Invertase, maltase, lactase, and peroxidase activities in duodenum of BB rats

The combination of metagenome and metabolome to compare the differential effects and mechanisms of fructose and sucrose on the metabolic disorders and gut microbiota in vitro and in vivo

Sucrose and fructose are the most commonly used sweeteners in the modern food industry, but there are few comparative studies on the mechanisms by which fructose and sucrose affect host health. The aim of the present study was to explain the different effects of fructose and sucrose on host metabolism from the perspective of gut microbiota. Mice were fed for 16 weeks with normal drinking water (CON), 30% fructose drinking water (CF) and 30% sucrose drinking water (SUC). Compared with fructose treatment, sucrose caused significantly higher weight gain, epididymal fat deposition, hepatic steatosis, and jejunum histological injury. Sucrose increased the abundance of LPS-producing bacteria which was positively correlated with obesity traits, while fructose increased the abundance of Lactobacillus. An in vitro fermentation experiment also showed that fructose increased the abundance of Lactobacillus, while sucrose increased the abundance of Klebsiella and Escherichia. In addition, combined with microbial functional analysis and metabolomics data, fructose led to the enhancement of carbohydrate metabolism and TCA cycle capacity, and increased the production of glutamate. The cross-cooperation network greatly influenced the microbiota (Klebsiella, Lactobacillus), metabolites (glutamate, fructose 1,6-biosphosphate, citric acid), and genes encoding enzymes (pyruvate kinase, 6-phosphofructokinase 1, fructokinase, lactate dehydrogenase, aconitate hydratase, isocitrate dehydrogenase 3), suggesting that they may be the key differential factors in the process of fructose and sucrose catabolism. Therefore, the changes in gut microbiome mediated by fructose and sucrose are important reasons for their differential effects on host health and metabolism.

Small Intestinal Digestive Functions and Feed Efficiency Differ in Different Pig Breeds

Small intestinal growth and health affect its digestion and absorption ability, while little information exists about the small intestinal morphology and function differences among the different pig breeds. Therefore, 90 healthy 35 days of age Taoyuan black (TB), Xiangcun black (XB), and Duroc (DR) pigs (30 pigs per breed) with similar body weight (BW) of the same breed were reared to 185 days of age to evaluate the potential relationship between feed efficiency and small intestinal morphology and function at 80, 125, and 185 days of age. The results show that the TB and XB pigs had lower initial and final BW, ADG, and ADFI and plasma CHO and LDL-C levels, whereas they had higher plasma LIP levels and jejunal trypsin, invertase, lactase, and maltase activities and higher DM, ADF, Tyr, Arg, and His digestibility at 80 days of age compared with the DR pigs. At 125 days of age, TB and XB pigs had lower apparent total tract digestibility and plasma CHO, HDL-C, LDL-C, and NH3 levels; XB pigs had lower DM and NDF digestibility, and TB pigs had higher jejunal lactase and maltase activities. At 185 days of age, TB and XB pigs had lower DM, EE, ADF, and GE digestibility, while having higher plasma ALT and UN levels; TB pigs had higher plasma AST level and jejunal chymase activity. Furthermore, the plasma free amino acid contents, small intestinal VH, and nutrient transporter expression levels differed at different ages. Therefore, the different pig breeds exhibited significantly different growth performance and small intestinal growth, mainly resulting from the differences in digestive enzymes and nutrient transporters in the small intestine.

Comparison of Digestive Enzyme Activities and Expression of Small Intestinal Transporter Genes in Jinhua and Landrace Pigs

Digestive enzyme activity is involved in the regulation of growth performance because digestive enzymes function to improve the feed efficiency by digestion and in turn to modulate the process of nutrient metabolism. The objective of this study was to investigate the differences of the digestive enzyme activities and expression of nutrient transporters in the intestinal tract between Jinhua and Landrace pigs and to explore the potential breed-specificity in digestion and absorption. The pancreas segments and the digesta and mucosa of the duodenum, jejunum, and ileum were collected from 10 Jinhua pigs and Landrace pigs, respectively. The activities of trypsin, chymotrypsin, amylase, maltase, sucrase, and lipase were measured and the expression levels of PepT1, GLUT2, SGLT1, FABP1, FABP2, and FABP4 were examined. Results showed that the trypsin activity in the pancreas of Jinhua pigs was higher than that in Landrace pigs, but was lower in the small intestine, except for in the jejunal mucosa. The chymotrypsin activity in the small intestine of Jinhua pigs was higher than that in Landrace pigs, except for in jejunal mucosa and contents. Compared with Landrace pigs, the amylase and maltase activity in the small intestine of Jinhua pigs was lower, except for in ileal mucosa. The sucrase activity in the small intestine of Jinhua pigs was also lower than Landrace pigs, except for in jejunal mucosa. Furthermore, the lipase activity in the small intestine of Jinhua pigs was higher than that in Landrace pigs. The mRNA levels of PepT1 and GLUT2 in duodenal, jejunal and ileal mucosa showed no difference between Jinhua and Landrace pigs, whereas SGLT1 in ileal mucosa was lower in Jinhua pigs. The mRNA levels of FABP1, FABP2 and FABP4 in the small intestinal mucosa of Jinhua pigs were higher than in Landrace pigs. These findings indicate that there is a certain difference in the digestibility and absorption of nutrients in small intestine of Jinhua and Landrace pigs, partially resulting in their differences in growth development and fat deposition.

Citrus Extract Improves the Absorption and Utilization of Nitrogen and Gut Health of Piglets

Simple Summary

Weaning can cause weaning stress and reduce the growth performance of piglets. Citrus extract has strong anti-oxidant and anti-inflammatory effects which can improve animal health. The aim of this study was to evaluate the efficacy of citrus extract as a substitute for antibiotics in piglet diets. The results of this study indicate that citrus extract increased the concentrations of plasma essential amino acids, improved intestinal morphology and digestive enzymes activity.

Abstract

The purpose of this study was to investigate the effects of citrus extract (CE) on plasma free amino acids, intestinal morphology and enzymes activity, fecal nitrogen and phosphorus emissions in piglets. The experiment was performed on 144 weaned piglets (Duroc × Landrace × Large White) divided into three groups. Control (CON), fed a basic diet; Antibiotic (ANTI), fed a basic diet supplemented with 75 g/t chlortetracycline; Citrus extract (CE), fed a basic diet supplemented with 300 mL/t CE. The albumin content of the CE group was significantly higher than the CON group. Compared with the CON and ANTI groups, the CE group had increased concentrations of plasma total essential amino acids and threonine. Compared with the CON group, CE increased the α-aminoadipic acid concentration, while compared with ANTI group, it increased the 3-methylhistidine concentration. Compared with the CON group, the crypt depth of duodenum, jejunum and ileum decreased, and the ratio of villus height to crypt depth of ileum increased in the ANTI and CE groups. CE increased the activity of alkaline phosphatase and lipase in duodenum, and the activity of alkaline phosphatase and trypsin in jejunum. In brief, CE improved the absorption and utilization of nitrogen, intestinal morphology and digestive enzymes activity.

Disaccharidase activity in the intestinal tract of Wistar–Furth, diabetes-resistant and diabetes-prone BioBreeding rats

Diabetes-prone BioBreeding (BBdp) rats often present an enteropathy that may precede the onset of autoimmune insulitis. The aim of the present study was to assess the influence of sex, the time course, the strain specificity, the distribution along the intestinal tract and the effect of diet for the changes in the activity of gut invertase, maltase and lactase found in BBdp rats, as compared with both Wistar–Furth (WF) and diabetes-resistant BioBreeding (BBc) rats. These hydrolases were measured, therefore, at day 10, 30, 45, 70, 95 and 120 in three intestinal segments of WF, BBc and BBdp rats fed, after weaning, either a protective high-casein diet, which decreases the incidence of diabetes in the BBdp rats, or one of two diabetogenic diets (National Toxicology Program; NTP or wheat-gluten-based; WG). Except for a somewhat lower lactase activity in the BBdp rats, no obvious difference in hydrolyase activity between the three strains of rats was observed at day 10. Between days 30 and 120, however, the activity of the hydrolases, especially that of invertase and lactase, was lower in the BBdp rats than in either the WF or BBc rats, at least when considering the animals fed either the NTP or WG diet. These findings support the view that BBdp rats exposed to a diabetogenic diet develop an enteropathy well before the onset of autoimmune insulitis, in a manner somehow comparable with the situation found in some type 1 diabetic patients, in whom coeliac disease may be diagnosed before diabetes onset.

Gut permeability and intestinal mucins, invertase, and peroxidase in control and diabetes-prone BB rats fed either a protective or a diabetogenic diet

This study deals with the enteropathy recently identified in diabetes-prone BB rats (BBdp). Diabetes-resistant BB rats (BBc) and BBdp rats were fed from days 32-39 onward either a protective diabetes-retardant hydrolyzed casein diet (HC) or a plant-based diabetogenic (NTP) diet. The NTP diet decreased body weight and plasma insulin in BBc and BBdp rats. The BBdp rats displayed low intestinal invertase and increased intestinal peroxidase activity. In the BBdp rats fed the HC diet, the mucin content 30-35 cm below the pylorus was higher and the gut permeability lower than in the other three rat groups. There was a significant inverse correlation between gut permeability and the insulinogenic index in the BBdp rats fed the HC or NTP diet. Thus, in BBdp rats, the HC diet somehow prevents the increase in gut permeability and the decrease in the insulinogenic index otherwise found in some of these diabetes-prone animals.