Caspian Sea gammarus (Pontogammarus maeoticus) as a carotenoid source for muscle pigmentation of rainbow trout (Oncorhynchus mykiss)

The red coloration of rainbow trout muscle is an important quality criterion. Duplicate groups of rainbow trout (Oncorhynchus mykiss; initial weight of 200±10g) were fed diets either supplemented 0 (control), 0.5, 2, or 4%, of the Caspian Sea gammarus (Pontogammarus maeoticus) respectively as a prospective alternative carotenoid source. The feeding trial lasted for 39 days. No significant differences (p>0.05) in specific growth rate (SGR), or condition factor (CF) were found between treatments. Carotenoid concentrations were determined in the dorsal region and the Norwegian Quality Cut (NQC). The correlation between mean total carotenoid content of the Norwegian quality cut per treatment and dietary inclusion level of P. maeoticus was high (R2=0.99; p<0.01). Less correlation was found between total carotenoid content of the dorsal cut and inclusion level of P. maeoticus (R2=0.80; P=0.10). The total carotenoid concentrations were significantly higher (p<0.05) in male (4.26±0.39 mg/kg) than in female (3.38±0.23 mg/kg) rainbow trout. In conclusion, it was found that dietary supplementation of the Caspian Sea gammarus at levels of 2 and 4% effectively improved muscle pigmentation of rainbow trout

Pathological relationships involving iron and myelin may constitute a shared mechanism linking various rare and common brain diseases.

We previously demonstrated elevated brain iron levels in myelinated structures and associated cells in a hemochromatosis Hfe (-/-) xTfr2 (mut) mouse model. This was accompanied by altered expression of a group of myelin-related genes, including a suite of genes causatively linked to the rare disease family 'neurodegeneration with brain iron accumulation' (NBIA). Expanded data mining and ontological analyses have now identified additional myelin-related transcriptome changes in response to brain iron loading. Concordance between the mouse transcriptome changes and human myelin-related gene expression networks in normal and NBIA basal ganglia testifies to potential clinical relevance. These analyses implicate, among others, genes linked to various rare central hypomyelinating leukodystrophies and peripheral neuropathies including Pelizaeus-Merzbacher-like disease and Charcot-Marie-Tooth disease as well as genes linked to other rare neurological diseases such as Niemann-Pick disease. The findings may help understand interrelationships of iron and myelin in more common conditions such as hemochromatosis, multiple sclerosis and various psychiatric disorders