Phosphorylation status of matrix metalloproteinase 2 in myocardial ischaemia-reperfusion injury.

Objective: To investigate whether alterations in the phosphorylation status of matrix metalloproteinase 2 (MMP-2) in the heart may be protective in the setting of ischaemia-reperfusion (IR) injury.

Design: In-vitro heart function and biochemical research study.

Setting: University basic science laboratory.

Regulation of lysophosphatidate signaling by autotaxin and lipid phosphate phosphatases with respect to tumor progression, angiogenesis, metastasis and chemo-resistance.

Evidence from clinical, animal and cell culture studies demonstrates that increased autotaxin (ATX) expression is responsible for enhancing tumor progression, cell migration, metastases, angiogenesis and chemo-resistance. These effects depend mainly on the rapid formation of lysophosphatidate (LPA) by ATX. Circulating LPA has a half-life of about 3 min in mice and it is degraded by the ecto-activities of lipid phosphate phosphatases (LPPs).

Antioxidant treatment protects diabetic rats from cardiac dysfunction by preserving contractile protein targets of oxidative stress.

Background: Animal studies suggest that reactive oxygen species (ROS) play an important role in the development of diabetic cardiomyopathy.

Hypothesis: Matrix metalloproteinase-2 (MMP-2) is activated by ROS and contributes to the acute loss of myocardial contractile function by targeting and cleaving susceptible proteins including troponin I (TnI) and alpha-actinin.

Methods: Using the streptozotocin-induced diabetic rat model, we evaluated the effect of daily in vivo administration of sodium selenate (0.

Phosphatidate degradation: phosphatidate phosphatases (lipins) and lipid phosphate phosphatases.

Three lipid phosphate phosphatases (LPPs) regulate cell signaling by modifying the concentrations of a variety of lipid phosphates versus their dephosphorylated products. In particular, the LPPs are normally considered to regulate signaling by the phospholipase D (PLD) pathway by converting phosphatidate (PA) to diacylglycerol (DAG). LPP activities do modulate the accumulations of PA and DAG following PLD activation, but this could also involve an effect upstream of PLD activation.

The PPARgamma agonist rosiglitazone enhances rat brown adipose tissue lipogenesis from glucose without altering glucose uptake.

We investigated the mechanisms whereby peroxisome proliferator-activated receptor-gamma (PPARgamma) agonism affects glucose and lipid metabolism in brown adipose tissue (BAT) by studying the impact of PPARgamma activation on BAT glucose uptake and metabolism, lipogenesis, and mRNA levels plus activities of enzymes involved in triacylglycerol (TAG) synthesis. Interscapular BAT of rats treated or not with rosiglitazone (15 mg*kg(-1).day(-1), 7 days) was evaluated in vivo for glucose uptake and lipogenesis and in vitro for glucose metabolism, gene expression, and activities of glycerolphosphate acyltransferase (GPAT), phosphatidate phosphatase-1 (PAP or lipin-1), and diacylglycerol acyltransferase (DGAT).