Intestinal Ischemia-reperfusion Injury Research Articles

Plasma resuscitation improves and restores intestinal microcirculatory physiology following haemorrhagic shock.

Intestinal ischaemia-reperfusion injury following resuscitated haemorrhagic shock (HS) leads to endothelial and microcirculatory dysfunction and intestinal barrier breakdown. Although vascular smooth muscle machinery remains intact, microvascular vasoconstriction occurs secondary to endothelial cell dysfunction, resulting in further ischaemia and organ injury. Resuscitation with fresh frozen plasma (FFP) improves blood flow, stabilizes the endothelial glycocalyx and alleviates organ injury. We postulate these improvements correlate with decreased tissue CO2 concentrations, improved microvascular oxygenation and attenuation of intestinal microvascular endothelial dysfunction. Male Sprague-Dawley rats were randomly assigned to groups (n = 8/group): (1) sham, (2) HS (40% mean arterial blood pressure [MAP], 60 min) + crystalloid resuscitation (CR) (shed blood saline) and (3) HS + FFP (shed blood + FFP). MAP, heart rate (HR), ileal perfusion, pO2 and pCO2 were measured at intervals until 4 h post-resuscitation (post-RES). At 4 h post-RES, the ileum was rinsed in situ with Krebs solution. Topical acetylcholine and then nitroprusside were applied for 10 min each. Serum was obtained, and after euthanasia, tissues were harvested and snap-frozen in liquid N2 and stored at -80°C. FFP resuscitation resulted in sustained ileal perfusion as well as rapid sustained return to baseline microvascular pO2 and pCO2 values when compared to CR (p < 0.05). Endothelial function was preserved relative to sham in the FFP group but not in the CR group (p < 0.05). FFP-based resuscitation improves intestinal perfusion immediately following resuscitation, which correlates with improved tissue oxygenation and decreased tissue CO2 levels. CR resulted in significant damage to endothelial vasodilation response to acetylcholine, while FFP preserved this function.

Stem cell Derived Extracellular Vesicles to Alleviate ischemia-reperfusion Injury of Transplantable Organs. A Systematic Review.

The possible beneficial effects of stem cell-derived EV on ischemia-reperfusion injury (IRI) in organ transplantation have been frequently investigated; however, the source of EV, as well as the methods of isolation and administration vary widely. We conducted a systematic review to summarize current pre-clinical evidence on stem cell-derived EV therapy for IRI of transplantable organs. PubMed, Embase and Web of Science were searched from inception until August 19th, 2022, for studies on stem cell-derived EV therapy for IRI after heart, kidney, liver, pancreas, lung and intestine transplantation. The Systematic Review Center for Laboratory animal Experiments (SYRCLE) guidelines were followed to assess potential risk of bias. The search yielded 4153 unique articles, of which 96 were retained. We identified 32 studies on cardiac IRI, 38 studies on renal IRI, 21 studies on liver IRI, four studies on lung IRI and one study on intestinal IRI. Most studies used rodent models of transient ischemic injury followed by in situ reperfusion. In all studies, EV therapy was associated with improved outcome albeit to a variable degree. EV-therapy reduced organ injury and improved function while displaying anti-inflammatory-, immunomodulatory- and pro-regenerative properties. A multitude of animal studies support the potential of stem cell-derived EV-therapy to alleviate IRI after solid organ transplantation but suffer from low reporting quality and wide methodological variability. Future studies should focus on determining optimal stem cell source, dosage, and timing of treatment, as well as long-term efficacy in transplant models.

Transcription factor Krüppel-like factor 4 upregulated G protein-coupled receptor 30 alleviates intestinal inflammation and apoptosis, and protects intestinal integrity from intestinal ischemia-reperfusion injury.

Intestinal ischemia/reperfusion (I/R) injury is a common clinical event occurring during multiple clinical pathological processes. Here, we designed this paper to discuss the role of G protein-coupled receptor 30 (GPR30) playing in intestinal I/R injury. An oxygen-glucose deprivation/reoxygenation (OGD/R) cell model was established to simulate the pathological process of I/R injury. With the application of enzyme-linked immunosorbent assay, TUNEL, and transepithelial electrical resistance (TEER) assays, the levels of inflammatory cytokines, cell apoptosis, and intestinal integrity were estimated. The corresponding proteins were estimated by applying western blot. Immunofluorescence was conducted to examine N-terminal Gasdermin D (GSDMD-N) expression. The interplay between KLF4 and GPR30 was demonstrated by dual-luciferase reporter assay and chromatin immunoprecipitation. The results showed that GPR30 was downregulated in Caco-2 cells exposed to OGD/R. GPR30 overexpression reduced the production of TNF-α, IL-6, IL-1β, and IL-18, the TUNEL-positive cells, as well as the contents of p-p65, Cox-2, Inos, Bax, and cleaved-PARP, but elevated the expression of Bcl-2 in OGD/R-induced Caco-2 cells. In addition, OGD/R-induced the reduction of TEER value and reduced expression of tight junction proteins in Caco-2 cells, which was partially restored by GPR30 overexpression. Furthermore, GPR30 suppressed nod-like receptor pyrin 3inflammasome and GSDMD-N expression. It was evidenced that Krüppel-like factor 4 (KLF4) could directly bind to GPR30 promoter and positively regulate GPR30 expression. The regulation of GPR30 overexpression above was weakened by KLF4 knockdown. Collectively, our findings suggested that KLF4 could transcriptionally upregulate GPR30, and GPR30 prevented intestine I/R injury by inhibiting inflammation and apoptosis, and maintaining intestinal integrity that provides potential targets for mitigating the I/R injury.

Intravenous Polyethylene Glycol Alleviates Intestinal Ischemia-Reperfusion Injury in a Rodent Model

Intestinal ischemia-reperfusion injury (IRI) is a common clinical entity, and its outcome is unpredictable due to the triad of inflammation, increased permeability and bacterial translocation. Polyethylene glycol (PEG) is a polyether compound that is extensively used in pharmacology as an excipient in various products. More recently, this class of products have shown to have potent anti-inflammatory, anti-apoptotic, immunosuppressive and cell-membrane-stabilizing properties. However, its effects on the outcome after intestinal IRI have not yet been investigated. We hypothesized that PEG administration would reduce the effects of intestinal IRI in rodents. In a previously described rat model of severe IRI (45 min of ischemia followed by 60 min of reperfusion), we evaluated the effect of IV PEG administration at different doses (50 and 100 mg/kg) before and after the onset of ischemia. In comparison to control animals, PEG administration stabilized the endothelial glycocalyx, leading to reduced reperfusion edema, bacterial translocation and inflammatory reaction as well as improved 7-day survival. These effects were seen both in a pretreatment and in a treatment setting. The fact that this product is readily available and safe should encourage further clinical investigations in settings of intestinal IRI, organ preservation and transplantation.

Succinate pretreatment attenuates intestinal ischemia-reperfusion injury by inhibiting necroptosis and inflammation via upregulating Klf4

Intestinal ischemia-reperfusion (I/R) injury is a common pathophysiological process in various diseases, and the disruption of the intestinal barrier composed of tight junction proteins is the initiating factor, which then leads to a large number of bacteria and endotoxins in the intestine into the bloodstream causing stress and distant organ damage. The release of inflammatory mediators and abnormal programmed death of intestinal epithelial cells are important factors of intestinal barrier damage. Succinate is an intermediate product of the tricarboxylic acid cycle with anti-inflammatory and pro-angiogenic activities, but its role in the maintenance of intestinal barrier homeostasis after I/R has not been fully elucidated. In this study, we explored the effect of succinate on intestinal ischemia-reperfusion injury and the possible mechanism of its role by flow cytometry, western blotting, real-time quantitative PCR and immunostaining. The results of pretreatment with succinate in the mouse intestinal I/R model and IEC-6 cells hypoxia-reoxygenation (H/R) model revealed a reduction in tissue damage, necroptosis and associated inflammation due to ischemia-reperfusion. Furthermore, it was found that the protective effect of succinate pretreatment may be associated with the transcriptional upregulation of the inflammatory protein KLF4 and the protective effect of intestinal barrier of succinate was diminished after inhibition of KLF4. Thus, our results suggest that succinate can exert a protective effect in intestinal ischemia-reperfusion injury through upregulation of KLF4 and also demonstrate the potential therapeutic value of succinate pretreatment in acute I/R injury of the intestine.

Effect of Gallic Acid on Distant Organ Stomach in Intestinal Ischemia Reperfusion Injury

Aim: To examine the effects of gallic acid (GA) in the stomach in rats undergoing intestinal ischemia/reperfusion (IR) with Beclin -1 immunostaining.&#x0D; Material-Metod: 24 male Wistar albino rats were divided into control, IR and IR+GA groups. For the IR protocol, 60 minutes of ischemia and reperfusion were applied. The small intestines of the rats in the control group were removed by laparotomy and the abdomen was closed without applying anything else. Ischemia and reperfusion was applied to the superior mesenteric artery (SMA) for 60 minutes with a clamp in rats in the IR group. The blood flow was stopped with a clamp on the SMA of the rats in the IR+GA group and ischemia was applied for 60 minutes. 50 mg/kg gallic acid was given intraperitoneally to the animals, 60 minutes of reperfusion was performed, and the abdomen was closed. The stomach tissues were placed in paraffin blocks after routine histological follow-ups. Five micrometer-thick sections were taken from the paraffin blocks and stained with Hematoxylin-eosin and Beclin-1 immunostaining.&#x0D; Results: In the IR group, degeneration of gastric folds, apoptosis of epithelial cells and degeneration of lamina muscularis were observed. In the IR + GA group, gastric folds improved, but cell infiltration in the lamina propria and degeneration in the muscular layer were observed. Beclin-1 expression was positively observed in the surface epithelial cells and gastric glands in the control group. In the IR group, it was observed that the gastric folds were positive on the surface cells and negative in the submucosa, while in the IR + GA group, it was intensely expressed in the gastric epithelium and gastric glands.&#x0D; Conclusion: By increasing the expression of beclin-1, GA treatment induced autophagy in gastric mucosal cells, triggered the destruction of damaged cells and provided restoration of the mucosal layer.&#x0D; Keywords: Beclin-1, gallic acid, apoptosis

6-Shogaol from Dried Ginger Protects against Intestinal Ischemia/Reperfusion by Inhibiting Cell Apoptosis via the BDNF/TrkB/PI3K/AKT Pathway.

Intestinal ischemia-reperfusion (II/R) injury is a common pathological process with high morbidity and mortality. Effective prevention and treatment therapies for II/R are clinically necessary. 6-Shogaol (6-SG), the main active ingredient in dried ginger, behaviors multiple biological activities, including anti-inflammation, antioxidation, and anti-apoptosis. This study aims to elucidate the protective effects and mechanism of 6-SG against II/R-induced injury. Sprague-Dawley rats are pre-treated orally with 6-SG and subjected to II/R injury by clamping superior mesenteric artery for 1h and reperfusion for 2h. Caco-2 cells are challenged by hypoxia/reoxygenation to mimic II/R in vitro. 6-SG pre-treatment protects against II/R injury by reducing intestinal morphological damage and intestinal barrier injury via inhibiting cell apoptosis. Network pharmacology and molecular docking analyses revealthat 6-SG has a high affinity with brain-derived neurotrophic factor (BDNF) formed homodimer or heterodimer with NT4 instead of the monomer, and thus the dimer configuration is stabilized, activating BDNF/TrkB/PI3K/AKT signaling pathway and inhibiting II/R-induced cell apoptosis. The outcome is further validated both in vivo and in vitro. 6-Shogaol protects against II/R injury by inhibiting cell apoptosis through the BDNF/TrkB/PI3K/AKT pathway. This study offers a new understanding of the protection mechanism of 6-SG against II/R-induced injury.

Naringin protects against inflammation and apoptosis induced by intestinal ischemia-reperfusion injury through deactivation of cGAS-STING signaling pathway.

Effective amelioration of ischemia/reperfusion (I/R)-induced intestinal injury and revealing its mechanisms remain the challenges in both preclinic and clinic. Potential mechanisms of naringin in ameliorating I/R-induced intestinal injury remain unknown. Based on pre-experiments, I/R-injured rat intestine in vivo and hypoxia-reoxygenation (H/R)-injured IEC-6 cells in vitro were used to verify that naringin-alleviated I/R-induced intestinal injury was mediated via deactivating cGAS-STING signaling pathway. Naringin improved intestinal damage using hematoxylin and eosin staining and decreased alanine aminotransferase and aspartate aminotransferase contents in plasma. Naringin decreased inflammation characterized by reducing IL-6, IL-1β, TNF-α, and IFN-β contents in both plasma and IEC-6 cells. Naringin mitigated oxidative stress via recovering superoxide dismutase, glutathione, and malondialdehyde levels in the I/R-injured intestine. Naringin reduced the expression of apoptotic proteins, including Bax, caspase-3, and Bcl-2, and reduced terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling-positive cells both in vivo and in vitro, and decreased Hoechst 33342 signals in vitro. cGAS, STING, p-TBK1, p-IRF3, and NF-κB expressions were up-regulated both in vivo and in vitro respectively and the up-regulated indexes were reversed by naringin. Transfection of cGAS-siRNA and cGAS-cDNA significantly down-regulated and up-regulated cGAS-STING signaling-related protein expressions, respectively, and partially weakened naringin-induced amelioration on these indexes, suggesting that deactivation of cGAS-STING signaling is the crucial target for naringin-induced amelioration on I/R-injured intestine.

Profiles of lipid, protein and microRNA expression in exosomes derived from intestinal epithelial cells after ischemia-reperfusion injury in a cellular hypoxia model.

Intestinal ischemia-reperfusion injury leads to proinflammatory responses via gut-derived mediators, and accumulating evidence suggests that exosomes secreted by intestinal epithelial cells are involved in the development of systemic inflammation. Studies have reported changes in protein, lipid, and microRNA (miRNA) expression; however, considering the different experimental conditions, information on the relationships among these biomolecules remains insufficient. The aim of this study was to elucidate the multiple changes that simultaneously occur in exosomes after ischemic stimulation. Here, differentiated human intestinal Caco-2 cells were exposed to 95% air (normoxia group) or 5% O2 (hypoxia group) for 6 h. Cells in each group were subsequently incubated for 24 h in an atmosphere of 5% CO2 plus 95% air. The conditioned medium of each group was collected for isolating intestinal epithelial cell-derived exosomes. Together with proteome analyses, lipid analyses, and miRNA quantification, biological functional assays were performed using monocytic NF-κB reporter cells. Lipid metabolism-related protein expression was upregulated, miRNA levels were slightly altered, and unsaturated fatty acid-containing lysophosphatidylcholine concentration increased after hypoxia and reoxygenation injury; this suggested that the changes in exosomal components associated with ischemia-reperfusion injury activates inflammation, including the NF-κB pathway. This study elucidated the multiple changes that co-occur in exosomes after ischemic stimulation and partially clarified the mechanism underlying exosome-mediated inflammation after intestinal ischemic recanalization.

Rhubarb Peony Decoction Downregulates the Expression of c-Fos after Intestinal Epithelial Cells Hypoxia-reoxygenation Injury.

Intestinal ischemia-reperfusion (I/R) injury occurs in several clinical situations and after intestinal transplantation. This study aimed to examine the role of rhubarb peony decoction (RPD) in intestinal I/R injury. Different concentrations of RPD were set to treat IEC-6 and Caco-2 cells. Cell proliferation and apoptosis were measured by CCK-8 and flow cytometry assays. High-throughput transcriptome sequencing was performed on IEC-6 cells treated with hypoxia-reoxygenation (HR) or HR and RPD. RPD treatment significantly promoted the proliferation of IEC-6 and Caco-2 cells and inhibited apoptosis. Sequencing results identified 109 significantly up-regulated genes and 36 significantly down-regulated genes in the RPD group. In addition, the results of western blot suggested that HR induced the expression of c-Fos, and the treatment of RPD prevented the HR-induced c- Fos expression. Importantly, knockdown of c-Fos rescued the HR-inhibited cell proliferation and HR-induced apoptosis. In conclusion, RPD was beneficial in protecting the survival of intestinal epithelial cells under HR stress. Furthermore, the increase in c-Fos expression after HR stress was closely related to the proliferation and apoptosis of intestinal epithelial cells.

EFFECTS OF MESENCHYMAL STEM CELLS ON POSTRESUSCITATION RENAL AND INTESTINAL INJURIES IN A PORCINE CARDIAC ARREST MODEL.

Objectives: Systemic ischemia-reperfusion triggered by cardiac arrest (CA) and resuscitation often causes postresuscitation multiple organ injuries. Mesenchymal stem cells (MSCs) have been proven to be a promising treatment for regional renal and intestinal ischemia reperfusion injuries. This study aimed to investigate the effects of MSCs on renal and intestinal injuries after cardiopulmonary resuscitation (CPR) in a porcine CA model. Methods: Twenty-two male pigs were randomly assigned to the sham (n = 6), CA/CPR (n = 8), and CA/CPR + MSC (n = 8) groups. Mesenchymal stem cells were differentiated from human embryonic stem cells and then intravenously administered at a dose of 2.5 × 10 6 /kg at 1.5 and 3 d before the CA/CPR procedure. The experimental model was established by 8 min of untreated CA, followed by 8 min of CPR. Renal and intestinal injuries were evaluated based on the serum levels of creatinine, serum urea nitrogen, intestinal fatty acid-binding protein, and diamine oxidase at 1, 2, 4, and 24 h after resuscitation. At the end of the experiment, pathological damage was determined by cell apoptosis and ferroptosis in the renal and intestinal tissues. Results: During CPR, five pigs in the CA/CPR group and seven pigs in the CA/CPR + MSC group were successfully resuscitated. After resuscitation, the serum levels of creatinine, serum urea nitrogen, intestinal fatty acid-binding protein, and diamine oxidase were significantly increased in the CA/CPR and CA/CPR + MSC groups compared with those in the sham group. However, MSC administration significantly decreased the levels of renal and intestinal injury biomarkers compared with those in the CA/CPR group. Cell apoptosis and ferroptosis, which were indicated by the levels of apoptotic cells, iron deposition, lipid peroxidation, antioxidants, and ferroptosis-related proteins, were observed in renal and intestinal tissues after resuscitation in the CA/CPR and CA/CPR + MSC groups. Nevertheless, both were significantly milder in the CA/CPR + MSC group than in the CA/CPR group. Conclusions: MSC administration was effective in alleviating postresuscitation renal and intestinal injuries possibly through inhibition of cell apoptosis and ferroptosis in a porcine CA model.

Hypothermic machine perfusion alleviates ischemia-reperfusion injury of intestinal transplantation in pigs.

Intestinal transplantation (IT) has become an important procedure for the treatment of irreversible intestinal failure. However, IT is extremely vulnerable to ischemia-reperfusion injury (IRI). Due to the limitations of static cold storage (SCS), hypothermic machine perfusion (HMP) is rapidly gaining popularity. In this study, the intestinal HMP system is established and HMP is compared with SCS. An intestinal HMP system was built. Ten miniature pigs were randomly divided into the HMP and SCS groups, and their intestines were perfused using the HMP device and SCS, respectively, followed by orthotopic auto-transplantation. Analysis was done on the grafts between the two groups. Operation success rates of the surgery were 100% in both groups. The 7-day survival rate was 100% in the HMP group, which was significantly higher than that of the SCS group (20%, P< 0.05). The pathological results showed that fewer injuries of grafts were in the HMP group. Endotoxin (ET), IL-1, IL-6, IFN-γ and TNF-α levels in the HMP group were significantly lower than in the SCS group (P<0.05), whereas IL-10 levels were significantly higher (P<0.05).The intestinal expression levels of ZO-1 and Occludin were higher in the HMP group compared to the SCS group, whereas Toll-like receptor 4 (TLR4), nuclear factor kappa B (NFκB), and caspase-3 were lower. In this study, we established a stable intestinal HMP system and demonstrated that HMP could significantly alleviate intestinal IRI and improve the outcome after IT.

When less is more: Experimental Bishop-Koop technique for reduction in the use of laboratory animals for intestinal pathophysiological studies.

The use of animals to gain knowledge and understanding of diseases needs to be reduced and refined. In the field of intestinal research, because of the complexity of the gut immune system, living models testing is mandatory. Based on the 3Rs (replacement, reduction and refinement) principles, we aimed to developed and apply the derived-intestinal surgical procedure described by Bishop and Koop (BK) in rats to refine experimental gastrointestinal procedures and reduce the number of animals used for research employing two models of intestinal inflammation: intestinal ischemia-reperfusion injury and chemical-induced colitis. Our results show the feasibility of the application of the BK technique in rodents, with good success after surgical procedure in both small and large intestine (100% survival, clinical recovery and weight regain). A considerable reduction in the use of the number of rats in both intestinal inflammation models (80% in case of intestinal ischemia-reperfusion damage and 66.6% in chemical-induced colitis in our experimental design) was achieved. Compared with conventional experimental models described by various research groups, we report excellent reproducibility of intestinal damage and functionality, survival rate and clinical status of the animals when BK is applied.

Single-cell analysis of cellular heterogeneity and interactions in the ischemia-reperfusion injured mouse intestine

Nine major cell populations among 46,716 cells were identified in mouse intestinal ischemia‒reperfusion (II/R) injury by single-cell RNA sequencing. For enterocyte cells, 11 subclusters were found, in which enterocyte cluster 1 (EC1), enterocyte cluster 3 (EC3), and enterocyte cluster 8 (EC8) were newly discovered cells in ischemia 45 min/reperfusion 720 min (I 45 min/R 720 min) group. EC1 and EC3 played roles in digestion and absorption, and EC8 played a role in cell junctions. For TA cells, after ischemia 45 min/reperfusion 90 min (I 45 min/R 90 min), many TA cells at the stage of proliferation were identified. For Paneth cells, Paneth cluster 3 was observed in the resting state of normal jejunum. After I 45 min/R 90 min, three new subsets were found, in which Paneth cluster 1 had good antigen presentation activity. The main functions of goblet cells were to synthesize and secrete mucus, and a novel subcluster (goblet cluster 5) with highly proliferative ability was discovered in I 45 min/R 90 min group. As a major part of immune system, the changes in T cells with important roles were clarified. Notably, enterocyte cells secreted Guca2b to interact with Gucy2c receptor on the membranes of stem cells, TA cells, Paneth cells, and goblet cells to elicit intercellular communication. One marker known as glutathione S-transferase mu 3 (GSTM3) affected intestinal mucosal barrier function by adjusting mitogen-activated protein kinases (MAPK) signaling during II/R injury. The data on the heterogeneity of intestinal cells, cellular communication and the mechanism of GSTM3 provide a cellular basis for treating II/R injury.

Daidzein alleviated the pathologies in intestinal tissue against ischemia-reperfusion.

The aim of this study was to investigate the effect of daidzein against intestinal ischemia-reperfusion injury in rats. Thirty male Wistar albino rats with a mean weight of 200-250 gr were used. Animals were categorized into sham, ischemia-reperfusion (IR), and IR+Daidzein group. 3-hour ischemia of intestine was created by occluding superior mesenteric artery and then left for 3-hour reperfusion. In IR+daidzein group, after ischemia, 50 mg/kg daidzein was orally administered to the animals. Blood samples were collected for biochemical assays. Intestine tissues were excised for histopathologic and immunohistochemical processing. Malondialdehyde (MDA) increased, and Catalase (CAT) and Glutathione (GSH) decreased after IR in intestine tissue. Daidzein treatment decreased MDA and increased CAT and GSH level in IR+Daidzein group. Histopathologically, sham group showed normal intestinal tissue histology. In IR group, epithelial and villi degeneration, edema, leukocyte infiltration, vascular dilatation and congestion was observed. After Daidzein treatment, these pathologies were improved. The caspase-6 expression was mainly negative in sham group. After IR, caspase-6 reaction was very high in IR group. Daidzein reduced caspase-6 expression in IR+Daidzein group. Ki67 immune staining was negative in the sham group. In IR group, Ki67 expression was increased in inflammatory cells, deep glandular cells and in some goblet cell nuclei. In IR+Daidzein group, Ki67 expression was decreased due to reduced inflammation. IR injury causes oxidative stress, apoptosis and inflammation. Daidzein treatment improved histopathology against intestinal IR.

Protective Effect of Oxygen and Isoflurane in Rodent Model of Intestinal Ischemia-Reperfusion Injury.

Animal research in intestinal ischemia-reperfusion injury (IRI) is mainly performed in rodent models. Previously, intraperitoneal (I.P.) injections with ketamine-xylazine mixtures were used. Nowadays, volatile anesthetics (isoflurane) are more common. However, the impact of the anesthetic method on intestinal IRI has not been investigated. We aim to analyze the different anesthetic methods and their influence on the extent of intestinal IRI in a rat model. Male Sprague-Dawley rats were used to investigate the effect of I.P. anesthesia on 60 min of intestinal ischemia and 60 min of reperfusion in comparison to hyperoxygenation (100% O2) and volatile isoflurane anesthesia. In comparison to I.P. anesthesia with room air (21% O2), supplying 100% O2 improved 7-day survival by cardiovascular stabilization, reducing lactic acidosis and preventing vascular leakage. However, this had no effect on the intestinal epithelial damage, permeability, and inflammatory response observed after intestinal IRI. In contrast to I.P. + 100% O2, isoflurane anesthesia reduced intestinal IRI by preventing ongoing low-flow reperfusion hypotension, limiting intestinal epithelial damage and permeability, and by having anti-inflammatory effects. When translating the aforementioned results of this study to clinical situations, such as intestinal ischemia or transplantation, the potential protective effects of hyperoxygenation and volatile anesthetics require further research.

Cystathionine gamma-lyase (Cth) induces efferocytosis in macrophages via ERK1/2 to modulate intestinal barrier repair

BackgroundThe inflammatory response induced by intestinal ischaemia‒reperfusion injury (I/R) is closely associated with infectious complications and mortality in critically ill patients, and the timely and effective clearance of apoptotic cells is an important part of reducing the inflammatory response. Studies have shown that the efferocytosis by phagocytes plays an important role. Recently, studies using small intestine organoid models showed that macrophage efferocytosis could promote the repair capacity of the intestinal epithelium. However, no studies have reported efferocytosis in the repair of I/R in animal models.ResultsWe used an in vivo efferocytosis assay and discovered that macrophage efferocytosis played an indispensable role in repairing and maintaining intestinal barrier function after I/R. In addition, the specific molecular mechanism that induced macrophage efferocytosis was Cth-ERK1/2 dependent. We found that Cth drove macrophage efferocytosis in vivo and in vitro. Overexpression/silencing Cth promoted/inhibited the ERK1/2 pathway, respectively, which in turn affected efferocytosis and mediated intestinal barrier recovery. In addition, we found that the levels of Cth and macrophage efferocytosis were positively correlated with the recovery of intestinal function in clinical patients.ConclusionCth can activate the ERK1/2 signalling pathway, induce macrophage efferocytosis, and thus promote intestinal barrier repair.ANik3mFzVX11c2tZJFb62zVideo

Современные представления о компонентном соотношении состава грудного молока у матерей, родивших преждевременно и в срок

To date, there have been sufficient data and information on the role of breast milk in nutrition, functional development of the newborn and the formation of immune responses. However, the influence of various factors on the component composition of breast milk remains poorly understood. This review presents data on the qualitative and quantitative changes in various organic and inorganic compounds in breast milk depending on the degree of prematurity of the newborn. In preterm birth and early onset of lactation, activation of the sialic acid production system may result in increased production of sialylated oligosaccharides involved in nervous system development. There are also contradictions in the information concerning the antioxidant content in breast milk. Some reports suggest that the milk of women who gave birth prematurely contains more antioxidants than that of women who gave birth at term. In contrast, other studies demonstrate a lower overall antioxidant function of breast milk in the early stages of lactation. Epidermal growth factor plays a significant role in providing protection against intestinal ischemia-reperfusion injury, hemorrhagic shock, and necrotizing enterocolitis. This article reviews domestic and foreign literature for the period 2012–2022 and aims to systematize the information on the composition of breast milk in women who gave birth at term and prematurely. Key words: breast milk, composition, preterm infants, full-term infants

Qingchang Mixture Prevents the Intestinal Ischemia-reperfusion Injury through TLR4/NF-kB Pathway.

This study aims to determine the protective effect and molecular responses of the traditional Chinese medicine Qingchang mixture on intestinal ischemia-reperfusion (IR) injury. The rat intestinal IR model was prepared. The intestinal ischemic injury was evaluated by HE staining, biochemical assay and western blot. In addition, a human hypoxia-reoxygenation (HR) in vitro model was prepared using intestinal epithelial cells (IEC-6). The viability and apoptosis of IEC-6 cells were measured by CCK8 and apoptosis detection. TAK242 or PDTC was used as a small molecule inhibitor of TLR4 or NF-κB, respectively. Compared with the IR group, the pretreatment of the Qingchang mixture reduced the morphological damage, oxidative stress, inflammatory response, and barrier function damage of the small intestine tissue. IR significantly increased the expression of TLR4 and NF-κB, while the pretreatment of the Qingchang mixture inhibited the expression of TLR4 and NF-κB. Furthermore, the pretreatment of Qingchang mixture, TAK242, or PDTC effectively improved the viability and hindered apoptosis of the HR-induced IEC-6 cells. Traditional Chinese medicine Qingchang mixture prevents intestinal IR injury through TLR4/NF-kB pathway.

Protective Mechanism of Ethyl Gallate against Intestinal Ischemia-Reperfusion Injury in Mice by in Vivo and in Vitro Studies Based on Transcriptomics.

Intestinal ischemia-reperfusion injury (IIRI) is a common clinical disease that can be life-threatening in severe cases. This study aimed to investigate the effects of ethyl gallate (EG) on IIRI and its underlying mechanisms. A mouse model was established to mimic human IIRI by clamping the superior mesenteric artery. Transcriptomics techniques were used in conjunction with experiments to explore the potential mechanisms of EG action. Intestinal histomorphological damage, including intestinal villi damage and mucosal hemorrhage, was significantly reversed by EG. EG also alleviated the oxidative stress, inflammation, and intestinal epithelial apoptosis caused by IIRI. 2592 up-regulated genes and 2754 down-regulated genes were identified after EG treatment, and these differential genes were enriched in signaling pathways, including fat digestion and absorption, and extracellular matrix (ECM) receptor interactions. In IIRI mouse intestinal tissue, expression of the differential protein matrix metalloproteinase 9 (MMP9), as well as its co-protein NF-κB-p65, was significantly increased, while EG inhibited the expression of MMP9 and NF-κB-p65. In Caco-2 cells in an established oxygen-glucose deprivation/reperfusion model (OGD/R), EG significantly reversed the decrease in intestinal barrier trans-epithelial electrical resistance (TEER). However, in the presence of MMP9 inhibitors, EG did not reverse the decreasing trend in TEER. This study illustrates the protective effect and mechanism of action of EG on IIRI and, combined with in vivo and in vitro experiments, it reveals that MMP9 may be the main target of EG action. This study provides new scientific information on the therapeutic effects of EG on IIRI.