INTEGRATED APPROACHES FOR IMPROVING THE EFFICIENCY AND SUSTAINABILITY OF MORONE AND OTHER WARM WATER FISH PRODUCTION
Location: Harry K. Dupree Stuttgart National Aquaculture Research Center
Title: Bioenergetic phenotypes and metabolic stress responses in cells derived from ecologically and commercially important fish species
Submitted to: Book of Abstracts Aquaculture America
Publication Type: Abstract Only
Publication Acceptance Date: November 10, 2011
Publication Date: February 29, 2012
Citation: Beck, B.H., Fuller, S.A. 2012. Bioenergetic phenotypes and metabolic stress responses in cells derived from ecologically and commercially important fish species [abstract]. Book of Abstracts Aquaculture America 2012: Bringing All Players to the Table. p.43.
As organisms intimately associated with their environment, fish are sensitive to numerous environmental insults which can negatively affect their cellular physiology. For our purposes, fish subject to intensive farming practices can experience a host of acute and chronic stressors such as changes in dissolved oxygen, temperature, and water quality; all of which can result in metabolic perturbations on a cellular level. Thus, in the present study, we sought to further our understanding of cellular metabolism in fish and to examine the stress response of cells derived from commercially relevant fish species (catfish, white bass, fathead minnow). We employed a Seahorse Bioscience XF24 Extracellular Flux (EF) Analyzer, an instrument which detects changes in oxygen (O2) levels and pH within the media directly surrounding cells. By measuring the O2 consumption rate (OCR), an indicator of mitochondrial respiration, we determined that all cells tested exhibited a markedly aerobic phenotype (OCR greater than 100 pMol/min). Simultaneously, we measured the extracellular acidification rate (ECAR), an indicator of glycolysis, and found that in all cell lines tested the ECAR was very low (less than 5 mpH/min). Next, we performed a mitochondrial function protocol whereby compounds modulating mitochondrial respiration were sequentially exposed to cells (oligomycin – FCCP - rotenone). For each cell type, this assay provided us with basal and maximal OCR, O2 consumption dedicated to ATP production, O2 consumption from ion movement across the mitochondrial inner membrane, the reserve respiratory capacity, and O2 consumption independent of Complex IV of the electron transport chain. From these informative bioenergetic parameters we generated distinct metabolic signatures for each cell type. These findings are the first description of EF technology employed on fish cell lines and provide key proof-of-concept data demonstrating the utility of fish cells as tools for modeling bioenergetics. We hope to extend these findings to develop assays predictive of how fish may cope with cellular insults encountered in production settings.