Ji, Baoan

Background: Alterations in cardiovascular function are key features of severe acute pancreatitis (AP) and contribute substantially to mortality. Although sex differences in cardiovascular diseases are well recognized, with males generally exhibiting higher risk and poorer outcomes, their influence on AP-associated cardiovascular responses remains poorly defined. Therefore, we hypothesized that cerulein-induced AP causes severity-dependent and sex-specific changes in vascular integrity and cardiac function. Methods: Obesity has been associated with more severe forms of AP. Thus, mild and severe AP were induced by cerulein injections (100µg/kg/h×12) in lean (n=10 males, n=13 females) and obese (n=9 males, n=12 females) C57BL/6J mice, respectively. Vascular permeability was assessed by FITC-dextran extravasation. Cardiac function was assessed by echocardiography before and after cerulein injection. Cytokines were measured with multi-plex cytokine array and the role of angiopoietin-2 (Angpt2), an endothelial-derived regulator of vascular and cardiac responses, was evaluated using a neutralizing antibody. Results: Vascular permeability did not differ significantly between sexes in either AP model. In mild AP, males and females showed comparable increases in systolic function; however, in severe AP, only female mice maintained this adaptive systolic augmentation, assessed by fractional shortening (FS; 25.78±0.27% at baseline vs. 43.44±0.57% at endpoint, n=12, p<0.0001). This impaired cardiac adaptation in males was accompanied by increased myocardial inflammatory cytokines and elevated circulating free fatty acids. Among ten circulating cytokines measured, Angpt2 levels were significantly higher in males than females (male: 63.50±1.52ng/mL, n=9 vs. female: 41.37±2.68ng/mL, n=6, p=0.013) and were negatively correlated with systolic performance (FS; R 2 =0.75, p<0.0001), while positively associated with preload (end-diastolic volume; R 2 =0.55, p=0.0015). Unexpectedly, Angpt2 neutralization did not improve the cardiac adaptations in males and instead worsened cardiac performance as reflected by reduced FS (control IgG: 32.83±1.47%, n=4 vs. Anti-Angpt2: 22.88±0.64%, n=5, p=0.013) in severe AP. Conclusions: AP elicits both sex-dependent and sex-independent cardiovascular responses, with female mice exhibiting preserved cardiac adaptation, and Angpt2 is a potential compensatory mediator of cardiac protection in severe AP.

Ex vivo liver perfusion (EVLP) sustains human or large animal livers outside the body under near-physiological conditions, enabling functional monitoring for lactate clearance, bile production, and oxygen consumption and allowing targeted therapeutic interventions. Originally developed to optimize donor grafts for transplantation, EVLP has evolved into a powerful translational research platform bridging preclinical discovery and early clinical translation. This review discusses EVLP as a platform for gene therapy, immunotherapy, pharmacology, and personalized medicine, with particular emphasis on gene- and immune-based interventions as mechanistically mature exemplars. We consolidate advances in pharmacological testing and toxicity modeling, viral and non-viral gene delivery, genome engineering, and immunomodulation using perfused livers. We further describe emerging applications, including autologous EVLP pathways for organ-confined therapy, ex vivo liver surgery, and bioengineering strategies such as biliary organoid repair, RNA interference, and mitochondrial transfer. We highlight how these applications align with a paradigm shift in biomedical research, including the NIH’s recent initiative to prioritize human-based experimental models over animal-only studies. By leveraging transplant-declined or surgically resected organs that would otherwise be unused, ex vivo perfusion bridges the gap between pre-clinical testing and clinical practice, enabling real-time evaluation of interventions in functional human tissue. We discuss both the scientific opportunities afforded by EVLP and the technical, biosafety, and ethical challenges that must be addressed to enable responsible clinical translation.

Elucidating the structure and function of enteropeptidase (EP) is essential for advancing our understanding of its biological significance, particularly in regulating trypsinogen activation. Using cryo-EM and enzymatic activity, we uncovered the significance of the CUB2 domain in mediating the cleavage of macromolecular substrates. We identified crucial binding loops and key residues for EP’s proteolytic function. The mutation E574A enhanced the proteolytic activity of EP, whereas the mutation N619A diminished its cleavage efficiency, highlighting the importance of surface-charged interactions in modulating EP’s activity. A proteolytic cycle was proposed to deepen our understanding of the trypsinogen activation by EP. This work offers valuable insights into the molecular mechanisms underlying EP’s interaction with its substrate, and opens up avenues for therapeutically modulating EP-mediated proteolysis.

Abstract Background: Hemorrhagic necrotizing pancreatitis (HNP) is a highly lethal form of pancreatitis that lacks mechanism-based therapy. Intra-acinar enzyme activation is fundamental to pancreatitis initiation, yet it does not explain why only a subset of episodes progress to catastrophic hemorrhagic necrosis. Objective: To identify determinants of progression to lethal HNP and test a mechanism-based preventive intervention. Design: Using humanized trypsinogen mouse models and secretagogue regimens, we compared high-dose cerulein with low/moderate-dose cerulein and bombesin. We quantified pancreatic protease activity, performed blinded histopathologic scoring, assessed hemorrhage/vascular disruption, and evaluated enzyme localization and ductal injury by PRSS1 immunostaining. De-identified human pancreatic histology from HNP were examined. We tested a repurposed strategy using clinically approved agents for other indications: secretin to stimulate ductal fluid secretion and isosorbide mononitrate (ISMN) to promote ductal outflow via sphincter of Oddi relaxation. Results: High-dose cerulein induced robust intrapancreatic protease activation but predominantly caused edematous pancreatitis. Paradoxically, bombesin and low/moderate-dose cerulein elicited lower total pancreatic protease activity yet produced severe, frequently lethal HNP with vascular disruption and lobular ischemic necrosis. HNP was associated with intraductal enzyme accumulation and ductal injury. Secretin or ISMN alone showed limited protection, whereas combined secretin+ISMN prevented hemorrhagic necrotizing injury. Conclusion: Pancreatitis severity is determined not only by the magnitude of enzyme activation but also by where enzyme activity is exerted, implicating intraductal enzyme accumulation as a mechanistic determinant and therapeutic target in HNP. Coordinated enhancement of ductal secretion and outflow with clinically approved agents prevents HNP in vivo, supporting a translatable prevention strategy.

Abstract Primary liver cancers, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), arise from the neoplastic transformation of hepatocytes and cholangiocytes, respectively. Loss or downregulation of PTEN, a tumor suppressor negatively regulating the PI3K/AKT pathway, is frequently observed in CCA and HCC. Notably, PTEN mutations are observed at nearly twice the frequency in combined CCA-HCC tumors than either HCC or CCA alone. Using lineage-specific liver-targeted PTEN-deficient mouse models, we demonstrate that PTEN loss drives cellular dedifferentiation and tumorigenesis, a process that is critically dependent on AKT2. Mechanistically, PTEN deficiency induces activation of NOTCH and upregulation of transcriptional factor SOX9, which plays a central role in tumor cell transformation. In parallel, PTEN loss increases SMAD4 expression and sensitizes the tumor cells to TGFβ signaling, with TGFβ treatment repressing SOX9 expression in tumor cells lacking PTEN. Together, our study defined a critical role for PTEN-AKT2 signaling in maintaining liver epithelial lineage fidelity and revealed how its disruption promotes the conversion of mature hepatocytes or cholangiocytes into liver cancer stem-like cells (LCSCs). Furthermore, we identify a PTEN-dependent crosstalk between NOTCH and TGFβ pathways that governs liver tumor development. Together, this work provides mechanistic insight into lineage plasticity in liver cancer with implications for pathway-directed therapy.

Postoperative pancreatic fistula (POPF) is a critical complication following pancreatic surgeries, marked by leakage of pancreatic fluid due to anastomotic or pancreatic duct failure. Recent advancements have refined its definition, risk classification and management strategies. This review emphasises discussing new definitions, classification updates, predictive factors (both pancreatic and non-pancreatic), comparisons of surgical techniques and therapeutic advancements. Emerging trials and innovations, such as robotic-assisted surgery and personalised stents, are also addressed. The evolving understanding of POPF underscores the need for holistic and patient-centred surgical strategies.

Objective: Patients with chronic pancreatitis commonly experience abdominal pain, anxiety, depression, reduced mobility, and difficulty performing daily activities or maintaining employment. These factors contribute to diminished quality-of-life and high healthcare utilization. This study aims to explore the relationship between specific quality-of-life domains among patients with chronic pancreatitis. Methods: A 55-item online survey was administered to patients with the diagnosis of chronic pancreatitis at 3 Mayo Clinic sites from December 26, 2023, to December 26, 2024. The survey included validated questions assessing demographic, clinical, and quality-of-life metrics using EuroQol 5-Dimension 5-Level instrument—a standardized assessment tool that evaluates 5 key health dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression. Results: Of the 298 patients with chronic pancreatitis who completed the survey, employed patients had decreased odds of reporting problems with mobility (odds ratio [OR] = 0.45, P < .05), self-care (OR = 0.26, P < .01), usual activities (OR = 0.47, P < .05), and anxiety/depression (OR = 0.41, P < .05). Similarly, older patients had decreased odds of reporting problems with self-care (OR = 0.91, P < .01), usual activities (OR = 0.96, P < .01), pain/discomfort (OR = 0.96, P < .01) and anxiety/depression (OR = 0.92, P < .01). However, Medicare patients had greater odds of reporting problems with self-care (OR = 5.54, P < .01) and pain/discomfort (OR = 2.58, P < .05). Conclusions: Chronic pancreatitis impacts multiple dimensions of quality-of-life beyond pain. The EuroQol 5-Dimension 5-Level tool enables comprehensive assessment of physical and mental health. Our findings highlight key associations between patient characteristics and quality-of-life domains, supporting the need for individualized, deficit-targeted interventions. These results also suggest a potential role for vocational rehabilitation in promoting functional recovery and enhancing overall well-being in individuals with chronic pancreatitis.

ABSTRACTTissue‐specific gene manipulation using Cre/loxP or Flp/frt recombination systems is a cornerstone of genetically engineered mouse models. In this study, we aim to develop a novel hepatocyte‐specific, tamoxifen‐inducible Flp mouse line. BAC (bacterial artificial chromosome)‐Alb(albumin)‐FlpER2(estrogen receptor ligan binding domain) was developed by inserting IRES‐FlpER2 cDNA between the translation stop codon and 3′‐UTR of the mouse albumin gene in a bacterial artificial chromosome. Upon tamoxifen induction in mice crossed with reporter lines, western blotting, immunohistochemistry, immunofluorescence staining, and X‐gal staining (5‐bromo‐4‐chloro‐3‐indolyl‐β‐D‐galactopyranoside Staining) were used to verify the recombination efficiency and specificity of this mouse model. Recombination was highly efficient and specific in hepatocytes, with no recombination detected in intrahepatic cholangiocytes or other organs in this mouse model. We generated a new tamoxifen‐induced hepatocyte‐specific mouse model with highly efficient recombination specifically in hepatocytes, and this model can be used to generate tumor model lines.

AbstractA deeper understanding of pathophysiology, from the initiation of tumors of epithelial cells to the outcomes associated with it, is imperative to test potential interventions for these diseases. However, few models can accomplish this because of the complexity of origin cells and their transformation. We established an epithelial cell original tumor mouse model by conditional KrasG12D activation and tumor suppressor gene p53 deletion specifically in epithelial cells of the whole body using Cytokeratin 19 (CK19) promoter via Cre‐ERT mediation. Multiple tumors derived from epithelial cells developed in this novel model. This model can recapitulate the progress of intestinal, pancreatic, liver, lung, and subcutaneous tumors which derive from epithelial cells. This model is suitable for studying the pathophysiology of tumors derived from epithelial cells and may have the potential to test interventions.