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Atherosclerosis progression is associated with a complex array of cellular processes in the arterial wall, including endothelial cell activation/dysfunction, chemokine-driven recruitment of immune cells, differentiation of monocytes to macrophages and their subsequent transformation into lipid laden foam cells, activation of inflammasome and pro-inflammatory signaling, and migration of smooth muscle cells from the media to the intima. The use of in vitro model systems has considerably advanced our understanding of these atherosclerosis-associated processes and they are also often used in drug discovery and other screening platforms. This chapter will describe key in vitro model systems employed frequently in atherosclerosis research.

Albumin infusion reduces the incidence of postparacentesis circulatory dysfunction among patients with cirrhosis and tense ascites compared with no treatment. Less costly treatment alternatives such as vasoconstrictors have been investigated, but the results are controversial. Midodrine, an oral α1-adrenergic agonist, increases effective circulating blood volume and renal perfusion by increasing systemic and splanchnic blood pressure. Our aim is to assess whether or not morbidity in terms of renal dysfunction, hyponatremia, systemic, or portal hemodynamics derangement or mortality differed in patients receiving albumin versus midodrine.Seventy-five patients with cirrhosis and refractory ascites were randomized to receive albumin infusion, oral midodrine for 2 days, or oral midodrine for 30 days after therapeutic large volume paracentesis (LVP). The primary endpoints were development of renal impairment or hyponatremia, change in systemic and portal hemodynamics, cost, and mortality in the short-term and long-term follow-up.No significant difference was found between groups in the development of renal impairment, hyponatremia, or mortality 6 and 30 days after LVP. A significant increase in 24-h urine sodium excretion was noted in the midodrine 30-day group. Renal perfusion improved significantly with the midodrine intake for 30 days only. The cost of midodrine therapy was significantly lower than albumin.Midodrine is as effective as albumin in reducing morbidity and mortality among patients with refractory ascites undergoing LVP at a significantly lower cost. Long-duration midodrine intake can be more useful than shorter duration intake in terms of improvement of renal perfusion and sodium excretion.

Atherosclerosis and its complications are responsible for one in three global deaths. Nutraceuticals show promise in the prevention and treatment of atherosclerosis but require an indepth understanding of the mechanisms underlying their actions. A previous study showed that the omega-6 fatty acid, dihomo-γ-linolenic acid (DGLA), attenuated atherosclerosis in the apolipoprotein E deficient mouse model system. However, the mechanisms underlying such protective effects of DGLA are poorly understood and were therefore investigated. We show that DGLA attenuates chemokine-driven monocytic migration together with foam cell formation and the expression of key pro-atherogenic genes induced by three pro-inflammatory cytokines in human macrophages. The effect of DGLA on interferon-γ signaling was mediated via inhibition of signal transducer and activator of transcription-1 phosphorylation on serine 727. In relation to anti-foam cell action, DGLA inhibits modified LDL uptake by both macropinocytosis and receptor-mediated endocytosis, the latter by reduction in expression of two key scavenger receptors (SR-A and CD36), and stimulates cholesterol efflux from foam cells. DGLA also improves macrophage mitochondrial bioenergetic profile by decreasing proton leak. Gamma-linolenic acid and prostaglandin E1, upstream precursor and key metabolite respectively of DGLA, also acted in an anti-atherogenic manner. The actions of DGLA extended to other key atherosclerosis-associated cell types with attenuation of endothelial cell proliferation and migration of smooth muscle cells in response to platelet-derived growth factor. This study provides novel insights into the molecular mechanisms underlying the anti-atherogenic actions of DGLA and supports further assessments on its protective effects on plaque regression in vivo and in human trials., Highlights • Dihomo-γ-linolenic acid (DGLA) attenuates atherosclerosis in a mouse model system. • The mechanisms underlying anti-atherogenic actions of DGLA are poorly understood. • DGLA inhibited atherogenic processes in three key cell types in this disease. • Mechanisms underlying such protective actions of DGLA were identified. • Studies inform on the beneficial anti-atherogenic actions of DGLA.

Identifying the genetic expression profile of CD133Circulating CD133Data analysis of stem cells related genes in CD133KRT15 can be used to differentiate between circulating CD133

Aim Molecular characterization of the CD133+ stem cells associated with hepatocarinogensis through identifying the expression patterns of specific microRNAs (miRNAs). Methods We investigated the expression pattern of 13 miRNAs in purified CD133+ cells separated from the peripheral blood of healthy volunteers, chronic hepatitis C (CHC), liver cirrhosis (LC) and hepatocellular carcinoma (HCC) patients a long with bone marrow samples from the healthy volunteers and the LC patients using custom miScript miRNA PCR array. Results The differential expression of the 13 studied miRNAs in CD133+ cells separated from the HCC patients' peripheral blood compared to the controls revealed that miR-602, miR-181b, miR-101, miR-122, miR-192, miR-125a-5p, and miR-221 were significantly up regulated (fold change = 1.8, 1.7, 2, 5.4, 1.6, 2.9 & 1.5 P value = 0.039, 0.0019, 0.0013, 0.0370, 00024, 0.000044 &0.000007 respectively). As for the HCC group compared to the CHC group; miR-602, miR-122, miR-181b, miR-125a-5p, and miR-192 were significantly up regulated (fold change = 13, 3.1, 2.8, 1.6 & 1.56, P value = 0.01, 0.001, 0.000004, 0.002 & 0.007 respectively). Upon comparing the HCC group to the LC group; miR-199a-3p, miR-192, miR-122, miR-181b, miR-224, miR-125a-5p, and miR-885-5p were significantly up regulated (fold change = 5, 6.7, 2.3, 3, 2.5, 4.2 & 39.5 P value = 0.001025, 0.000024, 0.000472, 0.000278, 0.000004, 0.000075 & 0.0000001 respectively) whereas miR-22 was significantly down regulated (fold change = 0.57 P value = 0.00002). Only, miR-192, miR-122, miR-181b and miR-125a-5p were significant common miRNAs in CD133+ cells of the HCC group compared to the other non-malignant groups. Conclusion We identified a miRNA panel comprised of four miRNAs (miR-192, miR-122, miR-181b and miR-125a-5p) that may serve as a molecular tool for characterization of the CD133+ cells associated with different stages of hepatocarinogensis. This panel may aid in developing a new target therapy specific for those CD133+ cells.

Oxidative stress in liver cells may contribute to the etiology of hepatic diseases, as in liver cirrhosis. AP-Endonuclease1 (APE1/Ref-1) is essential for cell protection toward oxidative stress by acting as a transcriptional regulator of pro-survival genes and as a redox sensitive protein. The aim of this study was to critically analyze the various parameters governing the success of human umbilical cord blood mononuclear stem cell-based (MNCs) therapy without the use of an immunosuppressant and to investigate for the first time the expression of APE1 during thioacetamide (TAA)-induced cirrhosis and MNCs therapy in a rat model. Umbilical cord blood samples from full-term deliveries were collected. Lethal fulminant hepatic cirrhosis in rats was induced by intraperitoneal injection of thio-acetamide. MNCs were then intrahepatically transplanted. We measured APE1 expression at mRNA and protein levels, mRNA expression of TGF-β, α-SMA, STAP, CTGF, MMP-9 and TIMP-1 in a follow up study. Histopathological and immunohistochemical analyses were performed 10 weeks after intrahepatic injection of the cells. Transdifferentiated cells could be efficiently stained with antihuman hepatocytes. Interestingly, human hepatocyte-specific markers, human albumin, cytokeratin-18 and cytokeratin-19 mRNAs were detected in rat liver after 10 days of MNCs infusion. MNC transplanted by intrahepatic route, could engraft recipient liver, differentiated into functional hepatocytes, and rescued liver failure. Moreover up regulation of APE1 expression confirmed by marked immunohistochemical staining may be involved in MNCs-induced hepatocytes regeneration suggesting that maintaining high level of APE1 has protective effect as pro-survival signal.

Benign bile duct stricture is common in surgical practice. The complications of late stricture formation and biliary sepsis still occur in bile duct reconstruction. Many biological and artificial materials have been used to replace the damaged bile duct to avoid bilio-enteric anastomosis, which bypasses the biliary sphincter mechanism. Amniotic epithelial (AE) cells are known to have unique characteristics, such as low-level expression of major histocompatibility complex antigens and a less restricted differentiation potential. AE cells differentiate into different cell types from all three germ layers, including cardiomyocytic, myocytic, osteocytic, adipocytic (mesodermal), pancreatic, hepatic (endodermal), neural, and astrocytic (neuroectodermal) cells in vitro, suggesting a promising candidate to reconstruct the damaged bile duct.Human amniotic grafts (as a source of stem cells) with or without vascularized peritoneomuscular flap were used to repair damaged bile ducts (non-circumferential and circumferential bile duct loss) in a dog model.Non-circumferential bile duct loss appeared to be satisfactorily repaired using amnion graft alone. However, circumferential duct loss was not adequately repaired with amnion graft alone, but it was adequately repaired using amnion graft with a vascularized peritoneomuscular flap. In adequately repaired cases, histological examination demonstrated that the biliary mucosal endothelium had grown over the amniotic membrane graft.Collectively, the data presented here suggest that the use of human amnion as a source of amniotic stem cells provides a very promising tool for tissue reconstruction.

The incidence of hepatocellular carcinoma (HCC) varies widely worldwide. Chronic infection with hepatitis B virus (HBV) and exposure to aflatoxins in foodstuffs are the main risk factors. AAG to AGT transversion at codon 249 of the P53 gene arg-ser (249ser) has been identified as a hotspot, reflecting DNA damage caused by aflatoxin B1 metabolites in HCC. Because HBV infection is often endemic in high aflatoxin exposure areas, it is still not clear whether HBV acts as a con-founder or as a synergistic partner in the development of the 249ser P53 mutation. Serum levels of soluble interleukin 2 receptor (sIL-2R) correlated with the progression of liver cirrhosis independently of its etiology. This fact may reflect the stimulation of T-lymphocytes, monocytes and macrophages in liver cirrhosis. The inter-relationship among aflatoxin exposure, HBVHCV infections, P53sIL-2R in patients with liver cirrhosis and hepatocellular carcinoma was studied. The results revealed significant increase in serum levels of mutant P53, sIL-2R and aflatoxin B1 in patients with cirrhosis and those with HCC compared to the controls. HCC patients showed levels of all the three parameters significantly higher than both cirrhotics and controls (P0.001). Correlations were found between serum aflatoxin B1, mutant P53 and sIL-2R in HCC group. The results were discussed.

The pre-therapeutic serum levels of VEGF and MMP-9 were studied in patients with HCC, cirrhotic patients and in healthy subjects by an ELISA assay to elucidate the relationship between serum VEGF, MMP-9 levels and clinicopathological characteristics of HCC. The serum VEGF and MMP-9 were significantly elevated in HCC patients with macroscopic portal vein invasion and with metastasis as compared to HCC patients with neither invasion nor metastasis. Serum VEGF showed a significant difference between HCC patients with tumor size5cm and5 cm, however serum MMP-9 did not vary with tumor size. It was concluded that the portal vein invasion and metastasis in HCC is a complex process involving multiple factors including VEGF-mediated angiogenesis and MMP-9 induced degradation of extracellular matrix. The pre-therapeutic serum VEGFMMP-9 in HCC might be candidate biomarkers reflecting the disease potential for vascular invasion and metastasis, serum VEGF being a superior biomarker as it correlated also with tumor size.

The natural history of hepatitis C virus (HCV) infection has a highly variable course. Many patients develop chronic infection, with its consequent risk of cirrhosis, liver failure and hepatocellular carcinoma. A key question is whether patients at high risk of disease progression can be distinguished from those with relatively benign disease course. The disease progression is influenced by other factors such as duration of infection, age at infection, sex, co-infection with hepatitis B virus (HBV), Epstein Bar virus (EBV), cytomegalovirus (CMV), the level of HCV viraemia and its type. Other endemic infections in the community as bilharziasis may have a role in progression of the condition to serious complications. These factors are correlated with newly proposed grades and stages of the disease. The studied (109) cases were divided into 6 groups according to the concomitant infection with HCV. The result proved that groups 1, 35 had a higher level of viraemia than other groups, and to be the high-risk groups as 56.4% and 34.6% were in G2S2 and G3S3, respectively. All cases of liver cell dysplasia and hepatocellular carcinoma in this study were seen in these groups. The conclusion showed that these factors play an important role in the progression of HCV infection. Death of the patients of this progressive condition occurs in younger age and is more due to liver failure than to HCC.

It has become apparent that hepatitis C virus (HCV) infection is a major risk factor for the development of hepatocellular carcinoma (HCC) worldwide. The precise mechanism by which HCV causes HCC is not known. Unlike the hepatitis B virus (HBV), HCV is not a DNA virus and does not become integrated within the genome of hepatocytes. It is more likely that HCC occurs against a background of inflammation and regeneration, associated with liver injury due to chronic hepatitis. In this study, 40 of paraffin blocks liver tissues from HCV-PCR positive patients (HBV seronegative) were examined using DNA image cytometry to evaluate its role in diagnosing HCC associated with HCV infection. Fluorescent in situ hybridization (FISH) technique using LSIZNF 217 chromosome 20q 13.2 probe was applied as well. The results showed high percentage of S-phase fraction in cases of G2S2 and G3S3 with DNA diploidy. Only two cases of G3S3 showed DNA aneuploidy with severe amplification of chromosome 20q 13.2. Consequently, DNA imaging cytometry is a good approach in differentiating dysplasia from well-differentiated HCC on top of HCV infection. In conclusion HCV has an acquired role in development of HCC through amplification of the aggressive tumor behavior oncogene LSIZNF 217 at chromosome 20q 13.2.

Hepatitis C virus (HCV) is a major cause of morbidity worldwide. The aim of this study is to evaluate hematological manifestations occurring in patients suffering from chronic HCV infection. Positive HCV-RNA cases (109) were subjected to the following C.B.C., P.T., P.T.T., B.T., C.T., detection of F.D.Ps., measurement of plasma AAT then B.M. aspiration and examination for 20 cases of them. Patients were classified into 3 groups according to the histopathological staging and grading of liver biopsy. Comparison between groups according to histopathological grading and staging for hematological and chemical parameters revealed significant statistical difference in platelets count, S. Albumin, ALT and AST levels. Comparison between groups according to histopathological grading and staging for coagulation profile, AAT level and FDPs revealed significant statistical difference regarding all parameters. Bone marrow aspiration and examination revealed mild hypocellularity with increased number of lymphocytes and relevance of plasmacytoid-lymphocytes. From this study we can conclude that patients with chronic HCV infection are in need for good observation and follow up before taking therapy because they have some hematological abnormalities which need more concern in order to decrease their progressive effect before starting therapy for HCV per se. They should be always screened and given liver and marrow supportive supplements.

It is not clear whether HCV induces an autoimmune disease in infected patients or not. The aim of this study is to evaluate some immunological manifestations in chronic heapatitis C patients and to find out its relationship to liver pathology. The study included 109 positive HCV-RNA patients. They were classified according to liver histopathology into three groups: Group I included 22 patients (G1S1), Group II included 67 patients (G2S2)Group III included 20 patients (G3S3), where G=The degree of necro-inflammatory processS=Stage of liver fibrosis. All patients were investigated for the presence of: cryo-globulin, anti-neutrophil cytoplasmic (ANCA), anti-liver kidney microsomes (LKM), anti-double stranded DNA, (ds-DNA), anti-nuclear (ANA), anti-mitochondrial (AMA) and anti-smooth muscle (ASMA) auto-antibodies. The following results were obtained: ANCA, LKM, ds-DNA, ANA, ASMA, AMA and cryoglobulin were detected in 83/109 (76.1%), 32/109 (29.4%), 23/109 (21.1%), 38/109 (34.9%), 25/109 (22.9%), 5/109 (4.6%) and 60/109 (55%) of chronic HCV respectively. A highly significant positive correlation was found only between ANCA auto-antibodies and cryoglobulin versus grades of liver cirrhosis. Using ANCA, cryoglobulin, age and gender as covariates and by logistic regression analysis, Odds ratio (OR) revealed that these covariates were significant predictors of cirrhosis that add significance to the model according to the sequence: ANCA, cryoglobulin, age and gender suggesting that these covariates associate significantly with development of cirrhosis in HCV patients and that they are significant predictors of liver cirrhosis in HCV patients. The high prevalence of autoantibodies in chronic HCV patients suggests that HCV may trigger an autoimmune reaction, but most probably do not indicate a distinct autoimmune mechanism. Cryoglobulins and ANCA may be a useful prognostic indicator for increased risk of cirrhosis in chronic HCV patients. Follow up studies are recommended.