Mucosa Of Pigs Research Articles

Effects of supplemental d-methionine in comparison to l-methionine on nitrogen retention, gut morphology, antioxidant status, and mRNA abundance of amino acid transporters in weanling pigs.

An N-balance experiment was conducted to test the hypothesis that d-Methionine (d-Met) has the same bioavailability and efficacy as l-Methionine (l-Met) when fed to weanling pigs. A Met-deficient basal diet containing 0.24% standardized ileal digestible (SID) Met was formulated. Six additional diets were formulated by adding 0.036%, 0.072%, or 0.108% d-Met or l-Met to the basal diet, and these diets, therefore, contained 77%, 87%, or 97% of the requirement for SID Met. Fifty-six barrows (10.53 ± 1.17 kg) were housed in metabolism crates and allotted to the seven diets with eight replicate pigs per diet. Feces and urine were collected quantitatively with 7-d adaptation and 5-d collection periods. Blood and tissue samples from pigs fed the basal diet and pigs fed diets containing 0.108% supplemental Met were collected on the last day. Results indicated that N retention (%) linearly increased (P < 0.01) as supplemental d-Met or l-Met increased in diets. Based on N retention (%) as a response, the linear slope-ratio regression estimated the bioavailability of d-Met relative to l-Met to be 101% (95% confidence interval: 57%-146%). The villus height and crypt depth in the jejunum were not affected by the Met level or Met source. Total antioxidant capacity or thiobarbituric acid reactive substance concentrations in plasma or tissue samples from pigs fed the control diet or diets containing 0.108% supplemental d-Met or l-Met were not different. Abundance of mRNA for some AA transporters analyzed in intestinal mucosa of pigs also did not differ. Therefore, it is concluded that d-Met and l-Met are equally bioavailable for weanling pigs.

Yiqi Jiemin decoction alleviates allergic rhinitis in a guinea pig model by suppressing inflammation, restoring Th1/Th2 balance, and improving cellular metabolism.

We investigated the mechanisms underlying the therapeutic effects of Yiqi Jiemin decoction (YJD), a traditional Chinese medicine (TCM), in the ovalbumin (OVA)-induced allergic rhinitis (AR) model in guinea pigs. YJD significantly decreased infiltration of mast cells and eosinophils into the nasal mucosa of AR model guinea pigs. YJD also increased expression of TGF-β in the nasal mucosa, restored the balance of Th1/Th2 immune cell responses, and decreased serum levels of various pro-inflammatory mediators, including histamine (HA), neuropeptide Y (NPY), acetylcholine (ACH), norepinephrine and immunoglobulin E (IgE). Metabolic analyses using liquid chromatography coupled with high-resolution mass spectrometry revealed that YJD improved cellular metabolism in AR model guinea pigs and increased serum levels of glycocholic acid while decreasing levels 1-palmitoyl lysophosphatidic acid. RNA-sequencing analysis identified BPIFB2 as a potential diagnostic biomarker and therapeutic target for AR. Functional enrichment analyses showed that YJD significantly inhibited cytokine secretion pathways in AR model guinea pigs. These findings demonstrate that YJD protects against OVA-induced AR in guinea pigs by suppressing inflammation in the nasal mucosa, restoring Th1/Th2 balance, and improving cellular metabolism.

Prevotella-rich enterotype may benefit gut health in finishing pigs fed diet with a high amylose-to-amylopectin ratio.

To investigate the influence of baseline enterotypes and dietary starch type on the concentration of short-chain fatty acids (SCFA), numbers of butyrate producing bacteria and the expression of genes related to intestinal barrier and inflammatory response in the colon of finishing pigs, a 60-d in vivo trial was conducted. A 2-wk pre-trial with 102 crossbred (Duroc × [Landrace × Yorkshire]) finishing barrows (90 d old) was conducted to screen enterotypes. Then, a total of 32 pigs (87.40 ± 2.76 kg) with high (HPBR, ≥ 14) and low (LPBR, ≤ 2) Prevotella-to-Bacteroides ratios (PBR) in equal measure were selected and randomly divided into 4 groups with 8 replicates per group and 1 pig per replicate. The trial was designed following a 2 (PBR) × 2 (amylose-to-amylopectin ratio, AMR) factorial arrangement. Pigs with different PBR were fed diets based on corn-soybean meal with high AMR (HAMR, 1.24) or low AMR (LAMR, 0.23), respectively. Results showed that neither PBR nor AMR influenced the growth performance of pigs. HPBR pigs fed HAMR diet had a higher number of colonic Clostridium cluster XIVa and higher gene expression of butyrate kinase compared to the LPBR pigs (P < 0.05). The HPBR pigs fed HAMR diets also had increased colonic concentrations of total SCFA and propionate compared to the LPBR pigs (P < 0.05). Comparing with other pigs, HPBR pigs fed HAMR diets showed a lower (P < 0.05) expression of histone deacetylases (HDAC) gene and higher (P < 0.05) expression of G protein-coupled receptor 43 gene (GPR 43) in the colonic mucosa. The interaction (P < 0.05) of HPBR and HAMR was also found to decrease the gene expression of interleukin (IL)-6, IL-12, IL-1β and tumor necrosis factor-α (TNF-α) in colonic mucosa. These findings show that HAMR diet increased the abundance and activity of butyrate-producing bacteria and the concentration and absorption of SCFA, which may be associated with the decreased gene expression of inflammatory cytokines in the colonic mucosa of pigs with Prevotella-rich enterotype. All these alterations are likely to have a positive effect on the intestinal health of finishing pigs.

Xylanase modulates the microbiota of ileal mucosa and digesta of pigs fed corn-based arabinoxylans likely through both a stimbiotic and prebiotic mechanism.

The experimental objective was to characterize the impact of insoluble corn-based fiber, xylanase, and an arabinoxylan-oligosaccharide on ileal digesta and mucosa microbiome of pigs. Three replicates of 20 gilts were blocked by initial body weight, individually-housed, and assigned to 1 of 4 dietary treatments: a low-fiber control (LF), a 30% corn bran high-fiber control (HF), HF+100 mg/kg xylanase (HF+XY), and HF+50 mg/kg arabinoxylan oligosaccharide (HF+AX). Gilts were fed their respective treatments for 46 days. On day 46, pigs were euthanized and ileal digesta and mucosa were collected. The V4 region of the 16S rRNA was amplified and sequenced, generating a total of 2,413,572 and 1,739,013 high-quality sequences from the digesta and mucosa, respectively. Sequences were classified into 1,538 mucosa and 2,495 digesta operational taxonomic units (OTU). Hidden-state predictions of 25 enzymes were made using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States 2 (PICRUST2). Compared to LF, HF increased Erysipelotrichaceae_UCG-002, and Turicibacter in the digesta, Lachnospiraceae_unclassified in the mucosa, and decreased Actinobacillus in both (Q<0.05). Relative to HF, HF+XY increased 19 and 14 of the 100 most abundant OTUs characterized from digesta and mucosa, respectively (Q<0.05). Notably, HF+XY increased the OTU_23_Faecalibacterium by nearly 6 log2-fold change, compared to HF. Relative to HF, HF+XY increased genera Bifidobacterium, and Lactobacillus, and decreased Streptococcus and Turicibacter in digesta (Q<0.05), and increased Bifidobacterium and decreased Escherichia-Shigella in the mucosa (Q<0.05). Compared to HF, HF+AX increased 5 and 6 of the 100 most abundant OTUs characterized from digesta and mucosa, respectively, (Q<0.05), but HF+AX did not modulate similar taxa as HF+XY. The PICRUST2 predictions revealed HF+XY increased gene-predictions for enzymes associated with arabinoxylan degradation and xylose metabolism in the digesta, and increased enzymes related to short-chain fatty acid production in the mucosa. Collectively, these data suggest xylanase elicits a stimbiotic and prebiotic mechanism.

Hydrolytic Degradation of Heparin in Acidic Environments: Nuclear Magnetic Resonance Reveals Details of Selective Desulfation.

Heparin is a complex glycosaminoglycan, derived mainly from pig mucosa, used therapeutically for its anticoagulant activity. Yet, owing largely to the chain complexity, the progressive effects of environmental conditions on heparin structure have not been fully described. A systematic study of the influence of acidic hydrolysis on heparin chain length and substitution has therefore been conducted. Changes in the sulfation pattern, monitored via 2D NMR, revealed initial de-N-sulfation of the molecule (pH 1/ 40 °C) and unexpectedly identified the secondary sulfate of iduronate as more labile than the 6-O-sulfate of glucosamine residues under these conditions (pH 1/ 60 °C). Additionally, the loss of sulfate groups, rather than depolymerization, accounted for most of the reduction in molecular weight. This provides an alternative route to producing partially 2-O-de-sulfated heparin derivatives that avoids using conventional basic conditions and may be of value in the optimization of processes associated with the production of heparin pharmaceuticals.

Detection of Helicobacter suis bacteria in pigs of different age groups

Currently, the pathogenesis of gastric ulcer in pigs remains largely unexplored. The origin of this pathology is most often associated with the type and the technologies of feeding, stresses and disorders of homeostasis of the animal body. The possible involvement of bacteria of the genus Helicobacter in the development of chronic gastritis and gastric ulcer disease in pigs was suggested by the researchers relatively recently. The article comprises the results of investigations aimed at detection of Helicobacter suis bacteria and the contamination degree of porcine gastric mucosa in pigs of different age groups. The stomachs, obtained from suckling pigs, fattening pigs and sows in the slaughterhouse of the Mari El Republic, were examined. The study determined the dependence of pathomorphological changes in the gastric mucosa of pigs on the detection of H. suis in microscopic and biochemical tests as well as in PCR. Thus, no pathomorphological changes in the gastric mucosa of suckling pigs were detected. Severe hyperkeratosis, erosions, and ulcers were found on the stomach mucosa of fattening pigs and sows that were infected with H. suis bacteria. Sows also had ulcerative lesions in the non-glandular region of esophagus. In the biomaterial of suckling piglets the DNA of H. suis bacteria was found only in the pyloric region of the stomach, while in fattening pigs, the DNA of these bacteria was most often isolated from the fundal region, and in sows – from the fundal and cardial regions. This indicates a shift in colonization by helicobacters of the mucous membrane of the stomach from the pyloric to the cardiac sectionincreased with animal age. The obtained research data provide the additional evidence of the etiological role of H. suis in the pathogenesis of gastric ulcer in pigs.

Histopathological Effects of Boric Acid Solution on Middle Ear Mucosa in Guinea Pigs

Histopathological Effects of Boric Acid Solution on Middle Ear Mucosa in Guinea Pigs

Histochemical Assessment of Mucin-Secreting Cells from the Gastric Mucosa of Guinea Pigs

Stomach fragments from 3 guinea pigs were collected from the three regions: cardiac, fundic and pyloric, for histochemical investigations. The anatomical segments were processed by the classical method of inclusion in paraffin and the histological sections were stained with PAS reaction for highlighting the neutral mucins and the Alcian blue method for acid mucins. All the surface cells of the gastric mucosa and in the crypts were positive on the PAS reaction and negative in the case of the alcian blue reaction. This demonstrates that cells on the surface and in the crypts synthetize neutral mucins. In the case of the cardiac region glands, only a small number of cells were positive on the two histochemical reactions, which shows that the cardiac glands in guinea pig synthesize a very small amount of neutral and acidic mucins. There are no positive cells in neither reaction used in the fundic glands case, which shows that these glands do not synthesize mucins, neither neutral nor acidic content. The glands located in the pyloric region have cells in the deep half of the wall which were positive on both histochemical reactions, which shows that they synthesize both neutral mucins and acidic mucins.

ZNF263 is a transcriptional regulator of heparin and heparan sulfate biosynthesis

Heparin is the most widely prescribed biopharmaceutical in production globally. Its potent anticoagulant activity and safety makes it the drug of choice for preventing deep vein thrombosis and pulmonary embolism. In 2008, adulterated material was introduced into the heparin supply chain, resulting in several hundred deaths and demonstrating the need for alternate sources of heparin. Heparin is a fractionated form of heparan sulfate derived from animal sources, predominantly from connective tissue mast cells in pig mucosa. While the enzymes involved in heparin biosynthesis are identical to those for heparan sulfate, the factors regulating these enzymes are not understood. Examination of the promoter regions of all genes involved in heparin/heparan sulfate assembly uncovered a transcription factor-binding motif for ZNF263, a C2H2 zinc finger protein. CRISPR-mediated targeting and siRNA knockdown of ZNF263 in mammalian cell lines and human primary cells led to dramatically increased expression levels of HS3ST1, a key enzyme involved in imparting anticoagulant activity to heparin, and HS3ST3A1, another glucosaminyl 3-O-sulfotransferase expressed in cells. Enhanced 3-O-sulfation increased binding to antithrombin, which enhanced Factor Xa inhibition, and binding of neuropilin-1. Analysis of transcriptomics data showed distinctively low expression of ZNF263 in mast cells compared with other (non-heparin-producing) immune cells. These findings demonstrate a novel regulatory factor in heparan sulfate modification that could further advance the possibility of bioengineering anticoagulant heparin in cultured cells.

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

The use of prebiotics to regulate gut microbiota is a promising strategy to improve gut health. Pectin (PEC) is a prebiotic carbohydrate that enhances the health of the gut by promoting the growth of beneficial microbes. These microbes produce metabolites that are known to improve mucosal immune responses. This study was conducted to better understand effects of PEC on the microbiome and mucosal immunity in pigs. Pigs were fed two diets, with or without 5% apple PEC, for 72 days. Effects of PEC on the microbiota, cytokine expression, short-chain fatty acids (SCFAs) concentration and barrier function were examined in the ileum and cecum of the pigs. An integrative analysis was used to determine interactions of PEC consumption with bacterial metabolites and microbiome composition and host mucosal responses. Consumption of PEC reduced expression of pro-inflammatory cytokines such as IFN-γ, IL-6, IL-8, IL-12 and IL-18, and the activation of the pro-inflammatory NF-κB signaling cascade. Expression of MUC2 and TFF and the sIgA content was upregulated in the mucosa of PEC-fed pigs. Network analysis revealed that PEC induced significant interactions between microbiome composition in the ileum and cecum on mucosal immune pathways. PEC-induced changes in bacterial genera and fermentation metabolites, such as Akkermansia, Faecalibacterium, Oscillibacter, Lawsonia and butyrate, correlated with the differentially expressed genes and cytokines in the mucosa. In summary, the results demonstrate the anti-inflammatory properties of PEC on mucosal immune status in the ileum and cecum effected through modulation of the host microbiome.

Tussilagone inhibits allergic responses in OVA-induced allergic rhinitis guinea pigs and IgE-stimulated RBL-2H3 cells

Farfarae Flos is the dried flower buds of Tussilago farfara L. which is widely used to treat allergic and inflammatory diseases in Chinese folk. Tussilagone (TSL), a sesquiterpene compound purified from Farfarae Flos, has been confirmed the main active component in the plant. However, its anti-allergic activity hasn't been reported yet. The purpose of this study is to investigate the anti-allergic effect of TSL in ovalbumin (OVA)-induced allergic rhinitis (AR) guinea pigs and immunoglobulin E (IgE)-stimulated RBL-2H3 cells. The AR symptoms such as nasal scratching, sneezing and runny nose were scored and the histological changes of nasal mucosa were observed by H&E staining. The levels of histamine, OVA-specific IgE, IL-6 and TNF-α in the serum were measured by ELISA. In IgE-stimulated RBL-2H3 cells, the phosphoryration of Lyn, Syk, Akt, NF-κB p65, ERK and p38 MAPK were investigated by western blot analysis. The results showed that intraperitoneal injection of TSL at doses of 25 and 50 mg/kg significantly alleviated the allergic symptoms and the histological changes of nasal mucosa in OVA-induced allergic rhinitis guinea pigs. Moreover, the levels of histamine, IgE and IL-6 in the serum decreased significantly (p < .05). In vitro, TSL suppressed the phosphorylation of Lyn, Syk, Akt, NF-κB p65, ERK and p38 MAPK in IgE-stimulated RBL-2H3 cells. These results indicate TSL has therapeutic effect on allergic rhinitis in guinea pigs. The anti-allergic mechanism may be through the inhibition of allergic and inflammatory related pathways in mast cells.

Recombinant adenovirus carrying a core neutralizing epitope of porcine epidemic diarrhea virus and heat-labile enterotoxin B of Escherichia coli as a mucosal vaccine.

Porcine epidemic diarrhea virus (PEDV) targets the intestinal mucosa in pigs. To protect against PEDV invasion, a mucosal vaccine is utilized effectively. In this study, we generated a recombinant adenovirus vaccine encoding the heat-labile enterotoxin B (LTB) and the core neutralizing epitope (COE) of PEDV (rAd-LTB-COE). The fusion protein LTB-COE was successfully expressed by the recombinant adenovirus in HEK293 cells, and the immunogenicity of the vaccine candidate was assessed in BALB/c mice and piglets. Three intramuscular or oral vaccinations with rAd-LTB-COE at two-week intervals induced robust humoral and mucosal immune responses. Moreover, a cell-mediated immune response was promoted in immunized mice, and the neutralizing antibody inhibited both the vaccine strain and the emerging PEDV isolate. Immunization experiments in piglets revealed that rAd-LTB-COE was immunogenic and induced good immune responses in piglets. Further studies are required to evaluate the efficacy of rAd-LTB-COE against a highly virulent PEDV challenge.

137 Effects of dietary supplementation with xylanase and probiotics on growth performance and gut health of newly weaned pigs

Abstract This study was to evaluate the supplemental effects of xylanase and probiotics on growth performance and gut health of newly weaned pigs. One hundred and forty-four pigs at 3 weeks of age with an initial body weight (BW) at 6.47 ± 0.03 kg were allotted (4 pigs per pen) to 3 dietary treatments based on a randomized complete block design with sex (gilts and barrow) and initial BW as blocks. The treatments were CON (no supplement), XYL (xylanase at 10,000 XU/kg, Xylamax, BRI, Durham, NC), and PRO (Bacillus spp. 6 x 109 CFU/kg plus xylanase 10,000 XU/kg, EnzaPro, BRI). All diets met the NRC (2012) requirements in 3 phases (P1 for 7 d, P2 for 14 d, and P3 for 14 d). The ADG, ADFI, and G/F were measured weekly. On d 21, 1 pig representing a median BW of each pen was euthanized to collect jejunal samples to measure the immune and oxidative stress status, microbiome, and histology. Data were analyzed using the MIXED procedure of SAS. Treatment was a fixed effect and blocks were random effects. There were no fixed effects among treatments on growth performance, immune and oxidative stress status, and histology. Use of xylanase increased (P &amp;lt; 0.05) the Chao1 index in jejunal mucosa of pigs (24.6 to 29.5). Relative abundance of the Enterobacteriaceae in jejunal mucosa tended to decrease (P = 0.083) with the use of xylanase (16.2 to 1.6%). The PRO increased (P &amp;lt; 0.05) the relative abundance of Mitsuokella compared with others treatments (0.9 vs. 4.8%). In conclusion, supplementation of xylanase or Mitsuokella can enhance the microbiome in jejunal mucosa by increasing the diversity and beneficial bacterial abundance, whereas by reducing pathogenic bacterial abundance without affecting the growth performance, histology, immune, and oxidative stress status.

Isolation and Identification of Porcine Epidemic Diarrhea Virus and Its Effect on Host Natural Immune Response.

Porcine epidemic diarrhea (PED) is a highly infectious intestinal disease caused by porcine epidemic diarrhea virus (PEDV). A PEDV strain was isolated from the piglet intestinal tract in Vero cells in Jiangsu Province, designated as the JS-A strain. PEDV was identified as the isolated virus by cytopathology, immunofluorescence assay, western blotting, transmission electron microscopy, and sequence analysis. The full-length genome of the JS-A isolate and the S gene were systematically analyzed, indicating that PEDV JS-A belongs to the G2a subtype, which is closely related to the prevalent PEDV in many countries and different from many current vaccines. Animal regression tests showed that piglets that are orally infected with the virus continue to develop diarrhea with yellowish and unpleasant odors. Further, piglets showed reduced food consumption and weight loss in the challenged group, while there were no abnormalities in the control group. In addition, Toll-like receptors (TLRs), RIG-I, and the downstream medium gene in the intestinal mucosa of newborn pigs infected with PEDV JS-A strain were studied. The neonatal Fc receptor (FcRn) was the only IgG transport receptor and protected IgG from degradation. Therefore, PEDV JS-A infection might inhibit FcRn expression by down-regulating TLRs and downstream signaling molecules. Taken together, isolation of the JS-A variant contributes to evolutionary analysis of the diarrhea virus. Further, the experimental infection model lays a foundation for further research related to vaccine development and the antiviral natural immune response of infected piglets, which helps us to better understand PEDV pathogenesis and immune mechanism.

Post-natal Growth Retardation Associated With Impaired Gut Hormone Profiles, Immune and Antioxidant Function in Pigs.

The factors that cause post-natal growth retardation (PGR) in pigs are complicated; however, metabolic and immune system impairment seem to be involved. The purpose of this study was to investigate the changes of blood parameters, hormone profiles, antioxidant capacity, and immune responses in PGR pigs. Blood and small intestinal mucosa samples were collected from 42-days-old PGR and healthy pigs. The results showed that compared with the healthy group, the relative weight of spleen and kidney were greater, but the liver was lighter in PGR pigs (P < 0.05). The PGR pigs had increased serum alanine transaminase, urea nitrogen, blood ammonia, IgG, and complement 4, but decreased glucose and albumin (P < 0.05). The higher levels of serum leptin (LEP) and thyroxin (T4), and the lower levels of insulin-like growth factor-1 (IGF-1), 5-hydroxytryptamine (5-HT), somatostatin (SS), and agouti gene-related protein (AgRP) were observed in PGR pigs (P < 0.05). Consistent with the serum levels of hormones, the mRNA levels of gut hormones and their receptors were also altered in intestinal mucosa from PGR pigs (P < 0.05). The PGR pigs exhibited higher plasma concentrations of interleukin-1β (IL-1β), IL-6, IL-8, and transformed growth factor beta (TGFβ) (P < 0.05). However, the mRNA expressions of several cytokines were lower in the small intestinal mucosa of PGR pigs (P < 0.05). Abnormal antioxidant indexes in serum of PGR pigs were observed, which was in accordance with the reduced mRNA expression of several anti-oxidative genes in the small intestinal mucosa of PGR pigs (P < 0.05). These data demonstrate that an abnormal gut hormone system, immune dysfunction, and decreased antioxidant capacity may contribute to PGR in pigs. These changes could provide a valuable target in the regulation of post-natal growth retardation in animals and humans.

Influence of supplemented coated-cysteamine on morphology, apoptosis and oxidative stress status of gastrointestinal tract

BackgroundCysteamine was coated to cover its odor and maintain the stability. However, coated cysteamine (CC) has not been clearly evaluated for its effects on the gastrointestinal mucosa status. We hypothesize that the appropriate CC supplementation in diet impacts the stomach and intestinal mucosa variously through regulating the morphology, apoptosis, and oxidative stress status in model of pigs.ResultsThe results showed that villus height increased (P < 0.05), and crypt depth decreased (P < 0.05) in the ileum when pigs were fed the diet with low cysteamine (LCS) compared with the control diet. The ileal lesion score in the LCS group was significantly (P < 0.01) lower than that in the control group, while the gastric lesion score in the CC group was significantly (P < 0.01) higher compared with that of the control group. It also showed that the activities of total superoxide dismutase (T-SOD) and diamine oxidase (DAO) were upregulated (P < 0.05) in the LCS group. In addition, Bax and caspase 3 immunore-activity increased (P < 0.01), and Bcl-2 immunoreactivity decreased (P < 0.01) in the gastric mucosa of pigs fed the diet with high cysteamine (HCS). The Bax and caspase 3 immunoreactivity decreased (P < 0.01), and Bcl-2 immunoreactivity increased (P < 0.01) in ileum mucosa of pigs fed the HCS diet.ConclusionsAlthough moderate dietary coated cysteamine showed positive effects on GI mucosal morphology, apoptosis, and oxidative stress status, the excess coated cysteamine may cause apoptosis leading to GI damage in pigs.

Transcriptomic Responses in the Livers and Jejunal Mucosa of Pigs under Different Feeding Frequencies.

Simple SummaryNutrition management strategies are closely related to body development and health, and feeding frequency affects pig feed intake, feed efficiency, body composition, and growth performance. However, the effect of feeding one time daily and two times daily on the intestine has been given less attention. In this study, we investigated the transcriptomic responses induced in the livers and jejunal mucosa of growing pigs by daily feeding schedules. We found that when compared with feeding once daily, two times feeding had no significant effect on the growth performance of growing pigs with the same average daily feed intake. A two meals regimen reduced the concentration of triglycerides in serum and liver, affected the body metabolism by promoting lipid transport, lipogenesis, fatty acid oxidation, chylomicron formation and transport, gluconeogenesis, and inhibiting adipocyte differentiation. These findings support the idea that different feeding regimens could affect lipid metabolism and can be effective in nutritional strategies against metabolic dysfunction.Feeding frequency in one day is thought to be associated with nutrient metabolism and the physical development of the body in both experimental animals and humans. The present study was conducted to investigate transcriptomic responses in the liver and jejunal mucosa of pigs to evaluate the effects of different feeding frequencies on the body’s metabolism. Twelve Duroc × Landrance × Yorkshire growing pigs with an average initial weight (IW) of 14.86 ± 0.20 kg were randomly assigned to two groups: feeding one time per day (M1) and feeding two times per day (M2); each group consisted of six replicates (pens), with one pig per pen. During the one-month experimental period, pigs in the M1 group were fed on an ad libitum basis at 8:00 am; and the M2 group was fed half of the standard feeding requirement at 8:00 am and adequate feed at 16:00 pm. The results showed that average daily feed intake, average daily gain, feed:gain, and the organ indices were not significantly different between the two groups (p > 0.05). The total cholesterol (T-CHO), triglyceride (TG), high-density lipoprotein-cholesterol (HDL-C), and low-density lipoprotein-cholesterol (LDL-C) concentrations in the serum, and the TG concentration in the liver in the M2 groups were significant lower than those in the M1 group, while the T-CHO concentration in the liver were significant higher in the M2 group (p < 0.05). Jejunal mucosa transcriptomic analysis showed the gene of Niemann-Pick C1-Like 1 (NPC1L1), Solute carrier family 27 member 4 (SLC27A4), Retinol binding protein 2 (RBP2), Lecithin retinol acyltransferase (LRAT), Apolipoprotein A (APOA 1, APOA 4, APOB, and APOC 3) were upregulated in the M2 group, indicating that fat digestion was enhanced in the small intestine, whereas Perilipin (PLIN1 and PLIN2) were downregulated, indicating that body fat was not deposited. Fatty acid binding proteins (FABPs) and Acetyl-CoA acyltransferase 1 (ACAA1) were upregulated in the M2 group, indicating that two times feeding daily could promote the oxidative decomposition of fatty acids. In conclusion, under the conditions in this study, the feeding frequency had no significant effect on the growth performance of pigs, but affected the body’s lipid metabolism, and the increase of feeding frequency promoted the fat digestion in the small intestine and the oxidative decomposition of fatty acids in the liver.

Original low birth weight deteriorates the hindgut epithelial barrier function in pigs at the growing stage.

The deteriorative effect of low birth weight (LBW) on the mucosal permeability of the small intestine in piglets has been widely confirmed. However, whether the hindgut epithelial barrier function in LBW pigs is deteriorated during the growing stage is still unclear. Our study investigated differences in the hindgut epithelial barrier function between LBW and normal birth weight pigs during the growing stage (d 90). Our data demonstrated that the hindgut epithelium of LBW pigs has a high histopathological score, accompanied by decreased antioxidant capacity and increased apoptosis rate, as well as elevated expression and activity of caspase-3. In addition, the number of intestinal goblet cells and gene expression of mucin 2 were significantly down-regulated in LBW pigs. The expression of tight junction proteins (ZO-1 and occludin) was markedly inhibited by the LBW. The mRNA abundance of inflammatory cytokines such as TNF-α, IL-1β, and IL-8 was significantly increased in the hindgut mucosa of LBW pigs. Furthermore, our data revealed that LBW altered the intestinal microbial community in the hindgut mucosa of pigs. Collectively, these finding add to our understanding of the mechanisms responsible for hindgut epithelial barrier dysfunction in LBW pigs during the growing stage and facilitate the development of nutritional intervention strategies.-Tao, S., Bai, Y., Li, T., Li, N., Wang, J. Original low birth weight deteriorates the hindgut epithelial barrier function in pigs at the growing stage.

Effects of porcine epidemic diarrhea virus infection on tight junction protein gene expression and morphology of the intestinal mucosa in pigs.

Tight junction proteins are important for the maintenance and repair of the intestinal mucosal barrier. The present study investigated relationships among tight junction protein gene expression, porcine epidemic diarrhea virus (PEDV) infection, and intestinal mucosal morphology in piglets. We compared the expression of six tight junction proteins (ZO-1, ZO-2, Occludin, Claudin-1, Claudin-4, and Claudin-5) between seven-day-old piglets infected with PEDV and normal piglets, as well as in PEDV-infected porcine intestinal epithelial cells (IPEC-J2). We also evaluated differences in mucosal morphology between PEDV-infected and normal piglets. The expression of six tight junction protein genes was lower in PEDV-infected piglets than in the normal animals. The expression of ZO-1, ZO-2, Occludin, and Claudin-4 in the intestine tissue was significantly lower (p⟨0.05) in PEDV-infected than in normal piglets. The expression of Claudin-5 in the jejunum was significantly lower in PEDV-infected piglets than in the normal animals (p⟨0.01). The expression of Claudin-1 and Claudin-5 genes in the ileum was significantly higher in PEDV-infected piglets than in normal piglets (p⟨0.01). Morphologically, the intestinal mucosa in PEDV-infected piglets exhibited clear pathological changes, including breakage and shedding of intestinal villi. In PEDV-infected IPEC-J2 cells, the mRNA expression of the six tight junction proteins showed a downward trend; in particular, the expression of the Occludin and Claudin-4 genes was significantly lower (p⟨0.01). These data suggest that the expression of these six tight junction proteins, especially Occludin and Claudin-4, plays an important role in maintaining the integrity of the intestinal mucosal barrier and resistance to PEDV infection in piglets.

The expression of TAP1 candidate gene, but not its polymorphism and methylation, is associated with colonic polyp formation in a porcine model of human familial adenomatous polyposis

In humans, the dysfunction of the adenomatous polyposis coli (APC) gene causes hereditary familial adenomatous polyposis (FAP) and increased risk of colorectal cancer (CRC). The severity of polyposis varies between individuals, but genetic basis for this is in large part unknown. This variability also occurs in our porcine model of FAP, based on an APC1311 mutation (orthologous to human APC1309). Since loss of TAP1 function can lead to CRC in humans, we searched for germline polymorphisms in APC1311/+ pigs with low (LP) and high (HP) levels of polyposis, as well as in wild-type pigs representing six breeds and a commercial line. The distribution of 40 identified polymorphic variants was similar in the LP and HP pigs. In contrast, the TAP1 transcript level was significantly higher in normal colon mucosa of HP pigs than in LP pigs. Moreover, six SNPs showed significant effects on TAP1 promoter activity, but no correlation with severity of polyposis was observed. Analysis of DNA methylation in the promoter region showed that one CpG site differed significantly between LP and HP pigs. We conclude that TAP1 genotype may not itself be associated with polyposis, but our findings concerning its expression suggest a role in the development of polyps.