Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Choline Deficiency”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources

Effects of ethionine on digestive enzyme synthesis and discharge by mouse pancreas.

The earliest changes noted during the evolution of pancreatitis induced by feeding mice a choline-deficient ethionine-supplemented (CDE) diet are an increase in the number of zymogen granules in pancreatic acinar cells and an increase in digestive enzyme content of the pancreas. We have studied the processes of protein and digestive enzyme synthesis and discharge at varying times after institution of the CDE diet, a choline-deficient diet (CD), and a diet containing ethionine but not choline-deficient (E). Both the CDE and E diets increased digestive enzyme content within 12 h of their institution. Both the CDE and E diets reduced the rate of protein and amylase synthesis and caused a marked reduction in the rate of protein and amylase discharge from the pancreas. These changes were greatest and were noted earliest in the CDE diet group. A marked reduction in secretagogue-induced in vivo and in vitro amylase discharge followed ingestion of either the CDE or E diet. These studies indicate that the increased pancreatic content of digestive enzymes noted after ingestion of the CDE and E diets results from an ethionine-induced decrease in the rat of digestive enzyme discharge. This phenomenon is enhanced by simultaneous choline deficiency. Subsequent intrapancreatic activation of zymogens may couple these changes in enzyme content to the development of hemorrhagic pancreatitis.

Amylases↗

Alterations in nucleotide pools in rats fed diets deficient in choline, methionine and/or folic acid.

The fidelity of DNA synthesis is critically dependent on the correct balance and availability of the deoxynucleoside triphosphate (dNTP) precursors for the polymerases involved in replication and repair. Since folate-derived one-carbon groups are essential for the de novo synthesis of both purines and pyrimidines, the purpose of the present investigation was to determine whether diet-induced depletion of folates would alter intracellular dNTP pools. Fischer 344 rats were fed one of four semi-purified diets for a period of 8 weeks: (i) supplemented control; (ii) deficient in folic acid; (iii) deficient in methionine and choline; and (iv) deficient in methionine, choline and folic acid. In contrast to natural diets, semi-purified diets are nucleotide-free and consequently lack substrates for salvage pathway synthesis. This omission may place unusual stress on folate-dependent de novo nucleotide synthesis especially under conditions of dietary methyl-donor deficiency. Reversed-phase HPLC analysis of dNTP in spleen cell extracts indicated that both the thymidylate monophosphate and thymidylate triphosphate pools were decreased in spleen cells from the deficient rats consistent with a decrease in folate-dependent de novo synthesis. In addition, purine biosynthesis appeared to be negatively affect by methyl-donor deficiency as evidenced by a reduction in dGTP and dATP pools. These data indicate that deoxynucleotide pool imbalance, well known to produce cytogenetic and mutagenic events in vitro, can also be induced in this in vivo model of diet-induced carcinogenesis.

Animals↗

Dietary choline affects response to acetylcholine by isolated urinary bladder.

Age-related increases occur in the response of isolated urinary bladders to the parasympathetic neurotransmitter acetylcholine (ACh). Experiments were carried out to determine whether long-term elevation or diminution in the amount of ingested choline can also affect the response of the urinary bladder to ACh. Female C57BL/6J mice were maintained on a choline-deficient chow and on drinking water supplemented with either 0, 1.5, or 4.0 mg/ml choline chloride from 8 to 20 months of age. Isolated bladders from choline deficient animals showed a 46% increase in the maximum response to ACh as compared to those from normal choline animals, while bladders from animals on choline enriched diets showed a 15% decrease in maximum contractile response. Radioligand binding experiments suggested that the functional changes result from alterations in the density of muscarinic receptors in the bladder. The results are consistent with the hypothesis that muscarinic receptors are down-regulated to compensate for increased parasympathetic activity associated with choline-enriched diets and up-regulated to compensate for decreased parasympathetic activity associated with choline-deficient diets.

Acetylcholine↗

Growth of the skeletal units of the rat mandible in acute renal failure experimental model.

A study of the effect of acute renal failure (ARF) on the growth of the skeletal units of the mandible was performed. Male Wistar rats weighing 35-40 g were assigned to three groups. One of the groups received a basal choline-deficient diet ad libitum. A second group was pair-fed with the first one and was given a basal diet supplemented with 0.35 g choline chloride/100 g of diet. The third group was fed a basal diet plus 0.35 g choline chloride/100 g of diet ad libitum and used as the normal control. Body length, renal function parameters and measurements of the mandible were recorded at the end of a 12-day period on the different diets. Food intake and body weight were recorded every day. Plasma urea and creatinine concentrations markedly increased over the first 12 days of exposure to a choline-deficient diet. Significant increases in urine volume and significant depressions in urine osmolality were also observed. The average body weight and body length gains for rats given the choline-deficient diet were lower than those of control rats. There were no significant differences between the average body weight and body length of pair-fed and normal rats. All skeletal measurements of the mandible of the choline-deficient group differed significantly from those of the control group. These differences varied between 7% and 30%. The skeletal units of the mandible of the pair-fed group did not differ significantly from ad libitum controls. This study suggests that this rat model can be used for the investigation of the different alterations observed in uremia.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗

Abnormal methyl metabolism in pancreatic toxicity and diabetes.

Several experimental studies suggest that disturbed methylation can influence cellular differentiation in the pancreas and contribute to toxic injury in ways that enhance the pathogenesis of pancreatitis and carcinogenesis. In vitro development of fetal rat pancreas requires a basal level of methionine, but full differentiation requires a higher methionine level. Involvement of methylation in normal differentiation is supported by reports of development of hepatocyte-like cells in the pancreas of rats fed a choline-deficient diet. The administration of ethionine by feeding to mice in a choline-sufficient diet caused a lower incidence of acute hemorrhagic pancreatitis than in mice given a choline-deficient diet. Feeding or injections of ethionine in choline-sufficient diets induces low grade pancreatitis and pancreatic atrophy in rats. In the N-nitrosobis(2-oxopropyl)amine-induced model of ductal adenocarcinoma in hamsters, the latent period for induction of carcinomas has been dramatically reduced by the intermittent feeding of a choline-deficient diet combined with ethionine treatment. A recent epidemiologic study in smokers indicates that the risk of pancreatic carcinoma is inverse to serum levels of folate. These studies suggest that compromised methyl metabolism might be associated with pancreatic cancer risk in humans. Finally, it has recently been demonstrated that serum homocysteine and erythrocyte S-adenosylhomocysteine levels are elevated, and erythrocyte S-adenosylmethionine content is reduced in patients with diabetes mellitus and renal failure, likely reflecting disturbed methylation pathways. The latter may contribute to the pathogenesis of complicating lesions in diabetes. These studies suggest that disturbed methyl metabolism may contribute to the pathogenesis of several pancreatic diseases.

Animals↗

Vitamin B2 metabolism in the isolated perfused rat liver.

An investigation on vitamin B2 (V.B2) metabolism was undertaken, using perfused livers isolated from 1. normal rats, 2. riboflavin deficient rats, 3. choline deficient rats with fatty cirrhtic livers, and 4. alloxan diabetic rats, without the effect of extrahepatic factors. From the results, it was concluded that phosphorylation of V.B2 was performed in the liver, and was remarkably reduced in fatty cirrhosis. Moreover, in alloxan diabetic liver, the affected phosphorylation of V.B2 was improved by the infusion of insulin. The important role that liver performs on V.B2 metabolism, can be emphasized from these findings.

Animals↗

Helicobacter pylori infection induces hyperammonaemia in Mongolian gerbils with liver cirrhosis.

BACKGROUND AND AIMS: We previously reported the effect of Helicobacter pylori eradication on hyperammonaemia in patients with liver cirrhosis. However, the role of H pylori as a cause of hyperammonaemia is controversial. We developed an animal model with liver cirrhosis and investigated the effect of H pylori infection on hyperammonaemia. MATERIALS AND METHODS: Five week old male Mongolian gerbils were inoculated orally with broth culture of H pylori. Forty eight gerbils were divided into four groups. Gerbils not inoculated with H pylori were fed a commercial rodent diet (group A) or a choline deficient diet (group C). Gerbils inoculated with H pylori were fed the commercial rodent diet (group B) or the choline deficient diet (group D). Blood ammonia levels of the femoral vein and portal vein were measured 30 weeks later. RESULTS: All gerbils fed the choline deficient diet developed liver cirrhosis with fatty metamorphosis. The survival rate of group D was significantly lower than that of the other groups. Systemic and portal blood ammonia levels in group D were significantly higher than those in the other groups. CONCLUSIONS: H pylori infection induces hyperammonaemia in gerbils with liver cirrhosis.

Animals↗

Verbal and visual memory improve after choline supplementation in long-term total parenteral nutrition: a pilot study.

BACKGROUND: Previous investigations have demonstrated that choline deficiency, manifested in low plasma-free choline concentration and hepatic injury, may develop in patients who require long-term total parenteral nutrition (TPN). Preliminary studies have suggested lecithin or choline supplementation might lead to improved visual memory in the elderly and reverse abnormal neuropsychological development in children. We sought to determine if choline-supplemented TPN would lead to improvement in neuropsychological test scores in a group of adult, choline-deficient outpatients receiving TPN. METHODS: Eleven subjects (8 males, 3 females) who received nightly TPN for more than 80% of their nutritional needs for at least 12 weeks before entry in the study were enrolled. Exclusion criteria included active drug abuse, mental retardation, cerebral vascular accident, head trauma, hemodialysis or peritoneal dialysis, (prothrombin time [PT] >2x control), or acquired immune deficiency syndrome (AIDS). Patients were randomly assigned to receive their usual TPN regimen (n = 6, aged 34.0 +/- 12.6 years) over a 12-hour nightly infusion or their usual TPN regimen plus choline chloride (2 g) (n = 5, aged 37.3 +/- 7.3 years). The following neuropsychological tests were administered at baseline and after 24 weeks of choline supplementation (or placebo): Weschler Adult Intelligence Scale-Revised (WAIS-R, intellectual functioning), Weschler Memory Scale-Revised (WMS-R, two subtests, verbal and visual memory), Rey-Osterrieth Complex Figure Test (visuospatial functioning and perceptual organization), Controlled Oral Word Association Test (verbal fluency), Grooved Pegboard (manual dexterity and motor speed), California Verbal Learning Test (CVLT, rote verbal learning ability), and Trail Making Parts A & B (visual scanning, psychomotor speed and set shifting). Scores were reported in terms of standard scores including z scores and percentile ranks. Mean absolute changes in raw scores were compared between groups using the Wilcoxon rank sum test, where p values < .05 constituted statistical significance. RESULTS: Significant improvements were found in the delayed visual recall of the WMS-R (7.0 +/- 2.7 vs -.33 +/- 5.7, p = .028), and borderline improvements in the List B subset of the CVLT (1.0 +/- 0.8 vs -2.0 +/- 2.4, p = .06) and the Trails A test (-3.8 +/- 8.1 vs 3.7 +/- 4.5 seconds, p = .067). No other statistically significant changes were seen. CONCLUSIONS: This pilot study indicates both verbal and visual memory may be impaired in patients who require long-term TPN and both may be improved with choline supplementation.

Adult↗

Prolonged fasting in humans results in diminished plasma choline concentrations but does not cause liver dysfunction.

Choline is a major donor of methyl groups, a precursor for membrane synthesis, and a component of the neurotransmitter acetylcholine. Choline-deficient diets deplete humans of choline and cause hepatic dysfunction and steatosis. In this study we determined whether acute starvation also depletes choline, as indicated by changes in plasma choline or phosphatidylcholine. Healthy humans (n = 10) fasted for 7 d, ingesting only water and mineral-vitamin supplements. Their mean (+/- SEM) plasma choline concentration was 9.5 +/- 0.5 micromol/L at the start of the study and dropped to 7.8 +/- 0.3 micromol/L after 1 wk of fasting (P < 0.01). The plasma phosphatidylcholine concentration did not change significantly (2.2 +/- 0.1 mmol/L at the start of the study and 2.4 +/- 0.2 mmol/L after 1 wk of fasting). Capacity of the liver to secrete lipoproteins was not affected by prolonged fasting. The mean plasma concentration of low-density-lipoprotein cholesterol was 3.3 +/- 0.2 mmol/L (126 +/- 8 mg/dL) at the start of the study and 4.9 +/- 0.5 mmol/L (188 +/- 19 mg/dL) after 1 wk of fasting. Liver damage assessed by serum alanine aminotransferase activity occurred in only 1 of 10 subjects. We conclude that prolonged fasting in humans modestly diminished plasma choline but was not associated with signs of choline deficiency, such as perturbed lipoprotein secretion and liver damage.

Adult↗

Head group specificity in the regulation of phosphatidylcholine catabolism in rat hepatocytes.

Previous studies have shown that the catabolism of PC is regulated in choline-deficient hepatocytes and the concentration of phosphatidylcholine (PC) might be an important regulatory factor (Tijburg, L.B.M., Nishimaki-Mogami, T. and Vance, D.E. (1991) Biochim. Biophys. Acta, 1085, 167-177). In the present study we investigated the head group specificity of the regulation of PC catabolism. Supplementation of choline-deficient rat hepatocytes, prelabeled with [3H]choline, with dimethylethanolamine increased the catabolism of PC by 1.6-fold after 6 h. This effect was accompanied by a 2.5-fold increase in the production of [3H]glycerophosphocholine (GPC). Radioactivity associated with lysoPC was decreased by 50% in dimethylethanolamine-treated cells. Supplementation of the cells with monomethylethanolamine had little effect on the degradation of PC. In other experiments choline-deficient cells were prelabeled with [3H]methionine. Treatment of the cells with dimethylethanolamine increased the formation of [3H]GPC by 5-fold, while the production of lysoPC was inhibited by 60%. Supplementation of the medium with monomethylethanolamine resulted in a 2-fold increase in labeled GPC, with a concomitant decrease of [3H]lysoPC by approx. 25%. We conclude that the formation of phosphatidyldimethylethanolamine from its corresponding base mimics the effect of the synthesis of PC from choline in increasing PC catabolism, whereas the effect of monomethylethanolamine is much less pronounced.

Animals↗

The effects of N-acetylcysteine and anti-intercellular adhesion molecule-1 monoclonal antibody against ischemia-reperfusion injury of the rat steatotic liver produced by a choline-methionine-deficient diet.

Abundant fat in the liver has been implicated in poor outcome after liver transplantation or liver surgery, but the reasons for this association are still unclear. The aim of the present study was to examine mechanisms that may be involved in hepatic dysfunction after ischemia-reperfusion (I/R) of the steatotic rat liver. Steatosis was produced by a choline-methionine-deficient (CMDD) diet. In the first experiment, isolated perfused rat livers, subjected to 24-hour cold storage followed by 120-minute reperfusion, were used to investigate hypothermic I/R injury of the steatotic rat liver. In the second experiment, livers were subjected to 60-minute partial left lobar vascular clamping to allow study of normothermic I/R injury. In the first experiment, compared with normal nonsteatotic liver, steatotic livers showed significantly greater injury, as assessed by amounts of hepatic enzymes released into the perfusate, bile production, the concentrations of reduced glutathione (GSH) in the perfusate, as well as in the livers themselves, and electron microscopic findings of sinusoidal microcirculatory injury. The addition of N-acetylcysteine (NAC), a precursor of glutathione, to the liver before cold storage significantly improved these parameters in steatotic livers. The second experiment showed that, compared with nonsteatotic livers, steatotic livers had lower concentrations of GSH and impaired rates of bile production. There was also evidence of increased oxidative stress in polymorphonuclear leukocytes (PMNLs) in liver or peripheral blood of rats with fatty livers. An anti-rat intercellular adhesion molecule-1 (ICAM-1) monoclonal antibody inhibited neutrophil infiltration into pericentral sinusoids and improved these parameters in the steatotic rats. We conclude that sinusoidal microcirculatory injury is involved in hypothermic I/R injury, that oxidative stress produced by PMNLs is involved in normothermic I/R injury, and that NAC and anti-rat ICAM-1 monoclonal antibody restore liver integrity in I/R injury.

Acetylcysteine↗

Influence of dietary choline availability and neuronal demand on acetylcholine synthesis by rat brain.

The main objective of this study was to test the hypothesis that the chronic administration of choline supplements a bound pool of choline from which free choline can be mobilized and used to support acetylcholine synthesis when the demand for precursor is increased. For these experiments, brain slices from rats fed diets containing different amounts of choline were incubated in a choline-free buffer and acetylcholine synthesis was measured under resting conditions and in the presence of K+-induced increases in acetylcholine synthesis and release. Rats fed the choline-supplemented diet had circulating choline levels that were 52% greater than the controls, and striatal and cerebral cortical slices from this group produced significantly more free choline during the incubation than slices from the controls. However, the synthesis and release of acetylcholine by these tissues did not differ from those by controls, during either resting or K+-evoked conditions. In contrast, acetylcholine synthesis and release by striatal and hippocampal slices from choline-deficient rats, animals that had circulating choline levels that were 80% of control values, decreased significantly; the production of free choline by these tissues was also depressed. Results indicate that, despite an increased production of free choline by brain slices from choline-supplemented rats, the synthesis of acetylcholine was unaltered, even in the presence of an increased neuronal demand. In contrast, the choline-deficient diet led to a decreased release of free choline from bound stores and an impaired ability of brain to synthesize acetylcholine.

Acetylcholine↗

Head group specificity in the requirement of phosphatidylcholine biosynthesis for very low density lipoprotein secretion from cultured hepatocytes.

We have demonstrated that hepatic very low density lipoprotein (VLDL) secretion requires active phosphatidylcholine (PC) synthesis via either the CDP-choline pathway or phosphatidylethanolamine (PE) methylation pathway (Yao, Z., and Vance, D.E. (1988) J. Biol. Chem. 263, 2998-3004). In the present work, the head group specificity of phospholipid synthesis required for lipoprotein secretion was investigated in cultured hepatocytes isolated from choline-deficient rats. When N-monomethylethanolamine (0.1 mM) or N,N-dimethylethanolamine (0.1 mM) was added to the culture medium, the cells synthesized correspondingly phosphatidylmonomethylethanolamine (PMME) or phosphatidyldimethylethanolamine (PDME). However, the synthesis of PDME could correct the impaired VLDL secretion only to a limited extent, whereas the synthesis of PMME inhibited VLDL secretion. Although dimethylethanolamine did not promote VLDL secretion as well as choline, dimethylethanolamine altered the increased triacylglycerol synthesis in the choline-deficient cells as effectively as choline. Supplementation of the culture medium with ethanolamine (0.1 mM) had little effect on cellular PE or PC levels, nor was normal VLDL secretion resumed. However, the amounts of cellular PC and PE were both decreased when the medium was supplemented with N-monomethylethanolamine or N,N-dimethylethanolamine. These results suggest that the choline head group moiety of PC is specifically required for normal VLDL secretion and cannot be replaced with ethanolamine, monomethylethanolamine, or dimethylethanolamine. In addition, the impaired VLDL secretion from the choline-deficient hepatocytes could also be corrected by supplementation of betaine (0.2 mM) and homocysteine (0.2 mM), indicating the utilization of a methyl group from betaine for PC formation via methylation of PE.

Animals↗

Differential expression of hepatocyte growth factor, transforming growth factor-alpha and transforming growth factor-beta 1 messenger RNAs in two experimental models of liver cell proliferation.

Hepatocyte growth factor, a potent hepatocyte mitogen in vitro, appears to trigger hepatocyte regeneration after partial hepatectomy and after acute liver cell necrosis. Transforming growth factor-alpha and transforming growth factor-beta 1 may also be involved in the control of liver regeneration. In this study we assessed possible roles of hepatocyte growth factor, transforming growth factor-alpha and transforming growth factor-beta 1 on liver cell proliferation in vivo, using a model of choline deficiency that is associated with liver cell necrosis and a model of a hypolipidemic agent (4-chloro-6-(2,3 xylidino)-2-pyrimidinylthio (N-beta-hydroxyethyl) acetamide) without liver necrosis. Male F344 rats were fed a choline-deficient diet or 0.16% 4-chloro-6-(2,3 xylidino)-2-pyrimidinylthio (N-beta-hydroxyethyl) acetamide diet for 6 and 4 wk, respectively. Rats were killed periodically, and the expression of hepatocyte growth factor messenger RNA in the liver, lung and kidney was determined by Northern-blot analysis. The levels of transforming growth factor-alpha and transforming growth factor-beta 1 messenger RNAs in the liver were also determined. Feeding a choline-deficient diet for 1 to 6 wk led to gradual increases in the levels of hepatocyte growth factor, transforming growth factor-alpha and transforming growth factor-beta 1 messenger RNAs in the liver. Feeding a 4-chloro-6-(2,3 xylidino)-2-pyrimidinylthio (N-beta-hydroxyethyl) acetamide diet for 3 days and 2 wk induced marked enhancement of liver cell proliferation as judged by hepatocyte 5-bromo-2-deoxyuridine incorporation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Prenatal choline exposure alters hippocampal responsiveness to cholinergic stimulation in adulthood.

Manipulation of dietary choline levels during gestation results in enduring neurobehavioral changes in offspring that last into adulthood. Alterations of hippocampal function and memory are among the most striking changes. Depending upon the measures assessed, prenatal choline supplementation tends to promote excitatory synaptic efficacy in hippocampal circuits while prenatal choline deficiency diminishes it. However, the mechanisms underlying these changes remain unclear. Transverse hippocampal slices were prepared from adult offspring of dams fed choline supplemented, choline deficient, or control diets. We assessed paired-pulse inhibition, and excitatory synaptic responsiveness before and after activation of cholinergic receptors with Carbachol. Prenatally choline deficient animals yielded significantly fewer electrophysiological viable hippocampal slices than did animals from either of the other two treatment groups. Among the slices tested, there were no differences in paired pulse inhibition between the treatment groups. However, transient cholinergic activation resulted in a prolonged enhancement of the amplitude of the population EPSP (pEPSP) response in slices from prenatally choline supplemented animals. These results suggest that GABA receptor-mediated inhibition remains intact after prenatal choline manipulations, and that enhancement of the excitatory responsiveness of hippocampal circuits in slices from prenatally choline supplemented rats may be related in part to an increase in cholinergic tone within the CA1 circuit.

Animals↗

Mouse livers with macrosteatosis are more susceptible to normothermic ischemic injury than those with microsteatosis.

BACKGROUND/AIMS: Fatty livers are increasingly used for transplantation due to the dramatic organ shortage. While steatosis is an established risk factor for post-operative complications, the impact of macro- vs. microvesicular steatosis on ischemic injury is unclear. METHODS: The effects of ischemia and reperfusion were tested in two different models of steatotic mice: ob/ob as a model disclosing predominantly macrovesicular steatosis and choline deficient diet having mainly microvesicular steatosis. Steatotic and lean livers were subjected to 45 min of ischemia. Serial markers of hepatocellular injury, animal survival were measured. Hepatic tissue blood flow and portal vein perfusion were assessed. RESULTS: Ob/ob mice had a significantly lower tolerance to hepatic ischemia. with increased AST release and decreased survival in comparison to the choline deficient mice. No difference in ATP content was found between both steatosis models, but hepatic perfusion and portal vein flow were significantly lower after reperfusion in the ob/ob mice when compared to the choline deficient animals. Ischemic pre-conditioning significantly improved liver reperfusion and injury in both models of steatosis. CONCLUSIONS: Livers with macrovesicular steatosis have a lower tolerance to ischemic injury than those with microvesicular steatosis. Low intrahepatic and portal vein perfusion in macrovesicular fatty livers is, at least partially, responsible for the poorer outcome.

Adenosine Triphosphate↗