Novel Role for Matrix Metalloproteinase 9 in Modulation of Cholesterol Metabolism.

Background: The development of atherosclerosis is strongly linked to disorders of cholesterol metabolism. Matrix metalloproteinases (MMPs) are dysregulated in patients and animal models with atherosclerosis. Whether systemic MMP activity influences cholesterol metabolism is unknown.

ADAMTS13 deficiency promotes microthrombosis in a murine model of diet-induced liver steatosis.

ADAMTS13 cleaves ultralarge multimeric von Willebrand Factor (VWF), thereby preventing formation of platelet-rich microthrombi. ADAMTS13 is mainly produced by hepatic stellate cells, and numerous studies have suggested a functional role of ADAMTS13 in the pathogenesis of liver diseases. The aim of our study was to investigate a potential role of ADAMTS13 in formation of hepatic microthrombi and development of non-alcoholic steatohepatitis (NASH), and furthermore to evaluate whether plasmin can compensate for the absence of ADAMTS13 in removal of thrombi.

Bacterial pathogens activate plasminogen to breach tissue barriers and escape from innate immunity.

Both coagulation and fibrinolysis are tightly connected with the innate immune system. Infection and inflammation cause profound alterations in the otherwise well-controlled balance between coagulation and fibrinolysis. Many pathogenic bacteria directly exploit the host's hemostatic system to increase their virulence.

Plasminogen activation by staphylokinase enhances local spreading of S. aureus in skin infections.

Background: Staphylococcus aureus (S. aureus) is a frequent cause of skin and soft tissue infections. A unique feature of S.

Tissue-type plasminogen activator is an extracellular mediator of Purkinje cell damage and altered gait.

Purkinje neurons are a sensitive and specialised cell type important for fine motor movement and coordination. Purkinje cell damage manifests as motor incoordination and ataxia - a prominent feature of many human disorders including spinocerebellar ataxia and Huntington's disease. A correlation between Purkinje degeneration and excess cerebellar levels of tissue-type plasminogen activator (tPA) has been observed in multiple genetically-distinct models of ataxia.

Differential effects of a gelatinase inhibitor on adipocyte differentiation and adipose tissue development.

(1) A potential role for the gelatinases in adipocyte differentiation in vitro and adipose tissue development in vivo was investigated using the gelatinase inhibitor tolylsam ((R)-3-methyl-2-[4-(3-p-tolyl-[1,2,4]oxadiazol-5-yl)-benzenesulphonylamino]-butyric acid). (2) Differentiation of murine 3T3-F442A preadipocytes (12 days after reaching confluence) into mature adipocytes in vitro was promoted in the presence of tolylsam (10-100 μmol/L). (3) De novo development of fat tissue in nude mice injected with preadipocytes and kept on a high-fat diet was significantly impaired following treatment with tolylsam (100 mg/kg per day for 4 weeks).

Host-derived plasminogen activator inhibitor-1 (PAI-1) concentration is critical for in vivo tumoral angiogenesis and growth.

Plasminogen activator inhibitor type 1 (PAI-1) plays a key role in tumor progression and is believed to control proteolytic activity and cell migration during angiogenesis. We report here that host PAI-1, at physiological concentration, promotes in vivo tumor invasion and angiogenesis. In sharp contrast, inhibition of tumor vascularization was observed when PAI-1 was produced at supraphysiologic levels, either by host cells (transgenic mice overexpressing PAI-1) or by tumor cells (after transfection with murine PAI-1 cDNA).