Gender-specific metabolic responses in hepatopancreas of mussel Mytilus galloprovincialis challenged by Vibrio harveyi

Mussel Mytilus galloprovincialis is a marine aquaculture shellfish and frequently studied in shellfish immunology. In this work, the gender-specific metabolic responses induced by Vibrio harveyi in hepatopancreas from M. galloprovincialis were characterized using NMR-based metabolomics. In details, V harveyi challenge increased the levels of amino acids including (valine, leucine, isoleucine, threonine, alanine, arginine and tyrosine) and ATP, and decreased the level of glucose in male mussel hepatopancreas. In V harveyi-challenged female mussel hepatopancreas, both threonine and AMP were significantly elevated, and choline, phoshphocholine, sn-glycero-3-phosphocholine, taurine, betaine and ATP were depleted. Obviously, only threonine was similarly altered to that in V harveyi-challenged male mussel hepatopancreas. These findings confirmed the gender-specific metabolic responses in mussels challenged by V. harveyi. Overall, V harveyi induced an enhanced energy demand through activated glycolysis and immune response indicated by increased BCAAs in male mussel hepatopancreas. In female mussel hepatopancreas, V harveyi basically caused disturbances in both osmotic regulation and energy metabolism through the metabolic pathways of conversions of phosphocholine and ADP to choline and ATP, and sn-glycero-3-phosphocholine and H2O into choline and sn-glycerol 3-phosphate. The altered mRNA expression levels of related genes (Cu/Zn-SOD, HSP90, lysozyme and defensin) suggested that V harveyi induced obvious oxidative and immune stresses in both male and female mussel hepatopancreas. This work demonstrated that V harveyi could induce gender-specific metabolic responses in mussel M. galloprovincialis hepatopancreas using NMR-based metabolomics. (C) 2014 Elsevier Ltd. All rights reserved.