Neutrophils are key effector cells of the innate immune response and are required to migrate and function within adverse microenvironmental conditions. These inflammatory sites are characterized by low levels of oxygen and glucose and high levels of reductive metabolites. A major regulator of neutrophil functional longevity is the ability of these cells to undergo apoptosis. We examined the mechanism by which hypoxia causes an inhibition of neutrophil apoptosis in human and murine neutrophils. We show that neutrophils possess the hypoxia-inducible factor (HIF)-1α and factor inhibiting HIF (FIH) hydroxylase oxygen-sensing pathway and using HIF-1α–deficient myeloid cells demonstrate that HIF-1α is directly involved in regulating neutrophil survival in hypoxia. Gene array, TaqMan PCR, Western blotting, and oligonucleotide binding assays identify NF-κB as a novel hypoxia-regulated and HIF-dependent target, with inhibition of NF-κB by gliotoxin or parthenolide resulting in the abrogation of hypoxic survival. In addition, we identify macrophage inflammatory protein-1β as a novel hypoxia-induced neutrophil survival factor.

Obesity is highly prevalent, and its incidence is increasing. The previous study showing a major effect of paternal obesity on metabolic health of offspring is confounded by comorbidity with diabetes. Therefore, we investigated the effect of diet‐induced paternal obesity, in the absence of diabetes, on the metabolic health of two resultant generations and the molecular profiles of the testes and sperm. Founder (F ₀ ) male C57BL6 mice were fed either a high‐fat diet (HFD) or a control diet (CD); n = 10/diet for a period of 10 wk. Testis expression of mRNA/microRNAs was analyzed by microarray and qPCR and sperm microRNA abundance by qPCR Two subsequent generations were generated by mating F ₀ and then F ₁ mice to CD mice, and their metabolic health was investigated. All mice, other than F ₀ males, were maintained on a CD. HFD feeding induced paternal obesity with a 21% increase in adiposity, but not overt diabetes, and initiated intergenerational transmission of obesity and insulin resistance in two generations of offspring. This distinct phenotypic constellation is either partially or fully transmitted to both female and male F ₁ offspring and further transmitted through both parental lineages to the F ₂ generation, with a heightened effect on female F ₁ offspring (+67% in adiposity) and their F ₂ sons (+24% in adiposity). Founder male obesity altered the testes expression of 414 mRNAs by microarray and 11 microRNAs by qPCR, concomitant with alterations in sperm microRNA content and a 25% reduction in global methylation of germ cell DNA Diet‐induced paternal obesity modulates sperm microRNA content and germ cell methylation status, which are potential signals that program offspring health and initiate the transmission of obesity and impaired metabolic health to future generations. This study implicates paternal obesity in the transgenerational amplification of obesity and type 2 diabetes in humans.—Fullston, T., Ohlsson Teague, E. M. C., Palmer, N. O., DeBlasio, M. J., Mitchell, M., Corbett, M., Print, C. G., Owens, J. A., Lane, M., Paternal obesity initiates metabolic disturbances in two generations of mice with incomplete penetrance to the F2 generation and alters the transcriptional profile of testis and sperm microRNA content. FASEBJ. 27, 4226‐4243 (2013). www.fasebj.org

Endometriosis is a prevalent gynecological disease characterized by growth of endometriotic tissue outside the uterine cavity. MicroRNAs (miRNAs) are naturally occurring posttranscriptional regulatory molecules that potentially play a role in endometriotic lesion development. We assessed miRNA expression by microarray analysis in paired ectopic and eutopic endometrial tissues and identified 14 up-regulated (miR-145, miR-143, miR-99a, miR-99b, miR-126, miR-100, miR-125b, miR-150, miR-125a, miR-223, miR-194, miR-365, miR-29c and miR-1) and eight down-regulated (miR-200a, miR-141, miR-200b, miR-142-3p, miR-424, miR-34c, miR-20a and miR-196b) miRNAs. The differential expression of six miRNAs was confirmed by quantitative RT-PCR. An in silico analysis identified 3851 mRNA transcripts as putative targets of the 22 miRNAs. Of these predicted targets, 673 were also differentially expressed in ectopic vs. eutopic endometrial tissue, as determined by microarray. Functional analysis suggested that the 673 miRNA targets constitute molecular pathways previously associated with endometriosis, including c-Jun, CREB-binding protein, protein kinase B (Akt), and cyclin D1 (CCND1) signaling. These pathways appeared to be regulated both transcriptionally as well as by miRNAs at posttranscriptional level. These data are a rich and novel resource for endometriosis and miRNA research and suggest that the 22 miRNAs and their cognate mRNA target sequences constitute pathways that promote endometriosis. Accordingly, miRNAs are potential therapeutic targets for treating this disease.

Bcl-2, which can both reduce apoptosis and retard cell cycle entry, is thought to have important roles in hematopoiesis. To evaluate the impact of its ubiquitous overexpression within this system, we targeted expression of the human bcl-2 gene in mice by using the promoter of the vav gene, which is active throughout this compartment but rarely outside it. The vav-bcl-2 transgene was expressed in essentially all nucleated cells of hematopoietic tissues but not notably in nonhematopoietic tissues. Presumably because of enhanced cell survival, the mice displayed increases in myeloid cells as well as a marked elevation in B and T lymphocytes. The spleen was enlarged and the lymphoid follicles expanded. Although total thymic cellularity was normal, T cell development was altered: cells at the very immature and most mature stages were increased, whereas those at the intermediate stage were decreased. Unexpectedly, blood platelets were reduced by half, suggesting that their production from megakaryocytes is regulated by the Bcl-2 family. Colony formation by myeloid progenitor cells in vitro remained cytokine dependent, and the frequency of most progenitor and preprogenitor cells was normal. Macrophage progenitors were less frequent and yielded smaller colonies, however, perhaps reflecting inhibitory effects of Bcl-2 on cell cycling in specific lineages. After irradiation or factor deprivation, Bcl-2 markedly enhanced clonogenic survival of all tested progenitor and preprogenitor cells. Thus, Bcl-2 has multiple effects on the hematopoietic system. These mice should help to further clarify the role of apoptosis in the development and homeostasis of this compartment.

MicroRNAs (miRNAs) are short, single-stranded RNAs that regulate gene expression at the post-transcriptional level. Recent research has shown that miRNAs and their target mRNAs are differentially expressed in endometriosis and other disorders of the female reproductive system. Since miRNAs control a broad spectrum of normal and pathological cellular functions, they may play pivotal roles in the pathogenesis of these disorders. A systematic review was undertaken of the published literature on; (i) the expression and functions of miRNAs in mammalian female reproductive tissues with a focus on endometriosis and the malignancies and fertility disorders related to this disease; and (ii) the potential roles played by validated mRNA targets of endometriosis-associated miRNAs. The current understanding of the biology of miRNAs is overviewed and the potential diagnostic and therapeutic potential of miRNAs in endometriosis is highlighted. The differential expression of miRNAs in endometriosis, and the putative molecular pathways constituted by their targets, suggests that miRNAs may play an important role in endometriotic lesion development. Models for miRNA regulatory functions in endometriosis are presented, including those associated with hypoxia, inflammation, tissue repair, TGFbeta-regulated pathways, cell growth, cell proliferation, apoptosis, extracellular matrix remodelling and angiogenesis. In addition, specific miRNAs which may be associated with malignant progression and subfertility in endometriosis are discussed. miRNAs appear to be potent regulators of gene expression in endometriosis and its associated reproductive disorders, raising the prospect of using miRNAs as biomarkers and therapeutic tools in endometriosis.