larvi 2013
ghent university, belgium, 2-5 september 2013
6th fish & shellfish larviculture symposium
Lipid digestion in first feeding larvae -visualization in vivo
Øystein Saele
Lipid digestion in first feeding larvae,an in vivo study
Øystein Sæle, Kari Elin Rød & Steven Farber
How to study lipid digestion in a 4 mm fish larvae?
Homogenate of whole animal• Enzyme activity• Protein (western blot/ELISA)• Gene expression (qPCR)
Liver Brain Kidney Gill MuscleTissue
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
Act
ivity
n.d.
Sæle et al., 2011
Absorbed
Gut Retained
Evacuated
Catabolised (CO2)
4.5 mm SL
Ingested
Radiolabeled lipids
18:1 – C11TopFluo – C11TopFluo
Fluorescent lipids
0.06% 99.94%
Emulsions
Lipid digestion
BAL
HPLC fluorescent detector
Rinse Extract
Digested and re-synthesized
Undigested
Ingested
Absorbed
Gut
Retained
EvacuatedCatabolised (CO2)
Fluorecent lipids
Visualization
Orlistat TG
TG
Orlistat TG+PC
TG+PC
Quantification
Phospholipid digestion
Feeding trials
TG
PC
TG
PCTGPCTGPC
a a
ba
a a
b
a
Atlantic cod larvae
a
b c
d
TG
PC
TG
PCTGPCTGPC
Atlantic cod larvae
Chemicals that affect lipid digestionGenes that affect lipid digestionconclusionsWe have developed a tool for screening:
Conclusions
Chemicals that affect lipiddigestion
Genes that affect lipid digestion
How nutrient composition affectlipid metabolism
Thank youThis work has been financed by the Norwegian Research Council project: CODE.
We would like to thank Avanti Polar Lipids, Inc (USA) for donating the TopFluor lipids