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Preeclampsia is a pregnancy-specific complication with long-term negative outcomes for offspring including increased susceptibility to type 2 diabetes (T2D) in adulthood. In rat Reduced Uteroplacental Perfusion Pressure (RUPP) model of chronic placental ischemia, maternal hypertension in conjunction with intrauterine growth restriction mimics aspects of preeclampsia and resulted in female embryonic day (e)19 offspring with reduced β-cell area and increased β-cell apoptosis compared to offspring of Sham pregnancies. Decreased pancreatic β-cell area persists to Postnatal Day (PD)13 in females and could influence whether T2D develops in adulthood. Macrophage changes also occur in islets in T2D. Therefore, we hypothesized that macrophages are crucial to reduction in pancreatic β-cell area in female offspring following chronic placental ischemia. The macrophage marker CD68 mRNA expression was significantly elevated in e19 and PD13 islets isolated from female RUPP offspring compared to Sham. Postnatal injections of clodronate liposomes into female RUPP and Sham offspring on PD2 and PD9 significantly depleted macrophages compared to animals injected with control liposomes. Depletion of macrophages rescued reduced β-cell area and increased β-cell proliferation and size in RUPP offspring. Our studies suggest that the presence of macrophages is important for reduced β-cell area in female RUPP offspring and changes in macrophages could contribute to development of T2D in adulthood.

Gestational hypertension with or without low birth weight is associated with increased risk for Type 2 diabetes in offspring. Pancreatic beta cell mass is set very early in life and can influence whether an individual develops Type 2 diabetes. We previously demonstrated that postnatal day (PD)13 female offspring of rats subjected to chronic placental ischemia-induced hypertension had significantly reduced beta cell area. Previous studies in humans have noted increased circulating C3 in Type 2 diabetics, as well as an important role for intracellular complement C3 in maintaining integrity of the beta cell in the islet. Thus, we hypothesized that decreased C3 in islets is associated with reductions in beta cell area in rat offspring following placental insufficiency. The rat Reduced Uterine Perfusion Pressure (RUPP) model was used to mechanically induce placental insufficiency in the dam by placing silver clips on abdominal aorta and uterine arteries on gestation day 14 of a 21-day gestation, resulting in hypertension in the dam. Pancreatic islets and acinar were isolated by collagenase perfusion and hand picking from PD13 female offspring of RUPP and Sham dams. The concentration of C3 in serum, isolated islets and acinar was determined by ELISA. C3 was significantly increased in serum of female RUPP compared to female Sham offspring. In contrast, C3 in islets was significantly decreased in RUPP female offspring compared to Sham with no significant differences detected in acinar C3 concentrations. Thus, these data suggest that decreased C3 in islets of PD13 offspring may contribute to reduction of beta cell area and long-term susceptibility for Type 2 diabetes.

Preeclampsia is a pregnancy-specific complication with long-term negative outcomes for offspring, including increased susceptibility to type 2 diabetes (T2D) in adulthood. In a rat reduced uteroplacental perfusion pressure (RUPP) model of chronic placental ischemia, maternal hypertension in conjunction with intrauterine growth restriction mimicked aspects of preeclampsia and resulted in female embryonic day 19 (e19) offspring with reduced β-cell area and increased β-cell apoptosis compared with offspring of sham pregnancies. Decreased pancreatic β-cell area persisted to postnatal day 13 (PD13) in females and could influence whether T2D developed in adulthood. Macrophage changes also occurred in islets in T2D. Therefore, we hypothesized that macrophages are crucial to reduction in pancreatic β-cell area in female offspring after chronic placental ischemia. Macrophage marker CD68 mRNA expression was significantly elevated in e19 and PD13 islets isolated from female RUPP offspring compared with sham. Postnatal injections of clodronate liposomes into female RUPP and sham offspring on PD2 and PD9 significantly depleted macrophages compared with injections of control liposomes. Depletion of macrophages rescued reduced β-cell area and increased β-cell proliferation and size in RUPP offspring. Our studies suggest that the presence of macrophages is important for reduced β-cell area in female RUPP offspring and changes in macrophages could contribute to development of T2D in adulthood.

Preeclampsia is a prevalent pregnancy complication characterized by new-onset maternal hypertension and inflammation, with placental ischemia as the initiating event. Studies of others have provided evidence for the importance of lymphocytes in placental ischemia-induced hypertension; however, the contributions of B1 versus B2 lymphocytes are unknown. We hypothesized that peritoneal B1 lymphocytes are important for placental ischemia-induced hypertension. As an initial test of this hypothesis, the effect of anti-CD20 depletion on both B-cell populations was determined in a reduced utero-placental perfusion pressure (RUPP) model of preeclampsia. Anti-murine CD20 monoclonal antibody (5 mg/kg, Clone 5D2) or corresponding mu IgG2a isotype control was administered intraperitoneally to timed pregnant Sprague-Dawley rats on gestation day (GD)10 and 13. RUPP or sham control surgeries were performed on GD14, and mean arterial pressure (MAP) was measured on GD19 from a carotid catheter. As anticipated, RUPP surgery increased MAP and heart rate and decreased mean fetal and placental weight. However, anti-CD20 treatment did not affect these responses. On GD19, B-cell populations were enumerated in the blood, peritoneal cavity, spleen, and placenta with flow cytometry. B1 and B2 cells were not significantly increased following RUPP. Anti-CD20 depleted B1 and B2 cells in peritoneum and circulation but depleted only B2 lymphocytes in spleen and placenta, with no effect on circulating or peritoneal IgM. Overall, these data do not exclude a role for antibodies produced by B cells before depletion but indicate the presence of B lymphocytes in the last trimester of pregnancy is not critical for placental ischemia-induced hypertension.NEW & NOTEWORTHY The adaptive and innate immune systems are implicated in hypertension, including the pregnancy-specific hypertensive condition preeclampsia. However, the mechanism of immune system dysfunction leading to pregnancy-induced hypertension is unresolved. In contrast to previous reports, this study reveals that the presence of classic B2 lymphocytes and peritoneal and circulating B1 lymphocytes is not required for development of hypertension following third trimester placental ischemia in a rat model of pregnancy-induced hypertension.

Placental insufficiency can result in gestational hypertension and/or intrauterine growth restriction (IUGR) in the offspring. Gestational hypertension with or without low birth weight is associated with increased risk for Type 2 diabetes in the offspring. Pancreatic β cell mass, set very early in life, can influence whether an individual develops Type 2 diabetes. Our previous studies demonstrated a significant reduction in β cell area in embryonic day 19 and postnatal day (PD)13 female offspring of rats subjected to chronic placental ischemia-induced hypertension. Previous studies in human islets demonstrated important roles for complement C3 and activation product C3a in determining β cell area, with increased C3a generation associated with prevention of islet cell atrophy. Thus, we hypothesized that increases in self-proteins that limit complement system activation, i.e. complement regulators, are associated with reductions in β cell area in the offspring following placental insufficiency. The Reduced Uterine Perfusion Pressure (RUPP) model was used to induce placental insufficiency in the dam by placing silver clips on the abdominal aorta and uterine arteries on gestation day 14 of a 21 day gestation to mechanically reduce placental perfusion. This results in hypertension in the dam and IUGR in the offspring. Islets from the pancreas of (PD)13 female offspring of RUPP and Sham dams were isolated by collagenase perfusion and hand picking. The transcript message for complement regulators CD55 and Crry (regulators of C3 activation) and CD59 (terminal pathway regulator) was determined using qRT-PCR. Complement regulator CD55 was significantly increased in female RUPP offspring (2.01 + 0.29 fold) compared to female Sham offspring (1.00 + 0.13 fold change; p < 0.05; 6-13 pups from 4-7 dams; mixed model ANOVA including litter effect), whereas the Crry increase of 1.38 + 0.20 fold in female RUPP vs Sham offspring was not significant (p = 0.22). No significant change was observed in message for CD59 or C3. Thus, these data suggest increased islet complement regulator CD55 may limit complement activation in islets of PD13 offspring following placental ischemia and thereby contribute to reduction of β cell area and long term susceptibility for Type 2 diabetes.

Y-box binding protein 1 (YB-1) is a regulatory protein associated with oncogenesis and poor prognosis in patients with cancer. In the cell, YB-1 functions as a DNA and RNA binding protein that promotes or suppresses expression of target genes. The cancer-promoting activity of YB-1 is mediated through its activation of oncogenes and repression of tumor suppressor genes. Lipogenic enzyme stearoyl-CoA desaturase (SCD1) drives the production of endogenous monounsaturated fatty acids (MUFAs) in cells and protects against toxic buildup of saturated fatty acids. Clear cell renal cell carcinoma (ccRCC) is often characterized by aberrantly high SCD1 expression and cytosolic accumulation of unsaturated fatty acids. In the present study, a proteomics screen of cells treated with inhibitors of SCD1 supported a potential relationship between YB-1 and SCD1. It was revealed that the presence of MUFAs led to increased protein synthesis and increased expression of high molecular weight forms of YB-1 in ccRCC cells, but not in non-tumorigenic cells. Ectopic expression of YB-1 led to decreased expression levels of SCD1 protein and mRNA in ccRCC cell lines. Conversely, targeted knockdown of YB-1 increased SCD1 mRNA abundance. Analysis of ccRCC patient data from The Cancer Proteome Atlas database showed YB-1 expression was negatively associated with survival, whereas SCD1 was associated with improved survival. These data suggested an antagonistic relationship between YB-1 and SCD1 that may influence survival of patients with ccRCC.

Preeclampsia is characterized by new onset hypertension and fetal growth restriction and is associated with aberrant activation of the innate immune complement system and stressed or ischemic placenta. Previous studies have suggested a role for both endothelin and complement system activation products in new onset hypertension in pregnancy, but inter-relationships of the pathways are unclear. We hypothesized that complement activation following placental ischemia stimulates the endothelin pathway to cause hypertension and impair fetal growth. The Reduced Uterine Perfusion Pressure (RUPP) model results in hypertension and fetal growth restriction in a pregnant rat due to placental ischemia caused by mechanical obstruction of blood flow to uterus and placenta. The effect of inhibitor of complement activation soluble Complement Receptor 1 (sCR1) and endothelin A receptor (ET(A)) antagonist atrasentan on hypertension, fetal weight, complement activation (systemic circulating C3a and local C3 placental deposition) and endothelin [circulating endothelin and message for preproendothelin (PPE), ET(A) and endothelin B receptor (ET(B) in placenta] in the RUPP rat model were determined. Following placental ischemia, sCR1 attenuated hypertension but increased message for PPE and ET(A) in placenta, suggesting complement activation causes hypertension via an endothelin independent pathway. With ET(A) antagonism the placental ischemia-induced increase in circulating C3a was unaffected despite inhibition of hypertension, indicating systemic C3a alone is not sufficient. In normal pregnancy, inhibiting complement activation increased plasma endothelin but not placental PPE message. Atrasentan treatment increased fetal weight, circulating endothelin and placental ET(A) message, and unexpectedly increased local complement activation in placenta (C3 deposition) but not C3a in circulation, suggesting endothelin controls local placental complement activation in normal pregnancy. Atrasentan also significantly decreased message for endogenous complement regulators Crry and CD55 in placenta and kidney in normal pregnancy. Results of our study indicate that complement/endothelin interactions differ in pregnancies complicated with placental ischemia vs normal pregnancy, as well as locally vs systemically. These data clearly illustrate the complex interplay between complement and endothelin indicating that perturbations of either pathway may affect pregnancy outcomes.

Evidence indicates the immune system is important in development of hypertension and kidney disease. In the Dahl Salt‐Sensitive (SS) rat model, lymphocytes play a role in development of hypertension and kidney damage after increased sodium intake. Recent transcriptomic analyses demonstrate upregulation of the innate immune complement system in the kidney of Dahl SS rat fed a high‐salt diet, leading us to hypothesize that inhibition of complement activation would attenuate development of hypertension and kidney damage. Male Dahl SS rats on a low salt (0.4% NaCl) diet were instrumented with telemeters for continuous monitoring of arterial blood pressure. Animals received saline vehicle (Control) or sCR1, a soluble form of endogenous Complement Receptor 1 (CR1; CD35) that inhibits complement activation. At Day 0, rats were switched to high salt (4.0% NaCl) diet and assigned to sCR1 (15 mg/kg per day) or Control groups with daily ip injections either days 1–7 or days 14–18. Urine was collected overnight for determination of albumin excretion. Treatment with sCR1, either immediately after high‐salt diet was initiated, or at days 14–18, did not alter development of hypertension or albuminuria. The sCR1 dose effectively inhibited total hemolytic complement activity as well as C3a generation. High salt caused an increase in message for complement regulator Cd59, with minimal change in Crry that controls the C3 convertase. Thus, innate immune complement activation in the circulation is not critical for development of hypertension and kidney damage due to increased sodium intake, and therapeutic manipulation of the complement system is not indicated in salt‐sensitive hypertension.

We have used RNASeq and qRT-PCR to study mRNA levels for all σ-factors in different Mycobacterium marinum strains under various growth and stress conditions. We also studied their levels in M. marinum from infected fish and mosquito larvae. The annotated σ-factors were expressed and transcripts varied in relation to growth and stress conditions. Some were highly abundant such as sigA, sigB, sigC, sigD, sigE and sigH while others were not. The σ-factor mRNA profiles were similar after heat stress, during infection of fish and mosquito larvae. The similarity also applies to some of the known heat shock genes such as the α-crystallin gene. Therefore, it seems probable that the physiological state of M. marinum is similar when exposed to these different conditions. Moreover, the mosquito larvae data suggest that this is the state that the fish encounter when infected, at least with respect to σ-factor mRNA levels. Comparative genomic analysis of σ-factor gene localizations in three M. marinum strains and Mycobacterium tuberculosis H37Rv revealed chromosomal rearrangements that changed the localization of especially sigA, sigB, sigD, sigE, sigF and sigJ after the divergence of these two species. This may explain the variation in species-specific expression upon exposure to different growth conditions.