Tauroursodeoxycholic acid administration as adjuvant therapy in cirrhotic patients on transplantation waiting lists

BACKGROUND/AIMS

The lack of organ availability and an increased number of end-stage cirrhotic patients has led to the lengthening of liver transplantation waiting lists. The progressive worsening of clinical and functional performance in patients awaiting the graft is one of the factors implicated in the increased mortality during the wait and in poor transplantation outcome. In this work our aim was to evaluate the effects of tauroursodeoxycholic acid administration on biochemical, clinical and functional parameters in a group of cirrhotic patients consecutively placed onto our liver transplantation waiting list.

METHODOLOGY

Ten cirrhotic patients underwent biochemical, clinical and functional evaluation at the time of entering on our liver transplantation waiting list, then tauroursodeoxycholic acid was administered until liver transplantation. Complete evaluation was repeated every 2 months. The results were compared to those of a comparable historical control group that had undergone liver transplantation the year before the study.

RESULTS

All patients were transplanted within 6 months from insertion on the waiting list. Longitudinal analysis of the treated group showed that cholestasis and cytolisis parameters constantly decreased and that gamma-glutamyl transpeptidase was significantly lower compared to baseline values at the 4th month of therapy. Clinical and functional parameters remained stable during follow-up. Comparison with the control group showed that gamma-glutamyl transpeptidase, alkaline phosphatase and both aminotransferases were reduced at the 4th month of therapy. Fewer days of hospital stay and less intensive care were required in the treated group.

CONCLUSIONS

Treatment of end-stage cirrhotic patients awaiting liver transplantation with tauroursodeoxycholic acid improves biochemical parameters of cytolisis and cholestasis, and furthermore helps to maintain clinical and functional stability during the wait. Improved biochemical conditions and steady clinical-functional performance may promote better short-term transplant outcome.

Serum leptin levels in patients with viral chronic hepatitis or liver cirrhosis

BACKGROUND/AIM

Serum levels of leptin, the adipocyte-derived hormone regulating food intake and energy expenditure in mammals, have been found to be increased in cirrhotic patients. The aim of the present study was to investigate leptin serum level in relation to anthropometric features and liver function in patients with viral chronic hepatitis or liver cirrhosis.

METHODS

Serum leptin levels were determined by radioimmunoassay in 30 male and 10 female patients with chronic hepatitis, in 42 male and 10 female patients with liver cirrhosis, and in four respective control groups. Liver function was evaluated by the monoethylglycinexylidide formation test. Body mass index and body fat mass were estimated by weight, height and skinfold thickness measurements.

RESULTS

Compared with controls, absolute serum leptin levels were significantly (p<0.01) lower in chronic hepatitis patients and similar in cirrhotic patients. Leptin serum levels were significantly (p<0.05) higher in cirrhotic than in chronic hepatitis patients. When expressed in relation to body fat mass, the above differences persisted; however, cirrhotic females showed significantly (p<0.05) higher serum leptin values than controls. Serum leptin values correlated negatively (p<0.01) with monoethylglycinexylidide serum values in all groups of patients.

CONCLUSIONS

In patients with chronic viral liver disease, serum leptin levels tend to increase as liver function worsens. This may reflect a decline in the ability to downregulate energy expenditure as an adaptation to anorexia and/or to defective substrate utilisation due to liver disease and may negatively influence body weight homeostasis in these patients.

Utility of alpha-glutathione S-transferase assessment in chronic hepatitis C patients with near normal alanine aminotransferase levels

OBJECTIVES

To study whether determining alpha-glutathione S-transferase (alpha-GST) might improve the assessment of chronic hepatitis C (CHC) patients with near normal alanine aminotransferase levels (NNA).

DESIGN AND METHODS

We studied 119 viraemic CHC patients. They were subdivided into two groups according to the pattern of alanine aminotransferase (ALT) alteration, i.e. consistently above (HA) or below (NNA) twice the upper normal value. In these patients we assessed alpha-GST and correlated its levels to clinical, histological, and virological findings, further evaluating whether alpha-GST might improve the assessment of CHC patients with NNA.

RESULTS

alpha-GST showed a significant correlation with aminotransferases, though not with histological necroinflammatory activity and fibrosis or with hepatitis C virus RNA levels. Twenty-seven patients had NNA (23%), and within this subgroup of patients alpha-GST identified a subset of patients with a higher viral load.

CONCLUSIONS

alpha-GST in CHC patients is related to hepatocellular necrosis parameters, but unrelated both to histology and to viraemia. However, in patients with NNA, alpha-GST identified a subgroup of patients with a higher viral load. In this subgroup of patients alpha-GST alteration likely represents the expression of a more severe damage. Because this injury is not detectable by the usual biochemical or histological work-up, we suggest that alpha-GST could a useful tool for monitoring liver damage over time.

Beneficial effects of intracoronary adenosine as an adjunct to primary angioplasty in acute myocardial infarction

BACKGROUND

The benefits of vessel recanalization in acute myocardial infarction (AMI) are limited by reperfusion damage. In animal models, adenosine limits reperfusion injury, reducing infarct size and improving ventricular function. The aim of this study was to evaluate the safety and feasibility of adenosine adjunct to primary PTCA in AMI.

METHODS AND RESULTS

Fifty-four AMI patients undergoing primary PTCA were randomized to intracoronary adenosine or saline. The 2 groups were similar for age, sex, and infarct location. Adenosine administration was feasible and well tolerated. PTCA was successful in all patients and resulted in TIMI 3 flow in all patients given adenosine and in 19 given saline (P<0.05). The no-reflow phenomenon occurred in 1 adenosine patient and in 7 saline patients (P=0.02). Creatine kinase was lower in the adenosine group, and a Q-wave MI developed in 16 adenosine patients and in 23 saline patients (P=0.04). Sixty-four percent of dyssynergic segments improved in the adenosine group and 36% in the saline group (P=0. 001). Function worsened in 2% of dysynergic segments in the adenosine group and in 20% in the saline group (P=0.0001). Adverse cardiac events occurred in 5 patients in the adenosine group and in 13 patients in the saline group (P=0.03).

CONCLUSIONS

Intracoronary adenosine administration is feasible and well tolerated in AMI. Adenosine adjunct to primary PTCA ameliorates flow, prevents the no-reflow phenomenon, improves ventricular function, and is associated with a more favorable clinical course.

Beneficial effects of intracoronary adenosine as an adjunct to primary angioplasty in acute myocardial infarction

BACKGROUND

The benefits of vessel recanalization in acute myocardial infarction (AMI) are limited by reperfusion damage. In animal models, adenosine limits reperfusion injury, reducing infarct size and improving ventricular function. The aim of this study was to evaluate the safety and feasibility of adenosine adjunct to primary PTCA in AMI.

METHODS AND RESULTS

Fifty-four AMI patients undergoing primary PTCA were randomized to intracoronary adenosine or saline. The 2 groups were similar for age, sex, and infarct location. Adenosine administration was feasible and well tolerated. PTCA was successful in all patients and resulted in TIMI 3 flow in all patients given adenosine and in 19 given saline (P<0.05). The no-reflow phenomenon occurred in 1 adenosine patient and in 7 saline patients (P=0.02). Creatine kinase was lower in the adenosine group, and a Q-wave MI developed in 16 adenosine patients and in 23 saline patients (P=0.04). Sixty-four percent of dyssynergic segments improved in the adenosine group and 36% in the saline group (P=0. 001). Function worsened in 2% of dysynergic segments in the adenosine group and in 20% in the saline group (P=0.0001). Adverse cardiac events occurred in 5 patients in the adenosine group and in 13 patients in the saline group (P=0.03).

CONCLUSIONS

Intracoronary adenosine administration is feasible and well tolerated in AMI. Adenosine adjunct to primary PTCA ameliorates flow, prevents the no-reflow phenomenon, improves ventricular function, and is associated with a more favorable clinical course.

Effects of intracavernous administration of selective antagonists of alpha(1)-adrenoceptor subtypes on erection in anesthetized rats and dogs

The proerectile properties of three novel alpha(1)-adrenoceptor (alpha(1)-ADR) antagonists with different profiles of selectivity for the alpha(1)-ADR subtypes have been evaluated in anesthetized rats and dogs on intracavernous (IC) injection, in comparison with prazosin and phentolamine. In rats, the tested compounds decreased blood pressure (BP) and increased IC pressure (ICP), as well as the ratio ICP/BP. Rec 15/2841 (alpha(1a)- plus alpha(1L)-ADR-selective antagonist) and Rec 15/2615 (alpha(1b)-ADR selective) were the most potent compounds. The ICP/BP ratios calculated after injection of Rec 15/3039 (alpha(1d)-ADR selective) were not markedly different from those observed after vehicle injection. Prazosin and phentolamine proved poorly active, their main effect being hypotension. Approximate ED(25) values (dose of compound in micrograms inducing 25% increase of ICP/BP ratio) were Rec 15/2615 (22 microgram/kg)>= Rec 15/2841 (29 microgram/kg) > prazosin (136 microgram/kg) > phentolamine (1298 microgram/kg) > Rec 15/3039 (9600 microgram/kg). Submaximal stimulation of the cavernous nerve elicited an ICP rise whose amplitude was not altered by Rec compounds. In contrast, prazosin and phentolamine decreased this ICP rise. All compounds but 15/3039 induced significant increase of the ICP/BP ratio in dogs. Rec 15/2615 proved to be the most interesting compound, inducing significant increases of ICP/BP at doses practically devoid of effects on BP. The rank order of potency in dog in increasing the ICP/BP ratio was similar to that observed in rats. Only at the highest doses tested, all compounds, except Rec 15/3039, decreased the ICP rise elicited by submaximal stimulation of the cavernous nerve. Our data demonstrate that the alpha(1b)- and alpha(1L)-ADR subtypes are functionally relevant for the erectile function in these models, and that alpha(1b)- and/or alpha(1L)-ADR subtypes selective antagonists could represent a real advantage in erectile dysfunction therapy.

Effect of calcium antagonists on glomerular arterioles in spontaneously hypertensive rats

Through the use of microanatomic techniques, we investigated the effects of treatment with some dihydropyridine-type calcium antagonists (CAs) (ie, lercanidipine, manidipine, and nicardipine) and with the nondihydropyridine-type vasodilator hydralazine on hypertension-dependent glomerular injury and on the morphology of afferent and efferent arterioles in spontaneously hypertensive rats (SHR). Fourteen-week-old male SHR and age-matched normotensive Wistar-Kyoto rats were left untreated (control groups). Four additional groups of 14-week-old SHR were treated for 12 weeks with daily oral doses of 2.5 mg/kg lercanidipine, 5 mg/kg manidipine, 3 mg/kg nicardipine, or 10 mg/kg hydralazine. These treatments decreased systolic blood pressure values to a similar extent in SHR. Signs of glomerular injury, as characterized by glomerulosclerosis, hypertrophy, and an increased number of mesangial cells, were observed in control SHR. The treatment with CAs improved glomerular morphology and decreased the number of mesangial cells. Lercanidipine and manidipine were more effective than nicardipine in countering glomerular injury. In the SHR, both afferent and efferent arterioles revealed luminal narrowing, accompanied by increased wall thickness in efferent arterioles. The dihydropyridine-type derivatives that were tested decreased the luminal narrowing of afferent arterioles. Lercanidipine and manidipine countered the luminal narrowing of efferent arterioles. Hydralazine had no effect on hypertension-dependent glomerular injury or vascular changes. The present data indicate that lercanidipine and manidipine vasodilate afferent and efferent arterioles in SHR. A vasodilatory activity on efferent arteriole, which is not induced by the majority of CAs, may represent an useful property in the treatment of hypertension complicated by renal disease.

13CO2 excretion in breath of normal subjects and cirrhotic patients after 13C-aminopyrine oral load. Comparison with MEGX test in functional differentiation between chronic hepatitis and liver cirrhosis

BACKGROUND/AIMS

Liver function can be evaluated using 13C breath tests that explore liver Cytochrome P450 activity. Aminopyrine is one of the first compounds used in liver function testing. Lidocaine metabolism to monoethylglycinexylidide is also a valid tool to assess liver function. Although liver Cytochrome P450 metabolizes both compounds, lidocaine metabolism is flow-dependent while aminopyrine metabolism does not depend on liver blood flow.

METHODOLOGY

The 1st part of the study evaluated the appearance and disappearance rate of 13CO2 in the breath of both normal subjects and in cirrhotic patients, so as to establish optimal sampling times and to evaluate the amount of time needed before performing a subsequent breath test. The 2nd part of the study compared the aminopyrine breath test with the monoethylglycinexylidide test in patients with chronic hepatitis or cirrhosis.

RESULTS

Complete 13CO2 disappearance was recorded 24 hours after the test in normal subjects, while it took 3 days to disappear from the breath of cirrhotic patients. Breath sampling at 60, 120 and 180 min were equally valid in differentiating chronic hepatitis from cirrhosis. The aminopyrine breath test and monoethylglycinexylidide test showed a good yet not close correlation.

CONCLUSIONS

This study showed that in cirrhotic patients a 13C breath test can be performed 3 days after the previous one. In chronic hepatitis and cirrhotic patients, the aminopyrine breath test and the monoethylglycinexylidide test evaluated similar, but not identical, hepatic subfunctions, suggesting that multiple 13C breath test using different substrates could explore liver function better.

The rate of plasmin formation after in vitro clotting is inversely related to lipoprotein(a) plasma levels

Lipoprotein(a) levels are largely genetically determined and are linked to increased risk of coronary artery disease. The hypothesis that elevated lipoprotein(a) levels lead to decreased fibrinolysis, due to the close structural homology with plasminogen, could in part explain the genesis of this risk, although contrasting results have been obtained in different studies. The aim of our study was to evaluate whether the rate of plasmin formation, enhanced in vitro by a fixed amount of human tissue plasminogen activator after clotting, was related to plasma lipoprotein(a) levels in 45 healthy subjects. Aliquots of human plasma were clotted with calcium chloride and thrombin followed by addition of tissue plasminogen activator. We then measured the time course of plasmin formation, determined as hydrolysis of H-D-valyl-L-leucyl-L-lysine-p-nitroanilide dihydrocortide (S-2251). The log of lipoprotein(a) level was negatively related to the rate of plasmin formation (r(s)=-0.46, P=0. 002), and multiple regression analysis indicated that this relationship was not influenced by the amount of plasminogen, fibrinogen, plasminogen activator inhibitor-1, tissue plasminogen activator, or by the size of apo(a) isoforms. These data support the concept that lipoprotein(a) can inhibit plasminogen activation and plasmin formation and can thereby play an important role in the genesis of atherosclerosis as an antifibrinolytic agent.

Poorly controlled elderly Type 2 diabetic patients: the effects of increasing sulphonylurea dosages or adding metformin

AIMS

To assess the effects and safety of increasing sulphonylurea dosages or adding metformin in poorly controlled elderly Type 2 diabetic patients.

METHODS

A 18-month multicentre clinical study was performed on sulphonylurea-treated diabetic patients over 70 years of age with well-preserved renal function, steady fasting blood glucose > or = 200 mg/dl and HbA1c > or = 9%. Patients were randomly assigned to sulphonylurea increased up to its maximum dosage (1st group) or to addition of metformin (2nd group). Glycaemic control, lipid pattern, haemostatic status and safety were monitored during run-in, at baseline and at scheduled intervals for 18 months. Results refer to 85 patients in the 1st group and 89 patients in the 2nd with complete data.

RESULTS

Similar improvements in glycaemic levels were observed with both treatments within the first month and a similar decrease in HbA1c within the third month. No further changes occurred in glycaemic control. In the 1st group, fasting glucose (mmol/l, mean +/- SE) decreased from 14.21 +/- 0.49 to 9.88 +/- 0.21, average day-long glucose from 14.87 +/- 0.27 to 10.69 +/- 0.19 and HbAt1c(%) from 10.32 +/- 0.13 to 8.66 +/- 0.13. In the 2nd treatment group fasting glucose decreased from 14.59 +/- 0.61 to 9.05 +/- 37.28, average day-long glucose from 15.09 +/- 0.29 to 10.32 +/- 0.21 and HbA1c from 10.33 +/- 0.13 to 8.77+/-0.12 (for all P<0.0005). In this 2nd group, a decrease in LDL-cholesterol (P < 0.05) and an increase in HDL-cholesterol levels (P < 0.02) were also observed. In the 1st group, anthrombin III activity increased significantly (P<0.01). In the 2nd group, significant reductions in markers of platelet function (FP4 and betaTG, P < 0.01), thrombin generation (FPA, F1 + 2 and D-D, P<0.01), and fibrinolysis inhibition (PAI-1 activity, PAI-1 antigen, P< 0.001) were observed. Increases in some fibrinolytic activation markers (t-PA activity, and AT-III activity, P<0.01) occurred. Fasting lactate concentrations were unchanged in the metformin-treated group. No serious adverse effects were observed in either group.

CONCLUSIONS

These results suggest that either high sulphonylurea dosages or a therapy combining lower sulphonylurea dosages with metformin are effective and safe in an aged but healthy population. Metformin provides additional benefits counteracting several cardiovascular risk factors but must be administered with caution, bearing in mind the general contra-indications for the drug but not age alone.

A strong inverse relationship between PAI-1 and Lp(a) in hypertensive Type 2 diabetic patients

Thrombophilia with a contemporary reduction of fibrinolytic activity has been observed both in diabetes mellitus and hypertension. Previously, we found a relationship between plasminogen activator inhibitor Type 1 (PAI-1) and lipoprotein(a) [Lp(a)] in Type 2 diabetes mellitus patients without complications. We hypothesised that this relationship could be due to a compensatory mechanism able to lower the risk of hypofibrinolysis as found in Type 2 diabetes mellitus. The present work was aimed at investigating the influence of concurrent hypertension and diabetes mellitus on the plasma levels of these two fibrinolytic inhibitors. In addition, other risk factors, known to influence the fibrinolytic parameters, were taken into account. Forty-nine Type 2 nonhypertensive diabetic patients without complications, 47 Type 2 hypertensive diabetic patients without complications, 54 non-diabetic hypertensive subjects without complications as well as 87 control subjects were studied. Plasma concentrations of Lp(a), PAI-1 antigen and activity, and the main parameters of oxidative, lipo- and glycometabolic balance were determined. Significant statistical differences between diabetic and non-diabetic subjects were found concerning triglycerides and antioxidant defence (p<0.01). Analysis of variance showed the F test statistically significant in evaluating the Log PAI-1/Lp(a) (p = 0.02). Correlation analysis between Log PAI-1 antigen and Lp(a) was significant in non-hypertensive diabetic patients, as expected (r = -0.38, p<0.01), and even stronger in hypertensive diabetic patients (r = -O.72,p<0.01). These results allow to hypothesise that the relationship between PAI-1/Lp(a) could be determinant in avoiding vascular complications due to diabetes mellitus and hypertension.

Steatosis and bile duct damage in chronic hepatitis C: distribution and relationships in a group of Northern Italian patients

BACKGROUND/AIMS

Hepatitis C virus (HCV) related disease follows a long, benign course and most affected patients have mild disease. Liver biopsy is mandatory to grade and stage the disease. Characteristic, though non-specific, HCV histological lesions such as bile duct damage and steatosis have been singled out but their association with non-histological parameters has not been completely defined. Our aim was to study the relationships among these histological lesions and clinical, biochemical, functional and virological characteristics in a group of Northern Italian patients with chronic hepatitis.

METHODS

We studied 172 patients with HCV-related chronic hepatitis. Patients were divided into groups on the basis of histology including bile duct damage and steatosis. Clinical, biochemical, functional and virological profiles were related to histological findings.

RESULTS

Histological grading and staging of disease increased as the age of patients increased. Steatosis was present in 70% of our patients and was related to a higher degree of fibrosis and to decreased functional activity. The prevalence of bile duct damage was 20%. This lesion was present in older patients with higher staging and impaired liver function. Biochemically it was associated with an increase in aspartate aminotransferase, gammaglutamyltranspeptidase, alkaline phosphatase, and total bilirubin.

CONCLUSIONS

In the population we studied, HCV chronic hepatitis was predominantly a mild disease. Moreover both steatosis and bile duct damage were also mild. Steatosis was associated with fibrosis and this might influence liver metabolic function. Bile duct lesions were found in older patients with advanced disease showing biochemical evidence ofcholestasis. The molecular role HCV might play in the pathogenesis of these histological features should be addressed in further studies.

Effect of several 5-hydroxytryptamine(1A) receptor ligands on the micturition reflex in rats: comparison with WAY 100635

Several novel N-arylpiperazine derivatives were synthesized and tested for their 1) affinity and functional activity on 5-hydroxytryptamine(1A) (5-HT(1A)) receptors in vitro; 2) activity in models predictive of antagonism at somatodendritic and postsynaptic 5-HT(1A) receptors; and 3) effects on the micturition reflex in anesthetized and conscious rats. These studies also included 1-(2-methoxyphenyl)-4-[4-(2-phthalimido)butyl] piperazine hydrobromide (NAN 190), 8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-8-azaspiro[4, 5]decane-7,9-dione dihydrochloride (BMY 7378), and N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl-N-(2-pyridinyl)cyclohex anecarboxamide (WAY 100635). Almost all compounds were found to be potent and selective for the human recombinant 5-HT(1A) receptor, with K(i) values in the nanomolar range. [(35)S]GTPgammaS binding in HeLa cells expressing the recombinant human 5-HT(1A) receptor allowed classification of the compounds into neutral antagonists and partial agonists. Almost all neutral antagonists were active in blocking 8-hydroxy-2-dipropylaminotetralin (8-OH-DPAT)-induced forepaw treading in rats (postsynaptic model) and hypothermia in mice (somatodendritic model) with the same potency, whereas compounds showing partial agonistic activity were active in the postsynaptic model but were inactive, or poorly active, in the somatodendritic model. Neutral antagonists potently inhibited volume-induced bladder-voiding contractions in anesthetized rats. Contractions were completely blocked, and the disappearance of bladder contractions lasted 7 to 13 min after the highest doses tested. Furthermore, neutral antagonists increased bladder volume capacity in conscious rats during continuous transvesical cystometry, whereas micturition pressure was only slightly, and not dose-dependently, reduced. Partial agonists were inactive or poorly active, inducing a disappearance time of bladder contractions that did not exceed 6 min in anesthetized rats, and failing to increase bladder volume capacity in conscious rats. These findings indicate that only neutral 5-HT(1A) receptor antagonists are endowed with inhibitory effects on the bladder.

Microchimerism and blocking activity in women with recurrent spontaneous abortion (RSA) after alloimmunization with the partner's lymphocytes

Alloimmunization therapy using the partner's leukocytes has been reported to be effective in preventing the failure of pregnancy in patients who have suffered RSA of unknown cause. After alloimmunization, several investigators have reported the presence of blocking factors (BF) in women with successful pregnancies in in vitro assays of lymphocyte response. The recent discovery of small numbers of ubiquitous donor cells (microchimerism) in human transplants up to 29 years post-transplantation has raised questions about the migration of the chimeric cells and their role in the induction and perpetuation of tolerance. We have investigated the production of BF in the mixed lymphocyte reaction (MLR) before and in some patients after alloimmunization and its possible relation with the development of microchimerism (M). Before the treatment we studied 14 couples with three or more abortions who were evaluated clinically to rule-out genetic, structural, endocrine, infectious and autoimmune causes. The M study was done by nested PCR-SSP technique with HLA-DR alleles, before and after 30 days of the last immunization. Before the treatment only one patient was M positive and none were BF positive with inhibition effect (IE) > 50. Only eight underwent treatment. The patients had between three and nine alloimmunizations (x = 4.7). After treatment, all patients were M positive with IE > 50. Six months after the last immunization, four patients are M positive with IE > 50. In conclusion, the hypothesis proposes that alloimmunization establishes a state of microchimerism that would be the necessary allogeneic stimulus for T-cell activation, and the induction or maintenance of tolerance to the fetus during pregnancy. reserved.

Leptin levels in nonalcoholic steatohepatitis and chronic hepatitis C

BACKGROUND/AIMS

Leptin is a peptide which regulates food intake and energy expenditure. Moreover, it is involved in the homeostasis of body composition and is linked to the regulation of insulin signaling, thus playing an important role in liver fat storage. Steatosis is a common finding in chronic hepatitis C, and both viral and metabolic factors have been suggested to explain the presence of this histological characteristic. In order to study leptin in chronic liver disease characterized by the presence of steatosis, we evaluated its serum levels in patients with nonalcoholic steatohepatitis (NASH), in chronic hepatitis C (CHC) patients with no histological findings of steatosis, and CHC patients with steatosis but no risk factors for its development.

METHODOLOGY

We studied 6 male patients with NASH whose diagnosis was made on the basis of histological findings and clinical criteria. From among a cohort of 170 CHC patients we put together 2 groups of 6 male patients each (with or without steatosis at liver biopsy examination), who had no risk factors for NASH. Male patients were chosen in order to avoid gender influence on leptin levels. Further criteria for admission were similar impairment of liver metabolic function as assessed by the monoethylglycinexylidide (MEGX) test and, in patients with CHC, similar body mass index (BMI) and histological staging. Moreover, we evaluated leptin/BMI ratio, in order to rule out BMI influence on leptin levels. Leptin levels were assessed by means of radioimmunoassay.

RESULTS

We found that BMI was higher in NASH compared to CHC (27.2 +/- 2.9 vs. 23.9 +/- 1.8; p = 0.01). Analysis of serum leptin levels showed an increasing trend starting from patients with CHC without steatosis (3.2 +/- 0.4 ng/ml), through CHC patients with steatosis (4.2 +/- 0.7 ng/ml) up to patients with NASH (5.7 +/- 2 ng/ml), although the differences observed were not statistically significant. Moreover, the ratio of leptin to BMI also followed the same trend showing increasing values (CHC without steatosis = 0.04 +/- 0.02; CHC patients with steatosis = 0.17 +/- 0.03; NASH = 0.203 +/- 0.07). Leptin levels and BMI showed a significant relationship (n = 18; r = 0.60; p < 0.01).

CONCLUSIONS

The increasing trend observed in leptin serum levels among the different groups of patients showed that in chronic liver disease characterized by the presence of steatosis, leptin signaling is preserved. Moreover, CHC factors different from the metabolic ones should be investigated in order to explain the presence of steatosis. Further studies on broader groups of patients are needed to verify these preliminary results.

Vascular-selective effect of lercanidipine and other 1,4-dihydropyridines in isolated rabbit tissues

The aim of this study was to characterize the in-vitro vasoselectivity of lercanidipine (in comparison with lacidipine, amlodipine, nitrendipine and felodipine) by evaluating its functional calcium antagonistic activity on rabbit vascular (aorta) and cardiac tissues (heart ventricle). Although incubation with all the compounds tested elicited a concentration-dependent relaxant effect on vascular tissue precontracted with KCl (80 mM), 50% relaxation was reached at different times for each concentration and drug tested. At 10 nM concentration 50% relaxation was reached after 210 min with lercanidipine, 278 min with amlodipine, 135 min with lacidipine, 75 min with nitrendipine and 70 min with felodipine. The onset of the effect was, therefore, similar for lercanidipine, amlodipine and lacidipine, but faster for nitrendipine and felodipine. Similarly, all the compounds tested concentration-dependently reduced the force of cardiac contraction (negative inotropic activity). In this model, the time needed to reach 50% reduction in contractile force was also concentration-dependent, and the ranking order of the speed of onset of the effect (evaluated as the ratio of the IC50 values (the concentrations inhibiting contraction by 50%) calculated after 1 and 4 h incubation) was lacidipine (3.8) > amlodipine (9.6) > felodipine (39) > lercanidipine (68) = nitrendipine (89). The vasoselectivity, expressed as the ratio of the IC50 values obtained on cardiac and vascular tissue, were (for 4 h incubation) 730, 193, 95, 6 and 3 for lercanidipine, lacidipine, amlodipine, felodipine and nitrendipine, respectively, showing that lercanidipine is the most vasoselective of the calcium-antagonists tested. The results show that lercanidipine reduces the inotropic force of the rabbit heart to a lesser extent than do other calcium antagonists, and that this drug had the best heart/vessel selectivity index among the compounds tested at all the times tested.

Progressive liver functional impairment is associated with an increase in AST/ALT ratio

The ratio of serum aspartate aminotransferase to alanine aminotransferase (AST/ALT ratio) has been proposed as a noninvasive method of assessing liver fibrosis and cirrhosis. Our aims were to confirm the usefulness of the AST/ALT ratio in diagnosing cirrhosis noninvasively as well as to verify the existence of a relationship between the ratio and liver functional impairment. In all, 348 patients (177 with chronic hepatitis, 171 with cirrhosis) were retrospectively evaluated and the AST/ALT ratio was related to monoethyl glycine xylidide (MEGX) formation. Moreover, in a subgroup of 54 patients we analyzed the relationships among the AST/ALT ratio and indocyanine green clearance and half-life. The AST/ALT ratio was able to separate patients with mild fibrosis from those with severe fibrosis and cirrhosis. The AST/ALT ratio, MEGX, prothrombin activity, and platelet count were selected by multivariate analysis as variables associated with cirrhosis. The AST/ALT ratio showed significant correlations both with MEGX formation and with indocyanine green clearance and half-life. The alterations of indocyanine green kinetics, which depend upon liver blood flow and uptake, were likely due to progressive fibrosis. These findings might partially explain the increase in the AST/ALT ratio as disease progresses.

Determination of plasma metformin by a new cation-exchange HPLC technique

Metformin is an oral antihyperglycemic agent used in the therapy of noninsulin-dependent diabetic patients. This biguanide can induce dangerous complications such as lactic acidosis when its plasma concentration is too high. For this reason, the determination of plasma metformin should always be done during treatment. We developed a new HPLC method, for the routine determination of plasma metformin, with good reliability, rapid execution, and low costs. Sample preparation involved precipitation of the plasma proteins containing the internal standard buformin with a mixture of methanol, zinc sulfate, and ethylene glycol; the diluted supernatant was injected into a cation-exchange column. The mobile phase was potassium dihydrogenphosphate buffer-containing acetonitrile. The eluent was monitored at 236 nm. The calibration curve is linear within the range of 20-4000 ng/mL; the within-day coefficients of variation were less than 2.2% for metformin and 1.5% for buformin; the day-to-day coefficients of variation were less than 2.5% for metformin and 1.9% for buformin. The mean recoveries obtained from supplemented samples were included between 99.4 and 104.2% for metformin. Many characteristics make this method useful and easily accessible to all clinical laboratories equipped with HPLC instrumentation.

Effects of alpha1-adrenoceptor antagonists on agonist and tilt-induced changes in blood pressure: relationships to uroselectivity

We evaluated the uroselectivity of a series of alpha1-adrenoceptor antagonists by comparing their potency against phenylephrine-induced increases in urethral perfusion pressure and diastolic blood pressure in the anesthetized rabbit and pithed rat. In the rabbit, Rec 15/2739 (N-[3-[4-(2-methoxyphenyl)-1-piperazinyl]propyl]-3-methyl-4-oxo-2-phenyl -4H-1-benzopyran-8-carboxamide) as well as analogs with a chlorine substituent on the methoxyphenyl ring (Rec 15/2869) or this substituent combined with the replacement of the phenyl substituent on the pyran ring by cyclohexyl (Rec 15/3011) were 2-6-fold more potent against the urethral vs. vascular response to phenylephrine. Rec 15/2841 (N-[3-[4-(2-methoxyphenyl)-1-piperazinyl]propyl]-3-methyl-4-oxo-2-cyc lohexy-4H-1-benzopyran-8-carboxamide) was only 1.5-fold more potent against the urethral response. SL 89.0591 and tamsulosin also showed selectivity for the urethral response (2-2.5-fold), while the quinazolines produced equipotent blockade of urethral and vascular responses (selectivity ratio = 0.9-1.1). The urethral selectivities of Rec 15/2739 and its derivatives were confirmed by evaluation of the response to tilt in sedated, hypovolemic rabbits. Phenylephrine challenge assays did not show any of the antagonists, with the exception of terazosin at 300 microg kg(-1), to be uroselective in the rat (selectivity ratios = 0.2-1.5); potentiation of tilt-induced hypotension in the anesthetized rat showed substantial differences from the rabbit, with Rec 15/2739, but not Rec 15/3011 and Rec 15/2841 showing orthostatic effects equivalent to that observed for prazosin. Hence, Rec 15/2739 was uroselective in the rabbit, but not in the rat, while two of its close structural analogs were highly uroselective in both species. An assay for orthostatic activity in the conscious rat yielded different results, showing prazosin and terazosin, but not Rec 15/2739, to cause a reversal of the pressor response to tilt. Hence, the apparent uroselectivity of an alpha1-adrenoceptor antagonist is both species- and assay-dependent.

Probability of non-response during interferon therapy in patients with chronic hepatitis C

BACKGROUND/AIMS

About 50% of patients with chronic hepatitis C do not respond to interferon therapy and this failure is expensive. The aim of this study was to identify possible predictive factors of biochemical non-response during interferon therapy among biochemical, virological (HCV genotype), histological (Knodell's score) and pharmacokinetic (monoethylglycinexylidide formation test) pre-treatment parameters.

METHODOLOGY

Our study included 60 patients with chronic hepatitis C undergoing a course of Interferon therapy. Patients whose serum ALT levels were normal at the 3rd month of therapy and remained so until the end of treatment were regarded as responders.

RESULTS

In univariate analysis, only the gamma-glutamyltransferase (gamma-GT) and the gamma-GT/alanine aminotranferase ratio were significantly higher in non-responder patients. Multivariate logistic analysis showed that high gamma-GT levels, high histological activity index, low monoethylglycinexylidide formation rate and viral genotype 1 were the best combination for the identification of non-responder patients (16.7% error rate). By adding alanine aminotranferase modification at the 1st month of therapy the probability error was reduced to 5%.

CONCLUSIONS

These results show that the combination of biochemical, histological, virological and pharmacokinetic pre-treatment variables, associated with alanine aminotranferase modification at the 1st month of therapy, can predict non-response to interferon and allow therapeutic modifications.

Chronic liver disease related to hepatitis C virus: age of patients seems to be a determinant of severity independently of viral genotype

BACKGROUND

Hepatitis C virus infection accounts for varying severity of chronic liver disease. Clinical manifestations of infection have been related to different virus genotypes, with conflicting results.

DESIGN

We performed a cross-sectional study on a Northern-Italian group of patients with chronic hepatitis, cirrhosis and hepatocellular carcinoma related to hepatitis C virus infection in order to verify the association of different viral strains and the outcomes of viral disease.

METHODS

Two hundred and seventy-one patients referred to our unit for liver disease were studied and clinical, biochemical, histological, and functional parameters were investigated.

RESULTS

Different viral genotypes were not associated with peculiar findings in any of the degrees of liver disease. However, a progressive age increase was associated with disease severity, although clinical and functional staging of cirrhotic patients with hepatocellular carcinoma was better compared to tumour-free cirrhotic patients. There was an increased prevalence of genotype 1b related to the age of the patients. In multivariate regression analysis the patients' age and apparent duration of infection were independently associated with the presence of cirrhosis and only the age of patients was associated to hepatocellular carcinoma.

CONCLUSIONS

In the population we studied age of the patients seemed to be a determinant conditioning disease severity, likely reflecting older infections and long-standing liver disease. The prevalence of certain genotypes in varying degrees of liver disease could be an epiphenomenon which might also be explained by the changing prevalence of infecting strains over the past decades.

Can the MEGX test and serum bile acids improve the prognostic ability of Child-Pugh's score in liver cirrhosis?

BACKGROUND

Liver transplantation is nowadays the therapeutic option for end-stage liver disease. Correct disease staging is the main step towards improving the timing of listing for liver transplantation so as to avoid premature or late entry. The need for correct prognostic evaluation is due to the limited number of donors and to the increasing number of patients awaiting transplantation. Our aim was to verify whether Child-Pugh's score might be improved by adding the monoethylglycinexylidide (MEGX) formation test and/or serum bile acid determination.

METHODS

We evaluated 182 cirrhotic patients (44 Child-Pugh class A, 97 class B, and 41 class C) of mixed aetiology referring to a tertiary care centre for functional staging of liver disease. These patients were prospectively followed-up for 12-72 months. During this period, 45 patients died, 46 received a transplant, and 91 survived without transplantation. The end-point of analysis was either survival or liver disease-related death at the 6th, 12th, 18th and 24th months of follow-up. The 46 transplanted patients were excluded from the study upon transplantation.

RESULTS

In our study, a cut-off for Child-Pugh's score < 8 confirmed its usefulness, especially in short-term prognostic prediction, while mid- and long-term prediction improved by almost 10% by using the combination of a Child- Pugh's score > 8 and an MEGX value < 15 mg/l. Cox's multi-variate regression analysis indicated that MEGX values either with Child-Pugh's score or with prothrombin activity and ascites were independent prognostic variables.

CONCLUSIONS

Besides confirming that Child-Pugh's score as the basis of prognostic evaluation of cirrhotic patients, these results suggest that the MEGX test might be a complement to the original score when a patient is being evaluated for a liver transplantation programme.

Synthesis, pharmacological evaluation, and structure-activity relationship and quantitative structure-activity relationship studies on novel derivatives of 2,4-diamino-6,7-dimethoxyquinazoline alpha1-adrenoceptor antagonists

A new series of novel piperazine and non-piperazine derivatives of 2, 4-diamino-6,7-dimethoxyquinazoline was synthesized and evaluated for binding affinity toward alpha1-adrenergic and other G-protein-coupled aminergic receptors. The alpha1-adrenoceptor (AR) subtype selectivity was also investigated for the most interesting compounds. Only compound 16 showed moderate selectivity toward the alpha1b-AR subtype. Selected compounds were tested in vivo in a dog model indicating activity on blood pressure and on the lower urinary tract. Compound 10 showed in vivo potency close to that of prazosin. Powerful interpretative and predictive theoretical QSAR models have been obtained. The theoretical descriptors employed in the rationalization of the alpha1-adrenergic binding affinity depict the key features for receptor binding which can be summarized in an electrostatic interaction between the protonated amine function and a primary nucleophilic site of the receptor, complemented by short-range attractive (polar and dispersive) and repulsive (steric) intermolecular interactions. Moreover, on predictive grounds, the ad hoc derived size and shape QSAR model developed in a previous paper (Rastelli, G.; et al. J. Mol. Struct. 1991, 251, 307-318) proved to be successful in predicting nanomolar alpha1-adrenergic binding affinity for compound 28.