These data demonstrate that IL-17 activates RhoA/Rho-kinase leading to endothelial dysfunction and hypertension. Inhibitors of IL-17 or Rho-kinase may prove useful as anti-hypertensive drugs in IL-17-associated autoimmune diseases.

Inflammation mediated by both innate and adaptive immune cells is necessary for several important processes during pregnancy. Pro-inflammatory immune cell activation plays a critical role in embryo implantation, placentation, and parturition; however dysregulation of these cells can lead to detrimental pregnancy outcomes including spontaneous abortion, fetal growth restriction, maternal pathology including hypertensive disorders, or fetal and maternal death. The resolution of inflammation plays an important role throughout pregnancy and is largely mediated by immune cells that produce interleukin (IL)-4 and IL-10. The temporal and spatial aspects of reducing inflammation during pregnancy represent a complex process that if not functioning optimally can lead to persistent inflammation and pregnancy complications. In this review, we examine how immune cells that produce IL-4 and IL-10 are regulated throughout pregnancy as well as the effects that reduced IL-4 and IL-10 signaling has on fetal and maternal physiology.

Mutations in the cardiac ryanodine receptor 2 (RyR2) have been associated with catecholaminergic polymorphic ventricular tachycardia and a form of arrhythmogenic right ventricular dysplasia. To study the relationship between RyR2 function and these phenotypes, we developed knockin mice with the human disease-associated RyR2 mutation R176Q. Histologic analysis of hearts from RyR2 R176Q/؉ mice revealed no evidence of fibrofatty infiltration or structural abnormalities characteristic of arrhythmogenic right ventricular dysplasia, but right ventricular end-diastolic volume was decreased in RyR2 R176Q/؉ mice compared with controls, indicating subtle functional impairment due to the presence of a single mutant allele. Ventricular tachycardia (VT) was observed after caffeine and epinephrine injection in RyR2 R176Q/؉ , but not in WT, mice. Intracardiac electrophysiology studies with programmed stimulation also elicited VT in RyR2 R176Q/؉ mice. Isoproterenol administration during programmed stimulation increased both the number and duration of VT episodes in RyR2 R176Q/؉ mice, but not in controls. Isolated cardiomyocytes from RyR2 R176Q/؉ mice exhibited a higher incidence of spontaneous Ca 2؉ oscillations in the absence and presence of isoproterenol compared with controls. Our results suggest that the R176Q mutation in RyR2 predisposes the heart to catecholamine-induced oscillatory calcium-release events that trigger a calcium-dependent ventricular arrhythmia.arrhythmogenic right ventricular dysplasia ͉ catecholaminergic polymorphic ventricular tachycardia ͉ calcium-release channel T he cardiac ryanodine receptor 2 (RyR2) regulates calcium release from the sarcoplasmic reticulum in cardiomyocytes (1). Two inherited arrhythmogenic syndromes have been linked to mutations in RyR2, arrhythmogenic right ventricular dysplasia (ARVD) and catecholaminergic polymorphic ventricular tachycardia (CPVT) (2, 3). ARVD and CPVT are both characterized by ventricular arrhythmias and a high rate of juvenile sudden death. Patients with CPVT exhibit catecholamine-induced bidirectional ventricular tachycardia (VT) in the setting of a structurally normal heart, whereas patients with ARVD exhibit progressive fibrofatty replacement of the right ventricular myocardium in addition to polymorphic VT. ARVD arising from RyR2 mutations (ARVD2) is typically associated with exercise-induced ventricular arrhythmias and relatively mild structural abnormalities compared with other forms of ARVD and, in some ways, mimics the CPVT phenotype. In fact, the diagnosis of ARVD2 in patients with RyR2 mutations is controversial because of the differences in degree of cardiac structural abnormalities between ARVD2 and other forms of ARVD (4).Disease-causing mutations in RyR2 and the skeletal muscle isoform RyR1 cluster in three highly conserved regions: a cytosolic N-terminal region, a cytosolic central region, and a C-terminal portion containing the transmembrane and pore regions of the channel (5, 6). Multiple mutations in RyR2 have been reported in patients with ...

Preeclampsia (PE) is a pregnancy-specific hypertensive syndrome characterized by excessive maternal immune system activation, inflammation, and endothelial dysfunction. Toll-like receptor (TLR) 3 activation by double-stranded RNA (dsRNA) and TLR7/8 activation by single-stranded RNA (ssRNA) expressed by viruses and/or released from necrotic cells initiates a pro-inflammatory immune response; however it is unknown whether viral/endogenous RNA is a key initiating signal that contributes to the development of PE. We hypothesized that TLR3/7/8 activation will be evident in placentas of women with PE, and sufficient to induce PE-like symptoms in mice. Placental immunoreactivity and mRNA levels of TLR3, TLR7, and TLR8 were increased significantly in women with PE compared to normotensive women. Treatment of human trophoblasts with the TLR3 agonist polyinosine-polycytidylic acid (poly I:C), the TLR7-specific agonist imiquimod (R-837), or the TLR7/8 agonist CLO97 significantly increased TLR3/7/8 levels. Treatment of mice with poly I:C, R-837, or CLO97 caused pregnancy-dependent hypertension, endothelial dysfunction, splenomegaly, and placental inflammation. These data demonstrate that RNA-mediated activation of TLR3 and TLR7/8 plays a key role in the development of PE.

Abstract-Preeclampsia may result from overactivation of the maternal immune system and is characterized by endothelial dysfunction and excessive inflammation. Given the importance of maternal immune system regulation and antiinflammatory cytokines in normotensive pregnancies, we hypothesized that maternal immune system activation via Toll-like receptor 3 during pregnancy would cause preeclampsia-like symptoms in mice, which would be made worse by deficiency of the anti-inflammatory cytokine interleukin 10. The Toll-like receptor 3 agonist polyinosinepolycytidylic acid (poly I:C) caused hypertension, endothelial dysfunction, and proteinuria in mice only when pregnant.In the absence of poly I:C, pregnant interleukin 10 knockout mice exhibited a significant increase in systolic blood pressure, endothelial dysfunction, and serum proinflammatory cytokines, as well as aortic and placental platelet-endothelial cell adhesion molecule expression compared with pregnant wild-type mice. Deficiency of interleukin 10 further augmented these measures in poly I:C-treated pregnant mice. In addition, sera from poly I:C-treated pregnant wild-type mice significantly decreased relaxation responses and increased platelet-endothelial cell adhesion molecule expression in isolated aortas from nonpregnant wild-type mice, and these effects were augmented by sera from poly I:C-treated interleukin 10 knockout mice. Coincubation with recombinant interleukin 10 normalized relaxation responses and platelet-endothelial cell adhesion molecule expression in all of the groups. Collectively, Toll-like receptor 3 activation during pregnancy causes preeclampsia-like symptoms, which are exacerbated by the absence of interleukin 10. Exogenous interleukin 10 treatment had beneficial effects on endothelial function and may be beneficial in women with preeclampsia. Key Words: interleukin 10 Ⅲ endothelium Ⅲ hypertension Ⅲ pregnancy-induced Ⅲ inflammation Ⅲ pregnancy Ⅲ preeclampsia H ypertensive disorders of pregnancy, such as preeclampsia (PE), affect Ϸ10% of all pregnancies, are one of the leading causes of fetal morbidity and mortality, and cause 15% to 20% of maternal deaths worldwide. 1 PE is diagnosed by new-onset hypertension and proteinuria during pregnancy and is associated with endothelial dysfunction, excessive inflammation, and abnormal fetal development. [2][3][4][5] Although the etiology of PE remains unknown, evidence strongly supports a role for the maternal immune system. 6 PE is more common in women with autoimmune diseases and during the first conception, and conversely, the incidence of PE is decreased in women with immune deficiency

Background Heart failure with preserved ejection fraction (HFpEF) accounts for approximately 50% of all cases of heart failure and currently has no effective treatment. Diastolic dysfunction underlies HFpEF; therefore, elucidation of the mechanisms that mediate relaxation can provide new potential targets for treatment. Cardiac myosin binding protein-C (cMyBP-C) is a thick filament protein that modulates cross-bridge cycling rates via alterations in its phosphorylation status. Thus, we hypothesize that phosphorylated cMyBP-C accelerates rate of cross-bridge detachment, thereby enhancing relaxation to mediate diastolic function. Methods and Results We compared mouse models expressing phosphorylation deficient cMyBP-C(S273A/S282A/S302A)-cMyBP-C(t3SA), phosphomimetic cMyBP-C(S273D/S282D/S302D)-cMyBP-C(t3SD), and WT-control cMyBP-C(tWT) to elucidate the functional effects of cMyBP-C phosphorylation. Decreased voluntary running distances, increased lung/body weight ratios, and increased brain natriuretic peptide (BNP) levels in cMyBP-C(t3SA) mice demonstrate that phosphorylation deficiency is associated with signs of heart failure. Echocardiography (ejection fraction, myocardial relaxation velocity) and pressure/volume measurements (−dP/dtmin, pressure decay time constant Tau-Glantz, passive filling stiffness) show that cMyBP-C phosphorylation enhances myocardial relaxation in cMyBP-C(t3SD) mice while deficient cMyBP-C phosphorylation causes diastolic dysfunction with preserved ejection fraction in cMyBP-C(t3SA) mice. Simultaneous force and [Ca2+]i measurements on intact papillary muscles show that enhancement of relaxation in cMyBP-C(t3SD) mice and impairment of relaxation in cMyBP-C(t3SA) mice are not due to altered [Ca2+]i handling, implicating that altered cross-bridge detachment rates mediate these changes in relaxation rates. Conclusions cMyBP-C phosphorylation enhances relaxation while deficient phosphorylation causes diastolic dysfunction and phenotypes resembling HFpEF. Thus, cMyBP-C is a potential target for treatment of HFpEF.

Cholangiocarcinomas are cancers that have poor prognosis and limited treatment options. The noncanonical Wnt pathway is mediated predominantly by Wnt 5a, which activates a Ca(2+)-dependent pathway involving protein kinase C, or a Ca(2+)-independent pathway involving the orphan receptor Ror2 and subsequent activation of Jun NH(2)-terminal kinase (JNK). This pathway is associated with growth-suppressing effects in numerous cell types. We have shown that anandamide decreases cholangiocarcinoma growth in vitro. Therefore, we determined the effects of anandamide on cholangiocarcinoma tumor growth in vivo using a xenograft model and evaluated the effects of anandamide on the noncanonical Wnt signaling pathways. Chronic administration of anandamide decreased tumor growth and was associated with increased Wnt 5a expression in vitro and in vivo. Treatment of cholangiocarcinoma cells with recombinant Wnt 5a decreased cell proliferation in vitro. Neither anandamide nor Wnt 5a affected intracellular calcium release, but both increased the JNK phosphorylation. Stable knockdown of Wnt 5a or Ror2 expression in cholangiocarcinoma cells abolished the effects of anandamide on cell proliferation and JNK activation. Modulation of the endocannabinoid system may be important in cholangiocarcinoma treatment. The antiproliferative actions of the noncanonical Wnt signaling pathway warrants further investigation to dissect the mechanism by which this may occur.

Tinsley JH, South S, Chiasson VL, Mitchell BM. Interleukin-10 reduces inflammation, endothelial dysfunction, and blood pressure in hypertensive pregnant rats. Am J Physiol Regul Integr Comp Physiol 298: R713-R719, 2010. First published January 6, 2010 doi:10.1152/ajpregu.00712.2009.-Hypertensive disorders of pregnancy are characterized by systemic and placental inflammation; however, treatment for these conditions has remained elusive. We tested whether administration of the anti-inflammatory cytokine interleukin-10 (IL-10) during pregnancy would attenuate the hypertension, endothelial dysfunction, proteinuria, and inflammation seen in pregnant DOCA/saline-treated (PDS) rats. Normal pregnant (NP) rats and PDS were given daily intraperitoneal injections of recombinant IL-10 from gestational day 13 until death on day 20. Systolic blood pressure, aortic endothelium-dependent relaxation responses, and urinary protein excretion were measured on days 13 and 20 of gestation. Fetal number and development, plasma endothelin-1 levels, serum and placental levels of IFN␥ and IL-10, and aortic and placental levels of platelet endothelial cell adhesion molecule (PECAM) were assessed on gestational day 20. Systolic blood pressure, aortic endothelial dysfunction, and urinary protein excretion were significantly increased at gestational day 13 in PDS rats. However, all of these were restored to NP levels following IL-10 treatment in PDS rats. IL-10 treatment also significantly increased the number of pups per litter in PDS rats and did not further affect fetal development. The beneficial effects of IL-10 in PDS rats were likely mediated by the decreased plasma levels of endothelin-1, decreased levels of circulating and placental IFN␥, as well as decreased aortic and placental expression of PECAM. These data demonstrate that exogenous IL-10 can normalize blood pressure and endothelial function in pregnancy-induced hypertensive rats and may be beneficial in women with hypertensive disorders of pregnancy. preeclampsia; anti-inflammatory; hypertension; endothelin-1 PREECLAMPSIA (PE), DIAGNOSED as de novo hypertension and proteinuria during pregnancy, and other hypertensive disorders of pregnancy affect ϳ10% of pregnancies in the US and are responsible for 15-20% of maternal deaths worldwide (8). PE is associated with decreased fetal development and increased risk of future maternal heart disease. Although recent scientific findings have greatly aided in explaining the potential mechanisms involved in the development of PE, the exact causes remain unknown and effective treatments for PE remain elusive.Abnormal maternal immune system responses play a key role in the development of PE (10,13,31). A current theory is that women who develop PE have abnormal immunological responses to the fetus and placenta and that the hypertension and proteinuria represent clinical signs of a mild form of fetal rejection, while severe forms of PE result in spontaneous abortion and fetal demise. Consistent with this abnormal immunological response, cli...