Although macrophages are widely recognized to have a profibrotic role in inflammation, we have used a highly tractable CCl 4 -induced model of reversible hepatic fibrosis to identify and characterize the macrophage phenotype responsible for tissue remodeling: the hitherto elusive restorative macrophage. This CD11B hi F4/80 int Ly-6C lo macrophage subset was most abundant in livers during maximal fibrosis resolution and represented the principle matrix metalloproteinase (MMP) -expressing subset. Depletion of this population in CD11B promoter-diphtheria toxin receptor (CD11B-DTR) transgenic mice caused a failure of scar remodeling. Adoptive transfer and in situ labeling experiments showed that these restorative macrophages derive from recruited Ly-6C hi monocytes, a common origin with profibrotic Ly-6C hi macrophages, indicative of a phenotypic switch in vivo conferring proresolution properties. Microarray profiling of the Ly-6C lo subset, compared with Ly-6C hi macrophages, showed a phenotype outside the M1/M2 classification, with increased expression of MMPs, growth factors, and phagocytosis-related genes, including Mmp9, Mmp12, insulin-like growth factor 1 (Igf1), and Glycoprotein (transmembrane) nmb (Gpnmb). Confocal microscopy confirmed the postphagocytic nature of restorative macrophages. Furthermore, the restorative macrophage phenotype was recapitulated in vitro by the phagocytosis of cellular debris with associated activation of the ERK signaling cascade. Critically, induced phagocytic behavior in vivo, through administration of liposomes, increased restorative macrophage number and accelerated fibrosis resolution, offering a therapeutic strategy to this orphan pathological process.

The GRACE risk score predicts early and 5 year death and CVD/MI. Five year morbidity and mortality are as high in patients following non-ST MI and UA as seen following STEMI. Their morbidity burden is high (MI, stroke, readmissions) and the substantial late mortality in non-STE ACS is under-recognized. The findings highlight the importance of pursuing novel approaches to diminish long-term risk.

The IUPHAR database (IUPHAR-DB) integrates peer-reviewed pharmacological, chemical, genetic, functional and anatomical information on the 354 nonsensory G protein-coupled receptors (GPCRs), 71 ligand-gated ion channel subunits and 141 voltage-gated-like ion channel subunits encoded by the human, rat and mouse genomes. These genes represent the targets of approximately one-third of currently approved drugs and are a major focus of drug discovery and development programs in the pharmaceutical industry. IUPHAR-DB provides a comprehensive description of the genes and their functions, with information on protein structure and interactions, ligands, expression patterns, signaling mechanisms, functional assays and biologically important receptor variants (e.g. single nucleotide polymorphisms and splice variants). In addition, the phenotypes resulting from altered gene expression (e.g. in genetically altered animals or in human genetic disorders) are described. The content of the database is peer reviewed by members of the International Union of Basic and Clinical Pharmacology Committee on Receptor Nomenclature and Drug Classification (NC-IUPHAR); the data are provided through manual curation of the primary literature by a network of over 60 subcommittees of NC-IUPHAR. Links to other bioinformatics resources, such as NCBI, Uniprot, HGNC and the rat and mouse genome databases are provided. IUPHAR-DB is freely available at http://www.iuphar-db.org.

SummaryBackgroundCells undergoing apoptosis are known to modulate their tissue microenvironments. By acting on phagocytes, notably macrophages, apoptotic cells inhibit immunological and inflammatory responses and promote trophic signaling pathways. Paradoxically, because of their potential to cause death of tumor cells and thereby militate against malignant disease progression, both apoptosis and tumor-associated macrophages (TAMs) are often associated with poor prognosis in cancer. We hypothesized that, in progression of malignant disease, constitutive loss of a fraction of the tumor cell population through apoptosis could yield tumor-promoting effects.ResultsHere, we demonstrate that apoptotic tumor cells promote coordinated tumor growth, angiogenesis, and accumulation of TAMs in aggressive B cell lymphomas. Through unbiased “in situ transcriptomics” analysis—gene expression profiling of laser-captured TAMs to establish their activation signature in situ—we show that these cells are activated to signal via multiple tumor-promoting reparatory, trophic, angiogenic, tissue remodeling, and anti-inflammatory pathways. Our results also suggest that apoptotic lymphoma cells help drive this signature. Furthermore, we demonstrate that, upon induction of apoptosis, lymphoma cells not only activate expression of the tumor-promoting matrix metalloproteinases MMP2 and MMP12 in macrophages but also express and process these MMPs directly. Finally, using a model of malignant melanoma, we show that the oncogenic potential of apoptotic tumor cells extends beyond lymphoma.ConclusionsIn addition to its profound tumor-suppressive role, apoptosis can potentiate cancer progression. These results have important implications for understanding the fundamental biology of cell death, its roles in malignant disease, and the broader consequences of apoptosis-inducing anti-cancer therapy.

Glucocorticoid levels rise dramatically in late gestation to mature foetal organs in readiness for postnatal life. Immature heart function may compromise survival. Cardiomyocyte glucocorticoid receptor (GR) is required for the structural and functional maturation of the foetal heart in vivo, yet the molecular mechanisms are largely unknown. Here we asked if GR activation in foetal cardiomyocytes in vitro elicits similar maturational changes. We show that physiologically relevant glucocorticoid levels improve contractility of primary-mouse-foetal cardiomyocytes, promote Z-disc assembly and the appearance of mature myofibrils, and increase mitochondrial activity. Genes induced in vitro mimic those induced in vivo and include PGC-1α, a critical regulator of cardiac mitochondrial capacity. SiRNA-mediated abrogation of the glucocorticoid induction of PGC-1α in vitro abolished the effect of glucocorticoid on myofibril structure and mitochondrial oxygen consumption. Using RNA sequencing we identified a number of transcriptional regulators, including PGC-1α, induced as primary targets of GR in foetal cardiomyocytes. These data demonstrate that PGC-1α is a key mediator of glucocorticoid-induced maturation of foetal cardiomyocyte structure and identify other candidate transcriptional regulators that may play critical roles in the transition of the foetal to neonatal heart.

After the introduction of mitochondria with a mixture of mutant and wild-type mitochondrial DNA (mtDNA) into a human p0 cell line (143B.206), Yoneda et al. [Yoneda, M., Chomyn, A., Martinuzzi, A., Hurko, 0. & Attardi, G. (1992) Proc. Natl. Acad. Sci. USA 89, [11164][11165][11166][11167][11168] observed a shift in the proportion of the two mitochondrial genotypes in a number of cybrid clones. In every case where a shift was observed, there was an increase in the proportion of mutant mtDNA. By using the same cell line (143B.206 p°), we also generated cybrids that were either stable in their mitochondrial genotype or showed an increase in the proportion of mutant mtDNA. However, temporal analysis of the same mutant mtDNA type in another p0 cell line revealed a quite distinct outcome. Those clones that showed a change shifted toward higher levels of wild-type rather than mutant mtDNA. These results indicate that the nuclear genetic background of the recipient (p0) cell can influence the segregation of mutant and wild-type mitochondrial genomes in cell cybrids.Disease-associated mitochondrial DNA (mtDNA) mutations were first recognized in 1988 (1). These mutations were large deletions, accounting for 15-50% of the 16.6-kb genome. All the patients showed the proliferation of skeletal muscle mitochondria characteristic of mitochondrial myopathy (2), and in each case, the partially deleted genomes were found to coexist with apparently wild-type genomes. Subsequently, a number of disease-associated mtDNA point mutations were identified (3-6). One of these, an A -> G point mutation in the mitochondrial tRNALeU(UUR) gene at bp 3243, accounts for the majority of cases of MELAS syndrome (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) (6). As with partial deletions of mtDNA, wild-type mtDNA molecules coexisted with the mutant molecules.A human cell line devoid of endogenous mtDNA (p°) was generated in 1989 (7) and was used to provide evidence that mitochondrial genomes with the bp-3243 mutation caused respiratory deficiency (8, 9). Mitochondria from patients with MELAS were introduced into p0 cells and cybrid cell lines were established. Clonal cell lines with high levels of mutant mtDNA showed decreased in vitro mitochondrial translation products and whole-cell oxygen consumption.Yoneda et al. (10) have described clonal cybrid lines that were derived from the fusion of cytoplasts containing MELAS patient mitochondria with a recipient p0 cell line. Some of the resulting cybrids contained a mixture of mutant and wild-type mitochondrial genomes. Temporal analysis revealed that in 5 of 13 clones investigated, the proportion of mutant mtDNA increased with time. In no case was a shift toward wild-type mtDNA observed. In addition, the level of mutant mtDNA reached 95% in only one cybrid line, and in this case, respi-The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734...

Dendritic cells (DCs) have a central role in the development of adaptive immune responses, including antitumor immunity. Factors present in the tumor milieu can alter the maturation of DCs and inhibit their capacity to activate T cells. Using gene expression analysis, we found that human DCs increased the expression of TGF-β1 transcripts following culture with human lung carcinoma cells (LCCs). These DCs produced increased amounts of TGF-β1 protein compared with DCs not exposed to tumor cells. LCCs also decreased the expression of CD86 and HLA-DR by immature DCs. Furthermore, LCCs decreased CD86 expression and the production of TNF-α and IL-12 p70 by mature DCs. Moreover, LCCs also converted mature DCs into cells producing TGF-β1. These TGF-β1-producing DCs were poor at eliciting the activation of naive CD4+ T cells and sustaining their proliferation and differentiation into Th1 (IFN-γ+) effectors. Instead, TGF-β1-producing DCs demonstrated an increased ability to generate CD4+CD25+Foxp3+ regulatory T cells that suppress the proliferation of T lymphocytes. These results identify a novel mechanism by which the function of human DCs is altered by tumor cells and contributes to the evasion of the immune response.

GPR50 is an orphan G protein-coupled receptor (GPCR) located on Xq28, a region previously implicated in multiple genetic studies of bipolar affective disorder (BPAD). Allele frequencies of three polymorphisms in GPR50 were compared in case-control studies between subjects with BPAD (264), major depressive disorder (MDD) (226), or schizophrenia (SCZ) (263) and ethnically matched controls (562). Significant associations were found between an insertion/ deletion polymorphism in exon 2 and both BPAD (P ¼ 0.0070), and MDD (P ¼ 0.011) with increased risk associated with the deletion variant (GPR50 D502-505 ). When the analysis was restricted to female subjects, the associations with BPAD and MDD increased in significance (P ¼ 0.00023 and P ¼ 0.0064, respectively). Two other single-nucleotide polymorphisms (SNPs) tested within this gene showed associations between: the female MDD group and an SNP in exon 2 (P ¼ 0.0096); and female SCZ and an intronic SNP (P ¼ 0.0014). No association was detected in males with either MDD, BPAD or SCZ. These results suggest that GPR50 D502-505 , or a variant in tight linkage disequilibrium with this polymorphism, is a sex-specific risk factor for susceptibility to bipolar disorder, and that other variants in the gene may be sex-specific risk factors in the development of schizophrenia. Bipolar affective disorder (BPAD) is a severe psychiatric disorder affecting approximately 1% of the world's population, and shows no difference in lifetime prevalence between male and female subjects. Twin and adoption studies have demonstrated a strong genetic component, with a concordance in BPAD between monozygotic twins of 60%. 1 Major depressive disorder (MDD) has a lifetime prevalence of 17% with women twice as likely as men to develop the disorder. 2 Estimates of the heritability of MDD vary, but a meta-analysis of studies gives a point estimate of heritability of liability to MDD of 0.37. 3 Schizophrenia (SCZ), as with BPAD, has an estimated frequency of 1% in the population, but heritability estimates suggest that it has a larger genetic component than either BPAD or MDD, with monozygotic twins giving a point estimate of comorbidity of 0.81 in another recent meta-analysis. 4 Despite the strong genetic component in these major psychiatric disorders, there are also strong environmental influences.Linkage to Xq28 has been studied many times in BPAD. Two loci, colour-blindness (CB), and glucose-6-phosphate dehydrogenase (G6PD), have been detected through linkage and association in more than one population. 5 Most significant are LOD scores of 8.1 and 7.35 between CB and BPAD in the American and Belgian populations, respectively, although reanalysis of much of the data from positive linkage results on the X chromosome has resulted in much reduced evidence for linkage and suggestions of ascertainment bias. 6-9 Several more recent studies have again renewed interest in the distal end of Xq, although the region implicated in these studies (Xq24-28) is larger than that depicted in the earlier reports. 5,[...