Intestinal Oxidative Stress Research Articles

The dysfunction in intestinal microorganisms and enzyme activity as significant contributors to diarrhea with kidney-yang deficiency syndrome.

To investigate the pathogenesis of diarrhea with kidney-yang deficiency syndrome by examining characteristic changes in intestinal microorganisms, enzyme activities, oxidative stress, and metabolism indices. Twenty mice were randomly and equally divided into control group (NC) and model group (NM). Mice in NM group received adenine suspension at a dosage of 50 mg/(kg⋅day) by gavage, 0.4 mL/time, once a day for 14 days, and Folium sennae decoction at a dosage of 10 g/(kg⋅day) by gavage, 0.4 mL/time, once a day for 7 days, starting on 8th day. Mice in NC group were administered an equivalent amount of sterile water by gavage once a day for 7 days, and twice a day from the 8th day. After modeling, assessments encompassed microbial culture, organ index calculation, microbial and enzyme activity detection, malondialdehyde (MDA) content determination, superoxide dismutase (SOD) activity, blood biochemical tests, and observation of kidney tissue pathological changes. The results showed that in NM group, a reduction in the number of Lactobacillus and Bifidobacteria was noted, accompanied by an increase in the number of bacteria and E. coli. Xylanase activity in the intestinal contents and mucosa, protease activity in the intestinal mucosa, and intestinal mucosa microbial activity were diminished. Conversely, the activities of amylase, sucrase, and lactase increased in intestinal mucosa. Additionally, there was an elevation in the level of MDA. Renal tubular dilatation and inflammatory cell infiltration were observed in the renal interstitium. These dysfunctions in intestinal microorganisms and enzyme activities suggest potential involvement in diarrhea with kidney-yang deficiency syndrome.

Zinc intake ameliorates intestinal morphology and oxidative stress of broiler chickens under heat stress.

Zinc (Zn), an essential trace element for poultry, plays a crucial role in promoting growth, improving feed conversion efficiency, enhancing antioxidant activity, and preventing disease. This study investigated the impact of different levels and sources of dietary Zn supplementation on the growth performance, intestinal morphology and antioxidant activity of broiler chickens under heat stress conditions. In this experiment, 1024 Xueshan chickens were divided into eight groups and subjected to heat stress conditions with different levels of Zn supplementation (30 mg/kg, 60 mg/kg, and 90 mg/kg) using organic or inorganic sources. Our findings indicated that dietary Zn supplementation significantly increased the feed-to-weight ratio of broilers during the experimental period under heat stress. Moreover, Zn supplementation positively increased the villus height and villus width in the jejunum and ileum at 74 and 88 days old, with the 60 and 90 mg/kg groups outperforming other groups, and organic Zn was more effective than inorganic Zn. Furthermore, Zn supplementation significantly increased serum antioxidant levels, with higher superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH-px) activities, and organic Zn was more effective than inorganic Zn. This study concludes that Zn supplementation is beneficial in mitigating the detrimental impacts of heat stress on broilers. The findings suggest that employing Zn as a strategy can enhance productivity in the poultry industry by positively influencing intestinal morphology and bolstering antioxidant activity to counteract potential stress.

Argininyl-Fructosyl-Galactose: A Novel Amino Acid Derivative improves Cisplatin-induced Intestinal Toxicity via Reactive Oxygen Species- mediated Apoptosis Pathway.

Based on the Maillard reaction principle of red ginseng, this study innovatively synthesized a new amino acid derivative by combining arginine with lactose through simulated synthesis and was separated and purified through repeated silica gel and polyacrylamide gel (Bio-gel P-II) column chromatography. The work was aimed at elucidating the synthesis of a novel amino acid derivative and investigating the intestinal protective activity of the novel amino acid derivative and possible molecular mechanism by establishing the intestinal injury model induced by cisplatin in mice. The purity and molecular weight of the amino acid derivatives were determined to be by electrospray ionization mass spectrometry (ESI-MS). Subsequently, by establishing cisplatin (20 mg/kg)-induced intestinal injury in vivo for 10 days and IEC-6 cell model. The biochemical indexes and histopathological analysis were used to evaluate the oxidative stress and inflammatory and pathological changes of intestinal tissue in mice. The protein expression levels of p-Nuclear transcription factor-κB (p-NF-κB), cleaved caspase 3/caspase 3, cleaved caspase 9/caspase-9, Bcl-2, Bax, cytochrome C, phosphatidylinositol 3-kinase (PI3K), Protein Kinase B (Akt), p-PI3K, p-Akt were quantified through immunofluorescence staining and western blot analysis. The new amino acid derivatives of chemical structure were identified to be 1- (arginine-Nαgroup)-1-deoxy-4-O-(β-D-galactopyranosyl)-D-fructose, named Argininylfructosyl- galactose (AFGA, C18H34N4O12). The results showed that pretreatment with a single AFGA dose remarkably alleviated cisplatin-evoked intestinal oxidative stress injury, and the levels of reactive oxygen species (ROS) were lessening in IEC-6 cells (p<0.05, p<0.01) and could effectively reduce the secretion of TNF-α and IL-1β in serum and the expression level of NF-κB protein in intestinal tissues (p<0.01). Meantime, AFGA also significantly suppressed the caspase 3, caspase 9, cytochrome C and Bax protein expression in intestinal tissue in mice (p<0.01), and regulated the PI3K/Akt pathway (p<0.05, p<0.01). Importantly, the molecular docking results of AFGA also suggested a better binding ability with the above-mentioned related target proteins. The results clearly revealed AFGA as a potential multifunctional therapeutic agent with a clear protective effect against cisplatin-induced intestinal injury may be related to the PI3K/Akt signaling pathway.

In vivo oral toxicity and antioxidant capacity of Nothofagus antarctica (G.Forst.) oerst (ñire) leaves

ABSTRACT Nothofagus antarctica (NA) is a native tree of Patagonia. Since ancient times, NA leaves were used in infusions for medical and food purposes, but there are no deep insights on its toxicity. The aim of this work was to assess the safety and antioxidant activity of NA leaves infusion. Mice were used to determine acute and subacute oral toxicity. Total polyphenols, flavonoids and the antioxidant activity of the infusion were assessed, as well as the antioxidant activity in biological samples. Toxicity tests revealed no death or signs of toxicity. No significant differences in biochemical parameters/histological structure were registered. NA infusion exhibited a high content of polyphenols and flavonoids, contributing to its remarkably antioxidant activity. The periodic administration of NA infusion could increase the antioxidant capacity in mice at intestinal level. The results support the safe of consuming NA leaves infusion and suggest their contribution for modulating the intestinal oxidative stress.

Effects of Resistant Starch Supplementation on Metabolic Parameters and Oxidative Stress in C57BL/6 Mice Fed With a High‐Fat Diet

Normolipid supplemented with resistant starch (RS) is a type of dietary fiber with prebiotic properties, potential action on intestinal permeability, and an effect on decreasing glycemic levels, presenting therapeutic potential for issues stemming from excess body fat and associated comorbidities, such as nonalcoholic fatty liver disease (NAFLD). Sixty C57BL/6 mice were allocated to the following diets for 4 months: control (C), normolipid rich in fiber (F), RS, high fat (HL), HL rich in fiber (HLF), and HL supplemented with RS (HLRS). The following parameters were analyzed: animal weight, body composition, food intake, fasting blood glucose, lipid profile, hepatic and intestinal histology, hepatic and intestinal oxidative stress, and assessment of short‐chain fatty acids in feces. Long‐term supplementation with high doses of RS effectively reduced body weight gain and decreased liver and retroperitoneal adipose tissue weights, blood glucose levels, alanine aminotransferase, and serum triglycerides. Intestinal histology showed that the high‐fat diet increased the total diameter of the intestinal lumen (846.81 ± 7.82) and reduced enteric muscle thickness (8.51 ± 0.51), while RS supplementation effectively improved these parameters (658.01 ± 3.82; 30.56 ± 0.66), also increased butyrate production, and reduced oxidative stress in the intestine. RS supplementation was effective in reducing weight, adiposity, and NAFLD in mice with diet‐induced obesity and metabolic syndrome (MS).

Sirtuin 3 ameliorates inflammatory bowel disease via inhibiting intestinal inflammation and oxidative stress.

Sirtuin 3 involved in development of various diseases, but its role in inflammatory bowel disease is still unknown. We used inflammatory bowel disease biopsies, colitis animal model, and vitro cells RAW264.7 to study the role of Sirtuin 3 in the pathophysiology of inflammatory bowel disease. Sirtuin 3 negatively correlated with intestinal TNF-α. Sirt3 was less pronounced in pediatric and adult inflammatory bowel disease patients compared with corresponding control group. Sirtuin 3 activator Honokiol suppressed dextran sulfate sodium induced colonic manifestations, while Sirt3 inhibitor caused opposite results. Honokiol inhibited colonic oxidative stress by and reduced intestinal permeability. Honokiol repressed inflammatory response by reducing macrophage infiltration, pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 levels, and inhibiting activation of NF-κB p65 in the colitis mice. However, Sirt3 inhibitor amplified colonic oxidative stress and inflammatory response. In vitro study, Sirt3 inhibitor or siRNA Sirtuin 3 activated NF-κB p65 and enhanced TNF-α, IL-1β, and IL-6 secretion from LPS stimulated RAW264.7, while Honokiol remarkably attenuated these pro-inflammatory cytokines secretion. Finally, knockdown of Sirt3 in Caco-2 cells enhanced TNF-α induced intestinal barrier integrity injury. Sirtuin 3 negatively regulates inflammatory bowel disease progression via reducing colonic inflammation and oxidative stress. Sirtuin 3 is a promising therapeutic target in clinical application for inflammatory bowel disease therapy.

Bacillus amyloliquefaciens attenuates the intestinal permeability, oxidative stress and endoplasmic reticulum stress: transcriptome and microbiome analyses in weaned piglets.

Endoplasmic reticulum (ER) stress is related to oxidative stress (OS) and leads to intestinal injury. Bacillus amyloliquefaciens SC06 (SC06) can regulate OS, but its roles in intestinal ER stress remains unclear. Using a 2 × 2 factorial design, 32 weaned piglets were treated by two SC06 levels (0 or 1 × 108 CFU/g), either with or without diquat (DQ) injection. We found that SC06 increased growth performance, decreased ileal permeability, OS and ER stress in DQ-treated piglets. Transcriptome showed that differentially expressed genes (DEGs) induced by DQ were enriched in NF-κB signaling pathway. DEGs between DQ- and SC06 + DQ-treated piglets were enriched in glutathione metabolism pathway. Ileal microbiome revealed that the SC06 + DQ treatment decreased Clostridium and increased Actinobacillus. Correlations were found between microbiota and ER stress genes. In conclusion, dietary SC06 supplementation increased the performance, decreased the permeability, OS and ER stress in weaned piglets by regulating ileal genes and microbiota.

Therapeutic potential of the probiotic Lactiplantibacillus plantarum BX 62 and its postbiotics in alleviating rheumatoid arthritis in mice

This study comprehensively investigated the probiotic potential of Lactiplantibacillus plantarum and its derived postbiotics in alleviating rheumatoid arthritis (RA) symptoms in mice. In vitro analyses established the probiotic characteristics of L. plantarum, highlighting its acid tolerance, bile salt resistance, and adhesion abilities. Subsequent in vivo experiments demonstrated that administering live L. plantarum significantly reduced arthritis scores, paw oedema, and intestinal permeability in RA mice, indicating its therapeutic potential. Furthermore, the study explored the effects of L. plantarum-derived postbiotics, including both the cellular remnants and supernatant, on RA. Notably, both the inactivated body of L. plantarum and its supernatant effectively reduced osteoarthritic damage, intestinal pathological changes, autoantibody levels, cytokine imbalances, and oxidative stress in RA mice. Additionally, qPCR analysis revealed that L. plantarum interventions restored gut microbiota composition towards a healthier profile, resembling that of normal mice. Collectively, these findings underscore the therapeutic benefits of L. plantarum and its postbiotics in ameliorating RA symptoms, emphasising their potential as novel therapeutic agents for managing RA.

Goat milk derived small extracellular vesicles ameliorate LPS-induced intestinal epithelial barrier dysfunction, oxidative stress, and apoptosis by inhibiting the MAPK signaling pathway.

Intestinal injury is often accompanied by epithelial barrier dysfunction, oxidative stress, and apoptosis. Previous research studies have demonstrated that small extracellular vesicles (sEVs) from animal milk play a crucial role in regulating intestinal injury. Nonetheless, there has been limited research on the impact of goat milk sEVs on intestinal damage. This study aims to explore the functional differences between proteins in colostrum-derived sEVs (CME) and mature milk-derived sEVs (MME) from goat and elucidate their effects and mechanisms on lipopolysaccharide (LPS)-induced injury in IEC-6. Proteomic analysis revealed that both CME and MME are rich in various bioactive proteins that have regulatory effects on cell damage. CME and MME significantly improved LPS-induced IEC-6 barrier dysfunction and oxidative stress. Additionally, CME and MME alleviated LPS-induced IEC-6 proliferation inhibition and apoptosis. Notably, CME exhibited a more significant improvement effect. RNA-Seq analysis indicated that CME ameliorates IEC-6 injury by inhibiting multiple genes and signaling pathways associated with cell damage, particularly the MAPK signaling pathway. In summary, goat milk-derived sEVs improve LPS-induced IEC-6 injury by targeting the MAPK signaling pathway, significantly restoring the intestinal epithelial barrier function, reducing oxidative stress, and alleviating apoptosis. These findings offer scientific evidence supporting the potential application of goat milk-derived sEVs as protective agents against intestinal injury.

Aloe polysaccharides ameliorate obesity-associated cognitive dysfunction in high-fat diet-fed mice by targeting the gut microbiota and intestinal barrier integrity.

Aloe polysaccharides (APs) display cognition-improving properties, but the underlying mechanisms remain unclear. Herein, AP supplementation for 24 weeks significantly improved cognitive behavioral disturbances caused by a high-fat diet. Moreover, APs notably reshaped the structure of the gut microbiota, which was manifested by increasing the relative abundance of Alloprevotella, Alistipes, Romboutsia, Turicibacter, Prevotellaceae_UCG-001, and Akkermansia while reducing the abundance of Parasutterella, Staphylococcus, Helicobacter, Enterococcus, and Erysipelatoclostridium. Notably, the gut barrier damage and LPS leakage caused by HF were recovered by APs. Additionally, with the improvement of intestinal barrier integrity, oxidative stress and inflammation in the brain and jejunum were significantly ameliorated. Furthermore, the expression of genes associated with cognitive impairment and the intestinal tract barrier was up-regulated (CREB, BDNF, TrkB, ZO-1 and occludin), while the expression of genes associated with inflammatory factors was down-regulated (IL-1β, IL-6, and TNF-α). Finally, we observed a significant correlation among cognition-related genes, gut microbiota, oxidative stress, and inflammation in the HF-AP group. Together, our findings suggest that altered gut microbiota composition and improved gut barrier integrity may be important targets for potentially improving high-fat diet-induced cognitive impairment.

Urolithin B protects mice from diet-induced obesity, insulin resistance, and intestinal inflammation by regulating gut microbiota composition.

The increasing prevalence of obesity and type 2 diabetes (T2D) signifies the failure of conventional treatments for these diseases. The gut microbiota has been proposed as a key player in the pathophysiology of diet-induced T2D. Urolithin B (Uro B), a gut microbiota-derived polyphenol metabolite, exerts several beneficial health effects. In this study, we investigated the metabolic effects of Uro B on high-fat/high-sucrose (HFHS)-fed mice and determined whether its antidiabetic effects are related to the modulation of the gut microbiota. C57BL/6J mice were fed either a chow or HFHS diet. HFHS-fed mice were administered daily with either a vehicle (water) or different doses of Uro B (100 or 200 mg kg-1) for eight weeks. The composition of the gut microbiota was assessed by 16S rRNA sequencing. The results showed that Uro B treatment reduced HFHS-induced weight gain and visceral obesity and decreased liver weight and triglyceride accumulation associated with blunted hepatic oxidative stress and inflammation. Furthermore, Uro B administration improved insulin sensitivity as revealed by improved insulin tolerance, a lower homeostasis model assessment of insulin resistance, and decreased glucose-induced hyperinsulinemia during the oral glucose tolerance test. Uro B treatment was found to lower the intestinal triglyceride content and alleviate intestinal inflammation and oxidative stress. Remarkably, Uro B treatment markedly increased the proportion of the mucin-degrading bacterium Akkermansia in metagenomic samples. In conclusion, Uro B exerts beneficial metabolic effects by alleviating HFHS diet-induced features of metabolic syndrome, which is associated with a proportional increase in the population of Akkermansia spp.

Lactobacillus reuteri JCM 1112 ameliorates chronic acrylamide-induced glucose metabolism disorder via the bile acid-TGR5-GLP-1 axis and modulates intestinal oxidative stress in mice.

Acrylamide (AA) is a toxic food contaminant that has been reported to cause glucose metabolism disorders (GMD) at high doses. However, it is unclear whether chronic low-dose AA can induce GMD and whether probiotics can alleviate AA-induced GMD. Here, C57BL/6N mice were orally administered with 5 mg per kg bw AA for 10 weeks, followed by another 3 weeks of glucagon-like peptide-1 (GLP-1) analogue (dulaglutide) treatment. Chronic low-dose AA exposure increased the blood glucose level and decreased serum insulin and GLP-1 levels, whereas dulaglutide treatment decreased the blood glucose level and increased the serum insulin level in AA-exposed mice. Then, mice were administered with AA or AA + INT-777 (Takeda G-protein-coupled receptor 5 (TGR5) agonist) for 10 weeks. INT-777 treatment reversed AA-induced downregulation of ileal TGR5 and proglucagon (PG) gene expression and decreased the serum GLP-1 level. These findings indicated that chronic low-dose AA induced GMD via inhibiting the TGR5-GLP-1 axis. Finally, mice were administered with AA for 10 weeks, followed by another 3 weeks of Lactobacillus reuteri JCM 1112 supplementation. L. reuteri supplementation significantly increased serum glucose, insulin and GLP-1 levels, upregulated ileal TGR5 and PG gene expression, and effectively restored the imbalance of bile acid (BA) metabolism in AA-exposed mice, demonstrating that L. reuteri ameliorates chronic AA-induced GMD via the BA-TGR5-GLP-1 axis. In addition, L. reuteri significantly enhanced ileal superoxide dismutase and catalase activities and total antioxidant capacity, thereby preventing chronic AA-induced oxidative stress. Our research provides new insights into the GMD toxicity of chronic low-dose AA and confirms the role of probiotics in alleviating AA-induced GMD.

Effects of hesperidin on mitochondrial function, mitochondria-associated endoplasmic reticulum membranes and IP3R-MCU calcium axis in the intestine of piglets exposed to deoxynivalenol.

Deoxynivalenol (DON) pollution is prevalent in crops, and can induce oxidative stress and intestinal injury. Hesperidin is one of the major flavonoids in citrus fruits that has various biological activities such as antioxidant and anti-inflammatory activities. However, whether hesperidin could alleviate DON-induced intestinal injury and the mechanism remain unclear. Mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) have attracted attention for their crucial signaling points to regulate ER-mitochondria calcium transfer. This study aims to evaluate the effects of hesperidin on the intestinal barrier, mitochondrial function, MAMs, and inositol 1,4,5-triphosphate receptor (IP3R)-mitochondrial calcium uniporter (MCU) calcium axis in the intestine of piglets exposed to DON. Twenty-four piglets were randomly divided into four groups in a 2 × 2 factorial arrangement for a 21-d experiment: Control: basal diet; hesperidin group: basal diet + 300 mg kg-1 hesperidin; DON: basal diet + 1.5 mg kg-1 DON; DON + hesperidin group: basal diet + 1.5 mg kg-1 DON + 300 mg kg-1 hesperidin. The data showed that when compared with the DON group, hesperidin improved growth performance and the intestinal barrier, alleviated intestinal oxidative stress and ER stress, and decreased the serum alanine aminotransferase (ALT) level (P < 0.05). Hesperidin also alleviated mitochondrial dysfunction and ferroptosis in the intestine of piglets exposed to DON (P < 0.05). Importantly, hesperidin prevented excessive MAM formation by downregulating the protein levels of Mitofusin 2 (Mfn2) and glucose-regulated protein 75 (GRP75), decreasing the ratio of the mitochondria with MAMs/total mitochondria and the ratio of MAM length/mitochondrial perimeter and lengthening the mitochondria-ER distance in MAMs (P < 0.05). Furthermore, hesperidin regulated the IP3R-glucose-regulated protein 75 (GRP75)-voltage-dependent anion channel 1 (VDAC1)-MCU calcium axis by decreasing the protein levels of GRP75 and MCU and the calcium level of the mitochondria compared with the DON group (P < 0.05). An in vitro experiment was conducted to further explore whether IP3R-mediated ER-mitochondria calcium transfer was involved in the protective effects of hesperidin on the intestinal epithelium barrier and mitochondria. Data showed that hesperidin may exert protective effects on the intestinal epithelium barrier and mitochondria via inhibiting ER-mitochondrial calcium transfer mediated by IP3Rs. These data suggested that hesperidin could alleviate MAM-mediated mitochondrial calcium overload, thereby improving mitochondrial function and alleviating oxidative stress and intestinal injury in DON-challenged piglets.

Wheat peptides inhibit the activation of MAPK and NF-κB inflammatory pathways and maintain epithelial barrier integrity in NSAID-induced intestinal epithelial injury.

The use of non-steroidal anti-inflammatory drugs (NSAIDs) has negative effects on the gastrointestinal tract, but the proton pump inhibitors currently in use only protect against gastrointestinal disease and may even make NSAID-induced enteropathy worse. Therefore, new approaches to treating enteropathy are required. This study aimed to investigate the protective effect of wheat peptides (WPs) against NSAID-induced intestinal damage in mice and their mechanism. Here, an in vivo mouse model was built to investigate the protective and reparative effects of different concentrations of WPs on NSAID-induced intestinal injury. WPs ameliorated NSAID-induced weight loss and small intestinal tissue damage in mice. WP treatment inhibited NSAID-induced injury leading to increased levels of oxidative stress and expression levels of inflammatory factors. WPs protected and repaired the integrity and permeability injury of the intestinal tight junction induced by NSAIDs. An in vitro Caco-2 cell model was built with lipopolysaccharide (LPS). WP pretreatment inhibited LPS-induced changes in the Caco-2 cell permeability and elevated the levels of oxidative stress. WPs inhibited LPS-induced phosphorylation of NF-κB p65 and mitogen-activated protein kinase (MAPK) signaling pathways and reduced the expression of inflammatory factors. In addition, WPs increased tight junction protein expression, which contributed to improved intestinal epithelial dysfunction. Our results suggest that WPs can ameliorate NSAID-induced impairment of intestinal barrier functional integrity by improving intestinal oxidative stress levels and reducing inflammatory factor expression through inhibition of NF-κB p65 and MAPK signaling pathway activation. WPs can therefore be used as potential dietary supplements to reduce NSAID-induced injury of the intestine.

A Prunus avium L. Infusion Inhibits Sugar Uptake and Counteracts Oxidative Stress-Induced Stimulation of Glucose Uptake by Intestinal Epithelial (Caco-2) Cells.

Sweet cherry (Prunus avium L.) is among the most valued fruits due to its organoleptic properties and nutritional worth. Cherry stems are rich in bioactive compounds, known for their anti-inflammatory and antioxidant properties. Innumerable studies have indicated that some bioactive compounds can modulate sugar absorption in the small intestine. In this study, the phenolic profile of a cherry stem infusion was investigated, as well as its capacity to modulate intestinal glucose and fructose transport in Caco-2 cells. Long-term (24 h) exposure to cherry stem infusion (25%, v/v) significantly reduced glucose (3H-DG) and fructose (14C-FRU) apical uptake, reduced the apical-to-basolateral Papp to 3H-DG, and decreased mRNA expression levels of the sugar transporters SGLT1, GLUT2 and GLUT5. Oxidative stress (induced by tert-butyl hydroperoxide) caused an increase in 3H-DG uptake, which was abolished by the cherry stem infusion. These findings suggest that cherry stem infusion can reduce the intestinal absorption of both glucose and fructose by decreasing the gene expression of their membrane transporters. Moreover, this infusion also appears to be able to counteract the stimulatory effect of oxidative stress upon glucose intestinal uptake. Therefore, it can be a potentially useful compound for controlling hyperglycemia, especially in the presence of increased intestinal oxidative stress levels.

The Use of Fruit and Vegetable by-Products as Enhancers of Health Status of Piglets after Weaning: The Role of Bioactive Compounds from Apple and Carrot Industrial Wastes.

At weaning, piglets are exposed to a large variety of stressors, from environmental/behavioral factors to nutritional stress. Weaning transition affects the gastrointestinal tract especially, resulting in specific disturbances at the level of intestinal morphology, barrier function and integrity, mucosal immunity and gut microbiota. All these alterations are associated with intestinal inflammation, oxidative stress and perturbation of intracellular signaling pathways. The nutritional management of the weaning period aims to achieve the reinforcement of intestinal integrity and functioning to positively modulate the intestinal immunity and that of the gut microbiota and to enhance the health status of piglets. That is why the current research is focused on the raw materials rich in phytochemicals which could positively modulate animal health. The composition analysis of fruit, vegetable and their by-products showed that identified phytochemicals could act as bioactive compounds, which can be used as modulators of weaning-induced disturbances in piglets. This review describes nutritional studies which investigated the effects of bioactive compounds derived from fruit (apple) and vegetables (carrot) or their by-products on the intestinal architecture and function, inflammatory processes and oxidative stress at the intestinal level. Data on the associated signaling pathways and on the microbiota modulation by bioactive compounds from these by-products are also presented.

Influence of artificial digestion on characteristics and intestinal cellular effects of micro-, submicro- and nanoplastics

The production of plastics is rising since they have been invented. Micro, submicro- and nanoplastics are produced intentionally or generated by environmental processes, and constitute ubiquitous contaminants which are ingested orally by consumers. Reported health concerns include intestinal translocation, inflammatory response, oxidative stress and cytotoxicity. Every digestive milieu in the gastrointestinal tract does have an influence on the properties of particles and can cause changes in their effect on biological systems. In this study, we subjected plastic particles of different materials (polylactic acid, polymethylmethacrylate, melamine formaldehyde) and sizes (micro- to nano-range) to a complex artificial digestion model consisting of three intestinal fluid simulants (saliva, gastric and intestinal juice). We monitored the impact of the digestion process on the particles by performing Dynamic Light Scattering, Scanning Electron Microscopy and Asymmetric Flow Field-Flow Fractionation. An in vitro model of the intestinal epithelial barrier was used to monitor cellular effects and translocation behavior of (un)digested particles. In conclusion, artificial digestion decreased cellular interaction and slightly increased transport of all particles across the intestinal barrier. The interaction with organic matter resulted in clear differences in the agglomeration behavior. Moreover, we provide evidence for polymer-, size- and surface-dependent cellular effects of the test particles.

Effects of Dietary Bile Acids on Growth Performance, Lipid Deposition, and Intestinal Health of Rice Field Eel (Monopterus albus) Fed with High-Lipid Diets.

The purpose of this trial was to study the positive effects of bile acids (BAs) on growth performance and intestinal health of rice field eel fed with high-lipid diets (HLDs). Rice field eels (initial weight 17.00 ± 0.10 g) were divided into four groups, each group containing four repetitions and feeding with different isonitrogenous diet: control diet containing 7% lipid content, HLDs containing the lipid content increased to 13%, HLDs supplementing with 0.025% BAs and 0.05% BAs, respectively. After 8 weeks, compared control group, the fish fed HLDs had no significant effect on weight gain rate and specific growth rate (P > 0.05), but increased the lipid deposition in tissues and intestinal lipase activity, and damaged to intestinal oxidative stress, inflammatory response, physical barrier, and structural integrity (P < 0.05). Dietary BAs significantly increased weight gain rate and specific growth rate in fish fed with HL diets (P < 0.05) and reduced feed conversation rate (P < 0.05). Further, the eels fed with BAs reduced the total lipid content in liver, muscle, and whole body (P < 0.05). Dietary BAs decreased the activity of intestinal lipase (P < 0.05). Meanwhile, BAs supplemented in HLDs improved intestinal antioxidant capacity through increasing the activities of T-SOD (total superoxide dismutase), GSH-PX (glutathione peroxidase), CAT (catalase), T-AOC (total antioxidant capacity), whereas reducing MDA (malondialdehyde) content (P < 0.05). Moreover, dietary BAs regulated the mRNA expression related to inflammatory response, oxidative stress, and physical barrier in intestine, such as tnf-α, il-8, tlr-8, il-10, nrf2, keap1, claudin12, and claudin15 (P < 0.05). Dietary BAs supplementation also enhanced the intestinal structural integrity characterized by increased fold height and lamina propria width (P < 0.05). This study showed that dietary BAs supplemented in HLDs (13% lipid) could increase the growth performance of rice field eel, reduce lipid deposition in tissues and whole body, and enhance intestinal health.

Protective effect of electroacupuncture at ST36 against damage of intestinal mucosa, oxidative stress and apoptosis induced by 5-FU chemotherapy in mice with colon cancer.

To observe the effect of electroacupuncture (EA) at "Zusanli"(ST36) on intestinal mucosal damage, intestinal mucosal oxidative stress injury and apoptosis induced by 5-fluorouraeil (5-FU) chemotherapy in colorectal cancer-bearing mice. Thirty male BALB/c mice were randomly divided into normal control, colorectal cancer (CT26), 5-FU, non-acupoint and ST36 groups, with 6 mice in each group. Except for those of the normal control group, mice of the remaining 4 groups received subcutaneous implantation of colorectal CT26 cell suspension (0.1 mL) in the right armpit for establishing colorectal cancer model. Rats of the 5-FU group, non-acupoint group and ST36 group were given with 5 mg/mL 5-FU solution once every 3 days for a total of 21 days. For mice of the non-acupoint group and ST36 group, EA (2 Hz, 1-2 mA) was applied to bilateral ST36 or non-acupoints (the bilateral sunken spots about 3 mm to the midpoint between the tail root and the anus) for 5 min after each intraperitoneal infusion of 5-FU, once every 3 days, for a total of 21 days. After the intervention, the diarrhea index was assessed. The length of colon (from the endpoint of cecum to the anal orifice) was measured. Histopathological changes of colonic mucosa were observed by H.E. staining, and the length of colonic villi was measured. The content of malondialdehyde (MDA), and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) of colonic tissue were detected by thibabituric acid, xanthine oxidase and colorimetric method, respectively. The rate of cell apoptosis in the colonic tissue was measured by TUNEL assay. The positive expressions of Bax and Bcl-2 in colonic tissue were determined by immunohistochemistry. The CT26 model group didn't show any significant changes in the diarrhea index, colon length, colon villus length, MDA content, SOD and GSH-Px activities, colonic cell apoptosis rate, and Bax and Bcl-2 expression levels when compared with the normal group. Compared with the CT26 group, the 5-FU group had a remarkable increase in the diarrhea index, MDA content, colonic cell apoptosis rate and Bax expression level (P<0.01, P<0.05), and a marked decrease in the colon length, colon villus length, SOD and GSH-Px activities and Bcl-2 expression level (P<0.01), suggesting the side effects of administration of 5-FU. Compared with the 5-FU group, the diarrhea index, MDA content, colonic cell apoptosis rate and Bax expression level were markedly decreased (P<0.05, P<0.01) and those of the colon length, colon villus length, SOD and GSH-Px activities and Bcl-2 expression level were obviously increased (P<0.01) in the ST36 group. Compared with the 5-FU group, the non-acupoint group also had an increase in the colon villus length, SOD and GSH-Px activities (P<0.01, P<0.05) and a decrease in the cell apoptosis rate (P<0.01). EA at ST36 has a positive effect in reducing intestinal mucosal damage induced by 5-FU chemotherapy in cancer-bearing mice, which may be related to its function in relieving oxidative stress injury and inhibiting apoptosis of colonic tissue.

Probiotic Lactobacillus plantarum SHY21-2 protected zebrafish against Aeromonas hydrophila infection by maintaining intestinal barrier integrity, inhibiting inflammatory and oxidative stress responses, and regulating intestinal microbiome

Lactic acid bacteria are generally regarded as an effective alternative to antibiotics in aquaculture farming, especially Lactobacillus strains, which are safe and have probiotic potential. However, the mechanism of action of probiotic Lactobacillus in protecting fish against Aeromonas hydrophila infection remains unclear. In this study, a strain of Lactobacillus plantarum SHY21-2, was investigated for its safety and probiotic properties using a combination of phenotypic and whole-genome analysis. The results revealed that SHY21-2 has good safety, antimicrobial activity, and multiple probiotic properties, including tolerance to acid and bile salts, adherence to intestinal epithelial cells, and effective immunomodulatory and anti-inflammatory potential. Furthermore, 240 zebrafish were randomly divided into 4 groups. After 1 week on a basal diet with or without SHY21-2, all zebrafish were exposed to water with or without A. hydrophila AH40 for 12 h; finally, all zebrafish were transferred to freshwater and fed the basal diet for 5 days. The results showed that supplementation with SHY21-2 alleviated the symptoms of zebrafish infected with A. hydrophila, significantly reduced mortality, inhibited intestinal and muscle inflammation, maintained intestinal barrier integrity, and alleviated hepatic oxidative stress responses. Notably, AH40-infection induced variations in microbial diversity and enriched harmful bacteria, such as unclassified-f-Parachlamydiaceae, Rhodococcus, unclassified-f-Microbacteriaceae, and Bosea, whereas supplementation with SHY21-2 reversed this result and significantly increased the abundance of beneficial bacteria, such as Lactiplantibacillus, Leucobacter, and Gemmobacter. In conclusion, these results suggest that SHY21-2 can effectively protect zebrafish against A. hydrophila infection and is an appropriate candidate probiotic for the aquaculture industry.