Protective effects of polysaccharides from Atractylodes macrocephalae Koidz. against dextran sulfate sodium induced intestinal mucosal injury on mice.

In the present research, the water-soluble polysaccharides (AMP) from Atractylodes macrocephalae Koidz. were isolated and prepared. The protective effects of AMP on intestinal mucosal barrier injury induced by dextran sulfate sodium (DSS) in mice were investigated. It was found that AMP treatment significantly alleviated the body weight decreases and shorten colon length, and ameliorated colonic damage induced by DSS. Importantly, AMP prevented the over-expression of proinflammatory cytokines TNF-α, IL-1ß and IL-6, and decreased the infiltration of neutrophils in colon. Additionally, AMP could raise expressions of Mucin 2 and tight junction protein Claudin-1. AMP also modulated the intestinal microbiota by enhancing the overall richness and diversity, greatly reducing the proportion of harmful bacteria, for instance, Clostridiumsensu stricto1 and Escherichia Shigella, however, augmenting the ratio of potential beneficial bacteria such as Faecalibaculum and Bifidobacterium. This work offers some important insights on protective effects of polysaccharides AMP against intestinal barrier dysfunction and provides underlying mechanism of health-beneficial properties of these biological macromolecules.

Ginger and 6-gingerol prevent lipopolysaccharide-induced intestinal barrier damage and liver injury in mice.

BACKGROUND: Inflammation-related diseases present a significant public health problem. Ginger is a flavoring spice and medicinal herb with anti-inflammatory activity. This study investigated the preventive effects of ginger extract (GE) and its main bioactive component, 6-gingerol (6G), on lipopolysaccharide (LPS)-induced intestinal barrier dysfunction and liver injury in mice. RESULTS: GE and 6G were orally administered to mice for seven consecutive days before LPS administration. After 24 h, the mice were sacrificed. GE and 6G were found to significantly reverse LPS-induced inflammation in the mouse ileum by modifying the NF-κB pathway. They also alleviated apoptosis in the ileum by downregulating Bax and cytochrome c gene expression and by inhibiting the caspase-3 pathway. Through the aforementioned mechanisms, GE and 6G restored the intestinal barrier by increasing ZO-1 and claudin-1 protein expressions. Gut-derived LPS induced inflammation and apoptosis in the liver; these effects were markedly reversed through GE and 6G treatment. 6G was the most abundant component in GE, as evidenced through liquid chromatography-mass spectrometry, and accounted for >50% of total gingerols and shogaols in GE. CONCLUSION: The current results support the use of GE and 6G as dietary supplements to protect against gut-derived endotoxemia-associated inflammatory response and disorders. © 2021 Society of Chemical Industry.

Efficacy of Liangxue Guyuan decoction on radiation-induced intestinal injury in rats via the toll-like receptor 4/myeloid differentiation primary response 88/ nuclear factor-kappa B pathway.

OBJECTIVE: To evaluate the efficacy of Liangxue Guyuan decoction ( LGD) on radiation-induced intestinal injury in rats, and the possible underlying mechanism of action. METHODS: A total of 255 male Sprague-Dawley rats were used. 15 rats were assigned to the control group and the remaining 240 rats were exposed to a 60Co source at a dose of 11 Gy. Irradiated rats were randomly divided into model, dexamethasone (DXM), low-dose LGD (LGDl), and high-dose LGD (LGDh) groups and treated for 11 d. The survival rate, weight of body, intestinal pathology and the expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), and nuclear factor-kappa B (NF-κB) were recorded. RESULTS: Radiation reduced the survival rate and weight of rats, destroyed the intestinal structure, induced an inflammatory reaction, and increased both protein and mRNA expression of TLR4, MyD88, and NF-κB in ileum. However, LGDh increased the survival rate, inhibited weight loss, alleviated inflammation and improve the expression of TLR4 pathway. CONCLUSION: LGD increased the survival rate and inhibit weight loss of irradiated rats, and reduced inflammation and intestinal injury. The underlying mechanism may involve regulation of the TLR4/MyD88/NF-κB pathway.

Effects of Qing Hua Chang Yin on lipopolysaccharide­induced intestinal epithelial tight junction injury in Caco­2 cells.

Disruption of the intestinal mucosal barrier integrity is a pathogenic process in inflammatory bowel disease (IBD) development, and is therefore considered a drug discovery target for IBD. The well­known traditional Chinese formulation Qing Hua Chang Yin (QHCY) has been suggested as a potential therapeutic agent for the treatment of ulcerative colitis. However, the possible underlying molecular mechanisms regarding its therapeutic effect remain unclear. Consequently, the present study investigated the effects of QHCY on lipopolysaccharide (LPS)­induced loss of intestinal epithelial barrier integrity in vitro using the Caco­2 cell model of intestinal epithelium. QHCY reversed the LPS­induced decrease in transepithelial electrical resistance and significantly alleviated the increased fluorescently­labeled dextran 4 flux caused by LPS. Moreover, QHCY upregulated the mRNA and protein expression levels of occludin, zona occludens­1 and claudin­1 in LPS­exposed Caco­2 cells. In conclusion, QHCY was able to protect intestinal epithelial barrier integrity following an inflammatory insult; the protective effects of QHCY may be mediated by modulation of the expression of tight junction proteins.

Neuronal innervation of the intestinal crypt.

Mucosal damage is a key feature of inflammatory bowel diseases (IBD) and healing of the mucosa is an endpoint of IBD treatment that is often difficult to achieve. Autonomic neurons of the parasympathetic and sympathetic nervous system may influence intestinal epithelial cell growth and modulating epithelial innervation could for that reason serve as an interesting therapeutic option to improve mucosal healing. Understanding of the biological processes triggered by nonspecific and specific epithelial adrenergic and cholinergic receptor activation is of key importance. At present, with rising technological advances, bioelectronic neuromodulation as treatment modality has gained momentum. We discuss the current view on state-of-the-art innervation of the intestinal crypt and its impact on epithelial cell growth and differentiation. Furthermore, we outline bioelectronic technology and review its relevance to wound healing processes.

Glucagon-like peptide 2 attenuates intestinal mucosal barrier injury through the MLCK/pMLC signaling pathway in a piglet model.

Glucagon-like peptide-2 (GLP-2), an intestinotrophic hormone, has drawn considerable attention worldwide due to its potential to promote intestinal development. We investigated the effects and mechanisms of GLP-2 against lipopolysaccharide (LPS)-induced intestinal inflammation and injury both in vitro and in vivo. Forty healthy piglets weaned at the age of 28 days with similar body weight (BW) were assigned to four in vivo treatments with ten piglets each: (i) nonchallenged control; (ii) LPS-challenged control; (iii) LPS + low dose GLP-2; and (iv) LPS + high dose GLP-2. Piglets were subcutaneously injected with phosphate-buffered saline supplemented with GLP-2 at doses of 0, 0, 2, and 10 nmol/kg BW per day for seven consecutive days. The piglets were challenged with an intraperitoneal injection with 100 µg/kg LPS on day 14 to induce intestinal damage. After that, the gene and protein expression levels of representative tight junction proteins and myosin light-chain kinase (MLCK)/phosphorylated myosin light chain (pMLC), as well as proinflammatory cytokine levels were determined using quantitative reverse transcription polymerase chain reaction, western blot, and enzyme-linked immunosorbent assay methods. A high dose of GLP-2 pretreatment increased intestinal permeability by downregulating and redistributing tight junction proteins (p < .05), for example, zona occluden-1 (ZO-1) and occludin. GLP-2 decreased the transcription of proinflammatory cytokines genes including interleukin-1ß (IL-1ß), IL-6, IL-8, and tumor necrosis factor-α in small intestines (p < .05). GLP-2 prevented the LPS-induced increase in the expression of MLCK dose-dependently and the increase in pMLC levels in the duodenum, jejunum, and ileum. To assess further the protective effect of GLP-2 on LPS-induced intestinal barrier injury after weaning and its possible mechanism, an in vitro intestinal epithelial barrier model was established with IPEC-J2 monolayers and treated with 100 µg/ml LPS with or without 1 × 10-8 mol/L GLP-2 pretreatment. The in vitro analysis included control, LPS, and GLP-2 + LPS treatments. GLP-2 treatment alleviated the destructive effect of LPS on barrier permeability by restoring the expression and ultrastructure of ZO-1 and occludin (p < .05). In addition, GLP-2 reversed the LPS-induced MLCK hyperexpression and pMLC hyperphosphorylation (p < .05). Taken together, our findings revealed a mechanism by which GLP-2 alleviated LPS-challenged intestinal barrier injury and inflammation in weaned piglets and IPEC-J2 cells via the MLCK/pMLC signaling pathway.

Early intravenous administration of tranexamic acid ameliorates intestinal barrier injury induced by neutrophil extracellular traps in a rat model of trauma/hemorrhagic shock.

BACKGROUND: Early intravenous administration of tranexamic acid has been shown to protect the intestinal barrier after a model of trauma-hemorrhagic shock in the rat, but the potential mechanism remains unclear. Our previous studies have demonstrated that neutrophil extracellular traps contribute to the intestinal barrier dysfunction during sepsis and other critical conditions. Meanwhile, there are high levels of neutrophil infiltration in the intestine during trauma-hemorrhagic shock. Here, we hypothesized that neutrophil extracellular trap formation played a vital role during trauma-hemorrhagic shock-induced intestinal injury and that tranexamic acid, a serine protease inhibitor, may inhibit neutrophil extracellular trap formation and protect intestinal barrier function in trauma-hemorrhagic shock. METHODS: A model of trauma-hemorrhagic shock in male rats was established. The rats were divided into 6 groups: (1) sham group; (2) trauma-hemorrhagic shock group; (3) trauma-hemorrhagic shock + DNase I group; (4) trauma-hemorrhagic shock + tranexamic acid group; (5) trauma-hemorrhagic shock + tranexamic acid (different time) group; and (6) trauma-hemorrhagic shock + tranexamic acid (different doses) group. The DNase I solution was injected intravenously to disrupt neutrophil extracellular traps immediately after the trauma-hemorrhagic shock model was completed. After 24 hours, the small intestine and blood were collected for analysis. Human neutrophils were harvested and incubated with phorbol-12-myristate-13-acetate or tranexamic acid, generation of reactive oxygen species, and key proteins expression were detected. RESULTS: Trauma-hemorrhagic shock induced the formation of intestinal neutrophil extracellular traps and disrupted the intestinal tight junction proteins. Clearing of neutrophil extracellular traps by DNase I resulted in increased expression of tight junction proteins and alleviated the intestinal injury. Early intravenous tranexamic acid administration (1 hour after trauma-hemorrhagic shock) decreased neutrophil extracellular trap formation and prevented tight junction protein disruption compared to the non-tranexamic acid group; however, after delayed administration of tranexamic acid (6 hours), there were no changes in neutrophil extracellular trap formation and intestinal injuries compared to the non-tranexamic acid group. Furthermore, tranexamic acid inhibited neutrophil extracellular trap formation and protected the intestinal barrier in a dose-dependent manner and high-dose (20 mg/kg) treatment of tranexamic acid showed a better effect compared with the therapeutic dose (10 mg/kg). The results of thromboelastography demonstrated that the R and K values in the high-dose group decreased (R, 1.85 ± 0.14 vs 3.87 ± 0.16 minutes, P < .001; K, 0.95 ± 0.04 vs 1.48 ± 0.07 minutes, P < .001), accompanied by a decrease in LY30, indicating that treatment with a high dose of tranexamic acid may cause hypercoagulability and shutdown of fibrinolysis. In addition, less neutrophil extracellular trap formation was detected in neutrophils incubated with neutrophils via an reactive oxygen species-dependent pathway. CONCLUSION: We first demonstrated a novel role of neutrophil extracellular traps in the pathophysiology of intestinal barrier dysfunction during trauma-hemorrhagic shock. Notably, early but not delayed intravenous administration of tranexamic acid effectively inhibits neutrophil extracellular trap formation and protects intestinal barrier function. Therefore, these results suggested a potential theoretic intervention for the protection of the intestinal barrier during trauma-hemorrhagic shock. In such a process, tranexamic acid appears to regulate neutrophil extracellular trap formation via the classic reactive oxygen species/mitogen-activated protein kinase pathway.

Role of lactadherin in intestinal barrier integrity in experimental neonatal necrotizing enterocolitis.

Necrotizing enterocolitis (NEC) is one of the most widespread and devastating gastrointestinal diseases in neonates. Destruction of the intestinal barrier is the main underlying cause of NEC. The aim of this study was to determine the role of lactadherin in preventing NEC in a neonatal rat model and investigate the molecular mechanism of lactadherin-mediated protection of the intestinal barrier. Neonatal rats were divided into three groups: dam feeding (DF), NEC (NEC), and NEC supplemented with 10 µg/(g·day) recombinant human lactadherin (NEC+L). Intestinal permeability, tissue damage, and cell junction protein expression and localization were evaluated. We found that lactadherin reduced weight loss caused by NEC, reduced the incidence of NEC from 100% to 46.7%, and reduced the mean histological score for tissue damage to 1.40 compared with 2.53 in the NEC group. Intestinal permeability of lactadherin-treated rats was significantly reduced when compared with that of the NEC group. In addition, the expression levels of JAM-A, claudin 3, and E-calcium in the ileum of NEC group animals increased compared with those in the ileum of DF group animals, and these levels decreased in the NEC+L group. Lactadherin changed the localization of claudin 3, occludin, and E-cadherin in epithelial cells. The mechanism underlying lactadherin-mediated protection of the intestinal barrier might be restoring the correct expression levels and localization of tight junction and adherent junction proteins. These findings suggest a new candidate agent for the prevention of NEC in newborns.

Protective effect of magnolol on oxaliplatin-induced intestinal injury in mice.

Oxaliplatin (OXL) is the first line treatment therapy for gastrointestinal (GI) cancers and often combines with other chemotherapy. However, few reports have studied on its GI toxicity. Magnolol (MG), one of the mainly active constituents in Magnolia, has been reported to treat digestive diseases. Therefore, the purpose of this study is to evaluate the intestinal protective effect of MG in OXL treatment group. OXL administration mice showed body weight loss, diarrhea, and intestinal damage characterized by the shortening of villi and destruction of intestinal crypts, as well as the colon length change. MG significantly reduced body weight loss, alleviated diarrhea, reversed histopathological changes, and prevented colon length reduction. Oxidative stress and inflammation were activated after OXL, and these responses were repressed by MG through increasing the activities of superoxide dismutase, glutathione peroxidase, and glutathione, decreasing level of nuclear factor of kappa b and downregulating the following pro-inflammatory cytokines. Although the expression of tight junction protein occludin and numbers of proliferative crypt cells were reduced on ileum and colon after OXL, MG administration promoted these expressions. The fecal gut microbiota composition disturbed by OXL was significantly reversed by MG. Thus, MG could prevent the development and progression of mucositis induced by oxaliplatin through multipathway.

Astragalus membranaceus (Fisch.) Bunge repairs intestinal mucosal injury induced by LPS in mice.

BACKGROUND: Astragalus membranaceus (Fisch.) Bunge is one of the most widely used traditional Chinese herbal medicines. It is used as immune stimulant, tonic, antioxidant, hepatoprotectant, diuretic, antidiabetic, anticancer, and expectorant. The purpose of the study was to investigate the curative effects of the decoction obtained from Astragalus membranaceus root in intestinal mucosal injury induced by LPS in mice. An LPS-induced intestinal mucosal injury mice model was applied in the study. METHODS: The mice were post-treated with Astragalus membranaceus decoction (AMD) for 4 days after 3 days LPS induction. ELISA kit was used to detect the content of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-4,IL-6 and IL-8 in the serum of each group mice. The morphological changes in intestinal mucosa at the end of the experiments were observed. Both VH (villus height) and CD (crypt depth) were measured using H&E-stained sections. RESULTS: There were significant differences in IL-1ß, IL-4,IL-6, IL-8 and TNF-α levels in AMD-treated group on the 7th day compared to the controls group. The VH was lower in duodenum, jejunum and the ileum in LPS-treated mice compared to the control animals. Similarly, there was also decrease in V/C. Compared to the control mice, for AMD-treated mice, VH and CD had no significantly differences. CONCLUSIONS: Astragalus membranaceus reduced intestinal mucosal damage and promoted tissue repair by inhibiting the expression of inflammatory cytokine.

[Protective Effects of Acupuncture Intervention Against Damage of Intestinal Mucosal Barrier Induced by 5-Fluorouracil in Rats].

OBJECTIVE: To observe the effect of acupuncture intervention on the diarrhea, mucosal thickness of the small intestine, plasma endotoxin (ET) and D-lactic acid (D-LA) contents, and diamine oxidase (DAO) activity in 5-Fluorouracil (5-Fu) induced intestinal mucosal damage rats, in order to provide an experimental basis for acupuncture therapy in improving chemotherapy-induced intestinal mucosa injury. METHODS: Thirty female SD rats were randomly divided into control group, model group and acupuncture group (n = 10 in each group). The intestinal mucosal damage model was established by intraperitoneal injection of 5-Fu (50 mg/kg, for six consecutive days). Acupuncture stimulation was applied to bilateral "Tianshu" (ST 25) and "Zusanli" (ST 36) once a day for six consecutive days. The changes of body weight and diarrhea score (0-3 points, according to Kurita's methods) as well as mucosal thickness of the small intestine were determined. The plasma ET and D-LA contents, and DAO activity were measured by ELISA. RESULTS: On the sixth day, the body weight was significantly higher in the acupuncture group than in the model group (P<0.05). After intraperitoneal injection of 5-Fu, both the incidence rate and average score of diarrhea reached the peak on the sixth day in the model and acupuncture groups, and were significantly lower in the acupuncture group than in the model group (P<0.01). On the seventh day, the mucosal thickness of small intestine was significantly lower in the model group than in the control group (P<0.05), but had no remarkable changes after acupuncture intervention( P>0.05). The contents of plasma ET and D-LA and DAO activity level were significantly higher in the model group than in the control group, and markedly decreased in the acupuncture group than in the model group (P<0.01). CONCLUSION: Acupuncture intervention can lower the incidence rate and average score of diarrhea and down-regulate the increased plasma ET and D-LA contents and DAO activity levels in 5-Fu induced intestinal mucosal damage rats, suggesting a somewhat protective effect of acupuncture against chemotherapy induced damage of the intestinal mucosal barrier.

The injury of serotonin on intestinal epithelium cell renewal of weaned diarrhoea mice.

Diarrhoea is a common cause of death in children and weaned animals. Recent research has found that serotonin (5-HT) in the gastrointestinal tract plays an important role in regulating growth and the maintenance of mucosa, which protect against diarrhoea. To determine the influence of 5-HT on intestinal epithelium cell renewal under weaned stress diarrhoea, a weaned-stress diarrhoea mouse model was established with senna infusion (15 mL/Kg) via intragastric administration and stress restraint (SR). Mice with an increase in 5-HT were induced by intraperitoneal injection with citalopram hydrobromide (CH, 10 mg/Kg). The results demonstrated that compared with the control animals, diarrhoea appeared in weaned stress mice and the 5-HT content in the small intestine was significantly increased (P<0.05). Further, the caspase-3 cells and cells undergoing apoptosis in the small intestine were significantly increased, but the VH (villus height), V/C (villus height /crypt depth), and PCNA-positive rate significantly decreased. Compared with the control animals, CH increased the intestinal 5-HT content, caspase-3 cells and cells undergoing apoptosis but decreased the VH and V/C. Compared with both control and weaned stress animals, weaned stress animals that were pre-treated with CH showed higher 5-HT concentrations, positive caspase-3 cells and cells undergoing apoptosis but lower VH, V/C and PCNA-positive rate. In vitro, a low concentration of 5-HT inhibit, IEC-6 cell line apoptosis but a higher concentration of 5-HT promoted it. Therefore, weaned stress diarrhoea mice were accompanied by a 5-HT increase in the small intestine and vice versa, and the increase in 5-HT induced by CH caused diarrhoea. In brief, 5-HT and diarrhoea slowed the intestinal epithelium cell renewal and injured the abortion function and mucosal barrier by decreasing VH, V/C and proliferation and increasing epithelium cell apoptosis.

[Electrophysiological Characteristics of Sensitized Acupoints after Acute Intestinal Mucosal Injury in Rats].

OBJECTIVE: To observe the dynamic distribution of the extravasated Evans Blue (EB) dye points at the skin after acute colorectal mucosal injury (AIMI) so as to reveal characteristics of acupoint sensitization. METHODS: Forty adult male SD rats were randomly divided into control (n= 10), AIMI (n=20) and AIMI-recovery (n= 10) groups. According to the reaction state (EB-dye extravasation), each group was further divided into resting state (control), sensitized state (appearance of extravasated EB points), recovery state (disappearance of the extravasated EB points), non-sensitization (NS, no extravasated EB points) state and NS recovery state. The AIMI model was induced by perfusion of 2. 5% mustard oil into the colorectum via a thin tube. Evans blue dye was injected into the caudal vein 4 h after AIMI modeling. The distribution of plasma extravasated EB dye points at the skin of the lower limbs was observed. The C-fiber discharge of the separated ipsilateral sciatic nerve was induced by electrical stimulation of the EB-extravasated acupoints and non-acupoint at the threshold and double-fold threshold using an electric stimulator and recorded using a bicelectric amplifier-computer system. RESULTS: In AIMI rats, the extravasated EB-dye points were found to overlap the "Xiqian" and "Zusanli" (ST 36)-"Shangjuxu"(ST 37) regions. Moreover, the thresholds of C-fiber discharges induced by electrical stimulation of "Xiqian" and "Zusanli" (ST 36)-"Shangluxu"(ST 37) regions were significantly lower than those of the regions without extravasated EB dye acupoint and non-acupoint(P<0. 01, P<0. 05). The numbers of C-fiber discharges evoked by 2-fold threshold electro-stimulation at the "Xiqian" and "Zusanli" (ST 36)-"Shangjuxu" (ST 37) regions were obviously more than those of stimulation of non-acupoint which were experiencing sensitized state(P<0. 01, P<0. 05). CONCLUSION: In rats with acute colorectal mucosal injury, electrical stimulation of the acupoints where the extravasated EB-dye points appear may produce an obvious increase of C-fiber discharges under lower electro-stimulation threshold, suggesting a larger action of the sensitized acupoint.

[Pretreatment with Xuebijing injection alleviates systemic inflammatory response induced by severe heat-stroke via ameliorating intestinal injury in rats].

OBJECTIVE: To observe the effect of Xuebijing injection pretreatment on systemic inflammatory response induced by severe heat-stroke, and to investigate the mechanism of alleviation of intestinal injury in rats. METHODS: Thirty-six healthy adult male Wistar rats with grade SPF were randomly assigned into three groups with randomized number method, namely sham group, severe heat-stroke model group, and Xuebijing pretreatment group ( XBJ group ), with 12 rats in each group. The animals were placed in a pre-warm chamber [ temperature ( 40±2 ) centigrade, humidity ( 65±5 )% ] in order to induce typical heat-stroke. The duration of heat-stress was 60 minutes, while the animals in sham group were exposed to ambient temperature of 25 centigrade. Arterial blood samples were collected at the beginning and the end of heat-stress, the concentrations of tumor necrosis factor-α( TNF-α), interleukins ( IL-1ß, IL-6 ), and lipopolysaccharide ( LPS ) in peripheral blood were determined by enzyme linked immunosorbent assay ( ELISA ). The intestinal tissues were harvested after heat-stress, and the pathological changes in intestine tissues were observed after hematoxylin-eosin ( HE ) staining and under optical microscope. The pathological injury scores were calculated. Immunohistochemistry was performed to determine inducible nitric oxide synthase ( iNOS ) expression in intestinal tissue. Apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling ( TUNEL ) staining. Western Blot was used to measure the tight junction protein occludin expression. RESULTS: The concentrations of TNF-α, IL-1ß, IL-6 and LPS in blood of the rats after heat-stress in model group were significantly higher than those of sham group [ TNF-α ( µg/L ): 443.00±110.10 vs. 98.36±44.61, IL-1ß ( µg/L ): 436.37±163.64 vs.64.24±16.15, IL-6 ( µg/L ): 342.70±92.42 vs. 54.40±13.22, LPS ( µg/L ): 0.68±0.22 vs. 0.09±0.02, all P < 0.01 ], but the levels of these parameters in XBJ group were significantly lower than those of model group [ TNF-α ( µg/L ): 340.45±68.57 vs. 443.00±110.10, IL-1ß ( µg/L ): 191.33±82.78 vs. 436.37±163.64, IL-6 ( µg/L ): 192.21±37.89 vs. 342.70±92.42, LPS ( µg/L ): 0.43±0.17 vs. 0.68±0.22, all P < 0.01 ]. Infiltration of inflammatory cells, necrosis and hemorrhage in intestinal mucosa were found in the intestine of heat-stroke animals in model group. The pathological lesions in XBJ group were milder than those of model group, with a decreased pathological injury score compared with model group ( 2.10±1.15 vs. 3.20±0.67, P < 0.01 ). The expression of iNOS and apoptosis of cells in intestinal tissue in model group were increased compared with that of sham group, but they were significantly less marked in XBJ group compared with model group [ iNOS ( adjusted A value ): 0.32±0.15 vs. 0.74±0.17, apoptotic index: 0.23±0.08 vs. 0.56±0.07, both P < 0.01 ]. The order of expression for occludin protein from high to low was sham group, XBJ group and model group ( A value was 0.96±0.25, 0.62±0.20, 0.33±0.11, respectively ). Furthermore, there was significant difference in the expression of occludin protein between model group and both XBJ group and sham group ( both P < 0.01 ). CONCLUSIONS: Xuebijing injection alleviates inflammation and endotoxemia produced by severe heat-stroke in rats. The mechanism may be related to amelioration of oxidative injury, apoptosis, and dysfunction of tight junction protein occludin expression.

Activation of transcription factor AP-1 in response to thermal injury in rat small intestine and IEC-6 cells.

BACKGROUND: Our previous studies indicated that heat stress can cause significant damage to the intestinal epithelium and induce differential expression of many genes in rat small intestine. The transcription factors AP-1 and NF-κB, which act as important mediators by binding to specific DNA sequences within gene promoters, regulate the transcription of genes associated with immune regulation, stress response and cell fate. METHODS: To determine whether AP-1 and NF-κB are involved in hyperthermia-induced injury in rat small intestine and IEC-6 cells, we investigated their activity, and the expression of related proteins, by electrophoretic mobility shift assays and western blotting, respectively. RESULTS: Heat stress resulted in severe damage to the epithelium of the small intestine. The cell morphology and viability were obviously altered when IEC-6 cell was exposed to hyperthermia. AP-1 was activated in the small intestine of heat-stressed rats, as was phosphorylation of the JNK signaling pathway. In IEC-6 cell line, AP-1 activation in groups exposed to 42 °C for 1 h, 2 h and 4 h was significantly increased. In contrast, NF-κB was not activated in both in vivo and in vitro models. CONCLUSION: These results reveal that AP-1 is likely to play an important role in regulating gene transcription in rat small intestine and IEC-6 cells during exposure to heat stress.

Ação trófica de aditivos fitogênicos, glutamina e ácido glutâmico sobre a Bursa de Fabrícius e intestino delgado de frangos de corte / Trophic action of phytogenic additives, glutamine and glutamic acid on Bursa Fabricii and small intestine of broilers

The aim of this study was to evaluate the effect of phytogenic additives and glutamine plus glutamic acid, associated or not, on histomorphometry of bursa of Fabricius and small intestine, oocyst count and lesion scores, and carbon turnover of duodenal mucosa of broiler chickens infected with Eimeria acervulina. A total of 450 male broiler chickens was distributed into a completely randomized design with six treatments and three replications. Treatments consisted of control diet (CD); CD + coccidiosis vaccine; CD + antibiotic performance enhancers and anticoccidial (APE/AC); CD + glutamine and glutamic acid (Gln/Glu); CD + phytogenic additives (PA); CD + Gln/Glu + PA. Birds on treatment CD + vaccine were vaccinated via drinking water at three days of age against coccidiosis. At 16 days of age all birds of all treatments were inoculated orally and individually with 500,000 oocysts of Eimeria acervulina. There was no treatment effect on lesion score in the intestinal epithelium of birds. The smaller number of excreted oocysts was observed in groups of birds fed diets containing APE/AC and PA. Were observed better results of villus height and crypt depth for duodenum and ileum of birds of treatments containing Gln/Glu at 7 days of age, and Gln/Glu and PA at 21 days of age. Higher percentage of cortical area from bursa follicles was observed in birds fed diets supplemented with Gln/Glu and PA at 7, 14 and 21 days of age. Increased turnover of intestinal mucosa was observed in treatments containing Gln/Glu, indicating acceleration in development and regeneration of damaged tissue. Glutamine plus glutamic acid and phytogenic additives can provide improvements to structure, and thus to intestinal function, as well as to better immune response against the infectious challenges. Phytogenic additives can be used for coccidiosis control of broiler chickens where the use of antibiotic performance enhancers and anticoccidials is prohibited...

O objetivo deste trabalho foi avaliar o efeito dos aditivos fitogênicos e da glutamina mais ácido glutâmico, associados ou não, sobre a histomorfometria da Bursa de Fabricius e intestino delgado, sobre contagem de oocistos e escores de lesão e sobre o turnover do carbono da mucosa intestinal de frangos de corte experimentalmente infectadas com Eimeria acervulina. Para isso foram utilizados 450 pintos de corte machos distribuídos em delineamento inteiramente casualisado, com seis tratamentos e três repetições. Os tratamentos consistiram de dieta controle (DC); DC + Vacina de coccidiose; DC + antibióticos melhoradores de desempenho e anticoccidiano (AMD/AC); DC + glutamina e ácido glutâmico (Gln/Glu); DC + sditivos fitogênicos (AFs); DC + Gln/Glu + AFs. As aves do tratamento DC + Vacina foram vacinadas via água de bebida, aos três dias de idade, contra coccidiose. Aos 16 dias de idade todas as aves de todos os tratamentos foram inoculadas oralmente e individualmente com 500.000 oocistos de Eimeria acervulina. Não houve efeito dos tratamentos para escore de lesão no epitélio intestinal das aves. O menor número de oocistos excretados foi observado nos grupos de aves alimentadas com dieta contendo AMD/AC e AFs. Foram observados melhores resultados para altura das vilosidades e profundidade das criptas do duodeno e ílio das aves dos tratamentos contendo Gln/Glu, aos 7 dias de idade e Gln/Glu e AFs aos 21 dias de idade. Maior porcentagem de área cortical dos folículos bursais foi observada em aves alimentadas com dieta suplementada com Gln/Glu e AFs aos 7, 14 e 21 dias de idade. Maior turnover da mucosa intestinal foi observada em aves dos tratamentos contendo Gln/Glu, indicando aceleração do desenvolvimento e regeneração do tecido lesado. Glutamina mais ácido glutâmico e aditivos fitogênicos podem oferecer melhorias à estrutura e, consequentemente, à função do intestino, bem como melhores condições para resposta imune frente à desafios infecciosos...

Beneficial effects of Camellia Oil (Camellia oleifera Abel.) on ketoprofen-induced gastrointestinal mucosal damage through upregulation of HO-1 and VEGF.

Nonsteroidal anti-inflammatory drugs, such as ketoprofen, are generally used to treat pain and inflammation and as pyretic agents in clinical medicine. However, the usage of these drugs may lead to oxidative injury to the gastrointestinal mucosa. Camellia oil ( Camellia oleifera Abel.) is commonly used in Taiwan and China as cooking oil. Traditional remedies containing this oil exert beneficial health effects on the bowel, stomach, liver, and lungs. However, the effects of camellia oil on ketoprofen-induced oxidative gastrointestinal mucosal lesions remain unknown. The objective of this study was to evaluate the effect of camellia oil on ketoprofen-induced acute gastrointestinal ulcers. The results showed that treatment of Int-407 cells with camellia oil (50-75 µg/mL) not only increased the levels of heme oxygenase-1 (HO-1), glutathione peroxidase (GPx), and superoxide dismutase (SOD) mRNA expression but also increased vascular endothelial growth factor (VEGF) and prostaglandin E2 (PGE2) protein secretion, which served as a mucosal barrier against gastrointestinal oxidative injury. Moreover, Sprague-Dawley (SD) rats treated with camellia oil (2 mL/kg/day) prior to the administration of ketoprofen (50 mg/kg/day) successfully inhibited COX-2 protein expression, inhibited the production of interleukin-6 (IL-6) and nitrite oxide (NO), reversed the impairment of the antioxidant system, and decreased oxidative damage in the gastrointestinal mucosa. More importantly, pretreatment of SD rats with camellia oil strongly inhibited gastrointestinal mucosal injury induced by ketoprofen, which was proved by the histopathological staining of gastrointestinal tissues. Our data suggest that camellia oil exerts potent antiulcer effects against oxidative damage in the stomach and intestine induced by ketoprofen.

Diamine oxidase as a marker of intestinal mucosal injury and the effect of soluble dietary fiber on gastrointestinal tract toxicity after intravenous 5-fluorouracil treatment in rats.

The level of plasma diamine oxidase (DAO) activity is associated with the maturation and integrity of small intestinal mucosa. This study in rats investigated whether a decreased level of plasma DAO could reflect the severity of mucosal injury due to intravenous 5-fluorouracil (5-FU) treatment. The beneficial effect of soluble dietary fiber (SDF) on preventing diarrhea after 5-FU treatment was also examined. To induce diarrhea, 5-FU (50 mg/kg/day for four days) was administered via the tail vein with or without SDF supplementation. After 5-FU treatment, the majority of rats developed moderate to severe diarrhea, and levels of plasma DAO activity significantly decreased compared to those of control group (P < 0.05). Scanning electron microscopy revealed disarrangement of the small intestinal villi. Contrarily, the rats supplemented with SDF had diarrhea less frequently (50.0 vs. 91.7 %, P = 0.025) on day five, and DAO activity levels were significantly higher than in those rats administered 5-FU alone (8.25 ± 5.34 vs. 5.50 ± 4.32, P = 0.023). In conclusion, plasma DAO activity decreases in response to severe intestinal mucosal injury after 5-FU treatment, and SDF supplementation might be a practical and useful treatment for reducing the intestinal toxicity of 5-FU.

Protective effect of genistein on radiation-induced intestinal injury in tumor bearing mice.

BACKGROUND: Radiation therapy is the most widely used treatment for cancer, but it causes the side effect of mucositis due to intestinal damage. We examined the protective effect of genistein in tumor-bearing mice after abdominal irradiation by evaluation of apoptosis and intestinal morphological changes. METHODS: Mouse colon cancer CT26 cells were subcutaneously injected at the flank of BALB/c mice to generate tumors. The tumor-bearing mice were treated with abdominal radiation at 5 and 10 Gy, and with genistein at 200 mg/kg body weight per day for 1 d before radiation. The changes in intestinal histology were evaluated 12 h and 3.5 d after irradiation. To assess the effect of the combination treatment on the cancer growth, the tumor volume was determined at sacrifice before tumor overgrowth occurred. RESULTS: Genistein significantly decreased the number of apoptotic nuclei compared with that in the irradiation group 12 h after 5 Gy irradiation. Evaluation of histological changes showed that genistein ameliorated intestinal morphological changes such as decreased crypt survival, villus shortening, and increased length of the basal lamina 3.5 d after 10 Gy irradiation. Moreover, the genistein-treated group exhibited more Ki-67-positive proliferating cells in the jejunum than the irradiated control group, and crypt depths were greater in the genistein-treated group than in the irradiated control group. The mean weight of the CT26 tumors was reduced in the group treated with genistein and radiation compared with the control group. CONCLUSION: Genistein had a protective effect on intestinal damage induced by irradiation and delayed tumor growth. These results suggest that genistein is a useful candidate for preventing radiotherapy-induced intestinal damage in cancer patients.

[Protective effect of baicalin against LPS-induced intestinal injury].

OBJECTIVE: To investigate the protective effect of baicalin on the intestinal mucosal injury caused by endotoxin-lipopolysaccharide (LPS) and the anti-oxidative injury in colonic and ileal mucosa of rats with septicopyemia. METHOD: Fifty healthy male BALB/c mice were randomly divided into 5 groups: the normal control group, the model group, and baicalin high-dose, medium-dose and low-dose groups. They were orally administered with double distilled water, 100 mg x kg(-1) of baicalin, 50 mg x kg(-1) of baicalin, and 25 mg x kg(-1) of baicalin respectively for three days, once a day. 1 h after the oral administration on 3 d, they were intraperitoneally injected with normal saline or LPS (17 mg x kg(-1)). At 20 h after the injection of LPS, all of the mice were sacrificed, and their colonic and ileal tissues were collected. The mental status, life state and death rate of mice in each group were observed, and the lengths of colonic were measured. Chiu's scoring method was used to assess the intestinal mucosal injury. Histopathological changes of intestinal tissues were tested by HE staining. The ultraviolet spectrophotometry was used to detect total antioxidant capacity (T-AOC), superoxide dismutase (T-SOD), and glutathione peroxidase (GSH-PX) of intestinal homogenate. The immunohistochemical method was used to analyze the expression of PCNA in intestinal tissues of each group. RESULT: The death of mice was observed after the intraperitoneal injection of LPS. The death rates of baicalin groups were remarkably lower than the death rate of the model group. The colons in the medium-dose baicalin group were much longer than that in the model group (P < 0.05), with a much lower intestinal mucosa injury degree than the model group. Colonic and ileal injuries in the high-dose baicalin group significantly (P < 0.05). Colonic and ileal injuries in the medium-dose baicalin group and the low-dose baicalin group significantly reduced compare with the model group (P < 0.000 1). The medium-dose baicalin group showed no significant increase in homogenate's T-AOC, T-SOD and GSH-PX compare with the model group (P < 0.05). There was no significant difference between baicalin groups and the model group in PCNA. CONCLUSION: Baicalin can protect intestinal epithelial cells suffering from injury from oxygen radicals, and relieve the intestinal injury caused by LPS by improving the intestinal mucosa structure and functions.