Relationship between Lactase Activity and Intestinal Flora Structure

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.

Activity Of Enteral Lactase And Lactobacilli In Maternal And Hereditary Toxic Anemia

In this paper, the activity of lactobacilli in the small intestine and lactobacilli in the colon, which are involved in the digestion of milk sugar during lactotrophy using phenylhydrazine hydrochloride, studied the effects of toxic anemia on mother and child. Erythrocyte counts, hemoglobin levels, lactase enzyme activity in the small intestine, and lactobacilli activity in the colon were determined in 12- and 24-day-old rats born to mother anemic rats with toxic anemia under the influence of phenylhydrazine hydrochloride, and in growing rats after mother and offspring toxic anemia. Experiments in white rats have shown that in rats growing in experimental toxic anemia of mother and offspring, there is an increase in lactase activity in the small intestine and a decrease in lactobacilli activity depending on the degree of intoxication in the colon.

Cow's milk consumption and risk of disease

Milk and dairy products are important components of the human diet. This has been true since the beginning of domestication of lactating animals. However, milk of any species is geared towards the growth and development of its own offspring. Thus, the role of milk and dairy products in human nutrition has been increasingly discussed in recent years. To the best of our knowledge, problems such as lactose intolerance, protein allergies and an increased risk of cancer can occur when consuming cow’s milk. Around 70% of the world's total population is lactose intolerant, while 20% of adults in Europe are lactose intolerant. In the small intestine, lactose is hydrolytically split into glucose and galactose by the enzyme lactase located in the mucous membrane cells. After infancy, lactase activity decreases as the ability to synthesize lactase is lost. As a result, adults can no longer tolerate large amounts of lactose, and many develop diarrhea and uncomfortable painful symptoms such as gas, cramps, and a bloated stomach. Since lactase activity is limited in the case of hereditary lactose intolerance, people can easily tolerate milk without lactose. Another aspect is that between 2-5% of children are allergic to cow's milk. The allergy is less common in adulthood. Most allergic reactions affect the skin, gastrointestinal tract, and respiratory system, and severe anaphylaxis can occur. A therapeutic approach related to the causes of this multi-organ disease does not yet exist. A possible approach to reducing protein allergens is to block IgE-binding epitopes in patients. The most effective treatment is an elimination diet and the use of appropriate substitution formulas. Camel milk may replace cow's milk in the event of intolerance. Furthermore, many studies have showed that people with a higher cow’s milk intake had slightly increased cancer and all-cause mortality rates. In conclusion, it has not been clarified what exactly constitutes the harmful or health-promoting effects of cow's milk. Cow's milk is so rich in ingredients that both effects are conceivable. Due to the central importance of milk and dairy products for human nutrition, there is still great scientific interest in expanding knowledge concerning the ingredients and their nutritional and physiological effects.

A retrospective study on the association of gastrointestinal symptoms in children with low lactase activity and low activity of other disaccharidases

Background Disaccharides such as lactose and sucrose are sugars commonly found in human diet. They are broken down by mucosal disaccharidases in the duodenum. Previous small studies found no associations between gastrointestinal (GI) symptoms and combined low disaccharidase activity. We aim to explore the associations of low activity of disaccharidase and combinations of low activity of different disaccharidases with general GI symptom presentations in a large cohort of pediatric patients. Methods We examined a cohort (0–21 yrs.) who have undergone esophagogastroduodenoscopy and received disaccharidase activity assay from duodenal biopsy in the time period 2010 to 2012. Disaccharidase assays tested for activity of lactase, sucrase, maltase, and palatinase. GI symptoms were grouped into four categories, abdominal pain, diarrhea, weight loss, and gastroesophageal reflux. Results Of the 347 subjects, we found an association between low lactase activity and abdominal pain (OR = 1.78; 95% CI = 1.07–2.97; p < 0.05). Subjects with a lactase/sucrase ratio < 0.2 were found to be associated with abdominal pain (OR = 2.25; 95% CI = 1.25–4.04; p < 0.05), Subjects with low pandisaccharidase may be correlated with abdominal pain and have a unique frequency of GI symptoms due to low frequency of diarrhea and weight loss, but they were not statistically significant. Conclusions Low activities of certain disaccharidase combinations may be associated with GI symptoms in subjects; a prospective study may be needed to investigate further.

Disaccharidase deficiency

Disaccharidases are abundant enzymes expressed on the microvillous membrane of the small intestine: apart from free glucose and fructose, disaccharidases are required for the complete assimilation of nearly all carbohydrate present in food and drinks. The enzymes cleave disaccharides such as sucrose, maltose, and lactose, as well as dextrins derived from starch, into their component monosaccharides. Their activity is reduced in hereditary conditions or in generalized intestinal diseases. Disaccharidase deficiency causes dietary intolerance of carbohydrate induced by the fermentation of undigested sugars in the distal small intestine and colon. Abdominal symptoms are usually noticed within an hour of the ingestion of foods containing the offending sugars. By far the most common symptomatic disaccharidase deficiency is lactose intolerance. Lactase activity is high in healthy infants when milk is the principal food, but in most humans the activity declines after weaning and remains low (lactase nonpersistence), which greatly reduces the capacity to break down lactose. In contrast, those inheriting a Mendelian dominant trait that leads to sustained high intestinal lactase expression throughout life (lactase persistence) digest and tolerate large quantities. The distribution of lactase activity in adult populations is subject to great variation. Intestinal lactase phenotypes can be identified by assay of mucosal biopsy samples or appropriate sugar tolerance tests, as can other (much rarer) genetically determined disaccharidase variants. The most convenient diagnostic screen involves hydrogen breath testing after oral loading. Disaccharide intolerance is readily treated by institution of a strict exclusion diet; oral enzymatic supplementation may benefit patients with severe enzymatic deficiency. Innovative and early phase clinical trials suggest that modulation of the host intestinal microbiome with a pure short-chain galacto-oligosaccharide may be beneficial in symptom control and in favouring the outgrowth of lactose-fermenting flora.

PSIV-1 Effects of nutrient restriction and realimentation of gestating ewes on fetal carbohydrase activities in the small intestine

The small intestine plays an important role in post-ruminal carbohydrate digestion and there is limited information on its function in response to nutritional adaptation. To examine the effects of nutrient restriction and realimentation on fetal small intestinal carbohydrase activities during mid- to late-gestation, 41 singleton ewes (48.3±0.6 kg BW) were randomly assigned to dietary treatments: 100% (control; CON; n = 20) or 60% of nutrient requirements (restricted; RES; n = 21) from day 50–90 (mid-gestation) of gestation. At day 90, 14 ewes (CON, n = 7; RES, n = 7) were slaughtered. The remaining ewes were subjected to treatments of nutrient restriction or remained under a control diet from day 90–130 (late-gestation): CON-CON (n = 6), CON-RES (n = 7), RES-CON (n = 7), and RES-RES (n = 7) and were slaughtered at day 130. The fetal small intestine was weighed, subsampled, and assayed for carbohydrase (maltase, isomaltase, glucoamylase, lactase, and sucrase) activity. Enzyme activity was expressed as U/g and U/g protein. Protein concentration was expressed as mg/g intestine. Differences between means were determined using contrasts in the MIXED procedure of SAS. Small intestinal mass increased (P &lt; 0.001) with day of gestation. Sucrase activity was undetected in the small intestine. Day of gestation did not affect carbohydrase development in the fetal small intestine. Nutrient restriction did not affect glucoamylase, maltase, or isomaltase activities. There was a significant mid-gestation treatment × late-gestation treatment interaction for lactase activity (P &lt; 0.05). Realimentation during late-gestation after nutrient restriction during mid-gestation increased lactase activity in the fetal small intestine. These data demonstrate that fetal mucosal carbohydrases are imprinted early in gestation and brush border α-glycohydrolases involved in starch digestion (maltase, isomaltase, glucoamylase) do not respond to maternal nutrient restriction in sheep. Nutrient restriction of ewes during mid-gestation followed by realimentation during late-gestation may be a programming strategy to increase fetal lactase activity.

Polymorphism of C/T-13910 lactase gene and anthropometric data of girls born in Samara

Objectives -to assess the prevalence of C/T-13910 polymorphism of the lactase gene in the population of children in Samara and to identify the relationship with height, body weight and body mass index. Material and methods. The study included 103 girls aged 3-6 years. Their height and body weight were measured, and buccal samples were taken to genotype lactase activity (determining the C/T-13910 variant). Results. In girls born and living in Samara, the frequency of allele 13910-T was 48.6%. The СС genotype was detected in 51.4%, the СГ genotype in 37.9% and the TT genotype in 10.7%. There was no statistically significant relationship between genotype and body weight and height, but all children with the TT genotype had a height of more than 25 percentiles, the vast majority of overweight and obese girls (91%) had the СС genotype or the CT genotype.