Effects of dietary pectin on the profile and transport of intestinal bile acids in young pigs

Abstract

Pectin has been known to lower circulating cholesterol by interacting with bile acid (BA) metabolism. The current study was aimed to investigate intestinal BA transport at the molecular level in a pig model. Twelve young pigs (11.05 ± 0.11 kg) were randomly divided into 2 groups and fed corn-soybean meal diets with either 5% pectin or cornstarch for 72 d. In pigs fed with pectin, total cholesterol and low-density lipoprotein cholesterol (LDL-C) were lowered but high-density lipoprotein (HDL-C) was increased (P < 0.05). Serum triglycerides tended to be lower in the pectin-fed animals (P = 0.093), whereas no change was noted in serum total bile acid. Along the length of the intestine, the size and composition of BA pools vary. The ratio of primary, secondary, taurine-conjugated, and glycine-conjugated BAs in the ileal pool was about 46:15:9:30, whereas it was 28:61:1:11 in the cecum and 22:65:3:9 in the colon (P < 0.05). In the feces, lithocholic acid and ursodeoxycholic acid (UDCA) made up of over 97% of the total BA pool. Overall, the ileum had the greatest expression of farnesoid X receptor (FXR) and apical sodium-coupled bile acid transporter (ASBT) than the duodenum, jejunum, cecum, and colon (P < 0.05), whereas organic solute transporters α/β (OSTα/β) gene expression was peaked in the ileum and jejunum (P < 0.05). Expression multidrug resistance protein 2 (MRP2) gradually decreased towards the end of the intestine (P < 0.05). Greater expression of G protein-coupled bile acid receptor and multidrug resistance protein 3 (MRP3) was found in the cecum and colon (P < 0.05). In pigs fed with 5% pectin, only cecal UDCA (P = 0.097) and hyocholic acid (P = 0.088) showed a decreasing tendency. But FXR, ASBT, and MRP2 were upregulated in the ileum and FXR, OSTα/β, MRP2, and MRP3 in the cecum of PEC-fed pigs (P < 0.05). Liver enzymes involved in BA biosynthesis (CYP7A1, CYP27A1, bile acid-CoA synthase, and bile acid-CoA:amino acid N acyltransferase) were not affected by pectin consumption. In conclusion, the abundant distribution of BA transporters and the greater BA pool size suggests the ileum as the major site for intestinal BA reabsorption in pigs. In the ileum, pectin increased in-and-out BA transport on the apical membrane by increasing ASBT and MRP2, but it increased the overall BA transport in the cecum by increasing OSTα/β and MRP3.

Effects of Activated Charcoal-Herb Extractum Complex on Antioxidant Status, Lipid Metabolites and Safety of Excess Supplementation in Weaned Piglets

“…Increasing concentrations of HDL are strongly associated with decreasing accumulation of atherosclerotic plaques within walls of arteries [39]. Conversely, LDL transports cholesterol from the liver to tissues of the body, and can be oxidized into low-density lipoprotein [40]. Herbs such as Portulaca oleracea reduces triglyceridemia, cholesterolemia, and improves reverse cholesterol transport in rats [41], Gatreh-Samani [42] showed that serum TC, TG and LDL decreased and HDL increased in patients who received 50 or 60 g of Portulaca oleracea per day.…”

Hyodeoxycholic acid (HDCA) suppresses intestinal epithelial cell proliferation through FXR‐PI3K/AKT pathway, accompanied by alteration of bile acids metabolism profiles induced by gut bacteria

“…In brief, about 100 mg of feces were ultrasonic extracted with 1 mL of methanol. The methanol extracts obtained were filtered and analyzed by LC‐MS/MS approach as previous described 32 . BAs were identified by comparison with the retention time of standard substance.…”

Modulation of Pectin on Mucosal Innate Immune Function in Pigs Mediated by Gut Microbiota

“…The detailed experimental design and animals are described in Fang et al [19], and intestinal samples used in the present study were obtained from the same pigs. Briefly, twelve Duroc × Large White crossbred piglets (initial body weight: 11.05 (SD 0.11) kg) were randomly assigned to one of two diets, in a randomized design.…”

“…PEC is found to stimulate growth and activity of bacterial genera, such as Prevotella, Lactobacillus and Faecalibacterium [15][16][17], members of which have been shown to promote gut health [15,18]. In pigs, we recently showed that PEC intake significantly affected ileal and cecal secondary bile acids metabolism, which was closely related to changes in the intestinal microbiota and may have consequences for microbe-host signaling [19]. Many studies have investigated PEC-related alteration in luminal or fecal microbiota; however, we previously showed that alteration of mucosal associated microbiome may be a very important mechanism of PEC effect on immune function [20].…”