Association of ficolin-3 with abdominal aortic aneurysm presence and progression.

Essentials Abdominal aortic aneurysm (AAA) is asymptomatic and its evolution unpredictable. To find novel potential biomarkers of AAA, microvesicles are an excellent source of biomarkers. Ficolin-3 is increased in microvesicles obtained from activated platelets and AAA tissue. Increased ficolin-3 plasma levels are associated with AAA presence and progression. SUMMARY: Background Abdominal aortic aneurysm (AAA) patients are usually asymptomatic and AAA evolution is unpredictable. Ficolin-3, mainly synthesized by the liver, is a molecule of the lectin complement-activation pathway involved in AAA pathophysiology. Objectives To define extra-hepatic sources of ficolin-3 in AAA and investigate the role of ficolin-3 as a biomarker of the presence and progression of AAA. Methods Microvesicles (exosomes and microparticles) were isolated from culture-conditioned medium of ADP-activated platelets, as well as from AAA tissue-conditioned medium (thrombus and wall). Ficolin-3 levels were analyzed by western-blot, real-time PCR, immunohistochemistry and ELISA. Results Increased ficolin-3 levels were observed in microvesicles isolated from activated platelets. Similarly, microvesicles released from AAA tissue display increased ficolin-3 levels as compared with those from healthy tissue. Moreover, ficolin-3 mRNA levels in the AAA wall were greatly increased compared with healthy aortic walls. Immunohistochemistry of AAA tissue demonstrated increased ficolin-3, whereas little staining was present in healthy walls. Finally, increased ficolin-3 levels were observed in AAA patients' plasma (n = 478) compared with control plasma (n = 176), which persisted after adjustment for risk factors (adjusted odds ratio [OR], 5.29; 95% confidence interval [CI], 3.27, 8.57)]. Moreover, a positive association of ficolin-3 with aortic diameter (Rho, 0.25) and need for surgical repair was observed, also after adjustment for potential confounding factors (adjusted hazard ratio, 1.55; 95% CI, 1.11, 2.15). Conclusions In addition to its hepatic expression, ficolin-3 may be released into the extracellular medium via microvesicles, by both activated cells and pathological AAA tissue. Ficolin-3 plasma levels are associated with the presence and progression of AAA, suggesting its potential role as a biomarker of AAA.

Protein kinase D1/2 is involved in the maturation of multivesicular bodies and secretion of exosomes in T and B lymphocytes.

Multivesicular bodies (MVBs) are endocytic compartments that enclose intraluminal vesicles (ILVs) formed by inward budding from the limiting membrane of endosomes. In T lymphocytes, these ILV contain Fas ligand (FasL) and are secreted as 'lethal exosomes' following activation-induced fusion of the MVB with the plasma membrane. Diacylglycerol (DAG) and diacylglycerol kinase α (DGKα) regulate MVB maturation and polarized traffic, as well as subsequent secretion of pro-apoptotic exosomes, but the molecular basis underlying these phenomena remains unclear. Here we identify protein kinase D (PKD) family members as DAG effectors involved in MVB genesis and secretion. We show that the inducible secretion of exosomes is enhanced when a constitutively active PKD1 mutant is expressed in T lymphocytes, whereas exosome secretion is impaired in PKD2-deficient mouse T lymphoblasts and in PKD1/3-null B cells. Analysis of PKD2-deficient T lymphoblasts showed the presence of large, immature MVB-like vesicles and demonstrated defects in cytotoxic activity and in activation-induced cell death. Using pharmacological and genetic tools, we show that DGKα regulates PKD1/2 subcellular localization and activation. Our studies demonstrate that PKD1/2 is a key regulator of MVB maturation and exosome secretion, and constitutes a mediator of the DGKα effect on MVB secretory traffic.

Diacylglycerol kinase α regulates the formation and polarisation of mature multivesicular bodies involved in the secretion of Fas ligand-containing exosomes in T lymphocytes.

Multivesicular bodies (MVBs) are endocytic compartments that contain intraluminal vesicles formed by inward budding from the limiting membrane of endosomes. In T lymphocytes, these vesicles contain pro-apoptotic Fas ligand (FasL), which may be secreted as 'lethal exosomes' upon fusion of MVBs with the plasma membrane. Diacylglycerol kinase α (DGKα) regulate the secretion of exosomes, but it is unclear how this control is mediated. T-lymphocyte activation increases the number of MVBs that contain FasL. DGKα is recruited to MVBs and to exosomes in which it has a double function. DGKα kinase activity exerts a negative role in the formation of mature MVBs, as we demonstrate by the use of an inhibitor. Downmodulation of DGKα protein resulted in inhibition of both the polarisation of MVBs towards immune synapse and exosome secretion. The subcellular location of DGKα together with its complex role in the formation and polarised traffic of MVBs support the notion that DGKα is a key regulator of the polarised secretion of exosomes.

Ten year incidence of HCV infection in northern Italy and frequency of spontaneous viral clearance.

BACKGROUND: Little is known of the incidence of hepatitis C virus (HCV) infection, and the frequency of spontaneous viral clearance in the general population is unknown. We conducted an epidemiological study in two Apennine towns in northern Italy. METHODS: Anti-HCV (ELISA and RIBA third generation) and HCV-RNA by polymerase chain reaction were tested in thawed sera from an adult general population of Loiano-Monghidoro in 1986 and 1996, obtained in the context of the MICOL (Multicenter Italian Study on Cholelithiasis). In 1999, anti-HCV positive subjects and sex and age matched controls were recalled in order to identify risk factors for acquiring HCV infection and to assess the family composition of anti-HCV+ subjects. RESULTS: For 1646 subjects, sera were available from both 1986 and 1996 (mean age in 1986 43 (0.39) years). In 1986, 57 (3.46%) subjects were HCV antibody positive (HCV-Ab+). Eight new cases were recorded in 1996: adult incidence was 50.3 cases/100 000 inhabitants/year. Fifty three of 63 (84.1%) HCV-Ab+ sera were also HCV-RNA+. Genotype 2a/2c accounted for 44% and 1b for 47.0% of cases. HCV-Ab+ subjects had higher serum levels of alanine aminotransferase with respect to controls (p<0.005), as did subjects infected with genotype 1 with respect to those with genotype 2 (p<0.05). Eleven of 65 (16.9%) HCV-Ab+ subjects spontaneously cleared HCV-Ab; 7/11 also lost HCV-RNA- in both serum and leucocytes. Sixteen anti-HCV+ subjects belonged to families containing more than one infected member. Married couples accounted for 10 of these 16 subjects. In four of these five married couples, HCV genotype was identical in the two spouses. CONCLUSIONS: In rural northern Italy, the adult incidence of HCV is approximately 50 cases/100 000 inhabitants/year. Our findings suggest that as many as 17% of infected subjects may spontaneously clear HCV-Ab. Interfamilial transmission seems to have a role in the spread of infection.

Improved liver tests and greater biliary enrichment with high dose ursodeoxycholic acid in early stage primary biliary cirrhosis.

BACKGROUND: Ursodeoxycholic acid is currently used for the treatment of primary biliary cirrhosis at 13-15 mg/kg/day, but liver tests of some patients do not return to normal at this dose. Studies reported here were designed to test whether a higher dose of ursodeoxycholic acid than is currently used would induce still greater biliary enrichment of ursodeoxycholic acid and whether such enrichment would lead to still further improvement in liver tests in patients with early primary biliary cirrhosis. METHODS: A total of 20 patients with histologically proven primary biliary cirrhosis were enrolled. Patients had early stage primary biliary cirrhosis as serum bilirubin levels were normal and the Mayo risk score 4.2 +/- 0.5. Group 1 received 600, 1200 and 1800 mg/day of ursodeoxycholic acid; group 2 received 900, 1500 and 2100 mg/day. The order of periods was randomized. Each treatment period lasted 3 months followed by a further 3 months during which a standard dose of ursodeoxycholic acid was given. At the end of each treatment period, liver tests were evaluated, and biliary bile acid pattern of duodenal bile was determined using high pressure liquid chromatography. RESULTS: Biliary bile acid became enriched in ursodeoxycholic acid in direct relationship to dosage [r = 0.84, p < 0.001). At doses of 1800 mg/day (25-35 mg/kg/day), biliary ursodeoxycholic acid averaged 69 +/- 6.6%. A progressive decrease of alanine aminotransferase [p < 0.0001), aspartate aminotransferase [p < 0.001) and alkaline phosphatase [p < 0.02) was observed with increasing concentrations of ursodeoxycholic acid in bile. Biochemical liver tests showed a stronger correlation with biliary concentrations of ursodeoxycholic acid than with the administered dose. CONCLUSIONS: In early primary biliary cirrhosis, higher dose ursodeoxycholic acid appears to be more effective than doses currently recommended.

Molecular analysis of p53 tumor-suppressor gene and microsatellites in preneoplastic and neoplastic lesions of the colon and esophagus.

Mutations in exons 4-8 of the p53 gene by the PCR-SSCP analysis in preneoplastic and neoplastic lesions of the colon (n=11) and esophagus (n=18) were screened. p53 overexpression by immunohistochemistry in 11 colonic lesions and 13 microsatellites, in all the patients (n=29), were also studied. A positive result concordancy between the three techniques was found in 1 adenoma and 2 adenocarcinomas of the colon, each with loss of heterozygocity of microsatellites. Metaplastic lesions of esophagus showed biallelic mutations and low frequency of microsatellite alterations. The relationship between genetic alterations in p53, microsatellites and type of colon and esophageal lesions is discussed.

Efficacy of ursodeoxycholic acid in association with alpha-interferon for chronic hepatitis C in alpha-interferon non-responder patients.

BACKGROUND: The aim of the present study was to evaluate the effect of combined treatment with alpha-interferon (alpha-IFN) and ursodeoxycholic acid (UDCA) on liver function tests and serum HCV-RNA in patients with chronic hepatitis C who had not responded to alpha-IFN alone. METHOD: One hundred and three patients (60 men, 43 women, mean age 49 +/- 1.3 years) who had not responded (both HCV-RNA positive and increased serum ALT levels) to 4 consecutive months of treatment with alpha-IFN (3 MU three times weekly) were randomly assigned to receive UDCA (IFN-UDCA, 53 patients, 600 mg/day) in addition to the same alpha-IFN dose, or to continue alpha-IFN alone (IFN-controls, 50 patients). After stopping alpha-IFN, patients who had received UDCA continued to receive UDCA for an additional 6-month period. The two groups were comparable for sex, basal ALT, basal yGT, genotype distribution and liver histology, while mean age was lower in controls (53 +/- 1.8 vs 46 +/- 1.8 years; P< 0.01). RESULTS: Twenty (38%) out of 53 IFN-UDCA patients had normal ALT, compared with only six (12%) out of 50 IFN-control patients (P < 0.01). HCV-RNA became undetectable in four IFN-UDCA patients. Three months after withdrawal of alpha IFN, 15 IFN-UDCA responders, but none of the IFN-controls, had normal ALT values (P< 0.01); 6 months after withdrawal, nine IFN-UDCA responders still had normal ALT (P= NS) and HCV-RNA was still undetectable in four of them. Portal and periportal inflammation showed a statistically significant improvement (Fisher's exact test P< 0.01) in IFN-UDCA patients as compared with IFN-controls, while no effect was observed on portal fibrosis. CONCLUSIONS: These data demonstrate that UDCA improves the response rate to alpha-IFN. Furthermore, in 8% of IFN-UDCA patients the response rate was sustained and associated with HCV-RNA clearance.

Sluggish small bowel motility is involved in determining increased biliary deoxycholic acid in cholesterol gallstone patients.

OBJECTIVE: Our aim was to establish whether small intestine transit time is defective in subjects with cholesterol gallstones. METHODS: We enrolled 10 patients (eight women, two men; mean age, 48.7 yr; mean body mass index [BMI], 22.4 Kg/m2) with recently diagnosed cholelithiasis, with no liver pathology, who were not taking any drugs, and 11 comparable healthy volunteers (eight women, three men; mean age, 46.2 yr; mean BMI, 22.7 Kg/m2), who served as controls. All subjects underwent orocecal (by starch breath test technique and serum assays of salazopyrin), oroileal (by serum assays of tauroursodeoxycholic acid), and duodenoileal (by serum assays of taurocholic acid) transit times; cholesterol saturation index; and bile acid composition and gallbladder motility studies (by ultrasound). For serum assays, blood samples were collected over a period of 7 h. Gallbladder motility and orocecal transit time were evaluated simultaneously. RESULTS: All four means of assessing transit time gave longer times in cholesterol gallstone patients than in controls: orocecal transit time (salazopyrin) = 366 +/- 13 vs 258 +/- 16 min, p < 0.0005; orocecal transit time (starch breath test) = 415 +/- 139 vs 290 +/- 15 min, p < 0.01; duodenoileal transit time: 272 +/- 23 vs 205 +/- 23 min, p < 0.03; and oroileal transit time: 308 +/- 18 vs 230 +/- 19 min, p < 0.009. Cholesterol gallstone patients showed an increase in percent molar biliary deoxycholic acid (30% +/- 4.5% vs 16% +/- 1.3%, p < 0.02) and a decrease in percent molar cholic acid 32% +/- 2.2% vs 40% +/- 1.3%, p < 0.03) and chenodeoxycholic acid (34% +/- 3% vs 41% +/- 1.8%, p < 0.03), compared with controls; patients also had greater percent molar biliary cholesterol. A linear relationship (r2 = 0.6324, p = 0.0012) between biliary deoxycholic acid and small bowel transit time was found. Residual gallbladder volumes were larger in cholesterol gallstone patients (11.38 +/- 1.27 vs 7.55 +/- 0.39 ml, p < 0.04), whereas basal gallbladder volumes, although higher, did not reach statistical significance (24.25 +/- 2.41 vs 19.98 +/- 1.63 ml; p = ns). CONCLUSIONS: This study confirms that patients with cholesterol gallstones have delayed small bowel transit, defective gallbladder motor function, and increased biliary deoxycholic acid. Delayed small bowel transit may contribute to supersaturation of bile with cholesterol by increasing deoxycholic acid production.

Evidence of exercise-induced myocardial ischemia in patients with primary aldosteronism: the Cross-sectional Primary Aldosteronism and Heart Italian Multicenter Study.

BACKGROUND: Primary aldosteronism (PA) is a disease associated with hypersecretion of aldosterone caused by an aldosterone-producing adrenal adenoma, bilateral adrenal hyperplasia, and, although rarely, by adrenal carcinoma. Arterial hypertension induces several cardiovascular alterations that yield a high cardiovascular risk. It has been shown that reduced myocardial perfusion at rest, assessed by thallium-201 myocardial scintigraphy, was greater in PA than in essential hypertension (EH). However, it is still unknown whether reduced myocardial perfusion at rest and/or regional function abnormalities are present during exercise-induced myocardial stress. PURPOSE: We addressed the impact of PA on myocardial ischemia and sought to identify signs of exercise-induced myocardial ischemia (assessed by MIBI-SPECT and echocardiography) in patients with PA compared to patients with EH. Patients with consistent signs of myocardial ischemia on all of the tests were studied by coronary arteriography. PATIENTS: We studied 72 patients with PA and an age/sex-matched group of 72 patients with EH enrolled in the cross-sectional Primary Aldosteronism and Heart Italian Multicenter Study (PAHIMS). METHODS: Regional function was detected from echocardiographic measurement of wall motion done at baseline and immediately after exercise. Myocardial perfusion was evaluated by SPECT imaging after injecting 99mTc-MIBI with the same-day protocol using the rest-stress sequence. RESULTS: Although the conditions of arterial pressure, duration of hypertension, and target organ damage were equivalent, the patients with PA had greater incidence of both reversible perfusion defects and abnormalities of regional function. Moreover, multiple regression analysis showed that the high plasma aldosterone level was highly predictive for SPECT ischemic score and wall motion index, suggesting that PA contributes to cardiovascular risk over and above that associated with ventricular hypertrophy. Exercise-induced myocardial ischemia in PA was not segmental but widely distributed suggesting that this phenomenon was not related to abnormal coronary perfusion. Accordingly, of the 38 patients with PA who underwent coronarography, there was no presence of significant coronary atherosclerotic lesions in 30 (78.9%) of the patients. CONCLUSIONS: The PAHIMS observed more exercise-induced moderate myocardial ischemic defects (co-detected by SPECT and echocardiograms and not segmental but widely allocated) in patients with PA than in patients with EH. This phenomenon occurred in a greater percentage of patients with PA without significant coronary lesions (78.95%, n = 38), which supports the possible presence of small-vessel intramyocardial disease.

Methylprednisolone administration in primary biliary cirrhosis increases cholic acid turnover, synthesis, and deoxycholate concentration in bile.

As immunosuppressive agents, corticosteroids may be considered an appropriate treatment for primary biliary cirrhosis, even if bone loss and other side effects may occur. We studied biliary lipid metabolism in 10 nonicteric patients, with histologically proven primary biliary cirrhosis (stage I-IV). We administered methylprednisolone (24 mg daily) for 30 days to ascertain its effects on biliary lipid metabolism, which are largely still unknown. All patients underwent a 30-day drug-washout period before entering the trial. The following parameters were studied before and after methylprednisolone treatment: serum biochemistry; cholic acid pool size, kinetics and synthesis; biliary lipid secretion; biliary bile acid pattern; biliary lipid molar percentage; and cholesterol saturation index. Methylprednisolone induced a statistically significant (Wilcoxon rank test) increase in cholic acid turnover (from 0.26+/-0.04 to 0.50+/-0.05 K/day, P = 0.005) and synthesis (from 0.42+/-0.12 to 0.78+/-0.11 mmol/day, P = 0.04), and in bile deoxycholic acid molar percentage (from 19.4+/-2.7 to 30.6+/-4.4% molar, P = 0.01). On the other hand, a significant decrease in biliary cholesterol molar percentage (from 7.9+/-0.7 to 6.4+/-0.5% molar, P = 0.005), cholesterol saturation index (from 1.11+/-0.11 to 0.95+/-0.07, P = 0.05), and biliary cholesterol secretion (from 64.7+/-5.4 to 53.0+/-4.5 micromol/hr, P = 0.005) was observed. These findings show that short-term administration of methylprednisolone in patients with primary biliary cirrhosis does not induce expansion of the cholic acid pool but increases cholic acid synthesis and turnover, as well as intestinal production of deoxycholic acid. If long-term treatment is considered, the beneficial immunosuppressive effects of corticosteroids have to be weighed against the hepatotoxic properties of deoxycholic acid.