The cardiac electrophysiology effects of higenamine in guinea pig heart

Determination of higenamine in common natural spices by ultrahigh-performance liquid chromatography-tandem mass spectrometry

Higenamine (HG) is a β2 receptor agonist and was explicitly added to the Prohibited List of the World Anti-Doping Agency in 2017. This compound is prohibited in both in- and out-of-competition athletes and falls under the category of nonthreshold substances. Because of HG presence in numerous plants, as evidenced by a growing body of research data, an exception was made for HG in the TD2017MRPL document, in which adverse analytical findings (AAFs) were not reported if the urinary HG concentration was less than 10 ng/mL. In this study, a comprehensive and systematic analysis of the HG content in five batches of samples from each of the 48 natural spices selected for this investigation was conducted using UPLC-MS/MS technology. Method validation was carried out in accordance with the ICH Analytical Procedures and Methods Validation for Drugs and Biologics Guidance, and the experimental results demonstrated that the method provided appropriate sensitivity, precision, stability, linearity, and accuracy. HG was detected for the first time in Houttuynia cordata, Zingiber officinale, Cinnamomum cassia, Stevia rebaudiana, Piper nigrum, Siraitia grosuenorii, Platycodon grandiflorus, and Myristica fragrans. Furthermore, the content of HG was found to vary significantly among the different plant parts of Nelumbo nucifera, such as rhizomes, leaves, seeds, and plumules. This paper provides systematic and comprehensive data to support the safe use of spices in athletes' diets, thereby reducing the risk of food-sourced doping violations.

The characteristics and molecular targets of antiarrhythmic natural products

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

Catecholamine Derivatives: Natural Occurrence, Structural Diversity, and Biological Activity

Catecholamines (CAs) are aromatic amines containing a 3,4-dihydroxyphenyl nucleus and an amine side chain. Representative CAs included the endogenous neurotransmitters epinephrine, norepinephrine, and dopamine. CAs and their derivatives are good resources for the development of sympathomimetic or central nervous system drugs, while they also provide ligands important for G-protein coupled receptor (GPCR) research. CAs are of broad interest in the fields of chemical, biological, medical, and material sciences due to their high adhesive capacities, chemical reactivities, metal-chelating abilities, redox activities, excellent biocompatibilities, and ease of degradability. Herein, we summarize CAs derivatives isolated and identified from microorganisms, plants, insects, and marine invertebrates in recent decades, alongside their wide range of reported biological activities. The aim of this review is to provide an overview of the structural and biological diversities of CAs, the regularity of their natural occurrences, and insights toward future research and development pertinent to this important class of naturally occurring compounds.

Roles and mechanisms of natural drugs on sinus node dysfunction

Sinus node dysfunction is a common arrhythmia disorder with a high incidence and significant social and economic burden. Currently, there are no effective drugs for treating chronic sinus node dysfunction. The disease is associated with ion channel disturbances caused by aging, fibrosis, inflammation, oxidative stress, and autonomic dysfunction. Natural active substances and Chinese herbal medicines have been widely used and extensively studied in the medical community for the treatment of arrhythmias. Multiple studies have demonstrated that various active ingredients and Chinese herbal medicines, such as astragaloside IV, quercetin, and ginsenosides, exhibit antioxidant effects, reduce fibrosis, and maintain ion channel stability, providing promising drugs for treating sinus node dysfunction. This article summarizes the research progress on natural active ingredients and Chinese herbal formulas that regulate sick sinoatrial node function, providing valuable references for the treatment of sinus node dysfunction.

Chemical constituents, pharmacological effects, toxicology, processing and compatibility of Fuzi (lateral root of Aconitum carmichaelii Debx): A review

ETHNOPHARMACOLOGICAL RELEVANCE

The lateral root of Aconitum carmichaelii Debx is known as Fuzi in Chinese. It is traditionally valued and used for dispelling cold, relieving pain effects, restoring 'Yang,' and treating shock despite its high toxicity. This review aims to provide comprehensive information on the chemical composition, pharmacological research, preparation, and compatibility of Fuzi to help reduce its toxicity and increase its efficiency, based on the scientific literature. In addition, this review will establish a new foundation for further studies on Fuzi.

MATERIALS AND METHODS

A systematic review of the literature on Fuzi was performed using several resources, namely classic books on Chinese herbal medicine and various scientific databases, such as PubMed, the Web of Science, and the China Knowledge Resource Integrated databases.

RESULTS

Fuzi extracts contain diester-type alkaloids, monoester-type alkaloids, other types of alkaloids, and non-alkaloids types, and have various pharmacological activities, such as strong heart effect, effect on blood vessels, and antidepressant, anti-diabetes, anti-inflammatory, pain-relieving, antitumor, immunomodulatory, and other therapeutic effects. However, these extracts can also lead to various toxicities such as cardiotoxicity, neurotoxicity, reproductive toxicity, hepatotoxicity, and embryonic toxicity. In vivo and in vitro experiments have demonstrated that different processing methods and suitable compatibility with other herbs can effectively reduce the toxicities and increase the efficiency of Fuzi.

CONCLUSION

The therapeutic potential of Fuzi has been demonstrated in conditions, such as heart failure, various pains, inflammation, and tumors, which is attributed to the diester-type alkaloids, monoester-type alkaloids, other types of alkaloids, and non-alkaloid types. In contrast, they are also toxic components. Proper processing and suitable compatibility can effectively reduce toxicity and increase the efficiency of Fuzi. Thus more pharmacological and toxicological mechanisms on main active compounds are necessary to be explored.

Dietary higenamine from Annonaceae family fruits as a possible source of unintentional doping

Members of the genus Aconitum have been used for millennia, both as poisons and medicines, in Eastern culture. Higenamine has non-selective beta-agonist effects, activating both β₁ and β₂ adrenoreceptors, and is present in a variety of plants. The World Anti-Doping Agency has banned Higenamine both in competition and out of competition. Due to the common uses of higenamine in Brazilian culture, both as medicine and food, we studied the urinary concentrations of higenamine after the consumption of fruits of the Annona genus. We evaluated whether the ingestion of these fruits has the potential to cause anti-doping code violations. We measured higenamine concentrations for a 72 h period in the urine of ten healthy, physically active males (age 20-30; weight 70-80 kg; not consuming supplements or medications) after eating a unique meal containing fruits. Fruit consumption ranges were: Carica papaya (control) 348 ± 98 g; A. muricata 450 ± 282 g; and A. squamosa 314 ± 60 g. (all mean± SD). Higenamine was measured using ultra-performance liquid chromatography coupled with electrospray-tandem mass spectrometry. The appearance of urinary higenamine occurred within the first 12 h after eating A. muricata (n = 3), and the maximum concentration found was 1.9 ng/mL. The ingestion of A. squamosa has also been shown to cause higenamine urinary excretion. The elimination kinetics of the subjects who ingested A. squamosa (n = 4) were different from each other. After ingestion of the control fruit, C. papaya, we detected no higenamine in the urine of any participants (n = 3). Although the kinetics varied by individuals and fruits, A. muricata ingestion produced higher higenamine excretion; however, the A. squamosa portion weighed ∼66 % of the A. muricata portion. We conclude that eating Annonaceae family fruits cause detectable higenamine excretion. Conversely, single ingestion did not reach the WADA's threshold to cause adverse analytical findings.

Pharmacological effects of higenamine based on signalling pathways and mechanism of action

Higenamine (HG) is a chemical compound found in various plants, such as aconite. Recent pharmacological studies have demonstrated its effectiveness in the management of many diseases. Several mechanisms of action of HG have been proposed; however, they have not yet been classified. This review summarises the signalling pathways and pharmacological targets of HG, focusing on its potential as a naturally extracted drug. Articles related to the pharmacological effects, signalling pathways and pharmacological targets of HG were selected by searching the keyword “Higenamine” in the PubMed, Web of Science and Google Scholar databases without limiting the search by publication years. HG possesses anti-oxidant, anti-apoptotic, anti-inflammatory, electrophysiology regulatory, anti-fibrotic and lipid-lowering activities. It is a structural analogue of catecholamines and possesses characteristics similar to those of adrenergic receptor ligands. It can modulate multiple targets, including anti-inflammation- and anti-apoptosis-related targets and some transcription factors, which directly or indirectly influence the disease course. Other naturally occurring compounds, such as cucurbitacin B (Cu B) and 6-gingerol (6-GR), can be combined with HG to enhance its anti-apoptotic activity. Although significant research progress has been made, follow-up pharmacological studies are required to determine the exact mechanism of action, new signalling pathways and targets of HG and the effects of using it in combination with other drugs.

Use of UPLC-MS/MS for determination of higenamine in urine following oral administration of traditional Chinese medicine

Since higenamine (HG) was first included in the World Anti-doping Agency (WADA) 2017 Prohibited List, an increasing number of plants have been found to contain this ingredient. As a result, doctors are hesitant to prescribe traditional Chinese medicine (TCM) to athletes. Thus, it is very important to assess the risks of doping violations due to HG following the oral administration of TCM. We determined the drug concentration-time curves for HG in urine by liquid chromatography-tandem mass spectrometry (LC-MS/MS) after single or multiple administrations of lotus seed powder on volunteers, the single dose was equivalent to 750 μg of HG, the multiple doses were equivalent to 90 μg of HG each, 3 times daily for 5 consecutive days. For the single-dose group, the HG could be detected in urine 0.5 hours after administration and reached a maximum concentration of 16.5 ng/ml 1 hour after administration. For the multiple-dose group, the HG concentrations in urine showed two peaks at 29 and 77 hours post-administration with 22.6 and 23.1 ng/mL, respectively. At the dosage used in this study, the maximum concentration of HG in some urine samples exceeded the WADA limit of 10.0 ng/mL; the risk was still very high, so athletes must avoid this amount of HG when using TCM. In addition, our study provided further data supporting the presence of sulfonated metabolites of HG in urine samples.

Bronchodilatory effect of higenamine as antiallergic asthma treatment

Asthma is a complex airway disease that affects more than 350 million humans worldwide. Allergic asthma symptoms are induced by Th2 immune response with the release of cytokines and allegro-inflammatory mediators that amplify the inflammatory response, airway hyper-responsiveness (AHR) and hyperproduction of mucus. Higenamine, as a chemical compound, is a β₂ adrenoreceptor agonist and can be used as bronchodilator in allergic asthma.BALB/c mice were allocated in four groups and then allergic asthma was induced in three groups. One of the asthmatic groups was treated with albuterol and other one was treated with higenamine. At least, methacholine challenge to determine the AHR, measurement of cytokines, total immunoglobulin E (IgE), LTB4 and LTC4 levels, evaluation of gene expression of Muc5ac, Muc5b, Agr2 and Arg1, and histopathological study were done.Higenamine treatment reduced AHR, interleukin (IL)-4, IL-13 levels, mRNA expression of MUC5ac, MUC5b, Arg1 and Agr2, goblet cell hyperplasia and mucus hypersecretion. Higenamine had no significant effect on IL-5, interferon-γ (INF-γ), IgE, LTB4, LTC4 levels and eosinophilic inflammation in lung tissue.Higenamine treatment controls asthma acute attack and breathlessness and can be used as asthma treatment with control of AHR and decrease of airflow obstruction and mucus hypersecretion and had allegro-immune-regulatory effect. But higenamine treatment had no notable effect on the inflammation and inflammatory factors.

Role of Higenamine in Heart Diseases: A Mini-Review

Higenamine, a natural product with multiple targets in heart diseases, is originally derived from Aconitum, which has been traditionally used in China for the treatment of heart disease, including heart failure, arrhythmia, bradycardia, cardiac ischemia/reperfusion injury, cardiac fibrosis, etc. This study is aimed to clarify the role of higenamine in heart diseases. Higenamine has effects on improving energy metabolism of cardiomyocytes, anti-cardiac fibroblast activation, anti-oxidative stress and anti-apoptosis. Accumulating evidence from various studies has shown that higenamine exerts a wide range of cardiovascular pharmacological effects in vivo and in vitro, including alleviating heart failure, reducing cardiac ischemia/reperfusion injury, attenuating pathological cardiac fibrosis and dysfunction. In addition, several clinical studies have reported that higenamine could continuously increase the heart rate levels of healthy volunteers as well as patients with heart disease, but there are variable effects on systolic blood pressure and diastolic blood pressure. Moreover, the heart protection and therapeutic effects of higenamine on heart disease are related to regulating LKB1/AMPKα/Sirt1, mediating the β2-AR/PI3K/AKT cascade, induction of heme oxygenase-1, suppressing TGF-β1/Smad signaling, and targeting ASK1/MAPK (ERK, P38)/NF-kB signaling pathway. However, the interventional effects of higenamine on heart disease and its underlying mechanisms based on experimental studies have not yet been systematically reviewed. This paper reviewed the potential pharmacological mechanisms of higenamine on the prevention, treatment, and diagnosis of heart disease and clarified its clinical applications. The literature shows that higenamine may have a potent effect on complex heart diseases, and proves the profound medicinal value of higenamine in heart disease.

Therapeutic effects of higenamine combined with [6]-gingerol on chronic heart failure induced by doxorubicin via ameliorating mitochondrial function

Higenamine (HG) is a natural benzylisoquinoline alkaloid isolated from Aconitum with positive inotropic and chronotropic effects. This study aimed to investigate the possible cardioprotective effects of HG combined with [6]-gingerol (HG/[6]-GR) against DOX-induced chronic heart failure (CHF) by comprehensive approaches. DOX-induced cardiotoxicity model in rats and H9c2 cells was established. Therapeutic effects of HG/[6]-GR on haemodynamics, serum indices and histopathology of cardiac tissue were analysed. Cell mitochondrial energy phenotype and cell mitochondrial fuel flex were measured by a Seahorse XFp analyser. Moreover, UHPLC-Q-TOF/MS was performed to explore the potential metabolites affecting the therapeutic effects and pathological process of CHF. To further investigate the potential mechanism of HG/[6]-GR, mRNA and protein expression levels of RAAS and LKB1/AMPK/Sirt1-related pathways were detected. The present data demonstrated that the therapeutic effects of HG/[6]-GR combination on CHF were presented in ameliorating heart function, down-regulation serum indices and alleviating histological damage of heart tissue. Besides, HG/[6]-GR has an effect on increasing cell viability of H9c2 cells, ameliorating DOX-induced mitochondrial dysfunction and elevating mitochondrial OCR and ECAR value. Metabolomics analyses showed that the therapeutic effect of HG/[6]-GR combination is mainly associated with the regulation of fatty acid metabolites and energy metabolism pathways. Furthermore, HG/[6]-GR has an effect on down-regulating RAAS pathway-related molecules and up-regulating LKB1/AMPKα/Sirt1-related pathway. The present work demonstrates that HG/[6]-GR prevented DOX-induced cardiotoxicity via the cardiotonic effect and promoting myocardial energy metabolism through the LKB1/AMPKα/Sirt1 signalling pathway, which promotes mitochondrial energy metabolism and protects against CHF.

Higenamine exerts an antispasmodic effect on cold-induced vasoconstriction by regulating the PI3K/Akt, ROS/α2C-AR and PTK9 pathways independently of the AMPK/eNOS/NO axis

The present study aimed to investigate the antispasmodic effect of higenamine on cold-induced cutaneous vasoconstriction and the underlying molecular mechanisms. A cold-induced cutaneous vasoconstriction rat model was established and different doses of higenamine were delivered by intravenous injection. The changes of cutaneous regional blood flow (RBF) between groups were analyzed. In vitro, the proliferation of human dermal microvascular endothelial cells was measured by MTT. The NO concentration was detected by a nitrate reductase assay. Flow cytometry was applied to measure reactive oxygen species (ROS) levels. The protein expression levels were detected by western blotting. The results demonstrated that in the model group, RBF declined compared with the normal control group, but was reversed by treatment with higenamine. The expression of endothelial nitric oxide synthase (eNOS), phosphorylated (p)-eNOS, protein kinase B (Akt1), p-Akt1, AMP-activated protein kinase (AMPK) α1 and p-AMPKα1 was upregulated by hypothermic treatment but was reversed by higenamine treatment. Treatment with higenamine significantly reduced the level of intracellular α2C-adrenoreceptor (AR) compared with the hypothermia group (P<0.05). Furthermore, the expression of twinfilin-1 (PTK9) was downregulated in the higenamine and positive control groups compared with the hypothermia group (P<0.05). Compared with the hypothermia group, the levels of ROS and α2C-AR (intracellular & membrane) were decreased in higenamine and the positive control group (P<0.05 and P<0.01, respectively). This study, to the best of our knowledge, is the first to assess the effects of higenamine on cold-induced vasoconstriction in vivo and its molecular mechanisms on the PI3K/Akt, AMPK/eNOS/nitric oxide, ROS/α2C-AR and PTK9 signaling pathways under hypothermia conditions. Higenamine may be a good therapeutic option for Raynaud's phenomenon (RP) and cold-induced vasoconstriction.