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Background: Mitochondrial diabetes is primarily caused by β-cell failure, a cell type whose unique properties are important in pathogenesis. Methods: By reducing glucose, we induced energetic stress in two rodent β-cell models to assess effects on cellular function. Results: Culturing rat insulin-secreting INS-1 cells in low glucose conditions caused a rapid reduction in whole cell respiration, associated with elevated mitochondrial reactive oxygen species production, and an altered glucose-stimulated insulin secretion profile. Prolonged exposure to reduced glucose directly impaired mitochondrial function and reduced autophagy. Conclusions: Insulinoma cell lines have a very different bioenergetic profile to many other cell lines and provide a useful model of mechanisms affecting β-cell mitochondrial function.

The immunological interaction between the mother and fetus has classically been thought of as one between paternal antigen and maternal T cells. However, the MHC antigen expression on human trophoblast and the immune cell populations present in the decidua suggest that this interaction primarily involves decidual NK cells rather than T cells, and this is supported by new functional studies. It is becoming apparent also that the maternal systemic immune response in pregnancy (Th1/Th2 shift) primarily involves NK cells. Aberrant NK cell activation both locally in the decidua and systemically in the maternal blood may be the cause of pre-eclampsia.

A technical and financial pre-feasibility study of an energy from waste project in Colombia is presented. The current situation in Colombia, the technologies available, and the tools for the simula ...

A bias of T cell immunity towards type 2 (Th2) is thought to be critical for normal pregnancy. Pathological pregnancies, such as pre-eclampsia, are characterised by cell-mediated (Th1) immune dominance. The Th1/Th2 paradigm, however, is too simplistic. Normal pregnancy is associated with a systemic inflammatory response which increases throughout gestation. This inflammatory response is exaggerated in pre-eclampsia, a syndrome of the third trimester. T helper (Th) cells are considered the primary mediators of these altered immune responses, and other T cells, i.e. T cytotoxic (Tc) cells, and lymphocytes of the innate immune system, i.e. natural killer (NK) and NKT cells, have been largely disregarded. In this study, we have used novel pan type 1 (IL-18 receptor) and pan type 2 (ST2L) lymphocyte function markers in four-colour flow cytometry to broadly characterise peripheral blood lymphocyte populations from non-pregnant, normal pregnant and pre-eclamptic women. There were no changes in the Th1/Th2 or Tc1/Tc2 cell ratios between the three groups; however, the NK1/NK2 and NKT1/NKT2 cell ratios were significantly decreased in normal pregnancy compared with non-pregnant (p

In mice and women, terminal differentiation of uterine natural killer (uNK) cells commences during endometrial decidualization. Both proliferation and interferon (IFN)-g are induced. Uterine NK cell precursors appear to home from secondary lymphoid organs to decidualizing uteri and localize mesometrially to the central decidua basalis, the site of maternal arterial modification at Gestation Days (gd) 9.5‐10. In mice, genetic absence of uNK cells results in absence of pregnancy-induced spiral artery modification. Administration of IFN-g to uNK-negative pregnant females induces arterial modifications without fetal loss. In this study, we investigated the roles of cytokines, known in other tissues to differentiate and activate NK cells, in induction of IFN-g production in normal mouse implantation sites. Fecundity evaluation, implantation site morphometry, and IFNg quantification in interleukin (IL)-12p400/0, IL-180/0, dual IL12p400/0/IL-180/0 and congenic strains revealed the importance of both IL-12 and IL-18 in the induction of spiral artery modification and IFN-g synthesis. Immediately after implantation, IL18 was localized transiently to decidual cells, but by gd8, IL-18 was produced solely by uNK cells, suggesting that early uNK cells are activated by stroma and lymphocyte-derived signals maintain later uNK cell activation. Mesometrial tissue of C57Bl/ 6J mice was examined by reverse transcription polymerase chain reaction assay in virgin, early postimplantation, and midgestation females for expression of the heterodimeric cytokines IL-23 (composed of IL-12p40 and a novel a chain), IL-27 (composed of two IL-12-related chains) and IL-27R. No expression was detected in virgin uteri. The four genes were induced by gd6, and uNK cells isolated from midgestation transcribed IL-23a and IL27R. This study advances the understanding of uNK cell activation during normal pregnancy. decidua, growth factors, immunology, pregnancy, uterus

In adult females of many species, a transient population of natural killer (NK) cells appears in cycles within the uterine endometrium (lining). Appearance of these lymphocytes coincides with specific phases of the ovarian hormone cycle and/or early pregnancy. Studies in rodents, women, and pigs dominate the literature and suggest the uterine (u)NK cells are an activated subset sharing many but not all features with circulating or lymphoid organ-residing NK cells. During successful murine pregnancy, uNK cells appear to regulate initiation of structural changes in the feed arterial systems that support maternal endometrial tissue at sites of implantation and subsequent placental development. These changes, which reverse after pregnancy, create a higher volume arterial bed with flaccid vessels unresponsive to vasoactive compounds. These unique pregnancy-associated arterial changes elevate the volume of low-pressure, nutrient-rich, maternal arterial blood available to conceptuses. Regulation of the differentiation, activation, and functions of uNK cells is only partially known, and there is lively debate regarding whether and how uNK cells participate in infertility or spontaneous abortion. This review highlights the biology of uNK cells during successful pregnancy.

Pre-eclampsia is a major disorder of human pregnancy, which may have an immunological basis. It is a disease of two stages. The first stage concerns the relative failure of early trophoblast invasion and remodelling of the spiral arteries, leading to a poor blood supply to the placenta, exposing it to oxidative stress. The inadequate trophoblast invasion may result from decreased expression of human leukocyte antigen-G (HLA-G) leading to an abnormal interaction with decidual natural killer (NK) cells, which are believed to play a major role in these processes through the production of immunoregulatory cytokines and angiogenic factors. Recent evidence suggests that the interaction between trophoblast human leukocyte antigen-C (HLA-C) molecules and decidual NK cell receptors may be the point at which the apparent partner specificity of the disease originates. The second stage is the maternal syndrome, which is characterized by a generalized systemic inflammatory response involving both leukocytes and endothelium. The inflammatory stimulus is believed to come from the placenta. In pre-eclampsia, placental oxidative stress may lead to increased shedding of apoptotic and/or necrotic syncytiotrophoblast debris into the maternal circulation. There is evidence that such trophoblast debris interacts with maternal leukocytes and endothelial cells to stimulate the release of proinflammatory cytokines, which could then trigger the maternal disease.

Pre-eclampsia is a common and potentially dangerous disorder of human pregnancy. The maternal syndrome of hypertension, proteinuria and oedema is part of a severe systemic inflammatory response that includes leukocyte and endothelial cell activation. Although the origins of pre-eclampsia remain unclear, a major cause is the failure to develop an adequate blood supply to the placenta, leading to placental oxidative stress. This results in the excess release of placental factors, such as syncytiotrophoblast debris or soluble fms-like tyrosine kinase-1 (sFlt-1), the soluble receptor for vascular endothelial growth factor (VEGF), into the maternal circulation, where they trigger an inflammatory response and endothelial dysfunction. Alternatively, pre-eclampsia can develop in the presence of a normal placenta in women that are susceptible to systemic inflammation, such as with chronic cardiovascular disease or diabetes. While clinical management of pre-eclampsia does not currently include anti-inflammatory agents, current research is focusing on ways to reduce inflammation and oxidative stress.

Successful pregnancy is biased towards humoral (Th2) immune responses, while pathological pregnancies, including pre-eclampsia, are characterized by cell-mediated (Th1) immune responses. The Th1/Th2 paradigm is however, too simplistic since normal pregnancy is characterized by innate immune activation causing a systemic inflammatory response. This is exaggerated in pre-eclampsia. There were two main aims of this thesis. The first was to investigate a role for lymphocytes of the innate immune system in the type 1/type 2 changes during healthy pregnancy and pre-eclamptia. The second was to investigate a role for syncytiotrophoblast microparticles (STBMs), shed from the placenta into the maternal circulation, in the systemic inflammatory response of pregnancy. In Chapter 1, evidence is presented demonstrating a role for NK and NK-like T cells in the type 2 immune bias of healthy pregnancy, which was evident from twelve weeks of gestation in CD56bright NK cells. Changes in CD56dim NK, NK-like T and Th cells were only apparent during third trimester pregnancy, relative to non-pregnant and pre-eclamptic women, who were characterized by a type 1 immune bias. It is unclear what triggers immune changes during pregnancy. However, STBMs may cause leukocyte activation and pro-inflammatory cytokine production, which in turn alter lymphocyte immune responses. In Chapter 2, circulating dendritic cells are shown to bind to STBMs in the periphery during pregnancy. Although the mechanisms of this interaction are not known, changes in the expression of toll-like receptors 2, 4 and 9 and CD14 suggest they may play a role. In Chapter 3, an in vitro model is presented for investigating STBM-induced leukocyte activation that was assessed through pro-inflammatory cytokine production. Following STBM stimulation, production of IL-8, IL-12 and TNF-[alpha] was found by leukocytes from non-pregnant women. The results presented in this thesis support innate immune activation during the systemic inflammatory response of pregnancy. It is hypothesized that circulating maternal leukocytes, particularly dendritic cells, are activated by STBMs through CD14 and TLRs, causing pro-inflammatory cytokine production and the systemic inflammatory response. In pre-eclampsia, where this response is excessive, the result is an overall shift to a type 1 immune bias in both T and NK cells.

In primates, including women, and in rodents, natural killer lymphocytes (NK cells) have a unique relationship with the decidualizing uterus. Implantation sites from genetically modified and transplanted mice have proven useful models for understanding potential mechanisms involved in the recruitment, activation and functions of human CD56(bright) uterine (u)NK cells. Key findings are reviewed in this article. In mice, uNK precursor cells are recruited from secondary lymphoid tissues and are activated coincident with their uterine arrival. uNK cells proliferate, produce cytokines (interferon gamma (IFN-gamma) and interleukin 18 (IL-18) and IL-27), and terminally differentiate into granulated lymphocytes. Many uNK cells proliferate within the myometrium at each implantation site forming a structure, the mesometrial lymphoid aggregate of pregnancy (MLAp) that surrounds blood vessels servicing each placenta. Post-mitotic uNK cells are abundant within decidua basalis; frequently (

In mice and women, terminal differentiation of uterine natural killer (uNK) cells commences during endometrial decidualization. Both proliferation and interferon (IFN)-gamma are induced. Uterine NK cell precursors appear to home from secondary lymphoid organs to decidualizing uteri and localize mesometrially to the central decidua basalis, the site of maternal arterial modification at Gestation Days (gd) 9.5-10. In mice, genetic absence of uNK cells results in absence of pregnancy-induced spiral artery modification. Administration of IFN-gamma to uNK-negative pregnant females induces arterial modifications without fetal loss. In this study, we investigated the roles of cytokines, known in other tissues to differentiate and activate NK cells, in induction of IFN-gamma production in normal mouse implantation sites. Fecundity evaluation, implantation site morphometry, and IFN-gamma quantification in interleukin (IL)-12p40(0/0), IL-18(0/0), dual IL-12p40(0/0)/IL-18(0/0) and congenic strains revealed the importance of both IL-12 and IL-18 in the induction of spiral artery modification and IFN-gamma synthesis. Immediately after implantation, IL-18 was localized transiently to decidual cells, but by gd8, IL-18 was produced solely by uNK cells, suggesting that early uNK cells are activated by stroma and lymphocyte-derived signals maintain later uNK cell activation. Mesometrial tissue of C57Bl/6J mice was examined by reverse transcription polymerase chain reaction assay in virgin, early postimplantation, and midgestation females for expression of the heterodimeric cytokines IL-23 (composed of IL-12p40 and a novel alpha chain), IL-27 (composed of two IL-12-related chains) and IL-27R. No expression was detected in virgin uteri. The four genes were induced by gd6, and uNK cells isolated from midgestation transcribed IL-23alpha and IL-27R. This study advances the understanding of uNK cell activation during normal pregnancy.