Amiodarone hepatotoxicity with absent phospholipidosis and steatosis: a case report and review of amiodarone toxicity in various organs

Livogrit prevents Amiodarone-induced toxicity in experimental model of human liver (HepG2) cells and Caenorhabditis elegans by regulating redox homeostasis

Treatment with cationic amphiphilic drugs like Amiodarone leads to development of phospholipidosis, a type of lysosomal storage disorder characterized by excessive deposition of phospholipids. Such disorder in liver enhances accumulation of drugs and its metabolites, and dysregulates lipid profiles, which subsequently leads to hepatotoxicity. In the present study, we assessed pharmacological effects of herbal medicine, Livogrit, against hepatic phospholipidosis-induced toxicity. Human liver (HepG2) cells and in vivo model of Caenorhabditis elegans (N2 and CF1553 strains) were used to study effect of Livogrit on Amiodarone-induced phospholipidosis. In HepG2 cells, Livogrit treatment displayed enhanced uptake of acidic pH-based stains and reduced phospholipid accumulation, oxidative stress, AST, ALT, cholesterol levels, and gene expression of SCD-1 and LSS. Protein levels of LPLA2 were also normalized. Livogrit treatment restored Pgp functionality which led to decreased cellular accumulation of Amiodarone as observed by UHPLC analysis. In C. elegans, Livogrit prevented ROS generation, fat-6/7 gene overexpression, and lysosomal trapping of Amiodarone in N2 strain. SOD-3::GFP expression in CF1553 strain normalized by Livogrit treatment. Livogrit regulates phospholipidosis by regulation of redox homeostasis, phospholipid anabolism, and Pgp functionality hindered by lysosomal trapping of Amiodarone. Livogrit could be a potential therapeutic intervention for amelioration of drug-induced phospholipidosis and prevent hepatotoxicity.

Study on Protection of Human Umbilical Vein Endothelial Cells from Amiodarone-Induced Damage by Intermedin through Activation of Wnt/β-Catenin Signaling Pathway

Amiodarone (AM) is one of the most effective antiarrhythmic drugs and normally administrated by intravenous infusion which is liable to cause serious phlebitis. The therapeutic drugs for preventing this complication are limited. Intermedin (IMD), a member of calcitonin family, has a broad spectrum of biological effects including anti-inflammatory effects, antioxidant activities, and antiapoptosis. But now, the protective effects of IMD against amiodarone-induced phlebitis and the underlying molecular mechanism are not well understood. In this study, the aim was to investigate the protective efficiency and potential mechanisms of IMD in amiodarone-induced phlebitis. The results of this study revealed that treatment with IMD obviously attenuated apoptosis and exfoliation of vascular endothelial cells and infiltration of inflammatory cells in the rabbit model of phlebitis induced by intravenous infusion of amiodarone compared with control. Further tests in vitro demonstrated that IMD lessened amiodarone-induced endothelial cell apoptosis, improved amiodarone-induced oxidative stress injury, reduced inflammatory reaction, and activated the Wnt/β-catenin signal pathway which was inhibited by amiodarone. And these effects could be reversed by Wnt/β-catenin inhibitor IWR-1-endo, and si-RNA knocked down the gene of Wnt pathway. These results suggested that IMD exerted the protective effects against amiodarone-induced endothelial injury via activating the Wnt/β-catenin pathway. Thus, IMD could be used as a potential agent for the treatment of phlebitis.

Activity of the antiarrhythmic drug amiodarone against Leishmania (L.) infantum: an in vitro and in vivo approach

Background

Considering the high toxicity and limited therapies available for treating visceral leishmaniasis (VL), the drug repositioning approach represents a faster way to deliver new therapies to the market.

Methods

In this study, we described for the first time the activity of a potent antiarrhythmic, amiodarone (AMD), against L. (L.) infantum and its in vitro and in vivo activity.

Results

The evaluation against promastigotes has shown that amiodarone presents leishmanicidal effect against the extracellular form, with an IC₅₀ value of 10 μM. The activity was even greater against amastigotes in comparison with promastigotes with an IC₅₀ value of 0.5 μM. The selectivity index in relation to the intracellular form demonstrated that the antiparasitic activity was approximately 56 times higher than its toxicity to mammalian cells. Investigation of the in vivo AMD activity in the L. infantum-infected hamster model showed that 51 days after the initial infection, amiodarone was unable to reduce the parasite burden in the spleen and liver when treated for 10 consecutive days, intraperitoneally, at 50 mg/kg/day, as determined by qPCR. Although not statistically significant, AMD was able to reduce the parasite burden by 20% in the liver when treated for 10 consecutive days, orally, at 100 mg/kg/day; no reduction in the spleen was found by qPCR.

Conclusions

Our findings may help further drug design studies seeking new AMD derivatives that may provide new candidates with an in vitro selectivity close to or even greater than that observed in the prototype delivering effectiveness in the experimental model of VL.

Influence of Amiodarone and Dronedarone on the Force-Interval Dependence of Rat Myocardium

The antiarrhythmic effect of amiodarone and its analogue dronedarone is caused by their direct actions on several cardiomyocyte sarcolemmal ion currents. However, whether their effects are related to intracellular calcium levels is not exactly known. Ca²⁺ cycling refers to the release and reuptake of intracellular Ca²⁺, which induces muscle contraction and relaxation and determines the force-interval dependence. This study aimed to evaluate the influence of amiodarone and dronedarone on the force-interval relationship. Materials and Results. The work was performed on the papillary muscles of the left ventricle of male Wistar rats. Muscle perfusion was performed at 36.5°C with oxygenated Krebs-Henseleit solution with baseline stimulation 0.5 Hz. The postrest test (4-60 s) and the extrasystolic exposure (0.2-1.5 s) were evaluated. Inotropic reaction to the test exposure was evaluated before and after muscle perfusion with solution containing amiodarone (10⁻⁶ M) or dronedarone (10⁻⁶ M) during 10 min. Amiodarone or dronedarone led to decrease of the amplitude of extrasystolic contractions of the papillary muscles. The amplitude of postextrasystolic contractions after short extrasystolic intervals on the background of the drugs was increased. Amiodarone and dronedarone led to increase of the amplitude of postrest contractions. Conclusions. Dronedarone reduces the excitability of cardiomyocyte sarcolemma to a greater extent than amiodarone. Amiodarone and dronedarone are able to increase postextrasystolic and postrest potentiation. The effect of amiodarone on postextrasystolic and postrest potentiation is more pronounced in comparison with dronedarone.

Amiodarone-Induced Liver Injury and Cirrhosis

We present a case report of an 80-year-old woman with volume overload thought initially to be secondary to heart failure, but determined to be amiodarone-induced acute and chronic liver injury leading to submassive necrosis and bridging fibrosis consistent with early cirrhosis. Her histopathology was uniquely absent of steatosis and phospholipidosis, which are commonly seen in AIC.