Intestinal Mucosa Research Articles

The Consumption of the Fibrous Fraction of Solanum lycocarpum St. Hil. Does Not Preserve the Intestinal Mucosa in TNBS-Induced Rats.

Solanum lycocarpum St. Hil. is considered a natural anti-inflammatory. In traditional medicine, it is used to reduce cholesterol levels in the treatment of obesity. Foods capable of conferring a protective and nutritious effect have been used to prevent or attenuate the clinical symptoms of inflammatory bowel diseases. Ulcerative colitis is a multifactorial inflammatory bowel disease. This study investigated the impact of the consumption of the fibrous fraction (FF) and resistant starch (RS) of fruta-do-lobo in an experimental model of colitis induced with the use 2,4,6-trinitrobenzene sulphonic acid (TNBS) in rats. The different colitis groups all experienced decreased weight gain, which could be linked to the inflammatory process (p = 0.603). Additionally, the experimental model led to increased oxidative stress, higher levels of pro-inflammatory cytokines, and the elevated gene expression of these cytokines. Despite this, consuming the fibrous fraction of fruta-do-lobo (RS and FF) did not appear to protect the animals against the inflammatory process. Regarding the expression of TNF-α, only the group treated with the drug mesalamine had a reduced serum level of this inflammatory marker (p = 0.03). Our results showed that the diet containing RS and FF did not protect the intestinal mucosa against TNBS inflammation. New studies on the variation in the time of consumption or the supplemented dose of fruta-do-lobo fibers could help to elucidate their effects in protecting the mucosa.

A lymphocyte chemoaffinity axis for lung, non-intestinal mucosae and CNS.

Tissue-selective chemoattractants direct lymphocytes to epithelial surfaces to establish local immune environments, regulate immune responses to food antigens and commensal organisms, and protect from pathogens. Homeostatic chemoattractants for small intestines, colon, and skin are known1 2, but chemotropic mechanisms selective for respiratory tract and other non-intestinal mucosal tissues (NIMT) remain poorly understood. Here we leveraged diverse omics datasets to identify GPR25 as a lymphocyte receptor for CXCL17, a chemoattractant cytokine whose expression by epithelial cells of airways, upper gastrointestinal and squamous mucosae unifies the NIMT and distinguishes them from intestinal mucosae. Single-cell transcriptomic analyses show that GPR25 is induced on innate lymphocytes prior to emigration to the periphery, and is imprinted in secondary lymphoid tissues on activated B and T cells responding to immune challenge. GPR25 characterizes B and T tissue resident memory and regulatory T lymphocytes in NIMT and lungs in humans and mediates lymphocyte homing to barrier epithelia of the airways, oral cavity, stomach, biliary and genitourinary tracts in mouse models. GPR25 is also expressed by T cells in cerebrospinal fluid and CXCL17 by neurons, suggesting a role in CNS immune regulation. We reveal widespread imprinting of GPR25 on regulatory T cells, suggesting a mechanistic link to population genetic evidence that GPR25 is protective in autoimmunity3,4. Our results define a GPR25-CXCL17 chemoaffinity axis with the potential to integrate immunity and tolerance at non-intestinal mucosae and the CNS.

Influence of different types of dietary sugars on the intestinal mucosa and hepatic lipid metabolism in germ-free mice

The excessive consumption of dietary sugar induces changes in gut microbiota, which is associated with obesity and metabolic dysregulation. This study investigated the effects of monosaccharide and fructooligosaccharide (FOS) intake on metabolic function and intestinal environment in germ-free (GF) mice lacking gut microbiota. GF mice were provided with a chow diet and administered a water solution containing 15 % glucose, fructose, or FOS for 4 weeks. Compared with FOS, glucose, and fructose induced increased hepatic lipid accumulation, increased adipocyte size in white adipose tissue, and upregulated hepatic lipogenic gene expression. FOS exhibited notably higher activation of hepatic AMP-activated protein kinase compared with those consuming glucose or fructose. Moreover, the number of goblet cells in the intestinal mucosa increased significantly with FOS consumption. Collectively, these findings indicate that while monosaccharides caused metabolic disorders in GF mice, FOS alleviated these disorders and increased the number of goblet cells in the intestinal mucosa. These results provide evidence for the occurrence of these effects independently of the gut microbiota.

Vitamin D and Bone Metabolism in Celiac Disease. The Possibilities of Dietary Correction

The review describes the state of the vitamin D system and bone metabolism in celiac disease, the mechanisms of the influence of vitamin D on the state of the intestinal mucosa, and risk factors that contribute to pathological changes in bones in celiac disease. Studies are presented that evaluate bone mineral density, bone metabolism, and vitamin D status in patients with celiac disease. The results of a discussion on the effect of calcium and vitamin D supplements on the course of celiac disease and the condition of bone tissue in this disease are presented.

Claudin is a promising biomarker of intestinal wall permeability

To date, sufficient information is available on changes in the levels of tight contact proteins (TCPs) in various diseases. Of greatest interest is the study of claudin due to numerous studies confirming the important role of this protein in the development of pathologies. Deafness, behavioural changes, and nerve conduction disorders occur due to insufficient claudin production. Claudin is involved in the maintenance of cell polarity due to its apical location in the cell. When pathological processes occur, claudin may undergo phosphorylation, leading to changes in cell polarity and impaired regulation of APC levels. Irritable bowel syndrome is one of the possible causes of impaired regulation of claudin levels. In this pathology there is adecrease in claudin-1 expression. In addition, claudins play different roles in different tumour tissues, and the same protein may be differentially expressed in different forms of cancer. Claudin-4 expression is upregulated as disease progresses in colorectal cancer (CRC), oesophageal squamous cell carcinoma, and its upregulation is associated with decreased invasiveness and metastatic potential, which is positively correlated with improved prognosis. In contrast, overexpression of CLDN 4 in breast cancer (BC) and pancreatic cancer (PC) is positively correlated with invasion, metastasis, angiogenesis and poor prognosis. Aim: systematisation of available data on the biological role and clinical significance of claudin. Materials: review of Russian and foreign literature from 2013-2023.

Intestinal fatty acid-binding protein (I-FABP) as biomarker of ischemic damage in experimentally induced 12-h small bowel obstruction.

Laboratory tests have low diagnostic specificity for strangulated intestinal obstruction. The diagnostic potential of the intestinal fatty acid-binding protein (I-FABP) expressed in the tips of the intestinal villi continues to be explored. The number of white blood cells, blood plasma levels of L-lactate, C-reactive protein (CRP) and I-FABP were measured in rats with experimentally induced 12-h strangulated and non-strangulated intestinal obstruction. The results of the laboratory tests were compared with the changes in the morphology of the intestinal wall. The studied diagnostic markers, except for CRP, were elevated by 12-h L-lactate and I-FABP concentrations were significantly higher in the strangulated obstruction group than in other groups. L-lactate (cutoff value: 3.01mmol/L) had 86.1% sensitivity and 66.7% specificity for strangulated obstruction (AUC 0.815, p < 0.001). I-FABP levels above 5.432ng/ml indicated strangulated obstruction with 83.33% sensitivity and 88.9% specificity (AUC 0.906, p < 0.001). Villi destruction was observed at 2h in the strangulated obstruction group. I-FABP levels peaked at 4h and plateaued at 12h. Functional changes were observed in the non-strangulated group; they were accompanied by a significant increase in I-FABP concentrations that lasted until 12h. Compared with traditional diagnostic markers of strangulated intestinal obstruction, I-FABP demonstrated higher accuracy in the first 12h, although its concentrations reached the plateau already at 4h and did not increase thereafter. The functional changes in small bowel wall in non-strangulated obstruction were accompanied by continuous increase in I-FABP concentrations up to 12h, which may have influenced the diagnostic accuracy of the marker.

46 Feeding the weaned pig gut and beyond with non-nutritional additives

Abstract Weaning imposes simultaneous stress, resulting in reduced growth performance, increased susceptibility to diseases, and increased morbidity and mortality in weaned pigs. Weaning stress can induce negative changes in the intestine, including damaged intestinal integrity, disturbed digestive and absorptive capacity, increased intestinal oxidative stress, and microbial dysbiosis. Improving intestinal development and health is critically important for enhancing disease resistance and overall health of weaned pigs. This, in turn, can increase their survival rate during this vulnerable stage and improve their productive performance in later stages. A healthy gut may include, but is not limited to, several important features: a healthy proliferation of intestinal epithelial cells, an integrated gut barrier function, a preferable or balanced gut microbiota, and well-developed intestinal mucosa immunity. Burgeoning evidence suggests that many non-nutritional additives can enhance overall intestinal health and beyond by targeting one or several functions of the gut. However, the exact protective mechanisms may vary and are still not completely understood. For example, direct-fed microbials may confer health benefits on the host by producing antimicrobial products, regulating gut microbial profile or immunity, and/or enhancing gut barrier function. Non-digestible carbohydrates and prebiotics exhibit striking impacts on reshaping the composition of gut microbiota in the host by boosting the production of health-promoting bacteria. Phytochemicals, a large variety of secondary plant metabolites, have been known for their broad and promising biological properties, including anti-microbial, antioxidant, and immune-modulating activities. Several short chain fatty acids derivatives aim to target the upper gastrointestinal tract, where the major nutrients are digested and absorbed, to promote intestinal health of pigs. Moreover, butyrate and valerate glycerides exhibit strong in vitro antimicrobial effects against enterotoxigenic Escherichia coli F18, one of the dominant pathogens causing post-weaning diarrhea globally. There are more candidates in the list that have been used in weaned pigs and shown promising results on growth and health promotion. Therefore, increasing our current understanding of non-nutritional additives and their influences on intestinal function during weaning will facilitate the development of more dietary strategies that increase stress resilience of weaned pigs.

Intestinal fatty acid binding protein is associated with infarct size and cardiac function in acute heart failure following myocardial infarction

BackgroundIn acute heart failure (HF), reduced cardiac output, vasoconstriction and congestion may damage the intestinal mucosa and disrupt its barrier function. This could facilitate the leakage of bacterial products into...

Use of Oral Gentamicin in Children with Primary Immunodeficiency and Recurrent Campylobacter coli Bacteremia: A Case Report

Immunosuppressed patients are more at risk of suffering bacteremias due to atypical microorganisms such as Campylobacter coli, which can colonize their intestinal mucosa due to the absence of IgA, the main immunoglobulin of the mucosa and which is not provided with intravenous or subcutaneous immunoglobulin treatment. We have recently had a case of a 5-year-old girl with autosomal recessive agammaglobulinemia with recurrent Campylobacter coli bacteremia and positive stool cultures for the same microorganism. She was treated with intravenous antibiotherapy and given the recurrence of bacteremia, oral gentamicin was associated with this treatment to try to achieve intestinal eradication of the germ. Oral gentamicin was well tolerated, gave no side effects, and managed to eradicate the microorganism 6 months after the end of treatment. We want to reflect the scarce literature on the use of oral gentamicin, the dose and duration of treatment, and the good evolution of our patient with the regimen used.

48 Dietary functional fiber properties for improved health and disease outcomes in pigs

Abstract In swine production, using feed antibiotics as antimicrobial growth promotants has been reduced; thus, feed alternatives to manage gut health are required. Dietary fiber and similar carbohydrate structures such as resistant starch, oligosaccharides, and exopolysaccharides are nutritional tools that may enhance gut health in pigs. Dietary fiber may have a role to alleviate diarrheal diseases including in pigs post-weaning but can also reduce constipation in sows, but specific functionality depends on fiber properties. Antibiotics are hypothesized to influence gut health via modulation of intestinal microbial profiles; fermentation and intestinal inflammation are considered important mechanisms. Dietary fiber sources differ in a key functional property: fermentability. Rapid fermentation of fiber and oligosaccharides is associated with changes in microbial profiles and increased metabolite production. Recently, microbial composition was hypothesized to be less important and combined output of metabolites should be the focus. Fiber properties may also manipulate retention time and physico-chemical properties of the undigested residue; hence, non-fermentable fiber may prevent constipation in sows. The fiber-like structure resistant starch is not digested and acts as fermentable fiber but has unique properties, because it specifically increases intestinal abundance of bifidobacteria, which are associated with improved gut health. Using crop breeding, feed processing, and feed additives, the structure of fiber and starch can be altered thereby changing its degradation kinetics and affecting its prebiotic activity. Finally, fiber-like structures such as exopolysaccharides from Limosilactobacillus reuteri and unique oligosaccharides may serve as receptor analogues for pathogenic bacteria, e.g., enterotoxigenic Escherichia coli (ETEC). These receptor analogues block lectin domains of bacterial adhesins and thus prevent adherence of pathogens to the gut wall, thereby avoiding initiation of post-weaning diarrhea. In conclusion, dietary fiber and similar structures possess important functional properties that may also provide important solutions to maintain gut health in pigs.

Correlating Ultrastructural Changes in the Invasion Area of Colorectal Cancer with CT and MRI Imaging.

The cancer invasion of the large intestine, a destructive process that begins within the mucous membrane, causes cancer cells to gradually erode specific layers of the intestinal wall. The normal tissues of the intestine are progressively replaced by a tumour mass, leading to the impairment of the large intestine's proper morphology and function. At the ultrastructural level, the disintegration of the extracellular matrix (ECM) by cancer cells triggers the activation of inflammatory cells (macrophages) and connective tissue cells (myofibroblasts) in this area. This accumulation and the functional interactions between these cells form the tumour microenvironment (TM). The constant modulation of cancer cells and cancer-associated fibroblasts (CAFs) creates a specific milieu akin to non-healing wounds, which induces colon cancer cell proliferation and promotes their survival. This review focuses on the processes occurring at the "front of cancer invasion", with a particular focus on the role of the desmoplastic reaction in neoplasm development. It then correlates the findings from the microscopic observation of the cancer's ultrastructure with the potential of modern radiological imaging, such as computer tomography (CT) and magnetic resonance imaging (MRI), which visualizes the tumour, its boundaries, and the tissue reactions in the large intestine.

Ex vivo electrical bioimpedance measurements and Cole modelling on the porcine colon and rectum

Different pathological changes in the large intestine wall, associated with the development of different chronic diseases, including colorectal cancer, could be reflected in electrical bioimpedance readings. Thickness and composition of the mucus bilayer covering it in the luminal side, abundance of bacteria of the intestinal microbiota, the permeability of the epithelium and inflammation are some of these. However, scientific literature on electrical passive properties of the large intestine is scarce. In this study, complex impedance measurements at 8 frequencies were carried out on 6 specimens of porcine colorectal tissue, within half ab hour post-mortem, obtained from a local abattoir. For 5 different distances, measured proximally from the border of the anus, 3 readings were taken at 3 different points with a tetrapolar probe. The results show 2 different dielectric dispersions in the α and β regions and it seems that there is a relationship between the values of resistivities and the thickness of the wall. Also, parameter values both for the Cole and the geometrical models are given. Another set of electrical bioimpedance readings was carried out in order to assess the effect of the mucus layer on electrical properties of the tissue. It seems that these layers are related to the low frequency dispersion. Finally, electrical passive properties of porcine colorectal tissue, reported in this work, give reference values and behaviour patterns that could be applied for further research in human medicine, based on bioimpedance measurements.

Prokinetic effect of erythromycin in the management of gastroparesis in critically ill patients-our experience and literature review.

Gastroparesis is a disorder characterized by impaired gastric emptying and the accumulation of food in the intestines without any clear mechanical cause. Gastroparesis in critical care patients is a prevalent issue in the intensive care unit. The disruption of normal gastrointestinal motility in critically ill patients is linked to a significant risk of intolerance to enteral feeding, colonization of the gastrointestinal tract with pathogenic bacterial strains, increased permeability of the intestinal wall, translocation of the intestinal microbiota, leading to progressive malnutrition, and potential development of bacterial infection. The literature was reviewed to assess the benefits and risks associated with the use of this medication. The aim of the study was to treat the symptoms of gastroparesis and stimulate gastrointestinal motility. Consequently, the aim was to reduce the amount of backed-up food content in the stomach, accelerate gastrointestinal motility, and return to intestinal feeding. Gastroparesis is a frequent issue among patients in the intensive care unit. Critical illness can lead to gastrointestinal motility disorders, causing slowed gastric emptying. This increases the risk of problems such as intolerance to enteral feeding, regurgitation, and aspiration of gastrointestinal contents into the respiratory tract, as well as colonization of the gastrointestinal tract by pathogens. Over time, impaired intestinal absorption can result in malnutrition, necessitating the initiation of parenteral nutrition. After analysis of the literature and published scientific reports, as well as considering their own research, it is evident that erythromycin, as a prokinetic drug, effectively enhances gastrointestinal motility. This contributes to stimulating gastric emptying in critically ill patients with gastroparesis who are hospitalized in an intensive care unit. The use of erythromycin in combination with metoclopramide and/or itopride hydrochloride allows for a synergistic effect, leading to the quickest possible return to enteral feeding.

Knowledge and Attitude of Celiac Disease Among the Population of Riyadh, Saudi Arabia.

Background and aims Celiac disease (CD) is a chronic autoimmune disease that is characterized by inflammation of the intestinal mucosa, primarily triggered by gluten. So far, the effective management of CD only includes a gluten-free diet. For early diagnosis and management, adequate knowledge and a positive attitude towards CD are crucial. This study aims to investigate the CD-related knowledge and attitudes of the public in Riyadh, Saudi Arabia. Methods A cross-sectional online survey was conducted among individuals aged 16 and older. The data regarding demographic factors, knowledge, and attitudes about CD was collected via an online questionnaire. Statistical analysis was conducted using version 26 of SPSS(IBM Corp., Armonk, NY). Results In the current study, 669 individuals responded to the online survey. The majority of participants (82.1%) were familiar with CD. A total of 59.9% of respondents had adequate knowledge, 32.3% had outstanding knowledge, and 7.8% reported no knowledge of CD. The majority (69.5%) of respondents held negative attitudes concerning CD. The correlation between age and CD knowledge (P<0.05) and attitude (P<0.05) was statistically significant. Similarly, the correlation between occupation and CD knowledge (P<0.05) and attitude (P<0.05) was statistically significant. However, no significant association between gender and CD knowledge (p=0.720) or attitude (p=0.244) was found in males and females. Conclusion This study revealed that the majority of the residents of Riyadh, Saudi Arabia, had an adequate or excellent understanding of CD. However, the majority of respondents had a negative attitude towards CD management.

Role of the serosa in intestinal anastomotic healing: insights from in-depth histological analysis of human and murine anastomoses.

Anastomotic leakage following colorectal surgery remains a significant complication despite advances in surgical techniques. Recent findings on serosal injury repair in coelomic cavities, such as the peritoneum, challenge the current understanding of the cellular origins and mechanisms underlying intestinal anastomotic healing. Understanding the contribution of each layer of the intestinal wall during anastomotic healing is needed to find new therapeutic strategies to prevent anastomotic leakage. The aim of this experimental study was to investigate the role of the serosal layer of the intestinal wall in anastomotic healing. Comprehensive histologic analysis of human and murine anastomoses was performed to elucidate histologic changes in the different intestinal layers during anastomotic healing. In vivo staining of the extracellular matrix (ECM) in the serosal layer was performed using a fluorophore-conjugated N-hydroxysuccinimide-ester before anastomosis surgery in a murine model. Histological examination of both human and murine anastomoses revealed that closure of the serosal layer occurred first during the healing process. In vivo serosal ECM staining demonstrated that a significant portion of the newly formed ECM within the anastomosis was indeed deposited onto the serosal layer. Furthermore, mesenchymal cells within the anastomotic scar were positive for mesothelial cell markers, podoplanin and Wilms tumour protein. In this experimental study, the results suggest that serosal scar formation is an important mechanism for anastomotic integrity in intestinal anastomoses. Mesothelial cells may significantly contribute to scar formation during anastomotic healing through epithelial-to-mesenchymal transition, potentially suggesting a novel therapeutic target to prevent anastomotic leakage by enhancing physiological healing processes.

The effect of vitamin D3 and omega-3 combination, taken orally, on triglycerides, lining of intestine, and the biodiversity of gut microbiota in healthy rats.

The gut microbiota plays a key role in host health. An intake of omega-3 and vitamin D3 in a separate manner is vital for maintaining good health of gut microbiota and controlling some illness manifestations. The aim of this study is to investigate the potential change in biodiversity of the gut microbiome in healthy rats supplemented with vitamin D3, omega-3 alone and their combination and to reflect onto the triglyceride levels in serum and fecal samples. Using the 16S rRNA gene Miseq Illumina NGS, and monitoring triglyceride levels in serum and fecal samples coupled with several clinical parameters, we examined the effect of orally taken combination of omega-3 and vitamin D3 alongside the separate intake of supplements on gut microbiota in 24 healthy white Wistar rats for six weeks. The study findings showed that combination treatment encouraged the growth of opportunistic Clostridia class during day 21 and 42 of treatment by 7.7 and 7.4 folds, respectively, exhibited incomplete absorption levels for both supplements when used concomitantly, demonstrated a damaging effect on the gut intestinal lining wall thickness (126 µm) when compared to control group (158 µm), increasing lumen diameter (400 µm), and showed higher triglyceride level in fecal samples. These findings indicate that omega-3 and vitamin D3 supplements as combination intake reveal unfavorable effects, thus, it is advised to conduct further in-depth studies to clarify the presence or absence of any chemical interaction between both supplements' molecules and to investigate based on human model to attain a superior perspective.

Unlocking the power of short-chain fatty acids in ameliorating intestinal mucosal immunity: a new porcine nutritional approach.

Short-chain fatty acids (SCFAs), a subset of organic fatty acids with carbon chains ranging from one to six atoms in length, encompass acetate, propionate, and butyrate. These compounds are the endproducts of dietary fiber fermentation, primarily catalyzed by the glycolysis and pentose phosphate pathways within the gut microbiota. SCFAs act as pivotal energy substrates and signaling molecules in the realm of animal nutrition, exerting a profound influence on the intestinal, immune system, and intestinal barrier functions. Specifically, they contibute to 60-70% of the total energy requirements in ruminants and 10-25% in monogastric animals. SCFAs have demonstrated the capability to effectively modulate intestinal pH, optimize the absorption of mineral elements, and impede pathogen invasion. Moreover, they enhance the expression of proteins associated with intestinal tight junctions and stimulate mucus production, thereby refining intestinal tissue morphology and preserving the integrity of the intestinal structure. Notably, SCFAs also exert anti-inflammatory properties, mitigating inflammation within the intestinal epithelium and strengthening the intestinal barrier's defensive capabilities. The present review endeavors to synthesize recent findings regarding the role of SCFAs as crucial signaling intermediaries between the metabolic activities of gut microbiota and the status of porcine cells. It also provides a comprehensive overview of the current literature on SCFAs' impact on immune responses within the porcine intestinal mucosa.

Immune-mediated impairment of tonic immobility defensive behavior in an experimental model of colonic inflammation.

Ulcerative colitis has been associated with psychological distress and an aberrant immune response. The immunomodulatory role of systemic cytokines produced during experimental intestinal inflammation in tonic immobility (TI) defensive behavior remains unknown. The present study characterized the TI defensive behavior of guinea pigs subjected to colitis induction at the acute stage and after recovery from intestinal mucosa injury. Moreover, we investigated whether inflammatory mediators (tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-8, IL-10, and prostaglandins) act on the mesencephalic nucleus, periaqueductal gray matter (PAG). Colitis was induced in guinea pigs by intrarectal administration of acetic acid. The TI defensive behavior, histology, cytokine production, and expression of c-FOS, IBA-1, and cyclooxygenase (COX)-2 in PAG were evaluated. Colitis reduced the duration of TI episodes from the first day, persisting throughout the 7-day experimental period. Neuronal c-FOS immunoreactivity was augmented in both columns of the PAG (ventrolateral (vlPAG) and dorsal), but there were no changes in IBA-1 expression. Dexamethasone, infliximab, and parecoxib treatments increased the duration of TI episodes, suggesting a modulatory role of peripheral inflammatory mediators in this behavior. Immunoneutralization of TNF-α, IL-1β, and IL-8 in the vlPAG reversed all effects produced by colitis. In contrast, IL-10 neutralization further reduced the duration of TI episodes. Our results reveal that peripherally produced inflammatory mediators during colitis may modulate neuronal functioning in mesencephalic structures such as vlPAG.

Abstract 02: Time restricted feeding reduces kidney fibrosis in diet-induced obesity through limiting kidney CD8+ T cell infiltration

Obesity is a leading cause of chronic kidney disease (CKD). Our lab previously showed that a 20 week diet-induced obesity (DIO) protocol (45% high fat) significantly increased kidney medullary fibrosis in male mice. Further, we found that time restricted feeding (TRF, feeding during 12-hr dark phase only) during the final 2 weeks of the 20-week DIO protocol significantly reduced kidney fibrosis. DIO mice showed significantly greater CD8+ T cells, compared to mice on a normal diet (ND) only during the dark phase. TRF in the DIO mice normalized the CD8+ T cell to that similar to ND mice. We hypothesized that pro-fibrotic CD8+ T cells infiltrate the kidney and mediate damage in the DIO mice. We used anti (a)-CD8 treatment during the final 2 weeks of DIO to deplete all CD8+ T cells. Separate cohorts of ND and DIO mice received control a-IgG treatment during the final 2 weeks of the protocol. DIO mice treated with a-CD8 showed significantly reduced kidney fibrosis compared to DIO mice treated with a-IgG and similar to ND mice treated with a-IgG (assessed by blue trichrome and picrosirius red staining; one-way ANOVA, p=0.018; NDa-IgG vs DIOa-IgG: p=0.033; DIOa-IgG vs DIOa-CD8: p=0.032). We next investigated the intestinal mucosa (IM) as a source of the kidney-infiltrating CD8+ T cells in DIO mice since the IM is one of the primary non-lymphoid sites of T cells in the body. Previous studies have shown that migration of T cells from the IM to the kidney can drive acute kidney injury, but it is unclear if this occurs with chronic models such as DIO. We used the KikumeGreen (KikGr) mouse model to identify migrating cells into the kidney. When KikGR protein is exposed to 408 nm blue light it is photoconverted to a KikRed. We photoconverted the IM at the end of the ND, DIO, and DIO+TRF protocols. Kidneys were analyzed by flow cytometry at 2.5 days post-photoconversion. We detected significantly higher KikRed+ CD8+ T cells in the kidneys of DIO mice compared to ND mice indicating that CD8+ T cells migrate to the kidney from the IM. DIO+TRF mice showed reduced KikRed+ CD8+ T cells in the kidney compared to DIO mice (one-way ANOVA: p=0.006, ND vs DIO: p=0.008; DIO vs TRF: p=0.047). DIO did not have any significant effect on CD4+ T cell migration (one-way ANOVA: p=0.997). This study indicates that DIO induces migration and infiltration of pro-fibrotic CD8+ T cells from the IM to the kidney, while TRF specifically limits migration and infiltration of CD8+ T cells.

The effect of coffee husks used as pellet bedding material on the intestinal barrier, immune-related gene expression and microbiota composition in the broiler chicken caecum

Abstract Introduction Using coffee husks as waste material for bedding contributes to sustainable development. A sustainable choice of bedding has also, however, to be a safe choice for poultry. The study analysed immune-related gene expression in the intestinal mucosa and indicator bacteria in caecal content collected from broiler chickens bedded on material with coffee husk addition. Material and Methods One-day-old Ross 308 chickens were divided into four groups of 10 birds each in five replicates: C, the control group kept on wheat straw bedding; CH10, a group kept on bedding of 10% coffee husks and 90% wheat straw; CH25, a group kept on bedding of 25% husks and 75% straw; and CH50, a group kept on bedding of 50% husks and 50% straw. After 42 days, the birds were slaughtered, the caecal mucosae were removed for RNA isolation and the caecal content was collected for bacterial DNA isolation. The expression of genes involved in intestinal immune response and host organism defence and the relative abundance of indicator bacteria were analysed. Results Upregulation of the expression of genes related to the immune response and intestinal tightness was correlated with an increase in the percentage of coffee husks in the pellet. Coffee husk pellets at 50% bedding content caused a significant numerical increase in Bifidobacterium and a statistically significant increase in Lactobacillus. A significant reduction in E. coli bacteria was also demonstrated in this group. Coffee husk pellets at all content percentages resulted in a statistically significant diminution of the level of Streptococcus bacteria. Conclusion The addition of coffee husks to poultry litter effects beneficial changes in the expression of genes related to intestinal health and the caecal bacterial profile.