Intestinal barrier damage, systemic inflammatory response syndrome, and acute lung injury: A troublesome trio for acute pancreatitis

Influence of standardized nursing intervention combined with mindfulness stress reduction training on the curative effect in patients with acute pancreatitis

BACKGROUND

Acute pancreatitis (AP) is a common inflammatory disease of the pancreas with high mortality rates. It is of great significance to take scientific intervention measures for patients with AP in time.

AIM

To explore the effect of standardized nursing combined with mindfulness stress reduction training on the curative effect, negative emotion, and quality of life in patients with acute pancreatitis.

METHODS

A total of 80 patients with acute pancreatitis admitted to The First People's Hospital of Jiangxia District Hospital from May 2021 to May 2023 were randomly divided into control group and observation group (n = 40). Patients in control group were given the standardized nursing intervention, and the observation group were given standardized nursing plus mindfulness stress reduction training intervention. The time of clinical symptom disappeared or improved, complication occurrence rate, emotional state, and quality of life score of the two groups were observed and compared.

RESULTS

In comparison with the control group, the bowel sound recovery time, ventosity and abdominal pain improvement time, and venting and cacation time in observation group were shorter, and the total incidence rate of complications was reduced, showing statistically significant difference (P < 0.05). The scores of anxiety and depression in observation group were lower than those in control group (P < 0.05). Serum levels of tumour necrosis factor alpha, interleukin (IL)-6, IL-1β and IL-8 in observation group were lower than those in control group (P < 0.05). The scores of life quality in physiology, psychology, environment and social relations in observation group were higher than those in control group, and the differences were statistically significant (P < 0.05).

CONCLUSION

The application of standardized nursing intervention combined with mindfulness stress reduction training in patients with acute pancreatitis has a definite effect, which can help to ameliorate the clinical symptoms, anxiety and depression of patients, reduce the incidence rate of complications, and improve the prognosis of patients.

Single-Cell RNA Sequencing Reveals Roles of Fibroblasts During Intestinal Injury and Repair in Rats with Severe Acute Pancreatitis

Purpose

To explore the molecular mechanisms of intestinal injury and treatment by analyzing changes in cellular heterogeneity and composition in rat ileal tissue during injury and treatment processes.

Methods

We constructed a rat model of SAP and evaluated treatment with an injected of monoacylglycerol lipase (MAGL) inhibitor (JZL184) solution using three experimental groups: healthy male Sprague-Dawley (SD) rats injected with vehicle (CON), male SD SAP model rats injected with vehicle (SAP), and male SAP rats injected with JZL184. We obtained and prepared a single-cell suspension of ileal tissue of each rat for single-cell transcriptome sequencing.

Results

This project classified changes in cellular heterogeneity and composition in rat ileal tissue during SAP-induced intestinal injury and MAGL treatment. We found that the number of fibroblast clusters was decreased in the SAP group relative to the CON group, and increased after JZL184 treatment. Further analysis of differences in gene expression between cell clusters in each group reveals that fibroblasts had the greatest number of differentially expressed genes. Most notably, expression of genes involved in communication between cells was found to vary during SAP-induced intestinal injury and JZL184 treatment. Among these changes, the degree of difference in expression of genes involved in communication between fibroblasts and other cells was the highest, indicating that fibroblasts in rat ileal tissue affect intestinal injury and repair through cell-to-cell communication. In addition, our results reveal that differentially expressed RNA-binding proteins in fibroblasts may affect their functions in intestinal injury and treatment by affecting the expression of genes regulating communication between cells.

Conclusion

These findings emphasize the importance of understanding the interactions between fibroblasts and other cells in the context of intestinal injury, providing valuable insights for further exploring molecular mechanisms and insight for discovering new treatment targets and strategies.

High-density lipoprotein cholesterol level as an independent protective factor against aggravation of acute pancreatitis: a case-control study

Background and aims

At present, evidence on the association between high-density lipoprotein cholesterol (HDL-C) levels and aggravation of acute pancreatitis (AP) is limited. This study aimed to investigate the relationship between the lowest HDL-C level during intensive care units (ICU) stay and AP aggravation and to determine the optimum cutoff lowest HDL-C level.

Methods

Patients admitted to the ICU of the Shandong Provincial Hospital for AP from 2015 to 2021 were included. The lowest HDL-C level during ICU stay was set as the independent variable, and the progression or non-progression to severe AP (SAP) was set as the dependent variable. Univariate and multivariate analyses were performed to determine the relationship between the two variables, and receiver operating characteristic (ROC) curves were plotted to analyze the predictive ability of the lowest HDL-C level for progression to SAP.

Results

This study included 115 patients. The difference in the lowest HDL-C level between the SAP and moderately SAP groups was significant (P < 0.05). After adjusting for covariates, the lowest HDL-C level showed a negative correlation with the occurrence of SAP, with a relative risk of 0.897 (95% confidence interval: 0.827-0.973). The area under the ROC curve for prediction of AP aggravation by the lowest HDL-C level was 0.707, and the optimum cutoff lowest HDL-C level was 0.545 mmol/L.

Conclusion

No less than 0.545 mmol/L of the HDL-C level during ICU stay may be an independent protective factor for the aggravation of AP.

Eliminating COVID-19 as the immediate culprit for igniting pancreatitis

The impact of severe acute respiratory syndrome coronavirus 2 infection on the potential development of pancreatitis is a subject of ongoing debate within academic discourse. Establishing a causal link between COVID-19 and pancreatitis may not be fully supported by relying only on retrospective studies or case reports. This study examined the relationship between COVID-19 phenotypes and pancreatitis by Mendelian randomization (MR) method. The identification of instrumental variables (single nucleotide polymorphisms) that exhibit a robust association with the COVID-19 phenotypes was accomplished through a meticulous process of rigorous screening procedures. We included acute pancreatitis and chronic pancreatitis (CP) as the outcomes in the MR analysis, even though no definitive studies exist between COVID-19 and CP. A direct causal relationship between genetically predicted COVID-19 phenotypes and pancreatitis risk cannot be established. There is an ongoing debate over the designation of COVID-19 as a definitive cause of pancreatitis.

Da-Cheng-Qi decoction improves severe acute pancreatitis-associated acute lung injury by interfering with intestinal lymphatic pathway and reducing HMGB1-induced inflammatory response in rats

CONTEXT

Da-Cheng-Qi Decoction (DCQD) has a significant effect on Severe Acute Pancreatitis-Associated Acute Lung Injury (SAP-ALI).

OBJECTIVE

To explore the mechanism of DCQD in the treatment of SAP-ALI based on intestinal barrier function and intestinal lymphatic pathway.

MATERIALS AND METHODS

Forty-five Sprague-Dawley rats were divided into three groups: sham operation, model, and DCQD. The SAP model was induced by a retrograde infusion of 5.0% sodium taurocholate solution (1 mg/kg) at a constant rate of 12 mL/h using an infusion pump into the bile-pancreatic duct. Sham operation and model group were given 0.9% normal saline, while DCQD group was given DCQD (5.99 g/kg/d) by gavage 1 h before operation and 1, 11 and 23 h after operation. The levels of HMGB1, RAGE, TNF-α, IL-6, ICAM-1, d-LA, DAO in blood and MPO in lung were detected using ELISA. The expression of HMGB1, RAGE, NF-κB p65 in mesenteric lymph nodes and lung were determined.

RESULTS

Compared with SAP group, DCQD significantly reduced the histopathological scoring of pancreatic tissue (SAP, 2.80 ± 0.42; DCQD, 2.58 ± 0.52), intestine (SAP, 3.30 ± 0.68; DCQD, 2.50 ± 0.80) and lung (SAP, 3.30 ± 0.68; DCQD, 2.42 ± 0.52). DCQD reduced serum HMGB1 level (SAP, 134.09 ± 19.79; DCQD, 88.05 ± 9.19), RAGE level (SAP, 5.05 ± 1.44; DCQD, 2.13 ± 0.54). WB and RT-PCR showed HMGB1-RAGE pathway was inhibited by DCQD (p < 0.01).

DISCUSSION AND CONCLUSIONS

DCQD improves SAP-ALI in rats by interfering with intestinal lymphatic pathway and reducing HMGB1-induced inflammatory response.

Emodin Ameliorates Severe Acute Pancreatitis-Associated Acute Lung Injury in Rats by Modulating Exosome-Specific miRNA Expression Profiles

Background

Numerous preclinical investigations have exhibited the beneficial impact of emodin (EMO) on the management of severe acute pancreatitis (SAP)-associated acute lung injury (ALI). However, the potential of EMO to mitigate organ damage through the modulation of exosome (Exo)-specific miRNA expression profiles remains unclear.

Methods

The SAP rat model was established by retrograde injection of 5% sodium taurocholate into the pancreatic bile duct. Rats received intragastric administration of EMO at 2 h and 12 h post-modeling. Plasma and bronchoalveolar lavage fluid (BALF)-derived exosomes were isolated and purified from SAP rats treated with EMO. The therapeutic effects of these Exos in SAP rats were assessed using hematoxylin-eosin staining and measurement of inflammatory factor levels. MicroRNA (miRNA) sequencing was conducted on plasma and BALF-derived Exos, and rescue experiments were performed to investigate the function of NOVEL miR-29a-3p in the treatment of SAP using EMO.

Results

EMO exhibits ameliorative effects on pancreatic and lung injury and inflammation in rats with SAP. Plasma/BALF-derived Exos from EMO-treated SAP rats also have therapeutic effects on SAP rats. The miRNA expression profile of plasma and BALF-derived Exos in SAP rats underwent significant changes upon exposure to EMO. In particular, 34 differentially expressed miRNAs (DEmiRNAs) were identified when comparing BALF-SAP+EMO-Exo and BALF-SAP-Exo. 39 DEmiRNAs were identified when comparing plasma-SAP+EMO-Exo to plasma-SAP-Exo. We found that SAP rats treated with Exos derived from BALF exhibited a more potent therapeutic response than those treated with Exos derived from plasma. EMO may rely on NOVEL-rno-miR-29a-3p expression to prevent pulmonary injury in SAP rats.

Conclusion

The mechanism of action of EMO is observed to have a significant impact on the miRNA expression profile of Exos derived from plasma and BALF in SAP rats. NOVEL-rno-miR-29a-3p, which is specific to Exos, and is derived from BALF, may play a crucial role in the therapeutic efficacy of EMO.

Kaempferitrin alleviates LPS-induced septic acute lung injury in mice through downregulating NF-κB pathway

BACKGROUND

Acute lung injury (ALI) causes severe and uncontrolled pulmonary inflammation and has high morbidity in dying patients.

OBJECTIVE

This study aimed to evaluate the potential function of Kaempferitrin (Kae) and uncover its mechanisms in ALI.

MATERIAL AND METHODS

We evaluated the role of Kae in ALI through the lipopolysaccharide (LPS)-induced histopathological changes, lung wet/dry (W/D) ratio, total bronchoalveolar lavage fluid (BALF) cells count, pulmonary inflammation, and the levels of interleukin (IL)-6, tumor necrosis factor-α (TNF-α), and IL-1β. The effect of Kae on NF-κB signaling pathway was discovered through the protein expression levels of transcription factors p65, p-p65, IκBα, and p-IκBα by Western blot analysis.

RESULTS

The results showed that Kae could improve lung injury by reducing apoptosis, histopathological changes, and lung W/D ratio; more importantly, Kae enhanced the survival of ALI mice. Moreover, Kae relieved inflammation, as it reduced total BALF cells count, and deceased the levels of TNF-α, IL-6, and IL-1β in serum. In addition, Western blot analysis data suggested that Kae could decrease the protein expression levels of transcription factors p65, p-p65, IκB-α, and p-IκB-α, which were promoted by LPS.

CONCLUSION

The results of this study suggested that Kae could relieve LPS-induced ALI in mice and reduce inflammation and apoptosis through NF-κB pathway.

Lidocaine ameliorates intestinal barrier dysfunction in irritable bowel syndrome by modulating corticotropin-releasing hormone receptor 2

BACKGROUND

Intestinal barrier dysfunction is a prevalent pathogenic factor underlying various disorders. Currently there is no effective resolution. Previous studies have reported the potential anti-inflammatory properties of lidocaine and its ability to alleviate visceral hypersensitivity in individuals with irritable bowel syndrome (IBS). Therefore, our study will further verify the effect of lidocaine on intestinal barrier dysfunction in IBS and investigate the underlying mechanisms.

METHODS

In this study, we investigated the role of lidocaine by assessing visceral hypersensitivity, body weight, inflammatory factors, fluorescein isothiocyanate-dextran 4000 (FD4) flux, tight junctions (TJs) and spleen and thymus index in rats subjected to water avoidance stress (WAS) to mimic intestinal barrier dysfunction in IBS with and without lidocaine. In vitro, we investigated the role of corticotropin-releasing hormone receptor 2 (CRHR2) in lidocaine-treated Caco2 cells using small interfering RNA (siRNA) targeting CRHR2.

KEY RESULTS

In WAS rats, lidocaine significantly restored weight loss, damaged TJs, spleen index and thymus index and inhibited abdominal hypersensitivity as well as blood levels of markers indicating intestinal permeability, such as diamine oxidase (DAO), D-lactic acid (D-Lac) and lipopolysaccharide (LPS). Consequently, the leakage of FD4 flux from intestine was significantly attenuated in lidocaine group, and levels of intestinal inflammatory factors (IL-1β, IFN-γ, TNF-α) were reduced. Interestingly, lidocaine significantly suppressed corticotropin-releasing hormone (CRH) levels in lamina propria cells, while the CRH receptor CRHR2 was upregulated in intestinal epithelial cells. In vitro, lidocaine enhanced the expression of CRHR2 on Caco-2 intestinal epithelial cells and restored disrupted TJs and the epithelial barrier caused by LPS. Conversely, these effects were diminished by a CRHR2 antagonist and siRNA-CRHR2, suggesting that the protective effect of lidocaine depends on CRHR2.

CONCLUSIONS AND INFERENCES

Lidocaine ameliorates intestinal barrier dysfunction in IBS by potentially modulating the expression of CRHR2 on intestinal epithelial cells.

Diagnosis and Contemporary Management of Necrotizing Pancreatitis

BACKGROUND

Acute pancreatitis is a common diagnosis which requires a prompt diagnosis and management by a multidisciplinary team with often general surgeons as the initial provider. Morbidity and mortality from an acute pancreatitis can be very high, especially in patients with a progressive worsening acute pancreatitis developing into pancreatic necrosis in the setting of multiple underlying medical comorbidities.

PURPOSE

In this review paper, we discuss all aspects of acute pancreatitis and its potential complications, as well providing updates in the modern management of necrotizing pancreatitis. Practicing general surgeons need to be aware of the evolution in the diagnosis and treatment of this disease.

RESEARCH DESIGN

We conducted a review of literature of evidence and management options for acute pancreatitis, including all published manuscripts from 2012 to 2022.

RESULTS

Diagnosis and management of this disease can vary among specialiaties. The decision to utilize a percutaneous or endoscopic techniques are relevant points of discussion within general surgery and gastroenterology societies. In the past decade, the use of advanced endoscopic interventions has slowly replaced conventional open surgery in managing complications of acute severe pancreatitis.

CONCLUSION

Acute pancreatitis is a disease which requires multidisciplinary approach with evolving treatment options to less invasive nonsurgical methods.

Sirtuin4 alleviates severe acute pancreatitis by regulating HIF-1α/HO-1 mediated ferroptosis

Acute pancreatitis (AP) is a common emergency of the digestive system and serious cases can develop into severe acute pancreatitis (SAP), which ortality rates up to 30%. Sirtuin4 (SIRT4) is a member of the sirtuin family, and plays a key role in inflammation and oxidative stress. However, the potential role of SIRT4 in SAP has yet to be elucidated. In the present study, we found that the expression level of SIRT4 in human AP was downregulated by screening a public database, suggesting that SIRT4 may play a role in AP. Subsequently, we used L-arginine (L-Arg) to induce SAP in SIRT4 knockout (SIRT4_KO) and SIRT4 overexpression (AAV_SIRT4) mice. The results showed that the pancreatic tissue injury and related lung and kidney injury were serious in SIRT4_KO mice after SAP induction, but were significantly reduced in AAV_SIRT4 mice. More importantly, we found that the levels of antioxidant factors GSH and SOD were decreased in SIRT4_KO mice, and the production of oxidative products and lipid peroxidation markers was increased, suggesting that SIRT4 was involved in inflammation and oxidative stress during SAP. Further studies showed that the absence or overexpression of SIRT4 affected the expression level of Hypoxia-inducible factor-1α (HIF-1α) after SAP induction, and regulated the expression of ferroptosis related proteins by mediating HIF-1α/HO-1 pathway. Collectively, our study revealed that SIRT4 plays a protective role in SAP by regulating the HIF-1α/HO-1 pathway to inhibit ferroptosis.

Anti-inflammatory effects of probiotics and synbiotics on patients with non-alcoholic fatty liver disease: An umbrella study on meta-analyses

BACKGROUND AND AIM

The impact of chronic low-grade inflammation in the development of non-alcoholic fatty liver disease (NAFLD) has been studied widely. Previous studies showed gut pathogens' effects on inflammation development in NAFLD patients; hence, hypothetically, gut microbial therapy by administration of probiotics, synbiotics, and prebiotics may alleviate inflammation in these individuals. Several studies were performed in this regard; however, conflicting results were obtained. In this study, we aimed to comprehensively evaluate the effects of gut microbial therapy on inflammatory markers in NAFLD patients in a meta-umbrella design.

METHODS

Two independent researchers investigated international databases, including PubMed, Web of Science, Scopus, and Cochrane Library, from inception until March 2023. Meta-analyses evaluating the impact of probiotics, synbiotics, or prebiotics on inflammatory markers of patients with NAFLD were eligible for our study. AMASTAR 2 checklist was used to evaluate the quality of included studies. Random effect model was performed for the analysis, and Egger's regression test was conducted to determine publication bias.

RESULTS

A total number of 12 studies were entered into our analysis. Our findings revealed that gut microbial therapy could significantly reduce serum C-reactive protein (CRP) levels among NAFLD patients (ES: -0.58; 95% CI: -0.73, -0.44, P < 0.001). In subgroup analysis, this reduction was observed with both probiotics (ES: -0.63; 95% CI: -0.81, -0.45, P < 0.001) and synbiotics (ES: -0.49; 95% CI: -0.74, -0.24, P < 0.001). In addition, gut microbial therapy could significantly decrease tumor necrosis factor-a (TNF-a) levels in NAFLD patients (ES: -0.48; 95% CI: -0.67 to -0.30, P < 0.001). In subgroup analysis, this decrease was observed with probiotics (ES: -0.32; 95% CI: -0.53, -0.11, P = 0.002) and synbiotics (ES: -0.96; 95% CI: -1.32, -0.60, P < 0.001). Not enough information was available for assessing prebiotics' impacts.

CONCLUSION

The results of this umbrella review suggest that probiotics and synbiotics have promising effects on inflammatory markers, including TNF-a and CRP; however, more research is needed regarding the effects of prebiotics.

PROSPERO REGISTRATION CODE

CRD42022346998.

Role and mechanism of ferroptosis in acute lung injury

Ferroptosis is a new non-apoptotic cell death caused by the accumulation of dysregulated metabolism of ferric iron, amino acids or lipid peroxidation. Increasing studies suggest that ferroptosis is involved in the acute lung injury (ALI). This article aims to review the role of ferroptosis in ALI. ALI is a common respiratory disease and presents a high mortality rate. Inhibiting cell ferroptosis of lung improves the ALI. In addition, several signaling pathways are related to ferroptosis in ALI, involving in iron homeostasis, lipid peroxidation, and amino acid metabolism. Moreover, there are various key factors to regulate the occurrence of ferroptosis in ALI, such as ACSL4, NRF2, and P53. The ACSL4 promotes the ferroptosis, while the NRF2 alleviates the ferroptosis in ALI. The main effect of P53 is to promote ferroptosis. Accordingly, ferroptosis is involved in ALI and may be an important therapeutic target for ALI.

The Role and Potential Regulatory Mechanism of STING Modulated Macrophage Apoptosis and Differentiation in Severe Acute Pancreatitis-Associated Lung Injury

This study aims to investigate the role of STING in promoting macrophage apoptosis and regulating macrophage polarization in severe acute pancreatitis (SAP)-associated lung injury in vitro and in vivo. A murine model was established by intraperitoneal injection of caerulein and lipopolysaccharide (LPS). Meanwhile, ANA-1 cells were stimulated with LPS to induce apoptosis in vitro. More primary alveolar macrophages underwent apoptosis and M1 macrophage polarization in the SAP group compared with the control group, which was reversed by inhibiting STING. When ANA-1 cells were induced into M2-type macrophages, the reduction of M1 macrophage markers was accompanied by a decrease of LPS-induced apoptosis. Finally, the inhibitory effect of C-176 on STING ameliorates lung injury and inflammation by adjusting macrophage polarization and rescuing apoptosis. Therefore, inhibiting STING could be a new therapeutic strategy for treating acute pancreatitis-associated lung injury.

Multi-omics approach to socioeconomic disparity in metabolic syndrome reveals roles of diet and microbiome

The epidemy of metabolic syndrome (MetS) is typically preceded by adoption of a "risky" lifestyle (e.g., dietary habit) among populations. Evidence shows that those with low socioeconomic status (SES) are at an increased risk for MetS. To investigate this, we recruited 123 obese subjects (body mass index [BMI] ≥ 30) from Chicago. Multi-omic data were collected to interrogate fecal microbiota, systemic markers of inflammation and immune activation, plasma metabolites, and plasma glycans. Intestinal permeability was measured using the sugar permeability testing. Our results suggest a heterogenous metabolic dysregulation among obese populations who are at risk of MetS. Systemic inflammation, linked to poor diet, intestinal microbiome dysbiosis, and gut barrier dysfunction may explain the development of MetS in these individuals. Our analysis revealed 37 key features associated with increased numbers of MetS features. These features were used to construct a composite metabolic-inflammatory (MI) score that was able to predict progression of MetS among at-risk individuals. The MI score was correlated with several markers of poor diet quality as well as lower levels of gut microbial diversity and abnormalities in several species of bacteria. This study reveals novel targets to reduce the burden of MetS and suggests access to healthy food options as a practical intervention.

Activation of AMPK ameliorates acute severe pancreatitis by suppressing pancreatic acinar cell necroptosis in obese mice models

Obese people with acute pancreatitis (AP) have an increased risk of developing severe acute pancreatitis (SAP), which prolongs the length of hospital stay and increases mortality. Thus, elucidation of the mechanisms through which SAP occurs in obese individuals will provide clues for possible treatment targets. Differences in early events in obese or lean patients with AP have not been conclusively reported. We selected C57BL/6 mice as lean mice models, ob/ob mice or diet induced obese (DIO) mice as obese mice models and then induced experimental AP in mice via injections of caerulein. There were suppressed p-AMPK expressions in the pancreas of obese mice, compared with same-age lean C57BL/6 mice, which were further reduced in AP mice models. Obese AP mice were treated using AICAR, a direct AMPK agonist, which prevented pancreatic damage and cell death, suppressed pancreatic enzyme levels in serum, reduced the areas of fat saponification in the peritoneal cavity, prevented injury in other organs and decreased mice mortality rate. Further assays showed that AICAR activates p-AMPK to stabilize pro-caspase-8. Pro-caspase-8 enhances RIPK3 degradation, inhibits pancreatic acinar cell necroptosis, and downregulates the release of pancreatic enzymes. Thus, activation of AMPK by AICAR alleviates pancreatic acinar cell necroptosis and converts SAP to mild acute pancreatitis in obese mice.

Development of a predictive nomogram for acute respiratory distress syndrome in patients with acute pancreatitis complicated with acute kidney injury

BACKGROUND

Acute respiratory distress syndrome (ARDS) is a common complication in patients with acute pancreatitis (AP), especially when patients complicated with acute kidney injury (AKI), resulting in increased duration of hospitalization and mortality. It is of potential clinical significance to develop a predictive model to identify the the high-risk patients.

METHOD

AP patients complicated with AKI from January 2019 to March 2022 were enrolled in this study and randomly divided into training cohort and validation cohort at a ratio of 2:1. The Least absolute shrinkage and selection operator(LASSO) regression and machine learning algorithms were applied to select features. A nomogram was developed based on the multivariate logistic regression. The performance of the nomogram was evaluated by AUC, calibration curves, and decision curve analysis.

RESULTS

A total of 292 patients were enrolled in the study, with 206 in the training cohort and 86 in the validation cohort. Multivariate logistic analysis showed that IAP (Odds Ratio (OR)=4.60, 95%CI:1.23-18.24, p = 0.02), shock (OR = 12.99, 95%CI:3.47-64.04, p < 0.001), CRP(OR= 26.19, 95%CI:9.37-85.57, p < 0.001), LDH (OR = 13.13, 95%CI:4.76-40.42, p < 0.001) were independent predictors of ARDS. The nomogram was developed based on IAP, shock, CRP and LDH. The nomogram showed good discriminative ability with an AUC value of 0.954 and 0.995 in the training and validation cohort, respectively. The calibration curve indicating good concordance between the predicted and observed values. The DCA showed favorable net clinical benefit.

CONCLUSION

This study developed a simple model for predicting ARDS in AP patients complicated with AKI. The nomogram can help clinicians identify high-risk patients and optimize therapeutic strategies.

Mechanisms of Qingyi Decoction in Severe Acute Pancreatitis-Associated Acute Lung Injury via Gut Microbiota: Targeting the Short-Chain Fatty Acids-Mediated AMPK/NF-κB/NLRP3 Pathway

The pivotal roles of gut microbiota in severe acute pancreatitis-associated acute lung injury (SAP-ALI) are increasingly revealed, and recent discoveries in the gut-lung axis have provided potential approaches for treating SAP-ALI. Qingyi decoction (QYD), a traditional Chinese medicine (TCM), is commonly used in clinical to treat SAP-ALI. However, the underlying mechanisms remain to be fully elucidated. Herein, by using a caerulein plus lipopolysaccharide (LPS)-induced SAP-ALI mice model and antibiotics (Abx) cocktail-induced pseudogermfree mice model, we tried to uncover the roles of the gut microbiota by administration of QYD and explored its possible mechanisms. Immunohistochemical results showed that the severity of SAP-ALI and intestinal barrier functions could be affected by the relative depletion of intestinal bacteria. The composition of gut microbiota was partially recovered after QYD treatment with decreased Firmicutes/Bacteroidetes ratio and increased relative abundance in short-chain fatty acids (SCFAs)-producing bacteria. Correspondingly increased levels of SCFAs (especially propionate and butyrate) in feces, gut, serum, and lungs were observed, generally consistent with changes in microbes. Western-blot analysis and RT-qPCR results indicated that the AMPK/NF-κB/NLRP3 signaling pathway was activated after oral administration of QYD, which was found to be possibly related to the regulatory effects on SCFAs in the intestine and lungs. In conclusion, our study provides new insights into treating SAP-ALI through modulating the gut microbiota and has prospective practical value for clinical use in the future. IMPORTANCE Gut microbiota affects the severity of SAP-ALI and intestinal barrier function. During SAP, a significant increase in the relative abundance of gut pathogens (Escherichia, Enterococcus, Enterobacter, Peptostreptococcus, Helicobacter) was observed. At the same time, QYD treatment decreased pathogenic bacteria and increased the relative abundance of SCFAs-producing bacteria (Bacteroides, Roseburia, Parabacteroides, Prevotella, Akkermansia). In addition, The AMPK/NF-κB/NLRP3 pathway mediated by SCFAs along the gut-lung axis may play an essential role in preventing the pathogenesis of SAP-ALI, which allows for reduced systemic inflammation and restoration of the intestinal barrier.

Inhibition of angiotensin II type 1 receptor reduces oxidative stress damage to the intestinal barrier in severe acute pancreatitis

Intestinal barrier injury is a common complication of severe acute pancreatitis (SAP), which is often accompanied by intestinal mucosal barrier injury and results in serious consequences. However, the exact mechanism remains unclear. We aimed to investigate whether angiotensin II type 1 receptor (AT1)-mediated oxidative stress is involved in SAP intestinal barrier injury and assessed the effects of inhibiting this pathway. The SAP model was established by retrograde bile duct injection of sodium taurocholate (5%). The rats were divided into three groups: the control group (SO), the SAP group (SAP), and the azilsartan intervention group (SAP + AZL). Serum amylase, lipase, and other indexes were measured to evaluate SAP severity in each group. Histopathological changes in the pancreas and intestine were evaluated by HE staining. The oxidative stress of intestinal epithelial cells was detected by superoxide dismutase and glutathione. We also detected the expression and distribution of intestinal barrier-related proteins. The results showed that the serum indexes, the severity of tissue damage, and the level of oxidative stress in the SAP + AZL group were significantly lower than in the SAP group. Our study provided hitherto undocumented evidence of AT1 expression in the intestinal mucosa, confirming that AT1-mediated oxidative stress is involved in SAP intestinal mucosal injury, and inhibiting this pathway could effectively reduce intestinal mucosal oxidative stress injury, providing a new and effective target for the treatment of SAP intestinal barrier injury.

Glucocorticoid Treatment in Acute Respiratory Distress Syndrome: An Overview on Mechanistic Insights and Clinical Benefit

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS), triggered by various pathogenic factors inside and outside the lungs, leads to diffuse lung injury and can result in respiratory failure and death, which are typical clinical critical emergencies. Severe acute pancreatitis (SAP), which has a poor clinical prognosis, is one of the most common diseases that induces ARDS. When SAP causes the body to produce a storm of inflammatory factors and even causes sepsis, clinicians will face a two-way choice between anti-inflammatory and anti-infection objectives while considering the damaged intestinal barrier and respiratory failure, which undoubtedly increases the difficulty of the diagnosis and treatment of SAP-ALI/ARDS. For a long time, many studies have been devoted to applying glucocorticoids (GCs) to control the inflammatory response and prevent and treat sepsis and ALI/ARDS. However, the specific mechanism is not precise, the clinical efficacy is uneven, and the corresponding side effects are endless. This review discusses the mechanism of action, current clinical application status, effectiveness assessment, and side effects of GCs in the treatment of ALI/ARDS (especially the subtype caused by SAP).

The role of artificial neural networks in prediction of severe acute pancreatitis associated acute respiratory distress syndrome: A retrospective study

Early identification and intervention of acute respiratory distress syndrome (ARDS) are particularly important. This study aimed to construct predictive models for ARDS following severe acute pancreatitis (SAP) by artificial neural networks and logistic regression. The artificial neural networks model was constructed using clinical data from 214 SAP patients. The patient cohort was randomly divided into a training set and a test set, with 149 patients allocated to the training set and 65 patients assigned to the test set. The artificial neural networks and logistic regression models were trained by the training set, and then the performance of both models was evaluated using the test set. The sensitivity, specificity, PPV, NPV, accuracy, and AUC value of artificial neural networks model were 68.0%, 87.5%, 77.3%, 81.4%, 80.0%, 0.853 ± 0.054 (95% CI: 0.749-0.958). The sensitivity, specificity, PPV, NPV, accuracy and AUC value of logistic regression model were 48.7%, 85.3%, 65.5%, 74.4%, 72.0%, 0.799 ± 0.045 (95% CI: 0.710-0.888). There were no significant differences between the artificial neural networks and logistic regression models in predictive performance. Bedside Index of Severity in Acute Pancreatitis score, procalcitonin, prothrombin time, and serum calcium were the most important predictive variables in the artificial neural networks model. The discrimination abilities of logistic regression and artificial neural networks models in predicting SAP-related ARDS were similar. It is advisable to choose the model according to the specific research purpose.

Colonic mucin-2 attenuates acute necrotizing pancreatitis in rats by modulating intestinal homeostasis

Mucin-2 (MUC2) secreted by goblet cells participates in the intestinal barrier, but its mechanism in acute necrotizing pancreatitis (ANP) remains unclear. In acute pancreatitis (AP) patients, the functions of goblet cells (MUC2, FCGBP, CLCA1, and TFF3) decreased, and MUC2 was negatively correlated with AP severity. ANP rats treated with pilocarpine (PILO) (PILO+ANP rats) to deplete MUC2 showed more serious pancreatic and colonic injuries, goblet cell dysfunction, gut dysbiosis, and bacterial translocation than those of ANP rats. GC-MS analysis of feces showed that PILO+ANP rats had lower levels of butyric acid, isobutyric acid, isovaleric acid, and hexanoic acid than those of ANP rats. The expression of MUC2 was associated with colonic injury and gut dysbiosis. All these phenomena could be relieved, and goblet cell functions were also partially reversed by MUC2 supplementation in ANP rats. TNF-α-treated colonoids had exacerbated goblet cell dysfunction. MUC2 expression was negatively correlated with the levels of pro-inflammatory cytokines (IL-1β and IL-6) (p < .05) and positively related to the expression of tight junction proteins (Claudin 1, Occludin, and ZO1) (p < .05). Downregulating MUC2 by siRNA increased the levels of the pro-inflammatory cytokines in colonoids. MUC2 might maintain intestinal homeostasis to alleviate ANP.

Administration of Warfarin Inhibits the Development of Cerulein-Induced Edematous Acute Pancreatitis in Rats

Acute pancreatitis (AP) is a severe disease with high morbidity and mortality in which inflammation and coagulation play crucial roles. The development of inflammation leads to vascular injury, endothelium and leukocytes stimulation, and an increased level of tissue factor, which results in the activation of the coagulation process. For this reason, anticoagulants may be considered as a therapeutic option in AP. Previous studies have shown that pretreatment with heparin, low-molecular-weight heparin (LMWH), or acenocoumarol inhibits the development of AP. The aim of the present study was to check if pretreatment with warfarin affects the development of edematous pancreatitis evoked by cerulein. Warfarin (90, 180, or 270 µg/kg/dose) or saline were administered intragastrically once a day for 7 days consecutively before the induction of AP. AP was evoked by the intraperitoneal administration of cerulein. The pre-administration of warfarin at doses of 90 or 180 µg/kg/dose reduced the histological signs of pancreatic damage in animals with the induction of AP. Additionally, other parameters of AP, such as an increase in the serum activity of lipase and amylase, the plasma concentration of D-dimer, and interleukin-1β, were decreased. In addition, pretreatment with warfarin administered at doses of 90 or 180 µg/kg/dose reversed the limitation of pancreatic blood flow evoked by AP development. Warfarin administered at a dose of 270 µg/kg/dose did not exhibit a preventive effect in cerulein-induced AP. Conclusion: Pretreatment with low doses of warfarin inhibits the development of AP evoked by the intraperitoneal administration of cerulein.

Effects of probiotics on pancreatic inflammation and intestinal integrity in mice with acute pancreatitis

BACKGROUND

Severe acute pancreatitis is a potentially life-threatening disease. Despite being a common disorder, acute pancreatitis lacks a specific treatment. The present study aimed to examine the effects of probiotics on pancreatic inflammation and intestinal integrity in mice with acute pancreatitis.

METHODS

Male ICR mice were randomly divided into 4 groups (n = 6 per group). The control group received two intraperitoneal (i.p.) injections of normal saline as a vehicle control. The acute pancreatitis (AP) group received two i.p. injections of L-arginine 450 mg/100 g body weight. AP plus probiotics groups received L-arginine to induce acute pancreatitis as above. In the single-strain and mixed-strain groups, mice received 1 mL of Lactobacillus plantarum B7 1 × 10⁸ CFU/mL and 1 mL of Lactobacillus rhamnosus L34 1 × 10⁸ CFU/mL and Lactobacillus paracasei B13 1 × 10⁸ CFU/mL by oral gavage, respectively for 6 days starting 3 days prior to the AP induction. All mice were sacrificed 72 h after L-arginine injection. Pancreatic tissue was obtained for histological evaluation and immunohistochemical studies for myeloperoxidase, whereas ileal tissue was used for immunohistochemical studies for occludin, and claudin-1. Blood samples were collected for amylase analysis.

RESULTS

Serum amylase levels and pancreatic myeloperoxidase levels in the AP group were significantly higher than in controls and significantly decreased in probiotic groups compared with the AP group. Ileal occludin and claudin-1 levels were significantly lower in the AP group than in controls. Ileal occludin levels significantly increased, whereas ileal claudin-1 levels did not significantly change in both probiotic groups as compared with the AP group. The pancreatic histopathology showed significantly higher degree of inflammation, edema, and fat necrosis in the AP group, and these changes improved in mixed-strained probiotic groups.

CONCLUSIONS

Probiotics, particularly the mixed-strain ones, attenuated AP via the reduction of inflammation and the maintenance of intestinal integrity.

Aggressive versus controlled fluid resuscitation in acute pancreatitis: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Early fluid resuscitation is one of the fundamental treatments for acute pancreatitis (AP), but there is no consensus on the optimal fluid rate. This systematic review and meta-analysis aimed to compare the efficacy and safety of aggressive vs. controlled fluid resuscitation (CFR) in AP.

METHODS

The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and Web of Science databases were searched up to September 30, 2022, for randomized controlled trials (RCTs) comparing aggressive with controlled rates of early fluid resuscitation in AP patients without organ failure on admission. The following keywords were used in the search strategy: "pancreatitis," "fluid therapy,""fluid resuscitation,"and "randomized controlled trial." There was no language restriction. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework was used to assess the certainty of evidence. Trial sequential analysis (TSA) was used to control the risk of random errors and assess the conclusions.

RESULTS

A total of five RCTs, involving 481 participants, were included in this study. For primary outcomes, there was no significant difference in the development of severe AP (relative risk [RR]: 1.87, 95% confidence interval [CI] 0.95-3.68; P = 0.07; n = 437; moderate quality of evidence) or hypovolemia (RR: 0.98, 95% CI: 0.32-2.97; P = 0.97; n = 437; moderate quality of evidence) between the aggressive and CFR groups. A significantly higher risk of fluid overload (RR: 3.25, 95% CI: 1.53-6.93; P <0.01; n = 249; low quality of evidence) was observed in the aggressive fluid resuscitation (AFR) group than the controlled group. Additionally, the risk of intensive care unit admission ( P = 0.02) and the length of hospital stay ( P <0.01) as partial secondary outcomes were higher in the AFR group. TSA suggested that more studies were required to draw precise conclusions.

CONCLUSION

For AP patients without organ failure on admission, CFR may be superior to AFR with respect to both efficacy and safety outcomes.

REGISTRATION

PROSPERO; https://www.crd.york.ac.uk/PROSPERO/ ; CRD 42022363945.

RNA-sequencing approach for exploring the protective mechanisms of dexmedetomidine on pancreatic injury in severe acute pancreatitis

Background: Severe acute pancreatitis (SAP) is a severe form of acute pancreatitis with the potential to cause life-threatening complications. Patients with acute SAP require surgical intervention and are admitted to the intensive care unit for non-invasive ventilation. Dexmedetomidine (Dex) is currently used by intensive care clinicians and anaesthesiologists as an adjunctive sedative. Therefore, the clinical availability of Dex makes it easier to implement in SAP treatment than developing new drugs. Methods: Randomly dividing thirty rats into sham-operated (Sham), SAP, and Dex groups. The severity of pancreatic tissue injury in each rat was assessed by Hematoxylin and eosin (HE) staining. Serum amylase activity and inflammatory factor levels were measured using commercially available kits. The expressions of necroptosis-related proteins, myeloperoxidase (MPO), CD68, and 4-hydroxy-trans-2-nonenal (HNE) were detected using immunohistochemistry (IHC). Transferase-mediated dUTP nick-end labeling (TUNEL) staining was utilized to identify pancreatic acinar cell apoptosis. The subcellular organelle structure of pancreatic acinar cells was observed using transmission electron microscopy. The regulatory effect of Dex on the gene expression profile of SAP rat pancreas tissue was investigated using RNA sequencing. We screened for differentially expressed genes (DEGs). Quantitative real-time PCR (qRT-PCR) measured critical DEG mRNA expression in rat pancreatic tissues. Results: Dex attenuated SAP-induced pancreatic injury, infiltration of neutrophils and macrophages, and oxidative stress. Dex inhibited the expression of necroptosis-associated proteins RIPK1, RIPK3, and MLKL and alleviated apoptosis in acinar cells. Dex also mitigated the structural damage caused by SAP to mitochondria and endoplasmic reticulum. Dex inhibited SAP-induced 473 DEGs, as determined by RNA sequencing. Dex may regulate SAP-induced inflammatory response and tissue damage by inhibiting the toll-like receptor/nuclear factor κB (TLR/NF-κB) signaling pathway and neutrophil extracellular trap formation. Conclusion: This study elucidated the remarkable effect of Dex against SAP and investigated the potential mechanism of action, providing an experimental base for the future clinical application of Dex in the treatment of SAP.

Effectiveness of Chengqi-series decoctions in treating severe acute pancreatitis: A Systematic review and meta-analysis

BACKGROUND

Evidence suggests that Dachengqi and its modified decoctions are effective for treating abdominal pain, multiple organ dysfunction syndrome (MODS) and inflammation in various disease conditions. We performed a meta-analysis to ascertain the effectiveness of a series of chengqi decoctions in patients with severe acute pancreatitis (SAP).

METHODS

We searched Pubmed, Embase, Cochrane library, Web of Science, Chinese National Knowledge Infrastructure, Chinese Biomedical Literature, Wanfang database and China Science and Technology Journal Database before August 2022 to identify eligible randomized controlled trials (RCTs). Mortality and MODS were chosen as primary outcomes. Secondary outcomes included time until relief of abdominal pain, APACHE II score, complications, effectiveness, IL-6 and TNF-α levels. The risk ratio (RR) and standardized mean difference (SMD) with a 95% confidence interval (CI) were selected as effect measures. The quality of evidence was independently assessed by two reviewers using Grading of Recommendations Assessment Development and Evaluation (GRADE) system.

RESULTS

Twenty-three RCTs (n = 1865) were finally included. The results showed that, compared with routine therapies, chengqi-series decoctions (CQSDs) treatment groups were associated with lower mortality rate (RR: 0.41, 95%CI: 0.32 to 0.53, p = 0.992) and incidence of MODS (RR: 0.48, 95%CI: 0.36 to 0.63, p = 0.885). They also reduced remission time of abdominal pain (SMD: -1.66, 95%CI: -1.98 to -1.35, p = 0.000), complications (RR: 0.52, 95%CI: 0.39 to 0.68, p = 0.716), APACHE II score (SMD: -1.04, 95%CI:-1.55 to -0.54, p = 0.003), IL-6 (SMD: -1.5, 95%CI: -2.16 to -0.85, p = 0.000), TNF-α (SMD: -1.18, 95%CI: -1.71 to -0.65, p = 0.000), and improved curative effectiveness (RR:1.22, 95%CI: 1.14 to 1.31, p = 0.757). The certainty of the evidence for these outcomes was low to moderate.

CONCLUSION

CQSDs seem to be effective therapy for SAP patients with notable reductions in mortality, MODS and abdominal pain, with low quality evidence. Large-scale, multi-center RCTs that are more meticulous are advised in order to produce superior evidence.

Extracellular Vesicle ITGAM and ITGB2 Mediate Severe Acute Pancreatitis-Related Acute Lung Injury

Integrins expressed on extracellular vesicles (EVs) secreted by various cancers are reported to mediate the organotropism of these EVs. Our previous experiment found that pancreatic tissue of mice with severe cases of acute pancreatitis (SAP) overexpresses several integrins and that serum EVs of these mice (SAP-EVs) can mediate acute lung injury (ALI). It is unclear if SAP-EV express integrins that can promote their accumulation in the lung to promote ALI. Here, we report that SAP-EV overexpress several integrins and that preincubation of SAP-EV with the integrin antagonist peptide HYD-1 markedly attenuates their pulmonary inflammation and disrupt the pulmonary microvascular endothelial cell (PMVEC) barrier. Further, we report that injecting SAP mice with EVs engineered to overexpress two of these integrins (ITGAM and ITGB2) can attenuate the pulmonary accumulation of pancreas-derived EVs and similarly decrease pulmonary inflammation and disruption of the endothelial cell barrier. Based on these findings, we propose that pancreatic EVs can mediate ALI in SAP patients and that this injury response could be attenuated by administering EVs that overexpress ITGAM and/or ITGB2, which is worthy of further study due to the lack of effective therapies for SAP-induced ALI.

Therapeutic effects and mechanism of Atractylodis rhizoma in acute lung injury: Investigation based on an Integrated approach

Acute lung injury (ALI) is characterized by an excessive inflammatory response. Atractylodes lancea (Thunb.) DC. is a traditional chinese medicine with good anti-inflammatory activity that is commonly used clinically for the treatment of lung diseases in China; however, its mechanism of against ALI is unclear. We clarified the therapeutic effects of ethanol extract of Atractylodis rhizoma (EEAR) on lipopolysaccharide (LPS)-induced ALI by evaluation of hematoxylin-eosin (HE) stained sections, the lung wet/dry (W/D) ratio, and levels of inflammatory factors as indicators. We then characterized the chemical composition of EEAR by ultra-performance liquid chromatography and mass spectrometry (UPLC-MS) and screened the components and targets by network pharmacology to clarify the signaling pathways involved in the therapeutic effects of EEAR on ALI, and the results were validated by molecular docking simulation and Western blot (WB) analysis. Finally, we examined the metabolites in rat lung tissues by gas chromatography and mass spectrometry (GC-MS). The results showed that EEAR significantly reduced the W/D ratio, and tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6) levels in the lungs of ALI model rats. Nineteen components of EEAR were identified and shown to act synergetically by regulating shared pathways such as the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)-protein kinase B (AKT) signaling pathways. Ferulic acid, 4-methylumbelliferone, acetylatractylodinol, atractylenolide I, and atractylenolide III were predicted to bind well to PI3K, AKT and MAPK1, respectively, with binding energies < -5 kcal/mol, although only atractylenolide II bound with high affinity to MAPK1. EEAR significantly inhibited the phosphorylation of PI3K, AKT, p38, and ERK1/2, thus reducing protein expression. EEAR significantly modulated the expression of metabolites such as D-Galactose, D-Glucose, serine and D-Mannose. These metabolites were mainly concentrated in the galactose and amino acid metabolism pathways. In conclusion, EEAR alleviates ALI by inhibiting activation of the PI3K-AKT and MAPK signaling pathways and regulating galactose metabolism, providing a new direction for the development of drugs to treat ALI.

Polystyrene microplastics aggravate acute pancreatitis in mice

Microplastics (MPs) with a diameter of < 5mm are emerging as a new type of environmental pollutants. With the discovery of MPs in human tissues, the health risks of MPs have attracted considerable attention in recent years. In this study, we aimed to investigate the impact of MPs on acute pancreatitis (AP). We exposed male mice to 100 and 1000μg/L polystyrene MPs for 28 days, then intraperitoneally injected mice with cerulein to develop acute pancreatitis (AP). The results demonstrated that MPs dose-dependently exacerbated pancreatic injuries and inflammation in AP. High-dose MPs significantly increased intestinal barrier disruption in AP mice, which may be partly responsible for the aggravation of AP. Moreover, through tandem mass tag (TMT)- based proteomics of pancreatic tissues, we screened 101 differentially expressed proteins (DEPs) between AP mice and high-dose MPs-treated AP mice. Gene Ontology and KEGG Pathway analysis revealed that the DEPs were mainly implicated in the molecular events including cytoskeleton organization, acute inflammatory response, arginine metabolism, etc. These mechanisms may also contribute to the aggravating AP effects of MPs. Collectively, our data provide new evidence for the harmful potential of MPs.

CEBPB promotes gastrointestinal motility dysfunction after severe acute pancreatitis via the MALAT1/CIRBP/ERK axis

Severe acute pancreatitis (SAP) is a kind of reversible inflammatory process of the exocrine pancreas with gastrointestinal motility dysfunction involved. Studies have highlighted the role of long noncoding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT1) in AP. However, the mechanism underlying its role in the gastrointestinal motility dysfunction remains undefined. Hence, we explored the regulatory role of MALAT1 in gastrointestinal motility dysfunction following SAP. Then, the expression of CCAAT/enhancer-binding protein beta (CEBPB), MALAT1 and cold-inducible RNA binding protein (CIRBP) was detected in plasma of SAP patients and pancreatic and intestinal tissues of SAP mouse models with their correlation analyzed also. Additionally, the effect of MALAT1 on the pancreatic and intestinal injury, expression of inflammatory factors and the ERK pathway-related genes as well as gastrointestinal motility dysfunction was assessed using ectopic expression and depletion experiments. CEBPB, MALAT1 and CIRBP were highly expressed in plasma of SAP patients and pancreatic and intestinal tissues of SAP mice. Further analysis showed that knockdown of MALAT1 could alleviate pancreatic and intestinal injury, reduce inflammation, and prevent gastrointestinal motility dysfunction in SAP mice. The transcription factor CEBPB could bind to the promoter region of MALAT1, thus activating the transcription of MALAT1. MALAT1 interacted with CIRBP and inhibited the degradation of CIRBP, leading to activated extracellular signal-regulated kinase (ERK) pathway and the resultant gastrointestinal motility dysfunction. In conclusion, CEBPB exhibits a promoting activity towards gastrointestinal motility dysfunction in SAP by pumping up MALAT1 expression and activating the CIRBP-dependent ERK pathway.

No evidence for the benefit of PPIs in the treatment of acute pancreatitis: a systematic review and meta-analysis

Although current guidelines do not recommend the use of proton pump inhibitors (PPIs) in the standard of care of acute pancreatitis (AP), they are often prescribed in clinical practice, mainly for ulcer stress prophylaxis. In this systematic review and meta-analysis we evaluated the association between the use of PPIs in the management of AP and various clinical outcomes. We conducted the systematic research in six databases without restrictions on January 24th, 2022. We investigated adult patient with AP, who were treated with PPI compared to conventional therapy. The pooled odds ratios, mean differences, and corresponding 95% confidence intervals were calculated with random effect model. We included six RCTs and three cohort studies, consisting of 28,834 patients. We found a significant decrease in the rate of pancreatic pseudocyst formation in patients who received PPI treatment. PPI use was associated with a higher risk of GI bleeding, however this finding could be due to the patients' comorbid conditions. We found no significant difference in the rates of 7-day mortality, length of hospital stay, and acute respiratory distress syndrome between the groups. The available data on this topic are limited; therefore, further well designed RCTs are needed to evaluate the potential benefits and adverse effects of PPIs in AP.

Ferroptosis in Rat Lung Tissue during Severe Acute Pancreatitis-Associated Acute Lung Injury: Protection of Qingyi Decoction

Qingyi decoction (QYD) has anti-inflammatory pharmacological properties and substantial therapeutic benefits on severe acute pancreatitis (SAP) in clinical practice. However, its protective mechanism against SAP-associated acute lung injury (ALI) remains unclear. In this study, we screened the active ingredients of QYD from the perspective of network pharmacology to identify its core targets and signaling pathways against SAP-associated ALI. Rescue experiments were used to determine the relationship between QYD and ferroptosis. Then, metabolomics and 16s rDNA sequencing were used to identify differential metabolites and microbes in lung tissue. Correlation analysis was utilized to explore the relationship between core targets, signaling pathways, metabolic phenotypes, and microbial flora, sorting out the potential molecular network of QYD against SAP-associated lung ALI. Inflammatory damage was caused by SAP in the rat lung. QYD could effectively alleviate lung injury, improve respiratory function, and significantly reduce serum inflammatory factor levels in SAP rats. Network pharmacology and molecular docking identified three key targets: ALDH2, AnxA1, and ICAM-1. Mechanistically, QYD may inhibit ferroptosis by promoting the ALDH2 expression and suppress neutrophil infiltration by blocking the cleavage of intact AnxA1 and downregulating ICAM-1 expression. Ferroptosis activator counteracts the pulmonary protective effect of QYD in SAP rats. In addition, seven significant differential metabolites were identified in lung tissues. QYD relatively improved the lung microbiome's abundance in SAP rats. Further correlation analysis determined the correlation between ferroptosis, differential metabolites, and differential microbes. In this work, the network pharmacology, metabolomics, and 16s rDNA sequencing were integrated to uncover the mechanism of QYD against SAP-associated ALI. This novel integrated method may play an important role in future research on traditional Chinese medicine.

Xanthohumol alleviates oxidative stress and impaired autophagy in experimental severe acute pancreatitis through inhibition of AKT/mTOR

Severe acute pancreatitis (SAP) is a lethal gastrointestinal disorder, yet no specific and effective treatment is available. Its pathogenesis involves inflammatory cascade, oxidative stress, and autophagy dysfunction. Xanthohumol (Xn) displays various medicinal properties, including anti-inflammation, antioxidative, and enhancing autophagic flux. However, it is unclear whether Xn inhibits SAP. This study investigated the efficacy of Xn on sodium taurocholate (NaT)-induced SAP (NaT-SAP) in vitro and in vivo. First, Xn attenuated biochemical and histopathological responses in NaT-SAP mice. And Xn reduced NaT-induced necrosis, inflammation, oxidative stress, and autophagy impairment. The mTOR activator MHY1485 and the AKT activator SC79 partly reversed the treatment effect of Xn. Overall, this is an innovative study to identify that Xn improved pancreatic injury by enhancing autophagic flux via inhibition of AKT/mTOR. Xn is expected to become a novel SAP therapeutic agent.

Naringenin protects against acute pancreatitis-associated intestinal injury by inhibiting NLRP3 inflammasome activation via AhR signaling

Background: In this study, we examined the functions and mechanisms by which naringenin protects against SAP (severe acute pancreatitis)-related intestinal injury by modulating the AhR/NLRP3 signaling pathway. Material and methods: Fifteen healthy male C57BL/6 mice were randomly divided into SAP (n = 12) and normal (n = 3) groups. Mice in the SAP group received caerulein and lipopolysaccharide intraperitoneal injections and were then randomly assigned to the SAP, NAR, CH223191, and Dexamethasone (DEX) groups. Pathological changes in the pancreatic and intestinal mucosa were observed by Hematoxylin & Eosin (H&E) staining. In vitro, RAW264.7 cells were exposed to lipopolysaccharide and treated with naringenin. The levels of NLRP3, AhR, IL-1β, TNF, and IL-6 in the SAP model and RAW264.7 cells were evaluated by enzyme-linked immunosorbent assay (ELISA), quantitative real-time PCR (qRT-PCR), western blot, and immunohistochemistry. The nuclear translocation of AhR was shown by immunofluorescence. AutoDockTools was used to predict the conformations of naringenin-AhR binding, and PyMol 2.4 was used to visualize the conformations. Results: Mouse pancreatic and intestinal injury was alleviated by treatment with naringenin. Naringenin inhibited the activation of the NLRP3 inflammasome and inhibited damage to intestinal tight junctions. Moreover, naringenin increased AhR nuclear translocation and activated the AhR pathway. Conclusion: Naringenin can reduce SAP-associated intestinal injury by inhibiting the activation of the NLRP3 inflammasome via the AhR signaling pathway.

Weaning stress and intestinal health of piglets: A review

Weaning is considered to be one of the most critical periods in pig production, which is related to the economic benefits of pig farms. However, in actual production, many piglets are often subjected to weaning stress due to the sudden separation from the sow, the changes in diet and living environment, and other social challenges. Weaning stress often causes changes in the morphology and function of the small intestine of piglets, disrupts digestion and absorption capacity, destroys intestinal barrier function, and ultimately leads to reduced feed intake, increased diarrhea rate, and growth retardation. Therefore, correctly understanding the effects of weaning stress on intestinal health have important guiding significance for nutritional regulation of intestinal injury caused by weaning stress. In this review, we mainly reviewed the effects of weaning stress on the intestinal health of piglets, from the aspects of intestinal development, and intestinal barrier function, thereby providing a theoretical basis for nutritional strategies to alleviate weaning stress in mammals in future studies.

Stellate ganglion block relieves acute lung injury induced by severe acute pancreatitis via the miR-155-5p/SOCS5/JAK2/STAT3 axis

Acute lung injury (ALI), a prevalent complication of severe acute pancreatitis (SAP), is also a leading contributor to respiratory failure and even death of SAP patients. Here, we intended to investigate the function and mechanism of stellate ganglion block (SGB) in ameliorating SAP-induced ALI (SAP-ALI). We engineered an SAP-ALI model in rats and treated them with SGB. HE staining and the dry and wet method were implemented to evaluate pathological alterations in the tissues and pulmonary edema. The rats serum changes of the profiles of TNF-α, IL-6, IL-1β, and IL-10 were examined. The profiles of miR-155-5p and SOCS5/JAK2/STAT3 were detected. Functional assays were performed for confirming the role of miR-155-5p in modulating the SOCS5/JAK2/STAT3 pathway in pulmonary epithelial cells. Our findings revealed that SGB vigorously alleviated SAP rat lung tissue damage and lung edema and lessened the generation of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β. SGB enhanced SOCS5 expression, hampered miR-155-5p, and suppressed JAK2/STAT3 pathway activation. As evidenced by mechanism studies, miR-155-5p targeted the 3′UTR of SOCS5 and repressed its expression, hence resulting in JAK2/STAT3 pathway activation. During animal trials, we discovered that SGB ameliorated SAP-ALI, boosted SOCS5 expression, and mitigated the levels of pro-inflammatory factors and miR-155-5p in the plasma. In vitro, miR-155-5p overexpression substantially facilitated pulmonary epithelial cell apoptosis, inflammation, and JAK2/STAT3 pathway activation and restrained SOCS5 expression. All in all, our work hinted that SGB could modulate the miR-155-5p/SOCS5/JAK2/STAT3 axis to alleviate SAP-ALI.

Inhibition of Necroptosis in Acute Pancreatitis: Screening for RIPK1 Inhibitors

This work utilizes the anthraquinone (AQ) database to identify potential inhibitors of the RIPK1 protein for developing medicines targeting AP-associated necroptosis. Screening for necroptosis-related genes that play a crucial role in AP is based on the GEO and GSEA databases. An optimum AQ for receptor-interacting protein kinase 1 (RIPK1) inhibition was virtually screened using the Discovery Studio 2019 tool, with a previously described RIPK1 inhibitor (necrostatin-1) as a reference ligand. Using LibDock and CDOCKER molecular docking, an AQ that robustly binds to RIPK1 was identified. The DOCKTHOR web server was used to calculate the ligand–receptor binding energy. The pharmacological properties and toxicity of potential AQ were evaluated using the ADME module and ProTox-II web server. The stability of ligand–receptor complexes was examined using molecular dynamics (MD) simulation. All 12 AQs showed solid binding activity to RIPK1, 5 of which were superior to necrostatin-1. Rheochrysin and Aloe-Emodin-8-O-Beta-D-Glucopyranoside (A8G) were safe RIPK1 inhibitors based on pharmacological characterization and toxicity studies. Additionally, the potential energy of the candidate AQs with RIPK1 was greater than that of the reference ligand, necrostatin-1. MD simulations also showed that the candidate AQs could bind stably to RIPK1 in the natural environment. Rheochrysin and A8G are safe and effective anthraquinones that inhibit the RIPK1 protein. This research takes a first step toward developing RIPK1 inhibitors by screening AQs that have the potential to be more effective than the reference ligand necrostatin-1.

Extracellular vesicles in the pathogenesis and treatment of acute lung injury

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are common life-threatening lung diseases associated with acute and severe inflammation. Both have high mortality rates, and despite decades of research on clinical ALI/ARDS, there are no effective therapeutic strategies. Disruption of alveolar-capillary barrier integrity or activation of inflammatory responses leads to lung inflammation and injury. Recently, studies on the role of extracellular vesicles (EVs) in regulating normal and pathophysiologic cell activities, including inflammation and injury responses, have attracted attention. Injured and dysfunctional cells often secrete EVs into serum or bronchoalveolar lavage fluid with altered cargoes, which can be used to diagnose and predict the development of ALI/ARDS. EVs secreted by mesenchymal stem cells can also attenuate inflammatory reactions associated with cell dysfunction and injury to preserve or restore cell function, and thereby promote cell proliferation and tissue regeneration. This review focuses on the roles of EVs in the pathogenesis of pulmonary inflammation, particularly ALI/ARDS.

Fighting Fire with Fire: Exosomes and Acute Pancreatitis-Associated Acute Lung Injury

Acute pancreatitis (AP) is a prevalent clinical condition of the digestive system, with a growing frequency each year. Approximately 20% of patients suffer from severe acute pancreatitis (SAP) with local consequences and multi-organ failure, putting a significant strain on patients' health insurance. According to reports, the lungs are particularly susceptible to SAP. Acute respiratory distress syndrome, a severe type of acute lung injury (ALI), is the primary cause of mortality among AP patients. Controlling the mortality associated with SAP requires an understanding of the etiology of AP-associated ALI, the discovery of biomarkers for the early detection of ALI, and the identification of potentially effective drug treatments. Exosomes are a class of extracellular vesicles with a diameter of 30-150 nm that are actively released into tissue fluids to mediate biological functions. Exosomes are laden with bioactive cargo, such as lipids, proteins, DNA, and RNA. During the initial stages of AP, acinar cell-derived exosomes suppress forkhead box protein O1 expression, resulting in M1 macrophage polarization. Similarly, macrophage-derived exosomes activate inflammatory pathways within endothelium or epithelial cells, promoting an inflammatory cascade response. On the other hand, a part of exosome cargo performs tissue repair and anti-inflammatory actions and inhibits the cytokine storm during AP. Other reviews have detailed the function of exosomes in the development of AP, chronic pancreatitis, and autoimmune pancreatitis. The discoveries involving exosomes at the intersection of AP and acute lung injury (ALI) are reviewed here. Furthermore, we discuss the therapeutic potential of exosomes in AP and associated ALI. With the continuous improvement of technological tools, the research on exosomes has gradually shifted from basic to clinical applications. Several exosome-specific non-coding RNAs and proteins can be used as novel molecular markers to assist in the diagnosis and prognosis of AP and associated ALI.

Toll-Like Receptor 9 Signaling Pathway Contributes to Intestinal Mucosal Barrier Injury in Mice With Severe Acute Pancreatitis

OBJECTIVES

The purpose of this study was to investigate the role and mechanism of toll-like receptor 9 (TLR9) in intestinal mucosal barrier injury in mice with severe acute pancreatitis (SAP).

METHODS

The mice were randomly divided into 3 groups: control group, SAP group, and TLR9 antagonist-treated group. The expression of tumor necrosis factor-α, interleukin-1β, interleukin-6, diamine oxidase, and endotoxin core antibodies were detected by enzyme-linked immunosorbent assay. The protein expression of zonula occluden-1 (ZO)-1, occludin, TLR9, myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor-associated factor 6 (TRAF6), p-nuclear factor (NF)-κB p65, and NF-κB p65 were detected by Western blot. TdT-mediated dUTP nick-end labeling staining was used for detecting intestinal epithelial cell apoptosis.

RESULTS

The expression of TLR9 and its related pathway proteins MyD88, TRAF6, and p-NF-κB p65 in the intestinal tract of SAP mice were significantly increased compared with that of control mice. Inhibition of the TLR9 expression could reduce the level of serum proinflammatory cytokines, reduce the apoptosis of intestinal epithelial cells, improve intestinal permeability, and ultimately reduce the damage of intestinal mucosal barrier function in SAP.

CONCLUSIONS

Toll-like receptor 9/MyD88/TRAF6/NF-κB signaling pathway plays an important role in intestinal mucosal barrier injury of SAP.

C/EBPβ Promotes LPS-Induced IL-1β Transcription and Secretion in Alveolar Macrophages via NOD2 Signaling

Objective

C/EBPβ, a crucial transcription factor, regulates innate immunity and inflammatory responses. However, the role played by C/EBPβ in alveolar macrophage (AM) inflammatory responses remains unknown. This study aimed to investigate the role and mechanism of C/EBPβ in alveolar macrophages (AMs) from the transcriptional level and to search for natural compounds targeting C/EBPβ.

Methods

Rat AMs were infected with Lv-sh-C/EBPβ and treated with LPS, and the expression levels of iNOS, TNF-α, IL-6, and IL-1β were measured by RT-qPCR, Western blotting, and ELISA. Mechanistically, transcriptome sequencing (RNA-seq) revealed changes in gene expression patterns in AMs after LPS stimulation and C/EBPβ knockdown. Functional enrichment analyses and rescue experiments identified and validated inflammation-associated cell signaling pathways regulated by C/EBPβ. Furthermore, virtual screening was used to search for natural compounds that inhibit C/EBPβ with the structure of helenalin as a reference.

Results

Following stimulation with LPS, AMs exhibited an increased expression of C/EBPβ. C/EBPβ knockdown significantly decreased the expression levels of inflammatory mediators. A total of 374 differentially expressed genes (DEGs) were identified between LPS-stimulated C/EBPβ knockdown and negative control cells. The NOD-like receptor signaling may be a key target for C/EBPβ, according to functional enrichment analyses of the DEGs. Further experiments showed that the muramyl dipeptide (MDP, NOD2 agonist) reversed the downregulation of inflammatory mediators and the NF-κB pathway caused by the C/EBPβ knockdown. The virtual screening revealed that N-caffeoyltryptophan, orilotimod, and petasiphenone have comparable pharmacological properties to helenalin (a known C/EBPβ inhibitor) and demonstrate a great binding capacity to C/EBPβ.

Conclusion

Ablation of C/EBPβ may attenuate LPS-induced inflammatory damage in AMs by inhibiting the NOD2 receptor signaling pathway. Three natural compounds, N-caffeoyltryptophan, orilotimod, and petasiphenone, may be potential C/EBPβ inhibitors.

USP25 Deficiency Exacerbates Acute Pancreatitis via Up-Regulating TBK1-NF-κB Signaling in Macrophages

BACKGROUND & AIMS

Severe acute pancreatitis can easily lead to systemic inflammatory response syndrome and death. Macrophages are known to be involved in the pathophysiology of acute pancreatitis (AP), and macrophage activation correlates with disease severity. In this study, we examined the role of ubiquitin-specific protease 25, a deubiquitinating enzyme and known regulator of macrophages, in the pathogenesis of AP.

METHODS

We used L-arginine, cerulein, and choline-deficient ethionine-supplemented diet-induced models of AP in Usp25^-/- mice and wild-type mice. We also generated bone marrow Usp25^-/- chimeric mice and initiated L-arginine-mediated AP. Primary acinar cells and bone marrow-derived macrophages were isolated from wild-type and Usp25^-/- mice to dissect molecular mechanisms.

RESULTS

Our results show that Usp25 deficiency exacerbates pancreatic and lung injury, neutrophil and macrophage infiltration, and systemic inflammatory responses in L-arginine, cerulein, and choline-deficient ethionine-supplemented diet-induced models of AP. Bone marrow Usp25^-/- chimeric mice challenged with L-arginine show that Usp25 deficiency in macrophages exaggerates AP by up-regulating the TANK-binding kinase 1 (TBK1)-nuclear factor-κB (NF-κB) signaling pathway. Similarly, in vitro data confirm that Usp25 deficiency enhances the TBK1-NF-κB pathway, leading to increased expression of inflammatory cytokines in bone marrow-derived macrophages.

CONCLUSIONS

Usp25 deficiency in macrophages enhances TBK1-NF-κB signaling, and the induction of inflammatory chemokines and type I interferon-related genes exacerbates pancreatic and lung injury in AP.

Echinacoside alleviates pancreatic injury via exerting anti-inflammatory and anti-oxidant activities in a rat model of acute pancreatitis

BACKGROUND

Echinacoside (ECH) has anti-inflammatory and antioxidant effects, and can improve multiple organ injuries. However, the effect and potential mechanism of action of ECH on severe acute pancreatitis (SAP) are still unclear.

AIM

To investigate the protective effect of ECH on the pancreas of SAP model rats and the potential mechanism involved.

METHODS

Rats were randomly divided into sham group (Sham), ECH control group (Sham + ECH), SAP model group (SAP), and ECH treatment group (SAP + ECH), with 10 rats each. Ascites volume and the activities of amylase and lipase in serum were determined. HE staining was used to analyze the histological changes in each group, and TUNEL assay was used to observe the apoptosis of pancreatic acinar cells. The levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and malondialdehyde (MDA) and the activities of glutathione peroxidase (GSH-PX), superoxide dismutase (SOD), and myeloperoxidase (MPO) in pancreatic tissues were measured by tissue biochemistry. The expression levels of B cell lymphoma-2 (Bcl-2), Bcl2-associated X protein (Bax), cleaved caspase-3, nuclear factor E2-related factor 2 (NRF-2), Toll-like receptor 4 (TLR-4), and nuclear factor κB (NF-κB) p65 proteins in pancreatic tissue were detected by Western blot.

RESULTS

Compared with the SAP group, ascites volume and serum amylase and lipase activities in the SAP + ECH group were decreased (P < 0.05); pancreatic tissue edema, inflammatory cell infiltration, and necrosis scores and total histological score were decreased (P < 0.05); the number of TUNEL positive cells was reduced; the levels of TNF-α, IL-6, MDA, and MPO activity in pancreatic tissue homogenate were decreased (P < 0.05), and the activities of SOD and GSH-Px were increased (P < 0.05); the expression levels of Bax, cleaved caspase-3, TLR-4, and NF-κB p65 were decreased (P < 0.05), and the expression levels of Bcl-2 and NRF-2 were increased (P < 0.05).

CONCLUSION

ECH has anti-inflammatory, anti-oxidant, and anti-injury effects in pancreatic tissues of SAP model rats, which may be related to the downregulation of TLR-4, NF-κB p65, and Bax expression and the upregulation of NRF-2 and Bcl-2 expression.

How do intestinal probiotics restore the intestinal barrier?

The intestinal barrier is a structure that prevents harmful substances, such as bacteria and endotoxins, from penetrating the intestinal wall and entering human tissues, organs, and microcirculation. It can separate colonizing microbes from systemic tissues and prevent the invasion of pathogenic bacteria. Pathological conditions such as shock, trauma, stress, and inflammation damage the intestinal barrier to varying degrees, aggravating the primary disease. Intestinal probiotics are a type of active microorganisms beneficial to the health of the host and an essential element of human health. Reportedly, intestinal probiotics can affect the renewal of intestinal epithelial cells, and also make cell connections closer, increase the production of tight junction proteins and mucins, promote the development of the immune system, regulate the release of intestinal antimicrobial peptides, compete with pathogenic bacteria for nutrients and living space, and interact with the host and intestinal commensal flora to restore the intestinal barrier. In this review, we provide a comprehensive overview of how intestinal probiotics restore the intestinal barrier to provide new ideas for treating intestinal injury-related diseases.

Calycosin Improves Intestinal Mucosal Barrier Function after Gastrectomy in Rats through Alleviating Bacterial Translocation, Inflammation, and Oxidative Stress

Objective

Calycosin is the main bioactive extract of Astragali Radix with anti-inflammation, antioxidant, and anticancer properties. Here, our study evaluated the protective effects and mechanisms of calycosin on intestinal mucosal barrier under gastrectomy.

Methods

After receiving gastrectomy, the rats were administrated with 20 mg/kg, 40 mg/kg, or 80 mg/kg calycosin. Endotoxin, bacterial translocation, and intestinal bacterial flora were assayed. Intestinal injury was detected via hematoxylin and eosin staining. Tight junction indicators (occludin, claudin, and ZO-1) and apoptotic proteins (Bax, Bcl-2, and cleaved caspase 3) were examined in intestinal tissues. Inflammatory indicators (IL-1β, IL-6, and TNF-α) were examined in serum or intestinal specimens via ELISA. Apoptosis was assessed via TUNEL staining. IgA + B cells in intestinal tissues and sIgA in intestinal lumen were examined through immunohistochemistry and ELISA, respectively. Oxidative stress indicators (TSH, SOD, CAT, GSH-Px, and MDA) were also detected via ELISA.

Results

Our results showed that calycosin administration decreased endotoxin levels in peripheral blood, intestine, and portal vein blood; lowered the bacterial translocation ratio; and regained the balance among intestinal bacterial flora (comprising bifidobacterium, lactic acid bacillus, enterobacter, enterococcus, aerobic bacteria, and anaerobic bacteria) in the rats with gastrectomy. After calycosin treatment, intestinal mucosal damage of the rats with gastrectomy was ameliorated, with the increase in expression of tight junction proteins. Additionally, calycosin reduced intestinal inflammation, apoptosis, secretion of sIgA, and oxidative stress in the rats with gastrectomy.

Conclusion

Altogether, our findings demonstrate that calycosin may improve intestinal mucosal barrier function under gastrectomy via reducing bacterial translocation, inflammation, and oxidative stress.

The Mechanism of Lung and Intestinal Injury in Acute Pancreatitis: A Review

Acute pancreatitis (AP), as a common cause of clinical acute abdomen, often leads to multi-organ damage. In the process of severe AP, the lungs and intestines are the most easily affected organs aside the pancreas. These organ damages occur in succession. Notably, lung and intestinal injuries are closely linked. Damage to ML, which transports immune cells, intestinal fluid, chyle, and toxic components (including toxins, trypsin, and activated cytokines to the systemic circulation in AP) may be connected to AP. This process can lead to the pathological changes of hyperosmotic edema of the lung, an increase in alveolar fluid level, destruction of the intestinal mucosal structure, and impairment of intestinal mucosal permeability. The underlying mechanisms of the correlation between lung and intestinal injuries are inflammatory response, oxidative stress, and endocrine hormone secretion disorders. The main signaling pathways of lung and intestinal injuries are TNF-α, HMGB1-mediated inflammation amplification effect of NF-κB signal pathway, Nrf2/ARE oxidative stress response signaling pathway, and IL-6-mediated JAK2/STAT3 signaling pathway. These pathways exert anti-inflammatory response and anti-oxidative stress, inhibit cell proliferation, and promote apoptosis. The interaction is consistent with the traditional Chinese medicine theory of the lung being connected with the large intestine (fei yu da chang xiang biao li in Chinese). This review sought to explore intersecting mechanisms of lung and intestinal injuries in AP to develop new treatment strategies.

The gut-lung axis in severe acute Pancreatitis-associated lung injury: The protection by the gut microbiota through short-chain fatty acids

The role of gut microbiota in regulating the intestinal homeostasis, as well as the pathogenesis of severe acute pancreatitis-associated lung injury (PALI) is widely recognized. The bioactive functions of metabolites with small molecule weight and the detail molecular mechanisms of PALI mediated by "gut-lung axis" have gradually raised the attentions of researchers. Several studies have proved that short-chain fatty acids (SCFAs) produced by gut microbiome play crucial roles and varied activities in the process of PALI. However, relevant reviews reporting SCFAs in the involvement of PALI is lacking. In this review, we firstly introduced the synthetic and metabolic pathways of SCFAs, as well as the transport and signal transduction routes in brief. Afterwards, we focused on the possible mechanisms and clues of SCFAs to participate in the fight against PALI which referred to the inhibition of pathogen proliferation, anti-inflammatory effects, enhancement of intestinal barrier functions, and the maintenance and regulation of immune homeostasis via pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). In addition, the latest reported pathological and physiological mechanisms of the gut-lung axis involved in PALI were reviewed. Finally, we summarized the potential therapeutic interventions of PALI by targeting SCFAs, including dietary fiber supplementation, direct supplementation of SCFAs/prebiotics/probiotics, and drugs administration, which is expected to provide new sights for clinical use in the future.

Integrins are double-edged swords in pulmonary infectious diseases

Integrins are an important family of adhesion molecules that are widely distributed on immune cells in the lungs. Of note, accumulating evidences have shown that integrins are double-edged swords in pulmonary infectious diseases. On one hand, integrins promote the migration of immune cells to remove the invaded pathogens in the infected lungs. However, on the other hand, integrins also act as the targets for pathogens to escape from host immune system, which is a potential factor leading to further tissue damage. Thus, the innovative therapeutic strategies based on integrins has inspired well-founded hopes to treat pulmonary infectious diseases. In this review, we illustrate the involvement of integrins in pulmonary infectious diseases, and further discuss the innovative therapeutic targets based on integrins.

Heparin Protects Severe Acute Pancreatitis by Inhibiting HMGB-1 Active Secretion from Macrophages

Heparin has shown benefits in severe acute pancreatitis (SAP) therapy, but the underlying mechanisms were unknown. Extracellular high-mobility group protein-1 (HMGB-1) has been regarded as a central mediator contributing to inflammation exacerbation and disease aggravation. We hypothesized heparin attenuated the disease by targeting HMGB-1-related pathways. In the present study, the possible therapeutic roles of heparin and its non-anticoagulant derivatives, 6-O-desulfulted heparin and N-acylated-heparin, were determined on mouse models induced by “Two-Hit” of L-arginine. The compounds exhibited potent efficiency by substantially decreasing the pancreatic necrosis, macrophage infiltration, and serum inflammatory cytokine (IL-6 and TNF-α) concentration. Moreover, they greatly reduced the rapidly increasing extracellular HMGB-1 levels in the L-arginine injured pancreases. As a result, multiple organ failure and mortality of the mice were inhibited. Furthermore, the drugs were incubated with the RAW264.7 cells activated with damaged pancreatic tissue of SAP mice in vitro. They were found to inhibit HMGB-1 transfer from the nucleus to the plasma, a critical step during HMGB-1 active secretion from macrophages. The results were carefully re-examined with a caerulein and LPS induced mouse model, and similar results were found. The paper demonstrated heparin alleviated SAP independent of the anti-coagulant functions. Therefore, non-anticoagulant heparin derivatives might become promising approaches to treat patients suffering from SAP.

Intestinal Microbiota - An Unmissable Bridge to Severe Acute Pancreatitis-Associated Acute Lung Injury

Severe acute pancreatitis (SAP), one of the most serious abdominal emergencies in general surgery, is characterized by acute and rapid onset as well as high mortality, which often leads to multiple organ failure (MOF). Acute lung injury (ALI), the earliest accompanied organ dysfunction, is the most common cause of death in patients following the SAP onset. The exact pathogenesis of ALI during SAP, however, remains unclear. In recent years, advances in the microbiota-gut-lung axis have led to a better understanding of SAP-associated lung injury (PALI). In addition, the bidirectional communications between intestinal microbes and the lung are becoming more apparent. This paper aims to review the mechanisms of an imbalanced intestinal microbiota contributing to the development of PALI, which is mediated by the disruption of physical, chemical, and immune barriers in the intestine, promotes bacterial translocation, and results in the activation of abnormal immune responses in severe pancreatitis. The pathogen-associated molecular patterns (PAMPs) mediated immunol mechanisms in the occurrence of PALI via binding with pattern recognition receptors (PRRs) through the microbiota-gut-lung axis are focused in this study. Moreover, the potential therapeutic strategies for alleviating PALI by regulating the composition or the function of the intestinal microbiota are discussed in this review. The aim of this study is to provide new ideas and therapeutic tools for PALI patients.