Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of this investigation was to elucidate the factors that regulate the pattern of gene expression in purine and pyrimidine metabolism in normal liver and hepatoma. For this purpose, the action of a hormone, insulin, and the development of resistance to a chemotherapeutic agent, tiazofurin, were studied. This investigation brought detailed evidence showing that in the rat insulin exerted a profound effect on liver purine and pyrimidine metabolism by regulating the concentrations of nucleotides through controlling the activities of strategic enzymes involved in their biosynthesis. When rats were made diabetic by alloxan treatment, in the average liver cell concentrations of ATP, GTP, UTP and CTP decreased to 66, 62, 54 and 63%, respectively, of those of normal liver. Administration of insulin for 2 days returned the hepatic nucleotide concentrations to normal range; further insulin treatment for an additional 5 days raised the concentrations of ATP, GTP, UTP and CTP to 197, 352, 412 and 792% of values observed in the liver of diabetic rats. In diabetic rats the hepatic activities of OMP decarboxylase, orotate phosphoribosyltransferase, uridine phosphorylase, uridine-cytidine kinase and uracil phosphoribosyltransferase decreased to 44, 48, 70, 36 and 41% of the activities of normal liver. Insulin treatment for 2 days returned activities to normal range. Continued insulin treatment for an additional 5 days increased the enzymic activities to 3.9- to 5.3-fold of those of the liver of the diabetic rats. The regulation by insulin treatment of the activities of enzymes of de novo and salvage synthesis of UMP should explain, in part at least, the decline and increase of the uridylate pool in diabetes and after insulin treatment. In the diabetic rat hepatic CTP synthetase, the rate-limiting enzyme of CTP biosynthesis, decreased to 53% and insulin administration for 2 days restored activity to normal range. Insulin treatment for an additional 5 days increased the synthetase activity to 4-fold of the values of the diabetic liver. Thus, the behavior of liver CTP synthetase activity is tightly linked with that of the CTP pool. In the diabetic rat liver, the activity of IMP dehydrogenase, the rate-limiting enzyme of GTP biosynthesis, decreased to 24% of that of the normal liver. Insulin administration for 2 days returned the activity to normal range, yielding a 4.5-fold increase in the activity from the diabetic to the insulin-treated state.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Regulation of purine and pyrimidine metabolism by insulin and by resistance to tiazofurin. 390 7

One hundred consecutive patients with nonautoimmune chronic active hepatitis (51% HBsAg-positive), 50 patients with cirrhosis (38% HBsAg-positive), 25 patients with chronic persistent hepatitis, and 118 patients with hepatoma who were seen at this hospital were reviewed to determine the prevalence and characteristics of glucose intolerance and diabetes in these conditions. Diabetes (fasting serum glucose greater than 7.8 mmol/L, 140 mg/dl on two separate occasions) was present in 8% of patients with chronic persistent hepatitis and mild chronic active hepatitis, 44% of patients with severe chronic active hepatitis, 40% of patients with cirrhosis, and 15% of patients with hepatoma, compared with 7% of all other patients aged 35 yr or over, undergoing liver biopsy. Compared with this high prevalence of diabetes in liver disease, only 3% of diabetic patients referred to the hospital diabetic clinic had chronic hepatitis or cirrhosis. Glucose tolerance was similar in chronic active hepatitis and cirrhosis and was characterized initially by basal hyperinsulinemia, normal basal glucose levels but elevated serum glucose following glucose loading, and evidence of insulin resistance. We suggest that the high prevalence of diabetes in chronic active hepatitis and cirrhosis in Saudi Arabia is due to the insulin resistance of chronic liver disease acting over many years in a population with a high genetic predisposition to diabetes.
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PMID:Diabetes mellitus in chronic active hepatitis and cirrhosis. 608 43

Ceftizoxime (CZX), a parenteral cephalosporin derivative belonging to the so-called third generation cephalosporin is reported to have a broad antibacterial activity, particularly against Gram-negative aerobic bacilli and some anaerobes, such as Bacteroides fragilis and a good stability to beta-lactamases. Clinical study was performed on a total of 20 cases, 9 females (1 case had urinary tract infection 3 times) and 11 males, aged from 27 to 82 years. All patients had the underlying diseases. They were bronchial asthma in 3 cases, influenza in 1, chronic pulmonary emphysema in 1, pulmonary fibrosis in 1, chronic bronchitis with strongyloidiasis in 1, lung cancer in 3, esophagus cancer in 2, stomach cancer in 1, hepatoma with urolithiasis in 1, liver cirrhosis with diabetes mellitus in 1, alcoholism with strongyloidiasis in 1, cholelithiasis in 1 and congestive heart failure in 1, respectively. Clinical diagnoses for infections were 2-acute bronchitis, 2-exacerbation of chronic bronchitis, 2-broncho-pneumonia, 2-pneumonia including one suspected case, 1-obstructive pneumonia, 2-secondary pulmonary infection, 1-pulmonary infection, 3-urinary tract infection (UTI), 1-UTI with sepsis, 1-sepsis, 1-sepsis with purulent meningitis, 1-biliary tract infection and 1-infected bronchoesophageal fistula. CZX was given by intravenous drip infusion, at a dose of 1 to 2 g, twice daily for 3 to 15 days. Because of severity in infections and underlying diseases, some cases were treated either steroid, gamma-globulin preparations or other antibiotics in combination with CZX. Twelve out of 15 cases assessed clinically responded satisfactorily to the treatment and efficacy rate was 80.0%.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Effectiveness of ceftizoxime on various infections in patients with underlying diseases]. 609 Jul 23

We have studied the effects of chronic exposure to insulin on the binding and the biologic activity of the hormone using a well-differentiated cell line (Fao) derived from the Reuber H35 rat hepatoma. Prolonged incubation (24 h) with 10(-6) M insulin produced a 20-25% decrease in binding of tracer concentrations (2 X 10(-11) M) of 125I-insulin, and a leftward shift of the curve for inhibition by unlabeled insulin. Scatchard analysis of the binding data revealed that a 75-80% decrease in the number of binding sites had occurred in the insulin-treated cells, but was accompanied by an increase in apparent receptor affinity. Kinetic studies suggested negative cooperativity in insulin binding and indicated that the change in affinity was accounted for by a decrease in the rate of dissociation. Both the decrease in receptor number and the increase in affinity were dependent on time, temperature, and the insulin concentration during the treatment period. Both effects were also blocked by cycloheximide, suggesting that they required new protein synthesis. Plasma membranes isolated from downregulated cells retained both the change in receptor number and affinity. Anti-receptor antibodies present in two human sera (B-2 and B-9) inhibited 125I-insulin binding in downregulated cells with equal or slightly greater sensitivity than in control cells. The changes in insulin binding were accompanied by changes in insulin's biologic effects in these cells.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1984 May
PMID:Insulin receptor regulation and desensitization in rat hepatoma cells. Concomitant changes in receptor number and in binding affinity. 614 7

A rapid method for determining urinary indole-3-acetic acid (IAA) is introduced as the tumor-marker for the screening and diagnostic purpose of cancer patients by means of high performance liquid chromatography (HPLC). Its clinical significance is discussed along with a review of literatures. The IAA concentration and creatinine level of optionally collected urine samples were measured and used for the calculation of IAA amount per unit creatinine (microgram IAA/mg creatinine) in urine. Thus, an amount of 24-hours urinary IAA could be calculated without collecting a whole day's urine supply. Analysis of urinary IAA was performed within 10 minutes by HPLC. Urinary IAA level is usually high in the patients with the upper G-I tract cancers such as gastric cancer, esophageal cancer and hepato-biliary tract cancer, and also malignant hematopoietic disorders. But it is also high in non-cancer patients such as liver cirrhosis, diabetes mellitus and cholelithiasis occasionally. The patients with high urinary IAA level also showed high urinary levels of 5-hydroxy indoleacetic acid (5-HIAA) and monoamine oxidase activity (MAO). It was characteristic that hepatocellular carcinoma showed slight elevation of urinary IAA with normal levels of 5-HIAA and MAO. It is conclusive that the positive rate of elevated urinary IAA level was high in the patients with gastric cancer with ulcer-forming type in its morphological classification, and its level tends to elevate as the disease progresses. Therefore, the measurement of urinary IAA level in an optionally collected urine sample, as the tumor-marker, can be useful to check the progression and regression of gastric cancer.
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PMID:[A rapid method for determining urinary indoleacetic acid concentration and its clinical significance as the tumor-marker in the diagnosis of malignant diseases]. 620 79

Insulin rapidly increases Na/K pump activity in HTC rat hepatoma cells in tissue culture, as measured by the ouabain-sensitive influx of the potassium analogue 86Rb+. Increased influx is observed within minutes and is maximal (70% above control) within 1-2 h. The effect appears to be mediated by the insulin receptors, as: the concentration dependence on insulin is identical to that for insulin induction of tyrosine aminotransferase and stimulation of 2-aminoisobutyric acid transport, proinsulin is 6% as potent as insulin, and the effect is blocked by anti-receptor antibodies. The early stimulation of potassium influx is not blocked by cycloheximide and is not associated with an increased number of pump sites as measured by 3H-ouabain binding. The insulin effect is blocked by amiloride, which blocks sodium influx, and is mimicked by the sodium ionophore monensin, which increases sodium influx and intracellular accumulation. Insulin also rapidly increases the initial rate of 22Na+ influx, suggesting that insulin may enhance Na/K pump activity, in part, by increasing intracellular sodium concentration. Incubation of HTC cells with insulin for 24 h causes complete unresponsiveness to the insulin induction of transaminase and stimulation of amino acid transport, a phenomenon mediated by postbinding mechanisms. In contrast, similar incubation with insulin does not cause unresponsiveness to the insulin stimulation of Na/K pump activity. Therefore, the site of regulation of responsiveness to insulin must be distal to, or separate from, those events causing stimulation of ion fluxes.
Diabetes 1984 May
PMID:Insulin regulation of Na/K pump activity in rat hepatoma cells. 632 35

An insulin-sensitive subcellular system was developed from rat adipocytes consisting of plasma membranes and mitochondria. Direct addition of insulin, concanavalin A or anti-insulin receptor antibody to this system resulted in the production of a mediator substance from the plasma membrane that caused dephosphorylation of the alpha subunit of pyruvate dehydrogenase in the mitochondria with concomitant activation of the enzyme. The mediator activated pyruvate dehydrogenase by activating the pyruvate dehydrogenase phosphatase and not by inhibiting the pyruvate dehydrogenase kinase. This was similar to the mechanism by which insulin causes activation of the enzyme in the intact cell. The insulin-sensitive mediator material from the adipocyte plasma membrane was acid-stable with a molecular weight of 1,000 to 1,500. Our laboratory has shown that the mediator that activates pyruvate dehydrogenase was present in intact adipocytes, hepatoma cells, and IM-9 lymphocytes. Insulin altered the amount or activity of the mediator consistent with the effect of the hormone on the cell. Other laboratories have shown similar effects on skeletal muscle and liver. We have shown the mediator to mimic insulin action on the low Km cyclic adenosine monophosphate (AMP) phosphodiesterase and the (calcium++-magnesium++)-adenosine triphosphatase (Ca++-Mg++)-ATPase of adipocyte plasma membranes in addition to pyruvate dehydrogenase. Other laboratories have shown the mediator to activate glycogen synthase. A body of direct and indirect evidence exists that demonstrates that more than one mediator exists. The chemical nature of the mediator is unknown but probably represents a new family of intracellular mediators of hormone action. These mediators may have clinical relevance in postreceptor defects of obesity and type II diabetes (noninsulin-dependent diabetes mellitus).
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PMID:The chemical mediators of insulin action: possible targets for postreceptor defects. 633 85

Patients with diffusely increased uptake in both kidneys (often referred to as "host kidneys") on Tc-99m-MDP bone imaging were evaluated. Among 2056 patients reviewed, this finding was seen in 13 patients (0.63%): four with liver cirrhosis, two with lung cancer, one each with primary hepatoma, Hodgkin's disease, malignant lymphoma, thyroid cancer, leukemia, sideroblastic anemia and diabetes mellitus. Renal vascular disease and iron overload are considered to be the major causes of this finding.
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PMID:Diffusely increased Tc-99m-MDP uptake in both kidneys. 645 33

Insulin receptors from rat hepatoma cells (Fao) and human placenta were partially purified by detergent solubilization and lectin purification. The insulin receptor preparations were subjected to sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis under reducing or nonreducing conditions. The proteins were transferred to nitrocellulose paper and the electrophoretic blots were treated with human anti-receptor autoantibodies, rabbit antibody to purified insulin receptor, or a monoclonal antibody to human insulin receptor. The nitrocellulose paper was then treated with 125I protein A or 125I second antibody followed by autoradiography. The rabbit polyclonal antiserum and one of the human autoantibodies recognized both the alpha (Mr = 135,000) and beta (Mr = 95,000) subunits after transfer from a SDS gel to nitrocellulose paper. On transfers from nonreduced gels, several high-molecular species were labeled ranging from Mr = 200,000 to Mr = 330,000. Similar high-molecular bands of the receptor were seen if highly purified human placental receptor, as well as partially purified receptor from rat or human origin, were used. As little as 0.1-0.5 microgram of pure receptor could be detected by this technique. Treatment of the receptor with neuraminidase (50 mU/ml) before gel electrophoresis resulted in a 50% increase in intensity of intact receptor and about a 70% increase in the labeling of the alpha-subunit of the receptor, but no change in labeling of the beta-subunit. The monoclonal antibody used, as well as two other human autoantibodies, did not recognize the receptor after transfer to nitrocellulose paper.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1984 Oct
PMID:Visualization of the insulin receptor by immunoblotting. 647 60

The effects of the two groups of oral agents on insulin receptors were studied in several types of cells in tissue culture: MCF-7 human breast cancer cells, IM-9 human lymphocytes, human fibroblasts, and H-35 rat hepatoma cells. In none of these cells did the four sulfonylureas tested, tolbutamide, glibenclamide (glyburide), gliclazide, and glisolamide, have any significant effects on insulin binding to its receptor. In contrast the two biguanides tested, phenformin and metformin, increased insulin binding in all cell types by 44 to 101%. These studies raise the possibility, therefore, that biguanides may have a direct effect on insulin receptors and this effect may account for the known effects of biguanides to lower elevated blood sugar levels in diabetic patients.
Diabetes Care
PMID:Effects of biguanides and sulfonylureas on insulin receptors in cultured cells. 673 5


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