Relationship between diarrhea and intestinal lactase activity

We assessed intestinal structure, mucosal epithelial kinetics, and disaccharidase activities after fasting. Rats fasted for up to 120 hours were compared with control rats fed ad libitum. All rats had free access to water and all were prevented from ingesting their own stools. Body weight, small intestinal weight and mucosal protein, and maltase and sucrase activity of the total small intestine decreased in fasted rats. Lactase activity did not decrease. Specific activity of lactase actually increased in the jejunum. Assessed after a 96-hour fast, jejunal villi were shortened with less epithelial cells along their length and the rate of migration of those cells along the villi was diminished in the fasted rats compared with control rats. We attribute the decreased total intestinal sucrase and maltase activities to a loss of total epithelial cell mass in the small bowel. An abnormality in the cells of the progenitor zone of the crypts is suggested by the decreased migration rate of mucosal epithelial cells in fasting rats. These factors do not explain our observations completely since lactase activity did not diminish. We postulate that the activity of the "acid" β-galactosidase located in the cytoplasm or lysosomes of the epithelial cells was stimulated by fasting. Our observations are relevant to clinical pediatrics. Undernutrition and fasting my be associated with many childhood diseases and with treatment of disease. In assessing clinical data and advising treatment, the pediatrician should be aware of the potentially harmful effects of starvation on intestinal structure and function.

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Relationship between Lactase Activity and Intestinal Flora Structure

Tobacco Regulatory Science ◽

10.18001/trs.7.5.1.81 ◽

2021 ◽

Vol 7 (5) ◽

pp. 3104-3109

Author(s):

Ying Zhang ◽

Mingjian Huang ◽

Jianfeng Chen ◽

Shuyuan Wang ◽

Jian Xu

Keyword(s):

Young Children ◽

Intestinal Tract ◽

Lactose Intolerance ◽

Intestinal Flora ◽

Control Group ◽

Lactase Activity ◽

Beneficial Bacteria ◽

The Relationship ◽

Experimental Group ◽

Infants And Young Children

To analyze and explore the relationship between lactase activity and the structure of intestinal flora in infants under 1 year old. Method: Our hospital selected 60 infants and young children in the Haizhu Maternity and Child Health Hospital from August 2019 to September 2020 as the research objects. The infants in the experimental group were diagnosed as lactose intolerant infants, the control group were normal infants, and the experimental group and control group had 30 cases each. The relationship between lactase activity and intestinal flora structure. Result: The experimental group had fewer beneficial bacteria in the intestinal tract than the control group, but improved lactase activity by correcting the structure of the intestinal flora and alleviating symptoms of lactose intolerance. Conclusion: Infants and young children are prone to non-infectious diarrhea, and the causes are more complicated, but most of them are related to lactose intolerance. When infants and young children develop lactose intolerance, it is necessary to pay attention to the lack of beneficial bacteria in the intestinal tract. Targeted supplementation of probiotics (such as Lactobacillus reuteri, Clostridium butyricum, etc.) can correct the intestinal flora, improve lactase activity, and relieve symptoms of lactose intolerance.

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The Genetic Polymorphism of Adult Intestinal Lactase Activity

Genetics of the Hungarian Population ◽

10.1007/978-3-662-07428-2_9 ◽

1991 ◽

pp. 197-211

Author(s):

G. Flatz

Keyword(s):

Genetic Polymorphism ◽

Lactase Activity

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Relation between dietary-induced increase of intestinal lactase activity and lactose digestion and absorption in adult rats

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1984.247.6.g729 ◽

1984 ◽

Vol 247 (6) ◽

pp. G729-G735

Author(s):

J. Leichter ◽

T. Goda ◽

S. D. Bhandari ◽

S. Bustamante ◽

O. Koldovsky

Keyword(s):

Glucose Absorption ◽

Diet Group ◽

Lactase Activity ◽

Weight Changes ◽

Adult Rats ◽

High Starch ◽

Old Rats ◽

Starch Diet

To study the relation between dietary-induced increase of intestinal lactase activity and lactose absorption, 11-wk-old rats were fed either a high-starch (70 cal%), low-fat (7 cal%) diet or a low-starch (5 cal%), high-fat (73 cal%) diet for 7 days. Food intake and body weight changes were similar in the two dietary groups. In the first experiment, lactose absorption was studied in vivo after oral administration of 600 mg lactose (10% solution in water with added [3H]PEG) to rats fasted for 16 h. Groups of rats were killed at time 0 and at 1-h intervals for the next 3 h. Lactase activity and lactose absorption were significantly higher (P less than 0.01) in the high-starch group than in the low-starch group. In the subsequent experiment, 9-wk-old rats were fed the two isocaloric diets for 3 days. By use of the everted sac technique, we have demonstrated a significantly higher absorption of monosaccharides from lactose in the high-starch diet group; also, glucose transport was higher in the high-starch diet-fed animals. When Tris, an inhibitor of lactase, was added into the mucosal fluid, absorption of lactose was abolished and no effect was seen on glucose absorption (in vivo and in vitro). In both experiments, significant linear regression was established between lactase activity and lactose absorption. Our results thus show that the increase in lactase activity, induced by feeding a high-starch diet to adult rats, is accompanied by an increased capacity to hydrolyze lactose and absorb the constituent monosaccharides.

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New insights into lactase and glycosylceramidase activities of rat lactase-phlorizin hydrolase

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1989.257.4.g616 ◽

1989 ◽

Vol 257 (4) ◽

pp. G616-G623 ◽

Cited By ~ 2

Author(s):

H. A. Buller ◽

A. G. Van Wassenaer ◽

S. Raghavan ◽

R. K. Montgomery ◽

M. A. Sybicki ◽

...

Keyword(s):

Active Sites ◽

Specific Activity ◽

Fold Increase ◽

Developmental Pattern ◽

Lactose Hydrolysis ◽

Adult Males ◽

Lactase Activity ◽

Developmental Patterns ◽

Catalytic Sites ◽

Hydrolysis Of

Lactase-phlorizin hydrolase, a small intestinal disaccharidase, has been considered mainly an enzyme important only for the hydrolysis of lactose. After weaning in most mammals lactase-specific activity falls markedly, and, functionally, adult mammals are considered to be lactase deficient. However, the persistence of low levels of lactase activity in adulthood has never been explained. In addition, it has been suggested that lactase-phlorizin hydrolase is associated with glycosylceramidase activity when the enzyme is prepared by column chromatography, but it is unclear whether this represents copurified activities or two catalytic sites on one peptide. The developmental patterns of lactase-phlorizin hydrolase and other disaccharidases were investigated in homogenates of total rat small intestine; lactase and several glycosylceramidases were measured in immunoprecipitates from these homogenates using a monoclonal antibody. The developmental pattern of total lactase activity showed a steady 2.3-fold increase to adult levels (specific activity decreased eightfold), whereas total phlorizin-hydrolase activity increased 10.7-fold (specific activity decreased threefold). As expected, levels of both total and specific sucrase and maltase activities increased during development. In lactating rats total lactase activity showed a significant increase compared with adult males. The developmental pattern of the enzyme activities for the glycolipid substrates was similar to that found for lactase, and the immunoprecipitated enzyme showed a 40- to 55-fold higher affinity for the glycolipids than for lactose. Galactosyl- and lactosylceramide inhibited lactose hydrolysis by 38%, without a competitive pattern, suggesting two different active sites for lactose and glycolipid hydrolysis, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

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