WTAP-induced N6-methyladenosine of PD-L1 blocked T-cell-mediated antitumor activity under hypoxia in colorectal cancer.

N6-Methyladenosine (m6A) is a important process regulating gene expression post-transcriptionally. Programmed death ligand 1 (PD-L1) is a major immune inhibitive checkpoint that facilitates immune evasion and is expressed in tumor cells. In this research we discovered that Wilms' tumor 1-associated protein (WTAP) degradation caused by ubiquitin-mediated cleavage in cancer cells (colorectal cancer, CRC) under hypoxia was inhibited by Pumilio homolog 1 (PUM1) directly bound to WTAP. WTAP enhanced PD-L1 expression in a way that was m6A-dependent. m6A "reader," Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) identified methylated PD-L1 transcripts and subsequently fixed its mRNA. Additionally, we found that T-cell proliferation and its cancer cell-killing effects were prevented by overexpression of WTAP in vitro and in vivo. Overexpression prevented T cells from proliferating and killing CRC by maintaining the expression of PD-L1. Further evidence supporting the WTAP-PD-L1 regulatory axis was found in human CRC and organoid tissues. Tumors with high WTAP levels appeared more responsive to anti-PD1 immunotherapy, when analyzing samples from patients undergoing treatment. Overall, our findings demonstrated a novel PD-L1 regulatory mechanism by WTAP-induced mRNA epigenetic regulation and the possible application of targeting WTAP as immunotherapy for tumor hypoxia.

The importance of preoperative T3 stage substaging by 3D endorectal ultrasonography for the prognosis of middle and low rectal cancer.

OBJECTIVE: The study aimed to validate the role of 3D-endorectal ultrasonography in prognosis and recurrence for patients with T3-stage rectal cancer by evaluating the preoperative extramural depth of tumor invasion. METHODS: In this study, we investigated the medical records of rectal cancer patients who were admitted to Changhai Hospital's Colorectal Surgery Division. The sample group was categorized into three subgroups (T3a, T3b, and T3c) based on the extent of tumor progression (<5 mm, 5-10 mm, and >10 mm) to assess the endorectal ultrasonography diagnostic performance. The 5-year disease-free survival and overall survival were assessed using the Kaplan-Meier method and a log rank test. Cox regression analysis verified the tumor invasion depth's significance as a prognostic predictor, and it was also utilized to evaluate other independent risk variables for recurrence after surgery. RESULTS: The study included 72 individuals with low and middle rectal cancer from January 2014 to November 2019. Twenty-two individuals had stage T3a, 22 had stage T3b, and 28 had stage T3c based on preoperative endorectal ultrasonography. Endorectal ultrasonography had 88.0%, 86.8%, and 76.2% overall accuracy for stratifying subgroups, respectively. According to the Kaplan-Meier curve, 5-year OS was 100%, 83.5%, and 92.9% for T3a, T3b, and T3c (p = 0.172), and 5-year disease-free survival was 100%, 80.8%, and 72.9% for T3a, T3b, and T3c, respectively (p = 0.014). A distinct risk factor for 5-year disease-free survival was the degree of tumor infiltration (p = 0.039). CONCLUSION: Preoperative T3 stage subdivision allows for categorization of prognosis and survival. Endorectal ultrasonography reports should make explicit declarations of T3a, T3b, and T3c scales.

CD142 plays an important role in the mobility of colorectal cancer cells.

CD142 promotes cell mobility, which contributes to carcinogenesis. However, the role of CD142 on colorectal cancer (CRC) mobility is unclear. This study showed that CD142 expression increased in CRC tissues, especially in those with invasion or metastasis. The positive sorting or overexpression of CD142 promoted the invasion and migration of CRC cells. Overall, CD142 may be responsible for CRC mobility.

Mapping of DNA Hypermethylation and Hypomethylation induced by Folate Deficiency in Sporadic Colorectal Cancer and Clinical Implication Analysis of Hypermethylation Pattern in CBS Promoter.

BACKGROUND: Aberrant DNA methylation patterns play a major role in tumorigenesis and the effects of nutrients, especially folate in the diet, on methylation changes is of great importance in colorectal cancer (CRC). Folate deficiency would disrupt methylation patterns; however, its exact effects on DNA methylation patterns in CRC are unclear. This study was performed to gain insight into the methylation changes induced by folate deficiency and the putative role of methylation pattern diversities of related genes in the clinical outcome of CRC. METHODS: The NimbleGen MeDIP chip (Methylated DNA Immunoprecipitation chip) assay was used in high-resolution mapping of DNA methylation patterns in the normal human colon mucosal epithelial cell line, NCM460 cultured with or without folate. Aberrant CpG island methylation patterns in the promoter of genes were identified by chip assay and then were confirmed in paired colorectal tissues and corresponding non-malignant tissues obtained from patients by bisulfate sequencing PCR (BSP). Of the total, the expression of cystathionine-beta-synthase (CBS) involved in methyl metabolism and its important substrate, homocysteine, were all detected by realtime RT-PCR and immunostaining. We also analyzed the data of its hypermethylation level statistically correlated with pathological parameters and the clinical outcome in malignant tissues. RESULTS: The chip assay showed that there are 17 genes with hyper or hypomethylation in CpG islands of promoter on chromosome 21, and 8 of them seemed to be associated with tumorigenesis. Among the total, a hypermethylation patterns existed in the promoter of CBS in CRC (p < 0.001), and the hypermethylation is related with the down-regulation of CBS and the accumulation of homocysteine in vitro and vivo (p < 0.001). Univariate analysis showed CBS hypermethylation level is correlated with age (p < 0.001), pT stage (p = 0.008), pN stage (p = 0.038), liver metastasis (p = 0.017), pTNM stage (p = 0.032), Dukes' stage (p = 0.022), recurrence (p = 0.041), five-year survival (p = 0.034), recurrence-free probability (p = 0.011), and overall survival (p = 0.018). Multivariate analysis showed that CBS hypermethylation level significantly correlated with recurrence rate (p = 0.039) and overall survival (p = 0.012) independent of pT stage, pN stage, and liver metastasis. CONCLUSIONS: Folate deficiency could induce aberrant DNA methylation patterns and gene expressions in CRC. CBS plays a critical role in tumorigenesis and could serve as a prognostic marker for tumor progression.

Thirty-day rat toxicity study reveals reversible liver toxicity of mifepristone (RU486) and metapristone.

OBJECTIVE: Mifepristone (RU486) is an oral first-line contraceptive used by hundreds of millions of women, and recently it was tested for anticancer activity in both genders worldwide. We are developing metapristone (the N-monodemethyl RU486) as a potential metastasis chemopreventive. The present acute and 30-d subacute toxicity study aimed at examining and compared in parallel the potential toxicity of the two drugs. METHODS: The single-dose acute toxicity and 30-d subacute toxicity studies were conducted in mice and rats, respectively, by gavaging metapristone or mifepristone at various doses. Blood samples and organs were collected for blood chemistry, hematology and histology analyses. RESULTS: Oral mifepristone (3000 mg/kg) caused 30% and 40% death in female and male mice, respectively, within 15 h post-dosing. In comparison, the same dose of metapristone produced 30% acute death in males only. Thirty-day oral administration of the two drugs to rats (12.5, 50 and 200 mg/kg/day) caused reversible hepatotoxicity that only occurred at 200 mg/kg/day group, evidenced by the elevated liver enzyme activity and liver organ weight. CONCLUSION: The present study, for the first time, reveals reversible hepatotoxicity in rats caused by the 30-d consecutive administration at the high dose, and warns the potential hepatotoxicity caused by long-term administrations of high doses of mifepristone or metapristone in clinical trials but not by the acute single abortion doses.

"Fast track" rehabilitation after gastric cancer resection: experience with 80 consecutive cases.

BACKGROUND: To evaluate the safety, efficacy and outcomes of fast-track rehabilitation applied to gastric cancer proximal, distal and total gastrectomy. METHODS: Eighty consecutive patients undergoing gastric cancer resection performed by a single surgeon, received perioperative multimodal rehabilitation. Demographic and operative data, gastrointestinal function, postoperative hospital stays, surgical and general complications and mortality were assessed prospectively. RESULTS: Of the 80 patients (mean age 56.3 years), 10 (12.5%) received proximal subtotal gastrectomy (Billroth I), 38 (47.5%) received distal (Billroth II), and 32 (40%) received total gastrectomy (Roux-en-Y). Mean operative time was 104.9 minutes and intraoperative blood loss was 281.9 ml. Time to first flatus was 2.8 ± 0.5 postoperative days. Patients were discharged at a mean of 5.3 ± 2.2 postoperative days; 30-day readmission rate was 3.8%. In-hospital mortality was 0%; general and surgical complications were both 5%. CONCLUSIONS: Fast-track multimodal rehabilitation is feasible and safe in patients undergoing gastric cancer resection and may reduce time to first flatus and postoperative hospital stays.

[Correlation of methylation of CpG island in cystathionine beta synthase promoter and clinicopathological features in colorectal cancer].

OBJECTIVE: To explore the association between methylation of cystathionine-beta-synthase (CBS) promoter and clinicopathological features in colorectal cancer. METHODS: Bisulfate sequencing PCR, real-time RT-PCR, and immunohistochemistry were used to investigate the methylation of CpG island in CBS promoter of 95 sporadic colorectal cancers. Software SPSS PASW Statistics was used to analyze the data of the hypermethylation levels in the malignant tissues and the correlation with pathological parameters and clinical outcome. RESULTS: Methylation levels in tumor tissue of patients [(64.9 ± 14.3)%]with colorectal cancer were significantly higher than that in normal tissues[(27.5 ± 13.1)%, P < 0.001]. The CBS mRNA levels in the hypomethylation group (7.22 ± 1.91) were significantly higher than that in the hypermethylation group (2.78 ± 1.12, P < 0.01). Univariate analysis showed that age, pT stage, pN stage, liver metastases, pTNM stage, and CBS hypermethylation level significantly correlated with the survival and recurrence rates of colorectal cancer patients (All P < 0.05). Multivariate analysis showed that CBS hypermethylation level and liver metastasis were independent factors significantly correlated with the recurrence rate and overall survival of the patients (All P < 0.05). CONCLUSIONS: Our study indicates that methylation of CpG island in CBS promoter is correlated with the occurrence and progression of colorectal cancer and plays a role in its tumorigenesis. It might serve as a useful marker for early diagnosis, targeted therapy and prediction of prognosis in colorectal cancer.

Fourth-line targeted drugs for the long-term treatment of patients with secondary gastrointestinal stromal tumors with multisite mutations: a case report.

BACKGROUND: The surgical treatment of small intestinal stromal tumors is mainly based on the common experience of gastrointestinal stromal tumors (GISTs). The biological characteristics of tumors and secondary gene mutations during disease progression cause many difficulties in clinical treatment. Advanced GISTs usually have no chance to surgery especially after multiple lines of drug therapy and multiple surgeries. This case report provides a good example of rensformational surgery for advanced GIST. CASE DESCRIPTION: In this report, we describe the case of a patient that is male 57 years old with a small intestinal stromal tumor (stage IV) treated in our center (The First Medical Centre, Chinese PLA General Hospital, Beijing, China) who underwent more than 20 years of first- to fourth-line tyrosine kinase inhibitor (TKI) drug treatment and three rounds of surgical treatment. In June 2020, the patient developed extensive metastases in the abdominal cavity, pelvic cavity, and liver, and could not be treated surgically. The patient was enrolled in the "two-arm clinical trial of bridge therapy with ripretinib and sunitinib in China", started four cycles of ripretinib drug therapy and tumor evaluation, and eventually achieved tumor remission. The patient received surgical treatment following conversion therapy and postoperative tumor recurrence. After continued targeted therapy with TKIs, disease progression was controlled, and the patient's survival was prolonged. CONCLUSIONS: Type II TKIs such as ripretinib and avapritinib have enhanced the typically expected therapeutic effects of many advanced GISTs. For the late-line treatment of advanced GIST, new TKI drugs can be tried for conversion therapy while monitoring the whole process, grasp the timing of surgery to provide more effective treatment.

Up-regulation of PUM1 by miR-218-5p promotes colorectal tumor-initiating cell properties and tumorigenesis by regulating the PI3K/AKT axis.

Background: Colorectal cancer (CRC) is the third most common cancer and the fourth most common cause of cancer-related death worldwide. Advanced stage CRC, during the recent past, had a dismal prognosis and only a few available treatments. Pumilio homologous protein 1 (PUM1) is reportedly aberrant in human malignancies, including CRC. However, the role of PUM1 in the regulation of tumor-initiating cells (T-ICs) remains unknown. Methods: The levels of messenger RNAs (mRNAs) were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunoblot analyses. Statistical analyses were performed to determine the associations between the levels of PUM1 and tumor features and patient outcomes. Whether PUM1 is a downstream target of miR-218-5p was verified by bioinformatics target gene prediction and qRT-PCR. Results: Herein, it was found that T-ICs, chemoresistance, and recurrent CRC samples all manifest increased PUM1 expression. Functional investigations have shown that PUM1 increased the self-renewal, tumorigenicity, malignant proliferation, and chemoresistance of colorectal cells. PUM1 activates the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signaling pathway biochemically. Furthermore, it was discovered that miR-218-5p specifically targets T-ICs' PUM1 3'-untranslated region (3'-UTR). More importantly, the PUM1/PI3K/AKT axis regulates CRC cells' responses to treatment with cetuximab, and PUM1 overexpression increased cetuximab resistance. More evidence points to the possibility that low PUM1 may predict cetuximab benefits in CRC patients after analysis of the patient cohort, patient-derived tumor organoids, and patient-derived xenografts (PDXs). Conclusions: Taken together, the result of this work points to the critical function of the miR-218-5p/PUM1/PI3K/AKT regulatory circuit in regulating T-ICs characteristics and thus suggests possible therapeutic targets for CRC.

Severe complications from anastomotic leakage after total mesorectal excision with the protective loop ileostomy in three patients.

INTRODUCTION AND IMPORTANCE: A protective loop ileostomy is recommended in ultra-low rectal cancer to reduce the complications associated with anastomotic leakage (AL), but there are few studies on the complications after AL. The purpose of this study was to outline our experience in the successful treatment of severe abdominal infection after AL in rectal cancer patients with the protective loop ileostomy. CASE PRESENTATION: In this report, we describe three cases of AL after standard total mesorectal excision with the protective loop ileostomy. Severe abdominal infection occurred postoperatively. The patients were successfully treated by surgical reintervention and had an uneventful recovery. No recurrence was observed after 2 years. CLINICAL DISCUSSION: We consider that pelvic floor reconstruction and extending the extubation time should be performed in patients with a high risk of AL. Moreover, when severe abdominal infection and early infectious shock occur after AL, immediate reoperation should be performed to minimize the complication. CONCLUSION: Protective loop ileostomy can't decrease the re-operation rate for patients with AL. We should take preventive measures during and after the operation, as well as early detection and early treatment.

Implementation of virtual reality technology to decrease patients' pain and nervousness during colonoscopies: a prospective randomised controlled single-blinded trial.

BACKGROUND: Improved patient satisfaction in endoscopy is worthy of study as it is an invasive and potentially uncomfortable procedure. There is growing literature on patient satisfaction assessment in endoscopy as part of improving quality assurance. This study aimed to determine whether virtual reality (VR) technology can decrease patients' pain and nervousness during colonoscopies. METHODS: Patients enrolled without sedation were randomly categorised into groups that watched VR (VR group; n=58) and those that did not watch VR (control group; n=59). The primary outcomes were pain score and skin conductance. Secondary endpoints included heart rate, systolic and diastolic arterial pressures, overall patient satisfaction, willingness to repeat the procedure, the difficulty of the procedure, the procedure duration, and bowel preparation. RESULTS: The median (interquartile range (IQR)) pain scores were 7 (6-8) and 5 (4-6) in the control and VR groups, respectively (p<0.001). The median (IQR) skin conductance values after colonoscope insertion were 0.660 (0.490-0.840) and 0.390 (0.280-0.600) in the control and VR groups, respectively (p<0.001). Overall, patient satisfaction was significantly improved with the use of VR, along with a significant reduction in the difficulty perceived by the endoscopist. CONCLUSION: VR technology helped to reduce patients' pain and nervousness and to improve patients' satisfaction during colonoscopies.

[Clinical efficacy of buzhong yiqi pill combined with imodium in treating post-operational diarrhea in patients of colonic cancer].

OBJECTIVE: To investigate the clinical efficacy of Buzhong Yiqi Pill (BYP) combined with imodium in treating post-operational diarrhea in patients undergoing colonic cancer surgery. METHODS: Eighty patients with diarrhea after colorectal cancer surgery were randomized into two groups equally, the control group were treated with imodium (loperamide hydrochloride) and the treatment group treated by BYP combined with imodium. The therapeutic efficacy was analyzed and evaluated comprehensively depending upon a defecation check table developed from the XU Zhong-fa's 5-item 10-integrable system. RESULTS: After treatment, the improvements of the anal controlling capacity, the defecatory sensation, the frequency of defecation in the treatment group were significantly better than those in the control group (P < 0.01 or P < 0.05). The integral function of defecation in the treatment group was obvionsly improved by the end of treatment when compared with before treatment and the control group (P < 0.01). CONCLUSION: The clinical efficacy of the BYP combined with imodium in treating post-operational diarrhea after colorectal cancer surgery were better than that of imodium alone.

High Tumor Vascular Endothelial Growth Factor Expression Is Associated With Poorer Clinical Outcomes in Resected T3 Gastric Adenocarcinoma.

OBJECTIVES: To investigate the clinical and prognostic significance of high vascular endothelial growth factor (VEGF) expression in resected T3 gastric adenocarcinoma (GA). METHODS: Data of VEGF expression on 453 patients with resected T3 GA were collected from a single institute in Fuzhou, China. VEGF expression in the resected tumor tissues was evaluated by immunohistochemistry (IHC). Associations between VEGF expression outcomes and prognosis were investigated using by the χ(2) test, Kaplan-Meier plus log-rank test, and univariate and multivariate Cox models. RESULTS: In total, 48.6% (220/453) patients had low VEGF expression (IHC score ≤2+). Patients with high VEGF expression (IHC>2+; 233/453, 51.4%) had significantly poorer median recurrence-free survival time (20 vs 55 months, P < 001) and median overall survival time (28 vs 58 months; P < 001) than patients with low VEGF. High VEGF was associated with higher overall recurrence (68.2% vs 51.4%, P = 2.675 × 10(-4)), poorer overall survival (27.5% vs 47.3%, P = 1.719 × 10(-5)), and increased risk of recurrence (hazard ratio [HR], 1.71; 95% confidence interval [CI], 1.33-2.19; P = 2.43 × 10(-5)) and death (HR, 1.80; 95% CI, 1.41-2.3; P = 2.19 × 10(-6)). CONCLUSIONS: High VEGF expression is associated with a higher risk of recurrence and shorter survival in resected T3 GA. These findings may provide a foundation for evaluating VEGF-targeted molecular therapies in T3 GA.

Aspirin, lysine, mifepristone and doxycycline combined can effectively and safely prevent and treat cancer metastasis: prevent seeds from gemmating on soil.

Recent scientific advances have increased our understanding of the cancer metastatic complexities and provided further impetus for new combination therapies to prevent cancer metastasis. Here, we demonstrated that a combination (HAMPT) of aspirin, lysine, mifepristone and doxycycline can effectively and safely prevent cancer metastasis. The pharmaceutically-formulated HAMPT inhibited adhesion of cancer cells to either endothelial cells or extracellular matrix via down-regulating cell adhesion molecules ICAM-1 and α4-integrin. HAMPT inhibited the cloak effect by activated platelets on cancer cells, thereby interfering adhesion and invasion of cancer cells to the underlying stroma. At the effective concentration, HAMPT induced cancer cells into dormancy with minor inhibition on cell viability. Four-day pretreatment followed by 30-day oral administration of HAMPT (33.5-134 mg/kg) to the mice inoculated with cancer cells produced significant inhibition on cancer metastasis dose-dependently without marked side effects. Fifty-day rat toxicity study with HAMPT at doses (335-1340 mg/kg) 20-fold higher than its therapeutic dose produced no significant toxicity. Interestingly, the acute toxic death could not be reached at the maximum administrable dose (5 g/kg). This proof-of-concept study provides the first conceptual evidence that cancer metastasis can be controlled by using affordable old drugs to restrain circulating tumor cells from gemmating on the metastatic soil without the need for cytotoxicity.

Mesenchymal stem cells improve intestinal integrity during severe acute pancreatitis.

Severe acute pancreatitis (SAP) is an acute inflammatory disease of the pancreas that involves various distant tissues and organs. This study aimed to investigate post-tissue injury repair by mesenchymal stem cells (MSCs) in a rat model of SAP. A total of 54 pathogen-free adult male SD rats were randomly assigned to the groups SAP, SAP + MSCs and sham-operated (SO). SAP was induced by 4% sodium taurocholate, and MSCs were injected via the dorsal penile vein 1 h later. The amylase activity, and tumor necrosis factor (TNF)-α and diamine oxidase (DAO) levels were measured with an enzyme-linked immunosorbent assay (ELISA), while the expression of aquaporin (AQP)-1 was evaluated by immunohistochemical staining. The pathological score of intestinal tissues was also compared among groups. Marked improvement in intestinal necrosis, villi shedding and infiltration of inflammatory cells was observed in the SAP + MSCs group compared to the SAP and SO groups. Amylase, TNF-α, and DAO levels were significantly increased in the SAP + MSCs group. The intestinal expression of AQP-1 was increased at 12 and 24 h post-MSC transplantation compared to the SO group. Rats of the SAP + MSCs group displayed higher pathological scores compared to the SAP group at all time points. Overall, these data showed that MSCs can inhibit systemic inflammation and reduce TNF-α release in a rat model of SAP-induced intestinal injury, suggesting that MSCs exert protective effects on the intestinal barrier during SAP.

Protective effect of transplanted bone marrow-derived mesenchymal stem cells on pancreatitis-associated lung injury in rats.

Severe acute pancreatitis (SAP) is initiated by the premature activation of digestive enzymes within the pancreatic acinar cells, leading to self-digestion and inflammatory responses in pancreatic ductal cells, thus giving rise to systemic inflammatory response syndrome (SIRS). The most common and serious SIRS is pancreatitis-associated lung injury, and inflammatory mediators play an important role in its pathogenesis. Bone marrow-derived mesenchymal stem cells (MSCs) are differentiated into alveolar endothelial cells to replace the damaged alveolar endothelial cells and inhibit inflammatory response in the injured lung tissues. In this study, we aimed to investigate the therapeutic effect of bone marrow-derived MSCs in rats with pancreatitis-associated lung injury. Experimental SAP was induced by a retrograde injection of 5% sodium taurocholate into the biliopancreatic duct of 75 male Sprague-Dawley rats, which were divided into the SAP group (n=25), the MSC group (n=25) and the sham-operated group (n=25) to explore the pathology and function of lung tissues and the regulation of inflammatory mediators. Pulmonary edema was estimated by measuring water content in the lung tissues. Pulmonary myeloperoxidase (MPO) activity was detected using spectrophotometry. Serum amylase was detected using the Automatic Biochemistry Analyzer. Tumor necrosis factor-α (TNF-α) and substance P (SP) mRNA levels were determined by quantitative reverse transcriptase-polymerase chain reaction. Our results showed that serum amylase activity was significantly decreased in the MSC group compared to the SAP group. Pulmonary edema was significantly diminished (p<0.05) in the MSC group compared to the SAP group. Typical acute lung injury was observed in the SAP group, and the pathological changes were mild in the MSC group. The expression of TNF-α and SP mRNA in lung tissue was diminished in the MSC group compared to the SAP group. In conclusion, MSC transplantation attenuates pulmonary edema and inflammation, and reduces the mRNA expression of TNF-α and SP in pancreatitis-associated lung injury.

Role of bone marrow-derived mesenchymal stem cells in a rat model of severe acute pancreatitis.

AIM: To investigate the role and potential mechanisms of bone marrow mesenchymal stem cells (MSCs) in severe acute peritonitis (SAP). METHODS: Pancreatic acinar cells from Sprague Dawley rats were randomly divided into three groups: non-sodium deoxycholate (SDOC) group (non-SODC group), SDOC group, and a MSCs intervention group (i.e., a co-culture system of MSCs and pancreatic acinar cells + SDOC). The cell survival rate, the concentration of malonaldehyde (MDA), the density of superoxide dismutase (SOD), serum amylase (AMS) secretion rate and lactate dehydrogenase (LDH) leakage rate were detected at various time points. In a separate study, Sprague Dawley rats were randomly divided into either an SAP group or an SAP + MSCs group. Serum AMS, MDA and SOD, interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α levels, intestinal mucosa injury scores and proliferating cells of small intestinal mucosa were measured at various time points after injecting either MSCs or saline into rats. In both studies, the protective effect of MSCs was evaluated. RESULTS: In vitro, The cell survival rate of pancreatic acinar cells and the density of SOD were significantly reduced, and the concentration of MDA, AMS secretion rate and LDH leakage rate were significantly increased in the SDOC group compared with the MSCs intervention group and the Non-SDOC group at each time point. In vivo, Serum AMS, IL-6, TNF-α and MAD level in the SAP + MSCs group were lower than the SAP group; however serum IL-10 level was higher than the SAP group. Serum SOD level was higher than the SAP group at each time point, whereas a significant between-group difference in SOD level was only noted after 24 h. Intestinal mucosa injury scores was significantly reduced and the proliferating cells of small intestinal mucosa became obvious after injecting MSCs. CONCLUSION: MSCs can effectively relieve injury to pancreatic acinar cells and small intestinal epithelium, promote the proliferation of enteric epithelium and repair of the mucosa, attenuate systemic inflammation in rats with SAP.

[Protective effect of N-acetylcysteine on the intestinal barrier dysfunction after radiation injury in rats].

OBJECTIVE: To evaluate the protective effect of N-acetylcysteine (NAC) on the intestinal barrier dysfunction in rats after extensive abdominal radiation with X ray. METHODS: Twenty-four Spraque-Dawley male rats were divided into normal control group (n=8), radiation group (n=8), and radiation+NAC group (300 mg/kg) (n=8). Radiation injury was induced by X ray with a single dose of 10 Gy. NAC was administered from 4 days before irradiation to 3 days after radiation. Three days after radiation, all the rats were euthanized. The terminal ileum was collected for crypt survival assay and ileal villi count. The tissue samples from mesenteric lymph nodes (MLN), spleen, and liver were harvested under sterile conditions for microbiological analysis and ileum samples were harvested for biochemical analysis. The blood levels of D-lactate, endotoxin and diamine oxidase (DAO) and the ileum samples levels of nitric oxide(NO) were also measured. RESULTS: Rats in radiation+NAC group had a higher survival rate of intestinal crypt [(76.84+/-4.82)% vs (49.64+/-5.48)%, P<0.01], higher intestinal villus count [(8.56+/-0.68)/mm vs (4.02+/-0.54)/mm, P<0.01], lower NO concentration [(0.48+/-0.12) mumol/g vs (0.88+/-0.16) mumol/g, P<0.01], lower levels of D-lactate, endotoxin and DAO (P<0.05 or P<0.01), and significantly decreased enteric bacteria cultured from mesenteric lymph nodes and other tissues as compared with the radiation group (P<0.05 or P<0.01). CONCLUSION: NAC protects the small intestine from radiation-induced injury maybe through the inhibition of NO in rats.