Surgical choice for the treatment of partial intestinal ischemic necrosis caused by acute type a aortic dissection combined with malperfusion of superior mesenteric artery.

Acute type A aortic dissection is a severe cardiovascular disease characterized by rapid onset and high mortality. Traditionally, urgent open aortic repair is performed after admission to prevent aortic rupture and death. However, when combined with malperfusion syndrome, the low perfusion of the superior mesenteric artery can further lead to intestinal necrosis, significantly impacting the surgery's prognosis and potentially resulting in adverse consequences, bringing. This presents great significant challenges in treatment. Based on recent domestic and international research literature, this paper reviews the mechanism, current treatment approaches, and selection of surgical methods for poor organ perfusion caused by acute type A aortic dissection. The literature review findings suggest that central aortic repair can be employed for the treatment of acute type A aortic dissection with inadequate perfusion of the superior mesenteric artery. The superior mesenteric artery can be windowed and (/or) stented, followed by delayed aortic repair. Priority should be given to revascularization of the superior mesenteric artery, followed by central aortic repair. During central aortic repair, direct blood perfusion should be performed on the distal true lumen of the superior mesenteric artery, leading to resulting in favorable therapeutic outcomes. The research results indicate that even after surgical aortic repair, intestinal ischemic necrosis may still occur. In such cases, prompt laparotomy and necessary necrotic bowel resection are crucial for saving the patient's life.

The Evaluation and Management of Intestinal Ischemia.

AbstractIntestinal ischemia can result from various pathologic conditions. The presentations of ischemia can range from acute to subacute and mild to severe. Diagnosis of this condition may pose challenges, particularly in the early, potentially salvageable, stages of disease. This review offers an evidence-based approach to understanding the diagnosis and management of inadequate intestinal perfusion.

Abdominal Wall Closure in Intestinal and Multivisceral Transplantation: A State-Of-The-Art Review of Vascularized Abdominal Wall and Nonvascularized Rectus Fascia Transplantation.

Failure to close the abdomen after intestinal or multivisceral transplantation (Tx) remains a frequently occurring problem. Two attractive reconstruction methods, especially in large abdominal wall defects, are full-thickness abdominal wall vascularized composite allograft (AW-VCA) and nonvascularized rectus fascia (NVRF) Tx. This review compares surgical technique, immunology, integration, clinical experience, and indications of both techniques. In AW-VCA Tx, vascular anastomosis is required and the graft undergoes hypotrophy post-Tx. Furthermore, it has immunologic benefits and good clinical outcome. NVRF Tx is an easy technique without the need for vascular anastomosis. Moreover, a rapid integration and neovascularization occurs with excellent clinical outcome.

Laser speckle flowgraphy has comparable accuracy to indocyanine green fluorescence angiography in assessing bowel blood perfusion.

PURPOSE: To investigate the accuracy of laser speckle flowgraphy (LSFG), a noninvasive method for the quantitative evaluation of blood flow using mean blur rate (MBR) as a blood flow parameter in the assessment of bowel blood perfusion compared to indocyanine green fluorescence angiography (ICG-FA). METHODS: We enrolled 46 patients who underwent left-sided colorectal surgery. LSFG and ICG-FA were applied to assess blood bowel perfusion, with MBR and luminance as parameters, respectively. In both measurement methods, the position where the parameter suddenly decreased was defined as the blood flow boundary line. Subsequently, the blood flow boundaries created after processing the blood vessels flowing into the intestinal tract were determined using LSFG and ICG-FA, and concordance between the two was examined. Blood flow boundaries were visually identified using color tone changes on a color map created based on MBR in LSFG and using differences in luminance in ICG-FA. The distances between the transection line and blood flow boundaries determined using each method were compared. RESULTS: The location of blood flow boundaries matched in 65% (30/46) of cases. Although locations differed in the remaining 35% (16/46), all were located on the anal side near the transection line, and the difference was not clinically significant. The average distances between the transection line and blood flow boundary were 2.76 (SD = 3.25) and 3.71 (SD = 4.26) mm, respectively. There was no statistically significant difference between the two groups (p = 0.38). CONCLUSION: LSFG was shown to have comparable accuracy to ICG-FA, and may be useful for evaluating bowel perfusion.

PRMT6-FOXO3A ATTENUATES APOPTOSIS BY UPREGULATING PARKIN EXPRESSION IN INTESTINAL ISCHEMIA-REPERFUSION INJURY.

ABSTRACT: Intestinal ischemia-reperfusion injury (IIRI) is a serious disease with high morbidity and mortality. This study aims to investigate the potential regulatory mechanisms involving protein arginine methyltransferase 6 (PRMT6), Forkhead box O3a (FoxO3a), and Parkin in IIRI and elucidate their roles in mediating cell apoptosis. The IIRI animal model was established and confirmed using hematoxylin and eosin staining. Oxygen-glucose deprivation and reperfusion (OGD/R) cell model was established to mimic ischemic injury in vitro . Transient transfection was used to overexpress or knock down genes. Cell death or apoptosis was assessed by propidium iodide staining, terminal deoxynucleotidyl transferase dUTP nick end labeling assay, and flow cytometry. The expression of proteins was detected by western blot. The histopathology observed by hematoxylin and eosin staining suggested that the IIRI animal model was successfully established. Our findings revealed that IIRI resulted in increased Bax and decreased Bcl-2 levels. In vitro experiments showed that overexpression of Parkin decreased OGD/R injury and suppressed elevation of Bax/Bcl-2. PRMT6 regulated the methylation level of FoxO3a. Moreover, FoxO3a directly binds to Parkin, and FoxO3a overexpression reduced OGD/R-induced cell death and regulation of Parkin. Overexpression of PRMT6 can attenuate the downregulation of Parkin and elevation of Bax/Bcl-2 caused by OGD/R. Knockdown of PRMT6 promoted apoptosis in intestinal epithelial cells of OGD/R group, while PRMT6 overexpression exhibited the opposite effect. Notably, the levels of PRMT6, FoxO3a, and Parkin were decreased in IIRI mouse intestinal tissue. Knocking out PRMT6 causes a significant decrease in the lifespan of mice. Altogether, our results demonstrated that PRMT6 upregulated the expression of Parkin by regulating FoxO3a methylation level, attenuating the apoptosis induced by IIRI.

EFFECTS OF HYPERBARIC OXYGEN THERAPY ON INTESTINAL ISCHEMIA-REPERFUSION AND ITS MECHANISM.

ABSTRACT: Ischemia can cause reversible or irreversible cell or tissue damage, and reperfusion after ischemia not only has no therapeutic effect but also aggravates cell damage. Notably, gut tissue is highly susceptible to ischemia-reperfusion (IR) injury under many adverse health conditions. Intestinal IR (IIR) is an important pathophysiological process in critical clinical diseases. Therefore, it is necessary to identify better therapeutic methods for relieving intestinal ischemia and hypoxia. Hyperbaric oxygenation refers to the intermittent inhalation of 100% oxygen in an environment greater than 1 atm pressure, which can better increase the oxygen level in the tissue and change the inflammatory pathway. Currently, it can have a positive effect on hypoxia and ischemic diseases. Related studies have suggested that hyperbaric oxygen can significantly reduce ischemia-hypoxic injury to the brain, spinal cord, kidney, and myocardium. This article reviews the pathogenesis of IR and the current treatment measures, and further points out that hyperbaric oxygen has a better effect in IR. We found that not only improved hypoxia but also regulated IR induced injury in a certain way. From the perspective of clinical application, these changes and the application of hyperbaric oxygen therapy have important implications for treatment, especially IIR.

Apigenin-7-glucoside-loaded nanoparticle alleviates intestinal ischemia-reperfusion by ATF3/SLC7A11-mediated ferroptosis.

Intestinal ischemia reperfusion injury (II/R injury) is a common and intractable pathophysiological process in critical patients, for which exploring new treatments and mechanisms is of great importance to improve treatment outcomes. Apigenin-7-O-Glucoside (AGL) is a sugar derivative of apigenin natural product with various pharmacological activities to protect against intestinal diseases. In this study, we synthesized two amphiphilic molecules, namely DTPA-N10-10 and mPEG-TK-DA, which can scavenge free radicals and reactive oxygen species (ROS). They were successfully encapsulated AGL through self-assembly, resulting in the formation of multi-site ROS scavenging nanoparticles called PDN@AGL. In vitro and in vivo experiments demonstrated that PDN@AGL could protect intestinal tissues by reducing lipid peroxidation, lowering ROS levels and inhibiting ferroptosis during II/R injury. Furthermore, our study revealed, for the first time, that the regulation of the ATF3/SLC7A11 pathway by PDN@AGL may play a crucial role in mitigating II/R injury. In conclusion, our study confirmed the beneficial effects of PDN@AGL in combating II/R injury through the ATF3/SLC7A11-mediated regulation of ferroptosis and oxidative stress. These findings lay the groundwork for the potential application of PDN@AGL in the treatment of II/R injury.

INT-767-A Dual Farnesoid-X Receptor (FXR) and Takeda G Protein-Coupled Receptor-5 (TGR5) Agonist Improves Survival in Rats and Attenuates Intestinal Ischemia Reperfusion Injury.

Intestinal ischemia is a potentially catastrophic emergency, with a high rate of morbidity and mortality. Currently, no specific pharmacological treatments are available. Previous work demonstrated that pre-treatment with obeticholic acid (OCA) protected against ischemia reperfusion injury (IRI). Recently, a more potent and water-soluble version has been synthesized: Intercept 767 (INT-767). The aim of this study was to investigate if intravenous treatment with INT-767 can improve outcomes after IRI. In a validated rat model of IRI (60 min ischemia + 60 min reperfusion), three groups were investigated (n = 6/group): (i) sham: surgery without ischemia; (ii) IRI + vehicle; and (iii) IRI + INT-767. The vehicle (0.9% NaCl) or INT-767 (10 mg/kg) were administered intravenously 15 min after start of ischemia. Endpoints were 7-day survival, serum injury markers (L-lactate and I-FABP), histology (Park-Chiu and villus length), permeability (transepithelial electrical resistance and endotoxin translocation), and cytokine expression. Untreated, IRI was uniformly lethal by provoking severe inflammation and structural damage, leading to translocation and sepsis. INT-767 treatment significantly improved survival by reducing inflammation and preserving intestinal structural integrity. This study demonstrates that treatment with INT-767 15 min after onset of intestinal ischemia significantly decreases IRI and improves survival. The ability to administer INT-767 intravenously greatly enhances its clinical potential.

Gallic acid treatment protects intestinal tissue against ischaemia-reperfusion.

BACKGROUND: This study aimed to investigate the protective effects of gallic acid (GA) in the rat intestine against ischaemia-reperfusion (IR) injury. MATERIALS AND METHODS: Thirty male Wistar albino rats with a mean weight of 200-250 g were used. Animals were categorized into the sham, IR, and IR+GA groups. Ischaemia of the intestine was induced for 3 h by occluding the superior mesenteric artery (SMA) and then left for 3 h of reperfusion. In the IR+GA group, after ischaemia induction, 50 mg/kg GA was orally administered to the animals. Blood samples were collected for biochemical assays. Intestinal tissues were excised for histopathologic and immunohistochemical processing. RESULTS: Malondialdehyde (MDA) levels were increased, and catalase (CAT) and glutathione (GSH) levels were decreased in the IR group compared to the sham group. After GA treatment, MDA levels decreased and CAT and GSH levels increased in the GA-treated group compared to the IR group. In the sham group, normal intestinal histology was observed. In the IR group, the villi structures were completely degenerated. In the IR+GA group, histology was improved after GA treatment. In the sham group, the caspase-3 reaction was generally negative in the epithelium and glands. In the IR group, the caspase-3 reaction increased in apoptotic bodies and inflammatory cells. The caspase-3 reaction was negative in goblet cells and the epithelium. A moderate caspase-3 reaction was observed in the IR+GA group. The beclin-1 reaction was negative in epithelial cells and goblet cells in villi in the sham group. In the IR group, the beclin-1 reaction was positive in the degenerated villi. An intense beclin-1 reaction was also observed in some inflammatory cells. After GA treatment, the beclin-1 reaction was positive in a few cells. In general, moderate beclin-1 positivity was observed. CONCLUSIONS: Gallic acid, with its antioxidative effect, inhibited the apoptotic pathway (caspase-3) through beclin-1 regulation.

Cysteamine Attenuate Intestinal Reperfusion Injury Induced by Occlusion of Mesenteric Artery by Enhancing Intracellular Thiol Activities.

BACKGROUND: Ischemia/reperfusion has been reported to further damage the intestine reperfusion injury (IRI) and cause multiple distal organ dysfunction through oxidative stress, inflammation, and apoptosis. Cysteamine is known to inhibit oxidative stress, inflammatory cytokines and apoptosis. This experiment was designed to evaluate the role of cysteamine against IRI in rats METHODS: Thirty-two Wistar rat strains were assigned to four groups: sham, Intestinal-reperfusion injury (IRI), 50 mg/kg and 100 mg/kg cysteamine treatment IRI. A 5 cm segment of terminal ileum was twisted 360° clockwise along the mesentery for 45 minutes to induce ischemia before detorsion. Tissues were preserved for biochemical evaluation and histology 4 hours after detorsion. Activities of GPx, GSH, protein and non-protein thiol, H2O2, MDA were evaluated. Serum concentration of nitrite, MPO, ALT, AST TNF-alpha and IL-6 were measured. Caspase 3 and bax were evaluated by immunohistochemistry. Statistical significance was set as p<0.05 RESULTS: Significant (p<0.05) increase in H2O2, MDA and nitrite but reduction in GPx, GSH, protein thiol and non-protein thiol in the IRI rats was reversed by 50 and 100 mg/kg cysteamine. Serum MPO, TNF-α, IL6, AST and ALT was significantly elevated in IRI while the rats treated with cysteamine showed a significant decrease (p<0.05) in the activities of these inflammatory and hepatic injury markers. CONCLUSION: Cysteamine mitigate IRI by enhancing intracellular antioxidant defense system, inhibiting inflammatory mediators and intestinal tissue expression of pro-apoptotic protein.

Prognostic factors in patients with acute mesenteric ischemia-novel tools for determining patient outcomes.

BACKGROUND: Acute mesenteric ischemia (AMI) is a devastating disease with poor prognosis. Due to the multitude of underlying factors, prediction of outcomes remains poor. We aimed to identify factors governing diagnosis and survival in AMI and develop novel prognostic tools. METHODS: This monocentric retrospective study analyzed patients with suspected AMI undergoing imaging between January 2014 and December 2019. Subgroup analyses were performed for patients with confirmed AMI undergoing surgery. Nomograms were calculated based on multivariable logistic regression models. RESULTS: Five hundred and thirty-nine patients underwent imaging for clinically suspected AMI, with 216 examinations showing radiological indication of AMI. Intestinal necrosis (IN) was confirmed in 125 undergoing surgery, 58 of which survived and 67 died (median 9 days after diagnosis, IQR 22). Increasing age, ASA score, pneumatosis intestinalis, and dilated bowel loops were significantly associated with presence of IN upon radiological suspicion. In contrast, decreased pH, elevated creatinine, radiological atherosclerosis, vascular occlusion (versus non-occlusive AMI), and colonic affection (compared to small bowel ischemia only) were associated with impaired survival in patients undergoing surgery. Based on the identified factors, we developed two nomograms to aid in prediction of IN upon radiological suspicion (C-Index = 0.726) and survival in patients undergoing surgery for IN (C-Index = 0.791). CONCLUSION: As AMI remains a condition with high mortality, we identified factors predicting occurrence of IN with suspected AMI and survival when undergoing surgery for IN. We provide two new tools, which combine these parameters and might prove helpful in treatment of patients with AMI.

EFFECTS OF 2-METHYL-2-THIAZOLINE ON CIRCULATORY DYNAMICS AND INTESTINAL VASCULAR SYSTEM IN RABBITS WITH ENDOTOXIC SHOCK.

ABSTRACT: We hypothesized that circulatory and jejunal mucosal blood flow would improve after 2-methyl-2thiazoline (2MT) administration in endotoxic shock. This study aimed to evaluate changes in systemic circulation and in superior mesenteric venous (SMV) blood flow and jejunal mucosal tissue blood flow of the intestinal vascular system over time after administration of 2MT in rabbits with endotoxic shock. We created four groups (n = 6 each): control group, LPS (1 mg/kg) group, 2MT (80 mg/kg) group, and LPS-2MT group. As indicators of circulation, we measured MAP, heart rate, cardiac index, lactic acid level, SMV blood flow, and jejunal mucosal tissue blood flow every 30 min from 0 to 240 min. The drop in MAP observed in the LPS group was suppressed by 2MT administration. Superior mesenteric venous blood flow dropped temporarily with LPS administration but then rose thereafter. After administration of 2MT to the LPS group, SMV blood flow began to rise earlier than that in the LPS group and did not decline below that of the control group thereafter. In the LPS group, jejunal mucosal tissue blood flow transiently decreased and then increased but at a lower level than that in the control group. However, in the LPS-2MT group, although a transient decrease in jejunal mucosal tissue blood flow was observed, its flow then improved to the level of the control group. An interaction between 2MT and LPS was observed for jejunal mucosal tissue blood flow from 90 to 180 min and at 240 min (P < 0.05). We showed that 2MT maintained MAP and improved SMV blood flow and jejunal mucosal tissue blood flow. In a rabbit model of endotoxic shock, 2MT had a positive effect on MAP and jejunal mucosal tissue blood flow.

S1PR2/RhoA/ROCK1 pathway promotes inflammatory bowel disease by inducing intestinal vascular endothelial barrier damage and M1 macrophage polarization.

Vascular and immune dysfunctions are thought to be related to the pathogenesis of inflammatory bowel disease (IBD), but behind this, the exact mechanism of mucosal vascular endothelial barrier dysfunction and macrophage phenotypic transition is not fully understood. Here, we explored the mechanistic role of sphingosine 1-phosphate receptor 2 (S1PR2) and its downstream G protein RhoA/Rho kinase 1 (ROCK1) signaling pathway in the intestinal endothelial barrier damage and M1 macrophage polarization in IBD. We found that the expression of S1PR2 in intestinal mucosal vascular endothelial cells and macrophages of IBD patients and DSS-induced colitis mice as well as vascular endothelial cells and macrophages treated with LPS in vitro was significantly increased. Knocking down or pharmacologically inhibiting S1PR2 significantly downregulated the expression of RhoA and ROCK1 in vascular endothelial cells and macrophages. Furthermore, inhibition of S1PR2 and ROCK1 reversed the impaired vascular barrier function and M1 macrophage polarization in vivo and in vitro, while reducing ER stress in vascular endothelial cells and glycolysis in macrophages. In addition, inhibition of ER stress or glycolysis reversed LPS-induced impairment of vascular endothelial cell barrier function and M1 macrophage polarization. Collectively, our results indicate that the S1PR2/RhoA/ROCK1 signaling pathway may participate in the pathogenesis of IBD by regulating vascular endothelial barrier function and M1 macrophage polarization.

Embarazo con miomatosis uterina complicado con isquemia intestinal: reporte de un caso / Pregnancy with uterine myomatosis complicated by intestinal ischemia: case report

Resumen Los miomas uterinos, también conocidos como fibromas o leiomiomas, son los tumores uterinos benignos más prevalentes. Afectan a las mujeres principalmente durante sus años reproductivos y se diagnostican hasta en un 70% de las mujeres blancas y en más del 80% de las mujeres de ascendencia africana durante su vida, con una prevalencia durante el embarazo del 2% al 10%. Pueden ser asintomáticos hasta en un 70% de las pacientes, y se estima que pueden ocurrir complicaciones en aproximadamente una de cada 10 mujeres embarazadas. Se han asociado a complicaciones y resultados adversos del embarazo, según su tamaño y ubicación en el útero, y pueden manifestarse de diferentes formas. Presentamos el caso de una mujer de 30 años, con embarazo en el tercer trimestre, quien consultó por dolor abdominal, con ecografías obstétricas durante su control prenatal que reportaban miomatosis uterina, quien presentó isquemia intestinal por un vólvulo de intestino delgado versus compresión extrínseca.

Abstract Uterine fibroids, also known as fibroids or leiomyomas, are the most prevalent benign uterine tumors, affecting women mainly during their reproductive years and are diagnosed in up to 70% of white women and more than 80% of women of African descent during their lifetime, with a prevalence during pregnancy of 2% to 10%; they may be asymptomatic in up to 70% of patients, and it is estimated that complications may occur in approximately one in 10 pregnant women. They have been associated with complications and adverse pregnancy outcomes, depending on their size and location in the uterus, they can manifest in different ways. We present the case of a 30-year-old woman, pregnant in the third trimester, who consulted for abdominal pain, with obstetric ultrasound scans during her prenatal check-up reporting uterine myomatosis, who presented intestinal ischemia due to small bowel volvulus versus extrinsic compression.

[CT angiography and endovascular treatment in acute mesenteric ischemia]. / KT-angiografiya i endovaskulyarnye vmeshatel'stva pri ostroi mezenterial'noi ishemii ­ pervye rezul'taty.

OBJECTIVE: To optimize the treatment strategy for acute mesenteric ischemia (AMI). MATERIAL AND METHODS: The study included 43 patients aged 76.4±10.3 years. CT angiography and endovascular repair of mesenteric vessels underlie the new treatment approach. RESULTS: CT angiography according to the established criteria was performed in 31 patients with suspected AMI throughout 1 year. Sensitivity was 90.0%, specificity - 100%, accuracy - 95%. Endovascular interventions were applied in 13 patients (successful in 8 cases and unsuccessful in 5 patients). Mortality rate was 37.5%. Fifteen patients with clinical signs of peritonitis or after previous unsuccessful interventional revascularization underwent open surgery. Mortality rate was 86.7%. CONCLUSION: CT angiography is valuable to diagnose AMI at the stage of reversible changes in bowel wall in some cases. Endovascular revascularization as the first-line treatment has certain prospects.

A cell atlas of microbe-responsive processes in the zebrafish intestine.

Gut microbial products direct growth, differentiation, and development in animal hosts. However, we lack system-wide understanding of cell-specific responses to the microbiome. We profiled cell transcriptomes from the intestine, and associated tissue, of zebrafish larvae raised in the presence or absence of a microbiome. We uncovered extensive cellular heterogeneity in the conventional zebrafish intestinal epithelium, including previously undescribed cell types with known mammalian homologs. By comparing conventional to germ-free profiles, we mapped microbial impacts on transcriptional activity in each cell population. We revealed intricate degrees of cellular specificity in host responses to the microbiome that included regulatory effects on patterning and on metabolic and immune activity. For example, we showed that the absence of microbes hindered pro-angiogenic signals in the developing vasculature, causing impaired intestinal vascularization. Our work provides a high-resolution atlas of intestinal cellular composition in the developing fish gut and details the effects of the microbiome on each cell type.

Histone deacetylase inhibitors (HDACi) increase expression of KCa2.3 (SK3) in primary microvascular endothelial cells.

The small conductance calcium-activated potassium channel (KCa2.3) has long been recognized for its role in mediating vasorelaxation through the endothelium-derived hyperpolarization (EDH) response. Histone deacetylases (HDACs) have been implicated as potential modulators of blood pressure and histone deacetylase inhibitors (HDACi) are being explored as therapeutics for hypertension. Herein, we show that HDACi increase KCa2.3 expression when heterologously expressed in HEK cells and endogenously expressed in primary cultures of human umbilical vein endothelial cells (HUVECs) and human intestinal microvascular endothelial cells (HIMECs). When primary endothelial cells were exposed to HDACi, KCa2.3 transcripts, subunits, and functional current are increased. Quantitative RT-PCR (qPCR) demonstrated increased KCa2.3 mRNA following HDACi, confirming transcriptional regulation of KCa2.3 by HDACs. By using pharmacological agents selective for different classes of HDACs, we discriminated between cytoplasmic and epigenetic modulation of KCa2.3. Biochemical analysis revealed an association between the cytoplasmic HDAC6 and KCa2.3 in immunoprecipitation studies. Specifically inhibiting HDAC6 increases expression of KCa2.3. In addition to increasing the expression of KCa2.3, we show that nonspecific inhibition of HDACs causes an increase in the expression of the molecular chaperone Hsp70 in endothelial cells. When Hsp70 is inhibited in the presence of HDACi, the magnitude of the increase in KCa2.3 expression is diminished. Finally, we show a slower rate of endocytosis of KCa2.3 as a result of exposure of primary endothelial cells to HDACi. These data provide the first demonstrated approach to increase KCa2.3 channel number in endothelial cells and may partially account for the mechanism by which HDACi induce vasorelaxation.

Experimental study to assess the impact of vasopressors administered during maintenance of the brain-dead donation in the quality of the intestinal graft.

BACKGROUND: The hemodynamic maintenance of brain-dead donors will influence the quality of the organs procured for transplantation, including the intestine. Although norepinephrine (NE) and dopamine (DA) are commonly used to sustain mean arterial pressure in humans, there are no standardized protocols for their use during maintenance of brain-dead donors. Our aim was to compare the effects of each drug, in the intestinal graft quality using a rat brain-dead donation model. METHODS: Wistar rats (N = 17) underwent brain death (BD) for 2 hours with NE (NE group) or with DA (DA group) administration; the control group was mechanically ventilated for 2 hours without BD. Jejunum biopsies were obtained at the end of the maintenance period. Histological damage was evaluated using Park-Chiu scale. Villi/crypt ratio, mucosal thickness, Goblet cell count, and villi density were evaluated using ImageJ software (US National Institutes of Health, Bethesda, MD). Barrier damage was assessed by bacterial translocation culture counting on liver samples. The inflammatory status of the intestine was evaluated by CD3+ counting by immunohistochemistry and gene expression analysis of interleukin (IL)-6, IL-22, and CXCL10. RESULTS: Norepinephrine-treated donors had higher focal ischemic injury in the intestinal mucosa without a substantial modification of morphometrical parameters compared with DA-treated donors. CD3+ mucosal infiltration was greater in intestines procured from brain-dead donors, being highest in NE (p ˂ 0.001). Local inflammatory mediators were affected in BD: DA and NE groups showed a trend to lower expression of IL-22, whereas CXCL10 expression was higher in NE versus control group. Brain death promoted intestinal bacterial translocation, but the use of NE resulted in the highest bacterial counting in the liver (p ˂ 0.01). CONCLUSION: Our results favor the use of DA instead of NE as main vasoactive drug to manage BD-associated hemodynamic instability. Dopamine may contribute to improve the quality of the intestinal graft, by better preserving barrier function and lowering immune cell infiltration.

BACKGROUND: The hemodynamic maintenance of brain-dead donors will influence the quality of the organs procured for transplantation, including the intestine. Although norepinephrine (NE) and dopamine (DA) are commonly used to sustain mean arterial pressure in humans, there are no standardized protocols for their use during maintenance of brain-dead donors. Our aim was to compare the effects of each drug, in the intestinal graft quality using a rat brain-dead donation model. METHODS: Wistar rats (N = 17) underwent brain death (BD) for 2 hours with NE (NE group) or with DA (DA group) administration; the control group was mechanically ventilated for 2 hours without BD. Jejunum biopsies were obtained at the end of the maintenance period. Histological damage was evaluated using Park-Chiu scale. Villi/crypt ratio, mucosal thickness, Goblet cell count, and villi density were evaluated using ImageJ software (US National Institutes of Health, Bethesda, MD). Barrier damage was assessed by bacterial translocation culture counting on liver samples. The inflammatory status of the intestine was evaluated by CD3 + counting by immunohistochemistry and gene expression analysis of interleukin (IL)-6, IL-22, and CXCL10. RESULTS: Norepinephrine-treated donors had higher focal ischemic injury in the intestinal mucosa without a substantial modification of morphometrical parameters compared with DA-treated donors. CD3 + mucosal infiltration was greater in intestines procured from brain-dead donors, being highest in NE ( p ˂ 0.001). Local inflammatory mediators were affected in BD: DA and NE groups showed a trend to lower expression of IL-22, whereas CXCL10 expression was higher in NE versus control group. Brain death promoted intestinal bacterial translocation, but the use of NE resulted in the highest bacterial counting in the liver ( p ˂ 0.01). CONCLUSION: Our results favor the use of DA instead of NE as main vasoactive drug to manage BD-associated hemodynamic instability. Dopamine may contribute to improve the quality of the intestinal graft, by better preserving barrier function and lowering immune cell infiltration.

Correlation between endoscopy and intestinal ultrasound for the evaluation of postoperative recurrence of Crohn's disease. / Correlación entre la endoscopia y la ecografía intestinal para la evaluación de la recurrencia posquirúrgica de la enfermedad de Crohn.

OBJECTIVE: Intestinal ultrasound is considered to be a valid alternative for the evaluation of post-operative recurrence (POR) of Crohn's disease. The aim of this study is to assess the correlation between ultrasound and endoscopic findings. METHODS: Patients with Crohn's disease were retrospectively recruited who had undergone ileocecal resection, and for whom a colonoscopy and intestinal ultrasound had been performed for the detection of POR. Recurrence was assessed using the Rutgeerts score (RS). The ultrasound findings analysed were bowel wall thickness (BWT), parietal hyperaemia using power Doppler, loss of layer pattern and mesenteric fat hypertrophy. RESULTS: A total of 31 patients were included, of which 15 (48.4%) had no POR (RS<2b) and 16 (51.6%) had POR (RS≥2b). A statistically significant association was identified between BWT and the presence of endoscopic recurrence (a mean of 2.75mm vs. 5.68mm, P>0.001). There was also a statistically significant difference in hyperaemia between the 2groups (P=0.03). For wall thickness, an area under the ROC curve (AUC) of 92.9% was obtained, and with a cut-off point of 3.4mm, a sensitivity of 100% and specificity of 86.6%. When comparing with the most frequent biomarkers (fecal calprotectin and serum CRP), a higher AUC was obtained for wall thickness (72.3% and 72.3% vs. 92.9%). CONCLUSIONS: In our experience, ultrasound has high diagnostic efficacy in the detection of POR and can be considered a valid non-invasive alternative to endoscopy.

miR-146a-5p/TXNIP axis attenuates intestinal ischemia-reperfusion injury by inhibiting autophagy via the PRKAA/mTOR signaling pathway.

Autophagy is being increasingly recognized as an important regulator of intestinal ischemia-reperfusion(I/R)injury, but its exact role is still debated. Emerging evidence suggests that miR-146a-5p is involved in the initiation and development of I/R injury, but its role in intestinal I/R injury remains unclear. The present study generated an intestinal I/R mouse model and an oxygen glucose deprivation/reoxygenation (OGD/R) Caco-2 cell model and found that autophagy was increased and contributed to the intestinal injury and cell death induced by I/R and OGD/R. In addition, in both I/R and OGD/R models, the miR-146a-5p expression level was decreased and accompanied by an increase in TXNIP expression. By transfecting cells with an miR-146a-5p inhibitor or mimic, we observed that miR-146a-5p inhibits autophagy during OGD/R by targeting TXNIP; this was confirmed by the dual luciferase reporter gene assay. Additionally, through overexpression and knockdown cell lines, we established that TXNIP regulates autophagy during intestinal I/R via the PRKAA/mTOR pathway. The interaction between TXNIP and p-PRKAA was verified by immunofluorescence co-localization and immunoprecipitation assays. Moreover, we confirmed that TXNIP is indispensable for miR-146a-5p-mediated cell protection. Finally, we observed that miR-146a-5p overexpression inhibits autophagy and attenuates intestinal I/R injury via the PRKAA/mTOR pathway by targeting TXNIP in vivo. In conclusion, this study highlights the role of miR-146a-5p in regulating autophagy by targeting TXNIP, suggesting that miR-146a-5p may be a novel drug target for intestinal I/R therapy.