Intestinal Cells Research Articles

Lack of effects of polystyrene micro- and nanoplastics on activity and expression of human drug transporters

Micro- and nanoplastics (MPs/NPs) constitute emerging and widely-distributed environmental contaminants to which humans are highly exposed. They possibly represent a threat for human health. In order to identify cellular/molecular targets for these plastic particles, we have analysed the effects of exposure to manufactured polystyrene (PS) MPs and NPs on in vitro activity and expression of human membrane drug transporters, known to interact with chemical pollutants. PS MPs and NPs, used at various concentrations (1, 10 or 100µg/mL), failed to inhibit efflux activities of the ATP-binding cassette (ABC) transporters P-glycoprotein, MRPs and BCRP in ABC transporter-expressing cells. Furthermore, PS particles did not impair the transport of P-glycoprotein or BCRP substrates across intestinal Caco-2 cell monolayers. Uptake activities of solute carriers (SLCs) such as OCT1 and OCT2 (handling organic cations) or OATP1B1, OATP1B3, OATP2B1, OAT1 and OAT3 (handling organic anions) were additionally not altered by PS MPs/NPs in HEK-293 cells overexpressing these SLCs. mRNA expression of ABC transporters and of the SLCs OCT1 and OATP2B1 in Caco-2 cells and human hepatic HepaRG cells were finally not impaired by a 48-h exposure to MPs/NPs. Altogether, these data indicate that human drug transporters are unlikely to be direct and univocal targets for synthetic PS MPs/NPs.

Organization of a cytoskeletal superstructure in the apical domain of intestinal tuft cells.

Tuft cells are a rare epithelial cell type that play important roles in sensing and responding to luminal antigens. A defining morphological feature of this lineage is the actin-rich apical "tuft," which contains large fingerlike protrusions. However, details of the cytoskeletal ultrastructure underpinning the tuft, the molecules involved in building this structure, or how it supports tuft cell biology remain unclear. In the context of the small intestine, we found that tuft cell protrusions are supported by long-core bundles that consist of F-actin crosslinked in a parallel and polarized configuration; they also contain a tuft cell-specific complement of actin-binding proteins that exhibit regionalized localization along the bundle axis. Remarkably, in the sub-apical cytoplasm, the array of core actin bundles interdigitates and co-aligns with a highly ordered network of microtubules. The resulting cytoskeletal superstructure is well positioned to support subcellular transport and, in turn, the dynamic sensing functions of the tuft cell that are critical for intestinal homeostasis.

Aberrant Trafficking of Intestinal Immune Cells in Salt-Sensitive Hypertension

Aberrant Trafficking of Intestinal Immune Cells in Salt-Sensitive Hypertension

Targeted inhibition of Gus-expressing Enterococcus faecalis to promote intestinal stem cell and epithelial renovation contributes to the relief of irinotecan chemotoxicity by dehydrodiisoeugenol

Irinotecan (CPT11) chemotherapy-induced diarrhea affects a substantial cancer population due to β-glucuronidase (Gus) converting 10-O-glucuronyl-7-ethyl-10-hydroxycamptothecin (SN38G) to toxic 7-ethyl-10-hydroxycamptothecin (SN38). Existing interventions primarily address inflammation and Gus enzyme inhibition, neglecting epithelial repair and Gus-expressing bacteria. Herein, we discovered that dehydrodiisoeugenol (DDIE) alleviates CPT11-induced intestinal mucositis alongside a synergistic antitumor effect with CPT11 by improving weight loss, colon shortening, epithelial barrier dysfunction, goblet cells and intestinal stem cells (ISCs) loss, and wound-healing. The anti-mucositis effect of DDIE is gut microbiota-dependent. Analysis of microbiome profiling data from clinical patients and CPT11-induced mucositis mice reveals a strong correlation between CPT11 chemotoxicity and Gus-expressing bacteria, particularly Enterococcus faecalis (E. faecalis). DDIE counters CPT11-induced augmentation of E. faecalis, leading to decreased intestinal Gus and SN38 levels. The Partial Least Squares Path Model (PLS-PM) algorithm initially links E. faecalis to dysregulated epithelial renovation. This is further validated in a 3D intestinal organoid model, in which both SN38 and E. faecalis hinder the formation and differentiation of organoids. Interestingly, colonization of E. faecalis exacerbates CPT11-induced mucositis and disturbs epithelial differentiation. Our study unveils a microbiota-driven, epithelial reconstruction-mediated action of DDIE against mucositis, proposing the ‘Gus bacteria–host–irinotecan axis’ as a promising target for mitigating CPT11 chemotoxicity.

Anticancer properties and prevention of metabolic syndrome by probiotic-enriched powdered human milk

This work aimed to develop a novel formulation based on human milk (HM) enriched with a probiotic formulation comprised of Lactobacillus acidophilus CL1285, Lactobacillus casei LBC80R and Lactobacillus rhamnosus CLR2 and to evaluate in vitro and in vivo anticancer properties and its impact on the prevention of risk factors of metabolic syndrome (MetS). In vitro studies were conducted on Hepa-1c1c7, HT-29, and CHO-K1 cell lines to assess the antiproliferative and anticancer properties of HM and probiotics. The in vivo study was conducted with 28 male Wistar rats fed a high-fat diet (HFD). Rats were daily force-fed with HM and HM + probiotics or water for 8 weeks. Inflammation and oxidative stress were monitored through blood cytokines and kidney investigation. Body weight and blood glucose were recorded throughout the study. The results showed that HM had antiproliferative properties and caused apoptosis of intestinal tumoral cells. Quinone reductase (QR) was induced up to 1.8x in Hepa-1c1c7 cell line demonstrating chemotherapeutic potential. HM enriched with probiotics reduced weight gain by 10% while renal oxidative damages were reduced by up to 97%. Blood insulin and Plasminogen Activator Inhibitor-1 (PAI-1) levels were also significantly reduced. The study showed that HM had antiproliferative and chemopreventive properties on cancer cell lines. The in vivo experiment suggests that the development of a formulation based on HM powder enriched with probiotics could be used to modulate the rate of inflammation and oxidative damage to tissues, thus reducing the risk of obesity-related diseases.

CRISPR screens unveil nutrient-dependent lysosomal and mitochondrial nodes impacting intestinal tissue-resident memory CD8+ T cell formation

Nutrient availability and organelle biology direct tissue homeostasis and cell fate, but how these processes orchestrate tissue immunity remains poorly defined. Here, using invivo CRISPR-Cas9 screens, we uncovered organelle signaling and metabolic processes shaping CD8+ tissue-resident memory T (TRM) cell development. TRM cells depended on mitochondrial translation and respiration. Conversely, three nutrient-dependent lysosomal signaling nodes-Flcn, Ragulator, and Rag GTPases-inhibited intestinal TRM cell formation. Depleting these molecules or amino acids activated the transcription factor Tfeb, thereby linking nutrient stress to TRM programming. Further, Flcn deficiency promoted protective TRM cell responses in the small intestine. Mechanistically, the Flcn-Tfeb axis restrained retinoic acid-induced CCR9 expression for migration and transforming growth factor β (TGF-β)-mediated programming for lineage differentiation. Genetic interaction screening revealed that the mitochondrial protein Mrpl52 enabled early TRM cell formation, while Acss1 controlled TRM cell development under Flcn deficiency-associated lysosomal dysregulation. Thus, the interplay between nutrients, organelle signaling, and metabolic adaptation dictates tissue immunity.

Safflower dietary fiber alleviates functional constipation in rats via regulating gut microbiota and metabolism

A functional constipation rat model was established by loperamide hydrochloride (LOP), and then safflower dietary fiber (SDF) was supplemented to constipated rats. The results revealed that SDF increased the serum levels of excitatory gastrointestinal active peptides such as motilin (MTL), gastrin (GAS), and substance P (SP), while concurrently decreasing the levels of inhibitory peptides like somatostatin (SS) and vasoactive intestinal peptide (VIP). SDF restored the ratio of Firmicutes/Bacteriodetes (F/B), upregulated the relative abundance of Lactobacillus and Clostridium, and downregulated the relative abundance of Oscillopira, Ruminococcus, Coprococcus, and Akkermansia; analysis of metabolites revealed that the levels of bile acid, deoxycholic acid, chenodeoxycholic acid, and taurocholic acid were notably elevated after SDF treatment, while the levels of indole-3-lactic acid, putrescine, and L-arginine were significantly decreased. Pathway enrichment analysis found that SDF regulates Taurine and hypotaurine metabolism, Primary bile acid biosynthesis, and Bile secretion. Correlation analysis between gut microbiota and metabolites revealed that Fusibacter and Actinomyces may contribute to alleviating constipation by regulating the level of bile acid in the intestine. SDF intervention increased the mRNA expressions of FABP1 and SLC1A5 in constipated rats. Furthermore, SDF exhibited notable abilities in retaining water and undergoing swelling. The above results showed that SDF helped the intestine lock water and promoted intestinal peristalsis by increasing friction. On the other hand, SDF supplementation increased the relative abundance of Lactobacillus and Clostridium, decreased the relative abundance of Oscillopira, increased the levels of various bile acids such as deoxycholic acid and chenodeoxycholic acid, further regulated intestinal lipid metabolism, up-regulated FABP1 mRNA expression, promoted intestinal cell proliferation, restored intestinal homeostasis, and thus alleviated constipation.

Research progress of probiotics regulating intestinal micro-ecological environment in obese patients after bariatric surgery

Bariatric surgery may cause intestinal microecological environment imbalance due to changes in gastrointestinal anatomy. Some patients may have compli-cations, even regain weight. Probiotics can act on intestinal mucosa, epithelium and gut-associated lymphoid tissue to improve the intestinal microecological environment of obese patients after bariatric surgery. Probiotics can promote the production of short-chain fatty acids, stimulate intestinal cells to release glucagon-like peptide-1, peptide tyrosine-tyrosine, insulin and other endocrine hormones, affect the function of the central nervous system through the gut-brain axis, make patients after bariatric surgery feel full, and reduce blood sugar at the same time. Probiotics can produce lactic acid, acetic acid and lactase, to inhibit the growth of harmful bacteria and to improve gastrointestinal symptoms of patients after bariatric surgery. Probiotics can activate the AMP-activated protein kinase signaling pathway, improve lipid metabolism, and promote the recovery of symptom indicators of nonalcoholic fatty liver disease after bariatric surgery. Probiotics can regulate the release of neurotransmitters or metabolites by the microbiota through the gut-brain axis to affect brain activity and behavior, thus helping patients improve negative emotions after bariatric surgery. This article describes the intestinal microecological environment of obese patients and mechanism of the change after bariatric surgery and summarizes the effects and possible mechanisms of probiotics in improving the intestinal microecological environment of obese patients after bariatric surgery, to provide references for promoting the clinical application of probiotics.

RpIFN-λ1 alleviates the clinical symptoms of porcine epidemic diarrhea

Porcine epidemic diarrhea (PED), caused by the porcine epidemic diarrhea virus (PEDV), primarily affects the jejunum and ileum of pigs. Interferons, glycoproteins with high species specificity and potent antiviral activity, are crucial in defending against viral infections. Unlike other interferons, interferon-lambda (IFN-λ) mainly acts on mucosal epithelial cells and exhibits robust antiviral activity at mucosal surfaces. However, the high cost limits the use of naturally extracted interferons in farming. In this study, we expressed recombinant porcine interferon-lambda 1 (rpIFN-λ1) in eukaryotic cells, demonstrating effective antiviral activity against PEDV in Vero E6 and IPI-FX cells. In vivo, rpIFN-λ1 alleviated clinical symptoms and intestinal damage, enhanced antioxidant capacity, reduced inflammation, and significantly improved the survival rate of piglets following PEDV infection. Both in vitro and in vivo studies confirmed that rpIFN-λ1 upregulated interferon-stimulated genes (ISGs) via the JAK-STAT pathway, thereby exerting antiviral effects. In conclusion, rpIFN-λ1 significantly inhibited PEDV replication and alleviated clinical symptoms. The selectivity of rpIFN-λ1 for intestinal cells and its ability to reduce viral shedding suggest that this agent is a promising antiviral for enteric viruses such as PEDV. Our findings highlight rpIFN-λ1 as a cost-effective, efficient, and novel strategy for antiviral treatment of PEDV.

Promotion of antibiotic-resistant genes dissemination by the micro/nanoplastics in the gut of snail Achatina fulica

Terrestrial animal intestines are hotspots for the enrichment of micro/nano plastics (M/NPs) and antibiotic-resistant genes (ARGs). However, little is known about the further impact of M/NPs on the spread of ARGs in animal guts. This study investigates the role of M/NPs (polystyrene) with varying particle sizes (0.082, 42, and 182 μm), concentrations (10 and 100 mg/L), and exposure durations (4 and 16 days) in the ARGs dissemination via conjugation in the edible snail (Achatina fulica) gut. Combination of qPCR with 16S rRNA-based sequencing, we found that PS exposure caused intestinal cell impairment and shifts in the gut microbial community of snails. Conjugation rate increased with PS particle sizes in the snail gut. After 4 days of exposure, significantly higher conjugation rates were observed in the gut exposed to 100 mg/L PS compared to 10 mg/L, however, this trend reversed after 16 days. Consistently, the abundances of conjugation relevant genes trfA and trbB shared similar trends to the conjugation ratios in the snail gut after PS exposure. Transconjugant diversity was much lower in 10 mg/L PS groups than in 100 mg/L PS treatments. Therefore, this study suggests that the presence of M/NPs would complicate management of ARG spread. The selection pressure exerted by M/NPs may sustain or even amplify the spread of ARGs in the gut of terrestrial animals even in the absence of antibiotics. It highlights the necessity of avoiding M/NPs intake as a part of comprehensive strategy for cubing ARG dissemination in the gut of animals.

Polyphenols from unconventional fruit by-products protect human epithelial intestinal cells from oxidative damage

Polyphenols from discards of unconventional fruits, namely guava (Psidium guajava L.), jerivá (Syagrus romanzoffiana), butiá (Butia catarinensis), and sea buckthorn (Hippophae rhamnoids L.) have shown in vitro capacity to ameliorate risk factors associated with chronic diseases. To verify their effects in models simulating human physiology, human colorectal adenocarcinoma (Caco-2) cells can be used to reproduce the small intestine's brush border. Therefore, differentiated Caco-2 cells were treated with phenolic extracts from guava processing discards and jerivá, butiá, and sea buckthorn seeds. Cells were assessed for cytotoxicity through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cellular antioxidant activity (CAA) by fluorescence decline of treated cells mixed with a free radical. Selected extract concentrations induced Caco-2 cytotoxicity mostly in the 100–150 μg/mL range. For CAA, extracts from guava, jerivá, and butiá by-products displayed a hormetic-like behavior, showing antioxidant effect at low concentrations while becoming prooxidants at higher concentrations. In some instances, restoration of the antioxidant effect followed, possibly due to cellular adaptative mechanisms. Sea buckthorn seeds extract showed the most consistent CAA response among all samples. Hence, polyphenols from fruit by-products showed antioxidant activity in Caco-2 cells, although future research should concentrate on assessing their absorption and evaluating their effects in other cell models.

Analysis of twelve human milk oligosaccharides over fifteen months post-partum in human milk from Chinese mothers

Human milk Oligosaccharides (HMOs) are a major component in human milk and recognized to play an important role in modulating gut microbiota, intestinal cell response, and the development of the brain and immune system. While HMOs levels from Chinese mothers across different regions of China have been reported, data from Hebei are lacking. Twelve HMOs were measured from a cross-section of Hebei Han mothers over a 15-month lactation period. The average total of the 12 measured HMOs was 4872 ± 1902 mg/L, similar to that reported for Han mothers from other Chinese regions. Hebei Han mothers had much lower LNnT (59.0 ± 53.1 mg/L), LNFP II (257.5 ± 211.0 mg/L) and LNFP III (149.9 ± 121.7 mg/L) levels and higher 3FL levels (1875.2 ± 1065.3 mg/L) compared to other regional Chinese mother cohorts. The distribution of secretor and Lewis status for this Hebei mother cohort was measured at 68.5 %, 21.9 %, 8.2 % and 1.4 % respectively for Se+Le+, Se-Le+, Se+Le- and Se-Le- respectively. The results from this study suggest that location has influence over the HMOs concentration.

Cryosectioning and immunofluorescence of C. elegans reveals endogenous polyphosphate in intestinal endo-lysosomal organelles

Polyphosphate (polyP) is a ubiquitous polyanion present throughout the tree of life. While polyP's widely varied functions have been interrogated in single-celled organisms, little is known about the cellular distribution and function of polyP in multicellular organisms. To study polyP in metazoans, we developed the nematode Caenorhabditis elegans as a model system. We designed a high-throughput, longitudinal-orientation cryosectioning method that allowed us to scrutinize the intracellular localization of polyP in fixed C.elegans using fluorescent polyP probes and co-immunostaining targeting appropriate marker proteins. We discovered that the vast majority of polyP is localized within the endo-lysosomal compartments of the intestinal cells and is highly sensitive toward the disruption of endo-lysosomal compartment generation and food availability. This study lays the groundwork for further mechanistic research of polyPs in multicellular organisms and provides a reliable method for immunostaining hundreds of fixed worms in a single experiment.

Assessing the Impact of Clove (Syzygium Aromaticum) Extract on Intestinal and Hepatic Histological Alterations in Broiler Chickens Infected with Salmonella typhimurium

This study investigated effects of aqueous and ethanolic clove extracts in small intestine and liver of chickens exposed to Salmonella typhimurium. Two hundred fifty-day-old chicks were divided into five groups. Group 1 served as the control and received a basic diet.Group 2 was orally infected with Salmonella typhimurium. Group 3 received same infection but was treated with Ciprofloxacin. Groups 4 and 5 were infected but received treatments of aqueous and ethanolic clove extracts, respectively. The findings revealed that Group 1 exhibited normal small intestine, while Group 2 displayed severe abnormalities, including flattened mucosa, damaged villi, and inflammation. Group 3 showed improvements, increased cell growth and goblet cells in the small intestine. Group 4 displayed nearly normal intestinal features. Group 5 had fully restored intestinal health. In the liver, Group 1 showed typical hepatic structure, whereas Group 2 exhibited signs of inflammation and hepatocyte necrosis. Group 3 displayed severe hepatocyte damage, while Group 4 demonstrated restored liver structure with slight sinusoidal dilation. Group 5 had a well-preserved hepatic architecture with minor inflammation. Administration of 2 mg/kg of aqueous and ethanolic clove extracts demonstrated alleviate histological alterations in small intestine and liver caused by Salmonella typhimurium infection. Notably, the aqueous extract is more effective than ethanolic extract in reducing liver and intestine damage.

Early Weaning Inhibits Intestinal Stem Cell Expansion to Disrupt the Intestinal Integrity of Duroc Piglets via Regulating the Keap1/Nrf2 Signaling.

There are different stress resistance among different breeds of pigs. Changes in intestinal stem cells (ISCs) are still unclear among various breeds of piglets after early weaning. In the current study, Taoyuan Black and Duroc piglets were slaughtered at 21 days of age (early weaning day) and 24 days of age (3 days after early weaning) for 10 piglets in each group. The results showed that the rate of ISC-driven epithelial renewal in local Taoyuan Black pigs hardly changed after weaning for 3 days. However, weaning stress significantly reduced the weight of the duodenum and jejunum in Duroc piglets. Meanwhile, the jejunal villus height, tight junction-related proteins (ZO-1, Occludin, and Claudin1), as well as the trans-epithelial electrical resistance (TEER) values, were down-regulated after weaning for 3 days in Duroc piglets. Moreover, compared with Unweaned Duroc piglets, the numbers of Olfm4+ ISC cells, PCNA+ mitotic cells, SOX9+ secretory progenitor cells, and Villin+ absorptive cells in the jejunum were reduced significantly 3 days after weaning. And ex vivo jejunal crypt-derived organoids exhibited growth disadvantages in weaned Duroc piglets. Notably, the Keap1/Nrf2 signaling activities and the expression of HO-1 were significantly depressed in weaned Duroc piglets compared to Unweaned Duroc piglets. Thus, we can conclude that ISCs of Duroc piglets were more sensitive to weaning stress injury than Taoyuan Black piglets, and Keap1/Nrf2 signaling is involved in this process.

Alpha-1-antitrypsin improves anastomotic healing in intestinal epithelial cells model.

Intestinal anastomosis is a routine procedure in pediatric surgery, with leakage being a significantcomplication. Human alpha1-antitrypsin (AAT), whose physiological serum concentrations range from 0.9-2.0 mg/ml,is known to accelerate wound healing and stimulate the expression of cell proliferation-related genes. Wehypothesized that AAT might enhance anastomotic healing. In a monolayer of non-tumorigenic HIEC-6 epithelial cells derived from fetal intestine a scratch wascreated. Standard medium without (control) or with AAT (0.5 and 1 mg/ml) was added. Cells were observed using aLife-Cell Imaging System. Cell proliferation was assessed, and the expression of proliferation-related genes wasmeasured by qRT-PCR. In the presence of AAT, the scratch closed significantly faster. Cells treated with 1 mg/ml AAT showed 53%repopulation after 8 h and 97% after 18 h, while control cells showed 24% and 60% repopulation, respectively(p < 0.02). The treatment with AAT induced HIEC-6-cell proliferation and significantly increased the mRNA-expressionof CDKN1A, CDKN2A, ANGPTL4, WNT3 and COL3A1 genes. AAT did not change the mRNA-expression of CXCL8 butdecreased levels of IL-8 as compared to controls. At physiological concentrations AAT accelerates the confluence of intestinal cells and increases cellproliferation. The local administration of AAT may bear therapeutic potential to improve anastomotic healing.

Micronization of wholewheat flour increases iron bioavailability from hydrothermally processed wheat flour dough

Cereal products contribute significantly to dietary intake of essential minerals. In wheat, iron and zinc are stored in specific grain structures including the aleurone, scutellum and embryo. Wheat cell walls are resistant to digestion in the human gastrointestinal tract and therefore this study investigated the hypothesis that physical disruption of the cell walls would increase the bioaccessibility and bioavailability of iron and zinc from wheat-based foods. Flour was micronized using a combination of roller milling and a micro-mill and this reduced median particle size by two-thirds. Hydrothermally processed wheat flour doughs were subjected to in vitro digestion to determine mineral bioaccessibility. Mineral bioavailability from food digests was measured using human intestinal Caco-2 cells. Iron (but not zinc) bioavailability from wheat foods made using the micronized flour (2.5 ± 0.5 nmol/mg cell protein) was increased significantly compared with foods produced from standard milled flour (1.3 ± 0.1 nmol/mg cell protein; P = 0.031). Micronization of wheat flour has the potential to increase the absorption of the endogenous iron present in cereal foods and this might have health benefits for population groups with poor iron status.

MiR-27a-3p regulates intestinal cell proliferation and differentiation through Wnt/β-catenin signalling.

Intestinal stem cells differentiate into absorptive enterocytes, characterised by increased brush border enzymes such as intestinal alkaline phosphatase (IAP), making up the majority (95%) of the terminally differentiated cells in the villus. Loss of integrity of the intestinal epithelium plays a key role in inflammatory diseases and gastrointestinal infection. Here, we show that the intestinal microRNA (miR)-27a-3p is an important regulator of intestinal epithelial cell proliferation and enterocyte differentiation. Repression of endogenous miR-27a-3p leads to increased enterocyte differentiation and decreased intestinal epithelial cell proliferation in mouse and human small intestinal organoids. Mechanistically, miR-27a-3p regulates intestinal cell differentiation and proliferation at least in part through the regulation of retinoic acid receptor α (RXRα), a modulator of Wnt/β-catenin signalling. Repression of miR-27a-3p increases the expression of RXRα and concomitantly, decreases the expression of active β-catenin and cyclin D1. In contrast, overexpression of miR-27a-3p mimic decreases the expression of RXRα and increases the expression of active β-catenin and cyclin D1. Moreover, overexpression of the miR-27a-3p mimic results in impaired enterocyte differentiation and increases intestinal epithelial cell proliferation. These alterations were attenuated or blocked by Wnt inhibition. Our study demonstrates an miR-27a-3p/RXRα/Wnt/β-catenin pathway that is important for the maintenance of enterocyte homeostasis in the small intestine.

Selenium nanoparticles affect chicken offspring's intestinal health better than other selenium sources

This study aimed to assess the effects of maternal diets containing various selenium (Se) sources on the intestinal mucosal function in the jejunum of chicken offspring. A total of 630, 18-wk-old Hy-Line Grey hens and 70 18-wk-old Hy-Line Grey breeders were randomly allocated into 7 groups, with 5 replicates in each group (18 hens and tow roosters). After 4 wk of Se depletion, the birds were fed either a nonsupplemented basal diet (control) or the same basal diet supplemented with 0.15 mg/kg selenium nanoparticles (Nano-Se), 0.30 mg/kg Nano-Se, 0.30 mg/kg selenocysteine (Sec), 0.30 mg/kg sodium selenite (SS), 0.30 mg/kg selenomethionine (SeMet), or 0.15 mg/kg Nano-Se + 0.15 mg/kg Sec, for 8 wk. Frtilized eggs were collected and incubated during the final week of the experiment. Jejunal tissues from embryonic d 18 and the hatch day were collected for analysis, and the 7-d survival rate of the offspring was recorded. Compared to the control, the maternal diet of 0.30 mg/kg Nano-Se, 0.30 mg/kg Sec, and 0.30 mg/kg SeMet significantly increased the survival of 7-day-old offspring (P < 0.05). The maternal diet supplemented with 0.30 mg/kg Nano-Se significantly increased intestinal villus height and the villus height/crypt depth ratio in chicks at embryonic d 18 and in 1-day-old (P < 0.05). The maternal diet containing 0.30 mg/kg Nano-Se and Sec increased the mRNA expression levels of tight junction proteins in 1-day-old offspring (P < 0.05). Supplemental 0.30 mg/kg Nano-Se significantly increased the mRNA expression levels of marker genes in intestinal enteroendocrine, stem, and Paneth cells (P < 0.05). In 1-day-old chicks, the number of intestinal goblet cells, as well as the mRNA expression levels of intestinal mucin2 (Muc2) and goblet cell differentiation factors (Spdef and C-myc), were the highest in diets supplemented with 0.30 mg/kg Nano-Se. Moreover, the expression levels of intestinal Muc2 and Spdef in chicks at embryonic d 18 was the highest with 0.30 mg/kg Nano-Se supplementation (P < 0.05). Supplementing with 0.30 mg/kg Nano-Se significantly reduced reactive oxygen species levels and decreased the mRNA expression levels of apoptosis-related genes in 1-day-old chicks (P < 0.05). Additionally, 0.30 mg/kg Nano-Se supplementation significantly down-regulated NLRP3 pathway gene expression in 1-day-old chicks (P < 0.05). In conclusion, maternal dietary supplementation with Nano-Se improved jejunal microarchitecture, antioxidant levels, and the expression of tight-junction protein in chicken offspring along with supporting goblet cell development by inhibiting the NLRP3 signaling pathway.

Evaluation of in vitro probiotic properties and colonization of Brevibacillus Laterosporus S62-9 in the intestine of broiler chickens

Brevibacillus laterosporus has been used as a direct-fed microbial additive in chicken feed owing to its strain safety and the ability to produce broad-spectrum antimicrobial peptides. To assess the efficacy and persistence of Brevibacillus laterosporus, it is necessary to track the supplied strains throughout the gastrointestinal tract. This study aims to evaluate the in vitro probiotic properties of Brevibacillus laterosporus S62-9 and its capacity to colonize and persist in the intestines of broiler chickens. Results indicated that the spores of Brevibacillus laterosporus S62-9 exhibited higher tolerance to the digestive condition, and higher adhesion rate to mucus and intestinal cells compared to vegetative cells. The spores remained dormant during digestion in the crop and stomach but germinate in the small intestine with a germination rate exceeding 70%. Subsequently, the whole genome of S62-9 was sequenced, and specific primers were designed and validated based on comparative genome analysis. The quantitative PCR-based method had a detection limit ranging from 2.71 to 7.71 log10 CFU/mL in pure culture and from 3.25 to 9.25 log10 CFU/g in broiler cecal content. In vivo colonization assay indicated that the Brevibacillus laterosporus S62-9 can transiently colonize the broiler cecum. In summary, our results indicated that the Brevibacillus laterosporus S62-9 spores exhibited high tolerance to the digestive tract environment, germinated in the intestine, and establish colonization in the cecum of broilers. The findings provide a theoretical basis for the future application of Brevibacillus laterosporus S62-9 in broiler farming.