{"title":"Metronidazole induces prostaglandin E2 formation via arachidonic acid production in protozoan parasite Giardia lamblia","authors":"Rituparna Sarkar , Sanjib Kumar Sardar , Ajanta Ghosal , Tapas Haldar , Koushik Das , Arjun Ghosh , Akash Prasad , Yumiko Saito-Nakano , Shanta Dutta , Tomoyoshi Nozaki , Sandipan Ganguly","doi":"10.1016/j.molbiopara.2025.111676","DOIUrl":null,"url":null,"abstract":"<div><div>The causative agent of giardiasis in human and animals is the amitochondriate <em>Giardia lamblia.</em> We observed that exposing <em>Giardia</em> trophozoites to MTZ led to an increase in lipid peroxidation compared to the control group, which was expressed in terms of menadione production as it is the marker for lipo-peroxidation. Oxidative stress generated by reactive nitrogen species and peroxidation of membrane phospholipids are positively correlated with the enhanced PLA2 activity in several organisms to produce arachidonic acid (AA). Our data suggested <em>Giardia</em> produces a unique 56 kDa dimeric enzyme called Phospholipase B (gPLB) in contrast to higher eukaryotes which was responsible for the production of intracellular free AA. This free AA either reacylates to the cell membrane or deacylates to further produce prostaglandins. In normal un-induced controlled trophozoites the membrane reacylation process was dominant due the higher level of acyle CoA synthase (ACS) expression over the time. However, under the oxidative stressed condition the intracellular ACS expression was down regulated. This led to the increase in deacylation process. When AA deacylation becomes dominant over AA reacylation in cells, the free AA accumulates intracellularly. One of the lipid autacoids, derived from AA is prostaglandin2 (PGE2). Oxidative stress generated by reactive nitrogen species in trophozoites increased the PGE2 production via prostaglandin synthase over the time with respect to the controlled one.</div></div>","PeriodicalId":18721,"journal":{"name":"Molecular and biochemical parasitology","volume":"262 ","pages":"Article 111676"},"PeriodicalIF":1.4000,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecular and biochemical parasitology","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S016668512500012X","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The causative agent of giardiasis in human and animals is the amitochondriate Giardia lamblia. We observed that exposing Giardia trophozoites to MTZ led to an increase in lipid peroxidation compared to the control group, which was expressed in terms of menadione production as it is the marker for lipo-peroxidation. Oxidative stress generated by reactive nitrogen species and peroxidation of membrane phospholipids are positively correlated with the enhanced PLA2 activity in several organisms to produce arachidonic acid (AA). Our data suggested Giardia produces a unique 56 kDa dimeric enzyme called Phospholipase B (gPLB) in contrast to higher eukaryotes which was responsible for the production of intracellular free AA. This free AA either reacylates to the cell membrane or deacylates to further produce prostaglandins. In normal un-induced controlled trophozoites the membrane reacylation process was dominant due the higher level of acyle CoA synthase (ACS) expression over the time. However, under the oxidative stressed condition the intracellular ACS expression was down regulated. This led to the increase in deacylation process. When AA deacylation becomes dominant over AA reacylation in cells, the free AA accumulates intracellularly. One of the lipid autacoids, derived from AA is prostaglandin2 (PGE2). Oxidative stress generated by reactive nitrogen species in trophozoites increased the PGE2 production via prostaglandin synthase over the time with respect to the controlled one.
期刊介绍:
The journal provides a medium for rapid publication of investigations of the molecular biology and biochemistry of parasitic protozoa and helminths and their interactions with both the definitive and intermediate host. The main subject areas covered are:
• the structure, biosynthesis, degradation, properties and function of DNA, RNA, proteins, lipids, carbohydrates and small molecular-weight substances
• intermediary metabolism and bioenergetics
• drug target characterization and the mode of action of antiparasitic drugs
• molecular and biochemical aspects of membrane structure and function
• host-parasite relationships that focus on the parasite, particularly as related to specific parasite molecules.
• analysis of genes and genome structure, function and expression
• analysis of variation in parasite populations relevant to genetic exchange, pathogenesis, drug and vaccine target characterization, and drug resistance.
• parasite protein trafficking, organelle biogenesis, and cellular structure especially with reference to the roles of specific molecules
• parasite programmed cell death, development, and cell division at the molecular level.