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PubMed1985

The role of the kidney in the elimination of pancreatic lipase and amylase from blood.

Two clinical observations indicate that the kidney plays the main role in the elimination of lipase and amylase from the circulation: 1. in patients with uncomplicated acute pancreatitis the decrease of the activity of both enzymes in the serum ran almost in parallel. The half life for lipase was found to be 6.9-13.7 h, and somewhat higher figures (9.3-17.7 h) were calculated for amylase; 2. in patients with reduced glomerular filtration rate the serum activity of either or of both enzymes was distinctly elevated. The contribution of the kidney to the elimination of lipase and amylase from blood was studied in the rat. After an intravenous bolus injection of homologous lipase and amylase, the serum activity of both enzymes decreased rapidly. The half-life of lipase was 18.1 min, that of amylase 20.5 min. Up to 30% of the injected amylase but only traces of lipase activity were recovered in the urine. In animals with ligated kidneys the serum half-life of both enzymes was 3 times longer. Our results indicate that lipase as well as amylase are removed from the serum mainly by glomerular filtration at nearly the same rate. Reabsorption of lipase is almost complete, in contrast to that of amylase. It is suggested that the differences in the renal handling of both enzymes are due to their differing affinities for hydrophilic and hydrophobic surfaces.

Acute Disease↗
PubMed1987

Macro lipase--a new member of the family of immunoglobulin-linked enzymes.

This first report describes a variant form of lipase in the serum of a woman suffering from a malignant non-Hodgkin lymphoma. Activity measurements of serum lipase and amylase showed persistently elevated activities of lipase with simultaneously normal activities of amylase. Results of exclusion chromatography and immunological investigations clearly demonstrate that the atypical time-course of lipase activity is not due to injury of the pancreas or alterations of the patient's lipase, but rather due to the presence of lipase-binding autoantibodies, resulting in the formation of immune complexes with high molecular mass (Mr greater than 200,000) between lipase and immunoglobulin G lambda. A clinical significance, if any, of this macro lipase has yet to be determined.

Antigen-Antibody Complex↗
PubMed1988

Renal handling of 125I-labelled homologous pancreatic lipase and amylase in the rat.

Experiments were carried out in vivo on rats and in vitro on tubular brush border vesicles in order to study the renal mechanisms of the elimination of pancreatic lipase and amylase from the circulation. Highly purified 125I-labelled homologous lipase, amylase or 125I-labelled di-iodo-tyrosine was injected intravenously in a single dose. The sieving coefficients of lipase and amylase were found to be 0.126 and 0.118 respectively. Less than 1% of the lipase activity but more than 10% of the radioactivity were found in the urine in the course of a 120 min experiment. In experiments with amylase, 16% of the enzyme activity and 19% of the radioactivity were present in the urine. Elimination of both enzymes showed first order kinetics and was of the same magnitude (17-24 min). The elimination curves of the radioactivity consisted of at least two components: a fast component immediately after the injection, which was identical with the decrease of the resp. enzyme activity; and a slow component (half-life 106 min), which in both cases proved to be identical with the half-life of di-iodo-tyrosine. In experiments with amylase, the excretion of protein-free 125I-activity started later than with lipase. The radioactivity of 125I-labelled lipase was taken up faster by brush-border-vesicles than that of 125I-amylase. Liberation of protein-free 125I-activity from both enzymes occurred at the same rate. At the end of the experiments the kidneys had no lipase or amylase activity, but they contained 5.4% (lipase), 3.8% (amylase) of the injected radioactivity.(ABSTRACT TRUNCATED AT 250 WORDS)

Amylases↗
PubMed2004

Properties of an immobilized lipase of Bacillus coagulans BTS-1.

Lipase (EC 3.1.1.3) is a tri-acylglycerol ester hydrolase, catalysing the hydrolysis of tri-, di-, and mono-acylglycerols to glycerol and fatty acids. To study the effect of adsorption of a lipase obtained from Bacillus coagulans BTS-1, its lipase was immobilized on native and activated (alkylated) matrices, i.e. silica and celite. The effect of pH, temperature, detergents, substrates, alcohols, organic solvent etc. on the stability of the immobilized enzyme was evaluated. The gluteraldahyde or formaldehyde (at 1% and 2% concentration, v/v) activated matrix was exposed to the Tris buffered lipase. The enzyme was adsorbed/entrapped more rapidly on to the activated silica than on the activated celite. The immobilized lipase showed optimal activity at 50 degrees C following one-hour incubation. The lipase was specifically more hydrolytic to the medium C-length ester (p-nitro phenyl caprylate than p-nitro phenyl laurate). The immobilization/entrapment enhanced the stability of the lipase at a relatively higher temperature (50 degrees C) and also promoted enzyme activity at an acidic pH (pH 5.5). Moreover, the immobilized lipase was quite resistant to the denaturing effect of SDS.

Bacillus↗
PubMed2004

[Validity of serum amylase and lipase in the differential diagnosis between acute/acutized chronic pancreatitis and other causes of acute abdominal pain].

BACKGROUND: Raised serum amylase and lipase levels are observed in several abdominal diseases. AIM: Assessing the validity of serum amylase and lipase for the differential diagnosis between acute pancreatitis/acutized chronic pancreatitis, biliary tract disease, perforated gastroduodenal ulcer and acute appendicitis. PATIENTS E METHODS: Prospective study including 134 individuals: 38 with acute pancreatitis/acutized chronic pancreatitis, 35 with biliary tract disease, 17 with perforated gastroduodenal ulcer and 44 with acute appendicitis, mean age (standard deviation) of 42.4 +/- 17.7, 46.7 +/- 18.3, 47.8 +/- 12 and 33.7 +/- 17.8 years, respectively. Serum amylase and lipase were determined at admission to the emergency department. RESULTS: For the diagnosis of acute pancreatitis/acutized chronic pancreatitis, when the cutt-off levels of serum amylase were set at the upper normal range level or up to 5-fold as high, the sensitivity decreased from 92% to 74%, the specificity increased from 85% to 99%, the positive predictive value increased from 71% to 97%, and the negative predictive value decreased from 96% to 91%. For serum lipase levels similar figures were obtained for sensitivity and negative predictive value, but the specificity and positive predictive value were lower. When the combination of raised serum amylase or lipase were analyzed, a minor increase was observed in sensitivity and negative predictive value. CONCLUSIONS: For the diagnosis of acute pancreatitis/acutized chronic pancreatitis: 1) the best cut-off level for both tests was 2-times the upper normal range; 2) the sensitivities of serum amylase and lipase were similar; 3) the specificity and positive predictive value of serum amylase were slightly higher than observed for serum lipase; 4) the sensitivity but not the specificity increased when at least one between amylase or lipase was raised.

Abdominal Pain↗
PubMed2001

The influence of fasting/refeeding on the lipoprotein lipase activity of adipose tissue and muscle.

Lipoprotein lipase activity in adipose tissue and muscle is modulated by changes in the pattern of food intake. We have measured total lipoprotein lipase activity in adipose tissue and muscle of male Wistar rats (N = 6-10), weighing 200-250 g (~12 weeks), during the refeeding/fasting state following 24 h of fasting. Lipoprotein lipase activity in tissue homogenates was evaluated using a [3H]-triolein-containing substrate, and released [3H]-free fatty acids were extracted and quantified by liquid scintillation. Adipose tissue lipoprotein lipase activity did not completely recover within 2 h of refeeding (60% of refed ad libitum values). Cardiac lipoprotein lipase activity remained increased even 2 h after refeeding (100% of refed ad libitum values), whereas no significant changes were observed in the soleus and diaphragm muscles. Adipose tissue lipoprotein lipase activities were consistently higher than the highest skeletal muscle or heart values. It is therefore likely that adipose tissue, rather than muscle makes the major contribution to triacylglycerol clearance. There was concomitant relatively high lipoprotein lipase activity in both adipose tissue and cardiac muscle during the first few hours of refeeding, therefore cardiac muscle may contribute significantly to triacylglycerol clearance during this period. The results suggest that during fasting, increased lipoprotein lipase activity provides a complementary source of free fatty acids from circulating triacylglycerol, allowing the heart to maintain its continuous, high-energy expenditure.

Adipose Tissue↗
PubMed1990

Effect of weaning, week postweaning and diet composition on pancreatic and small intestinal luminal lipase response in young swine.

The effects of weaning, week postweaning and diet composition on concentration of lipase in the pancreas and small intestinal lumen were investigated in weanling swine. In Exp. 1, lipase levels were evaluated in suckling pigs from 2 to 35 d of age and in pigs weaned at 21 or 35 d of age. Pigs weaned at 21 d of age were fed a corn-soybean meal diet with lipase levels measured from 3 to 28 d postweaning. Pancreas weights increased during the suckling period; they were lowered at 3 d postweaning and were lower at 7 d postweaning than in suckling pigs but increased linearly from 3 to 28 d postweaning. Lipase level per unit wet tissue and total pancreatic levels increased from 2 to 35 d of age in suckling pigs (P less than .01). Weaning at 21 d of age resulted in a decline (P less than .05) in lipase levels in the pancreas at 3 and 7 d postweaning, but the levels subsequently tended to increase between 7 and 28 d postweaning. Whereas relative lipase levels in the intestinal lumen increased from 2 to 35 d of age in suckling pigs, total luminal enzyme did not decline upon weaning when pigs were weaned at either 21 or 35 d of age. Total luminal lipase per unit empty body increased linearly (P less than .01) each week postweaning. In Exp. 2, a 2 X 2 factorial arrangement of corn oil (0 or 6%) and dried whey (0 or 25%) was used to evaluate digestive lipase levels in pigs weaned at 21 d of age.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1994

Pseudomonas lipases: molecular genetics and potential industrial applications.

Lipases are esterases able to hydrolyze water-insoluble esters such as long-chain triglycerides. These enzymes also catalyze the formation of esters (esterification) and the exchange of ester bonds (transesterification) when present in nonaqueous media. Lipases display a high degree of specificity and enantioselectivity for esterification and transesterification reactions, and thus their potential uses in industry are very wide. These potential industrial applications have been an important driving force for lipase research during the last several years, and in particular for the study of lipases produced by microorganisms. Pseudomonas lipases are very interesting because they display special biochemical characteristics not common among the lipases produced by other microorganisms, such as their thermoresistance and activity at alkaline pHs. Recently, several Pseudomonas genes have been cloned and sequenced, and the regulation of their expression is beginning to be understood. The molecular genetic approach to the study of Pseudomonas lipases will permit the construction of recombinant strains with increased lipase productivity and will provide the opportunity to modify these enzymes to suit particular industrial applications.

Biotechnology↗
PubMedDate not supplied

Variation of gastric lipase secretion in the Heidenhain pouch of the cat.

In the cat, gastric lipase secretion was equally but weakly stimulated by pentagastrin, a major stimulant of acid secretion, and by carbamylcholine, a major stimulant of pepsin secretion. Lipase was also stimulated by fresh liver, which induces a large blood gastrin release and not by canned food, which is a poor gastrin releaser. Lipase output always preceded that of acid an pepsin. Lipase was not correlated with acid and pepsin secretion while acid and pepsin were well correlated during all stimulations but not in basal state. Lipase is co-localized with pepsin in the chief cells but is also present in pepsin-free cells, the mucus surface cells of the fundus and the antrum. The distribution of lipase explains the lack of correlation between pepsin and lipase as already mentioned. However, our data show that lipase secretion is under the control of gastric stimulants and might play a role in the gastric initiation of pancreatic meal lipolysis.

Animals↗
PubMedDate not supplied

Cholinergic and pentagastrin stimulation of the gastric secretions of acid, pepsin and lipase in the awake rabbit.

Acid, pepsin and lipase secretions were simultaneously studied in awake rabbits with a Heidenhain pouch during cholinergic (carbamylcholine 20 micrograms.kg-1 x h-1) or maximal pentagastrin stimulation (64 mu.kg-1 x h-1). To avoid lipase inactivation by low pH, the pouch was perfused at a constant pH, with a solution irrigating the pouch without inducing any pressure. Acid and pepsin outputs were equally activated by both stimulants. Lipase output was stimulated much more by pentagastrin (x26) than by carbamylcholine (x6). The maximal lipase output preceded that of acid output. Lipase concentration increased in the gastric juice whereas pepsin concentration remained constant. A negative correlation was calculated between acid and lipase or pepsin and lipase output. A positive correlation was obtained between acid and pepsin. Our data show that pepsin and lipase secretions which come from distinct chief cells, in the rabbit, responded to the same stimulants but with quantitative and timing differences.

Animals↗
PubMed1982

Effect of exogenous estradiol and progesterone upon lipase activity and spontaneous lipolysis in bovine milk.

Three of six lactating Jersey cows received estradiol--17 beta and progesterone (.10 and .25 mg/kg body weight per day subcutaneously for 7 consecutive days. Lipase activity and acid degree were determined for morning milk samples stored 24 h at 4 degrees C. Whole milk lipase activity did not increase over control milk samples; however, lipase activity of cream fraction and percent whole milk lipase activity in cream fraction increased 200 and 100%. Increases in acid degree occurred also and were closely correlated (.8 to .9) with lipase activity of cream fraction and percent whole milk lipase activity in cream fraction. Cooling was not required to effect association of lipase with cream fraction. Two treated cows developed mastitis-like symptoms after elevation in lipase activity of cream fraction and acid degree. Estradiol alone evoked similar responses.

Animals↗
PubMed1992

Developmental delay of lingual lipase expression after guanethidine-induced sympathectomy.

Rat lingual lipase increases during postnatal development. To evaluate the role of the sympathetic nervous system in the control of lingual lipase during development, suckling rats were chemically sympathectomized by chronic treatment with guanethidine. This treatment was found to be effective in suppressing the developmental increase of lingual lipase. The effect was age dependent and also related to the dose of guanethidine given (i.e., the higher the dose, the more effective the suppression is, up to 40 micrograms/g body wt). The effect of guanethidine on lingual lipase suppression was not a result of induced stress, since simultaneous treatment with RU-38486, a known glucocorticoid receptor antagonist, did not prevent the decrease in lingual lipase activity. Ephedrine, a known sympathomimetic agent, restored the lingual lipase to a near normal level in guanethidine-treated animals, confirming that guanethidine acts through the sympathetic nerves. Furthermore, histochemical studies showed that guanethidine-treatment resulted in the reduction or elimination of catecholaminergic fibers in the von Ebner's glands. The effect of guanethidine was found to be transient, in that the lingual lipase activity showed complete recovery upon withdrawal of the treatment for 1 week. Together, the results indicated that sympathetic nerves have an important regulatory role in lingual lipase in rat pups during development.

Age Factors↗
PubMed1999

Purification and characterization of a Pseudomonas sp. lipase and its properties in non-aqueous media.

An extracellular lipase from Pseudomonas sp. was purified to homogeneity by extraction, Bio-gel P-10 chromatography and Superose 12B chromatography, and a 37-fold purification was attained. The purified enzyme showed a single band when it was subjected to SDS/PAGE and isoelectric focusing. The SDS/PAGE electrophoresis indicated a molecular mass of 30 kDa for this lipase. Its isoelectric point was 4.5. The optimum pH and temperature for hydrolysis were 7.0-9.0 and 45-60 degrees C, respectively. The enzyme was stable between pHs 6 and 12 and below 60 degrees C. In the presence of Ca(2+) and Bi(3+), the lipase activity was dramatically enhanced by 250% and 154%, respectively. Fe(3+), Fe(2+), Al(3+), Zn(2+) and Mn(2+) could inhibit this lipase, but Ag(+) and Pb(2+) showed no influence on hydrolysis activity. Properties of purified lipase for lactonization in organic solvent were also determined. The purified lipase displayed the characteristic of 'pH memory' in organic media. This lipase was also thermostable in organic solvent with an optimum temperature range from 45 to 60 degrees C. Salt dramatically affected the lactonization activity of this lipase.

Chromatography, Ion Exchange↗
PubMedDate not supplied

Comparison of urine trypsinogen-2 test strip with serum lipase in the diagnosis of acute pancreatitis.

BACKGROUND/AIMS: The accuracy of a new rapid urinary trypsinogen-2 test strip (actim Pancreatitis) was compared with that of serum lipase for detection of acute pancreatitis in patients with acute abdominal pain. METHODOLOGY: A prospective study was conducted which consisted of 237 consecutive patients with acute abdominal pain admitted to the emergency unit at Helsinki University Central Hospital. The patients were tested on admission with the actim Pancreatitis test strip. Serum amylase, serum lipase, and urine trypsinogen-2 concentrations were also determined quantitatively. RESULTS: The actim Pancreatitis test strip result was positive in 27 out of 29 patients with acute pancreatitis (sensitivity 93%) and in 16 of 208 patients with non-pancreatic abdominal pain (specificity 92%). This was superior to that of serum lipase (sensitivity 79% and specificity 88%). With a cut-off > 3x the upper reference limit, the sensitivity of serum lipase was only 55% while the specificity was 99%. The high sensitivity for the actim Pancreatitis test strip resulted in a very high negative predictive value of 99%. All six patients with severe acute pancreatitis were detected by the dipstick. With a higher cut-off value (> 3x upper reference limit) for lipase, two patients with severe acute pancreatitis remained undetected. Combining the actim Pancreatitis dipstick with serum lipase a positive predictive value of 94% was obtained. CONCLUSIONS: Acute pancreatitis can be excluded with a higher probability with the actim Pancreatitis strip than with serum lipase determination, and therefore appears to be more suitable for screening of acute pancreatitis. With its high specificity with a cut-off > 3x the upper reference limit, serum lipase is suitable as a confirmatory test for pancreatitis when a positive dipstick result is obtained.

Abdominal Pain↗
PubMed1991

Lipase activity in serum measured with Ektachem is often increased in nonpancreatic disorders.

For patients with symptoms of pancreatitis, measurement of amylase in serum reportedly is more sensitive than that of lipase in acute pancreatitis, whereas lipase reportedly is more specific. However, serum lipase activities exceeding the upper reference limit (URL) have been reported for many patients who did not have pancreatitis. I reviewed the serum lipase and amylase concentrations of 493 consecutive inpatients and emergency department patients for whom both tests were ordered. Serum lipase and amylase activities, determined with an Ektachem 700 analyzer, were less than or equal to URL for 390 patients (83%) and greater than URL for 103. Medical records of 101 of these 103 were reviewed; 18 had acute or chronic relapsing pancreatitis. In this latter group, serum lipase values greater than URL had 100% sensitivity and 84% specificity; those of serum amylase greater than URL had 72% sensitivity and 88% specificity. However, the test combination of serum lipase greater than URL and serum amylase less than or equal to URL also occurred in 84% of the patients in which review of the medical records revealed nonpancreatic gastrointestinal or hepatobiliary disorders as the primary problem (n = 55). Therefore, serum lipase activity measured with the Ektachem assay is also often increased in patients with intra-abdominal disorders that appear to be nonpancreatic.

Amylases↗
PubMed1990

Secretion of rat hepatic lipase is blocked by inhibition of oligosaccharide processing at the stage of glucosidase I.

Rat hepatic lipase is a glycoprotein bearing two N-linked oligosaccharide chains. The importance of glycosylation in the secretion of hepatic lipase was studied using freshly isolated rat hepatocytes. Various inhibitors of oligosaccharide synthesis and processing were used at concentrations that selectively interfere with protein glycosylation. Secretion of hepatic lipase activity was abolished by tunicamycin, castanospermine, and N-methyldeoxynojirimycin. No evidence was found by ELISA or Western blotting for secretion of inactive protein. Inhibition of secretion became apparent after a 30-min lag, corresponding to the time of intracellular transport of pre-existing protein. Simultaneously, intracellular hepatic lipase activity ws depleted. Secretion of hepatic lipase protein and activity was not affected by deoxymannojirimycin and swainsonine. Upon SDS-polyacrylamide gel electrophoresis, hepatic lipase secretion by deoxymannojirimycin- or swainsonine-treated cells showed an apparent Mr of 53 kDa and 55 kDa, respectively, which was distinct from hepatic lipase secreted by untreated cells (Mr = 58 kDa). We conclude that glycosylation and subsequent oligosaccharide processing play a permissive role in the secretion of hepatic lipase. As secretion is prevented by the glucosidase inhibitors castanospermine and N-methyldeoxynojirimycin, but not by inhibitors of subsequent oligosaccharide trimming, the removal of glucose residues from the high-mannose oligosaccharide intermediate in the rough endoplasmic reticulum appears the determining step.

1-Deoxynojirimycin↗
PubMed1990

Macrolipasemia: a rare cause of persistently elevated serum lipase.

This report describes a variant form of lipase found in a patient with cryptogenic liver cirrhosis. Serum lipase in this patient showed persistently increased activity with simultaneously normal activity of amylase. Results of exclusion chromatography demonstrate that the lipase activity in the serum of this patient eluted as a macromolecule. Since macromolecular complexes were not fixed by protein A, it seems unlikely that lipase is attached to IgG. Tests of the sera from 20 patients with raised serum lipase activity in acute pancreatitis or an acute episode of chronic pancreatitis revealed, in two patients, that a small but reproducible proportion of the total lipase activity eluted in the region of the macrolipase. In addition, 10% and 18% of the total lipase activity was found in the elution region of the macrolipase in two commercial pooled sera used for quality control. The results show that, in rare cases, macrolipasemia must be considered a possible cause of raised serum lipase activity.

Aged↗
PubMed1987

Effects of doxazosin and propranolol administration on lipoprotein lipases in cholesterol-fed rats.

The effects of alpha 1-adrenergic receptor inhibition with doxazosin, and beta-blockade with propranolol on tissue lipoprotein lipases and plasma lipids were studied in rats. In rats fed a normal lab chow, doxazosin increased heart lipoprotein lipase activity (+14%), while propranolol had the opposite effect (-20%). These effects were not statistically significant when compared with nontreated controls, although the difference between the doxazosin and propranolol groups was significant (p less than 0.05). There were no significant effects on adipose tissue lipoprotein lipase activity or hepatic lipase activity. In rats fed a cholesterol-enriched diet there were similar but smaller effects on heart lipoprotein lipase activity (+5% and -12%, respectively). In these rats alpha 1-inhibition also tended to increase adipose tissue lipoprotein lipase (+14%) and hepatic lipase (+13%), while beta-blockade had the opposite effect (-20% and -9%, respectively). The lipase activities were significantly different between the treatment groups in liver and heart but not in adipose tissue. Doxazosin and propranolol did not affect plasma triglyceride or total cholesterol, but high-density lipoprotein cholesterol was increased during alpha 1-blockade (+24%).

Adipose Tissue↗