Bacterial Lipase and High-Fat Diets in Canine Exocrine Pancreatic Insufficiency: A New Therapy of Steatorrhea?

Transcription

1 GASTROENTEROLOGY 1997;112: Bacterial Lipase and High-Fat Diets in Canine Exocrine Pancreatic Insufficiency: A New Therapy of Steatorrhea? AYAKO SUZUKI, AKIYOSHI MIZUMOTO, MICHAEL G. SARR, and EUGENE P. DIMAGNO Gastroenterology Research Unit, Mayo Clinic and Mayo Foundation, Rochester, Minnesota Background & Aims: Nutrients and properties of lipases tions do not abolish steatorrhea in most patients because affect survival of lipolytic activity during aboral gastroin- pellet size and optimum ph of the coatings for enzyme testinal transit. Whether different doses and formula- release preclude adequate mixing of the lipolytic activity tions of bacterial lipase and diets affect steatorrhea with the meal in the upper small intestine. Furthermore, was tested in pancreatic-insufficient dogs. Methods: A daily ingestion of a large number of microencapsulated dose of 0 600,000 IU of powdered and 135,000 and preparations may cause colonic strictures in children with 300,000 IU of liquid bacterial lipase was given with a cystic fibrosis. 12,13 Acid-resistant lipases tested to date, standard meal to 5 dogs with ligated pancreatic ducts. including gastric and fungal lipases, are inactivated by In 4 dogs, 0 or 300,000 IU (normal 6-hour postprandial amount) of powder bacterial lipase was also given with physiological concentrations of bile acids in the lumen five meals containing 850 kcal with different nutrient of the small intestine. 11 caloric densities (mixture design). Coefficients of fat Hence, the ideal lipase should resist acid denaturation absorption during 72-hour fecal balance studies were and proteolytic digestion and maintain lipolytic activity used to assess treatments. Results: With the standard within the milieu of the intestinal tract. We showed meal, powder bacterial lipase reduced steatorrhea in a that the lipolytic activity of bacterial lipase isolated from dose-dependent manner (P Å 0.03), and 135,000 and Burkholderia plantarii, previously called Pseudomonas glu- 300,000 IU of the liquid form decreased steatorrhea mae, 14 survives better in vitro than porcine lipase in humore than powder bacterial lipase (P Å and man gastric or duodenal juice under luminal conditions 0.057, respectively). Coefficients of fat absorption with present postprandially in patients with exocrine pancre- 300,000 IU of powder bacterial lipase correlated (r 2 Å atic insufficiency, 15 maintains activity in the presence of 0.79; P õ 0.001) with increasing proportions of fat calories in diets. Conclusions: Liquid bacterial lipase physiological concentrations of bile acids, and does not decreases steatorrhea more than powder, and require colipase for activity. Thus, we hypothesize that 300,000 IU of powder bacterial lipase ingested with bacterial lipase may be ideal to alleviate pancreatic stehigh-fat meals corrects canine pancreatic steatorrhea. atorrhea. The combination of adequate mixing of small amounts The nutrient composition of meals also may be im- (milligrams) of bacterial lipase and high-fat meals abol- portant in treating pancreatic steatorrhea. Nutrients inishes canine steatorrhea and may abolish human pan- crease the survival of pancreatic enzymes during storcreatic steatorrhea. age, 16 during incubation in human duodenal juice, 17 and during duodenal-ileal transit in normal humans. 18 For teatorrhea caused by chronic pancreatitis rarely is example, incubating lipase at normal postprandial con- Sabolished by commercial preparations of porcine lipancreatic insufficiency (25 IU/mL) with protein and fat, centrations (250 IU/mL) or in concentrations found in pase because the ingested lipase is inactivated within the lumen by acid 1,2 and proteases. 3,4 To date, efforts to cor- but not carbohydrate, prevents loss of lipolytic activity. rect pancreatic steatorrhea have included increasing surthe response to lipase in pancreatic insufficiency. These studies suggest that altering the diet might change vival of lipolytic activity by neutralizing acid with antacids, reducing gastric acid secretion with H 2 blockers 2,5 8 To test our hypotheses, we developed a canine model, or omeprazole 9 or using enteric-coated microsphere forphysiology because canine and human pancreatic and gastrointestinal mulations 2,10 to protect enzymes from denaturation or are similar. 19 Dogs with chronic pancreatic lipases that are resistant to acid denaturation. 11 Although some strategies correct steatorrhea in a minority of paabsorption; Abbreviations used in this paper: CCA, coefficient of carbohydrate CFA, coefficient of fat absorption; CPA, coefficient of tients, they have not gained popularity because they reprotein absorption. quire multiple medications, which reduces compliance 1997 by the American Gastroenterological Association and increases cost. Enteric-coated microsphere formula /97/$3.00

2 June 1997 LIPASE, DIETS, AND STEATORRHEA 2049 insufficiency from ligation of both pancreatic ducts or tween experiments, dogs were fed canned dog food (Hill s after total pancreatectomy survive if carefully managed Prescription Diet, Canine i/d; Hill s Pet Products, Topeka, postoperatively. 20 Our strategy and specific aims were to KS). Each can contained 580 kcal: 48% carbohydrate, 27% determine the dose response to powder bacterial lipase fat, and 25% protein as percentage of calories. Each can of dog food contained 15 g of fat as triglyceride, diglyceride, from B. plantarii while dogs ate standard dog chow and monoglyceride, and fatty acid; 1 g of cholesterol and 1gof then to use the highest dose that did not abolish steatorcholesterol ester; and 0.5 g of phospholipid. Dogs were fed rhea to test the effects of diets and another formulation two cans in the morning and one can in the afternoon. Ten of bacterial lipase (bacterial lipase dissolved in saline and grams of porcine pancreatin powder (Viokase; AH Robins Co., mixed with meals), which might improve the mixing of Richmond, VA) was given with the morning meal, and 7 g the lipolytic activity with the ingested nutrients. We was given with the afternoon meal. also determined if measurements of fecal frequency, consistency, and total or solid stool weights predicted Experimental Design changes in absorption. At the beginning of each experiment, a carmine stool To mimic amounts of lipolytic activity generally used marker (Chemical Mfg. Corp., Gardena, CA) was given with to treat human pancreatic steatorrhea, we gave a low dose a meal. When the carmine appeared in the stools, stools were of 30,000 IU of lipolytic activity, which has a mass of collected for 72 hours. Pancreatic insufficiency experiments 12 mg. This amount of lipolytic activity is contained in began 3 weeks after the operation. eight pancreatin tablets (amounts we have previously For the dose response study, 5 dogs were fed one can of dog tested and used clinically 1,2 ). We also tested 135,000, food with 100 ml of 0.9% NaCl in the morning and afternoon. 300,000, and 600,000 IU of bacterial lipase. We empha- Each meal was given without or with powder bacterial lipase size that giving these higher doses of lipases as pancreatin (30,000, 135,000, 300,000, or 600,000 IU of lipolytic activity [12, 54, 120, or 240 mg]) sprinkled on the surface of the preparations to humans is impossible because the low meal. specific activity of porcine lipase would require ingesting To determine if different formulations of bacterial lipase an exorbitant number (ú35) of tablets. In contrast, adaffected the response in these 5 dogs, we used 135,000 and ministering 300, ,000 IU of bacterial lipase re- 300,000 IU because we found that 600,000 IU of bacterial quires ingesting only mg. lipase corrected steatorrhea in 1 and nearly corrected steatorrhea Materials and Methods in another dog (96% and 89% coefficients of fat absorp- tion [CFA], respectively; see Results). To formulate the liquid Preparation of Pancreatic-Insufficient Dogs lipase, we dissolved the bacterial lipase (water soluble) in the 100 ml of 0.9% NaCl and mixed it with the dog food immediand Their Maintenance ately before the dog ate the meal. Dogs gulped and swallowed All procedures and experiments were reviewed and ap- the meal in õ2 minutes. proved by the Institutional Animal Care and Use Committee To determine the effect of nutrients on steatorrhea, each of 4 of the Mayo Foundation in accordance with the guidelines of dogs (1 of the 5 dogs used in the dose-response and formulation the National Institutes of Health and the Public Health Policy studies was killed during the study because of refusal to eat on the Humane Use and Care of Laboratory Animals. the maintenance diet with the large amount of pancreatin) was We used 5 female dogs weighing between 18 and 21 kg. fed each of the five meals (Figure 1) twice daily for the duration Dogs were anesthetized with intravenous thiopental sodium of each balance study. Two balance studies were performed for (12.5 mg/kg) and maintained with halothane. After a midline each of the test meals. With one balance study, no enzymes celiotomy, all tissue connections between the head of the pan- were given. With the other balance study, 300,000 IU of creas and the duodenum were ligated and transected, including powder bacterial lipase was given with both daily meals. A both the minor and major pancreatic ducts. The inferior and maximum of one balance study was performed on each dog superior pancreatoduodenal vessels were carefully preserved, per week. Between balance studies (a minimum of 4 days, but as were the mesenteric vascular arcades along the duodenum usually ú7 days), dogs were fed the maintenance diet with proximal and distal to the region of the duodenum adjacent pancreatin, as previously described. Administration of the test to the head of the pancreas. Transection and ligation of all meals and bacterial lipase was in random order. pancreaticoduodenal connections is important. In several dogs, The five meals consisted of 850 kcal that had the proportions individual ligation and transection of just the major and minor of nutrients distributed according to a mixture design. 21 The ducts failed to completely abolish intraluminal protease and nutrient composition of the meals was adjusted by adding to one lipase activity. These dogs did not have malabsorption and can of dog food varied quantities of Promod (protein supplement were not used for this study. made from whey; Ross Laboratories, Columbus, OH), Polycose After surgery, the dogs were housed in individual cages. (glucose polymers of approximately 1000 daltons in powder The absence of intraduodenal protease and lipase activity was form; Ross Laboratories), and corn oil. Meals (numbered in order confirmed in each dog before the study. For maintenance be- of percentage of calories as fat in the meals) were low fat, low

3 2050 SUZUKI ET AL. GASTROENTEROLOGY Vol. 112, No. 6 pearled barley, and soybean meal. In particular, the types of fat were similar among the test meals (Kathy L. Gross, Ph.D., personal communication, September 1994) (Table 1). In addition, the five meals had similar energy content because digestibility (proportion of nutrients available for absorption by the dog) of protein, fat, and carbohydrate in canned foods was similar among test meals, i.e., 84.5% 93.5%, 95.5% 97.2%, and 88.6% 91.2%, respectively (Marilyn Colgon, D.V.M., personal communication, August 1994). Each of the meals had a low fiber content ( g/ d). Lastly, because the physical properties among test meals could affect fat absorption, we standardized the total volume and ph among the meals and the osmolality in four of the five meals (Table 1). The bacterial lipase used in these studies (Knoll AG, Ludwigshafen, Germany) has a molecular weight of 30,000, is Figure 1. (A) Triangular diagram and (B) table of the distribution of acid-stable, contains 319 amino acids, and is secreted by B. percentage of calories of fat, protein, and carbohydrate in diets. The plantarii during fermentation. In contrast to porcine lipase, horizontal axis is protein from 0% (left) to 100% (right), the right axis this lipase does not require colipase for activity. There are at is fat from 0% (bottom) to 100% (top), and the left axis is carbohydrate least two forms of the enzyme containing two or four molecules from 0% (top) to 100% (bottom). per asymmetric unit. 14 The specific activity of the preparation is 3,000 IU lipolytic activity per milligram. protein, and high carbohydrate (meal 1); low fat, high protein, Analyses and high carbohydrate (meal 2); relatively even distribution of The 72-hour stool collections were weighed, and the rethree nutritional classes (meal 3); high fat, high protein, and sults are expressed as grams per 24 hours. Fecal fat, 22 nitrogen, 23 low carbohydrate (meal 4); and high fat, low protein, and high and carbohydrate 24 were measured and the results expressed as carbohydrate (meal 5). The percentage of calories of fat, protein, CFA, coefficient of protein (CPA; nitrogen converted to protein and carbohydrate in the meals was selected on the basis of an by assuming that protein contained 16% nitrogen) or coefficient ethical constraint area (daily requirements of each of the nutriof carbohydrate absorption (CCA). Fecal consistency was scored ents) and by determining what the dogs would eat (palatability) as grade 1 (normal-looking and formed), grade 2 (mushy), or (Figure 1). The mineral content of the five meals was adjusted grade 3 (liquid). Fecal frequency, the fecal score (product of consisby adding calcium citrate, sodium citrate, potassium citrate, tency and frequency), and total and solid stool weights are resodium phosphate, potassium chloride, and magnesium oxide ported per 24 hours. so that the mineral requirement per day was exceeded but nearly equal among the meals (Table 1). The ingredients were similar Data and Statistical Analysis among meals and consisted of chicken, turkey, beef lung, whole Results are expressed as mean values { SE of the coefficients of absorption. To avoid unequal variances of a egg, ground corn, liver, animal fat (chicken, pork), rice, cracked propor- Table 1. Meal Composition Meal 1 Meal 2 Meal 3 Meal 4 Meal 5 Volume (ml) ph Osmolality (mosm ) Ca 2/ Na / K / Cl P Mg Fat composition Short chain Median chain Long chain Saturated Unsaturated Saturated/unsaturated NOTE. Total volume, ph, and osmolality are values obtained after blending a meal with 100 ml saline. The mineral content (Ca 2/,Na /,K /, Cl 0, P, and Mg) is expressed as milligrams per day (two meals). Fat composition is the percent distribution of fatty acids in the meal.

4 June 1997 LIPASE, DIETS, AND STEATORRHEA 2051 tion or a percentage at their extremes, 25 we transformed the proportions to arcsines 25 or used fecal fat (grams per 24 hours) to perform statistical analyses. Data were assessed by analysis of variance for repeated measures. In certain analyses, repeated t tests were performed to determine if there were significant differences among treatments; the Bonferroni correction was used whenever appropriate. To analyze differences among meals, we performed analysis of variance for repeated measures with the Tukey correction. Multiple regression analyses were performed to detect relationships among fecal data and nutrients. Results Figure 3. Fecal fat in response to no treatment ( ) or 300,000 IU Effects of Exocrine Pancreatic powder bacterial lipase ( ) in 4 dogs with different diets (horizontal Insufficiency on Body Weight, Appetite, axis, ascending order of percentage of fat calories in meals). Values are mean { SE. *P õ vs. meal 1, 2, and 3. and Blood Glucose Dogs with pancreatic insufficiency lost 7% { 2% (2% 13%) of their body weight but had good appetites highest CFA with 300,000 IU was 77%. In pancreaticand appeared otherwise healthy; postprandial blood glucose insufficient dogs, the CPA was significantly lower than concentrations of õ100 mg/dl were not different from in normal dogs (39% { 3% vs. 75% { 5%; P Å 0.001) normal throughout the experiments (data not shown). and was not altered by bacterial lipase. Effect of Liquid Lipase Dose Response of Powder Bacterial Lipase Giving 135,000 and 300,000 IU of liquid lipase increased the CFA more than the same doses of powder In dogs with pancreatic insufficiency without lipase (P Å and 0.057, respectively; Figure 2B); treatment, the CFA was less than preoperative values however, these doses of liquid lipase did not increase (63% { 6% vs. 96% { 1%; P õ 0.01). Bacterial lipase CFA ú600,000 IU of powder lipase (Figure 2B). increased the CFA in a dose-dependent manner (P Å 0.03). Giving 600,000 IU of bacterial lipase decreased Effect of 300,000 IU of Powder Bacterial steatorrhea ú30,000 IU (P õ 0.05; Figure 2A). With Lipase With Different Diets 600,000 IU, 1 dog corrected (96% CFA) and 1 nearly Fecal fat and fat absorption. Without bacterial corrected (89% CFA) steatorrhea. By comparison, the lipase, fecal fat (grams per 24 hours; Figure 3) and CFA (Figure 4) differed among meals (P õ and P õ Figure 2. Effects of powder and liquid bacterial lipase in 5 pancreaticinsufficien dogs with a diet of 47% carbohydrate, 30% fat, and 23% protein. KU Å 10 3 U. (A) Dose response (mean { SE) to powder Figure 4. Effects of bacterial lipase on coefficien of fat absorption bacterial lipase ( ) and response to liquid lipase ( ). *P õ with different diets in each of 4 dogs. (A) Response to no treatment (B) Response to liquid and powder lipase at 135,000 ( and solid ( ) or 300,000 IU powder bacterial lipase ( ) with different diets lines) and 300,000 ( and dotted lines) IU. Note the different vertical (horizontal axis, ascending order of percentage of fat calories in scales for A and B: (A) 0% 100%; (B) 40% 100%. **P Å meals). Values are mean { SE. *P õ (B) Each combination of (powder vs. liquid 135,000 IU bacterial lipase) and P Å (powder symbol and line is 1 of 4 dogs. r Å for the 4 dogs (P vs. liquid 300,000 IU bacterial lipase). Å for slopes vs. 0).

5 2052 SUZUKI ET AL. GASTROENTEROLOGY Vol. 112, No. 6 out or with bacterial lipase (r 2 Å 0.72, P õ and r 2 Å 0.95, P õ 0.001, respectively). CCA. CCA differed among meals without and with bacterial lipase (P õ 0.04; P õ 0.001), and within a meal, CCA was similar regardless of treatment except for meal 4 (high fat, high protein, low carbohydrate). With meal 4, bacterial lipase increased CCA (P Å 0.05; first pair of columns in Figure 6), which was greater than meals 2 and 1 (P õ 0.02; second and fifth columns in Figure 6). Without and with bacterial lipase, there was a trend toward an inverse correlation between CCA and the percentage of carbohydrate calories in meals (r 2 Å 0.428, P Å and r 2 Å 0.419, P Å 0.07, respectively), and a significant direct correlation between the Figure 5. CPA in response to no treatment ( ) and 300,000 IU powder bacterial lipase ( ) with different diets (horizontal axis arranged amount of absorbed carbohydrate and the amount of carin ascending order of percentage of protein calories in meals). Values bohydrate in the meal (r 2 Å 0.98, P õ and r 2 Å are mean { SE. *P õ , P õ 0.001, respectively). Fecal frequency, consistency, and score. In pancreatic-insufficient dogs, fecal scores (Table 2) gener , respectively). Fecal fat was significantly greater ally paralleled fecal frequencies and consistencies (data with the two high-fat meals (meals 4 and 5; P õ ). not shown) and were significantly greater than preopera- The CFA of meal 3 (relatively even distribution of three tive values of the dogs when they were fed the maintenutritional classes) was greater (P õ 0.01) than that of nance diet (1.9 { 0.4; P õ 0.02). Fecal scores were also meals 1 (low fat, low protein, high carbohydrate) and 4 different among meals (Table 2; P õ 0.05), directly (high fat, high protein, low carbohydrate), and the CFA correlated with the percentage of protein calories in the of meal 2 was greater than that of meal 1 (P Å 0.04). meal (r 2 Å 0.649, P õ and r 2 Å 0.597, P õ In contrast, with powder bacterial lipase, fecal fat was 0.01, without and with bacterial lipase, respectively), approximately 10 g/24 h among all meals (Figure 3). and inversely correlated with the combined percentage Bacterial lipase reduced fecal fat with meals 1, 4, and 5 of fat and carbohydrate calories in the meal (r 2 Å 0.658, (P õ 0.01), but not with meals 2 or 3 (Figure 3). The P õ 0.01 and r 2 Å 0.678, P õ 0.01, without and with amount of absorbed fat correlated with the amount of bacterial lipase, respectively). Without bacterial lipase, fat in the meals (r 2 Å 0.99; P õ 0.001; data not shown). the fecal score of meal 2 (highest protein content) was CFA in response to powder bacterial lipase (Figure greater than all other meals (P õ 0.002), and the fecal 4A) differed among meals (P õ ) and correlated with increasing percentage of fat calories in the meals (r 2 Å 0.79; P õ 0.001). Bacterial lipase increased the CFA of meals 1, 4, and 5 (P õ 0.01), but not of meals 2 or 3 (Figure 4). Within each dog (Figure 4B), CFA directly correlated (r Å ; slopes vs. 0, P Å 0.002) with the percentage of fat calories in the diet. CPA. CPA differed among meals regardless of treatment without or with bacterial lipase (P õ 0.03 and 0.01, respectively), but bacterial lipase did not affect CPA within each meal. Without bacterial lipase, CPA was lowest with meal 5 (high fat, low protein, high carbohydrate; first column in Figure 5), which was less (P õ 0.05) than meals 2, 3, and 4 (pairs of columns 3, 4, and 5 in Figure 5). CPA directly correlated with percentage of protein calories in meals without or with bacterial lipase (r 2 Å 0.46, P õ 0.05 and r 2 Å 0.78, P Figure 6. CCA in response to no treatment ( ) and 300,000 IU pow- õ 0.001, respectively). The amount of absorbed protein also correlated with the amount of protein in meals with- der bacterial lipase ( ) in 4 dogs with different diets (horizontal axis, ascending order of percentage of carbohydrate calories in meals). Values are mean { SE. *P õ 0.02.

6 June 1997 LIPASE, DIETS, AND STEATORRHEA 2053 Table 2. Fecal Score, Total Stool Weight, and Solid Weight in Stool According to Percentage of Fat, Carbohydrate, and Protein as Caloric Value in Five Meals Fecal score a Total stool weight (g) b Solid weight in stool (g) c F C P Meal (%) (%) (%) No treatment BL 300,000 IU No treatment BL 300,000 IU No treatment BL 300,000 IU { 0.4 d 6.1 { { { { { { 0.3 e 11.6 { { { { { { { { { { { { { { 41 g,h 430 { { 14 g 131 { { { 1.4 f 534 { 49 h 377 { { 14 h 92 { 14 i BL; bacterial lipase. a P õ 0.05 among meals with no treatment; P õ 0.02 among meals with BL 300,000 IU. b P õ 0.05 among meals with no treatment. c P õ 0.05 among meals with no treatment and BL 300,000 IU. d P õ 0.01 vs. meals 3 and 4. e P õ vs. all other meals. f P õ 0.03 vs. meal 2. g P õ 0.05 vs. meal 3. h P õ 0.03 vs. BL 300,000 IU. i P õ 0.05 vs. meal 2. Treatment of human pancreatic steatorrhea is not optimal and rarely abolishes the condition. In contrast, we show that 300,000 IU (120 mg) of bacterial lipase corrects steatorrhea in canine exocrine insufficiency when ingested with meals containing a high proportion of fat as calories. This amount of lipolytic activity is secreted normally 4 6 hours postprandially (300,000 IU) in hu- mans 26 and dogs. 27 Thus, human pancreatic steatorrhea might be abolished by giving milligrams of bacterial lipase containing large amounts of lipolytic activity with high-fat meals. This treatment is a drastic departure from current treatment of human exocrine insufficiency and is im- portant to consider in planning clinical trials. In patients with severe exocrine pancreatic insufficiency, 30,000 IU score of meal 1 (high carbohydrate, low fat, low protein) was lower than meals 3 and 4 (P õ 0.01). With bacterial lipase, the fecal score of meal 2 was also higher than the other meals and significantly higher than meal 5 (high carbohydrate, high fat, low protein; P õ 0.03), the meal with the lowest fecal score. Weights of the total and solid components of stool. In pancreatic-insufficient dogs in the absence of bacterial lipase, the total and solid stool weights differed among meals (P õ 0.05 and P õ 0.04, respectively); stool weights of meal 3 (relatively even distribution of three nutritional classes) were the lowest, significantly lower than meal 4 (P õ 0.05; low carbohydrate, high fat, high protein). Bacterial lipase decreased (P õ 0.03) total stool weights of both high fat meals (meals 4 and 5) and the solid fecal weight of meal 5. With bacterial lipase, the solid fecal weight of meal 5 was the lowest, significantly lower than that of meal 2 (P õ 0.05; high carbohydrate, low fat, high protein), which had the highest fecal solid weight with treatment. Without and with bacterial lipase, total (Figure 7) and solid (data not shown) stool weights inversely correlated with CFA. With bacterial lipase, total and solid stool weights also inversely correlated with CCA (r 2 Å 0.511, P õ 0.05 and r 2 Å 0.475, P õ 0.04, respectively). Without treatment, stool weights did not correlate with meal nutrients; however, with bacterial lipase, total and solid stool weights correlated inversely with the percentage of fat calories (r 2 Å 0.696, P õ and r 2 Å 0.649, P Å 0.002, respectively) and directly correlated with the total percentage of protein and carbohydrate calories (r 2 Å 0.697, P õ and r 2 Å 0.759, P Å 0.001, respectively) in meals. Discussion Figure 7. Relation between total stool weight and CFA with different diets in 4 dogs; (A) no treatment, (B) 300,000 IU bacterial lipase (BL). Each combination of symbol and line is 1 of 4 dogs. (A) r Å for the 4 dogs (P Å for slopes vs. 0); (B) r Å for the 4 dogs (P Å for slopes vs. 0). Note the different horizontal scales for A (20% 80%) and B (60% 95%).

7 2054 SUZUKI ET AL. GASTROENTEROLOGY Vol. 112, No. 6 of porcine lipase reduces steatorrhea by ú50% but does lipoprotein a. 31 What produces these abnormalities is not abolish steatorrhea; most patients continue to excrete unknown, but malabsorption, malnutrition, and meta g of fat per 24 hours. 1,2 In these studies, pa- bolic abnormalities associated with smoking and drinking tients were fed high-fat diets with 100 g of fat in equally may be involved. divided amounts of 25 g of fat in four meals daily. Under In general, fecal characteristics (fecal score) correlated these conditions, abolishing steatorrhea requires gastric directly with the proportion of protein in diets regardless acid neutralization, antisecretory agents, or microencap- of treatment, but treatment with bacterial lipase and a sulation with enteric coatings; however, even these adju- high proportion of fat in the diet was associated with vants do not abolish steatorrhea in all patients. the lowest fecal score and lowest total and solid fecal In untreated canine pancreatic insufficiency, fecal fat weights. We interpret these data to suggest that meals markedly increased when the caloric proportion of fat in with a high proportion of protein might increase symp- meals was ú40%; CFA was greatest with meal 3 (relais toms because of malabsorption, and if fat malabsorption tively equal proportions of nutrients as calories). In subtion corrected but protein (and/or carbohydrate) malabsorp- jects with untreated pancreatic insufficiency, this meal is not, symptoms of malabsorption will continue. had a similar CFA as meal 1 (lowest fat, low protein, However, amelioration of steatorrhea by bacterial lipase and the highest carbohydrate) with bacterial lipase. In should reduce symptoms, because total stool weight and contrast, with bacterial lipase, fecal fat was approximately solid weight were inversely correlated with CFA and 10 g/day among all meals. As we increased the amount CCA, but not CPA. Furthermore, stool weight is likely of fat in meals, more fat was absorbed, resulting in higher a better predictor of the response to treatment of malab- CFA. We interpret these data as indicating that to insure sorption (other than measurement of nutrients in stool) optimal nutrition in subjects with untreated pancreatic than fecal score or frequency. insufficiency, meals should have balanced caloric proportreatment We suggest that in human exocrine insufficiency, tions of the nutrients; however, if exogenous lipase is with lipase and a high proportion of fat in the administered, a high-fat diet may improve fat malabsorpabolition diet will reduce fecal frequency and amount of stool, but tion. This is an iconoclastic opinion; generally, patients of symptoms requires abolition of malabsorp- with pancreatic insufficiency restrict intake of fats to tion of other nutrients, particularly protein. To comrelieve symptoms of malabsorption. pletely correct malabsorption requires the use of proteo- We have under investigation several possibilities of lytic enzymes, amylase, and lipase. Further investigations why fat absorption varies in response to bacterial lipase are needed to conclude which diets best alleviate stool with meals of different nutrient composition: (1) differ- symptoms in pancreatic insufficiency. ences in the survival of lipolytic activity induced by nusignificance. In summary, our findings may have direct clinical trients; (2) alterations of gastrointestinal transit (mixing A stable lipase that efficiently digests fat and coordination between lipase and lipid delivery); (3) intraluminally would greatly simplify treatment of pandifferences in duodenal ph and bile acid/micelle concenneutralizing, creatic steatorrhea by eliminating the need for using acid- trations; (4) interaction of fat with other undigested nutrients antisecretory drugs, or enteric coatings. in the intestinal lumen; and (5) changes in the Bacterial lipase may fulfill these requirements. In addi- rate of fatty acid absorption by intestinal cells. However, tion, our study supports ingesting high-caloric, high-fat we conclude that the present study shows that in pancreespecially meals in exocrine pancreatic insufficiency, which would atic insufficiency, fat absorption is directly dependent on benefit children with cystic fibrosis who need the load of fat in diets when a normal amount of lipase better nutritional management to enhance growth and (in this study as bacterial lipase) is given with meals. development, and should reduce morbidity and mortality It is important to abolish steatorrhea. In children with in patients with cystic fibrosis or chronic pancreatitis. cystic fibrosis, correction of malabsorption may decrease morbidity and increase survival, because correcting malabsorption References may restore normal growth and slow the de- 1. DiMagno EP, Malagelada J-R, Go VLW, Moertel CG. Fate of orally cline of pulmonary function. 28 Adults with exocrine pandosage ingested enzymes in pancreatic insufficiency comparison of two schedules. N Engl J Med 1977; 296: creatic insufficiency have a significantly shortened life 2. Regan PT, Malagelada J-R, DiMagno EP, Glanzman SL, Go VLW. span, 29 partly because of an increase in atheromatous Comparative effects of antacids, cimetidine, and enteric coating large vessel disease and resultant cardiovascular disease. 30 on the therapeutic response to oral enzymes in severe pancreatic insufficiency N Engl J Med 1977; 297: Patients with chronic pancreatitis have lower plasma lev- 3. Thiruvengadam R, DiMagno EP. Inactivation of human lipase by els of factors that may protect against atherogenesis, in- proteases. Am J Physiol 1988; 255:G476 G481. cluding high density lipoprotein-c, apoprotein a1, and 4. Thiruvengadam R, Zinsmeister AR, DiMagno EP. Is human lipase

8 June 1997 LIPASE, DIETS, AND STEATORRHEA 2055 survival during aboral intestinal transit dependent upon intralumi- trypsin (CT) or bile acid (BA) entering the duodenum (abstr)? nal chymotrypsin (CT) activity and bile acid concentrations (BAC)? Gastroenterology 1991;100:A276. Dig Dis Sci 1987; 32: DiMagno EP, Layer P. Human exocrine pancreatic enzyme secretion. 5. Graham DY. Pancreatic enzyme replacement: the effect of antacids In: Go VLW, DiMagno EP, Gardner JD, Lebenthal E, Reber or cimetidine. Dig Dis Sci 1982; 27: HA, Scheele GA, eds. The pancreas: biology, pathobiology and 6. Saunders JH, Drummond S, Wormsley KG. Inhibition of gastric diseases. New York: Raven, 1993: secretion in treatment of pancreatic insufficiency Br Med J 1977; 20. Malfertheiner P, Sarr MG, DiMagno EP. Role of the pancreas in 1: the control of interdigestive gastrointestinal motility. Gastroenter- 7. Regan PT, Malagelada J-R, DiMagno EP, Go VLW. Rational for ology 1989; 96: use of cimetidine in pancreatic insufficiency Mayo Clin Proc 21. Cornell JA. Experiments with mixtures. New York: Wiley, ; 53: van de Kamer JH, Huinink HTB, Weyers HA. Rapid method for 8. Zentler-Munro PL, Fine DR, Batten JC, Northfiel TC. Effect of the determination of fat in feces. J Biol Chem 1949; 177:347 cimetidine on enzyme inactivation, bile acid precipitation, and 355. liquid solubilisation, in pancreatic steatorrhea due to cystic fi 23. Chibnall AC, Rees MW, Williams EF. The total nitrogen content brosis. Gut 1985; 26: of egg albumin and other proteins. Biochem J 1943; 37: Heijerman HG, Lamers CB, Bakker W. Omeprazole enhances the 359. efficac of pancreatin (pancrease) in cystic fibrosis Ann Intern 24. Layer P, Zinsmeister AR, DiMagno EP. Effects of decreasing intra- Med 1991; 114: luminal amylase activity on starch digestion and postprandial 10. Dutta SK, Rubin J, Harvey J. Comparative evaluation of the thera- gastrointestinal function in humans. Gastroenterology 1986; 91: peutic efficac of a ph sensitive enteric coated pancreatic en zyme preparation with conventional pancreatic enzyme therapy 25. Fleiss JL. The design and analysis of clinical experiments. New in the treatment of exocrine pancreatic insufficiency Gastroenter- York: Wiley, 1986: ology 1983; 84: DiMagno EP, Go VLW, Summerskill WHJ. Impaired CCK-PZ secre- tion, intraluminal dilution and maldigestion of fat in sprue. Gas- 11. Zentler-Munro PL, Assouf BA, Balasubramanian K, Cornell S, troenterology 1972; 63: Benoliel D, Northfiel TC, Hodson ME. Therapeutic potential and 27. Koike D, Yamdera K, DiMagno EP. Effect of a wheat amylase clinical efficac of acid-resistant fungal lipase in the treatment inhibitor on canine carbohydrate digestion, gastrointestinal funcof pancreatic steatorrhea due to cystic fibrosis Pancreas 1992; tion and pancreatic growth. Gastroenterology 1995; 108:1221 7: Smyth RL, van Velzen D, Smyth AR, Lloyd DA, Heaf DP. Strictures 28. Gaskin K, Gurwitz D, Durie P, Corey M, Levinson H, Forstner G. of ascending colon in cystic fibrosi and high-strength pancreatic Improved respiratory prognosis in cystic fibrosi patients with enzymes. Lancet 1994; 343: normal fat absorption. J Pediatr 1982; 100: Taylor CJ. Colonic strictures in cystic fibrosis Lancet 1994; 343: 29. Layer P, Yamamoto H, Kalthoff L, Clain JE, Bakken LJ, DiMagno EP. The different courses of early and late onset idiopathic and 14. Cleasby A, Garman E, Egmond MR, Batenburg M. Crystallization alcoholic chronic pancreatitis. Gastroenterology 1994; 107: and preliminary x-ray study of a lipase from Pseudomonas glu mae. J Mol Biol 1992; 224: Gullo L, Stella A, Labriola E, Costa PL, Descovich G, Labo G. 15. Raimondo M, DiMagno EP. Lipolytic activity of bacterial lipase Cardiovascular lesions in chronic pancreatitis. A prospective survives better than that of porcine lipase in human gastric and study. Dig Dis Sci 1982; 27: duodenal content. Gastroenterology 1994; 107: Montalto G, Soresi M, Carroccio A, Scafid E, Barbagallo CM, 16. Kelly DG, Sternby B, DiMagno EP. How to protect human pancre- Ippolito S, Notarbartolo A. Lipoproteins and chronic pancreatitis. atic enzyme activities in frozen duodenal juice. Gastroenterology Pancreas 1994; 9: ; 100: Kelly DG, Sandberg RJ, Bentley KJ, Zinsmeister AR, DiMagno Received November 18, Accepted March 3, EP. Protection of lipolytic activity (L) by nutrients in simulated Address requests for reprints to: Eugene P. DiMagno, M.D., Gastropancreatic insufficienc (abstr). Pancreas 1988; 3:601. enterology Research Unit (AL 2-435), Mayo Clinic, 200 First Street 18. Holtmann G, Kelly DG, Sandberg RJ, Bentley KJ, Magocsi L, Di- Southwest, Rochester, Minnesota Fax: (507) Magno EP. Is the survival of human lipolytic activity (LA) during Supported in part by a grant from Knoll AG, Ludwigshafen, Geraboral transit affected by the amount of calories, nutrient, chymo- many.