of various phytochemicals were found to contribute to regulation of cell proliferation, differentiation, cell cycle arrest, and apoptosis, which can exert preventive and therapeutic effects against cancer and diabetes. In this article, the antioxidant or pro-oxidant effects and underlying mechanisms of flavonoids, alkaloids, and saponins in cancer or diabetic models demonstrated by the recent studies are summarized.

C18-diterpenoid alkaloids in tribe Delphineae (Ranunculaceae): phytochemistry, chemotaxonomy, and bioactivities

This review systematically summarizes the C₁₈-diterpenoid alkaloid (DA) compositions isolated from the genera Aconitum and Delphinium in the Delphineae tribe (Ranunculaceae). A total of 117 distinct C₁₈-DA components have been reported, including 58 lappaconitine-type DAs, 54 ranaconitine-type DAs, and five rearranged-type DAs. These components mainly originated from plants from the subgenus Lycoctonum in the genus Aconitum or less frequently from plants within the genus Delphinium. Natural C₁₈-DAs have exhibited a wide range of bioactivities, including analgesic, antiarrhythmic, anti-inflammatory, anti-tumor, and insecticidal activities, which are closely related to their chemical structures. The high chemical and biological diversities among the reported C₁₈-DA constituents in Delphineae plants indicated their potential as a vast resource for drug discovery. Additionally, the Delphineae plant C₁₈-DAs exhibited chemotaxonomic values and showed a high regularity of distribution at different taxonomic levels; therefore, the Delphineae plant C₁₈-DAs can serve as good chemical molecular markers in the taxonomic treatment of plants within this tribe, especially in the infrageneric division.

This review systematically summarizes the C₁₈-diterpenoid alkaloid (DA) compositions isolated from the genera Aconitum and Delphinium in the Delphineae tribe (Ranunculaceae).

Revealing the efficacy-toxicity relationship of Fuzi in treating rheumatoid arthritis by systems pharmacology

In recent decades, herbal medicines have played more and more important roles in the healthcare system in the world because of the good efficacy. However, with the increasing use of herbal medicines, the toxicity induced by herbal medicines has become a global issue. Therefore, it is needed to investigate the mechanism behind the efficacy and toxicity of herbal medicines. In this study, using Aconiti Lateralis Radix Praeparata (Fuzi) as an example, we adopted a systems pharmacology approach to investigate the mechanism of Fuzi in treating rheumatoid arthritis and in inducing cardiac toxicity and neurotoxicity. The results showed that Fuzi has 25 bioactive compounds that act holistically on 61 targets and 27 pathways to treat rheumatoid arthritis, and modulation of inflammation state is one of the main mechanisms of Fuzi. In addition, the toxicity of Fuzi is linked to 32 compounds that act on 187 targets and 4 pathways, and the targets and pathways can directly modulate the flow of Na+, Ca2+, and K+. We also found out that non-toxic compounds such as myristic acid can act on targets of toxic compounds and therefore may influence the toxicity. The results not only reveal the efficacy and toxicity mechanism of Fuzi, but also add new concept for understanding the toxicity of herbal medicines, i.e., the compounds that are not directly toxic may influence the toxicity as well.

Attenuated Structural Transformation of Aconitine during Sand Frying Process and Antiarrhythmic Effect of Its Converted Products

The transformation pathways of diterpenoid alkaloids have been clarified in the boiling and steaming process. Aconitine, a famous diterpenoid alkaloid, is successively transformed into benzoylaconine and aconine during the processes of boiling and steaming, but the transformation pathway remains to be determined in the sand frying process. The present study aims at investigating the transformation pathways of aconitine in the process of sand frying, as well as assessing the cardiotoxicity and antiarrhythmic activity of aconitine and its converted products. The parameters of temperature and time for the structural transformation of aconitine were confirmed by HPLC. The converted products were further separated and identified by column chromatography, NMR, and HR-ESI-MS. Furthermore, by observing the lead II electrocardiogram (ECG) changes in rats under an equivalent dose, the cardiotoxicity of aconitine and its converted products were compared. Ultimately, the antiarrhythmic effect of the converted products was investigated by employing the model of aconitine-induced arrhythmia. Consequently, the structure of aconitine was converted when processed at 120°C–200°C for 1–40 min. Two diterpenoid alkaloids, a pair of epimers, namely, pyroaconitine and 16-epi-pyroaconitine, were further isolated from processed aconitine. 0.03 mg/kg aconitine induced arrhythmias in normal rats, while the converted products did not exhibit arrhythmias under an equal dose. In the antiarrhythmic assay, 16-epi-pyroaconitine could dose-dependently delay the onset time of VPB, reduce the incidence of VT, and increase the arrhythmia inhibition rate, demonstrating comparatively strong antiarrhythmic activity. Conclusively, compared with the prototype compound aconitine, the converted products exhibited lower cardiotoxicity. Further investigations on the cardiotoxicity indicated that pyroaconitine with β configuration had a stronger cardiotoxicity than 16-epi-pyroaconitine with α configuration. Furthermore, 16-epi-pyroaconitine could antagonize the arrhythmogenic effect caused by the prototype compound aconitine; the antiarrhythmic effect of 16-epi-pyroaconitine was stronger than lidocaine and propafenone, which had the potential to be developed as antiarrhythmic drugs.

Chemistry and biological activities of hetisine-type diterpenoid alkaloids

Hetisine-type C₂₀-diterpenoid alkaloids (DAs) are one of the most important DA subtypes. During the past decades, a total of 157 hetisine-type DAs were obtained from plants from seven genera in three families, most of which were isolated from the genera Aconitum and Delphinium in the Ranunculaceae family. Structurally, hetisine-type DAs are characterized by a heptacyclic hetisane skeleton formed by the linkage of C(14)–C(20) and N–C(6) bonds in an atisine-type DA, and their structural diversity is created by the states of the N atom and various substituents. Pharmacological studies have revealed a wide range of pharmacological actions for hetisine-type DAs, including antiarrhythmic, antitumor, antimicrobial and insecticidal activities, as well as effects on peripheral vasculature, which are closely related to their chemical structures. In particular, the prominent antiarrhythmic effects and low toxicity of hetisine-type DAs highlight their potential in antiarrhythmic drug discovery. Hetisine-type DAs with diverse bioactivities are promising lead structures for further development as commercial agents in medicine.

Natural hetisine-type C₂₀-diterpenoid alkaloids with diverse structures showed multiple pharmacological activities, indicating great potential in drug discovery.

Isolation, identification, and activity evaluation of diterpenoid alkaloids from Aconitum sinomontanum

A phytochemical study led to the isolation of 25 diterpenoid alkaloids from Aconitum sinomontanum, of which six were described for the first time. Among them compounds 1-3 are anhydrolycoctonine derivatives, rare rearranged aconitine-type C₁₉-diterpenoid alkaloids. To our best knowledge, less than ten of this type of alkaloids were isolated just from the genus Aconitum. The structures of these unreported compounds were elucidated by extensive analysis of NMR spectroscopic data and X-ray diffraction. The biological activities of compounds 1-3, 5-9, and 12-25 were evaluated. Among the tested compounds, compounds 2 and 17 showed potent inhibitory effect on the capsaicin (selective TRPV1 agonist) mediated activation of transient receptor potential vanilloid 1 (TRPV1) channels expressed in HEK-293 cells with inhibition rate of 31.78% and 30.94% at the concentration of 10 μM. Compounds 1-3, 5-9, 13, and 18-25 exhibited weak cytotoxic activity against human tumor cell lines NCI-H226 and MDA-MB-231 with inhibition rate over 10% at the concentration of 10 μM. Compound 16 showed most inhibitory effect on the expression of Nrf2 (NF-E2-related factor-2)-regulated gene with inhibition rate of 25% at the concentration of 20 μM.

Structural diversity, bioactivities, and biosynthesis of natural diterpenoid alkaloids

Covering: 2009 to 2018. Diterpenoid alkaloids, originating from the amination of natural tetracyclic diterpenes, are a diverse class of compounds having complex structural features with many stereocenters. The important pharmacological activities and structural complexity of the diterpenoid alkaloids have long interested scientists due to their medicinal uses, infamous toxicity, and unique biosynthesis. Since 2009, 373 diterpenoid alkaloids, assigned to 46 skeletons, have been isolated and identified from plants mostly in the Ranunculaceae family. The names, classes, molecular weight, molecular formula, NMR data, and plant sources of these diterpene alkaloids are collated here. This review will be a detailed update of the naturally occurring diterpene alkaloids reported from the plant kingdom from 2009-2018, providing an in-depth discussion of their diversity, biological activities, pharmacokinetics, toxicity, application, evolution, and biosynthesis.

Pharmacokinetics of yunaconitine and indaconitine in mouse blood by UPLC-MS/MS

Yunaconitine and indaconitine are active ingredients from the rhizomes of Aconitum plants. In this study, an ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed to measure the concentrations of the yunaconitine and indaconitine in mouse blood, and the method was applied in measuring the pharmacokinetics of the two alkaloids after oral and intravenous administration. A UPLC HSS T3 column (2.1 mm × 100 mm, 1.8 μm particle size) was used for chromatographic separation by gradient elution using acetonitrile-water (0.1% formic acid) as the mobile phase at a flow rate of 0.4 mL/min. Multiple reaction monitoring (MRM) mode and electrospray ionization (ESI) (positive-ion mode) were used to monitor the transitions of each analyte by tandem mass spectrometry for quantitative analysis. Yunaconitine and indaconitine were administered to the mice orally at 2 mg/kg and intravenously at 0.05 mg/kg. Blood was collected at various time intervals, and the blood samples were processed after collection and analyzed by UPLC-MS/MS. The standard curve generated for each analyte was linear over the concentration range of 0.5-500 ng/mL. The intra-day and inter-day accuracy of yunaconitine and indaconitine were 90%-103% and 86%-106%, respectively, and the precision (RSD, %) was less than 15% for both intra-day and inter-day measurements. The matrix effect ranged from 96% to 109%, and the recovery was higher than 72%. The UPLC-MS/MS method developed herein was successfully applied to measuring the pharmacokinetic parameters of yunaconitine and indaconitine in mice after intravenous and oral administration. The bioavailability of yunaconitine and indaconitine were 27.4% and 25.8%, respectively.