Aconitine - A promising candidate for treating cold and mechanical allodynia in cancer induced bone pain.

BACKGROUND AND AIMS: Patients suffering from cancer induced bone pain (CIBP) have a poor quality of life that is exacerbated by the lack of effective therapeutic drugs. Monkshood is a flowering plant that has been used in traditional Chinese medicine where it has been used to relieve cold pain. Aconitine is the active component of monkshood, but the molecular mechanism for how this compound reduces pain is unclear. METHODS AND RESULTS: In this study, we employed molecular and behavioral experiments to explore the analgesic effect of aconitine. We observed aconitine alleviated cold hyperalgesia and AITC (allyl-isothiocyanate, TRPA1 agonist) induced pain. Interestingly, we found aconitine directly inhibits TRPA1 activity in calcium imaging studies. More importantly, we found aconitine alleviated cold and mechanical allodynia in CIBP mice. Both the activity and expression of TRPA1 in L4 and L5 DRG (Dorsal Root Ganglion) neurons were reduced with the treatment of aconitine in the CIBP model. Moreover, we observed aconiti radix (AR) and aconiti kusnezoffii radix (AKR), both components of monkshood that contain aconitine, alleviated cold hyperalgesia and AITC induced pain. Furthermore, both AR and AKR alleviated CIBP induced cold allodynia and mechanical allodynia. CONCLUSIONS: Taken together, aconitine alleviates both cold and mechanical allodynia in cancer induced bone pain via the regulation of TRPA1. This research on the analgesic effect of aconitine in cancer induced bone pain highlights a component of a traditional Chinese medicine may have clinical applications for pain.

A New Strategy for the Rapid Identification and Validation of the Direct Targets of Aconitine-Induced Cardiotoxicity.

BACKGROUND: The interaction of small molecules with direct targets constitutes the molecular initiation events of drug efficacy and toxicity. Aconitine, an active compound of the Aconitum species, has various pharmacological effects but is strongly toxic to the heart. The direct targets of aconitine-induced cardiotoxicity remain unclear. METHODS: We predicted the toxic targets of aconitine based on network pharmacology and followed a novel proteomic approach based on the "drug affinity responsive target stability" technology combined with LC-MS/MS to identify the direct targets of aconitine. The identified targets were analysed from the perspective of multilevel and multidimensional bioinformatics through a network integration method. The binding sites were investigated via molecular docking to explore the toxicity mechanism and predict the direct targets of aconitine. Finally, atomic force microscopy (AFM) imaging was performed to verify the affinity of aconitine to the direct targets. RESULTS: PTGS2, predicted by network pharmacology as a toxic target, encodes cyclooxygenase 2 (COX-2), which is closely related to myocardial injury. Furthermore, cytosolic phospholipase A2 (cPLA2) is the upstream signal protein of PTGS2, and it is a key enzyme in the metabolism of arachidonic acid during an inflammatory response. We determined cPLA2 as a direct target, and AFM imaging verified that aconitine could bind to cPLA2 well; thus, aconitine may cause the expression of PTGS2/COX-2 and release inflammatory factors, thereby promoting myocardial injury and dysfunction. CONCLUSION: We developed a complete set of methods to predict and verify the direct targets of aconitine, and cPLA2 was identified as one. Overall, the novel strategy provides new insights into the discovery of direct targets and the molecular mechanism of toxic components that are found in traditional Chinese medicine.

Cardiac efficacy and toxicity of aconitine: A new frontier for the ancient poison.

Aconitine (AC) is well-known as the main toxic ingredient and active compound of Aconitum species, of which several aconites are essential herbal medicines of Traditional Chinese Medicine (TCM) and widely applied to treat diverse diseases for their excellent anti-inflammatory, analgesic, and cardiotonic effects. However, the cardiotoxicity and neurotoxicity of AC attracted a lot of attention and made it a favorite botanic poison in history. Nowadays, the narrow therapeutic window of AC limits the clinical application of AC-containing herbal medicines; overdosing on AC always induces ventricular tachyarrhythmia and heart arrest, both of which are potentially lethal. But the underlying cardiotoxic mechanisms remained chaos. Recently, beyond its cardiotoxic effects, emerging evidence shows that low doses of AC or its metabolites could generate cardioprotective effects and are necessary to aconite's clinical efficacy. Consistent with TCM's theory that even toxic substances are powerful medicines, AC thus could not be simply identified as a toxicant or a drug. To prevent cardiotoxicity while digging the unique value of AC in cardiac pharmacology, there exists a huge urge to better know the characteristic of AC being a cardiotoxic agent or a potential heart drug. Here, this article reviews the advances of AC metabolism and focuses on the latest mechanistic findings of cardiac efficacy and toxicity of this aconite alkaloid or its metabolites. We also discuss how to prevent AC-related cardiotoxicity, as well as the issues before the development of AC-based medicines that should be solved, to provide new insight into the paradoxical nature of this ancient poison.

Ginsenoside Rb1 ameliorates cardiotoxicity triggered by aconitine via inhibiting calcium overload and pyroptosis.

BACKGROUND: Aconitine-induced cardiotoxicity limits the clinical treatment of cardiotonic, cancers and immune-related diseases. Ginsenoside Rb1 (Rb1) is an active ingredient of traditional Chinese medicine with cardioprotective effect. PURPOSE: This study aims to study the mechanism of aconitine cardiotoxicity and the detoxification mechanism of Rb1. STUDY DESIGN: METHODS: The regulatory effect of Rb1 on aconitine was evaluated in vitro and in vivo by myocardial enzyme indicators, pathological analysis, CardioECR detection, calcium transient analysis, western blotting and immunohistochemistry. RESULTS: Rb1 (10, 20, 40 mg/kg) alleviated apoptotic myocardial damage caused by aconitine in rats. Furthermore, Rb1 (25, 50, 100 µM) restored the contractile function and field potential of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) by regulating calcium channels and reduced myocardial cell damage by inhibiting the calcium transients of adult rat ventricular myocytes (ARVMs). Rb1 significantly reduced calcium levels in hiPSC-CMs, directly indicating that aconitine-induced calcium overload was alleviated by Rb1. Further, aconitine caused calcium overload by changing the expression of calcium pathway proteins, while Rb1 effectively restored calcium homeostasis. In addition, Rb1 also had a cardioprotective role by inhibiting cell pyroptosis. These results suggested that the maintenance of calcium homeostasis helped to suppress the inflammatory response related to pyroptosis of the heart. CONCLUSION: Aconitine-induced cardiotoxicity can be alleviated by Rb1 via restoring calcium homeostasis and inhibiting apoptosis and pyroptosis.

[Establishment and verification of risk assessment scale for clinical safety medication of aconitine].

Chinese patent medicine containing aconitine is the key in clinical rational drug use. These drugs contain Chuanwu, Caowu or Fuzi, and Aconitum brachypodum with functions of expelling wind-dampness or tonifying Yang, all of which shall be used by strictly following the indications and dosage. However, there are many kinds of such drugs. Not only the unfamiliar knowledge of some Chinese and Western physicians about the characteristics of them, but also the combination of multiple drugs from different clinical departments, would increase the risk of aconitine poisoning. Based on the previous research, this paper proposed three core elements "syndrome differentiation-dosage differentiation-toxicity differentiation" from the prescription review and pharmacy consulting work, and objective and standardized evaluation was used to build a risk assessment scale containing 3 categories, 9 items and 36 indicators with Hulisan Jiaonang and Qufeng Zhitong Jiaonang as the example. This scale was used to evaluate the risk of a therapeutic regimen before and after the implementation. According to the verification of the existing adverse reaction cases, the risk assessment scale can be used to indicate the risk of drug treatment program and identify the risk level of drug treatment status. This paper tried to provide a methodological paradigm for scientific and objective evaluation on the safety of Chinese patent medicines, and help to identify the key links and risk prevention in the rational use by Chinese medicine physicians and pharmacists.

Assessment of in vitro cardiotoxicity of extract fractions and diterpene alkaloids from Aconitum leucostomum Worosch: A short communication.

Aconitum leucostomum Worosch is a traditional Chinese medicine (TCM) and has a broad spectrum of health effects, but with a narrow therapeutic window. It is important to identify both the therapeutic ingredients and the toxic components to better utilize this TCM. The present study investigated the cardiotoxicity of the selected compounds in Aconitum leucostomum Worosch. The effects of extract of A. leucostomum Worosch and the isolated compounds on cardiocardiomyocytes were evaluated in vitro. Five known compounds in this TCM, including three C18-diterpene alkaloids, lappaconitine (2), N-deacetyllappaconitine (3), and ranaconitine (5), and two C19-diterpene alkaloids, delvestidine (1) and anthranoyllycoctonine (4), were isolated from A. leucostomum Worosch. The cardiotoxicity of these components and extract fractions, as measured by lactate dehydrogenase release and apoptosis, was ranked as follows, in descending order: delvestidine>anthranoyllycoctonine>pH 4 fraction>pH 8 fraction>aconitine>N-deacetyllappaconitine>ranaconitine>lappaconitine. The cytotoxicity of these compounds was shown to be dose-dependent, with delvestidine (1) and anthranoyllycoctonine (4) being the two most toxic compounds to cardiomyocytes in our assays. These results provide a basis for future rational use of this TCM, reducing side effects while retaining therapeutic effects.

Observation on effects of aconitine via acupoint injection in rabbits.

OBJECTIVE: To investigate the ability of the pericardium meridian (PM) to mitigate or enhance the cardiotoxic effects of aconitine injected at specific acupoint and non-acupoint sites in rabbits. METHODS: This study consisted of 3 experiments that were designed to test the effects of injection of 30 µg/kg of aconitine at acupoints on the PM (Test 1), at non-acupoint sites on the PM (Test 2), and at acupoints on other meridians and non-meridian sites (Test 3). In Test 1, 24 rabbits were randomly assigned to receive injections at Quze (PC3), Tianquan (PC2), or intramuscularly. In Test 2, 24 rabbits were randomly assigned to receive injections of aconitine at non-acupoint I, non-acupoint II, or intramuscularly. In Test 3, 48 rabbits were randomly assigned to receive injections at Neiguan (PC6), Sanyinjiao (SP6), Yangjiao (GB35), a non-meridian and non-acupoint site (NMNA), intravenously, and intramuscularly. Electrocardiographs of the rabbits were performed before, during and after injection to determine the incidence of arrhythmia, latency of ventricular rhythm, and recovery rate after aconitine injection. The recovery time index and extent of arrhythmia scores were calculated. RESULTS: In all groups the incidence of arrhythmia was 100%, and the latency of ventricular rhythm was less than 30 min. In Tests 1 and 2, the recovery rates of the Quze and non-acupoint II groups were significantly higher than those of the muscular group (P < 0.05). In Test 3, the recovery time index and extent of arrhythmia scores of the Neiguan group were low. There were no significant differences between the other acupoint groups, or the NMNA group, when compared with the group receiving aconitine intramuscularly. CONCLUSIONS: Acupoints or non-acupoints along the PM could reduce the severity of the arrhythmia induced by aconitine in healthy rabbits. Meridians play an important role in protecting body functions.

[Antiarrhythmic therapy of paroxysmal tachycardias and extrasystoles in patients with sinus node dysfunction].

Antiarrhythmic therapy of patients with disturbed automatism of the sinus node and impaired atrioventricular conductance may be complicated by hemodynamically significant bradycardias and contraindications for implantation of a cardiac electrical stimulator This study aimed at estimating effect of antiarrhythmic therapy with allapinin on the function of sinus and atrioventricular nodes. It included 20 patients (mean age 37.5+-2.3 years) with disturbed cardiac rhythm and sinus node dysfunction treated with allapinin (37.5 - 50 mg/d per os). This therapy had well apparent antiarrhythmic effect manifest as improvement of supraventricular and ventricular ectopic activities in the absence of negative influence on the function of sinus and atrioventricular nodes.

Aconitum in traditional Chinese medicine: a valuable drug or an unpredictable risk?

Aconitum species have been used in China as an essential drug in Traditional Chinese Medicine (TCM) for 2000 years. Reviewing the clinical application of Aconitum, their pharmacological effects, toxicity and detoxifying measures, herb-herb interactions, clinical taboos, famous herbal formulas, traditional and current herbal processing methods based upon a wide range of literature investigations serve as a case study to explore the multidisciplinary implications of botanicals used in TCM. The toxicological risk of improper usage of Aconitum remains very high, especially in countries like China, India and Japan. The toxicity of Aconitum mainly derives from the diester diterpene alkaloids (DDAs) including aconitine (AC), mesaconitine (MA) and hypaconitine (HA). They can be decomposed into less or non-toxic derivatives through Chinese traditional processing methods (Paozhi), which play an essential role in detoxification. Using Paozhi, the three main forms of processed aconite -- yanfuzi, heishunpian and baifupian -- can be obtained (CPCommission, 2005). Moreover, some new processing techniques have been developed in China such as pressure-steaming. The current development of fingerprint assays, in particular HPLC, has set a good basis to conduct an appropriate quality control for TCM crude herbs and their ready-made products. Therefore, a stipulation for a maximum level of DDA content of Aconitum is highly desirable in order to guarantee the clinical safety and its low toxicity in decoctions. Newly developed HPLC methods have made the accurate and simultaneous determination and quantification of DDA content interesting.

[Some aspects of the antiarrhythmic effect of glialin].

The antiarrhythmic activity of allapinine and glialin (a complex of allapinin and glycyrrhizic acid) was studied on models of arrhythmias induced in rats and guinea pigs by intravenous administration of calcium chloride, aconitine, barium chloride, and strophanthin. The antiarrhythmic activity of glialin is qualitatively analogous to that of allapinine. The advantage of glialin over allapinin is its low toxicity, which is due to the presence of glycyrrhizic acid.

Toxicity following accidental ingestion of Aconitum containing Chinese remedy.

Various species of Aconitum are commonly used in traditional Chinese medicine. These plants are known to contain highly potent cardiotoxins. A 22 year old Chinese male accidentally ingested a herbal liniment prepared from Aconitum with near fatal results. His ventricular tachyarrhythmias responded to standard treatment including the use of i.v. magnesium.

[Effect of electric cardiac stimulation in experimental supraventricular tachycardia]. / Uber die Wirkung der elektrischen Reizung des Herzens bei experimenteller supraventrikulärer Tachyarrhythmie.

Experimental supraventricular tachyarrhythmia was produced in dogs by the local application of aconitine on the left auricle. The effect of various types of stimulations (right auricular, right ventricular, double-delayed right auricular and right ventricular-right auricular double-delayed stimulation) was studied for the suppression of supra-ventricular (overdrive) tachyarrhythmia. It was found that the electric stimulation of the heart is an effective method of suppressing tachyarrhythmias, though there is a significant difference in the anti-arrhythmic effects of the electric stimulations of various types. For suppression of the supraventricular tachyarrhythmia caused by aconitine, delayed double-right auricular stimulation seemed to be the most effective with respect to the right ventricle. The bioelectric features of aconitine arrhythmia and the mechanism of the antiarrhythmic effect of the electric stimulation of the heart are discussed.