Abstract-The balance between proangiogenic and antiangiogenic factors, such as vascular endothelial growth factor, placental growth factor, and soluble fms-like tyrosine kinase-1 (sFlt-1), is altered in preeclampsia, and this dysregulation of angiogenic factors may be important in the pathogenesis of preeclampsia. Although sFlt-1 is elevated in preeclampsia, the mechanisms responsible for increasing this antiangiogenic factor remain unclear. We hypothesized that the hypertension produced by reduced uterine perfusion pressure (RUPP) is associated with increased sFlt-1 expression and decreased plasma vascular endothelial growth factor and placental growth factor concentrations in the pregnant rat. Arterial pressure was increased (130Ϯ3 versus 100Ϯ2 mm Hg; PϽ0.01) in the RUPP rats compared with the normal pregnant control rats. Plasma sFlt-1 concentration (660Ϯ270 versus 82Ϯ26 pg/mL; PϽ0.05) was increased, whereas plasma free placental growth factor (0.28Ϯ0.05 versus 1.7Ϯ0.5 pg/mL; PϽ0.01) and vascular endothelial growth factor (594Ϯ34 versus 830Ϯ33 pg/mL; PϽ0.01) concentrations were decreased in the RUPP rats compared with normal pregnant rats. Plasma sFlt-1:placental growth factor (37.2Ϯ7.8 versus 8.9Ϯ1.6; PϽ0.02) and sFlt-1:vascular endothelial growth factor (0.86Ϯ0.22 versus 0.28Ϯ0.06; PϽ0.05) ratios were increased in the RUPP rats compared with normal pregnant rats. Immunoreactive placental sFlt-1 was increased (1.1Ϯ0.1 versus 0.3Ϯ0.1; PϽ0.01) in RUPP rats contrasted with the normal pregnant rats. These findings support our hypothesis that RUPP increases the expression of sFlt-1 and alters the balance of angiogenic factors in the maternal circulation. These data also indicate that the RUPP model of pregnancy-induced hypertension may provide an invaluable model for mechanistic studies into the role of sFlt-1 in the pathogenesis preeclampsia. Key Words: preeclampsia Ⅲ gestation Ⅲ VEGF Ⅲ blood pressure Ⅲ angiogenic P regnancy-induced hypertension (PIH), or preeclampsia, is a major obstetric problem and a significant source of maternal and neonatal morbidity and mortality. 1 Although PIH continues to affect Ϸ8% of all pregnancies, the incidence of preeclampsia has seen a 40% increase in recent years. 2 Although PIH has been well characterized, with many studies indicating that proteinuria, edema, endothelial cell dysfunction, and insufficient placentation are all hallmarks of this disorder, 3,4 the mechanisms underlying the pathogenesis of this dreaded condition remain obscure. The continuing uncertainties regarding the mechanisms underlying the pathogenesis of preeclampsia are at least in part attributable to the difficulties in performing mechanistic studies in pregnant women. 5,6 Thus, the continued characterization and development of animal models for mechanistic research of preeclampsia remains an important endeavor.Recent studies have reported the existence of an imbalance between proangiogenic and antiangiogenic factors, such as vascular endothelial growth factor (VEGF), placental growth factor (PlGF), and ...

Abstract-Reductions in uterine perfusion pressure (RUPP) in pregnant rats is associated with increased tumor necrosis factor-␣ (TNF-␣). This study was designed to determine the role of endogenous TNF-␣ in mediating changes in arterial pressure and endothelin-1 (ET-1) in RUPP rats. To achieve this goal we examined the effect of RUPP in the presence and absence of a TNF-␣-soluble receptor, etanerecept (0.4 mg/kg). Mean arterial pressure increased from 102Ϯ1 mm Hg in normal pregnant (NP) rats to 134Ϯ3 mm Hg (PϽ0.05) in RUPP rats. Serum TNF-␣ increased to 40Ϯ7.6 pg/mL in RUPP rats (nϭ24)

Diabetic cardiomyopathy is manifested by compromised systolic and diastolic function. This study was designed to examine the role of advanced glycation endproduct (AGE) and AGE receptor (RAGE) in diabetic cardiomyopathy. Heart function was assessed in isolated control and streptozotocin‐induced diabetic hearts following in vivo RAGE gene knockdown using RNA interference. Cardiomyocyte mechanical properties were evaluated including peak shortening (PS), time‐to‐PS (TPS) and time‐to‐90% relengthening (TR90). RAGE was assayed by RT‐PCR and immunoblot. Diabetes significantly enhanced cardiac MG, AGE and RAGE levels accompanied with colocalization of AGE and RAGE in cardiomyocytes. Diabetes‐elicited increase in RAGE was inhibited by in vivo siRNA interference. The AGE formation inhibitor benfotiamine significantly attenuated diabetes‐induced elevation in MG, AGE, RAGE and collagen cross‐linking without affecting hypertriglyceridaemia and hypercholesterolaemia in diabetes. Diabetes markedly decreased LV contractility, as evidenced by reduced ±dP/dt and LV developed pressure (LVDP), which were protected by RAGE gene knockdown. In addition, MG‐derived AGE (MG‐AGE) up‐regulated cardiac RAGE mRNA and triggered cardiomyocyte contractile dysfunction reminiscent of diabetic cardiomyopathy. The MG‐AGE‐elicited prolongation of TPS and TR90 was ablated by an anti‐RAGE antibody in cardiomyocytes. Interestingly, MG‐AGE‐induced cardiomyocyte dysfunction was associated with mitochondrial membrane potential (MMP) depolarization and reduced GSK‐3β inactivation in control cardiomyocytes, similar to those from in vivo diabetes. Treatment with siRNA‐RAGE ablated diabetes‐induced MMP depolarization and GSK‐3β inactivation. Collectively, our result implicated a role of AGE‐RAGE in the pathogenesis of diabetic cardiomyopathy.

BackgroundMitochondrial aldehyde dehydrogenase (ALDH2) displays some promise in the protection against cardiovascular diseases although its role in diabetes has not been elucidated.MethodsThis study was designed to evaluate the impact of ALDH2 on streptozotocin-induced diabetic cardiomyopathy. Friendly virus B(FVB) and ALDH2 transgenic mice were treated with streptozotocin (intraperitoneal injection of 200 mg/kg) to induce diabetes.ResultsEchocardiographic evaluation revealed reduced fractional shortening, increased end-systolic and -diastolic diameter, and decreased wall thickness in streptozotocin-treated FVB mice. Streptozotocin led to a reduced respiratory exchange ratio; myocardial apoptosis and mitochondrial damage; cardiomyocyte contractile and intracellular Ca2+ defects, including depressed peak shortening and maximal velocity of shortening and relengthening; prolonged duration of shortening and relengthening; and dampened intracellular Ca2+ rise and clearance. Western blot analysis revealed disrupted phosphorylation of Akt, glycogen synthase kinase-3β and Foxo3a (but not mammalian target of rapamycin), elevated PTEN phosphorylation and downregulated expression of mitochondrial proteins, peroxisome proliferator-activated receptor γ coactivator 1α and UCP-2. Intriguingly, ALDH2 attenuated or ablated streptozotocin-induced echocardiographic, mitochondrial, apoptotic and myocardial contractile and intracellular Ca2+ anomalies as well as changes in the phosphorylation of Akt, glycogen synthase kinase-3β, Foxo3a and phosphatase and tensin homologue on chromosome ten, despite persistent hyperglycemia and a low respiratory exchange ratio. In vitro data revealed that the ALDH2 activator Alda-1 and glycogen synthase kinase-3β inhibition protected against high glucose-induced mitochondrial and mechanical anomalies, the effect of which was cancelled by mitochondrial uncoupling.ConclusionsIn summary, our data revealed that ALDH2 acted against diabetes-induced cardiac contractile and intracellular Ca2+ dysregulation, possibly through regulation of apoptosis, glycogen synthase kinase-3β activation and mitochondrial function independent of the global metabolic profile.

Background & Aims Mitochondrial aldehyde dehydrogenase (ALDH2) plays a critical role in the detoxification of the ethanol metabolite acetaldehyde. This study was designed to examine the impact of global ALDH2 overexpression on alcohol-induced hepatic steatosis. Methods Wild-type friendly virus B (FVB) and ALDH2 transgenic mice were placed on a 4% alcohol or control diet for 12 weeks. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin and cholesterol, hepatic triglyceride, steatosis, fat metabolism-related proteins, pro-inflammatory cytokines, glutathione (GSH), oxidized glutathione (GSSG), autophagy and autophagy signaling were examined. The role of autophagy was evaluated in ADH1-transfected human hepatocellular liver carcinoma cells (VA-13) treated with or without autophagy inducer rapamycin and lysosomal inhibitors. Results Chronic alcohol intake led to elevated AST, ALT, bilirubin, AST/ALT ratio, cholesterol, hepatic triglycerides, hepatic fat deposition as evidenced by H&E and oil Red O staining, associated with disturbed fat metabolism-related proteins (fatty acid synthase, SCD1), upregulated interleukin-6, TNF-α, cyclooxygenase, oxidative stress, and loss of autophagy, the effects of which were attenuated or ablated by ALDH2 transgene. Moreover, ethanol (100 mM) and acetaldehyde (100, 500 μM) increased levels of IL-6 and IFN-γ, and suppressed autophagy in VA-13 cells, the effects of which were markedly alleviated by rapamycin. In addition, lysosomal inhibitors mimicked ethanol-induced p62 accumulation with little additive effect with ethanol. Ethanol significantly suppressed LC3 conversion in the presence of lysosomal inhibitors. Conclusions In summary, our results revealed that ALDH2 plays a beneficial role in ameliorating chronic alcohol intake-induced hepatic steatosis and inflammation through regulation of autophagy.