Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015695 (fatty liver)
 13,941 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The hepatic toxicity of TPN that is seen clinically appears to be multifactorial in origin. Most patients develop a combination of hepatic steatosis with evidence of cholestasis and abnormalities in liver function. The model that we have studied is one of pure hepatic steatosis since, on repeated study, these rats do not develop any liver function abnormalities. It is unclear whether this is related to the fact that these are short-term experiments, that rat livers respond differently from humans, or that rats do not have gallbladders. It has not been possible to carry these experiments out beyond 3 weeks since the rats develop bacterial colonization of the central lines as well as evidence of line sepsis. thus confounding the issue of hepatic toxicity being due to the TPN or to sepsis. One hypothesis is that hepatic steatosis is an early marker of liver toxicity and that prevention or reversal of hepatic steatosis may protect the liver from further abnormality. Insulin and glucagon seem to play a critical role in the development of TPN-associated hepatic steatosis. Specifically, an elevated portal venous insulin-glucagon molar ratio appears to be the primary stimulus and any treatment that lowers this ratio should diminish hepatic steatosis. The use of glucagon as a treatment modality is new. We have found no evident side effects of low dose glucagon in rats when it is added to the TPN solution. Glutamine has received much attention recently as a nutritional pharmacological agent in ameliorating some of the intestinal complications of parenteral nutrition and is well tolerated when administered appropriately. Intravenous lipid administration is an important nonprotein calorie source, especially when a high dextrose base cannot be used, and plays a role as well in preventing the development of hepatic steatosis. Thus, it is suggested that the clinical treatment of hepatic steatosis during TPN can be safely performed using any one, or a combination, of these modalities and without having to discontinue the TPN infusions. Since we observed no deterioration of liver function in rats receiving TPN for up to 2 weeks, we cannot completely relate these findings and recommendations to the hepatic dysfunction seen clinically with the use of TPN. Additional study will be required before this can be conclusively determined.
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PMID:Pathogenesis of hepatic steatosis during total parenteral nutrition. 190 28

Most rodents that spontaneously develop non-insulin-dependent diabetes mellitus are obese. The exception is the BHE rat. This rat develops abnormal glucose tolerance by 300 days of age, is lipemic, has a fatty liver, and yet is not obese. The strain has existed for at least 40 years and almost 100 research papers have been published describing its metabolic characteristics and responses to diet manipulation. A subline that has a higher percentage of diabetic animals has been produced. These animals may be useful in the study of mild diabetes that exists in the absence of obesity. Berdanier, C.D. The BHE rat: an animal model for the study of non-insulin-dependent diabetes mellitus.
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PMID:The BHE rat: an animal model for the study of non-insulin-dependent diabetes mellitus. 202 12

The article reviews the effect of diabetes on the pharmacokinetics and pharmacodynamics of drugs in humans. For most drugs which cross the gastrointestinal wall by passive diffusion, oral absorption is unlikely to be affected by diabetes, although a delay in the absorption of tolazamide and a decrease in the extent of absorption of ampicillin have been reported. Subcutaneous absorption of insulin is more rapid in diabetic patients, whereas the intramuscular absorption of several drugs is slower. The binding of a number of drugs in the blood is reduced in diabetes, which may be due to glycosylation of plasma proteins or displacement by plasma free fatty acids, the level of which is increased in diabetic patients. Plasma concentrations of albumin and alpha 1-acid glycoprotein do not appear to be changed by the disease. The distribution of drugs with little or no binding in the blood is generally not altered, although the volume of distribution of phenazone (antipyrine) is reduced by 20% in insulin-dependent diabetes mellitus (IDDM). In contrast to animal studies, the metabolic clearance of most drugs in humans appears to be unaffected or slightly reduced by the disease. The presence of fatty liver in non-insulin-dependent diabetes mellitus (NIDDM) may contribute to a reduced hepatic clearance, whereas decreased binding in the blood may cause an increase in clearance. The effect of diabetes on hepatic blood flow in humans appears to be unknown. Diabetes affects kidney function in a significant number of diabetic patients. During the first 10 years after the onset of the disease, glomerular filtration is elevated in these patients. Thus, the renal clearance of a number of antibiotics has been shown to be increased in diabetic children. As the disease progresses, renal function is impaired and glomerular function declines from the initial elevated state. In diabetic adults the renal clearance of drugs either is comparable with that found in nondiabetic individuals or is reduced. A limited number of studies have been conducted comparing the dose-response of cardiovascular drugs in diabetic patients with that in nondiabetic controls. Decreased, increased and unchanged responses have been reported. It is apparent that in some cases an altered response may be observed for a drug when administered to a diabetic patient compared with a similar nondiabetic individual. At the present time, it is not possible to ascertain whether these studies reflect true pharmacodynamic changes or merely alterations in pharmacokinetics.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The effects of diabetes mellitus on pharmacokinetics and pharmacodynamics in humans. 204 31

Infusion of total parenteral nutrition (TPN) with excess carbohydrate calories leads to hepatic steatosis in rats and is associated with an elevated portal insulin/glucagon molar ratio. Previously we have shown that adding glucagon to TPN prevents and reverses hepatic steatosis in rats, possibly by increasing hepatic lipid export. It has been reported that steatosis is eliminated in rats by the addition of L-glutamine to TPN. In this study, we examined the effect of glutamine on portal insulin and glucagon levels and the development of hepatic steatosis. Adult rats (n = 19) received internal jugular catheters: Group 1 (n = 6), saline (3 cc/hr) and chow ad libitum; Group 2 (n = 7), 25% dextrose base TPN; Group 3 (n = 6), 25% dextrose base TPN with 2% glutamine. The infusion rate of TPN was 1.2 cc/100 g body wt/hr. Daily nitrogen balance was determined and at 7 days, portal venous blood was drawn for insulin and glucagon radioimmunoassay, livers were removed for histology and lipid content determination, and the small intestines were removed for mucosal protein and DNA content determination. Panlobular vacuolization of the hepatocytes was noted on histology in Group 2 (TPN) while Group 1 (chow) and Group 3 (TPN + glutamine) showed normal liver morphology. Hepatic lipid content was significantly elevated in Group 2 (P less than 0.05). The portal insulin/glucagon molar ratio was increased because of excessive portal venous insulin in Group 2 (TPN). In contrast, portal glucagon was significantly elevated while the insulin/glucagon ratio and hepatic lipid content did not increase above control levels in the glutamine-supplemented Group 3 rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Addition of L-glutamine to total parenteral nutrition and its effects on portal insulin and glucagon and the development of hepatic steatosis in rats. 211 67

Total Pancreatectomy was performed under nembutal anesthesia in 16 adult mongrel dogs after a 24-hour fast, and the depancreatized dogs were given parenteral nutrition containing fat emulsion. Serum lipids, intravenous fat tolerance and post-heparin lipolytic activity were determined and liver biopsy was done to demonstrate the presence or absence of fatty liver. The animals were divided into three groups: group A (n = 6) received fat emulsion 1 g/kg/day; group B (n = 5), fat emulsion 2 g/kg/day; and group C (n = 5), no fat emulsion. Blood levels of cholesterol and phospholipid were increased in group B, while only a mild elevation of the blood triglyceride (TG) level was noted in group A. In group C, cholesterol and phospholipid levels were decreased, and hypoglycemia was liable to occur. The rate of disappearance of blood fat (K2) was decreased two weeks after surgery in group B, but there were no significant change in the other two groups. These findings suggest that if insulin is present, the administration of fat emulsion will not cause fatty liver.
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PMID:Effect of intravenously administered fat emulsion on liver function in totally depancreatized dogs. 213 Jul 72

The possibility that postprandial hyperinsulinemia could play a role in the development of hepatic lipid disturbances during convalescence from influenza B infection was explored in the ferret as a possible model of the steatosis of Reye's syndrome. Postprandial hyperinsulinemia was produced by feeding young ferrets glucose/water and a regular diet (glucose-treated group), as reflected by the mean serum insulin levels attained, which were 57 and 135 microU/ml during control and postinfluenza periods, respectively. By comparison, ferrets fed water and a regular diet (untreated group) had mean insulin levels of 19 and 22 microU/ml, while postprandial glucose levels were comparable in the two groups of animals for each period. In contrast to untreated animals, grossly visible fatty livers were found in glucose-treated ferrets during convalescence. The total lipid content of these livers had doubled compared with preinfection samples and compared with livers of untreated ferrets. By electron microscopy hepatic mitochondria showed striking changes with diminution of matrix density and reduction in cristae surface area only in convalescent samples from glucose-treated animals. Serum free fatty acid (FFA) levels were considerably higher in the glucose-treated animals during fasting before influenza and also after feeding during convalescence. Serum triglyceride (TG) levels were also high during convalescence in the glucose-treated group. Adipose tissue lipoprotein lipase activities were similar between groups, but hormone-sensitive lipase activity was twelvefold higher in glucose-treated ferrets before and after influenza B. These findings indicate that for a given stimulus, glucose-treated ferrets would mobilize more FFA than untreated ferrets. The total capacity for beta-oxidation of FA by the mitochondrial pathway was identical in all groups of animals. Total carnitine palmitoyl transferase (CPT) activity was the same in both control groups, but was significantly diminished in glucose-treated animals during convalescence. As CPT regulates the entry of FA into the mitochondrial matrix, its reduction in response to higher insulin concentrations would limit the oxidation of FA and stimulate TG accumulation. Therefore, the accumulation of lipid in the liver in this model is regarded to have been caused by the simultaneous occurrence of increased lipolysis and increased hepatic TG synthesis owing, in part, to diversion of activated FA by CPT, which is reduced in activity due to the regulatory action of insulin. These findings may have pathophysiologic relevance for the lipid changes that occur in Reye's syndrome and to fatty liver formation in hyperinsulinemic states.
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PMID:Hepatic steatosis during convalescence from influenza B infection in ferrets with postprandial hyperinsulinemia. 220 96

Alcoholic liver disease presents a wide spectrum of clinical manifestations ranging from mild asymptomatic fatty liver to alcoholic hepatitis and severe life-threatening liver failure with ascites, hemorrhaging esophageal varices, and encephalopathy. Although still poorly understood, the mechanism of this injury is probably the result of numerous direct toxic and metabolic effects of alcohol on the hepatocyte. Therapy consists primarily of abstinence and supportive care. However, several newer treatments are actively being studied. These include prednisolone, anabolic steroids, glucagon and insulin, propylthiouracil, and cyanidanol. Colchicine is promising as an agent to inhibit fibrosis. Complications of cirrhosis, including ascites and variceal hemorrhage, are the result of end stage disease. A return to old techniques of ascitic fluid management suggests that therapeutic large-volume paracentesis with albumin infusion is a safe and effective form of therapy. Variceal hemorrhage is best treated with sclerotherapy, vasoconstrictors, and balloon tamponade. Little has been done to alter the ultimately dismal prognosis and long-term survival of alcoholic liver disease.
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PMID:Alcoholic liver disease. 222 93

A 28-year-old man with poorly controlled juvenile-onset diabetes mellitus presented with jaundice and type 5 hyperlipoproteinemia. A liver biopsy showed fatty liver hepatitis (steatonecrosis). This case represents one end in a spectrum of lipid disorders and liver disease in diabetes mellitus. With increasing insulin deficiency, liver steatosis and the more common type 4 hyperlipoproteinemia pattern may progress to fatty liver hepatitis and type 5 hyperlipoproteinemia.
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PMID:Fatty liver hepatitis and type 5 hyperlipoproteinemia in juvenile diabetes mellitus. Case report and review of the literature. 240 34

Infusion of total parenteral nutrition (TPN) with excess carbohydrate calories leads to hepatic steatosis in rats that is associated with an elevated portal insulin/glucagon molar ratio. Previously we have shown that adding glucagon to TPN prevents hepatic steatosis in rats. In this study we attempted to reverse the steatosis by adding glucagon to TPN after 1 week of TPN alone. Adult rats (n = 28) received internal jugular catheters: Group 1 (n = 7), saline (3 cc/h) and chow ad libitum; Group 2 (n = 7), 25% dextrose base TPN solution for 1 week; Group 3 (n = 7), 25% dextrose base TPN for 2 weeks; Group 4 (n = 7), 25% dextrose base TPN for 1 week and then glucagon (15 micrograms/100 g/day) added to TPN for the second week. The infusion rate of TPN was 1.2 ml/100 g/hr (40% kcal greater than control). At 7 days (Group 2) and 14 days (Groups 1, 3, and 4) portal and peripheral venous blood levels were drawn for insulin and glucagon radioimmunoassay, blood glucose determination, and liver function tests; livers were removed for histology and lipid content determination. Blood glucose was equivalent among all groups. Liver function tests were within normal limits. Panlobular vacuolization of the hepatocytes was noted on histology in Groups 2 and 3. Hepatic lipid content was significantly elevated in Group 3. The portal insulin/glucagon molar ratio was increased because of excessive portal venous insulin in Groups 2 and 3 (P less than 0.05 by ANOVA). In contrast, portal venous insulin and the insulin/glucagon molar ratio did not increase in Group 4 and hepatic lipid infiltration was absent when glucagon was added to the TPN solution after 1 week of TPN solution alone. The results suggest that the addition of glucagon to hypertonic dextrose TPN is not only protective in preventing hepatic steatosis, but may reverse steatosis, possibly by increasing hepatic lipid export.
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PMID:Reversal of hepatic steatosis in rats by addition of glucagon to total parenteral nutrition (TPN). 249 33

We evaluated the effects of phenobarbital, an inducer, on plasma glucose and serum immunoreactive insulin levels and on hepatic glucose and drug metabolism using an animal model of non-insulin dependent diabetes mellitus. Genetically obese (ob/ob) mice, characterized by hyperglycaemia, hyperinsulinaemia, fatty liver and obesity were selected. The impairment of diabetic state with age was associated with increased activities of NADPH producing enzymes, whereas mixed function oxidase system remained unaltered. Phenobarbital reduced serum immunoreactive insulin and plasma glucose levels and decreased gluconeogenesis. Hepatic glucose phosphorylating enzyme activity increased and glucose releasing enzyme activity decreased. The demand for NADPH in drug oxidation reactions, caused by the induction phenomenon, was reflected in the elevated activities of the NADPH producing enzymes in pentose phosphate pathway and in the activities of isocitrate dehydrogenase and malic enzyme from mitochondrial oxidation reactions. Glucose metabolism of lean littermates indicated that phenobarbital induction normalizes impaired intracellular glucose handling but leaves normal glucose metabolism unaltered. Hepatic glucose production rate was related to plasma glucose, NADPH producing enzyme activities and cytochrome P450 content in the obese and lean mice.
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PMID:Effects of enzyme induction therapy on glucose and drug metabolism in obese mice model of non-insulin dependent diabetes mellitus. 250 Oct 61


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