Aconitine Induces TRPV2-Mediated Ca2+ Influx through the p38 MAPK Signal and Promotes Cardiomyocyte Apoptosis

Treatment of a patient with aconitine poisoning using veno-arterial membrane oxygenation: A case report

BACKGROUND

Aconitine poisoning is highly prone to causing malignant arrhythmias. The elimination of aconitine from the body takes a considerable amount of time, and during this period, patients are at a significant risk of death due to malignant arrhythmias associated with aconitine poisoning.

CASE SUMMARY

A 30-year-old male patient was admitted due to accidental ingestion of aconitine-containing drugs. Upon arrival at the emergency department, the patient intermittently experienced malignant arrhythmias including ventricular tachycardia, ventricular fibrillation, ventricular premature beats, and cardiac arrest. Emergency interventions such as cardiopulmonary resuscitation and defibrillation were promptly administered. Additionally, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) therapy was initiated. Successful resuscitation was achieved before ECMO placement, but upon initiation of ECMO, the patient experienced recurrent malignant arrhythmias. ECMO was utilized to maintain hemodynamics and respiration, while continuous blood purification therapy for toxin clearance, mechanical ventilation, and hypothermic brain protection therapy were concurrently administered. On the third day of VA-ECMO support, the patient’s respiratory and hemodynamic status stabilized, with only frequent ventricular premature beats observed on electrocardiographic monitoring, and echocardiography indicated recovery of cardiac contractile function. On the fourth day, a significant reduction in toxin levels was observed, along with stable hemodynamic and respiratory functions. Following a successful pump-controlled retrograde trial occlusion test, ECMO assistance was terminated. The patient gradually improved postoperatively and achieved recovery. He was discharged 11 days later.

CONCLUSION

VA-ECMO can serve as a bridging resuscitation technique for patients with reversible malignant arrhythmias.

A toxicological review of alkaloids

Alkaloids are naturally occurring compounds with complex structures found in natural plants. To further improve the understanding of plant alkaloids, this review focuses on the classification, toxicity and mechanisms of action, providing insight into the occurrence of alkaloid-poisoning events and guiding the safe use of alkaloids in food, supplements and clinical applications. Based on their chemical structure, alkaloids can be divided into organic amines, diterpenoids, pyridines, isoquinolines, indoles, pyrrolidines, steroids, imidazoles and purines. The mechanisms of toxicity of alkaloids, including neurotoxicity, hepatoxicity, nephrotoxicity, cardiotoxicity and cytotoxicity, have also been reviewed. Some cases of alkaloid poisoning have been introduced when used as food or clinically, including accidental food poisoning, excessive consumption, and poisoning caused by the improper use of alkaloids in a clinical setting, and the importance of safety evaluation was illustrated. This review summarizes the toxicity and mechanism of action of alkaloids and provides evidence for the need for the safe use of alkaloids in food, supplements and clinical applications.

Integrated virtual screening and in vitro studies for exploring the mechanism of triterpenoids in Chebulae Fructus alleviating mesaconitine-induced cardiotoxicity via TRPV1 channel

Background: In traditional Mongolian or Tibetan medicine in China, Chebulae Fructus (CF) is widely used to process or combine with aconitums to decrease the severe toxicity of aconitums. Researches in this area have predominantly focused on tannins, with few research on other major CF components for cardiotoxicity mitigation. The present study aimed to clarify whether triterpenoids can attenuate the cardiotoxicity caused by mesaconitine (MA) and investigate the mechanism of cardiotoxicity attenuation. Methods: Firstly, the pharmacophore model, molecular docking, and 3D-QSAR model were used to explore the mechanism of CF components in reducing the toxicity of MA mediated by the TRPV1 channel. Then three triterpenoids were selected to verify whether the triterpenoids had the effect of lowering the cardiotoxicity of MA using H9c2 cells combined with MTT, Hoechst 33258, and JC-1. Finally, Western blot, Fluo-3AM, and MTT assays combined with capsazepine were used to verify whether the triterpenoids reduced H9c2 cardiomyocyte toxicity induced by MA was related to the TRPV1 channel. Results: Seven triterpenoids in CF have the potential to activate the TRPV1 channel. And they exhibited greater affinity for TRPV1 compared to other compounds and MA. However, their activity was relatively lower than that of MA. Cell experiments revealed that MA significantly reduced H9c2 cell viability, resulting in diminished mitochondrial membrane potential and nuclear pyknosis and damage. In contrast, the triterpenoids could improve the survival rate significantly and counteract the damage of MA to the cells. We found that MA, arjungenin (AR), and maslinic acid (MSA) except corosolic acid (CRA) upregulated the expression of TRPV1 protein. MA induced a significant influx of calcium, whereas all three triterpenoids alleviated this trend. Blocking the TRPV1 channel with capsazepine only increased the cell viability that had been simultaneously treated with MA, and AR, or MSA. However, there was no significant difference in the CRA groups treated with or without capsazepine. Conclusion: The triterpenoids in CF can reduce the cardiotoxicity caused by MA. The MSA and AR function as TRPV1 agonists with comparatively reduced activity but a greater capacity to bind to TRPV1 receptors, thus antagonizing the excessive activation of TRPV1 by MA.

An Updated Meta-Analysis Based on the Preclinical Evidence of Mechanism of Aconitine-Induced Cardiotoxicity

Background: Most Aconitum species in traditional Chinese medicine have the effect of dispelling wind, dehumidifying, warming the meridian, and relieving pain. Aconitine is the characteristic chemical component with the function of anti-inflammation, analgesic, and heart-strengthening effects. However, improper use will produce cardiotoxicity and neurotoxicity. Currently, the mechanisms of cardiotoxicity caused by aconitine are wheels within wheels without being fully disclosed. The systematic review and meta-analysis were therefore conducted to summarize the available evidence of myocardial toxicity caused by aconitine.

Methods: We searched PubMed, Embase, Web of Science, National Knowledge Infrastructure, WANFANG, and VIP information database for relevant preclinical studies. All the data were analyzed by RevMan version 5.3.

Results: Thirty-two studies met the final inclusion criteria, including both in vivo and in vitro study types. After aconitine treatment, the heart rate of animals was obviously abnormal, and the morphology and function of myocardial cells were significantly changed. Aconitine can induce changes in the electrophysiological activity of cardiac myocytes by regulating Na⁺, Ca²⁺, and K⁺ currents. Meanwhile, the mechanisms of cardiotoxicity of aconitine may be related to triggering mitochondrial dysfunction by inducing mitochondrial apoptosis and autophagy. It should not be ignored that the overactivation of NLRP3 inflammasome also exacerbates aconitine’s cardiotoxicity.

Conclusion: The altered ion channels and mitochondrial function, as well as the signaling pathways interacting with NLRP3, may deserve further study for aconitine-induced cardiotoxicity.

Gallic Acid Inhibits Mesaconitine-Activated TRPV1-Channel-Induced Cardiotoxicity

Aconiti Kusnezoffii Radix (Caowu) is often combined or processed with Chebulae Fructus (Hezi) to achieve attenuation purposes in Mongolian medicine. Mesaconitine (MA), a main bioactive ingredient of Caowu, is also famous for its high cardiotoxicity while exerting good anti-inflammatory and analgesic properties. Gallic acid (GA), one of the leading chemical components in Hezi, possesses cardiac protection. This study aimed to clarify the detoxification effects of GA from Hezi on MA-induced cardiotoxicity and whether the detoxification mechanism is related to the TRPV1 channel. Cell viability was determined by methyl thiazol tetrazolium (MTT), and lactate dehydrogenase (LDH) leakage rate was determined by ELISA. Hoechst 33258, JC-1, DCFH-DA, and Fluo-3 AM staining were conducted to detect apoptosis, mitochondrial membrane potential, reactive oxygen species (ROS), and Ca2+ respectively; TRPV1 channel current was recorded by whole-cell patch-clamp technology to observe the effect of GA and MA alone or in combination on TRPV1 channel. The results showed that GA exhibited pronounced detoxification effects on MA-induced cardiotoxicity. GA significantly inhibited the MA-induced decrease in cell viability; suppressed the MA-induced LDH leakage rate, apoptosis, and the release of ROS and Ca2+; and alleviated the reduction of mitochondrial membrane potential. We found that MA-induced cardiotoxicity was significantly attenuated in H9c2 cells pretreated with the TRPV1 antagonist BCTC. In the whole-cell patch-clamp experiment, the TRPV1 channel current increase was caused by the GA and MA treatment, whereas it was reduced by the cotreatment of GA and MA. Our data demonstrate that GA in Hezi can reduce MA-induced cardiotoxicity by inhibiting intracellular Ca2+ influx, restoring mitochondrial membrane potential, and reducing apoptosis. The detoxification mechanism may be related to the desensitization of the TRPV1 channel by the combined application of MA and GA.