c-peptide and Liver-Cirrhosis--Alcoholic

Several studies have demonstrated that diabetic patients with cirrhosis require insulin treatment because of insulin resistance. As chronic alcoholic liver damage is partly due to the lipoperoxidation of hepatic cell membranes, anti-oxidizing agents may be useful in treating or preventing damage due to free radicals. The aim of this study was to ascertain whether long-term treatment with silymarin is effective in reducing lipoperoxidation and insulin resistance in diabetic patients with cirrhosis.. A 12-month open, controlled study was conducted in two well-matched groups of insulin-treated diabetics with alcoholic cirrhosis. One group (n=30) received 600 mg silymarin per day plus standard therapy, while the control group (n=30) received standard therapy alone. The efficacy parameters, measured regularly during the study, included fasting blood glucose levels, mean daily blood glucose levels, daily glucosuria levels, glycosylated hemoglobin (HbA1c) and malondialdehyde levels.. There was a significant decrease (p<0.01) in fasting blood glucose levels, mean daily blood glucose levels, daily glucosuria and HbA1c levels already after 4 months of treatment in the silymarin group. In addition, there was a significant decrease (p<0.01) in fasting insulin levels and mean exogenous insulin requirements in the treated group, while the untreated group showed a significant increase (p<0.05) in fasting insulin levels and a stabilized insulin need. These findings are consistent with the significant decrease (p<0.01) in basal and glucagon-stimulated C-peptide levels in the treated group and the significant increase in both parameters in the control group. Another interesting finding was the significant decrease (p<0.01) in malondialdehyde/levels observed in the treated group.. These results show that treatment with silymarin may reduce the lipoperoxidation of cell membranes and insulin resistance, significantly decreasing endogenous insulin overproduction and the need for exogenous insulin administration.

Topics: Aged; Antioxidants; Blood Glucose; C-Peptide; Diabetes Mellitus, Type 2; Female; Glycosuria; Humans; Hyperinsulinism; Insulin; Liver Cirrhosis, Alcoholic; Male; Malondialdehyde; Middle Aged; Silymarin; Time Factors

Cirrhosis is characterized by paradoxical growth hormone secretion in response to glucose and insulin infusion. To ascertain whether this abnormality contributes to insulin resistance, euglycemic hyperinsulinemic glucose clamps were performed on six patients with cirrhosis and six normal control subjects. Each patient with cirrhosis underwent two clamps in random order, a clamp with somatostatin (250 micrograms/hr) together with insulin and glucagon replacement, and a control clamp without somatostatin. The normal subjects underwent the control clamp only. During the control clamp, growth hormone levels were considerably higher in the patients with cirrhosis (6.1 +/- 0.4 vs. 0.5 +/- 0.4 mU/L, p < 0.02), and glucose uptake was considerably lower (3.29 +/- 0.56 vs. 9.52 +/- 1.14 mg/kg/min, p < 0.001). Indirect calorimetry indicated that the defect was accounted for by lower nonoxidative glucose disposal (1.23 +/- 0.45 vs. 6.00 +/- 0.73, p < 0.001). Peripheral glucose uptake, exemplified by forearm glucose uptake (0.27 +/- 0.04 vs. 1.22 +/- 0.42 mg/100 ml/min, p < 0.02), and calculated insulin sensitivity (24 +/- 8 vs. 114 +/- 20 microliters/kg/min per mU/L) were particularly diminished. In the patients with cirrhosis somatostatin suppressed growth hormone levels (6.1 +/- 1.2 to 1.2 +/- 0.4 mU/L, p < 0.05). However, no significant changes occurred in whole-body glucose uptake (3.29 +/- 0.56 vs 3.01 +/- 0.54 mg/kg/min), forearm glucose uptake (0.27 +/- 0.04 vs 0.30 +/- 0.01 mg/100 ml/min) or insulin sensitivity (24 +/- 8 vs, 35 +/- 10 microliters/kg/min/mU/L, p = 0.42).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; C-Peptide; Calorimetry, Indirect; Fatty Acids, Nonesterified; Glucose; Glucose Clamp Technique; Growth Hormone; Humans; Insulin Resistance; Insulin-Like Growth Factor I; Liver; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Somatostatin

The effects of glucose and insulin administration on splanchnic and leg exchange of glucose were investigated in seven patients with cirrhosis and six sex- and age-matched healthy controls using the catheter technique. After a basal period, glucose infusion (1 mg.kg-1.min-1) was given for 45 min, followed by a 2-h euglycemic insulin clamp (1 mU.kg-1.min-1). In the basal state insulin levels were significantly higher in patients than in controls (25 +/- 4 vs. 7 +/- 2 microU/ml). Net splanchnic glucose output tended to be lower in patients than in controls (0.50 +/- 0.16 vs 0.73 +/- 0.11 mmol/min nonsignificant), as did leg glucose uptake (0.06 +/- 0.01 vs 0.08 +/- 0.02 mmol/min, non-significant). Glucose infusion resulted in a significant rise in leg glucose uptake, while net splanchnic glucose output decreased in both groups. During the euglycemic insulin clamp, insulin concentrations rose to 110 +/- 10 and 80 +/- 8 microU/ml in patients and controls, respectively. C-peptide concentrations decreased in the healthy controls but were unchanged from the basal level in patients with cirrhosis. Glucose disposal during the last half hour of the clamp was 1.12 +/- 0.08 and 3.19 +/- 0.04 mmol/min in patients and controls, respectively (p < 0.001). Glucose was taken up by the splanchnic region in both groups but this uptake was significantly greater in patients than in controls (0.42 +/- 0.05 vs. 0.25 +/- 0.06 mmol/min, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Basal Metabolism; Blood Glucose; C-Peptide; Female; Glucose; Humans; Infusions, Intravenous; Insulin; Leg; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Muscle, Skeletal; Reference Values; Splanchnic Circulation

Insulin secretion is increased in cirrhotic patients without diabetes but decreased in cirrhotic patients with diabetes. Increased glucagon secretion is found in both groups. Our aim was to determine: 1) whether alterations in insulin secretion are due to changes in maximal secretory capacity or altered islet B-cell sensitivity to glucose, and 2) whether regulation of glucagon secretion by glucose is disturbed.. Insulin, C-peptide and glucagon levels were measured basally and during 12, 19 and 28 mmol/l glucose clamps, and in response to 5 g intravenous arginine basally and after 35 min at a glucose of 12, 19 and 28 mmol/l in 6 non-diabetic alcoholic cirrhotic patients, six diabetic alcoholic cirrhotic patients and six normal controls.. Fasting insulin, and C-peptide levels were higher in cirrhotic patients than controls but not different between diabetic and non-diabetic patients. C-peptide levels at t=35 min of the clamp increased more with glucose concentration in non-diabetic cirrhotic patients than controls; there was little increase in diabetic cirrhotic patients. At a blood glucose of approximately 5 mmol/l the 2-5 min C-peptide response to arginine (CP[ARG]) was similar in all groups, but enhancement of this response by glucose was greater in non-diabetic cirrhotic patients and impaired in diabetic cirrhotic patients. Maximal insulin secretion (CP(ARG) at 28 mmol/l glucose) was 49% higher in the non-diabetic cirrhotic patients than controls (p<0.05); in diabetic cirrhotic patients it was 47% lower (p<0.05). The glucose level required for half-maximal potentiation of (CPARG) was not different in the three groups. Cirrhotic patients had higher fasting glucagon levels, and a greater 2-5-min glucagon response to arginine, which was enhanced by concomitant diabetes (p<0.001 vs controls). Suppression of plasma glucagon by hyperglycaemia was markedly impaired in diabetic cirrhotic patients (glucagon levels at 35 min of 28 mmol/l glucose clamp: diabetics, 139 x/divided by 1.25 ng/l, non-diabetic cirrhotic patients, 24 x/divided by 1.20, controls, 21 x/divided by 1.15, p<0.001). Suppression of arginine-stimulated glucagon secretion by glucose was also impaired in diabetic cirrhotic patients, and to a lesser extent in non-diabetic cirrhotic patients.. Insulin secretory abnormalities in diabetic and non-diabetic cirrhotic patients are due to changes in maximal secretory capacity rather than altered B-cell sensitivity to glucose. The exaggerated glucagon response to arginine in alcoholic cirrhotic patients is not abolished by hyperglycaemia/hyperinsulinaemia. In diabetic alcoholic cirrhotic patients, the inhibitory effect of glucose on basal glucagon secretion is also markedly impaired.

Topics: Adult; Aged; Arginine; Basal Metabolism; Blood Glucose; C-Peptide; Case-Control Studies; Diabetes Complications; Diabetes Mellitus; Dose-Response Relationship, Drug; Glucagon; Glucose; Humans; Hyperglycemia; Insulin; Insulin Secretion; Islets of Langerhans; Liver Cirrhosis, Alcoholic; Middle Aged; Secretory Rate

To characterize the pulsatile liberation of pancreatic hormones, blood was taken from the portal vein of four patients (three men, one woman; aged 65-71 years) with alcoholic (n = 3) or posthepatitic (n = 1) liver cirrhosis. The concentrations of glucose, insulin, C-peptide and glucagon were measured within one minute. The concentrations of insulin, C-peptide and glucagon varied considerably in intervals of 4.1-6.5 min. The swings in insulin concentration ranged between 17 and 163.5 microU/ml. Oral glucose loading with 100 g increased the insulin and C-peptide swings, but not their periodicity. This indicates that pulsatile insulin secretion is amplitude not rate driven.

Topics: Aged; Blood Glucose; C-Peptide; Catheterization, Peripheral; Female; Glucagon; Glucose; Hepatitis; Humans; Insulin; Insulin Secretion; Liver Cirrhosis; Liver Cirrhosis, Alcoholic; Male; Portal Vein; Pulsatile Flow; Radiography, Interventional; Time Factors

1. To examine the contributions of hypersecretion and decreased insulin clearance to the hyperinsulinaemia of cirrhosis, insulin secretion was calculated over the day from serum C-peptide concentrations and C-peptide metabolic clearance rate. The latter was measured during infusions of recombinant human C-peptide. In cirrhotic patients (n = 9) insulin secretion rate was twice that of normal control subjects (n = 10), both in the basal state [02.00-07.00 hours, 15.7 +/- 2.1 (mean +/- SEM) nmol/h (2.6 +/- 0.4 units/h) versus 7.0 +/- 0.9 nmol/h (1.2 +/- 0.2 units/h), P < 0.002] and over 24 h [787 +/- 93 nmol (132 +/- 16 units) versus 346 +/- 34 nmol (58 +/- 6 units), P < 0.001]. However, the area under the serum insulin concentration curve was approximately six times greater in the cirrhotic patients (24 h basal, 6.3 +/- 1.0 versus 1.1 +/- 0.3 nmol l-1 h, P < 0.001; 24 h total, 21.7 +/- 3.2 versus 3.7 +/- 0.7 nmol l-1 h, P < 0.001). Thus, despite impairment of insulin clearance there is continuing hypersecretion of insulin in cirrhosis. 2. The relationship of carbohydrate and lipid metabolism with insulin secretion was assessed. In cirrhotic patients, 24 h blood glucose profiles showed a worsening of glucose tolerance over breakfast, despite greater insulin secretion compared with other meals, suggesting that the insulin insensitivity of cirrhosis is worse at this time. 3. Cirrhotic patients showed impaired suppression of blood glycerol levels after meals but normal suppression of serum non-esterified fatty acid concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: 3-Hydroxybutyric Acid; Adult; Aged; Blood Glucose; C-Peptide; Circadian Rhythm; Female; Glycerol; Humans; Hydroxybutyrates; Insulin; Insulin Secretion; Lactates; Lactic Acid; Lipid Metabolism; Liver; Liver Cirrhosis, Alcoholic; Male; Middle Aged

To assess if spontaneous portosystemic shunting from collaterals contributes to the hyperinsulinemia of cirrhosis, 12 patients with alcoholic cirrhosis underwent a 5-hour oral glucose tolerance test 1 day before and 10 days after an elective side-to-side portacaval shunt. The glucose, insulin, and C peptide responses to oral glucose post-shunt were exaggerated but comparable to preoperative values. Compared with preoperative values, the fasting molar ratio of C peptide to insulin postoperatively had increased 40% (6.0 +/- 1.2 versus 8.4 +/- 0.7), indicating improved hepatic function. These results suggest that extrahepatic portosystemic shunting secondary to spontaneous splanchnic collaterals plays little or no role in the hyperinsulinemia of cirrhosis. It appears that decreased hepatic degradation of insulin in these patients is secondary to hepatocellular dysfunction rather than a result of shunting of portal blood around the liver.

Topics: Adult; C-Peptide; Female; Glucose; Glucose Tolerance Test; Humans; Hypertension, Portal; Insulin; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Portacaval Shunt, Surgical; Portal System; Venous Pressure

Energy expenditure and substrate metabolism were investigated in 10 patients with alcoholic liver cirrhosis (EtOH-Ci) and 10 healthy controls (C). Resting metabolic rate (RMR) varied from 1,269 to 2,467 kcal/day in C and from 1,228 to 2,098 kcal/day in EtOH-Ci. RMR was significantly related to fat-free mass (FFM) in both groups, but EtOH-Ci decreased FFM and increased RMR when expressed per kilogram FFM (+33%). Glucose intolerance, hyperinsulinemia, and a decreased C-peptide-to-insulin ratio were observed in EtOH-Ci after a test meal. Concomitantly, nonoxidative glucose metabolism was reduced in association with normal increases in glucose oxidation. EtOH-Ci reduced insulin sensitivity (-59%) and maximal insulin-dependent glucose disposal (-40%) during a sequential two-step glucose clamp protocol (phase 1: 1 mU.kg body wt-1.min-1 insulin infusion rate + euglycemia; phase 2: 4 mU.kg body wt-1.min-1 insulin infusion rate + 165 mg/dl plasma glucose concentration). This was explained by reduced glucose storage (-99%, -51%) in association with normal responses in glucose oxidation rate, plasma lactate concentration, lipid oxidation rate, and rate of lipogenesis. Defective glucose storage was independent of reduced FFM. EtOH-Ci increased glucose-induced thermogenesis by 57%. We conclude that increased resting metabolic rate, enhanced thermogenesis, defective glucose storage, and normal glucose oxidation together result in increased energy needs and favor negative energy balance in patients with alcoholic cirrhosis.

Topics: Adult; Basal Metabolism; Blood Glucose; Blood Proteins; C-Peptide; Calorimetry; Energy Metabolism; Female; Humans; Insulin; Lactates; Liver Cirrhosis, Alcoholic; Male; Reference Values

Insulin action on carbohydrate metabolism is known to be reduced in liver cirrhosis. However, little is known about the effect of insulin on free fatty acid (FFA) metabolism in these patients. To investigate this aspect we performed a two-step insulin euglycemic clamp in 11 cirrhotic patients and 6 controls. Insulin was infused at 0.25 mU/Kg min from 0 to 100 min and at 1 mU/Kg from 100 to 200 min. The FFA lowering capacity of insulin was studied during the first step; the glucose metabolizing capacity (M) was evaluated during the second step. In the cirrhotic patients, the M value was lower than in controls (3.91 +/- 0.48 vs 7.75 +/- 1.09 mg/kg/min, respectively). During the low insulin infusion, FFA and glycerol plasma levels were decreased in both groups. However, the ability of insulin to suppress plasma FFA and glycerol was lower in cirrhotics than in controls. In fact, at 100 min, FFA were 50% of basal values in cirrhotics and 20% in controls (p less than 0.01), while glycerol plasma levels decreased to 70% of basal values in patients and to 56% in controls. The slope of the linear regression obtained between Ln-FFA concentrations vs time was significantly less in cirrhotic patients than in controls (p less than 0.001). In addition, a positive correlation was found between the M value (r = 0.70; p less than 0.01) and the slope of the Ln-FFA in each patient. These findings suggest that in cirrhotic patients the effects of insulin on both FFA and glucose metabolism are reduced.

Topics: Blood Glucose; C-Peptide; Fatty Acids, Nonesterified; Female; Glucose; Glucose Clamp Technique; Glucose Tolerance Test; Glycerol; Humans; Insulin; Insulin Resistance; Kinetics; Liver Cirrhosis; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Triglycerides

To study the consequences of hyperglycemia on glucose and nitrogen metabolism in cirrhosis, an hyperglycemic clamp was performed in 5 cirrhotic patients and 5 normal controls during two subsequent periods of 90 min, at 7.78 and then at 13.89 mmol/l. In the first period, glucose infusion and metabolic clearance rates were decreased in cirrhotics vs controls (p less than 0.05). In the second period, this difference between the two groups disappeared because of a more important enhancement in cirrhotics. Baseline plasma C peptide levels and those during hyperglycemia were the same during hyperglycemia in both groups, but plasma insulin level rose more in cirrhotics (p less than 0.05). Baseline insulin secretion following IV glucagon was reduced in cirrhotics vs controls (p less than 0.05), but became normal in the hyperglycemic state. Plasma glucagon levels were enhanced at all times in cirrhotics vs controls (p less than 0.01), but dropped more in cirrhotics vs controls (p less than 0.05). Insulin responsiveness, defined as the "glucose consumption: plasma insulin concentration" ratio was reduced in cirrhotics at 7.78 mmol/l (p less than 0.01), but was the same in both groups at 13.80 mmol/l because of a more important enhancement in cirrhotics, reflecting an improvement of insulin action probably at the post-receptor level and of non-insulin-mediated glucose transport. Hyperglycemia induced a drop in plasma concentration and muscular release of all aminoacids, excepted alanine, between the basal state and the end of the study. Aminoacid concentration rose only in cirrhotics, without any change in muscular output. In the same time, blood ammonia level rose only in cirrhotics, without reduction of muscular uptake.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; Amino Acids; Ammonia; C-Peptide; Glucagon; Glucose; Humans; Hyperglycemia; Insulin; Insulin Infusion Systems; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Nitrogen

Insulin (IRI) and C-peptide dynamics were studied after iv glucagon in 5 nondiabetic patients with ascites due to cirrhosis of the liver. Plasma and ascitic fluid samples for glucose, IRI and C-peptide determinations were obtained before and 6, 10, 15, 20 and 30 min after glucagon injection. Ascitic fluid volumes, estimated by dilution of ip injected PAH, were 6.2 to 20.5 L. The mean fasting plasma glucose [88 +/- 6.7 mg/dl (SE)] and C-peptide (1.40 +/- 0.42 ng/ml) levels were normal; mean plasma insulin was increased (17.4 +/- 3.0 microU/ml). After glucagon injection, there was a subnormal rise in plasma glucose (PG) compared to 5 mild diabetic patients without liver disease (8.4 +/- 3.5 vs 76 +/- 7.4 mg/dl). The plasma C-peptide rise was less than that of plasma IRI (54% vs 192%). The mean basal ascitic fluid concentration of glucose was 86 +/- 9.4 mg/dl, IRI 13.2 +/- 2.9 microU/ml and C-peptide 3.09 +/- 0.49 ng/ml. Total calculated basal ascitic fluid contents of glucose was 5.2-23.3 g, IRI 47, 120-290,000 microU and C-peptide 15,750-66,420 ng. These were 3-10 times the quantity of these substances circulating in the plasma volume. After glucagon injection, there was no significant increase in ascitic fluid glucose or IRI, but there was a 43% increase in C-peptide concentration at 10 min. In ascitic fluid, the molar concentration of IRI was lower and C-peptide higher than plasma, resulting in a C-peptide: IRI molar ratio of 11.31, markedly higher than the published normal plasma ratio of 4.63.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Ascitic Fluid; Blood Glucose; C-Peptide; Glucagon; Glucose; Humans; Insulin; Kinetics; Liver Cirrhosis, Alcoholic; Male; Middle Aged

Propranolol, a non-selective beta-blocker, is known to decrease glucagon release in normal subjects. The present study was aimed at investigating the effects of propranolol on the hyperglucagonism commonly observed in patients with cirrhosis. Eight cirrhotic patients and 6 matched healthy controls were studied. The plasma concentrations of glucagon, insulin, c-peptide and glucose were measured in basal conditions and after stimulating glucagon secretion by an i.v. infusion of arginine (0.4 g/kg/30 min). The study was repeated 24 h later after inducing beta-blockade by the i.v. infusion of propranolol (10 mg). In baseline conditions, patients with cirrhosis, despite normal levels of insulin and glucose, had a marked hyperglucagonism (654 +/- 303 pg/ml vs. 269 +/- 90 in controls, P less than 0.01). Prior to propranolol, arginine infusion caused greater glucagon release in cirrhotics (71 +/- 31 ng.h.ml-1) than in controls (33 +/- 17 ng.h.ml-1, P less than 0.02), but despite a similar insulin secretion (assessed from c-peptide), blood glucose did not increase. After propranolol, glucagon secretion decreased as expected in controls (29 +/- 12 ng.h.ml-1, P less than 0.05) but experienced a paradoxical increase in cirrhotics (113 +/- 64 ng.h.ml-1, P less than 0.05). Again, despite the marked increase in glucagon release, there was no increase in glucose production, providing further evidence of the glucagon resistance that accompanies hyperglucagonism in cirrhosis. Our results suggest that hyperglucagonism with glucagon resistance might be the initial disturbance in carbohydrate metabolism in patients with cirrhosis. Contrary to what could be expected, propranolol does not correct but further accentuates this disturbance.

Topics: Adult; Arginine; Blood Glucose; C-Peptide; Drug Resistance; Female; Glucagon; Humans; Liver Cirrhosis; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Propranolol

To clarify the pathogenesis of impaired glucose tolerance in patients with cirrhosis, several factors possibly affecting carbohydrate metabolism were studied in 12 cirrhotic patients with different blood glucose responses to an oral glucose tolerance test. Glucose levels, 120 min after the load, were inversely and significantly related to insulin sensitivity, measured by means of the euglycemic "glucose clamp" technique (r = -0.746). Basal and glucose-induced insulin secretion (insulin and C-peptide levels) only slightly correlated with glucose tolerance, which was not related to functional liver cell mass (galactose elimination), portal-systemic shunting (degree of varices at endoscopy), or maximal glucose-independent insulin secretion (peak C-peptide levels after a glucagon test). Multiple regression analysis identified insulin sensitivity and liver cell mass as the independent variables able to explain most of the variance of 120-min blood glucose (about 84%), and both of them contributed considerably to the regression. While reduced insulin sensitivity is probably the main cause of impaired glucose tolerance, the reduced hepatocellular mass only appears to modulate the degree, and therefore the clinical relevance, of this defect.

Topics: Adult; Aged; Blood Glucose; C-Peptide; Female; Galactose; Glucose Tolerance Test; Humans; Insulin; Insulin Resistance; Liver; Liver Cirrhosis; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Regression Analysis

In order to evaluate the relationship between nutritional status and insulin secretion in cirrhosis, the following parameters of caloric (tricipital skin fold, prealbumin) and proteic (arm muscle size, transferrin, 24 h-urinary creatinine excretion) nutritional status were compared in 20 alcoholic cirrhotics and 10 normal subjects. Insulin secretion was evaluated in both groups by insulin and C-peptide response to an intravenous glucose tolerance test and by 24 h urinary excretion of C-peptide. When compared to normals, cirrhotics have lower values for all nutritional status parameters and individually for at least three of those in 14 (70 p. 100) patients. In cirrhotics there is a significant decrease of the 4-min poststimulative response of insulin and C-peptide, contrasting with higher basal and late poststimulative values than in normals. This contrast could be explained by a reduced metabolic clearance rate of insulin (consistent with insulin resistance) and of C-peptide (the urinary clearance of which is 2.5 times lower in cirrhotics than in normals). The 24-h urinary excretion of C-peptide, probably weakly dependent of this reduced clearance, is 50 p. 100 lower in cirrhotics: 12.9 +/- 1.6 nM/24 h than in normals: 26.0 +/- 2.4 nM/24 h (p less than 0.001). In cirrhotics there is a significant linear correlation between 24 h urinary C-peptide excretion and all the nutritional status parameters but one (prealbumin). These results indicate that in cirrhosis: 1) urinary C-peptide excretion rate is a good index of insulin secretion; 2) urinary C-peptide indicates a marked deficit in insulin secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; C-Peptide; Humans; Insulin; Insulin Secretion; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Nutrition Disorders; Protein-Energy Malnutrition

The liver plays a key role in glucose homeostasis and insulin metabolism. Altered glucose and insulin levels in peripheral blood are common findings in chronic liver disease. The aim of the present study was to investigate the effect of surgical portosystemic shunt on plasma glucose and insulin responses to glucose administration in a group of cirrhotic patients. For this purpose 10 cirrhotic subjects (8 males and 2 females) aged 42 to 65 years underwent an oral glucose tolerance test (OGTT, 75 g), and an intravenous glucose tolerance test (IVGTT, 0.33 g/kg) before and after undergoing a side-to side portocaval anastomosis (PCS). 6 noncirrhotic, nondiabetic patients matched for sex, age and body weight who underwent abdominal vascular surgery served as controls. In cirrhotic subjects, the PCS resulted in: increased plasma glucose and insulin levels during OGTT; decreased C-peptide level during OGTT; unmodified plasma glucose and insulin concentrations during IVGTT. In control subjects the abdominal surgery did not affect plasma glucose and insulin responses to oral or intravenous glucose loads. These results suggest that in cirrhotic subjects surgical portocaval shunt results in: deterioration of oral but not intravenous glucose tolerance, due to an escape of ingested glucose from the liver; increased peripheral insulin response to oral glucose administration as a consequence of reduction in hepatic removal of the hormone; and decreased pancreatic response to oral glucose due possibly to a greater feed back inhibition of beta-cell. These events seem to be a consequence of the shunt per se and not of a deterioration of hepatocellular function.

Topics: Adult; Aged; Blood Glucose; C-Peptide; Female; Glucose Tolerance Test; Humans; Insulin; Liver Cirrhosis; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Portacaval Shunt, Surgical

Insulin uptake by the human cirrhotic liver was studied in six patients with Laennec's cirrhosis, and the result was compared with that found in ten control patients with varying diseases affecting the biliary system. All patients had portal catheters for diagnostic purposes. The fractional hepatic uptake of insulin was calculated from the clearance rates for insulin obtained after a constant rate infusion into a peripheral vein and the portal vein in each patient. The fractional hepatic extraction of insulin was 13% +/- 5 in cirrhotic patients and differed significantly from the fractional hepatic extraction found in controls (51% +/- 5;P less than 0.001).

Topics: Adult; Aged; Biliary Tract Diseases; Blood Glucose; C-Peptide; Female; Glucose; Humans; Infusions, Parenteral; Insulin; Liver; Liver Cirrhosis, Alcoholic; Male; Metabolic Clearance Rate; Middle Aged; Portal Vein

The purpose of our study was to evaluate the effect of somatostatin (500 microgram/h intravenously) upon insulin, c-peptide, glucagon and plasma amino acids concentrations in patients with and without cirrhosis of the liver. The typical plasma amino acid pattern in cirrhosis is characterised by increased concentrations of the aromatic amino acids and decreased concentrations of the branched chain amino acids and of alanine and glycine. After administration of somatostatin insulin, c-peptide and glucagon concentrations decreased and those of the branched chain amino acids in both groups increased; in addition in patients with cirrhosis the plasma concentrations of threonine, serine, glycine, alanine, lysine, and arginine increased also. Infusion of somatostatin plus insulin in patients with cirrhosis succeeded in preventing the increase in the branched chain amino acid concentrations, while the infusion of somatostatin plus glucagon decreased threonine, serine, glycine, alinine, phenylalanine, tyrosine, lysine and arginine concentrations. It is therefore suggested that the effect of somatostatin on the plasma amino acids may be because of the reduction of insulin and glucagon concentrations; however, other effects of somatostatin cannot be excluded at present.

Topics: Amino Acids; Amino Acids, Branched-Chain; C-Peptide; Glucagon; Humans; Insulin; Liver Cirrhosis, Alcoholic; Male; Phenylalanine; Somatostatin; Tyrosine

In order to investigate disturbances in glycoregulation and plasma amino acids and their possible relationship in alcoholic liver diseases, plasma concentrations of insulin, C-peptide, glucagon and branched-chain (valine, leucine, isoleucine) as well as aromatic (phenylalanine, tyrosine) amino acids were measured during an arginine test (i.v infusion of arginine chloride 0.5 g/kg over 30 min) in 21 alcoholic patients: 11 with cirrhosis (group C) and 10 with steatosis (group S). Insulin responses to arginine was reduced in both groups, whereas glucagon response was increased in group C and reduced in group S. Plasma concentrations of branched-chain amino acids were reduced in both groups, irrespective of the degree of hyperinsulinism. Plasma concentrations of aromatic amino acids were increased only in cirrhotic patients; the increase was independent of the degree of hyperglucagonism and of the plasma insulin/glucagon molar ratio. These results suggest that disturbances of glycoregulation in plasma amino acids imbalance do not play a major role in alcoholic cirrhosis and steatosis.

Topics: Adult; Amino Acids; Arginine; Blood Glucose; C-Peptide; Fatty Liver, Alcoholic; Female; Glucagon; Humans; Insulin; Liver Cirrhosis, Alcoholic; Liver Diseases, Alcoholic; Male; Middle Aged

The possible contribution of hepatocellular damage and portal-systemic shunting to hyperinsulinism in cirrhosis was studied in 23 cirrhotics, 8 of whom had a surgical portacaval shunt, and 16 controls by measuring insulin and the connecting peptide (C-peptide) concentrations in simultaneous samples of peripheral arterial and hepatic venous blood. The fractional hepatic insulin extraction (0.48 +/- 0.06, mean +/- SE) was normal in cirrhosis. The hepatic insulin elimination rate was directly related to arterial insulin levels (r = 0.91, P less than 0.001) even at very high circulating levels. Extrahepatic insulin metabolism was measured across the kidney and lower limb. There were no significant differences between cirrhotics and control subjects in relation to renal (0.25 +/- 0.05 vs. 0.23 +/- 0.04) and lower limb insulin extraction (0.14 +/- 0.07 vs. 0.19 +/- 0.04). While in the control group hepatic venous insulin (0.143 +/- 0.018 pmol/ml) markedly exceeded the peripheral insulin concentration (0.083 +/- 0.009 pmol/ml, P less than 0.01), the contrary was found in cirrhotics with end-to-side portacaval shunt in whom all the pancreatic venous effluent is shunted to the systemic circulation (hepatic venous insulin, 0.130 +/- 0.028 pmol/ml; peripheral, 0.234 +/- 0.037 pmol/ml; P less than 0.01). Portal-hypertensive cirrhotics without a surgical portacaval shunt also had hepatic venous insulin levels (0.132 +/- 0.029 pmol/ml) below peripheral arterial insulin concentrations (0.205 +/- 0.041 pmol/ml, P less than 0.01). The study suggests that hyperinsulinism in cirrhosis is not the result of an intrinsic defect of hepatic insulin metabolism but of the spontaneous shunting of portal blood to the systemic circulation.

Topics: C-Peptide; Humans; Hyperinsulinism; Hypertension, Portal; Insulin; Kidney; Liver; Liver Cirrhosis; Liver Cirrhosis, Alcoholic; Portal System; Portasystemic Shunt, Surgical

Changes in blood glucose and insulin metabolism, both under basal conditions and after glucose and glucagon stimulus, were studied in 95 patients with chronic alcoholic hepatopathy. Peptide C was also determined in 19 patients. A high incidence of islet-cell insufficiency was noted. Stress is laid on the multiplicity of the pathogenetic mechanisms responsible for blood glucose and insulin changes during chronic alcoholic hepatopathy, particularly liver cell damage, hyperglucagonaemia, organic and/or functional islet-cell insufficiency, and peripheral insulin resistance. It is felt that the last two of these are of major importance, whereas liver cell damage is of secondary significance, at any rate as far as glucose and insulin turnover is concerned.

Topics: C-Peptide; Fatty Liver, Alcoholic; Female; Glucose Tolerance Test; Humans; Insulin; Insulin Secretion; Liver Cirrhosis, Alcoholic; Liver Diseases, Alcoholic; Male; Middle Aged

Patients with hepatic cirrhosis often have demonstrable glucose intolerance. We studied 21 patients with cirrhosis of the liver. Oral glucose tolerance tests (OGTT), intravenous arginine stimulation tests (IVAST), and intravenous insulin tolerance tests (IVITT) were performed, and timed blood samples were obtained for the assay of glucose immunoreactive insulin (IRI), C-peptide (C-P), and immunoreactive glucagon (IRG). The 125I-insulin binding to circulating monocytes was studied in some of the patients. All results were compared to those of similar studies performed on healthy controls. During OGTT significant glucose intolerance was demonstrable in the patients with cirrhosis (2 hr plasma glucose 198.8 +/- 14.3 mg/dl in cirrhosis and 116.4 +/- 4.2 in controls; p less than 0.001). Two-hour plasma IRI, C-P, and IRG were significantly higher in the cirrhotic patients than in controls (p less than 0.001; less than 0.001; less than 0.025). In response to IVAST, the patients with cirrhosis showed a greater first-phase insulin secretion and controls had a slightly better second-phase insulin release. Plasma IRG rose from a basal value of 446 pg/ml to 1100 in the patients with cirrhosis and from 171 pg/ml to 494 in controls. After intravenous insulin administration, there was only a 40% decline in plasma glucose concentration from basal values in the patients with cirrhosis whereas the controls showed a 60% decline, demonstrating that the patients with cirrhosis had significant insulin resistance. Moreover, the half-life of insulin was prolonged in the patients with cirrhosis (t 1/2 = 15.5 min in cirrhosis and 10.3 in controls; p less than 0.001); and the ratio of C-P to insulin during OGTT was also reduced, indicating that the patients with cirrhosis have reduced hepatic clearance of insulin. The specific binding of 125I-insulin to circulating monocytes was 2.7% in cirrhosis, 2% in obese controls, and 4% in lean controls. There was a significant negative correlation between the fasting plasma insulin values and the specific binding of insulin. In conclusion, patients with hepatic cirrhosis have significant glucose intolerance characterized by hyperinsulinemia, hyperglucagonemia, insulin resistance, and down-regulation of insulin receptors. Although hyperinsulinemia is probably caused by reduced hepatic clearance of insulin, hyperglucagonemia is primarily due to increased pancreatic secretion.

Topics: Adult; Arginine; Blood Glucose; C-Peptide; Glucagon; Glucose Tolerance Test; Humans; Hyperinsulinism; Insulin; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Monocytes

Glucose tolerance and B cell function were assessed in 30 consecutive chronic alcoholic patients without overt diabetes mellitus. Plasma glucose, insulin, and C peptide concentrations were measured during an oral glucose tolerance test. All patients underwent a liver biopsy and an exocrine pancreatic function test (Lundh test). Compared with the controls, the three groups of alcoholic patients (those with histologically normal livers, n = 12; those with steatosis, n = 10; and those with cirrhosis, n = 8) all had a two-fold increase in plasma concentrations of insulin as well as C peptide in the fasting state, despite normal fasting levels of glucose. After oral glucose all groups of patients had elevated plasma levels of glucose, insulin, and C peptide compared with the controls. The C peptide/insulin ratio was similar to that in the controls in all groups of alcoholics. Patients with decreased exocrine pancreatic function (n = 7) had a significantly lower insulin and C peptide response to glucose than the patients with normal exocrine pancreatic function. It is concluded that (1) chronic alcoholics even with histologically normal livers have endogenous insulin resistance, and (2) associated damage to the exocrine pancreas is more common than previously recognized and decompensation of B cell function could be demonstrated in patients with decreased exocrine pancreatic secretion.

Topics: Adolescent; Adult; Alcoholism; Blood Glucose; C-Peptide; Glucose Tolerance Test; Humans; Insulin; Islets of Langerhans; Liver; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Pancreas

Topics: Adult; Blood Glucose; C-Peptide; Fasting; Galactose; Glucose Tolerance Test; Humans; Insulin; Liver Cirrhosis, Alcoholic; Male; Middle Aged

The responses of portal, hepatic and peripheral venous blood glucose (BG), plasma insulin (IRI) and C-peptide (IRC) levels to iv tolbutamide (200 mg) have been determined in 9 non-diabetic patients with liver cirrhosis and in 6 control subjects. The basal levels of plasma IRI and IRC were similar in patients and controls as were the portal and peripheral BG levels. In the hepatic vein, however, the BG-levels were higher in cirrhotic patients than in controls. After tolbutamide administration the BG-levels were unchanged in the cirrhotic patients but a significant fall in hepatic vein BG was observed in controls. In both groups of subjects the highest post-tolbutamide IRI-levels were found in the portal vein whereas the corresponding IRC-levels were as high in the hepatic as in the portal vein. The increments of portal venous IRI and IRC were significantly higher in controls as compared to the cirrhotic patients. Nevertheless, in the peripheral veins the increments of IRI and IRC were very similar in both groups of subjects or even less in the control subjects. The results suggest that in patient with liver cirrhosis the secretion of insulin is not increased but slightly decreased. The production of glucose by the liver also seems to be increased either due to insulin resistance or portal venous shunting of insulin.

Topics: Adult; Blood; Blood Glucose; C-Peptide; Female; Hepatic Veins; Humans; Insulin; Liver Cirrhosis; Liver Cirrhosis, Alcoholic; Liver Cirrhosis, Biliary; Male; Middle Aged; Peptides; Portal Vein; Tolbutamide; Veins

Topics: Adolescent; Adult; Blood Glucose; C-Peptide; Female; Growth Hormone; Hepatitis, Viral, Human; Humans; Hydrocortisone; Insulin; Liver Cirrhosis, Alcoholic; Male; Middle Aged

Topics: Adult; Aged; C-Peptide; Endoscopy; Female; Glucose Tolerance Test; Humans; Insulin; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Pancreatic Ducts; Radiography

Basal and reactive peripheral hyperinsulinism recorded in alcoholic hepatic disease may result from decreased hepatic breakdown or pancreatic hypersecretion. C-peptide (CPR) and insulin (IRI) concentrations were measured in 3 groups of 8 alcoholic patients--steatosis, compensated and decompensated cirrhosis--and compared with 8 normal subjects in order to determine the importance of these two possibilities. At basal state, the molar ratio CPR/IRI was near the normal (8.7 +/- 0.9) but is diminished in the 8 hyperinsulinaemic patients (5.9 +/- 0.6). After i.v. glucose tolerance test and tolbutamide stimulations, an hyperreactivity of IRI and CPR may be noted in cirrhotics. A relative insensitivity of the B-cell to glucose appeared after comparison with the effect of tolbutamide. Thus basal hyperinsulinism resulted of decreased hepatic breakdown and stimulated hyperinsulinism resulted of hypersecretion. Glucose intolerance and anomalies of the insulin secretion were more apparent with severe hepatic disease.

Topics: Adolescent; Adult; C-Peptide; Fatty Liver, Alcoholic; Female; Glucose Tolerance Test; Humans; Hyperinsulinism; Insulin; Insulin Secretion; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Peptides; Tolbutamide