Methotrexate induced mitochondrial injury and cytochrome c release in rat liver hepatocytes

Abstract

Methotrexate (MTX) is a folic acid antagonist that is widely used to treat a variety of diseases. One of the most serious side effects of MTX therapy is hepatotoxicity. The potential molecular cytotoxic mechanisms of MTX toward isolated rat hepatocytes were investigated using Accelerated Cytotoxicity Mechanism Screening (ACMS) techniques. A concentration and time dependent increase in cytotoxicity and reactive oxygen species (ROS) formation and a decrease in mitochondrial membrane potential (MMP) were observed with MTX. Furthermore, a significant increase in MTX (300 μM)-induced cytotoxicity and ROS formation were observed when glutathione (GSH)-depleted hepatocytes were used whereas addition of N-acetylcysteine (a GSH precursor) decreased cytotoxicity. Catalase inactivation also increased MTX-induced cytotoxicity, while the direct addition of catalase to the hepatocytes decreased cytotoxicity. MTX treatment in isolated rat mitochondria caused swelling and significantly decreased adenosine triphosphate (ATP) and GSH content, and cytochrome c release. Potent antioxidants such as mesna, resveratrol and Trolox decreased MTX-induced cytotoxicity and ROS formation and increased MMP. This study suggests that MTX-induced cytotoxicity caused by ROS formation and GSH oxidation leads to oxidative stress and mitochondrial injury in rat hepatocytes.

Neuro Protective Effects of Wheat Germ Oil on the Brain Inflammation Induced by Methotrexate in Mice

“…A new study in Proceedings of the National Academy of Sciences USA indicates that two-thirds of the brain's energy is used to help neurons send signals and the remaining third is used for cell-health maintenance, most of this energy is attained from ATP molecules through mitochondrial oxidative phosphorylation. Thus, we conclude that the reduction in ATP production is due to the harmful effects of MTX on the mitochondria, this result was previously recorded by 66 who established that MTX treatment caused swelling in the mitochondria of rats and significantly decreased adenosine triphosphate (ATP).…”

Treatment of primary biliary cholangitis ursodeoxycholic acid non‐responders: A systematic review

“…Methotrexate is an anti‐metabolite that inhibits dihydrofolic acid reductase thereby inhibiting purine and thymotic acid synthesis . It is an immunosuppressive agent with anti‐inflammatory effects.…”

“…Methotrexate is an anti-metabolite that inhibits dihydrofolic acid reductase thereby inhibiting purine and thymotic acid synthesis. 30 It is an immunosuppressive agent with anti-inflammatory effects. One study looking at the benefit of adding methotrexate to UDCA found no differences in treatment failure between the methotrexate and placebo arm.…”

Nicotinamide Phosphoribosyltransferase Deficiency Potentiates the Antiproliferative Activity of Methotrexate through Enhanced Depletion of Intracellular ATP

“…1), and we therefore demonstrated that this interaction is broadly applicable to both transformed and primary tissues. Although MTX is widely believed to mediate its pharmacological activity through inhibition of folate-dependent biochemical pathways, either through the depletion of the intracellular pool of bioactive folates or through the direct inhibition of the various folate-dependent enzymes, some investigators have suggested folate-independent pharmacological effects of MTX mediated through inhibition of Janus kinase/signal transducers and activators of transcription signaling, induction of oxidative stress, and mitochondrial toxicity (Phillips et al, 2003;Thomas et al, 2015;Zimmerman et al, 2017;Al Maruf et al, 2018). Therefore, we evaluated whether supplementation with folinic acid would reverse the increased antiproliferative effects of MTX in NAMPT-deficient cells (Fig.…”