A transgenic mouse model for the in vivo bioluminescence imaging of the expression of the lysophosphatidic acid receptor 3: relevance for inflammation and uterine physiology research.

Lysophosphatidic acid (LPA) is a lipid-derived signaling molecule that plays key roles in diverse biological processes including inflammation and uterine remodeling. Although the function of LPA and its receptors has been extensively studied using knock-out mice, the temporal-spatial expression of LPA receptors is less well-characterized. To gain further insight into the dynamic regulation of LPA receptor 3 (Lpar3) expression in vivo by bioluminescence imaging, we generated and characterized mice transgenic for a putative Lpar3 promoter fragment.

A gut-brain neural circuit controlled by intestinal gluconeogenesis is crucial in metabolic health.

Objectives: Certain nutrients positively regulate energy homeostasis via intestinal gluconeogenesis (IGN). The objective of this study was to evaluate the impact of a deficient IGN in glucose control independently of nutritional environment.

Methods: We used mice deficient in the intestine glucose-6 phosphatase catalytic unit, the key enzyme of IGN (I-G6pc (-/-) mice).

A link between hepatic glucose production and peripheral energy metabolism via hepatokines.

Type 2 diabetes is characterized by a deterioration of glucose tolerance, which associates insulin resistance of glucose uptake by peripheral tissues and increased endogenous glucose production. Here we report that the specific suppression of hepatic glucose production positively modulates whole-body glucose and energy metabolism. We used mice deficient in liver glucose-6 phosphatase that is mandatory for endogenous glucose production.

TNF-alpha promotes LPA1- and LPA3-mediated recruitment of leukocytes in vivo through CXCR2 ligand chemokines.

Lysophosphatidic acid (LPA) is a bioactive lysophospholipid present in low concentrations in serum and biological fluids but in high concentrations at sites of inflammation. LPA evokes a variety of cellular responses via binding to and activation of its specific G protein-coupled receptors (GPCR), namely LPA(1-6). Even though LPA is a chemoattractant for inflammatory cells in vitro, such a role for LPA in vivo remains largely unexplored.