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Background: Liver cirrhosis is characterized by liver fibrosis and pathological angiogenesis, which results in hyperdynamic circulation, portal-systemic collateral vascular formation, and abnormal angiogenesis. Lycopene is a nutrient mostly found in tomatoes. The beneficial effects of lycopene include anti-inflammation, anti-oxidation, anti-fibrosis, and anti-angiogenesis; however, the association between liver cirrhosis and pathological angiogenesis has yet to be studied. This study aimed to investigate the effects of lycopene on biliary cirrhotic rats. Methods: The efficacy of lycopene treatment in common bile duct ligation (BDL)-induced biliary cirrhotic rats was evaluated. Sham-operated rats served as surgical controls. Lycopene (20 mg/kg/day, oral gavage) or vehicle was administered to BDL or sham-operated rats for 4 weeks, after which the hemodynamics, liver biochemistry, portal-systemic shunting, liver and mesenteric angiogenesis, and hepatic angiogenesis-related protein expressions were examined. Results: Lycopene alleviated hyperdynamic circulation as evidenced by decreased cardiac index and increased peripheral vascular resistance (p < 0.05), but it did not affect portal pressure or liver biochemistry in the BDL rats (p > 0.05). Lycopene significantly diminished the shunting degree of portal-systemic collaterals (p = 0.04) and mesenteric vascular density (p = 0.01), and also ameliorated intrahepatic angiogenesis and liver fibrosis. In addition, lycopene upregulated endothelial nitric oxide synthase, protein kinase B (Akt) and phosphatidylinositol 3-kinases (PI3K), and downregulated vascular endothelial growth factor receptor 2 (VEGFR-2) protein expressions (p < 0.05) in the livers of the BDL rats. Conclusion: Lycopene ameliorated liver fibrosis, hyperdynamic circulation, and pathological angiogenesis in biliary cirrhotic rats, possibly through the modulation of intrahepatic Akt/PI3K/eNOS and VEGFR-2 pathways. [ABSTRACT FROM AUTHOR]

Background: Ivabradine is a funny current inhibitor which is administered to patients with congestive heart failure to reduce their heart rate (HR) and attenuate oxidative stress. Chronic liver diseases are characterized by portal hypertension and hyperdynamic circulation with tachycardia. The present study aimed to investigate the effect of ivabradine on portal hypertension. Methods: Male Sprague-Dawley rats received partial portal vein ligation (PVL) to induce portal hypertension. The PVL rats were randomly allocated to receive either vehicle or ivabradine treatment for 10 days. Then the hemodynamic data were collected. The levels of oxidative stress markers and the mRNA expression of nitric oxide synthase (NOS) were measured in the collateral vessel, the superior mesentery artery and the liver. In addition, the collateral vascular responsiveness to arginine vasopressin (AVP) was examined in the ivabradine-treated and vehicle-treated PVL rats. Results: Treatment with ivabradine significantly lowered the HR (174 ± 20 vs. 374 ± 9 beats/min; p < 0.001) and the superior mesentery arterial flow (SMAf) (6.6 ± 0.3 vs. 9.1 ± 0.7 mL/min/100 g BW; p = 0.005) of the PVL rats compared with the control group. The mean arterial pressure, cardiac index, systemic vascular resistance, portal pressure and serum levels of oxidative stress markers were not significantly affected by ivabradine treatment. In addition, the NOS expression and collateral vascular responsiveness to AVP were not significantly influenced by ivabradine treatment, either. Conclusion: Ivabradine reduced the HR and SMAf in PVL rats, which alleviated the hyperdynamic circulatory state and splanchnic hyperemia of portal hypertension. However, whether these effects would help alleviate portal hypertension-related complications requires further clinical investigations. [ABSTRACT FROM AUTHOR]

Acute or chronic insults to the liver are usually followed by a tissue repairing process. Unfortunately, this action, in most cases, is not effective enough to restore the normal hepatic structure and function. Instead, fibrogenesis and regenerative nodules formation ensue, which are relatively nonfunctioning. The common final stage of the process is liver cirrhosis with increased intrahepatic resistance to portal venous blood flow. Throughout the entire course, the extrahepatic circulatory dysfunction, including increased splanchnic blood flow, elevated portal venous blood flow and pressure, decreased splanchnic and peripheral vascular resistance, tachycardia, and increased cardiac output, are noted and denoted as portal hypertension with hyperdynamic circulatory dysfunction. When such a condition is established, patients may suffer from fatal complications such as gastroesophageal variceal hemorrhage, hepatic encephalopathy, or hepatorenal syndrome. The cause of such a circulatory dysfunction is not fully elucidated. Nevertheless, clarification of the pathophysiology definitely contributes to the control of portal hypertension-related complications. Herein, the molecular mechanism of this intriguing disaster is reviewed and discussed. [ABSTRACT FROM AUTHOR]

Abstract: Cirrhosis is associated with hyperdynamic circulation, which consists of peripheral vasodilatation and increased cardiac output. Peripheral vasodilatation is central to hyperdynamic circulation and portal hypertension in cirrhosis. However, those mechanisms underlying hyperdynamic circulation remain elusive, and are not fully understood. Most of the earlier research and attention have been focused on humoral factor abnormalities. Various gut-derived or locally produced humoral factors such as nitric oxide, endotoxin, endocannabinoids, and others have been implicated as possible mediators of hyperdynamic circulation development in cirrhosis. The associated cardiac dysfunction had been termed “cirrhotic cardiomyopathy (CCM),” which is an entity different from that seen in alcoholic heart muscle disease. Clinically, these patients present with sodium fluid retention, and strain often unmasks the presence of latent heart failure. No specific treatment can yet be recommended, but caution should be used with respect to procedures that may stress the heart such as shunt implantation and liver transplantation. Ultimately, additional research will be necessary to more accurately describe the prevalence, impact, and morbidity and survival rates for CCM, and to identify potential treatments. [Copyright &y& Elsevier]

Circulating levels of endotoxin, interleukin (IL)-6, and tumor necrosis factor (TNF)-α increase with intestinal bacterial overgrowth and translocation, and are believed to be involved in the pathogenesis of hyperdynamic circulatory syndrome and functional renal failure in patients with advanced cirrhosis. We investigated the effects of the antibiotic rifaximin on systemic hemodynamics and renal function in patients with alcohol-related cirrhosis and ascites. We measured mean arterial pressure, cardiac output (CO) by Doppler ultrasound, systemic vascular resistance (as the ratio of mean arterial pressure:CO), plasma renin activity, levels of plasma aldosterone, the glomerular filtration rate by plasma clearance of technetium-99m–DTPA, natriuresis, levels of plasma endotoxin, and serum levels of IL-6 and TNF-α in 13 patients at baseline and after 4 weeks of treatment with rifaximin. Rifaximin treatment significantly reduced CO and significantly increased systemic vascular resistance, in association with a significant decrease in plasma rennin activity. The therapy also significantly increased the glomerular filtration rate and natriuresis while reducing levels of endotoxin, IL-6, and TNF-α. Intestinal decontamination with rifaximin improved systemic hemodynamics and renal function in patients with advanced cirrhosis. [ABSTRACT FROM AUTHOR]

Abstract: Decompensated liver cirrhosis is characterized by a peripheral vasodilation with a low-resistance hyperdynamic circulation. The sustained increase of cardiac work load associated with such a condition may result in an inconstant and often subclinical series of heart abnormalities, constituting a new clinical entity known as “cirrhotic cardiomyopathy”. Cirrhotic cardiomyopathy is variably associated with baseline increase in cardiac output, defective myocardial contractility and lowered systo-diastolic response to inotropic and chronotropic stimuli, down-regulated β-adrenergic function, slight histo-morphological changes, and impaired electric “recovery” ability of ventricular myocardium. Cirrhotic cardiomyopathy is usually clinically latent or mild, likely because the peripheral vasodilation significantly reduces the left ventricle after-load, thus actually “auto-treating” the patient and masking any severe manifestation of heart failure. In cirrhotic patients, the presence of cirrhotic cardiomyopathy may become unmasked and clinically evident by certain treatment interventions that increase the effective blood volume and cardiac pre-load, including surgical or transjugular intrahepatic porto-systemic shunts, peritoneo-venous shunts (LeVeen) and orthotopic liver transplantation. Under these circumstances, an often transient overt congestive heart failure may develop, with increased cardiac output as well as right atrial, pulmonary artery and capillary wedge pressures. [Copyright &y& Elsevier]

Increased understanding of the hyperdynamic circulation syndrome has resulted in novel therapeutic approaches, some of which have already reached clinical practice. Central to the hyperdynamic circulation syndrome is an imbalance between the increase in different vasodilators (foremost among which is nitric oxide) and the compensatory increase in vasoconstrictors—usually accompanied by a blunted response. This chapter discusses the role of endothelin in the pathogenesis of the syndrome and in future treatment approaches. A relatively new area of research in this field is the role of infection and inflammation in the initiation and maintenance of the hyperdynamic circulation syndrome. The use of antibiotics in the setting of acute variceal bleeding is standard practice. Studies have suggested that chronic manipulation of the intestinal flora could have beneficial effects in the treatment of portal hypertension. The bile salts are another novel and interesting target. Although their vasoactive properties have been known for some time, recent data demonstrate that their effects could be central in the pathogenesis of the hyperdynamic circulation syndrome, and that manipulation of the composition of the bile acid pool could be a therapeutic approach to portal hypertension. Finally, hypoxia and angiogenesis play a role in the development of portal hypertension and the formation of collaterals. This role needs to be further defined but it appears likely that this phenomenon is yet another target for therapeutic intervention. [Copyright &y& Elsevier]