Possible association of G6PC2 and MUC6 induced by low­dose­rate irradiation in mouse intestine with inflammatory bowel disease.

Although there are several types of radiation exposure, it is debated whether low­dose­rate (LDR) irradiation (IR) affects the body. Since the small intestine is a radiation­sensitive organ, the present study aimed to evaluate how it changes when exposed to LDR IR and identify the genes sensitive to these doses. After undergoing LDR (6.0 mGy/h) γ radiation exposure, intestinal RNA from BALB/c mice was extracted 1 and 24 h later. Mouse whole genome microarrays were used to explore radiation­induced transcriptional alterations. Reverse transcription­quantitative (RT­q) PCR was used to examine time­ and dose­dependent radiation responses. The histopathological status of the jejunum in the radiated mouse was not changed by 10 mGy of LDR IR; however, 23 genes were upregulated in response to LDR IR of the jejunum in mice after 1 and 24 h of exposure. Upregulated genes were selected to validate the results of the RNA sequencing analysis for RT­qPCR detection and results showed that only Na+/K+ transporting subunit α4, glucose­6­phosphatase catalytic subunit 2 (G6PC2), mucin 6 (MUC6) and transient receptor potential cation channel subfamily V member 6 levels significantly increased after 24 h of LDR IR. Furthermore, G6PC2 and MUC6 were notable genes induced by LDR IR exposure according to protein expression via western blot analysis. The mRNA levels of G6PC2 and MUC6 were significantly elevated within 24 h under three conditions: i) Exposure to LDR IR, ii) repeated exposure to LDR IR and iii) exposure to LDR IR in the presence of inflammatory bowel disease. These results could contribute to an improved understanding of immediate radiation reactions and biomarker development to identify radiation­susceptible individuals before histopathological changes become noticeable. However, further investigation into the specific mechanisms involving G6PC2 and MUC6 is required to accomplish this.

Antispasmodic and antidiarrheal effects of Juniperus oxycedrus L. on the jejunum in rodents.

Functional bowel disorders (FBD) have a major potential to degrade the standards of public life. Juniperus oxycedrus L. (J. oxycedrus) (Cupressaceae) has been described as a plant used in traditional medicine as an antidiarrheal medication. The present study is the first to obtain information on the antispasmodic and antidiarrheic effects of J. oxycedrus aqueous extract through in vitro and in vivo studies. An aqueous extract of J. oxycedrus (AEJO) was extracted by decoctioning air-dried aerial sections of the plant. Antispasmodic activity was tested in an isolated jejunum segment of rats exposed to cumulative doses of drogue extract. The antidiarrheic activity was tested using diarrhea caused by castor oil, a transit study of the small intestine, and castor oil-induced enteropooling assays in mice. In the jejunum of rats, the AEJO (0.1, 0.3 and 1 mg/ml) diminished the maximum tone induced by low K+ (25 mM), while it exhibited a weak inhibitory effect on high K+ (75 mM) with an IC50=0.49 ± 0.01 mg/ml and IC50=2.65 ± 0.16 mg/ml, respectively. In the contractions induced by CCh (10-6 M), AEJO diminished the maximum tone, similar to that induced by low K+ (25 mM). with an IC50=0.45 ± 0.02 mg/ml. The inhibitory effect of AEJO on low K+ induced contractions was significantly diminished in the presence of glibenclamide (GB) (0.3 µM) and 4-aminopyrimidine (4-AP) (100 µM), with IC50 values of 1.84 ± 0.09 mg/ml. and 1.63 ± 0.16 mg/ml, respectively). The demonstrated inhibitory effect was similar to that produced by a non-competitive antagonist acting on cholinergic receptors and calcium channels. In castor oil-induced diarrhea in mice, AEJO (100, 200, and 400 mg/kg) caused an extension of the latency time, a reduced defecation frequency, and a decrease in the amount of wet feces compared to the untreated group (distilled water). Moreover, it showed a significant anti-motility effect and reduced the amount of fluid accumulated in the intestinal lumen at all tested doses. These findings support the conventional use of Juniperus oxycedrus L. as a remedy for gastrointestinal diseases.

Infant milk formula, produced by membrane filtration, promotes mucus production in the upper small intestine of young pigs.

Human breast milk promotes maturation of the infant gastrointestinal barrier, including the promotion of mucus production. In the quest to produce next generation infant milk formula (IMF), we have produced IMF by membrane filtration (MEM-IMF). With a higher quantity of native whey protein, MEM-IMF more closely mimics human breast milk than IMF produced using conventional heat treatment (HT-IMF). After a 4-week dietary intervention in young pigs, animals fed a MEM-IMF diet had a higher number of goblet cells, acidic mucus and mucin-2 in the jejunum compared to pigs fed HT-IMF (P < 0.05). In the duodenum, MEM-IMF fed pigs had increased trypsin activity in the gut lumen, increased mRNA transcript levels of claudin 1 in the mucosal scrapings and increased lactase activity in brush border membrane vesicles than those pigs fed HT-IMF (P < 0.05). In conclusion, MEM-IMF is superior to HT-IMF in the promotion of mucus production in the young gut.

Protective effect of Broussonetia papyrifera leaf polysaccharides on intestinal integrity in a rat model of diet-induced oxidative stress.

This study aimed to investigate the effect of Broussonetia papyrifera polysaccharides (BPP) on the jejunal intestinal integrity of rats ingesting oxidized fish oil (OFO) induced oxidative stress. Polysaccharides (Mw 16,956 Da) containing carboxyl groups were extracted from Broussonetia papyrifera leaves. In vitro antioxidant assays showed that this polysaccharide possessed antioxidant capabilities. Thirty-two male weaned rats were allocated into two groups orally infused BPP solution and PBS for 26 days, respectively. From day 9 to day 26, half of the rats in each group were fed food containing OFO, where the lipid peroxidation can induce intestinal oxidative stress. OFO administration resulted in diarrhea, decreased growth performance (p < 0.01), impaired jejunal morphology (p < 0.05) and antioxidant capacity (p < 0.01), increased the levels of ROS and its related products, IL-1ß and IL-17 (p < 0.01) of jejunum, as well as down-regulated Bcl-2/Bax (p < 0.01) and Nrf2 signaling (p < 0.01) of jejunum in rats. BPP gavage effectively alleviated the negative effects of OFO on growth performance, morphology, enterocyte apoptosis, antioxidant capacity and inflammation of jejunum (p < 0.05) in rats. In the oxidative stress model cell assay, the use of receptor inhibitors inhibited the enhancement of antioxidant capacity by BPP. These results suggested that BPP protected intestinal morphology, thus improving growth performance and reducing diarrhea in rats ingesting OFO. This protective effect may be attributed to scavenging free radicals and activating the Nrf2 pathway, which enhances antioxidant capacity, consequently reducing inflammation and mitigating intestinal cell death.

Multitissue transcriptomics demonstrates the systemic physiology of methionine deficiency in broiler chickens.

Methionine (Met) supplementation is common practice in broilers to support nutrition, yet there are gaps in the understanding of its role in systemic physiology. Furthermore, several different Met sources are available that may have different physiological effects. This study evaluated the mode of action of Met deficiency (no Met-supplementation) and supplementation (0.25% DL- or L-Met, 0.41% liquid methionine hydroxy analog-free acid (MHA-FA)), and of Met source (DL-, L- or MHA-FA) in broiler chickens, via host transcriptomics. Biological pathway activation modeling was performed to predict the likely phenotypic effects of differentially expressed genes (DEGs) in tissue samples from the jejunum, liver and breast obtained at 10, 21 and 34/35 d of age from three experiments in a combined analysis. Animal performance data showed that Met deficiency reduced BW, daily BW gain, daily feed intake, and breast yield, and increased feed conversion ratio in all experiments (P < 0.05). Effects of Met deficiency on gene expression were least evident in the jejunum and most evident in the liver and breast, as evidenced by the number of DEG and activated pathways. Activated pathways suggested Met deficiency was associated with inhibited protein turnover, gut barrier integrity, and adaptive immunity functions in the jejunum, that predicted reduced breast yield. There was an interaction with age; in Met-deficient birds, there were 333 DEGs in the jejunum of starter vs finisher birds suggesting young birds were more sensitive to Met deficiency than older birds. In the liver, Met deficiency activated pathways associated with lipid turnover, amino acid metabolism, oxidative stress, and the immune system, whereas in breast, it activated pathways involved in metabolic regulation, hemostasis, the neuronal system, and oxidative stress, again predicting a negative impact on breast yield. In the starter phase, supplementation with DL-Met compared to MHA-FA inhibited gamma-aminobutyric acid activity and oxidative stress in breast tissue. When data from all tissues were integrated, increased expression of a liver gene (ENSGALG00000042797) was found to be correlated with the expression of several genes that best explained variation due to the Met deficiency in jejunum and breast muscle. Some of these genes were involved in anti-oxidant systems. Overall, the findings indicate that impaired growth performance due to Met deficiency results from an array of tissue-specific molecular mechanisms in which oxidative stress plays a key systemic role. Young birds are more sensitive to Met-deficiency and DL-Met was a preferential source of Met than L- or MHA-FA during the starter phase.

Intestinal inflammation marker calprotectin regulates epithelial intestinal zinc metabolism and proliferation in mouse jejunal organoids.

Calprotectin (CP), a heterodimer of S100A8 and S100A9, is expressed by neutrophils and a number of innate immune cells and is used widely as a marker of inflammation, particularly intestinal inflammation. CP is a ligand for toll-like receptor 4 (TLR4) and the receptor for advanced glycation end products (RAGE). In addition, CP can act as a microbial modulatory agent via a mechanism termed nutritional immunity, depending on metal binding, most notably Zn2+. The effects on the intestinal epithelium are largely unknown. In this study we aimed to characterize the effect of calprotectin on mouse jejunal organoids as a model epithelium, focusing on Zn2+ metabolism and cell proliferation. CP addition upregulated the expression of the Zn2+ absorptive transporter Slc39a4 and of methallothionein Mt1 in a Zn2+-sensitive manner, while downregulating the expression of the Zn2+ exporter Slc30a2 and of methallothionein 2 (Mt2). These effects were greatly attenuated with a CP variant lacking the metal binding capacity. Globally, these observations indicate adaptation to low Zn2+ levels. CP had antiproliferative effects and reduced the expression of proliferative and stemness genes in jejunal organoids, effects that were largely independent of Zn2+ chelation. In addition, CP induced apoptosis modestly and modulated antimicrobial gene expression. CP had no effect on epithelial differentiation. Overall, CP exerts modulatory effects in murine jejunal organoids that are in part related to Zn2+ sequestration and partially reproduced in vivo, supporting the validity of mouse jejunal organoids as a model for mouse epithelium.

Molecular and metabolic responses to immune stress in the jejunum of broiler chickens: transcriptomic and metabolomic analysis.

In the large poultry industry, where farmed chickens are fed at high density, the prevalence of pathogens and repeated vaccinations induce immune stress, which can significantly decrease the production performance and increase the mortality. This study was designed to shed light on the molecular mechanisms and metabolic pathways involved in immune stress through an in-depth analysis of transcriptomic and metabolomic changes in jejunum samples from the broilers. Two groups were established for the experiment: a control group and an LPS group. LPS group received an intraperitoneal injection of LPS solution at a dose of 250 µg per kg at 12, 14, 33, and 35 d of age, whereas the control group received a sterile saline injection. The severity of immune stress was assessed using the Disease Activity Index. A jejunal section was collected to measure the intestinal villus structure (villus length and crypt depth). RNA sequencing and metabolomics data analysis were conducted to reveal differentially expressed genes and metabolites. The results showed that the DAI index was increased and jejunal villus height/crypt depth was decreased in the LPS group. A total of 96 differentially expressed genes and 672 differentially accumulating metabolites were detected in the jejunum by LPS group compared to the control group. The comprehensive analysis of metabolomic and transcriptomic data showed that 23 pathways were enriched in the jejunum and that appetite, nutrient absorption, energy and substance metabolism disorders and ferroptosis play an important role in immune stress in broilers. Our findings provide a deeper understanding of the molecular and metabolic responses in broilers to LPS-induced immune stress, suggesting potential targets for therapeutic strategies to improve the production performance of broiler chickens.

The Significance of Bile in the Biliopancreatic Limb on Metabolic Improvement After Duodenal-Jejunal Bypass.

INTRODUCTION: Duodenal-jejunal bypass (DJB) is an experimental procedure in metabolic surgery that does not have a restrictive component. Changes in bile acid (BA) dynamics and intestinal microbiota are possibly related to metabolic improvement after DJB. Our previous studies involving obese diabetic rats showed the crucial role of the biliopancreatic limb (BPL) in metabolic improvement after DJB caused by BA reabsorption. We established a new DJB procedure to prevent bile from flowing into the BPL and aimed to elucidate the importance of bile in the BPL after DJB. METHODS: Otsuka Long-Evans Tokushima Fatty rats with diabetes were divided into three groups: two DJB groups and a sham group (n = 11). Duodenal-jejunal anastomosis was performed proximal to the papilla of Vater in the DJB group (n = 11). However, the DJB-D group (n = 11) underwent a new procedure with duodenal-jejunal anastomosis distal to the papilla of Vater for preventing bile flow into the BPL. RESULTS: Glucose metabolism improved and weight gain was suppressed in the DJB group, but not in the DJB-D and sham groups. Serum BA level and conjugated BA concentration were elevated in the DJB group. The gut microbiota was altered only in the DJB group; the abundance of Firmicutes and Bacteroidetes decreased and that of Actinobacteria increased. However, the DJB-D group exhibited no apparent change in the gut microbiota, similar to the sham group. CONCLUSION: BAs are essential in the BPL for metabolic improvement after DJB; they can improve the gut microbiota in these processes.

Microbial-transcriptome integrative analysis of heat stress effects on amino acid metabolism and lipid peroxidation in poultry jejunum.

Despite the significant threat of heat stress to livestock animals, only a few studies have considered the potential relationship between broiler chickens and their microbiota. Therefore, this study examined microbial modifications, transcriptional changes and host-microbiome interactions using a predicted metabolome data-based approach to understand the impact of heat stress on poultry. After the analysis, the host functional enrichment analysis revealed that pathways related to lipid and protein metabolism were elevated under heat stress conditions. In contrast, pathways related to the cell cycle were suppressed under normal environmental temperatures. In line with the transcriptome analysis, the microbial analysis results indicate that taxonomic changes affect lipid degradation. Heat stress engendered statistically significant difference in the abundance of 11 microorganisms, including Bacteroides and Peptostreptococcacea. Together, integrative approach analysis suggests that microbiota-induced metabolites affect host fatty acid peroxidation metabolism, which is correlated with the gene families of Acyl-CoA dehydrogenase long chain (ACADL), Acyl-CoA Oxidase (ACOX) and Acetyl-CoA Acyltransferase (ACAA). This integrated approach provides novel insights into heat stress problems and identifies potential biomarkers associated with heat stress.

Conversion of Olmesartan to Olmesartan Medoxomil, A Prodrug that Improves Intestinal Absorption, Confers Substrate Recognition by OATP2B1.

PURPOSE: Olmesartan medoxomil (olmesartan-MX), an ester-type prodrug of the angiotensin II receptor blocker (ARB) olmesartan, is predominantly anionic at intestinal pH. Human organic anion transporting polypeptide 2B1 (OATP2B1) is expressed in the small intestine and is involved in the absorption of various acidic drugs. This study was designed to test the hypothesis that OATP2B1-mediated uptake contributes to the enhanced intestinal absorption of olmesartan-MX, even though olmesartan itself is not a substrate of OATP2B1. METHODS: Tetracycline-inducible human OATP2B1- and rat Oatp2b1-overexpressing HEK 293 cell lines (hOATP2B1/T-REx-293 and rOatp2b1/T-REx-293, respectively) were established to characterize OATP2B1-mediated uptake. Rat jejunal permeability was measured using Ussing chambers. ARBs were quantified by liquid chromatography-tandem mass spectrometry. RESULTS: Significant olmesartan-MX uptake was observed in hOATP2B1/T-REx-293 and rOatp2b1/T-REx-293 cells, whereas olmesartan uptake was undetectable or much lower than olmesartan-MX uptake, respectively. Furthermore, olmesartan-MX exhibited several-fold higher uptake in Caco-2 cells and greater permeability in rat jejunum compared to olmesartan. Olmesartan-MX uptake in hOATP2B1/T-REx-293 cells and in Caco-2 cells was significantly decreased by OATP2B1 substrates/inhibitors such as 1 mM estrone-3-sulfate, 100 µM rifamycin SV, and 100 µM fluvastatin. Rat Oatp2b1-mediated uptake and rat jejunal permeability of olmesartan-MX were significantly decreased by 50 µM naringin, an OATP2B1 inhibitor. Oral administration of olmesartan-MX with 50 µM naringin to rats significantly reduced the area under the plasma concentration-time curve of olmesartan to 76.9%. CONCLUSION: Olmesartan-MX is a substrate for OATP2B1, and the naringin-sensitive transport system contributes to the improved intestinal absorption of olmesartan-MX compared with its parent drug, olmesartan.

Genetic Evidence of Causal Relation Between Intestinal Glucose Absorption and Early Postprandial Glucose Response: A Mendelian Randomization Study.

The postprandial glucose response is an independent risk factor for type 2 diabetes. Observationally, early glucose response after an oral glucose challenge has been linked to intestinal glucose absorption, largely influenced by the expression of sodium-glucose cotransporter 1 (SGLT1). This study uses Mendelian randomization (MR) to estimate the causal effect of intestinal SGLT1 expression on early glucose response. Involving 1,547 subjects with class II/III obesity from the Atlas Biologique de l'Obésité Sévère cohort, the study uses SGLT1 genotyping, oral glucose tolerance tests, and jejunal biopsies to measure SGLT1 expression. A loss-of-function SGLT1 haplotype serves as the instrumental variable, with intestinal SGLT1 expression as the exposure and the change in 30-min postload glycemia from fasting glycemia (Δ30 glucose) as the outcome. Results show that 12.8% of the 1,342 genotyped patients carried the SGLT1 loss-of-function haplotype, associated with a mean Δ30 glucose reduction of -0.41 mmol/L and a significant decrease in intestinal SGLT1 expression. The observational study links a 1-SD decrease in SGLT1 expression to a Δ30 glucose reduction of -0.097 mmol/L. MR analysis parallels these findings, associating a statistically significant reduction in genetically instrumented intestinal SGLT1 expression with a Δ30 glucose decrease of -0.353. In conclusion, the MR analysis provides genetic evidence that reducing intestinal SGLT1 expression causally lowers early postload glucose response. This finding has a potential translational impact on managing early glucose response to prevent or treat type 2 diabetes.

Baicalin ameliorates the gut barrier function and intestinal microbiota of broiler chickens.

The deoxynivalenol (DON)-contaminated feeds can impair chicken gut barrier function, disturb the balance of the intestinal microbiota, decrease chicken growth performance and cause major economic loss. With the aim of investigating the ameliorating effects of baicalin on broiler intestinal barrier damage and gut microbiota dysbiosis induced by DON, a total of 150 Arbor Acres broilers are used in the present study. The morphological damage to the duodenum, jejunum, and ileum caused by DON is reversed by treatment with different doses of baicalin, and the expression of tight junction proteins (ZO-1, claudin-1, and occludin) is also significantly increased in the baicalin-treated groups. Moreover, the disturbance of the intestinal microbiota caused by DON-contaminated feed is altered by baicalin treatment. In particular, compared with those in the DON group, the relative abundances of Lactobacillus, Lachnoclostridium, Ruminiclostridium and other beneficial microbes in the baicalin-treated groups are significantly greater. However, the percentage of unclassified_f__Lachnospiraceae in the baicalin-treated groups is significantly decreased in the DON group. Overall, the current results demonstrate that different doses of baicalin can improve broiler intestinal barrier function and the ameliorating effects on broiler intestinal barrier damage may be related to modulations of the intestinal microbiota.

Epithelial zonation along the mouse and human small intestine defines five discrete metabolic domains.

A key aspect of nutrient absorption is the exquisite division of labour across the length of the small intestine, with individual nutrients taken up at different proximal:distal positions. For millennia, the small intestine was thought to comprise three segments with indefinite borders: the duodenum, jejunum and ileum. By examining the fine-scale longitudinal transcriptional patterns that span the mouse and human small intestine, we instead identified five domains of nutrient absorption that mount distinct responses to dietary changes, and three regional stem cell populations. Molecular domain identity can be detected with machine learning, which provides a systematic method to computationally identify intestinal domains in mice. We generated a predictive model of transcriptional control of domain identity and validated the roles of Ppar-δ and Cdx1 in patterning lipid metabolism-associated genes. These findings represent a foundational framework for the zonation of absorption across the mammalian small intestine.

Environmentally realistic dose of tire-derived metabolite 6PPD-Q exposure causes intestinal jejunum and ileum damage in mice via cannabinoid receptor-activated inflammation.

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6PPD-Q) is a quinone derivative of a common tire additive 6PPD, whose occurrence has been widely reported both in the environment and human bodies including in adults, pregnant women and children. Yet, knowledge on the potential intestinal toxicity of 6PPD-Q in mammals at environmentally relevant dose remain unknown. In this study, the effects of 6PPD-Q on the intestines of adult ICR mice were evaluated by orally administering environmentally relevant dose or lower levels of 6PPD-Q (0.1, 1, 10, and 100 µg/kg) for 21 days. We found that 6PPD-Q disrupted the integrity of the intestinal barrier, mostly in the jejunum and ileum, but not in the duodenum or colon, in a dose-dependent manner. Moreover, intestinal inflammation manifested with elevated levels of TNF-α, IL-1, and IL-6 mostly observed in doses at 10 and 100 µg/kg. Using reverse target screening technology combining molecular dynamic simulation modeling we identified key cannabinoid receptors including CNR2 activation to be potentially mediating the intestinal inflammation induced by 6PPD-Q. In summary, this study provides novel insights into the toxic effects of emerging contaminant 6PPD-Q on mammalian intestines and that the chemical may be a cannabinoid receptor agonist to modulate inflammation.

Comparative Intra-Subject Analysis of Gene Expression and Protein Abundance of Major and Minor Drug Metabolizing Enzymes in Healthy Human Jejunum and Liver.

First pass metabolism by phase I and phase II enzymes in the intestines and liver is a major determinant of the oral bioavailability of many drugs. Several studies analyzed expressions of major drug-metabolizing enzymes (DMEs), such as CYP3A4 and UGT1A1 in the human gut and liver. However, there is still a lack of knowledge regarding other DMEs (i.e., "minor" DMEs), although several clinically relevant drugs are affected by those enzymes. Moreover, there is very limited intra-subject data on hepatic and intestinal expression levels of minor DMEs. To fill this gap of knowledge, we analyzed gene expression (quantitative real-time polymerase chain reaction) and protein abundance (targeted proteomics) of 24 clinically relevant DMEs, that is, carboxylesterases (CES), UDP-glucuronosyltransferases (UGT), and cytochrome P450 (CYP)-enzymes. We performed our analysis using jejunum and liver tissue specimens from the same 11 healthy organ donors (8 men and 3 women, aged 19-60 years). Protein amounts of all investigated DMEs, with the exception of CYP4A11, were detected in human liver samples. CES2, CYP2C18, CYP3A4, and UGT2B17 protein abundance was similar or even higher in the jejunum, and all other DMEs were found in higher amounts in the liver. Significant correlations between gene expression and protein levels were observed only for 2 of 15 jejunal, but 13 of 23 hepatic DMEs. Intestinal and hepatic protein amounts only significantly correlated for CYP3A4 and UGT1A3. Our results demonstrated a notable variability between the individuals, which was even higher in the intestines than in the liver. Our intrasubject analysis of DMEs in the jejunum and liver from healthy donors, may be useful for physiologically-based pharmacokinetic-based modeling and prediction in order to improve efficacy and safety of oral drug therapy.

Resveratrol alleviates heat-stress-induced impairment of the jejunal mucosa through TLR4/MAPK signaling pathway in black-boned chicken.

Heat stress in chickens caused by high temperatures in summer is a serious issue faced by the poultry industry globally, which reduces product quality. The aim of this study is to investigate the role of resveratrol in alleviating heat stress injury and inflammatory response of jejunal mucosa in black-boned chickens through TLR4/MAPK signaling pathway. In total, 240 black-boned chickens (28-day old) were randomly divided into 4 treatment groups as follows. The normal temperature (NT) and normal temperature with resveratrol (NT+Res) groups received a basal diet without and with 400 mg/kg resveratrol, respectively, and treated at 24℃ ± 2℃, 24 h/d. The high temperature (HT) and high temperature with resveratrol (HT+Res) groups received basal diet without and with 400 mg/kg resveratrol, respectively, and treated at 37℃ ± 2℃ for 8 h/d and 24°C ± 2°C for the rest of the time for 12 d. The results revealed the heat-stress responses impaired the villous structure of the jejunum, causing a rough and uneven surface of the jejunal villus, and local intestinal villi were even more prone to rupture. However, resveratrol significantly improved the morphology and structure of jejunal mucosa under heat stress. Heat stress increased the mRNA levels of toll-like receptor 4 (TLR4), c-Jun, c-fos, caspase-3, and p38 (P < 0.05), reduced mRNA level of Bcl-2, and reduced the expression of tight junction proteins Occludin, ZO-1, and Claudin1 (P < 0.05) in the jejunal mucosa. However, resveratrol inhibited the TLR4/ mitogen-activated protein kinase (MAPK) signaling pathway via downregulating TLR4, c-Jun, p38, and caspase-3 (P < 0.05); upregulating Bcl-2 (P < 0.05); decreasing the protein levels of MKK3, p53, and myeloid differentiation factor 88 (MYD88); and increasing the protein levels of Occludin, ZO-1, and Claudin1. In addition, it reduced the levels of JNK and p38 proteins (P < 0.05) and inflammatory factors like tumor necrosis factor-α (TNF-α) in the jejunal mucosa of black-boned chickens under heat stress. In conclusion, resveratrol may play a regulatory role in heat-stress-induced damage and inflammatory response in the intestinal mucosa of black-boned chickens under heat stress.

Gastrointestinal stromal tumour in a jejunal diverticulum: The eighth reported case worldwide with a brief review of the literature.

Jejunal diverticulosis is uncommon and so are gastrointestinal stromal tumours (GIST) arising in the jejunum. GIST arising in a jejunal diverticulum is a rarity and to date there are only 7 cases in the English literature. Our case of GIST occurring in a jejunal diverticulum of a 48-year-old lady would be the first reported in Malaysia and the 8th in the world. As in most cases, the clinical presentation and radiological findings of this patient were non-specific. With a history of acute abdominal pain, vomiting and fever, the patient was provisionally diagnosed as a case of twisted ovarian cyst and subjected to laparotomy. An intact roundish jejunal diverticulum 5.0 cm x 5.0 cm, about 50 cm distal to the duodeno-jejunal junction was found and resected with a segment of small intestine. Microscopic examination showed a tumour of the cut open diverticular wall, with epithelioid to spindled cells, demonstrating a mitotic rate of 1-2 per 5 mm2, confined to, while infiltrating the wall of the diverticulum. The immunohistochemical profile of positive staining for CD117, DOG-1, smooth muscle actin and CD34, and negative expression of desmin and S100 protein, clinched the diagnosis of GIST. Based on the AFIP Criteria for risk stratification,1 the patient was categorised as having moderate risk for disease progression, and was not offered further targeted imatinib as an immediate measure. The patient has remained well at the time of writing i.e. 8 months following excision, and continues on active surveillance by the surgical and oncological teams, with the option of imatinib, should the necessity arise. This case is presented not merely for the sake of documenting its rarity, but as a reminder to stay alert for uncommon conditions in histopathology practice.

Methionine sources at different dietary levels alters the growth and expression of genes related to homocysteine remethylation in the jejunum of broilers.

Sulfur amino acids are essential for the proper development of broilers and are required throughout the bird's life to perform important physiological functions. Studies that seek to understand the actions of sulfur amino acids in the body of birds are essential. The present study evaluated the influence of sulfur amino acid supplementation using DL-Methionine (DL-Met) and DL-Methionine hydroxy analogue (DL-HMTBA), on the performance and expression of genes related to methionine metabolism, in the jejunum of broilers. Four hundred and fifty male broilers (Cobb-700 slow feathering) were distributed in a completely randomized design, in a factorial scheme (2x3), with two sources of methionine (DL-Met and DL-HMTBA) and three levels of methionine (deficiency, requirement and excess). The mRNA expression of the MAT1, MTR, BHMT, MTRR, CBG and GSS genes, and performance data such as feed intake, weight gain, and feed conversion were evaluated. DL-HMTBA increased the expression of BHMT (p = 0.0072) and MTRR (p = 0.0003) in the jejunum of the birds. Methionine deficiency increased the expression of BHMT (p = 0.0805) and MTRR (p = 0.0018). Higher expression of GSS was observed in birds that were supplemented with DL-HMTBA (p = 0.0672). Analyzing our results, it is preferable to supplement sulfur amino acids with DL-Met at the requirement level. Birds fed with DL-HMTBA showed worse weight gain (p = 0.0117) and higher feed conversion (p = 0.0170); methionine deficiency resulted in higher feed intake (p = 0.0214), lower weight gain (p<0.0001) and consequently higher feed conversion (p<0.0001). Based on the information found in this work, it is recommended to supplement sulfur amino acids with DL-Met at the level of compliance with the requirement.

Aster-dependent nonvesicular transport facilitates dietary cholesterol uptake.

Intestinal absorption is an important contributor to systemic cholesterol homeostasis. Niemann-Pick C1 Like 1 (NPC1L1) assists in the initial step of dietary cholesterol uptake, but how cholesterol moves downstream of NPC1L1 is unknown. We show that Aster-B and Aster-C are critical for nonvesicular cholesterol movement in enterocytes. Loss of NPC1L1 diminishes accessible plasma membrane (PM) cholesterol and abolishes Aster recruitment to the intestinal brush border. Enterocytes lacking Asters accumulate PM cholesterol and show endoplasmic reticulum cholesterol depletion. Aster-deficient mice have impaired cholesterol absorption and are protected against diet-induced hypercholesterolemia. Finally, the Aster pathway can be targeted with a small-molecule inhibitor to manipulate cholesterol uptake. These findings identify the Aster pathway as a physiologically important and pharmacologically tractable node in dietary lipid absorption.

Smooth Muscle Actin as a Criterion for Gravisensitivity of Stomach and Jejunum in Laboratory Rodents.

Smooth muscle tissue (SMT) is one of the main structural components of visceral organs, acting as a key factor in the development of adaptive and pathological conditions. Despite the crucial part of SMT in the gastrointestinal tract activity, the mechanisms of its gravisensitivity are still insufficiently studied. The study evaluated the content of smooth muscle actin (α-SMA) in the membranes of the gastric fundus and jejunum in C57BL/6N mice (30-day space flight), in Mongolian gerbils Meriones unguiculatus (12-day orbital flight) and after anti-orthostatic suspension according to E.R. Morey-Holton. A morphometric analysis of α-SMA in the muscularis externa of the stomach and jejunum of mice and Mongolian gerbils from space flight groups revealed a decreased area of the immunopositive regions, a fact indicating a weakening of the SMT functional activity. Gravisensitivity of the contractile structures of the digestive system may be due to changes in the myofilament structural components of the smooth myocytes or myofibroblast actin. A simulated antiorthostatic suspension revealed no significant changes in the content of the α-SMA expression level, a fact supporting an alteration in the functional properties of the muscularis externa of the digestive hollow organs under weightless environment. The data obtained contribute to the novel mechanisms of the SMT contractile apparatus remodeling during orbital flights and can be used to improve preventive measures in space biomedicine.