The cardiomyopathy of the Syrian hamster (strain BIO 8262)--hypertrophic or dystrophic?

Endogenous murine microbiota member Faecalibaculum rodentium and its human homologue protect from intestinal tumour growth

The microbiota has been shown to promote intestinal tumourigenesis, but a possible anti-tumourigenic effect has also been postulated. Here, we demonstrate that changes in the microbiota and mucus composition are concomitant with tumourigenesis. We identified two anti-tumourigenic strains of the microbiota-Faecalibaculum rodentium and its human homologue, Holdemanella biformis-that are strongly under-represented during tumourigenesis. Reconstitution of ApcMin/+ or azoxymethane- and dextran sulfate sodium-treated mice with an isolate of F. rodentium (F. PB1) or its metabolic products reduced tumour growth. Both F. PB1 and H. biformis produced short-chain fatty acids that contributed to control protein acetylation and tumour cell proliferation by inhibiting calcineurin and NFATc3 activation in mouse and human settings. We have thus identified endogenous anti-tumourigenic bacterial strains with strong diagnostic, therapeutic and translational potential.

Altered distribution of myosin isoenzymes in the cardiomyopathic Syrian hamster (BIO 8.262)

Myosin of the ventricular myocardium of the cardiomyopathic Syrian hamster and of control animals was analysed using non-dissociating pyrophosphate electrophoresis. Three different myosin isoenzymes exhibiting different Ca2+ activated ATPase activities were demonstrated in the ventricular myocardium of the Syrian hamster. As shown by peptide mapping, ventricular myosin isoenzymes differ in their heavy chain composition. In the cardiomyopathic hamster a shift to myosins of lower Ca2+-activated ATPase activities occurs in the stage of insufficiency (age 220 days), whereas no different isoenzyme pattern could be found at the age of 65 days compared to control animals. We conclude that this redistribution of myosin isoenzymes is the basis of reduced myosin ATPase activity in the ventricular myocardium of the cardiomyopathic Syrian hamster during the development of myocardial insufficiency.