Molecular MR Imaging of Myeloperoxidase Distinguishes Steatosis from Steatohepatitis in Nonalcoholic Fatty Liver Disease.

Purpose To test whether MPO-Gd, an activatable molecular magnetic resonance (MR) imaging agent specific for myeloperoxidase (MPO) activity, could detect MPO activity in nonalcoholic steatohepatitis (NASH) mouse models and human liver biopsy samples. Materials and Methods In this study, 20 leptin receptor-deficient and three MPO knockout mice were injected with endotoxin (lipopolysaccharide) or fed a methionine and choline-deficient (MCD) diet to induce experimental NASH and underwent MR imaging with MPO-Gd. Saline-injected and control diet-fed leptin receptor-deficient mice were used as respective controls.

In vivo nanoparticle imaging of innate immune cells can serve as a marker of disease severity in a model of multiple sclerosis.

Innate immune cells play a key role in the pathogenesis of multiple sclerosis and experimental autoimmune encephalomyelitis (EAE). Current clinical imaging is restricted to visualizing secondary effects of inflammation, such as gliosis and blood-brain barrier disruption. Advanced molecular imaging, such as iron oxide nanoparticle imaging, can allow direct imaging of cellular and molecular activity, but the exact cell types that phagocytose nanoparticles in vivo and how phagocytic activity relates to disease severity is not well understood.

Gelsolin decreases actin toxicity and inflammation in murine multiple sclerosis.

Gelsolin is the fourth most abundant protein in the body and its depletion in the blood has been found in multiple sclerosis (MS) patients. How gelsolin affects the MS brain has not been studied. We found that while the secreted form of gelsolin (pGSN) decreased in the blood of experimental autoimmune encephalomyelitis (EAE) mice, pGSN concentration increased in the EAE brain.

Myeloperoxidase-Hepatocyte-Stellate Cell Cross Talk Promotes Hepatocyte Injury and Fibrosis in Experimental Nonalcoholic Steatohepatitis.

Aims: Myeloperoxidase (MPO), a highly oxidative enzyme secreted by leukocytes has been implicated in human and experimental nonalcoholic steatohepatitis (NASH), but the underlying mechanisms remain unknown. In this study, we investigated how MPO contributes to progression from steatosis to NASH.

Results: In C57Bl/6J mice fed a diet deficient in methionine and choline to induce NASH, neutrophils and to a lesser extent inflammatory monocytes are markedly increased compared with sham mice and secrete abundant amounts of MPO.