Intestinal Epithelial Cell Apoptosis Research Articles

Global Transcriptome Analysis Reveals Corresponding Genes and Key Pathways Involved in Oxidative Stress in Mouse Small Intestinal Cells

Abstract Understanding the molecular mechanisms involved in the effects of oxidative stress in humans and animals is important to minimize the damage it causes, leading to various intestinal diseases. Our aim is to study the genes and pathways involved in oxidative stress in the gut using mouse small intestinal epithelial cells (MODE-K) as a model. The MODE-K cell line was divided into two different groups: one group was treated with hydrogen peroxide (H2O2) and the other group was not. To analyze the effects of H2O2 exposure, cell viability, apoptosis rate and reactive oxygen species (ROS) levels were determined. Next, transcriptome sequencing was performed, differentially expressed genes (DEGs) were identified and function annotation was performed, followed by a series of bioinformatics analyses. Real-time PCR was used to confirm the transcriptome data. Our results showed that H2O2-induced oxidative stress significantly increased ROS synthesis and promoted cell apoptosis in mouse small intestinal epithelial cells. During oxidative stress, 1207 DEGs (859 up-regulated, 348 down-regulated) were identified. According to GO analysis, DEGs are annotated into 51 different GO classifications including 22 biological processes, 15 cellular components and 14 molecular functions. In addition, using KEGG, PPI and correlation analysis, the two most significant subnetworks were identified. Ten correlated nodal DEGs of the first subnetwork correspond to MAPK, NF-kappa B and PI3K-AKT signaling pathways, and six correlated DEGs of the second subnetwork are associated with mitochondria. KDM6B was found to link these two subnetworks. The results suggest that oxidative stress affects epithelial growth, metabolism and apoptosis in a mouse model of intestinal cells through signaling pathways such as MAPK and PI3K/AKT/NF-kappa B, and mitochondria-related genes that are interconnected through the PTGS2-KDM6B-MT-ATP6 pathway.

PLK1-activating IFI16-STING-TBK1 pathway induces apoptosis of intestinal epithelial cells in patients with intestinal Behçet's syndrome.

Inflammatory signals from immunological cells may cause damage to intestinal epithelial cells (IECs), resulting in intestinal inflammation and tissue impairment. Interferon-γ-inducible protein 16 (IFI16) was reported to be involved in the pathogenesis of Behçet's syndrome (BS). This study aimed to investigate how inflammatory cytokines released by immunological cells and IFI16 participate in the pathogenesis of intestinal BS. RNA sequencing and real-time quantitative PCR (qPCR) showed that the positive regulation of tumor necrosis factor-α (TNF-α) production in peripheral blood mononuclear cells (PBMCs) of intestinal BS patients may be related to the upregulation of polo like kinase 1 (PLK1) in PBMCs (P = 0.012). The plasma TNF-α protein level in intestinal BS was significantly higher than in healthy controls (HCs; P = 0.009). PBMCs of intestinal BS patients and HCs were co-cultured with human normal IECs (NCM460) to explore the interaction between immunological cells and IECs. Using IFI16 knockdown, PBMC-NCM460 co-culture, TNF-α neutralizing monoclonal antibody (mAb), stimulator of interferon genes (STING) agonist 2'3'-cGAMP, and the PLK1 inhibitor SBE 13 HCL, we found that PLK1 promotes the secretion of TNF-α from PBMCs of intestinal BS patients, which causes overexpression of IFI16 and induces apoptosis of IECs via the STING-TBK1 pathway. The expressions of IFI16, TNF-α, cleaved caspase 3, phosphorylated STING (pSTING) and phosphorylated tank binding kinase 1 (pTBK1) in the intestinal ulcer tissue of BS patients were significantly higher than that of HCs (all P < 0.05). PLK1 in PBMCs of intestinal BS patients increased TNF-α secretion, inducing IEC apoptosis via activation of the IFI16-STING-TBK1 pathway. PLK1 and the IFI16-STING-TBK1 pathway may be new therapeutic targets for intestinal BS.

The artificial sweetener neotame negatively regulates the intestinal epithelium directly through T1R3-signaling and indirectly through pathogenic changes to model gut bacteria.

Recent studies have indicated considerable health risks associated with the consumption of artificial sweeteners. Neotame is a relatively new sweetener in the global market however there is still limited data on the impact of neotame on the intestinal epithelium or the commensal microbiota. In the present study, we use a model of the intestinal epithelium (Caco-2) and microbiota (Escherichia coli and Enterococcus faecalis) to investigate how physiologically-relevant exposure of neotame impacts intestinal epithelial cell function, gut bacterial metabolism and pathogenicity, and gut epithelium-microbiota interactions. Our findings show that neotame causes intestinal epithelial cell apoptosis and death with siRNA knockdown of T1R3 expression significantly attenuating the neotame-induced loss to cell viability. Similarly, neotame exposure results in barrier disruption with enhanced monolayer leak and reduced claudin-3 cell surface expression through a T1R3-dependent pathway. Using the gut bacteria models, E. coli and E. faecalis, neotame significantly increased biofilm formation and metabolites of E. coli, but not E. faecalis, reduced Caco-2 cell viability. In co-culture studies, neotame exposure increased adhesion capacity of E. coli and E. faecalis onto Caco-2 cells and invasion capacity of E. coli. Neotame-induced biofilm formation, E.coli-specific Caco-2 cell death, adhesion and invasion was identified to be meditated through a taste-dependent pathway. Our study identifies novel pathogenic effects of neotame on the intestinal epithelium or bacteria alone, and in co-cultures to mimic the gut microbiome. These findings demonstrate the need to better understand food additives common in the global market and the molecular mechanisms underlying potential negative health impacts.

T-bet Regulates Ion Channels and Transporters and Induces Apoptosis in Intestinal Epithelial Cells.

T-bet, encoded by TBX21, is extensively expressed across various immune cell types, and orchestrates critical functions in their development, survival, and physiological activities. However, the role of T-bet in non-immune compartments, notably the epithelial cells, remains obscure. Herein, a Tet-O-T-bet transgenic mouse strain is generated for doxycycline-inducible T-bet expression in adult animals. Unexpectedly, ubiquitous T-bet overexpression causes acute diarrhea, intestinal damage, and rapid mortality. Cell-type-specific analyses reveal that T-bet-driven pathology is not attributable to its overexpression in CD4+ T cells or myeloid lineages. Instead, inducible T-bet overexpression in the intestinal epithelial cells is the critical determinant of the observed lethal phenotype. Mechanistically, T-bet overexpression modulates ion channel and transporter profiles in gut epithelial cells, triggering profound fluid secretion and subsequent lethal dehydration. Furthermore, ectopic T-bet expression enhances gut epithelial cell apoptosis and markedly suppresses colon cancer development in xenograft models. Collectively, the findings unveil a previously unrecognized role of T-bet in intestinal epithelial cells for inducing apoptosis, diarrhea, and local inflammation, thus implicating its potential as a therapeutic target for the treatment of cancer and inflammatory diseases.

Nutritional strategies to reduce intestinal cell apoptosis by alleviating oxidative stress

Abstract The gut barrier is the first line of defense against harmful substances and pathogens in the intestinal tract. The balance of proliferation and apoptosis of intestinal epithelial cells (IECs) is crucial for maintaining the integrity of the intestinal mucosa and its function. However, oxidative stress and inflammation can cause DNA damage and abnormal apoptosis of the IECs, leading to the disruption of the intestinal epithelial barrier. This, in turn, can directly or indirectly cause various acute and chronic intestinal diseases. In recent years, there has been a growing understanding of the vital role of dietary ingredients in gut health. Studies have shown that certain amino acids, fibers, vitamins, and polyphenols in the diet can protect IECs from excessive apoptosis caused by oxidative stress, and limit intestinal inflammation. This review aims to describe the molecular mechanism of apoptosis and its relationship with intestinal function, and to discuss the modulation of IECs' physiological function, the intestinal epithelial barrier, and gut health by various nutrients. The findings of this review may provide a theoretical basis for the use of nutritional interventions in clinical intestinal disease research and animal production, ultimately leading to improved human and animal intestinal health.

18Beta-Glycyrrhetinic Acid Attenuates H2O2-Induced Oxidative Damage and Apoptosis in Intestinal Epithelial Cells via Activating the PI3K/Akt Signaling Pathway.

Oxidative stress causes gut dysfunction and is a contributing factor in several intestinal disorders. Intestinal epithelial cell survival is essential for maintaining human and animal health under oxidative stress. 18beta-Glycyrrhetinic acid (GA) is known to have multiple beneficial effects, including antioxidant activity; however, the underlying molecular mechanisms have not been well established. Thus, the present study evaluated the therapeutic effects of GA on H2O2-induced oxidative stress in intestinal porcine epithelial cells. The results showed that pretreatment with GA (100 nM for 16 h) significantly increased the levels of several antioxidant enzymes and reduced corresponding intracellular levels of reactive oxidative species and malondialdehyde. GA inhibited cell apoptosis via activating the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling pathway, as confirmed by RNA sequencing. Further analyses demonstrated that GA upregulated the phosphorylation levels of PI3K and Akt and the protein level of B cell lymphoma 2, whereas it downregulated Cytochrome c and tumor suppressor protein p53 levels. Moreover, molecular docking analysis predicted the binding of GA to Vasoactive intestinal peptide receptor 1, a primary membrane receptor, to activate the PI3K/Akt signaling pathway. Collectively, these results revealed that GA protected against H2O2-induced oxidative damage and cell apoptosis via activating the PI3K/Akt signaling pathway, suggesting the potential therapeutic use of GA to alleviate oxidative stress in humans/animals.

Bacillus subtilis alleviates excessive apoptosis of intestinal epithelial cells in intrauterine growth restriction suckling piglets via the members of Bcl-2 and caspase families.

The intestine is a barrier resisting various stress responses. Intrauterine growth restriction (IUGR) can cause the damage of intestinal barrier via destroying the balance of intestinal epithelial cells' proliferation and apoptosis. Bacillus subtilis has been reported to regulate intestinal epithelial cells' proliferation and apoptosis. Thus, the purpose of the current study was to determine if B. subtilis could regulate intestinal epithelial cells' proliferation and apoptosis in intrauterine growth restriction suckling piglets. Compared with normal birth weight group, IUGR group showed greater mean optical density values of Ki-67 positive cells in the ileal crypt (P < 0.05). IUGR resulted in higher ability of proliferation and apoptosis of intestinal epithelial cells, by up-regulation of the mRNA or proteins expression of leucine rich repeat containing G protein coupled receptor 5, Caspase-3, Caspase-7, β-catenin, cyclinD1, B-cell lymphoma-2 associated agonist of cell death, and BCL2 associated X (P < 0.05), and down-regulation of the mRNA or protein expression of B-cell lymphoma-2 and B-cell lymphoma-2-like 1 (P < 0.05). However, B. subtilis supplementation decreased the mRNA or proteins expression of leucine rich repeat containing G protein coupled receptor 5, SPARC related modular calcium binding 2, tumor necrosis factor receptor superfamily member 19, cyclinD1, Caspase-7, β-catenin, B-cell lymphoma-2 associated agonist of cell death, and Caspase-3 (P < 0.05), and increased the mRNA expression of B-cell lymphoma-2 (P < 0.05). IUGR led to excessive apoptosis of intestinal epithelial cells, which induced compensatory proliferation. However, B. subtilis treatment prevented intestinal epithelial cells of IUGR suckling piglets from excessive apoptosis. This article is protected by copyright. All rights reserved.

Naringenin Alleviates Radiation-Induced Intestinal Injury by Inhibiting TRPV6 in Mice.

Naringenin (NAR) possesses unique anti-inflammatory, antiapoptosis effects and various bioactivities; however, its role against radiation-induced intestinal injury (RIII) remains unclear. This study aims to investigate whether NAR has protective effects against radiation-induced intestinal injury and the underlying mechanisms. C57BL/6J mice are exposed to a single dose of 13Gy X-ray total abdominal irradiation (TAI), then gavaged with NAR for 7 days. NAR treatment prolongs the survival rate, protects crypts and villi from damage, alleviates the level of radiation-induced inflammation, and mitigates intestinal barrier damage in the irradiated mice. Additionally, NAR reduces immune cell infiltration and intestinal epithelial cell apoptosis. NAR also shows radioprotective effects in human colon cancer cells (HCT116) and human intestinal epithelial cells (NCM460). It reduces cell damage by reducing intracellular calcium ion levels and reactive oxygen species (ROS) levels. NAR-mediated radioprotection is associated with the downregulation of transient receptor potential vanilloid 6 (TRPV6), and inhibition of apoptosis pathway. Notably, treatment with NAR fails to further increase the protective effects of the TRPV6 inhibitor 2-APB, indicating that TRPV6 inhibition is essential for NAR activity. NAR inhibits the apoptosis pathway by downregulating TRPV6 and reducing calcium ion level, thereby alleviating RIII. Therefore, NAR is a promising therapeutic drug for RIII.

Intestinal Piezo1 aggravates intestinal barrier dysfunction during sepsis by mediating Ca2+ influx

IntroductionIntestinal barrier dysfunction is a pivotal factor in sepsis progression. The mechanosensitive ion channel Piezo1 is associated with barrier function; however, its role in sepsis-induced intestinal barrier dysfunction remains poorly understood.MethodsThe application of cecal ligation and puncture (CLP) modeling was performed on both mice of the wild-type (WT) variety and those with Villin-Piezo1flox/flox genetic makeup to assess the barrier function using in vivo FITC-dextran permeability measurements and immunofluorescence microscopy analysis of tight junctions (TJs) and apoptosis levels. In vitro, Caco-2 monolayers were subjected to TNF-α incubation. Moreover, to modulate Piezo1 activation, GsMTx4 was applied to inhibit Piezo1 activation. The barrier function, intracellular calcium levels, and mitochondrial function were monitored using calcium imaging and immunofluorescence techniques.ResultsIn the intestinal tissues of CLP-induced septic mice, Piezo1 protein levels were notably elevated compared with those in normal mice. Piezo1 has been implicated in the sepsis-mediated disruption of TJs, apoptosis of intestinal epithelial cells, elevated intestinal mucosal permeability, and systemic inflammation in WT mice, whereas these effects were absent in Villin-Piezo1flox/flox CLP mice. In Caco-2 cells, TNF-α prompted calcium influx, an effect reversed by GsMTx4 treatment. Elevated calcium concentrations are correlated with increased accumulation of reactive oxygen species, diminished mitochondrial membrane potential, and TJ disruption.ConclusionsThus, Piezo1 is a potential contributor to sepsis-induced intestinal barrier dysfunction, influencing apoptosis and TJ modification through calcium influx-mediated mitochondrial dysfunction.

Effects of feeding chicken egg yolk antibodies on intestinal cell apoptosis, oxidative stress and microbial flora of tilapia (Oreochromis niloticus) infected with Streptococcus agalactiae

Streptococcosis, the most common bacterial disease of fish in recent years, is highly infectious and lethal, and has become an important factor hindering the healthy and sustainable development of aquaculture. Chicken egg yolk antibody (IgY) has the advantages of high antigen specificity, inexpensive and easy to obtain, simple preparation, no toxic side effects, and in line with animal welfare, which is a green and safe alternative to antibiotics. In this study, the potential of specific IgY in the treatment of gastrointestinal pathogens was explored by observing the effects of specific IgY on intestinal flora, pathological tissue, apoptosis, oxidative stress, and inflammatory response of tilapia. We used the specific IgY prepared in the early stage to feed tilapia for 10 days, and then the tilapia was challenged with Streptococcus agalactiae. The results showed that feeding IgY before challenge had a small effect on the intestinal flora, and after challenge specific IgY decreased the proportion of Streptococcus and increased the diversity of the intestinal flora; in histopathology, specific IgY decreased tissue damage and maintained the integrity of tissue structure.Further study found that specific IgY can reduce intestinal epithelial cell apoptosis and reduce caspase activity; at the same time, the content of MDA was decreased, and the activities of SOD, CAT, GSH-Px and GR were increased. In addition, specific IgY can down-regulate the expression levels of IL-8 and TNF-α genes and up-regulate the expression levels of IL-10 and TGF-β. The results of this study showed that specific IgY could improve the intestinal flora of tilapia infected with Streptococcus agalactiae, reduce intestinal cell apoptosis, oxidative stress injury and inflammatory response, thereby reducing tissue damage and protecting the health of tilapia. Overall, specific IgY can be further explored as a potential antibiotic alternative for gastrointestinal pathogen infections.

Effects of Hericium erinaceus polysaccharide in porcine IPEC-J2 intestinal epithelial cells against apoptosis induced by oxidative stress

This study was intended to investigate whether Hericium erinaceus polysaccharides (HEP) prevent oxidative stress and apoptosis of intestinal porcine epithelial cells from jejunum (IPEC-J2 cells) induced by hydrogen peroxide (H2O2). Crude HEP were extracted and purified by chromatography. The ultraviolet and infrared spectra and monosaccharide composition of HEP were analyzed. Reactive oxygen species (ROS) generation was quantified by flow cytometry method, and lactate dehydrogenase (LDH) and malondialdehyde (MDA) production were determined by TBARS. Also, apoptosis was analyzed by flow cytometry method and the apoptosis-related regulatory molecules were determined by microplate or western blotting method. Our results showed that pretreatment of IPEC-J2 cells with HEP significantly scavenged ROS and reduced LDH and MDA production. HEP also reduced apoptosis and kept polarity of the mitochondrial membrane potential. Moreover, HEP increased the content of caspase-3 and PARP, and protein expression of Bcl-2, while inhibited Bax and Bad and reduced the content of caspase-9 and release of CytC. Meanwhile, HEP inhibited the protein expression of TNFR1, FAS, and FASL, and decreased the content of caspase-8. The results indicated that HEP had a protective effect against oxidative stress in IPEC-J2 cells and the underlying mechanism was reducing apoptosis via mitochondrial and death receptor pathways.

Sophoricoside improved Crohn's disease-like colitis by inhibiting intestinal epithelial cell apoptosis through PI3K/AKT signaling

Background and aimsIncreased apoptosis of intestinal epithelial cells (IECs) is a significant cause of intestinal barrier dysfunction in Crohn’s disease (CD). Sophoricoside (SOP) is an isoflavone glycoside known for its anti-apoptotic properties. The aim of this study was to investigate the effects of SOP on mice with CD-like colitis and to understand the underlying mechanisms. MethodsMice treated with 2,4,6-trinitrobenzene sulfonic acid (TNBS) were used to examine the therapeutic effect of SOP on CD-like colitis and intestinal barrier damage. To further explore SOP's impact on IECs apoptosis and intestinal barrier protection, an in vitro colonic organoid apoptosis model induced by TNF-α was utilized. Network pharmacology was employed to predict the relevant pathways and molecular processes associated with SOP in the treatment of CD. ResultsTreatment with SOP significantly improved colitis symptoms in TNBS mice, as demonstrated by reductions in the Disease Activity Index (DAI), weight loss, colon shortening, macroscopic scores, colonic tissue inflammatory scores, and the expression of pro-inflammatory factors. Our experiments confirmed that SOP protects the intestinal barrier by counteracting IECs apoptosis. Additionally, this study established that SOP reduced IECs apoptosis by inhibiting the PI3K/AKT signaling pathway. ConclusionsSOP can reduce IECs apoptosis through the inhibition of the PI3K/AKT signaling pathway, thereby protecting the intestinal barrier. This study is the first to illustrate how SOP ameliorates colitis and protects the intestinal barrier, suggesting SOP has potential clinical application in treating CD.

Hypoxia-inducible factor 1α inhibits heat stress-induced pig intestinal epithelial cell apoptosis through eif2α/ATF4/CHOP signaling

Unstoppable global warming and increased frequency of extreme heat leads to human and animals easier to suffer from heat stress (HS), with gastrointestinal abnormalities as one of the initial clinical symptoms. HS induces intestinal mucosal damage owing to intestinal hypoxia and hyperthermia. Hypoxia-inducible factor 1α (HIF-1α) activates numerous genes to mediate cell hypoxic responses; however, its role in HS-treated intestinal mucosa is unknown. This work aimed to explore HIF-1α function and regulatory mechanisms in HS-treated pig intestines. We assigned 10 pigs to control and moderate HS groups. Physical signs, stress, and antioxidant levels were detected, and the intestines were harvested after 72 h of HS treatment to study histological changes and HIF-1α, heat shock protein 90 (HSP90), and prolyl-4-hydroxylase 2 (PHD-2) expression. In addition, porcine intestinal columnar epithelial cells (IPEC-J2) underwent HS treatment (42 °C, 5 % O2) to further explore the functions and regulatory mechanism of HIF-1α. The results of histological examination revealed HS caused intestinal villi damage and increased apoptotic epithelial cell; the expression of HIF-1α and HSP90 increased while PHD-2 showed and opposite trend. Transcriptome sequencing analysis revealed that HS activated HIF-1 signaling. To further explore the role of HIF-1α on HS induced IPEC-J2 apoptosis, the HIF-1α was interfered and overexpression respectively, and the result confirmed that HIF-1α could inhibited cell apoptosis under HS. Furthermore, HS-induced apoptosis depends on eukaryotic initiation factor 2 alpha (eif2α)/activating transcription factor 4 (ATF4)/CCAAT-enhancer-binding protein homologous protein (CHOP) pathway, and HIF-1α can inhibit this pathway to alleviate IPEC-J2 cell apoptosis. In conclusion, this study suggests that HS can promote intestinal epithelial cell apoptosis and cause pig intestinal mucosal barrier damage; the HIF-1α can alleviate cell apoptosis by inhibiting eif2α/ATF4/CHOP signaling. These results indicate that HIF-1α plays a protective role in HS, and offers a potential target for HS prevention and mitigation.

Protective effect of crocin on peroxidation-induced oxidative stress and apoptosis in IPEC-J2 cells.

The antioxidant properties of crocin are attracting interest, yet the underlying mechanisms by which crocin mitigates oxidative stress-induced intestinal damage have not been determined. This study aimed to elucidate the effects of crocin on oxidative stress, apoptosis, and intestinal epithelial injury in intestinal epithelial cells (IPEC-J2). Using an H2 O2 -induced oxidative stress model in IPEC-J2 cells, crocin was added to assess its effects. Cell viability and apoptosis were evaluated using methyl thiazolyl tetrazolium assays and flow cytometry. Additionally, oxidative stress markers, such as superoxide dismutase (SOD), catalase (CAT), reactive oxygen species (ROS), and malondialdehyde (MDA), were quantified. We investigated, in which cell oxidation and apoptosis were measured at the gene and protein levels and employed transcriptome analysis to probe the mechanism of action and validate relevant pathways. The results showed that crocin ameliorates H2 O2 -induced oxidative stress by reducing ROS and MDA levels and by countering the reductions in CAT, total antioxidant capacity, and SOD. Crocin also attenuates the upregulation of key targets in the Nrf2 pathway. Furthermore, it effectively mitigated IPEC-J2 cell apoptosis caused by oxidative stress, as evidenced by changes in cell cycle factor expression, apoptosis rate, mitochondrial membrane potential, and apoptosis pathway activity. In addition, crocin preserves the integrity of the intestinal barrier by protecting tight junction proteins against oxidative stress. Transcriptome sequencing analysis suggested that the mitochondrial pathway may be a crucial mechanism through which crocin exerts its protective effects. In summary, crocin decreases oxidative stress molecule formation, inhibits Nrf2 pathway activity, prevents apoptosis-induced damage, enhances oxidative stress resistance in IPEC-J2 cells, and maintains redox balance in the pig intestine.

4-Phenylbutyric Acid Attenuates Soybean Glycinin/β-Conglycinin-Induced IPEC-J2 Cells Apoptosis by Regulating the Mitochondria-Associated Endoplasmic Reticulum Membrane and NLRP-3.

Glycinin (11S) and β-conglycinin (7S) from soybean (glycine max) cause diarrhea and intestinal barrier damage in young animals. Understanding the mechanisms underlying the damage caused by 7S and 11S, it is vital to develop strategies to eliminate allergenicity. Consequently, we investigated 7S/11S-mediated apoptosis in porcine intestinal epithelial (IPEC-J2) cells. IPEC-J2 cells suffered endoplasmic reticulum stress (ERS) in response to 7S and 11S, activating protein kinase RNA-like ER kinase, activating transcription factor 6, C/EBP homologous protein, and inositol-requiring enzyme 1 alpha. 4-Phenylbutyric acid (4-PBA) treatment alleviated ERS; reduced the NLR family pyrin domain containing 3, interleukin-1β, and interleukin-18 levels; inhibited apoptosis; increased mitofusin 2 expression; and mitigated Ca2+ overload and mitochondria-associated ER membrane (MAM) dysfunction, thereby ameliorating IPEC-J2 injury. We demonstrated the pivotal role of ERS in MAM dysfunction and 7S- and 11S-mediated apoptosis, providing insights into 7S- and 11S-mediated intestinal barrier injury prevention and treatment.

MiR-375-3p targets YWHAB to attenuate intestine injury in neonatal necrotizing enterocolitis.

Necrotizing enterocolitis (NEC) is a significant contributor to neonatal mortality. This study aimed to investigate the role of high levels of miR-375-3p in breast milk in the development of NEC and elucidate its mechanism. Differential expression of miR-375-3p in the intestines of breast-fed and formula-fed mice was confirmed using real-time polymerase chain reaction (RT-PCR). NEC mice models were established, and intestinal injury was assessed using HE staining. RT-PCR and Western blot were conducted to examine the expression of miR-375-3p, tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein β (YWHAB), as well as the inflammatory in IEC-6 cells, and intestinal tissues obtained from NEC mice and patients. Flow cytometry and cell counting kit-8 (CCK-8) were employed to elucidate the impact of miR-375-3p and YWHAB on cell apoptosis and proliferation. Breastfeeding increases miR-375-3p expression in the intestines. The expression of miR-375-3p in NEC intestinal tissues exhibited a significant decrease compared to the healthy group. Additionally, the expression of interleukin-6 (IL-6), interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α) was higher in the NEC group compared to the control group. Down-regulation of miR-375-3p inhibited IEC-6 cell proliferation, increased apoptosis, and elevated secretion of inflammatory factors. Bioinformatics revealed that YWHAB may be a target of miR-375-3p. RT-PCR and Western blot indicated a down-regulation of YWHAB expression in intestines of NEC patients and mice. Furthermore, YWHAB was found to be positively connected with miR-375-3p. Knockdown miR-375-3p down-regulated YWHAB expression in cells. Inhibition of YWHAB exhibited similar effects to miR-375-3p in IEC-6 cells. YWHAB plasmid partially reverse cellular functional impairment induced by miR-375-3p knockdown. Breastfeeding elevated miR-375-3p expression in intestines in neonatal mice. MiR-375-3p leads to a decrease in apoptosis of intestinal epithelial cells, an increase in cell proliferation, and a concomitant reduction in the expression of inflammatory factors partly through targeting YWHAB.

2'-Hydroxycinnamaldehyde Alleviates Intestinal Inflammation by Attenuating Intestinal Mucosal Barrier Damage Via Directly Inhibiting STAT3.

The currently available clinical therapeutic drugs for ulcerative colitis (UC) are considered inadequate owing to certain limitations. There have been reports on the anti-inflammatory effects of 2'-hydroxycinnamaldehyde (HCA). However, whether HCA can improve UC is still unclear. Here, we aimed to investigate the pharmacological effects of HCA on UC and its underlying molecular mechanisms. The pharmacological effects of HCA were comprehensively investigated in 2 experimental setups: mice with dextran sulfate sodium (DSS)-induced colitis and lipopolysaccharide (LPS)-treated fetal human colon (FHC) cells. Furthermore, the interaction between HCA and signal transducer and activator of transcription 3 (STAT3) was investigated using molecular docking. The FHC cells with STAT3 knockdown or overexpression and mice with intestinal epithelium-specific STAT3 deletion (STAT3ΔIEC) were used to evaluate whether STAT3 mediated the pharmacological effects of HCA. 2'-Hydroxycinnamaldehyde attenuated dysregulated expression of inflammatory cytokines in a dose-dependent manner while increasing the expression of tight junction proteins, reducing the apoptosis of intestinal epithelial cells, and effectively alleviating inflammation both in vivo and in vitro. 2'-Hydroxycinnamaldehyde bound directly to STAT3 and inhibited its activation. The modulation of STAT3 activation levels due to STAT3 knockdown or overexpression influenced the mitigating effects of HCA on colitis. Further analysis indicated that the remission effect of HCA was not observed in STAT3ΔIEC mice, indicating that STAT3 mediated the anti-inflammatory effects of HCA. We present a novel finding that HCA reduces colitis severity by attenuating intestinal mucosal barrier damage via STAT3. This discovery holds promise as a potential new strategy to alleviate UC.

Effects of L-Leu-L-Leu peptide on growth, proliferation, and apoptosis in broiler intestinal epithelial cells

Small peptides are nutrients and bioactive molecules that have dual regulatory effects on nutrition and physiology. They are of great significance for maintaining the intestinal health and production performance of broilers. We here cultured the primary small intestinal epithelial cells (IEC) of chicken in a medium containing L-Leu (Leu) and L-Leu-L-Leu (Leu-Leu) for 24 h. The untreated cells were considered as the control group. The growth, proliferation, and apoptosis of IEC were examined. By combining RNA-seq and label-free sequencing technology, candidate genes, proteins, and pathways related to the growth, proliferation, and apoptosis of IEC were screened. Immunofluorescence detection revealed that the purity of the isolated primary IEC was >90%. The Leu-Leu group significantly promoted IEC growth and proliferation and significantly inhibited IEC apoptosis, and the effect was better than those of the Leu and control groups. Using transcriptome sequencing, four candidate genes, CCL20, IL8L1, IL8, and IL6, were screened in the Leu group, and one candidate gene, IL8, was screened in the Leu-Leu group. Two candidate genes, IL6 and RGN, were screened in the Leu-Leu group compared with the Leu group. Non-quantitative proteomic marker sequencing results revealed that through the screening of candidate proteins and pathways, found one growth-related candidate protein PGM3 and three proliferation-related candidate proteins RPS17, RPS11, and RPL23, and two apoptosis-related candidate proteins GPX4 and PDPK1 were found in the Leu-Leu group compared with Leu group. In short, Leu-Leu could promote IEC growth and proliferation and inhibit IEC apoptosis. On combining transcriptome and proteome sequencing technologies, multiple immune- and energy-related regulatory signal pathways were found to be related to IEC growth, proliferation, and apoptosis. Three candidate genes of IL8, IL6, and RGN were identified, and five candidate proteins of RPS17, RPS11, RPL23, GPX4, and PDPK1 were involved in IEC growth, proliferation, and apoptosis. The results provide valuable data for preliminarily elucidating small peptide-mediated IEC regulation pathways, improving the small peptide nutrition theoretical system, and establishing small peptide nutrition regulation technology.

Peiminine alleviate coliti-like phenotype in mice induced by lead exposure

ABSTRACT The deleterious impact of lead (Pb) pollution on human health is evident in both domestic and occupational settings, provoking an inflammatory response across multiple tissue, limited attention has been devoted to its adverse effects on colitis and the underlying mechanisms. Peiminine (PMI) has been recognized for its anti-inflammatory properties, yet its specific anti-inflammatory effects in lead-induced colitis models remain elusive. Through the establishment of both in vivo and in vitro lead exposure models, suggests that lead exposure can induce colitis and that PMI regulates lead exposure-induced colitis by inhibiting the NF-kB signaling pathway, and alleviates the ability of lead to apoptosis and inflammation levels in intestinal epithelial cells. Consequently, these results present a promising avenue for further exploration of the molecular mechanisms underlying lead-induced colitis, evaluation of the associated risks linked to lead exposure, and the development of therapeutic interventions for colitis resulting from lead exposure.

Si-based agent alleviated small bowel ischemia–reperfusion injury through antioxidant effects

The progression of small bowel ischemia–reperfusion (IR) injury causes cells in the intestinal tract to undergo necrosis, necessitating surgical resection, which may result in loss of intestinal function. Therefore, developing therapeutic agents that can prevent IR injury at early stages and suppress its progression is imperative. As IR injury may be closely related to oxidative stress, antioxidants can be effective therapeutic agents. Our silicon (Si)-based agent, an antioxidant, generated a large amount of hydrogen in the intestinal tract for a prolonged period after oral administration. As it has been effective for ulcerative colitis, renal failure, and IR injury during skin flap transplantation, it could be effective for small intestinal IR injury. Herein, we investigated the efficacy of an Si-based agent in a mouse model of small intestinal IR injury. The Si-based agent suppressed the apoptosis of small intestinal epithelial cells by reducing the oxidative stress induced by IR injury. In addition, the thickness of the mucosal layer in the small intestine of the Si-based agent-administered group was significantly higher than that in the untreated group, revealing that Si-based agent is effective against small intestinal IR injuries. In the future, Si-based agents may improve the success rate of small intestine transplantation.