Toxicity and metabolism of 3-bromopyruvate in Caenorhabditis elegans

J Zhejiang Univ Sci B. 2020;21(1):77-86. doi: 10.1631/jzus.B1900370.

Abstract

In this study, we aimed to evaluate the toxic effects, changes in life span, and expression of various metabolism-related genes in Caenorhabditis elegans, using RNA interference (RNAi) and mutant strains, after 3-bromopyruvate (3-BrPA) treatment. C. elegans was treated with various concentrations of 3-BrPA on nematode growth medium (NGM) plates, and their survival was monitored every 24 h. The expression of genes related to metabolism was measured by the real-time fluorescent quantitative polymerase chain reaction (qPCR). Nematode survival in the presence of 3-BrPA was also studied after silencing three hexokinase (HK) genes. The average life span of C. elegans cultured on NGM with 3-BrPA was shortened to 5.7 d compared with 7.7 d in the control group. hxk-1, hxk-2, and hxk-3 were overexpressed after the treatment with 3-BrPA. After successfully interfering hxk-1, hxk-2, and hxk-3, the 50% lethal concentration (LC50) of all mutant nematodes decreased with 3-BrPA treatment for 24 h compared with that of the control. All the cyp35 genes tested were overexpressed, except cyp-35B3. The induction of cyp-35A1 expression was most obvious. The LC50 values of the mutant strains cyp-35A1, cyp-35A2, cyp-35A4, cyp-35B3, and cyp-35C1 were lower than that of the control. Thus, the toxicity of 3-BrPA is closely related to its effect on hexokinase metabolism in nematodes, and the cyp-35 family plays a key role in the metabolism of 3-BrPA.

Keywords: 3-Bromopyruvate; Caenorhabditis elegans; Hexokinase; Cytochrome P450.

MeSH terms

  • Animals
  • Caenorhabditis elegans / drug effects*
  • Caenorhabditis elegans / metabolism
  • Caenorhabditis elegans Proteins / genetics
  • Cytochrome P-450 Enzyme System / genetics
  • Hexokinase / genetics
  • Hexokinase / physiology
  • Pyruvates / metabolism
  • Pyruvates / toxicity*
  • RNA, Messenger / analysis

Substances

  • CYP35 protein, C elegans
  • Caenorhabditis elegans Proteins
  • Pyruvates
  • RNA, Messenger
  • bromopyruvate
  • Cytochrome P-450 Enzyme System
  • Hexokinase